AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
845 PM EDT WED JUL 14 1999
HAD A FEW STRONG T-STORMS IN THE AREA EARLIER THIS EVENING
ESPECIALLY IN A MERGER OF STORMS SOUTH OF MTH. ACTIVITY HAS ENDED
ACROSS THE CWA AT THIS TIME...WITH ONLY CONVECTION WELL NORTH OF THE
MARQUESAS...OVER THE FLORIDA PENINSULA AND OVER AND NEAR CUBA.
NO BOUNDARIES EVIDENT ON SATELLITE OR RADAR AND SLIGHTLY DRIER AIR
AHEAD OF TUTT LOW IN ATLANTIC IS STARING TO FILTER IN FROM THE EAST.
THIS IS EVIDENT IN EVENING SOUNDING WHICH SHOWS A DROP OF .20 INCHES
OF PRECIPITABLE WATER SINCE LAST EVENING (DOWN TO 1.8 INCHES). 21Z
RUC ALSO SHOWS DECREASING MEAN RELATIVE HUMIDITY TONIGHT WITH LESS
THAN 60% AFTER 06Z. SLIGHT ENHANCEMENT OCCURRING NEAR ANDROS
ISLAND...BUT I AM CONSIDERING LOWERING POPS TO WIDELY SCATTERED FOR
TONIGHT AND IF I DO I WOULD ALSO RAISE TEMPS WITH LESS RAIN-COOLED
AIR TAKING PLACE.
PLENTY OF DEBRIS CLOUDS FROM OFF CUBA AND THE CARIBBEAN SO WILL
MAINTAIN VARIABLE CLOUDINESS FOR TONIGHT.
DRIER AIR WILL CONTINUE TO WORK ITS WAY IN AHEAD OF TUTT LOW...SO NO
HIGHER THAN 20 OR 30% POPS THURSDAY AND THURSDAY NIGHT AS PER
CURRENT ZONE AND LFP FORECASTS.
WIND AT C-MAN SITES ONLY AROUND 10 KTS LATELY. EVENING EYW SOUNDING
HAS ONLY NEAR 10 KTS IN BOUNDARY LAYER AND 21Z RUC SHOWS WIND
INCREASING TO ONLY 10 TO 15 KTS OVERNIGHT. WILL LOWER WIND IN MARINE
PORTION OF LFP TO NO HIGHER THAN 10 TO 15 KTS AND SUGGEST MIA DO THE
SAME IN THEIR CWF.
.EYW...NONE.
MOHLIN
FXUS62 KTBW 150003 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
240 PM EDT WED JUL 14 1999
CURRENTLY...SATELLITE IR AND WATER VAPOR IMAGERY SHOW A BAND OF
DISTURBED WEATHER ASSOCIATED WITH REMNANTS OF STATIONARY FRONTAL
BOUNDARY OVER THE NORTHERN GULF OF MEXICO..NORTHERN FL...AND EASTERN
GA. 88DS SHOWING ONLY SCATTERED WEAK SHOWERS REMAINING OVER THE
FORECAST AREA AND COASTAL WATERS. MOST OF THE ACTIVITY THIS
MORNING HAS BEEN WEAKER AND LESS RAINFALL EFFICIENT THAN TUE.
MODELS ARE IN GOOD AGREEMENT AND CONTINUE TO SLOWLY WEAKEN THE UPPER
TROF OVER THE SOUTHEASTERN U.S. AS IT SHEARS NORTHEASTWARD. LATEST
RUC KEEPS VORTICITY AXIS FROM SRN MS TO SRN APPALACHIANS THROUGH THIS
EVENING..BUT WEAKENS THIS UPPER ENERGY BY LATE TONIGHT..WHILE AT THE
SAME TIME DECREASING THE RH SOMEWHAT OVER THE CWA. BOTTOM LINE..
CONDITIONS SHOULD IMPROVE A LITTLE..BUT STILL EXPECT POTENTIAL FOR
SOME SHOWERS AND THUNDERSTORMS ACROSS THE CWA. WITH BOUNDARY
WEAKENING OUT OF THE PICTURE..AND LOW LEVEL WINDS FORECAST TO REMAIN
SOUTHERLY..LOOK FOR BETTER CHANCE FOR SEA BREEZE CONVECTION ON THU.
TEMP GUIDANCE LOOKS MORE ON TRACK TODAY..FWC AND FAN CLOSE AND
MOSTLY ACCEPTED. I RECOMMEND ADJUSTING HIGHS DOWN A DEGREE OR TWO.
FAN POPS LOOK A LITTLE HIGH..RECOMMEND SLIGHT CHANCE THU FOR AL AND
GA..GOOD CHANCE FOR BIG BEND AND PANHANDLE.
TLH 71/90 71/91 2424
PFN 73/88 74/89 2424
DHN 70/90 71/91 2323
ABY 70/88 71/90 2322
VLD 70/89 71/90 2323 16
AFD
FXUS62 KMLB 141835 fl
STATE FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1030 PM EDT WED JUL 14 1999
UPPER-LEVEL PATTERN SHOWS RIDGE BUILDING WESTWARD FROM ATLANTIC.
CENTER AT 7/15 00Z NEAR CHS. SECOND UPPER RIDGE LOCATED OVER N TX.
WEAK TROUGH AXIS LOCATED BETWEEN RIDGE CENTERS ACROSS AL AND WEST
GA. MODELS SHOW WESTWARD BUILDING OF ATLANTIC RIDGE INTO SE U.S.
NEXT 48 HOURS...WHILE TX RIDGE WEAKENS AS SECONDARY RIDGE BUILDS
OVER OHIO VALLEY REGION. BY 12Z FRI...LARGE UPPER RIDGE BECOMES
MAIN WEATHER FEATURE FOR SE U.S. TROUGH PRETTY MUCH REMAINS IN
PLACE OVER S AL THROUGH THE PERIOD AND SLOWLY FILLS. ALL THESE
FACTORS POINT TO A RETURN TO MORE NORMAL SUMMERTIME WEATHER FOR GA.
AT THE SURFACE...RICH SURFACE BASED MOISTURE BEGINNING TO CREEP
NORTHWARD. THIS IS CONSISTENT WITH BUILDING UPPER RIDGE AND IS
REFLECTED AT THE SURFACE WITH BUILDING BERMUDA HIGH. LAPS AND
SURFACE ANALYSIS SHOWS 70+ DEWPOINTS HAVE MADE IT AS FAR NORTH AS
THE SOUTHERN SECTIONS OF THE ATL METROPOLITAN AREA.
MEANWHILE...MODELS SHOW MEAN 1000-500MB MOIST AXIS THAT HAS REMAINED
OVER SE SECTIONS OF GA BEGINNING TO WANE AS RIDGE BUILDS WESTWARD
AND MOISTURE CREEPS NORTHWARD. WHILE MOISTURE PLENTIFUL...DOES NOT
APPEAR THAT THERE IS MUCH IN THE WAY OF ANY TRIGGERING MECHANISM FOR
PCPN TONIGHT OR THURSDAY.
NOTED AN INTERESTING FEATURE THAT WILL BEAR WATCHING FRIDAY
EVENING. MRF DEPICTS A WELL DEFINED VORTICITY CENTER ROTATING
AROUND THE SE/S SIDE OF BUILDING OHIO VALLEY/MID-ATLANTIC
RIDGE AT 00Z SAT WHICH WOULD AFFECT N GA. THIS PATTERN IS SIMILAR
TO 7/6/99 WHEN WIDESPREAD SEVERE THUNDERSTORMS AFFECTED N GA. THIS
WILL BEAR WATCHING BY LATER SHIFTS FOR SUCH POTENTIAL.
FOR THE SHORT RANGE...OTHER THAN REMOVAL OF "EVENING" WORDING...FEEL
THAT FORECAST LOW TEMPERATURES MAY BE TOO LOW. DEWPOINTS 70 TO 75
(EVEN 77 AT VLD) NOW ACROSS SOUTHERN TWO-THIRDS OF GA...WITH 65 TO
70 DEWPOINTS NORTHERN ONE-THIRD. CLEARLY COLD AIR WEDGE HAS ERODED
ALL SECTIONS. WILL BUMP UP LOWS ONE-CATEGORY IN MANY AREAS. LOW
AND MID-CLOUDS SHOULD REMAIN PRIMARILY ACROSS SE HALF OF STATE PER
RUC PREDICTIONS. JUST SCT HIGH CLOUDS NW SECTIONS. HOWEVER...IN
THE NW...FOG AND HAZE ARE ONCE AGAIN REDUCING VISIBILITIES AND THIS
SHOULD ONLY GET WORSE OVERNIGHT. WINDS WILL GENERALLY BE LIGHT SE
OR CALM TONIGHT. SE-S FLOW SHOULD CONTINUE FOR SEVERAL DAYS AS IT
APPEARS BERMUDA HIGH IS LOCKED INTO PLACE FOR THE FORESEEABLE FUTURE.
NO CHANGES TO OTHER PERIODS AT THIS TIME.
.ATL...NONE.
RAB
FXUS72 KFFC 141901 ga
STATE FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1010 AM EDT WED JUL 14 1999
AS THE LOW-LEVEL INVERSION OVER NORTH GA ERODES THIS AFTERNOON...
SKIES SHOULD BECOME PARTLY CLOUDY. THIS WILL REQUIRE SOME UPWARD
ADJUSTMENTS TO HIGH TEMPERATURES THERE. BUT OVER THE CENTRAL AND
SOUTH...MOSTLY CLOUDY TO CLOUDY SKIES WILL CONTINUE. THE 8 AM RUC
MODEL RUN INDICATES THAT ANOTHER WAVE DEVELOPS ON THE FRONT IN
SOUTHWEST GA THIS AFTERNOON. ALSO...THE FRONT APPEARS TO BE SHIFTING
SLOWLY NORTHWARD AS THE UPPER LEVEL TROUGH OVER THE SOUTHEAST
RECEDES. THE ZONE UPDATES FOR THIS AFTERNOON WILL SHOW AN INCREASE
IN RAIN CHANCES TO 60 PERCENT SOUTHWEST AND 50 PERCENT CENTRAL.
.ATL...NONE.
SCHAUB
ga
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
930 PM CDT WED JUL 14 1999
UPDATES TO THE FORECAST TO REMOVE THUNDERSTORMS TONIGHT. SHORTWAVE
DROPPING SOUTHEAST THRU NORTHERN WISCONSIN HELPED INCREASE LOW-LEVEL
WARM ADVECTION AND ASSOCIATED WEAK LIFT FOR A TIME THIS AFTERNOON AND
EVENING ACROSS NORTHERN SECTIONS OF THE CWA. SURFACE ANALYSIS SHOWING
WEAK SURFACE BOUNDARY DRAPED FROM MINNEAPOLIS TO ABERDEEN SOUTH
DAKOTA AND ASSOCIATED LOW LEVEL CONVERGENCE...ALL OF THIS NOW LIFTING
NORTHWARD AND WEAKENING. LOOKS LIKE MAIN FOCUS OF ACTIVITY WILL BE
WELL WEST OF THE AREA ACROSS WESTERN DAKOTAS AND NEBRASKA TONIGHT.
MCS DEVELOPING IN EASTERN MONTANA WILL MOVE INTO THE DAKOTAS
OVERNIGHT...BUT WILL NOT AFFECT DES MOINES FORECAST AREA. WILL REMOVE
MENTION OF THUNDERSTORMS FROM TONIGHTS FORECAST.
WRAP AROUND STABLE AIR MOVING NORTHWARD INTO CENTRAL IOWA FROM
MISSOURI PER ETA AND RUC THIS EVENING WILL ALSO MAKE IT DIFFICULT FOR
ACTIVITY MOVING TOWARD OR INTO THE AREA TO SUSTAIN CONVECTION.
.DSM...NONE
TC
FXUS63 KDVN 141948 ia
FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
325 PM CDT WED JUL 14 1999
NOTICE TO USERS...EFFECTIVE THURSDAY JULY 15 1999 AT 1100 AM CDT THE
PRODUCT IDENTIFIER FOR THIS PRODUCT... STATE FORECAST DISCUSSION...
BE CHANGED. THE NEW NWWS ID WILL BE NEWAFDNEW AND THE NEW WMO HEADING
WILL BE FXUS64. THE NEW MASS MEDIA HEADER WILL BE... AREA FORECAST
FORECAST DISCUSSION.
WATER VAPOR LOOPS OVERLAYED WITH RUC ANALYZED VORTICITY SHOW
MID/UPPER TROUGH EXTENDING FROM THE GREAT LAKES/OHIO VALLEY REGION
SW ACROSS CENTRAL AL INTO SE LA. ALSO... A WEAK 500 MB LOW WAS
ANALYZED THIS MORNING NEAR SLIDELL. DRY SUBSIDING AIR WAS NOTED
ACROSS LA/SE MS WHILE MUCH THE REMAINDER WAS IN A POCKET OF HIGHER
MOISTURE AND A MID LEVEL COLD POOL. EVEN WITH THE DRY AIRMASS...
DAYTIME HEATING AND MARGINAL MOISTURE HAS ALLOWED ISOLATED SHOWERS
AND ONE OR TWO THUNDERSTORMS TO FORM ACROSS SE LA AND SW MS.
AT THE SAME TIME...A SHARP INVERTED TROUGH WAS NOTED IN THE TROPICAL
EASTERLIES FROM THE WRN YUCATAN PENINSULA NE INTO THE E CENTRAL
GULF...MOVING STEADILY WEST. SURFACE MAPS SHOW WAS SHOWING HINTS OF
A WARM FRONT FROM EXTENDING ACROSS ERN LA/WRN MS EARLIER TODAY...AND
THERE IS STILL QUITE A LARGE TEMP DISCONTINUITY BETWEEN RAIN COOLED
AIR OVER CENTRAL MS AND AREAS THAT RECEIVED SUN IN SURROUNDING
AREAS. SHALLOW BOUNDARY LAYER MOISTURE HAS MIXED OUT ALLOWING
DEWPOINTS TO DROP INTO THE MID TO UPPER 60S THIS AFTERNOON ACROSS
MUCH OF THE AREA...WHICH WILL PROBABLY ALLOW TEMPS TO DROP A FEW
DEGREES BELOW NORMAL TONIGHT AS SUGGESTED BY MOS.
FOR THE FORECAST...WILL SEE A TRANSITION TO FAIRLY DEEP SOUTHERLY
FLOW AGAIN LATE TONIGHT THROUGH FRI AS UPPER HIGH PRES REPLACES THE
UPPER TROUGH OVER THE GREAT LAKES AND OHIO VALLEY AND GULF TROUGH
MOVES WEST. ANOTHER SEPARATE UPPER HIGH IS FORECAST TO FORM OVER THE
EXTREME NE GULF WHICH WILL HELP STEER EASTERLY WAVE TYPE SYSTEMS
INTO THE WRN/CENTRAL GULF COAST REGION. OVERALL...LIKE THE ETA'S
IDEA OF BRINGING SCATTERED COVERAGE CONVECTION TO THE EXTREME SE
ZONES BY THU AFTERNOON... CONTINUING WITH NORMAL TYPE NOCTURNAL
CONVECTION NEAR THE COAST THU NIGHT...THEN THE CLIMATOLOGICAL HIGH
SCATTERED (40 TO 50 PERCENT) COVERAGE SHOWERS/THUNDERSTORMS ON FRI.
THIS PATTERN WILL LIKELY CARRY ON INTO THE WEEKEND. OVERALL...PREFER
THE SLIGHTLY COOLER AND WETTER AVN MOS NUMBERS. LCH AND SHV AFD
NUMBERS LOOK GOOD FOR THIS FINAL FULL DAY BEFORE ZONE FORECAST/LONG
FUSE WARNING SERVICE TRANSFER.
SHV 72/93/72/92 0001 MLU 71/92/71/91 1001 LCH 72/90/73/90 0113
BTR 70/91/72/89 0214 MCB 68/91/70/91 1214 GPT 73/91/75/89 0325
.NEW...NONE.
LA...NONE.
MS...NONE.
22
FXUS64 KSHV 141940 la
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1000 PM EDT WED JUL 14 1999
LATEST WV LOOP INDICATES FAIRLY VIGOROUS SHRTWV MOVG ESEWD THRU
CNTRL ONTARIO...IN GOOD AGREEMENT WITH MOST CURRENT MODEL FCSTS...
ALG WNWLY FLOW ALF DOWNSTREAM OF MAJOR PAC NW TROF AND RDG AXIS OVR
NRN PLAINS. MODELS INDICATE WRN GRT LKS ARE ON SRN PERIPHERY OF MID LVL
QVECTOR CNVGC ASSOCIATED WITH THIS SHRTWV. 00Z SFC CHART SHOWS CWA
REMAINS IN WARM...MOIST SWLY FLOW ARND HI PRES NR NEW ENGLAND. WARM
FNT LOCATED JUST S OF CWA-WI BORDER...AND SFC DWPTS TO S OF BNDRY AS
HI AS 75 IN NW WI. ALTHOUGH LAPS ANAL SHOWS CAPES AS HI AS 3000-4000
J/KG OVR NW WI IN AREA WHERE LATEST RUC/MESOETA FCST SOME H85-5
QVECTOR CNVGC ON SRN PERIPHERY OF ONTARIO SHRTWV...88D LOOPS
INDICATE TSRA CONFINED TO FAR NW WI S OF LK SUP. THIS AREA AT NOSE
OF H85 THETA-E MAX AND NR INTERSECTION POINT OF WARM FNT...LK BREEZE
BNDRY AND COLD FNT AHD OF DRIER AIR ACRS NRN MN AND ON SRN FLANK OF
NWLY H3 JET MAX ASSOCIATED WITH ONTARIO SHRTWV. TSRA ARE MOVG SLOWLY
ESEWD ALG WARM FNT. STRG CAP/HI MID LVL TEMPS INDICATED ON 00Z
GRB/INL/MPX SDNGS APRNTLY TOO SGNFT FOR THESE DYNAMICS XCPT WHERE
INTERSECTING BNDRYS PROVIDING ENUF LIFT. 00Z GOES SOUNDER CIN SHOWS
-100 J/KG TO BE OVERCOME ACRS WRN CWA (COMPARED TO -2 ACRS FAR NW
WI). ONLY FLAT SC OBSVD OVR CWA LATE THIS AFTN AS WARM AND MOIST
FLOW TRAPPED UNDER CAP. 01Z SFC DWPTS ACRS CWA GENERALLY IN 60S
UNDER SLOWLY DSPTG CU/SC. CONSIDERABLE ANVIL DEBRIS FM NW WI TSRA
MOVG ACRS SW ZNS IN WNWLY FLOW ALF.
MAIN FCST CONCERNS TNGT ARE CHCS FOR SHRA/TSRA. 18Z MESOETA
INDICATES CWA TO REMAIN IN POSITIVE H85 THETA-E ADVCTN OVRNGT AND
THAT DRYING ACRS NRN MN/SW ONTARIO WL NOT REACH FA...IN GOOD
AGREEMENT WITH WEAK SFC FLOW ON COOL SIDE OF BNDRY. BUT H85 FLOW
PROGGED TO WEAKEN AND BCM INCRSGLY ACYC OVRNGT UNDER INCRSG NVA IN
WAKE OF ONTARIO SHRTWV...WHICH ALSO MAINTAINS CAP STRENGTH. SINCE
MSTR INFLOW WL BE WEAKENING OVRNGT AND LK BREEZE BNDRY ALSO APPEARED
INSTRUMENTAL IN POPPING TSRA ACRS NW WI...XPCT CURRENT TSRA TO DSPT
IN NEXT FEW HRS WITH LOSS OF INSOLATION. WL RESTRICT MENTION OF
LINGERING SHRA/TSRA TO FAR SW BORDER ZNS AS CNVCTN CONTS TO DRIFT
ESE NR WARM FNT BEFORE DSPTG. QUICK LOOK AT 88D SHOWS ISOLD TSRA OVR
IRON COUNTY.
ALTHOUGH SFC DWPTS ATTM ARE A BIT HIER THAN FCST MIN TEMPS...LATEST
LAMP GUIDANCE INDICATES TEMPS WL FALL OFF LATER WITH INCRSG DNVA
ALLOWING FOR SKIES TO CLR AND LO LVL FLOW TO BCM WEAKER/MORE ACYC.
XPCT MIN TEMPS A FEW DEGREES LWR THAN CURRENT DWPTS...SO WL KEEP
MENTION OF PTCHY FOG LATE.
.MQT...NONE.
KC
FXUS63 KDTX 150147 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
902 PM EDT WED JUL 14 1999
WILL DO A QUICK UPDATE TO ZONE FORECAST TO REFLECT THE LATEST STLT
AND RADAR TRENDS. WILL LEAVE MENTION OF SHOWERS AND POSSIBLE
THUNDERSTORMS IN THE FORECAST FOR EAST UPPER MICHIGAN AND STRAITS AREA
WITH GENERALLY AFTER MIDNIGHT WORDING. UPPER LEVEL TROF AND VORT MAX
CURRENTLY MOVING OVER WESTERN UPPER... ALREADY BEGINNING TO REDEVELOP
THUNDERSTORMS WEST OF MQT. THE THUNDERSTORMS ARE FIRING IN A RIBBON OF
16C 850 DEW PT AIR AND 850/700 QVECTOR FORCING. THIS AIRMASS AND
FORCING PROGGED BY THE RUC TO CONTINUE MOVING EASTWARD OVER THE UPPER
PENINSULA TONIGHT... AFFECTING SSM AND STRAITS AREA AROUND MIDNIGHT.
FOR THE REST OF THE FORECAST AREA... ONCE CURRENT RAINFALL NOW SOUTH OF
M-72... EXITS SOUTH OF THE FORECAST AREA... WOULD EXPECT GENERALLY
PARTLY CLOUDY SKIES WITH NO PCPN AS BEST 850 MOISTURE POOL AND DYNAMICS
STAY NORTH. WILL LEAVE MENTION OF EVENING SHOWING WITH PARTLY CLOUDY
SKIES OVERNIGHT MOST OF NORTHERN LOWER.
.APX...NONE.
SWR
FXUS63 KMQT 142011 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
857 PM CDT WED JUL 14 1999
EVENING SURFACE ANALYSIS CONTINUES TO SHOW FRONTAL BOUNDARY PARKED
ON A LINE FROM NEAR DLH TO HON. ADAP CHARTS SHOW MAIN FOCUS ON THE
LOW LEVEL CONVERGENCE OVER CENTRAL SD WITH ANOTHER AREA OVER
NORTHERN WI. THIS PLACES SOUTHERN MN IN A RATHER DIFLUENT LOW LEVEL
FLOW. BEST H8-H3 THICKNESS DIFLUENCE IS OVER NORTHERN WI THROUGH
15/06Z. 00Z RUC ALSO SHOWING THE 500 MB SHORT WAVE AT 00Z EXTENDING
FROM WESTERN LSUP TO CENTRAL MN. KMPX RAOB RATHER DRY ABOVE 800 MB
WITH QUITE A BIT OF WESTERLY FLOW NOTED BETWEEN 800 AND 500 MB.
RUC/MESO-ETA/ETA RUNS ALL POINT TO STRONG THETA-E ADVECTION
DEVELOPING ACROSS SD THIS EVENING AND SPREADING INTO ND OVERNIGHT
WITH AN EXTENSION SE INTO CENTRAL MN. 700 MB RIDGING ALSO INCREASES
OVER THE CWA WITH TEMPERATURES OVER THE WESTERN AND SOUTHERN
SECTIONS BETWEEN 12 AND 14 DEG C. IN SUMMARY...WILL REMOVE
THUNDERSTORMS OVERNIGHT ALONG AND SOUTH OF A LINE FROM MONTEVIDEO TO
MINNEAPOLIS TO EAU CLAIRE DUE TO MORE STABILITY. WILL KEEP A SMALL
POP TO THE NORTH OF THIS LINE AS THE FRONTAL BOUNDARY BECOMES MORE
E-W ORIENTED DURING THE NIGHT.
.MSP...NONE.
HILTBRAND
FXUS63 KDLH 142028 mn
FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
840 AM CDT WED JUL 14 1999
A POCKET OF INSTABILITY AND LOW LEVEL WARM ADVECTION ARE COMBINING
WITH A RETURNING WARM FRONT TO PRODUCE A SMALL AREA OF SHOWERS AND
THUNDERSTORMS OVER W CENTRAL MS. THE 09Z RUC SEEMS TO MOVE THE
ASSOCIATED MOISTURE POOL SEWD THROUGH EARLY AFTERNOON WHILE
GRADUALLY DRYING IT UP. HAVE UPDATED THE W CENTRAL ZONES TO REFLECT
THE SHOWERS BY ADDING A MORNING GROUP - HOPEFULLY THIS FLY IN THE
OINTMENT WILL DIE QUIETLY THIS AFTERNOON.
QPF DISCUSSION: LOOK FOR AMOUNTS OF ONE QUARTER TO ONE HALF INCH IN
THE UPDATED AREA AS RADAR CURRENTLY INDICATING A FEW PIXELS OF MORE
THAN ONE INCH JUST NW OF KTVR. WILL AMEND QPF FORECAST FOR FIRST
SIX HOURS IN THE UPDATED AREA.
.JAN...
MS...NONE.
LA...NONE.
AR...NONE.
ms
MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
915 AM PDT WED JUL 14 1999
SYNOPSIS...A MOIST AND UNSTABLE AIRMASS WILL REMAIN OVER MOST OF THE
REGION TODAY. AN UPPER LEVEL DISTURBANCE OVER SOUTHERN NEVADA WILL
HELP TRIGGER SHOWERS AND THUNDERSTORMS THROUGH THIS EVENING. A DRIER
SOUTHWEST FLOW WILL MOVE INTO THE REGION THURSDAY...PUSHING MUCH OF
THE MOIST AIR OFF TO THE EAST WITH ONLY ISOLATED AFTERNOON
THUNDERSTORMS EXPECTED.
DISCUSSION...UPPER CIRCULATION SEEN NICELY ON VISIBLE SATELLITE
IMAGERY OVER SWRN LINCOLN COUNTY MOVING STEADILY EWD. 12Z RUC
DEPICTED THIS NICELY ON ITS 3HR FORECAST. THE RUC SHOWS THE MAIN
VORTICITY CENTER MOVING OFF INTO SWRN UT BY 00Z WITH ANOTHER WEAKER
CENTER DEVELOPING AND MOVING INTO EXTREME NRN CLARK COUNTY DURING THE
SAME TIME PERIOD. THE NEW RUC IS SLIGHTLY DIFFERENT AND SEEMS TO HAVE
A POOR INITIAL PANEL ON THE MAIN VORT CENTER. IT TAKES THE CENTER
FARTHER S INTO NCNTRL AZ BY 03Z WITH THE SECONDARY CENTER INTO
EXTREME NWRN MOHAVE COUNTY BY 03Z. THIS SEEMS TO BE ON ONLY FOCUS FOR
THIS AFTERNOON AND EVENING ALONG WITH GENERAL ISENTROPIC UPGLIDE
ACROSS THE ENTIRE AREA THIS AFTERNOON AND EVENING. BETTER SHEAR TODAY
AS NW FLOW TO 30KTS AT H5 DEVELOPS AND S TO SW FLOW AT SURFACE AND
850MBS AROUND 15KTS. STORMS SHOULD MOVE FAIRLY QUICKLY TODAY IN MOST
AREAS. FLASH FLOOD WATCH STILL OK FOR NWRN AZ AS MID LEVEL TROUGH
AXIS SHOULD BE RUNNING THROUGH THAT AREA THIS AFTERNOON BUT WILL HAVE
TO RELY ON TRAINING OR JUST VERY STRONG STORMS TO PRODUCE FLOODING.
FOR LAS VEGAS VALLEY...STORMS SHOULD FORM OVER THE SPRING MOUNTAINS
LATER THIS MORNING AND ROLL THROUGH THE CITY DURING THE AFTERNOON.
AFTERNOON CAPES BETWEEN 1000 AND 2000 J/KG AND LIFTED INDICES TO
MINUS 4 OR 5 SHOULD PROVIDE PLENTY OF INSTABILITY. EVEN THOUGH NO
FLASH FLOOD WATCH WILL BE ISSUED ATTM FOR THE VALLEY WILL HAVE TO
KEEP AN EYE ON STORM DEVELOPMENT AS FEW COULD BE QUITE STRONG BUT
WITH OVERALL EWD MOVEMENT OF 15 TO 20 MPH. NO UPDATES PLANNED AS OF
NOW. SKRBAC
.LAS...A FLASH FLOOD WATCH HAS BEEN ISSUED. PLEASE REFER TO THE
LATEST RNOFFALAS STATEMENT FOR DETAILS.
FXUS65 KREV 141603 nv
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
938 AM EDT WED JUL 14 1999
S/WV SLOWLY ROTATING INTO THE MID ATLC REGION IS PROGGED BY THE 09Z
RUC TO CONT MOVE SLOWLY NE AND AWAY FROM THE FA. BEST LIFT FROM
THIS FEATURE SHOULD BE OVER CENTRAL NC TO THE N WITH ONLY WEAK LIFT
PROGGED ACROSS THE FA. LATEST MSAS SFC ANALYSIS SHOWS TO AREAS OF
WEAK LOW PRES NEAR THE VICINITY OF THE OLD FNT. ONE OVER NE NC WILL
CONT AWAY FROM THE AREA WHILE THE SECOND IN THE VICINITY OF FAY IS
HELPING TO ENHANCE RAIN AREA FOR INLAND SECTIONS. THE OLD FRONT HAS
SHIFTED JUST OFF THE COAST THIS MORNING. 09Z RUC INDICATES THE FNT
SHOULD DRIFT INLAND AGAIN THIS AFTN. WITH THE FNT IN THE AREA AND
SOME MOISTURE CONV PROGGED TO OCCUR ALONG IT WILL CONT POPS AS IS
FOR THE AFTN. VIS SATL IS SHOWING A FEW BREAKS IN THE CLOUD COVER
ALONG THE COAST SO WILL GO WITH M/CLOUDY FOR ALL THE COASTAL
REGION. NOT MUCH TEMP RISE EXPECTED WITH THE EXTENSIVE CLOUD COVER
SO CURRENT TEMP FCSTS LOOK REASONABLE.
CWF: CURRENT FCST LOOKS TO HAVE A GOOD HANDLE ON THE PLACEMENT OF
THE FRONT. ONLY PLANNED CHANGES ARE TO THE NC WATERS. ESTIMATED 10
METER WIND FROM FPSN7 IS ONLY 7KT AT 13Z SO WILL LOWER WIND SPEEDS
AND SEAS AND COMBINE ALL ZONES INTO ONE GROUP.
.ILM...NONE.
IRELAND
nc
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
905 PM CDT WED JUL 14 1999
NO UPDATE PLANNED. WEAK HIGH PRESSURE OVR NRN RRV IS SLOWLY DRIFTING
EAST ALG THE NRN MN BORDER...WELL HANDELED BY 12Z MODEL SUITE. NRLY
FLOW INTO FGF CWA HAS STABILIZED LOW LEVELS FOR THE EVENING. LATE
TONIGHT AND TOWARDS MORNING...STILL EXPECT TSTM DEVELOPMENT INTO
AREA. LOW LVL MOISTURE ADVECTION HAS INTENSIFIED LAST FEW HOURS INTO
CNTRL SD WITH A TIGHT INSTABILITY GRADIENT FROM HON NWD TO THE ND
BDR. 00Z RUC PUSHES MOISTURE CONVERGENCE ZONE INO SCNTRL ND BY 06Z
AND INTO NRN RRV BY 12Z...WITH ACCOMPANYING WARM FRONTAL SURGE.
CURRENT TEMPS AND PCPN TIMING ARE GOOD.
.FGF...NONE.
GUST
FXUS63 KBIS 142038 nd
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
952 AM CDT WED JUL 14 1999
...CLOUD COVER/-TSRA CHANCE SE FORECAST CONCERNS THIS AFTN...
AREA OF LOW CLOUD ON VIS PIC THIS AM INDICATES THIS HANGING ALONG
WEAK TROF LINE SEPARATING NORTH SFC FLO FROM EAST. PRES RISES
SINKING INTO CENTRAL ND PER MSAS SHOULD ALLOW CLOUD MASS/TROF TO
CONTINUE MOVING SLOWLY S THRU AFTN. BEHIND TROF IS TEMPORARY AREA OF
MORE STABILILTY (RUC FORECASTING LI/S TO JUMP ABOVE ZERO WEST OF RRV
BY LATE AFTN) AS MID/UPPER LEVEL RIDGE CRESTS OVER CWA IN RESPONSE
TO U/L LOW DIGGING IN PAC NW. NVA SPREADING IN ALONG WITH ADVECTION
OF SLIGHTLY LOWER TD/S FROM MB/CENTRAL SHOULD INHIBIT COVENCTIVE
CHANCE MUCH OF CWA EVEN AFTER SFC HEATING COMMENCES WHEN CLOUDS MOVE
OUT.
ONE CONCERN WOULD BE SE CWA WHERE POOL OF TD/S NEAR 70F EXIST AND
HEATING ONGOING. AS WEAK SFC LO NOW OVER NE SD MOVES EAST...SOME LOW
LEVEL CONVERGENCE WILL SWING INTO SCNTRL MN ALTHO UPPER SUPPORT
LACKING WITH JET SHIFTING BACK TO THE NW OVER SASK. MODEL SOUNDINGS
FOR THAT AREA DO KEEP LI/S NEAR -6 THIS AFTN...WITH WITH CAPES OVER
2000 J/KG. H7 TEMPS WARM TO NEAR +12C UNDER RIDGE BUT BEST CAPPING
INVERSION PROBABLY JUST SOUTH OF CWA BORDER. WIND PROFILE VERY WEAK
UP THRU 7KFT AND SHEAR NOT IMPRESSIVE...SO NOT LOOKING FOR ORGANIZED
STORMS BUT ANY THAT DO FORM COULD BECOME SEVERE WITH JUICE IN PLACE
AND WEAKENING BOUNDARY NEAR.
WILL CHANGE WORDING FOR SW CWA TO ACCOUNT FOR CLOUDS MOVING THRU AND
ADD CHANCE -TSRA SE ZONES FOR AFTN UPDATE. THINKING OF LOWERING
TEMPS JUST A TAD N/NW ZONES WITH THE WEAK CAA INTRUSION AND CLOUD
COVER THIS AM HOLDING NUMBERS DOWN SLIGHTLY.
.FGF...NONE.
SOROKA
FXUS63 KFGF 140900 AMD nd
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
848 PM EDT WED JUL 14 1999
RUC SHOWS SHORTWAVE IN WESTERLIES MOVING SLOWLY ACROSS OH VALLEY
TONIGHT. NC MOUNTAINS TO COME UNDER PVA AFTER 06Z. VERY LIGHT
SHOWERS PERSISTING NEAR TN BORDER AND BLUE RIDGE PER KGSP RADAR.
WILL MAINTAIN LOW POPS NC MOUNTAINS. DEW POINTS CREEPING UP IN
SAVANNAH RIVER VALLEY. LOSS OF DAYTIME HEATING AND LATE ARRIVAL
OF OH VALLEY WAVE NOT FAVORABLE FOR CONVECTION SC/GA OR NC
PIEDMONT. WILL DROP POPS METRO CLT. TEMPERATURES SHOULD BE A
CATEGORY HIGHER THAN LAST NIGHT WITH WITH MORE MOISTURE. CURRENT
FORECAST MINIMUMS APPEAR ON TRACK. MOISTURE SHOULD LEAD TO MORE
FOG AS WELL THOUGH WINDS STILL UP A BIT.
.GSP...NONE.
JAT
FXUS62 KCAE 141853 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1015 AM EDT WED JUL 14 1999
SATELLITE IMAGERY SHOWS THE WESTERN EDGE OF THE THICKER CLOUD COVER
CORRESPONDING NICELY TO THE AXIS OF THE UPPER JET THIS MORNING. THE JET
AXIS SHOULD CONTINUE TO SHIFT GRADUALLY EAST THIS AFTERNOON. WATER VAPOR
IMAGERY ALSO SHOWS A VORT MAX OVER THE WESTERN CAROLINAS...WHICH THE
09Z RUC AND 03Z ETA MOVE AWAY TO THE NORTHEAST THIS AFTERNOON. AS A
RESULT...THE MAJORITY OF THE FCST AREA SHOULD BE UNDER A REGION OF WEAK
SUBSIDENCE BEHIND THE VORT CENTER AND IN THE LEFT ENTRANCE REGION OF
THE JET. MODIFYING THE RAOB FROM FFC YIELDS MINIMAL CAPE AROUND 500
J/KG OWING TO A WARM LAYER AT MID LEVELS. ALTHO THE 03Z ETA SHOWS A
MODEL CAPE OF AROUND 1000 J/KG ACROSS PARTS OF THE UPSTATE THIS
AFTERNOON...BELIEVE THIS IS OVERDONE AS THE ETA ALSO BRINGS SURFACE
DEWPOINTS BACK UP TO AROUND 70 DEGREES F...WHICH LOOKS TOO HIGH. THIS
LEADS ME TO BELIEVE THAT PRECIP CHANCES ARE MINIMAL ACROSS MOST OF THE
FORECAST AREA THIS AFTERNOON. THE 03Z ETA DOES SHOW A CENTER OF
MOISTURE FLUX CONVERGENCE AT LOW LEVELS ACROSS THE MOUNTAINS THIS
AFTERNOON...BUT THAT COULD ALSO BE ASSOCIATED WITH THE QUESTIONABLE
SURFACE DEWPOINTS. AGREE WITH MRX THAT 09Z RUC QPF IS OVERDONE ACROSS
THE MOUNTAINS THIS AFTERNOON. WILL KEEP A SMALL PRECIP CHANCE IN THE
MOUNTAINS...AND ALONG THE EASTERN EDGE OF THE FCST AREA WHICH REMAINS
ON THE RIGHT SIDE OF THE JET. HOWEVER...WILL MAKE A BOLD MOVE AND
ELIMINATE PRECIP CHANCE ACROSS THE FOOTHILLS AND MOST OF UPSTATE SC.
THE DEATH OF THE WEDGE MAKES THE TEMP FORECAST TRICKY. SINCE I LACK ANY
NEW INSIGHT...WILL LEAVE TEMPS ALONE.
.GSP...NONE.
MOORE
FXUS62 KCHS 141403 sc
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
332 PM CDT WED JUL 14 1999
HIGH BASED TSRA DANCING THRU CWA THROUGH ERLY AFTN...WELL ABV SIG
LOW LVL CAP...AND WITH CONSIDERABLY LESS INSTABILITY / 1-1.5KJ/KG /
THAN ANY SURFACE BASED...EVAPOTRANSPIRATICALLY ENHANCED...PARCEL.
MAIN BULK OF TSRA FORMED ON LEADING EDGE OF SUBTROP MSTR PLUME
COMING AROUND CNTRL US RIDGE...WITH A SIGNIFICANT SUBTROPCIAL WAVE
LIFTING AROUND RIDGE INTO CNTRL UT ATTM...SQUEEZING AHEAD OF MAIN
WRLY FLOW CIRC IN BRITISH COLUMBIA.
SUBTLETIES WILL BE THE RULE FOR THIS FCST. OVERALL...ETA BLEND WITH
AVN SEEMS TO BE IN ORDER. ETA LTL STG TO INITIAL LEE SIDE DVLPMT
TDA. NOT TOO PLEASED WITH ANY MDL HANDLING OF SHORT RANGE
FEATURES...EVEN RUC. SEEMS THAT MID LVL MSTR PLUME HAS FALLED
BETWEEN THE CRACKS IN GUIDANCE...THEREFORE UNDERESTIMATING THE
POTENTIAL FOR ELEVATED CONVECTION TONIGHT. STLT SOUNDINGS TO THE
RESCUE...AND POTENTIAL CORRECTLY CAPTURED WITH PROGGED BASES ABV
12K. 18Z RUC DOES ADVERTISE AN E TO W THETA E RIDGE ABV CAP...
COLLOCATED WITH AN AXIS OF ELEVATED INSTABILITY...ACRS CWA AND
LIFTING SLOWLY NWRD THRU 06Z. WHILE THREAT THRU SERN CWA SEEMS
MINIMAL...CANNOT IGNORE CURRENT HAPPENINGS...AND WL CARRY A LOW POP
EARLY.
DEEPENING LOW TO NW WL HELP TO PULL SOME WARMER MID LVL AIR INTO MIX
LTR TNGT AND INTO THU AFTN. AFTER THREAT OF SOME ELEVATED ACTION
N ON LEADING EDGE WARMING WITH LLJ...SHOULD QUIET DOWN UNTIL SIG
SUBTROP WAVE ENCROACHES FM W. JET LIFT BECOMES MUCH MORE FAVORABLE
BY 00Z...AND WL COMPROMISE A BIT BTWN FASTER AVN/SLOWER ETA. POOLING
OF INSTABILITY...AND SIG COOLING OF TMPS AROUND CAP LVL FCST BY 00Z
WOULD MAKE ONE BELIVE THAT A SIG CONVECTIVE EVENT COULD INITIATE ARND
JAMES RVR LATE IN DAY. NOT TERRIBLY IMPRESSED BY SHEAR...BUT INSTABILITY
AND STRENGTH OF MID LVL FLOW SHUD BRING CHC OF FEW STORMS TO BECOME
SVR THU NGT...ESPLY WITH EARLY AND MORE ISOLATED DEVELOPMENTS MORE
CONCERN WOULD BE WITH THREAT OF HEAVIER RAINFALL AS BNDRY WL BE QUITE
SLOW MOVING...AND PWATS OVER 1.25 IN.
FNT CONTINUES TO BE SLOWER AND SLOWER WITH EACH RUN...AND LTST AVN WHILE
TOO SLOW...DOENST EVEN GET FRONT MUCH PAST 12Z/16 ETA POSN BY 00Z/17.
WL PLAY ANOTHER WARM AND MUGGY DAY...WITH LINGERING CHC TSRA.
EXTENDED RANGE...OVERALL...AFTER SHORT RANGE TROUGH FLATTENS RIDGE
SOMEWHAT...SEE AGREEMENT AT LEAST ON REBUILDING RIDGE BACK TO W WITH
SLIGHT RETROGRESSION FM POSITION EARLY IN WEEKEND. HTS REMAIN RELATIVELY
HIGH AND WL HAVE A FAVORABLE JET/FRONT CONFIGURATION FOR PCPN THROUGHOUT
THE PERIOD AS LOW LVL SRLY FLOW IMPINGES ON BNDRY...ESPLY SAT NGT AND
AGAIN DURG MON. PERIOD LEAST LIKELY FOR PCPN APPRS TO BE MUCH OF
LTR SUNDAY. FOR NOW...WATCH OUT FOR THE SPLATTER...FOR THE BROAD
BRUSH WILL RULE. NATIONAL GUIDANCE LTL HELP...AS IS REGURGITATION OF
FMR OUTPUT...AGAIN.
.FSD...NONE
CHAPMAN
FXUS63 KABR 142021 AMD sd
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE MORRISTOWN TN
943 AM EDT WED JUL 14 1999
KMRX 88D INDICATE MAINLY LIGHT ISOLATED SHOWERS IN NORTHEAST
TENNESSEE THIS MORNING...AND A NARROW BROKEN BAND OF PRECIPITATION IN
THE CUMBERLAND PLATEAU (ALSO IDENTIFIED BY KHTX 88D). 12Z MSAS
DEPICTION CONTINUES TO REVEAL WEAK TROUGH OF LOW PRESSURE IN THE
WESTERN CWA INTO CENTRAL TENNESSEE (WELL CORRELATED WITH MOISTURE
AXIS)...AND HIGH PRESSURE CIRCULATION EVIDENT FARTHER SOUTHEAST
(CENTER OF CIRCULATION NEAR NORTHEAST GEORGIA/NORTHWEST SOUTH
CAROLINA).
IN TERM OF THE LATEST MODEL DATA...09Z RUC AND 03Z MESO-ETA SHIFT
H5 DISTURBANCE IN NORTHWEST FLOW INTO SOUTHERN OHIO VALLEY THIS
AFTERNOON. BOTH MODELS HALT SURFACE PRESSURE RISES FOR THIS
AFTERNOON...PREVIOUSLY ADVERTISED BY EARLIER SYNOPTIC MODELS.
LOW-LAYER OMEGA FIELDS NOT IMPRESSIVE WITH APPROACHING H5 SYSTEM...
AND FEEL THAT 09Z RUC QPF OVERDONE. ALSO...H10/5 MOISTURE PROGS
CONTINUE TO SHIFT SLIGHTLY DRIER AIR IN...MORE SIGNIFICANTLY SO IN
THE SOUTHERN CWA.
THUS...A ZONE UPDATE WILL INTRODUCE OR INCREASE POPS NORTH CWA TO 30
PERCENT...20 PERCENT CENTRAL AND SOUTH FOR THIS AFTERNOON. MOSTLY
CLOUDY ALL BUT SOUTHERN TENNESSEE VALLEY AND SOUTHERN CUMBERLAND
PLATEAU...WHERE BECOMING PARTLY CLOUDY IS A GOOD COMPROMISE.
FURTHERMORE...WILL LOWER MAXES SOME...PARTICULARLY IN THE NORTHERN
CWA WHERE TEMPERATURES NOT EXPECTED TO REACH 80.
DM
FXUS64 KMRX 141343 tn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
943 AM EDT WED JUL 14 1999
KMRX 88D/S INDICATE MAINLY LIGHT ISOLATED SHOWERS IN NORTHEAST
TENNESSEE THIS MORNING...AND A NARROW BROKEN BAND OF PRECIPITATION IN
THE CUMBERLAND PLATEAU (ALSO IDENTIFIED BY KHTX 88D). 12Z MSAS
DEPICTION CONTINUES TO REVEAL WEAK TROUGH OF LOW PRESSURE IN THE
WESTERN CWA INTO CENTRAL TENNESSEE (WELL CORRELATED WITH MOISTURE
AXIS)...AND HIGH PRESSURE CIRCULATION EVIDENT FARTHER SOUTHEAST
(CENTER OF CIRCULATION NEAR NORTHEAST GEORGIA/NORTHWEST SOUTH
CAROLINA).
IN TERM OF THE LATEST MODEL DATA...09Z RUC AND 03Z MESO-ETA SHIFT
H5 DISTURBANCE IN NORTHWEST FLOW INTO SOUTHERN OHIO VALLEY THIS
AFTERNOON. BOTH MODELS HALT SURFACE PRESSURE RISES FOR THIS
AFTERNOON...PREVIOUSLY ADVERTISED BY EARLIER SYNOPTIC MODELS.
LOW-LAYER OMEGA FIELDS NOT IMPRESSIVE WITH APPROACHING H5 SYSTEM...
AND FEEL THAT 09Z RUC QPF OVERDONE. ALSO...H10/5 MOISTURE PROGS
CONTINUE TO SHIFT SLIGHTLY DRIER AIR IN...MAINLY IN THE SOUTHERN
CWA.
THUS...A ZONE UPDATE WILL INTRODUCE OR INCREASE POPS NORTH CWA TO 30
PERCENT...20 PERCENT CENTRAL AND SOUTH FOR THIS AFTERNOON. MOSTLY
CLOUDY ALL BUT SOUTHERN TENNESSEE VALLEY AND SOUTHERN CUMBERLAND
PLATEAU...WHERE BECOMING PARTLY CLOUDY IS A GOOD COMPROMISE.
FURTHERMORE...WILL LOWER MAXES SOME...PARTICULARLY IN THE NORTHERN
CWA WHERE TEMPERATURES NOT EXPECTED TO REACH 80.
DM
tn
TEXAS/OKLAHOMA PANHANDLES AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE AMARILLO TX
1037 PM CDT WED JUL 14 1999
SFC TROUGH REMAINING STATIONARY IN ERN NM WITH SSE WINDS ACROSS THE
PNHDLS. LATEST RUC/NGM/ETA FCSTG TROUGH TO GRADUALLY SHIFT EAST INTO
WRN PART OF PNHDL BY DAYBREAK. THEREFORE...WILL UPDATE ZONES TO BACK
WINDS AROUND TO S IN THE WEST AND S TO SE IN CNTRL AND ERN ZONES.
.AMA...
TX...NONE.
OK...NONE.
JH
FXUS64 KCRP 150236 AMD tx
UTAH AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UTAH
930 AM MDT WED JUL 14 1999
SYNOPSIS...TROPICAL MOISTURE WILL COVER MOST OF UTAH TODAY FOR
WIDESPREAD SHOWERS AND THUNDERSTORMS...SOME WITH HEAVY RAIN. A COLD
FRONT WILL PUSH INTO UTAH TONIGHT THEN STALL OVER THE NORTH PORTION.
DRY AND SOMEWHAT COOLER WEATHER WILL BE NORTH OF THE FRONT THURSDAY
WHILE SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO THE SOUTH.
DISCUSSION...TWO SHORT WAVES TO AFFECT CWFA TODAY. BOTH BEST
CORRESPOND TO 12Z RUN OF RUC WITH 300MB VORTICITY. ONE EAST OF RNO
TO MOVE INTO NORTHWEST UTAH BY 00Z. ONE IN SOUTHWEST UTAH TO SWEEP
ACROSS STATE AND BE NEAR VEL BY 00Z. BOTH PROMISE TO LIFT MOIST
AIRMASS AND MAKE FOR ACTIVE DAY.
SLC 771 CDC 853
.SLC...FLASH FLOOD WATCH NOON TIL 8PM MOST OF CFWA EXCEPT NW AND SW
CORNERS.
FXUS65 KSLC 140956 ut
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
857 PM EDT WED JUL 14 1999
FEW SHRA ALONG THE WRN RIDGES HAVE FADED PER LOSS OF HEATING WITH
LAST VIS PICS INDICATING LOTS OF BREAKS IN LOW DECK ACRS WVA/VA
ATTM. EVE RAOBS SHOW PLENTY OF LOW LVL RH REMAINING HOWEVER...AND
QUEST OVRNGT IS HOW EXTENSIVE LOW CLDNS AND FOG/-DZ WILL BE TOWARD
MORN. ALTHOUGH BREAKS MAY ALLOW BETTER COOLING TOWARD
SATURATION...SLGTLY DRIER DEWPTS SEEN ACROSS THE FAR WEST/NORTH
SHOULD ACT TO LIMIT CVRG THERE A BIT. ELSW...WILL LKLY SEE FILLING
IN OF CLDNS GIVEN LGT ELY TRAJ AND LINGERING COOL WEDGE. OTRW FOG
STAB NUMBERS OFF RAOBS ALSO NOT TOO IMPRES FOR MORE THAN PTCHY FOG
AND LTL -DZ. EXCEPTION NW NC WHERE CONTG LGT UPSLOPE WILL KEEP MORE
LOW LVL MOISTURE IN PLACE PER LATEST RUC BLYR RH/FCST RAOBS. PLAN TO
TWEAK SKY COVER TO MORE PC FLAVOR NRN TIER AND REMOVE MENTION OF
POPS ELSW OVRNGT...OTRW MAINLY CLDY WITH SOME FOG RE-DVLPG. WILL
ALSO ADJUST THU PRD FOR MORE SUN PTNL GIVEN LACK OF DEEP RH BUT CONT
SHRA THREAT WITH WEAK VORT AND HEATING OF SFC RH. MAY LOWER TEMPS A
NOTCH TNGT PER SOME CLRG EARLY AND BUMP UP IN SPOTS THU.
.RNK...
VA...NONE.
NC...NONE.
WV...NONE.
JH
FXUS61 KAKQ 141911 va
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
340 AM CDT WED JUL 14 1999
MAIN FORECAST CONCERNS ARE SHRA/TSRA CHANCES THRU THE PERIOD.
07Z SURFACE ANALYSIS HAD A LOW IN NORTHCENTRAL SD WITH A WARM FRONT
EAST INTO CENTRAL WI. SHRA/TSRA WERE MOVING EAST ACROSS THE NORTH HALF
OF THE FORECAST AREA ALONG THE FRONT...IN AN AREA OF DECENT MOISTURE
ADVECTION/LIFT ON THE 305-310K ISENTROPIC SURFACES. 00Z ETA AND 03Z RUC
DEPICT THIS VERY WELL. THE COLD FRONT WITH THE LOW REMAINED IN SOUTHWEST
ONTARIO TO CENTRAL SD. MOISTURE CONTINUED TO POOL AHEAD OF THE COLD
FRONT AND ALONG THE WARM FRONT...WITH THE BEST INSTABILITY EARLY THIS
MORNING ACROSS EAST CENTRAL MN AND NORTHWEST WI.
00Z MODELS LOOK TO HAVE INITNIALIZED WELL AND ARE IN REASONABLE
AGREEMENT THRU 48HRS...THOUGH THEY DIFFER ON THEIR QPF FIELDS. NGM
DOING BEST WITH QPF THIS MORNING...ETA WITH BEST DEPICTION OF LOWER AND
MID LEVEL FORCING/LIFTING.
WEAK SHORTWAVES IN THE WEST/NORTHWEST FLOW ALOFT MOVE EAST OF THE AREA
BY 12Z. HOWEVER A WEAK 5H TROUGH IS FORECAST TO REMAIN ACROSS WI INTO
SOUTHEAST MN AS A SHORTWAVE RIDGE BUILDS ALONG THE MN/DAKOTAS BORDER IN
ADVANCE OF THE STRONG UPPER LOW DROPPING INTO THE NORTHWEST U.S.
00Z ETA/NGM INDICATE 850-700MB Q-G FORCING...WARM ADVECTION AND
MOISTURE ADVECTION TO CONTINUE ACROSS MUCH OF THE FORECAST AREA TODAY
INTO THIS EVENING. AS DIURNAL HEATING DESTABILIZES THE AIRMASS...
APPEARS A LEAST A CHANCE OF AFTERNOON/EVENING SHRA/TSRA IN ORDER FOR
THE FORECAST AREA. QUESTION IS STRENGTH OF 7H CAPPING FOR LATER TODAY.
CAP LOOKS STRONGEST TO THE SOUTH ACROSS IA/IL AND MARGINAL ACROSS
SOUTHERN MN/CENTAL WI.
WITH ONGOING CONVECTION IN THE AREA THIS MORNING...AND CONVECTION
ACROSS MUCH OF THE AREA THE PAST 24HRS...WILL RAISE POPS INTO SLIGHT
CHANCE/CHANCE CATEGORIES FOR TODAY/TONIGHT. RIDGING/CAPPING SHOULD BE
IN PLACE FOR THU WITH A WARM...DRY DAY EXPECTED AS THE COLD FRONT
REMAINS WELL WEST OF THE AREA UNTIL THU NIGHT. FORCING FOR MCS WED
NIGHT IS ALONG ND/SD BORDER...WITH LIKELY EASTWARD MOVEMENT. WILL LET
DAY SHIFT LOOK AT LATER MODEL RUNS FOR POSSIBLE CHANCE TSRA IN THE AREA
LATE WED NIGHT/EARLY THU MORNING.
NGM-FWC/AVN-FAN TEMP GUIDANCE RATHER SIMILAR THRU THE PERIOD AND
ACCEPTED...TEMP GUIDANCE HAS BEEN TOUGH TO BEAT THE PAST FEW DAYS.
COORDINATED WITH KDVN.
.LSE...NONE.
RRS
wi
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
218 AM MST THU JUL 15 1999
SYNOPSIS...HIGH PRESSURE DEVELOPING SOUTH OF ARIZONA WILL SLOWLY
FEED DRIER AIR INTO THE REGION. HOWEVER...ANOTHER ROUND OF SCATTERED
THUNDERSTORMS CAN BE EXPECTED THIS AFTERNOON AND EVENING. WITH
PLENTY OF MOISTURE STILL AROUND...A FEW STORMS COULD ONCE AGAIN
PRODUCE HEAVY DOWNPOURS. THE HIGH PRESSURE AREA WILL GRADUALLY
MIGRATE INTO THE SOUTHERN PLAINS OVER THE WEEKEND. WHILE THIS STILL
FAVORS MONSOON THUNDERSTORMS...THE ACTIVITY WILL NOT BE AS
WIDESPREAD AS IT HAS BEEN RECENTLY.
DISCUSSION...WESTERLY FLOW HAS COMMENCED, BUT WE'RE NOT OUT OF THE
WOODS YET (OR TROPICAL RAIN FOREST AS THE CASE MAY BE). A SLEEPER
SHORT WAVE IN THE KLAS AREA, WHICH IS FUELING A SMALL, SLOW-MOVING
MCS NEAK KIGM, WAS ONLY PICKED UP WELL BY THE ETA AND RUC. THEY TAKE
IT ACROSS NORTHERN AZ TODAY WITH A TRAILING, WEAK LOBE THROUGH SE AZ
JUST AFTER 00Z. BASED ON CURRENT MOVEMENT, THAT MAY NOT BE TOO BAD.
FLOW AND SHEAR PROFILES AREN'T AS STRONG AS YESTERDAY, SO THE DEGREE
OF RELOADING IS IN DOUBT. HOWEVER, DEEP TROPICAL MOISTURE REMAINS
(PRECIP WATERS IN THE 1.5-1.75" RANGE) WITH SOME MID LEVEL COOLING
EXPECTED. THERE WILL ALSO BE SOME UPPER DIVERGENCE BETWEEN THE VORT
AND THE 300MB HIGH TO OUR SOUTH. THIS MAY EXPLAIN THE ONGOING
CONVECTION ALONG OUR SOUTHERN BORDER AND ISOLATED ELEVATED SHOWERS
AS FAR NORTH AS PINAL COUNTY. THE SLOW DRYING MAY BE JUST ENOUGH TO
KEEP OUR FLASH FLOOD THREAT DOWN, BUT DAY SHIFT WILL HAVE TO WATCH
AND MAY NEED TO BEEF UP WORDING ONCE WE GET THE 12Z UPPER AIR DATA.
THE TORRENTIAL RAIN OVER THE NORTH AND EAST CWA LAST NIGHT HAS
REALLY SATURATED THINGS WITH MANY WASHES STILL RUNNING THIS MORNING.
TO SUM UP, PREVIOUS FORECAST IS IN GOOD SHAPE OTHER THAN A DOWNWARD
TWEAK ON HIGHS TODAY AND SLIGHT POP INCREASES FROM TUCSON EAST THIS
AFTERNOON/EVENING. TOMORROW DEFINITELY LOOKS LIKE A DOWNER WITH
LOWER THETA-E AND SOME WARMING ALOFT. WEAK FLOW SHOULD KEEP MUCH OF
THE ACTIVITY NEAR THE MOUNTAINS WITH A SLIGHT WARMUP DUE TO LESS
CLOUD COVER. NO MRF AVAILABLE AS YET, BUT OTHER MEDIUM RANGE MODELS
MAINTAIN A TROUGH JUST OFF THE WEST COAST. THAT SUPPORTS OUR CURRENT
EXTENDED WITH ONLY THE WESTERN DESERTS CUTOFF FROM THE MONSOON FLOW.
PYTLAK
.TWC...NONE.
FXUS65 KFGZ 150430 az
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE JACKSONVILLE FL
150 AM EDT THU JUL 15 1999
RESENT...AN EARLY VERSION OF THE AFD WAS ACCIDENTLY RELEASED.
CURRENTLY...CONVECTION HAS SHIFTED TO OFFSHORE AND ALONG THE
IMMEDIATE COASTAL AREAS. THE MAIN CONVECTION IS FOUND OVER APALACHEE
BAY...WERE RUC AND WV IMAGERY INDICATE A VORT CENTER MOVING THROUGH
THAT REGION. GRAYS REEF WIND INSTRUMENT STILL NOT REPORTING BUT
GUSTS...10 METER WINDS AND SEAS ALL APPEAR TO BE IN LINE WITH
CURRENT CWF PRODUCT.
SYNOPTIC...UPPER LEVEL HIGH CENTERED OFF HAT WITH A RIDGE BUILDING
SW INTO COASTAL GEORGIA. AN UPPER TROUGH CONTINUES TO EXTEND FROM
THE GREAT LAKES SOUTH TO THE LOWER MS RIVER VALLEY WITH A VORT
CENTER ROTATING AROUND THE WESTERN EDGE OF THE RIDGE OVER THE NE
GULF OF MEXICO. SURFACE FRONTAL SYSTEM LIES FROM COASTAL SC SW
ACROSS SE GA TO NEAR TLH...BUT THE FRONTAL BOUNDARY HAS BECOME VERY
BROAD AND DIFFUSE. THE ETA MODEL MAINTAINS THE SURFACE BOUNDARY
ACROSS THE REGION THROUGH 48 HOURS WITH GRADUALLY DECREASING
MOISTURE. THIS MODEL SHIFTS THE MOISTURE AND PRECIP OVER S-CENTRAL
GA TODAY AND SW TO THE PANHANDLE TOMORROW. NGM INDICATES MORE
AVAILABLE DEEP LEVEL MOISTURE THIS MORNING BUT DRIES THE REGION OUT
A BIT THIS AFTERNOON AS THE MOISTURE SHIFTS NORTHWARD WITH THE
BUILDING MID-ATLANTIC RIDGE.
TODAY...ALL MODELS EXHIBIT A BUILDING SOUTHEASTERLY FLOW PATTERN
ACROSS THE REGION. THIS SHOULD BRING IN SOME LOW LEVEL ATLANTIC
MOISTURE AND ENHANCE THE EAST COAST SEA BREEZE. EXPECT THE
CONVECTION TO BREAK OUT IN INLAND AREAS...BUT THE LOW LEVEL FLOW
SHOULD SHIELD THE EAST COAST FROM SIGNIFICANT CONVECTION THIS
AFTERNOON. AVG 1ST PERIOD HI TEMP ERROR AT AMG THIS WEEK IS +4 SO
WILL GO WITH THE FLOW AND SHAVE 4 DEGREES OFF THE FWC HIGH TEMP.
TONIGHT...CONVECTION SHOULD END AROUND MIDNIGHT IN THE INTERIOR.
WITH THE SERLY FLOW CONTINUING THE COASTAL AREAS MAY SEE AN ISOLATED
SHOWER OVERNIGHT...SEE IT AS A SLIGHT CHANCE AND WILL GO 20 PCNT.
FRIDAY AND MARINE...THE SOUTHEASTERLY LOW LEVEL FLOW CONTINUES WITH
THE RIDGE AXIS ALONG 31-32 NORTH. CONVECTION SHOULD BE A REPEAT OF
TODAY WITH NEAR CLIMO POPS. COASTAL WINDS SHOULD BE EAST TO
SOUTHEAST AT 10-15 KNOTS OVER THE COASTAL WATERS THROUGH THE PERIOD.
WITH A LONG FETCH AREA...SEAS SHOULD BE GRADUALLY BUILDING...SUGGEST
KEEPING SEAS 2 TO 4 FEET THROUGH OUT THE ENTIRE PERIOD.
PRELIM
AMG 85/71/88/71 4132
SSI 88/74/85/75 3232
JAX 90/72/89/73 2222
GNV 91/69/92/68 4131 05
SANDRIK
FXUS62 KJAX 151014 COR fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
150 AM EDT THU JUL 15 1999
CURRENTLY...CONVECTION HAS SHIFTED TO OFFSHORE AND ALONG THE
IMMEDIATE COASTAL AREAS. THE MAIN CONVECTION IS FOUND OVER APALACHEE
BAY...WERE RUC AND WV IMAGERY INDICATE A VORT CENTER MOVING THROUGH
THAT REGION. GRAYS REEF WIND INSTRUMENT STILL NOT REPORTING BUT
GUSTS...10 METER WINDS AND SEAS ALL APPEAR TO BE IN LINE WITH
CURRENT CWF PRODUCT.
SYNOPTIC...UPPER LEVEL HIGH CENTERED OFF HAT WITH A RIDGE BUILDING
SW INTO COASTAL GEORGIA. AN UPPER TROUGH CONTINUES TO EXTEND FROM
THE GREAT LAKES SOUTH TO THE LOWER MS RIVER VALLEY WITH A VORT
CENTER ROTATING AROUND THE WESTERN EDGE OF THE RIDGE OVER THE NE
GULF OF MEXICO. SURFACE FRONTAL SYSTEM LIES FROM COASTAL SC SW
ACROSS SE GA TO NEAR TLH...BUT THE FRONTAL BOUNDARY HAS BECOME VERY
BROAD AND DIFFUSE. THE ETA MODEL MAINTAINS THE SURFACE BOUNDARY
ACROSS THE REGION THROUGH 48 HOURS WITH GRADUALLY DECREASING
MOISTURE. THIS MODEL SHIFTS THE MOISTURE AND PRECIP OVER S-CENTRAL
GA TODAY AND SW TO THE PANHANDLE TOMORROW. NGM INDICATES MORE
AVAILABLE DEEP LEVEL MOISTURE THIS MORNING BUT DRIES THE REGION OUT
A BIT THIS AFTERNOON AS THE MOISTURE SHIFTS NORTHWARD WITH THE
BUILDING MID-ATLANTIC RIDGE.
TODAY...ALL MODELS EXHIBIT A BUILDING SOUTHEASTERLY FLOW PATTERN
ACROSS THE REGION. THIS SHOULD BRING IN SOME LOW LEVEL ATLANTIC
MOISTURE AND ENHANCE THE EAST COAST SEA BREEZE. EXPECT THE
CONVECTION TO BREAK OUT IN INLAND AREAS...BUT THE LOW LEVEL FLOW
SHOULD SHIELD THE EAST COAST FROM SIGNIFICANT CONVECTION THIS
AFTERNOON. AVG 1ST PERIOD HI TEMP ERROR AT AMG THIS WEEK IS +4 SO
WILL GO WITH THE FLOW AND SHAVE 4 DEGREES OFF THE FWC HIGH TEMP.
TONIGHT...CONVECTION SHOULD END AROUND MIDNIGHT IN THE INTERIOR.
WITH THE SERLY FLOW CONTINUING THE COASTAL AREAS MAY SEE AN ISOLATED
SHOWER OVERNIGHT...SEE IT AS A SLIGHT CHANCE AND WILL GO 20 PCNT.
FRIDAY AND MARINE...THE SOUTHEASTERLY LOW LEVEL FLOW CONTINUES WITH
THE RIDGE AXIS ALONG 31-32 NORTH. CONVECTION SHOULD BE A REPEAT OF
TODAY WITH NEAR CLIMO POPS. COASTAL WINDS SHOULD BE EAST TO
SOUTHEAST AT 10-15 KNOTS OVER THE COASTAL WATERS THROUGH THE PERIOD.
WITH A LONG FETCH AREA...SEAS SHOULD BE GRADUALLY BUILDING...SUGGEST
KEEPING SEAS 2 TO 4 FEET THROUGH OUT THE ENTIRE PERIOD.
PRELIM
AMG 85/71/88/71 4132
SSI 88/74/85/75 3232
JAX 90/72/89/73 2222
GNV 91/69/92/68 4131 05
SANDRIK
FXUS62 KMLB 150123 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
225 AM EDT THU JUL 15 1999
05Z SFC ANALYSIS AND MSAS DATA SHOWS MOST OF THE AREA GENERALLY UNDER
HIGH PRESSURE RIDGING IN FROM THE ATLANTIC (BERMUDA HIGH)WITH JUST A
HINT OF A WEAK TROFF OVER E CNTRL KY. SAT PIXS AND RADAR COMPOSITES
SHOWING THAT ALL SHRAS AND MOST CLDS FROM EARLIER IN THE EVENING HAVE
DISSIPATED.
MAIN FCST PROBLEM TODAY (AND TOMORROW) WILL BE THE HANDLING OF WIDELY
SCATTERED OR SCATTERED AFTERNOON SHRA S/TSRA S. MODELS INDICATE WEAK
5H TROFF AXIS/VORT TO REMAIN OVER CNTRL-E KY TODAY...ALBEIT LESS THAN
YESTERDAY IT MAY BE ENUFF TO AID IN THE DEVELOPMENT OF A FEW TSRA S.
AIRMASS REMAINS FAIRLY MOIST FROM JUST ABOVE SFC TO NEAR 7H. FCST
SOUNDINGS SHOWING FAIRLY UNSTABLE CONDITIONS WITH MUCH LESS OF A
CAPPING INVERSION TODAY THAN YESTERDAY. LAPSE RATES FAIRLY STEEP IN THE
AFTERNOON...EVEN STEEPER TOMORROW AFTERNOON. FAIRLY HIGH THETA-E AIR
IN PLACE AGAIN TODAY AND SE ZONES ESPECIALLY LIE UNDER A THETA-E MAXIMA
THIS AFTERNOON. WEAK LL MOISTURE CONVERGENCE NOTED TOO.
WITH ALL THIS SAID WILL INTRODUCE LOW POPS/SLIGHT CHANCE OVER N-CNTRL
ZONES (20%) AND GO WITH A 30% OVER THE MORE MOUNTAINOUS TERRAIN AND
GENERAL AREA OF MOST UNSTABLE AIR. THINKING THAT OROGRAPHICS WILL ALSO
AID A TAD IN THE DEVELOPMENT OF SCT CONVECTION. THINKING MOST ACTIVITY
WILL BE THIS AFTERNOON AND WILL DIE OUT BY SUNSET. WILL GO WITH PS
TODAY...MC OR BECOMING MC TONIGHT. PATCHY FOG. WILL TAKE A LOOK AT THE
NEW (03Z) MESO-ETA RUN AND 06Z RUC BEFORE MAKING FINAL ZONE BREAKUP
DECISIONS.
WILL HOLD OFF ATTM ON THROWING POPS IN FOR FRIDAY AND WILL LET DAY
SHIFT TAKE A LOOK AT THE 12Z RUN. PS SKIES EXPECTED WITH TEMPS IN THE
UPPER 80S.
FOR THE EXTENDED PERIODS...HIGHER HEIGHTS/DIRTY 5H RIDGE HOLDS OVER THE
OHIO VALLEY. MRF TRIES TO WORK A FRONT SLOWLY SE THRU THE PERIOD AND
HINTS AT POSSIBLE FROPA MONDAY NIGHT OR SO. THINKING THAT THE AIRMASS
WILL REMAIN QUITE MOIST AND FAIRLY UNSTABLE THRU THE PERIOD. MODELS ALL
HINT AT WEAK VORTS TRAPPED UNDER THE RIDGE AND THINK THAT THERE WILL BE
WIDELY SCT...MAINLY AFTERNOON CONVECTION POSSIBLE EACH DAY. CURRENT
EXTENDED IS RUNNING DRY...WILL GO AHEAD AND CHANGE THIS TO MENTION CHC
OF AFTERNOON TSRA S.
MOS FAN TEMPS LOOK REAL CLOSE. MOS POPS KIND OF ON THE LOW SIDE.
WORK ZONES OUT SHORTLY. COMMENTS WELCOME.
THANKS TO SDF FOR COORDINATION.
.JKL...NONE.
HALL
FXUS63 KJKL 150127 ky
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
552 AM EDT THU JUL 15 1999
JUST ISSUED A QUICK UPDATE TO DROP POPS ACROSS EASTERN UPPER AND
HASTEN CLOUD LOSS. LATEST RUC SHOWS THETA-E RIDGE DROPPING SOUTH
ACROSS NORTHERN LOWER AND DIMINISHING AS SHORT WAVE AND LOW LEVEL
JET DEPART THIS MORNING. NORTHERN LOWER WILL BE UPDATED TO DROP POPS
IN THE NEXT COUPLE OF HOURS AS SUPPORT DIMINISHES.
.APX...NONE.
BAK
FXUS63 KMQT 150756 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
240 AM CDT THU JUL 15 1999
...TSRA CHANCES ARE THE MAIN CONCERN THRU THE PERIOD...
06Z SFC ANALYSIS SHOWS MANY DIFFERENT BOUNDARIES AACROSS THE AREA. THE
MAIN COLD FRONT...STEMING FROM THE LOW IN ERN MT EXTENDS ACROSS SRN
MT...WHILE A WELL DEFINED WARM FRONT LIES ACROSS NRN SD. FURTHER S...A
WEAK LOW OVER PHP SD HAS A WASHED OUT FRONT AXIS EXTENDING SWD FROM
IT...TO BETWEEN VTN AND SNY. WINDS EARLIER THIS EVENING WERE E/NERLY
BEHIND THIS OLD FRONT BUT HAVE SINCE RETURNED BACK TO THE SE AS
PRESSURES CONTINUE TO FALL. NICE RISE/FALL COUPLET IN ADAP PRESSURE
CHANGE DATA SUGGESTS THE ERN MT LOW WILL CONTINUE SEWD. KLNX 88D
SHOWING ONGOING CONVECTION MAINLY DRIVEN BY AN AREA OF ISENTROPIC LIFT
AS SHOWN BY THE 03Z RUC...AND IS PROGGED TO WEAKEN WITH TIME. TSRA HAVE
DEREASED IN INTENSITY AS THEY MOVED INTO MORE STABLE AIR. TSRA WAS
LIKELY ELEVATED IN NATURE INITIALLY AS INFERRED FROM THE 00Z 7/15/99
SOUNDING AND THE FACT THAT THERE WAS A GREAT DEAL OF LIGHTNING EARLY
ON.
THE NGM SFC PROGS ARE TOO FAST THRU 48 HRS WITH THE WEAK/OLD FRONT
ACROSS THE STATE ATTM GIVEN THE FACT THAT PRESSURES CONTINUE TO FALL
BEHIND THE FRONT. IN THE UPPER FEATURES...ALL MODELS ARE IN FAIR
AGREEMENT WITH SHEARING OUT THE CURRENT LONG WAVE TROF IN THE QUICK NRN
FLOW...THEN BRINGING THE NEXT ONE INTO THE NWRN PART OF OREGON BY 48
HRS. THIS SETS UP A SWRLY FLOW ALOFT WITH WEAK SHORT WAVES EMBEDDED IN
IT...WHICH SHOW UP BETTER AT 700 MB. SO WILL GO WITH A BLEND OF
ETA/AVN. MAIN COLD FRONT WILL WAIT UNTIL FRIDAY MORNING TO COME THRU
MOST OF THE CWA...AS LEE TROF/WASHED OUT FRONT TRIES TO PUSH EWD ACROSS
THE STATE TODAY. THIS FRONT WILL LIKELY NOT MOVE MUCH FROM WHERE IT IS
NOW THO...MAYBE A TAD FURTHER EWD. WEAKEST CONVECTIVE INHIBITION WILL BE
LOCATED FROM NC INTO C NEB BY 00Z FRI WITH CAPES RUNNING >3000 J/KG.
WITH 700 MB FLOW BEHIND THE FRONT FROM THE W...WOULD EXPECT CONVECTION
TO FORM A SQUALL LINE JUST AHEAD OF THIS TROF/OLD FRONT AS UPPER LEVEL
DIVERGENCE INCREASES AS WELL. MAIN FOCUS OF ACTIVITY THO WILL LIKELY BE
IN SD CLOSER TO THE BEST SOURCE OF MID/UPPER FORCING. WITH NUMEROUS
BOUNDARIES IN THE CWA THO...WILL INCLUDE POPS EVERYWHERE FOR THIS
AFTERNOON AND WAIT TILL ISSUANCE TIME TO WORRY ABOUT WORDING OF PRECIP
FOR THIS MORNING. LOTS OF MID AND HIGH LEVEL MOISTURE WHICH IS NOT
HANDLED WELL AT ALL IN THE NGM.
FOR FRIDAY...ETA HAS THE FRONT PUSHING PAST NRN KS BY 00Z SAT. NOT SURE
I AGREE WITH THIS GIVEN THE FACT THAT EARLIER IN THE WEEK ALL MODELS
HAD A FRONT THRU HERE BY NOW. SO WILL BRING THE FRONT THRU OUR
CWA...BUT HANGING UP IN NRN KS SOMEWHERE FRIDAY. WITH WEAK WAVES
EMBEDDED IN THE FLOW AND HARD TO SEE IN MODELS...WILL CONTINUE WORDING
OF LOW POPS AS IN CURRENT ZONES.
TEMPS WILL BE A CHALLENGE...BUT WITH MORE CLOUDS AROUND TODAY AND A
GRADUAL COOLING OF TEMPS ALOFT...WILL GO COOLER THAN WED MAXES IN THE SW
TODAY...NEAR THE SAME FURTHER W AND E. ON FRI...WITH COLD FRONT THRU THE
CWA...WILL STICK WITH GOING FORECAST WHICH IS IN LINE WITH GUIDANCE.
NO NEW GUIDANCE IN FOR THE EXTENDED SO AT THIS TIME WON'T CHANGE
ANYTHING. WILL WAIT UNTIL NEW MRF COMES IN TO SEE IF THERE ARE MANY
DIFFS.
.LBF...NONE.
JWS
FXUS63 KGID 150725 ne
MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
915 AM PDT WED JUL 14 1999
SYNOPSIS...A MOIST AND UNSTABLE AIRMASS WILL REMAIN OVER MOST OF THE
REGION TODAY. AN UPPER LEVEL DISTURBANCE OVER SOUTHERN NEVADA WILL
HELP TRIGGER SHOWERS AND THUNDERSTORMS THROUGH THIS EVENING. A DRIER
SOUTHWEST FLOW WILL MOVE INTO THE REGION THURSDAY...PUSHING MUCH OF
THE MOIST AIR OFF TO THE EAST WITH ONLY ISOLATED AFTERNOON
THUNDERSTORMS EXPECTED.
DISCUSSION...UPPER CIRCULATION SEEN NICELY ON VISIBLE SATELLITE
IMAGERY OVER SWRN LINCOLN COUNTY MOVING STEADILY EWD. 12Z RUC
DEPICTED THIS NICELY ON ITS 3HR FORECAST. THE RUC SHOWS THE MAIN
VORTICITY CENTER MOVING OFF INTO SWRN UT BY 00Z WITH ANOTHER WEAKER
CENTER DEVELOPING AND MOVING INTO EXTREME NRN CLARK COUNTY DURING THE
SAME TIME PERIOD. THE NEW RUC IS SLIGHTLY DIFFERENT AND SEEMS TO HAVE
A POOR INITIAL PANEL ON THE MAIN VORT CENTER. IT TAKES THE CENTER
FARTHER S INTO NCNTRL AZ BY 03Z WITH THE SECONDARY CENTER INTO
EXTREME NWRN MOHAVE COUNTY BY 03Z. THIS SEEMS TO BE ON ONLY FOCUS FOR
THIS AFTERNOON AND EVENING ALONG WITH GENERAL ISENTROPIC UPGLIDE
ACROSS THE ENTIRE AREA THIS AFTERNOON AND EVENING. BETTER SHEAR TODAY
AS NW FLOW TO 30KTS AT H5 DEVELOPS AND S TO SW FLOW AT SURFACE AND
850MBS AROUND 15KTS. STORMS SHOULD MOVE FAIRLY QUICKLY TODAY IN MOST
AREAS. FLASH FLOOD WATCH STILL OK FOR NWRN AZ AS MID LEVEL TROUGH
AXIS SHOULD BE RUNNING THROUGH THAT AREA THIS AFTERNOON BUT WILL HAVE
TO RELY ON TRAINING OR JUST VERY STRONG STORMS TO PRODUCE FLOODING.
FOR LAS VEGAS VALLEY...STORMS SHOULD FORM OVER THE SPRING MOUNTAINS
LATER THIS MORNING AND ROLL THROUGH THE CITY DURING THE AFTERNOON.
AFTERNOON CAPES BETWEEN 1000 AND 2000 J/KG AND LIFTED INDICES TO
MINUS 4 OR 5 SHOULD PROVIDE PLENTY OF INSTABILITY. EVEN THOUGH NO
FLASH FLOOD WATCH WILL BE ISSUED ATTM FOR THE VALLEY WILL HAVE TO
KEEP AN EYE ON STORM DEVELOPMENT AS FEW COULD BE QUITE STRONG BUT
WITH OVERALL EWD MOVEMENT OF 15 TO 20 MPH. NO UPDATES PLANNED AS OF
NOW. SKRBAC
.LAS...A FLASH FLOOD WATCH HAS BEEN ISSUED. PLEASE REFER TO THE
LATEST RNOFFALAS STATEMENT FOR DETAILS.
FXUS65 KREV 141603 nv
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
245 AM EDT THU JUL 15 1999
HINT OF OLD BOUNDARY CONTINUES TO BE EVIDENT ALONG THE COAST IN
MSAS SURFACE MOISTURE FLUX AND STREAMLINE FIELDS. HEALTHY AREA OF
CONVECTION W/ COOLING TOPS IS SLOWLY WORKING INTO HORRY/MARION
COUNTIES DRIVEN BY WEAK IMPULSE IN THE S/SWLY FLOW ALOFT. ONE HOUR
STANDARD Z/R ESTIMATED RAFL RATES GENERALLY RANGE FROM 0.75-1.50
INCHES IN THIS AREA. UPPER HIGH SEEN IN WATER VAPOR/RUC OFF THE SE
COAST IS KEEPING MOIST PLUME AXIS DIRECTED INTO THE CAROLINAS FROM
FL AND THE NE GULF OF MEXICO. SOUNDINGS FROM 00Z (MHX/CHS) REVEAL
PWS >2.00 INCHES AND LIFTED INDICES IN MARGINAL-MODERATE RANGES
FROM MHX-CHS RESPECTIVELY. CHANCE POPS WILL BE THE BEST WAY TO GO
TODAY...DON/T FEEL COMFORTABLE GOING HIGHER W/ NOTHING
SUBSTANTIALLY DEFINED IN THE FLOW ALOFT. ETA TIME-HEIGHT CROSS
SECTIONS POINT TOWARD DRYING ABOVE H8 THIS EVENING AND FRI AS WLY
FLOW DEEPENS. THIS SEEMS REASONABLE W/ UPPER HIGH OFF THE SE COAST
TO SLIP TOWARD NE FL AND E GA...ELUDING TO MORE SUN ON FRI AND
WARMING TREND. NGM GUIDANCE HAS FARED WELL ALONG THE COAST THE LAST
COUPLE OF DAYS...THOUGH WAY TOO WARM INLAND AREAS W/ COOL RIDGE
ANCHORED THERE. WILL CONTINUE TO UNDERCUT NGM TEMPS IN THE INLAND
ZONES AND STICK CLOSER COASTAL AREAS.
CWF: TOTALLY AGREE W/ MHX THAT MODELS HAVE BEEN EXTREMELY WEAK THIS
EVENT. IT HAS BEEN A FRUSTRATING SET OF MIDS. AT ANY RATE...W/
BOUNDARY LINGERING ACROSS THE WATERS WILL INITIALIZE W/ VARIABLE
WINDS TODAY...THEN TREND TOWARD SWLY FLOW. 3 FT SWELLS CONTINUE.
PRELIMINARY CCF:
ILM EB 084/071 087/071 089 29423
FLO EE 079/070 085/070 088 29323
MYR EB 082/072 083/071 084 29433
.ILM...NONE.
PFAFF
FXUS72 KRAH 150644 nc
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
905 PM CDT WED JUL 14 1999
NO UPDATE PLANNED. WEAK HIGH PRESSURE OVR NRN RRV IS SLOWLY DRIFTING
EAST ALG THE NRN MN BORDER...WELL HANDELED BY 12Z MODEL SUITE. NRLY
FLOW INTO FGF CWA HAS STABILIZED LOW LEVELS FOR THE EVENING. LATE
TONIGHT AND TOWARDS MORNING...STILL EXPECT TSTM DEVELOPMENT INTO
AREA. LOW LVL MOISTURE ADVECTION HAS INTENSIFIED LAST FEW HOURS INTO
CNTRL SD WITH A TIGHT INSTABILITY GRADIENT FROM HON NWD TO THE ND
BDR. 00Z RUC PUSHES MOISTURE CONVERGENCE ZONE INO SCNTRL ND BY 06Z
AND INTO NRN RRV BY 12Z...WITH ACCOMPANYING WARM FRONTAL SURGE.
CURRENT TEMPS AND PCPN TIMING ARE GOOD.
.FGF...NONE.
GUST
FXUS63 KBIS 142038 nd
TEXAS/OKLAHOMA PANHANDLES AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE AMARILLO TX
1037 PM CDT WED JUL 14 1999
SFC TROUGH REMAINING STATIONARY IN ERN NM WITH SSE WINDS ACROSS THE
PNHDLS. LATEST RUC/NGM/ETA FCSTG TROUGH TO GRADUALLY SHIFT EAST INTO
WRN PART OF PNHDL BY DAYBREAK. THEREFORE...WILL UPDATE ZONES TO BACK
WINDS AROUND TO S IN THE WEST AND S TO SE IN CNTRL AND ERN ZONES.
.AMA...
TX...NONE.
OK...NONE.
JH
FXUS64 KCRP 150236 AMD tx
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
218 AM MST THU JUL 15 1999
SYNOPSIS...HIGH PRESSURE DEVELOPING SOUTH OF ARIZONA WILL SLOWLY
FEED DRIER AIR INTO THE REGION. HOWEVER...ANOTHER ROUND OF SCATTERED
THUNDERSTORMS CAN BE EXPECTED THIS AFTERNOON AND EVENING. WITH
PLENTY OF MOISTURE STILL AROUND...A FEW STORMS COULD ONCE AGAIN
PRODUCE HEAVY DOWNPOURS. THE HIGH PRESSURE AREA WILL GRADUALLY
MIGRATE INTO THE SOUTHERN PLAINS OVER THE WEEKEND. WHILE THIS STILL
FAVORS MONSOON THUNDERSTORMS...THE ACTIVITY WILL NOT BE AS
WIDESPREAD AS IT HAS BEEN RECENTLY.
DISCUSSION...WESTERLY FLOW HAS COMMENCED, BUT WE'RE NOT OUT OF THE
WOODS YET (OR TROPICAL RAIN FOREST AS THE CASE MAY BE). A SLEEPER
SHORT WAVE IN THE KLAS AREA, WHICH IS FUELING A SMALL, SLOW-MOVING
MCS NEAK KIGM, WAS ONLY PICKED UP WELL BY THE ETA AND RUC. THEY TAKE
IT ACROSS NORTHERN AZ TODAY WITH A TRAILING, WEAK LOBE THROUGH SE AZ
JUST AFTER 00Z. BASED ON CURRENT MOVEMENT, THAT MAY NOT BE TOO BAD.
FLOW AND SHEAR PROFILES AREN'T AS STRONG AS YESTERDAY, SO THE DEGREE
OF RELOADING IS IN DOUBT. HOWEVER, DEEP TROPICAL MOISTURE REMAINS
(PRECIP WATERS IN THE 1.5-1.75" RANGE) WITH SOME MID LEVEL COOLING
EXPECTED. THERE WILL ALSO BE SOME UPPER DIVERGENCE BETWEEN THE VORT
AND THE 300MB HIGH TO OUR SOUTH. THIS MAY EXPLAIN THE ONGOING
CONVECTION ALONG OUR SOUTHERN BORDER AND ISOLATED ELEVATED SHOWERS
AS FAR NORTH AS PINAL COUNTY. THE SLOW DRYING MAY BE JUST ENOUGH TO
KEEP OUR FLASH FLOOD THREAT DOWN, BUT DAY SHIFT WILL HAVE TO WATCH
AND MAY NEED TO BEEF UP WORDING ONCE WE GET THE 12Z UPPER AIR DATA.
THE TORRENTIAL RAIN OVER THE NORTH AND EAST CWA LAST NIGHT HAS
REALLY SATURATED THINGS WITH MANY WASHES STILL RUNNING THIS MORNING.
TO SUM UP, PREVIOUS FORECAST IS IN GOOD SHAPE OTHER THAN A DOWNWARD
TWEAK ON HIGHS TODAY AND SLIGHT POP INCREASES FROM TUCSON EAST THIS
AFTERNOON/EVENING. TOMORROW DEFINITELY LOOKS LIKE A DOWNER WITH
LOWER THETA-E AND SOME WARMING ALOFT. WEAK FLOW SHOULD KEEP MUCH OF
THE ACTIVITY NEAR THE MOUNTAINS WITH A SLIGHT WARMUP DUE TO LESS
CLOUD COVER. NO MRF AVAILABLE AS YET, BUT OTHER MEDIUM RANGE MODELS
MAINTAIN A TROUGH JUST OFF THE WEST COAST. THAT SUPPORTS OUR CURRENT
EXTENDED WITH ONLY THE WESTERN DESERTS CUTOFF FROM THE MONSOON FLOW.
PYTLAK
.TWC...NONE.
FXUS65 KFGZ 150430 az
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
1025 AM EDT THU JUL 15 1999
SFC ANALYSIS SHOWS LOW LEVEL TROUGH EXTENDING FROM THE NE GULF OF
MEXICO ACROSS SE GA. RADAR HAS SHOWN WIDELY SCATTERED SHOWER AND
THUNDERSTORM ACTIVITY IN THE COASTAL WATERS SINCE EARLY THIS
MORNING. SUGGEST REMOVING MENTION OF AFTERNOON IN COASTAL WATERS.
RUC AND MESO-ETA INDICATE LOW LEVEL CONVERGENCE CONCENTRATED OVER NE
FL AND BECOMING STRONGER BY LATE AFTERNOON WHICH SEEMS REASONABLE.
ZONES HAVE GOOD CHANCE POPS INLAND TODAY AND CHANCE COASTAL AREAS.
GENERALLY AGREE WITH THIS GIVEN MORNING SOUNDING WHICH SHOWED LOWER
PW AND LITTLE MORE STABLE ATMOS COMPARED TO YESTERDAY. MODIFIED LI
-6 AND CAPE NEAR 2500 J/KG. ONLY PROBLEM WILL BE HOW MUCH UPPER
LEVEL DIVERGENCE WILL BE AVAILABLE TO AID TSTMS. NGM SEEMED TO BE
THE STRONGEST WITH REGARD TO THIS COMPARED TO AVN AND ETA. ST.
AUGUSTINE CMAN SHOWS 6-8 KT SE FLOW ASSOCIATED WITH A SEA BREEZE.
FOR NOW...WILL NOT CHANGE FORECAST.
ARS
FXUS62 KTBW 151412 fl
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
955 AM EDT THU JUL 15 1999
RECENT SURFACE OBSERVATIONS INDICATE SEA BREEZE STARTING TO SET UP
EARLY ALONG THE COAST. RADAR SHOWS WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS MOVING NORTHWEST OVER THE COASTAL WATERS WITH SOME
COMING ONSHORE. SHOWER AND THUNDERSTORM ACTIVITY APPEARS TO HAVE
FORMED UNDER THE LEFT FRONT QUADRANT OF A WEAK EASTERLY JET
APPROACHING THE FLORIDA PENINSULA FROM THE ATLANTIC. SUSPECT THE
ACTIVITY WILL DIMINISH AS THE MID LEVEL SUBSISTENCE ASSOCIATED ALONG
THE PERIPHERY OF A TUTT CELL EAST OF THE BAHAMAS CONTINUES TO MOVE
TOWARD FLORIDA. THIS SHOULD REDUCE CHANCES OF PRECIPITATION THIS
AFTERNOON FOR THE COAST FROM BREVARD COUNTY SOUTHWARD. AGREE WITH MIA
ABOUT THE LOW AND MID LEVEL EASTERLIES STRENGTHENING. THE RUC
GUIDANCE WITH VISIBLE SATELLITE IMAGERY OVERLAID ALSO SUPPORTS THE
EASTERLIES STRENGTHENING
FOR THE MORNING UPDATE...WILL KEEP A 30 PERCENT OF RAIN FOR THE
INLAND COUNTIES AND REMOVE MENTION OF MORNING SHOWERS FROM BREVARD
SOUTH. TEMPERATURES LOOK OK.
MARINE...BUOY 10 INDICATING CONSISTENT 10 KNOT SOUTHEAST WIND AND
WILL NOT MAKE ANY CHANGES TO THE GOING COASTAL WATERS FORECAST.
.MLB...NONE
WIMMER/TROUTMAN
FXUS72 KMFL 151333 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1030 AM CDT THU JUL 15 1999
ONLY QUESTION ON UPDATE IS TIMING OF CONVECTION IN CENTRAL PORTIONS
OF FORECAST AREA. TREND OF LATEST RUC MODEL IS TO COOL LOW LEVELS
SOME THIS AFTERNOON...BUT PROBABLY NOT ENOUGH TO BREAK CAP IN
CENTRAL...HAVE REDUCED CHANCE OF SHOWERS IN CENTRAL AREA. BEST
GRADIENT ALONG WITH ISALLOBARIC GRADIENT IS TO NORTHWEST OF
AREA...HAVE REDUCED WINDS IN WISCONSIN ZONES. TEMPERATURES STILL
LOOK GOOD FOR AFTERNOON...BUT WITH RELATIVELY SHORT DURATION WILL
NOT ISSUE HEAT ADVISORY.
.MSP...NONE
SCOTT
FXUS63 KMPX 150851 mn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
900 AM MDT THU JUL 15 1999
...ZONES WILL BE UPDATED...
COLD FRONT WHICH CROSSED THE CWA EARLIER THIS MORNING HAS MOVED INTO THE
DAKOTAS. SATELLITE IMAGERY INDICATING CLEARING TREND TAKING PLACE FROM
WEST TO EAST ACROSS THE CWA THIS MORNING AS DRIER AIR PUSHES IN ON
WESTERLY FLOW. UPPER LOW IN NWRN MONTANA PROGGED TO MOVE EASTWARD ALONG
THE US/CANADIAN BORDER TODAY/TONIGHT. SLIGHT COOLING ALOFT ASSOCIATED
WITH THIS FEATURE INDICATED BY 12Z RUC. THIS MIGHT MAKE ATMOS UNSTABLE
ENOUGH FOR ISOLATED AFTN/EVNG SHOWERS AND THUNDERSTORMS TODAY. HOWEVER
WITH LOW LEVEL DRYING TAKING PLACE THANKS TO INCREASING NORTHWEST WINDS
BEHIND THE FRONT...WILL LOWER POPS TO ISOLATED ACROSS THE CWA TODAY AND
FOR SERN MONTANA THIS EVNG. WILL ALSO RAISE FIRST PERIOD TEMPS A TAD IN
SHERIDAN SINCE THEY ARE ALREADY IN THE UPPER 60S AND SHOULD HAVE PLENTY
OF SUNSHINE TODAY. DS
BIL BB 080/049 080/053 084 62222
LVM .. 075/046 075/... ... 62222
HDN .. 081/048 081/... ... 62222
MLS .. 082/053 080/050 ... 62222
4BQ .. 084/055 082/... ... 62222
BHK .. 081/048 080/... ... 62222
SHR BB 085/048 081/050 083 62222
FXUS65 KMSO 150954 mt
MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
910 AM PDT THU JUL 15 1999
SYNOPSIS...LINGERING MOISTURE AND A HIGH LEVEL DISTURBANCE
APPROACHING THE AREA FROM CENTRAL CALIFORNIA WILL PROVIDE FUEL FOR
SOME AFTERNOON AND EVENING THUNDERSTORMS AGAIN TODAY. INCREASING
SOUTHWEST FLOW WILL BEGIN TO PUSH THE MOISTURE EAST OF THE REGION ON
FRIDAY LEADING INTO A DRY PATTERN FOR THE WEEKEND.
DISCUSSION...SATELLITE WATER VAPOR IDENTIFIES HIGH LEVEL SHEAR
VORTICITY OVER CENTRAL CALIFORNIA STARTING TO CROSS THE SOUTH-CENTRAL
SIERRA OVER MONO AND NORTHERN INYO COUNTIES. RUC AND MESO-ETA MODELS
AGREE PUSHING HIGH LEVEL VORTICITY AROUND 200-300 MB TO THE E-NE INTO
SOUTH CENTRAL NEVADA THIS AFTERNOON AND EARLY EVENING...WHILE MID
LEVEL VORTICITY AROUND 400-500 MB ROUNDS SOUTHERN CALIFORNIA
ANTICYCLONE INTO EXTREME SOUTHERN NEVADA BY EARLY THIS EVENING. MID
LEVEL UNSTABLE LOOKING CLOUDS ARE ALREADY EDGING THROUGH SOUTHERN NYE
COUNTY TOWARDS SOUTHERN LINCOLN AND WESTERN CLARK COUNTIES PRETTY
MUCH IN BETWEEN ABOVE TWO TRAJECTORIES. MESO-ETA AND RUC ALSO
IDENTIFY BEST LOW LEVEL STREAMLINE CONVERGENCE OVER SOUTH CENTRAL
NEVADA TODAY. THIS DISTURBANCE WILL NOT COME INTO AREA AS WELL
DEFINED AS LAST NIGHTS NOW EDGING ACROSS SOUTHERN ARIZONA...BUT FEEL
SHOULD BE ENOUGH LIFTING TO RAISE POPS ACROSS MUCH OF SOUTH CENTRAL
NEVADA TO SCATTERED LEVELS.
WATER VAPOR SATELLITE ALSO IDENDTIFIES SIGNIFICANT MID LEVEL DRYING
HAS OCCURED FOR THE ENTIRE AREA WITH PRECIPITABLE WATERS DOWN NEARLY
1/2 INCH. SOUTHWEST FLOW ALOFT WILL TRANSLATE INTO SOME INCREASE IN
THE SURFACE SOUTH TO SOUTHWEST FLOW BY MID TO LATE AFTERNOON...MAINLY
SOUTH CENTRAL NEVADA AND INYO COUNTY...BUT ACCORDING TO RUC/MESO-ETA
NOT AS STRONG AS IN GOING FORECAST. AND ALSO NOT ENOUGH WESTERLY
COMPONENT TO BRING NOTABLE SURFACE DRYING VERY MUCH INTO OUR AREA YET
TODAY. WILL LEAVE FORECAST PRETTY MUCH ALONE FOR AREAS TO THE SOUTH
OF SOUTH CENTRAL NEVADA WITH SLIGHTLY BETTER MOISTURE STILL LYING
EAST OF THE COLORADO RIVER VALLEY SUPPORTING SCATTERED COVERAGE
VERSUS ISOLATED TO THE WEST. DECENT WESTERLY CELL MOVEMENT TODAY AND
GENERALLY LOWER CAPES IN ADDITION TO LOWER PRECIPITABLE WATERS
MENTIONED ABOVE SHOULD PRECLUDE SIGNIFICANT TROUBLE EITHER FROM HIGH
WIND THREAT OR FLASH FLOODING.
AFTERNOON FORECAST WILL LOOK MORE CLOSELY AT DEGREE OF DRYING
SPREADING IN FROM THE WEST AND HOW LONG BEFORE MONSOON RETURNS.
MCQUEEN
.LAS...NONE.
FXUS65 KLKN 151549 nv
WESTERN NEVADA AND EASTERN CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
845 AM PDT THU JUL 15 1999
DRIER AIRMASS HAS WORKED ITS WAY INTO WESTERN NEVADA WITH DEW POINTS
DOWN AS MUCH AS AROUND 30 DEGREES IN NORTHWEST NEVADA. ALSO COOLER
ACROSS THE AREA WITH TEMPS DOWN AROUND 5 DEGREES AND AROUND 3-4
DEGREES THROUGH 600 MB ON THE MORNING SOUNDING. MAIN THREAT TODAY FOR
THUNDERSTORMS APPEARS TO BE ACROSS OUR SOUTHERN PORTION OF THE CWA.
SURFACE FRONT FROM AROUND A SALT LAKE TO AUSTIN TO BRIDGEPORT LINE AND
WATER VAPOR IMAGE SHOWS A WEAK VORT MAX HEADING INTO SOUTHERN SIERRA.
RUC BRINGS PORTION OF VORT MAX ACROSS AREA THIS AFTERNOON AND WITH
RESIDUAL MOISTURE AND SOME LOW LEVEL FOCUS WITH FRONT SHOULD KEEP SOME
CHANCE OF CONVECTION TODAY. CURRENT FORECAST COVERS THIS SO NO UPDATES
NECESSARY. PIKE
.REV...EASTERN CALIFORNIA...NONE.
WESTERN NEVADA...NONE.
FXUS65 KVEF 151106 nv
MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
405 AM PDT WED JUL 14 1999
SYNOPSIS...LINGERING MOISTURE WILL PROVIDE FUEL FOR SOME AFTERNOON
AND EVENING THUNDERSTORMS ACROSS SOUTHERN NEVADA AND NORTHWEST
ARIZONA TODAY. AN INCREASING SOUTHWEST FLOW WILL BEGIN TO PUSH THE
MOISTURE EAST OF THE REGION ON FRIDAY LEADING INTO A DRY PATTERN FOR
THE WEEKEND.
DISCUSSION...THUNDERSTORM COMPLEX OVER MOHAVE COUNTY EARLIER THIS
MORNING HAS MOVED EAST OF THE FORECAST AREA WITH NEW STORMS FIRING
OVER ADJACENT COUNTIES TO THE SOUTH AND EAST. LINGERING LOW AND MID
LEVEL MOISTURE OVER MUCH OF THE FORECAST AREA IS EVIDENT FROM SURFACE
OBSERVATIONS AND THE LATEST IR SATELLITE IMAGERY. THE MAIN SYNOPTIC
FEATURES TO NOTE ARE THE UPPER LOW CENTERED NEAR NORTHERN IDAHO AND
ALSO A WEAKER MID LEVEL CIRCULATION GENERATING VERTICAL MOTION OFF
THE CENTRAL CALIFORNIA COAST. OTHER MODELS DID NOT INITIALIZE THE
LATTER WELL BUT ACCORDING TO THE 09Z RUC...THIS FEATURE SHOULD REMAIN
ALONG THE COAST FOR AT LEAST THE NEXT 12 HOURS.
THE 00Z DRA SOUNDING SHOWS SIGNIFICANTLY LESS PRECIPITABLE WATER THAN
PREVIOUS RUNS...1.03 INCHES VERSUS ABOUT 1.4 INCHES...BUT ENOUGH FOR
SOME THUNDERSTORMS TODAY. DOES NOT APPEAR THAT LINGERING MOISTURE
WILL BE QUICK TO LEAVE SO MENTION OF ISOLATED STORMS TODAY FOR MOST
ZONES IS WARRANTED WITH MOHAVE COUNTY A LITTLE MORE FAVORABLE FOR
SCATTERED THUNDERSTORMS. DRYING TREND WILL BECOME MORE EVIDENT FRIDAY
AS SOUTHWEST FLOW PERSISTS ACROSS THE AREA. FRONTAL BOUNDARY DROPPING
INTO CENTRAL NEVADA LATER TODAY AND TONIGHT MAY FOCUS SOME CONVECTION
OVER NYE AND LINCOLN COUNTIES INTO THE NIGHT SO ADDED MENTION TO
RESPECTIVE ZONES.
DID NOT MAKE CHANGES TO THE EXTENDED PERIOD AS LATEST MEDIUM RANGE
MODELS SHOW DRY PATTERN THROUGH SUNDAY AND A POSSIBILITY OF MOISTURE
WORKING ITS WAY UP FROM THE SOUTH ON MONDAY FOR A CHANCE OF
THUNDERSTORMS. JGA
.LAS...NONE.
FXUS65 KREV 150945 nv
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BINGHAMTON NY
945 PM EDT THU JUL 15 1999
EVERYTHING IN THE MORNING FORECAST LOOKS GOOD...SO WILL NOT MAKE ANY
CHANGES. PARTLY SUNNY WILL WORK OUT WELL FOR THIS AFTERNOON.
CONVECTIVE TEMPS BUF/84 ALY/82 SO CU WILL BE DVLPG THIS AFTERNOON. RUC
DETAILS A LITTLE VORT MAX MOVG THROUGH W. NY NOW AND IS REFLECTED IN SAT
VIEW/OBS WITH SOME 12000 FT AC. RUC ALSO SHOWS A LITTLE PVA ASSOC WITH
TROF AND CLOUD REMNANTS OF THIS MORNING'S MCS IN UPPER MICH...EXPECT
MAINLY MID LEVEL CLOUDS LATE AFTN/EARLY EVENING WITH THIS PASSING
THROUGH OUR FORECAST AREA.
WORK ZONES WILL BE SENT SHORTLY FOR COORDINATION.
.BGM...NONE.
CHIARAMONTE
FXUS61 KOKX 151322 ny
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
1022 AM CDT THU JUL 15 1999
OUTFLOW BOUNDARY FROM EARLIER CONVECTION EXTENDING FROM EXTREME NW MN
INTO EAST CENTRAL ND THIS AM AND WILL PROVIDE A FOCUSING MECHANISM FOR
THUNDERSTORM DEVELOPMENT LATER TODAY. THE SEVERE STORMS HAVE LIFTED NE
OUT OF EXTREME NW MN...BUT MORE CONVECTIVE ACTIVITY DEVELOPING OVER
CENTRAL AND EASTERN ND ATTM. THIS ACTIVITY ASSOCIATED WITH SFC LOW OVER
SW ND/NW SD AND AHEAD OF VORT LOBE PUSHING THROUGH ND THIS AM. LATEST
SATELLITE DATA SHOWS CLOUD TOPS COOLING THIS AREA ALONG WITH INCREASING
LIGHTNING STRIKES. 12Z RUC INDICATES THAT LIS OVER FA TO CONTINUE TO
FALL...REACHING TO AS LOW AS -11 OVER FAR ERN ZONES BY 18Z WHERE MORE
SUN IS EXPECTED. WITH RADAR...SFC AND SATELLITE TRENDS SUPPORTING
INCREASING CONVECTIVE ACTIVITY...AND WITH THIS ACTIVITY FORECAST TO
PUSH INTO NW MN THIS AFTERNOON...WILL UP POPS ALL AREAS...ESPECIALLY NE
ND. CLOUD COVER AND PRECIPITATION WILL HOLD HIGHS TEMPS DOWN OVER
PORTIONS OF ERN ND AND NW MN AND WILL CUT HIGHS THESE AREAS
ACCORDINGLY. SE ZONE TEMP TRENDS ON TRACK AS READINGS THERE ALREADY IN
THE LOWER 80S.
WILL SEND UPDATED ZFP SHORTLY.
TURNER
FXUS63 KFGF 150818 nd
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
1100 AM CDT THU JUL 15 1999
WINDS ARE MAIN CONCERN THIS AFTERNOON. THIS MORNINGS PROFILERS 850MB
WINDS HAVE COME DOWN FROM OVERNIGHT...BUT 12Z RUC SHOWS A CONTINUED
INCREASE IN THE PRESSURE GRADIENT THROUGHOUT THE AFTN. GOING
FORECAST LOOKS GOOD FOR NOW BUT WILL CONT TO MONITOR JUST IN CASE WE
NEED TO BUMP SOME OF THESE AREAS UP LATER TODAY. OTHERWISE FORECAST
HAS THINGS IN HAND. NO UPDATES ANTICIPATED AT THIS TIME BUT WILL
CONT TO MONITOR.
30
.OUN...
OK...CAUTION ON AREA LAKES WEST THIS AFTERNOON.
TX...CAUTION ON AREA LAKES PORTIONS OF WESTERN NORTH TEXAS THIS
AFTERNOON.
FXUS64 KOUN 150906 ok
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1015 AM EDT THU JUL 15 1999
CURRENT GSP VAD WINDS DISPLAY NE DIRECTION WHICH IS BASICALLY ALONG
TERRAIN RATHER THAN UPSLOPE. THIS DIRECTION SIMILAR TO LOW-LEVEL
OBJECTIVELY ANALYZED WINDS FOR ENTIRE CWA THIS MRNG. THUS...VIRTUALLY
NO UPSLOPE FLOW ATTM. 03Z ETA AND 09Z RUC FCST LGT LOW-LEVEL WINDS TO
BCM SE LATER TDA. THUS...WK UPSLOPE WILL DVLP AND CREATE
CORRESPONDINGLY WK FORCING FOR AFTN CNVCTN. TRADITIONAL STABILITY
INDICES ON THE LOW SIDE AND ILL-DEFINED E/W TROF EVIDENT AT 850/700 MB
NR NRN BORDER OF CWA SHOULD NOT BE MAJOR PLAYER SO DO NOT EXCEPT SIG
SHWR/TSTM DVLPMNT. CURRENT TEMP FCSTS SEEM TO BE GOOD...BUT WILL HAVE
TO LOOK AT SAT PIX TO CHECK ON CLOUD TRENDS BFR FINALIZING AFTN MAXES.
LGL
FXUS62 KCAE 151358 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
932 AM EDT THU JUL 15 1999
LATEST VIS SAT AND OBS SUGGEST BREAKS WILL CONT IN THE EARLY MORNING
CLOUDS. RUC FCST SOUNDING OVR CWA ALSO IS INITIALLY SATURATED BUT SHOWS
DRYING BY AFTN. THIS MEANS NO WEDGE OVR AREA AS WINDS BECOME LIGHT SE BY
AFTN. WITH DECREASING CLDS WILL BUMP MAX TEMPS UP SLIGHTLY. RUC SHOWS
SHORT WAVE THRU THIS AFTN OVR THE CWA AND LI'S IN THE -2 TO -4 RANGE.
WITH THE INCREASE IN SUN...MDT INSTABILITY...AND BREAKDOWN OF WEDGE
BELIEVE THAT WDLY SCT SHWRS/TSTMS ARE POSSIBLE AND WILL KEEP CURRENT
POPS RANGING FROM 30 TO 50 PCT. HIGHEST POP OF 50 PCT IS IN SRN PTN OF
CWA IN KEEPING WITH LATEST RUC PCPN FCST.
.CAE...NONE.
BLP
FXUS62 KCHS 151352 sc
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
940 AM CDT THU JUL 15 1999
DRY AIRMASS ACROSS MOST OF FA TODAY. PW SLIGHTLY HIGHER ACROSS
EASTERN ZONES AND THIS IS WHERE RUC IS DEVELOPING PRECIP
THIS AFT. A FEW SHOWERS OCCURRING JUST EAST OF FA AND OFFSHORE
THIS MORNING. WILL RE-ALIGN ZONES TO INCLUDE SLIGHT CHANCE ACROSS
UPPER COAST AND EXT EAST...ELSEWHERE EXPECT A LOT OF SUN AND
LOW-MID 90 HIGH TEMPS.
NO CHANGES NECESSARY TO MARINE ZONES.
.HGX...NONE.
33/40
UPDATED PRELIMS...
CLL BB 094/073 094/073 093 002
IAH BB 094/073 094/074 092 --3
GLS BB 089/080 089/081 089 223
FXUS64 KBRO 151437 tx
SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
950 AM MST THU JUL 15 1999
.SYNOPSIS...
THE WEATHER DISTURBANCE THAT PRODUCED HEAVY RAIN AND THUNDERSTORMS IN
SOUTH-CENTRAL ARIZONA THIS MORNING WILL CONTINUE MOVING TO THE EAST.
NEVERTHELESS...ENOUGH MOISTURE REMAINS FOR A CHANCE OF THUNDERSTORMS
IN SOUTH-CENTRAL ARIZONA THIS AFTERNOON AND EARLY THIS EVENING...WITH
A SLIGHT CHANCE OF SHOWERS OR THUNDERSTORMS LINGERING OVER THE HIGHER
TERRAIN FRIDAY. THE AIR CONTINUES TO BE QUITE MOIST OVER SOUTHEASTERN
CALIFORNIA AND SOUTHWESTERN ARIZONA...BUT SOME DRIER AIR IS EXPECTED
TO MOVE IN FROM THE SOUTHWEST LATER TODAY AND FRIDAY TO DECREASE THE
POSSIBILITY OF SHOWERS AND THUNDERSTORMS.
.DISCUSSION...
SHORT-WAVE TROUGH AND ASSOCIATED VORT MAX MOVED OVER S-CNTRL AZ THIS
MORNING AND PRODUCED HEAVY RAIN AND SOME THUNDERSTORMS. THIS SYSTEM
APPEARS TO HAVE MOVED EWD AND IS NOW PRODUCING LOCALLY HEAVY RAIN
JUST SE OF THE PHX CWA. THE ETA INITIALIZED THE TROUGH AND VORT MAX
FAIRLY WELL THIS MORNING...BUT MAY NOT HAVE BEEN STRONG ENOUGH WITH
IT CONSIDERING THE AMOUNT OF WEATHER IT PRODUCED. DATA HAS BEEN VERY
SLOW TO COME IN THIS MORNING...WITH ONLY 12 HOURS OF THE ETA AND NO
NGM. THE RUC DID NOT DO WELL ON INITIALIZING THE SYSTEM OVER S-CNTRL
AZ THIS MORNING AND HAS BEEN DISCOUNTED. THE 00Z MODEL SERIES...WITH
THE ETA CONSIDERED BEST...SHOWED ANOTHER VORT MAX DROPPING IN OVER
THE S-CNTRL AZ AREA LATER TODAY/TONIGHT FOR POSSIBLY ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS. THE CURRENT FORECAST IS PREDICATED ON THAT
IDEA...SO WILL LEAVE THAT AS IS...BUT WILL UPDATE FOR CURRENT TRENDS
AND ASSOCIATED CHANGES IN THE FIRST PERIOD. WILT
FXUS65 KPSR 151645 az
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
255 PM EDT THU JUL 15 1999
SHORT TERM...GUIDANCE INDICATES THAT THE EASTERLY FLOW WILL REMAIN
DEEP AND MOIST ENOUGH OVERNIGHT TO LEAVE COASTAL SHOWERS IN AFTER
MIDNIGHT AGAIN FROM THE CAPE SOUTH. RUC AND MESOETA MID LEVEL MEAN
RELATIVE HUMIDITY PROGS AND CURRENT WATER VAPOR SATELLITE IMAGERY
LOOPS SHOW DRIER AIR WILL CONTINUE WORK ITS WAY OVER THE STATE
TONIGHT WHICH SHOULD HOLD THE THREAT OF ANY COASTAL WATERS STORM
ACTIVITY TONIGHT.
FOR TONIGHT...SLIGHT CHANCE OF COASTAL SHOWERS...ESPECIALLY AFTER
MIDNIGHT. A CHANCE OF EVENING STORMS THEN CLEARING FOR THE INLAND
COUNTIES. TEMPERATURE GUIDANCE LOOKS OK.
LONG TERM...MODELS ARE IN SIMILAR AGREEMENT IN MOVING THE UPPER
LEVEL TUTT LOW TO THE SOUTH OF THE FA BY SATURDAY INTO SUNDAY. A
DECENT EASTERLY FLOW WILL CONTINUE FROM AT LEAST THE CAPE SOUTHWARD
THRU THE FORECAST PERIODS WITH THE MAIN EMPHASIS BEING REDUCED
PRECIP CHANCES ESPECIALLY FOR THE COASTAL PORTIONS OF THE FA. ANY
PRECIP WOULD BE MAINLY IN THE AM TO AROUND NOON HOURS ALONG THE
COAST. MODEL FORECAST SOUNDINGS FROM THE ETA/AVN/NGM ALL SHOW THAT
PWAT VALUES ARE PROGGED TO DROP BELOW CLIMO BY FRIDAY AND STAY JUST
NEAR CLIMO THRU THE REST OF THE FORECAST. ONLY A MENTION OF SLIGHT
POPS ARE WARRANTED FOR THE MOST OF THE FA FOR FRIDAY WITH THE
SUBSIDENCE EXPECTED TO CONTINUE MOVING WEST INTO THE FA.
ALL MODELS PROG THE TUTT LOW TO CONTINUE TO MOVE TO THE SOUTH AND
SOUTHWEST OF THE FA INTO THE EXTENDED FORECAST. DECENT LOW LEVEL
MOISTURE WILL BEGIN ADVECTING NORTHWEST AROUND THE PERIPHERY OF THE
TUTT LOW BY 12Z SATURDAY AND WILL NEED TO UP POPS INTO THE CHANCE
CATEGORY FOR THE FA FOR SATURDAY. TEMPS ARE CLOSE WITH BOTH MODELS
AND BASICALLY ACCEPTED.
.MARINE...BUOY 10...LAPS AND MSAS MESOSCALE DATA CONTINUES TO
INDICATE SOUTHEAST WINDS AROUND 10 KNOTS ACROSS THE COASTAL WATERS
AND WILL BASICALLY CONTINUE THIS TREND INTO FRIDAY NIGHT.
PRELIMINARY NUMBERS...
DAB BB 073/088 073/089 074 11121
MCO BB 073/092 074/091 074 11221
MLB BB 075/089 076/089 076 11121
.MLB...NONE
WIMMER/TROUTMAN
FXUS62 KTAE 151854 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY-RUSKIN, FL
230 PM EDT THU JUL 15 1999
NGM/ETA/RUC MODEL ANALYSIS CONTINUED TREND OF LOWER PRECIPITABLE
WATER LEVELS ACROSS THE CENTRAL FLORIDA PENINSULA TO 1.5 INCHES
THROUGH THE NEXT 24 TO 48 HOURS. NGM IS THE MOST FERVANT WITH THIS
TREND WHILE THE ETA DOWNPLAYS IT. FOR THE NEXT 48 HOURS...ALL
MODELS CONTINUE TBW FORECAST AREA IN E-SE DEEP FLOW WITH LATE
OFFSHORE AM AND LATE AFTERNOON/EVENING CONVECTION.
SUGGEST MOSTLY SUNNY DAYS...BECOMING PARTLY CLOUDY WITH GOOD CHANCE
OF LATE DAY SHOWER AND THUNDERSTORM ACTIVITY OVER WEST FLORIDA COAST
NEXT TWO DAYS. NGM MOS TEMPS ACCEPTED. FAN PRECIP VALUES BETTER.
ZALESKI
FXUS62 KEYW 151758 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
952 AM EDT THU JUL 15 1999
NO UPDATES NEEDED THIS MORNING. MODELS SHOWING A WEAK VORTICITY MAX
PASSING ACROSS OUR CWA THIS AFTERNOON. 09Z RUC INDICATING SOME LOW
LEVEL MOISTURE AND FAIRLY DECENT INSTABILITY AND LIFT ALONG THE
MOUNTAINS. BUT NO SURFACE TRIGGER AVAILABLE FOR WIDESPREAD
CONVECTION. BEST CHANCE SHOULD BE ALONG THE MOUNTAINS WITH SOME
ISOLATED THUNDERSTORMS POSSIBLE IN THE VALLEY. SURFACE OBS AND
SATELLITE SHOWING CLOUDS BEGINNING TO SCATTER OVER MOST OF THE CWA...
ALLOWING FOG TO BURN OFF QUICKLY. FEW CLOUDS MOVING UP FROM THE SOUTH
AND SOME CU PROBABLY FORMING THIS AFTERNOON...BUT TEMPERATURES STILL
LOOK ON TRACK.
GH
FXUS74 KMEG 150903 tn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
310 PM EDT THU JUL 15 1999
AWIPS PROBLEMS HAS LEAD ME BACK TO AFOS THIS AFTERNOON. SAT IMAGE
INDICATED PLENTY OF SUNSHINE ACROSS CWA WITH MOST OF THE CU IN THE
MOUNTAINS. REFERRAL TO THE KFCX 88D...SHOWED THAT A FEW SHOWERS HAD
DEVELOPED IN THE SW MOUNTAINS. WEAK EASTERLY WIND COMPONENT HAS
RESULTED IN SOME LIFT. SATELLITE MOISTURE LOOP HAD DRIER AIR ACROSS
MOST OF THE FA TODAY...BUT DID DISPLAY SOME MOISTURE CREEPING NORTH
ACROSS NC. THIS MORNING NASA SE MM5 KEEP CWA DRY THRU 12 HOURS. IN
CONTRAST...THE 15Z RUC PRINTOUT SOME RAIN MAINLY ALONG THE WESTERN
MOUNTAINS. IN ANY CASE...EXPT SHOWERS TODAY TO DSPT QUICKLY SIMILIAR
TO YESTERDAY. LOOKING AT A 500MB COMPARISION OF THE MODELS THIS
MORNING...APPEARS TAHT THE RIDGE BUILD EASTWARD DURING THE PERIOD.
THERE IS ABIT OF DIFFERENT ON HOW THEY HANDLE THE VORT MAXS (PLACED
THIS MORNING ON THE UPPER AIR ANALYSIS TO OUR WEST) ROTATING
EASTWARD. AFTER VIEWING SEVERAL PRODUCTS LIKE LIS...THETAE...RH
FEILDS...CAPES... ETC... MY IMPRESSION IS THAT THERE IS A CHC OF AN
EVENING SHOWER IN THE WEST TONIGHT OTHERWISE PC WITH PATCHY FOG.
FRIDAY WILL BE PARTLY SUNNY AND VERY WARM (MAY RISE HIGHS CLOSER TO
MOS GUIDANCE) WITH CHC OF AN AFTERNOON SHOWER OR THUNDERSTORM MAINLY
IN THE WEST. SUMMER RETURNS. HAVE A GUD EVENING.
.RNK...
VA...NONE.
NC...NONE.
WV...NONE.
KK
FXUS71 KRLX 151450 va
EASTERN WASHINGTON AND NORTH IDAHO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WASHINGTON
920 AM PDT THU JUL 15 1999
WATER VAPOR LOOP SHOWS EAST WA AND NORTH IDAHO BETWEEN SYSTEMS. FIRST
SYSTEM IS THE ONE CURRENTLY OVER NW MT...RAPIDLY MOVING EASTWARD.
RESIDUAL MOISTURE FROM THIS SYSTEM REMAINS TRAPPED OVER NORTHEAST
WASHINGTON AND THE IDAHO PANHANDLE AND SHOULD BE HARD PRESSED TO MOVE
OUT AS WEAK RIDGE BUILDS INTO AREA. EXPECT THESE AREAS WILL REMAIN
MOSTLY CLOUDY TODAY...HOWEVER LOOK AT 12Z OTX SOUNDING AND FORECAST
SOUNDING FROM THE RUC INDICATE LITTLE THREAT OF PRECIPITATION GIVEN A
DEVELOPING CAP BETWEEN 600-700MBS. SOUNDINGS ALSO INDICATE A BIT OF
WARMING IN THE LOWER LEVELS...GIVEN WEAK E-NE FLOW DEVELOPING OVER
THE REGION IN RESPONSE TO OTHER SYSTEM DROPPING OFF THE BC COAST.
TEMPS IN THE BALL PARK SO WONT TOUCH THEM. AS FOR BC SYSTEM...WATER
VAPOR SHOWING SYSTEM CONTINUING TO DIG TO THE SW OVER THE OCEAN AND
FARTHER AWAY FROM THE AREA. DYNAMICS FROM THIS SYSTEM SHOULD LEAVE
MOST OF OUR CWA UNSCATHED TODAY. THE LONE EXCEPTION WILL BE THE
NORTHERN PORTION OF THE EAST SLOPE ZONES WHERE MID-LEVEL COOLING AND
UPSLOPE FLOW COULD BE JUST ENOUGH TO TRIGGER SOME SHOWERS AND
THUNDERSTORMS LATER THIS AFTERNOON.
...THE INFORMATION IN THIS PRODUCT CONCERNING WARNINGS AND FORECASTS
IS VALID ONLY AT THE TIME OF ISSUANCE. THE LATEST WARNING AND
FORECAST INFORMATION WILL BE FOUND IN THE APPROPRIATE PRODUCTS...
GEG 069/050/074 013
CQV 071/049/075 113
S86 068/048/071 123
COE 069/051/073 013
WWP 066/047/070 113
LWS 076/054/080 002
MOS 067/049/072
EAT 075/054/077 023
.GEG...NONE.
FXUS66 KSEW 151551 wa