AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSONVILLE FL
955 AM EST SUN DEC 5 1999
SHORT TERM...SATELLITE SHOWED THE STRATO-CU STILL ADVECTING OVER THE
FORECAST AREA (FA) BUT NOT AS EXTENSIVE AS FRIDAY NIGHT. THE
WRINKLE IS THAT RADAR SHOW THAT A FEW COASTAL SHOWERS HAVE POPPED
UP...BUT THIS IS NOT UNEXPECTED. AT 12Z MSAS SHOWED WEAK SURFACE PVA
WITH WEAK TO MODERATE MOISTURE CONVERGENCE JUST OFF THE NORTHEAST
FLORIDA AND SOUTHEAST GEORGIA COASTS. HOWEVER THE RUC AND MESO ETA
SHIFT THE WINDS TO A MORE SOUTHERLY DIRECTION BY LATE AFTERNOON
WHICH SHOULD MOVE THE ACTIVITY ONSHORE NORTH OF OUR CWA...SO
WILL REMOVE THE MENTION OF SHOWERS IN THE ZONES BUT KEEP THEIR
MENTION IN THE COASTAL WATERS. TEMPERATURES SEEMS TO BE A LITTLE
HIGHER THAN FORECAST SO WILL BUMP THE MAX TEMPERATURES A TAD FOR
SOME LOCATIONS TODAY. THE REMAINDER OF THE EARLY MORNING PACKAGE
LOOKS OK.
.JAX...
GA...NONE.
FL...NONE.
BLS
FXUS62 KTBW 051515 fl
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
1010 AM EST SUN DEC 5 1999
EXTENSIVE DECK OF CLOUDS REMAIN TRAPPED BELOW STRONG SUBSIDENCE
INVERSION AT 750 MB. FLOW ABOVE INVERSION GRADUALLY BECOMING
S/SW...WITH BOUNDARY LAYER WINDS SLOWLY VEERING TO MORE SOUTHERLY
COMPONENT. ALTHOUGH BREAKS OF SUNSHINE WILL OCCUR ACROSS CWA THIS
AFTERNOON...SATELLITE TREND FAVORS CONTINUATION OF CONSIDERABLE
CLOUD COVER DESCRIPTOR. CLOUD COVER WILL LIMIT RAPID RISE OF
TEMPS...BUT BELIEVE FORECAST MAXS WILL BE REACHED BY LATE AFTERNOON.
WILL MONITOR TEMPS FOR EARLY AFTERNOON ZONE UPDATE IF RISE DOES NOT
MATERIALIZE. FEW LIGHT SHOWERS/SPRINKLES OCCURRING OVER SE ZONES
HAVE BEEN WEAKENING LAST FEW HOURS...THEREFORE CURRENT POP FORECAST
OK.
MARINE...BROAD RIDGE AXIS HAS REACHED CENTRAL FLORIDA COASTAL
WATERS...RESULTING IN A WEAKENING OF SURFACE WINDS. LATEST RUC
DEPICTS SITUATION WELL...WITH LIGHT WINDS OVER NORTHERN MARINE ZONE
THROUGH AFTERNOON AND E/SE GRADIENT STILL PREVALENT SOUTH OF
SEBASTIAN. WILL DROP WINDS WITH UPDATE...ESPECIALLY N OF COCOA
BEACH. SEAS STILL A LITTLE HIGHER THAN WIND JUSTIFIES DUE TO SMALL
SWELL COMPONENT.
.MLB...NONE.
WIMMER/SPRATT
FXUS62 KEYW 051458 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
945 AM EST SUN DEC 5 1999
COLD FRONT (ALONG EAST LA - EAST MS) MOVING EAST AT 15 KT AND IS ON
PACE TO REACH THE WESTERN PORTION OF OUR CWA BY THIS EVENING...IN
GOOD AGREEMENT WITH ETA/AVN. (NGM LOOKS A LITTLE SLOW). LATEST RUC
DID A GOOD JOB AT FORECASTING THE LIGHT RAIN TO OUR WEST. 'TIS
ASSOCIATED WITH MOISTURE FLUX CONVERGENCE AND WEAK ISENTROPIC LIFT
ALONG THE WARM FRONT. THE RUC FORECASTS THIS RAIN TO REMAIN LIGHT
AND NOT MAKE MUCH EASTWARD PROGRESS. THEREFORE...CURRENT ZONES LOOK
GOOD AND WILL ONLY MAKE COSMETIC CHANGES.
CWF: WINDS ARE STILL HOWLING AROUND 20 KT AT THE BUOYS...WITH SEAS
UP TO 7 FEET. HOWEVER...WINDS SHOULD DECREASE A LITTLE THIS
AFTERNOON WITH A WEAKENING PRESSURE GRADIENT. THIS IS FORECASTED BY
THE ETA (WHICH HAS HAD THE BEST WIND FORECAST SO FAR)...AND IS ALSO
SUPPORTED BY BUOY DATA TO THE WEST. WILL KEEP CURRENT ADVISORY
CRITERIA AS IS.
.TLH...SCA TODAY APALACHICOLA TO DESTIN.
FOURNIER
FXUS62 KMFL 051439 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
234 PM CST SUN DEC 5 1999
12Z CHARTS SHOWED NEARLY VERTICALLY STACKED UPPER LOW CONTINUING TO
PROGRESS NE THROUGH SE MO. WV VERIFIES THIS WELL WITH NICE
CLOSED VORT MAX NEARING ST LOUIS AS OF 19Z. NRN STREAM SHORTWAVE
CONTINUES TO MOVE ACROSS SRN ONTARIO. SURFACE LOW ASSOCIATED WITH
THIS SRN SYSTEM CONTINUES TO MOVE NE AND AT 18Z WAS LOCATED TO
THE EAST OF KCMI NEAR THE IN BORDER. NICE DEFORMATION ZONE ON NORTH
SIDE OF THIS SYSTEM BEING AIDED BY COUPLING OF RR QUAD OF NRN STREAM
JET OVER NE IA INTO WI AND LF QUAD OF SRN STREAM JET OVER MID
MISSISSIPPI VALLEY. ALL OF THIS IS HELPING TO GIVE ACCUMULATING
SNOWS ACROSS SOUTHEASTERN 1/2 OF CWA...WHILE THE REST OF THE CWA WAS
SPARRED THE BRUNT OF THIS SYSTEM AS DRY AIR HAS FILTERED INTO FROM
THE NW. A FEW LOCATIONS IN CENTRAL CWA HAVE SEEN UP TO 2-4 INCHES OF
SNOW ACCUMULATION...MAINLY IN THE QUAD CITIES AREA. TIGHT PRES
GRADIENT HELPING TO PRODUCE BREEZY CONDITIONS AS WELL TODAY.
SURFACE RIDGE AXIS CURRENTLY EXTENDS ACROSS THE HIGH PLAINS OF ERN
DAKOTAS DOWN THROUGH WRN KS. TEMPS THIS MORNING WERE QUITE COLD NEAR
SURFACE RIDGE AXIS WITH MANY LOCATIONS IN THE SINGLE DIGITS AND
TEENS. DOWN STREAM...UPPER LEVEL RIDGE BUILDING INTO THE
PLAINS REGION...AS NEXT WEAKER SHORTWAVE MOVES THROUGH THE
INTERMOUNTAIN REGION. NEXT LARGER MORE POWERFUL SYSTEM EVIDENT
BEHIND THIS MOVING TOWARD THE PAC NW COAST...WITH STRONG 150KT JET
AIMED TO HELP DIG SYSTEM INTO THE WEST COAST.
FORECAST CHALLENGES INCLUDE TIMING END OF SNOW THIS EVENING...CLOUD
TRENDS TONIGHT...AND TEMPS TONIGHT THROUGH MONDAY. ALSO TIMING OF
NEXT SYSTEM FOR LATE THIS WEEK.
12Z MODELS SEEMED TO INITIALIZED FAIRLY WELL ON CLOSED LOW OVER MO...
BUT THE RUC SEEMED TO HAVE THE LOCATION AND STRENGTH DOWN THE BEST.
ETA SEEMED TO HAVE THE BEST HANDLE ON THE UPPER LEVEL RIDGING
BEHIND THIS SYSTEM. AVN SEEMED TO INITIALIZE BEST WITH 850 MB THERMAL
FIELDS TO THE NW AND THIS IS REFLECTED WITH FAN SUPERIOR PERFORMANCE
WITH LOWS THIS MORNING. AT THE SURFACE...NGM INITIALIZED AND
CONTINUES TO DO WELL AT 18Z WITH THE PLACEMENT OF THE SURFACE LOW
NEAR THE IL/IN BORDER...AS WELL AS THE RIDGE AXIS TO OUR WEST AND
CONSEQUENT PRESSURE GRADIENT BETWEEN THE TWO. ONLY MODEL TO PICK ON
SNOW AMOUNT ACROSS CENTRAL CWA THIS AFTERNOON WAS THE ETA WITH THE
RUC DOING GOOD WITH THE TIMING AND EXTENT OF THE PRECIP...WITH OTHER
MODELS UNDERDOING PRECIP AMOUNTS COMPLETELY. MODELS NOT DOING WELL IN
LOW CLOUD DECK ASSOCIATED WITH LLVL COLD POCKET CURRENTLY MOVING
SOUTH ACROSS NE IOWA WRN WI BEHIND DEPARTING SYSTEM. WITH THE NGM
VERIFYING THE CLOSEST. WILL SIDE WITH RUC IN TIMING OF END OF PRECIP
THIS EVENING...AND WITH A BLEND OF NGM/AVN FOR CLOUD COVER. WITH FAN
TEMPS LOOKING THE BEST TONIGHT.
TONIGHT...
BIG QUESTION IN SHORT TERM IS TIMING OF PRECIP TO END ACROSS ERN CWA.
VORT MAX SHOULD CONTINUE TO LIFT NE ACROSS CENTRAL IL INTO THE
EVENING HOURS...GIVING GOOD EASTWARD PROGRESSION OF SNOW BAND THROUGH
THE ERN ZONES. LATEST RADAR TRENDS INDICATE THAT SOUTHERN END OF BAND
IS MAINLY -SN AND IS MOVING QUICKLY TO THE EAST. IR SAT TRENDS SHOW
GOOD WARMING OF CLOUD TEMPS INDICATING WEAKENING OF DYANAMIC LIFT AS
WELL. THIS SHOULD GIVE MOST LOCATIONS IN ERN ZONES WITH LIGHT SNOW
ENDING FROM THE WEST...WHILE FAR NE COUNTIES WILL SEE MOD SNOW WITH
ACCUMULATIONS OF ANOTHER INCH BEFORE ENDING FROM THE WEST BY 00Z.
WILL WORD ZONES IN THE EAST TO REFLECT THIS DIMINISHING TREND WITH AN
EVENING WORDING. WILL WAIT UNTIL LAST MINUTE TO ISSUE WORDING FOR
THESE ZONES BASED ON RADAR TRENDS/SPOTTER REPORTS. NEXT QUESTION
TONIGHT IS LOW TEMPS. VERY LARGE RANGE OF SNOWCOVER COULD HAVE
PRONOUNCED EFFECT ON LOW TEMPS. MOST AREAS IN THE NW DIDN'T SEE ANY
SNOW AT ALL. HOWEVER...THIS AREA WILL SEE THE CALMEST WINDS. WHILE
AREAS IN THE CENTRAL AND SE ZONES WILL SEE GRADIENT WINDS RELAXING
LATE TONIGHT. MODELS DIVERGE ON LOW CLOUD COVER AS WELL...WITH THE
ETA THE MOST BULLISH IN KEEPING 80%+ RH IN TO CENTRAL/ERN ZONES
THROUGH 12Z. IR/VIS SAT INDICATES THAT CLOUDS ARE LIKELY ASSOCIATED
WITH 850MB COLD POOL. ALL MODELS INDICATE THAT THIS COLD POOL SHOULD
SHIFT EAST OF CWA DURING THE NIGHT. WILL GO WITH PARTLY CLOUDY SKIES
IN THE WEST EARLY BECOMING MOSTLY CLEAR LATE. FOR THE EASTERN ZONES
MID LEVEL CLOUDS SHOULD DISSIPATE BY LATE EVENING AT THE LATEST...SO
WILL GO WITH BECOMING MOSTLY CLEAR OVERNIGHT. MOS OUTPUTS AGREE IN
DECOUPLING WINDS. NGMMOS OVERDID TEMPS LAST NIGHT NEAR RIDGE AXIS
AROUND 3 DEGREES...SO WILL UNDERCUT IN MOST ZONES...AND FOLLOW CLOSER
TO FAN NUMBERS. MAY SEE EVEN COLDER TEMPS IN AREAS THAT HAVE THICK
SNOW COVER.
MONDAY...
SKIES SHOULD BE CLEAR WITH WINDS BECOMING SOUTHWEST AS SURFACE HIGH
SHIFT TO THE SE OF CWA. TEMPS WILL CONTRAST BETWEEN AREAS THAT
HAD SNOW COVER AND THOSE THAT DIDN'T. 850 TEMPS WARM TO BETWEEN 2
AND 3C BY LATE IN THE DAY ACROSS WESTERN ZONES. WILL LIKELY SEE
TEMPS APPROACHING FWC NUMBERS IF NOT A LITTLE WARMER OUT WEST. WILL
UNDERCUT FWC/FAN NUMBERS IN AREAS WITH SNOWCOVER..AS TEMPS SHOULD
BE HELD TO THE LOWER 30S.
MONDAY NIGHT AND TUESDAY...
MID/HIGH LEVEL CLOUDS ASSOCIATED WITH WEAK SHORTWAVE MOVING OUT OF
ROCKIES INTO THE PLAINS SHOULD GIVEN PARTLY CLOUDY SKIES. TEMPS
MONDAY NIGHT SHOULD BE COLDER AGAIN IN AREAS THAT STILL HAVE
REMAINING SNOW COVER AND IN ERN ZONES WHERE WINDS WILL DECOUPLE THE
BEST...WITH WRN ZONES SEEING WARMER CONDS AS WINDS WILL STAY UP AT 5
KTS OR MORE HELPING TO PREVENT GOOD RAD COOLING ALONG WITH THING.
CLOUDS SHOULD CLEAR EARLY TUESDAY AS UPPER LEVEL FORCING WEAKENS.
NEXT MAJOR TROUGH POISED TO DIG INTO THE WEST COAST. AT THE
SURFACE WINDS SHOULD SWITCH TO THE SOUTH ON TUESDAY AHEAD OF NEXT
WEAK SURFACE TROUGH THAT SLOWLY MOVES EAST ACROSS THE PLAINS.
SOUTHERLY WINDS SHOULD BRING WITH IT GOOD WARMUP FOR MOST LOCATIONS
DURING THE DAY SO WILL FAVOR WARMER FAN NUMBERS.
EXTENDED...
DPROG/DT INDICATES THAT LATEST AVN RUN IN AGREEMENT WITH YESTERDAY'S
BELIEF THAT NEXT TROUGH SHOULD DIG MORE INTO THE SW U.S. 12Z AVN
ALSO SHOWS SYSTEM TO BE DEEPER THAN 00Z MRF. GIVEN GOOD TRACK RECORD
OF AVN THIS FALL HAVE NO QUALM IN BELIEVING A CONTINUED
INTENSIFICATION AND DEEPENING OF THIS NEXT SYSTEM. WITH A DEEPER
TROUGH DEVELOPING IN THE WEST...WE SHOULD SEE SLIGHTLY WARMER
CONDITIONS ON WED THAN TUE AS WAA CONTINUES DESPITE THE INCREASE
IN MID AND HIGH CLOUD COVER...WHICH MATCHES WELL WITH GOING
FORECAST. NEXT QUESTION BECOMES TIMING AND DURATIONS OF PRECIP FOR
NEXT SYSTEM. LATEST EURO/UKMET IN REMARKABLE AGREEMENT AND IN LINE
WITH LATEST AVN IN TROUGH DIGGING INTO 4 CORNERS REGION BY EARLY WED.
THIS SLOWER DEEPER SOLUTION WOULD ARGUE FOR HOLDING OFF PRECIP UNTIL
THURS ACROSS CWA...AS BEST LIFT REMAINS ACROSS SRN PLAINS. COLD
FRONTAL BOUNDARY SHOULD ALSO REMAIN TO THE WEST ACROSS IA/NE BORDER
UNTIL MAIN ENERGY EJECTS OUT OF PLAINS ON THURSDAY...AND SHORTWAVE
PHASES WITH NRN STREAM WAVE. THIS SYSTEM LOOK REMARKABLY SIMILAR TO
LAST ONE...AND WOULDN'T BE SURPRISED TO SEE VERY SIMILAR TRACK OF
UPPER LOW AND SURFACE LOW AS MRF INDICATING. THEREFORE WILL GO WITH
CHANCE OF RAIN ON THURS...WHICH SHOULD MIX WITH AND CHANGE TO ALL
SNOW FRI BEFORE ENDING LATE FRI. BUT SYSTEM SHOULD MOVE QUICKLY AS
NEXT MAJOR STORM MOVING INTO SW U.S. WILL HELP EJECT IT. ACTIVE
PATTERN LOOKS TO CONTINUE WELL INTO NEXT WEEK.
...PRELIMINARY GUIDANCE FOR COORDINATION ONLY. OFFICIAL FORECASTS ARE
ARE CONTAINED WITHIN QUAD CITIES ZONE FORECAST.
DBQ BU 018/034 021/044 029 77000
CID BU 015/036 022/045 031 77000
MLI BU 015/033 021/043 030 77000
BRL BU 019/034 023/045 032 77000
.DVN...
IA...NONE.
IL...NONE.
MO...NONE.
CROSBIE
FXUS63 KILX 052025 il
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS
855 PM EST SUN DEC 5 1999
...UPDATED FCST TO END SNOW NRN 1/3 AND CLEAN UP WORDING SRN 2/3 OF
CWA...
LATEST SAT/RADAR MOSAIC LOOPS OF SW PART OF GREAT LAKES AT 02Z
SHOWS MAIN AREA OF SNOW HAS MOVED OUT OF CNTL LWR MI. HOWEVER...
AREA OF LIGHT SNOW ASSOCIATED WITH INTERACTION OF NRN STREAM SHTWV
AND SRN STREAM SHTWV CONTINUES TO MOVE ENE FROM NRN IN/IL INTO SW
LWR MI. 18Z ETA PCPN AREA MATCHES THE ACTUAL PCPN AREA BEST OF ANY
OF THE OTHER MODELS (AVN/12Z ETA/NGM/23Z RUC). IT MOVES THE PCPN
ACROSS CWA BY MIDNIGHT BUT KEEPS IT MOSTLY SOUTH OF I-96 (MKG TO LAN
LINE).
THERE IS ALREADY A MID-LAKE LAKE EFFECT SNOW BAND BUT WITH NORTH
WINDS BELOW SUBSIDENCE INVERSION... THIS WILL NOT BE A PROBLEM FOR
OUR CWA. ALSO... SINCE TEMPS AT TOP OF INVERSION AFTER 06Z WILL BE
WARMER THAN -10C... WILL NOT HAVE SEEDING FROM MID CLOUDS LIKE WE DO
NOW... SO EITHER WAY... THIS WILL NOT BE A PROBLEM FOR GRR CWA.
BOTTOM LINE... MOSTLY CLDY NRN 1/3 OF CWA OVERNIGHT.
OCNL LIGHT SNOW ENDING CNTL CWA WITH MINOR ACCUMULATIONS
OCNL LIGHT SNOW ENDING SE CWA WITH AN INCH OR LESS ACCUMS
.GRR...NONE.
WDM
FXUS63 KAPX 060109 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
810 PM EST SUN DEC 5 1999
SYNOPTIC SNOW HAS DIMINISHED AND MOVED OUT OF THE REGION FASTER THAN
PREVIOUSLY ANTICIPATED AS THE SFC LOW HAS MADE STEADY EASTWARD
PROGRESS THIS EVENING. ALSO...DRIER AIR IS PUSHING INTO THE REGION
FROM THE NW...TENDING TO ERODE THE WRN EDGE OF THE PRECIP. RUC
SOUNDINGS SHOW INVERSION HEIGHTS OF ONLY 900 MB WITH INCREASINGLY
DRIER AIR ABOVE OVERNIGHT. THIS SEEMS REASONABLE LOOKING AT UPSTREAM
KMQT RADAR SHOWING ONLY VERY SHALLOW...DISORGANIZED LAKE EFFECT SNOW
OVER UPR MI ATTM.
HAVE UPDATED ALL ZONES TO EITHER DIMINISH PRECIP TO FLURRIES OR
REMOVE PRECIP COMPLETELY FOR THE REMAINDER OF THE NIGHT. WILL KEEP
MENTION OF FLURRIES IN FOR ERN UPR AND NW LOWER MI AROUND TVC AND
CAD DUE TO N FLOW OFF THE LAKES. WILL ALSO KEEP MENTION OF A FEW
FLURRIES FOR FAR SE PORTIONS OF THE CWA AS SOME LOW LEVEL MOISTURE
LINGERS IN THIS REGION UNTIL LATE TONIGHT.
.APX...NONE.
EME
FXUS63 KDTX 052359 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
658 PM EST SUN DEC 5 1999
CHANGEOVER FROM RA TO SN IS NOT GOING AS CLEANLY AS PLANNED. 21Z RUC
HAS EASILY THE BEST HANDLE ON LOW LVL THERMODYNAMICS AMONG THE
MESOSCALE MODELS...BUT EVEN IT DID NOT COOL OFF SFC TEMPS FAST ENUF.
STILL...IT IS THE ONLY MODEL I/VE SEEN THAT ACKNOWLEDGES THE FZRA
POSSIBILITY THAT HAS ALREADY BEEN REALIZED IN TUSCOLA CO. ZFP HAS
ALREADY BEEN UPDATED TO REFLECT RECENT PRECIP TYPE TRENDS. RUC
SOUNDINGS SUGGEST COLD PUNCH AT 900MB AND BLO WL SLOW SUFFICIENTLY
TO ALLOW A MORE GRACEFUL PRECIP CHANGE FAR SOUTH...IF AND WHEN THAT
HAPPENS. WL NOT ISSUE WSW ATTM GIVEN PATCHY AND BRIEF NATURE OF FZRA.
.DTX...NONE.
ZOLTOWSKI
FXUS63 KAPX 052145 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1105 AM EST SUN DEC 5 1999
LK EFFECT CLOUDS AND WIND ARE MAIN UPDATE CONCERNS
15Z SFC ANALYSIS SHOWS 1006 MB LOW JUST NORTHEAST OF GEORGIAN BAY
WITH COLD FRNT DRAPED BACK INTO ERN TX. IR SAT...RADAR MOSAIC...AND
SFC OBS ALL POINT TO RAINY SUNDAY ALG AND AHEAD OF SFC FRONT...WITH
-SN OBSERVED BEHIND FRNT IN IA...WRN MO...AND ERN KS. UPR MI IS
BETWEEN THE LOW PRESSURE AREA AND A 1025 MB SFC HIGH NEAR KFAR AND
AS A RESULT OF FAIRLY TIGHT PRESSURE GRADIENT IS EXPERIENCING SOME
GUSTY WINDS THIS MORNING. GUSTIEST WINDS ARE FOUND ALONG LK SUPERIOR
WHERE P59...CMX...AND ANJ HAVE REPORTED WINDS AOA 20 KT.
PER RUC AND MESOETA SFC TO BLYR WINDSPEEDS AND SFC ANALYSIS...EXPECT
GUSTY WINDS IN THE 10 TO 20 KT RANGE TO CONTINUE THROUGH MAJORITY OF
AFTERNOON BEFORE SLACKENING. IN ADDITION TO NW WINDS...THERMAL TROF
AT H8 AS DEPICTED BY ETA...NGM...AND AVN (ALTHOUGH ETA SHOWS A COLD
BIAS BY 2-4 DEG C PER MORNING SOUNDINGS AT INL AND GRB) THROUGH THE
DAY AND STEADY TEMPERATURES PER FLP GUIDANCE FOR ENTIRE U.P...WILL
KEEP TEMPS STEADY AROUND CURRENT READINGS.
DESPITE LATEST IR SAT SHOWING CLOUDS OVR NRN LK SUPERIOR BREAKING UP
A BIT...WILL CONTINUE TO GO WITH MOSTLY CLOUDY FOR ALL ZONES.
THINKING IS THAT H8 TEMPS NEAR MINUS 10 DEG C (PRODUCING DLT T/S
AROUND 14-15 ACROSS THE LK) WILL HELP TO SUSTAIN LK CLOUDS FOUND OVR
ENTIRE UPR MI ATTM. ALSO DUE TO THE INSTABILITY...FLURRIES AND LGT
SN SHOWERS POSSIBILITY WILL CONTINUE FOR THE REMAINDER OF AFTN. 88D
SHOWING LGT RETURNS ATTM AND THAT SHOULD STAY THE CASE SINCE
INVERSION HTS WILL REMAIN AROUND 3K FT THROUGHOUT DAY OVR NRN FA PER
RUC FCST SOUNDINGS.
.MQT...NONE.
JLA
FXUS63 KGRR 051603 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
912 PM EST SUN DEC 5 1999
LOW LEVEL SHRA FROM OFF THE OCEAN CONTINUES TO GET SHUNTED TO THE
EAST AS WNDS AT THE LOWER LEVELS HAVE EVOLVED A BIT MORE OF A
WESTERLY COMPONENT DUE TO THE APPROACH OF UPPER TROF. THERE4...BASED
ON LATEST 88-D TRENDS WILL GO WITH LOWER POPS AT THE COAST AND HIER
INLAND DUE TO APPROACH OF FRNT AND ASOCIATED MOISTURE AS ILLUSTRATED
BY LATEST RUC AND MESO-ETA. WNDS TO STAY UP ALL NITE AS 40 PLUS KT
8H JET MOVES ACROSS. FOG SHULD NOT BE A PROBLEM.
TEMPS...WILL UP MINS ACROSS THE BOARD BASED ON LATEST OBS AND DEW
PTS.
CWF...WITH GOOD 8H JET MOVG OVER HEAD AND SSTS NOT COLD ENUF TO
PREVENT IT FROM MIXING TO THE SFC. WILL INCREASE WNDS TO 25 KT BY
MORNING. WILL CONTEMPLATE INCREASING TO 30 KT DURG MON AFTER LOOKING
AT OTHER GUIDANCE.
.ILM...SMALL CRAFT ADVISORY FROM SURF CITY NC TO SOUTH SANTEE RIVER SC.
DCH
FXUS62 KMHX 060130 nc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE/SPARTANBURG SC
832 PM EST SUN DEC 5 1999
00Z SFC ANALYSIS SHOWS FRONT IN CENT TN AND WRN AL...WITH PRECIP
BAND WELL AHEAD OF IT. A RECENT INCREASE IN CONVECTION IN SERN AL
APPEARS TO INDICATE THAT A WEAK WAVE IS DEVELOPING IN THAT
REGION...PROBABLY IN RESPONSE TO SHORTWAVE ENERGY ROUNDING THE BASE
OF TROUGH AND RIGHT ENRANCE REGION OF UPPER JET. THIS FEATURE MAY
ACT TO SLOW THE FORWARD PROGRESSION OF PRECIP BAND. AS WOULD BE
EXPECTED...AXIS OF HIGHER SFC DWPTS ARE EXPECTED TO SHIFT EAST WITH
TIME (AS RUC AND 18Z ETA SHOW) AND MOVE OVER AT LEAST THE SRN HALF
OF CWA OVERNIGHT. DON'T EXPECT MUCH IN THE WAY OF STRONG CONVECTION
OVERNIGHT. DESPITE GOOD SHEAR...AIRMASS TOO STABLE. HOWEVER...CAN'T
RULE OUT A RUMBLE OF THUNDER OR TWO. IF CURRENT TIMING IS
CORRECT...SHOWERS WILL BE TAPERING OFF OR ENDING OVERNIGHT WEST TO EAST.
WILL UPDATE ZONES A LITTLE EARLY TO RAISE POPS EAST OF MTNS TO
CATEGORICAL. DEPENDING ON TRENDS...WILL PROBABLY HAVE TO UPDATE
ZONES AGAIN BEFORE LEAVING AT MIDNIGHT TO ACCOUNT FOR LACK OF PRECIP
IN THE WEST.
LOWS WILL NEED TO BE RAISED TO AS FRONT WILL ONLY BE KNOCKING ON THE
DOOR OF THE MTNS AROUND DAYBREAK. CURRENT DWPTS ARE RANGING THROUGH
50S CWA-WIDE. WITHOUT ANY CHANGE IN AIRMASS...LOWS EAST OF THE MTNS
WILL PROBABLY NOT GO LOWER THAN THE MID 50S.
.GSP...NONE.
MOYER
FXUS62 KCHS 052017 sc
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE COLUMBIA SC
1242 PM EST SUN DEC 5 1999
.UPDATE...
MST CLD CVR MOVG NE AWAY FROM CENT CWA. SOME DIURNAL CU FORMING
THOUGH. ALSO...TEMPS ALREADY REACHING FCST MAXES W AND CENT CWA. AGS
MAY REACH RECORD MAX OF 77. WINDS PICKING UP A BIT.
.PREV DISC...
SKC OVR CAE CWA ATTM. CLDS ALG THE CST AND INTO SE GA...WITH WDLY
SCT SHRA NR CST. 12Z CHS SOUNDING INDICATES MOISTURE 900-750 MB WITH
WIND DIR SW AT THAT LEVEL. SATL TRENDS INDICATE NE MVMT OF
CLDS...WITH APPEARANCE THAT CSRA WILL SEE LESS CLDNS THIS AFTN THAN
REMAINDER CWA. LTST RUC SUPPORTS MOISTURE STREAMING NE...AND
CONFINES PCPN TO NR THE CST. SO...WILL WORD LESS CLDS CSRA...AND
REMOVE POP FOR THEM. WILL ALSO RAISE MAX TEMPS CSRA DUE TO MORE SUN.
.CAE...NONE.
MILLER
FXUS62 KCAE 051531 sc
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1029 AM EST SUN DEC 5 1999
SKC OVR CAE CWA ATTM. CLDS ALG THE CST AND INTO SE GA...WITH WDLY
SCT SHRA NR CST. 12Z CHS SOUNDING INDICATES MOISTURE 900-750 MB WITH
WIND DIR SW AT THAT LEVEL. SATL TRENDS INDICATE NE MVMT OF
CLDS...WITH APPEARANCE THAT CSRA WILL SEE LESS CLDNS THIS AFTN THAN
REMAINDER CWA. LTST RUC SUPPORTS MOISTURE STREAMING NE...AND
CONFINES PCPN TO NR THE CST. SO...WILL WORD LESS CLDS CSRA...AND
REMOVE POP FOR THEM. WILL ALSO RAISE MAX TEMPS CSRA DUE TO MORE SUN.
.CAE...NONE.
MILLER
FXUS62 KCHS 051502 sc
AREA FORECAST DISCUSSION...CORRECTED POP STATEMENTS
NATIONAL WEATHER SERVICE MORRISTOWN TN
1015 PM EST SUN DEC 5 1999
06/02Z PRE-FRONTAL SURFACE TROUGH POSITIONED ACROSS EASTERN KENTUCKY
AND EASTERN TENNESSEE...EXTENDING SOUTHWEST TO THE FLORIDA
PANHANDLE. LIGHT SHOWERS WERE OCCURRING WITHIN THIS SURFACE
FEATURE...WITH ISOLATED AREAS OF MODERATE RAIN IN SECTIONS OF THE
FORECAST AREA.
UPSTREAM OF THE SURFACE TROUGH EXTENDING INTO THE MISSISSIPPI RIVER
VALLEY...THE AREA APPEARS DRY SLOTTED WITH RESPECT TO PRECIPITATION.
HOWEVER...PLENTY OF POST-FRONTAL LOW CEILINGS EXTEND INTO ARKANSAS
AND SOUTHEAST MISSOURI...WHERE THE 06/06Z RUC PROGS SYNOPTIC-SCALE
FORCED DESCENT CONSIDERING UPPER-LEVEL JET CORE IS WELL TO THE EAST.
CURRENT THINKING FOR TONIGHT WILL BE TO LOWER POPS. THE OVERNIGHT
POP UPDATE WILL RANGE FROM 30 IN THE SOUTHERN VALLEY...TO 60 FOR THE
CENTRAL SMOKYS AND NORTHEAST MTS (CONSIDERING LOW-LEVEL MOISTURE AND
BETTER UPSLOPE FLOW DEVELOPING AFTER MIDNIGHT).
IN TERMS OF TEMPERATURES...OVERNIGHT MINS LOOK REALISTIC WITH FROPA
NOT EXPECTED BEFORE 6/12Z.
.MRX...
NC...NONE.
TN...NONE.
VA...NONE.
DM
FXUS64 KOHX 060259 tn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
930 PM EST SUN DEC 5 1999
PRE-FRONTAL SURFACE TROUGH POSITIONED ACROSS EASTERN KENTUCKY AND
EASTERN TENNESSEE...EXTENDING SOUTHWEST TO THE FLORIDA PANHANDLE.
LIGHT SHOWERS WERE OCCURRING WITHIN THIS SURFACE FEATURE...WITH
ISOLATED AREAS OF MODERATE RAIN IN SECTIONS OF THE FORECAST AREA.
UPSTREAM OF THE SURFACE TROUGH EXTENDING INTO THE MISSISSIPPI RIVER
VALLEY...THE AREA APPEARS DRY SLOTTED WITH RESPECT TO PRECIPITATION.
HOWEVER...PLENTY OF POST-FRONTAL LOW CEILINGS EXTEND INTO ARKANSAS
AND SOUTHEAST MISSOURI...WHERE THE 06/06Z RUC PROGS SYNOPTIC-SCALE
FORCED DESCENT CONSIDERING UPPER-LEVEL JET CORE IS WELL NORTHEAST OF
THE FORECAST AREA.
CURRENT THINKING FOR TONIGHT WILL BE TO DROP POPS (20 FOR THE
SOUTHERN VALLEY...AND 40 FOR THE NORTHEAST FORECAST AREA) ONCE THE
BULK OF PRECIPITATION ASSOCIATED WITH PREFRONTAL TROUGH EXITS BEFORE
MIDNIGHT (ZONE UPDATE WILL PR0BABLY BE SENT BETWEEN 10 AND 11 PM
EST).
IN TERMS OF TEMPERATURES...OVERNIGHT MINS LOOK REALISTIC WITH FROPA
NOT EXPECTED BEFORE 6/12Z.
.MRX...
NC...NONE.
TN...NONE.
VA...NONE.
DM
FXUS64 KMRX 052106 tn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
1045 AM EST SUN DEC 5 1999
WAVE OF LOW PRESS TO MOVE NE ALONG FRONT ACRS ONT AND INTO QUE TDY.
FRONT TO MOVE SLOWLY EAST ACRS THE EASTERN GREAT LKS TDY DUE TO UPR
LVL FLOW BEING NEARLY PARALLEL TO IT. THIS FRONT FORECAST TO START TO
DROP DOWN ACRS THE FA OVRNITE TONITE.
12Z RUC INDICATES SOUTHERLY FLOW TO INCREASE TDY WITH HIGHS IN THE
M40S-M50S. NO FRONTAL PCPN INDICATED THRU 00Z THOUGH. 11Z LAMP DATA
SHOWS FIRST MEASURABLE PCPN INTO THE ST LAW VLY BETWEEN 00Z AND 06Z
TONITE. START TIME FOR PCPN APPEARS TO BE AROUND 00Z IN ST LAW
VLY...AROUND 06Z CHAMP VLY...IN BETWEEN IN THE ADIRONDACKS...AND
AFTER 06Z ELSEWHERE. MODELS INDICATE THAT UPR LVL DYNAMIX WILL NOT
COME INTO PLAY ACRS THE FA UNTIL AFT 06Z TONITE.
ATTM...SCT LT PCPN INDICATED ON AREA 88DS MOVING NE ACRS FA IN H85
WAA/POSITIVE MOISTURE ADVECTION PATTERN. THESE SHRA TO DEPART THE
ENTIRE FA AFT 18Z TDY. PESKY FOG STUBBORN TO SCOUR OUT AND MAY LEAVE
IN MTN ZONES AND SOUTHERN VT FOR A TIME THIS AFT.
SAT PIX INDICATE BREAKS IN CLD COVER MOSTLY FILLING IN...BUT FEEL
BEST CHC FOR ANY PERIODS OF SUN LATER THIS AFT WILL BE IN SOUTHERN
VT.
HAVE INDICATED ABOVE TRENDS IN LATE MORNING UPDATE OF THE WORK ZONES.
WILL HOLD REAL ZONES UNTIL AFTER 11 AM SO THAT SHRA CAN CLEAR AS MUCH
OF THE FA AS POSSIBLE.
.BTV...NONE.
MURRAY
FXUS61 KBTV 051409 vt
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
305 AM EST MON DEC 6 1999
BOTH RUC AND MAPS MODELS INDICATE TWO DISTINCT AREAS OF HIGHER
SFC-H85 THETA-E EARLY THIS MORNING...THE FIRST WAS JUST OFFSHORE OF
THE S CAROLINA COAST EXTENDING NE INTO ERN NC AND THE SECOND FROM
APALACHICOLA FL INTO PARTS OF S GEORGIA. BTWN THESE AREAS IS THE CHS
FORECAST AREA WHICH WILL BE AFFECTED BY THIS SPLIT PRIOR TO THE WLY
FLOW AND SURGE OF LOWER THETA AIR LATER THIS AFTN. BOTH THE ETA/AVN
INDICATE A CHC OF ISOLD TSTMS AROUND MIDDAY FROM THE CENTRAL S
CAROLINA COAST NEWD. GIVEN THE CURRENT TRENDS AND DATA FROM THE
MESO MODELS...TSTMS APPEAR UNLIKELY IN SC ZONES 043>045 AND 050.
POPS WILL BE DISTRIBUTED FROM 20/30 PCNT EARLY IN INLAND SE GEORGIA
TO 40/50 ERN S CAROLINA. SFC FRONT IS ON TRACK WITH 6 HR GUIDANCE
POSITIONS AND SHOULD PUSH OFF THE COAST AOB SUNSET. HIGH TEMPS TDA
SHOULD BE AROUND 70 COAST AND MID 60S WELL INLAND.
HIGH PRES BLDG IN TONIGHT AND TUE...RETURN TO MOSTLY CLEAR SKIES AND
TEMPERATURES REASONABLY CLOSE TO CLIMO. EXTENDED FCST LOOKS GOOD...
SLOW TEMP MODERATION AND ONSHORE CONVERGENT LOW LVL FLOW INCREASING
CHCS OF CLOUDS AND PSBL SHOWERS FRI.
CWF: ONLY MINOR ADJUSTMENTS THIS PACKAGE. WILL CONTINUE MARGINAL SCA
TDA WITH FLOW SHIFTING N TONIGHT. WITH VWP 40 KT AT 2 KFT...SHOULD
BE A GUSTY MORNING ON THE CHS HARBOR AND WILL RAISE SCA. EXPECT TO
SEE A SURGE WITH THE N WINDS LATER TONIGHT GIVEN THE PROGGED RAPID
DROP IN SFC DEW POINTS AND REASONABLY TIGHT SFC PRES GRADIENT. THANKS
FOR COORD ILM.
PRELIM CCF
CHS EU 071/039 060/034 063 244-000
SAV EU 070/038 062/032 064 2430000
CHL EU 069/046 058/042 060 244-000
NBC EU 069/040 061/035 062 244-000
.CHS...
SC...SMALL CRAFT ADVISORY S SANTEE RIVER TO SAVANNAH GA OUT 20 NM.
GA...SMALL CRAFT ADVISORY SAVANNAH GA TO ALTAMAHA SOUND GA OUT 60
NM.
RVT
FXUS62 KCAE 060659 sc
TEXAS/OKLAHOMA PANHANDLES AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AMARILLO TX
410 AM CST MON DEC 6 1999
SATL SHOWS HIGH CLOUDS STREAMING E AHEAD OF SHRTWV MOVING INTO WRN CO
THIS MORNING. THIS SHOULD MAKE FOR PTLY SUNNY DAY. SHRTWV MOVES INTO
IA BY THU AS NEXT POTENTIAL WINTER STORM BEGINS TO TAKE SHAPE OFF CA
COAST. ASSCD WEAK SFC TROUGH ON LAPS FROM NEB PNHDL INTO ERN CO WILL
MV E ACROSS AREA TODAY. 06Z RUC BRINGS WIND SHIFT WITH IT ACROSS NRN
ZNS BY 18Z. TEMPS TODAY WILL AGAIN BE HIGHLY DEPENDENT ON SNOW COVER.
PLAN ON TRIMMING EVEN A FEW DEGREES MORE OFF CURRENT FCST HIGHS
WHERE SNOWPACK EXISTS. THIS WILL MAKE FOR A WIDE RANGE IN MAX TEMPS
WITH LARGE VARIATIONS POSSIBLE EVEN WITHIN A SINGLE COUNTY.
WEAK WRLY FLOW AT SFC AND ALOFT TONIGHT SHOULD ALLOW FOR MORE GOOD
RADIATIONAL COOLING WITH LOWS TOUCHING 20 AGAIN IN SOME AREAS. MORE
HIGH CLOUDS PLANNED FOR TUE AS FLOW BEGINS TO BUCKLE OUT W AND PAC
SHRTWV DIGS TOWARD FOUR CORNERS REGION. TEMPS SHOULD BE ABLE TO CLIMB
INTO 50S WITH SRLY FLOW INCREASING.
IN EXTENDED...00Z AVN DIGS UPPER LOW INTO SE NM BY WED EVE WITH GULF
OPENING UP AHEAD OF IT. WILL INTRODUCE POPS FOR WED GIVEN AMOUNT OF
MOISTURE THAT COULD BE THROWN UP AHEAD OF DIGGING SYSTEM IN NM. THE
MORE THE LOW DIGS AND SLOWER IT MOVES THE MORE SFC WINDS WILL BACK
AND INCREASE RAIN CHCS. WILL START CONSERVATIVE AND LIMIT TO ERN ZNS
FOR NOW BUT THIS COULD BE PUSHED EVEN FURTHER W WITH TIME.
WE FAVOR SLOWER AND DEEPER SOLUTION OF UKMET AT THIS POINT. NOGAPS
LOOKS TOO FAR S. NEW MRF QUICKLY LIFTS LOW NE INTO SE KS ON THU
HOWEVER IF SLOWER UKMET IS RIGHT THIS COULD MEAN ANOTHER GOOD SHOT OF
HEAVY SNOW FOR TX PNHDL THU. MAIN DIFFERENCE WITH THIS STORM FROM
LAST IS ADDED IMPACT OF GULF MOISTURE. WILL INCREASE POPS INTO CHC
CATEGORY WITH POTENTIAL FOR EVEN HIGHER AND MENTION RAIN CHANGING TO
SNOW WED NIGHT/THU. LOOKS TO BE A BREAK ON FRI BEFORE ANOTHER STORM
APPROACHES OVER THE WEEKEND.
.AMA...
TX...NONE.
OK...NONE.
COBB
FXUS64 KMAF 061005 tx
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
1005 AM EST MON DEC 6 1999
COLD FRONT CURRENTLY EXTENDING FROM SE GA TO EASTERN FLORIDA
PANHANDLE. SATELLITE AND RADAR MOSAIC INDICATE LEADING EDGE OF THICK
CLOUDS AND SCATTERED LIGHT RAIN/SHOWERS APPROACHING NORTHERN CWA.
PRE-FRONTAL TROUGH WILL DROP THROUGH CWA TODAY..ENHANCING LIFT AND
RESULTING IN SCATTERED SHOWERS. HAVE UPDATED ENTIRE ZFP RECENTLY TO
INCLUDE GREATER DETAIL ON TIMING OF CLOUDS AND SHOWERS BASED ON
SATELLITE/RADAR EXTRAPOLATIONS AND LATEST RUC FORECAST.
MARINE...AFTER A BRIEF LULL OF WINDS OVER PORTION OF NORTHERN MARINE
LEG...WINDS HAVE RETURNED TO NEAR 15 KT. EXPECT A FURTHER SMALL
INCREASE THIS AFTERNOON AS GRADIENT TIGHTENS IN ADVANCE OF FRONT.
WINDS CURRENTLY A LITTLE WEAKER OVER SOUTH LEG...AND SHOULD REMAIN
LESS THAN THAT OVER N FLORIDA WATERS...THUS HAVE DROPPED SCEC SOUTH
OF COCOA BEACH.
.MLB...NONE.
WIMMER/SPRATT
FXUS62 KTAE 061500 fl
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1100 AM EST MON DEC 6 1999
SHORT TERM CONCERN IS LOW LAKE CLOUDS
ANALYSIS AT 15Z SHOWS WRN MQT FA NOW UNDER INFLUENCE OF STRETCHED
OUT RIDGE FM NEAR JAMES BAY CURVING SOUTH INTO ERN MO...NEAR STL.
LIGHT NORTHERLY FLOW OFF LK SUPERIOR OVR FA THROUGH THE NIGHT AND
TRAPPED LOW LEVEL MOISTURE BENEITH STRONG SUBSIDENCE INVERSION PER
12Z INL SOUNDING...HAVE HELPED ENHANCED MVFR CIG CLOUDS THROUGH THIS
MORNING.
CLOUD SHIELD ATTM ORIENTED FM SERN WI OVR TO NRN LOWER MI AND NORTH
INTO UPR MI AND SRN ONTARIO. AS FLOW TURNS TO SOUTHERLY DIRECTION
BEHIND RIDGE SHIELD OVR NORTH CENTRAL WI ALREADY BEGINNING TO ERODE
PER 10Z-14Z AWIPS IR LOOP IMGRY. AS DAY PROCEDES...CLOUDS SHOULD
START TO ERODE OVR WRN INTO CNTRL FA...ALBEIT SLOWLY. RUC FCST
SOUNDINGS SHOW DRYING TREND AROUND H95 FM WEST TO EAST ACROSS FA
TDY. CMX DWPT DEPRESSION AT 950 MB IS 2 DEG AT 15Z AND 4 DEG BY 21Z.
MQT IS SIMILAR AND ERY IS A LITTLE SLOWER AT CLEARING OUT AS IT ONLY
REACHES A DWPT DEPRESSION OF 2 BY 00Z...THIS IS EXPECTED WITH THE
LIGHT NORTHERLY FLOW TURNING TO SOUTHWEST BY 00Z AS WELL. RUC
SCENARIOS AGREE WITH NGM RH AT 950 MB...AS AOB 70 PERCENT MOVES TO
IWD BY 18Z...MQT BY 22Z...AND ERY BY 00Z.
AS ANTICIPATED WITH LGT FLOW AND LOW CLOUDS FOR MUCH OF THE FA
TODAY...TEMPS WILL RISE VRY LITTLE FM PRESENT READINGS. HOWEVER...IN
THE WRN YOOP WHERE SUN WILL LIKELY BREAK THROUGH THIS AFTN READINGS
IN THE LOWER 30S SEEM REASONABLE.
PER 88D RETURNS OR LACK THERE OF AND CONTINUING LOWERING INVERSION
HTS WL REMOVE MENTION OF SCT SHSN FOR ERN COUNTIES AND GO WITH JUST
A FEW FLURRIES FOR REMAINDER OF AFTN.
.MQT...NONE.
JLA
FXUS63 KAPX 061543 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1025 AM CST MON DEC 6 1999
VERY LITTLE IN THE WAY OF UPDATES NEEDED AT MIDDAY. 12Z RAOBS SHOW
HIGH TEMPERATURES GENERALLY IN THE BALLPARK...AND WE'VE GOTTEN A
GOOD START WITH SUNSHINE AND DECENT MIXING.
SHORTWAVE TROF IN COLORADO CONTINUING TO TRACK EAST. RUC SHOWING
QUITE A BIT OF UPPER LEVEL DIVERGENCE AND ASCENT ON 330K SFC...
WHICH CORRELATES WELL TO THICKER HIGH CLOUD DECK. THIS FORCING
ADVANCE NE INTO SRN MN THIS AFTN. THIS TREND IS ALREADY HANDLED
WELL...SO WILL JUST MAKE SOME MINOR CHANGES
.MSP...NONE
DAVIS
FXUS63 KDLH 060926 mn
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
1051 AM EST MON DEC 6 1999
DRY SLOT SEEN ON VIS...IR...AND WTR VAPOR IMAGERY MOVING NE ACRS
CENTRAL NY STATE ATTM. THIS SPELLS LESS PCPN FOR WESTERN ZONES THAN
PREVIOUSLY EXPECTED AND MAYBE EVEN A FEW BRIEF BREAKS OF SUN FROM
THE CHAMP WESTWARD TDY. SAW A FEW GLIMPSES OF BLUE OUT THE WINDOW
HERE AT BTV EARLIER.
SEVERAL WAVES OF LOW PRESS RIDING NE ALONG THE FRONT DOWN THE ST
LAW VLY TO OUR WEST. FRONT IS ALREADY SAGGING THROUGH THE ST LAW RVR
VLY AND TEMPS SHOULD BE FALLING THERE TDY. WK LOW PRESS NOTED DOWN IN
VA STARTING TO GET ORGANIZED...BUT MAIN LOW PRESS AREA STILL UP IN
THE NORTHEAST THOUGH. MOSTLY SHRA BEHIND THE FRONT...BUT REAL COLD
AIR STILL STUCK UP IN ONT AND WESTERN QUE...SO NO SNOW TDY ACRS THE
FA.
BEST CHC FOR ANY MEASURABLE PCPN ON 11Z LAMP DATA APPEARS TO BE DOWN
IN SOUTHERN/EASTERN VT. THIS LOOKS GOOD BASED ON COMPOSITE 88D
LOOP. AGREE WITH GYX THAT THE FIRST BAND OF "PRE-FRONTAL" PCPN WAS
CAUSED BY WAA...NOTED ALONG WITH GOOD MOISTURE ADVECTION AT H85 IN
00Z ETA.
09Z RUC HAS SFC LOW CURRENTLY OVR EASTERN LK ONT MOVING EAST ACRS
NORTHERN NY/NORTHERN VT TDY...AS THE FRONT SAGS SE THROUGH MOST OF
THE FA BY AROUND 21Z. UPR TROF ALSO FORECAST TO MOVE EAST ACRS THE
EASTERN GREAT LKS REGION TDY. TEMPS TO GET UP TO AROUND 50 DEG IN
SOUTHERN VT THIS AFT. FRONT HAS PLENTY LOW LVL MOISTURE TO WORK
WITH...SO EXPECT SOME REDEVELOPMENT OF LT SHRA THIS AFT ALONG AND
AHEAD OF IT AND THE H5 TROF.
HAVE INCORPORATED ABOVE THINKING INTO WRKZFP. ONLY COSMETIC CHANGES
TO LATER PERIODS RIGHT NOW.
FYI...WE/VE BEEN HAVING SOME MINOR POWER PROBLEMS WITH KCXX 88D SINCE
THIS PAST WEEKEND. YOU MAY SEE SOME OF THE LIGHTER RADAR ECHOES COME
AND GO AS THE POWER OUTPUT FLUCTUATES. THE GROUND CLUTTER PATTERN
AROUND THE RADAR MAY INCREASE TO SOME ABNORMALLY HIGH VALUES ALSO. EL
TECHS HAVE PARTS AND WILL BE FIXING THE RADAR PROLLY TOMORROW...AFTER
THE SIG WX PASSES.
WORK ZONES OUT...WILL MAKE A FEW CHANGES TO THEM BASED ON LATEST OBS
TRENDS AND 14Z LAMP DATA. RUNNING LATE TDY...SO TIME TO GO...
.BTV...NONE.
MURRAY
FXUS61 KBTV 060855 vt
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1145 AM EST MON DEC 6 1999
SCT SHSN/FLURRIES CONTINUING ACROSS SOUTHERN AND EASTERN CWA NOW IN
WRAP-AROUND MOISTURE. MAIN QUESTION FOR THE AFTERNOON WILL BE DEGREE
AND TIMING OF CLEARING AND TIMING ON ELIMINATION OF SHSN.
CLEARING JUST ENTERING NORTHERN PORTION OF CWA. 925 MB RH MOISTURE
FIELD ON RUC SHOWS DRYING TO CONTINUE THIS AFTERNOON...MAINLY ACROSS
WESTERN PORTION OF CWA. A FEW BREAKS NOW EVIDENT ACROSS NORTHERN
GENESEE COUNTY AND SHIAWASSEE COUNTY. WILL CALL FAR NORTHWEST
COUNTIES BECOMING PARTLY SUNNY. FURTHER SOUTH...WILL CALL FOR MOSTLY
CLOUDY...WITH A FEW SUNNY BREAKS ACROSS WESTERN PORTION OF
CWA...WHILE KEEPING ENTIRE EAST CLOUDY.
WHERE PRECIP IS CURRENTLY ONGOING AND ACROSS EASTERN CWA...WILL
CARRY A MENTION OF FLURRIES FOR EARLY AFTERNOON. DESPITE THIS MORNING/S
PRECIP...DID NOT NOTE ANY MEASURABLE PRECIP IN ASOS BUCKETS ACROSS
CWA. OF COURSE...CANT RULE OUT A HUNDREDTH HERE OR THERE...BUT
FLURRIES LOOK GOOD FOR EARLY AFTERNOON. LAKE EFFECT CHANCES LOOK
MINIMAL FOR THUMB AS FLOW BACKS TO NORTHWEST THROUGH AFTERNOON AND
INVERSION HEIGHTS ARE AT ABOUT 900 MB.
ONLY CHANGE TO TEMPS WILL BE ACROSS THUMB...WHERE NORTHERLY WIND OFF
LAKE HURON HAS TEMPS IN MID 30S...SO WILL GO WITH LOW TO MID 30S
THERE.
.DTX...NONE.
OKEEFE
FXUS63 KGRR 061622 mi
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
310 PM CST MON DEC 6 1999
MAIN FCST CONCERN IS TEMPS IN THE NEAR TERM...AND CHCS FOR PCPN IN
THE EXTENDED. PREFFERED THE AVN MODEL...WHICH HAS BEEN DOING WELL
LATELY AND CONTINUED TO SHOW GOOD CONSISTENCY WITH THIS RUN.
FIRST FEATURE OF NOTE IS SHORTWAVE MOVING THROUGH NEB. THE LATEST
RUC TAKES THIS CIRCULATION ACRS NRN IA/SRN MN OVRNT. ALTHOUGH LOW
LAYERS REMAIN DRY...ENOUGH UPPER LEVEL MOISTURE AND FORCING PRESENT
FOR A FAIRLY THICK CI/CS DECK TONIGHT. AS THIS SYSTEM EXITS...SHOULD
SEE SOME CLEARING OVER WRN ZONES. SFC TROF ACRS DAKOTAS WILL LIKELY
PULL OUT SLIGHTLY...BUT SHOULD STILL REMAIN WEST OF THE AREA TONIGHT
AS MEAN FLOW REMAINS NORMAL TO THE ROCKIES.
AS WRN SYSTEM DIGS INTO THE GREAT BASIN TUESDAY/TUES NT...LEE SIDE
TROFFING WILL STRENGTHEN. THIS WILL PUT MN BACK INTO A LOW LEVEL
WAA PATTERN...WITH 850 TEMPS RISING A FEW DEGREES FOR TOMORROW.
THEREFORE...WILL GENERALLY GO A LTL ABV GUIDANCE FOR TUESDAY.
ON WEDNESDAY...TROF BEGINS TO PULL OUT INTO THE SRN PLAINS. LOW
DEEPENS OVER TX/OK AREA...WITH INVERTED TROF NORTH INTO MN. 850
THETA-E ADV INCR LATE IN THE DAY...BUT WILL HOLD OFF ON MENTIONING
ANY PCPN UNTIL THE WED NT/THU PD. SHOULD BE A BIT COOLER WITH CLOUDS
AND LESS MIXING.
MED RNG MODELS DIVERGE GREATLY IN THE EXTENDED. LATEST ECMWF NOT
AVAILABLE...AND 12Z UKMET IN MUCH DIFFERENT THAN AVN AT 72 HOURS.
BASICALLY...12Z AVN FOLLOWED THE OLDER MRF/ECMWF...SO IT APPEARS
THAT THIS MAY BE THE PREFFERED SOLUTION. EXPECT RAIN TO DEVELOP WED
NT PER 1000-850MB AND 850-700MB THICKNESSES. AS SYSTEM LIFTS NE
THURSDAY THICKNESSES FALL...SO PCPN WILL CHANGE OVER FROM RAIN TO
SNOW. CURRENT INDICATIONS ARE THAT HEAVIER SNOW WILL REMAIN SOUTH
OFMPX FCST AREA ATTM AS BEST ARE OF MID LEVEL DEFORMATION MOVES
ACRS IA.
.MSP...NONE
DAVIS
FXUS63 KDLH 061658 mn
CENTRAL PENNSYLVANIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
305 PM EST MON DEC 6 1999
...WORK ZONES OUT AS PHLADMCTP...
88D SHOWING A BAND OF -SHRA OVER CENTRAL MTNS AS OF 3 PM. EXPECT
THESE SHOWERS TO DRY UP AND MOVE EAST OF THE AREA BY EARLY EVENING.
MID LVL CIRCULATION CLEARLY EVIDENT IN IR IMAGERY OVER OHIO THIS
AFTN. LATEST RUC TAKES THIS FEATURE SOUTHEAST ACROSS THE MTNS OF W
VIRGINIA THIS EVENING...WHERE SHOWERS SHOULD BE MOST NUMEROUS.
ACROSS CENTRAL PA...FEEL SCT SHOWER ACTIVITY WILL PERSIST ACROSS THE
OROGRAPHICALLY FAVORED N AND W MTNS UNTIL LATE EVENING WHEN TROUGH
AXIS PASSES TO OUR EAST AND INVERSION FALLS BLW 8H. AS FOR PRECIP
TYPE...WILL MENTION EARLY EVENING RAIN SHOWERS FOR THE MTNS N OF
IPT. OTHERWISE...SHOULD BE COLD ENOUGH FOR SHSN OVER THE LAURELS AND
NW MTNS BY DUSK.
TUESDAY...SKIES BECOME MSUNNY AS S/WV DEPARTS INTO NEW ENGLAND AND
DRIER AIR WORKS IN FROM THE OHIO VALL. 9H TEMPS SUGGEST HIGHS FROM
L40S MTNS TO NR 50 IN THE SUSQ VALL.
TUESDAY NITE/WED...IDEAL RADIATIONAL COOLING TUE NITE AS SFC HI
BUILDS OVER THE REGION. UNDER CLEAR SKIES AND LIGHT WINDS...EXPECT
TEMPS TO FALL BLW MOS GUIDANCE. HI PRES AT SFC AND ALOFT WILL
PROVIDE FAIR AND MILD CONDITIONS FOR WED AFTER A CHILLY START.
EXTENDED...THURS LOOKS VERY WARM AS HI DRIFTS TO OUR EAST AND SKIES
REMAIN MSUNNY. MEDIUM RANGE MODELS IN GOOD AGREEMENT ON BRINGING
NEXT S/WV INTO THE REGION BY FRIDAY WITH A CHANCE OF SHOWERS. A FEW
RAIN/SNOW SHOWERS SEEM POSSIBLE OVER THE MTNS ON SATURDAY AS ONLY
SLIGHTLY COOLER AIR WORKS IN BEHIND LO PRES.
.CTP...NONE.
FITZGERALD
FXUS61 KPHI 062000 pa
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
325 PM EST MON DEC 6 1999
COORD WITH GYX.
ATTM...SFC COLD FRONT MOVING ACRS NY STATE...AS SEEN ON VIS SAT PIX.
FRONT IS ALREADY BY SLK/UCA AND IS JUST MOVING INTO THE PLB/BTV
AREA NOW. FRONT SHOULD BE IN THE MPV/RUT AREA BY AROUND 22Z. NEAREST
SHSN STILL UP NEAR YWA WITH JUST SCT SHOWERY PCPN BEHIND FRONT.
COMPOSITE 88D IMAGERY SHOWS MOST OF THE STEADIER PCPN WILL BE PASSING
BY TO THE SOUTH OF THE FA THIS EVENING.
PREFER 12Z NGM SOLN WITH SFC LOW PRESS TRACKING ACRS NORTHERN NEW ENG
THIS EVENING VS. AVN/ETA SOLN OF TRANSFERRING MAIN ENERGY TO
COASTAL LOW (TO THE EAST OF NYC) BY 00Z TONITE. SO...SFC SYS TO MOVE
EAST ACRS NORTHERN NEW ENG TONITE WHILE COASTAL LOW STARTS TO
INTENSIFY IN THE GULF OF ME BY LATER TONITE. THIS COASTAL STORM
FORECAST TO MOVE UP INTO THE CANADIAN MARITIMES DURING THE DAY ON
TUE. HI PRESS RIDGE TO MOVE ACRS THE FA FROM THE WEST ON TUE
NITE/WED. UPR TROF TO MOVE THROUGH THE FA TONITE/EARLY TUE FROM THE
EAST.
FA BASICALLY UNDER H85 CAA THROUGH 12Z WED. TEMPS WON/T GO TOO
MUCH HIR THAN TUE MORNING/S HIGHS. H85 LOW LVL MOISTURE WILL BE
HANGING AROUND THROUGH 00Z WED IN NE/NC VT. WILL HANG ONTO PCPN (IN
THE MTNS MOSTLY) ON TUE. H85 TEMPS GO NEGATIVE IN NY STATE THRU 12Z
TUE. WILL INDICATE A CHANGE TO SN IN NY STATE OVRNITE TONITE AND
RA/SN IN VT FOR TUE.
HI PRESS TO CLEAR THINGS OUT OVRNITE ON TUE NITE...AND WED LOOKS TO
BE A NICE DAY.
IN THE EXTENDED PERIOD...HI PRESS WILL BE MOVING THROUGH FOR THU.
NEXT LOW PRESS SYS MOVES ACRS THE GREAT LKS REGION ON FRI...BEFORE
PASSING BY TO THE EAST ON SAT. WILL CONTINUE CHC OF SHRA ON THU...AND
SINCE THERE MAY BE SOME SHSN ON THE BACK SIDE OF THIS SYS...WILL
MENTION SHRASN ON SAT.
WORK ZONES OUT...WILL MAKE A FEW CHANGES TO THEM AFTER LOOKING AT
LATEST RUC AND LAMP DATA...AS WELL AS SFC OBS.
.BTV...NONE.
MURRAY
FXUS61 KBTV 061552 vt