AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1020 PM EDT SUN MAY 7 2000
...FCST CONCERNS INVOLVE CONVECTION AND SVR WX THREAT LATE TONIGHT...
RADAR/SATELLITE SHOW BLOSSOMING CONVECTION IN THE PLAINS STATES HAS
A BROAD UL TROUGH BEGINS TO MOVE EAST OVER THE HOT AND HUMID WEATHER
THAT HAS BUILT UP OVER THE PLAINS. IN THE U.P. THE FRONT THAT COOLED
TEMPERATURES QUITE A BIT HERE IN MQT HAS STALLED ALONG THE SOUTHERN
COUNTIES. SCT SHRA AND TSRA CONTINUE IN THE AREA OF BEST SFC
CONVERGENCE AND ELEVATED INSTABILITY.
LOW PRESSURE IS DEVELOPING AT THE SFC OVER SW SOUTH DAKOTA AT 02Z.
THE AREA OF BEST PRESSURE FALLS IS OVER CENTRAL MN WHICH LEADS ME TO
BELIEVE THAT THIS FIRST LOW WILL MOVE NE TO A POSITION OVER KDLH BY
MID MORNING TOMORROW. THE EFFECT OF THIS WILL BE TO LIFT THE FRONT
NORTH TONIGHT AND BRING THE U.P. INTO THE WARM SECTOR. FIRST WE WILL
HAVE TO CONTEND WITH CONVECTION BREAKING OUT OVER THIS BOUNDARY AS
THE INCREASING LLJ PUSHES THE FRONT NORTH. ALL OF THE CONVECTION WILL BE
ELEVATED WITH SHOWALTER INDICES ON THE 00Z RUC OF -2 TO -4C FOR MOST
OF THE NIGHT...SO WHEN THE TRIGGER ARRIVES (THE FRONT) THERE WILL BE
AMPLE OPPORTUNITY FOR CONVECTION. CAPES RANGE FROM 500 NR THE LK
SUPERIOR SHORELINE TO ALMOST 2K NR MNM. MOST OF THE UL DYNAMICS
APPEAR TO BE HEADING TOWARD THE WEST...AND WILL HIT THE WORDING
HARDER OUT THERE. WITH THE STG WAA...LOWS WILL ONLY BE A FEW DEGREES
OFF OF PRESENT LEVELS. WILL UPDATE MANY FOR TIMING OF CONVECTION.
.MQT...NONE.
ALTOE
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FXUS63 KDTX 080139 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
915 PM EDT SUN MAY 7 2000
WATER VAPOR IMAGERY AT 00Z INDICATED THAT UPPER LEVEL VORTICITY MAX
WAS LOCATED NEAR BMG IN INDIANA. THIS WAS CLOSE TO THE RUC AND MESO
ETA MODELS.
KILN RADAR SHOWS SHOWERS...MOST CONCENTRATED ALONG AND SOUTH OF THE
OHIO RIVER. AS OF LATE...CLOUD TO GROUND LIGHTNING WAS NOT
OCCURRING. LOSS OF SOLAR INSOLATION HAS DECREASED THE AMOUNT OF
SBCAPE ACROSS THE REGION. THUS...ANY THUNDERSTORM ACTIVITY THAT MAY
DEVELOP WILL BE DUE TO THE PROXIMITY OF THE VORT MAX...AND THIS
SHOULD BE ISOLATED. VORT MAX IS FORECAST TO MOVE VERY SLOWLY SOUTH
OF THE OHIO RIVER OVERNIGHT. PCPN SHOULD DECREASE ONCE THE CENTER
OF ROTATION PASSES BY. WILL SHOW A DECREASING TREND WEST AND WILL
KEEP THE HIGHEST POPS SOUTH OF THE OHIO RIVER. THE POSSIBILITY OF
AN MCS OVERNIGHT DOES NOT LOOK LIKELY. THE VORT MAX OVER ST LOUIS
THIS AM SEEMED TO HAVE MUCH MORE UPPER DIVERGENCE THAN WHAT IS
FORECAST OVERNIGHT. ALSO...I AM NOT IMPRESSED WITH A 20 TO 30 KT
LOW LEVEL JET. THUS...I WILL REMOVE MENTION OF HEAVY RAIN.
TEMPERATURES LOOK RIGHT ON TRACK FOR TONIGHT.
.ILN...NONE.
HICKMAN
FXUS61 KCLE 071850 oh
CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1020 AM EDT SUN MAY 7 2000
...WORK ZONES OUT AS PHLADMCTP...
VIS IMAGERY SHOWING NEARLY CLOUDLESS SKIES ACROSS CENTRAL PA THIS AM
WITH TEMPS IN GENERAL A BIT WARMER THAN THIS TIME YESTERDAY. EXPECT
HIGHS TO ONCE AGAIN REACH NEAR 90 IN THE SUSQ VALL WITH M-U80S MOST
OTHER SPOTS. REC HIGH OF 93 AT MDT IS NOT COMPLETELY OUT OF THE
QUESTION BUT WILL LEAVE OUT OF ZONES FOR NOW. CU MACRO CONTINUES TO
SUGGEST PTSUNNY SKIES OVER THE N AND W MTNS WHILE AREAS TO THE EAST
REMAIN MSUNNY.
RUC SOUNDINGS ALSO CONTINUE TO SUGGEST WIDELY SCT CONVECTION
POSSIBLE. WILL KEEP 20 POPS GOING THROUGH EARLY EVENING.
.CTP...NONE.
FITZGERALD
pa
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
1015 AM CDT SUN MAY 7 2000
MCS ACROSS EASTERN MO/SOUTHERN IL SLOWLY SHRINKING. LATEST RUC/ETA
SUGGESTS MAIN AFFECT OF DYING SYSTEM SHOULD REMAIN TO THE NORTH OF
THE CWA. LOW-LEVEL RIDGING WILL WEAKEN SOME TODAY BUT STILL HELP
KEEP PRECIP SCATTERED AT BEST. FEW WEAK BOUNDARIES SETTING UP ACROSS
AREA FROM MCS AND EXPECT DEVELOPMENT THIS AFTERNOON WITH DEWPOINTS
RISING INTO THE MID 60S AND SURFACE/BOUNDARY LAYER INSTABILITY
INCREASING. WILL UP POPS TO SCATTERED CATEGORY. TEMPS NEED LITTLE
WORK AS WELL. 07
BNA...NONE.
FXUS64 KMRX 071408 tn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
510 PM CDT SUN MAY 7 2000
A FEW HIGH-BASED THUNDERSTORMS HAVE FORMED IN THE EXTREMELY HIGH
LAPSE RATE AIR WEST OF THE DRY LINE. STILL NOT SURE THAT LOWER-
BASED (BUT STILL RELATIVELY HIGH-BASED GIVEN THE TEMP AND
DEW POINTS AT SPS) CONVECTION CAN FORM ON THE DRY LINE...GIVEN THE
STRENGTH OF THE CAP. HOWEVER...AWIPS LAPS AND RUC2 DATA INDICATE
THAT CAPPING INVERSION HAS WEAKENED IN THE AREA BETWEEN SPS AND
ABI AS TEMPS HAVE WARMED ABOVE 100 DEG F AGAIN.. SO A FEW
THUNDERSTORMS THAT ACTUALLY COULD BE INGESTING SOME GULF MOISTURE ARE
POSSIBLE.
WE WILL UPDATE AND CALL FOR ISOLATED THUNDERSTORMS WITH GUSTY WINDS
IN THE NORTHWESTERN ZONES.
.FTW...CAUTION ON AREA LAKES CENTRAL AND WEST TONIGHT.
26
FXUS64 KEPZ 072019 tx
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
600 PM CDT SUN MAY 7 2000
SCT TSTMS CURRENTLY ACTIVE NORTH OF STATIONARY FRONTAL BOUNDARY IN
AXES OF MOISTURE CONVERGENCE/INSTABILITY OVER NC/NE WI. HAVEN'T SEEN
ANYTHING APPROACHING SVR CRITERIA YET...BUT WE'RE WATCHING AN AREA
IN WSTRN ONEIDA AND NORTHERN LINCOLN COUNTIES...WHERE VSBL SATL IMAGERY
SHOWS AN APPARENT BOUNDARY INTERACTION OCCURRING. NEW DEVELOPMENT
JUST STARTING UP THERE ATTM.
WITH RESPECT TO LATER TONIGHT...CURRENT THOUGHTS ARE THAT MOST OF THE
TSTM ACTIVITY WILL REAMIN OVER NORTHERN WI...CLOSE TO SFC/H8 BOUNDARIES.
BEST H8 MOISTURE CONVG LINGERS THERE OVERNIGHT AS DEVELOPING LLJ RIDES
OVER THE LLVL BOUNDARIES. WILL WATCH TRENDS CLOSELY OVER THE NEXT
FEW HOURS TO SEE IF PRECIP CHCS NEED TO BE ADJUSTED THIS EVG. RUC MODEL
SEEMS TO HAVE A GOOD HANDLE ON S/W TROF NR YELLOWSTONE NATL PARK AND
OFFERS A REASONABLE SOLN WRT TO LLVL BOUNDARIES AND MOISTURE CONVG
TRENDS OVERNIGHT. WITH THE EXCEPTION OF QPF...WHICH THE RUC IS NOT DOING
TOO WELL ON...WILL RELY ON RUC MODEL FOR SHORT-TERM TRENDS.
.GRB...NONE.
KIECKBUSCH
WWW.CRH.NOAA.GOV/GRB
FXUS63 KGRB 072035 wi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WICHITA KS
335 AM CDT MON MAY 8 2000
MAJOR CONCERN FOR THIS FORECAST IS SEVERE WEATHER AND FLOODING
THREAT LATE TODAY/TONIGHT/EARLY TUESDAY. UPPER AIR ANALYSIS AND
WATER VAPOR SAT PIX SHOW IMPRESSIVE UPPER JET PUNCHING INTO WESTERN
US. AT 07Z SFC COLD FRONT INTO NW KS...WITH PRE-FRONTAL TROF/OUTFLOW
BOUNDARY JUST WEST OF RSL. LIKED AN AVN/ETA MIX FOR THIS FORECAST AS
THEY VERIFIED BEST AT 06Z WITH POSITION OF SFC BOUNDARY AND POSITION
OF SFC LOW.
SFC FRONT FORECAST TO STALL OUT ACROSS SOUTH CENTRAL KS THIS
AFTERNOON. AHEAD OF THIS FRONT...CAPES FORECAST TO BE IN EXCESS OF
2750 J/KG PER ETA FORECAST SOUNDINGS...WITH WEAKENING CAP. WILL
INCREASE POPS ACRS CENTRAL/SC KS TODAY. CERTAINLY A POTENTIAL FOR
SVR WEATHER...BUT BEST SHEAR/LL CONVERGENCE FORECAST TO BE ALONG
KS/OK BORDER SOUTHWARD...SO FEEL BEST TORNADIC THREAT WILL BE JUST
SOUTH OF ICT...BUT LARGE HAIL POSSIBLE ACRSS MUCH OF SC KS.
WILL GO A LITTLE ABOVE GUIDANCE TEMPS AHEAD OF FRONT...BUT
LATEST RUC DATA SHOWS FRONT SWEEPING THROUGH FASTER THAN EARLIER
FORECAST...SO TEMPS MAY ONLY RISE A FEW DEGREES BEHIND BOUNDARY.
MAIN SHOW APPEARS TO BE TONIGHT AS INCREASING UPPER DIVERGENCE HELPS
DEVELOP A NEW SFC LOW IN THE OK PANHANDLE. 85H WRM FRONT FORMING
ACRS SRN KS AND 50+ KT 85H LOW LEVEL JET INTERSECTING THIS BOUNDARY
WILL SIGNIFICANTLY INCREASE LIFT IN SC/SE ZONES. MID LEVEL
COOLING/MID LEVEL DRY PUNCH HELPING TO STEEPEN LAPSE RATES SO
DAMAGING WINDS AND HAIL A STRONG POSSIBILITY IN SRN ZONES OVERNIGHT.
ALSO...WITH GOOD THETA-E ADVECTION NORTH OF THE BOUNDARY...AND
HIGH PW VALUES WILL HAVE TO MONITOR FLOODING POTENTIAL FROM WICHITA
TO WINFIELD AND POINTS EAST. NEEDLESS TO SAY...WILL HAVE HIGHEST POPS
IN SC/SE ZONES WITH SMALLER POPS IN NRN ZONES. SPS/HAZARDOUS WX
OUTLOOK WILL BE ISSUED AT 6 AM CDT TO DETAIL THESE THREATS.
EXPECT TSRA TO CONTINUE AHEAD OF 5H SHEAR AXIS EARLY TUESDAY...BUT
AS UPPER SYSTEM DEPARTS...GOOD SUBSIDENCE SHOULD SHUT OFF PCPN FROM
WEST TO EAST THROUGH THE DAY AND CLOUDS WILL DECREASE. DESPITE COOLER
85H TEMPS...WILL USE A FWC/FAN MIX FOR HIGHS TUESDAY.
SFC RIDGE OVER THE REGION TUESDAY NIGHT SUGGESTS COOLER FWC NUMBERS
FOR LOWS ARE THE WAY TO GO. SOUTHERLY LL FLOW BRINGING WAA SHOULD
BRING WARMER TEMPS WED.
LITTLE CHANGES MADE TO THE EXTENDED.
THANKS TO OUN/TUL/SGF/TOP.
FCSTID = 12/HYSELL
ICT 82 61 72 48 / 30 80 60 5
HUT 80 61 72 46 / 30 80 60 5
EWK 81 61 72 48 / 30 80 60 5
EQA 82 61 72 49 / 40 80 50 5
WLD 84 61 72 49 / 40 80 50 5
RSL 71 56 72 49 / 40 60 30 0
GBD 72 56 72 49 / 40 60 30 0
SLN 78 59 70 47 / 40 60 30 0
MPR 79 59 70 47 / 40 60 30 0
CFV 86 63 71 47 / 20 70 60 0
CNU 86 63 71 46 / 20 70 60 0
K88 85 63 71 46 / 20 70 60 0
.ICT...NONE.
FXUS63 KGLD 080825 ks
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
250 PM CDT MON MAY 8 2000
FCST CONCERNS: TIMING OF CONVECTION...TEMPS THRU PD...DURATION
OF PRECIP ON TUESDAY
CONVECTION ACRS SE AND SC NE RIDING ALNG THE EDGE OF 13-14C CAP
IN PLACE OVR CTL PLAINS. SOME DEVELOPMENT INTO NC KS BUT...LOOKS
FAIRLY WEAK. XPCT DYING CONVECTION TO REACH NW CORNER OF CWA BTWN
10Z AND 12Z.
NEXT QUESTION IS WHEN CAP WILL BREAK DURING THE DAY? ETA SHOWING
CAP ERODING ACRS NWRN THIRD OF CWA BY 18Z WHEREAS KEEPS A LID
ON THINGS UNTIL 21Z-24Z TIMEFRAME. WL USE AFTN WORDING TO COVR
DEVELOPMENT WHICH WL COVR EITHER SCENARIO. ETA/NGM/AVN LOOK
SIMILAR WITH PSN OF FRONT AT 18Z...RUC IS A LTL FASTER. ALL MODELS
HAVE FNT ALNG A IRK TO JUST SOUTH OF MKC LINE BY 00Z TUES. OF
COURSE...OUTFLOW FROM CURRENT CONVECTION MAY BE THE BNDRY TO WATCH
FOR DEVELOPMENT AND TIMING OF ACTION LATER TDA. ALL MODELS
SHOVE LO LVL THETAE RDG INTO SRN AND ERN SECTIONS OF CWA BY 06Z.
THUS...XPCT A BRIEF BREAK IN CONVECTION OVR NW HALF OF CWA DURING
THE EVENING THEN AS H8 LOW APPROACHES...CONVECTION WL BE DRAWN
NWD AGAIN. DONT QUITE KNOW HOW TO WORD THIS SCENARIO... WL
KEEP HIGH CHANCE OR LIKELY POPS IN FCST THRU TUESDAY AFTN ACRS
NW HALF AND ALL DAY TUESDAY TO THE EAST. WL HANG ONTO CHC POPS
ACRS ERN CWA THRU TUESDAY NIGHT.
TEMPS WL BE TRICKY TDA. CLD COVR AND FASTER MVMNT OF BNDRY WL
POTL HTG DOWN. WL SEE WHERE AND WHAT CONVECTION ACRS SE NE IS
DOING JUST BEFORE PKG IS RELEASED. GUID MINS TONIGHT LOOK A LTL
COOL GIVEN PROG DWPTS RMN AOA 60 FRM SOUTH OF A MCI TO IRK LINE
THUS...WL GO A CPL CATS ABV. CLDS...EVAP COOLING AND RAIN WL
MAKE FOR A COOL DAY ON TUESDAY. DONT HAVE ANY PROBLEMS WITH
GUID VALUES.
DIFFERENCES IN LONG TERM MODELS WITH REGARD TO THE DEVELOPMENT OF
LONGWAVE TROUGH PSN. MRF DEVELOPS AMPLIFIED TROF OVR WRN US
BY 12Z FRI WHEREAS...EUROPEAN MODELS AND CANADIAN ARE LESS
AMPLFIED AND KEEP TROUGH FAIRLY FLAT. WL TAKE A QUICK PEAK
AT ENSEMBLES BEFORE MAKING ANY CHANGES TO EXTENDED.
.EAX...NONE.
24
FXUS63 KSGF 080744 mo
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
330 AM CDT SUN MAY 7 2000
FCST CHALLENGE...WINDS TDY...DRY SLOT.
NEAR TERM...AS PER DISCUSSIONS WITH ABR WILL ISSUE WIND ADVISORY FOR
EXTREME ERN ND AND PORTIONS OF NW MN TDY. 06Z RUC AND ETA ARE
HANDLING TRACK OF SFC LOW THROUGH SRN AND CNTRL MN THE BEST THIS AM.
RUC. MSAS IS SHOWING MARKED REALIGNMENT OF SFC LOW PLACEMENT AS
PRESSURE FALLS TARGET THE BRD-DLH CORRIDOR. RUC IS SUPERIOR IN
HANDLING H8 WIND FIELD...AS CONFIRMED BY KBIS AND KMVX VWPS LAST
COUPLE HOURS. ETA SFC LOW TRACK INDICATES TIGHTER SFC PRES GRAD
THROUGH THE RRV WHILE STRONGER H8 WINDS...AND GOOD VERTICAL
COUPLING...SHOULD BRING MUCH OF THE RRV AND RRV "BEACH" AREA INTO
WIND ADVOSORY CRITERIA. LIGHT RAIN IN DEF ZONE FM NCNTRL SD INTO
NWRN MN...WITH DRY SLOT INDICATED TRHOUGH WCNTRL MN. WILL INDICATE
HIGH SCT THROUGH CATEGORIC POPS FOR MUCH OF AREA...AS DEF ZONE
SLOWLY TRACKS EWD. DRYING FM WEST SHOULD SHUT DOWN SHOWER ACTIVITY
IN DVL AREA BEFORE NOON.
MID TERM...FLAT H5 HEIGHT FIELD TNGT THROUGH TUESDAY SUGGESTS SOME
MID LVL MOISTURE BUT LITTLE ENERGY THROUGH THE PERIOD. SFC HIGH
PRESSURE TRACKS ACROSS THE DKTAS AND INTO THE RRV BY LATE TUESDAY SO
FAIRLY DRY AND STABLE LOW LVL NRLY FLOW EXPECTED. CLOUDS SHOULD
DIMINISH FM WEST TNGT WITH SOME COLD AIR STRATOCU LIKELY TUESDAY DAY
BUT GENLY FAIR WX. FWC TEMPS LOOK REASONABLE.
EXTENDED...00Z AVN SHOWING SFC LOW AND APPROACHING SHORTWAVE TO
AFFECT FA FOR WEDNESDAY. 30-40 KT H850 LLJ WILL BE ADVECTING
MOISTURE NORTHWARD INTO WESTERN FA BY 12Z WED...THEN INTO EASTERN
ZONES BY DAYS END. THIS COUPLED WITH STRONG UPPER LEVEL WINDS...LI/S
OF -2 AND SFC DEWPOINTS PROGGED INTO THE MID 50S WITH OPEN GULF
SPELL CHANCE FOR -TSRA WED. WILL NOT TINKER WITH REST OF EXTENDED AS
NEW MRF HAS NOT ARRIVED. QUICK GLANCE AT CANADIAN SHOWS UNSETTLED
WEATHER FOR REST OF WEEK...WITH THURSDAY THE DRIEST DAY AND THIS IS
HANDLED IN CURRENT FORECAST.
.FGF...WIND ADVISORY TODAY EXTREME ERN ND AND PORTIONS OF NW MN.
GUST/KELLENBENZ
FXUS63 KBIS 080830 nd
AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST
SOUTH DAKOTA AND WEST CENTRAL MINNESOTA
NATIONAL WEATHER SERVICE ABERDEEN SD
340 AM CDT MON MAY 8 2000
CHALLENGES TODAY INCLUDE POPS THIS MORNING AND THEN WINDS. 88D
MOSAIC ALONG WITH LIGHTNING PLOT SHOWS ALL THUNDERSTORM ACTIVITY HAS
EXITED TO EAST...BUT SHOWERS REMAIN OVER NORTH CENTRAL PORTION OF
CWA AND MORE WIDELY SCT SHOWERS NORTHWESTERN CWA. SHOWERS ASSOCIATED
WITH WRAP AROUND FROM SFC LOW NOW OVER SOUTHERN HALF OF MN AND 5H
VORT MAX MOVING EAST-NORTHEAST THIS MORNING. AS SFC LOW AND VORT MAX
CONTINUE TO MOVE EAST...AND DRIER AIR MOVES IN FROM WEST...AS SHOWN
IN GENERAL MODEL TRENDS INCLUDING ETA AND RUC...SHOWERS SHOULD PULL
OUT OR DISSIPATE THIS MORNING. WILL INCLUDE MENTION OF THIS TO
VARYING DEGREES IN TODAY'S FCST. WILL ALSO INCLUDE A 30 POP IN
SOUTHWESTERN COUNTIES BASED ON LINE OF SHOWERS NOW MOVING IN FROM
THE WEST. CHALLENGE THEN SHIFTS TO WINDS. RUC 925 WINDS 35-40 KTS
EASTERN 1/2 OF CWA...ALONG WITH A 12 MB PRESSURE DIFFERENCE ACROSS
CWA BY 15Z. WITH MODERATE CAA AND WEAK SUBSIDENCE...FEEL WINDS WILL
MIX DOWN TO SFC BY AFTERNOON. HOWEVER...CLOUDINESS COULD INHIBIT
MIXING SOMEWHAT AND MAY BE THE SPOILER. COORD WITH FGF...INDICATED
VAD WINDS AT BIS WERE ALREADY STRONGER THAN RUC INDICATED...SO WILL
GO WITH A WIND ADVISORY EAST FOR TODAY. REMAINDER OF PERIOD...WEAK
HIGH PRESSURE AND DRIER AIR TAKE OVER...ALONG WITH A DEVELOPING
SPLIT FLOW IN UPPER LEVELS...WITH STRONGER ENERGY TRANSITING TO
SOUTH ACROSS CO-KS 24 THROUGH 48 HOURS. GUIDANCE TEMPS IN FAIR
AGREEMENT AT LEAST FIRST AND SECOND PERIODS...AND HAVE FOLLOWED A
COMPROMISE OF FAN AND FWC.
.ABR...WIND ADVISORY TODAY EASTERN HALF CWA...BROWN AND SPINK
COUNTIES EASTWARD
LORENS
FXUS63 KFSD 080824 sd
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
240 AM CDT MON MAY 8 2000
FORECAST QUANDARIES...CLOUD COVER FIRST PERIOD...TEMPERATURES.
CURRENT AWOS/ASOS OBSERVATIONS...REGIONAL SATELLITE IMAGERY...
AND LAPS/SURFACE HAND ANALYSES SHOWING CWA UNDER SURFACE RIDGING
INFLUENCES CENTERED IN THE NORTHERN MOUNTAINS OF WV. SOUTHERLY WIND
FIELDS CONTINUE SUPPORTING "MUGGY" CONDITIONS...WITH BOTH
TEMPERATURES AND DEWPOINTS RANGING IN THE 60S. UPPER AIR RUC/CHART
ANALYSES DEPICTING UPPER LEVEL TROUGHING AND ASSOCIATED VORT MAX
MOVING EASTWARD OUT OF CWA...USHERING IN RIDGING INFLUENCES. OF A
PARTICULAR NOTE...A SEWD MOVING LOW LEVEL STRATUS DECK ENTERING W
PORTIONS OF REGION.
00Z MON REGIONAL MODEL INITIALIZATIONS GENERALLY SIMILAR WITH
THE NGM SOLUTION BEST INITIALIZED SURFACE AND ALOFT. ONLY
MINOR DIFFERENCES IN EVOLUTION OF WEATHER PATTERN THROUGH 00Z
THU WITH ALL MODELS INDICATING NO RELIEF FROM THE "MUGGY"
CONDITIONS EXPERIENCED LATELY. LOOK FOR LOWER LEVEL FLOW TO REMAIN
SLY/SWLY IN NATURE DURING PERIOD AS HIGH PLAINS LOW "COUPLES"
WITH NORTHERN MIDWEST LOW...ELONGATES SEWD INTO THE TX PANHANDLE...
WITH THE ENTIRE LOW PRESSURE SYSTEM MOVING INTO THE CENTRAL IL
BY 00Z WED. UPPER LEVEL RIDGING WILL BECOME ENHANCED THROUGH
THE PERIOD AS A TROUGH DEEPENS ACROSS THE CENTRAL U.S.
IN AGREEMENT WITH MODEL RH PROGS THAT UPPER LEVEL RIDGING
STRENGTHENING TODAY WILL NOT INHIBIT DEVELOPMENT OF VARIABLE
CLOUDINESS IN AREA AIRMASS. LOOK FOR STRENGTHENING IN OVERALL
SUBSIDENCE AFTER 00Z TUE...WITH SKY CONDITION WORDING FROM PREVIOUS
ZONE ISSUANCE "STILL IN LINE." BELIEVE THAT PCPN CHANCES AS
ILLUSTRATED IN 00Z MON FAN GUIDANCE ARE TOO HIGH...WITH CONVECTIVE
DEVELOPMENT ISOLATED AT BEST. WILL LEAVE FORECAST DRY THROUGH PERIOD.
TEMPS...WARM AIR ADVECTION SCENARIO WILL STILL BE IN PLACE ACROSS
REGION THROUGH THE PERIOD. BELIEVE A COMPROMISE BETWEEN FAN AVN AND
NGM MOS NUMBERS FOR TODAY HIGHS REASONABLE...AND IN LINE WITH
COORDINATION CALL ON TEMPS MADE TO BHM. WILL COMPROMISE BETWEEN FAN
AVN AND NGM MOS VALUES FOR REMAINDER OF PERIOD.
PRELIMINARY NUMBERS FOR COORDINATION PURPOSES ONLY...
BNA 086/063/086/064 14111
CSV 082/059/082/060 14111
.BNA...NONE.
14
JBW
FXUS64 KMRX 080651 tn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
940 AM EDT MON MAY 8 2000
CURRENTLY...
SURFACE PRESSURE AND WIND ANALYSIS PLACES A WEAK INVERTED TROUGH
AXIS FROM THE SOUTHERN FLORIDA PENINSULA...SSW TO BETWEEN KEY WEST
AND DRY TORTUGAS. SATELLITE INDICATES CONSIDERABLE CLOUDS STILL
LINGERING SE OF THE MIDDLE KEYS AS WELL AS OVER THE UPPER KEYS AND
ALSO TO THEIR SOUTHEAST. SCATTERED SHOWERS ARE OCCURRING IN THESE
CLOUDED AREAS...WITH A SLOW MOVEMENT TOWARD THE NORTHWEST. C-MAN
SITES HAVE REPORTED A SLIGHT INCREASE IN WIND THE PAST HOUR...
TO NEAR 15 KNOTS EXCEPT AT DRY TORTUGAS WHERE WINDS ARE LIGHTER TO
THE WEST OF THE TROUGH AXIS. 12Z SOUNDING 1 THSD FT WINDS AT KEY
WEST MEASURED ESE AT 15 KT...SIMILAR TO CURRENT 88D WIND PROFILE.
A MERCHANT VESSEL AT 12Z IN THE STRAITS SOUTH OF THE LOWER KEYS
REPORTED WIND E 17 KT AND SEAS 5 FT.
FIRST PERIOD FORECASTS...
THE LATEST RUC INDICATES THAT THE INVERTED TROUGH SHOULD MOVE WEST
TODAY...BUT ITS SURFACE WIND FIELD TO THE EAST OF THE TROUGH AXIS
LOOKS A BIT LOW ON SPEEDS GIVEN THE 12Z-13Z VERIFYING TIMES. AVN HAD
INDICATED A SLIGHT INCREASE IN WINDS TO THE EAST OF THE TROUGH
VERSUS TO THE WEST OF THE TROUGH. GIVEN THIS TREND...I MAY BOOST
COASTAL MARINE WINDS TO NEAR 15 KNOTS FOR KEYS PROPER AND STRAITS...
WHERE FLORIDA BAY AND OFFSHORE MAINLAND MONROE SHOULD BE A BIT
LIGHTER WIND SPEEDS DUE TO CLOSER PROXIMITY TO THE TROUGH AXIS.
FOR THE PUBLIC ZONES...AN UPDATE WILL BE MADE SHORTLY BEFORE NOON
TO TAKE OUT MORNING-AFTERNOON TRANSITIONAL WORDING. THE 12Z KEY WEST
SOUNDING IS A BIT WETTER THAN YESTERDAY...AND WITH SATELLITE SHOWING
MID AND UPPER KEYS STILL NEAR AND THREATENED BY SCATTERED SHOWERS.
IF 88D DOES NOT SHOW A DOWNWARD TREND IN SHOWERS BY 1130 AM..I MAY
KEEP A MENTION OF A BIT HIGHER POPS FOR MID AND UPPER KEYS THIS
AFTERNOON.
.EYW...NONE.
CLB
FXUS62 KMLB 081358 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
947 AM EDT MON MAY 8 2000
WILL ADJUST GULF COAST COASTAL ZONES A LITTLE AS A SEA BREEZE IS
POSSIBLE NEAR SHORE ALONG THE COLLIER COUNTY COAST BUT NO CHANGE
ELSEWHERE. LATEST SURFACE ANALYSIS INDICATES AT WEAK WAVE CAUGHT
IN EASTERLY LOW LEVEL WIND FLOW ALONG FLA SE COAST WITH ACTIVITY
IN FLA STRAITS AND NE PALM BEACH COUNTY. RUC PROGS AND SATELLITE
FORECAST AND VERIFY RESPECTIVELY DRIER AIR E OF SYSTEM AND UPPER
RAOB FROM MYNN BEARS THIS OUT TO SOME EXTENT. ZFP PACKAGE MAINLY
FOR E COAST TO BE REWORDED AS ACTIVITY SHOULD BE MAINLY W OF THE
COASTAL AREAS INLAND. STILL HAVE CAP AROUND 700 MB BUT NEED JUST
THE MID 80S TO POSSIBLY BREAK CAP AND POPS INLAND AND IN W SEEMS
OK AND A STRAY TSTM NOT IMPOSSIBLE.
.MIA...NONE.
FXUS62 KJAX 081344 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1110 AM EDT MON MAY 8 2000
THE MAIN FORECAST CONCERN THIS AFTERNOON WILL BE CENTERED AROUND THE
DEVELOPMENT OF CONVECTION OVER THE FORECAST AREA AND ITS ASSOCIATED
CONDITIONS.
THE CURRENT IR STLT LOOP SHOWS THE MCS WHICH DEVELOPED EARLY THIS
MORNING...MOVING SLOWLY NORTHEAST INTO SOUTHERN LAKE MICHIGAN AND
DIMINISHING. REGIONAL RADAR PLOTS SHOWING SHOWERS AND THUNDERSTORMS
OVER WESTERN AND CENTRAL UPPER MICHIGAN WITH SHOWERS AND
THUNDERSTORMS OVER SOUTHEAST WISCONSIN. UPPER MICHIGAN CONVECTION
FORMED IN AN AREA OF HIGH 850 MB DWPT AIR AROUND 10C...700/500 MB
LAPSE RATES AROUND 6C/KM AND IN AN AREA OF STRONG 700/500 MB DPVA IN
ADVANCE OF THE VORT CENTER MOVING OVER NORTHERN WISCONSIN. THE
PRECIPITATION OVER SOUTHEAST WISCONSIN IF FROM THE DIMINISHING MCS
THE DEVELOPED OVERNIGHT.
THE MODIFIED 12Z APX SOUNDING ALONG WITH RUC MODEL SOUNDINGS...
SUGGEST UNSTABLE CONDITIONS OVER THE FORECAST AREA THIS AFTERNOON.
CAPE VALUES WILL BE BETWEEN 1200 J/KG AND 1400 J/KG AND LI'S BETWEEN
-2 AND -5. THIS AFTERNOON 850 MB DWPTS WILL BE AROUND 12C TO 14C
WITH THE BEST THTE RIDGING REMAINING OVER THE SOUTHWEST PORTIONS OF
THE STATE. LIFT THIS AFTERNOON WILL BE MAINLY SUPPLIED BY STRONG
DPVA IN ADVANCE OF A VORT CENTER MOVING OVER CENTRAL LAKE MICHIGAN
INTO EAST UPPER MICHIGAN. 700/500 MB LAPSE RATES WILL BE AROUND 6 TO
7 C/KM THIS AFTERNOON AND WITH THE LOW LEVEL MOISTURE...INSTABILITY
AND LIFT WILL KEEP SHOWERS AND THUNDERSTORMS IN THE FORECAST ACROSS
THE FORECAST AREA.
.APX...NONE.
SWR
*** THE NWS IN MICHIGAN IS CONDUCTING A SURVEY TO LEARN MORE ABOUT
HOW OUR CUSTOMERS USE THE AREA FORECAST DISCUSSION (AFD). PLEASE
COMPLETE THIS SHORT SURVEY AT WWW.CRH.NOAA.GOV/APX/AFD_SURVEY.HTM.
THE FEEDBACK WE RECEIVE WILL HELP US PROVIDE A BETTER PRODUCT FOR
YOU. IF YOU HAVE QUESTIONS OR IF YOU NEED A PAPER VERSION OF THE
SURVEY...CONTACT BRUCE SMITH AT (517) 731-3384 EXT 766. THANK YOU
FOR YOUR PARTICIPATION.***
mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
1138 AM CDT MON MAY 8 2000
LATE MORNING UPDATE WILL BE ISSUED MAINLY TO TEND TO CURRENT
CONDITIONS, SPECIFICALLY WINDS, AFTERNOON TEMPS, AND CLOUDS ACROSS W
AND N PARTS OF AREA. COLD FRONT HAS MADE MUCH MORE PROGRESS INTO NW
OK THIS MORNING THAN WE HAD ANTICIPATED. ALTHOUGH 12Z ETA STALLS IT
NEAR ITS CURRENT POSITION, LATEST RUC CONTINUES IT WELL INTO
SW/CENTRAL OK BY 00Z - A DISTINCT POSSIBILITY WHICH IS SUPPORTED BY
CONTINUING PRESSURE RISES BEHIND IT. WILL LOWER AFTERNOON TEMPS IN W
AND N ZONES AS COOLER SURFACE AIR HOLDS ITS GROUND. THICKER BAND OF
AC/CI MOVING E ACROSS W AND N OK WILL RESULT IN MOSTLY CLOUDY SKIES
AT LEAST FOR A TIME, FURTHER DELAYING ANY RECOVERY OF TEMPS.
THE FARTHER S FRONTAL POSITION LIKELY WILL HAVE A SIGNIFICANT
BEARING ON THE UPDATED T-STORM OUTLOOK SCHEDULED FOR 1730Z. PROGGED
850 MB TEMPS - CORRESPONDING TO CAP LEVEL THIS MORNING - SHOW AN
OMINOUS COOLING UP N THRU EVENING, IMPLYING THAT THE CAP WILL WEAKEN
DURING THE AFTERNOON. PROFILERS SHOWING MID-UPPER WESTERLIES
CONTINUING TO STRENGTHEN ACROSS NW PARTS OF AREA AS NOSE OF STRONG
UPPER JET CONTINUES WORKING E ACROSS CENTRAL/SOUTHERN ROCKIES.
WEAKENING CAP, A MORE SOUTHERN FRONTAL POSITION, AND CONTINUING
IMPROVEMENT OF THE VERTICAL SHEAR PROFILE ALL POINT TO A CONTINUED
MODERATE RISK, BUT THE AREA MAY NEED TO BE ADJUSTED S. WE WILL
LAUNCH A SPECIAL SOUNDING AROUND 17Z, WITH PRELIM DATA HOPEFULLY
AVAILABLE JUST BEFORE THE UPDATED OUTLOOK. WE MAY NEED TO DO ANOTHER
FORECAST UPDATE AFTER EXAMINATION OF THE 18Z SOUNDING.
WILL ALSO NEED TO ADDRESS HEAVY RAIN/FLOODING POTENTIAL IN
NCENTRAL/NE PARTS OF AREA. LATEST QPFS FROM HPC ARE WITHIN REASON AS
UPPER FLOW MAY LEAD TO TRAINING OF ECHOES TONIGHT. IF THIS SCENARIO
UNFOLDS, THREAT WILL INCLUDE NOT ONLY FLASH FLOODING IN AFFECTED
AREAS, BUT POTENTIAL RIVER FLOODING DUE IN PART TO EXCESSIVE AMOUNTS
FROM A FEW DAYS AGO.
.OUN...
OK...NONE.
TX...NONE.
ok
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
320 PM EDT MON MAY 8 2000
CURRENTLY...
SURFACE INVERTED TROUGH HAS MOVED WEST SOME SINCE MORNING AS
EXPECTED AND INDICATED BY PREVIOUS RUC RUN...AND AS OF 3 PM HAD
JUST MOVED PAST DRY TORTUGAS WITH THE TROUGH AXIS EXTENDING TO THE
SOUTHWEST FLORIDA PENINSULA. C-MAN SITES ALONG THE FLORIDA REEF WERE
NOW RUNNING ESE 14-17 KT SUSTAINED GUSTS TO 20 KT (EXCEPT LONG KEY
WAS NOW RUNNING LOWER SPEEDS THAN EARLIER). DEWPOINTS REMAIN HIGH
OVER THE AREA...IN THE LOWER 70S. THUNDERSTORMS THAT HAVE FORMED
OVER THE SOUTH FLORIDA MAINLAND SHOULD NOT BE STEERED TOWARD THE
KEYS OR TOWARD FLORIDA BAY SINCE DEEP FLOW SURFACE TO 10 THSD FT IS
FROM THE SE TO S...AND IS SW ABOVE 10 THSD FT. ON THE OTHER HAND...
A FEW OUTFLOW BOUNDARIES MAY BE ABLE TO PROPAGATE INTO THE LOWER
LEVEL FLOW AND THESE MAY APPROACH THE KEYS...BUT THERE IS NO
EVIDENCE OF ANY AT THIS TIME. THICK CLOUDS OVER AND SE OF THE MID
AND UPPER KEYS HAVE THINNED SOME...STILL SHOWING CEILINGS 8 THSD FT
OR SO IN THIS AREA. RADAR SEEMS TO HAVE FEW SHOWERS IN THE CLOUDED
AREA...ALTHOUGH MAJOR AMOUNT OF CHAFF TODAY OBSCURES THE RADAR
SOMEWHAT.
FORECASTS...
THE MODELS AGREE ON THE SOUTHERN SHIFT IN THE ATLANTIC RIDGE THROUGH
48 HOURS...BRINGING THE RIDGE SOUTH TO ABOUT LAKE OKEECHOBEE BY
EARLY TUESDAY. THE AVN SURFACE AND BOUNDARY LAYER WINDS ARE CLOSER
TO CURRENT OBSERVED WINDS OVER MARINE AREAS...SO AS IS TYPICAL I
WILL LEAD TOWARD THE AVN WIND SPEEDS FOR COASTAL MARINE FORECASTS.
THERE IS ONLY ABOUT A 5 KNOT DIFFERENCE IN THE MODELS...WITH ETA
BEING THE LOWEST. WITH THE SURFACE RIDGE SHIFTING SOUTH BUT STILL
REMAINING NORTH OF THE KEYS...A HUMID SE FLOW WILL PERSIST AT LOWER
LEVELS WITH DEWPOINTS STAYING IN THE 70S...BUT SPEEDS MAY BE LIGHTER
ON TUESDAY NIGHT AND WEDNESDAY.
THE MAIN WEATHER FACTOR THEN...APPEARS TO BE THE MOVEMENT AND UVV
FIELDS IN ADVANCE OF A SHORT WAVE TROUGH AT 500-300 MB. THIS FEATURE
IS CURRENTLY IDENTIFIED AS A WEAK 300 MB LOW OVER LOUISIANA...BUT
MODELS INDICATE IT SHOULD GET IN PHASE WITH A PROGRESSIVE PATTERN
AND MOVE SOUTHEAST OVER THE GULF TOWARD FLORIDA AND THE KEYS.
THE AVN PROMOTES SOME UVV...AND QUITE A BIT OF 200 MB DIVERGENCE
OVER THE KEYS WELL AHEAD OF THE UPPER TROUGH AXIS BY END OF DAY
TUESDAY INTO WEDNESDAY. AVN ALSO IS WETTER THAN THE ETA. STILL...
UVV FIELDS OVER THE KEYS ARE NOT SO GREAT AS AREAS TO OUR NORTH...
SO WHILE I WILL LEAN TO THE HIGHER AVN-MOS POPS...I THINK 40 PCT FOR
WEDNESDAY IS ENOUGH. THE UPPER TROUGH MAY BE PAST BEFORE DAY IS OVER
WEDNESDAY..BUT I WON'T MENTION CLEARING YET AS IT IS TOO FAR INTO
FUTURE FOR TIMING TO BE CERTAIN. ALSO...WITH LIFTED INDEX MINIMUM
PATTERN FOLLOWING SE OVER THE GULF AND PASSING OVER THE KEYS AT
12Z WEDNESDAY...I WILL MENTION THE POSSIBILITY OF THUNDER FOR
TUE NIGHT INTO WED.
THERE ARE NO ARGUMENTS WITH ANY MOS TEMPS.
PRELIM TEMPS/POPS...
EYW BE 076/085 075/085 074 2234=
.EYW...NONE.
CLB
fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
730 AM EDT MON MAY 8 2000
...HEAT AND HEAVY CONVECTION SHUD GIVE WAY TO CHILLY OCEAN ASSISTED
OCCLUSION WEDNESDAY...
MODELS: RELYING HEAVILY AGAIN ON AVN SFC POSITS ALONG WITH 12Z/7
ECMWF THRU 72HRS. BEYOND 72 HOURS...LEAN HEAVILY ON MRF
AND NOT YET BUYING THE ECMWF FOR MOTHERS DAY WEEKEND.
PROBLEMS OF THE DAY: BACKDOOR CF...HEAVY CONVECTION AND HEAT.
1) AFTER HOPEFULLY REAPPRECIATING THE STRENGTH OF SPRINGTIME
BACKDOOR OCCURRENCE (SAT 5/6 WHERE BOS WAS AOB 59F ALL DAY)...
AND HOW THE ETA/NGM COULD NOT HANDLE THE STRENGTH OF THE
COOLING IN THEIR BL TEMPS AND BELIEF THAT THE AVN HAS BEEN
ON THE WHOLE OUTPERFORMING THE ETA ON SFC POSITS THIS WEEK OF
SHIFTS IN OUR FCST AREA...FCSTD TREND TO COLD IN BOS AND WAY
UNDER GUIDANCE AT BOS TUE/WED PER AVN.
ONCE THE BACKDOOR PASSES..DO NOT BLV IT CAN MOVE N OF ITS NEW
PSN WITHOUT BL WIND EXCEEDING 22 KTS.
THEREFORE...THE WED LOW WILL PROBABLY BE OCCLUDED AS IT COMES
THRU NEW ENGLAND WITH RATHER CHILLY NE-ESE FLOW ACRS ALL OF
OUR FA.
THIS IS A MAJOR DEPARTURE FROM THE 06Z ETA WHICH BLOWS THE HEAT
BACK INTO NEW ENGLAND WITH A VENGEANCE TUESDAY AFTERNOON...
POTENTIALLY HOTTER THAN YDY AND CERTAINLY HOTTER THAN TODAY.
2) SVR AND TSTMS: NO SPS ISSUED DUE TO AONLY A FEW REPORTS EXPECTED
BUT SKYWARN HAS BEEN ALERTED TO THE LIKELIHOOD OF TRW+ AND CHC
HAIL WITH GUST 40KTS. SHUD SEE ISO 2.5-3 INCHES IN 90 MIN PRD
SOMEWHERE BTWN RTE 2 IN NORTHERN SWD INTO N CT AND N RI...
BORDERED BY GREENFIELD...AYE-OWD-TAN-PVD-HFD-TO E SLOPES BERKS
18-23Z TDY. BLV THIS A GOOD DAY FOR A HANDFUL OF REPORTS 1 INCH
HAIL AND/OR GUSTS 40-50 KTS. PLS SEE UPCOMING UPDATED SPC TEXT.
WE HAVE COORD WITH SPC ON SVR THREAT. PW ALMOST 1.5" TDY! CELLS
DRIFT OUT 300 AT 20 KTS.
TUES AFTN: ETA SOUNDINGS HAVE DOUBLE THE WIND AT 600 MB UP TO
47 KTS AND BLV THAT SLIGHT RISK SVR NEEDS TO B CONSIDERED
FOR THE CT RVR VLY REGION (OCEAN LIKELY A COOLENT RETARDENT RI
AND ORH HILLS EWD INTO S NH). PW SLIGHTLY LESS (1.3) BUT GULLY
WASHERS APPEAR LIKELY A POSSIBLITY...POSSIBLY AIDED BY UPSLOPE RI
HILLS BUT MORE LIKELY CT RVR VLY. CELL MVMT ABT 2830?
3) HEAT: SINCE WE HAVE A QUICK START AND A WELL DEFINED NW FLOW AT
12Z WE EXPECT TEMPS TO REACH BTWN 83-87 IN BOS ARD 11 AM THEN
SEABRZ TO START A SLOW COOLING PROCESS FM QUINCY NWD STARTING
BTWN 15-17Z. IF FOR SOME REASON THE SEABRZ ONSET IS DELAYED
..BOS CUD HIT 90...BUT EXPECT THE 90F TO BE RESTRICTED
TO THE INTERIOR SUBURBS ABT 10MI INLAND. ONE NOTE ON THE
COOLING...IT WILL BE A SLOWER PROCESS THAN USUAL SINCE BL
WARMTH IS BEING CARRIED SEAWARD AT LEAST 5 OR 10 MI TIL ABT 15Z. A
WITNESS TO THIS IS THE IOSN3 CMAN TEMP OF 70F AT 11Z! BOS BUOY
ARD 15-20 MI OUT IS AT 57F. HEAT LOW AND DVLPG PRES FALL CENTROID
IN THE INTERIOR OF MA WILL ACCELERATE ELY WIND MID AFTN AND
AND WITH SFC TDS OVER THE WATER ALREADY IN THE 50S AND ETA SFC/
1000 MB MARKEDLY RISING THIS EVE...EXPECT LOW CLOUD AND FOG TO
SPREAD ASHORE WITH TEMP IN BOS DOWN TO 57 BY 22Z.
BACK TO THE HEAT: NEAR RECORD TO BOS NOT GUARENTEED...RECORD XPCTD
AT BDL AND RECORD/NEAR RECORD AT PVD. W SFC WIND AND M/SUNNY ARE
THE DRIVERS...IF SEA BREEZES HOLD OFF PAST NOON...THEN WE/RE IN
FOR RECORDS AT BOS/PVD.
TODAYS MAX TEMP RERS ARE
BOS 87-1964 XPCT WITHIN 2F
BDL 90-1936 XPCT TO EXCEED
PVD 88-1964 XPCT TO EQUAL OR EXCEED
ORH 90-1936
BLUE HILL 87-1964
TODAYS CALENDER RER MIN: MAY HAVE A RECORD WARM MIN AT BDL 65 -1930
OTRW BLV OCEAN AFFECTS MINS BY MIDNIGHT TNGT ATT OTHER 3 PRIME RER
SITES.
RISK OF 90 IN THIS HEAT EPISODE IS PROBABLY DONE AFTER TDY BASED
ON RECENT AVN MODEL TRENDS ALTHOUGH BDL HAS A CHC EITHER TUE
OR WED BUT DOUBT IT. PLS NOTE 06Z ETA BLOWS 90+ BACK THROUGHOUT
SNE TUESDAY...WE DISAGREE BASED ON AVN AND COLD SST/TIME OF YEAR
TENDENCIES AND THE FLAT WLY 5H FLOW.
QPF/QPS COORD WITH HPC/NERFC. POINT RFALL OF 3" IS EXPECTED
SOMEWHERE IN OUR FA AND OUR BASIN AMTS OF 3/4 INCH MAY B A BIT HIGH
AND PATH OF HEAVIEST MAY NEED ADJUSTMENT. WE FOCUSED JUST AHD OF
WSHIFT AS PROGGED BY THE 09Z RUC/ 00Z AVN.
YDY: RERBDL WAS ISSUED FOR YDY.
SCT BRF HEAVY SHWRS AND TSTMS ROAMED EWD ACRS THE REGION
ROUGHLY 19Z-01Z WITH ISO G ARD 30 KTS.
YDYS WDSPRD 90S WERE THE FIRST OF THE YEAR AND FOR
SPECIFIC SITES THE LAST PRIOR 90 IN 1999 WAS
BOS AUG 17
BDL SEP 3
PVD AUG 1
LR: AFTER COOL DOWN LATE THIS WK TENTATIVELY BLV THERE IS HOPE FOR
AT LEAST A DAY OF ABV NORMAL WARMTH RETURNING SNE SOMETIME
MOTHERS DAY WKND AND 00Z/8 MRF BACKS IT UP. SPEAKING OF LR...
JUST TO REITERATE THE MONTHLY CLASSIFICATION CRITERIA GUIDELINES
FOR THE 6-10 MEANS IN THE EONUS IN BOS/BDL FOR MAY (THEY VARY
BY MONTH AND SITE)...
TEMPS: MB MEANS A 5 DAY AVG MORE THAN -5 BLO NORM
B -5 TO -1
N -1 TO +1
A >1 TO 5
MA >+5
QPF: BOS BLO < 0.03 BDL BLO <0.05
NORM 0.03 TO 0.15 NORM 0.05 TO 0.18
ABV > 0.15 ABV >0.18
.BOX...NONE.
DRAG
ma
SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
915 AM MDT MON MAY 8 2000
...WILL UPDATE STATE AND TFX ZONE FORECASTS...
WEAK S/WV TROF MOVING ACROSS SRN MT WITH DIFFLUENT FLOW ALOFT ACROSS NRN
PORTIONS OF CWA. AMS SOMEWHAT UNSTABLE WITH 12Z TFX RAOB LI NEAR -1. NEW
ETA SHOWS SW AND E SLOPES REMAINING UNSTABLE THRU THIS AFTN...WITH WEAK
CAPES...<200 J/KG. HOWEVER...CANADIAN SFC HI OVER SRN ALTA AT 14Z
SENDING COOL DRY AMS OVER N CENTRAL ZONES. LATEST RUC SHOWS 700 S/WV
TROF MOVING INTO CENTRAL MT BY 00Z WITH MID LVL MOIST. FOR NOW WILL HOLD
OFF ADDING AFTN CONVECTION TO N CENTRAL MT TODAY DUE TO COOLER LOW LVL
AMS. WILL UPDATE SW ZONES TO INCLUDE ISOLATED TSTMS THIS AFTN. FOR
TONIGHT AND TUE NEW ETA SHOWS NEG TILTED S/WV TROF MOVING THRU CWA...BUT
MID LVL WINDS ARE WLY WITH LITTLE UVV INDICATED ALONG E SLOPES. WILL
EXAMINE THIS CLOSELY THIS AFTN. EYSSAUTIER
EXTENDED DISCUSSION...NEW UKMET AND MRF GENERALLY SIMILAR WITH TWO SHORT
WAVES MOVING INTO GREAT BASIN. THE MAIN SHORT WAVES MAY REMAIN SOUTH OF
MONTANA...BUT STATE REMAINING IN COOL UNSETTLED WEATHER IN 3 TO 5 DAY
PERIOD. ECMWF BRINGS IN FIRST SHORT WAVE LATE WEDNESDAY OR THURSDAY WITH
UPPER RIDGE BUILDING ON FRIDAY. WILL LEAN TOWARDS THE MRF AND UKMET.
OARD
GTF BW 062/038 058/033 060 16145
CTB BW 058/034 052/029 056 16145
HLN EW 062/038 058/036 062 16255
BZN EW 058/038 055/033 058 16476
WEY WR 048/032 045/028 048 16688
DLN EW 056/040 054/035 057 16365
HVR BW 064/035 060/035 063 16136
LWT BW 058/034 056/034 058 16136
mt