Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/19/15
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1017 PM MST MON NOV 16 2015
.UPDATE...
ISSUED AT 903 PM MST MON NOV 16 2015
MODELS ARE TRENDING SLIGHTLY SOUTHWARD AND SLOWER WITH THE TRACK
OF THE UPPER LOW ACROSS NEW MEXICO INTO THE TX/OK PANHANDLES BY
12Z TUES. GETTING A BIT OF A BREAK ACROSS THE I-25 CORRIDOR...BUT
AS UPPER LOW SKIRTS TO OUR SOUTH...THIS SHOULD FILL IN AGAIN AS
INTENSE TROWAL WRAPS UP AND SPREADS EASTWARD AROUND NORTHWEST SIDE
OF THE UPPER LOW. DID A MAJOR OVERHAUL TO HEADLINES...BRINGING
MORE OF THE RATON MESA REGION AND SOUTHERN I-25 CORRIDOR
WALSENBURG TO TRINIDAD TO A WINTER STORM WARNING. INITIAL WARM
START...AND SLOW COOL DOWN ACROSS THE PLAINS IS MAKING WINTER
WEATHER HIGHLIGHT DECISIONS DIFFICULT. EXTENSIVE WIND AND A PERIOD
OF HEAVY SNOW IS EXPECTED TUESDAY MORNING...BUT WARM GROUND MAY
PREVENT A LOT OF LIFTING OF THE FRESH SNOW LIMITING POOR
VISIBILITIES TO DIRECTLY UNDER THE HEAVIER SNOW BANDS. HOWEVER
CONDITIONS ACROSS THE EASTERN COUNTIES...RUNNING FROM
KIOWA...PROWERS...BENT...SOUTHERN OTERO AND NORTHWEST BACA
COUNTIES WILL HAVE TO BE WATCHED CLOSELY...AS IT COULD BE VERY
NEAR WHITE OUT CONDITIONS AT TIMES IF TEMPERATURES CAN STAY COLD
ENOUGH ON TUESDAY. FOR NOW...HAVE SPREAD THE WINTER WEATHER
ADVISORIES OUT TO ALL OF SOUTHEAST COLORADO PLAINS. LATER SHIFTS
WILL HAVE TO MONITOR LOCATIONS UNDER THE TROWAL OUT THAT WAY FOR
POSSIBLE UPGRADE TO A WARNING AT A LATER POINT. THESE AREAS LOOK
TO GET HIT HARDEST STARTING TUESDAY MORNING. -KT
UPDATE ISSUED AT 540 PM MST MON NOV 16 2015
THE MAIN UPDATE HAS BEEN TO STRENGTHEN WINDS TONIGHT INTO TUESDAY
MORNING ACROSS THE PLAINS. ADDED A HIGH WIND WARNING FROM MIDNIGHT
THROUGH TUESDAY MORNING FOR DOWNSLOPE AREAS OFF THE PALMER
DIVIDE...GENERALLY AREAS NORTH OF HIGHWAY 50 ON THE PLAINS. THE
LATEST HIGH-RES MODEL GUIDANCE SUGGESTS NORTH WINDS GUSTING IN
EXCESS OF 65 MPH ARE POSSIBLE. THIS WILL COMBINE WITH SNOW TO
PRODUCE VERY DANGEROUS TRAVEL CONDITIONS ACROSS THE PLAINS.
REDUCED VISIBILITIES AND VERY STRONG CROSS WINDS ON EAST WEST
HIGHWAYS.
ALSO CANCELED THE TORNADO WATCH FOR THE FAR EASTERN PLAINS.
THUNDERSTORMS HAVE MOVED OFF INTO WESTERN KANSAS AT THIS TIME.
THERE COULD BE A COUPLE OF WEAKER THUNDERSTORMS OVER BACA AND
PROWERS COUNTIES THROUGH 9 PM...BUT SHOULD NOT BECOME STRONG OR
SEVERE.
OTHERWISE...SNOW AMOUNTS AND LOCATIONS APPEAR TO BE OK AT THIS
TIME BASED ON THE LATEST GUIDANCE WITH LITTLE CHANGE THERE. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 330 PM MST MON NOV 16 2015
...MAJOR WINTER STORM TO AFFECT THE REGION THROUGH TUESDAY...
CURRENTLY...
700 MB CIRCULATION LIKELY OVER THE PIKES PEAK REGION AT 2 PM AS PER
RADAR AND HRRR GUIDANCE. SNOW IS FALLING ACROSS THE HIGHER
ELEVATIONS OF THE PIKES PEAK REGION ALONG WITH STRONGER STORMS NOTED
OVER THE PLAINS. 500 MB CIRCULATION WAS JUST SW OF THE 4 CORNERS AS
PER WATER VAPOR. NICE BAROCLINIC LEAF DEVELOPING IN THE STRONG
DIVERGENT REGION OVER WESTERN AND CENTRAL COLORADO. A WIND SHIFT
LINE WAS NOTED ON RADAR MOVING ACROSS THE PUEBLO/EL PASO COUNTY
LINE...MOVING SOUTH.
THIS EVENING THROUGH TONIGHT...
CONDITIONS WILL CONTINUE TO DETERIORATE ACROSS THE PALMER DIVIDE
THIS AFTERNOON AND EVENING AND BLIZZARD CONDITIONS WILL LIKELY
DEVELOP BY 7 TO 8 PM AS 700 MB WIND STEADILY INCREASE. HRRR BY
MIDNIGHT SHOWS 700 MB WINDS OF 70 KNTS OVER N EL PASO COUNTY. HEAVY
WIND DRIVEN SNOW WILL CONTINUE THROUGH TONIGHT AND LAST INTO
TOMORROW MORNING. WELL OVER A FOOT OF SNOW IS LIKELY AND GUSTS TO 50
MPH ARE LIKELY. SNOW DRIFTS WILL BE SIGNIFICANT AND TRAVEL WILL BE
DIFFICULT IF NOT IMPOSSIBLE ACROSS THE PALMER DVD.
LATEST GUIDANCE SHOWS THE 700 MB CIRCULATION MOVING EAST-SOUTHEAST
THIS EVENING...AND THIS WILL LIKELY FAVOR ANOTHER AREA OF HEAVY SNOW
OVER THE HIGHER ELEVATIONS OF EASTERN LAS ANIMAS COUNTY. FOR THIS
REASON I HAVE ISSUED A WINTER STORM WARNING FOR EASTER LAS ANIMAS
COUNTY. TOTAL ACCUMS THIS REGION SHOULD BE ABOUT 10 INCHES.
LOCALLY HEAVY SNOW WILL ALSO FALL ALONG THE EAST FACING SLOPES OF
THE S MTNS...BUT WITH 700 MB WINDS HAVING A MORE NORTHERLY COMPONENT
(VS NORTHEASTERLY)...EXCESSIVELY HEAVY SNOW IS NOT ANTICIPATED.
OVERALL 6 TO 10 INCHES IS LIKELY WITH HIGHER AMOUNTS AT MTN TOP.
ALONG THE LOWER ARK RVR VALLEY FROM FREMONT TO THE KS BORDER SHOULD
SEE THE LEAST AMOUNT OF SNOW AS STRONG DOWNSLOPE FLOW WILL LIMIT
ACCUMS THIS REGION. HOWEVER...WITH STRONG WINDS...HAVE INCLUDED MOST
OF THESE REGIONS IN A SNOW AND BLOWING SNOW ADVISORY. THE SNOW OVER
THE LOWER ELEVATIONS OF THE E PLAINS SHOULD BEGIN LATE THIS EVENING
AS COLDER AIR MOVES INTO THE REGION.
STRONG WINDS WILL BE AN ISSUE WITH THIS STORM TONIGHT ACROSS ALL OF
THE PLAINS WITH GUSTS TO 50 MPH WIDESPREAD. STRONGER GUSTS WILL BE
POSSIBLE.
ACROSS THE INTERIOR MTNS...AS THE 500 MB LOW MOVES EAST...FLOW WILL
BECOME LESS FAVORABLE FOR THE SW MTNS...AND SNOW RATES SHOULD
RAPIDLY DECREASE THIS REGION.
TUESDAY...
STORM WILL MOVE SLOWLY EAST. MAIN CONCERN IS HOW MUCH SNOW WILL FALL
OVER THE FAR EASTERN PLAINS. CONFIDENCE IS HIGH THAT E LAS ANIMAS
WILL SEE HEAVY SNOW BUT AREAS FROM LAMAR AND SPRINGFIELD I AM NOT SO
CONFIDENT AS STORM WILL BE LIFTING OUT AND TEMPS WILL NOT BE ALL
THAT COLD. HOWEVER...IF EC VERIFIES WITH A MORE SOUTHERN TRACK THIS
WILL PUT THE FAR EASTERN COUNTIES IN A BETTER CHANCE OF SNOW. WILL
DISCUSS THIS CONCERN WITH THE EVENING SHIFT AND ALLOW THEM TO ADJUST
THE FCST AS NEEDED.
BLIZZARD CONDITIONS OVER THE PALMER DIVIDE REGION SHOULD BE
LESSENING BY LATE MORNING INTO EARLY AFTERNOON. WINDS WILL STILL BE
AN ISSUE AND BLOWING SNOW WILL LIKELY CONTINUE THROUGH THE DAY. I
WOULD NOT BE TOO SURPRISED IF WE SEE SOME SUN ACROSS THE I-25
CORRIDOR LATE IN THE DAY.
STRONG WINDS WILL BE A CONCERN OVER ALL OF THE PLAINS TUESDAY AND
GUSTS OVER 50 MPH ARE LIKELY ALL AREAS. THE WINDS WILL SLOWLY
DECREASE WEST TO EAST DURING THE AFTERNOON. /HODANISH
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 330 PM MST MON NOV 16 2015
WILL KEEP DISCUSSION BRIEF DUE TO ONGOING ACTIVE METEOROLOGICAL
PATTERN. PRIMARILY LONGER TERM ISSUES INCLUDES TIMING OF
DEPARTING SNOW CURRENTLY IMPACTING FORECAST DISTRICT
...TEMPERATURES AND WINDS.
RECENT LONGER TERM PV ANALYSIS...FORECAST MODEL SOUNDINGS AND
COMPUTER SIMULATIONS INDICATE THAT VIGOROUS CLOSED UPPER LOW
LOCATED OVER FAR SOUTHEASTERN COLORADO AT 12Z TUESDAY WILL SHIFT
INTO EASTERN KANSAS BY TUESDAY EVENING AND THEN MOVE INTO IOWA BY
NOON WEDNESDAY.
HAVE DEPICTED CONTINUED GUSTY TO STRONG WINDS AND PRECIPITATION
INTO TUESDAY EVENING(PRIMARILY EASTERN SECTIONS) WITH
PRECIPITATION ENDING OVER MAJORITY OF THE FORECAST DISTRICT BY
12Z WEDNESDAY.
THEN A RETURN TO BASICALLY TRANQUIL METEOROLOGICAL CONDITIONS(OUTSIDE
OF THE CENTRAL MOUNTAINS...WHERE SOME SNOW WILL BE POSSIBLE AT
TIMES) SHOULD BE NOTED OVER THE FORECAST DISTRICT FROM WEDNESDAY
INTO NEXT MONDAY AS NORTHWESTERLY TO ZONAL UPPER FLOW DEVELOPS
OVER SOUTHERN COLORADO.
OVERALL...TEMPERATURES RUNNING WITHIN A CATEGORY OR SO OF
MID TO LATE NOVEMBER CLIMATOLOGICAL AVERAGES ARE ANTICIPATED
DURING THE LONGER TERM WITH WARMEST TEMPERATURES EXPECTED SUNDAY
AND NEXT MONDAY...WHILE COOLEST CONDITIONS SHOULD BE EXPERIENCED
SATURDAY. FINALLY...MOST AGGRESSIVE GRADIENT WINDS DURING THE
LONGER TERM ARE PROJECTED FROM TUESDAY EVENING INTO WEDNESDAY
NIGHT AND THEN AGAIN FROM FRIDAY INTO FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1013 PM MST MON NOV 16 2015
KALS...SNOW WILL PRODUCE IFR TO LIFR CONDITIONS THROUGH AROUND 10Z
THIS MORNING WITH IMPROVING CONDITIONS THROUGH THE LATE MORNING TO
AFTERNOON. NORTHWEST WINDS WILL BE GUSTY TO NEAR 30 KTS DURING THE
MORNING AND EARLY AFTERNOON HOURS.
KCOS AND KPUB...SNOW IS FILLING IN ACROSS KCOS AND SOUTH OF KPUB.
EXPECT IFR CONDITIONS WITH SNOW AT KCOS THROUGH MUCH OF THE NIGHT
INTO TUESDAY MORNING. IN ADDITION...VERY STRONG NORTHERLY WINDS
ARE EXPECTED OVERNIGHT WITH BLOWING SNOW AN ISSUE. SEVERAL INCHES
OF SNOWFALL ARE POSSIBLE ON AREA RUNWAYS BY TUESDAY MORNING. FOR
KPUB...DOWNSLOPE EFFECTS WILL LIKELY KEEP MOST SNOW OUT OF KPUB
BUT IT CANNOT BE RULED OUT THROUGH TUESDAY MORNING. IF SNOW CAN
MOVE OVER KPUB...REDUCED CIGS AND VIS ARE EXPECTED DUE TO SNOW AND
BLOWING SNOW. EXTREMELY STRONG WINDS GUSTING TO NEAR 50 KTS ARE
POSSIBLE AT KPUB. BOTH SITES WILL SEE IMPROVEMENTS BY LATE MORNING
TO EARLY AFTERNOON. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 AM TO 8 PM MST TUESDAY FOR COZ098-
099.
HIGH WIND WARNING UNTIL 11 AM MST TUESDAY FOR COZ085-086-089-093-
095-097.
WINTER WEATHER ADVISORY UNTIL 5 PM MST TUESDAY FOR COZ089-093.
WINTER WEATHER ADVISORY UNTIL 8 AM MST TUESDAY FOR COZ059-061-
063-072-076-079-080.
WINTER WEATHER ADVISORY UNTIL 5 AM MST TUESDAY FOR COZ065-067-
069>071-078-086.
WINTER WEATHER ADVISORY UNTIL 8 PM MST TUESDAY FOR COZ095>097.
WINTER STORM WARNING UNTIL 8 AM MST TUESDAY FOR COZ058-060-073.
WINTER STORM WARNING UNTIL 11 AM MST TUESDAY FOR COZ074-075-081-
082-087-088.
WINTER STORM WARNING UNTIL 5 PM MST TUESDAY FOR COZ094.
WINTER WEATHER ADVISORY UNTIL 11 AM MST TUESDAY FOR COZ085.
WINTER STORM WARNING UNTIL 5 AM MST TUESDAY FOR COZ066-068.
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR COZ064.
BLIZZARD WARNING UNTIL 11 AM MST TUESDAY FOR COZ084.
&&
$$
UPDATE...KT
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS PUEBLO CO
914 PM MST MON NOV 16 2015
.UPDATE...
ISSUED AT 903 PM MST MON NOV 16 2015
MODELS ARE TRENDING SLIGHTLY SOUTHWARD AND SLOWER WITH THE TRACK
OF THE UPPER LOW ACROSS NEW MEXICO INTO THE TX/OK PANHANDLES BY
12Z TUES. GETTING A BIT OF A BREAK ACROSS THE I-25 CORRIDOR...BUT
AS UPPER LOW SKIRTS TO OUR SOUTH...THIS SHOULD FILL IN AGAIN AS
INTENSE TROWAL WRAPS UP AND SPREADS EASTWARD AROUND NORTHWEST SIDE
OF THE UPPER LOW. DID A MAJOR OVERHALL TO HEADLINES...BRINGING
MORE OF THE RATON MESA REGION AND SOUTHERN I-25 CORRIDOR
WALSENBURG TO TRINIDAD TO A WINTER STORM WARNING. INITIAL WARM
START...AND SLOW COOL DOWN ACROSS THE PLAINS IS MAKING WINTER
WEATHER HIGHLIGHT DECISIONS DIFFICULT. EXTENSIVE WIND AND A PERIOD
OF HEAVY SNOW IS EXPECTED TUESDAY MORNING...BUT WARM GROUND MAY
PREVENT A LOT OF LIFTING OF THE FRESH SNOW LIMITING POOR
VISIBILITIES TO DIRECTLY UNDER THE HEAVIER SNOW BANDS. HOWEVER
CONDITIONS ACROSS THE EASTERN COUNTIES...RUNNING FROM
KIOWA...PROWERS...BENT...SOUTHERN OTERO AND NORTHWEST BACA
COUNTIES WILL HAVE TO BE WATCHED CLOSELY...AS IT COULD BE VERY
NEAR WHITE OUT CONDITIONS AT TIMES IF TEMPERATURES CAN STAY COLD
ENOUGH ON TUESDAY. FOR NOW...HAVE SPREAD THE WINTER WEATHER
ADVISORIES OUT TO ALL OF SOUTHEAST COLORADO PLAINS. LATER SHIFTS
WILL HAVE TO MONITOR LOCATIONS UNDER THE TROWAL OUT THAT WAY FOR
POSSIBLE UPGRADE TO A WARNING AT A LATER POINT. THESE AREAS LOOK
TO GET HIT HARDEST STARTING TUESDAY MORNING. -KT
UPDATE ISSUED AT 540 PM MST MON NOV 16 2015
THE MAIN UPDATE HAS BEEN TO STRENGTHEN WINDS TONIGHT INTO TUESDAY
MORNING ACROSS THE PLAINS. ADDED A HIGH WIND WARNING FROM MIDNIGHT
THROUGH TUESDAY MORNING FOR DOWNSLOPE AREAS OFF THE PALMER
DIVIDE...GENERALLY AREAS NORTH OF HIGHWAY 50 ON THE PLAINS. THE
LATEST HIGH-RES MODEL GUIDANCE SUGGESTS NORTH WINDS GUSTING IN
EXCESS OF 65 MPH ARE POSSIBLE. THIS WILL COMBINE WITH SNOW TO
PRODUCE VERY DANGEROUS TRAVEL CONDITIONS ACROSS THE PLAINS.
REDUCED VISIBILITIES AND VERY STRONG CROSS WINDS ON EAST WEST
HIGHWAYS.
ALSO CANCELED THE TORNADO WATCH FOR THE FAR EASTERN PLAINS.
THUNDERSTORMS HAVE MOVED OFF INTO WESTERN KANSAS AT THIS TIME.
THERE COULD BE A COUPLE OF WEAKER THUNDERSTORMS OVER BACA AND
PROWERS COUNTIES THROUGH 9 PM...BUT SHOULD NOT BECOME STRONG OR
SEVERE.
OTHERWISE...SNOW AMOUNTS AND LOCATIONS APPEAR TO BE OK AT THIS
TIME BASED ON THE LATEST GUIDANCE WITH LITTLE CHANGE THERE. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 330 PM MST MON NOV 16 2015
...MAJOR WINTER STORM TO AFFECT THE REGION THROUGH TUESDAY...
CURRENTLY...
700 MB CIRCULATION LIKELY OVER THE PIKES PEAK REGION AT 2 PM AS PER
RADAR AND HRRR GUIDANCE. SNOW IS FALLING ACROSS THE HIGHER
ELEVATIONS OF THE PIKES PEAK REGION ALONG WITH STRONGER STORMS NOTED
OVER THE PLAINS. 500 MB CIRCULATION WAS JUST SW OF THE 4 CORNERS AS
PER WATER VAPOR. NICE BAROCLINIC LEAF DEVELOPING IN THE STRONG
DIVERGENT REGION OVER WESTERN AND CENTRAL COLORADO. A WIND SHIFT
LINE WAS NOTED ON RADAR MOVING ACROSS THE PUEBLO/EL PASO COUNTY
LINE...MOVING SOUTH.
THIS EVENING THROUGH TONIGHT...
CONDITIONS WILL CONTINUE TO DETERIORATE ACROSS THE PALMER DIVIDE
THIS AFTERNOON AND EVENING AND BLIZZARD CONDITIONS WILL LIKELY
DEVELOP BY 7 TO 8 PM AS 700 MB WIND STEADILY INCREASE. HRRR BY
MIDNIGHT SHOWS 700 MB WINDS OF 70 KNTS OVER N EL PASO COUNTY. HEAVY
WIND DRIVEN SNOW WILL CONTINUE THROUGH TONIGHT AND LAST INTO
TOMORROW MORNING. WELL OVER A FOOT OF SNOW IS LIKELY AND GUSTS TO 50
MPH ARE LIKELY. SNOW DRIFTS WILL BE SIGNIFICANT AND TRAVEL WILL BE
DIFFICULT IF NOT IMPOSSIBLE ACROSS THE PALMER DVD.
LATEST GUIDANCE SHOWS THE 700 MB CIRCULATION MOVING EAST-SOUTHEAST
THIS EVENING...AND THIS WILL LIKELY FAVOR ANOTHER AREA OF HEAVY SNOW
OVER THE HIGHER ELEVATIONS OF EASTERN LAS ANIMAS COUNTY. FOR THIS
REASON I HAVE ISSUED A WINTER STORM WARNING FOR EASTER LAS ANIMAS
COUNTY. TOTAL ACCUMS THIS REGION SHOULD BE ABOUT 10 INCHES.
LOCALLY HEAVY SNOW WILL ALSO FALL ALONG THE EAST FACING SLOPES OF
THE S MTNS...BUT WITH 700 MB WINDS HAVING A MORE NORTHERLY COMPONENT
(VS NORTHEASTERLY)...EXCESSIVELY HEAVY SNOW IS NOT ANTICIPATED.
OVERALL 6 TO 10 INCHES IS LIKELY WITH HIGHER AMOUNTS AT MTN TOP.
ALONG THE LOWER ARK RVR VALLEY FROM FREMONT TO THE KS BORDER SHOULD
SEE THE LEAST AMOUNT OF SNOW AS STRONG DOWNSLOPE FLOW WILL LIMIT
ACCUMS THIS REGION. HOWEVER...WITH STRONG WINDS...HAVE INCLUDED MOST
OF THESE REGIONS IN A SNOW AND BLOWING SNOW ADVISORY. THE SNOW OVER
THE LOWER ELEVATIONS OF THE E PLAINS SHOULD BEGIN LATE THIS EVENING
AS COLDER AIR MOVES INTO THE REGION.
STRONG WINDS WILL BE AN ISSUE WITH THIS STORM TONIGHT ACROSS ALL OF
THE PLAINS WITH GUSTS TO 50 MPH WIDESPREAD. STRONGER GUSTS WILL BE
POSSIBLE.
ACROSS THE INTERIOR MTNS...AS THE 500 MB LOW MOVES EAST...FLOW WILL
BECOME LESS FAVORABLE FOR THE SW MTNS...AND SNOW RATES SHOULD
RAPIDLY DECREASE THIS REGION.
TUESDAY...
STORM WILL MOVE SLOWLY EAST. MAIN CONCERN IS HOW MUCH SNOW WILL FALL
OVER THE FAR EASTERN PLAINS. CONFIDENCE IS HIGH THAT E LAS ANIMAS
WILL SEE HEAVY SNOW BUT AREAS FROM LAMAR AND SPRINGFIELD I AM NOT SO
CONFIDENT AS STORM WILL BE LIFTING OUT AND TEMPS WILL NOT BE ALL
THAT COLD. HOWEVER...IF EC VERIFIES WITH A MORE SOUTHERN TRACK THIS
WILL PUT THE FAR EASTERN COUNTIES IN A BETTER CHANCE OF SNOW. WILL
DISCUSS THIS CONCERN WITH THE EVENING SHIFT AND ALLOW THEM TO ADJUST
THE FCST AS NEEDED.
BLIZZARD CONDITIONS OVER THE PALMER DIVIDE REGION SHOULD BE
LESSENING BY LATE MORNING INTO EARLY AFTERNOON. WINDS WILL STILL BE
AN ISSUE AND BLOWING SNOW WILL LIKELY CONTINUE THROUGH THE DAY. I
WOULD NOT BE TOO SURPRISED IF WE SEE SOME SUN ACROSS THE I-25
CORRIDOR LATE IN THE DAY.
STRONG WINDS WILL BE A CONCERN OVER ALL OF THE PLAINS TUESDAY AND
GUSTS OVER 50 MPH ARE LIKELY ALL AREAS. THE WINDS WILL SLOWLY
DECREASE WEST TO EAST DURING THE AFTERNOON. /HODANISH
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 330 PM MST MON NOV 16 2015
WILL KEEP DISCUSSION BRIEF DUE TO ONGOING ACTIVE METEOROLOGICAL
PATTERN. PRIMARILY LONGER TERM ISSUES INCLUDES TIMING OF
DEPARTING SNOW CURRENTLY IMPACTING FORECAST DISTRICT
...TEMPERATURES AND WINDS.
RECENT LONGER TERM PV ANALYSIS...FORECAST MODEL SOUNDINGS AND
COMPUTER SIMULATIONS INDICATE THAT VIGOROUS CLOSED UPPER LOW
LOCATED OVER FAR SOUTHEASTERN COLORADO AT 12Z TUESDAY WILL SHIFT
INTO EASTERN KANSAS BY TUESDAY EVENING AND THEN MOVE INTO IOWA BY
NOON WEDNESDAY.
HAVE DEPICTED CONTINUED GUSTY TO STRONG WINDS AND PRECIPITATION
INTO TUESDAY EVENING(PRIMARILY EASTERN SECTIONS) WITH
PRECIPITATION ENDING OVER MAJORITY OF THE FORECAST DISTRICT BY
12Z WEDNESDAY.
THEN A RETURN TO BASICALLY TRANQUIL METEOROLOGICAL CONDITIONS(OUTSIDE
OF THE CENTRAL MOUNTAINS...WHERE SOME SNOW WILL BE POSSIBLE AT
TIMES) SHOULD BE NOTED OVER THE FORECAST DISTRICT FROM WEDNESDAY
INTO NEXT MONDAY AS NORTHWESTERLY TO ZONAL UPPER FLOW DEVELOPS
OVER SOUTHERN COLORADO.
OVERALL...TEMPERATURES RUNNING WITHIN A CATEGORY OR SO OF
MID TO LATE NOVEMBER CLIMATOLOGICAL AVERAGES ARE ANTICIPATED
DURING THE LONGER TERM WITH WARMEST TEMPERATURES EXPECTED SUNDAY
AND NEXT MONDAY...WHILE COOLEST CONDITIONS SHOULD BE EXPERIENCED
SATURDAY. FINALLY...MOST AGGRESSIVE GRADIENT WINDS DURING THE
LONGER TERM ARE PROJECTED FROM TUESDAY EVENING INTO WEDNESDAY
NIGHT AND THEN AGAIN FROM FRIDAY INTO FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 330 PM MST MON NOV 16 2015
EXTREME NORTH WINDS WILL BE THE MAIN CONCERN AT KCOS AND KPUB DURING
THE NEXT 24. PEAK WINDS GUSTING OVER 50 KNOTS ARE NOT OUT OF THE
QUESTION. SNOW WILL BE POSSIBLE AT KCOS...BUT THE GRADIENT OF
SNOWFALL OVER THE COLORADO SPRINGS REGION WILL BE QUITE HIGH...WITH
VERY HIGH AMOUNTS N OF THE AIRPORT AND MUCH LESSER AMOUNTS S OF THE
AIRPORT. OVERALL WE ARE EXPECTING ABOUT 5-6 INCHES AT KCOS...BUT
THIS IS OUR BEST SCIENTIFIC GUESS.
KPUB MAY ALSO SEE SOME PRECIP....ESPECIALLY THIS EVENING. DOWNSLOPE
FLOW OVER KPUB SHOULD SIGNIFICANTLY DECREASE ANY SNOWFALL AT KPUB.
STRONG WINDS WILL BE A MAJOR ISSUE AT KPUB THROUGH THE NEXT 24H.
GUSTY N WINDS WILL ALSO BE A CONCERN AT KALS...BUT WINDS SHOULD NOT
BE AS STRONG. SOME SNOW SHOWERS WILL ALSO BE POSSIBLE AT KALS THIS
EVENING.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 5 AM TO 8 PM MST TUESDAY FOR COZ098-
099.
HIGH WIND WARNING UNTIL 11 AM MST TUESDAY FOR COZ085-086-089-093-
095-097.
WINTER WEATHER ADVISORY UNTIL 5 PM MST TUESDAY FOR COZ089-093.
WINTER WEATHER ADVISORY UNTIL 8 AM MST TUESDAY FOR COZ059-061-
063-072-076-079-080.
WINTER WEATHER ADVISORY UNTIL 5 AM MST TUESDAY FOR COZ065-067-
069>071-078-086.
WINTER WEATHER ADVISORY UNTIL 8 PM MST TUESDAY FOR COZ095>097.
WINTER STORM WARNING UNTIL 8 AM MST TUESDAY FOR COZ058-060-073.
WINTER STORM WARNING UNTIL 11 AM MST TUESDAY FOR COZ074-075-081-
082-087-088.
WINTER STORM WARNING UNTIL 5 PM MST TUESDAY FOR COZ094.
WINTER WEATHER ADVISORY UNTIL 11 AM MST TUESDAY FOR COZ085.
WINTER STORM WARNING UNTIL 5 AM MST TUESDAY FOR COZ066-068.
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR COZ064.
BLIZZARD WARNING UNTIL 11 AM MST TUESDAY FOR COZ084.
&&
$$
UPDATE...KT
AREA FORECAST DISCUSSION
NWS ALBANY NY
1000 PM EST WED NOV 18 2015
.SYNOPSIS...
A WARM FRONT WILL WORK ACROSS OUR REGION TONIGHT...KEEPING
TEMPERATURES MILD UNDER A CANOPY OF INCREASING CLOUDS. SPOTTY
DRIZZLE WILL BREAK OUT EARLY THURSDAY...FOLLOWED BY HEAVIER
SHOWERS LATER IN THE DAY WHICH WILL BE AHEAD OF A COLD FRONT THAT
WILL CROSS OUR REGION THURSDAY NIGHT. COOLER DRIER AIR WILL FOLLOW
FOR FRIDAY... FOLLOWED BY EVEN COLDER AIR AND SOME SHOWERS OF RAIN
OR SNOW FOR LATER IN THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 930 PM EST...LOWER CLOUDS HAVE OVERSPREAD THE ENTIRE REGION.
TEMEPRATURES REMAINED MILD...BETWEEN THE MID 40S AND LOWER 50S
MOST PLACES...AND UPPER 30S TO LOWER 40S OVER EXTREME EASTERN
BERKSHIRE COUNTY AND WINDHAM COUNTY. AREAS OF DRIZZLE ARE NOW
NOTED ON RADAR OVER THE EASTERN CATSKILLS AND HAVE REVISED THE
WEATHER GRIDS TO INCLUDE AREAS OF DRIZZLE.
A SOUTH TO SOUTHEAST BREEZE AVERAGED 10-15 MPH...WITH SOME GUSTS TO
20 MPH OR A LITTLE HIGHER.
PREVIOUS DISCUSSION...
EVEN FURTHER SOUTH ACROSS THE MID ATLANTIC...TEMPERATURES WERE IN
THE 60S WITH DEWPOINTS SURGING THROUGH THE 40S. THE LEADING EDGE OF
THIS MILDER AND MORE MOIST AIR MASS WAS PRODUCING THE STRATUS
WHICH CONTINUED TO SPREAD NORTH AND WAS NOW COVERING ALL BUT THE
NORTHERNMOST AREAS. THESE CLOUDS...ADDITIONAL WARM AIR ADVECTION
AND A PERSISTENT BREEZE SHOULD KEEP TEMPERATURES FROM FALLING MUCH
AT ALL. THEREFORE...WE WENT A BIT HIGHER THAN ALL MACHINE GUIDANCE
REGARDING OVERNIGHT LOWS.
LOWS WILL BE IN THE 40S...UPPER 40S LOCALLY IN THE CAPITAL REGION.
AS THE MOISTURE DEEPENS OVERNIGHT THERE MIGHT BE A LITTLE SPOTTY DRIZZLE...
MAINLY ACROSS OUR CATSKILLS DUE TO UPSLOPE BUT EVEN THE MID HUDSON VALLEY
LITCHFIELD AND THE SOUTHERN BERKSHIRES COULD SEE SOME SPOTTY DRIZZLE BY
MIDNIGHT. BY DAYBREAK...EVERYONE COULD SEE A LITTLE SPOTTY DRIZZLE OR A LIGHT
SHOWER ON AN ISOLATED BASIS.
THE SOUTH TO SOUTHEAST BREEZE WILL AVERAGE 5-15 MPH TONIGHT...WITH SOME
HIGHER GUSTS...ESPECIALLY ACROSS THE HIGHER TERRAIN.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
BY THURSDAY...OUR WHOLE AREA WILL BE IN A MOIST MILD AIR MASS
WITH A COLD FRONT RAPIDLY APPROACHING FROM THE WEST.
THIS IS THE SAME SYSTEM THAT PRODUCED QUITE AN ARRAY OF FOUL WEATHER
OUT WEST...INCLUDING SEVERE WEATHER AND EVEN BLIZZARD CONDITIONS.
NEITHER IS EXPECTED FOR US (INSTABILITY NOT THERE FOR ANY REAL
CONVECTION). A RUMBLE OF THUNDER IS CERTAINLY POSSIBLE BUT WITH
SHOWALTER VALUES >0 AND CAPE VALUES NEAR 0 J/KG WILL KEEP
ANY MENTION OF THUNDERSTORMS OUT OF THE GRIDS FOR NOW.
THAT SAID...WITH PWATS SOARING PAST AN INCH....TWO STANDARDS ABOVE
NORMAL. THE COMBINATION OF THIS MOISTURE...THE FRONT...SHORTWAVE
ENERGY AND OUR AREA COMING UNDER THE DIVERGENT AREA OF THE RR 100KT
NIGHT BY EVENING...ALL POINT TO ROUND OF SHOWERS...SOME CONTAINING
MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL.
WHAT IS A LITTLE DIFFERENT FROM PREVIOUS RUNS...THERE IS LESS OF TENDENCY FOR
A SECONDARY WAVE TO DEVELOP ALONG THE TRIPLE POINT...AS THERE WAS
IN SOME EARLIER RUNS. IT LOOKS LIKE A PROGRESSIVE SYSTEM...PRETTY MUCH
WHAT WE HAVE SEEN THIS AUTUMN.
A GUSTY SOUTH WIND WILL ENSUE ON THURSDAY...10-15 MPH...WITH GUSTS
25-35 MPH ACROSS PORTIONS OF THE HIGHER TERRAIN...AND EVEN
SOME SECTIONS OF THE CAPITAL REGION AND MOHAWK VALLEY. DURING
HEAVY SHOWERS...IT IS REMOTELY POSSIBLE THAT SOME GUSTS COULD EVEN
REACH A LITTLE HIGHER THAN THAN THAT...BUT JUST BRIEFLY.
THEREFORE...NO WIND HEADLINES WERE ASSIGNED WITH THIS PACKAGE.
THE ACTUAL COLD FRONT LOOKS TO MOVE ON THROUGH THURSDAY EVENING...
FOLLOWED BY HIGH PRESSURE BEGINNING TO BUILD IN BY EARLY FRIDAY.
IN FACT...THE SKY MIGHT ACTUALLY CLEAR BY DAYBREAK FRIDAY OR AT
LEAST PARTIALLY CLEAR.
BASED ON UPSTREAM TEMPERATURES WELL INTO THE 60S...WE WILL GO SLIGHTLY
HIGHER THAN ALL MACHINE GUIDANCE ON THURSDAY. LOOK FOR HIGHS LOWER TO MID
60S IN THE VALLEYS...MID OR UPPER 50S EVEN ACROSS THE HIGHER TERRAIN.
TURNING COOLER...BUT STILL ABOVE NORMAL THURSDAY NIGHT WITH LOWS
RANGING FROM THE UPPER 30S TO MID 40S.
FRIDAY SHOULD FEATURE AT LEAST PARTIAL SUNSHINE AS THE FLOW LOOKS TOO ANTI-
CYCLONIC FOR MUCH LAKE INDUCED CLOUDS (OUTSIDE OF THE ADIRONDACKS WHERE
UPSLOPE CLOUDS AND A FEW SHOWERS OF RAIN OR RAIN AND WET SNOW MIXED ARE
POSSIBLE).
HIGH TEMPERATURES WILL BE NOTICEABLY COOLER THAN THURSDAY...HIGHS NEAR 50
IN THE VALLEYS...LOWER TO MID 40S HIGHER TERRAIN...CLOSER TO 40
ACROSS THE ADIRONDACKS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE EXTENDED OPENS WITH A POTENT UPPER LEVEL TROUGH APPROACHING FROM
THE GREAT LAKES REGION AND THE MIDWEST. THE UPPER LEVEL TROUGH
TURNS NEGATIVELY TILTED ACCORDING TO LATEST GFS/ECMWF...AS THE SFC
CYCLONE LIFTS NORTHEAST ACROSS THE ERN GREAT LAKES REGION INTO SE
ONTARIO BY 12Z SUN. THERE IS ENOUGH MOISTURE WITH THE OCCLUDED
FRONT TO THE SYSTEM FOR A PERIOD OF RAIN SHOWERS TRANSITIONING TO
SNOW SHOWERS. THERE IS DECENT LIFT AND CONVERGENCE WITH THE
BOUNDARY. SOME LIGHT SNOW ACCUMULATIONS ARE POSSIBLE WITH A COATING
TO LESS THAN A HALF AN INCH IN THE VALLEY AREAS...AND AN INCH OR TWO
OVER THE HIGHER TERRAIN. THE LIGHT SNOW IS SUPPORTED FROM SOME OF
THE ENSEMBLES. THE LATEST GEFS PLUME DIAGRAM YIELDS ABOUT A TENTH OF
AN INCH OF SNOWFALL FOR ALBANY WITH PERHAPS A HALF DOZEN MEMBERS OR
SO. LOWS SAT NIGHT WILL RANGE FROM THE MID AND U20S OVER THE MTNS TO
U20S TO L30S OVER THE VALLEYS.
SUNDAY WILL BE A BLUSTERY AND COLD DAY WITH THE LONG-WAVE TROUGH
AXIS APPROACHING THE REGION. A SECONDARY COLD FRONT OR SFC TROUGH
WILL MOVE THROUGH WITH H850 TEMPS FALL TO -7C TO -10C. SOME SCT
SNOW AND RAIN SHOWERS ARE POSSIBLE. THE RAIN SHOWERS WILL BE MAINLY
WHERE THE BOUNDARY LAYER WARMS ENOUGH WITH TEMPS IN THEN 40-45F
RANGE. THE HIGHER POPS WILL BE NORTH AND WEST OF THE CAPITAL
DISTRICT AND THE MOHAWK RIVER VALLEY. SOME ADDITIONAL LIGHT SNOW
ACCUMS ARE POSSIBLE OVER THE WRN DACKS...ERN CATSKILLS...AND SRN
GREENS. HIGHS WILL BE MAINLY IN THE U30S TO L40S IN THE
VALLEYS...AND LOWER TO U30S OVER THE HIGHER TERRAIN...EXCEPT SOME
U20S IN THE SRN DACKS.
SUNDAY NIGHT INTO MONDAY...A COLD AIR MASS BUILDS IN FROM THE OHIO
VALLEY WITH SOME LAKE EFFECT SNOWFALL POSSIBLE BASED ON THE MEDIUM
RANGE GUIDANCE. LOCATIONS IN THE WRN DACKS...AND W-CNTRL MOHAWK
VALLEY MAY GET AT LEAST SOME LIGHT SNOW ACCUMS. THE REST OF THE FCST
AREA WILL REMAIN DRY...BUT COLD. THE LATEST GFS H850 TEMPS FALL TO
-10C TO -13C OVER THE FCST AREA. LOWS WILL BE IN THE MID AND U20S IN
THE VALLEYS...AND TEENS TO L20S OVER THE MTNS. HIGHS ON MONDAY
RANGE FROM THE U30S TO L40S IN THE VALLEY AREAS...AND U20S TO M30S
OVER THE MTNS.
MONDAY NIGHT INTO TUESDAY...THE LAKE EFFECT SNOWFALL SHOULD
TAPER...AS THE FLOW BECOMES MORE ZONAL. A WEAK DISTURBANCE IN THE
ZONAL FLOW COULD BRING A SLIGHT CHC OF SHOWERS TUE AFTERNOON WEST OF
THE MOHAWK VALLEY. THE ECMWF REMAINS DRY. TEMPS MODERATE TO
SEASONAL VALUES ON TUESDAY WITH SOME MID AND U40S IN THE CAPITAL
DISTRICT...TACONICS...MID HUDSON VALLEY...AND NW CT. U30S TO L40S
ARE COMMON NORTH AND WEST.
TUESDAY NIGHT INTO WEDNESDAY...HIGH PRESSURE WILL RIDGE BACK IN OVER
THE NORTHEAST WITH FAIR AND DRY WEATHER FOR THE MID WEEK...AND
SEASONABLE TEMPS.
OVERALL...TEMPS WILL AVERAGE NEAR NORMAL WITH PCPN BELOW NORMAL IN
THE LONG TERM.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
MVFR CIGS ALREADY OCCURRING AT KPOU/KPSF...AND EXPECT MVFR CIGS TO
MOVE INTO KALB ND KGFL BEFORE MIDNIGHT. THEN MVFR CIGS AND
POSSIBLE MVFR VSBYS WILL OCCUR FOR THE REST OF THE NIGHT AS SOME
FOG OR DRIZZLE DEVELOPS ACROSS THE REGION. IFR CIGS ARE ALSO
POSSIBLE AT KPOU/KPSF LATE TONIGHT...ESPECIALLY AT KPSF WHERE THE
IFR CIGS COULD START AROUND 06Z.
MVFR/IFR CIGS WILL PERSIST INTO THE MORNING...BUT THE DRIZZLE AND
FOG WILL GIVE WAY TO MORE SHOWERY PCPN AS THE COLD FRONT
APPROACHES FROM THE WEST. EXPECT THE WIDESPREAD SHOWERS TO BEGINN
AROUND 15Z/16Z...WITH IFR CIGS AND MVFR VSBYS OCCURING AT ALL THE
TAF SITES THROUGH THE REST OF THE TAF PERIOD ENDING AT 00Z FRIDAY.
A SOUTH BREEZE WILL CONTINUE AT ALL THE TAF SITES THROUGH THE PERIOD.
THE WIND WILL AVERAGE 10KTS AT ALL THE TAF SITES...WITH SOME
HIGHER GUSTS POSSIBLE...ESPECIALLY LATER ON THURSDAY.
A COLD FRONT WILL CROSS THE TAF SITES BUT NOT UNTIL THURSDAY NIGHT.
LOOK FOR MVFR AND POSSIBLY EVEN IFR CONDITIONS HEADING INTO
THURSDAY NIGHT.
OUTLOOK...
FRIDAY - SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA...SHSN.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A SOAKING RAINFALL IS EXPECTED MAINLY THURSDAY AFTERNOON THROUGH
THURSDAY NIGHT. WE DID NOT ASSIGN A "WET FLAG" TO OUR NFDRS
SINCE THE BULK OF THE RAIN WILL NOT FALL UNTIL AFTER 100 PM
THURSDAY.
RAINFALL AMOUNTS SHOULD BE A QUARTER INCH OR MORE EVERYWHERE.
IT DRIES OUT FRIDAY WITH A NORTHWEST WIND 5- 15 MPH.
ANOTHER CLIPPER TYPE SYSTEM COULD BRING RAIN OR SNOW SHOWERS
SATURDAY NIGHT...ESPECIALLY NORTH AND WEST OF ALBANY. THERE
MIGHT BE SOME MINOR ACCUMULATIONS OF SNOW.
MUCH COLDER AIR WORKS IN ON GUSTY WINDS FOR THE LATER PORTION OF THE
WEEKEND.
&&
.HYDROLOGY...
A COLD FRONT WILL BRING A ROUND OF RAIN SHOWERS TO THE REGION
LATER THURSDAY INTO THURSDAY NIGHT.
THIS IS A PROGRESSIVE SYSTEM...SO IT WILL NOT LINGER TOO LONG.
IT DRIES OUT BY FRIDAY.
RAINFALL AMOUNTS LOOK TO BE HALF AN INCH TO AROUND AN INCH IN
THE VALLEYS...POSSIBLY UP TO TWO INCHES ACROSS THE HIGHER TERRAIN...
OF THE SOUTHERN GREENS AND BERKSHIRES.
THIS RAIN WILL PRODUCE WITHIN BANK RISES...MAYBE A FEW SPOTS
APPROACHING ACTION STAGE. NO FLOODING EXPECTED.
COOLER AND DRIER WEATHER WILL RETURN FRIDAY INTO THE FIRST HALF
OF THE WEEKEND. ANOTHER SYSTEM MAY BRING LIGHT PCPN IN THE FORM OF
RAIN/SNOW SHOWERS SATURDAY NIGHT INTO SUNDAY WITH LITTLE OR NO HYDROLOGICAL
IMPACTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/GJM
NEAR TERM...HWJIV/GJM
SHORT TERM...HWJIV/KL
LONG TERM...WASULA
AVIATION...GJM
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV/KL/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
646 PM EST WED NOV 18 2015
.SYNOPSIS...
A WARM FRONT WILL WORK ACROSS OUR REGION TONIGHT...KEEPING
TEMPERATURES MILD UNDER A CANOPY OF INCREASING CLOUDS. SPOTTY
DRIZZLE WILL BREAK OUT EARLY THURSDAY...FOLLOWED BY HEAVIER
SHOWERS LATER IN THE DAY WHICH WILL BE AHEAD OF A COLD FRONT THAT
WILL CROSS OUR REGION THURSDAY NIGHT. COOLER DRIER AIR WILL FOLLOW
FOR FRIDAY... FOLLOWED BY EVEN COLDER AIR AND SOME SHOWERS OF RAIN
OR SNOW FOR LATER IN THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 630 PM EST...CLOUDS CONTINUED TO OVERSPREAD THE REGION.
TEMEPRATURES REMAINED MILD...BETWEEN THE MID 40S AND LOWER 50S MOST
PLACES...AND UPPER 30S TO LOWER 40S OVER EXTREME EASTERN BERKSHIRE
COUNTY AND WINDHAM COUNTY.
A SOUTH TO SOUTHEAST BREEZE AVERAGED 10-15 MPH...WITH SOME GUSTS TO
20 MPH OR A LITTLE HIGHER.
EVEN FURTHER SOUTH ACROSS THE MID ATLANTIC...TEMPERATURES WERE IN
THE 60S WITH DEWPOINTS SURGING THROUGH THE 40S. THE LEADING EDGE OF
THIS MILDER AND MORE MOIST AIR MASS WAS PRODUCING THE STRATUS
WHICH CONTINUED TO SPREAD NORTH AND WAS NOW COVERING ALL BUT THE
NORTHERNMOST AREAS. THESE CLOUDS...ADDITIONAL WARM AIR ADVECTION
AND A PERSISTENT BREEZE SHOULD KEEP TEMPERATURES FROM FALLING MUCH
AT ALL. THEREFORE...WE WENT A BIT HIGHER THAN ALL MACHINE GUIDANCE
REGARDING OVERNIGHT LOWS.
LOWS WILL BE IN THE 40S...UPPER 40S LOCALLY IN THE CAPITAL REGION.
AS THE MOISTURE DEEPENS OVERNIGHT THERE MIGHT BE A LITTLE SPOTTY DRIZZLE...
MAINLY ACROSS OUR CATSKILLS DUE TO UPSLOPE BUT EVEN THE MID HUDSON VALLEY
LITCHFIELD AND THE SOUTHERN BERKSHIRES COULD SEE SOME SPOTTY DRIZZLE BY
MIDNIGHT. BY DAYBREAK...EVERYONE COULD SEE A LITTLE SPOTTY DRIZZLE OR A LIGHT
SHOWER ON AN ISOLATED BASIS.
THE SOUTH TO SOUTHEAST BREEZE WILL AVERAGE 5-15 MPH TONIGHT...WITH SOME
HIGHER GUSTS...ESPECIALLY ACROSS THE HIGHER TERRAIN.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
BY THURSDAY...OUR WHOLE AREA WILL BE IN A MOIST MILD AIR MASS
WITH A COLD FRONT RAPIDLY APPROACHING FROM THE WEST.
THIS IS THE SAME SYSTEM THAT PRODUCED QUITE AN ARRAY OF FOUL WEATHER
OUT WEST...INCLUDING SEVERE WEATHER AND EVEN BLIZZARD CONDITIONS.
NEITHER IS EXPECTED FOR US (INSTABILITY NOT THERE FOR ANY REAL
CONVECTION). A RUMBLE OF THUNDER IS CERTAINLY POSSIBLE BUT WITH
SHOWALTER VALUES >0 AND CAPE VALUES NEAR 0 J/KG WILL KEEP
ANY MENTION OF THUNDERSTORMS OUT OF THE GRIDS FOR NOW.
THAT SAID...WITH PWATS SOARING PAST AN INCH....TWO STANDARDS ABOVE
NORMAL. THE COMBINATION OF THIS MOISTURE...THE FRONT...SHORTWAVE
ENERGY AND OUR AREA COMING UNDER THE DIVERGENT AREA OF THE RR 100KT
NIGHT BY EVENING...ALL POINT TO ROUND OF SHOWERS...SOME CONTAINING
MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL.
WHAT IS A LITTLE DIFFERENT FROM PREVIOUS RUNS...THERE IS LESS OF TENDENCY FOR
A SECONDARY WAVE TO DEVELOP ALONG THE TRIPLE POINT...AS THERE WAS
IN SOME EARLIER RUNS. IT LOOKS LIKE A PROGRESSIVE SYSTEM...PRETTY MUCH
WHAT WE HAVE SEEN THIS AUTUMN.
A GUSTY SOUTH WIND WILL ENSUE ON THURSDAY...10-15 MPH...WITH GUSTS
25-35 MPH ACROSS PORTIONS OF THE HIGHER TERRAIN...AND EVEN
SOME SECTIONS OF THE CAPITAL REGION AND MOHAWK VALLEY. DURING
HEAVY SHOWERS...IT IS REMOTELY POSSIBLE THAT SOME GUSTS COULD EVEN
REACH A LITTLE HIGHER THAN THAN THAT...BUT JUST BRIEFLY.
THEREFORE...NO WIND HEADLINES WERE ASSIGNED WITH THIS PACKAGE.
THE ACTUAL COLD FRONT LOOKS TO MOVE ON THROUGH THURSDAY EVENING...
FOLLOWED BY HIGH PRESSURE BEGINNING TO BUILD IN BY EARLY FRIDAY.
IN FACT...THE SKY MIGHT ACTUALLY CLEAR BY DAYBREAK FRIDAY OR AT
LEAST PARTIALLY CLEAR.
BASED ON UPSTREAM TEMPERATURES WELL INTO THE 60S...WE WILL GO SLIGHTLY
HIGHER THAN ALL MACHINE GUIDANCE ON THURSDAY. LOOK FOR HIGHS LOWER TO MID
60S IN THE VALLEYS...MID OR UPPER 50S EVEN ACROSS THE HIGHER TERRAIN.
TURNING COOLER...BUT STILL ABOVE NORMAL THURSDAY NIGHT WITH LOWS
RANGING FROM THE UPPER 30S TO MID 40S.
FRIDAY SHOULD FEATURE AT LEAST PARTIAL SUNSHINE AS THE FLOW LOOKS TOO ANTI-
CYCLONIC FOR MUCH LAKE INDUCED CLOUDS (OUTSIDE OF THE ADIRONDACKS WHERE
UPSLOPE CLOUDS AND A FEW SHOWERS OF RAIN OR RAIN AND WET SNOW MIXED ARE
POSSIBLE).
HIGH TEMPERATURES WILL BE NOTICEABLY COOLER THAN THURSDAY...HIGHS NEAR 50
IN THE VALLEYS...LOWER TO MID 40S HIGHER TERRAIN...CLOSER TO 40
ACROSS THE ADIRONDACKS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE EXTENDED OPENS WITH A POTENT UPPER LEVEL TROUGH APPROACHING FROM
THE GREAT LAKES REGION AND THE MIDWEST. THE UPPER LEVEL TROUGH
TURNS NEGATIVELY TILTED ACCORDING TO LATEST GFS/ECMWF...AS THE SFC
CYCLONE LIFTS NORTHEAST ACROSS THE ERN GREAT LAKES REGION INTO SE
ONTARIO BY 12Z SUN. THERE IS ENOUGH MOISTURE WITH THE OCCLUDED
FRONT TO THE SYSTEM FOR A PERIOD OF RAIN SHOWERS TRANSITIONING TO
SNOW SHOWERS. THERE IS DECENT LIFT AND CONVERGENCE WITH THE
BOUNDARY. SOME LIGHT SNOW ACCUMULATIONS ARE POSSIBLE WITH A COATING
TO LESS THAN A HALF AN INCH IN THE VALLEY AREAS...AND AN INCH OR TWO
OVER THE HIGHER TERRAIN. THE LIGHT SNOW IS SUPPORTED FROM SOME OF
THE ENSEMBLES. THE LATEST GEFS PLUME DIAGRAM YIELDS ABOUT A TENTH OF
AN INCH OF SNOWFALL FOR ALBANY WITH PERHAPS A HALF DOZEN MEMBERS OR
SO. LOWS SAT NIGHT WILL RANGE FROM THE MID AND U20S OVER THE MTNS TO
U20S TO L30S OVER THE VALLEYS.
SUNDAY WILL BE A BLUSTERY AND COLD DAY WITH THE LONG-WAVE TROUGH
AXIS APPROACHING THE REGION. A SECONDARY COLD FRONT OR SFC TROUGH
WILL MOVE THROUGH WITH H850 TEMPS FALL TO -7C TO -10C. SOME SCT
SNOW AND RAIN SHOWERS ARE POSSIBLE. THE RAIN SHOWERS WILL BE MAINLY
WHERE THE BOUNDARY LAYER WARMS ENOUGH WITH TEMPS IN THEN 40-45F
RANGE. THE HIGHER POPS WILL BE NORTH AND WEST OF THE CAPITAL
DISTRICT AND THE MOHAWK RIVER VALLEY. SOME ADDITIONAL LIGHT SNOW
ACCUMS ARE POSSIBLE OVER THE WRN DACKS...ERN CATSKILLS...AND SRN
GREENS. HIGHS WILL BE MAINLY IN THE U30S TO L40S IN THE
VALLEYS...AND LOWER TO U30S OVER THE HIGHER TERRAIN...EXCEPT SOME
U20S IN THE SRN DACKS.
SUNDAY NIGHT INTO MONDAY...A COLD AIR MASS BUILDS IN FROM THE OHIO
VALLEY WITH SOME LAKE EFFECT SNOWFALL POSSIBLE BASED ON THE MEDIUM
RANGE GUIDANCE. LOCATIONS IN THE WRN DACKS...AND W-CNTRL MOHAWK
VALLEY MAY GET AT LEAST SOME LIGHT SNOW ACCUMS. THE REST OF THE FCST
AREA WILL REMAIN DRY...BUT COLD. THE LATEST GFS H850 TEMPS FALL TO
-10C TO -13C OVER THE FCST AREA. LOWS WILL BE IN THE MID AND U20S IN
THE VALLEYS...AND TEENS TO L20S OVER THE MTNS. HIGHS ON MONDAY
RANGE FROM THE U30S TO L40S IN THE VALLEY AREAS...AND U20S TO M30S
OVER THE MTNS.
MONDAY NIGHT INTO TUESDAY...THE LAKE EFFECT SNOWFALL SHOULD
TAPER...AS THE FLOW BECOMES MORE ZONAL. A WEAK DISTURBANCE IN THE
ZONAL FLOW COULD BRING A SLIGHT CHC OF SHOWERS TUE AFTERNOON WEST OF
THE MOHAWK VALLEY. THE ECMWF REMAINS DRY. TEMPS MODERATE TO
SEASONAL VALUES ON TUESDAY WITH SOME MID AND U40S IN THE CAPITAL
DISTRICT...TACONICS...MID HUDSON VALLEY...AND NW CT. U30S TO L40S
ARE COMMON NORTH AND WEST.
TUESDAY NIGHT INTO WEDNESDAY...HIGH PRESSURE WILL RIDGE BACK IN OVER
THE NORTHEAST WITH FAIR AND DRY WEATHER FOR THE MID WEEK...AND
SEASONABLE TEMPS.
OVERALL...TEMPS WILL AVERAGE NEAR NORMAL WITH PCPN BELOW NORMAL IN
THE LONG TERM.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
MVFR CIGS ALREADY OCCURRING AT KPOU/KPSF...AND EXPECT MVFR CIGS TO
MOVE INTO KALB ND KGFL BEFORE MIDNIGHT. THEN MVFR CIGS AND
POSSIBLE MVFR VSBYS WILL OCCUR FOR THE REST OF THE NIGHT AS SOME
FOG OR DRIZZLE DEVELOPS ACROSS THE REGION. IFR CIGS ARE ALSO
POSSIBLE AT KPOU/KPSF LATE TONIGHT...ESPECIALLY AT KPSF WHERE THE
IFR CIGS COULD START AROUND 06Z.
MVFR/IFR CIGS WILL PERSIST INTO THE MORNING...BUT THE DRIZZLE AND
FOG WILL GIVE WAY TO MORE SHOWERY PCPN AS THE COLD FRONT
APPROACHES FROM THE WEST. EXPECT THE WIDESPREAD SHOWERS TO BEGINN
AROUND 15Z/16Z...WITH IFR CIGS AND MVFR VSBYS OCCURING AT ALL THE
TAF SITES THROUGH THE REST OF THE TAF PERIOD ENDING AT 00Z FRIDAY.
A SOUTH BREEZE WILL CONTINUE AT ALL THE TAF SITES THROUGH THE PERIOD.
THE WIND WILL AVERAGE 10KTS AT ALL THE TAF SITES...WITH SOME
HIGHER GUSTS POSSIBLE...ESPECIALLY LATER ON THURSDAY.
A COLD FRONT WILL CROSS THE TAF SITES BUT NOT UNTIL THURSDAY NIGHT.
LOOK FOR MVFR AND POSSIBLY EVEN IFR CONDITIONS HEADING INTO
THURSDAY NIGHT.
OUTLOOK...
FRIDAY - SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA...SHSN.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A SOAKING RAINFALL IS EXPECTED MAINLY THURSDAY AFTERNOON THROUGH
THURSDAY NIGHT. WE DID NOT ASSIGN A "WET FLAG" TO OUR NFDRS
SINCE THE BULK OF THE RAIN WILL NOT FALL UNTIL AFTER 100 PM
THURSDAY.
RAINFALL AMOUNTS SHOULD BE A QUARTER INCH OR MORE EVERYWHERE.
IT DRIES OUT FRIDAY WITH A NORTHWEST WIND 5- 15 MPH.
ANOTHER CLIPPER TYPE SYSTEM COULD BRING RAIN OR SNOW SHOWERS
SATURDAY NIGHT...ESPECIALLY NORTH AND WEST OF ALBANY. THERE
MIGHT BE SOME MINOR ACCUMULATIONS OF SNOW.
MUCH COLDER AIR WORKS IN ON GUSTY WINDS FOR THE LATER PORTION OF THE
WEEKEND.
&&
.HYDROLOGY...
A COLD FRONT WILL BRING A ROUND OF RAIN SHOWERS TO THE REGION
LATER THURSDAY INTO THURSDAY NIGHT.
THIS IS A PROGRESSIVE SYSTEM...SO IT WILL NOT LINGER TOO LONG.
IT DRIES OUT BY FRIDAY.
RAINFALL AMOUNTS LOOK TO BE HALF AN INCH TO AROUND AN INCH IN
THE VALLEYS...POSSIBLY UP TO TWO INCHES ACROSS THE HIGHER TERRAIN...
OF THE SOUTHERN GREENS AND BERKSHIRES.
THIS RAIN WILL PRODUCE WITHIN BANK RISES...MAYBE A FEW SPOTS
APPROACHING ACTION STAGE. NO FLOODING EXPECTED.
COOLER AND DRIER WEATHER WILL RETURN FRIDAY INTO THE FIRST HALF
OF THE WEEKEND. ANOTHER SYSTEM MAY BRING LIGHT PCPN IN THE FORM OF
RAIN/SNOW SHOWERS SATURDAY NIGHT INTO SUNDAY WITH LITTLE OR NO HYDROLOGICAL
IMPACTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/GJM
NEAR TERM...HWJIV/GJM
SHORT TERM...HWJIV/KL
LONG TERM...WASULA
AVIATION...GJM
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV/KL/WASULA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
356 PM EST TUE NOV 17 2015
.DISCUSSION...
TONIGHT AND WEDNESDAY...ONSHORE GRADIENT WINDS HAVE STEADILY
INCREASED AND BREEZY CONDITIONS WILL CONTINUE INTO THE OVERNIGHT
AT THE BEACHES. MOISTURE SUITABLE FOR INCREASING MARINE SHOWERS IS
EXPECTED AS STRENGTH OF THE OVERLYING RIDGE SUBSIDES OVER THE
LOCAL ATLC WATERS. ONSHORE FLOW @ BOUNDARY LAYER UPWARDS OF 20 TO
25 KT SHOULD ALLOW FOR DIURNAL REDEVELOPMENT OF MARINE SOURCE PCPN
AS INDICATED BY LTST HRRR GUID ALONG THE ENTIRE COAST WITH
SUITABLE WINDS PUSHING SHOWERS WELL INLAND. BEST DEVELOPED CU
BANDS WILL BE ABLE TO PRODUCE SOME MEASURED RAIN AMOUNTS OF .10
TO .20 INCHES INTO EARLY WED AS THEY COME ASHORE. LOWS WILL REMAIN
MILD WITH TEMPS IN THE UPR 60S TO MID 70S.
LINGERING SHOWERS DURING WED IN VEERING WIND FLOW PATTERN WITH
REGIME OF SE-LIES LEADING TO A FURTHER INCREASE IN AVBL MOISTURE
WITH NEAR RECORD WARM AND PARTLY SUNNY CONDITIONS. SCT RAIN CVRG
AREAWIDE WL BE USED IN THE FORECAST
THU-FRI...
STORM SYSTEM DVLPG OVER THE CENTRAL PLAINS WILL LIFT N AND MERGE
WITH A SECOND LOW THAT WILL PUSH OUT OF THE PAC NW... MERGER
OCCURRING OVER THE GREAT LAKES/CANADIAN PLAINS REGION BY DAYBREAK
THU. MID/UPR LVL WIND PATTERN ACRS THE CONUS IS HIGHLY
AMPLIFIED....SUGGESTING A LARGE/DEEP HI PRES RIDGE EXTENDING FROM
ERN CANADA TO THE YUCATAN CHANNEL WILL SLOWLY GIVE GROUND TO THE
NEXT THAT WILL AFFECT CENTRAL FL. INDEED...BOTH GFS/ECMWF MODELS
INDICATE THE FRONT...CURRENTLY PUSHING OFF THE TX COAST...WILL ONLY
MAKE IT TO THE CAROLINA COAST/NE GOMEX BY 12Z THU BEFORE STALLING
OVER THE PANHANDLE/NRN PENINSULA BY 12Z FRI.
THE SLOW MOVING/STALLING FRONT WILL SPELL A WET END TO THE WORK WEEK
AS DEEP MOISTURE WILL HAVE PLENTY TO POOL WITHIN THE FRONTAL TROF...
PWAT VALUES INCREASING TO ARND 1.7"-1.8" BY DAYBREAK THU...
FLUCTUATING BTWN 1.8"-2.0" THRU SUNSET FRI BEFORE THE FRONT DRIFTS S
OF THE I-4 CORRIDOR AND ALLOWS DRIER MID LVL AIR BEGINS TO FILTER
INTO THE STATE.
THE FRONT SHOULD HAVE RESPECTABLE JET SUPPORT GIVEN THE 120-140KT
H30-H20 STREAK PUSHING ACRS THE RIO GRANDE VALLEY...AS WELL AS
COOLING MID LVL TEMPS AS AN H50 THERMAL TROF ASSOCD WITH THE JET
WORKS ITS WAY ACRS THE NRN GULF COAST. HOWEVER...THE SATURATED
AIRMASS INDICATED BY THE MODELS WILL IMPEDE SFC HEATING AND
DESTABILIZATION. FURTHERMORE...THE RIDGE WILL SAP MUCH OF THE
STRENGTH OF THE APPROACHING FRONT WHILE DEFLECTING MOST OF THE MID
LVL VORTICITY INTO THE DEEP SOUTH. WILL KEEP SLGT CHC OF TSTMS IN
THE FCST AS THE FRONT SAGS ACRS THE I-4 CORRIDOR...REDUCING PRECIP
TO 30-40PCT CHC SHRAS ON FRI. AFTN MAX TEMPS L/M80S...MIN TEMPS
U60S/L70S AHEAD OF THE FRONT...L/M60S BEHIND IT.
SAT-TUE...(PREV DISC)
THE SLOW MOVING FRONT SHOULD FINALLY GET A KICK THROUGH THE LOCAL
AREA ON SUN AS A STRONG TROUGH ROTATES ACROSS THE MID PART OF THE
COUNTRY...DRIVING A REINFORCING FRONT OFF THE EASTERN SEABOARD. THE
00Z ECMWF...WHICH HAD BEEN SHOWING MUCH MORE DRYING AND COOLING
BEHIND THE FIRST FRONT...NOW HAS A SLOWER SOLUTION CLOSER TO THE GFS
AND INDICATES SAT/SAT NIGHT WILL BE QUITE WET. CONSENSUS POPS DID
NOT PICK UP ON THIS YET AND WERE 20-30 PERCENT...BUT EXPECT LATER
RUNS WILL SHOW HIGHER VALUES. THE GFS AND ECMWF BOTH SHOWED MORE
COOLING/DRYING FOR MON-TUE THOUGH AND SLIGHTLY BELOW NORMAL READINGS
MAY BE IN ORDER FOR EARLY NEXT WEEK.
&&
.AVIATION...
VFR CONDITIONS MIXED WITH BRIEF LOWER CLOUD CVRG NR FL 030-040 IN
ONSHORE MOVING SHOWERS. BEST CHC FOR ANY CIG INTERRUPTIONS WILL
BE NEAR THE CST AND TO SOME DEGREE INLAND THROUGH THE OVERNIGHT
AND INTO EARLY WED. SFC WIND G NR 25KT ALONG THE CST THIS AFT/EVE
THROUGH 02Z WED.
&&
.MARINE...
TONIGHT AND WED...SCA AREA WIDE FOR WINDS/SEAS WL BE IN EFFECT AT
4 PM AND PERSIST THROUGH WED NIGHT AS FULL STRENGTH OF ONSHORE
GRADIENT WINDS MANIFESTS. CHOPPY SEAS BUILDING TO 7 TO 8 FEET
WELL OFFSHORE AND AROUND 6 TO 7 FEET TONIGHT NEAR THE COAST AND
THROUGH WEDNESDAY.
THU-THU NIGHT...BRISK SERLY FLOW DIMINISHING TO A GENTLE TO MODERATE
S/SE BREEZE THRU THE DAY AS THE COLD FRONT SLOWS ITS MARCH ACRS THE
PANHANDLE/ERN GOMEX. WINDS SHIFTING TO A LIGHT TO GENTLE W/NWRLY
BREEZE OVERNIGHT AS THE FRONT SAGS INTO THE LCL ATLC WATERS...MORE
WRLY COMPONENT S OF SEBASTIAN INLET...MORE NRLY COMPONENT N OF THE
INLET. DIMINISHING WINDS WILL ALLOW SEAS TO SUBSIDE FROM TO 3-5FT
NEARSHORE AND 4-6FT OFFSHORE. SHRAS LIKELY WITH THE FROPA...SLGT CHC
TSRAS.
FRI-FRI NIGHT...POST FRONTAL HI PRES RIDGE WILL PUSH OFF THE MID
ATLC COAST. WINDS WILL UNDERGO A SLOW BUT STEADY SHIFT AREAWIDE. N
OF SEBASTIAN INLET A GENTLE TO MODERATE N/NE BREEZE WILL PREVAIL
THRU THE DAY...BCMG A LIGHT TO GENTLE ERLY BREEZE OVERNIGHT. FROM
THE INLET SWD...A LIGHT TO GENTLE NE BREEZE WILL PREVAIL THRU THE
DAY...BCMG A LIGHT S/SE BREEZE OVERNIGHT. SEAS 3-5FT NEARSHORE AND
4-6FT OFFSHORE. CHC SHRAS AREAWIDE.
SAT-SAT NIGHT...LCL PGRAD WILL SLACKEN AS A STRONG HI PRES RIDGE
FORCES THE FRONTAL TROF TO STALL OVER SE FL. SHIFTING FLOW ACRS THE
LCL ATLC...E/SE AREAWIDE EARLY IN THE DAY...BY SUNSET BCMG N/NE FROM
SEBASTIAN INLET NWD... THEN A GENTLE TO MODERATE N/NW BREEZE
OVERNIGHT. INCREASING N/NE SWELLS THRU THE PD...SEAS BUILDING TO
4-6FT NEARSHORE AND 5-7FT OFFSHORE. CHC SHRAS.
SUN-SUN NIGHT...FRESHENING N/NERLY BREEZE WILL PUSH THE NEW SWELL
TRAIN DOWN THE E FL COAST...GENERATING ROUGH TO HAZARDOUS BOATING
CONDS. MODERATE TO FRESH N/NE BREEZE...SEA BUILDING TO 6-8FT
NEARSHORE AND 8-10FT OFFSHORE. CHC SHRAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 72 84 73 80 / 30 30 40 60
MCO 71 86 71 83 / 20 30 40 60
MLB 77 85 74 82 / 30 30 40 60
VRB 75 84 74 82 / 30 30 30 60
LEE 71 86 72 81 / 20 30 40 60
SFB 70 86 71 81 / 20 30 40 60
ORL 72 86 72 82 / 20 30 40 60
FPR 75 84 74 82 / 40 30 30 60
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY 4 PM TODAY UNTIL 10 PM EST WEDNESDAY
FOR FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 0-20
NM-FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 20-60
NM-SEBASTIAN INLET TO JUPITER INLET 0-20 NM-SEBASTIAN INLET
TO JUPITER INLET 20-60 NM-VOLUSIA-BREVARD COUNTY LINE TO
SEBASTIAN INLET 0-20 NM-VOLUSIA-BREVARD COUNTY LINE TO
SEBASTIAN INLET 20-60 NM.
&&
$$
SHORT TERM...PENDERGRAST
LONG TERM....BRAGAW
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
247 PM CST TUE NOV 17 2015
.SHORT TERM...(Tonight)
ISSUED AT 243 PM CST TUE NOV 17 2015
993 mb surface low pressure over central KS to eject into sw MN by
dawn Wed as 536 dm 500 mb low over OK panhandle moves to near the
NE/KS/MO border. A lull in the showers is occuring this afternoon
from I-55 southeast and this break could move into parts of the IL
river valley late this afternoon too. The HRRR model seems to be
reflecting this trend the best and followed it for tonight`s
precipitation forecast. Large area of showers over MO into southeast
IA and nw IL to spread eastward across central IL tonight and
overspread eastern IL late this evening and overnight. Not much
thunder activity so far today but SPC has general risk of thunder
over CWA into tonight and will continue to carry isolated
thunderstorms though diminishing thunder chances from west to east
later tonight. Up to an additional 1 inch of rain expected into
early Wed morning and this is falling on top of 1 to 2 inches that
has already fallen over the area since Monday. Will continue the
flood watch over sw half of CWA through 6 am Wednesday and may be
able to cancel early in western portion with 3 am forecast package
tonight as heavier rain band shifts into eastern IL later tonight.
Strong se winds 15-30 mph and gusts as highs as 30-40 mph to keep
mild lows in the mid to upper 50s which is a bit above normal highs
for mid November.
&&
.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 243 PM CST TUE NOV 17 2015
A strong storm system will continue to impact central and southeast
Illinois to start the day Wednesday, although the steadier rainfall
should be limited to the far eastern extent of the forecast area.
While the heavier rains should be over or quickly ending on
Wednesday, the gusty winds will persist. In fact, as the associated
upper-level cold pool approaches, and surface cold front lags
behind, the steeper low-level lapse rates support even stronger
winds than today. Would not be surprised to see gusts to around 40
MPH for much of the day, and the need for a Wind Advisory will need
to be monitored closely.
Quiet and cooler weather will spread across the region behind the
major system for Thursday and most of Friday as high pressure builds
into the area. While temperatures during the period will be
significantly cooler than we have seen lately, they are much closer
to normal for mid-November.
Models are coming into better agreement regarding a weather
disturbance to end the week. A significant short wave is progged to
translate through the shallower broad trof across North America,
with the trof axis crossing the Midwest from Friday night into
Saturday. This short wave is expected to be accompanied a clipper-
type low pressure system as it moves through. The system is expected
to have precipitation associated with it, and most should fall on
the cool side of the system as is typical with clippers. While the
exact timing/track of the clipper is still in doubt, confidence is
building that most of the forecast area should see precipitation.
Thermal profiles support most, if not all, of the precipitation to
fall in the form of snow. However, if the system arrives early
enough Friday night, it may be warm enough for rain at the onset.
Also, given the strength of the wave, and CAA it its wake, expect
temperatures on Saturday to remain steady or fall as the system
clears the area. Many areas are not likely to make it out of the 30s
Saturday and Sunday. Overall, this system will need to be monitored
closely as it has the potential to bring the first accumulating snow
of the season to parts of the forecast area. However, the warm
ground temperatures should mitigate this threat to some degree.
Cooler than normal temperatures will linger through the end of the
forecast. An additional disturbance may impact the area by Tuesday,
but the current model consensus supports dry weather beyond Saturday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1155 AM CST TUE NOV 17 2015
IFR to low end MVFR ceilings and IFR to MVFR visibilites with
showers to occur this afteroon and tonight. MVFR ceilings expected
Wed morning and vsbys improving to VFR as showers diminish from
the west during Wed morning. High resolution models like HRRR and
RUC show a lull in showers over central and eastern IL developing
during the afternoon and into the evening. Then a larger band of
showers and isolated thunderstorms to spread eastward across IL
during tonight, likely not reaching eastern IL until overnight.
Windy conditions to continue with se winds 18-25 kts and gusts of
27-37 kts through tonight and veering more south Wed morning.
Strong 993 mb surface low pressure over sw KS into OK panhandle
and 536 dm 500 mb low to eject ne into the upper MS river valley
by 18Z/noon Wed.
&&
.ILX Watches/Warnings/Advisories...
Flood Watch through late tonight for ILZ036-040>042-047>054-056-
061>063-066>068-071>073.
&&
$$
SHORT TERM...07
LONG TERM...BAK
AVIATION...07
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1157 AM CST TUE NOV 17 2015
.UPDATE...
ISSUED AT 1045 AM CST TUE NOV 17 2015
Forecast looks pretty good today and just had to increase the
wind speeds a bit higher today, with southeast winds 20-30 mph and
gusts of 30-40 mph. Continued the flood watch for sw CWA through
tonight where 1-2 inches of rain has fallen past 24 hours and
additional 1.25-1.75 inches rest of today and through tonight
with locally higher amounts from Springfield sw with occasional
showers and isolated thunderstorms. Temperatures currently in the
mid 50s to around 60F with milder highs this afternoon of 60-65F.
2nd batch of showers with pockets of moderate to heavy rains
starting to break up over sw half of CWA late this morning as its
lifting ne. 3rd batch of showers and isolated thunderstorms over
MO will spread across western CWA during the afternoon and evening
and into eastern IL overnight. So could be a break in showers for
a time this afternoon and evening especially over eastern/se IL.
Strong 536 dm 500 mb low over the OK panhandle while associated
993 mb surface low pressure from north texas into sw KS and will
eject ne into eastern KS this evening. KILX 12Z precipitable water
values was 1.43 inches and ranked as 10th highest in November and
only 0.10 inches from the highest. Precipitable water values to
peak near record levels between 1.50 and 1.60 inches this
afternoon and into tonight to support moderate to heavy rainfall.
ILX will be doing a special 18Z upper air flight today.
&&
.SHORT TERM...(Today)
ISSUED AT 253 AM CST TUE NOV 17 2015
The second in a series a waves will move across the CWA this
morning. Based on radar and satellite trends, believe showers will
diminish some later this afternoon...in the eastern part of the CWA.
So highest pops will be in the west today. Southeast winds will
remain gusty with gusts over 30 mph at times. As long as the weather
system remains west of the area, pressure gradient will remain
tight, continuing the gusty winds. These gusty winds should help the
warm air advection, causing afternoon temps to be much warmer than
normal.
.LONG TERM...(Tonight through Monday)
ISSUED AT 253 AM CST TUE NOV 17 2015
Track of the upper low currently over northeast New Mexico will take
it into northeast Kansas by early Wednesday, before it opens up and
becomes absorbed into a digging wave in the northern stream. High-
resolution models showing consensus in maintaining a break in the
rain across the eastern CWA late afternoon into the first part of
the evening, but a narrow area of showers will be advancing east
with time as the associated frontal boundary moves into western
Illinois after midnight. Precipitable water values remain off the
charts with values around 1.6-1.7 inches advertised by the NAM and
GFS much of today and this evening, so heavier rains remain likely
with the showers and isolated storms. Flood watch will remain in
place, with the most likely places to experience any flooding
generally from Havana-Effingham westward before the showers weaken
post-midnight. Temperatures expected to remain fairly steady in the
60s much of the night with the strong southerly wind ahead of the
boundary, before finally tailing off late night as the front pushes
east.
A significant surge of colder air will push into the central U.S.
beginning late Wednesday, with a broad trough covering most of the
CONUS by Thursday afternoon. Rather breezy pattern to stick around
in this flow, although winds will be diminishing from south to north
with time on Thursday. Focus will be shifting toward a fast moving
shortwave that will drop through the western Dakotas on Friday,
developing a surface system near the Nebraska Panhandle. The models
have been struggling a bit recently with trying to pin down this
feature in the fast flow, but they are starting to come into
consensus with a period of light precipitation mainly after midnight
Friday night and continuing into Saturday morning. Forecast
soundings indicate the bulk of this precipitation should fall as
snow, with some mixture at the beginning and end. Ground
temperatures remain rather warm (lower 40s at 4 inches per Illinois
State Water Survey), so would not anticipate much in the way of
accumulation, but a light dusting is not out the question mainly
north of I-74 in the heavier precipitation bands.
The ECMWF is much more intense with the sharpening of the cold upper
trough over the Mississippi Valley this weekend, with the GFS a bit
shallower and faster moving. However, both models quickly trend to a
more moderate temperature pattern early next week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1155 AM CST TUE NOV 17 2015
IFR to low end MVFR ceilings and IFR to MVFR visibilites with
showers to occur this afteroon and tonight. MVFR ceilings expected
Wed morning and vsbys improving to VFR as showers diminish from
the west during Wed morning. High resolution models like HRRR and
RUC show a lull in showers over central and eastern IL developing
during the afternoon and into the evening. Then a larger band of
showers and isolated thunderstorms to spread eastward across IL
during tonight, likely not reaching eastern IL until overnight.
Windy conditions to continue with se winds 18-25 kts and gusts of
27-37 kts through tonight and veering more south Wed morning.
Strong 993 mb surface low pressure over sw KS into OK panhandle
and 536 dm 500 mb low to eject ne into the upper MS river valley
by 18Z/noon Wed.
&&
.ILX Watches/Warnings/Advisories...
Flood Watch through late tonight for ILZ036-040>042-047>054-056-
061>063-066>068-071>073.
&&
$$
UPDATE...07
SHORT TERM...Auten
LONG TERM...Geelhart
AVIATION...07
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1005 PM EST WED NOV 18 2015
.UPDATE...
ISSUED AT 1000 PM EST WED NOV 18 2015
BAND OF RAIN SHOWERS HAS COMPLETELY MOVED OUT OF THE AREA AND THE
FORECAST HAS BEEN UPDATED ACCORDINGLY. WIND STILL GUSTING 20 TO 30
MPH OUT OF THE SSW. NEXT BATCH OF RAIN SHOWERS ARRIVES LATE
TONIGHT...BUT MAINLY INTO TOMORROW MORNING ASSOCIATED WITH NEXT
SHORTWAVE AND SFC TROUGH/COLD FRONT AND DEEPER MOISTURE. LOW LEVEL
TEMPERATURES WILL STILL NOT BE COLD ENOUGH FOR ANY SNOW (H8 TEMPS
-1C TO +1C). THE COLDER AIR PLOWS THROUGH THE REGION VIA
INCREASING VERY GUSTY SW/WSW WINDS THROUGH LATTER MORNING AND
AFTERNOON...FOR WHICH WE WILL START TO SEE CHANGEOVERS TO SNOW
WITH LITTLE TO NO ACCUMULATION. GUSTS IN THE AFTERNOON 35-45 MPH
IN MANY LOCALES...HIGHEST IMMEDIATELY DOWNWIND OF LAKE MICHIGAN
(NW LOWER COAST AND MACKINAC COUNTY OF EASTERN UPPER).
&&
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 323 PM EST WED NOV 18 2015
OCCLUDED SURFACE LOW CENTER HAS REACHED NRN MINNESOTA LATE THIS
AFTERNOON...WITH THE ASSOCIATED COLD FRONT EXTENDING SOUTHWARD THRU
CENTRAL WISCONSIN AND CENTRAL ILLINOIS INTO THE LOWER MISSISSIPPI
VALLEY. WARM/MOIST AIR CONTINUES TO STREAM NORTHWARD OUT OF THE GULF
ALONG AND AHEAD OF THE COLD FRONT...AND INTO MICHIGAN. SFC DWPTS ARE
NOW MAINLY IN THE UPPER 40S ACROSS OUR ENTIRE CWA... WITH ALL LOCAL
OBS REPORTING AT LEAST A PERIOD OF RAIN DURING THE AFTERNOON.
NEXT WAVE OF WIDESPREAD RAIN IS MOVING THRU SRN LWR MICHIGAN TOWARD
OUR CWA...TARGETING THE ERN HALF FOR HIGHEST POPS FOR THE REST OF
THE AFTERNOON INTO THIS EVENING. NAM12...RAP13 AND HRRR ALL SUGGEST
THIS SCENARIO WITH SLIGHT VARIATIONS...AND OVERALL MODEL TRENDS HAVE
BEEN DOWNWARD FOR EXPECTED POPS LATE THIS AFTERNOON THRU TONIGHT. IN
FACT...ALL OF THE ABOVE MODELS NEARLY DISSIPATE THE AREA OF SHOWERS
CURRENTLY DEVELOPING OVER WISCONSIN BEFORE IT CAN REACH MICHIGAN
TONIGHT...HOLDING OFF ON THE REDEVELOPMENT OF BETTER POPS UNTIL
AFTER 12Z THURSDAY. HAVE DIMINISHED POPS FOR TONIGHT...BUT STILL
TARGET ERN SECTIONS OF OUR CWA FOR BEST CHANCE OF RAIN. LOW LEVELS
DO BEGIN TO COOL IN THE WAKE OF THE COLD FRONT TONIGHT...BUT
SUFFICIENTLY COLD AIR TO RESULT IN MIXED PRECIP AND/OR SNOW WILL
HOLD OFF UNTIL TOMORROW. THUS...ALL PRECIP WILL REMAIN LIQUID THRU
THE NIGHT...WITH OVERNIGHT LOWS FALLING INTO THE LOWER 40S.
STRONGEST CORRIDOR OF LOW LEVEL WINDS HAS REACHED OUR CWA...AND SO
FAR HAVE REMAINED JUST BELOW WIND ADVISORY CRITERIA. HAVE SEEN
NOTHING UPSTREAM OVER WISCONSIN TO INDICATE ANY FURTHER
STRENGTHENING OF WIND SPEEDS...AND WE MAY EVEN SEE A SLIGHT DIMINISH
LATER THIS EVENING AND OVERNIGHT. SO...AT THIS POINT...NO WIND
ADVISORY WILL BE NEEDED...BUT WILL CONTINUE TO KEEP A CLOSE EYE ON
LOCAL SURFACE OBS.
&&
.SHORT TERM...(THURSDAY THROUGH SATURDAY)
ISSUED AT 323 PM EST WED NOV 18 2015
HIGH IMPACT WEATHER POTENTIAL: LINGERING WIND CONCERNS THURSDAY.
ADDRESSING POTENTIAL WIDESPREAD SNOW EVENT SATURDAY.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: DEEP TROUGH DIGGING THROUGH
THE CENTRAL PART OF THE COUNTRY...LED IN CHARGE BY OPENING SOUTHERN
STREAM WAVE PIVOTING ACROSS WISCONSIN. FAR UPSTREAM PACIFIC FLOW
REGIME A TOUCH MORE "FLATISH" IN APPEARANCE...WITH ROBUST UPPER JET
CORE PUNCHING THROUGH THE NORTHWEST STATES. PATTERN SET TO GO
THROUGH SOME CHANGES IN THE COMING DAYS...WITH STRONG SECONDARY JET
MAX ACROSS THE NORTH PACIFIC FORCING AMPLIFYING AND TRANSIENT
RIDGING ACROSS THE NORTHEAST PACIFIC. SUBTLE WAVE DIVING DOWN THE
FRONT SIDE OF THIS RIDGE AMPLIFICATION...ALONG WITH THE POTENTIAL
STRENGTHENING OF UPPER JET CORE ALONG RIDGE/TROUGH INTERFACE...COULD
WORK IN TANDEM TO DRUM UP A RATHER SIGNIFICANT SNOW EVENT FOR AT
LEAST SOME ACROSS THE GREAT LAKES HEADING INTO THIS WEEKEND.
OTHERWISE...A MUCH MORE NOVEMBER FEEL EXPECTED THURSDAY INTO THE
WEEKEND...AS TROUGHING AND MODIFIED POLAR AIR DOMINATES.
PRIMARY FORECAST CONCERNS/CHALLENGES: INITIAL CONCERNS CENTERED ON
WIND GUSTS AND LAKE INDUCED SNOW SHOWER POTENTIAL THURSDAY AND
FRIDAY. ATTENTION DIRECTED TO POSSIBLE WINTER STORM IMPACTS HEADING
INTO AND THROUGH SATURDAY.
DETAILS: MAIN SYSTEM CONTINUES TO LIFT WELL NORTH OF THE AREA
TONIGHT AND THURSDAY...DRAGGING MAIN COLD FRONT ACROSS NORTHERN
MICHIGAN THURSDAY MORNING. ATTENDANT CAA AND REMNANT TIGHT PRESSURE
GRADIENT WILL WORK IN TANDEM TO CONTINUE THE GUSTY WINDS...ALTHOUGH
WIND DIRECTION WILL TURN DECIDEDLY MORE SOUTHWEST AFTER FRONTAL
PASSAGE. WINDS LOOK TO BE SUSTAINED AT 15 TO 25 MPH...WITH BUFKIT
MOMENTUM TRANSFER EASILY SUPPORTING WIDESPREAD WIND GUSTS A GOOD 10
OR SO MILES PER HOUR STRONGER...WITH GUSTS PUSHING 40 MPH AT TIMES
ALONG THE EXPOSED LAKE MICHIGAN COAST. BAND OF RAIN/SNOW SHOWERS TO
ACCOMPANY PASSING COLD FRONT...WITH PRECIP COVERAGE NO DOUBT
AUGMENTED BY INCREASING LAKE PROCESSES. COLD AIR WILL ONLY DEEPENING
WITH TIME...WITH AMPLE AIR/WATER TEMPERATURE DIFFERENCE TO CONTINUE
LAKE INDUCED SNOW SHOWERS IN FAVORED WSW-SW FLOW AREAS (TIP OF THE
MITT AND STRAITS). DEEPEST MOISTURE AND BEST SYNOPTIC FORCING
CONTINUES TO REMAIN NORTH OF OUR AREA...AND SAID WIND DIRECTION
MEANS NO MULTI-LAKE CONNECTION. SOUNDINGS SHOW DOWN LOW INVERTED-V
SIGNATURE...INDICATIVE OF UPSTREAM LOWER LEVEL DRY AIR AND NO LAKE
SUPERIOR PRECONDITIONING. SO...DESPITE MORE THAN FAVORABLE DELTA T/S
IN THE HIGH TEENS...JUST NOT SEEING A WHOLE LOT OF POTENTIAL FOR ANY
SIGNIFICANT SNOW ACCUMULATION (NOT MUCH MORE THAN AN INCH).
ABOVE TRENDS CONTINUE THURSDAY NIGHT AND FRIDAY...ALTHOUGH WINDS
GRADUALLY WEAKEN AND SLOWLY VEER WITH TIME. LIMITED MOISTURE
CONTINUES...WITH NO MULTI-LAKE CONNECTION EVER ESTABLISHED.
SO...MOSTLY LIGHT LAKE SNOWS WILL CONTINUE...FOCUSED ACROSS THE TIP
OF THE MITT WHERE ANOTHER INCH OR SO IS EXPECTED BY LATER FRIDAY.
MUCH...MUCH COLDER BY FRIDAY...ALTHOUGH HIGHS IN THE MID 30S/AROUND
40 ABOUT ON PAR FOR THIS TIME OF YEAR.
ATTENTION FRIDAY NIGHT AND SATURDAY DIRECTED AT THAT POTENTIAL SNOW
PRODUCING SYSTEM TALKED ABOUT IN THE OPENING PARAGRAPH. WOULD LOVE
TO OFFER MORE CONCRETE ANSWERS...BUT THERE IS SIMPLY TOO MUCH
UNCERTAINTY TO GO WITH MUCH SPECIFICS JUST YET. UPPER JET CORE AND
SUBTLE WAVE WILL NOT BE FULLY SAMPLED UNTIL TOMORROW...AND EVEN THEN
WOULD NOT BE SURPRISED TO SEE GUIDANCE FLUCTUATIONS GIVEN COMPLEXITY
OF MID AND UPPER LEVEL FEATURES AND THEIR INTERACTION. AS OF
NOW...FULL RANGE OF POSSIBILITIES REMAIN VIABLE...FROM A MUCH
FLATTER AND WEAKER SOLUTION REMAINING WELL TO OUR SOUTH...TO A MORE
FULLY ORGANIZED AND DEEP LAYER STORM BRINGING SIGNIFICANT SNOW
ACCUMULATIONS AND IMPACTS TO MUCH...IF NOT ALL...OF NORTHERN
MICHIGAN. AS IS OFTEN THE CASE...REALITY WILL PROBABLY LIE SOMEWHERE
BETWEEN THIS TWO EXTREMES...WHICH WOULD STILL LIKELY DRIVE SOME
ACCUMULATING SNOW TO AT LEAST PARTS OF NORTHERN LOWER MICHIGAN. NO
DOUBT SYSTEM WILL HAVE TO BE CLOSELY MONITORED...WITH THE MORE
WRAPPED UP SCENARIO (E.G. 00Z ECMWF) SHOWING EXCELLENT LIFT IN THE
DGZ...ENHANCED BANDING POTENTIAL VIA FGEN RESPONSE...AND HINTS OF
SOME REDUCED STABILITY ALOFT. WILL BEGIN TO RAMP UP THIS STORM
POTENTIAL IN OUR LATEST HAZARDOUS WEATHER PRODUCTS AND THROUGH OUR
WEB GRAPHICS. DEFINITELY WORTH MONITORING IN THE COMING DAYS FOR
SURE.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 323 PM EST WED NOV 18 2015
DEPENDING ON HOW SATURDAY`S SYSTEM EVOLVES...COULD STILL BE DEALING
WITH AT LEAST LIGHT SYNOPTIC SNOW ACROSS THE SOUTHEASTERN COUNTIES
TO BEGIN THE PERIOD. HOWEVER...AS THE LOW DEPARTS QUICKLY OFF TO THE
NORTH AND EAST...WINDS SHIFT NORTHERLY SATURDAY NIGHT AND EVENTUALLY
WNW BY SUNDAY MORNING. WITH H8 TEMPS PROGGED TO BE ROUGHLY -13C
ACROSS NRN MI AND DELTA TS ~22C...WOULD EXPECT LES TO KICK IN AND
BRIEFLY TARGET AREAS WEST OF THE 131 CORRIDOR INCLUDING THE TRAVERSE
CITY AND CADILLAC AREAS ALONG WITH NRN CHIPPEWA COUNTY BEFORE
SHIFTING TO MORE WNW FLOW FAVORED LOCATIONS OF NORTHWEST LOWER AND
NRN CHIPPEWA BY EARLY SUNDAY MORNING. SUNDAY EVENING...LLEVEL WINDS
SHIFT WESTERLY...THEN WSW SUNDAY NIGHT AIDING IN WARMING H8 TEMPS
AND AN EVENTUAL SHUT OFF TO THE MAJORITY OF LAKE INDUCED SNOW.
HINTS ARE THERE MONDAY THAT ANOTHER WEAK WAVE MAY SLIDE THROUGH
RATHER ZONAL UPPER LEVEL FLOW TIED TO AN ASSOCIATED NRN JET STREAK
ACROSS THE NORTHERN HALF OF THE CWA...PERHAPS PROVIDING ADDITIONAL
SNOW SHOWER CHANCES. GLOBAL GUIDANCE BEGINS TO LARGELY DIVERGE BY
WEDNESDAY WITH SEVERAL SOLUTIONS POSSIBLE...ALTHOUGH ANOTHER WARM UP
LOOKS TO BE ON TAP FOR THE MIDDLE OF NEXT WEEK INTO PERHAPS THE
THANKSGIVING HOLIDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 707 PM EST WED NOV 18 2015
...STRONG WINDS AND SHOWERY...
STRONG LOW PRESSURE LIFTS UP THROUGH NW ONTARIO OVER THE NEXT 24
HOURS WHICH IS CURRENTLY LIFTING A FRONTAL BOUNDARY THROUGH NRN
MICHIGAN...SWITCHING WINDS FROM SSE TO SSW. A TIGHT PRESSURE
GRADIENT HAS BEEN ALLOWING FOR 35 TO 45 MPH GUSTS. THESE WILL WIND
DOWN THROUGH THE NIGHT. THE NEXT SFC TROUGH/COLD FRONT DRIVES
THROUGH TOMORROW MORNING WHILE WE ALSO SEE SOME PERIODIC AND
GENERALLY LIGHT RAIN SHOWERS...TURNING OVER TO PRIMARILY SNOW
SHOWERS AS COLDER AIR FILTERS INTO THE REGION. LITTLE TO NO
ACCUMULATION...AND NOT EVEN MUCH IN THE WAY OF LOWERED
VSBYS...OUTSIDE OF PLN WHERE THE BETTER SNOWS WILL RESIDE. THIS
SECONDARY TROUGH/COLD FRONT WILL ALSO RESULT IN JUST AS HIGH OF
GUSTS...IF NOT MORE...INCREASING THROUGH THE AFTERNOON TO AS HIGH
AS 40-45 MPH.
CURRENT BAND/SWATH OF RAIN ALONG AND AHEAD OF THE FIRST FRONTAL
PASSAGE WILL CROSS PLN 01-02Z...AND APN 03-04Z. BRIEF REDUCED
VSBYS TO AS LOW AS 2SM IN THIS LINE OF SHOWERS...AND A KICK IN
WIND DIRECTION TO MORE OF A SSW DIRECTION.
WINDS ARE STILL BLOWING QUITE HARD ALOFT...AND DESPITE DECENT
MIXING TO THE SFC...STILL GONNA CARRY LLWS THROUGH THE NIGHT.
&&
.MARINE...
ISSUED AT 323 PM EST WED NOV 18 2015
GALE FORCE WINDS AND HIGH WAVES WILL CONTINUE TO IMPACT ALL
NEARSHORE AREAS THRU TONIGHT (AT LEAST) AND AS DEEP LOW PRESSURE
LIFTS NE INTO S CENTRAL CANADA...PRODUCING A TIGHT LOW LEVEL
PRESSURE GRADIENT ACROSS THE WRN GREAT LAKES REGION. WAVES OF
WIDESPREAD RAIN WILL ALSO CONTINUE TO IMPACT OUR AREA THRU
TONIGHT...BECOMING MIX WITH SNOW ON THURSDAY.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...GALE WARNING UNTIL 5 AM EST THURSDAY FOR LHZ346>349.
GALE WARNING UNTIL 7 AM EST FRIDAY FOR LHZ345.
LM...GALE WARNING UNTIL 7 AM EST FRIDAY FOR LMZ323-341-342-344>346.
LS...GALE WARNING UNTIL 5 AM EST THURSDAY FOR LSZ322.
GALE WARNING UNTIL 7 AM EST FRIDAY FOR LSZ321.
&&
$$
UPDATE...DICKSON
NEAR TERM...MLR
SHORT TERM...MSB
LONG TERM...GILLEN
AVIATION...DICKSON
MARINE...MLR
AREA FORECAST DISCUSSION
NWS GAYLORD MI
718 PM EST WED NOV 18 2015
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 323 PM EST WED NOV 18 2015
OCCLUDED SURFACE LOW CENTER HAS REACHED NRN MINNESOTA LATE THIS
AFTERNOON...WITH THE ASSOCIATED COLD FRONT EXTENDING SOUTHWARD THRU
CENTRAL WISCONSIN AND CENTRAL ILLINOIS INTO THE LOWER MISSISSIPPI
VALLEY. WARM/MOIST AIR CONTINUES TO STREAM NORTHWARD OUT OF THE GULF
ALONG AND AHEAD OF THE COLD FRONT...AND INTO MICHIGAN. SFC DWPTS ARE
NOW MAINLY IN THE UPPER 40S ACROSS OUR ENTIRE CWA... WITH ALL LOCAL
OBS REPORTING AT LEAST A PERIOD OF RAIN DURING THE AFTERNOON.
NEXT WAVE OF WIDESPREAD RAIN IS MOVING THRU SRN LWR MICHIGAN TOWARD
OUR CWA...TARGETING THE ERN HALF FOR HIGHEST POPS FOR THE REST OF
THE AFTERNOON INTO THIS EVENING. NAM12...RAP13 AND HRRR ALL SUGGEST
THIS SCENARIO WITH SLIGHT VARIATIONS...AND OVERALL MODEL TRENDS HAVE
BEEN DOWNWARD FOR EXPECTED POPS LATE THIS AFTERNOON THRU TONIGHT. IN
FACT...ALL OF THE ABOVE MODELS NEARLY DISSIPATE THE AREA OF SHOWERS
CURRENTLY DEVELOPING OVER WISCONSIN BEFORE IT CAN REACH MICHIGAN
TONIGHT...HOLDING OFF ON THE REDEVELOPMENT OF BETTER POPS UNTIL
AFTER 12Z THURSDAY. HAVE DIMINISHED POPS FOR TONIGHT...BUT STILL
TARGET ERN SECTIONS OF OUR CWA FOR BEST CHANCE OF RAIN. LOW LEVELS
DO BEGIN TO COOL IN THE WAKE OF THE COLD FRONT TONIGHT...BUT
SUFFICIENTLY COLD AIR TO RESULT IN MIXED PRECIP AND/OR SNOW WILL
HOLD OFF UNTIL TOMORROW. THUS...ALL PRECIP WILL REMAIN LIQUID THRU
THE NIGHT...WITH OVERNIGHT LOWS FALLING INTO THE LOWER 40S.
STRONGEST CORRIDOR OF LOW LEVEL WINDS HAS REACHED OUR CWA...AND SO
FAR HAVE REMAINED JUST BELOW WIND ADVISORY CRITERIA. HAVE SEEN
NOTHING UPSTREAM OVER WISCONSIN TO INDICATE ANY FURTHER
STRENGTHENING OF WIND SPEEDS...AND WE MAY EVEN SEE A SLIGHT DIMINISH
LATER THIS EVENING AND OVERNIGHT. SO...AT THIS POINT...NO WIND
ADVISORY WILL BE NEEDED...BUT WILL CONTINUE TO KEEP A CLOSE EYE ON
LOCAL SURFACE OBS.
&&
.SHORT TERM...(THURSDAY THROUGH SATURDAY)
ISSUED AT 323 PM EST WED NOV 18 2015
HIGH IMPACT WEATHER POTENTIAL: LINGERING WIND CONCERNS THURSDAY.
ADDRESSING POTENTIAL WIDESPREAD SNOW EVENT SATURDAY.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: DEEP TROUGH DIGGING THROUGH
THE CENTRAL PART OF THE COUNTRY...LED IN CHARGE BY OPENING SOUTHERN
STREAM WAVE PIVOTING ACROSS WISCONSIN. FAR UPSTREAM PACIFIC FLOW
REGIME A TOUCH MORE "FLATISH" IN APPEARANCE...WITH ROBUST UPPER JET
CORE PUNCHING THROUGH THE NORTHWEST STATES. PATTERN SET TO GO
THROUGH SOME CHANGES IN THE COMING DAYS...WITH STRONG SECONDARY JET
MAX ACROSS THE NORTH PACIFIC FORCING AMPLIFYING AND TRANSIENT
RIDGING ACROSS THE NORTHEAST PACIFIC. SUBTLE WAVE DIVING DOWN THE
FRONT SIDE OF THIS RIDGE AMPLIFICATION...ALONG WITH THE POTENTIAL
STRENGTHENING OF UPPER JET CORE ALONG RIDGE/TROUGH INTERFACE...COULD
WORK IN TANDEM TO DRUM UP A RATHER SIGNIFICANT SNOW EVENT FOR AT
LEAST SOME ACROSS THE GREAT LAKES HEADING INTO THIS WEEKEND.
OTHERWISE...A MUCH MORE NOVEMBER FEEL EXPECTED THURSDAY INTO THE
WEEKEND...AS TROUGHING AND MODIFIED POLAR AIR DOMINATES.
PRIMARY FORECAST CONCERNS/CHALLENGES: INITIAL CONCERNS CENTERED ON
WIND GUSTS AND LAKE INDUCED SNOW SHOWER POTENTIAL THURSDAY AND
FRIDAY. ATTENTION DIRECTED TO POSSIBLE WINTER STORM IMPACTS HEADING
INTO AND THROUGH SATURDAY.
DETAILS: MAIN SYSTEM CONTINUES TO LIFT WELL NORTH OF THE AREA
TONIGHT AND THURSDAY...DRAGGING MAIN COLD FRONT ACROSS NORTHERN
MICHIGAN THURSDAY MORNING. ATTENDANT CAA AND REMNANT TIGHT PRESSURE
GRADIENT WILL WORK IN TANDEM TO CONTINUE THE GUSTY WINDS...ALTHOUGH
WIND DIRECTION WILL TURN DECIDEDLY MORE SOUTHWEST AFTER FRONTAL
PASSAGE. WINDS LOOK TO BE SUSTAINED AT 15 TO 25 MPH...WITH BUFKIT
MOMENTUM TRANSFER EASILY SUPPORTING WIDESPREAD WIND GUSTS A GOOD 10
OR SO MILES PER HOUR STRONGER...WITH GUSTS PUSHING 40 MPH AT TIMES
ALONG THE EXPOSED LAKE MICHIGAN COAST. BAND OF RAIN/SNOW SHOWERS TO
ACCOMPANY PASSING COLD FRONT...WITH PRECIP COVERAGE NO DOUBT
AUGMENTED BY INCREASING LAKE PROCESSES. COLD AIR WILL ONLY DEEPENING
WITH TIME...WITH AMPLE AIR/WATER TEMPERATURE DIFFERENCE TO CONTINUE
LAKE INDUCED SNOW SHOWERS IN FAVORED WSW-SW FLOW AREAS (TIP OF THE
MITT AND STRAITS). DEEPEST MOISTURE AND BEST SYNOPTIC FORCING
CONTINUES TO REMAIN NORTH OF OUR AREA...AND SAID WIND DIRECTION
MEANS NO MULTI-LAKE CONNECTION. SOUNDINGS SHOW DOWN LOW INVERTED-V
SIGNATURE...INDICATIVE OF UPSTREAM LOWER LEVEL DRY AIR AND NO LAKE
SUPERIOR PRECONDITIONING. SO...DESPITE MORE THAN FAVORABLE DELTA T/S
IN THE HIGH TEENS...JUST NOT SEEING A WHOLE LOT OF POTENTIAL FOR ANY
SIGNIFICANT SNOW ACCUMULATION (NOT MUCH MORE THAN AN INCH).
ABOVE TRENDS CONTINUE THURSDAY NIGHT AND FRIDAY...ALTHOUGH WINDS
GRADUALLY WEAKEN AND SLOWLY VEER WITH TIME. LIMITED MOISTURE
CONTINUES...WITH NO MULTI-LAKE CONNECTION EVER ESTABLISHED.
SO...MOSTLY LIGHT LAKE SNOWS WILL CONTINUE...FOCUSED ACROSS THE TIP
OF THE MITT WHERE ANOTHER INCH OR SO IS EXPECTED BY LATER FRIDAY.
MUCH...MUCH COLDER BY FRIDAY...ALTHOUGH HIGHS IN THE MID 30S/AROUND
40 ABOUT ON PAR FOR THIS TIME OF YEAR.
ATTENTION FRIDAY NIGHT AND SATURDAY DIRECTED AT THAT POTENTIAL SNOW
PRODUCING SYSTEM TALKED ABOUT IN THE OPENING PARAGRAPH. WOULD LOVE
TO OFFER MORE CONCRETE ANSWERS...BUT THERE IS SIMPLY TOO MUCH
UNCERTAINTY TO GO WITH MUCH SPECIFICS JUST YET. UPPER JET CORE AND
SUBTLE WAVE WILL NOT BE FULLY SAMPLED UNTIL TOMORROW...AND EVEN THEN
WOULD NOT BE SURPRISED TO SEE GUIDANCE FLUCTUATIONS GIVEN COMPLEXITY
OF MID AND UPPER LEVEL FEATURES AND THEIR INTERACTION. AS OF
NOW...FULL RANGE OF POSSIBILITIES REMAIN VIABLE...FROM A MUCH
FLATTER AND WEAKER SOLUTION REMAINING WELL TO OUR SOUTH...TO A MORE
FULLY ORGANIZED AND DEEP LAYER STORM BRINGING SIGNIFICANT SNOW
ACCUMULATIONS AND IMPACTS TO MUCH...IF NOT ALL...OF NORTHERN
MICHIGAN. AS IS OFTEN THE CASE...REALITY WILL PROBABLY LIE SOMEWHERE
BETWEEN THIS TWO EXTREMES...WHICH WOULD STILL LIKELY DRIVE SOME
ACCUMULATING SNOW TO AT LEAST PARTS OF NORTHERN LOWER MICHIGAN. NO
DOUBT SYSTEM WILL HAVE TO BE CLOSELY MONITORED...WITH THE MORE
WRAPPED UP SCENARIO (E.G. 00Z ECMWF) SHOWING EXCELLENT LIFT IN THE
DGZ...ENHANCED BANDING POTENTIAL VIA FGEN RESPONSE...AND HINTS OF
SOME REDUCED STABILITY ALOFT. WILL BEGIN TO RAMP UP THIS STORM
POTENTIAL IN OUR LATEST HAZARDOUS WEATHER PRODUCTS AND THROUGH OUR
WEB GRAPHICS. DEFINITELY WORTH MONITORING IN THE COMING DAYS FOR
SURE.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 323 PM EST WED NOV 18 2015
DEPENDING ON HOW SATURDAY`S SYSTEM EVOLVES...COULD STILL BE DEALING
WITH AT LEAST LIGHT SYNOPTIC SNOW ACROSS THE SOUTHEASTERN COUNTIES
TO BEGIN THE PERIOD. HOWEVER...AS THE LOW DEPARTS QUICKLY OFF TO THE
NORTH AND EAST...WINDS SHIFT NORTHERLY SATURDAY NIGHT AND EVENTUALLY
WNW BY SUNDAY MORNING. WITH H8 TEMPS PROGGED TO BE ROUGHLY -13C
ACROSS NRN MI AND DELTA TS ~22C...WOULD EXPECT LES TO KICK IN AND
BRIEFLY TARGET AREAS WEST OF THE 131 CORRIDOR INCLUDING THE TRAVERSE
CITY AND CADILLAC AREAS ALONG WITH NRN CHIPPEWA COUNTY BEFORE
SHIFTING TO MORE WNW FLOW FAVORED LOCATIONS OF NORTHWEST LOWER AND
NRN CHIPPEWA BY EARLY SUNDAY MORNING. SUNDAY EVENING...LLEVEL WINDS
SHIFT WESTERLY...THEN WSW SUNDAY NIGHT AIDING IN WARMING H8 TEMPS
AND AN EVENTUAL SHUT OFF TO THE MAJORITY OF LAKE INDUCED SNOW.
HINTS ARE THERE MONDAY THAT ANOTHER WEAK WAVE MAY SLIDE THROUGH
RATHER ZONAL UPPER LEVEL FLOW TIED TO AN ASSOCIATED NRN JET STREAK
ACROSS THE NORTHERN HALF OF THE CWA...PERHAPS PROVIDING ADDITIONAL
SNOW SHOWER CHANCES. GLOBAL GUIDANCE BEGINS TO LARGELY DIVERGE BY
WEDNESDAY WITH SEVERAL SOLUTIONS POSSIBLE...ALTHOUGH ANOTHER WARM UP
LOOKS TO BE ON TAP FOR THE MIDDLE OF NEXT WEEK INTO PERHAPS THE
THANKSGIVING HOLIDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 707 PM EST WED NOV 18 2015
...STRONG WINDS AND SHOWERY...
STRONG LOW PRESSURE LIFTS UP THROUGH NW ONTARIO OVER THE NEXT 24
HOURS WHICH IS CURRENTLY LIFTING A FRONTAL BOUNDARY THROUGH NRN
MICHIGAN...SWITCHING WINDS FROM SSE TO SSW. A TIGHT PRESSURE
GRADIENT HAS BEEN ALLOWING FOR 35 TO 45 MPH GUSTS. THESE WILL WIND
DOWN THROUGH THE NIGHT. THE NEXT SFC TROUGH/COLD FRONT DRIVES
THROUGH TOMORROW MORNING WHILE WE ALSO SEE SOME PERIODIC AND
GENERALLY LIGHT RAIN SHOWERS...TURNING OVER TO PRIMARILY SNOW
SHOWERS AS COLDER AIR FILTERS INTO THE REGION. LITTLE TO NO
ACCUMULATION...AND NOT EVEN MUCH IN THE WAY OF LOWERED
VSBYS...OUTSIDE OF PLN WHERE THE BETTER SNOWS WILL RESIDE. THIS
SECONDARY TROUGH/COLD FRONT WILL ALSO RESULT IN JUST AS HIGH OF
GUSTS...IF NOT MORE...INCREASING THROUGH THE AFTERNOON TO AS HIGH
AS 40-45 MPH.
CURRENT BAND/SWATH OF RAIN ALONG AND AHEAD OF THE FIRST FRONTAL
PASSAGE WILL CROSS PLN 01-02Z...AND APN 03-04Z. BRIEF REDUCED
VSBYS TO AS LOW AS 2SM IN THIS LINE OF SHOWERS...AND A KICK IN
WIND DIRECTION TO MORE OF A SSW DIRECTION.
WINDS ARE STILL BLOWING QUITE HARD ALOFT...AND DESPITE DECENT
MIXING TO THE SFC...STILL GONNA CARRY LLWS THROUGH THE NIGHT.
&&
.MARINE...
ISSUED AT 323 PM EST WED NOV 18 2015
GALE FORCE WINDS AND HIGH WAVES WILL CONTINUE TO IMPACT ALL
NEARSHORE AREAS THRU TONIGHT (AT LEAST) AND AS DEEP LOW PRESSURE
LIFTS NE INTO S CENTRAL CANADA...PRODUCING A TIGHT LOW LEVEL
PRESSURE GRADIENT ACROSS THE WRN GREAT LAKES REGION. WAVES OF
WIDESPREAD RAIN WILL ALSO CONTINUE TO IMPACT OUR AREA THRU
TONIGHT...BECOMING MIX WITH SNOW ON THURSDAY.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...GALE WARNING UNTIL 5 AM EST THURSDAY FOR LHZ346>349.
GALE WARNING UNTIL 7 AM EST FRIDAY FOR LHZ345.
LM...GALE WARNING UNTIL 7 AM EST FRIDAY FOR LMZ323-341-342-344>346.
LS...GALE WARNING UNTIL 5 AM EST THURSDAY FOR LSZ322.
GALE WARNING UNTIL 7 AM EST FRIDAY FOR LSZ321.
&&
$$
NEAR TERM...MLR
SHORT TERM...MSB
LONG TERM...GILLEN
AVIATION...DICKSON
MARINE...MLR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
349 PM EST TUE NOV 17 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 341 PM EST TUE NOV 17 2015
12Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A DEEP S FLOW OVER
THE WRN GREAT LKS BTWN A HI AMPLITUDE RDG ORIENTED FM JAMES BAY TO
THE SE CONUS AND AN UPR TROF IN THE PLAINS EXTENDING N OF A CUTOFF
H5 LO NEAR THE TX PANHANDLE. THIS STRONG S WIND BTWN THESE UPR
FEATURES...WITH 12Z H925 WINDS UP TO 40-45 KTS NOTED FM GRB INTO THE
LOWER-MID MS RIVER VALLEY...IS DRAWING SOME VERY MOIST AIR TOWARD
THE CWA. 12Z ROABS SHOW AN AREA OF PWAT BTWN 1.00 AND 1.50 INCH JUST
TO THE SW...AS MUCH AS 250-350 PCT OF NORMAL. THE 12Z APX RAOB DOES
SHOW AN AREA OF LINGERING LLVL DRY AIR IN NRN LOWER MI. SOME SCT
SHOWERS DID IMPACT MAINLY THE CENTRAL EARLIER...BUT ADVECTION OF
SOME LLVL DRY AIR FM THE DRY AIR SOURCE RELATED TO THE 12Z APX RAOB
TENDED TO DIMINISH THESE SHOWERS IN THE ABSENCE OF SGNFT DYNAMIC
FORCING SO FAR TO THE NE OF THE CLOSED LO IN THE SRN PLAINS. A
SHRTWV TRACKING N INTO MN IS CAUSING A MORE WDSPRD AREA OF SHOWERS
IN THAT AREA.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS AND WINDS AS
UPR/SFC LO IN THE SRN PLAINS LIFTS TO THE N AND THRU MN ON WED.
ALTHOUGH THE UPR LO WL BE WEAKENING INTO WED AS THE DISTURBANCE
LIFTS TO THE N...THIS SHRTWV WL BEGIN PHASING THEN WITH ANOTHER
VIGOROUS DISTURBANCE MOVING INTO SCENTRAL CANADA.
TNGT...UPR LO IS FCST TO DRIFT SLOWLY TO THE N TO NEAR OMAHA BY 12Z
WED...WITH ASSOCIATED SFC LO NEAR 990MB MOVING INTO MN. ALTHOUGH
MODELS SHOW SLOWLY FALLING HGTS AND HINT A WAVE OR TWO OF UPR
DVGC/DEEP LYR QVECTOR CNVGC MAY SWING N THRU THE AREA ACCOMPANYING
RELATIVELY WEAK SHRTWVS WELL IN ADVANCE OF THE MAIN DISTURBANCE...
ABSENCE OF PERSISTENT SGNFT DYNAMIC FORCING AND SOME LINGERING LLVL
DRY AIR SHOULD LIMIT QPF...ESPECIALLY OVER THE E CLOSER TO THE DRY
AIR. LOOKS LIKE THE STRONGEST OF THESE DISTURBANCS WL IMPACT THE
AREA THIS EVNG. THE HEAVIEST RA SHOULD FALL OVER THE CENTRAL CWA
WHERE UPSLOPE SSE WINDS WL ACCENTUATE THE FORCING JUST TO THE W OF
THE DRIER LLVL AIR AND UNDER STRONGER H925 LLJ FLOW. WL GO WITH THE
HIEST CATEGORICAL POPS IN THIS AREA. DOWNSLOPING FLOW WL LIMIT
POPS/QPF OVER THE W. H925 WINDS WITHIN THE LLJ ARE FCST AS HI AS 40-
50KTS...BUT HIER STABILITY SHOWN ON FCST SDNGS UNDER THERMAL RDG WL
PREVENT THIS STRONG MOMENTUM FM MIXING TO THE SFC. STILL EXPECT
FREQUENT WIND GUSTS AS HI AS 30-35 MPH AT MORE EXPOSED LOCATIONS.
INFLUX OF DEEP MSTR/UPSLOPE LLVL FLOW WL SUPPORT SOME FOG MAINLY
OVER THE HIER TERRAIN OF THE CENTRAL. EXPECT LTL DIURNAL TEMP
DROP...IN FACT TEMPS MAY RISE SLOWLY AS THE STEADY SSE WINDS ADVECT
WARMER/HIER PWAT AIR INTO THE AREA.
WED...AS LO PRES TRACKS FM MN INTO NW ONTARIO DURING THE AFTN...THE
WEAKENING CLOSED LO IS FCST TO PHASE WITH ANOTHER SHRTWV MOVING THRU
SCENTRAL CANADA...RESULTING IN A DEEPENING LO PRES CENTER TO THE NW
IN THE AFTN. UPR MI WL BE DOMINATED BY THE STRONG SSW FLOW AND SOME
DRY SLOTTING ON THE SE FLANK OF THE LO. ALTHOUGH THERE COULD BE AN
AREA OF SHOWERS ACCOMPANYING THE PASSAGE OF AN OCCLUDED FNT/BAND OF
HIER MID LVL RH...THE OVERALL DRY SLOTTING AND DEEP LYR QVECTOR DVGC
PROGGED TO DOMINATE MUCH OF THE DAY WL LIMIT POPS AND QPF. FALLING
H85 TEMPS/SLOWLY DCRSG STABILITY IN THE AFTN AND APRCH OF PRES RISE
CENTER FM THE S MAY SUPPORT INCRSG SSW WIND GUSTS LATER IN THE DAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 335 PM EST TUE NOV 17 2015
...VERY WINDY ON THURSDAY...
LOW PRESSURE SUB 980MB LIFTING INTO NORTHWEST ONTARIO ON WEDNESDAY
EVENING ASSOCIATED WITH WEAKENING SOUTHERN STREAM SHORTWAVE LIFTING
INTO THE UPPER GREAT LAKES WILL DEEPEN TO SUB 970MB BY TIME IT
REACHES SOUTHWEST HUDSON BAY BY DAYBREAK ON THURSDAY. THIS DEEPENING
OF SFC LOW OCCURS AS SECONDARY SHORTWAVE TROUGH MOVING IN FROM THE
NORTHERN PLAINS PHASES WITH WEAKENING SOUTHERN STREAM SYSTEM. EXPECT
RAIN SHOWERS ON WEDNESDAY EVENING TO BE ISOLD IN COVERAGE DUE TO
WEAKENING UPPER LEVEL SYSTEM AND WEAK FORCING OVERALL. OVERNIGHT
WEDNESDAY NIGHT H85-H7 MOISTURE INCREASES ALONG WITH MID-LEVEL PVA
FM TROUGH NEARING FM THE NORTHERN PLAINS. SHOULD SEE SHOWERS INCREASE
BUT LACK OF DEEP MOISTURE INTO THE SYSTEM SHOULD PROHIBIT WIDESPREAD
PRECIPITATION. STRONG COLD FRONT SWEEPS EXTENDING TO THE SOUTH OF
THE LOW LIFTING INTO ONTARIO CROSSES WESTERN UPR MICHIGAN AROUND
MIDNIGHT WED NIGHT...CENTRAL UPR MICHIGAN LATE WED NIGHT TO AROUND
DAYBREAK ON THU...AND EASTERN UPR MICHIGAN LATE WED NIGHT THROUGH
THU MORNING. ANY RAIN SHOWERS SHOULD QUICKLY CHANGE TO SNOW SHOWERS
AS THE COLDER AIR ARRIVES. WINDS IN LOW-LEVELS STAY FM THE W-SW SO
ONLY LAKE EFFECT OF NOTE WOULD BE OCCURRING ON THE NORTHERN KEWEENAW
PENINSULA AND POSSIBLY ON FAR NORTHERN LAKE MICHIGAN MAINLY INTO
FAR EASTERN UPR MICHIGAN /APX CWA/.
BIG ISSUE WITH THIS SYSTEM DOES NOT APPEAR TO BE PRECIP OR SNOW /AT
LEAST INITIALLY/...BUT WINDS. ONCE THE COLD FRONT MOVES
THROUGH...NAM/GFS SOUNDINGS INDICATE WINDS ALOFT 30-45 KTS/UP TO
45MPH...STRONGEST OVER LK SUPERIOR AND THE KEWEENAW PENINSULA. DUE
TO THE COLD AIR ADVECTION AND UNSTABLE LOW-LEVEL TEMPERATURE
PROFILE...SOLID PORTION OF THESE WINDS SHOULD MIX TO SFC IN FREQUENT
GUSTS. GFS IS MORE ON THE HIGHER END IN TERMS OF STRENGTH OF WINDS
ALOFT...DUE TO STRONGER SFC LOW OVER HUDSON BAY COMPARED TO THE NAM.
GFS DOES LOOK SIMILAR TO ECMWF/GEM-NH IN PLACEMENT OF THE LOW ON THU
BUT SLIGHTLY STRONGER WITH INTENSITY. THUS...PROBABLY WILL NOT GO
COMPLETELY WITH GFS REALLY STRONG WINDS IDEA ATTM. RESULT WILL BE
ADVY SW WINDS NEAR LK SUPERIOR WEST...ESPECIALLY ON THE KEWEENAW.
WINDY BUT STAYING BLO ADVY ELSEWHERE. NO MATTER HOW YOU LOOK AT IT
THOUGH...A VERY WINDY AND MUCH COLDER DAY IN STORE ON THU.
SFC TROUGH CROSSES LK SUPERIOR AND UPR MICHIGAN ON THU NIGHT WITH
WINDS TURNING MORE W THAN SW. H85 TEMPS BY LATER THU NIGHT WILL BE
DOWN TO -12C OR LOWER. WITH WATER TEMPS AROUND 5-6C PER LATEST GLERL
ANALYSIS...OVER-WATER INSTABILITY IS MORE THAN SUFFICIENT FOR LAKE
EFFECT. WEST WINDS FAVOR KEWEENAW FOR MOST OF LAKE EFFECT SOUNDINGS
DO NOT LOOK PARTICULARY FAVORABLE THOUGH AS THEY SHOW INVERTED V
PROFILE WITH CLOUD BASE AROUND H85/3KFT EVEN DURING THU NIGHT INTO
FRI MORNING WHEN SHOULD SEE MORE MOISTENING IN LOWEST-LEVELS. LIKELY
TROUBLE IS WEST WINDS STAY 30-40KTS...CUTTING DOWN ON RESIDENCE TIME
AND EFFECTIVE OVER WATER FETCH. TYPICALLY WITH WINDS THIS
STRONG...THE LAKE EFFECT DOES NOT END UP TOO EXTENSIVE ON KEWEENAW
WHEN LACKING ADDITIONAL LARGE SCALE FORCING AND MOISTURE SEEN DURING
A LAKE ENHANCEMENT SETUP. CAVEAOT FOR POSSIBLY MORE LAKE EFECT COULD
BE IF AREA OF LOW-LEVEL CONVERGENCE DEVELOPS BTWN ONTONAGON AND
CALUMET AS SFC WINDS OVER WESTERN UPR MICHIGAN BECOME MORE WSW.
FAVORED TIME FOR THAT POTENTIAL WOULD BE THU NIGHT INTO FRI MORNING.
ANOTHER SHORTWAVE TROUGH IS FORECAST TO DIG INTO MEAN TROUGH OVER
MANTIOBA AND NORTHERN ONTARIO FRI NIGHT INTO SAT. THOUGH MAIN LARGE
SCALE FORCING AND ASSOCIATED PRECIP/MAINLY SNOW/ WITH THAT SHORTWAVE
LIKELY WILL STAY SOUTH FM THE CENTRAL PLAINS ON FRI TO THE OHIO
VALLEY/SOUTHERN GREAT LAKES FRI NIGHT INTO SAT...PASSAGE OF THE WAVE
WILL BRING WINDS TO MORE OF A NW DIRECTION. NW WINDS WITH H85 TEMPS
AT LEAST -12C IF NOT -15C AND MOISTURE TO INVERSION H8-H7/8-10KFT
AND WEAKENING WINDS SHOULD COMBINE TO INCREASE LES FOR AREAS FAVORED
BY NW FLOW. LOW-LEVEL WINDS STAYING CYCLONIC THROUGH THIS TIME ALSO
WITH SFC RIDGE OVER NORTHERN PLAINS AND SFC LOW DEEPENING OVER
CENTRAL GREAT LAKES. DEPENDING ON HOW FAR WEST THAT SFC LOW TRACKS
COULD SEE BRIEF PERIOD OF LES FOR N-NW FLOW AREAS AS WELL. WEAK LES
SHOULD PERSIST INTO SUN FOR NW WIND FAVORED AREAS. BY AFTN WINDS
BEGIN TO BECOME MORE W AND INVERSIONS FALL TO 3KFT...SO INTENSITY
SHOULD TAKE A BIT HIT. WINDS BECOME SW LATER SUN NIGHT INTO MONDAY
AND LES SHOULD FINISH UP AT THAT POINT.
UPPER LEVEL FLOW BY EARLY THANKSGIVING WEEK BECOMES MORE WNW-NW.
SERIES OF WEAKER UPPER LEVEL SYSTEMS WITH LIMITED MOISTURE AND WEAK
TROUGH PASSAGES ARE EXPECTED. WILL SEE TEMPS MODERATE COMPARED TO
THE CHILLY/BELOW NORMAL TEMPS THAT AFFECT THE AREA THU/FRI INTO THE
WEEKEND. LOOKING FARTHER AHEAD...APPEARS WARMER AND UNETTLED WEATHER
COULD SET UP INTO THANKSGIVING AS A LOW PRESSURE SYSTEMS AFFECTS
WESTERN GREAT LAKES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1257 PM EST TUE NOV 17 2015
FAIRLY COMPLEX AVIATION FCST IN THE SHORT TERM AS THERE IS A SHARP
GRADIENT OF LLVL MSTR ACRS THE AREA AS SHOWN ON THE 12Z GRB AND APX
RAOBS. EXPECT IMPROVING CONDITIONS THIS AFTN AT SAW AS A GUSTY LLVL
SE WIND TAPS SOME DRIER AIR NOW IN LOWER MI. MVFR CONDITIONS SHOULD
PERSIST AT IWD AND CMX FARTHER FM THE DRY AIR SOURCE. AN AREA OF
MOISTER LLVL AIR AND SHOWERS WL ARRIVE TNGT...ALLOWING FOR IFR
CONDITIONS TO PREDOMINATE AT SAW. DOWNSLOPE NATURE OF THE LLVL FLOW
MAKES THE FCST A BIT MORE DIFFICULT FOR IWD AND CMX AND MAY RESULT
IN MORE PERSISTENT MVFR CONDITIONS. ALTHOUGH WINDS WL BE GUSTY UNDER
A S LLJ THAT WL BE STRONGEST OVER SAW...ADDED LLWS TO THE FCST FOR
THAT LOCATION GIVEN HI STABILITY UNDER THE AXIS OF STRONGEST WINDS
THAT WL MITIGATE MIXING. GUSTY S WINDS AND MVFR CONDITIONS WL THEN
BE THE RULE AT IWD AND CMX BY LATE WED MRNG...BUT CONTINUED UPSLOPE
WIND COMPONENT INTO SAW WL LIKELY HOLD CIGS IN THE IFR RANGE THERE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 335 PM EST TUE NOV 17 2015
A TIGHT PRES GRADIENT BETWEEN A LO PRES CENTER MOVING N THRU THE MS
RIVER VALLEY AND A HI PRES CENTER OVER THE CANADIAN MARITIMES WILL
RESULT IN SSE GALES TO 35-40 KTS OVER THE NCENTRAL AND EASTERN
PORTIONS OF THE LAKE THRU WED. A WEAKER GRADIENT CLOSER TO THE LO
TRACK AND INFLUENCE OF TERRAIN WILL HOLD WINDS OVER THE WESTERN
PORTION OF THE LAKE UNDER GALE FORCE. LOW PRESSURE SYSTEM DEEPENS AS
IT LIFTS INTO NORTHERN ONTARIO WED NIGHT INTO THURSDAY AND STAYS
STATIONARY OVER HUDSON BAY INTO FRIDAY. SE GALES AHEAD OF THE LOW
SHIFT TO THE WSW-W ON THU BEHIND STRONG COLD FRONT. EXPECT SOLID
GALE FORCE WINDS ACROSS LK SUPERIOR WITH POTENTIAL FOR STORM FORCE
GUSTS THU AFTN INTO THU EVENING OVER CNTRL LK SUPERIOR AS TROUGH
CROSSES. WILL NOT ISSUE A STORM WATCH ATTM AS STORM FORCE WINDS
WOULD ONLY BE AROUND 3 HR IN DURATION AND NOT TOO WIDESPREAD. LATER
FORECASTS MAY NEED TO ISSUE STORM WATCH IF EXPECTATIONS ON WINDS
CHANGE.
WINDS DIMINISH INTO FRIDAY AS PRESSURE GRADIENT RELAXES...BUT LIKELY
WILL REMAIN AT GALE FORCE UNTIL FRIDAY NIGHT FOR EASTERN SECTIONS.
WINDS WEAKEN FURTHER BLO 25 KTS THROUGH THE WEEKEND AS HIGH PRESSURE
RIDGE SLOWLY CROSSES THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THIS EVENING TO 7 PM EST WEDNESDAY FOR
LSZ264-266-267.
GALE WARNING FROM 7 PM THIS EVENING TO 2 AM EST WEDNESDAY FOR
LSZ244-245.
GALE WARNING FROM 7 PM THIS EVENING TO 7 AM EST WEDNESDAY FOR
LSZ251.
LAKE MICHIGAN...
GALE WARNING FROM 7 AM WEDNESDAY TO 6 PM EST THURSDAY FOR LMZ221-
248-250.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS GAYLORD MI
337 PM EST TUE NOV 17 2015
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 337 PM EST TUE NOV 17 2015
SE LOW LEVEL FLOW CONTINUES TO STRENGTHEN LATE THIS AFTERNOON WELL
IN ADVANCE OF LOW PRESSURE DEVELOPING OVER THE SRN PLAINS. LOW AND
MID LEVEL MOISTURE IS GRADUALLY INCREASING ACROSS THE WRN GREAT
LAKES REGION WITHIN MOIST WAA PATTERN. GULF IS WIDE OPEN AHEAD OF
THIS DEVELOPING SYSTEM...TAPPING INTO DEEP MOISTURE WHICH WILL
CONTINUE TO SURGE NORTHWARD LATE THIS AFTERNOON AND INTO THIS
EVENING. REGIONAL MOSAIC RADAR CONTINUES TO TELL THE TALE...SHOWING
WIDESPREAD CONVECTION DEVELOPING FROM ERN TEXAS THRU MISSOURI...
ILLINOIS AND INDIANA NORTHWARD INTO IOWA AND MINNESOTA. WISCONSIN
HAS BEGUN TO GET IN ON THE ACTION...WITH THE LEADING EDGE OF
WIDESPREAD PRECIP NOW THRU MUCH OF SRN AND WRN WISCONSIN. THIS
LEADING EDGE WILL PUSH NE INTO OUR CWA LATE THIS AFTERNOON AND EARLY
THIS EVENING.
DRY AIR CURRENTLY IN PLACE AND RATHER DRY SE LOW LEVEL FLOW HAS
TENDED TO ERODE THE LEADING EDGE OF THE PRECIP SHIELD AS IT TRIES TO
PUSH NE INTO OUR CWA. PERSISTENT DRY AIR OVERHEAD WILL FINALLY GIVE
WAY TO WIDESPREAD PRECIP PUSHING INTO OUR REGION FROM SW TO NE THRU
EARLY EVENING. NAM12...RAP13 AND HRRR ALL SUGGEST HIGHEST POPS WILL
BE ACROSS WRN SECTIONS OF OUR CWA WHERE DEEPEST MOISTURE WILL SURGE
NORTHWARD AHEAD OF THE LOW CENTER. ALL MODELS ALSO STILL SUGGEST A
LULL IN THE ACTION OVERNIGHT AS A SURGE OF DRIER AIR PUSHES THRU LWR
MICHIGAN. AGAIN...HIGHEST POPS OVERNIGHT WILL REMAIN WEST AS WELL AS
ACROSS ERN UPR MICHIGAN WHERE THE ERN EDGE OF THE DEEPER MOISTURE
WILL HOLD ON. HAVE MADE SOME MINOR CHANGES TO POP FORECAST FOR
TONIGHT...INCLUDING TIMING AND AMOUNT. BUT OVERALL FLAVOR OF THE
FORECAST REMAINS...WITH HIGHEST POPS WEST AND A SIGNIFICANT DIMINISH
IN POPS OVERNIGHT. CERTAINLY NO PRECIP TYPE ISSUES WITH PLENTY OF
WARM AIR SURGING NORTHWARD AHEAD OF THE LOW. OVERNIGHT LOWS WILL
GENERALLY BE IN THE 40S.
GUSTY SE WINDS WILL CONTINUE...AND WILL ACTUALLY FURTHER STRENGTHEN
OVERNIGHT AS PRESSURE GRADIENT TIGHTENS AS THE LOW LISTS INTO
MINNESOTA. EXPECT GUSTS OF 20 TO 30 MPH...WITH A FEW HIGHER GUSTS
POSSIBLE. AT THIS TIME...DO NOT EXPECT ANY PART OF OUR CWA TO REACH
WIND ADVISORY CRITERIA.
&&
.SHORT TERM...(WEDNESDAY THROUGH FRIDAY)
ISSUED AT 337 PM EST TUE NOV 17 2015
HIGH IMPACT WEATHER POTENTIAL: GALE CONCERNS ON THE BIG WATERS.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: BIG CHANGES...WITH MORE
REALISTIC NOVEMBER WEATHER SET TO RETURN BY THE END OF THIS WEEK.
IMPETUS BEHIND SUCH CHANGES IS DEEP SOUTHERN STREAM WAVE ROTATING
THROUGH THE CENTRAL PLAINS. THIS SYSTEM...ALONG WITH NORTHERN STREAM
ENERGY DIGGING IN BEHIND IT...WILL PLOW A RATHER STRONG COLD FRONT
AND ATTENDANT WIND/RAIN EVENT THROUGH OUR AREA WEDNESDAY AND
WEDNESDAY NIGHT. INITIAL POST FRONTAL SURGE OF CAA IS NOT TOO
TERRIBLY IMPRESSIVE BY NOVEMBER STANDARDS. HOWEVER...AS NORTHERN
ENERGY AND SECONDARY COLD FRONT BECOME INCREASINGLY INVOLVED BY
FRIDAY...WOULD EXPECT CONDITIONS TO HAVE A MUCH MORE WINTRY FEEL TO
THEM (AND PERHAPS SETTING THE STAGE FOR SOME ACCUMULATING SNOW FOR
THE WEEKEND...SEE LONG TERM SECTION BELOW FOR THOSE DETAILS).
PRIMARY FORECAST CONCERNS/CHALLENGES: PRECIPITATION EVOLUTION
(COVERAGE/TIMING/TYPE) AND WIND IMPACTS RIGHT THROUGH THE FORECAST.
DETAILS: LAST WARM DAY WEDNESDAY (AT LEAST FOR A WHILE) AS AREA
REMAINS IS DEEP SOUTH FLOW WILL OUT AHEAD OF DEEPENING MINNESOTA LOW
PRESSURE AND APPROACHING OCCLUDED FRONT. MOISTURE PROFILES RATHER
REMARKABLE...UP NEAR 1.25 INCHES...WHICH IS IN RECORD SETTING
TERRITORY FOR THIS TIME OF YEAR. DESPITE IMPRESSIVE WAVE OPENING UP
JUST TO OUR WEST...OVERALL FORCING AND MOISTURE AXIS BECOMES
INCREASINGLY STRUNG OUT THROUGH THE DAY...WITH TWO CENTERS OF
HEAVIEST RAINS...ONE OFF TO OUR NORTHWEST COLLOCATED WITH BEST MID
LEVEL SUPPORT...AND ONE WELL OFF TO OUR SOUTH IN VICINITY OF RER
UPPER JET DYNAMICS AND BETTER FORCED LOWER LEVEL CONVERGENCE.
NOW...WITH ALL THAT SAID...SHOWERS WILL OCCUR WEDNESDAY INTO
WEDNESDAY EVENING AS OCCLUDED FRONT WORKS OVER OVERHEAD MOIST
AIRMASS...BUT JUST NOT SEEING ANY INDICATIONS OF SIGNIFICANT RAINS
(DESPITE THE RECORD AVAILABLE MOISTURE). OTHER STORY WILL BE FAIRLY
GUSTY SOUTHEAST WINDS WITH OVERHEAD GRADIENT AND BUFKIT DOWNWARD
MOMENTUM TRANSFER SHOWING SUSTAINED WINDS OF 15 TO 20 MPH...WITH
GUSTS AOA 30.
OCCLUDED FRONT PASSES WEDNESDAY EVENING...WITH AGGRESSIVE MID LEVEL
DRY SLOT ENDING WIDESPREAD SHOWERS QUICKLY FROM WEST TO EAST.
INITIAL POST-FRONT AIRMASS LOOKS A TOUCH TOO WARM FOR ANY LAKE
CONTRIBUTION...ALTHOUGH MAY SEE SOME ADDITIONAL SCATTERED LIGHT
SHOWER DEVELOPMENT AS PRIMARY COLD FRONT MAKES A RUN THROUGH THE
WESTERN LAKES BY THURSDAY MORNING. THIS INITIAL SHOT OF CAA DOES SET
THE STAGE FOR SOME VERY WINDY CONDITIONS...ESPECIALLY OVER NORTHERN
LAKE MICHIGAN AND ADJACENT SHORELINE AREAS. NAM-WRF PARTICULARLY
ROBUST...SHOWING NICE LOW LEVEL JET CORE OF 45 KNOTS...AND GOOD
PORTION OF WHICH IS ABLE TO MIX TO THE SURFACE. GALES LOOK A
CERTAINTY (SEE MARINE DISCUSSION BELOW)...AND DO HAVE SOME CONCERN
FOR LOW END WIND ADVISORY GUSTS...ESPECIALLY FOR THE MACKINAC COUNTY
SHORELINE ALONG LAKE MICHIGAN AND THE IMMEDIATE COAST OF NORTHWEST
LOWER MICHIGAN. TOO EARLY WITH TOO MUCH LINGERING UNCERTAINTY FOR
ANY TYPE OF ADVISORY HEADLINE...BUT SOMETHING TO WATCH FOR SURE.
PROGRESSIVELY COLDER AIR FILTERS INTO THE REGION THURSDAY AND FRIDAY
AS GUSTY SOUTHWEST WINDS CONTINUE. TEMPERATURES DEFINITELY TREND
COLD ENOUGH (H8 TEMPS FALLING TO THE NEGATIVE UPPER SINGLE DIGITS
LATER THURSDAY THROUGH FRIDAY) FOR SOME LAKE MOISTURE CONTRIBUTION
TO OCCUR...ESPECIALLY TARGETING THOSE AREAS FAVORED BY SOUTHWEST
WINDS. SYNOPTIC MOISTURE PROFILES NOT OVERLY IMPRESSIVE...WITH
BETTER MOISTURE CONFINED TO LAKE SUPERIOR AND POINTS NORTH. INITIAL
RAIN/SNOW MIX WILL TREND TOWARDS ALL SNOW BY LATER THURSDAY AND
FRIDAY. SURFACE TEMPERATURES WILL REMAIN MARGINAL FOR SNOW TO
ACCUMULATE...WITH FLOW TRAJECTORIES NOT TARGETING THE INTERIOR
COLDER HIGHLANDS. STILL...SUPPOSE SOME SLUSHY SNOW ACCUMULATIONS
WILL BE POSSIBLE FOR THE TIP OF THE MITT AND UP INTO THE STRAITS
REGION OF EASTERN UPPER.
&&
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 337 PM EST TUE NOV 17 2015
EARLY IN THE PERIOD...FOCUS REVOLVES AROUND AN INCOMING WAVE FROM
THE PLAINS...POTENTIALLY BRINGING A WIDESPREAD SNOW EVENT TO THE
MIDWEST/GREAT LAKES. WILL START BY MENTIONING THAT THERE IS A HIGH
DEGREE OF UNCERTAINTY DURING THE FRIDAY NIGHT - SUNDAY TIMEFRAME AS
GUIDANCE CONTINUES TO WAFFLE BACK AND FORTH ON SOLUTIONS. WILL GO
AHEAD AND COVER SEVERAL FEASIBLE SOLUTIONS AT THIS POINT...BUT FULLY
EXPECT SEVERAL MORE FLIP-FLOPS UNTIL AFTER THE WAVE STARTS GETTING
SAMPLED AFTER IT MAKES ITS WAY ON LAND FROM THE PACIFIC.
TWO DISTINCT POSSIBILITIES COULD POTENTIALLY PLAY OUT AT THIS POINT.
SCENARIO 1 FOLLOWS ALONG THE LINES OF THE 17/12Z GFS AND THE 17/12Z
ECMWF. THE INITIAL STORM SYSTEM AFFECTING THE AREA THROUGH THURSDAY
RATHER QUICKLY SHIFTS NORTH AND EAST...ALLOWING FOR HEIGHTS TO
REBOUND AHEAD OF THE NEXT WAVE. IN COMBINATION WITH DEEP TROUGHING
EXPECTED TO SURGE OUT OF CANADA INTO THE NORTHERN TIER OF THE
CONUS...THIS SOLUTION ALLOWS THE SYSTEM TO AMPLIFY AS IT MOVES
THROUGH IL/SOUTHERN MI BRINGING A DEEPENING SFC LOW THROUGH SRN
MI/THUMB IN WHAT COULD POTENTIALLY PLAY OUT AS A SNOWY WEEKEND
ACROSS PARTS OF NRN LOWER MI.
SCENARIO 2...MORE IN LINE WITH THE 17/12Z GEM...17/12Z UKMET AND
MANY 06Z & 12Z ENSEMBLE MEMBERS...LAGS THE DEPARTURE OF THE INITIAL
SYSTEM RESULTING IN ENERGY SHEARING OUT ACROSS THE UPPER MS VALLEY
WITH THE SFC LOW TRAVELING THROUGH THE OHIO VALLEY AND A NEAR TO
COMPLETE MISS FOR SYNOPTIC SNOWFALL ACROSS NRN MI.
BEYOND SUNDAY...COULD SEE BOUTS OF LIGHT LAKE EFFECT SNOW ACROSS
TYPICAL AREAS AND PERHAPS ANOTHER WEAK WAVE OR TWO (WITH ASSOCIATED
LIGHT PRECIP) SLIDING THROUGH WHAT GRADUALLY BECOMES MORE ZONAL FLOW
ACROSS THE HEART OF THE COUNTRY THROUGH MIDWEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1233 PM EST TUE NOV 17 2015
DEEPENING LOW PRESSURE WILL LIFT NORTHWARD THRU THE PLAINS INTO
MINNESOTA TONIGHT INTO WEDNESDAY...WITH DEEP MOISTURE SURGING INTO
THE WRN GREAT LAKES OUT AHEAD OF THIS SYSTEM. CIGS WILL LOWER TO
MVFR FROM SW TO NE DURING LATE AFTERNOON AND EARLY EVENING AS
WIDESPREAD RAIN SPREADS INTO NRN LWR MICHIGAN. VSBYS WILL ALSO
LOWER TO PREVAILING MVFR WITHIN THIS AREA OF STEADY RAIN. THIS
INITIAL WAVE TO RAIN WILL DIMINISH OVERNIGHT INTO EARLY WEDNESDAY
BEFORE ANOTHER WAVE OF RAIN ARRIVES WEDNESDAY AFTERNOON. LLWS WILL
DEVELOP LATE TONIGHT INTO WEDNESDAY AS WINDS FURTHER STRENGTHEN
ALOFT. SURFACE WINDS WILL GUST FROM THE SE UP TO 30 KTS.
&&
.MARINE...
ISSUED AT 337 PM EST TUE NOV 17 2015
GALE FORCE WINDS AND HIGH WAVES WILL DEVELOP FOR ALL NEARSHORE AREAS
BY WEDNESDAY AS DEEP LOW PRESSURE LIFTS NE THRU THE MISSISSIPPI
VALLEY...PRODUCING A TIGHT LOW LEVEL PRESSURE GRADIENT ACROSS THE
WRN GREAT LAKES REGION. WAVES OF WIDESPREAD RAIN WILL ALSO DEVELOP
AHEAD OF THE LOW...IMPACTING ALL NEARSHORE AREAS TONIGHT AND
WEDNESDAY.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...GALE WARNING FROM 10 AM TO 11 PM EST WEDNESDAY FOR LHZ345>349.
LM...GALE WARNING FROM 10 AM WEDNESDAY TO 7 PM EST THURSDAY FOR
LMZ323-341-342-344>346.
LS...GALE WARNING FROM 10 AM TO 11 PM EST WEDNESDAY FOR LSZ322.
GALE WARNING UNTIL 7 PM EST WEDNESDAY FOR LSZ321.
&&
$$
NEAR TERM...MLR
SHORT TERM...MSB
LONG TERM...GILLEN
AVIATION...MLR
MARINE...MLR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
327 AM EST TUE NOV 17 2015
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY EVENING)
ISSUED AT 346 PM EST MON NOV 16 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SERIES
OF SHORTWAVES IN THE SOUTHWEST FLOW ALOFT...FROM NORTHERN
MINNESOTA TO IOWA EARLY THIS AFTERNOON. SHOWER ACTIVITY IS
WIDESPREAD AHEAD OF THESE SHORTWAVES OVER WESTERN WISCONSIN AND
NORTHERN MINNESOTA. SPOTTIER SHOWERS ARE DEVELOPING AHEAD OF THIS
BAND OF RAIN WHICH ARE MOVING OVER WESTERN LAKE SUPERIOR AND
APPROACHING THE FAR WESTERN UPPER PENINSULA. OTHERWISE...SKIES ARE
PARTLY TO MOSTLY CLOUDY ACROSS THE U.P. WITH TEMPERATURES WELL
ABOVE NORMAL. FORECAST CONCERNS INCLUDE PRECIPITATION TRENDS
FOLLOWED BY MARINE ISSUES.
TONIGHT...SHORTWAVE ENERGY WILL MOVE NORTHEAST OVER FAR WESTERN
LAKE SUPERIOR AND WESTERN ONTARIO THIS EVENING. PASSAGE OF THIS
SHORTWAVE AND ASSOCIATED MOISTURE TRANSPORT WILL BRING PERIODS OF
RAIN TO WESTERN LAKE SUPERIOR AND THE WESTERN UPPER PENINSULA
DURING THE EVENING. THE SHOWERS SHOULD BECOME MORE SPOTTY
OVERNIGHT AS THE STRONGER FORCING DEPARTS TO THE NORTH AND
MOISTURE ADVECTION WEAKENS. THE PRECIPITATION WILL PROBABLY NOT
MAKE IT INTO THE EASTERN SECTIONS OF THE UPPER PENINSULA THOUGH.
SOUTHEAST WINDS CIRCULATING AROUND A STRONG SURFACE HIGH OVER
QUEBEC WILL KEEP A FEED OF DRY LOW TO MID-LEVEL AIR IN THIS
PORTION OF THE STATE. OTHERWISE...MOSTLY CLOUDY TO CLOUDY
CONDITIONS SHOULD PREVAIL. WITH A BREEZY SOUTHEAST WIND...LOWS TO
FALL INTO THE LOW TO MID 40S.
TUESDAY...A COLD FRONT WILL CONTINUE TO SLOWLY WORK EAST ACROSS
THE NORTHERN PLAINS WHILE LOW PRESSURE STRENGTHENS FURTHER SOUTH.
AHEAD OF THESE FEATURES...SOUTH TO SOUTHEAST WINDS ALOFT WILL
BOOST PWATS THROUGH THE DAY. SPOTTY SHOWERS WILL LIKELY CONTINUE
OVER THE WESTERN HALF OF THE UPPER PENINSULA DURING THE MORNING IN
A WEAK ISENTROPIC ASCENT REGIME. THEN THE NAM/GFS BRING IN SHORTWAVE
ENERGY INTO THE REGION DURING THE AFTERNOON. ISENTROPIC ASCENT
STRENGTHENS DURING THIS TIME...WHICH ARGUES FOR HIGHER COVERAGE OF
SHOWER ACTIVITY. WITH CLOUDY CONDITIONS AND BREEZY SOUTHEAST
WINDS...HIGHS TO REACH INTO THE UPPER 40S TO LOW 50S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 326 AM EST TUE NOV 17 2015
A DEEPENING LOW PRESSURE SYSTEM LOCATED IN CENTRAL MINNESOTA WILL
BE QUICKLY LIFTING NORTH INTO NORTHWEST ONTARIO ON
WEDNESDAY INTO WEDNESDAY NIGHT...INTENSIFYING FROM 986MB AT 12Z
WEDNESDAY TO 969MB BY 06Z THURSDAY...AS IT PHASES WITH A SECONDARY
SHORTWAVE DROPPING SOUTHEAST FROM BRITISH COLUMBIA. THIS RAPID
INTENSIFICATION WILL SET THE STAGE FOR A WINDY SECOND HALF OF THE
WORK WEEK ACROSS THE U.P.. BEFORE THE WIND ARRIVES...ABUNDANT
MOISTURE SURGING NORTH AHEAD OF THE LOW WILL LEAD TO SCATTERED TO
NUMEROUS RAIN SHOWERS ON WEDNESDAY INTO WEDNESDAY EVENING WITH THE
FIRST SHORTWAVE LIFTING NORTH ACROSS THE AREA. AN INVERSION SETUP BY
THE WARM AIR ADVECTION ABOVE 925MB WILL KEEP THE WINDS IN CHECK ON
WEDNESDAY...BUT STILL EXPECT TO SEE SOME GUSTS AROUND 25KTS AND
MAYBE A FEW GUSTS TO 30-35KTS OVER THE EASTERN U.P.. WEDNESDAY WILL
BE THE LAST DAY OF ABOVE NORMAL TEMPERATURES FOR A WHILE (AT LEAST
THROUGH THE WEEKEND).
AS THOSE SHOWERS DEPART...A COLD FRONT WILL SWEEP WEST
ACROSS THE AREA ON WEDNESDAY NIGHT...BRINGING MUCH COLDER AIR TO
THE AREA FOR THE REST OF THE LONG TERM FORECAST. THERE MAY BE SOME
SHOWERS (TRANSITIONING TO SNOW) ALONG AND BEHIND THE COLD FRONT AS
THE COLD AIR SURGES INTO THE AREA AND THE SECONDARY SHORTWAVE (FROM
BRITISH COLUMBIA) MOVES THROUGH THE U.P. THROUGH EARLY THURSDAY
AFTERNOON...BUT THE MAIN STORY WILL BE THE WINDS. MODELS HAVE
CONTINUED TO SHIFT THE WINDS MORE TO THE SOUTHWEST...LIKELY
LIMITING LAKE EFFECT POTENTIAL OVER THE KEWEENAW ON THURSDAY (ALONG
WITH THE WELL MIXED BOUNDARY LAYER). THUS...THE WINDS WILL BE THE
MAIN STORY AND IT CONTINUES TO LOOK LIKE A GREAT SETUP (DEEPENING
LOW...TIGHT PRESSURE GRADIENT...STRONG COLD AIR ADVECTION ACROSS THE
RELATIVELY WARM LAKE SUPERIOR WATERS) FOR AT LEAST WIND ADVISORY
WINDS FOR THE KEWEENAW AND POSSIBLY SOME THE OTHER SHORELINE AREAS
OF THE WESTERN U.P.. WILL CONTINUE TO SHOW HIGH END WIND
ADVISORY...BUT THINK THE KEWEENAW COULD BE NEARING HIGH WIND WARNING
VALUES TOWARDS THURSDAY EVENING (BETWEEN 21-00Z) AS A SECONDARY
TROUGH DROPS SLIDES EAST ACROSS NORTHERN ONTARIO AND BRUSHES THAT
AREA WITH STRONGER PRESSURE RISES AS WINDS TURN TO THE WEST. ONCE
THAT TROUGH MOVES THROUGH ON THURSDAY EVENING...WINDS WILL SHIFT TO
THE WEST AND GRADUALLY DECREASE THROUGH FRIDAY.
THAT WESTWARD SHIFT IN THE WINDS WILL BRING A BETTER LAKE EFFECT
SNOW SETUP TO THE AREA FOR THURSDAY NIGHT INTO THE START OF THE
WEEKEND. 850MB TEMPS WILL FALL FROM -8C AHEAD OF THE TROUGH ON
THURSDAY TO -12C BY MID DAY FRIDAY. IN ADDITION...THE LOW LEVEL
MOISTURE PROFILE WILL IMPROVE...LOWERING CEILINGS TOWARDS 3KFT VS
THE 4-5KFT AHEAD OF THE TROUGH. WITH THE STEEP LOW LEVEL LAPSE
RATES AND INVERSION HEIGHTS AROUND 10KFT...THE POTENTIAL FOR
MODERATE TO HEAVY SNOW IS THERE...BUT THINK THE WINDS (STILL
35-40KTS OVERNIGHT THURSDAY) WILL LIMIT RESIDENCE TIME OVER THE
WESTERN LAKE AND ALSO FRACTURE THE FLAKES AS THEY FALL (KEEPING
RATIOS LOWER THAN WHAT WOULD NORMALLY BE EXPECTED IN LAKE EFFECT).
THUS...NOT EXPECTING SIGNIFICANT LAKE EFFECT SNOW OVER THE KEWEENAW
BUT THE COMBINATION OF GUSTY WINDS AND SMALL FLAKES WILL LEAD TO
GREATLY REDUCED VISIBILITIES AT TIMES THURSDAY NIGHT INTO FRIDAY.
ALSO FOR FRIDAY...INVERSION HEIGHTS FALL TO THE 6 TO MAYBE 8KFT
RANGE...WHICH WILL START TO INHIBIT THE CLOUD DEPTH FOR STRONGER
LAKE EFFECT WITH BASES STILL LOOKING TO BE AROUND 3KFT.
HEADING INTO THE WEEKEND...MODELS STILL STRUGGLING WITH THE
EVOLUTION OF ANOTHER UPPER TROUGH DROPPING SOUTHEAST FROM THE
CANADIAN ROCKIES ON FRIDAY AND THROUGH THE GREAT LAKES REGION
DURING THE WEEKEND. THEIR DIFFERENCES ARE TIED TO THE STRENGTH AND
HOW WRAPPED UP THE UPPER TROUGH WILL BECOME AS IT MOVES THROUGH THE
REGION...LEADING TO DIFFERENCES IN THE SURFACE FEATURES. THE 00Z
GFS MAINTAINS ITS CONSISTENT IDEA OF A LOW DEVELOPING IN THE OHIO
RIVER VALLEY AND LIFTING THROUGH THE EASTERN GREAT LAKES ON
SATURDAY. THIS IDEA HAS BEEN TRENDED TOWARDS WITH THE GEM AND
00Z ECMWF. LOOKING AT THE BIG 3 ENSEMBLE MEMBERS...ONLY SEE LIMITED
SUPPORT OF THE DETERMINISTIC 00Z GFS/GEM/ECMWF SOLUTIONS WHICH LEADS
TO LOW CONFIDENCE IN THAT STRONGER SOLUTION. WHILE THE MAIN
PRECIPITATION WITH THE LOW WILL BE TO THE EAST OF THE
AREA...TEMPERATURES ALOFT WILL BE AROUND -12 TO -14C AND WITH
GENERALLY NORTHWEST TO NORTHERLY FLOW...EXPECT LAKE EFFECT SNOW TO
CONTINUE THROUGH MUCH OF THE WEEKEND. IT IS STILL A WAYS OUT AND
DEALING WITH COARSER MODELS (TO GET TOO GOOD OF A HANDLE ON THE
MOISTURE FIELDS)...BUT THE SETUP COULD BE DECENT FOR MODERATE LAKE
EFFECT SNOW FOR THE FAVORED NORTHWEST TO NORTHERLY LAKE EFFECT SNOW
BELTS FOR THE FIRST HALF OF THE WEEKEND. THE UPPER TROUGH WILL
DEPART SUNDAY INTO MONDAY...LEADING TO A WARMING TREND AND
DIMINISHING LAKE EFFECT POTENTIAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1200 AM EST TUE NOV 17 2015
INCREASING LOW-LEVEL MOISTURE AHEAD OF LOW PRES ORGANIZING OVER THE
PLAINS WILL LEAD TO AN OVERALL GRADUAL DETERIORATION OF CONDITIONS
DURING THIS FCST PERIOD. AT ALL TERMINALS...PERSISTENT LOW-LEVEL JET
OVER THE AREA WILL RESULT IN LLWS FOR MUCH OF THE PERIOD...
ESPECIALLY AT KCMX WHERE THERE WILL BE MORE OF A DIRECTIONAL CHANGE
OF WIND IN THE SHEAR LAYER. OTHERWISE...MVFR CONDITIONS AT KIWD WILL
SPREAD TO KCMX LATER IN THE NIGHT AND TO KSAW THIS MORNING. WITH
SHOWER COVERAGE INCREASING DURING THE AFTN AND EVENING...IFR OR EVEN
LIFR CONDITIONS WILL DEVELOP WITH THE LOWEST CONDITIONS AT KSAW DUE
TO MORE FAVORABLE UPSLOPE FLOW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED
AT 346 PM EST MON NOV 16 2015
A TIGHT PRESSURE GRADIENT WILL BE IN PLACE ACROSS THE REGION
BETWEEN HIGH PRESSURE OVER QUEBEC AND A TROUGH OF LOW PRESSURE
MOVING SLOWLY OVER THE PLAINS THROUGH WEDNESDAY. THIS TIGHT
PRESSURE GRADIENT WILL BRING A PROLONGED PERIOD OF GUSTY SOUTH TO
SOUTHEAST WINDS. SHORELINES EXPOSED TO WINDS FROM THESE DIRECTIONS WILL
SEE WAVES GREATER THAN 4 FEET DEVELOP...WHERE SMALL CRAFT
ADVISORIES ARE IN EFFECT. IN ADDITION...EASTERN PORTIONS OF LAKE
SUPERIOR CLOSER TO THE CANADIAN WATERS WILL SEE NEAR GALE FORCE
GUSTS AT TIMES. CONDITIONS LOOK A LITTLE TOO STABLE FOR WIDESPREAD
GALES TO OCCUR HOWEVER.
THEN A STRONG COLD FRONT WILL MOVE ACROSS THE REGION WEDNESDAY
NIGHT INTO THURSDAY. BEHIND THE FRONT...WIDESPREAD GALES ARE
LIKELY. NEAR STORM FORCE GUSTS WILL BE POSSIBLE OVER THE WESTERN
HALF OF LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SL/MPC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...MPC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1201 AM EST TUE NOV 17 2015
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY EVENING)
ISSUED AT 346 PM EST MON NOV 16 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SERIES
OF SHORTWAVES IN THE SOUTHWEST FLOW ALOFT...FROM NORTHERN
MINNESOTA TO IOWA EARLY THIS AFTERNOON. SHOWER ACTIVITY IS
WIDESPREAD AHEAD OF THESE SHORTWAVES OVER WESTERN WISCONSIN AND
NORTHERN MINNESOTA. SPOTTIER SHOWERS ARE DEVELOPING AHEAD OF THIS
BAND OF RAIN WHICH ARE MOVING OVER WESTERN LAKE SUPERIOR AND
APPROACHING THE FAR WESTERN UPPER PENINSULA. OTHERWISE...SKIES ARE
PARTLY TO MOSTLY CLOUDY ACROSS THE U.P. WITH TEMPERATURES WELL
ABOVE NORMAL. FORECAST CONCERNS INCLUDE PRECIPITATION TRENDS
FOLLOWED BY MARINE ISSUES.
TONIGHT...SHORTWAVE ENERGY WILL MOVE NORTHEAST OVER FAR WESTERN
LAKE SUPERIOR AND WESTERN ONTARIO THIS EVENING. PASSAGE OF THIS
SHORTWAVE AND ASSOCIATED MOISTURE TRANSPORT WILL BRING PERIODS OF
RAIN TO WESTERN LAKE SUPERIOR AND THE WESTERN UPPER PENINSULA
DURING THE EVENING. THE SHOWERS SHOULD BECOME MORE SPOTTY
OVERNIGHT AS THE STRONGER FORCING DEPARTS TO THE NORTH AND
MOISTURE ADVECTION WEAKENS. THE PRECIPITATION WILL PROBABLY NOT
MAKE IT INTO THE EASTERN SECTIONS OF THE UPPER PENINSULA THOUGH.
SOUTHEAST WINDS CIRCULATING AROUND A STRONG SURFACE HIGH OVER
QUEBEC WILL KEEP A FEED OF DRY LOW TO MID-LEVEL AIR IN THIS
PORTION OF THE STATE. OTHERWISE...MOSTLY CLOUDY TO CLOUDY
CONDITIONS SHOULD PREVAIL. WITH A BREEZY SOUTHEAST WIND...LOWS TO
FALL INTO THE LOW TO MID 40S.
TUESDAY...A COLD FRONT WILL CONTINUE TO SLOWLY WORK EAST ACROSS
THE NORTHERN PLAINS WHILE LOW PRESSURE STRENGTHENS FURTHER SOUTH.
AHEAD OF THESE FEATURES...SOUTH TO SOUTHEAST WINDS ALOFT WILL
BOOST PWATS THROUGH THE DAY. SPOTTY SHOWERS WILL LIKELY CONTINUE
OVER THE WESTERN HALF OF THE UPPER PENINSULA DURING THE MORNING IN
A WEAK ISENTROPIC ASCENT REGIME. THEN THE NAM/GFS BRING IN SHORTWAVE
ENERGY INTO THE REGION DURING THE AFTERNOON. ISENTROPIC ASCENT
STRENGTHENS DURING THIS TIME...WHICH ARGUES FOR HIGHER COVERAGE OF
SHOWER ACTIVITY. WITH CLOUDY CONDITIONS AND BREEZY SOUTHEAST
WINDS...HIGHS TO REACH INTO THE UPPER 40S TO LOW 50S.
.LONG TERM...(AFTER MIDNIGHT TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 346 PM EST MON NOV 16 2015
STRONG UPPER LOW WILL MOVE FORM KANSAS TOWARDS WISCONSIN AND
BEGIN TO PHASE WITH A VERY STRONG UPPER TROUGH DIVING SOUTHEAST
TO THE NORTHERN PLAINS. THERE ARE SOME MODEL DIFFERENCES WITH THE
EXTENT TO WITH PHASING OCCURS AND HOW QUICKLY. THIS ALSO EFFECT
HOW QUICKLY THE COLD AIR ARRIVES AND HOW SOON LAKE EFFECT SNOW
BEGINS.
A VERY STRONG LOW LEVEL JET OF 40 TO 60 KNOTS WILL BRING LOTS OF
GULF MOISTURE INTO THE UPPER PENINSULA WITH THE PROSPECT OF SOME
SIGNIFICANT RAINS TUESDAY NIGHT INTO WEDNESDAY. THE EASTERN HALF
OF THE AREA SHOULD RECEIVE THE BEST RAINS WITH SOME AREAS
RECEIVING AN INCH OR MORE. GUSTY SOUTH WINDS WILL ALSO KEEP
TEMPERATURES WAY ABOVE NORMAL THROUGH WEDNESDAY NIGHT DESPITE THE
RAIN.
COLDER AIR BEGINS TO ARRIVE THURSDAY AS THE SYSTEM INTENSIFIES AND
SPEEDS QUICKLY TOWARDS JAMES BAY. IN FACT THE DEEPENING LOW
PRESSURE AREA QUALIFIES AS EXPLOSIVE CYCLOGENESIS AND WILL PRODUCE
A STRONG PRESSURE GRADIENT THAT WILL PRODUCE STRONG WEST WINDS
THURSDAY AND THURSDAY NIGHT. GUSTS TO 40 MPH LIKELY OVER MOST OF
THE AREA WITH 50 MPH WINDS OVER THE KEWEENAW PENINSULA.
ALONG WITH THE STRONG WINDS COMES MUCH COLDER AIR. 850MB TEMPERATURES
DROP TO -12C BY THURSDAY EVENING AND REMAIN COLD ENOUGH FOR LAKE EFFECT
SNOW THROUGH SATURDAY NIGHT. THE LIMITING FACTOR WILL BE WIND DIRECTION
AS IT WILL BE LARGELY WESTERLY...WHICH FAVORS THE KEWEENAW PENINSULA.
A FEW INCHES OF SNOW LIKELY THERE THURSDAY WITH SIGNIFICANT SNOW AND
BLOWING SNOW POSSIBLE THURSDAY NIGHT AND FRIDAY. LIGHT SNOW SHOWERS
EXPECTED OUTSIDE THE KEWEENAW WITH A FEW INCHES LIKELY OVER THE
COURSE OF A FEW DAYS.
THE COLD AIR WILL REMAIN THROUGH SUNDAY WITH WARMER CONDITIONS
MONDAY AND TUESDAY AS UPPER RIDGE BUILDS AND SOUTHERLY WINDS BRING
MILDER AIR IN FROM THE SOUTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1200 AM EST TUE NOV 17 2015
INCREASING LOW-LEVEL MOISTURE AHEAD OF LOW PRES ORGANIZING OVER THE
PLAINS WILL LEAD TO AN OVERALL GRADUAL DETERIORATION OF CONDITIONS
DURING THIS FCST PERIOD. AT ALL TERMINALS...PERSISTENT LOW-LEVEL JET
OVER THE AREA WILL RESULT IN LLWS FOR MUCH OF THE PERIOD...
ESPECIALLY AT KCMX WHERE THERE WILL BE MORE OF A DIRECTIONAL CHANGE
OF WIND IN THE SHEAR LAYER. OTHERWISE...MVFR CONDITIONS AT KIWD WILL
SPREAD TO KCMX LATER IN THE NIGHT AND TO KSAW THIS MORNING. WITH
SHOWER COVERAGE INCREASING DURING THE AFTN AND EVENING...IFR OR EVEN
LIFR CONDITIONS WILL DEVELOP WITH THE LOWEST CONDITIONS AT KSAW DUE
TO MORE FAVORABLE UPSLOPE FLOW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED
AT 346 PM EST MON NOV 16 2015
A TIGHT PRESSURE GRADIENT WILL BE IN PLACE ACROSS THE REGION
BETWEEN HIGH PRESSURE OVER QUEBEC AND A TROUGH OF LOW PRESSURE
MOVING SLOWLY OVER THE PLAINS THROUGH WEDNESDAY. THIS TIGHT
PRESSURE GRADIENT WILL BRING A PROLONGED PERIOD OF GUSTY SOUTH TO
SOUTHEAST WINDS. SHORELINES EXPOSED TO WINDS FROM THESE DIRECTIONS WILL
SEE WAVES GREATER THAN 4 FEET DEVELOP...WHERE SMALL CRAFT
ADVISORIES ARE IN EFFECT. IN ADDITION...EASTERN PORTIONS OF LAKE
SUPERIOR CLOSER TO THE CANADIAN WATERS WILL SEE NEAR GALE FORCE
GUSTS AT TIMES. CONDITIONS LOOK A LITTLE TOO STABLE FOR WIDESPREAD
GALES TO OCCUR HOWEVER.
THEN A STRONG COLD FRONT WILL MOVE ACROSS THE REGION WEDNESDAY
NIGHT INTO THURSDAY. BEHIND THE FRONT...WIDESPREAD GALES ARE
LIKELY. NEAR STORM FORCE GUSTS WILL BE POSSIBLE OVER THE WESTERN
HALF OF LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SL/MPC
LONG TERM...RDM
AVIATION...ROLFSON
MARINE...MPC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
402 PM CST TUE NOV 17 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 401 PM CST TUE NOV 17 2015
THE BIGGEST ISSUE WILL BE DETERMINING TIMING AND POSITION OF A
POTENTIAL OF A DEFORMATION SNOW BAND TONIGHT. THIS WILL CREATE WIDE
VARIATIONS OF POTENTIAL SNOW AMOUNTS.
THE LATEST WATER VAPOR/SATELLITE LOOPS INDICATE THAT THE CLOSED LOW
RESPONSIBLE FOR OUR LATEST INCLEMENT WEATHER WAS NEAR THE
OKLAHOMA/KANSAS BORDER AND WILL EVENTUALLY PULL TO THE NORTHEAST.
WE ARE BASICALLY WAITING FOR SOME DYNAMIC COOLING TO OCCUR IN THE
ENTIRE COLUMN ABOVE THE SURFACE. UNTIL THEN...WE COULD FLUCTUATE
BETWEEN RAIN AND SNOW IN THE LOWER TO MID 40S ACROSS MUCH OF THE
WEST/NORTHWEST CWA. MODELS TEND TO BE IN GOOD AGREEMENT THAT BY 9
PM...ENOUGH COOLING WILL OCCUR TO CHANGE MOST OF THE PRECIPITATION
IN THE WEST TO SNOW. WITH CURRENT TEMPERATURES...THIS COULD MEAN A
RAPID SNOW ACCUMULATION. THE HRRR AND RAP INDICATE THAT THE
DEFORMATION BAND COULD BE QUITE A BIT FARTHER EAST THAN ORIGINALLY
THOUGHT. ALSO...OUR HIGHER QPF MIGHT OCCUR DURING THE OVERNIGHT
HOURS IN A VERY NARROW BAND. OUR MAJOR CONCERN IS WHERE THIS BAND
MAY PIVOT...WHICH CURRENTLY LOOKS LIKE IT COULD OCCUR SOMEWHERE OVER
DAWSON AND PERHAPS BUFFALO COUNTY...BUT CONFIDENCE IS NOT TERRIBLY
HIGH WITH THIS. I EXPANDED THE ADVISORY TO INCLUDE
VALLEY...SHERMAN...BUFFALO...AND PHELPS COUNTY...ON TOP OF THE
ORIGINAL THREE IN OUR WEST. DURING THE LATE AFTERNOON AND EARLY
EVENING...WE COULD EVEN HAVE A BRIEF PERIOD OF SLEET BEFORE CHANGE
TO SNOW LATER THIS EVENING.
FARTHER EAST...NOT TOO MUCH SNOW IF ANY EXPECTED AS TEMPERATURES
WILL GENERALLY NOT COOL DOWN ENOUGH TO SUPPORT MUCH SNOW
ACCUMULATION. ALSO ANOTHER WRENCH THROWN IN IS ANOTHER PERTURBATION
FOLLOWING BEHIND THE CURRENT ONE THAT COULD GIVE US ANOTHER SHOT OF
PRECIPITATION. BY WEDNESDAY AFTERNOON...HOWEVER...WE SHOULD BE WARM
ENOUGH THAT THIS WOULD BE PRIMARILY RAIN.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 401 PM CST TUE NOV 17 2015
MODELS ARE IN GOOD AGREEMENT AT THE START OF THE LONG TERM PERIOD
WEDNESDAY NIGHT...SHOWING THE MAIN UPPER LEVEL TROUGH AXIS
ASSOCIATED WITH AN AREA OF LOW PRESSURE OVER SOUTH CENTRAL CANADA
SWINGING THROUGH THE REGION. MORE AMPLIFIED NORTHWESTERLY FLOW ALOFT
BUILDS IN BEHIND THIS TROUGH AXIS...CONTINUING THROUGH
THURSDAY...AND DRY CONDITIONS REMAIN IN THE FORECAST EVEN INTO
THURSDAY NIGHT. AT THE SFC...FINALLY START TO SEE SOME RELIEF FROM
THE BREEZY/WINDY CONDITIONS...AS HIGH PRESSURE SETTLES IN OVER KS
DURING THE DAY ON THURSDAY. NRN PORTIONS OF THE CWA MAY KEEP 15 TO
20 MPH SPEEDS AROUND INTO THURSDAY MORNING...AS THEY WILL BE CLOSER
TO THE MAIN SFC LOW SLIDING THROUGH PORTIONS OF ONTARIO AND UNDER A
TIGHTER PRESSURE GRADIENT. BY THE END OF THE DAY THURSDAY SPEEDS
LOOK TO BE AROUND 10 MPH. CONFIDENCE IN HIGHS ON THURSDAY IS NOT
HIGH...ESP ACROSS THE WEST...WHICH WILL BE AFFECTED BY WHATEVER
SNOWFALL THEY GET THE REST OF TODAY. CURRENT FORECAST CALLS FOR
LOWER 40S IN THE NW...TO NEAR 50 IN THE SOUTHEAST.
THE NEXT CHANCE FOR PRECIPITATION LOOKS TO AFFECT THE CWA AS WE GET
INTO FRIDAY/FRIDAY NIGHT. MODELS SHOWING A QUICK MOVING UPPER LEVEL
DISTURBANCE SLIDING IN FROM THE NORTHWEST...ACCOMPANIED BY INCREASED
LIFT VIA AN UPPER LEVEL JET STREAK. NOT EXPECTING A LOT OF
ACCUMULATION DUE TO ITS PROGRESSIVE NATURE...BUT NRN PORTIONS OF THE
CWA COULD PICK UP AN INCH OF SNOW. FURTHER SOUTH /ROUGHLY I-80 AND
SOUTH/...WITH MORE UNCERTAINTY IN DAYTIME TEMPS...HAVE A RA OR RA/SN
MIX GOING.
THE FORECAST FOR THE REST OF THE LONG TERM...SAT THROUGH
MON...REMAINS DRY. AFTER THE PRECIPITATION CHANCES FRIDAY...UPPER
LEVEL NORTHWESTERLY FLOW BUILDS BACK IN ACROSS THE REGION...THOUGH
THE GFS SUGGEST ANOTHER QUICK MOVING DISTURBANCE COULD BRING A
CHANCE AT PRECIP AGAIN SUNDAY. WOULD LIKE TO SEE SOME RUN TO RUN
SUPPORT /WASNT PRESENT IN THE 06Z RUN/ AND SUPPORT FROM OTHER MODELS
BEFORE INSERTING ANY POPS. EXPECTING BELOW NORMAL HIGHS THROUGH THE
WEEKEND...MID 30S TO LOWER 40S SAT AND LOWER/MID 40S SUN...BEFORE
BUMPING BACK CLOSER TO NORMAL /UPPER 40S TO LOWER 50S/ FOR MON.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1212 PM CST TUE NOV 17 2015
CEILINGS AND VISIBILITY ARE SOMEWHAT LOW CONFIDENCE AS THESE HAVE
A GOOD CHANCE OF BEING VARIABLE AS A WINTER SYSTEM PULLS THROUGH
THE AREA. STRONG WIND GUSTS FROM THE NORTH ARE A GOOD BET THROUGH
THIS EVENING. PERIODS OF PRECIPITATION WILL EVENTUALLY TURN FROM
RAIN TO SNOW BY THIS EVENING. A NARROW DEFORMATION BAND LOOKS
LIKELY TO SET UP THIS EVENING AND SHOULD BE WEST OF BOTH
TERMINALS...BUT MODELS ARE TRENDING FARTHER EAST LATELY...WHICH
MAY DRAW VISIBILITY AT KEAR IN QUESTION AND COULD BE LOWER THAN
CURRENTLY FORECAST...ESPECIALLY BETWEEN 03Z AND 09Z.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 6 AM CST WEDNESDAY FOR NEZ039-046-
060-061-072-073-082.
KS...NONE.
&&
$$
SHORT TERM...HEINLEIN
LONG TERM...ADP
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1216 PM CST TUE NOV 17 2015
.SYNOPSIS...
ISSUED AT 326 AM CST TUE NOV 17 2015
THE SURFACE ANALYSIS FROM 06Z SHOWED A COLD FRONT ACROSS THE EASTERN
DAKOTAS...THROUGH NORTH CENTRAL AND SOUTHWEST NEBRASKA INTO NORTHERN
COLORADO. THERE WAS A LOW PRESSURE CENTER IN EXTREME NORTHEAST NEW
MEXICO AND THE OKLAHOMA PANHANDLE PUMPING MOIST AIR TOWARD THE
FRONT. IN THE UPPER LEVELS...THE 08Z WATER VAPOR IMAGERY SHOWED THE
MAIN CIRCULATION IN THE SOUTHWEST JUST EAST OF THE FOUR CORNERS
AREA.
&&
.UPDATE...
ISSUED AT 1215 AM CST TUE NOV 17 2015
MORNING MODELS HAVE SHIFTED THE HEAVY SNOW BAND TO THE EAST ABOUT
50 MILES OR SO. THIS PLACES GREAT CONCERN FOR THE ONGOING
HEADLINES FOR WESTERN NEBRASKA. WILL NOT ADJUST HEADLINES YET AS
WE WAIT FOR THE BAND TO DEVELOP...WHICH HAS STARTED TO FILL IN
OVER SOUTHWEST INTO CENTRAL NEBRASKA. CHANGES ARE LIKELY IN THE
NEXT FEW HOURS. STILL LOOKING LIKE A HEAVY BAND WITH SNOWFALL OF
MORE THAN 6 INCHES...JUST A LITTLE SHIFT TO THE EAST OF PREVIOUS
THOUGHTS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CST TUE NOV 17 2015
THE MODELS INDICATE SOMETHING VERY INTERESTING WILL HAPPEN TODAY AND
TONIGHT. SFC WINDS OF 25 TO 35 MPH THIS MORNING WILL REMAIN STRONG
ALL DAY AND DIMINISH SOMEWHAT THIS EVENING AFTER SUNSET. A HEAVY
SNOW BAND OF 1 TO 2 INCHES PER HOUR RATES SHOULD FORM ACROSS SWRN
NEB THIS MORNING AND LIFT SLOWLY NORTH INTO NCNTL NEB THIS AFTERNOON
AND THIS EVENING. THE COMBINATION OF STRONG WINDS AND HEAVY SNOW
WOULD CERTAINLY PRODUCE BLIZZARD CONDITIONS IF THE MODELS ARE
CORRECT. WPC HAS RAISED THEIR SNOWFALL FORECAST TO 8 TO 15 PLUS
INCHES ACROSS SWRN NEB NORTHEAST THROUGH LINCOLN AND EVEN INTO LOGAN
COUNTY.
A BLIZZARD WARNING WILL BE ISSUED FOR THESE AREAS. LOGAN COUNTY IS
UNDER REVIEW FOR AN UPGRADE AT THIS POINT PENDING THE PROGRESS OF
THIS WEATHER SITUATION. VIRTUALLY EVERY MODEL...9 OF THEM...FORECAST
500M AGL WINDS OF 25 TO 35 KT WHICH SHOULD PRODUCE SFC WINDS OF 25
TO 35 MPH GUSTING TO 40 TO 45 MPH.
SO CONFIDENCE IS MODERATE FOR THIS FORECAST. COLD AIR IS POURING
INTO WRN NEB WITH ALL AREAS IN SNOW WEST OF HIGHWAY 61. THIS APPEARS
TO BE CLOSE TO OR SLIGHTLY AHEAD OF THE FORECAST. THIS RAIN-SNOW
LINE WILL CONTINUE MOVING EAST TODAY AND BE VERY CLOSE TO THE ERN
EDGE OF HOLT COUNTY WEDNESDAY MORNING.
THE RAP INDICATES AROUND AN INCH OF RAIN-SNOW WATER THROUGH 02Z THIS
EVENING ACROSS SWRN NEB AND THE 06Z NAM SHOWS 1 TO 2 INCHES IN THE
SAME AREA THROUGH 03Z THIS EVENING. THE NAM HAS BE HITTING SWRN NEB
HARD FOR SEVERAL MODEL RUNS NOW AND SHOWS NO SIGN OF BACKING OFF.
NOTE THAT THE MID LEVEL WARM AIR ADVECTION IS SO STRONG...A WARM
NOSE DEVELOPS WHICH WILL PRODUCE A PERIOD OF SLEET AND PERHAPS
FREEZING RAIN BEFORE CHANGEOVER OCCURS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 326 AM CST TUE NOV 17 2015
A FEW LINGERING LIGHT SHOWERS ARE STILL POSSIBLE UNTIL LATE
WEDNESDAY AFTERNOON AS A BAND OF ELEVATED FRONTOGENESIS FOLLOWS IN
THE WAKE OF THE UPPER TROUGH. SNOW CHANGING TO RAIN CAN BE EXPECTED
WEDNESDAY MORNING.
ON THURSDAY EVENING...CYCLOGENESIS IN WEST CENTRAL AND SOUTHWEST
WYOMING WILL RESULT IN ANOTHER STORM SYSTEM COMING ACROSS NEBRASKA.
AS THE ACCOMPANYING FRONT PLUNGES THROUGH...SYSTEM-RELATIVE
ISENTROPIC LIFT OF NEARLY SATURATED AIR WILL GENERATE SOME LIGHT
SNOW FRIDAY OVER NORTHERN NEBRASKA WITH SOME ACCUMULATION POSSIBLE.
IN ITS WAKE...CANADIAN HIGH PRESSURE WILL CUT OFF FLOW FROM THE
SOUTH AND DRIER WEATHER CAN BE EXPECTED FOR THE WEEKEND AND EARLY
NEXT WEEK. INDICATIONS ARE THAT THE CANADIAN AIR MASS WILL BRING
SOME VERY COLD TEMPERATURES OF 10 TO 15 DEGREES...OR EVEN COLDER...
TO CENTRAL AND WESTERN NEBRASKA FRIDAY NIGHT AND SATURDAY NIGHT WITH
HIGHS SATURDAY MAINLY IN THE 30S.
AS THE HIGH GOES INTO THE SOUTHEAST U.S. RETURN FLOW WILL BRING
SOME WARMER TEMPERATURES TO CENTRAL AND WESTERN NEBRASKA MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1215 AM CST TUE NOV 17 2015
CONDITIONS DETERIORATING FOR KLBF THIS AFTERNOON AS A BAND OF
SNOW DEVELOPS OVERHEAD. VISIBILITIES TO LESS THAN A MILE AT TIMES
AND COULD DROP TO 1/2SM OR LESS AT TIMES. IMPROVING CONDITIONS NOT
EXPECTED UNTIL LATER THIS EVENING OR OVERNIGHT. SNOW ENDS
OVERNIGHT WITH VFR CONDITIONS DEVELOPING AND CONTINUING TOMORROW.
KVTN ON THE OTHER HAND IS WELL NW OF THE EXPECTED BAND. CANNOT
RULE OUT SOME LIGHT RAIN OR LIGHT SNOW THIS AFTERNOON...HOWEVER DO
EXPECT MVFR CIGS TO CONTINUE. VFR CONDITIONS DEVELOP TOWARDS
MORNING AND CONTINUE THROUGH THE DAY TOMORROW.
WIDE SPREAD GUSTY NORTHWEST WINDS TODAY...GUSTING TO 30 TO 40 KTS
ALL AFTERNOON. LIGHTER WINDS DEVELOP AFTER MIDNIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
BLIZZARD WARNING UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT FOR
NEZ058-069-070.
BLIZZARD WARNING UNTIL 6 AM CST WEDNESDAY FOR NEZ059.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT
FOR NEZ004-094.
WINTER STORM WARNING UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT FOR
NEZ022>024-035-036-056-057.
WINTER WEATHER ADVISORY UNTIL 6 AM CST /5 AM MST/ WEDNESDAY FOR
NEZ005-008-025-026-037-071.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 6 AM CST
WEDNESDAY FOR NEZ038.
&&
$$
UPDATE...MASEK
SYNOPSIS...SPRINGER
SHORT TERM...CDC
LONG TERM...SPRINGER
AVIATION...MASEK
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
537 AM CST TUE NOV 17 2015
.SYNOPSIS...
ISSUED AT 326 AM CST TUE NOV 17 2015
THE SURFACE ANALYSIS FROM 06Z SHOWED A COLD FRONT ACROSS THE EASTERN
DAKOTAS...THROUGH NORTH CENTRAL AND SOUTHWEST NEBRASKA INTO NORTHERN
COLORADO. THERE WAS A LOW PRESSURE CENTER IN EXTREME NORTHEAST NEW
MEXICO AND THE OKLAHOMA PANHANDLE PUMPING MOIST AIR TOWARD THE
FRONT. IN THE UPPER LEVELS...THE 08Z WATER VAPOR IMAGERY SHOWED THE
MAIN CIRCULATION IN THE SOUTHWEST JUST EAST OF THE FOUR CORNERS
AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CST TUE NOV 17 2015
THE MODELS INDICATE SOMETHING VERY INTERESTING WILL HAPPEN TODAY AND
TONIGHT. SFC WINDS OF 25 TO 35 MPH THIS MORNING WILL REMAIN STRONG
ALL DAY AND DIMINISH SOMEWHAT THIS EVENING AFTER SUNSET. A HEAVY
SNOW BAND OF 1 TO 2 INCHES PER HOUR RATES SHOULD FORM ACROSS SWRN
NEB THIS MORNING AND LIFT SLOWLY NORTH INTO NCNTL NEB THIS AFTERNOON
AND THIS EVENING. THE COMBINATION OF STRONG WINDS AND HEAVY SNOW
WOULD CERTAINLY PRODUCE BLIZZARD CONDITIONS IF THE MODELS ARE
CORRECT. WPC HAS RAISED THEIR SNOWFALL FORECAST TO 8 TO 15 PLUS
INCHES ACROSS SWRN NEB NORTHEAST THROUGH LINCOLN AND EVEN INTO LOGAN
COUNTY.
A BLIZZARD WARNING WILL BE ISSUED FOR THESE AREAS. LOGAN COUNTY IS
UNDER REVIEW FOR AN UPGRADE AT THIS POINT PENDING THE PROGRESS OF
THIS WEATHER SITUATION. VIRTUALLY EVERY MODEL...9 OF THEM...FORECAST
500M AGL WINDS OF 25 TO 35 KT WHICH SHOULD PRODUCE SFC WINDS OF 25
TO 35 MPH GUSTING TO 40 TO 45 MPH.
SO CONFIDENCE IS MODERATE FOR THIS FORECAST. COLD AIR IS POURING
INTO WRN NEB WITH ALL AREAS IN SNOW WEST OF HIGHWAY 61. THIS APPEARS
TO BE CLOSE TO OR SLIGHTLY AHEAD OF THE FORECAST. THIS RAIN-SNOW
LINE WILL CONTINUE MOVING EAST TODAY AND BE VERY CLOSE TO THE ERN
EDGE OF HOLT COUNTY WEDNESDAY MORNING.
THE RAP INDICATES AROUND AN INCH OF RAIN-SNOW WATER THROUGH 02Z THIS
EVENING ACROSS SWRN NEB AND THE 06Z NAM SHOWS 1 TO 2 INCHES IN THE
SAME AREA THROUGH 03Z THIS EVENING. THE NAM HAS BE HITTING SWRN NEB
HARD FOR SEVERAL MODEL RUNS NOW AND SHOWS NO SIGN OF BACKING OFF.
NOTE THAT THE MID LEVEL WARM AIR ADVECTION IS SO STRONG...A WARM
NOSE DEVELOPS WHICH WILL PRODUCE A PERIOD OF SLEET AND PERHAPS
FREEZING RAIN BEFORE CHANGEOVER OCCURS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 326 AM CST TUE NOV 17 2015
A FEW LINGERING LIGHT SHOWERS ARE STILL POSSIBLE UNTIL LATE
WEDNESDAY AFTERNOON AS A BAND OF ELEVATED FRONTOGENESIS FOLLOWS IN
THE WAKE OF THE UPPER TROUGH. SNOW CHANGING TO RAIN CAN BE EXPECTED
WEDNESDAY MORNING.
ON THURSDAY EVENING...CYCLOGENESIS IN WEST CENTRAL AND SOUTHWEST
WYOMING WILL RESULT IN ANOTHER STORM SYSTEM COMING ACROSS NEBRASKA.
AS THE ACCOMPANYING FRONT PLUNGES THROUGH...SYSTEM-RELATIVE
ISENTROPIC LIFT OF NEARLY SATURATED AIR WILL GENERATE SOME LIGHT
SNOW FRIDAY OVER NORTHERN NEBRASKA WITH SOME ACCUMULATION POSSIBLE.
IN ITS WAKE...CANADIAN HIGH PRESSURE WILL CUT OFF FLOW FROM THE
SOUTH AND DRIER WEATHER CAN BE EXPECTED FOR THE WEEKEND AND EARLY
NEXT WEEK. INDICATIONS ARE THAT THE CANADIAN AIR MASS WILL BRING
SOME VERY COLD TEMPERATURES OF 10 TO 15 DEGREES...OR EVEN COLDER...
TO CENTRAL AND WESTERN NEBRASKA FRIDAY NIGHT AND SATURDAY NIGHT WITH
HIGHS SATURDAY MAINLY IN THE 30S.
AS THE HIGH GOES INTO THE SOUTHEAST U.S. RETURN FLOW WILL BRING
SOME WARMER TEMPERATURES TO CENTRAL AND WESTERN NEBRASKA MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 536 AM CST TUE NOV 17 2015
MIXED MVFR/IFR/LIFR CONDITIONS CONTINUE TODAY AND TONIGHT
ASSOCIATED WITH A DEEP STORM SYSTEM FORECAST TO TRACK THROUGH
NEBRASKA. SOME IMPROVEMENT SHOULD OCCUR FROM WEST TO EAST TONIGHT
AS DRY AIR MOVES IN AND CAUSES CIGS TO LIFT.
WINDS 36027G35KT TODAY DECREASE TO 33020G30KT THIS EVENING AND TO 33015KT
BY 06Z TONIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
BLIZZARD WARNING UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT FOR
NEZ058-069-070.
BLIZZARD WARNING FROM NOON TODAY TO 6 AM CST WEDNESDAY FOR
NEZ059.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT
FOR NEZ004-094.
WINTER STORM WARNING UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT FOR
NEZ022>024-035-036-056-057.
WINTER WEATHER ADVISORY FROM NOON CST /11 AM MST/ TODAY TO 6 AM
CST /5 AM MST/ WEDNESDAY FOR NEZ005-008-025-026-037-071.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 6 AM CST
WEDNESDAY FOR NEZ038.
&&
$$
SYNOPSIS...SPRINGER
SHORT TERM...CDC
LONG TERM...SPRINGER
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
328 AM CST TUE NOV 17 2015
.SYNOPSIS...
ISSUED AT 326 AM CST TUE NOV 17 2015
THE SURFACE ANALYSIS FROM 06Z SHOWED A COLD FRONT ACROSS THE EASTERN
DAKOTAS...THROUGH NORTH CENTRAL AND SOUTHWEST NEBRASKA INTO NORTHERN
COLORADO. THERE WAS A LOW PRESSURE CENTER IN EXTREME NORTHEAST NEW
MEXICO AND THE OKLAHOMA PANHANDLE PUMPING MOIST AIR TOWARD THE
FRONT. IN THE UPPER LEVELS...THE 08Z WATER VAPOR IMAGERY SHOWED THE
MAIN CIRCULATION IN THE SOUTHWEST JUST EAST OF THE FOUR CORNERS
AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 326 AM CST TUE NOV 17 2015
THE MODELS INDICATE SOMETHING VERY INTERESTING WILL HAPPEN TODAY AND
TONIGHT. SFC WINDS OF 25 TO 35 MPH THIS MORNING WILL REMAIN STRONG
ALL DAY AND DIMINISH SOMEWHAT THIS EVENING AFTER SUNSET. A HEAVY
SNOW BAND OF 1 TO 2 INCHES PER HOUR RATES SHOULD FORM ACROSS SWRN
NEB THIS MORNING AND LIFT SLOWLY NORTH INTO NCNTL NEB THIS AFTERNOON
AND THIS EVENING. THE COMBINATION OF STRONG WINDS AND HEAVY SNOW
WOULD CERTAINLY PRODUCE BLIZZARD CONDITIONS IF THE MODELS ARE
CORRECT. WPC HAS RAISED THEIR SNOWFALL FORECAST TO 8 TO 15 PLUS
INCHES ACROSS SWRN NEB NORTHEAST THROUGH LINCOLN AND EVEN INTO LOGAN
COUNTY.
A BLIZZARD WARNING WILL BE ISSUED FOR THESE AREAS. LOGAN COUNTY IS
UNDER REVIEW FOR AN UPGRADE AT THIS POINT PENDING THE PROGRESS OF
THIS WEATHER SITUATION. VIRTUALLY EVERY MODEL...9 OF THEM...FORECAST
500M AGL WINDS OF 25 TO 35 KT WHICH SHOULD PRODUCE SFC WINDS OF 25
TO 35 MPH GUSTING TO 40 TO 45 MPH.
SO CONFIDENCE IS MODERATE FOR THIS FORECAST. COLD AIR IS POURING
INTO WRN NEB WITH ALL AREAS IN SNOW WEST OF HIGHWAY 61. THIS APPEARS
TO BE CLOSE TO OR SLIGHTLY AHEAD OF THE FORECAST. THIS RAIN-SNOW
LINE WILL CONTINUE MOVING EAST TODAY AND BE VERY CLOSE TO THE ERN
EDGE OF HOLT COUNTY WEDNESDAY MORNING.
THE RAP INDICATES AROUND AN INCH OF RAIN-SNOW WATER THROUGH 02Z THIS
EVENING ACROSS SWRN NEB AND THE 06Z NAM SHOWS 1 TO 2 INCHES IN THE
SAME AREA THROUGH 03Z THIS EVENING. THE NAM HAS BE HITTING SWRN NEB
HARD FOR SEVERAL MODEL RUNS NOW AND SHOWS NO SIGN OF BACKING OFF.
NOTE THAT THE MID LEVEL WARM AIR ADVECTION IS SO STRONG...A WARM
NOSE DEVELOPS WHICH WILL PRODUCE A PERIOD OF SLEET AND PERHAPS
FREEZING RAIN BEFORE CHANGEOVER OCCURS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 326 AM CST TUE NOV 17 2015
A FEW LINGERING LIGHT SHOWERS ARE STILL POSSIBLE UNTIL LATE
WEDNESDAY AFTERNOON AS A BAND OF ELEVATED FRONTOGENESIS FOLLOWS IN
THE WAKE OF THE UPPER TROUGH. SNOW CHANGING TO RAIN CAN BE EXPECTED
WEDNESDAY MORNING.
ON THURSDAY EVENING...CYCLOGENESIS IN WEST CENTRAL AND SOUTHWEST
WYOMING WILL RESULT IN ANOTHER STORM SYSTEM COMING ACROSS NEBRASKA.
AS THE ACCOMPANYING FRONT PLUNGES THROUGH...SYSTEM-RELATIVE
ISENTROPIC LIFT OF NEARLY SATURATED AIR WILL GENERATE SOME LIGHT
SNOW FRIDAY OVER NORTHERN NEBRASKA WITH SOME ACCUMULATION POSSIBLE.
IN ITS WAKE...CANADIAN HIGH PRESSURE WILL CUT OFF FLOW FROM THE
SOUTH AND DRIER WEATHER CAN BE EXPECTED FOR THE WEEKEND AND EARLY
NEXT WEEK. INDICATIONS ARE THAT THE CANADIAN AIR MASS WILL BRING
SOME VERY COLD TEMPERATURES OF 10 TO 15 DEGREES...OR EVEN COLDER...
TO CENTRAL AND WESTERN NEBRASKA FRIDAY NIGHT AND SATURDAY NIGHT WITH
HIGHS SATURDAY MAINLY IN THE 30S.
AS THE HIGH GOES INTO THE SOUTHEAST U.S. RETURN FLOW WILL BRING
SOME WARMER TEMPERATURES TO CENTRAL AND WESTERN NEBRASKA MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1135 PM CST MON NOV 16 2015
FOR THE KLBF TERMINAL...THE THREAT FOR THUNDERSTORMS HAS ENDED FOR
TONIGHT...HOWEVER...MVFR CIGS AROUND 1500 FT AGL AND LIGHT RAIN
WILL BE POSSIBLE OVERNIGHT TONIGHT THROUGH MID MORNING TUESDAY. BY
LATE MORNING TUESDAY...LOOK FOR CIGS TO FALL BELOW 1000 FT AGL
WITH RAIN AND PATCHY FOG WITH VISBYS DOWN TO 3SM. RAIN WILL
GRADUALLY MIX WITH...BEFORE CHANGING OVER TO ALL SNOW BY LATE
AFTERNOON. PERIODIC VISBYS OF 1SM ARE EXPECTED. BY TUES
EVENING...SNOW IS LIKELY WITH VISBYS DOWN TO 1/2SM AND CIGS OF
200 FT AGL. SNOWFALL RATES AND VISBYS MAY BE EVEN LOWER TUES
EVENING...BUT CONFIDENCE IN THIS IS TOO LOW ATTM TO INCLUDE IT IN
THE 06Z TAF. FOR THE KVTN TERMINAL...LIGHT RAIN WILL CONTINUE INTO
THE OVERNIGHT WITH CIGS AROUND 3000 FT AGL. FOR TUESDAY...VISBYS
WILL DECREASE TO THE 1 TO 2SM RANGE WITH LIGHT SNOW DEVELOPING
DURING THE LATE AFTERNOON HOURS. CIGS MAY FALL OFF TO UNDER 1000
FT AGL DURING THE LATE AFTERNOON INTO THE EARLY EVENING HOURS. FOR
BOTH TERMINALS...STRONG NORTHERLY WINDS ARE EXPECTED OVER THE NEXT
24 HOURS AND MAY GUST UP TO 38 KTS...ESPECIALLY DURING THE DAY ON
TUESDAY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
BLIZZARD WARNING UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT FOR
NEZ058-069-070.
BLIZZARD WARNING FROM NOON TODAY TO 6 AM CST WEDNESDAY FOR
NEZ059.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT
FOR NEZ004-094.
WINTER STORM WARNING UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT FOR
NEZ022>024-035-036-056-057.
WINTER WEATHER ADVISORY FROM NOON CST /11 AM MST/ TODAY TO 6 AM
CST /5 AM MST/ WEDNESDAY FOR NEZ005-008-025-026-037-071.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 6 AM CST
WEDNESDAY FOR NEZ038.
&&
$$
SYNOPSIS...SPRINGER
SHORT TERM...CDC
LONG TERM...SPRINGER
AVIATION...BUTTLER
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
909 PM EST WED NOV 18 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM OVER THE WESTERN GREAT LAKES WILL PUSH A
COLD FRONT THROUGH OUR AREA TOMORROW, BRINGING WINDY CONDITIONS
WITH RAIN SHOWERS. COOLER AIR WILL FOLLOW THE FRONT FOR THE
WEEKEND WITH RAIN AND SNOW SHOWERS.
&&
.NEAR TERM /THROUGH THURSDAY/...
9 PM UPDATE...
AS FORECAST BY THE PREVIOUS SHIFT, THE SHOWER ACTIVITY IS SPARSE
AND STILL A WAYS OFF, DESPITE THE AGGRESSIVE PUSH NORTHEASTWARD BY
A PRIOR HRRR RUN.
MAIN CHANGE FOR THE OVERNIGHT PERIOD WAS TO INCREASE TEMPERATURES
TOWARD SUNRISE, AS WARM AIR IS MAKING A STRONG PUSH OUT OF PA INTO
SWRN NY.
4 PM UPDATE...
TGT GRADIENT WILL KEEP THE LOW CLDS AND WINDS UP OVRNGT...BUT THE
BULK OF THE SHWRS WILL HOLD OFF UNTIL THU. LOW CLDS CONT TO STREAM
NWRD WITH THE LL MOIST FLOW OFF THE WRN ATLANTIC. DOWNSLOPING HAS
LIMITED THE CLDS IN THE MOHAWK VALLEY INTO THE SYR AREA...BUT XPCT
THE CLDS TO EXPAND OVRNGT INTO THOSE AREAS. SC DECK HAS HELPED
MAINTAIN A MORE STABLE LYR NEARER THE SFC AND LIMITED THE AMT OF
HIGH WINDS THAT HAVE BEEN SEEN AT THE SFC. XPCT THIS TO CONT
OVRNGT WITH HEALTHY 40 KT GUSTS ZIPPING ALONG ABV. HIGHEST GUSTS
WILL CONT TO BE OVER THE HIGHER RIDGES OF THE FINGER LAKES...ESP
IN THE WEST.
WITH THE SHRP RDG HOLDING IN THE EAST AND THE UPR LOW WELL WEST
OVER ERN MN...RAIN WILL HOLD OFF FOR MUCH OF THE NGT...OTR THAN A
FEW SPRINKLES OVER THE EAST AND SOUTH. LTR TNGT...SHRT WV AND
DVLPG JET MAX WILL GENERATE A GOOD AREA OF PCPN PUSHING INTO THE
WRN ZONES ARND 09Z...AND CONTG TO SPREAD EAST.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
SOLID AREA OF PCPN MARCHES EAST ON SAT WITH THE WV AND UPR JET.
CAT POPS SEEM RSNBL GIVEN THE CONFIDENCE IN THE ABILITY OF THE FNT
TO GENERATE RAIN...AND THE HISTORY OF THE SYSTEM. FNT AND UPR
SUPPORT IS PROGRESSIVE AND WILL MSTLY BE EAST OF THE AREA BY 00Z
FRI. RAINFALL AMTS SHD NOT BE EXCESSIVE WITH THE MVMT AND SPEED OF
THE FNT...GNRLY LESS THAN 3/4 INCH.
IN THE WAKE OF THE FNT AND WV...AREA REMAINS IN A BROAD UPR TROF
CNTRD OVER CNTRL LAKES. SWLY FLOW CONTS THRU THE END OF THE SHRT
TERM. WITH MRNGL H8 TEMPS AND FLOW DIRECTION NOT FVRBL FOR THE
FCST AREA...XPCT VERY LIMITED LE SHWRS THRU SAT...WITH THE BEST
CHANCE FOR ISLTD RAINS SHWRS OVER THE FINGER LAKES.
TEMPS WILL DROP CONSIDERABLY AFT THU BUT STILL MAY BE SLGTLY ABV
NRML FOR MID NOV.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A SHORTWAVE TROUGH WILL START TO MOVE THROUGH THE REGION SATURDAY
EVENING AND FORCE A SFC LOW ACROSS THE AREA. THIS SYSTEM WILL BRING
COOLER TEMPS ALONG WITH THE CHANCE FOR RAIN/SNOW SHOWERS. THE UPPR
LVL TROUGH WILL SLOWLY MOVE EAST AND SHIFT EAST OF THE REGION BY
MONDAY EVENING. LAKE EFFECT SHOWERS WILL FOLLOW IN THE SYSTEM`S
WAKE. HIGH PRESSURE WILL BUILD OVER CENTRAL NY AND NORTHEAST PA ON
TUESDAY PUTTING AN END TOWARDS SHOWERS OVER THE REGION. LARGE
DISCREPANCIES EXIST WITHIN GUIDANCE STARTING THURSDAY OF NEXT WEEK
THROUGH THE EXTENDED PORTION OF THE FORECAST. DECIDED TO KEEP THE
FORECAST DRY AS CONFIDENCE IS LOW ON ANY SOLUTION.
TEMPS DURING THE FORECAST PERIOD WILL BE CLOSE TO THE SEASONAL
AVERAGE.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
GUSTY WINDS CONTINUE ACROSS THE REGION THIS EVENING... WITH GUSTS
UP TO 35 KNOTS AS THE NEXT STORM SYSTEM APPROACHES. THE GUSTY
WIND IS THE RESULT OF A STRONG LOW LEVEL JET. THIS JET IS ALSO
FORCING MOIST AIR OVER THE REGION. MVFR CEILINGS ARE THE RESULT
FROM THE STRONG LLJ. THIS STRONG LLJ WILL ALSO CREATE LOW LEVEL
WIND SHEAR ACROSS ALL TAF SITES THIS EVENING. WINDS AROUND 2000 FT
RANGE FROM 50 TO 60 KNOTS. THIS LLWS IS EXPECTED TO LAST THROUGH
MID MORNING.
THIS SYSTEM WILL ALSO BRING RAIN SHOWERS TO THE AREA. SHOWERS ARE
EXPECTED TO DEVELOP A BIT LATER THAN PREVIOUSLY THOUGHT... CLOSER
TO 12Z. SHOWERS ARE EXPECTED TO BE HEAVY AT TIMES AND MAY PRODUCE
IFR CONDITIONS... BUT CONFIDENCE IS TO LOW ATTM TO MENTION IN
TAFS. WINDS WILL BECOME WEAKER BY THURSDAY AFTERNOON.
.OUTLOOK...
THURSDAY EVENING... RESTRICTIONS EXPECTED IN SHOWERS.
FRIDAY-SATURDAY... VFR.
SUN AND MON... RESTRICTIONS POSSIBLE IN SHOWERS, ESPECIALLY FOR
THE CENTRAL NY TERMINAL SITES.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
NEAR TERM...DGM/DJP
SHORT TERM...DGM
LONG TERM...KAH
AVIATION...KAH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1038 PM EST WED NOV 18 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH THE MOUNTAINS FROM THE WEST
THIS EVENING...THEN TRACK EAST ACROSS THE CAROLINAS THURSDAY. HIGH
PRESSURE WILL BUILD INTO THE REGION FROM THE WEST ON FRIDAY. A
MAINLY DRY COLD FRONT WILL SWEEP ACROSS THE AREA SATURDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 1030 PM WEDNESDAY...
DEEP MID/UPPER LEVEL TROUGH CENTERED OVER THE CENTRAL PART OF THE
COUNTRY WILL CONTINUE TO SLOWLY SHIFT EASTWARD TONIGHT... WHILE THE
MAIN STACK LOW PRESSURE CENTER WILL CONTINUE TO LIFT NORTH-
NORTHEASTWARD OVERNIGHT INTO SOUTHERN CANADA. THE ASSOCIATED SURFACE
COLD FRONT WILL CONTINUE TO APPROACH THE AREA FROM THE WEST
OVERNIGHT... CURRENTLY EXTENDED SOUTHWARD FROM THE TN/KY INTO
EASTERN AL. THE FRONT SHOULD REMAIN TO THE WEST OF THE AREA
OVERNIGHT THOUGH. HOWEVER... A PREFRONTAL BAND OF SHOWERS AND EVEN
SOME ISOLATED THUNDERSTORMS WILL MOVE INTO THE AREA TONIGHT (MOVING
INTO WESTERN PORTIONS OF THE AREA NOW). THE BEST DYNAMICS WILL PASS
TO THE NORTH OF THE AREA AS THE MID LEVEL TROUGH DEAMPLIFIES AND
BROADENS. HOWEVER... WITH A GOOD SOUTHERLY LOW LEVEL FLOW AND STILL
GOOD MOISTURE TRANSPORT WE SHOULD SEE PW`S CLIMB TO AROUND 1.75" TO
2.0" OVERNIGHT. THUS... WE WILL SEE SOME MODERATE TO AT TIMES HEAVY
RAIN. HOWEVER... WITH FLASH FLOOD GUIDANCE GENERALLY ABOVE 2 INCHES
FOR ONE HOUR AND AROUND 2.5 TO 3 INCHES FOR 3 HOURS... THINK WE
SHOULD BE OK OUTSIDE OF POSSIBLY SOME MINOR FLOODING IN URBAN AREAS
(BEST CHANCES ACROSS THE TRIAD... WHERE WE COULD SEE RAINFALL
AMOUNTS OF AROUND 1 TO 1.5 INCHES). WITH REGARD TO A SEVERE
THREAT... THE LATEST RAP AND GFS CONTINUE TO SHOW WEAK INSTABILITY
INCREASING LATE TONIGHT WITH THE WAA... WITH UP TO 400-500 J/KG OF
MLCAPE BY AROUND 12Z ACROSS THE SOUTHWESTERN PIEDMONT AND SOUTHERN
SANDHILLS. THE LATEST DAY1 SPC CONVECTIVE OUTLOOK BRINGS THE
MARGINAL RISK VERY NEAR OUR SOUTHERN/SOUTHWESTERN COUNTIES. GIVEN
THE TIME OF DAY AND LACK OF ANY SEVERE WEATHER OVER THE LAST SEVERAL
HOURS... WOULD ANTICIPATE THIS THREAT TO BE QUITE SMALL... BUT NOT
ZERO GIVEN THE GOOD DEEP SHEAR (IF ENOUGH INSTABILITY ADVECTS
IN)...WITH THE MAIN THREAT FROM A VERY WEAK BRIEF TORNADO AND/OR
DAMAGING WIND GUST. TEMPS WILL GENERALLY REMAIN STEADY OVERNIGHT...
POSSIBLY EVEN INCREASING A DEGREE OR TWO ACROSS EASTERN PORTIONS OF
THE AREA... GENERALLY MID TO UPPER 60S.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 320 PM WEDNESDAY...
MODEL GUIDANCE REMAINS CONSISTENT AND IN FAIRLY GOOD AGREEMENT ON
THE TIMING OF THE COLD FRONT THROUGH CENTRAL NC BETWEEN MID MORNING
AND EARLY EVENING THU (ALTHOUGH THE CHILLIER AND MUCH DRIER AIR WILL
TAKE AWHILE LONGER TO SCALE THE MOUNTAINS). THE STEADY SHOWERS WILL
CROSS THE AREA A FEW HOURS AHEAD OF THE FRONT... FROM THE EARLY
MORNING PREDAWN HOURS THROUGH MID TO LATE AFTERNOON. ONCE AGAIN AN
ISOLATED STORM OR TWO IS POSSIBLE... PARTICULARLY EAST OF HIGHWAY 1
WHERE SOME EARLY-DAY HEATING AND SLIGHTLY HIGHER SURFACE DEWPOINTS
SHOULD PUSH UP THE RISK OF A FEW HUNDRED J/KG OF CAPE BY THE TIME
THE MAIN RAIN SHIELD ARRIVES... SO WILL GO WITH A SLIGHTLY HIGHER
THUNDER RISK IN THE FAR EAST. BY THIS TIME THE LOW-MID LEVEL WINDS
WILL BE FROM THE SW... FAVORING A LINEAR STRUCTURE TO ANY
CONVECTION... SO A FEW WEAK BOWING SEGMENTS WITH ENHANCED WIND GUSTS
CANNOT BE RULED OUT... BUT THE DECREASING BACKGROUND WINDS AND LOW
LEVEL SHEAR MAGNITUDES WILL LIMIT THE THREAT OF ANY VERY STRONG
WINDS. RAINFALL INTENSITY IS EXPECTED TO DECREASE A BIT AS THE BAND
SHIFTS OUT OF THE MOUNTAINS AND INTO THE PIEDMONT... A FUNCTION OF
THE DROPOFF IN LARGE SCALE LIFT... SO AMOUNTS ARE NOT EXPECTED TO
POSE A FLOODING THREAT. BUT GIVEN THE VIGOROUS LOW LEVEL MOISTURE
TRANSPORT... WE SHOULD STILL EXPECT STORM TOTAL AMOUNTS OF AROUND
1.0-1.5" WHICH MAY LEAD TO MINOR FLOODING IN URBAN AND LOW LYING
AREAS. PRECIP SHOULD BE TAPERING OFF DURING THE MID-LATE
AFTERNOON... WITH POPS GENERALLY ENDING BY 01Z AND CLEARING SKIES
FROM MID EVENING THROUGH THE NIGHT AS THE COLUMN DRIES AND
STABILIZES. HIGHS SHOULD REACH 72-78. LOWS 43-50. -GIH
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 225 PM WEDNESDAY...
FOR THE PERIOD FRIDAY THROUGH SATURDAY...A DRY AIR MASS BUILDS INTO
CENTRAL NORTH CAROLINA WITH AN 850MB THETA-E TROUGH...NEGATIVE K
INDICES...AND PRECIPITABLE WATER VALUES AT OR BELOW A HALF-INCH.
STRONGER UPPER-LEVEL WINDS ARE FORECAST NORTH OF CENTRAL NORTH
CAROLINA...AND WHERE THE GUIDANCE FORECASTS SOME UPPER-LEVEL
MOISTURE THIS RESIDES MAINLY NORTH OF CENTRAL NORTH CAROLINA IN
VICINITY OF THOSE HIGHER WINDS ALOFT. BUFR SOUNDINGS FROM BOTH THE
NAM AND GFS ARE DRY...EVEN AS A WEAK MID-LEVEL WAVE OR TWO MOVES
THROUGH THE AREA IN THE SOUTHWEST FLOW ALOFT.
925MB WINDS ARE NEARLY 30KT AT 12Z FRIDAY IN THE TIGHT GRADIENT
BEHIND THE FRONT...AS HIGH PRESSURE BUILDS EAST. EXPECT SOME BREEZY
CONDITIONS FOR A PART OF FRIDAY WITH MIXING...AND SOME WIND GUSTS
COULD BE BRIEFLY 25 TO 30 MPH PARTICULARLY IN THE INTERSTATE 95
CORRIDOR. THE GRADIENT RELAXES SOME BY FRIDAY NIGHT ALTHOUGH THERE
APPEARS TO BE ENOUGH GRADIENT FOR A LIGHT BUT NOTICEABLE WIND FOR
MUCH OF NIGHT ESPECIALLY EAST OF U.S. 1. THERE SHOULD BE SOME LESSER
GUSTS IN THE TEENS KNOTS EARLY SATURDAY WITH MIXING ACCORDING TO THE
BUFR SOUNDINGS BEFORE WINDS GRADUALLY DIMINISH...WITH POSSIBLY A
LATE-DAY GUST IN THE LOWER TEENS MPH NEAR THE TRIAD AS WINDS BECOME
SOUTHWEST. HIGHS ANTICIPATED FROM 1000-850MB THICKNESSES CORRESPOND
WELL TO THE CONSENSUS OF MAV AND GRIDDED MOS GUIDANCE...THE FORMER
WHICH HAS BEEN DIFFICULT TO BEAT OF LATE...FOR HIGHS IN THE UPPER
50S TO MID 60S FRIDAY AND MAINLY 55 TO 60 SATURDAY AS THICKNESSES
ARE JUST A FEW METERS LOWER THEN. OVERNIGHT LOWS FRIDAY NIGHT IN THE
30S.
FOR THE PERIOD SATURDAY NIGHT THROUGH WEDNESDAY...A SOUTHWEST FLOW
ALOFT CONTINUES EARLY IN THIS PART OF THE LONG-TERM PERIOD WITH A
MID-LEVEL TROUGH APPROACHING AND MOVING THROUGH CENTRAL NORTH
CAROLINA EARLY IN THE NEXT WORK WEEK. AHEAD OF THE TROUGH THE LONG-
TERM GUIDANCE DEVELOPS A WAVE ALONG AND JUST AHEAD OF A FRONTAL
BOUNDARY THAT PASSES THROUGH CENTRAL NORTH CAROLINA SATURDAY NIGHT
INTO SUNDAY...WHILE KEEPING THE SURFACE LOW PRESSURE AND MOST OF ITS
MOISTURE OFFSHORE. THE GFS REMAINS DRY WITH THE FRONTAL
PASSAGE...WHILE THE 12Z ECMWF HAS TRENDED WETTER WITH THE
FRONT...THE FORMER SHOWING STRONGER SURFACE RIDGING AHEAD OF THE
FRONT WHILE THE LATTER WEAKENS THE HIGH MORE WITH A SHARPER TROUGH.
IN ADDITION...BOTH THE GFS AND THE ECWMF TRY TO PROVIDE FOR VERY
MARGINAL QPF...BARELY MEASURABLE...QPF JUST EAST OF CENTRAL NORTH
CAROLINA POST-FRONTAL CLOSER TO LOW PRESSURE OFFSHORE. GIVEN THE DRY
AIR IN PLACE...UNCERTAINTY REGARDING THE ABILITY OF LOW PRESSURE TO
PUSH MOISTURE BACK INTO CENTRAL NORTH CAROLINA...AND THE LOW QPF
WHERE IT DOES EXIST...WILL KEEP PRECIPITATION CHANCES BELOW SLIGHT
FOR NOW AND MONITOR THE LONG-TERM GUIDANCE TRENDS FOR POSSIBLE
ADDITION OF LOW CHANCES ESPECIALLY WITH THE FRONT OVERNIGHT
SATURDAY.
AN UPPER RIDGE BUILDS IN LATE IN THE LONG-TERM PERIOD WHICH SHOULD
HELP TO MODERATE THE AIR MASS. COLDEST TEMPERATURES SHOULD BE SUNDAY
AND SUNDAY NIGHT WITH HIGHS SUNDAY STAYING IN...OR STRUGGLING TO GET
OUT OF...THE 40S AND OVERNIGHT LOWS SUNDAY NIGHT SOLIDLY IN THE 20S
ALMOST AREAWIDE. IT COULD ALSO BE MODESTLY BREEZY WITH MIXING SUNDAY
IN A GRADIENT BETWEEN HIGH PRESSURE TRYING TO BUILD IN AND LOW
PRESSURE OFFSHORE...ADDING A LITTLE TO THE CHILL.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 715 PM WEDNESDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD AS FRONTAL SYSTEM BRINGS HEAVY RAIN AND GUSTY WINDS TO THE
AREA. AS SOME LIGHT RAIN MOVES THROUGH THE COASTAL PLAIN THIS
EVENING...EXPECT SOME PERIODS OF MVFR/IFR VISIBILITIES AT KRWI. THIS
BAND SHOULD EVENTUALLY SHIFT OFF TO THE NORTHEAST...AT WHICH TIME
SOME LIFTING OF THE CEILINGS AND VISIBILITIES COULD OCCUR. ALL OTHER
SITES ARE VFR AT THIS TIME BUT ARE EXPECTED TO EXPERIENCE LOWER
CEILINGS AS PRECIPITATION ASSOCIATED WITH THE FRONT APPROACHES.
EXPECT RAIN TO MOVE INTO THE TRIAD SITES JUST BEFORE 06Z WITH THE
LEADING EDGE OF THE PRECIPITATION MOVING INTO THE KRDU AREA SOMETIME
AFTER 6Z WITH KFAY AND KRWI PRECIPITATION ARRIVAL TIMES CLOSER TO THE
10-12Z TIME FRAME. THE HEAVIEST RAIN AT ALL OF THESE SITES WILL COME
A COUPLE OF HOURS AFTER THE ARRIVAL TIME WITH THE PRECIPITATION
ENDING LATER THURSDAY AFTERNOON/EARLY EVENING. DURING THIS PERIOD
EXPECT IFR CEILINGS WITH TEMPO LIFR CEILINGS POSSIBLE.
IN ADDITION TO PERIODS OF HEAVY RAIN...GUSTY WINDS CAN BE
EXPECTED...WITH SUSTAINED WIND SPEEDS OF 10-15 KTS GUSTING POSSIBLY
AS HIGH AS 25 KTS BUT MORE LIKELY 15-20 KTS AT PERIODS THROUGHOUT
THE NIGHT TONIGHT AND THROUGH THURSDAY AFTERNOON.
LONG TERM: AFTER THE TAF PERIOD EXPECT A RETURN TO VFR CONDITIONS
WITH A VERY SLIGHT CHANCE OF PRECIPITATION WITH A FRONT ON SATURDAY
NIGHT INTO SUNDAY MORNING BUT OTHERWISE DRY CONDITIONS SHOULD
PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...77
SHORT TERM...HARTFIELD
LONG TERM...DJF
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
729 PM EST WED NOV 18 2015
.SYNOPSIS...
SUBSTANTIAL RAINFALL IS EXPECTED ACROSS THE AREA OVERNIGHT AND
THURSDAY. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA THURSDAY
AFTERNOON. CHILLY AND DRY AIR WILL THEN SPILL INTO THE CAROLINAS
OVER THE WEEKEND AND INTO THE MIDDLE OF NEXT WEEK. A FREEZE IS
POSSIBLE EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 700 PM WEDNESDAY...FAST MOVING SHOWERS WILL CONTINUE TO
MOVE ACROSS THE NORTHERN WATERS AND INTO THE CAPE FEAR REGION THIS
EVE. GIVEN THE FLEETING NATURE OF THESE SHOWERS...RAINFALL
AMOUNTS WILL BE LIGHT.
MORE SIGNIFICANT RAINFALL AHEAD OF COLD FRONT ACROSS THE
APPALACHIANS SHOULD BEGIN MOVING INTO OUR WESTERN ZONES LATE EVE.
WE DO EXPECT THE SHOWERS TO ADVANCE ACROSS THE FORECAST AREA
THROUGH THE OVERNIGHT AND EARLY MORNING HOURS OF THU. THE HIGH
RESOLUTION HRRR CONTINUES TO SHOW THE GREATEST COVERAGE ACROSS THE
WESTERN HALF OF THE FORECAST AREA WHERE WE WILL INCLUDE
CATEGORICAL POPS THROUGH TONIGHT.
AN IMPRESSIVE MID LEVEL TROUGH OVER THE CENTRAL CONUS WILL DRIVE
A COLD FRONT TOWARD THE AREA TONIGHT. INCREASING CONVERGENCE
AHEAD OF THE FRONT ALONG WITH ABUNDANT MOISTURE...PWATS WILL BE
AROUND 2 INCHES AS THE PERIOD ENDS...WILL RESULT IN A BAND OF
ROBUST SHOWERS. MID-LEVEL DYNAMICS WILL BE LACKING AS SHORTWAVE
ENERGY PASSES NORTHWEST OF THE AREA. THERE IS ALSO NO STRONG JETTING
ALOFT SO WE DO NOT EXPECT ANY SEVERE WEATHER. INSTABILITY WILL
ALSO BE IN SHORT SUPPLY AND MID-LEVEL LAPSE RATES WILL BE MARGINAL...
AROUND 6 C/KM. INSTABILITY WITHIN THE CHARGE GROWTH ZONE IS ALSO
LIMITED...BUT APPEARS TO BE ENOUGH TO SUPPORT AT LEAST SOME
THUNDER VERY LATE TONIGHT.
WINDS WILL REMAIN GUSTY OVERNIGHT WITH DIRECTION SLOWLY VEERING
FROM SOUTHEAST TO SOUTH AND EVENTUALLY SOUTHWEST LATE. ISOLATED
GUSTS AROUND 20 MPH WILL BE POSSIBLE...ESPECIALLY ALONG THE
IMMEDIATE COAST OVERNIGHT AS SOUNDINGS DO SHOW A 40 KT LOW-LEVEL
JET. ONCE THE CONVECTION STARTS MOVING INTO THE FORECAST AREA
VERY LATE IN THE PERIOD GUSTS WITHIN STRONGER STORMS COULD
APPROACH 40 KT...AS THE STRONGER WINDS JUST ABOVE THE SURFACE MIX
DOWN. HOWEVER VERTICAL PROFILES DO NOT SUGGEST ANY OTHER WIND
ENHANCEMENT SO THINK WORST CASE SCENARIO WOULD BE A GUST AROUND 40
KT WITHIN THE STRONGEST OF STORMS.
COMBINATION OF STRONG SOUTHERLY FLOW AND CLOUD COVER WILL KEEP
LOWS MORE THAN 20 DEGREES ABOVE CLIMO. IN FACT...LOWS TONIGHT
WILL BE HIGHER THAN THE NORMAL HIGH TEMPS FOR THIS DATE.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 PM WEDNESDAY...A WARM FRONT WILL LIFT NORTH OF THE
FORECAST AREA ON THURSDAY MORNING AS A COLD FRONT APPROACHES FROM
THE NW. THIS COLD FRONT WILL MOVE ACROSS THE EASTERN CAROLINAS AND
THEN OFFSHORE THURSDAY EVENING. COOL AND DRY HIGH PRESSURE WILL
BUILD IN ON FRIDAY. THE FRONT WILL BRING EXTENSIVE RAINFALL WITH
ISOLATED THUNDERSTORMS POSSIBLE INTO THURSDAY AFTERNOON. SKIES
WILL CLEAR ON FRIDAY AS THE HIGH BUILDS IN. EXPECTING QPF TOTALS
FOR DAYTIME THURSDAY IN THE 0.50 TO 0.75 INCH RANGE. AIR MASS IN
WAKE OF WARM FRONT ON THURSDAY WILL KEEP TEMPERATURES RUNNING
ABOVE NORMAL WITH DAYTIME HIGHS IN THE MID 70S. POST FROPA COLD
ADVECTION ON FRIDAY WILL KNOCK TEMPERATURES BACK DOWN TO AROUND
CLIMO...WITH HIGHS IN THE MID TO UPPER 60S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 PM WEDNESDAY...HIGH PRESSURE EXTENDING DOWN FROM THE
NORTH WILL WEAKEN AND SHIFT FARTHER OFF SHORE AS A LOW PRESSURE
SYSTEM RIDES ACROSS THE GREAT LAKES INTO CANADA OVER THE WEEKEND.
THIS SYSTEM WILL DRAG A DRY COLD FRONT ACROSS THE CAROLINAS LATE
SATURDAY INTO EARLY SUNDAY...USHERING IN COLD CANADIAN HIGH
PRESSURE FOR EARLY NEXT WEEK. A GRADUAL WARMING TREND WILL FOLLOW
HEADING INTO MID WEEK. SEASONAL TEMPS WILL BEGIN AND END THE LONG
TERM PERIOD WITH 60S ON SATURDAY AND AGAIN ON WED...BUT CHILLY
WEATHER WILL BE SANDWICHED IN BETWEEN.
A DRY AND COOL AIRMASS WILL BE IN PLACE AHEAD OF COLD FRONT ON
SATURDAY. PCP WATER VALUES ACROSS THE AREA WILL BE A HALF INCH OR
LESS SATURDAY MORNING WITH LIGHT NORTHERLY FLOW AT THE SURFACE. A
DEEPER S-SW FLOW WILL RIDE OVER THIS NORTHERLY FLOW AND MAY PRODUCE
SOME CLOUDS AND PCP MAINLY OFF THE COAST...AND MAY REACH UP INTO
PORTIONS OF COASTAL CAROLINAS LATER ON SATURDAY. THIS WILL BE SHORT
LIVED AS A COLD FRONT MOVES THROUGH AND SCOURS OUT ALL MOISTURE
THROUGH SUNDAY. EXPECT PCP WATER VALUES DOWN NEAR A QUARTER OF AN
INCH BY SUNDAY EVENING. OVERALL EXPECT A COLD CANADIAN AIR MASS TO
SETTLE INTO THE AREA REINFORCING A MAINLY DRY AND COLD AIR MASS
THROUGH EARLY NEXT WEEK. AS MID TO UPPER TROUGH SHIFTS OFF SHORE
THROUGH EARLY MONDAY DEEP COLD AND DRY AIR WILL KEEP TEMPS POSSIBLY
BELOW FREEZING AND NOT MAKING IT PAST 50 ON MONDAY IN CONTINUED
CAA...EVEN WITH BRIGHT SUNSHINE ALL DAY.
ONCE THE HIGH PRESSURE REACHES OVERHEAD LATE MONDAY INTO EARLY
TUES...CAA WILL CUT OFF BUT MORE IDEAL RADIATIONAL COOLING WILL
DEVELOP MON NIGHT. 850 TEMPS AROUND 7-8C SAT MAY DROP AS LOW AS -4C
OVERNIGHT SUNDAY. THEREFORE MAY SEE TEMPS BELOW FREEZING BOTH MONDAY
AND TUES MORNING. THIS MAY END THE GROWING SEASON ACROSS MOST...IF
NOT ALL ZONES EARLY NEXT WEEK. FOR NOW HAVE TRENDED COLDER BOTH
MORNINGS WITH BELOW FREEZING TEMPS EXCEPT ALONG THE COAST.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 00Z THURSDAY...FORECAST ON TRACK WITH THE THE MAIN FOCUS
BEING THE STRONGLY FORCED CONVECTIVE LINE/SWATH NOW ENTERING THE
WESTERN CAROLINAS. VFR CONDITIONS DETERIORATE TO IFR FROM WEST TO
EAST BEGINNING AROUND 0600 UTC IN LBT AND FLO. SOME UNCERTAINTY
EXISTS ABOUT THE STRENGTH OF THE LINE AS IT APPROACHES THE COAST
AROUND 0900 UTC AND THEREFORE JUST ADDRESSED WITH MVFR. DEPENDING
ON LATER GUIDANCE MAY INCREASE THREAT TO IFR.PRECIP. ENDS FROM
WEST TO EAST LATER THURSDAY BUT LOW CLOUDS WILL LINGER FOR A WHILE
LONGER.
EXTENDED OUTLOOK...MVFR/IFR LIKELY INTO THURSDAY NIGHT DUE TO LOW
CLOUDS/RAIN ALONG WITH A COLD FRONTAL PASSAGE. OTHERWISE EXPECT
VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 700 PM WEDNESDAY...PINCHED GRADIENT AHEAD OF ADVANCING COLD
FRONT WILL MAINTAIN STRONG SOUTHERLY FLOW THROUGH THE PERIOD.
SOUTHEAST WINDS WILL SLOWLY VEER TO SOUTH AND THEN SOUTHWEST
AFTER MIDNIGHT. GRADIENT WILL REMAIN SUPPORTIVE OF WINDS AROUND 20
KT THROUGH THE PERIOD WITH POTENTIAL FOR GUSTS APPROACHING 30 KT
AT TIMES. STRONG LOW LEVEL JET WILL HELP ENHANCE WIND GUSTS...BUT
WARM ADVECTION OVER COOLER SEA SURFACE TEMPERATURES WILL LIMIT
MIXING AND DO NOT THINK GALE FORCE GUSTS WILL BE AN ISSUE. SEAS
WILL CONTINUE RUNNING 5 TO 8 FT WITH POTENTIAL FOR ISOLATED DOUBLE
DIGITS SEAS NEAR FRYING PAN SHOALS.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 PM WEDNESDAY...SMALL CRAFT ADVISORY WILL BE IN EFFECT
AT THE BEGINNING OF THE PERIOD WITH ATTENDANT CONDITIONS LIKELY
PERSISTING WELL INTO FRIDAY. A WARM FRONT WILL LIFT NORTH OF THE
WATERS ON THURSDAY MORNING AS A COLD FRONT APPROACHES FROM THE NW.
THIS COLD FRONT WILL MOVE OFFSHORE THURSDAY EVENING AND WILL MOVE
WELL EAST OF THE WATERS ON FRIDAY. IN ADDITION TO SEAS IN THE 6 FT
RANGE THROUGH MUCH OF THE PERIOD...THE FRONT WILL BRING EXTENSIVE
RAINFALL WITH ISOLATED THUNDERSTORMS INTO THURSDAY AFTERNOON.
SKIES WILL CLEAR ON FRIDAY.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 330 PM WEDNESDAY...WINDS WILL BASICALLY REMAIN OUT OF THE
NORTH THROUGH THE PERIOD WITH SHORTER PERIOD WIND WAVES DOMINATING
THE SEAS. HIGH PRESSURE EXTENDING DOWN FROM THE NORTH WILL WEAKEN
THROUGH SATURDAY AS DRY COLD FRONT MAKES ITS WAY EAST. THEREFORE NE
WINDS UP AROUND 10 KT ON SATURDAY MAY BECOME MORE VARIABLE AND
LIGHTER LATE SATURDAY AHEAD OF COLD FRONT BUT WILL BACK TO THE
N-NW BY SUNDAY AS COLD CANADIAN HIGH PRESSURE BUILDS IN BEHIND
COLD FRONT.
SEAS AROUND 2 TO 4 FT ON SATURDAY WILL INCREASE IN NORTHERLY SURGE
BEHIND COLD FRONT BUT N-NW DIRECTION WILL KEEP HIGHEST SEAS IN OUTER
WATERS. EXPECT WINDS TO INCREASE TO 15 TO 20 KT SUN INTO EARLY
MONDAY WITH SEAS INCREASING UP NEAR SCA THRESHOLDS IN OUTER WATERS
SUN NIGHT INTO EARLY MONDAY WITH GREATEST CAA. ONCE HIGH PRESSURE
SHIFTS CLOSER OVERHEAD LATE MONDAY...WINDS AND SEAS SHOULD SETTLE
DOWN A BIT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST FRIDAY FOR AMZ250-252-254-
256.
&&
$$
NEAR TERM...RJD
SHORT TERM...REK
LONG TERM...RGZ
AVIATION...SHK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1135 PM CST MON NOV 16 2015
.UPDATE...
ISSUED AT 1135 PM CST MON NOV 16 2015
LATEST WATER VAPOR IMAGERY SHOWS A SOUTHWEST FLOW INTO NORTH
DAKOTA AS A PLUME OF MOISTURE ASSOCIATED WITH A SOUTHERN STREAM
UPPER LOW ACROSS THE FOUR CORNERS CONTINUES TO SHIFT EAST.
REGIONAL RADAR SHOWS SHOWERS IN SOUTHEAST SOUTH DAKOTA MOVING
NORTH WITH TIME...AND THIS IS PROJECTED TO AFFECT OUR FAR
SOUTHEAST COUNTIES OF LAMOURE AND DICKEY 10Z-18Z TUESDAY.
OTHERWISE...A NORTHERN STREAM SHORTWAVE LOCATED OVER NORTH
CENTRAL MONTANA INTO CENTRAL SASKATCHEWAN WILL REACH OUR WESTERN
BORDER 12Z-15Z TUESDAY...THEN CROSS THROUGH CENTRAL NORTH DAKOTA
DURING THE AFTERNOON. CURRENT CLEARING PER FOG/STRATUS LOOP
LOCATED NEAR OUR WESTERN BORDER AND PER LATEST HRRR...WILL
GRADUALLY SHIFT EAST OVERNIGHT INTO TUESDAY AS THE AFOREMENTIONED
NORTHERN STREAM UPPER TROUGH SHIFTS EAST. DRIZZLE STILL POSSIBLE
REST OF TONIGHT...BUT PATCHY AT BEST. SUNSHINE TO FOLLOW BEHIND
THE TROUGH FROM WEST TO EAST TUESDAY. CURRENT GRIDDED FORECAST HAS
THE ABOVE FORECAST ELEMENTS HANDLED WELL AT THIS TIME.
UPDATE ISSUED AT 840 PM CST MON NOV 16 2015
QUITE A FEW REPORTS ON FACEBOOK THIS EVENING OF DRIZZLE ACROSS
NORTHWEST AND NORTH CENTRAL NORTH DAKOTA...BUT ALSO EXTENDING
INTO THE SOUTHWEST...THANKS! LATEST 00 UTC RAP SOUNDINGS DO
SUPPORT SOME DRIZZLE SPREADING EAST ACROSS THE FORECAST AREA
TONIGHT AND HAVE EXTENDED THE AREA OF DRIZZLE INTO THE SOUTHWEST
AND SOUTH CENTRAL. FOR THE MOST PART CRITICAL SURFACE TEMPERATURES
REMAIN ABOVE FREEZING WHILE THE DRIZZLE IS FALLING SO AT THIS
TIME THERE DOES NOT APPEAR TO BE A SIGNIFICANT RISK OF FREEZING
DRIZZLE. WITH THAT BEING SAID...THE NORTHWEST IS FORECAST TO DROP
TO NEAR OR SLIGHTLY BELOW FREEZING LATE THIS EVENING. SOME
UNTREATED ROADS AND SIDEWALKS COULD BECOME SLIPPERY. DRIER AIR
WORKS INTO THE LOWER ATMOSPHERE FROM WEST TO EAST AFTER
MIDNIGHT...WHICH SHOULD END THE THREAT OF DRIZZLE.
EXCEPT FOR THE FAR NORTHWEST...IT APPEARS THE DRIZZLE SHOULD END
BEFORE TEMPERATURES FALL BELOW FREEZING. WILL CERTAINLY NEED TO
MONITOR BUT AT THIS TIME WE DO NOT SEE A SIGNIFICANT IMPACT DUE TO
FREEZING DRIZZLE. ALSO...ANY WET SURFACES IN THE WEST THAT DO NOT
COMPLETELY DRY OFF COULD BECOME ICY DUE TO TEMPERATURES FALLING
INTO THE 20S TOWARD MORNING...EVEN THOUGH THE FREEZING DRIZZLE
WILL HAVE ENDED.
UPDATE ISSUED AT 630 PM CST MON NOV 16 2015
SURFACE COLD FRONT HAS MOVED FROM WESTERN INTO CENTRAL NORTH
DAKOTA THIS EVENING. BEHIND THE COLD FRONT 3-5 MB PRESSURE RISES
OVER MOST OF WESTERN NORTH DAKOTA AND CURRANT GUSTS OF 25 TO 35
MPH. WILL BUMP UP THE WINDS ACROSS WESTERN NORTH DAKOTA THIS
EVENING AND IN THE CENTRAL LATE EVENING INTO THE EARLY OVERNIGHT
HOURS. WINDS WILL REMAIN BELOW ADVISORY CRITERIA. LATEST RADAR IS
SHOWING A FEW VERY WEAK RETURNS OVER THE SOUTHWEST INTO SOUTH
CENTRAL...AND ANOTHER AREA OVER NORTHEAST MONTANA MOVING INTO THE
FAR NORTHWEST IN AN HOUR OR TWO. NO GROUND TRUTH FROM EITHER AREA
AS OF YET. ALSO GOT A REPORT OF SOME DRIZZLE NEAR GARRISON. CAN
SEE SOME VERY LIGHT REFLECTIVITIES BEHIND THE COLD FRONT MOVING
INTO THE MINOT AREA. WILL LIKELY ADD A MENTION OF DRIZZLE OVER THE
NORTHWEST/NORTH CENTRAL THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 236 PM CST MON NOV 16 2015
IMPACTS FROM LOW LEVEL STRATUS HIGHLIGHT THE SHORT TERM FORECAST.
AS OF 20 UTC...A COLD FRONT HAS PROPAGATED THROUGH THE US HIGHWAY
85 CORRIDOR...AND WILL CONTINUE TO PROGRESS EAST INTO THE EVENING.
BREEZY POST-FRONTAL CONDITIONS ARE FORECAST INTO THE EVENING.
WHILE THE STRATUS DECK FROM THIS MORNING CONTINUES TO ERODE ACROSS
THE AREA...A SECONDARY DECK BEHIND THE COLD FRONT WILL SOON ENTER
THE WEST...AND ALSO SPREAD EAST THROUGH THE EVENING BEHIND THE
COLD FRONT. GIVEN A CONSENSUS OF THE 12 UTC DETERMINISTIC AND
ENSEMBLE SUITES AND THE 17-19 UTC HRRR ITERATIONS...LOCATIONS WEST
OF US HIGHWAY 83 ARE EXPECTED TO CLEAR LATE TONIGHT...SUPPORTING
LOWS IN THE 20S...WITH 30S ELSEWHERE. THERE IS A CHANCE OF RAIN
TONIGHT ACROSS THE JAMES RIVER VALLEY ASSOCIATED WITH A SHORTWAVE
EJECTING NORTHEAST OUT OF THE UPPER LEVEL LOW ACROSS THE SOUTHWEST
CONUS.
FOR TUESDAY...STRATUS IS EXPECTED TO CONTINUE TO CLEAR
CENTRAL...WITH COOLER POST FRONTAL TEMPERATURES IN THE 40S.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 236 PM CST MON NOV 16 2015
THE MAIN FOCUS FOR THE LONG TERM IS HIGH WINDS AND POTENTIAL
CRITICAL FIRE WEATHER CONDITIONS.
A DEEP...CLOSED LOW WILL PROPAGATE ACROSS THE MOUNTAIN WEST AND
ENTER THE NORTHERN PLAINS LATE TUESDAY. THIS LOW WILL PHASE WITH A
CLIPPER COMING ACROSS SOUTHERN CANADA WEDNESDAY. THIS WILL LIKELY
LEAD TO A RAPID TIGHTENING OF THE PRESSURE GRADIENT AND
ENHANCEMENT OF THE WIND FIELDS AT ALL LEVELS. A COLD FRONT IS
FORECAST TO SWING THROUGH NORTH DAKOTA WEDNESDAY
MORNING/AFTERNOON. AHEAD OF THE FRONT TEMPERATURES ARE EXPECTED TO
CLIMB INTO THE 40S. THIS WILL ALLOW RELATIVE HUMIDITY VALUES TO
DROP INTO THE 30S ACROSS PORTIONS OF THE SOUTHWEST AND SOUTH
CENTRAL NORTH DAKOTA. BEHIND THE FRONT...VERY STRONG NORTHWEST
WINDS AROUND 40 MPH...WITH GUSTS TO 60 MPH ARE LIKELY. THE 12 UTC
MODEL SUITE OF THE GFS/ECMWF/CANADIAN/NAM ALL INDICATE A VERY WELL
MIXED BOUNDARY LAYER WITH STEEP LAPSE RATES AND STRONG COLD AIR
ADVECTION. THEREFORE...A HIGH WIND WATCH WAS ISSUED. DUE TO THE
RELATIVELY SLOW PROGRESSION OF THE LOWS AFTER THEY PHASE...A TIGHT
PRESSURE GRADIENT AND STRONG WINDS WILL LIKELY EXIST THROUGH
THURSDAY MORNING. WINDS...COMBINED WITH RELATIVELY LOW HUMIDITY
AND DRY GRASSLANDS COULD LEAD TO CRITICAL FIRE CONDITIONS
WEDNESDAY. A FIRE WEATHER WATCH WAS ISSUED AFTER COORDINATING WITH
LOCAL FIRE MANAGERS FOR LOCATIONS SOUTH OF HIGHWAY 2 AND 52.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1135 PM CST MON NOV 16 2015
THE LATEST 06Z SATELLITE IMAGERY AND SURFACE OBSERVATIONS SHOWS
MVFR CIGS OCCURRING AT THE TERMINALS...WITH THE EXCEPTION OF KMOT
WHICH IS IFR/900FT CIGS...AND KJMS WHICH IS VFR/4300FT. TREND
THROUGH 13Z TUESDAY IS FOR CIGS TO BECOME VFR FROM WEST TO EAST UP
THORUGH A KMOT TO KBIS LINE. KJMS IS FORECAST TO DROP INTO THE
MVFR RANGE BY 10Z TUESDAY AND REMAIN THERE UNTIL 18Z. GUSTY
NORTHWEST WINDS TO 30 MPH WILL CONTINUE THROUGH TUESDAY MORNING
THEN BEGIN TO WEAKEN FROM WEST TO EAST.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY
EVENING FOR NDZ017>023-025-031>037-040>048-050-051.
HIGH WIND WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY MORNING
FOR NDZ001>005-009>013-017>023-025-031>037-040>048-050-051.
&&
$$
UPDATE...KS
SHORT TERM...AYD
LONG TERM...AJ
AVIATION...KS
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
913 AM EST TUE NOV 17 2015
.SYNOPSIS...
LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS TODAY AS
MOISTURE BEGINS TO INCREASE OVER THE OHIO VALLEY. AHEAD OF A COLD
FRONT...RAIN WILL DEVELOP OVER THE REGION ON WEDNESDAY. MUCH
COOLER CONDITIONS ARE EXPECTED FOR THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADAR AND SURFACE OBSERVATIONS INDICATE THAT PRECIPITATION HAS
MOVED INTO THE SOUTHWEST COUNTIES. FURTHER NORTH AND EAST ECHOES
ARE LIGHTER AND ANY PRECIPITATION IS REMAINING SPRINKLES FOR NOW
AS LOW LEVELS REMAIN DRY.
RECENT RAP AND HRRR RUNS SUGGEST THAT THE PRECIPITATION WILL
CONTINUE NORTH BUT CHANCE OF MEASURABLE WILL DECREASE INTO THE
AFTERNOON. SO POPS HAVE BEEN ADJUSTED ACCORDINGLY. FORECAST HIGHS
LOOK IN THE BALLPARK AT THIS POINT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
AFTER A DRY STRETCH ON TUESDAY NIGHT...ATTENTION WILL TURN TO THE
CENTRAL PLAINS...WHERE A STACKED AREA OF LOW PRESSURE WILL BE
MOVING VERY SLOWLY OVER KANSAS. THIS WILL CHANGE IN A HURRY...AS
INTERACTION WITH A LARGE TROUGH JUST EAST OF THE CANADIAN ROCKIES
WILL INITIATE SOME PHASING...WITH THE PLAINS LOW OPENING UP
RAPIDLY AS IT ACCELERATES TO THE NORTH-NORTHEAST (WITH A STRONGER
SURFACE LOW DEVELOPING FAR TO THE NORTH). AS THE RESULTANT TROUGH
MOVES TOWARD THE OHIO VALLEY...IT WILL BE SHORT ON PROGRESSIVE
(EASTWARD) MOTION...LEADING TO A FAIRLY SLOW MOVEMENT ACROSS THE
ILN FORECAST AREA.
THE MAIN BAND OF PRECIPITATION THAT WILL IMPACT THE REGION WILL BE
FORCED BY LARGE-SCALE ASCENT FROM UPPER DIFFLUENCE AHEAD OF THE
TROUGH...AND A NARROW BAND OF MOISTURE CONVERGENCE WITHIN THE
PLUME OF HIGHER PWAT/THETA-E VALUES THAT WRAPS INTO THE
NEWLY-DEVELOPING SURFACE LOW THAT WILL BE MOVING NORTHWARD
THROUGH MINNESOTA. IT WOULD BE MISLEADING TO SUGGEST THAT THE
PRIMARY BAND OF PRECIPITATION WILL BE FOCUSED ALONG OR JUST AHEAD
OF THE ACTUAL COLD FRONT...WHICH THETA-E AND WIND MAPS SUGGEST
WILL REMAIN WELL BEHIND. WITH HIGH CONFIDENCE IN TIMING AND
PLACEMENT OF THE PRECIPITATION...POPS HAVE BEEN INCREASED TO
100-PERCENT...MOVING ACROSS THE ILN FORECAST AREA BETWEEN 15Z AND
00Z.
CONVECTIVE POTENTIAL WITH THIS SYSTEM CONTINUES TO APPEAR VERY
LOW...AND THUNDER HAS NOT BEEN INCLUDED IN THE FORECAST...OWING TO
SOUNDINGS THAT SUPPORT ONLY MINUTE AMOUNTS OF INSTABILITY (AND
NONE DEEP ENOUGH TO PRODUCE LIGHTNING). GFS SOUNDINGS DEPICT
SLIGHTLY STEEPER LAPSE RATES IN THE LOWEST FEW THOUSAND FEET THAN
NAM SOUNDINGS...BUT IN EITHER CASE...EXTREMELY POOR LAPSE RATES
JUST ABOVE 5KFT WILL LIMIT THE POTENTIAL FOR CONVECTIVE ELEMENTS
WITHIN THE BAND OF RAIN. THERE IS ALWAYS GOING TO BE SOME NATURAL
CONCERN FOR STRONG WINDS (AND SOMETIMES SEVERE WEATHER) WHEN WIND
SHEAR IS AS STRONG AS IT WILL BE WITH THIS SYSTEM. INDEED...THE
RAW MAGNITUDE OF THE SHEAR IS IMPRESSIVE. IN THIS CASE IT IS
LIKELY TO BE A MOSTLY-IRRELEVANT FOOTNOTE ON THE FORECAST...DUE
TO ITS ORIENTATION TO THE PRECIPITATION (ALMOST COMPLETELY
PARALLEL NORTH-TO-SOUTH) AND THE LACK OF NEAR-SURFACE FORCING.
THIS SETUP IS NOT ONE THAT FAVORS STRONGLY FOCUSED OR ORGANIZED
SURFACE-ROOTED PRECIPITATION...WITH EXTREMELY MERIDIONAL FLOW
THROUGH THE TROPOSPHERE...AND SLOW EASTWARD PROGRESSION OF THE
FORCING THAT IS PRESENT. THIS IS NOT TO SAY THAT SOME GUSTY WINDS
MIGHT NOT BE REALIZED. A SLIGHT INVERSION SHOULD KEEP WINDS FROM
GETTING TOO STRONG LATE TUESDAY NIGHT INTO EARLY WEDNESDAY
MORNING...BUT ANY SLIGHT MIXING ON WEDNESDAY WILL ALLOW FOR GUSTS
IN THE 25-30 KNOT RANGE...WHETHER WITHIN OR OUTSIDE OF RAIN.
SPEAKING OF THE RAIN...MODEL SOUNDINGS SUGGEST THAT THE ATMOSPHERE
WILL BECOME QUITE MOIST...WITH PRECIPITABLE WATER VALUES THAT WILL
APPROACH AN INCH AND A HALF. VALUES THAT HIGH WOULD BE NEAR RECORD
FOR MID-NOVEMBER (BASED ON SPC SOUNDING CLIMATOLOGY FOR ILN/DAY).
HOWEVER...THIS PLUME OF MOISTURE WILL BE NARROW...AND NOT SUBJECT
TO STRONG OR FOCUSED FORCING. THUS...PRECIPITATION AMOUNTS ARE
LIKELY TO RANGE FROM AROUND AN INCH IN THE SOUTHWESTERN CWA TO A
HALF INCH IN THE NORTHEASTERN CWA.
TEMPERATURES ON WEDNESDAY WILL BE HEAVILY INFLUENCED BY
PRECIPITATION. THE SOUTHEASTERN CWA...WHICH WILL REMAIN DRY THE
LONGEST...MAY WELL SNEAK INTO THE 70S AS A RESULT OF THE
STRENGTHENING WARM ADVECTION. ONCE THE SURFACE COLD FRONT FINALLY
PASSES THROUGH ON WEDNESDAY NIGHT...TEMPERATURES WILL BEGIN TO
FALL...AND CONDITIONS WILL DRY OUT CONSIDERABLY. A WEAK SECONDARY
FRONT ON THURSDAY WILL ALLOW FOR ANOTHER PUSH OF COLD ADVECTION
TO BEGIN...WITH LITTLE MOISTURE TO SUPPORT MUCH MORE THAN A SLIGHT
CHANCE OF SOME ADDITIONAL CLOUDS (AND NO PRECIPITATION). IF THIS
SECONDARY FRONT COMES THROUGH SLOWER (AS INDICATED BY THE
ECMWF)...TEMPERATURES ON THURSDAY MIGHT BE SEVERAL DEGREES WARMER
THAN THE LOWER-TO-MID 50S CURRENTLY IN THE FORECAST.
DRY CONDITIONS ARE EXPECTED TO CONTINUE ON FRIDAY...AS COOL
SURFACE HIGH PRESSURE MOVES INTO THE REGION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
DRY CONDITIONS WILL CONTINUE INTO FRIDAY AS THE SURFACE HIGH
BEGINS TO PUSH OFF TO THE EAST AND THE LOW LEVEL FLOW BEGINS TO
BACK. THIS IS AHEAD OF SOME SHORT WAVE ENERGY THAT WILL DROP DOWN
ACROSS THE WESTERN GREAT LAKES AND INTO THE UPPER OHIO VALLEY
HEADING INTO THE WEEKEND. THERE CONTINUES TO BE SOME MODEL
DIFFERENCES THOUGH WITH THIS FEATURE AS THE 12Z GFS IS ABOUT 6-12
HOURS FASTER AND A LITTLE FARTHER SOUTH THAN THE 12Z ECMWF. AT ANY
RATE...IT LOOKS LIKE THIS SHOULD AT LEAST SUPPORT SOME LOWER
CHANCE POPS...LATER FRIDAY NIGHT AND INTO SATURDAY AND WILL TREND
THE TIMING TOWARD A BLEND OF THE GFS/ECMWF. PTYPE WILL BE
DEPENDENT ON THE EXACT TIMING OF THIS SYSTEM...BUT IT DOES LOOK
LIKE THE LOW LEVELS MAY BE COULD ENOUGH TO SUPPORT AT LEAST A
RAIN/SNOW MIX WITH ANY PCPN...ESPECIALLY ACROSS NORTHWEST PORTIONS
OF OUR FA. A SECONDARY SHOT OF COLDER AIR WILL THEN SETTLE INTO
OUR AREA THROUGH THE END OF THE LONG TERM PERIOD WITH HIGHS INTO
EARLY NEXT WEEK EXPECTED TO ONLY BE IN THE 40S.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
AS AN UPPER LEVEL LOW PIVOTS NORTHEAST INTO THE CENTRAL PLAINS
TODAY...DOWNSTREAM UPPER RIDGING WILL SHARPEN ACROSS THE EASTERN
GREAT LAKES SOUTHWARD INTO THE SOUTHEAST UNITED STATES. AS THIS
OCCURS...AN EMBEDDED DISTURBANCE AND ASSOCIATED LOW LEVEL JET WILL
PIVOT NORTH/NORTHEAST ACROSS THE MIDDLE OHIO VALLEY NORTHWARD INTO
THE SOUTHERN GREAT LAKES. OUR FORECAST AREA WILL BE ON THE FRINGE OF
THIS STRONGER FORCING/DEEPER MOISTURE. AT THIS TIME...IT APPEARS
THAT SOME LIGHT SHOWER ACTIVITY WILL PIVOT ACROSS THE WESTERN TAF
SITES TODAY...WITH EASTERN SITES SEEING SPRINKLES. CEILINGS AND
VISIBILITIES SHOULD STILL REMAIN VFR.
FOR TONIGHT...UPPER LEVEL LOW WILL CONTINUE ITS MOVEMENT TOWARD
THE NORTHEAST. A SLOW MOVING COLD FRONT IN ASSOCIATION WITH THIS
ENERGY WILL MOVE TOWARD THE EAST. DEEP MOISTURE OUT OF THE GULF OF
MEXICO ALONG WITH STRONG LOW LEVEL CONVERGENCE WILL BRING A BAND
OF SHOWERS TO THE TAF SITES ON WEDNESDAY. IN THE INTERIM...THE
SURFACE PRESSURE GRADIENT WILL INCREASE AS WELL AS THE APPROACH OF
A 75 TO 80 KNOT LOW LEVEL JET. CEILINGS WILL LIKELY RISE TO
HEIGHTS OF JUST CIRRUS/HIGH AC AHEAD OF THE FRONT BEFORE
CONDITIONS DETERIORATE WITH THE FRONT ON WEDNESDAY. GIVEN SUCH A
STRONG LOW LEVEL JET...AND WITH WINDS FORECAST TO INCREASE FROM
THE SOUTH BETWEEN 50 AND 60 KNOTS AT 2000 FEET...HAVE PLACED THE
THREAT OF LLWS IN THE TAFS.
OUTLOOK...MVFR CEILINGS AND MVFR/IFR VISIBILITIES ARE LIKELY
ACROSS ALL SITES WITH RAIN WEDNESDAY AND WEDNESDAY NIGHT. LLWS
LIKELY ON WEDNESDAY AS WELL.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...
SHORT TERM...HATZOS
LONG TERM...JGL
AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS PORTLAND OR
905 AM PST TUE NOV 17 2015
.SYNOPSIS...A MOIST FRONTAL BOUNDARY ACROSS WESTERN WASHINGTON THIS
MORNING WILL SINK SOUTH AS A COLD FRONT LATE THIS AFTERNOON AND
TONIGHT. THERE WILL BE A BREAK IN THE ACTIVE WEATHER PATTERN LATE
TONIGHT AND WEDNESDAY...BUT THE NEXT MILD AND MOIST SYSTEM IS
EXPECTED TO BRING ANOTHER ROUND OF HEAVY RAINFALL TO NORTHWEST OREGON
WEDNESDAY NIGHT. WEAK HIGH PRESSURE ALOFT SETS UP THURSDAY NIGHT AND
FRIDAY.
&&
.SHORT TERM...MOIST CONVEYOR BELT CONTINUES TO BE DIRECTED AT WESTERN
WASHINGTON AND NORTHWEST OREGON THIS MORNING. KAST PROFILER DATA
INDICATES PRECIPITABLE WATER VALUES 1.1 TO 1.2 INCHES AS OF 16Z.
IMPRESSIVE RAINFALL RATES IN SW WA AND THE NORTH OREGON COAST AND
COAST RANGE LAST EVENING...WITH SOME SPOTS SHOWING SEVERAL HOURS OF
0.3 TO 0.5 INCH PER HOUR RAINFALL. HIGHER RESOLUTION MODELS SUCH AS
THE HRRR AND RAP WERE WOEFULLY UNDERDONE ON THE PRECIP. KAST PROFILER
DATA ALSO SHOWS SNOW LEVELS AROUND 7000 FT THIS MORNING.
MODELS STILL HAVE THE WARM FRONT LIFTING A BIT MORE NORTH THIS
MORNING AND EARLY AFTERNOON...WITH THE HEAVIEST PRECIP PUSHED INTO SW
WASHINGTON. 850 MB WEST FLOW OF 40-60 KT INTO THE HIGHER TERRAIN WILL
PROVIDE VERY EFFICIENT OROGRAPHIC LIFT TO THE HIGHER TERRAIN IN SW
WA. THE MOIST BAROCLINIC ZONE FINALLY SAGS SOUTH AS A COLD FRONT LATE
THIS AFTERNOON AND TONIGHT. MODELS SHOW THE LEADING EDGE OF THE 850
MB THERMAL GRADIENT AND 1000-700 MB THICKNESS PACKING REACHING THE S
WA COAST LATE THIS AFTEROON...THEN PUSHING TO THE CENTRAL COAST AND
SOUTH INTERIOR VALLEYS BY MIDNIGHT. MODEL QPF FOR LATE THIS AFTERNOON
AND EVENING SHOW VARYING SOLUTIONS. GFS HAS A 1.5 TO 2.0 INCH 6-HR
BULLSEYE OVER THE S WA CASCADES IN THE 18Z-00Z PERIOD...FOLLOWED BY
1.5 TO 2.0 INCH 6-HR CORE OVER THE N OREGON CASCADES AND FOOTHILLS
00Z-06Z WED. QPF GRIDS HAVE BEEN ADJUSTED. CURRENT FLOOD WATCH FOR NW
OREGON LOOKS GOOD...BUT MAY SEE A COUPLE MORE RIVERS REACH FLOOD ONCE
NEW RIVER FORECASTS ARE OUT.
THE SURFACE PRESSURE GRADIENT WILL TIGHTEN TODAY AND EXPECT STRONG
WIND THROUGH THIS EVENING. THE STRONGEST GUSTS ARE EXPECTED FOR THE
COAST...COAST RANGE AND THE CASCADES MID TO LATE AFTERNOON THROUGH
THE EARLY EVENING. THE HIGH WIND WARNING CONTINUES FOR THE S WA AND N
OREGON COAST...THE WILLAPA HILLS AND N OREGON COAST RANGE. MAY ALSO
GET A FEW GUSTS TO 60 MPH ON THE CENTRAL OREGON COASTAL HEADLANDS
LATE THIS AFTERNOON...BUT SHOULD NOT BE WIDESPREAD ENOUGH TO WARRANT
A WARNING. PEAK WIND PERIOD APPEARS TO BE FROM AROUND 21Z THROUGH 02Z
WED. BESIDES STRONG GUSTY WINDS...BEACHES WILL HAVE THE ADDITIONAL
HAZARD OF DANGEROUS BREAKING WAVES. THOSE PLANNING ON HEADING TO THE
BEACH DURING BREAKS IN THE RAIN MAY WANT TO KEEP THEIR DISTANCE FROM
THE WATERS EDGE.
THE COLD FRONT FINALLY SHIFTS TO SOUTHERN OREGON OVERNIGHT. BY THE
TIME SNOW LEVELS DROP BACK DOWN TO CASCADE PASS LEVELS...THE BULK OF
THE PRECIP WILL HAVE ALREADY OCCURRED. THUS...NOT EXPECTING SNOW
ADVISORY CRITERIA TO BE MET. ANOTHER MOIST WARM FRONT WILL APPROACH
WEDNESDAY AFTERNOON FOR ADDITIONAL RAIN WEDNESDAY NIGHT AND THURSDAY.
THE SNOW LEVELS WILL BE SLOW TO RISE AHEAD OF THE FRONT AND EXPECT A
QUICK BURST OF SNOW FOR THE CASCADE PASSES AS THE MOISTURE FIRST
REACHES THE CASCADES WEDNESDAY NIGHT. THE SNOW LEVELS SHOULD RISE
ABOVE 6000 FEET EARLY THURSDAY MORNING...WITH A POSSIBLE DELAY FOR
THE WASHINGTON CASCADES.
THIS SYSTEM IS VERY MOIST AS SATELLITE DERIVED PRECIPITABLE WATERS
NEAR THE ORIGIN POINT ARE AROUND 2 INCHES...WHICH IS THE HIGHEST WE
HAVE SEEN FROM THE RECENT ATMOSPHERIC RIVER EVENTS. THE PRECIPITABLE
WATER WILL DECREASE AS THE FRONT NEARS THE COAST...BUT THERE IS GREAT
POTENTIAL FOR ANOTHER ROUND OF HEAVY RAIN. EXPECT 1 TO 3 INCHES OF
RAIN FOR THE COAST...COAST RANGE AND THE CASCADES WEDNESDAY EVENING
THROUGH THURSDAY EVENING...AND 0.75 TO 1.25 INCH FOR THE INTERIOR LOW
LANDS. THE MAIN DIFFERENCE WITH THIS SYSTEM IS THAT THE MOISTURE CORE
IS AIMED MORE AT NORTHWEST OREGON INSTEAD OF WESTERN WASHINGTON.
MODELS FORECAST THAT THE BAROCLINIC ZONE WILL MOVE RATHER QUICKLY
ACROSS THE AREA...WITH RAIN ENDING THURSDAY EVENING. THIS WILL HELP
LIMIT THE RAINFALL TOTALS AND FLOODING POTENTIAL. IT ALSO LOOKS LIKE
THE AREA OF HEAVIEST RAIN WILL BE ACROSS NW OREGON RATHER THAN SW
WASHINGTON. THE RIVERS TO THE SOUTH HAVE TAKEN LESS OF A BEATING THE
PAST WEEK THAN WASHINGTON...IN REGARDS TO RAIN TOTALS...AND THIS MAY
ALSO HELP REDUCE FLOODING CONCERNS. RAIN WILL DECREASE THURSDAY NIGHT
WITH DRY WEATHER LIKELY FRIDAY. WEISHAAR
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...THURSDAY NIGHT
THROUGH MONDAY...A SHORTWAVE MOVES QUICKLY ACROSS THE AREA FRIDAY
BRINGING ANOTHER CHANCE FOR RAIN...THOUGH LIKELY NOT VERY MUCH. SNOW
LEVELS WILL BE DOWN AROUND 4000 TO 6000 FT...SO THE PASSES MAY SEE
ANOTHER INCH OR TWO OF SNOW. BEYOND FRIDAY...THE GFS BUILDS HIGH
PRESSURE OVER THE AREA KEEPING US DRY THROUGH THE WEEKEND...WHILE THE
ECMWF IS A LITTLE SLOWER MOVING THE SHOWERS OUT OF OUR AREA AND KEEPS
A CHANCE OF RAIN THROUGH SATURDAY. BY SUNDAY AT THE LATEST...WE
SHOULD BE DRY WITH HIGH PRESSURE OVER THE AREA. TEMPERATURES WILL
COOL DOWN AS WELL ...ESPECIALLY BY MONDAY. BOTH THE ECMWF AND GFS
SUGGEST ANOTHER WEATHER SYSTEM BRINGING MORE RAIN EARLY NEXT
WEEK...BUT DETAILS ARE VERY UNCERTAIN AT THIS TIME. -MCCOY
&&
.AVIATION...MIXED FLIGHT CONDITIONS WITH BREEZY SW WINDS THROUGH
LATE THIS EVENING BEHIND A WARM FRONT PUSHING FURTHER INLAND.
EXPECT MOSTLY MVFR/IFR CONDITIONS ALONG THE COAST WITH STRONGER
WIND GUSTS UP TO 40-45 KT. EXPECT MOSTLY VFR/MVFR CONDITIONS
INLAND WITH GUSTS 25-30 KT. RAIN TAPERS OFF TONIGHT AND EARLY
TUESDAY AM...WITH OVERALL CONDITIONS IMPROVING TO MOSTLY VFR. THEN A
STRONG TRAILING COLD FRONT MOVES THROUGH LATER TUE AFTERNOON AND
EVENING. HEAVY RAIN...DECREASING CIGS AND VSBYS...AND VERY GUSTY
SW WINDS TO ACCOMPANY THE COLD FRONT.
KPDX AND APPROACHES...MOSTLY MVFR CIGS AROUND 1500-3500 FT IN RAIN
AND BREEZY SW WINDS WITH GUSTS 25-30 KT THROUGH 23Z TUE-02Z WED
THIS AFTERNOON AS A WARM FRONT LIFTS NORTH. VFR CONDITIONS RETURN
TONIGHT THEN NEXT STRONG COLD FRONT ARRIVES TUE AFTERNOON AND
EVENING...BRINGING HEAVIER RAIN...GUSTY S WINDS AND MVFR
CONDITIONS. FRONT IS EXPECTED TO MOVE THROUGH THE TERMINAL BY
AROUND 03Z WED...WITH WINDS SWITCHING TO W-NW BEHIND THE FRONT.
/27
&&
.MARINE...SOUTH TO SOUTHWEST WINDS STARTING TO INCREASE THIS
MORNING WITH GUSTS AROUND 33-35 KT. GALE FORCE WIND GUSTS WILL
START POPPING UP THE NEXT HOUR OVER THE NORTHERN WATERS...SO GALE
WARNING REMAINS IN EFFECT. MODELS STILL SHOWING GALES THEN MOVING
INTO THE CENTRAL WATERS LATER THIS MORNING...WITH THE STRONGEST
WIND GUSTS 40-45 KT EXPECTED THIS AFTERNOON. COULD SEE A FEW
LOCAL GUSTS NEAR 50 KT POSSIBLE BETWEEN 1-5 PM. SOUTHERLY WINDS
WILL TURN SOUTHWESTERLY AGAIN LATE THIS AFTERNOON AND THEN A RAPID
SHIFT TO NORTHWESTERLY BEHIND THE FRONT EARLY TONIGHT.
SEAS RUNNING BETWEEN 14 TO 18 FT THIS MORNING...AND EXPECT SEAS
TO PEAK AROUND 23 FT THIS AFTERNOON AND EVENING. HIGH SURF
CONDITIONS TO AFFECT TO THE SW WASHINGTON AND NW OREGON COAST
THROUGH TONIGHT.
ANOTHER FRONTAL SYSTEM IS EXPECTED FOR WED NIGHT INTO THURSDAY AND
LOOKS TO HAVE A SURFACE LOW HEADED STRAIGHT FOR NW OREGON...WHICH
WOULD BRING YET ANOTHER ROUND OF GUSTY WINDS TO THE
WATERS...PARTICULARLY OVER THE CENTRAL OREGON WATERS. MODELS THEN
AGREE ON HIGHER PRESSURE BUILDING OVER THE NE PAC FOR THE END OF
THE WEEK AND THE WEEKEND. CULLEN/27
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 7 PM PST THIS EVENING FOR COAST RANGE OF
NORTHWEST OREGON-NORTH OREGON COAST.
HIGH SURF ADVISORY FROM NOON TODAY TO MIDNIGHT PST TONIGHT FOR
NORTH OREGON COAST.
FLOOD WATCH FROM 3 PM PST THIS AFTERNOON THROUGH WEDNESDAY
AFTERNOON FOR COAST RANGE OF NORTHWEST OREGON-NORTH OREGON
COAST.
WA...HIGH WIND WARNING UNTIL 7 PM PST THIS EVENING FOR SOUTH
WASHINGTON COAST-WILLAPA HILLS.
HIGH SURF ADVISORY FROM NOON TODAY TO MIDNIGHT PST TONIGHT FOR
SOUTH WASHINGTON COAST.
PZ...GALE WARNING UNTIL 9 PM PST THIS EVENING FOR COASTAL WATERS
FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60 NM.
GALE WARNING UNTIL 9 PM PST THIS EVENING FOR COASTAL WATERS
FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 AM
PST WEDNESDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
910 PM PST MON NOV 16 2015
.SYNOPSIS...A SERIES OF MOIST FRONTAL SYSTEMS WILL BRING PERIODS OF
HEAVY RAIN...MOUNTAIN SNOW AND GUSTY WINDS TO SOUTHWEST WASHINGTON
AND NORTHWEST OREGON FOR THE NEXT COUPLE OF DAYS. THE SNOW LEVELS
WILL RISE WELL ABOVE THE CASCADES PASSES BY LATE TONIGHT. A COLDER
PATTERN MAY DEVELOP LATE THIS WEEKEND AND EARLY NEXT WEEK.
&&
.SHORT TERM..NOT A LOT OF CHANGE IN THE OVERALL PATTERN OR FORECASTS.
WARM FRONT IS NOW PUSHING ONSHORE...AS EVIDENT BY GUSTY SOUTH WINDS
AND TEMPERATURES RISING INTO THE MID AND UPPER 50S THIS EVENING ON
THE COAST. AT 8 PM...ASTORIA WAS AT 58 DEG.
SNOW LEVEL THIS EVENING STILL HOLDING BETWEEN 3500 AND 4000
FEET...HIGHEST OVER LANE COUNTY. BUT...WITH WARM FRONT PUSHING
ONSHORE...SNOW LEVELS ARE RISING. NOAA PROFILERS INDICATED SNOW LEVEL
NOW NEAR 7000 FEET OVER THE COAST RANGE AND WILLAMETTE VALLEY. THAT
IS A JUMP OF 3000 TO 3500 FEET SINCE 5 PM. SO...WITH SNOW LEVELS
RISING RAPIDLY...ANY ACCUMULATING SNOW WILL BE PUSHED HIGHER ABOVE
PASSES OVER NEXT SEVERAL HOURS...AND RELEGATED TO ONLY THE HIGHER
PEAKS ABOVE 7000 FEET AFTER MIDNIGHT. WILL LET CURRENT WINTER WEATHER
ADVISORY FOR S WASHINGTON CASCADES EXPIRE THIS EVENING.
GUSTY SOUTH WINDS WILL CONTINUE AS THE WARM FRONT MOVES INLAND. GUSTS
ALONG THE COAST AND COAST RANGE AROUND 45 TO 55 MPH...BUT WOULD NOT
RULE OUT A FEW GUSTS CLOSER TO 60 MPH UNTIL 2 AM. THESE SHOULD NOT BE
WIDESPREAD OR FREQUENT ENOUGH TO WARRANT A HEADLINE. FURTHER
INLAND...SOUTH WINDS WILL GUST 30 TO 40 MPH AT TIMES UNTIL SOME TIME
AFTER MIDNIGHT...THEN EASE BACK A TAD.
THE WARM FRONT WILL PRODUCE RAINFALL TOTALS BETWEEN 1 AND 2.5 INCHES
FOR THE SW WASHINGTON COAST...WILLAPA HILLS...AND S WA CASCADES AND
FOOTHILLS THROUGH TUESDAY MORNING. THE OREGON COAST AND COAST RANGE
CAN EXPECT 0.75 TO 1.5 INCHES OF RAIN...AND THE WILLAMETTE VALLEY CAN
SEE 0.25 TO 0.75 INCH WITH THE HIGHEST TOTALS TO THE NORTH. THE RAIN
WILL BE HEAVY AT TIMES AND RESULT IN PONDING ON THE ROADS. LUCKILY
THE RIVERS HAVE BEEN LOWERING DURING THE CURRENT BREAK...AND DO NOT
EXPECT ANY RIVER FLOODING. CAN NOT TOTALLY RULE OUT FLOODING FOR THE
QUICK RESPONDING GRAYS RIVER NEAR ROSBURG. LATEST GUIDANCE SUGGESTS
THE GRAYS WILL CREST VERY CLOSE TO FLOOD STAGE. THE FLOOD THREAT FOR
SW WASHINGTON APPEARS TO BE RATHER LOCALIZED. THUS...WILL NOT ISSUE A
FLOOD WATCH AT THIS TIME.
AS THE WARM FRONT LIFTS NORTH LATE TONIGHT INTO TUESDAY MORNING...
REDUCING THE RAIN RATES. THE BAROCLINIC BOUNDARY WILL THEN SAG SOUTH
AS A COLD FRONT FOR ANOTHER ROUND OF HEAVY RAIN EARLY TUESDAY EVENING
THROUGH WEDNESDAY MORNING. THE SURFACE PRESSURE GRADIENT WILL TIGHTEN
QUITE A BIT TUESDAY THROUGH EARLY TUE EVENING. NAM SHOWS A CORE OF
55-60 KT 925 MB WIND SPEEDS OVER THE COASTAL AREAS OF SW WA AND THE N
OREGON COAST. STRONGEST SPEEDS LOOK TO OCCUR IN THE MID TO LATE
AFTERNOON THROUGH EARLY EVENING HOURS. HAVE UPGRADED TO A HIGH WIND
WARNING FOR THE S WA AND N OREGON COAST...THE WILLAPA HILLS AND N
OREGON COAST RANGE. DROPPED THE WATCH FOR THE CENTRAL OREGON COAST
AND COAST RANGE AND THE CASCADES. NAM AND GFS SOUNDINGS INDICATE
50-60 KT WIND SPEEDS AROUND 5-6K FT TUE AFTERNOON. HOWEVER...EXPECT
WARNING LEVEL GUSTS...IN EXCESS OF 75 MPH...TO BE CONFINED TO THE
HIGHER AND EXPOSED PORTIONS OF THE CASCADES. THE MAJOR CASCADE
ROADWAYS...COMMUNITIES AND SKI AREAS ARE SHELTERED TO SOME DEGREE
THUS IT WILL BE DIFFICULT TO REALIZE WARNING-LEVEL WIND SPEEDS IN
THOSE LOCATIONS.
THE COLD FRONT WILL MOVE RATHER QUICKLY...BUT HIGH MOISTURE VALUES
WILL STILL PRODUCE DECENT RAIN...ESPECIALLY OVER THE HIGHER TERRAIN
WHERE THE SW TO W WIND WILL CONTRIBUTE TO OROGRAPHIC ENHANCEMENT. 12Z
MODELS SUGGEST ANOTHER PEAK PERIOD OF PRECIP TO OCCUR BETWEEN 00Z AND
06Z WED. GFS AND NAM ARE A LITTLE SLOWER SAGGING THE FRONTAL BOUNDARY
SOUTH COMPARED TO THE ECMWF. SNOW LEVELS WILL STAY ABOVE 6000 FEET
THROUGH ABOUT 06Z WED THEN DROP BELOW THE PASSES OVERNIGHT AND INTO
WED MORNING. THE PRECIPITATION WILL BE WANING AS SNOW LEVELS
FALL...SO DO NOT EXPECT SIGNIFICANT SNOW ACCUMULATIONS.
ANOTHER MOIST WARM FRONT WILL APPROACH LATE WEDNESDAY...BUT MODELS
DIFFER ON THE TIMING AND DETAILS. THIS WARM-FRONTAL SYSTEM DOES NOT
APPEAR TO BE AS MOIST OR PROLONGED AS THE PREVIOUS ONES. LATEST GFS
SHOWS THE HEAVIEST PRECIP OVER NW OREGON WED NIGHT...INSTEAD OF SW
WASHINGTON. THE ECMWF IS A FEW HOURS SLOWER BUT HAS THE PRECIP CORE
STRADDLING THE COLUMBIA RIVER. HOWEVER...MODELS DO AGREE THAT THIS
BARCLINIC BOUNDARY WEAKENS SOMEWHERE OVER CENTRAL AND SOUTHERN OREGON
THU. WEISHAAR/ROCKEY.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...A SHORTWAVE MOVES
QUICKLY ACROSS THE AREA FRIDAY BRINGING ANOTHER CHANCE FOR
RAIN...THOUGH LIKELY NOT VERY MUCH. SNOW LEVELS WILL BE DOWN AROUND
4000 TO 6000 FT...SO THE PASSES MAY SEE ANOTHER INCH OR TWO OF SNOW.
BEYOND FRIDAY...THE GFS BUILDS HIGH PRESSURE OVER THE AREA KEEPING
US DRY THROUGH THE WEEKEND...WHILE THE ECMWF IS A LITTLE SLOWER
MOVING THE SHOWERS OUT OF OUR AREA AND KEEPS A CHANCE OF RAIN
THROUGH SATURDAY. BY SUNDAY AT THE LATEST...WE SHOULD BE DRY WITH
HIGH PRESSURE OVER THE AREA. TEMPERATURES WILL COOL DOWN AS WELL
...ESPECIALLY BY MONDAY. BOTH THE ECMWF AND GFS SUGGEST ANOTHER
WEATHER SYSTEM BRINGING MORE RAIN EARLY NEXT WEEK...BUT DETAILS ARE
VERY UNCERTAIN AT THIS TIME. -MCCOY
&&
.AVIATION...A WARM FRONT MOVING ONSHORE HAS BROUGHT INCREASING
RAIN AND STEADILY LOWERING CIGS THIS EVENING. CONDITIONS OVER THE
INTERIOR LOWLANDS ARE MOSTLY MVFR AT THIS TIME...WHILE THE COAST
IS SEEING A MIX OF MVFR AND IFR. EXPECT LITTLE CHANGE THROUGH THE
REST OF THE EVENING. THE FRONT WILL SLOWLY PUSH NORTH
OVERNIGHT...WHICH WILL ALLOW RAIN TO TAPER OFF FOR AREAS SOUTH OF
THE PDX METRO AREA...AND MAY ALLOW FOR SOME IMPROVEMENT FROM SOUTH
TO NORTH TUE AM. A STRONG TRAILING COLD FRONT MOVES THROUGH LATER
TUE AFTERNOON AND EVENING. HEAVY RAIN...DECREASING CIGS AND
VSBYS...AND VERY GUSTY SW WINDS TO ACCOMPANY THE COLD FRONT. THE
COASTAL SITES MAY SEE WINDS GUSTING 40 TO 45 KT AHEAD OF THE
FRONTAL PASSAGE.
KPDX AND APPROACHES...EXPECT MVFR CIGS IN RAIN TO CONTINUE TUE AM
AS A WARM FRONT LIFTS NORTH. THE FRONT WILL MOVE SOUTH AS A STRONG
COLD FRONT TUE AFTERNOON AND EVENING. EXPECT HEAVIER RAIN AND
GUSTY SOUTHERLY WINDS TO DEVELOP AHEAD OF THE FRONT AFTER 21Z TUE.
THE FRONT IS EXPECTED TO MOVE THROUGH THE TERMINAL BY AROUND 03Z
WED...WITH WINDS SWITCHING TO W-NW BEHIND THE FRONT. PYLE
&&
.MARINE...A ROUND OF STRONG SOUTHERLY GALE FORCE WINDS AFFECTED
THE WATERS EARLIER THIS AFTERNOON AND EARLY EVENING IN ASSOCIATION
WITH A WARM FRONT. WINDS HAVE TURNED MORE SOUTHWESTERLY AND
DROPPED OFF OVER THE PAST FEW HOURS AS THE FRONT HAS MOVED
ONSHORE...AND ARE NOW GUSTING AROUND 25 TO 30 KT. THE LATEST SHORT
TERM MODELS INCLUDING THE RUC AND HRRR INDICATING GUSTS OF 30 TO
35 KT WILL CONTINUE OVER THE NORTHERN OUTER WATERS OVERNIGHT...SO
DECIDED TO ISSUE A NEW GALE WARNING FOR ZONE 270 STARTING
IMMEDIATELY AND CONTINUING THROUGH TUE EVENING.
OTHERWISE...EXPECT A RELATIVE LULL IN THE WINDS WILL SMALL CRAFT
ADVISORY WINDS SPEEDS OVERNIGHT. SEAS WILL REMAIN IN THE 13 TO 16 FT
THROUGH EARLY AM TUE.
A STRONG TRAILING COLD FRONT WILL MOVE THROUGH THE WATERS TUE AND
TUE EVENING. SOUTHERLY WINDS WILL PICK UP AGAIN AHEAD OF THE
FRONT...WITH GUSTS 35 TO 45 KT EXPECTED TO DEVELOP IN THE MORNING
FOR THE NORTHERN WATERS AND IN THE AFTERNOON AND EVENING FURTHER
SOUTH AS THE FRONT MOVES THROUGH THE WATERS FROM THE NORTH. A GALE
WARNING IS IN EFFECT FOR ALL OF THE WATERS DURING THIS TIME. IT IS
NOT OUT OF THE QUESTION THAT A FEW LOW END STORM FORCE GUSTS WILL
OCCUR OVER THE NORTHERN WATERS. SOUTHERLY WINDS WILL TURN
SOUTHWESTERLY AGAIN LATE TUESDAY AND THEN A RAPID SHIFT TO
NORTHWESTERLY BEHIND THE FRONT TUESDAY EVENING.
ENHANCED WESTERLY SWELL ASSOCIATED WITH THIS SYSTEM APPROACHING
WILL BUILD IN DURING THE DAY TUE...WITH SEAS EXPECTED TO REACH 20
TO 23 FT DURING THE AFTERNOON AND EVENING. HIGH SURF CONDITIONS TO
AFFECT TO THE SW WASHINGTON AND NW OREGON COAST.
ANOTHER FRONTAL SYSTEM IS EXPECTED FOR WED NIGHT INTO THURSDAY AND
LOOKS TO HAVE A SURFACE LOW HEADED STRAIGHT FOR NW OREGON...WHICH
WOULD BRING YET ANOTHER ROUND OF GUSTY WINDS TO THE WATERS.
MODELS THEN AGREE ON HIGHER PRESSURE BUILDING OVER THE NE PAC FOR
THE END OF THE WEEK AND THE WEEKEND. PYLE
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING FROM 10 AM TO 7 PM TUESDAY FOR COAST
RANGE OF NORTHWEST OREGON-NORTH OREGON COAST.
HIGH SURF ADVISORY FROM TUE AFTERNOON AND TUE EVENING ON
THE NORTH OREGON COAST.
WA...HIGH WIND WARNING FROM 10 AM TO 7 PM PST TUESDAY FOR SOUTH
WASHINGTON COAST-WILLAPA HILLS.
HIGH SURF ADVISORY FROM NOON TUESDAY TO MIDNIGHT PST TUESDAY
NIGHT FOR SOUTH WASHINGTON COAST.
WINTER WEATHER ADVISORY UNTIL 10 PM PST THIS EVENING FOR SOUTH
WASHINGTON CASCADES.
PZ...HIGH WIND WARNING FROM 10 AM TO 7 PM PST TUESDAY.
GALE WARNING UNTIL 9 PM PST TUESDAY FOR WATERS FROM CAPE
SHOALWATER TO CASCADE HEAD FROM 10 TO 60 NM OFFSHORE.
GALE WARNING FROM 11 AM TO 9 PM PST TUESDAY FOR COASTAL WATERS
FROM CASCADE HEAD TO FLORENCE.
GALE WARNING FROM 7 AM TO 9 PM PST TUESDAY FOR COASTAL WATERS
FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 10 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10 PM
PST TUESDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
940 PM EST WED NOV 18 2015
.SYNOPSIS...
WIDESPREAD RAINFALL IS EXPECTED TONIGHT AND TOMORROW MORNING AHEAD
OF A COLD FRONT. AFTER THE FRONTAL PASSAGE TOMORROW MORNING...COOL
AND DRY HIGH PRESSURE WILL MOVE BACK OVER THE REGION AND REMAIN IN
PLACE THROUGH SATURDAY. ANOTHER COLD FRONT WILL CROSS THE AREA ON
SUNDAY...WITH EVEN COLDER HIGH PRESSURE SPREADING OVER THE REGION IN
ITS WAKE.
&&
.NEAR TERM /THROUGH THURSDAY/...
915 PM UPDATE...PREFRONTAL BAND OF RAIN NOW COVERS MOST OF THE CWFA
WEST OF I-77. EMBEDDED WITHIN ARE A FEW LINEARLY ORIENTED CONVECTIVE
BANDS THOUGH NOT EVEN LIGHTNING HAS BEEN DETECTED IN OUR AREA OVER
THE PAST HOUR OR SO. INSTABILITY IS PROVING HARD TO COME BY SO
FAR. RAP HAS BACKED OFF/DELAYED EARLIER PROGS OF INCREASING SBCAPE
OVER OUR LOWER PIEDMONT AREAS...NOW SUGGESTING THEY WON/T SEE MUCH
FORM UNTIL WELL AFTER MIDNIGHT. BACK EDGE OF THE PRECIP SHIELD
LOOKS LIKELY TO WORK INTO OUR WRNMOST ZONES IN THE NEXT COUPLE
HOURS. A PENCIL-THIN BAND OF ACTIVITY IS ORIENTED RIGHT ALONG
THE SFC FRONT OVER THE CUMBERLAND PLATEAU...AND DESPITE STRONG
UPPER FORCING THIS DOES NOT STAND MUCH CHANCE OF STRENGTHENING
AS IT ENCOUNTERS THE MTNS. PRESENT PLANS ARE TO KEEP THE TORNADO
WATCH IN EFFECT UNTIL 300 A.M. BUT THE WINDOW OF OPPORTUNITY IS
CURRENTLY SHRINKING...IT WOULD APPEAR.
AS FAR AS HYDRO...MOST SITES AWAY FROM UPSLOPE AREAS ARE REPORTING
RATES OF 0.15 TO 0.5 INCHES PER HOUR IN GENERAL...WITH SIGNIFICANT
ENHANCEMENT COMING AS CONVECTIVE FEATURES PASS THROUGH. RATES/ACCUMS
REPORTED BY MESONET GAGES ALONG THE ESCARPMENT OF COURSE ARE
SUBSTANTIALLY HIGHER. I REVISED QPF AND THE STORM TOTAL PRODUCT WITH
EXTRA WEIGHT ON THE HIGH-RES GUIDANCE WHICH AS A WHOLE REFLECTS A
SIMILAR DISTRIBUTION OF PRECIP. WE ARE SEEING SOME LOCALIZED FLOOD
ISSUES IN THE USUAL AREAS IN THE FOOTHILLS. THE LATER POSSIBILITY
OF CONVECTION HOWEVER DOES STILL IMPLY SOME LONGER-DURATION TYPE
ISSUES MAY RESULT OVER PARTS OF THE UPSTATE.
AS OF 235 PM...MID AFTERNOON KGSP WSR-88D VWP INDICATES 3-6 KFT
WINDS WERE FROM THE SE BETWEEN 40-45 KTS. NEAR TERM MODELS INDICATE
THAT MOISTURE SOURCED FROM THE GULF OF MEXICO AND THE WESTERN
ATLANTIC WILL LIFT ACROSS NE GA AND THE WESTERN CAROLINAS...PW
VALUES WILL RISE TO NEAR 2 INCHES BY 23Z. THE COMBINATION OF
STRONG UPSLOPE FLOW AND DEEP MOISTURE WILL SUPPORT A SOLID 4 TO
6 HOURS OF ADDITIONAL UPSLOPE MODERATE RAINFALL ALONG THE EAST
FACING SLOPES BEFORE THE PRE FRONTAL CONVECTIVE BAND ARRIVES. AS
OF 230 PM...OBSERVED RAINFALL TOTALS RANGED FROM 3.2 INCHES NEAR
LAKE TOXAWAY TO 1 TO 1.5 INCHES ACROSS THE SALUDA GRADE.
THIS EVENING...12Z GFS INDICATES A LARGE FIELD OF Q-VECTOR
CONVERGENCE WILL SPREAD ACROSS THE FORECAST AREA LATE THIS AFTERNOON
AND EVENING. AT H3...THE RIGHT ENTRANCE REGION OF A SOUTH-NORTH
160KT JET WILL SLIDE OVER THE CWA...EXITING AFTER 3Z.
CAMS INDICATE THAT A WIDE BAND PRE FRONTAL BAND OF CONVECTION WILL
SLIDE EAST ACROSS EASTERN TN/NRN GA BETWEEN 23Z TO 1Z. NAM FORECAST
SOUNDINGS ALONG AND AHEAD OF THE CONVECTIVE BAND INDICATES 0-1
KM SHEAR OVER 400 M2/S2...AND 300-500 J/KG OF SB CAPE...AND 0-1
KM EHI AS HIGH AS 1.25 M2/S2 ACROSS THE LAKELANDS. INSTABILITY
PARAMETERS RISE AFTER 0Z THURS. IN ADDITION TO MODERATE TO HEAVY
RAIN SHOWERS...I WILL INCREASE THE MENTION OF TSRA ACROSS THE
UPPER SAVANNAH RIVER VALLEY ACROSS THE PIEDMONT. IN AGREEMENT WITH
UPDATED DY1 CONVECTIVE OUTLOOK...I WILL ADD A MENTION OF SVR TSRA
ACROSS THE UPPER SAVANNAH RIVER VALLEY IN THE HWO.
SIGNIFICANT SYNOPTIC SCALE DYNAMICS...STRONG UPSLOPE FLOW...AND
A PASSING WINDOW FOR DEEP CONVECTION SHOULD RESULT IN HEAVY
RAINFALL RATES THIS EVENING AND INTO EARLY THURSDAY MORNING. IT
IS POSSIBLE THAT RAINFALL RATES COULD EXCEED THE 1-3 HR FFG ACROSS
THE MTNS...FOOTHILLS...THE WESTERN UPSTATE...AND EXTREME NE GA. IN
ADDITION...A COUPLE OF OPERATIONAL FORECASTS ALONG MAIN STEM RIVERS
INDICATE STAGES ABOVE FLOOD STAGE. I WILL CONTINUE TO HIGHLIGHT
THE RAINFALL THREAT WITH A FLASH FLOOD WATCH INTO THURSDAY MORNING.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 215 PM EST...BRIEF AND SHALLOW NW FLOW MOISTURE WILL QUICKLY
DISSIPATE ACROSS THE NORTHERN MOUNTAINS THURSDAY EVENING.
OTHERWISE...AN UPPER CYCLONE OVER THE WESTERN GREAT LAKES WILL LIFT
NORTHEAST INTO CANADA THURSDAY NIGHT THROUGH FRIDAY LEAVING
RELATIVELY ZONAL FLOW IN PLACE OVER THE SOUTHEAST. UNDER THE ZONAL
FLOW...SPRAWLING SURFACE HIGH PRESSURE WILL BUILD EASTWARD FROM THE
MID MS RIVER VALLEY TO THE APPALACHIANS THROUGH LATE WEEK. TEMPS
CLOSE TO CLIMO FRI WILL FALL BELOW CLIMO SATURDAY WITH NE WINDS
AROUND THE SFC HIGH. MEANWHILE...A TROUGH WILL DIG FROM THE NORTHERN
PLAINS INTO THE MIDWEST FRIDAY NIGHT THROUGH SATURDAY. THIS SYSTEM
WILL PUSH A REINFORCING COLD FRONT AND A NARROW BAND OF MOISTURE TO
THE SPINE OF THE SOUTHERN APPALACHIANS BY LATE DAY ON SATURDAY. VERY
LITTLE MOISTURE RECOVERY IS EXPECTED AHEAD OF THE FRONTAL
SYSTEM...WITH JUST LATE DAY SLIGHT CHANCES OF SHOWERS IN THE WESTERN
MOUNTAINS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 215 PM WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
SUNDAY WITH STEEP UPPER TROFFING CENTERED OVER THE GREAT LAKES AND
UPPER RIDGING OVER THE WESTERN CONUS. THE MODELS DIFFER WRT THE
PROGRESSION OF THE TROF OVER THE NEXT 24 TO 48 HRS. THE LATEST 12Z
GFS AMPLIFIES THE SYSTEM AND MOVES THE TROF AXIS RIGHT OVER THE CWFA
LATE SUN/EARLY MON AND THEN QUICKLY MOVES THE SYSTEM OFFSHORE. THE
PATTERN FLATTENS OUT IN THE TROFS WAKE WITH HEIGHTS SLOWLY RISING
FOR THE REMAINDER OF THE PERIOD. THE ECMWF...ON THE OTHER
HAND...LIFTS THE TROF NE OF THE REGION ON SUN WHILE SIMULTANEOUSLY
DEVELOPING A POTENT SHORTWAVE ON THE BACKSIDE OF THE MAIN TROF. THIS
SHORTWAVE QUICKLY APPROACHES THE FCST AREA FROM THE WEST EARLY MON
AND MOVES OVERHEAD LATER THAT DAY. THE REMAINDER OF THE FCST IS
SIMILAR TO THE GFS WITH HEIGHTS RISING AS UPPER RIDGING MOVES BACK
OVER THE REGION THRU MIDWEEK.
AT THE SFC...A DRY COLD FRONT WILL BE MOVING INTO THE FCST AREA BY
THE START OF THE PERIOD AS ITS PARENT LOW PASSES OVER THE EASTERN
GREAT LAKES. THE FRONT IS EXPECTED TO MOVE THRU THE AREA QUICKLY
WITH COLD AND DRY HIGH PRESSURE OVERSPREADING THE REGION AGAIN IN
ITS WAKE. THE GFS HAS THE HIGH LINGERING OVER THE REGION THRU DAY 7
WITH IT SHIFTING NE TOWARDS NEW ENGLAND...HOWEVER THE ECMWF TRIES TO
SPIN UP A LOW OFF THE EAST COAST OF FLORIDA EARLY MON AND MOVE THE
SYSTEM NE OVER THE NEXT COUPLE OF DAYS. AT THE PRESENT TIME...IT
REMAINS FAR ENOUGH OFFSHORE THAT IT DOES NOT DIRECTLY IMPACT OUR
SENSIBLE WX. AS FOR THE SENSIBLE FCST...I ONLY KEEP A SLIGHT CHANCE
POP ALONG THE NC/TENN BORDER FOR EARLY SUN MORNING AS THE FRONT
MOVES THRU WITH DRY CONDITIONS AFTER THAT. THE TEMPS/THICKNESSES LOOK
COLD ENOUGH TO SUPPORT LIGHT SNOW SHOWERS IF PRECIP DOES
DEVELOP...BUT IT WOULD NOT AMOUNT TO MUCH. SIGNIFICANT CAA WILL KEEP
TEMPS WELL BELOW NORMAL THRU THE PERIOD WITH SOME WARMING ON TUES
AND WED AS THICKNESSES RECOVER.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
AT KCLT...SHOWERS WILL OCCUR AT TIMES THIS EVENING AND EARLY THU
MRNG. MAIN IMPACTS FROM THESE SHOWERS ARE EXPECTED TO BE PATCHY MVFR
CIGS AND PERHAPS OCNL VISIBILITY RESTRICTIONS. A BAND OF HEAVY RAIN
AND PERHAPS EMBEDDED TS WILL PRECEDE A COLD FRONT ACRS THE FIELD
CLOSER TO DAWN. MOST MODELS HAVE TRENDED A LITTLE LATER WITH THE
FRONT...AND TIMING NOW SUGGESTS IMPACTS DURING EARLY MORNING OPS AT
THE FIELD. WEAK COLD AIR DAMMING HANGS ON BY A THREAD. A STRONG LOW
LEVEL JET PRECEDING THE FRONT AND JUST ATOP THE WEDGE BOUNDARY IS
LIKELY TO CAUSE SOME MARGINAL LLWS ISSUES MOST OF THE NIGHT. AS
WEDGE BOUNDARY RETREATS JUST BEFORE DAWN SHORT RANGE GUIDANCE
HINTS AT POSSIBLE SFC BASED CONVECTION...WHICH IN THE PRESENCE
OF STRONG SHEAR WILL BE CAPABLE OF ISOLD DAMAGING WINDS...IF IT
FORMS. CONDITIONS IMPROVE JUST AFTER DAYBREAK...WITH CONDITIONS
RAPIDLY RETURNING TO VFR. SFC WINDS VEER TO NW BY MID-AFTN.
ELSEWHERE...RESTRICTIONS WILL ACCOMPANY A BROAD BAND OF MODERATE
TO HEAVY RAIN ACRS THE TAF SITES TONIGHT. ANY HEAVY RAIN EASILY
WILL BE CAPABLE OF IFR VSBY. EVEN AFTER RAIN TAPERS OFF BEHIND
THE BAND SIGNIFICANT DRYING IS NOT EXPECTED TO OCCUR UNTIL AFTER
DAYBREAK...SO LOW CIGS AND FOG WILL LINGER. AN OCCASIONAL LLWS
THREAT WILL BE PRESENT OVER PARTS OF THE NC MTNS UNTIL DEPARTURE OF
LOW LEVEL JET PRECEDING INCOMING FRONT. MESOSCALE GUIDANCE AND NAM
DO INDICATE ENOUGH SFC BASED INSTABILITY DEVELOPS OVER THE UPSTATE
TO EXPECT A FEW TSRA WILL DEVELOP IN THESE AREAS...AND GIVEN THE
ROBUST WIND SHEAR BRIEF DAMAGING WIND GUSTS ARE A POSSIBILITY. VFR
EXPECTED ONCE MRNG RESTRICTIONS MIX OUT...WITH SKIES EVENTUALLY
CLEARING. WINDS WILL VEER FROM SE OVERNIGHT TO NW TOMORROW...LATE
MRNG IN THE MTNS/FOOTHILLS AND AFTN PIEDMONT.
OUTLOOK...DRY HIGH PRESSURE WILL BRING VFR CONDITIONS FOR THURSDAY
NIGHT AND FRIDAY. A SECONDARY COLD FRONT COULD BRING SOME LIGHT SNOW
AND MINOR VSBY RESTRICTIONS TO THE HIGHER NC MTNS SATURDAY NIGHT.
CONFIDENCE TABLE...
02-08Z 08-14Z 14-20Z 20-00Z
KCLT MED 72% MED 73% LOW 53% HIGH 100%
KGSP MED 77% MED 70% MED 79% HIGH 100%
KAVL MED 67% MED 70% LOW 50% HIGH 100%
KHKY MED 69% HIGH 83% LOW 53% HIGH 100%
KGMU MED 64% MED 75% HIGH 91% HIGH 100%
KAND MED 79% MED 76% HIGH 94% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR GAZ010-017-018-
026-028-029.
NC...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR NCZ033-048>053-
058-059-062>065-501>510.
SC...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR SCZ001>007-010-
011.
&&
$$
SYNOPSIS...JPT
NEAR TERM...NED/WIMBERLEY
SHORT TERM...HG
LONG TERM...JPT
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
831 PM EST WED NOV 18 2015
.SYNOPSIS...
WIDESPREAD RAINFALL IS EXPECTED TONIGHT AND TOMORROW MORNING AHEAD
OF A COLD FRONT. AFTER THE FRONTAL PASSAGE TOMORROW MORNING...COOL
AND DRY HIGH PRESSURE WILL MOVE BACK OVER THE REGION AND REMAIN IN
PLACE THROUGH SATURDAY. ANOTHER COLD FRONT WILL CROSS THE AREA ON
SUNDAY...WITH EVEN COLDER HIGH PRESSURE SPREADING OVER THE REGION IN
ITS WAKE.
&&
.NEAR TERM /THROUGH THURSDAY/...
830 PM UPDATE...TORNADO WATCH NOW IN EFFECT FOR A PORTION OF THE
SRN UPSTATE AND HART/ELBERT COUNTIES IN GA. TORNADO THREAT IS STILL
TIED TO DEVELOPMENT OF SFC BUOYANCY IN THE COMING HOURS...AS SEEN
ON RECENT RAP PLOTS. ISOLATED SEVERE AND DAMAGING WIND WORDING
HAVE BEEN ADDED TO THE FCST IN THE WATCH AREA.
630 PM UPDATE...NARROW BUT LOCALLY INTENSE BAND OF LOW TOPPED
CONVECTION HAS MOVED THRU THE ATLANTA METRO AND IS PROCEEDING EAST
TOWARD SC. THE NORTH END OF THIS LINE WILL PUSH ACROSS OUR SRN GA/SC
ZONES OVER THE NEXT 3 HRS OR SO...WITH ONLY SLIGHT INSTABILITY
TO SUSTAIN IT. WE ARE STILL MONITORING THE LINE FOR ANY FEATURES
SUGGESTIVE OF DAMAGING WINDS BUT THE MORE SIGNIFICANT THREAT DOES
LOOK TO BE TO OUR SOUTH WHERE SBCAPE IS STILL APPRECIABLE. HOWEVER
MESO MODELS DO SUGGEST LINEARLY ORGANIZED CONVECTION IS STILL
POSSIBLE OVERNIGHT AS VERY LOW LEVEL WARM ADVECTION AND RETREAT
OF WEDGE BOUNDARY OCCUR CLOSER TO THE FROPA. HRRR RESOLVES A FEW
STRONG UPDRAFTS MOVING ACRS THE I-85 CORRIDOR AFTER MIDNIGHT THOUGH
COVERAGE DIMINISHES WITH TIME.
18Z NAM/GFS AND RECENT HRRR RUNS TRENDED TOWARD A SLOWER FROPA IN
GENERAL...REFLECTING LESS OF A CONVECTIVE HEAVY RAIN THREAT THIS
EVENING BUT PERHAPS MORE OF A DURATION FLOOD THREAT IN THE EARLY
MORNING. NONETHELESS THE MOST SIGNIFICANT RAINFALL IS EXPECTED
TO HAVE DEPARTED THE AREA BY 12Z. POPS/SKY/WINDS/TEMPS HAVE BEEN
UPDATED THRU TOMORROW. THE WIND EVENT IN THE MTNS HAS PEAKED WITH
RIDGETOP OBS NOT WARRANTING AN ADVISORY...SO THE WIND ADVISORY
FOR HIGH ELEVS OF THE MTN ZONES HAS BEEN ALLOWED TO EXPIRE. FLASH
FLOOD WATCH STILL LOOKS GOOD.
AS OF 235 PM...MID AFTERNOON KGSP WSR-88D VWP INDICATES 3-6 KFT
WINDS WERE FROM THE SE BETWEEN 40-45 KTS. NEAR TERM MODELS INDICATE
THAT MOISTURE SOURCED FROM THE GULF OF MEXICO AND THE WESTERN
ATLANTIC WILL LIFT ACROSS NE GA AND THE WESTERN CAROLINAS...PW
VALUES WILL RISE TO NEAR 2 INCHES BY 23Z. THE COMBINATION OF
STRONG UPSLOPE FLOW AND DEEP MOISTURE WILL SUPPORT A SOLID 4 TO
6 HOURS OF ADDITIONAL UPSLOPE MODERATE RAINFALL ALONG THE EAST
FACING SLOPES BEFORE THE PRE FRONTAL CONVECTIVE BAND ARRIVES. AS
OF 230 PM...OBSERVED RAINFALL TOTALS RANGED FROM 3.2 INCHES NEAR
LAKE TOXAWAY TO 1 TO 1.5 INCHES ACROSS THE SALUDA GRADE.
THIS EVENING...12Z GFS INDICATES A LARGE FIELD OF Q-VECTOR
CONVERGENCE WILL SPREAD ACROSS THE FORECAST AREA LATE THIS AFTERNOON
AND EVENING. AT H3...THE RIGHT ENTRANCE REGION OF A SOUTH-NORTH
160KT JET WILL SLIDE OVER THE CWA...EXITING AFTER 3Z.
CAMS INDICATE THAT A WIDE BAND PRE FRONTAL BAND OF CONVECTION WILL
SLIDE EAST ACROSS EASTERN TN/NRN GA BETWEEN 23Z TO 1Z. NAM FORECAST
SOUNDINGS ALONG AND AHEAD OF THE CONVECTIVE BAND INDICATES 0-1
KM SHEAR OVER 400 M2/S2...AND 300-500 J/KG OF SB CAPE...AND 0-1
KM EHI AS HIGH AS 1.25 M2/S2 ACROSS THE LAKELANDS. INSTABILITY
PARAMETERS RISE AFTER 0Z THURS. IN ADDITION TO MODERATE TO HEAVY
RAIN SHOWERS...I WILL INCREASE THE MENTION OF TSRA ACROSS THE
UPPER SAVANNAH RIVER VALLEY ACROSS THE PIEDMONT. IN AGREEMENT WITH
UPDATED DY1 CONVECTIVE OUTLOOK...I WILL ADD A MENTION OF SVR TSRA
ACROSS THE UPPER SAVANNAH RIVER VALLEY IN THE HWO.
SIGNIFICANT SYNOPTIC SCALE DYNAMICS...STRONG UPSLOPE FLOW...AND
A PASSING WINDOW FOR DEEP CONVECTION SHOULD RESULT IN HEAVY
RAINFALL RATES THIS EVENING AND INTO EARLY THURSDAY MORNING. IT
IS POSSIBLE THAT RAINFALL RATES COULD EXCEED THE 1-3 HR FFG ACROSS
THE MTNS...FOOTHILLS...THE WESTERN UPSTATE...AND EXTREME NE GA. IN
ADDITION...A COUPLE OF OPERATIONAL FORECASTS ALONG MAIN STEM RIVERS
INDICATE STAGES ABOVE FLOOD STAGE. I WILL CONTINUE TO HIGHLIGHT
THE RAINFALL THREAT WITH A FLASH FLOOD WATCH INTO THURSDAY MORNING.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 215 PM EST...BRIEF AND SHALLOW NW FLOW MOISTURE WILL QUICKLY
DISSIPATE ACROSS THE NORTHERN MOUNTAINS THURSDAY EVENING.
OTHERWISE...AN UPPER CYCLONE OVER THE WESTERN GREAT LAKES WILL LIFT
NORTHEAST INTO CANADA THURSDAY NIGHT THROUGH FRIDAY LEAVING
RELATIVELY ZONAL FLOW IN PLACE OVER THE SOUTHEAST. UNDER THE ZONAL
FLOW...SPRAWLING SURFACE HIGH PRESSURE WILL BUILD EASTWARD FROM THE
MID MS RIVER VALLEY TO THE APPALACHIANS THROUGH LATE WEEK. TEMPS
CLOSE TO CLIMO FRI WILL FALL BELOW CLIMO SATURDAY WITH NE WINDS
AROUND THE SFC HIGH. MEANWHILE...A TROUGH WILL DIG FROM THE NORTHERN
PLAINS INTO THE MIDWEST FRIDAY NIGHT THROUGH SATURDAY. THIS SYSTEM
WILL PUSH A REINFORCING COLD FRONT AND A NARROW BAND OF MOISTURE TO
THE SPINE OF THE SOUTHERN APPALACHIANS BY LATE DAY ON SATURDAY. VERY
LITTLE MOISTURE RECOVERY IS EXPECTED AHEAD OF THE FRONTAL
SYSTEM...WITH JUST LATE DAY SLIGHT CHANCES OF SHOWERS IN THE WESTERN
MOUNTAINS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 215 PM WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
SUNDAY WITH STEEP UPPER TROFFING CENTERED OVER THE GREAT LAKES AND
UPPER RIDGING OVER THE WESTERN CONUS. THE MODELS DIFFER WRT THE
PROGRESSION OF THE TROF OVER THE NEXT 24 TO 48 HRS. THE LATEST 12Z
GFS AMPLIFIES THE SYSTEM AND MOVES THE TROF AXIS RIGHT OVER THE CWFA
LATE SUN/EARLY MON AND THEN QUICKLY MOVES THE SYSTEM OFFSHORE. THE
PATTERN FLATTENS OUT IN THE TROFS WAKE WITH HEIGHTS SLOWLY RISING
FOR THE REMAINDER OF THE PERIOD. THE ECMWF...ON THE OTHER
HAND...LIFTS THE TROF NE OF THE REGION ON SUN WHILE SIMULTANEOUSLY
DEVELOPING A POTENT SHORTWAVE ON THE BACKSIDE OF THE MAIN TROF. THIS
SHORTWAVE QUICKLY APPROACHES THE FCST AREA FROM THE WEST EARLY MON
AND MOVES OVERHEAD LATER THAT DAY. THE REMAINDER OF THE FCST IS
SIMILAR TO THE GFS WITH HEIGHTS RISING AS UPPER RIDGING MOVES BACK
OVER THE REGION THRU MIDWEEK.
AT THE SFC...A DRY COLD FRONT WILL BE MOVING INTO THE FCST AREA BY
THE START OF THE PERIOD AS ITS PARENT LOW PASSES OVER THE EASTERN
GREAT LAKES. THE FRONT IS EXPECTED TO MOVE THRU THE AREA QUICKLY
WITH COLD AND DRY HIGH PRESSURE OVERSPREADING THE REGION AGAIN IN
ITS WAKE. THE GFS HAS THE HIGH LINGERING OVER THE REGION THRU DAY 7
WITH IT SHIFTING NE TOWARDS NEW ENGLAND...HOWEVER THE ECMWF TRIES TO
SPIN UP A LOW OFF THE EAST COAST OF FLORIDA EARLY MON AND MOVE THE
SYSTEM NE OVER THE NEXT COUPLE OF DAYS. AT THE PRESENT TIME...IT
REMAINS FAR ENOUGH OFFSHORE THAT IT DOES NOT DIRECTLY IMPACT OUR
SENSIBLE WX. AS FOR THE SENSIBLE FCST...I ONLY KEEP A SLIGHT CHANCE
POP ALONG THE NC/TENN BORDER FOR EARLY SUN MORNING AS THE FRONT
MOVES THRU WITH DRY CONDITIONS AFTER THAT. THE TEMPS/THICKNESSES LOOK
COLD ENOUGH TO SUPPORT LIGHT SNOW SHOWERS IF PRECIP DOES
DEVELOP...BUT IT WOULD NOT AMOUNT TO MUCH. SIGNIFICANT CAA WILL KEEP
TEMPS WELL BELOW NORMAL THRU THE PERIOD WITH SOME WARMING ON TUES
AND WED AS THICKNESSES RECOVER.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
AT KCLT...SHOWERS WILL OCCUR AT TIMES THIS EVENING AND EARLY THU
MRNG. MAIN IMPACTS FROM THESE SHOWERS ARE EXPECTED TO BE PATCHY MVFR
CIGS AND PERHAPS OCNL VISIBILITY RESTRICTIONS. A BAND OF HEAVY RAIN
AND PERHAPS EMBEDDED TS WILL PRECEDE A COLD FRONT ACRS THE FIELD
CLOSER TO DAWN. MOST MODELS HAVE TRENDED A LITTLE LATER WITH THE
FRONT...AND TIMING NOW SUGGESTS IMPACTS DURING EARLY MORNING OPS AT
THE FIELD. WEAK COLD AIR DAMMING HANGS ON BY A THREAD. A STRONG LOW
LEVEL JET PRECEDING THE FRONT AND JUST ATOP THE WEDGE BOUNDARY IS
LIKELY TO CAUSE SOME MARGINAL LLWS ISSUES MOST OF THE NIGHT. AS
WEDGE BOUNDARY RETREATS JUST BEFORE DAWN SHORT RANGE GUIDANCE
HINTS AT POSSIBLE SFC BASED CONVECTION...WHICH IN THE PRESENCE
OF STRONG SHEAR WILL BE CAPABLE OF ISOLD DAMAGING WINDS...IF IT
FORMS. CONDITIONS IMPROVE JUST AFTER DAYBREAK...WITH CONDITIONS
RAPIDLY RETURNING TO VFR. SFC WINDS VEER TO NW BY MID-AFTN.
ELSEWHERE...RESTRICTIONS WILL ACCOMPANY A BROAD BAND OF MODERATE
TO HEAVY RAIN ACRS THE TAF SITES TONIGHT. ANY HEAVY RAIN EASILY
WILL BE CAPABLE OF IFR VSBY. EVEN AFTER RAIN TAPERS OFF BEHIND
THE BAND SIGNIFICANT DRYING IS NOT EXPECTED TO OCCUR UNTIL AFTER
DAYBREAK...SO LOW CIGS AND FOG WILL LINGER. AN OCCASIONAL LLWS
THREAT WILL BE PRESENT OVER PARTS OF THE NC MTNS UNTIL DEPARTURE OF
LOW LEVEL JET PRECEDING INCOMING FRONT. MESOSCALE GUIDANCE AND NAM
DO INDICATE ENOUGH SFC BASED INSTABILITY DEVELOPS OVER THE UPSTATE
TO EXPECT A FEW TSRA WILL DEVELOP IN THESE AREAS...AND GIVEN THE
ROBUST WIND SHEAR BRIEF DAMAGING WIND GUSTS ARE A POSSIBILITY. VFR
EXPECTED ONCE MRNG RESTRICTIONS MIX OUT...WITH SKIES EVENTUALLY
CLEARING. WINDS WILL VEER FROM SE OVERNIGHT TO NW TOMORROW...LATE
MRNG IN THE MTNS/FOOTHILLS AND AFTN PIEDMONT.
OUTLOOK...DRY HIGH PRESSURE WILL BRING VFR CONDITIONS FOR THURSDAY
NIGHT AND FRIDAY. A SECONDARY COLD FRONT COULD BRING SOME LIGHT SNOW
AND MINOR VSBY RESTRICTIONS TO THE HIGHER NC MTNS SATURDAY NIGHT.
CONFIDENCE TABLE...
01-07Z 07-13Z 13-19Z 19-00Z
KCLT MED 74% MED 73% LOW 58% HIGH 100%
KGSP MED 75% MED 66% MED 73% HIGH 100%
KAVL MED 72% MED 68% LOW 52% HIGH 100%
KHKY MED 66% MED 77% LOW 57% HIGH 100%
KGMU MED 70% MED 73% MED 79% HIGH 100%
KAND MED 79% MED 76% HIGH 90% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR GAZ010-017-018-
026-028-029.
NC...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR NCZ033-048>053-
058-059-062>065-501>510.
SC...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR SCZ001>007-010-
011.
&&
$$
SYNOPSIS...JPT
NEAR TERM...NED/WIMBERLEY
SHORT TERM...HG
LONG TERM...JPT
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
717 PM EST WED NOV 18 2015
.SYNOPSIS...
WIDESPREAD RAINFALL IS EXPECTED TONIGHT AND TOMORROW MORNING AHEAD
OF A COLD FRONT. AFTER THE FRONTAL PASSAGE TOMORROW MORNING...COOL
AND DRY HIGH PRESSURE WILL MOVE BACK OVER THE REGION AND REMAIN IN
PLACE THROUGH SATURDAY. ANOTHER COLD FRONT WILL CROSS THE AREA ON
SUNDAY...WITH EVEN COLDER HIGH PRESSURE SPREADING OVER THE REGION IN
ITS WAKE.
&&
.NEAR TERM /THROUGH THURSDAY/...
630 PM UPDATE...NARROW BUT LOCALLY INTENSE BAND OF LOW TOPPED
CONVECTION HAS MOVED THRU THE ATLANTA METRO AND IS PROCEEDING EAST
TOWARD SC. THE NORTH END OF THIS LINE WILL PUSH ACROSS OUR SRN GA/SC
ZONES OVER THE NEXT 3 HRS OR SO...WITH ONLY SLIGHT INSTABILITY
TO SUSTAIN IT. WE ARE STILL MONITORING THE LINE FOR ANY FEATURES
SUGGESTIVE OF DAMAGING WINDS BUT THE MORE SIGNIFICANT THREAT DOES
LOOK TO BE TO OUR SOUTH WHERE SBCAPE IS STILL APPRECIABLE. HOWEVER
MESO MODELS DO SUGGEST LINEARLY ORGANIZED CONVECTION IS STILL
POSSIBLE OVERNIGHT AS VERY LOW LEVEL WARM ADVECTION AND RETREAT
OF WEDGE BOUNDARY OCCUR CLOSER TO THE FROPA. HRRR RESOLVES A FEW
STRONG UPDRAFTS MOVING ACRS THE I-85 CORRIDOR AFTER MIDNIGHT THOUGH
COVERAGE DIMINISHES WITH TIME.
18Z NAM/GFS AND RECENT HRRR RUNS TRENDED TOWARD A SLOWER FROPA IN
GENERAL...REFLECTING LESS OF A CONVECTIVE HEAVY RAIN THREAT THIS
EVENING BUT PERHAPS MORE OF A DURATION FLOOD THREAT IN THE EARLY
MORNING. NONETHELESS THE MOST SIGNIFICANT RAINFALL IS EXPECTED
TO HAVE DEPARTED THE AREA BY 12Z. POPS/SKY/WINDS/TEMPS HAVE BEEN
UPDATED THRU TOMORROW. THE WIND EVENT IN THE MTNS HAS PEAKED WITH
RIDGETOP OBS NOT WARRANTING AN ADVISORY...SO THE WIND ADVISORY
FOR HIGH ELEVS OF THE MTN ZONES HAS BEEN ALLOWED TO EXPIRE. FLASH
FLOOD WATCH STILL LOOKS GOOD.
AS OF 235 PM...MID AFTERNOON KGSP WSR-88D VWP INDICATES 3-6 KFT
WINDS WERE FROM THE SE BETWEEN 40-45 KTS. NEAR TERM MODELS INDICATE
THAT MOISTURE SOURCED FROM THE GULF OF MEXICO AND THE WESTERN
ATLANTIC WILL LIFT ACROSS NE GA AND THE WESTERN CAROLINAS...PW
VALUES WILL RISE TO NEAR 2 INCHES BY 23Z. THE COMBINATION OF
STRONG UPSLOPE FLOW AND DEEP MOISTURE WILL SUPPORT A SOLID 4 TO
6 HOURS OF ADDITIONAL UPSLOPE MODERATE RAINFALL ALONG THE EAST
FACING SLOPES BEFORE THE PRE FRONTAL CONVECTIVE BAND ARRIVES. AS
OF 230 PM...OBSERVED RAINFALL TOTALS RANGED FROM 3.2 INCHES NEAR
LAKE TOXAWAY TO 1 TO 1.5 INCHES ACROSS THE SALUDA GRADE.
THIS EVENING...12Z GFS INDICATES A LARGE FIELD OF Q-VECTOR
CONVERGENCE WILL SPREAD ACROSS THE FORECAST AREA LATE THIS AFTERNOON
AND EVENING. AT H3...THE RIGHT ENTRANCE REGION OF A SOUTH-NORTH
160KT JET WILL SLIDE OVER THE CWA...EXITING AFTER 3Z.
CAMS INDICATE THAT A WIDE BAND PRE FRONTAL BAND OF CONVECTION WILL
SLIDE EAST ACROSS EASTERN TN/NRN GA BETWEEN 23Z TO 1Z. NAM FORECAST
SOUNDINGS ALONG AND AHEAD OF THE CONVECTIVE BAND INDICATES 0-1
KM SHEAR OVER 400 M2/S2...AND 300-500 J/KG OF SB CAPE...AND 0-1
KM EHI AS HIGH AS 1.25 M2/S2 ACROSS THE LAKELANDS. INSTABILITY
PARAMETERS RISE AFTER 0Z THURS. IN ADDITION TO MODERATE TO HEAVY
RAIN SHOWERS...I WILL INCREASE THE MENTION OF TSRA ACROSS THE
UPPER SAVANNAH RIVER VALLEY ACROSS THE PIEDMONT. IN AGREEMENT WITH
UPDATED DY1 CONVECTIVE OUTLOOK...I WILL ADD A MENTION OF SVR TSRA
ACROSS THE UPPER SAVANNAH RIVER VALLEY IN THE HWO.
SIGNIFICANT SYNOPTIC SCALE DYNAMICS...STRONG UPSLOPE FLOW...AND
A PASSING WINDOW FOR DEEP CONVECTION SHOULD RESULT IN HEAVY
RAINFALL RATES THIS EVENING AND INTO EARLY THURSDAY MORNING. IT
IS POSSIBLE THAT RAINFALL RATES COULD EXCEED THE 1-3 HR FFG ACROSS
THE MTNS...FOOTHILLS...THE WESTERN UPSTATE...AND EXTREME NE GA. IN
ADDITION...A COUPLE OF OPERATIONAL FORECASTS ALONG MAIN STEM RIVERS
INDICATE STAGES ABOVE FLOOD STAGE. I WILL CONTINUE TO HIGHLIGHT
THE RAINFALL THREAT WITH A FLASH FLOOD WATCH INTO THURSDAY MORNING.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 215 PM EST...BRIEF AND SHALLOW NW FLOW MOISTURE WILL QUICKLY
DISSIPATE ACROSS THE NORTHERN MOUNTAINS THURSDAY EVENING.
OTHERWISE...AN UPPER CYCLONE OVER THE WESTERN GREAT LAKES WILL LIFT
NORTHEAST INTO CANADA THURSDAY NIGHT THROUGH FRIDAY LEAVING
RELATIVELY ZONAL FLOW IN PLACE OVER THE SOUTHEAST. UNDER THE ZONAL
FLOW...SPRAWLING SURFACE HIGH PRESSURE WILL BUILD EASTWARD FROM THE
MID MS RIVER VALLEY TO THE APPALACHIANS THROUGH LATE WEEK. TEMPS
CLOSE TO CLIMO FRI WILL FALL BELOW CLIMO SATURDAY WITH NE WINDS
AROUND THE SFC HIGH. MEANWHILE...A TROUGH WILL DIG FROM THE NORTHERN
PLAINS INTO THE MIDWEST FRIDAY NIGHT THROUGH SATURDAY. THIS SYSTEM
WILL PUSH A REINFORCING COLD FRONT AND A NARROW BAND OF MOISTURE TO
THE SPINE OF THE SOUTHERN APPALACHIANS BY LATE DAY ON SATURDAY. VERY
LITTLE MOISTURE RECOVERY IS EXPECTED AHEAD OF THE FRONTAL
SYSTEM...WITH JUST LATE DAY SLIGHT CHANCES OF SHOWERS IN THE WESTERN
MOUNTAINS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 215 PM WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
SUNDAY WITH STEEP UPPER TROFFING CENTERED OVER THE GREAT LAKES AND
UPPER RIDGING OVER THE WESTERN CONUS. THE MODELS DIFFER WRT THE
PROGRESSION OF THE TROF OVER THE NEXT 24 TO 48 HRS. THE LATEST 12Z
GFS AMPLIFIES THE SYSTEM AND MOVES THE TROF AXIS RIGHT OVER THE CWFA
LATE SUN/EARLY MON AND THEN QUICKLY MOVES THE SYSTEM OFFSHORE. THE
PATTERN FLATTENS OUT IN THE TROFS WAKE WITH HEIGHTS SLOWLY RISING
FOR THE REMAINDER OF THE PERIOD. THE ECMWF...ON THE OTHER
HAND...LIFTS THE TROF NE OF THE REGION ON SUN WHILE SIMULTANEOUSLY
DEVELOPING A POTENT SHORTWAVE ON THE BACKSIDE OF THE MAIN TROF. THIS
SHORTWAVE QUICKLY APPROACHES THE FCST AREA FROM THE WEST EARLY MON
AND MOVES OVERHEAD LATER THAT DAY. THE REMAINDER OF THE FCST IS
SIMILAR TO THE GFS WITH HEIGHTS RISING AS UPPER RIDGING MOVES BACK
OVER THE REGION THRU MIDWEEK.
AT THE SFC...A DRY COLD FRONT WILL BE MOVING INTO THE FCST AREA BY
THE START OF THE PERIOD AS ITS PARENT LOW PASSES OVER THE EASTERN
GREAT LAKES. THE FRONT IS EXPECTED TO MOVE THRU THE AREA QUICKLY
WITH COLD AND DRY HIGH PRESSURE OVERSPREADING THE REGION AGAIN IN
ITS WAKE. THE GFS HAS THE HIGH LINGERING OVER THE REGION THRU DAY 7
WITH IT SHIFTING NE TOWARDS NEW ENGLAND...HOWEVER THE ECMWF TRIES TO
SPIN UP A LOW OFF THE EAST COAST OF FLORIDA EARLY MON AND MOVE THE
SYSTEM NE OVER THE NEXT COUPLE OF DAYS. AT THE PRESENT TIME...IT
REMAINS FAR ENOUGH OFFSHORE THAT IT DOES NOT DIRECTLY IMPACT OUR
SENSIBLE WX. AS FOR THE SENSIBLE FCST...I ONLY KEEP A SLIGHT CHANCE
POP ALONG THE NC/TENN BORDER FOR EARLY SUN MORNING AS THE FRONT
MOVES THRU WITH DRY CONDITIONS AFTER THAT. THE TEMPS/THICKNESSES LOOK
COLD ENOUGH TO SUPPORT LIGHT SNOW SHOWERS IF PRECIP DOES
DEVELOP...BUT IT WOULD NOT AMOUNT TO MUCH. SIGNIFICANT CAA WILL KEEP
TEMPS WELL BELOW NORMAL THRU THE PERIOD WITH SOME WARMING ON TUES
AND WED AS THICKNESSES RECOVER.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AT KCLT...SHOWERS WILL OCCUR AT TIMES THIS EVENING AND EARLY THU
MRNG. MAIN IMPACTS FROM THESE SHOWERS ARE EXPECTED TO BE PATCHY MVFR
CIGS AND PERHAPS OCNL VISIBILITY RESTRICTIONS. A BAND OF HEAVY RAIN
AND PERHAPS EMBEDDED TS WILL PRECEDE A COLD FRONT ACRS THE FIELD
CLOSER TO DAWN. MOST MODELS HAVE TRENDED A LITTLE LATER WITH THE
FRONT...AND TIMING NOW SUGGESTS IMPACTS DURING EARLY MORNING OPS AT
THE FIELD. WEAK COLD AIR DAMMING HANGS ON BY A THREAD. A STRONG LOW
LEVEL JET PRECEDING THE FRONT AND JUST ATOP THE WEDGE BOUNDARY IS
LIKELY TO CAUSE SOME MARGINAL LLWS ISSUES MOST OF THE NIGHT. AS
WEDGE BOUNDARY RETREATS JUST BEFORE DAWN SHORT RANGE GUIDANCE
HINTS AT POSSIBLE SFC BASED CONVECTION...WHICH IN THE PRESENCE
OF STRONG SHEAR WILL BE CAPABLE OF ISOLD DAMAGING WINDS...IF IT
FORMS. CONDITIONS IMPROVE JUST AFTER DAYBREAK...WITH CONDITIONS
RAPIDLY RETURNING TO VFR. SFC WINDS VEER TO NW BY MID-AFTN.
ELSEWHERE...RESTRICTIONS WILL ACCOMPANY A BROAD BAND OF MODERATE
TO HEAVY RAIN ACRS THE TAF SITES TONIGHT. ANY HEAVY RAIN EASILY
WILL BE CAPABLE OF IFR VSBY. EVEN AFTER RAIN TAPERS OFF BEHIND
THE BAND SIGNIFICANT DRYING IS NOT EXPECTED TO OCCUR UNTIL AFTER
DAYBREAK...SO LOW CIGS AND FOG WILL LINGER. AN OCCASIONAL LLWS
THREAT WILL BE PRESENT OVER PARTS OF THE NC MTNS UNTIL DEPARTURE OF
LOW LEVEL JET PRECEDING INCOMING FRONT. MESOSCALE GUIDANCE AND NAM
DO INDICATE ENOUGH SFC BASED INSTABILITY DEVELOPS OVER THE UPSTATE
TO EXPECT A FEW TSRA WILL DEVELOP IN THESE AREAS...AND GIVEN THE
ROBUST WIND SHEAR BRIEF DAMAGING WIND GUSTS ARE A POSSIBILITY. VFR
EXPECTED ONCE MRNG RESTRICTIONS MIX OUT...WITH SKIES EVENTUALLY
CLEARING. WINDS WILL VEER FROM SE OVERNIGHT TO NW TOMORROW...LATE
MRNG IN THE MTNS/FOOTHILLS AND AFTN PIEDMONT.
OUTLOOK...DRY HIGH PRESSURE WILL BRING VFR CONDITIONS FOR THURSDAY
NIGHT AND FRIDAY. A SECONDARY COLD FRONT COULD BRING SOME LIGHT SNOW
AND MINOR VSBY RESTRICTIONS TO THE HIGHER NC MTNS SATURDAY NIGHT.
CONFIDENCE TABLE...
00-06Z 06-12Z 12-18Z 18-00Z
KCLT HIGH 81% MED 76% MED 62% HIGH 100%
KGSP MED 73% MED 68% MED 74% HIGH 100%
KAVL MED 71% MED 69% LOW 54% HIGH 100%
KHKY MED 75% MED 67% MED 64% HIGH 100%
KGMU MED 70% MED 73% MED 77% HIGH 100%
KAND MED 76% HIGH 80% HIGH 88% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR GAZ010-017-018-
026-028-029.
NC...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR NCZ033-048>053-
058-059-062>065-501>510.
SC...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR SCZ001>007-010-
011.
&&
$$
SYNOPSIS...JPT
NEAR TERM...NED/WIMBERLEY
SHORT TERM...HG
LONG TERM...JPT
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
845 PM CST WED NOV 18 2015
.DISCUSSION...
CLEAR SKIES PREVAIL ACROSS THE MIDSOUTH. A WEAK COLD FRONT IS
APPROACHING FROM THE NORTHWEST WHILE WEAK HIGH PRESSURE SITS OVER
THE LOWER MISSISSIPPI VALLEY. THE PRESSURE GRADIENT IS WEAK ACROSS
NORTHEAST MISSISSIPPI WHERE SKIES CLEARED OUT LATE. FOG IS
ALREADY DEVELOPING ACROSS MONROE COUNTY AND POINTS SOUTHEAST.
LATEST HRRR SHOWS FOG SPREADING ACROSS NORTHEAST MISSISSIPPI
OVERNIGHT. ADDED AREAS OF FOG TO THE FORECAST AND WILL NEED TO
MONITOR FOR A POSSIBLE DENSE FOG ADVISORY. THE PRESSURE GRADIENT
IS A LITTLE STRONGER OVER THE REMAINDER OF THE AREA...THANKS TO
THE APPROACHING FRONT...WHICH SHOULD HELP KEEP A LIGHT SOUTHWEST
WIND GOING AND LIMIT FOG POTENTIAL. OTRW FORECAST IS ON TRACK.
UPDATE ALREADY OUT.
SJM
&&
PREV DISCUSSION... /ISSUED 259 PM CST WED NOV 18 2015/
SKIES REMAIN CLOUDY OVER EASTERN SECTIONS OF THE FORECAST AREA
WITH MOSTLY SUNNY SKIES ELSEWHERE. TEMPERATURES THIS AFTERNOON
RANGE FROM THE MID 50S TO MID 60S. THE CLOUDS OVER EASTERN
SECTIONS OF THE FORECAST AREA WILL MOVE OUT THIS EVENING LEAVING
MOSTLY CLEAR TONIGHT. WINDS SHOULD NOT GO CALM OVERNIGHT SO IT
DOES NOT APPEAR THAT MUCH FOG WILL DEVELOP OVERNIGHT. TEMPERATURES
WILL COOL DOWN TO NEAR NORMAL LEVELS WITH LOWS THURSDAY MORNING IN
THE LOW TO MID 40S.
A SECOND COLD FRONT WILL PUSH THROUGH THE REGION ON THURSDAY. THE
AIR AHEAD OF THIS FRONT IS DRIER THAN THE FIRST FRONT SO NO RAIN
IS EXPECTED WITH THIS FRONT. TEMPERATURES WILL BE FAIRLY MILD
FOR MID-NOVEMBER WITH HIGHS IN THE UPPER 50S TO MID 60S. HIGH
PRESSURE WILL SETTLE INTO THE REGION THURSDAY NIGHT BRINGING
COLDER AIR INTO THE FORECAST AREA. LOWS FRIDAY MORNING WILL RANGE
FROM THE MID 30S TO LOWER 40S. HIGH PRESSURE WILL REMAIN NEAR THE
REGION ON FRIDAY WITH DRY WEATHER AND NEAR NORMAL TEMPERATURES.
BY FRIDAY NIGHT...ANOTHER COLD FRONT WILL MOVE INTO THE REGION BY
EARLY SATURDAY MORNING. THERE WILL BE SOME MOISTURE AHEAD OF THE
FRONT SO THERE COULD BE SOME SHOWERS LATE FRIDAY NIGHT OVER
NORTHWEST SECTIONS OF THE FORECAST AREA. AS THE FRONT MOVES
THROUGH THE REMAINDER OF THE FORECAST AREA ON SATURDAY MORE
SHOWERS WILL BE POSSIBLE MAINLY OVER NORTHERN SECTIONS.
TEMPERATURES WILL TURN COLDER BEHIND THE FRONT WITH HIGHS ON
SATURDAY IN THE UPPER 40S TO AROUND 60 DEGREES.
HIGH PRESSURE WILL BUILD INTO THE REGION SATURDAY NIGHT. THIS WILL
ALLOW TEMPERATURES TO DROP BELOW FREEZING OVER MUCH OF THE
FORECAST AREA SO THIS WILL LIKELY BE THE FIRST FREEZE FOR A LOT OF
THE AREA THAT DID NOT SEE BELOW FREEZING TEMPERATURES LAST
WEEKEND. HIGH PRESSURE WILL REMAIN OVER THE REGION ON SUNDAY
KEEPING THINGS UNSEASONABLY COOL WITH HIGHS MAINLY IN THE 40S.
SUNDAY NIGHT WILL BE ANOTHER CHILLY NIGHT WITH MOST LOCATIONS
SEEING TEMPERATURES NEAR OR BELOW FREEZING.
BY MONDAY...THE SURFACE HIGH WILL BE EAST OF THE REGION. THIS WILL
ALLOW WINDS TO SHIFT TO THE SOUTH AND BRING MILDER AIR INTO THE
FORECAST AREA. THIS WILL START A WARMING TREND WHICH WILL GO FROM
MONDAY THROUGH NEXT WEDNESDAY. A WEAK FRONTAL BOUNDARY WILL MOVE
INTO NORTHERN ARKANSAS NEXT WEDNESDAY WHICH COULD MEAN SOME RAIN
SHOWERS OVER WESTERN SECTIONS OF THE FORECAST AREA.
ARS
&&
.AVIATION...
00Z TAFS
MAINLY VFR CONDITIONS EXPECTED OVER THE NEXT 24 HOURS. WINDS
OVERNIGHT WILL BE FROM THE SOUTHWEST GENERALLY LESS THAN 6 KTS.
WINDS MAY DECOUPLE AT THE SURFACE AND GO CALM AT MKL AND TUP. IF
THEY DO...MVFR VSBYS WILL BE POSSIBLE AT BOTH SITES DUE TO FOG.
A DRY COLD FRONT WILL MOVE THROUGH THE REGION AFTER 19/13Z. WINDS
WILL SHIFT TO THE NORTHWEST AND WINDSPEEDS WILL INCREASE TO NEAR
10 KTS AT ALL SITES TOMORROW AFTERNOON.
AC3
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
321 PM CST TUE NOV 17 2015
.DISCUSSION...WINDS NOW BEGINNING TO PICK UP ACROSS THE AREA. GUSTS
OF BETWEEN 20 AND 30 MPH ARE NOW BEING REPORTED. WINDS ARE STRONG
BACK TO THE WEST AS WELL. UPPER LEVEL SYSTEM NOW STACKS RATHER
NICELY WITH THE SFC SYSTEM OVER THE CENTRAL PLAINS. INTENSIFICATION
IS ONGOING SO WE WILL CONTINUE TO SEE OUR GRADIENT TIGHTEN UP AS WE
PUSH INTO THIS EVENING.
LATEST HRRR MODEL HOLDS OFF WITH THE RAIN UNTIL AROUND 3AM FOR
OUR FAR WESTERN AREAS. THUS...A CONTINUING SPELL OF SUBSIDENCE OUT
AHEAD OF THE MAIN RAIN BAND WILL SERVE TO PERHAPS PROLONG THE
STRONGER WIND SPEEDS. FOR THAT REASON...WILL OPT TO TEMPORALLY
EXTEND THE WIND ADVISORY THOUGH 18Z ON WED.
OTW...A SOLID BAND OF HEAVY RAINFALL WITH PERHAPS A FEW EMBEDDED
TSTMS WILL PUSH ACROSS THE MID STATE WED MORNING. AS MENTIONED
PREVIOUSLY...THE RAIN WILL REACH THE TN RIVER AROUND 3AM AND FROM
THERE WILL REACH OUR PLATEAU COUNTIES SOMETIME BETWEEN 10 AM AND
NOON. THE MODERATE AND HEAVY RAINFALL WILL LAST FOR ABOUT 6 TO 8
HOURS AS IT WORKS EASTWARD. QPF AMOUNTS OF 1 TO 2 INCHES WILL BE
COMMON PLACE AND AS ALWAYS...LOCALIZED HEAVIER AMOUNTS AND MINOR
FLOODING WILL BE POSSIBLE. WILL CONTINUE TO INCLUDE A SLIGHT
CHANCE OF THUNDER AS WELL.
MOVING ON...THE LIGHTER SHOWER ACTIVITY WILL END ACROSS THE PLATEAU
DURING THE EARLY EVENING. DRY AND SEASONAL AIR WILL RETURN AFTER
THE SYSTEM PULLS EAST.
IN THE EXT FCST...A SERIES OF SHORTWAVES WILL MOVE EASTWARD ACROSS
THE EASTERN U.S.. HOWEVER...MIDDLE TN WILL BE ON THE SOUTHERN EDGE
OF EACH AXIS AND SO...ONLY SLIGHT CHANCES OF SHOWER ACTIVITY WILL
EXIST. THE ASSOCIATED COLD FRONT ON SATURDAY WILL USHER IN THE
COLDEST AIR OF THE SEASON THUS FAR. IN FACT...THE GFS ELUDES TO A
FEW SNOW FLURRIES WITH A WEAK SUNDAY NIGHT IMPULSE. BUT...SINCE THE
EURO IS DRY...WILL NOT INCLUDE ANY SNOW FLURRY CHANCES. OTW...LOOK
FOR BELOW NORMAL TEMPS...LOWS IN THE 20S TO NEAR 30...HIGHS UPPER
40S TO LOWER 50S.
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 64 68 46 62 / 60 100 10 0
CLARKSVILLE 61 67 43 61 / 90 100 10 0
CROSSVILLE 59 68 47 61 / 10 100 40 0
COLUMBIA 65 67 42 63 / 70 100 10 0
LAWRENCEBURG 64 65 43 63 / 70 100 10 0
WAVERLY 62 66 44 62 / 100 100 10 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON CST WEDNESDAY FOR TNZ005>011-023>034-
056>066-075-077>080-093>095.
&&
$$
21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
413 AM CST TUE NOV 17 2015
.DISCUSSION...
BIG CHANGES UNDERWAY ACROSS THE FORECAST AREA AS A POWERFUL STORM
SYSTEM IN THE PLAINS HEADS OUR WAY TONIGHT INTO TOMORROW. FOR THIS
MORNING...RADAR SHOWS A LARGE AREA OF LIGHT TO MODERATE RAIN WITH
A FEW EMBEDDED THUNDERSTORMS CONTINUES ACROSS WEST TENNESSEE INTO
NORTHWEST MIDDLE TENNESSEE IN ASSOCIATION WITH A LEAD SHORTWAVE
TROUGH. LATEST HRRR RUNS HAVE THIS ACTIVITY CONTINUING THROUGH
15Z OR SO BEFORE LIFTING OUT OF THE REGION...SO WILL SHOW
LIKELY/CATEGORICAL POPS FOR THE NORTHWEST COUNTIES FOR THE
MORNING...BUT ONLY SLIGHT CHANCE POPS FOR AN ISOLATED SHOWER OVER
THE WESTERN HALF DURING THE AFTERNOON DURING A LULL BETWEEN THE
INITIAL LEAD SHORTWAVE AND THE APPROACHING MAIN UPPER TROUGH.
STRENGTHENING WAA REGIME OVER THE TENNESSEE VALLEY WILL LEAD TO A
MUCH WARMER DAY FOR THE MID STATE WITH HIGHS IN THE UPPER 60S AND
70S ANTICIPATED...AND ANY BREAKS IN CLOUD COVER COULD RESULT IN
HIGHS BEING A FEW DEGREES WARMER THAN FORECAST.
PRESSURE GRADIENT WILL TIGHTEN SIGNIFICANTLY BETWEEN A 1035MB
SURFACE HIGH OVER THE NORTHEAST CONUS AND A 987MB SURFACE LOW OVER
OKLAHOMA BY THIS AFTERNOON...WITH SOUTHEAST WINDS ANTICIPATED TO
INCREASE INTO THE 10 TO 20 MPH RANGE WEST OF THE UPPER CUMBERLAND
REGION WITH OCCASIONAL GUSTS OVER 30 MPH. WINDS ARE EXPECTED TO
INCREASE FURTHER AS THE SURFACE HIGH REMAINS IN PLACE BUT THE
AFOREMENTIONED LOW MOVES INTO THE MIDWEST...WITH SOUTH-SOUTHEAST
WINDS OF 15 TO 25 MPH AND GUSTS TO AROUND 40 MPH TUESDAY EVENING
THROUGH TUESDAY NIGHT. WITH 850MB JET STRENGTHENING FROM 50KTS AT
00Z THIS EVENING UP TO 70-80KTS BY 12Z WEDNESDAY MORNING...A FEW
EVEN STRONGER GUSTS ARE CERTAINLY POSSIBLE. IN COORDINATION WITH
SURROUNDING OFFICES...A WIND ADVISORY HAS BEEN ISSUED FOR ALL
MID TN ZONES FOR THIS EVENING/TONIGHT. THE ADVISORY MAY NEED TO
BE EXTENDED OVER EASTERN ZONES THROUGH 18Z ON WEDNESDAY AS WINDS
WILL REMAIN BRISK THERE.
LATEST 00Z/06Z GUIDANCE IS A BIT SLOWER BRINGING THE QLCS
CURRENTLY OVER OKLAHOMA AND TEXAS INTO THE MID STATE...WITH THE
SLOWING AND WEAKENING QLCS REACHING THE TENNESSEE RIVER AROUND
09Z TONIGHT...I-65 AROUND 12Z...AND THE PLATEAU AROUND 19-20Z.
POPS HAVE BEEN ADJUSTED FOR TONIGHT/WEDNESDAY BASED ON THIS
TIMING. FORECAST SOUNDINGS CONTINUE TO SHOW VERY STRONG SHEAR
PROFILES BUT LITTLE OR ZERO CAPE...AND THUS NO SEVERE WEATHER IS
EXPECTED WITH MAINLY JUST MODERATE TO OCCASIONALLY HEAVY RAIN AND
A FEW ISOLATED STORMS. CANNOT COMPLETELY RULE OUT SOME
STRENGTHENING OF THE QLCS OVER EASTERN ZONES ON WEDNESDAY DUE TO
DAYTIME HEATING AS A COUPLE MODELS SUGGEST. LATEST MODEL AND WPC
QPF CONTINUES TO INDICATE 1 TO 3 INCHES OF RAIN FOR OUR
CWA...WHICH SHOULD NOT BE ENOUGH TO CAUSE ANY FLOODING ISSUES DUE
TO BELOW NORMAL RAINFALL THIS MONTH.
BEHIND THIS SYSTEM...COOLER AND DRIER WEATHER IS EXPECTED FOR
THURSDAY AND FRIDAY WITH TEMPERATURES GETTING CLOSER TO NORMAL FOR
THIS TIME OF YEAR. 00Z GUIDANCE HAS BECOME MORE AGGRESSIVE WITH A
STRONG COLD FRONT MOVING ACROSS THE AREA ON SATURDAY...WITH SOME
SPRINKLES ALONG THE FRONT AND THE COLDEST AIR YET THIS FALL BEHIND
IT. HAVE LOWERED TEMPERATURES CONSIDERABLY FOR SUNDAY THROUGH THE
REST OF THE FORECAST PERIOD CLOSE TO THE CONSENSUS BLEND OF
GUIDANCE...BUT NOT NEARLY AS COLD AS SOME OF THE GUIDANCE SUCH AS
THE MEX MOS.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 71 63 67 45 / 40 60 100 10
CLARKSVILLE 70 62 64 44 / 80 90 100 10
CROSSVILLE 67 60 65 45 / 10 10 100 40
COLUMBIA 71 63 64 42 / 40 70 100 10
LAWRENCEBURG 70 62 63 43 / 40 70 100 10
WAVERLY 71 61 62 45 / 80 100 100 10
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 6 PM THIS EVENING TO 6 AM CST WEDNESDAY FOR
TNZ005>011-023>034-056>066-075-077>080-093>095.
&&
$$
SHAMBURGER
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1134 PM CST MON NOV 16 2015
.DISCUSSION...
06Z TAF DISCUSSION IN AVIATION SECTION.
&&
.AVIATION...
CHANGES FROM 00Z TAFS...OVERALL TRENDS LOOK ON TRACK. THINK
MVFR/IFR CIGS LOOK GOOD FOR THE NEXT 6-12HRS AHEAD OF SQUALL LINE.
SQUALL LINE IS ORGANIZING IN W C TX. MODELS DEPICT CONVECTION
FORMING AHEAD OF THIS SQUALL LINE FROM 10-15Z WITH SQUALL LINE
COMING INTO THE AREA 13-21Z TIME FRAME. TAFS REFLECT A LITTLE
FASTER PROGRESSION THAN MODELS WHICH COULD HAPPEN. LATEST HRRR RUN
SEEMS TO AGREE WITH THESE TRENDS. LATEST 00Z WRF ARW/NMM SHOW
SIMILAR TRENDS BUT ARE ALSO MORE AGGRESSIVE WITH CONVECTION AHEAD
OF THE MAIN LINE OF STORMS. OVERALL MODEL AGREEMENT IS FAIRLY GOOD
LEADING TO INCREASED CONFIDENCE. MAIN TAF UPDATES GOING FORWARDS
WILL BE TO KEEP UP WITH THESE TRENDS.
39
&&
.PREV DISCUSSION... /ISSUED 921 PM CST MON NOV 16 2015/
DISCUSSION...
ORGANIZING WEST TEXAS SQUALL LINE IS STILL ON SCHEDULE TO MOVE INTO
THE WESTERN EDGES OF SOUTHEAST TEXAS TOWARD SUNRISE (GIVE OR TAKE AN
HOUR OR TWO) TOMORROW MORNING. STRONG/SEVERE CELL DEVELOPMENT IS POSSIBLE
DURING THE OVERNIGHT HOURS AHEAD OF THIS LINE TOO. STILL LOOKS LIKE
STRONG DAMAGING WINDS AND ISOLATED TORNADOES ARE THE PRIMARY SEVERE
WEATHER THREATS WITH THIS SYSTEM. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE
TOO. EVERYTHING SHOULD CLEAR OUT OF THE AREA FROM WEST TO EAST DURING
THE LATE MORNING THROUGH AFTERNOON HOURS. CURRENT FORECAST PACKAGE HAS
15 TO 25 MPH WINDS FOR TONIGHT AND EARLY TOMORROW ACROSS A LARGE PART
OF THE AREA. WILL CONTINUE TO MONITOR FOR A POSSIBLE WIND ADVISORY IF
SPEEDS CREEP UP HIGHER THAN ANTICIPATED. 42
PREV DISCUSSION... /ISSUED 615 PM CST MON NOV 16 2015/
DISCUSSION...
00Z TAF DISCUSSION IN AVIATION SECTION.
AVIATION...
SUMMARY...SHOWERS WITH MVFR/IFR CIGS MIX TONIGHT UNTIL SHRA/TSRA
BEGIN TO FILL IN OVER THE AREA OVERNIGHT INTO EARLY MORNING HOURS.
SQUALL IN FROM C TX MOVES INTO THE AREA FROM 12 TO 21Z TUESDAY.
TIMING OF SQUALL LINE BASED MAINLY ON EXTRAPOLATE HRRR/RAP WITH
WRF ARW/NMM SOLUTIONS. NAM SEEMS TO BE TOO SLOW. MAYBE A BIT
FASTER THAN THE GFS. LLJ WILL BE QUITE STRONG NEAR 50KTS AT
925-850MB SO INCLUDED SOME GUSTS OVERNIGHT WITH WINDS. OTHERWISE
IF WINDS HAPPEN TO DECOUPLE...LLWS WILL BE NEEDED.
KCLL/KUTS/KCXO...BASICALLY LOOKING AT SOME LOWER CIGS THROUGH MUCH
OF THE TAF PERIOD UNTIL AFTER THE SQUALL LINE PUSHES THROUGH.
MAY GET SOME SHRA/TSRA TO FORM AHEAD OF A SQUALL LINE FROM 06Z TO
09Z WITH A LULL IN ACTIVITY UNTIL THE SQUALL LINE. SQUALL LINE
COULD MOVE INTO KCLL AS EARLY AS 11Z AND THEN KUTS/KCXO A LITTLE
LATER AT 13-14Z. TSRA COULD HOLD ON THROUGH ABOUT 18Z WHEN ANY
LINGERING TSRA/SHRA MOVE OUT. CIGS SHOULD IMPROVE AFTER THAT FOR
THE AFTERNOON. SOUTHERLY WINDS WILL BE QUITE GUSTY TO MAYBE 30KTS
AHEAD OF THE SQUALL LINE.
KIAH/KHOU/KSGR...MVFR POSSIBLY SOME IFR CIGS WILL BE POSSIBLE
THROUGH THE MORNING HOURS WITH SOME SHRA. POSSIBLE THAT SOME
SHRA/TSRA FORM AHEAD OF A SQUALL LINE SO MENTION THAT IN FIRST
TEMPO GROUP WITH POSSIBLE IFR CIGS. MAY GET A BREAK IN ACTIVITY
UNTIL SQUALL LINE MOVES THROUGH LATE MORNING HOURS 16-19Z WITH
GUSTY WINDS. WINDS WILL BE GUSTY FROM THE SOUTH ANYWAY. TSRA
SHOULD DROP OFF EARLY AFTERNOON WITH THE SQUALL LINE PROGRESSING
EAST. CIGS IMPROVE TOMORROW EVENING AND OVERNIGHT.
KGLS/KLBX...LOOK FOR GUSTY WINDS OFF THE GULF WITH MAYBE SOME
LOWER VSBY AT KGLS DUE TO LIGHT SEA FOG/HAZE. MVFR/IFR CIGS
POSSIBLE THROUGH THE MORNING HOURS WITH PASSING SHRA. LOOK FOR
MAYBE SOME PASSING TSRA AHEAD OF THE SQUALL LINE BUT THIS ACTIVITY
MAY BE FURTHER INLAND THAN ALONG THE COAST. MAIN LINE OF STORM
SHOULD REACH KLBX/KGLS AROUND 17Z THROUGH EARLY AFTERNOON.
TSRA/SHRA MAY LINGER UNTIL AFTER 21Z BUT COULD END SOONER.
39
MARINE...
PRES GRADIENT REALLY TIGHTENS OVERNIGHT AND ANTICIPATE ONSHORE WINDS
TO INCREASE TO ADVSY LEVELS...QUITE POSSIBLY WITH SOME GUSTS TO NEAR
GALE FORCE DURING THE OVERNIGHT & EARLY MORNING HOURS TUE. WILL
HOIST THE ADVSY FLAGS FOR ALL THE WATERS BEGINNING THIS EVENING.
LINE OF STORMS SHOULD MOVE WNW-ESE THRU THE WATERS FROM THE LATE
MORNING THRU THE MID/LATE AFTN HOURS. ASSOCIATED STRONG TO SEVERE
STORMS A GOOD POSSIBILITY. WINDS SHIFT TO THE NW BEHIND THE
CONVECTION...BUT DIMINISH LATE TUE NIGHT AND WEDNESDAY.
TIDES LEVELS ARE RUNNING ABOUT 1.25 FT ABOVE NORMAL. HIGH TIDE ALONG
THE GALVESTON BEACHES IS AROUND 8 PM. THIS WOULD PUT LEVELS RIGHT
AROUND 3.3 FEET THEN...BUT LUCKILY THIS IS BEFORE WINDS AND SEAS
REALLY START CRANKING UP OVERNIGHT. SO OTHER THAN POSSIBLY SOME WAVE
RUN UP TO HIGHWAY 87@124 LATE TONIGHT...DON`T REALLY SEE ANY OTHER
SIGNIFICANT ISSUES AS LEVELS WILL TREND TOWARD LOW TIDE AROUND
1230PM TOMORROW. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 66 69 48 70 49 / 80 100 0 0 0
HOUSTON (IAH) 73 74 50 73 49 / 50 100 20 0 0
GALVESTON (GLS) 72 74 57 71 60 / 30 90 40 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 6 PM CST TUESDAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...42
AVIATION/MARINE...39
AREA FORECAST DISCUSSION
NWS ALBANY NY
1243 AM EST THU NOV 19 2015
.SYNOPSIS...
A WARM FRONT WILL WORK ACROSS OUR REGION TONIGHT...KEEPING
TEMPERATURES MILD UNDER A CANOPY OF INCREASING CLOUDS. SPOTTY
DRIZZLE WILL BREAK OUT EARLY THURSDAY...FOLLOWED BY HEAVIER
SHOWERS LATER IN THE DAY WHICH WILL BE AHEAD OF A COLD FRONT THAT
WILL CROSS OUR REGION THURSDAY NIGHT. COOLER DRIER AIR WILL FOLLOW
FOR FRIDAY... FOLLOWED BY EVEN COLDER AIR AND SOME SHOWERS OF RAIN
OR SNOW FOR LATER IN THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
CLOUDS AND SLOWLY INCREASING WINDS THROUGH THE EARLY MORNING
HOURS. SOME INDICATIONS OF SOME SPOTTY LIGHT RAIN AND DRIZZLE IN
SOME AREAS...SHOULD VERY GRADUALLY INCREASE IN COVERAGE TOWARD
DAYBREAK...BUT STILL JUST CHANCES. THE MORE WIDESPREAD RAIN IS
SEEN IN WESTERN NY AND WILL AFFECT OUR REGION THROUGH THE DAY.
TEMPERATURES HAVE REACHED THEIR LOWS IN THE UPPER 40S TO LOWER
50S...AND SLOWLY RISE THROUGH SUNRISE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
BY THURSDAY...OUR WHOLE AREA WILL BE IN A MOIST MILD AIR MASS
WITH A COLD FRONT RAPIDLY APPROACHING FROM THE WEST.
THIS IS THE SAME SYSTEM THAT PRODUCED QUITE AN ARRAY OF FOUL WEATHER
OUT WEST...INCLUDING SEVERE WEATHER AND EVEN BLIZZARD CONDITIONS.
NEITHER IS EXPECTED FOR US (INSTABILITY NOT THERE FOR ANY REAL
CONVECTION). A RUMBLE OF THUNDER IS CERTAINLY POSSIBLE BUT WITH
SHOWALTER VALUES >0 AND CAPE VALUES NEAR 0 J/KG WILL KEEP
ANY MENTION OF THUNDERSTORMS OUT OF THE GRIDS FOR NOW.
THAT SAID...WITH PWATS SOARING PAST AN INCH....TWO STANDARDS ABOVE
NORMAL. THE COMBINATION OF THIS MOISTURE...THE FRONT...SHORTWAVE
ENERGY AND OUR AREA COMING UNDER THE DIVERGENT AREA OF THE RR 100KT
NIGHT BY EVENING...ALL POINT TO ROUND OF SHOWERS...SOME CONTAINING
MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL.
WHAT IS A LITTLE DIFFERENT FROM PREVIOUS RUNS...THERE IS LESS OF TENDENCY FOR
A SECONDARY WAVE TO DEVELOP ALONG THE TRIPLE POINT...AS THERE WAS
IN SOME EARLIER RUNS. IT LOOKS LIKE A PROGRESSIVE SYSTEM...PRETTY MUCH
WHAT WE HAVE SEEN THIS AUTUMN.
A GUSTY SOUTH WIND WILL ENSUE ON THURSDAY...10-15 MPH...WITH GUSTS
25-35 MPH ACROSS PORTIONS OF THE HIGHER TERRAIN...AND EVEN
SOME SECTIONS OF THE CAPITAL REGION AND MOHAWK VALLEY. DURING
HEAVY SHOWERS...IT IS REMOTELY POSSIBLE THAT SOME GUSTS COULD EVEN
REACH A LITTLE HIGHER THAN THAN THAT...BUT JUST BRIEFLY.
THEREFORE...NO WIND HEADLINES WERE ASSIGNED WITH THIS PACKAGE.
THE ACTUAL COLD FRONT LOOKS TO MOVE ON THROUGH THURSDAY EVENING...
FOLLOWED BY HIGH PRESSURE BEGINNING TO BUILD IN BY EARLY FRIDAY.
IN FACT...THE SKY MIGHT ACTUALLY CLEAR BY DAYBREAK FRIDAY OR AT
LEAST PARTIALLY CLEAR.
BASED ON UPSTREAM TEMPERATURES WELL INTO THE 60S...WE WILL GO SLIGHTLY
HIGHER THAN ALL MACHINE GUIDANCE ON THURSDAY. LOOK FOR HIGHS LOWER TO MID
60S IN THE VALLEYS...MID OR UPPER 50S EVEN ACROSS THE HIGHER TERRAIN.
TURNING COOLER...BUT STILL ABOVE NORMAL THURSDAY NIGHT WITH LOWS
RANGING FROM THE UPPER 30S TO MID 40S.
FRIDAY SHOULD FEATURE AT LEAST PARTIAL SUNSHINE AS THE FLOW LOOKS TOO ANTI-
CYCLONIC FOR MUCH LAKE INDUCED CLOUDS (OUTSIDE OF THE ADIRONDACKS WHERE
UPSLOPE CLOUDS AND A FEW SHOWERS OF RAIN OR RAIN AND WET SNOW MIXED ARE
POSSIBLE).
HIGH TEMPERATURES WILL BE NOTICEABLY COOLER THAN THURSDAY...HIGHS NEAR 50
IN THE VALLEYS...LOWER TO MID 40S HIGHER TERRAIN...CLOSER TO 40
ACROSS THE ADIRONDACKS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE EXTENDED OPENS WITH A POTENT UPPER LEVEL TROUGH APPROACHING FROM
THE GREAT LAKES REGION AND THE MIDWEST. THE UPPER LEVEL TROUGH
TURNS NEGATIVELY TILTED ACCORDING TO LATEST GFS/ECMWF...AS THE SFC
CYCLONE LIFTS NORTHEAST ACROSS THE ERN GREAT LAKES REGION INTO SE
ONTARIO BY 12Z SUN. THERE IS ENOUGH MOISTURE WITH THE OCCLUDED
FRONT TO THE SYSTEM FOR A PERIOD OF RAIN SHOWERS TRANSITIONING TO
SNOW SHOWERS. THERE IS DECENT LIFT AND CONVERGENCE WITH THE
BOUNDARY. SOME LIGHT SNOW ACCUMULATIONS ARE POSSIBLE WITH A COATING
TO LESS THAN A HALF AN INCH IN THE VALLEY AREAS...AND AN INCH OR TWO
OVER THE HIGHER TERRAIN. THE LIGHT SNOW IS SUPPORTED FROM SOME OF
THE ENSEMBLES. THE LATEST GEFS PLUME DIAGRAM YIELDS ABOUT A TENTH OF
AN INCH OF SNOWFALL FOR ALBANY WITH PERHAPS A HALF DOZEN MEMBERS OR
SO. LOWS SAT NIGHT WILL RANGE FROM THE MID AND U20S OVER THE MTNS TO
U20S TO L30S OVER THE VALLEYS.
SUNDAY WILL BE A BLUSTERY AND COLD DAY WITH THE LONG-WAVE TROUGH
AXIS APPROACHING THE REGION. A SECONDARY COLD FRONT OR SFC TROUGH
WILL MOVE THROUGH WITH H850 TEMPS FALL TO -7C TO -10C. SOME SCT
SNOW AND RAIN SHOWERS ARE POSSIBLE. THE RAIN SHOWERS WILL BE MAINLY
WHERE THE BOUNDARY LAYER WARMS ENOUGH WITH TEMPS IN THEN 40-45F
RANGE. THE HIGHER POPS WILL BE NORTH AND WEST OF THE CAPITAL
DISTRICT AND THE MOHAWK RIVER VALLEY. SOME ADDITIONAL LIGHT SNOW
ACCUMS ARE POSSIBLE OVER THE WRN DACKS...ERN CATSKILLS...AND SRN
GREENS. HIGHS WILL BE MAINLY IN THE U30S TO L40S IN THE
VALLEYS...AND LOWER TO U30S OVER THE HIGHER TERRAIN...EXCEPT SOME
U20S IN THE SRN DACKS.
SUNDAY NIGHT INTO MONDAY...A COLD AIR MASS BUILDS IN FROM THE OHIO
VALLEY WITH SOME LAKE EFFECT SNOWFALL POSSIBLE BASED ON THE MEDIUM
RANGE GUIDANCE. LOCATIONS IN THE WRN DACKS...AND W-CNTRL MOHAWK
VALLEY MAY GET AT LEAST SOME LIGHT SNOW ACCUMS. THE REST OF THE FCST
AREA WILL REMAIN DRY...BUT COLD. THE LATEST GFS H850 TEMPS FALL TO
-10C TO -13C OVER THE FCST AREA. LOWS WILL BE IN THE MID AND U20S IN
THE VALLEYS...AND TEENS TO L20S OVER THE MTNS. HIGHS ON MONDAY
RANGE FROM THE U30S TO L40S IN THE VALLEY AREAS...AND U20S TO M30S
OVER THE MTNS.
MONDAY NIGHT INTO TUESDAY...THE LAKE EFFECT SNOWFALL SHOULD
TAPER...AS THE FLOW BECOMES MORE ZONAL. A WEAK DISTURBANCE IN THE
ZONAL FLOW COULD BRING A SLIGHT CHC OF SHOWERS TUE AFTERNOON WEST OF
THE MOHAWK VALLEY. THE ECMWF REMAINS DRY. TEMPS MODERATE TO
SEASONAL VALUES ON TUESDAY WITH SOME MID AND U40S IN THE CAPITAL
DISTRICT...TACONICS...MID HUDSON VALLEY...AND NW CT. U30S TO L40S
ARE COMMON NORTH AND WEST.
TUESDAY NIGHT INTO WEDNESDAY...HIGH PRESSURE WILL RIDGE BACK IN OVER
THE NORTHEAST WITH FAIR AND DRY WEATHER FOR THE MID WEEK...AND
SEASONABLE TEMPS.
OVERALL...TEMPS WILL AVERAGE NEAR NORMAL WITH PCPN BELOW NORMAL IN
THE LONG TERM.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AN OCCLUDED FRONT WILL APPROACH FROM THE WEST LATER THIS
AFTERNOON...AND MOVE ACROSS THE TAF SITES THIS EVENING.
THROUGH 12Z/THU...MVFR CIGS...WHICH HAVE ALREADY OVERSPREAD THE
TAF SITES...SHOULD PERSIST. THE ONE EXCEPTION WILL BE AT
KPSF...WHERE CIGS SHOULD BE MAINLY IFR. THERE COULD BE SOME SPOTTY
DRIZZLE DEVELOPING TOWARD 12Z...WHICH COULD LEAD TO ADDITIONAL
MVFR VSBYS...AND BORDERLINE MVFR/IFR CIGS.
AFTER 12Z/THU...MVFR/IFR CIGS SHOULD TREND TO MAINLY IFR...WITH
VSBYS MAINLY IN THE MVFR RANGE THROUGH THE END OF THE TAF PERIOD
AT 06Z/FRI. OCCASIONAL IFR VSYBS COULD OCCUR DURING MODERATE/HEAVY
RAIN SHOWERS LATER THIS AFTERNOON INTO EARLY TONIGHT.
THE OCCLUDED FRONT IS EXPECTED TO PASS THROUGH THE TAF SITES
ROUGHLY IN THE 03Z-05Z/FRI TIME PERIOD. A PERIOD OF HEAVIER RAIN
SHOWERS AND GUSTY WINDS WILL IMMEDIATELY PRECEDE AND ACCOMPANY ITS
PASSAGE.
WINDS WILL REMAIN FROM THE SOUTHEAST TO SOUTH AT GENERALLY 8-12 KT
THROUGH MIDDAY...WITH OCCASIONAL GUSTS OF 12-22 KT...STRONGEST AT
KALB. THEN...WIND SPEEDS WILL INCREASE SLIGHTLY TO 10-15 KT THIS
AFTERNOON...WITH GUSTS OF 18-25 KT LIKELY...PERHAPS EVEN STRONGER
AT TIMES AT KALB...AND ALSO WHEN THE FRONT MOVES THROUGH EARLY
THURSDAY NIGHT. WHEN THE FRONT PASSES...THE WINDS WILL SHIFT INTO
THE SOUTHWEST TO WEST. BEHIND THE FRONT...SOUTHWEST TO WEST WINDS
WILL DECREASE SLIGHTLY...MAINLY INTO THE 5-10 KT RANGE.
LOW LEVEL WIND SHEAR WILL REMAIN LIKELY THROUGH AT LEAST SUNRISE
AT KGFL AND KPOU...WHERE SFC WINDS WILL BE SOMEWHAT LIGHTER FROM
THE SOUTHEAST TO SOUTH AT 8-12 KT...WHILE WINDS AROUND 2000 FT AGL
REMAIN FROM THE SOUTH AT 30-40 KT. AS SFC WINDS INCREASE AFTER
SUNRISE...THE THREAT FOR LOW LEVEL WIND SHEAR SHOULD DECREASE.
OUTLOOK...
FRIDAY - SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA...SHSN.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A SOAKING RAINFALL IS EXPECTED MAINLY THURSDAY AFTERNOON THROUGH
THURSDAY NIGHT. WE DID NOT ASSIGN A "WET FLAG" TO OUR NFDRS
SINCE THE BULK OF THE RAIN WILL NOT FALL UNTIL AFTER 100 PM
THURSDAY.
RAINFALL AMOUNTS SHOULD BE A QUARTER INCH OR MORE EVERYWHERE.
IT DRIES OUT FRIDAY WITH A NORTHWEST WIND 5- 15 MPH.
ANOTHER CLIPPER TYPE SYSTEM COULD BRING RAIN OR SNOW SHOWERS
SATURDAY NIGHT...ESPECIALLY NORTH AND WEST OF ALBANY. THERE
MIGHT BE SOME MINOR ACCUMULATIONS OF SNOW.
MUCH COLDER AIR WORKS IN ON GUSTY WINDS FOR THE LATER PORTION OF THE
WEEKEND.
&&
.HYDROLOGY...
A COLD FRONT WILL BRING A ROUND OF RAIN SHOWERS TO THE REGION
LATER THURSDAY INTO THURSDAY NIGHT.
THIS IS A PROGRESSIVE SYSTEM...SO IT WILL NOT LINGER TOO LONG.
IT DRIES OUT BY FRIDAY.
RAINFALL AMOUNTS LOOK TO BE HALF AN INCH TO AROUND AN INCH IN
THE VALLEYS...POSSIBLY UP TO TWO INCHES ACROSS THE HIGHER TERRAIN...
OF THE SOUTHERN GREENS AND BERKSHIRES.
THIS RAIN WILL PRODUCE WITHIN BANK RISES...MAYBE A FEW SPOTS
APPROACHING ACTION STAGE. NO FLOODING EXPECTED.
COOLER AND DRIER WEATHER WILL RETURN FRIDAY INTO THE FIRST HALF
OF THE WEEKEND. ANOTHER SYSTEM MAY BRING LIGHT PCPN IN THE FORM OF
RAIN/SNOW SHOWERS SATURDAY NIGHT INTO SUNDAY WITH LITTLE OR NO HYDROLOGICAL
IMPACTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/GJM
NEAR TERM...HWJIV/NAS
SHORT TERM...HWJIV/KL
LONG TERM...WASULA
AVIATION...KL
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV/KL/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1220 AM EST THU NOV 19 2015
.SYNOPSIS...
A WARM FRONT WILL WORK ACROSS OUR REGION TONIGHT...KEEPING
TEMPERATURES MILD UNDER A CANOPY OF INCREASING CLOUDS. SPOTTY
DRIZZLE WILL BREAK OUT EARLY THURSDAY...FOLLOWED BY HEAVIER
SHOWERS LATER IN THE DAY WHICH WILL BE AHEAD OF A COLD FRONT THAT
WILL CROSS OUR REGION THURSDAY NIGHT. COOLER DRIER AIR WILL FOLLOW
FOR FRIDAY... FOLLOWED BY EVEN COLDER AIR AND SOME SHOWERS OF RAIN
OR SNOW FOR LATER IN THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
CLOUDS AND SLOWLY INCREASING WINDS THROUGH THE EARLY MORNING
HOURS. SOME INDICATIONS OF SOME SPOTTY LIGHT RAIN AND DRIZZLE IN
SOME AREAS...SHOULD VERY GRADUALLY INCREASE IN COVERAGE TOWARD
DAYBREAK...BUT STILL JUST CHANCES. THE MORE WIDESPREAD RAIN IS
SEEN IN WESTERN NY AND WILL AFFECT OUR REGION THROUGH THE DAY.
TEMPERATURES HAVE REACHED THEIR LOWS IN THE UPPER 40S TO LOWER
50S...AND SLOWLY RISE THROUGH SUNRISE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
BY THURSDAY...OUR WHOLE AREA WILL BE IN A MOIST MILD AIR MASS
WITH A COLD FRONT RAPIDLY APPROACHING FROM THE WEST.
THIS IS THE SAME SYSTEM THAT PRODUCED QUITE AN ARRAY OF FOUL WEATHER
OUT WEST...INCLUDING SEVERE WEATHER AND EVEN BLIZZARD CONDITIONS.
NEITHER IS EXPECTED FOR US (INSTABILITY NOT THERE FOR ANY REAL
CONVECTION). A RUMBLE OF THUNDER IS CERTAINLY POSSIBLE BUT WITH
SHOWALTER VALUES >0 AND CAPE VALUES NEAR 0 J/KG WILL KEEP
ANY MENTION OF THUNDERSTORMS OUT OF THE GRIDS FOR NOW.
THAT SAID...WITH PWATS SOARING PAST AN INCH....TWO STANDARDS ABOVE
NORMAL. THE COMBINATION OF THIS MOISTURE...THE FRONT...SHORTWAVE
ENERGY AND OUR AREA COMING UNDER THE DIVERGENT AREA OF THE RR 100KT
NIGHT BY EVENING...ALL POINT TO ROUND OF SHOWERS...SOME CONTAINING
MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL.
WHAT IS A LITTLE DIFFERENT FROM PREVIOUS RUNS...THERE IS LESS OF TENDENCY FOR
A SECONDARY WAVE TO DEVELOP ALONG THE TRIPLE POINT...AS THERE WAS
IN SOME EARLIER RUNS. IT LOOKS LIKE A PROGRESSIVE SYSTEM...PRETTY MUCH
WHAT WE HAVE SEEN THIS AUTUMN.
A GUSTY SOUTH WIND WILL ENSUE ON THURSDAY...10-15 MPH...WITH GUSTS
25-35 MPH ACROSS PORTIONS OF THE HIGHER TERRAIN...AND EVEN
SOME SECTIONS OF THE CAPITAL REGION AND MOHAWK VALLEY. DURING
HEAVY SHOWERS...IT IS REMOTELY POSSIBLE THAT SOME GUSTS COULD EVEN
REACH A LITTLE HIGHER THAN THAN THAT...BUT JUST BRIEFLY.
THEREFORE...NO WIND HEADLINES WERE ASSIGNED WITH THIS PACKAGE.
THE ACTUAL COLD FRONT LOOKS TO MOVE ON THROUGH THURSDAY EVENING...
FOLLOWED BY HIGH PRESSURE BEGINNING TO BUILD IN BY EARLY FRIDAY.
IN FACT...THE SKY MIGHT ACTUALLY CLEAR BY DAYBREAK FRIDAY OR AT
LEAST PARTIALLY CLEAR.
BASED ON UPSTREAM TEMPERATURES WELL INTO THE 60S...WE WILL GO SLIGHTLY
HIGHER THAN ALL MACHINE GUIDANCE ON THURSDAY. LOOK FOR HIGHS LOWER TO MID
60S IN THE VALLEYS...MID OR UPPER 50S EVEN ACROSS THE HIGHER TERRAIN.
TURNING COOLER...BUT STILL ABOVE NORMAL THURSDAY NIGHT WITH LOWS
RANGING FROM THE UPPER 30S TO MID 40S.
FRIDAY SHOULD FEATURE AT LEAST PARTIAL SUNSHINE AS THE FLOW LOOKS TOO ANTI-
CYCLONIC FOR MUCH LAKE INDUCED CLOUDS (OUTSIDE OF THE ADIRONDACKS WHERE
UPSLOPE CLOUDS AND A FEW SHOWERS OF RAIN OR RAIN AND WET SNOW MIXED ARE
POSSIBLE).
HIGH TEMPERATURES WILL BE NOTICEABLY COOLER THAN THURSDAY...HIGHS NEAR 50
IN THE VALLEYS...LOWER TO MID 40S HIGHER TERRAIN...CLOSER TO 40
ACROSS THE ADIRONDACKS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE EXTENDED OPENS WITH A POTENT UPPER LEVEL TROUGH APPROACHING FROM
THE GREAT LAKES REGION AND THE MIDWEST. THE UPPER LEVEL TROUGH
TURNS NEGATIVELY TILTED ACCORDING TO LATEST GFS/ECMWF...AS THE SFC
CYCLONE LIFTS NORTHEAST ACROSS THE ERN GREAT LAKES REGION INTO SE
ONTARIO BY 12Z SUN. THERE IS ENOUGH MOISTURE WITH THE OCCLUDED
FRONT TO THE SYSTEM FOR A PERIOD OF RAIN SHOWERS TRANSITIONING TO
SNOW SHOWERS. THERE IS DECENT LIFT AND CONVERGENCE WITH THE
BOUNDARY. SOME LIGHT SNOW ACCUMULATIONS ARE POSSIBLE WITH A COATING
TO LESS THAN A HALF AN INCH IN THE VALLEY AREAS...AND AN INCH OR TWO
OVER THE HIGHER TERRAIN. THE LIGHT SNOW IS SUPPORTED FROM SOME OF
THE ENSEMBLES. THE LATEST GEFS PLUME DIAGRAM YIELDS ABOUT A TENTH OF
AN INCH OF SNOWFALL FOR ALBANY WITH PERHAPS A HALF DOZEN MEMBERS OR
SO. LOWS SAT NIGHT WILL RANGE FROM THE MID AND U20S OVER THE MTNS TO
U20S TO L30S OVER THE VALLEYS.
SUNDAY WILL BE A BLUSTERY AND COLD DAY WITH THE LONG-WAVE TROUGH
AXIS APPROACHING THE REGION. A SECONDARY COLD FRONT OR SFC TROUGH
WILL MOVE THROUGH WITH H850 TEMPS FALL TO -7C TO -10C. SOME SCT
SNOW AND RAIN SHOWERS ARE POSSIBLE. THE RAIN SHOWERS WILL BE MAINLY
WHERE THE BOUNDARY LAYER WARMS ENOUGH WITH TEMPS IN THEN 40-45F
RANGE. THE HIGHER POPS WILL BE NORTH AND WEST OF THE CAPITAL
DISTRICT AND THE MOHAWK RIVER VALLEY. SOME ADDITIONAL LIGHT SNOW
ACCUMS ARE POSSIBLE OVER THE WRN DACKS...ERN CATSKILLS...AND SRN
GREENS. HIGHS WILL BE MAINLY IN THE U30S TO L40S IN THE
VALLEYS...AND LOWER TO U30S OVER THE HIGHER TERRAIN...EXCEPT SOME
U20S IN THE SRN DACKS.
SUNDAY NIGHT INTO MONDAY...A COLD AIR MASS BUILDS IN FROM THE OHIO
VALLEY WITH SOME LAKE EFFECT SNOWFALL POSSIBLE BASED ON THE MEDIUM
RANGE GUIDANCE. LOCATIONS IN THE WRN DACKS...AND W-CNTRL MOHAWK
VALLEY MAY GET AT LEAST SOME LIGHT SNOW ACCUMS. THE REST OF THE FCST
AREA WILL REMAIN DRY...BUT COLD. THE LATEST GFS H850 TEMPS FALL TO
-10C TO -13C OVER THE FCST AREA. LOWS WILL BE IN THE MID AND U20S IN
THE VALLEYS...AND TEENS TO L20S OVER THE MTNS. HIGHS ON MONDAY
RANGE FROM THE U30S TO L40S IN THE VALLEY AREAS...AND U20S TO M30S
OVER THE MTNS.
MONDAY NIGHT INTO TUESDAY...THE LAKE EFFECT SNOWFALL SHOULD
TAPER...AS THE FLOW BECOMES MORE ZONAL. A WEAK DISTURBANCE IN THE
ZONAL FLOW COULD BRING A SLIGHT CHC OF SHOWERS TUE AFTERNOON WEST OF
THE MOHAWK VALLEY. THE ECMWF REMAINS DRY. TEMPS MODERATE TO
SEASONAL VALUES ON TUESDAY WITH SOME MID AND U40S IN THE CAPITAL
DISTRICT...TACONICS...MID HUDSON VALLEY...AND NW CT. U30S TO L40S
ARE COMMON NORTH AND WEST.
TUESDAY NIGHT INTO WEDNESDAY...HIGH PRESSURE WILL RIDGE BACK IN OVER
THE NORTHEAST WITH FAIR AND DRY WEATHER FOR THE MID WEEK...AND
SEASONABLE TEMPS.
OVERALL...TEMPS WILL AVERAGE NEAR NORMAL WITH PCPN BELOW NORMAL IN
THE LONG TERM.
&&
.AVIATION /05Z THURSDAY THROUGH MONDAY/...
MVFR CIGS ALREADY OCCURRING AT KPOU/KPSF...AND EXPECT MVFR CIGS TO
MOVE INTO KALB ND KGFL BEFORE MIDNIGHT. THEN MVFR CIGS AND
POSSIBLE MVFR VSBYS WILL OCCUR FOR THE REST OF THE NIGHT AS SOME
FOG OR DRIZZLE DEVELOPS ACROSS THE REGION. IFR CIGS ARE ALSO
POSSIBLE AT KPOU/KPSF LATE TONIGHT...ESPECIALLY AT KPSF WHERE THE
IFR CIGS COULD START AROUND 06Z.
MVFR/IFR CIGS WILL PERSIST INTO THE MORNING...BUT THE DRIZZLE AND
FOG WILL GIVE WAY TO MORE SHOWERY PCPN AS THE COLD FRONT
APPROACHES FROM THE WEST. EXPECT THE WIDESPREAD SHOWERS TO BEGINN
AROUND 15Z/16Z...WITH IFR CIGS AND MVFR VSBYS OCCURING AT ALL THE
TAF SITES THROUGH THE REST OF THE TAF PERIOD ENDING AT 00Z FRIDAY.
A SOUTH BREEZE WILL CONTINUE AT ALL THE TAF SITES THROUGH THE PERIOD.
THE WIND WILL AVERAGE 10KTS AT ALL THE TAF SITES...WITH SOME
HIGHER GUSTS POSSIBLE...ESPECIALLY LATER ON THURSDAY.
A COLD FRONT WILL CROSS THE TAF SITES BUT NOT UNTIL THURSDAY NIGHT.
LOOK FOR MVFR AND POSSIBLY EVEN IFR CONDITIONS HEADING INTO
THURSDAY NIGHT.
OUTLOOK...
FRIDAY - SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA...SHSN.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A SOAKING RAINFALL IS EXPECTED MAINLY THURSDAY AFTERNOON THROUGH
THURSDAY NIGHT. WE DID NOT ASSIGN A "WET FLAG" TO OUR NFDRS
SINCE THE BULK OF THE RAIN WILL NOT FALL UNTIL AFTER 100 PM
THURSDAY.
RAINFALL AMOUNTS SHOULD BE A QUARTER INCH OR MORE EVERYWHERE.
IT DRIES OUT FRIDAY WITH A NORTHWEST WIND 5- 15 MPH.
ANOTHER CLIPPER TYPE SYSTEM COULD BRING RAIN OR SNOW SHOWERS
SATURDAY NIGHT...ESPECIALLY NORTH AND WEST OF ALBANY. THERE
MIGHT BE SOME MINOR ACCUMULATIONS OF SNOW.
MUCH COLDER AIR WORKS IN ON GUSTY WINDS FOR THE LATER PORTION OF THE
WEEKEND.
&&
.HYDROLOGY...
A COLD FRONT WILL BRING A ROUND OF RAIN SHOWERS TO THE REGION
LATER THURSDAY INTO THURSDAY NIGHT.
THIS IS A PROGRESSIVE SYSTEM...SO IT WILL NOT LINGER TOO LONG.
IT DRIES OUT BY FRIDAY.
RAINFALL AMOUNTS LOOK TO BE HALF AN INCH TO AROUND AN INCH IN
THE VALLEYS...POSSIBLY UP TO TWO INCHES ACROSS THE HIGHER TERRAIN...
OF THE SOUTHERN GREENS AND BERKSHIRES.
THIS RAIN WILL PRODUCE WITHIN BANK RISES...MAYBE A FEW SPOTS
APPROACHING ACTION STAGE. NO FLOODING EXPECTED.
COOLER AND DRIER WEATHER WILL RETURN FRIDAY INTO THE FIRST HALF
OF THE WEEKEND. ANOTHER SYSTEM MAY BRING LIGHT PCPN IN THE FORM OF
RAIN/SNOW SHOWERS SATURDAY NIGHT INTO SUNDAY WITH LITTLE OR NO HYDROLOGICAL
IMPACTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/GJM
NEAR TERM...HWJIV/NAS
SHORT TERM...HWJIV/KL
LONG TERM...WASULA
AVIATION...KL
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV/KL/WASULA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
333 AM EST THU NOV 19 2015
.DISCUSSION...
...INCREASED RAIN CHANCES THRU TONIGHT WITH SLIGHT CHANCE OF
LIGHTNING STORMS...
TODAY-TONIGHT...COOL FRONT IN THE FLORIDA PANHANDLE WILL MOVE SLOWLY
EAST IN TANDEM WITH SLOWLY RETREATING DEEP LAYER RIDGE JUST OFF THE
EASTERN SEABOARD. ANOMALOUSLY MOIST AIR MASS AHEAD OF THE FRONT
AND SOME DIVERGENCE ALOFT SHOULD PROVIDE FOR HIGH POPS EVEN THOUGH
THE LOW LEVEL CONVERGENCE WILL BE WEAKENING.
LATEST SATELLITE SHOWS THAT MULTI-LAYERED CLOUD BAND CLOSE TO THE
FRONT WILL HOLD BACK ENOUGH FOR MODEST SURFACE HEATING THIS MORNING
ACROSS THE LOCAL AREA. THIS HEATING SHOULD ALLOW FOR AN EAST COAST
SEA BREEZE WHICH WILL ACT AS THE INITIAL FOCUS FOR SCATTERED SHOWERS
AND ISOLATED LIGHTNING STORMS BY EARLY-MID AFTERNOON. THEN AS
WEAK PRE FRONTAL CONVERGENCE SLIDES INTO THE AREA...CONVECTION
SHOULD INCREASE INTO EARLY EVENING. MOS POPS ARE REALLY HIGH AT
60-80 PERCENT TODAY AND 60-90 PERCENT TONIGHT. THINK THAT THE BULK
OF THIS WILL BE IN THE MID-LATE AFTERNOON AND EVENING. DECIDED TO
JUST STICK WITH THE PREVIOUS POPS WHICH ARE 60-70 PERCENT
TODAY/TONIGHT. RAINFALL AMOUNTS EXPECTED TO AVERAGE A QUARTER TO
HALF INCH...BUT A FEW STORMS COULD DUMP A QUICK ONE OR TWO INCHES.
FRI...SURFACE BOUNDARY EXPECTED TO BECOME QUASI-STATIONARY OVER
SOUTHERN FLORIDA DURING THE DAY WITH SOME MID-LEVEL DRY AIR
FILTERING IN OVERHEAD. BEST MOISTURE WILL EXIST ACROSS THE SOUTHERN
THIRD OF THE CWA...THUS HIGHEST POPS RESIDE OVER THIS AREA. GIVEN THE
BOUNDARY`S LACK OF FORWARD MOMENTUM BY THIS TIME...AND ITS WEST-EAST
ORIENTATION...COOL AND DRY AIR ADVECTION LOOKS TO BE UNIMPRESSIVE
DURING THE DAY...ESPECIALLY CONSIDERING WINDS ARE EXPECTED TO VEER
ONSHORE THROUGH THE DAY.
WEEKEND...EXPECTING A RESURGENCE OF MOISTURE ACROSS THE CENTRAL
AND SOUTHERN HALF OF THE PENINSULA AS WEAK LOW PRESSURE TRIES TO
ORGANIZE ALONG THE TAIL END OF THE FRONT OVER THE EASTERN GULF.
GUIDANCE...EACH WITH THEIR VARYING DEGREES OF DEVELOPMENT...INCREASE
MOISTURE AND RAIN CHANCES DURING THE DAY ON SATURDAY AND EVEN INTO
SUNDAY IF YOU WERE TO BELIEVE THE ECMWF. THIS FORECAST CYCLE WILL
AIM FOR A COMPROMISE AMONGST THE GLOBAL MODELS...ULTIMATELY KEEPING
RAIN CHANCES AROUND THROUGH SUNDAY BEFORE A REINFORCING FRONT STARTS
TO DRY THINGS OUT LATE SUNDAY OR EARLY MONDAY.
EARLY NEXT WEEK...GIVEN THE VARIOUS MODEL DISCREPANCIES LATE IN THE
WEEKEND INTO MONDAY...CONFIDENCE IS LOW ON THE EXACT TIMING OF THE
REINFORCING SHOT OF COOL CONTINENTAL AIR FROM THE NORTH. REGARDLESS
OF THE TIMING...DRY AIR ADVECTION AND COOLING WILL BE MORE IMPRESSIVE
BEHIND THIS SECOND BOUNDARY. FOR AREAS CLOSE TO THE
COAST...MODIFICATION OFF THE ATLANTIC WILL BE QUICK TO OCCUR AS
WINDS VEER ONSHORE.
&&
.AVIATION...
SCATTERED SHOWERS HAVE BEEN RUNNING UP THE TREASURE AND
SPACE COASTS OVERNIGHT AND PRODUCING BRIEF DOWNPOURS WITH IFR
CONDITIONS. THIS IS A SIGN OF WHAT IS AHEAD THIS AFTERNOON AS THE
VERY MOIST AIR MASS UNDERGOES DESTABILIZATION AND WEAK PRE FRONTAL
CONVERGENCE ENTERS THE MIX. THE HRRR MODEL HAS BEEN HOLDING OFF
DAYTIME CONVECTIVE INITIATION UNTIL EARLY AFTERNOON. WOULD EXPECT
COVERAGE TO THEN INCREASE THROUGH EARLY EVENING. WITH THE VERY
MOIST AIR MASS...MOST SHOWERS WILL PRODUCE BRIEF IFR. ISOLATED
STORMS COULD HAVE IFR-MVFR FOR AN HOUR OR MORE.
&&
.MARINE...
TODAY-TONIGHT...LATEST WINDS AT BUOY 41009 WERE STILL AROUND 20
KNOTS WITH SEAS NEAR 8 FEET. ALL GUIDANCE WEAKENS THE PRESSURE
GRADIENT STEADILY DURING THE DAY. STILL...WILL NEED TO HOLD ONTO
AN ADVISORY EARLY THIS MORNING OFFSHORE...WITH EXERCISE CAUTION
STATEMENT NEAR SHORE. BY AFTERNOON SOUTHERLY WINDS WILL DROP OFF
TO 10-15 KNOTS AS SEAS DIMINISH TO 5-6 FEET. SCATTERED SHOWERS AND
ISOLATED STORMS SHOULD START TO MOVE OFFSHORE BY MID-LATE AFTERNOON.
WITH SLOW MOVING FRONTAL BOUNDARY DROPPING THROUGH THE NORTHERN
WATERS TONIGHT...THE SHOWERS/ISOLATED STORMS ARE EXPECTED TO
PERSIST MUCH OF THE NIGHT.
FRI...SURFACE BOUNDARY WILL MOVE THROUGH THE COASTAL WATERS
THROUGH THE MORNING HOURS ON FRIDAY BEFORE STALLING OVER SOUTH
FLORIDA. SURFACE WINDS WILL RESPOND BY VEERING FROM A LIGHT
TO GENTLE W/NW BREEZE EARLY FRI MORNING...TO A GENTLE TO MODERATE
NORTHERLY BREEZE BY MIDDAY...THEN A MODERATE E/NE BREEZE AFTER
SUNSET.
SAT-TUE...PRESSURE GRADIENT RELAXES DURING ON SATURDAY WITH A GENTLE
EAST/SOUTHEAST BREEZE EXPECTED. WIND FORECAST REMAINS A BIT TRICKY
SATURDAY NIGHT INTO SUNDAY AS WEAK LOW PRESSURE TRIES TO ORGANIZE
OVER THE GULF BEFORE MOVING EAST OVER THE PENINSULA. ONCE THE LOW
PRESSURE MOVES EAST OF THE STATE..LATE SUNDAY OR EARLY MONDAY...SEAS
AND NORTHERLY WINDS WILL BUILD QUICKLY BEHIND A REINFORCING FRONT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 84 68 78 69 / 70 60 20 30
MCO 85 69 80 68 / 70 60 20 20
MLB 85 72 81 72 / 60 70 30 30
VRB 85 71 81 72 / 60 70 40 30
LEE 84 67 79 66 / 70 60 20 20
SFB 84 69 79 68 / 70 60 20 20
ORL 85 70 80 69 / 70 60 20 20
FPR 85 71 81 71 / 60 70 40 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR
FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 20-60 NM-
SEBASTIAN INLET TO JUPITER INLET 20-60 NM-VOLUSIA-BREVARD
COUNTY LINE TO SEBASTIAN INLET 20-60 NM.
&&
$$
SHORT TERM...LASCODY
LONG TERM....ULRICH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
207 AM MST THU NOV 19 2015
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 206 AM MST THU NOV 19 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOWS LONG FETCH OF NW
FLOW EXTENDING FROM THE PACIFIC NW ACROSS THE CENTRAL ROCKIES INTO
THE THE PLAINS...WITH SARGE TROUGH ALONG THE MISSISSIPPI RIVER
VALLEY. AT THE SURFACE HIGH PRESSURE IS IN PLACE.
SNOW PACK CONTINUES TO BE A CONSIDERATION THROUGH AT LEAST THE SHORT
RANGE PERIODS FOR T/TD...AND ADJUSTMENTS WERE MADE ACCORDINGLY.
TODAY-TONIGHT...PASSING HIGH CLOUDS ASSOCIATED WITH WEAK RIPPLES
WITHIN NW FLOW ALOFT WILL CONTINUE THROUGH TONIGHT. OTHERWISE DRY
CONDITIONS WILL PERSIST. A COOLER AIR MASS WILL REMAIN IN PLACE
AND TEMPERATURES WILL BE AT LEAST 5-15F COOLER THAN YESTERDAY
ESPECIALLY IF WE SEE MORE EXTENSIVE/OPAQUE CLOUD COVER.
FRIDAY-FRIDAY NIGHT...A STRONGER SHORTWAVE TROUGH/CLIPPER EMBEDDED
WITH NW FLOW WILL MOVE THROUGH THE REGION ALONG WITH ANOTHER COLD
FRONT (PASSING LATE AFTERNOON). MOISTURE ADVECTION IS LIMITED DUE TO
THE TRAJECTORY/TRACK OF THIS SYSTEM...HOWEVER THERE WILL BE ENOUGH
FORCING TO SUPPORT A FEW RAIN/SNOW SHOWERS OR SPRINKLES/FLURRIES
DURING THESE PERIODS. MODELS SHOWS VERY STRONG GRADIENT
ALONG/BEHIND FRONT HIGHLIGHTED BY 8-10 MB 3HR PRESSURE RISES (10-15
MB 6 HR PRESSURE RISES). ITS HARD TO TELL HOW DEEP WE WILL MIX AS
THERE COULD BE EXTENSIVE CLOUD COVER AND POSSIBLE INVERSION ABOVE
LINGERING SNOW PACK. IF WE WERE TO MIX TO 850 MB WE COULD SEE WINDS
45-50 MPH. WINDS ABOVE THIS LAYER ARE EVEN HIGHER...SO THIS WILL
NEED TO BE WATCHED IN THE EVENT SHOWERS HELP MIXING AND CREATE
ISOLATED 60 MPH DOWNBURST. INCREASING WAA AHEAD OF THIS FRONT
SHOULD ALLOW SOME LOCATIONS TO WARM INTO THE MID 50S BEFORE
TEMPERATURES START DECREASING IN THE AFTERNOON.
SATURDAY-SATURDAY NIGHT...ANOTHER SHORTWAVE TROUGH IS ADVERTISED TO
PASS THROUGH THE NORTHERN PLAINS...HOWEVER THIS FEATURE IS NOT QUITE
AS STRONG...AND MOISTURE PROFILES ARE EVEN LESS FAVORABLE. DRY
CONDITIONS SHOULD BE EXPECTED THOUGH THESE PERIODS. THIS SHORTWAVE
WILL ALSO HELP REINFORCE THE COOLER POST FRONT AIR MASS...SO HIGHS
IN THE 30S ARE EXPECTED ACROSS OUR CWA AND I COULD SEE SOME
LOCATIONS WITH HIGHS AROUND 32.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 206 AM MST THU NOV 19 2015
NORTHWEST FLOW ALOFT REMAINS OVER THE REGION ON SUNDAY BEFORE AN
UPPER RIDGE OVER THE WESTERN CONUS FLATTENS OUT OVER THE HIGH PLAINS
ON MONDAY AND TUESDAY. THIS PATTERN WILL BRING DRY CONDITIONS AND
WARMER TEMPERATURES TO THE FORECAST THROUGH EARLY NEXT WEEK.
GUIDANCE IS SHOWING AN UPPER LOW MOVING OVER THE PACIFIC NORTHWEST
TUESDAY NIGHT. DRY CONDITIONS CONTINUE FOR THE AREA ON WEDNESDAY
AHEAD OF THIS SYSTEM AS IT TRAVELS EASTWARD TOWARDS THE PLAINS WITH
THE ASSOCIATED COLD FRONT LOOKING TO PASS THROUGH THE REGION BY
THURSDAY. COULD SEE PRECIP CHANCES LATER NEXT WEEK WITH THIS SYSTEM.
EXPECT TEMPERATURES TO WARM INTO EARLY NEXT WEEK WITH HIGHS IN THE
40S ON SUNDAY GRADUALLY INCREASING INTO THE 50S BY TUESDAY BEFORE
COOLING INTO THE UPPER 40S TO MID 50S FOR WEDNESDAY. CONTINUED TO
KEEP THE COOLER TEMPERATURES IN AREAS WHERE SNOWPACK MAY STILL BE
PRESENT. HOWEVER...SUSPECT MELTING WILL OCCUR BEFORE THE END OF THIS
PERIOD. LOWS WILL GENERALLY BE IN THE 20S. THE REGION COULD SEE A
BLAST OF COLD AIR TOWARDS THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1028 PM MST WED NOV 18 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. WEST TO NORTHWEST
WINDS OF 5 TO NEAR 10 KNOTS SLOWLY SHIFT TO THE SOUTH THROUGH THE
PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1201 AM EST THU NOV 19 2015
.UPDATE...
ISSUED AT 1000 PM EST WED NOV 18 2015
BAND OF RAIN SHOWERS HAS COMPLETELY MOVED OUT OF THE AREA AND THE
FORECAST HAS BEEN UPDATED ACCORDINGLY. WIND STILL GUSTING 20 TO 30
MPH OUT OF THE SSW. NEXT BATCH OF RAIN SHOWERS ARRIVES LATE
TONIGHT...BUT MAINLY INTO TOMORROW MORNING ASSOCIATED WITH NEXT
SHORTWAVE AND SFC TROUGH/COLD FRONT AND DEEPER MOISTURE. LOW LEVEL
TEMPERATURES WILL STILL NOT BE COLD ENOUGH FOR ANY SNOW (H8 TEMPS
-1C TO +1C). THE COLDER AIR PLOWS THROUGH THE REGION VIA
INCREASING VERY GUSTY SW/WSW WINDS THROUGH LATTER MORNING AND
AFTERNOON...FOR WHICH WE WILL START TO SEE CHANGEOVERS TO SNOW
WITH LITTLE TO NO ACCUMULATION. GUSTS IN THE AFTERNOON 35-45 MPH
IN MANY LOCALES...HIGHEST IMMEDIATELY DOWNWIND OF LAKE MICHIGAN
(NW LOWER COAST AND MACKINAC COUNTY OF EASTERN UPPER).
&&
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 323 PM EST WED NOV 18 2015
OCCLUDED SURFACE LOW CENTER HAS REACHED NRN MINNESOTA LATE THIS
AFTERNOON...WITH THE ASSOCIATED COLD FRONT EXTENDING SOUTHWARD THRU
CENTRAL WISCONSIN AND CENTRAL ILLINOIS INTO THE LOWER MISSISSIPPI
VALLEY. WARM/MOIST AIR CONTINUES TO STREAM NORTHWARD OUT OF THE GULF
ALONG AND AHEAD OF THE COLD FRONT...AND INTO MICHIGAN. SFC DWPTS ARE
NOW MAINLY IN THE UPPER 40S ACROSS OUR ENTIRE CWA... WITH ALL LOCAL
OBS REPORTING AT LEAST A PERIOD OF RAIN DURING THE AFTERNOON.
NEXT WAVE OF WIDESPREAD RAIN IS MOVING THRU SRN LWR MICHIGAN TOWARD
OUR CWA...TARGETING THE ERN HALF FOR HIGHEST POPS FOR THE REST OF
THE AFTERNOON INTO THIS EVENING. NAM12...RAP13 AND HRRR ALL SUGGEST
THIS SCENARIO WITH SLIGHT VARIATIONS...AND OVERALL MODEL TRENDS HAVE
BEEN DOWNWARD FOR EXPECTED POPS LATE THIS AFTERNOON THRU TONIGHT. IN
FACT...ALL OF THE ABOVE MODELS NEARLY DISSIPATE THE AREA OF SHOWERS
CURRENTLY DEVELOPING OVER WISCONSIN BEFORE IT CAN REACH MICHIGAN
TONIGHT...HOLDING OFF ON THE REDEVELOPMENT OF BETTER POPS UNTIL
AFTER 12Z THURSDAY. HAVE DIMINISHED POPS FOR TONIGHT...BUT STILL
TARGET ERN SECTIONS OF OUR CWA FOR BEST CHANCE OF RAIN. LOW LEVELS
DO BEGIN TO COOL IN THE WAKE OF THE COLD FRONT TONIGHT...BUT
SUFFICIENTLY COLD AIR TO RESULT IN MIXED PRECIP AND/OR SNOW WILL
HOLD OFF UNTIL TOMORROW. THUS...ALL PRECIP WILL REMAIN LIQUID THRU
THE NIGHT...WITH OVERNIGHT LOWS FALLING INTO THE LOWER 40S.
STRONGEST CORRIDOR OF LOW LEVEL WINDS HAS REACHED OUR CWA...AND SO
FAR HAVE REMAINED JUST BELOW WIND ADVISORY CRITERIA. HAVE SEEN
NOTHING UPSTREAM OVER WISCONSIN TO INDICATE ANY FURTHER
STRENGTHENING OF WIND SPEEDS...AND WE MAY EVEN SEE A SLIGHT DIMINISH
LATER THIS EVENING AND OVERNIGHT. SO...AT THIS POINT...NO WIND
ADVISORY WILL BE NEEDED...BUT WILL CONTINUE TO KEEP A CLOSE EYE ON
LOCAL SURFACE OBS.
&&
.SHORT TERM...(THURSDAY THROUGH SATURDAY)
ISSUED AT 323 PM EST WED NOV 18 2015
HIGH IMPACT WEATHER POTENTIAL: LINGERING WIND CONCERNS THURSDAY.
ADDRESSING POTENTIAL WIDESPREAD SNOW EVENT SATURDAY.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: DEEP TROUGH DIGGING THROUGH
THE CENTRAL PART OF THE COUNTRY...LED IN CHARGE BY OPENING SOUTHERN
STREAM WAVE PIVOTING ACROSS WISCONSIN. FAR UPSTREAM PACIFIC FLOW
REGIME A TOUCH MORE "FLATISH" IN APPEARANCE...WITH ROBUST UPPER JET
CORE PUNCHING THROUGH THE NORTHWEST STATES. PATTERN SET TO GO
THROUGH SOME CHANGES IN THE COMING DAYS...WITH STRONG SECONDARY JET
MAX ACROSS THE NORTH PACIFIC FORCING AMPLIFYING AND TRANSIENT
RIDGING ACROSS THE NORTHEAST PACIFIC. SUBTLE WAVE DIVING DOWN THE
FRONT SIDE OF THIS RIDGE AMPLIFICATION...ALONG WITH THE POTENTIAL
STRENGTHENING OF UPPER JET CORE ALONG RIDGE/TROUGH INTERFACE...COULD
WORK IN TANDEM TO DRUM UP A RATHER SIGNIFICANT SNOW EVENT FOR AT
LEAST SOME ACROSS THE GREAT LAKES HEADING INTO THIS WEEKEND.
OTHERWISE...A MUCH MORE NOVEMBER FEEL EXPECTED THURSDAY INTO THE
WEEKEND...AS TROUGHING AND MODIFIED POLAR AIR DOMINATES.
PRIMARY FORECAST CONCERNS/CHALLENGES: INITIAL CONCERNS CENTERED ON
WIND GUSTS AND LAKE INDUCED SNOW SHOWER POTENTIAL THURSDAY AND
FRIDAY. ATTENTION DIRECTED TO POSSIBLE WINTER STORM IMPACTS HEADING
INTO AND THROUGH SATURDAY.
DETAILS: MAIN SYSTEM CONTINUES TO LIFT WELL NORTH OF THE AREA
TONIGHT AND THURSDAY...DRAGGING MAIN COLD FRONT ACROSS NORTHERN
MICHIGAN THURSDAY MORNING. ATTENDANT CAA AND REMNANT TIGHT PRESSURE
GRADIENT WILL WORK IN TANDEM TO CONTINUE THE GUSTY WINDS...ALTHOUGH
WIND DIRECTION WILL TURN DECIDEDLY MORE SOUTHWEST AFTER FRONTAL
PASSAGE. WINDS LOOK TO BE SUSTAINED AT 15 TO 25 MPH...WITH BUFKIT
MOMENTUM TRANSFER EASILY SUPPORTING WIDESPREAD WIND GUSTS A GOOD 10
OR SO MILES PER HOUR STRONGER...WITH GUSTS PUSHING 40 MPH AT TIMES
ALONG THE EXPOSED LAKE MICHIGAN COAST. BAND OF RAIN/SNOW SHOWERS TO
ACCOMPANY PASSING COLD FRONT...WITH PRECIP COVERAGE NO DOUBT
AUGMENTED BY INCREASING LAKE PROCESSES. COLD AIR WILL ONLY DEEPENING
WITH TIME...WITH AMPLE AIR/WATER TEMPERATURE DIFFERENCE TO CONTINUE
LAKE INDUCED SNOW SHOWERS IN FAVORED WSW-SW FLOW AREAS (TIP OF THE
MITT AND STRAITS). DEEPEST MOISTURE AND BEST SYNOPTIC FORCING
CONTINUES TO REMAIN NORTH OF OUR AREA...AND SAID WIND DIRECTION
MEANS NO MULTI-LAKE CONNECTION. SOUNDINGS SHOW DOWN LOW INVERTED-V
SIGNATURE...INDICATIVE OF UPSTREAM LOWER LEVEL DRY AIR AND NO LAKE
SUPERIOR PRECONDITIONING. SO...DESPITE MORE THAN FAVORABLE DELTA T/S
IN THE HIGH TEENS...JUST NOT SEEING A WHOLE LOT OF POTENTIAL FOR ANY
SIGNIFICANT SNOW ACCUMULATION (NOT MUCH MORE THAN AN INCH).
ABOVE TRENDS CONTINUE THURSDAY NIGHT AND FRIDAY...ALTHOUGH WINDS
GRADUALLY WEAKEN AND SLOWLY VEER WITH TIME. LIMITED MOISTURE
CONTINUES...WITH NO MULTI-LAKE CONNECTION EVER ESTABLISHED.
SO...MOSTLY LIGHT LAKE SNOWS WILL CONTINUE...FOCUSED ACROSS THE TIP
OF THE MITT WHERE ANOTHER INCH OR SO IS EXPECTED BY LATER FRIDAY.
MUCH...MUCH COLDER BY FRIDAY...ALTHOUGH HIGHS IN THE MID 30S/AROUND
40 ABOUT ON PAR FOR THIS TIME OF YEAR.
ATTENTION FRIDAY NIGHT AND SATURDAY DIRECTED AT THAT POTENTIAL SNOW
PRODUCING SYSTEM TALKED ABOUT IN THE OPENING PARAGRAPH. WOULD LOVE
TO OFFER MORE CONCRETE ANSWERS...BUT THERE IS SIMPLY TOO MUCH
UNCERTAINTY TO GO WITH MUCH SPECIFICS JUST YET. UPPER JET CORE AND
SUBTLE WAVE WILL NOT BE FULLY SAMPLED UNTIL TOMORROW...AND EVEN THEN
WOULD NOT BE SURPRISED TO SEE GUIDANCE FLUCTUATIONS GIVEN COMPLEXITY
OF MID AND UPPER LEVEL FEATURES AND THEIR INTERACTION. AS OF
NOW...FULL RANGE OF POSSIBILITIES REMAIN VIABLE...FROM A MUCH
FLATTER AND WEAKER SOLUTION REMAINING WELL TO OUR SOUTH...TO A MORE
FULLY ORGANIZED AND DEEP LAYER STORM BRINGING SIGNIFICANT SNOW
ACCUMULATIONS AND IMPACTS TO MUCH...IF NOT ALL...OF NORTHERN
MICHIGAN. AS IS OFTEN THE CASE...REALITY WILL PROBABLY LIE SOMEWHERE
BETWEEN THIS TWO EXTREMES...WHICH WOULD STILL LIKELY DRIVE SOME
ACCUMULATING SNOW TO AT LEAST PARTS OF NORTHERN LOWER MICHIGAN. NO
DOUBT SYSTEM WILL HAVE TO BE CLOSELY MONITORED...WITH THE MORE
WRAPPED UP SCENARIO (E.G. 00Z ECMWF) SHOWING EXCELLENT LIFT IN THE
DGZ...ENHANCED BANDING POTENTIAL VIA FGEN RESPONSE...AND HINTS OF
SOME REDUCED STABILITY ALOFT. WILL BEGIN TO RAMP UP THIS STORM
POTENTIAL IN OUR LATEST HAZARDOUS WEATHER PRODUCTS AND THROUGH OUR
WEB GRAPHICS. DEFINITELY WORTH MONITORING IN THE COMING DAYS FOR
SURE.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 323 PM EST WED NOV 18 2015
DEPENDING ON HOW SATURDAY`S SYSTEM EVOLVES...COULD STILL BE DEALING
WITH AT LEAST LIGHT SYNOPTIC SNOW ACROSS THE SOUTHEASTERN COUNTIES
TO BEGIN THE PERIOD. HOWEVER...AS THE LOW DEPARTS QUICKLY OFF TO THE
NORTH AND EAST...WINDS SHIFT NORTHERLY SATURDAY NIGHT AND EVENTUALLY
WNW BY SUNDAY MORNING. WITH H8 TEMPS PROGGED TO BE ROUGHLY -13C
ACROSS NRN MI AND DELTA TS ~22C...WOULD EXPECT LES TO KICK IN AND
BRIEFLY TARGET AREAS WEST OF THE 131 CORRIDOR INCLUDING THE TRAVERSE
CITY AND CADILLAC AREAS ALONG WITH NRN CHIPPEWA COUNTY BEFORE
SHIFTING TO MORE WNW FLOW FAVORED LOCATIONS OF NORTHWEST LOWER AND
NRN CHIPPEWA BY EARLY SUNDAY MORNING. SUNDAY EVENING...LLEVEL WINDS
SHIFT WESTERLY...THEN WSW SUNDAY NIGHT AIDING IN WARMING H8 TEMPS
AND AN EVENTUAL SHUT OFF TO THE MAJORITY OF LAKE INDUCED SNOW.
HINTS ARE THERE MONDAY THAT ANOTHER WEAK WAVE MAY SLIDE THROUGH
RATHER ZONAL UPPER LEVEL FLOW TIED TO AN ASSOCIATED NRN JET STREAK
ACROSS THE NORTHERN HALF OF THE CWA...PERHAPS PROVIDING ADDITIONAL
SNOW SHOWER CHANCES. GLOBAL GUIDANCE BEGINS TO LARGELY DIVERGE BY
WEDNESDAY WITH SEVERAL SOLUTIONS POSSIBLE...ALTHOUGH ANOTHER WARM UP
LOOKS TO BE ON TAP FOR THE MIDDLE OF NEXT WEEK INTO PERHAPS THE
THANKSGIVING HOLIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1152 PM EST WED NOV 18 2015
...STRONG WINDS AND SHOWERY...
STRONG LOW PRESSURE LIFTS UP THROUGH NW ONTARIO OVER THE NEXT 24
HOURS. A FRONTAL BOUNDARY HAS PUSHED THROUGH NRN MICHIGAN AND A
LOOSER PRESSURE GRADIENT AND DRIER SWATH OF AIR WERE MOVING IN
OVER NRN MICHIGAN. WINDS REMAINED GUSTY HOWEVER...AT 20 TO 30 MPH
AND A PERIOD OF PARTIAL CLEARING WAS MOVING IN. THE NEXT SFC
TROUGH/COLD FRONT WAS PRESSING QUICKLY EAST...AND WILL ARRIVE
AROUND/SHORTLY AFTER DAYBREAK. OVERLAKE INSTABILITY WILL DEVELOP
MVFR CIGS AGAIN BY DAWN OVER THE NW LOWER AIRPORTS...WHILE SKIES
LIKELY REMAIN PARTLY CLOUDY INTO MID MORNING AT APN. THE PRESSURE
GRADIENT TIGHTENS AGAIN THROUGH THE DAY AND EVENING...WITH WINDS
SHIFTING MORE SW/WSW AT REACHING GUSTS IN THE AFTERNOON UP TO 40
TO 45 MPH. THE COLD FRONT WILL BRING PERIODIC LIGHT RAIN SHOWERS
TO PRIMARILY PLN...WHICH WILL CHANGE OVER TO SNOW AND REDUCED
VSBYS LATER IN THE AFTERNOON AND EVENING. MAYBE A HALF OF AN INCH
THURSDAY EVENING.
&&
.MARINE...
ISSUED AT 323 PM EST WED NOV 18 2015
GALE FORCE WINDS AND HIGH WAVES WILL CONTINUE TO IMPACT ALL
NEARSHORE AREAS THRU TONIGHT (AT LEAST) AND AS DEEP LOW PRESSURE
LIFTS NE INTO S CENTRAL CANADA...PRODUCING A TIGHT LOW LEVEL
PRESSURE GRADIENT ACROSS THE WRN GREAT LAKES REGION. WAVES OF
WIDESPREAD RAIN WILL ALSO CONTINUE TO IMPACT OUR AREA THRU
TONIGHT...BECOMING MIX WITH SNOW ON THURSDAY.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...GALE WARNING UNTIL 5 AM EST THURSDAY FOR LHZ346>349.
GALE WARNING UNTIL 7 AM EST FRIDAY FOR LHZ345.
LM...GALE WARNING UNTIL 7 AM EST FRIDAY FOR LMZ323-341-342-344>346.
LS...GALE WARNING UNTIL 5 AM EST THURSDAY FOR LSZ322.
GALE WARNING UNTIL 7 AM EST FRIDAY FOR LSZ321.
&&
$$
UPDATE...DICKSON
NEAR TERM...MLR
SHORT TERM...MSB
LONG TERM...GILLEN
AVIATION...DICKSON
MARINE...MLR
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
926 PM MST WED NOV 18 2015
.UPDATE...
A COUPLE MORE UPDATES THIS EVENING. PERSISTENT SNOW BAND OVER
SOUTHERN BIG HORN AND SHERIDAN COUNTIES HAS STRENGTHENED IN THE
PAST HOUR AND LAW ENFORCEMENT REPORTS HALF AN INCH TO AN INCH OF
ACCUMULATION IN SOME AREAS. MODELS NOT HANDLING THIS FEATURE WELL
AT ALL BUT HRRR HAS SOME HINT OF IT AND KEEPS IT IN PLACE UNTIL
MIDNIGHT. ADJUSTED FORECAST POPS UP TO LIKELY AND ADDED AN INCH OF
ADDITIONAL ACCUMULATION TO ACCOUNT FOR POSSIBLY 3 HOURS OF
SNOWFALL. ROADS ARE REPORTEDLY GETTING PRETTY SLICK IN SHERIDAN
INCLUDING I-90 SO ANYONE TRAVELING THAT DIRECTION BE PREPARED FOR
DIFFICULT TRAVEL CONDITIONS.
THAT SNOWBAND APPEARS TO BE THE ONLY TRAVEL CONCERN FOR THE AREA
WITH THE REST OF THE SNOW BANDS WEAKENING IN GENERAL. WINDS
CONTINUE A DOWNWARD TREND TOO AND AS A RESULT TEMPERATURES ARE
REALLY DROPPING ACROSS THE AREA. ALREADY NEAR FORECAST LOWS IN
MANY AREAS SO LOWERED TEMPERATURES 5 TO 8 DEGREES. THIS PUTS MOST
OF THE AREA IN THE TEENS FOR TOMORROW MORNING. CHAMBERS
&&
.SHORT TERM...VALID FOR THU AND FRI...
STRONG UPPER LEVEL DISTURBANCE WAS SEEN DEPARTING TO SOUTHEAST
EARLY THIS MORNING. IN ITS WAKE STRONG WINDS MOVED INTO THE
FORECAST AREA. THE STRONGEST WINDS HAVE MOVED OUT TO EASTERN ZONES
AS OF THIS UPDATE SO NEARLY ALL HIGH WIND WARNINGS HAVE BEEN
CANCELLED EXCEPT FOR WARNINGS IN SHERIDAN...ROSEBUD...SOUTHERN BIG
HORN...CUSTER...CARTER...FALLON...AND POWDER RIVER COUNTIES.
STRONG WINDS IN THESE LOCATIONS SHOULD BEGIN DIMINISHING JUST
AFTER SUNSET AS THE STRONG JET MOVES EAST AND BOUNDARY LAYER
COOLING MAKES IT HARDER FOR STRONG WINDS TO REACH THE
SURFACE...THOUGH CARTER AND FALLON COUNTIES COULD SEE WARNING
CRITERIA WINDS PERSIST UNTIL SUNRISE THURSDAY. EVEN THOUGH WINDS
WILL LESSEN THROUGH THE NIGHT WE STILL EXPECT ELEVATED WINDS UNTIL
SUNRISE AND URGE THAT FOLKS STILL TAKE WIND PRECAUTIONS THROUGH
THURSDAY MORNING.
NORTHWEST FLOW ALOFT TAKES OVER THURSDAY MORNING. A SHORTWAVE
TROUGH FURTHER UPSTREAM WILL QUICKLY AMPLIFY AND DIVE SOUTHEAST
THURSDAY AFTERNOON. WEAK COLD FRONT WILL TURN WINDS NORTHERLY
THURSDAY NIGHT AND ANOTHER ROUND OF COLD AIR ADVECTION...COMBINED
WITH INCREASING MOISTURE ALOFT...WILL ALLOW A QUICK SHOT OF SNOW
FOR MOST OF SOUTHERN MONTANA ON FRIDAY...MOSTLY IN THE MORNING.
WITH A VERY FAST MOVING SYSTEM, AND NOT THE MOST IDEAL
DYNAMICS...I AM NOT EXPECTING HIGH IMPACT ACCUMULATIONS WITH THIS
SYSTEM AT THIS TIME. THERE IS STILL A BIT OF UNCERTAINTY IN THE
PLACEMENT OF THE HIGHEST QPF. ALSO SHOULD NOTE THERE HAS BEEN A
POSITIVE TREND IN PRECIPITATION AMOUNTS OVER SOUTHERN PORTIONS OF
THE FORECAST AREA SO USERS SHOULD BE SURE TO STAY UP TO DATE WITH
OUR FORECAST IN CASE OUR THINKING CHANGES OVER THE NEXT 36 HOURS.
CONDITIONS CLEAR OUT FRIDAY AFTERNOON BUT COOL POST FRONTAL
TEMPERATURES AND CLEAR SKIES WILL ALLOW MOST LOCATIONS TO SEE
THEIR COLDEST TEMPERATURE OF THE SEASON SATURDAY MORNING.
TEMPERATURES WILL REMAIN COOL WITH LOWS IN THE MID TO LOW 20S IN
CENTRAL MONTANA AND IN THE MID TO LOW TEENS OUT EAST AND NEAR
SHERIDAN. DOBBS
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
FOLLOWING THE CLIPPER SYSTEM THURSDAY INTO FRIDAY...THE WEEKEND
SHOULD BE QUIET. THE FLOW WILL BE COME NORTHWESTERLY WITH A RIDGE
DEVELOPING OFF THE COAST OF BRITISH COLUMBIA. THE FLOW WILL
REMAIN GENERALLY NORTHWESTERLY INTO EARLY NEXT WEEK. MONDAY A
TROUGH STARTS TO DEVELOP IN ALASKA AND GOING INTO TUESDAY...WILL
DEVELOP INTO A DEEPENING TROUGH OVER THE WESTERN US. MODELS ARE
COMING INTO BETTER AGREEMENT WITH THIS WAVE...HOWEVER HAVE SHIFTED
AWAY FROM A CLOSED LOW. GFS ENSEMBLE SHOWS REMARKABLE CONSISTENCE
OVER THE WESTERN US EVEN INTO THE MIDDLE OF NEXT WEEK. THE ONE
ISSUE IS THAT MODELS UPSTREAM HAVE MUCH GREATER SPREAD. FOR NOW
HAVE JUST TRENDED TOWARDS LOWER TEMPERATURES AND HAVE KEPT CHANCE
POPS TUESDAY AND WEDNESDAY. REIMER
&&
.AVIATION...
WINDS SHOULD CONTINUE TO DECREASE OVERNIGHT. FLIGHT CONDITIONS
SHOULD REMAIN VFR...ALTHOUGH ISOLD SNOW SHOWERS MAY BRING
LOCALIZED MVFR VISIBILITIES. EXPECT GUSTY WINDS TO RETURN TO THE
LIVINGSTON AREA ON THURSDAY MORNING...WITH GUSTS AROUND 30 KNOTS.
AAG
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 020/040 023/030 017/038 023/046 025/046 027/039 020/030
11/B 66/J 10/N 00/N 01/U 11/B 13/J
LVM 024/036 025/028 020/036 025/043 027/043 029/036 022/026
13/J 75/J 10/N 00/N 11/N 12/W 23/J
HDN 018/040 020/031 012/039 018/047 022/047 024/040 018/032
21/B 66/J 10/B 00/U 01/U 11/B 12/J
MLS 019/038 017/031 009/037 017/047 022/046 022/038 016/031
11/B 32/J 10/B 00/U 00/B 01/B 12/J
4BQ 020/037 018/029 009/037 016/047 022/048 022/044 016/035
20/B 34/J 10/B 00/U 00/U 01/B 12/J
BHK 019/033 012/028 010/033 016/045 022/044 021/039 018/031
10/N 22/J 20/B 00/B 00/B 01/B 12/J
SHR 019/039 019/028 009/038 015/048 022/048 023/042 015/034
61/B 66/J 10/B 00/U 00/U 01/B 12/J
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
118 AM EST THU NOV 19 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM OVER THE WESTERN GREAT LAKES WILL PUSH A
COLD FRONT THROUGH OUR AREA THURSDAY, BRINGING WINDY CONDITIONS
WITH RAIN SHOWERS. COOLER AIR WILL FOLLOW THE FRONT FOR THE
WEEKEND WITH RAIN AND SNOW SHOWERS.
&&
.NEAR TERM /THROUGH TODAY/...
9 PM UPDATE...
AS FORECAST BY THE PREVIOUS SHIFT, THE SHOWER ACTIVITY IS SPARSE
AND STILL A WAYS OFF, DESPITE THE AGGRESSIVE PUSH NORTHEASTWARD BY
A PRIOR HRRR RUN.
MAIN CHANGE FOR THE OVERNIGHT PERIOD WAS TO INCREASE TEMPERATURES
TOWARD SUNRISE, AS WARM AIR IS MAKING A STRONG PUSH OUT OF PA INTO
SWRN NY.
4 PM UPDATE...
TGT GRADIENT WILL KEEP THE LOW CLDS AND WINDS UP OVRNGT...BUT THE
BULK OF THE SHWRS WILL HOLD OFF UNTIL THU. LOW CLDS CONT TO STREAM
NWRD WITH THE LL MOIST FLOW OFF THE WRN ATLANTIC. DOWNSLOPING HAS
LIMITED THE CLDS IN THE MOHAWK VALLEY INTO THE SYR AREA...BUT XPCT
THE CLDS TO EXPAND OVRNGT INTO THOSE AREAS. SC DECK HAS HELPED
MAINTAIN A MORE STABLE LYR NEARER THE SFC AND LIMITED THE AMT OF
HIGH WINDS THAT HAVE BEEN SEEN AT THE SFC. XPCT THIS TO CONT
OVRNGT WITH HEALTHY 40 KT GUSTS ZIPPING ALONG ABV. HIGHEST GUSTS
WILL CONT TO BE OVER THE HIGHER RIDGES OF THE FINGER LAKES...ESP
IN THE WEST.
WITH THE SHRP RDG HOLDING IN THE EAST AND THE UPR LOW WELL WEST
OVER ERN MN...RAIN WILL HOLD OFF FOR MUCH OF THE NGT...OTR THAN A
FEW SPRINKLES OVER THE EAST AND SOUTH. LTR TNGT...SHRT WV AND
DVLPG JET MAX WILL GENERATE A GOOD AREA OF PCPN PUSHING INTO THE
WRN ZONES ARND 09Z...AND CONTG TO SPREAD EAST.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
SOLID AREA OF PCPN MARCHES EAST ON SAT WITH THE WV AND UPR JET.
CAT POPS SEEM RSNBL GIVEN THE CONFIDENCE IN THE ABILITY OF THE FNT
TO GENERATE RAIN...AND THE HISTORY OF THE SYSTEM. FNT AND UPR
SUPPORT IS PROGRESSIVE AND WILL MSTLY BE EAST OF THE AREA BY 00Z
FRI. RAINFALL AMTS SHD NOT BE EXCESSIVE WITH THE MVMT AND SPEED OF
THE FNT...GNRLY LESS THAN 3/4 INCH.
IN THE WAKE OF THE FNT AND WV...AREA REMAINS IN A BROAD UPR TROF
CNTRD OVER CNTRL LAKES. SWLY FLOW CONTS THRU THE END OF THE SHRT
TERM. WITH MRNGL H8 TEMPS AND FLOW DIRECTION NOT FVRBL FOR THE
FCST AREA...XPCT VERY LIMITED LE SHWRS THRU SAT...WITH THE BEST
CHANCE FOR ISLTD RAINS SHWRS OVER THE FINGER LAKES.
TEMPS WILL DROP CONSIDERABLY AFT THU BUT STILL MAY BE SLGTLY ABV
NRML FOR MID NOV.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A SHORTWAVE TROUGH WILL START TO MOVE THROUGH THE REGION SATURDAY
EVENING AND FORCE A SFC LOW ACROSS THE AREA. THIS SYSTEM WILL BRING
COOLER TEMPS ALONG WITH THE CHANCE FOR RAIN/SNOW SHOWERS. THE UPPR
LVL TROUGH WILL SLOWLY MOVE EAST AND SHIFT EAST OF THE REGION BY
MONDAY EVENING. LAKE EFFECT SHOWERS WILL FOLLOW IN THE SYSTEM`S
WAKE. HIGH PRESSURE WILL BUILD OVER CENTRAL NY AND NORTHEAST PA ON
TUESDAY PUTTING AN END TOWARDS SHOWERS OVER THE REGION. LARGE
DISCREPANCIES EXIST WITHIN GUIDANCE STARTING THURSDAY OF NEXT WEEK
THROUGH THE EXTENDED PORTION OF THE FORECAST. DECIDED TO KEEP THE
FORECAST DRY AS CONFIDENCE IS LOW ON ANY SOLUTION.
TEMPS DURING THE FORECAST PERIOD WILL BE CLOSE TO THE SEASONAL
AVERAGE.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AN OCCLUDED FRONT IS SET TO CARRY WEST TO EAST ACROSS THE
TERMINALS THIS COMING AFTERNOON. WELL AHEAD OF IT...AN UPPER WAVE
WILL SPREAD SHOWERS OVER THE AREA. ALSO OCCURRING IN ADVANCE OF
THE FRONT...A STRONG SOUTHERLY 50-60 KT LOW LEVEL JET WILL
CONTINUE TO PRODUCE LOW LEVEL WIND SHEAR FOR ALL TERMINALS FOR THE
REMAINDER OF THE NIGHT INTO EARLY MORNING...AND FOR KSYR-KRME
EVEN UP TO ABOUT MIDDAY. CIGS WILL BE MAINLY MVFR...INTO FUEL ALT
REQ LEVELS FOR KBGM-KITH-KELM-KAVP WHILE MAINLY HIGHER END MVFR
KSYR-KRME AHEAD OF THE FRONT. KBGM-KAVP WILL PROBABLY DIP INTO
IFR CAT AROUND FRONTAL PASSAGE LATE AFTERNOON-EARLY EVENING WITHIN
ROUND OF HEAVIER SHOWERS...WHILE KSYR-KRME SHOULD REACH FUEL ALT
CIGS WITH THE FRONT. WINDS GENERALLY SSE-SSW IN LOW TO MID TEENS
WITH GUSTS IN THE 20S KTS RANGE...EXCEPT FOR LOCALIZED ESE AT
KRME AROUND 12 KTS. SW TO W VEERING WILL OCCUR BEHIND THE FRONT
LATE AFTERNOON-EVENING AS WIND SPEED ALSO DIMINISHES.
.OUTLOOK...
FRIDAY-SATURDAY...VFR.
SAT NIGHT...COLD FRONTAL PASSAGE WITH RAIN SHOWERS CHANGING TO
SNOW SHOWERS...AND ASSOCIATED POSSIBLE RESTRICTIONS.
SUN THROUGH MON...RESTRICTIONS AT TIMES IN MIXED SHSN AND SHRA...MAINLY
CENTRAL NY TERMINALS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
NEAR TERM...DGM/DJP
SHORT TERM...DGM
LONG TERM...KAH
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
410 AM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL CROSS CENTRAL NORTH CAROLINA THIS
AFTERNOON AND EVENING...FOLLOWED BY HIGH PRESSURE BUILDING OVER THE
REGION ON FRIDAY. A MOISTURE STARVED COLD FRONT WILL SWEEP
ACROSS THE REGION SATURDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 410 AM THURSDAY...
A LARGE AREA OF RAIN... WITH A FEW EMBEDDED CONVECTIVE ELEMENTS...IS
CURRENTLY TRANSLATING EAST ACROSS THE FORECAST AREA AS A 50KT
PREFRONTAL LOW-LEVEL JET LIFTS NORTH TOWARD THE MID-ATLANTIC STATES
9PER REGIONAL VWP). THE CONVECTIVE ELEMENTS LACK ANY LIGHTNING OR
STRONG WIND SIGNATURES...AND GIVEN THE LACK OF ANALYZED INSTABILITY
NORTH OF THE SAVANNAH RIVER BASIN...WE MAY BE FREE OF THUNDERSTORMS
FOR THE EARLY MORNING HOURS. LATER THIS MORNING...VEERING SURFACE
WINDS AHEAD OF THE MAIN COLD FRONT...WHICH IS CURRENTLY MOVING
THROUGH NORTHERN GEORGIA AND EASTERN TN/KY...SHOULD TAP INTO NEAR 70
DEWPOINT AIR OVER EAST-CENTRAL SC AND LEAD TO SOME WEAK
DESTABILIZATION (250-500 J/KG MLCAPE) FROM THE SANDHILLS INTO THE
COASTAL PLAIN BY MIDDAY. THERE IS NO REAL CONSENSUS IN NEAR TERM
GUIDANCE REGARDING THE COVERAGE OF ADDITIONAL SHOWERS AND
STORMS...SOME SHOW A BROKEN LINE AND SOME SHOW JUST SCATTERED
CONVECTION. THE BACK EDGE TO THE DEEP MOISTURE IS RAPIDLY
PUSHINGEAST ACROSS THE MOUNTAINS AND IS OUTPACING THE COLD
FRONT....SO DEEP MISTURE WILL BE LACKING BY THE TIME THE FRONT
ARRIVES. HOWEVER...THE RAP SHOWS A PRE-FRONTAL TROUGH THAT MAY
PROVIDE A FOCUS FOR SOME SCATTERED CONVECTION...MAINLY US 1 AND EAST
BY MIDDAY...AND A FEW ADDITIONAL SHOWERS EVEN POSSIBLE WITH THE
PRIMARY COLD FRONT LATER THIS AFTERNOON AND EVENING. IF SOME
MODERATELY DEEP CONVECTION CAN INITIATE TODAY...0-6KM BULK SHEAR
VALUES OF 35-45KT WOULD CERTAINLY SUPPORT A DAMAGING WIND THREAT.
HIGHS WILL CLIMB BACK INTO THE MID 70S IN MOST AREAS...PARTICULARLY
IN THE WEST BEHIND THE CLEARING BUT AHEAD OF THE FRONT.
THE COLD FRONT WILL SWEEP ACROSS THE AREA BY EARLY EVENING...LEADING
TO COLD ADVECTION FOR MOST OF THE OVERNIGHT PERIOD AND LOWS DROPPING
INTO THE 40S FOR MOST OF CENTRAL NC.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 345 AM THURSDAY...
BENEATH BRIEF HEIGHT RISES IN BROAD WSW FLOW ALOFT... CONTINENTAL
POLAR HIGH PRESSURE AND AN ASSOCIATED DEEPLY DRY AIR MASS WILL BUILD
EAST ACROSS THE TN VALLEY AND APPALACHIANS THROUGH FRI NIGHT. THE
RIDGE WILL BE SHORT-LIVED HOWEVER...AS A SHARP SHORTWAVE TROUGH AND
"ALBERTA CLIPPER" LOW AMPLIFY INTO THE CENTRAL PLAINS/MID MS VALLEY
REGION...THEN LIFT/TURN NORTHEASTWARD THROUGH THE GREAT LAKES SAT-
SAT NIGHT. AN ASSOCIATED TRAILING POLAR FRONT WILL MOVE EAST ACROSS
CENTRAL NC SAT NIGHT-EARLY SUNDAY. AT THE SAME TIME...THE MODELS TO
VARYING DEGREES INDICATE AN ACTIVE SOUTHERN STREAM JET WILL SUPPORT
A WAVE OR WAVES OF LOW PRESSURE ALONG A DEVELOPING/SHARPENING
COASTAL FRONT ALONG THE SOUTHEAST US COAST...RAISING THE STAKES FOR
SOME INTERACTION OF THE TWO AS THE POLAR FRONT COLLAPSES EAST AND
INTERCEPTS DEEPENING MOISTURE CENTERED ALONG THE COASTAL CAROLINAS.
WHILE THE GFS REMAINS DRY...WITH MORE LIMITED DEEP MOISTURE OVER
CENTRAL NC...THE CONSENSUS OF OTHER GUIDANCE INCLUDING THE LATEST
EC/NMM/SREF/GEM...ALL SUPPORT VERY LIGHT QPF OVER THE EASTERN
PIEDMONT/SANDHILLS/COASTAL PLAIN SAT NIGHT...AT WHICH TIME A SLIGHT
CHANCE OF SHOWERS HAVE ACCORDINGLY BEEN INTRODUCED GENERALLY EAST OF
US HIGHWAY 1.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM THURSDAY...
THE 00Z/19TH ECMWF IS AN AGGRESSIVE OUTLIER THAT HOLDS THE
ASSOCIATED MERGED FRONTAL ZONE JUST OFFSHORE THROUGH SUN
NIGHT...WITH AN AXIS OF A QUARTER TO HALF INCH OF QPF LINGERING AS
FAR WEST AS THE I-95 CORRIDOR DURING THAT TIME. WILL FOLLOW WPC/S
PREFERENCE TOWARD A MORE PROGRESSIVE FRONTAL DEPARTURE AND
INCREASINGLY INFLUENTIAL...AND RENEWED...CONTINENTAL POLAR RIDGING
FROM THE WEST FOR THE PERIOD SUNDAY THROUGH MID-WEEK. THE ASSOCIATED
COOLEST TEMPERATURES WILL OCCUR SUN-MON...WITH HIGHS MOSTLY IN THE
UPPER 40S TO LOW 50S...AND LOWS IN THE MID-UPPER 20S...AND WITH
MODERATION INTO THE 50S AND 30S...RESPECTIVELY...THROUGH THE END OF
THE PERIOD.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 120 AM THURSDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD AS A FRONTAL SYSTEM BRINGS HEAVY RAIN AND GUSTY WINDS TO THE
AREA. A BAND OF SHOWERS IS CURRENTLY SHIFTING EASTWARD ACROSS
CENTRAL NC... ALONG WITH IFR/LOW END MVFR CONDITIONS. THE MAIN BAND
OF PRECIP SHOULD SHIFT TO THE EAST OF THE AREA BY AROUND 15Z OR SO.
HOWEVER... CIGS WILL CONTINUE TO REMAIN IN THE MVFR RANGE UNTIL THE
MAIN FRONT MOVES ACROSS THE AREA... ALONG WITH POSSIBLY SOME
LINGERING SHOWERS ACROSS THE EASTERN TAF SITES. IN ADDITION... A
BROKEN BAND OF SHOWERS AND ISOLATED STORMS MAY FORM ALONG/JUST IN
ADVANCE OF THE FRONT AS IT MOVES EASTWARD ACROSS THE AREA ON
THURSDAY AFTERNOON ACROSS THE EASTERN TAF SITES (MAINLY KRWI/KFAY).
IN ADDITION TO THE PRECIP...GUSTY WINDS CAN BE EXPECTED...WITH
SUSTAINED WIND SPEEDS OF 10-15 KTS GUSTING POSSIBLY AS HIGH AS 25
KTS BUT MORE LIKELY 15-20 KTS AT PERIODS UNTIL MID MORNING OR SO. AS
THE FRONT MOVES THROUGH A GIVEN LOCATION WIND WILL BECOME
NORTHWESTERLY... POSSIBLY BECOMING GUSTY FOR A BRIEF PERIOD AS WELL
(15-20 KT GUSTS).
OUTLOOK: EXPECT A RETURN TO VFR CONDITIONS WITH A VERY SLIGHT CHANCE
OF PRECIPITATION WITH A FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING
BUT OTHERWISE DRY CONDITIONS SHOULD PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...22
SHORT TERM...26
LONG TERM...26
AVIATION...77/ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
400 AM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH THE MOUNTAINS FROM THE WEST
THIS EVENING...THEN TRACK EAST ACROSS THE CAROLINAS THURSDAY. HIGH
PRESSURE WILL BUILD INTO THE REGION FROM THE WEST ON FRIDAY. A
MAINLY DRY COLD FRONT WILL SWEEP ACROSS THE AREA SATURDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 1030 PM WEDNESDAY...
DEEP MID/UPPER LEVEL TROUGH CENTERED OVER THE CENTRAL PART OF THE
COUNTRY WILL CONTINUE TO SLOWLY SHIFT EASTWARD TONIGHT... WHILE THE
MAIN STACK LOW PRESSURE CENTER WILL CONTINUE TO LIFT NORTH-
NORTHEASTWARD OVERNIGHT INTO SOUTHERN CANADA. THE ASSOCIATED SURFACE
COLD FRONT WILL CONTINUE TO APPROACH THE AREA FROM THE WEST
OVERNIGHT... CURRENTLY EXTENDED SOUTHWARD FROM THE TN/KY INTO
EASTERN AL. THE FRONT SHOULD REMAIN TO THE WEST OF THE AREA
OVERNIGHT THOUGH. HOWEVER... A PREFRONTAL BAND OF SHOWERS AND EVEN
SOME ISOLATED THUNDERSTORMS WILL MOVE INTO THE AREA TONIGHT (MOVING
INTO WESTERN PORTIONS OF THE AREA NOW). THE BEST DYNAMICS WILL PASS
TO THE NORTH OF THE AREA AS THE MID LEVEL TROUGH DEAMPLIFIES AND
BROADENS. HOWEVER... WITH A GOOD SOUTHERLY LOW LEVEL FLOW AND STILL
GOOD MOISTURE TRANSPORT WE SHOULD SEE PW`S CLIMB TO AROUND 1.75" TO
2.0" OVERNIGHT. THUS... WE WILL SEE SOME MODERATE TO AT TIMES HEAVY
RAIN. HOWEVER... WITH FLASH FLOOD GUIDANCE GENERALLY ABOVE 2 INCHES
FOR ONE HOUR AND AROUND 2.5 TO 3 INCHES FOR 3 HOURS... THINK WE
SHOULD BE OK OUTSIDE OF POSSIBLY SOME MINOR FLOODING IN URBAN AREAS
(BEST CHANCES ACROSS THE TRIAD... WHERE WE COULD SEE RAINFALL
AMOUNTS OF AROUND 1 TO 1.5 INCHES). WITH REGARD TO A SEVERE
THREAT... THE LATEST RAP AND GFS CONTINUE TO SHOW WEAK INSTABILITY
INCREASING LATE TONIGHT WITH THE WAA... WITH UP TO 400-500 J/KG OF
MLCAPE BY AROUND 12Z ACROSS THE SOUTHWESTERN PIEDMONT AND SOUTHERN
SANDHILLS. THE LATEST DAY1 SPC CONVECTIVE OUTLOOK BRINGS THE
MARGINAL RISK VERY NEAR OUR SOUTHERN/SOUTHWESTERN COUNTIES. GIVEN
THE TIME OF DAY AND LACK OF ANY SEVERE WEATHER OVER THE LAST SEVERAL
HOURS... WOULD ANTICIPATE THIS THREAT TO BE QUITE SMALL... BUT NOT
ZERO GIVEN THE GOOD DEEP SHEAR (IF ENOUGH INSTABILITY ADVECTS
IN)...WITH THE MAIN THREAT FROM A VERY WEAK BRIEF TORNADO AND/OR
DAMAGING WIND GUST. TEMPS WILL GENERALLY REMAIN STEADY OVERNIGHT...
POSSIBLY EVEN INCREASING A DEGREE OR TWO ACROSS EASTERN PORTIONS OF
THE AREA... GENERALLY MID TO UPPER 60S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 345 AM THURSDAY...
BENEATH BRIEF HEIGHT RISES IN BROAD WSW FLOW ALOFT... CONTINENTAL
POLAR HIGH PRESSURE AND AN ASSOCIATED DEEPLY DRY AIR MASS WILL BUILD
EAST ACROSS THE TN VALLEY AND APPALACHIANS THROUGH FRI NIGHT. THE
RIDGE WILL BE SHORT-LIVED HOWEVER...AS A SHARP SHORTWAVE TROUGH AND
"ALBERTA CLIPPER" LOW AMPLIFY INTO THE CENTRAL PLAINS/MID MS VALLEY
REGION...THEN LIFT/TURN NORTHEASTWARD THROUGH THE GREAT LAKES SAT-
SAT NIGHT. AN ASSOCIATED TRAILING POLAR FRONT WILL MOVE EAST ACROSS
CENTRAL NC SAT NIGHT-EARLY SUNDAY. AT THE SAME TIME...THE MODELS TO
VARYING DEGREES INDICATE AN ACTIVE SOUTHERN STREAM JET WILL SUPPORT
A WAVE OR WAVES OF LOW PRESSURE ALONG A DEVELOPING/SHARPENING
COASTAL FRONT ALONG THE SOUTHEAST US COAST...RAISING THE STAKES FOR
SOME INTERACTION OF THE TWO AS THE POLAR FRONT COLLAPSES EAST AND
INTERCEPTS DEEPENING MOISTURE CENTERED ALONG THE COASTAL CAROLINAS.
WHILE THE GFS REMAINS DRY...WITH MORE LIMITED DEEP MOISTURE OVER
CENTRAL NC...THE CONSENSUS OF OTHER GUIDANCE INCLUDING THE LATEST
EC/NMM/SREF/GEM...ALL SUPPORT VERY LIGHT QPF OVER THE EASTERN
PIEDMONT/SANDHILLS/COASTAL PLAIN SAT NIGHT...AT WHICH TIME A SLIGHT
CHANCE OF SHOWERS HAVE ACCORDINGLY BEEN INTRODUCED GENERALLY EAST OF
US HIGHWAY 1.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM THURSDAY...
THE 00Z/19TH ECMWF IS AN AGGRESSIVE OUTLIER THAT HOLDS THE
ASSOCIATED MERGED FRONTAL ZONE JUST OFFSHORE THROUGH SUN
NIGHT...WITH AN AXIS OF A QUARTER TO HALF INCH OF QPF LINGERING AS
FAR WEST AS THE I-95 CORRIDOR DURING THAT TIME. WILL FOLLOW WPC/S
PREFERENCE TOWARD A MORE PROGRESSIVE FRONTAL DEPARTURE AND
INCREASINGLY INFLUENTIAL...AND RENEWED...CONTINENTAL POLAR RIDGING
FROM THE WEST FOR THE PERIOD SUNDAY THROUGH MID-WEEK. THE ASSOCIATED
COOLEST TEMPERATURES WILL OCCUR SUN-MON...WITH HIGHS MOSTLY IN THE
UPPER 40S TO LOW 50S...AND LOWS IN THE MID-UPPER 20S...AND WITH
MODERATION INTO THE 50S AND 30S...RESPECTIVELY...THROUGH THE END OF
THE PERIOD.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 120 AM THURSDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD AS A FRONTAL SYSTEM BRINGS HEAVY RAIN AND GUSTY WINDS TO THE
AREA. A BAND OF SHOWERS IS CURRENTLY SHIFTING EASTWARD ACROSS
CENTRAL NC... ALONG WITH IFR/LOW END MVFR CONDITIONS. THE MAIN BAND
OF PRECIP SHOULD SHIFT TO THE EAST OF THE AREA BY AROUND 15Z OR SO.
HOWEVER... CIGS WILL CONTINUE TO REMAIN IN THE MVFR RANGE UNTIL THE
MAIN FRONT MOVES ACROSS THE AREA... ALONG WITH POSSIBLY SOME
LINGERING SHOWERS ACROSS THE EASTERN TAF SITES. IN ADDITION... A
BROKEN BAND OF SHOWERS AND ISOLATED STORMS MAY FORM ALONG/JUST IN
ADVANCE OF THE FRONT AS IT MOVES EASTWARD ACROSS THE AREA ON
THURSDAY AFTERNOON ACROSS THE EASTERN TAF SITES (MAINLY KRWI/KFAY).
IN ADDITION TO THE PRECIP...GUSTY WINDS CAN BE EXPECTED...WITH
SUSTAINED WIND SPEEDS OF 10-15 KTS GUSTING POSSIBLY AS HIGH AS 25
KTS BUT MORE LIKELY 15-20 KTS AT PERIODS UNTIL MID MORNING OR SO. AS
THE FRONT MOVES THROUGH A GIVEN LOCATION WIND WILL BECOME
NORTHWESTERLY... POSSIBLY BECOMING GUSTY FOR A BRIEF PERIOD AS WELL
(15-20 KT GUSTS).
OUTLOOK: EXPECT A RETURN TO VFR CONDITIONS WITH A VERY SLIGHT CHANCE
OF PRECIPITATION WITH A FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING
BUT OTHERWISE DRY CONDITIONS SHOULD PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...77
SHORT TERM...26
LONG TERM...26
AVIATION...77/ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
120 AM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH THE MOUNTAINS FROM THE WEST
THIS EVENING...THEN TRACK EAST ACROSS THE CAROLINAS THURSDAY. HIGH
PRESSURE WILL BUILD INTO THE REGION FROM THE WEST ON FRIDAY. A
MAINLY DRY COLD FRONT WILL SWEEP ACROSS THE AREA SATURDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 1030 PM WEDNESDAY...
DEEP MID/UPPER LEVEL TROUGH CENTERED OVER THE CENTRAL PART OF THE
COUNTRY WILL CONTINUE TO SLOWLY SHIFT EASTWARD TONIGHT... WHILE THE
MAIN STACK LOW PRESSURE CENTER WILL CONTINUE TO LIFT NORTH-
NORTHEASTWARD OVERNIGHT INTO SOUTHERN CANADA. THE ASSOCIATED SURFACE
COLD FRONT WILL CONTINUE TO APPROACH THE AREA FROM THE WEST
OVERNIGHT... CURRENTLY EXTENDED SOUTHWARD FROM THE TN/KY INTO
EASTERN AL. THE FRONT SHOULD REMAIN TO THE WEST OF THE AREA
OVERNIGHT THOUGH. HOWEVER... A PREFRONTAL BAND OF SHOWERS AND EVEN
SOME ISOLATED THUNDERSTORMS WILL MOVE INTO THE AREA TONIGHT (MOVING
INTO WESTERN PORTIONS OF THE AREA NOW). THE BEST DYNAMICS WILL PASS
TO THE NORTH OF THE AREA AS THE MID LEVEL TROUGH DEAMPLIFIES AND
BROADENS. HOWEVER... WITH A GOOD SOUTHERLY LOW LEVEL FLOW AND STILL
GOOD MOISTURE TRANSPORT WE SHOULD SEE PW`S CLIMB TO AROUND 1.75" TO
2.0" OVERNIGHT. THUS... WE WILL SEE SOME MODERATE TO AT TIMES HEAVY
RAIN. HOWEVER... WITH FLASH FLOOD GUIDANCE GENERALLY ABOVE 2 INCHES
FOR ONE HOUR AND AROUND 2.5 TO 3 INCHES FOR 3 HOURS... THINK WE
SHOULD BE OK OUTSIDE OF POSSIBLY SOME MINOR FLOODING IN URBAN AREAS
(BEST CHANCES ACROSS THE TRIAD... WHERE WE COULD SEE RAINFALL
AMOUNTS OF AROUND 1 TO 1.5 INCHES). WITH REGARD TO A SEVERE
THREAT... THE LATEST RAP AND GFS CONTINUE TO SHOW WEAK INSTABILITY
INCREASING LATE TONIGHT WITH THE WAA... WITH UP TO 400-500 J/KG OF
MLCAPE BY AROUND 12Z ACROSS THE SOUTHWESTERN PIEDMONT AND SOUTHERN
SANDHILLS. THE LATEST DAY1 SPC CONVECTIVE OUTLOOK BRINGS THE
MARGINAL RISK VERY NEAR OUR SOUTHERN/SOUTHWESTERN COUNTIES. GIVEN
THE TIME OF DAY AND LACK OF ANY SEVERE WEATHER OVER THE LAST SEVERAL
HOURS... WOULD ANTICIPATE THIS THREAT TO BE QUITE SMALL... BUT NOT
ZERO GIVEN THE GOOD DEEP SHEAR (IF ENOUGH INSTABILITY ADVECTS
IN)...WITH THE MAIN THREAT FROM A VERY WEAK BRIEF TORNADO AND/OR
DAMAGING WIND GUST. TEMPS WILL GENERALLY REMAIN STEADY OVERNIGHT...
POSSIBLY EVEN INCREASING A DEGREE OR TWO ACROSS EASTERN PORTIONS OF
THE AREA... GENERALLY MID TO UPPER 60S.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 320 PM WEDNESDAY...
MODEL GUIDANCE REMAINS CONSISTENT AND IN FAIRLY GOOD AGREEMENT ON
THE TIMING OF THE COLD FRONT THROUGH CENTRAL NC BETWEEN MID MORNING
AND EARLY EVENING THU (ALTHOUGH THE CHILLIER AND MUCH DRIER AIR WILL
TAKE AWHILE LONGER TO SCALE THE MOUNTAINS). THE STEADY SHOWERS WILL
CROSS THE AREA A FEW HOURS AHEAD OF THE FRONT... FROM THE EARLY
MORNING PREDAWN HOURS THROUGH MID TO LATE AFTERNOON. ONCE AGAIN AN
ISOLATED STORM OR TWO IS POSSIBLE... PARTICULARLY EAST OF HIGHWAY 1
WHERE SOME EARLY-DAY HEATING AND SLIGHTLY HIGHER SURFACE DEWPOINTS
SHOULD PUSH UP THE RISK OF A FEW HUNDRED J/KG OF CAPE BY THE TIME
THE MAIN RAIN SHIELD ARRIVES... SO WILL GO WITH A SLIGHTLY HIGHER
THUNDER RISK IN THE FAR EAST. BY THIS TIME THE LOW-MID LEVEL WINDS
WILL BE FROM THE SW... FAVORING A LINEAR STRUCTURE TO ANY
CONVECTION... SO A FEW WEAK BOWING SEGMENTS WITH ENHANCED WIND GUSTS
CANNOT BE RULED OUT... BUT THE DECREASING BACKGROUND WINDS AND LOW
LEVEL SHEAR MAGNITUDES WILL LIMIT THE THREAT OF ANY VERY STRONG
WINDS. RAINFALL INTENSITY IS EXPECTED TO DECREASE A BIT AS THE BAND
SHIFTS OUT OF THE MOUNTAINS AND INTO THE PIEDMONT... A FUNCTION OF
THE DROPOFF IN LARGE SCALE LIFT... SO AMOUNTS ARE NOT EXPECTED TO
POSE A FLOODING THREAT. BUT GIVEN THE VIGOROUS LOW LEVEL MOISTURE
TRANSPORT... WE SHOULD STILL EXPECT STORM TOTAL AMOUNTS OF AROUND
1.0-1.5" WHICH MAY LEAD TO MINOR FLOODING IN URBAN AND LOW LYING
AREAS. PRECIP SHOULD BE TAPERING OFF DURING THE MID-LATE
AFTERNOON... WITH POPS GENERALLY ENDING BY 01Z AND CLEARING SKIES
FROM MID EVENING THROUGH THE NIGHT AS THE COLUMN DRIES AND
STABILIZES. HIGHS SHOULD REACH 72-78. LOWS 43-50. -GIH
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 225 PM WEDNESDAY...
FOR THE PERIOD FRIDAY THROUGH SATURDAY...A DRY AIR MASS BUILDS INTO
CENTRAL NORTH CAROLINA WITH AN 850MB THETA-E TROUGH...NEGATIVE K
INDICES...AND PRECIPITABLE WATER VALUES AT OR BELOW A HALF-INCH.
STRONGER UPPER-LEVEL WINDS ARE FORECAST NORTH OF CENTRAL NORTH
CAROLINA...AND WHERE THE GUIDANCE FORECASTS SOME UPPER-LEVEL
MOISTURE THIS RESIDES MAINLY NORTH OF CENTRAL NORTH CAROLINA IN
VICINITY OF THOSE HIGHER WINDS ALOFT. BUFR SOUNDINGS FROM BOTH THE
NAM AND GFS ARE DRY...EVEN AS A WEAK MID-LEVEL WAVE OR TWO MOVES
THROUGH THE AREA IN THE SOUTHWEST FLOW ALOFT.
925MB WINDS ARE NEARLY 30KT AT 12Z FRIDAY IN THE TIGHT GRADIENT
BEHIND THE FRONT...AS HIGH PRESSURE BUILDS EAST. EXPECT SOME BREEZY
CONDITIONS FOR A PART OF FRIDAY WITH MIXING...AND SOME WIND GUSTS
COULD BE BRIEFLY 25 TO 30 MPH PARTICULARLY IN THE INTERSTATE 95
CORRIDOR. THE GRADIENT RELAXES SOME BY FRIDAY NIGHT ALTHOUGH THERE
APPEARS TO BE ENOUGH GRADIENT FOR A LIGHT BUT NOTICEABLE WIND FOR
MUCH OF NIGHT ESPECIALLY EAST OF U.S. 1. THERE SHOULD BE SOME LESSER
GUSTS IN THE TEENS KNOTS EARLY SATURDAY WITH MIXING ACCORDING TO THE
BUFR SOUNDINGS BEFORE WINDS GRADUALLY DIMINISH...WITH POSSIBLY A
LATE-DAY GUST IN THE LOWER TEENS MPH NEAR THE TRIAD AS WINDS BECOME
SOUTHWEST. HIGHS ANTICIPATED FROM 1000-850MB THICKNESSES CORRESPOND
WELL TO THE CONSENSUS OF MAV AND GRIDDED MOS GUIDANCE...THE FORMER
WHICH HAS BEEN DIFFICULT TO BEAT OF LATE...FOR HIGHS IN THE UPPER
50S TO MID 60S FRIDAY AND MAINLY 55 TO 60 SATURDAY AS THICKNESSES
ARE JUST A FEW METERS LOWER THEN. OVERNIGHT LOWS FRIDAY NIGHT IN THE
30S.
FOR THE PERIOD SATURDAY NIGHT THROUGH WEDNESDAY...A SOUTHWEST FLOW
ALOFT CONTINUES EARLY IN THIS PART OF THE LONG-TERM PERIOD WITH A
MID-LEVEL TROUGH APPROACHING AND MOVING THROUGH CENTRAL NORTH
CAROLINA EARLY IN THE NEXT WORK WEEK. AHEAD OF THE TROUGH THE LONG-
TERM GUIDANCE DEVELOPS A WAVE ALONG AND JUST AHEAD OF A FRONTAL
BOUNDARY THAT PASSES THROUGH CENTRAL NORTH CAROLINA SATURDAY NIGHT
INTO SUNDAY...WHILE KEEPING THE SURFACE LOW PRESSURE AND MOST OF ITS
MOISTURE OFFSHORE. THE GFS REMAINS DRY WITH THE FRONTAL
PASSAGE...WHILE THE 12Z ECMWF HAS TRENDED WETTER WITH THE
FRONT...THE FORMER SHOWING STRONGER SURFACE RIDGING AHEAD OF THE
FRONT WHILE THE LATTER WEAKENS THE HIGH MORE WITH A SHARPER TROUGH.
IN ADDITION...BOTH THE GFS AND THE ECWMF TRY TO PROVIDE FOR VERY
MARGINAL QPF...BARELY MEASURABLE...QPF JUST EAST OF CENTRAL NORTH
CAROLINA POST-FRONTAL CLOSER TO LOW PRESSURE OFFSHORE. GIVEN THE DRY
AIR IN PLACE...UNCERTAINTY REGARDING THE ABILITY OF LOW PRESSURE TO
PUSH MOISTURE BACK INTO CENTRAL NORTH CAROLINA...AND THE LOW QPF
WHERE IT DOES EXIST...WILL KEEP PRECIPITATION CHANCES BELOW SLIGHT
FOR NOW AND MONITOR THE LONG-TERM GUIDANCE TRENDS FOR POSSIBLE
ADDITION OF LOW CHANCES ESPECIALLY WITH THE FRONT OVERNIGHT
SATURDAY.
AN UPPER RIDGE BUILDS IN LATE IN THE LONG-TERM PERIOD WHICH SHOULD
HELP TO MODERATE THE AIR MASS. COLDEST TEMPERATURES SHOULD BE SUNDAY
AND SUNDAY NIGHT WITH HIGHS SUNDAY STAYING IN...OR STRUGGLING TO GET
OUT OF...THE 40S AND OVERNIGHT LOWS SUNDAY NIGHT SOLIDLY IN THE 20S
ALMOST AREAWIDE. IT COULD ALSO BE MODESTLY BREEZY WITH MIXING SUNDAY
IN A GRADIENT BETWEEN HIGH PRESSURE TRYING TO BUILD IN AND LOW
PRESSURE OFFSHORE...ADDING A LITTLE TO THE CHILL.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 120 AM THURSDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD AS A FRONTAL SYSTEM BRINGS HEAVY RAIN AND GUSTY WINDS TO THE
AREA. A BAND OF SHOWERS IS CURRENTLY SHIFTING EASTWARD ACROSS
CENTRAL NC... ALONG WITH IFR/LOW END MVFR CONDITIONS. THE MAIN BAND
OF PRECIP SHOULD SHIFT TO THE EAST OF THE AREA BY AROUND 15Z OR SO.
HOWEVER... CIGS WILL CONTINUE TO REMAIN IN THE MVFR RANGE UNTIL THE
MAIN FRONT MOVES ACROSS THE AREA... ALONG WITH POSSIBLY SOME
LINGERING SHOWERS ACROSS THE EASTERN TAF SITES. IN ADDITION... A
BROKEN BAND OF SHOWERS AND ISOLATED STORMS MAY FORM ALONG/JUST IN
ADVANCE OF THE FRONT AS IT MOVES EASTWARD ACROSS THE AREA ON
THURSDAY AFTERNOON ACROSS THE EASTERN TAF SITES (MAINLY KRWI/KFAY).
IN ADDITION TO THE PRECIP...GUSTY WINDS CAN BE EXPECTED...WITH
SUSTAINED WIND SPEEDS OF 10-15 KTS GUSTING POSSIBLY AS HIGH AS 25
KTS BUT MORE LIKELY 15-20 KTS AT PERIODS UNTIL MID MORNING OR SO. AS
THE FRONT MOVES THROUGH A GIVEN LOCATION WIND WILL BECOME
NORTHWESTERLY... POSSIBLY BECOMING GUSTY FOR A BRIEF PERIOD AS WELL
(15-20 KT GUSTS).
OUTLOOK: EXPECT A RETURN TO VFR CONDITIONS WITH A VERY SLIGHT CHANCE
OF PRECIPITATION WITH A FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING
BUT OTHERWISE DRY CONDITIONS SHOULD PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...77
SHORT TERM...HARTFIELD
LONG TERM...DJF
AVIATION...77/ELLIS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1233 AM EST THU NOV 19 2015
.SYNOPSIS...
MODERATE RAIN IS EXPECTED OVERNIGHT BEFORE A COLD FRONT PUSHES
ACROSS PENNSYLVANIA ON THURSDAY. IT WILL DRY OUT THURSDAY NIGHT
INTO FRIDAY AS HIGH PRESSURE BUILDS INTO THE UPPER OHIO VALLEY. A
SECOND COLD FRONT WILL MOVE THROUGH LATE IN THE WEEKEND. THE MILD
TEMPERATURES WILL PEAK ON THURSDAY FOLLOWED BY A COLDER PATTERN
FOR THE WEEKEND INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
05Z OBS AND MDL SOUNDINGS SUGGEST WGUSTS WILL REMAIN BLW ADVISORY
CRITERIA ACROSS THE LAUREL HIGHLANDS...SO HAVE ALLOWED WIND ADV
OVR SOMERSET/CAMBRIA COS TO EXPIRE. REGIONAL RADAR MOSAIC AT 05Z
SHOWS A SOLID LINE OF RAIN MOVING INTO WESTERN PA ASSOC WITH PLUME
OF ANOMALOUS PWATS AHEAD OF APPROACHING SHORTWAVE. RADAR TRENDS
AND LATEST SREF/GEFS OUTPUT SUPPORT POPS CLOSE TO 100 PCT
OVERNIGHT. ALTHOUGH AREAS OF DZ HAVE FORMED ACROSS THE EASTERN
HALF OF THE STATE...THE MORE SIG RAIN REMAINS WEST OF KUNV/KAOO AT
05Z. LINEAR EXTRAPOLATION AND HRRR GUIDANCE INDICATE THE MORE SIG
RAIN WILL REACH THE SUSQ RIVER BTWN 08Z-09Z AND
SCHUYLKILL/LANCASTER COS BY 10Z-11Z.
TEMPS WILL LIKELY FALL A COUPLE OF DEGREES AS RAIN ARRIVES...BUT
IT WILL REMAIN A VERY WARM NIGHT FOR NOVEMBER DUE TO SOUTHERLY
FLOW/SURGE OF WARMTH AHEAD OF APPROACHING COLD/OCCLUDED FRONT.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM FRIDAY/...
AREA OF RAIN WILL PUSH INTO THE SUSQUEHANNA VALLEY EARLY THURSDAY
BEFORE SHIFTING EAST INTO NJ LATER IN THE AFTERNOON/EVENING. STORM
TOTAL QPF AMTS ARE SOLIDLY IN THE 0.50 TO 1 INCH RANGE WITH SOME
LOCALIZED HIGHER AMOUNTS POSSIBLE ESPECIALLY IN REGIONS WHERE THE
OROGRAPHICS FOCUS AND ENHANCE LOW LEVEL LIFT. THE HI-RES SHORT
TERM MODELS AND ENSEMBLES SHOW THIS SE FLOW TERRAIN ENHANCEMENT
PRETTY WELL. PWS QUICKLY DECREASE AS MUCH DRIER AIR ARRIVES FROM
WEST TO EAST BEHIND THE FRONT DURING THE DAY ON THURSDAY. THIS
SHOULD BRING AN END TO THE SHOWERS OVER EASTERN PORTIONS OF THE
CWA BY 00Z FRIDAY.
TEMPS WILL PEAK ON THURSDAY WITH HIGHS 10-15 DEGREES ABOVE
CLIMO...BEFORE COLDER AIR WORKS IN THU NIGHT.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD INTO THE REGION FRIDAY WITH COOLER AND
DRIER WEATHER. EXTENDED MODELS STARTING TO COME TO SOME AGREEMENT
ON THE THE STORM TRACK AND AMOUNT OF COLDER AIR MOVING INTO THE
STATE LATER SATURDAY. 850 TEMPS SHOULD DROP BELOW ZERO OVER THE
ENTIRE STATE SATURDAY NIGHT WITH SNOW SHOWERS ACROSS THE NORTHWEST
AND A FEW FLURRIES OVER THE SOUTHEAST.
COOLER AIR CONTINUES INTO THE FIRST HALF OF THE WEEK BEFORE A
RETURN TO THE RELATIVELY MILD PATTERN BY MIDWEEK. ANOTHER HIGH
PRESSURE MOVING SOUTHEAST THROUGH NEW ENGLAND BY THE END OF THE
PERIOD MAY TEMPER THE MILD READINGS WITH A POSSIBLE BACK DOOR
FRONT LATE IN THE PERIOD.
&&
.AVIATION /05Z THURSDAY THROUGH MONDAY/...
SOME ADJUSTMENTS MADE TO THE TAFS THIS EVENING. SMALL
BANDS OF DRIZZLE AHEAD OF BAND OF SHOWERS OVER WESTERN PA
AT 11 PM.
EARLIER DISCUSSION BELOW.
GUSTY WINDS AND LLWS WILL BE THE MAIN ISSUE OVERNIGHT.
EXPECT LOW CIGS ACROSS THE WEST...ALONG WITH SOME RAIN AND
SHOWERS.
FURTHER EAST...STILL A FEW SPOTS WITH VFR CONDITIONS...BUT
EXPECT CONDITIONS TO BECOME MVFR AND IFR LATER ON.
SOME HZ/BR AT UNV AT TIMES SINCE MID AFT.
MAIN LINE OF SHOWERS STILL WELL TO THE WEST. SEPERATE AREA OF
SHOWERS JUST SOUTH OF JST.
PERHAPS A RUMBLE OF THUNDER WITH THE COLD FRONT...BUT 500 MB
HEIGHTS REALLY ARE NOT THAT LOW...AND INSTABILITY LIMITED
THIS TIME OF DAY.
IMPROVING CONDITIONS FOR THE LATER PART OF THU...AS DRY
SLOT MOVES IN.
OUTLOOK...
FRI...NO SIG WX EXPECTED.
SAT-SUN...LIGHT SNOW/REDUCED VSBYS POSSIBLE W MTNS SAT AFTERNOON
INTO SUNDAY...WITH MAINLY VFR IN MORE SCATTERED SNOW OR RAIN
SHOWERS CENTRAL AND SE PA.
MON...IMPROVING CONDITIONS AS HIGH PRESSURE BUILDS IN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/RXR
NEAR TERM...DANGELO/FITZGERALD
SHORT TERM...RXR
LONG TERM...STEINBUGL/TYBURSKI
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1229 AM EST THU NOV 19 2015
.SYNOPSIS...
WIDESPREAD RAINFALL IS EXPECTED TONIGHT AND TOMORROW MORNING AHEAD
OF A COLD FRONT. AFTER THE FRONTAL PASSAGE TOMORROW MORNING...COOL
AND DRY HIGH PRESSURE WILL MOVE BACK OVER THE REGION AND REMAIN IN
PLACE THROUGH SATURDAY. ANOTHER COLD FRONT WILL CROSS THE AREA ON
SUNDAY...WITH EVEN COLDER HIGH PRESSURE SPREADING OVER THE REGION IN
ITS WAKE.
&&
.NEAR TERM /THROUGH TODAY/...
0515 UTC UPDATE...POPS AND QPF HAVE BEEN ADJUSTED PER RADAR TRENDS.
WINDS WERE UDPATED WITH A BLEND OF THE LATEST NAM AND ADJMAV
GUIDANCE. THE TORNADO WATCH HAD BEEN CANCELLED FOR OUR GA AND SC
COUNTEID PER COORDINATION WITH SPC.
915 PM UPDATE...PREFRONTAL BAND OF RAIN NOW COVERS MOST OF THE CWFA
WEST OF I-77. EMBEDDED WITHIN ARE A FEW LINEARLY ORIENTED CONVECTIVE
BANDS THOUGH NOT EVEN LIGHTNING HAS BEEN DETECTED IN OUR AREA OVER
THE PAST HOUR OR SO. INSTABILITY IS PROVING HARD TO COME BY SO
FAR. RAP HAS BACKED OFF/DELAYED EARLIER PROGS OF INCREASING SBCAPE
OVER OUR LOWER PIEDMONT AREAS...NOW SUGGESTING THEY WON/T SEE MUCH
FORM UNTIL WELL AFTER MIDNIGHT. BACK EDGE OF THE PRECIP SHIELD
LOOKS LIKELY TO WORK INTO OUR WRNMOST ZONES IN THE NEXT COUPLE
HOURS. A PENCIL-THIN BAND OF ACTIVITY IS ORIENTED RIGHT ALONG
THE SFC FRONT OVER THE CUMBERLAND PLATEAU...AND DESPITE STRONG
UPPER FORCING THIS DOES NOT STAND MUCH CHANCE OF STRENGTHENING
AS IT ENCOUNTERS THE MTNS. PRESENT PLANS ARE TO KEEP THE TORNADO
WATCH IN EFFECT UNTIL 300 A.M. BUT THE WINDOW OF OPPORTUNITY IS
CURRENTLY SHRINKING...IT WOULD APPEAR.
AS FAR AS HYDRO...MOST SITES AWAY FROM UPSLOPE AREAS ARE REPORTING
RATES OF 0.15 TO 0.5 INCHES PER HOUR IN GENERAL...WITH SIGNIFICANT
ENHANCEMENT COMING AS CONVECTIVE FEATURES PASS THROUGH. RATES/ACCUMS
REPORTED BY MESONET GAGES ALONG THE ESCARPMENT OF COURSE ARE
SUBSTANTIALLY HIGHER. I REVISED QPF AND THE STORM TOTAL PRODUCT WITH
EXTRA WEIGHT ON THE HIGH-RES GUIDANCE WHICH AS A WHOLE REFLECTS A
SIMILAR DISTRIBUTION OF PRECIP. WE ARE SEEING SOME LOCALIZED FLOOD
ISSUES IN THE USUAL AREAS IN THE FOOTHILLS. THE LATER POSSIBILITY
OF CONVECTION HOWEVER DOES STILL IMPLY SOME LONGER-DURATION TYPE
ISSUES MAY RESULT OVER PARTS OF THE UPSTATE.
AS OF 235 PM...MID AFTERNOON KGSP WSR-88D VWP INDICATES 3-6 KFT
WINDS WERE FROM THE SE BETWEEN 40-45 KTS. NEAR TERM MODELS INDICATE
THAT MOISTURE SOURCED FROM THE GULF OF MEXICO AND THE WESTERN
ATLANTIC WILL LIFT ACROSS NE GA AND THE WESTERN CAROLINAS...PW
VALUES WILL RISE TO NEAR 2 INCHES BY 23Z. THE COMBINATION OF
STRONG UPSLOPE FLOW AND DEEP MOISTURE WILL SUPPORT A SOLID 4 TO
6 HOURS OF ADDITIONAL UPSLOPE MODERATE RAINFALL ALONG THE EAST
FACING SLOPES BEFORE THE PRE FRONTAL CONVECTIVE BAND ARRIVES. AS
OF 230 PM...OBSERVED RAINFALL TOTALS RANGED FROM 3.2 INCHES NEAR
LAKE TOXAWAY TO 1 TO 1.5 INCHES ACROSS THE SALUDA GRADE.
THIS EVENING...12Z GFS INDICATES A LARGE FIELD OF Q-VECTOR
CONVERGENCE WILL SPREAD ACROSS THE FORECAST AREA LATE THIS AFTERNOON
AND EVENING. AT H3...THE RIGHT ENTRANCE REGION OF A SOUTH-NORTH
160KT JET WILL SLIDE OVER THE CWA...EXITING AFTER 3Z.
CAMS INDICATE THAT A WIDE BAND PRE FRONTAL BAND OF CONVECTION WILL
SLIDE EAST ACROSS EASTERN TN/NRN GA BETWEEN 23Z TO 1Z. NAM FORECAST
SOUNDINGS ALONG AND AHEAD OF THE CONVECTIVE BAND INDICATES 0-1
KM SHEAR OVER 400 M2/S2...AND 300-500 J/KG OF SB CAPE...AND 0-1
KM EHI AS HIGH AS 1.25 M2/S2 ACROSS THE LAKELANDS. INSTABILITY
PARAMETERS RISE AFTER 0Z THURS. IN ADDITION TO MODERATE TO HEAVY
RAIN SHOWERS...I WILL INCREASE THE MENTION OF TSRA ACROSS THE
UPPER SAVANNAH RIVER VALLEY ACROSS THE PIEDMONT. IN AGREEMENT WITH
UPDATED DY1 CONVECTIVE OUTLOOK...I WILL ADD A MENTION OF SVR TSRA
ACROSS THE UPPER SAVANNAH RIVER VALLEY IN THE HWO.
SIGNIFICANT SYNOPTIC SCALE DYNAMICS...STRONG UPSLOPE FLOW...AND
A PASSING WINDOW FOR DEEP CONVECTION SHOULD RESULT IN HEAVY
RAINFALL RATES THIS EVENING AND INTO EARLY THURSDAY MORNING. IT
IS POSSIBLE THAT RAINFALL RATES COULD EXCEED THE 1-3 HR FFG ACROSS
THE MTNS...FOOTHILLS...THE WESTERN UPSTATE...AND EXTREME NE GA. IN
ADDITION...A COUPLE OF OPERATIONAL FORECASTS ALONG MAIN STEM RIVERS
INDICATE STAGES ABOVE FLOOD STAGE. I WILL CONTINUE TO HIGHLIGHT
THE RAINFALL THREAT WITH A FLASH FLOOD WATCH INTO THURSDAY MORNING.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
AS OF 215 PM EST...BRIEF AND SHALLOW NW FLOW MOISTURE WILL QUICKLY
DISSIPATE ACROSS THE NORTHERN MOUNTAINS THURSDAY EVENING.
OTHERWISE...AN UPPER CYCLONE OVER THE WESTERN GREAT LAKES WILL LIFT
NORTHEAST INTO CANADA THURSDAY NIGHT THROUGH FRIDAY LEAVING
RELATIVELY ZONAL FLOW IN PLACE OVER THE SOUTHEAST. UNDER THE ZONAL
FLOW...SPRAWLING SURFACE HIGH PRESSURE WILL BUILD EASTWARD FROM THE
MID MS RIVER VALLEY TO THE APPALACHIANS THROUGH LATE WEEK. TEMPS
CLOSE TO CLIMO FRI WILL FALL BELOW CLIMO SATURDAY WITH NE WINDS
AROUND THE SFC HIGH. MEANWHILE...A TROUGH WILL DIG FROM THE NORTHERN
PLAINS INTO THE MIDWEST FRIDAY NIGHT THROUGH SATURDAY. THIS SYSTEM
WILL PUSH A REINFORCING COLD FRONT AND A NARROW BAND OF MOISTURE TO
THE SPINE OF THE SOUTHERN APPALACHIANS BY LATE DAY ON SATURDAY. VERY
LITTLE MOISTURE RECOVERY IS EXPECTED AHEAD OF THE FRONTAL
SYSTEM...WITH JUST LATE DAY SLIGHT CHANCES OF SHOWERS IN THE WESTERN
MOUNTAINS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 215 PM WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
SUNDAY WITH STEEP UPPER TROFFING CENTERED OVER THE GREAT LAKES AND
UPPER RIDGING OVER THE WESTERN CONUS. THE MODELS DIFFER WRT THE
PROGRESSION OF THE TROF OVER THE NEXT 24 TO 48 HRS. THE LATEST 12Z
GFS AMPLIFIES THE SYSTEM AND MOVES THE TROF AXIS RIGHT OVER THE CWFA
LATE SUN/EARLY MON AND THEN QUICKLY MOVES THE SYSTEM OFFSHORE. THE
PATTERN FLATTENS OUT IN THE TROFS WAKE WITH HEIGHTS SLOWLY RISING
FOR THE REMAINDER OF THE PERIOD. THE ECMWF...ON THE OTHER
HAND...LIFTS THE TROF NE OF THE REGION ON SUN WHILE SIMULTANEOUSLY
DEVELOPING A POTENT SHORTWAVE ON THE BACKSIDE OF THE MAIN TROF. THIS
SHORTWAVE QUICKLY APPROACHES THE FCST AREA FROM THE WEST EARLY MON
AND MOVES OVERHEAD LATER THAT DAY. THE REMAINDER OF THE FCST IS
SIMILAR TO THE GFS WITH HEIGHTS RISING AS UPPER RIDGING MOVES BACK
OVER THE REGION THRU MIDWEEK.
AT THE SFC...A DRY COLD FRONT WILL BE MOVING INTO THE FCST AREA BY
THE START OF THE PERIOD AS ITS PARENT LOW PASSES OVER THE EASTERN
GREAT LAKES. THE FRONT IS EXPECTED TO MOVE THRU THE AREA QUICKLY
WITH COLD AND DRY HIGH PRESSURE OVERSPREADING THE REGION AGAIN IN
ITS WAKE. THE GFS HAS THE HIGH LINGERING OVER THE REGION THRU DAY 7
WITH IT SHIFTING NE TOWARDS NEW ENGLAND...HOWEVER THE ECMWF TRIES TO
SPIN UP A LOW OFF THE EAST COAST OF FLORIDA EARLY MON AND MOVE THE
SYSTEM NE OVER THE NEXT COUPLE OF DAYS. AT THE PRESENT TIME...IT
REMAINS FAR ENOUGH OFFSHORE THAT IT DOES NOT DIRECTLY IMPACT OUR
SENSIBLE WX. AS FOR THE SENSIBLE FCST...I ONLY KEEP A SLIGHT CHANCE
POP ALONG THE NC/TENN BORDER FOR EARLY SUN MORNING AS THE FRONT
MOVES THRU WITH DRY CONDITIONS AFTER THAT. THE TEMPS/THICKNESSES LOOK
COLD ENOUGH TO SUPPORT LIGHT SNOW SHOWERS IF PRECIP DOES
DEVELOP...BUT IT WOULD NOT AMOUNT TO MUCH. SIGNIFICANT CAA WILL KEEP
TEMPS WELL BELOW NORMAL THRU THE PERIOD WITH SOME WARMING ON TUES
AND WED AS THICKNESSES RECOVER.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AT KCLT...PRECIPITTAION AND ASSOCIATED RESTRICTIONS WILL CONTINUE
UNTIL EARLY MORNING. THEN AS THE COLD FRONT MOVES PAST...IMPROVEMENT
WILL OCCUR DURING THE MORNIGN. VFR WILL FOLLOW. WIDNS WILL VEER FROM
SE TO SW IN HTE MORNING...THEN TO NW IN THE AFTERNOON. GSUTS WILL
ACTUALLY DECREASE BY AFTERNOON.
ELSEWHERE...ALTHGOUHT PRECIPITIATIION WILL DECREASE OVERNIGHT...
RESTRICTIONS WILL PERSIST UNTIL DAWN...UNTIL DRIER AIR CAN ARRIVE
BEHIND THE DEPARTING COLD FRONT. WINDS WILL VEER FROM SE TO SW IN
HTE FOOTHILSL BY DAWN...AND FROM SE TO NW AT KAVL. FOOTHILLS WINDS
VEER NW BY AFTERNOON...WITH GUSTS DECREASING.
OUTLOOK...DRY HIGH PRESSURE WILL BRING VFR CONDITIONS FOR THURSDAY
NIGHT AND FRIDAY. A SECONDARY COLD FRONT COULD BRING SOME LIGHT SNOW
AND MINOR VSBY RESTRICTIONS TO THE HIGHER NC MTNS SATURDAY NIGHT.
CONFIDENCE TABLE...
05-11Z 11-17Z 17-23Z 23-00Z
KCLT HIGH 100% LOW 55% MED 62% HIGH 94%
KGSP MED 69% MED 75% HIGH 81% MED 78%
KAVL HIGH 87% LOW 41% HIGH 100% MED 66%
KHKY HIGH 100% HIGH 94% HIGH 81% MED 72%
KGMU MED 69% MED 61% HIGH 81% HIGH 83%
KAND HIGH 94% HIGH 100% MED 75% HIGH 83%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLASH FLOOD WATCH UNTIL 10 AM EST THIS MORNING FOR GAZ010-017-
018-026-028-029.
NC...FLASH FLOOD WATCH UNTIL 10 AM EST THIS MORNING FOR NCZ033-
048>053-058-059-062>065-501>510.
SC...FLASH FLOOD WATCH UNTIL 10 AM EST THIS MORNING FOR SCZ001>007-
010-011.
&&
$$
SYNOPSIS...JPT
NEAR TERM...JAT/NED/WIMBERLEY
SHORT TERM...HG
LONG TERM...JPT
AVIATION...JAT
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1145 PM CST WED NOV 18 2015
.UPDATE...
UPDATED TO INCLUDE 06Z AVIATION DISCUSSION BELOW.
&&
.PREV DISCUSSION... /ISSUED 845 PM CST WED NOV 18 2015/
DISCUSSION...
CLEAR SKIES PREVAIL ACROSS THE MIDSOUTH. A WEAK COLD FRONT IS
APPROACHING FROM THE NORTHWEST WHILE WEAK HIGH PRESSURE SITS OVER
THE LOWER MISSISSIPPI VALLEY. THE PRESSURE GRADIENT IS WEAK ACROSS
NORTHEAST MISSISSIPPI WHERE SKIES CLEARED OUT LATE. FOG IS
ALREADY DEVELOPING ACROSS MONROE COUNTY AND POINTS SOUTHEAST.
LATEST HRRR SHOWS FOG SPREADING ACROSS NORTHEAST MISSISSIPPI
OVERNIGHT. ADDED AREAS OF FOG TO THE FORECAST AND WILL NEED TO
MONITOR FOR A POSSIBLE DENSE FOG ADVISORY. THE PRESSURE GRADIENT
IS A LITTLE STRONGER OVER THE REMAINDER OF THE AREA...THANKS TO
THE APPROACHING FRONT...WHICH SHOULD HELP KEEP A LIGHT SOUTHWEST
WIND GOING AND LIMIT FOG POTENTIAL. OTRW FORECAST IS ON TRACK.
UPDATE ALREADY OUT.
SJM
&&
.PREV DISCUSSION... /ISSUED 259 PM CST WED NOV 18 2015/
SKIES REMAIN CLOUDY OVER EASTERN SECTIONS OF THE FORECAST AREA
WITH MOSTLY SUNNY SKIES ELSEWHERE. TEMPERATURES THIS AFTERNOON
RANGE FROM THE MID 50S TO MID 60S. THE CLOUDS OVER EASTERN
SECTIONS OF THE FORECAST AREA WILL MOVE OUT THIS EVENING LEAVING
MOSTLY CLEAR TONIGHT. WINDS SHOULD NOT GO CALM OVERNIGHT SO IT
DOES NOT APPEAR THAT MUCH FOG WILL DEVELOP OVERNIGHT. TEMPERATURES
WILL COOL DOWN TO NEAR NORMAL LEVELS WITH LOWS THURSDAY MORNING IN
THE LOW TO MID 40S.
A SECOND COLD FRONT WILL PUSH THROUGH THE REGION ON THURSDAY. THE
AIR AHEAD OF THIS FRONT IS DRIER THAN THE FIRST FRONT SO NO RAIN
IS EXPECTED WITH THIS FRONT. TEMPERATURES WILL BE FAIRLY MILD
FOR MID-NOVEMBER WITH HIGHS IN THE UPPER 50S TO MID 60S. HIGH
PRESSURE WILL SETTLE INTO THE REGION THURSDAY NIGHT BRINGING
COLDER AIR INTO THE FORECAST AREA. LOWS FRIDAY MORNING WILL RANGE
FROM THE MID 30S TO LOWER 40S. HIGH PRESSURE WILL REMAIN NEAR THE
REGION ON FRIDAY WITH DRY WEATHER AND NEAR NORMAL TEMPERATURES.
BY FRIDAY NIGHT...ANOTHER COLD FRONT WILL MOVE INTO THE REGION BY
EARLY SATURDAY MORNING. THERE WILL BE SOME MOISTURE AHEAD OF THE
FRONT SO THERE COULD BE SOME SHOWERS LATE FRIDAY NIGHT OVER
NORTHWEST SECTIONS OF THE FORECAST AREA. AS THE FRONT MOVES
THROUGH THE REMAINDER OF THE FORECAST AREA ON SATURDAY MORE
SHOWERS WILL BE POSSIBLE MAINLY OVER NORTHERN SECTIONS.
TEMPERATURES WILL TURN COLDER BEHIND THE FRONT WITH HIGHS ON
SATURDAY IN THE UPPER 40S TO AROUND 60 DEGREES.
HIGH PRESSURE WILL BUILD INTO THE REGION SATURDAY NIGHT. THIS WILL
ALLOW TEMPERATURES TO DROP BELOW FREEZING OVER MUCH OF THE
FORECAST AREA SO THIS WILL LIKELY BE THE FIRST FREEZE FOR A LOT OF
THE AREA THAT DID NOT SEE BELOW FREEZING TEMPERATURES LAST
WEEKEND. HIGH PRESSURE WILL REMAIN OVER THE REGION ON SUNDAY
KEEPING THINGS UNSEASONABLY COOL WITH HIGHS MAINLY IN THE 40S.
SUNDAY NIGHT WILL BE ANOTHER CHILLY NIGHT WITH MOST LOCATIONS
SEEING TEMPERATURES NEAR OR BELOW FREEZING.
BY MONDAY...THE SURFACE HIGH WILL BE EAST OF THE REGION. THIS WILL
ALLOW WINDS TO SHIFT TO THE SOUTH AND BRING MILDER AIR INTO THE
FORECAST AREA. THIS WILL START A WARMING TREND WHICH WILL GO FROM
MONDAY THROUGH NEXT WEDNESDAY. A WEAK FRONTAL BOUNDARY WILL MOVE
INTO NORTHERN ARKANSAS NEXT WEDNESDAY WHICH COULD MEAN SOME RAIN
SHOWERS OVER WESTERN SECTIONS OF THE FORECAST AREA.
ARS
&&
.AVIATION...
06Z TAFS
VFR CONDITIONS WILL PREVAIL ACROSS THE AREA...EXCEPT AT TUP WHERE
DENSE FOG WILL BE AN ISSUE OVERNIGHT. LIFR/IFR VSBYS ARE EXPECTED
AS WINDS GO CALM. ELSEWHERE...WINDS SHOULD REMAIN FROM SOUTHWEST
AROUND 3 TO 5 KTS UNDER CLEAR SKIES.
WINDS WILL SHIFT NORTHWEST AND INCREASE TO AROUND 10 KTS AT ALL
SITES AFTER 19/18Z AS A DRY COLD FRONT MOVES THROUGH. WINDS WILL
RELAX TO 6 KTS OR LESS AFTER SUNDOWN.
AC3
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...DENSE FOG ADVISORY UNTIL 9 AM CST THURSDAY FOR ALCORN-CALHOUN-
CHICKASAW-ITAWAMBA-LEE MS-MONROE-PONTOTOC-PRENTISS-TIPPAH-
TISHOMINGO-UNION.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
339 AM CST THU NOV 19 2015
.SHORT TERM (TODAY THROUGH FRIDAY)...LIGHT NORTHEAST WINDS AND
NEAR ZERO TEMP/DEWPOINT SPREAD WILL LEAD TO A BRIEF POTENTIAL FOR
FOG OVER THE COASTAL PLAINS EARLY THIS MORNING. FOG HAS BEEN
REPORTED AT PORT LAVACA IN THE PAST HOUR. ONLY MODEL INDICATING
A STRONG INDICATOR FOR FOG IS THE LATEST RAP MODEL. WILL HAVE TO
WATCH TRENDS TO SEE IF FOG BECOMES DENSE OVER THE NEXT COUPLE OF
HOURS.
OTHERWISE...ANOTHER BENIGN WEATHER DAY IS EXPECTED. SURFACE HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL BUILD EASTWARD INTO THE
MID MISSISSIPPI RIVER VALLEY TODAY. WINDS WILL INCREASE FROM THE
EAST-NORTHEAST LATER TODAY. HIGH TEMPERATURES WILL BE NEAR OR
SLIGHTLY WARMER THAN YESTERDAY.
LOW LEVEL FLOW WILL VEER TO EAST-SOUTHEAST LATER TONIGHT AS LOW
PRESSURE DEEPENS LEE OF THE CENTRAL ROCKIES. LOW CLOUDS ARE
EXPECTED TO RETURN ALONG THE RIO GRANDE INTO THE BRUSH COUNTRY
LATE TONIGHT. LOW LEVEL FLOW WILL BECOME SOUTHERLY FRIDAY WITH
MOISTURE STEADILY INCREASING WITH MOSTLY CLOUDY SKIES EXPECTED.
WEAK ISENTROPIC LIFT WILL LEAD TO A SLIGHT CHANCE OF LIGHT RAIN
OVER THE COASTAL WATERS INTO THE COASTAL BEND BY THE AFTERNOON.
WENT NEAR OR SLIGHTLY BELOW COOLER NAM GUIDANCE FOR HIGHS.
&&
.MARINE...EAST-NORTHEAST FLOW IS EXPECTED TO INCREASE BY THIS
AFTERNOON OVER THE OFFSHORE WATERS TO SCEC LEVELS AND REMAIN
AT THIS STRENGTH THROUGH THE NIGHT. SWELLS OF 4 TO 5 FEET WITH
PERIOD OF 8 SECONDS ALONG WITH EAST-NORTHEAST WINDS WILL KEEP
A MODERATE RISK OF RIP CURRENTS ALONG THE COAST.
&&
.LONG TERM (FRIDAY NIGHT THROUGH THANKSGIVING DAY)...CHANCES FOR
RAIN INCREASE OUT AHEAD OF A SIGNIFICANT COLD FRONT DUE TO MOVE
THROUGH SOUTH TEXAS SATURDAY MORNING. EXPECT SCATTERED
SHOWERS...WITH BETTER CHANCES OVER THE MIDDLE TEXAS COAST WHERE LOW
LEVEL MOISTURE WILL HAVE A BETTER CHANCE AT POOLING BEFORE FROPA.
HIGHS ON SATURDAY WILL OCCUR IMMEDIATELY BEFORE THE FRONT
PASSES...WITH TEMPERATURES FALLING QUICKLY BEHIND THE FRONT. WINDS
WILL ALSO PICK UP SUBSTANTIALLY BEHIND THE FRONT...WITH SMALL CRAFT
ADVISORY CONDITIONS EASILY MET FROM FROPA ALL THE WAY THROUGH EARLY
SUNDAY. CAA WILL KEEP TEMPERATURES IN THE 50S ON SUNDAY...AND
READINGS WILL DIP INTO THE 40S AWAY FROM THE COAST MONDAY MORNING AS
HIGH PRESSURE BUILDS INTO THE REGION.
HIGH PRESSURE WILL BEGIN TO SLIDE OFF TO THE EAST LATE
MONDAY...INITIATING RETURN FLOW ALONG THE COASTAL BEND. A FEATURE OF
INTEREST WILL BE MOISTURE FROM AN EASTERN PACIFIC TROPICAL
SYSTEM...AND MEDIUM RANGE MODELS DISAGREE ON HOW MUCH OF THAT WILL
GET CAUGHT UP IN SOUTHWEST FLOW ALOFT. FOR NOW WILL FOLLOW A MIDDLE
ROAD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 81 61 77 67 70 / 0 0 20 40 50
VICTORIA 78 52 74 60 65 / 0 0 10 40 50
LAREDO 83 62 78 65 66 / 0 10 10 20 50
ALICE 82 58 78 65 68 / 0 0 20 30 50
ROCKPORT 80 62 76 66 70 / 0 0 20 40 50
COTULLA 81 56 76 62 64 / 0 0 10 20 50
KINGSVILLE 82 61 78 66 70 / 0 0 20 30 50
NAVY CORPUS 79 64 76 68 71 / 0 0 20 40 50
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TMT/89...SHORT TERM
JV/71...LONG TERM
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1103 AM EST THU NOV 19 2015
.UPDATE...
15Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN AMPLIFIED UPPER LEVEL
PATTERN IN PLACE OVER THE CONUS...HIGHLIGHTED BY A BROAD
NEGATIVELY-TILTED LONGWAVE TROUGH. THIS TROUGH IS ANCHORED BY A
CLOSED LOW FEATURE SPINNING OVER THE UPPER MIDWEST. MOISTURE PLUME
ASSOCIATED WITH THE SOUTHERN STREAM JET IS WELL DEFINED ON WV
IMAGERY CROSSING THE GULF OF MEXICO AND OVER THE FLORIDA
PENINSULA. IN THE PAST FEW HOURS HAVE SEEN THE DEVELOPMENT OF
LEAF-CLOUD FEATURE OVER THE FLORIDA PANHANDLE/NORTH-CENTRAL GULF
OF MEXICO WITHIN THIS MOISTURE PLUME. THIS FEATURE APPEARS TO BE
ASSOCIATED WITH THE INTERACTION OF PASSING SHORTWAVE ENERGY (MOST
DEFINED ABOVE 500MB) WITH THE LOWER LEVEL FRONTAL BOUNDARY. THIS
CYCLOGENESIS IS NOT BEING REPRESENTED WELL IN THE ENSEMBLE
GUIDANCE AND HENCE THE MODELS ARE GENERALLY NOT HANDLING THE
HIGHER COVERAGE OF CONVECTION OVER THE NORTHEAST GULF VERY WELL.
AS THIS FRONTAL WAVE MOVES EAST IT HAS BECOME OBVIOUS THAT A
DEVIATION FROM THE GUIDANCE SOLUTIONS IS NECESSARY AND HAVE MADE
SOME SIGNIFICANT FORECAST UPDATES TO OUR NORTHERN ZONES IN TERMS
OF RAINFALL POPS AND QPF THROUGH THE REMAINDER OF THE DAY AS IT
LOOKS TO BE RATHER WET TO THE NORTH OF BROOKSVILLE.
WATCHING NEW GUIDANCE ARRIVAL AND RADAR/WV TRENDS CLOSELY TO
DETERMINE IF HIGHER POPS WILL BE REQUIRED LATER TODAY FURTHER
SOUTH...DOWN INTO SUMTER/HERNANDO/PASCO...MAYBE EVEN THE TAMPA BAY
AREA. JUST HOW FAR SOUTH THE MORE ORGANIZED CONVECTION EXPANDS
WILL BE DEPENDENT ON THE SPEED THAT THE FRONTAL WAVE PASSES BY.
THE SLOWER THE PASSAGE THE FURTHER SOUTH THE FRONT WILL HAVE
PROGRESSED. AT THE SAME TIME...ANY SURFACE LOW DEVELOPMENT WILL
SLOW THE SOUTHWARD PROGRESSION OF THE BOUNDARY. SO...ITS A
DIFFICULT FORECAST SOUTH OF BROOKSVILLE THROUGH 00Z.
SOUTH OF TAMPA BAY...MAINLY LOOKING FOR THE DEVELOPMENT OF MORE
DIURNAL TYPE SCT SHOWERS INTO THE LATER AFTERNOON/EVENING
HOURS...BUT NO ORGANIZED OR LONG LASTING TYPE OF RAINFALL THROUGH
THE REST OF THE DAY.
TONIGHT...
SHORTWAVE ENERGY PASSES OFF TO THE NORTHEAST WITH TIME ALLOWING
WHATEVER FRONTAL WAVE THERE IS TO EXIT AND SWING THE COLD FRONT
DOWN THE PENINSULA. THIS PROGRESSION WILL SLOWLY DECREASE RAIN
CHANCES TO THE NORTH OF THE 1-4 CORRIDOR...WHILE AT LEAST
SCATTERED SHOWERS CONTINUE IN THE FORECAST FOR THE SOUTHERN HALF
OF THE AREA. BY DAWN THE FRONT LOOKS TO HAVE BECOME QUASI-
STATIONARY OVER SOUTH FLORIDA. ENOUGH DRY AIR ALOFT LOOKS TO HAVE
ADVECTED SOUTHWARD TO BASICALLY END RAIN CHANCES NORTH OF TAMPA
BAY FOR FRIDAY MORNING...BUT WILL BE INCREASING POPS THE FURTHER
SOUTH ONE TRAVELS FROM THE I-4 CORRIDOR...IN CLOSER PROXIMITY TO
THE STALLED FRONTAL FOCUS.
&&
.AVIATION...
VFR/MVFR CIGS ACROSS THE REGION LATE THIS MORNING. MOST OF THE
RAINFALL IS NORTH OF THE TERMINALS. SOME INDICATIONS THAT MORE
NUMEROUS SHOWERS MAY BECOME NECESSARY FOR KTPA/KPIE LATER
TODAY...AND WILL BE MONITORING RADAR TRENDS CLOSELY.
TONIGHT...PERIOD OF MVFR CIGS/VIS LOOK PROBABLE FOR ALL TERMINALS
AS A WEAK COLD FRONT SETTLES SOUTH ACROSS THE REGION. A PERIOD OF
IFR IS NOT OUT OF THE QUESTION FOR KLAL/KPGD...BUT WILL KEEP OUT
OF CURRENT TAF PACKAGE UNTIL CONFIDENCE INCREASES.
&&
.MARINE...
A WEAKENING COLD FRONT WILL APPROACH THE WATERS FROM THE
NORTHWEST TODAY AND SETTLE THROUGH THE EASTERN GULF OF MEXICO
TONIGHT. THIS FRONT WILL STALL OVER SOUTH FLORIDA DURING FRIDAY.
A WEAK WAVE OF LOW PRESSURE NOW LOOKS TO RIDE ALONG THIS FRONT
AND THROUGH THE EASTERN GULF DURING THE UPCOMING WEEKEND. IF THIS
TREND CONTINUES...THE CHANCES FOR MORE WIDESPREAD RAINFALL
SATURDAY AND SUNDAY WILL BE INCREASING IN FUTURE FORECASTS. HIGH
PRESSURE WILL THEN BUILD IN FROM THE NORTH IN THE WAKE OF THIS
LOW LATE SUNDAY AND THROUGH THE EARLY PORTION OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 83 71 82 67 / 40 40 20 20
FMY 86 72 84 68 / 40 50 50 40
GIF 84 69 80 65 / 60 50 20 20
SRQ 83 71 83 69 / 40 40 20 30
BKV 84 67 81 64 / 50 40 20 20
SPG 83 71 81 70 / 40 40 20 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...BEACH HAZARDS STATEMENT UNTIL 10 PM EST THIS EVENING FOR
COASTAL SARASOTA-PINELLAS.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION/MARINE...MROCZKA
AREA FORECAST DISCUSSION
NWS GOODLAND KS
418 AM MST THU NOV 19 2015
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 206 AM MST THU NOV 19 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOWS LONG FETCH OF NW
FLOW EXTENDING FROM THE PACIFIC NW ACROSS THE CENTRAL ROCKIES INTO
THE THE PLAINS...WITH SARGE TROUGH ALONG THE MISSISSIPPI RIVER
VALLEY. AT THE SURFACE HIGH PRESSURE IS IN PLACE.
SNOW PACK CONTINUES TO BE A CONSIDERATION THROUGH AT LEAST THE SHORT
RANGE PERIODS FOR T/TD...AND ADJUSTMENTS WERE MADE ACCORDINGLY.
TODAY-TONIGHT...PASSING HIGH CLOUDS ASSOCIATED WITH WEAK RIPPLES
WITHIN NW FLOW ALOFT WILL CONTINUE THROUGH TONIGHT. OTHERWISE DRY
CONDITIONS WILL PERSIST. A COOLER AIR MASS WILL REMAIN IN PLACE
AND TEMPERATURES WILL BE AT LEAST 5-15F COOLER THAN YESTERDAY
ESPECIALLY IF WE SEE MORE EXTENSIVE/OPAQUE CLOUD COVER.
FRIDAY-FRIDAY NIGHT...A STRONGER SHORTWAVE TROUGH/CLIPPER EMBEDDED
WITH NW FLOW WILL MOVE THROUGH THE REGION ALONG WITH ANOTHER COLD
FRONT (PASSING LATE AFTERNOON). MOISTURE ADVECTION IS LIMITED DUE TO
THE TRAJECTORY/TRACK OF THIS SYSTEM...HOWEVER THERE WILL BE ENOUGH
FORCING TO SUPPORT A FEW RAIN/SNOW SHOWERS OR SPRINKLES/FLURRIES
DURING THESE PERIODS. MODELS SHOWS VERY STRONG GRADIENT
ALONG/BEHIND FRONT HIGHLIGHTED BY 8-10 MB 3HR PRESSURE RISES (10-15
MB 6 HR PRESSURE RISES). ITS HARD TO TELL HOW DEEP WE WILL MIX AS
THERE COULD BE EXTENSIVE CLOUD COVER AND POSSIBLE INVERSION ABOVE
LINGERING SNOW PACK. IF WE WERE TO MIX TO 850 MB WE COULD SEE WINDS
45-50 MPH. WINDS ABOVE THIS LAYER ARE EVEN HIGHER...SO THIS WILL
NEED TO BE WATCHED IN THE EVENT SHOWERS HELP MIXING AND CREATE
ISOLATED 60 MPH DOWNBURST. INCREASING WAA AHEAD OF THIS FRONT
SHOULD ALLOW SOME LOCATIONS TO WARM INTO THE MID 50S BEFORE
TEMPERATURES START DECREASING IN THE AFTERNOON.
SATURDAY-SATURDAY NIGHT...ANOTHER SHORTWAVE TROUGH IS ADVERTISED TO
PASS THROUGH THE NORTHERN PLAINS...HOWEVER THIS FEATURE IS NOT QUITE
AS STRONG...AND MOISTURE PROFILES ARE EVEN LESS FAVORABLE. DRY
CONDITIONS SHOULD BE EXPECTED THOUGH THESE PERIODS. THIS SHORTWAVE
WILL ALSO HELP REINFORCE THE COOLER POST FRONT AIR MASS...SO HIGHS
IN THE 30S ARE EXPECTED ACROSS OUR CWA AND I COULD SEE SOME
LOCATIONS WITH HIGHS AROUND 32.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 206 AM MST THU NOV 19 2015
NORTHWEST FLOW ALOFT REMAINS OVER THE REGION ON SUNDAY BEFORE AN
UPPER RIDGE OVER THE WESTERN CONUS FLATTENS OUT OVER THE HIGH PLAINS
ON MONDAY AND TUESDAY. THIS PATTERN WILL BRING DRY CONDITIONS AND
WARMER TEMPERATURES TO THE FORECAST THROUGH EARLY NEXT WEEK.
GUIDANCE IS SHOWING AN UPPER LOW MOVING OVER THE PACIFIC NORTHWEST
TUESDAY NIGHT. DRY CONDITIONS CONTINUE FOR THE AREA ON WEDNESDAY
AHEAD OF THIS SYSTEM AS IT TRAVELS EASTWARD TOWARDS THE PLAINS WITH
THE ASSOCIATED COLD FRONT LOOKING TO PASS THROUGH THE REGION BY
THURSDAY. COULD SEE PRECIP CHANCES LATER NEXT WEEK WITH THIS SYSTEM.
EXPECT TEMPERATURES TO WARM INTO EARLY NEXT WEEK WITH HIGHS IN THE
40S ON SUNDAY GRADUALLY INCREASING INTO THE 50S BY TUESDAY BEFORE
COOLING INTO THE UPPER 40S TO MID 50S FOR WEDNESDAY. CONTINUED TO
KEEP THE COOLER TEMPERATURES IN AREAS WHERE SNOWPACK MAY STILL BE
PRESENT. HOWEVER...SUSPECT MELTING WILL OCCUR BEFORE THE END OF THIS
PERIOD. LOWS WILL GENERALLY BE IN THE 20S. THE REGION COULD SEE A
BLAST OF COLD AIR TOWARDS THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 417 AM MST THU NOV 19 2015
VFR CONDITIONS SHOULD CONTINUE THROUGH THE TAF PERIOD. 9-10 KFT
AGL CLOUD DECK OVERSPREADING THE REGION BY TONIGHT AS UPPER LEVEL
DISTURBANCE APPROACHES. SURFACE LOW BUILDING OVER EASTERN
COLORADO WILL CONTINUE TO MOVE EASTWARD AND WINDS WILL SHIFT FROM
THE W-SW TO THE SOUTH. PREVAILING WINDS WILL REMAIN LESS THAN
12KT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1017 AM EST THU NOV 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER SOUTHEAST CANADA WILL SLIDE EAST TODAY AS A
COLD FRONT APPROACHES FROM THE WEST. THE FRONT CROSSES THE AREA
THIS EVENING...WITH HIGH PRESSURE BUILDING IN FRIDAY AND
SATURDAY. A DRY COLD FRONT WILL MOVE ACROSS THE REGION SATURDAY
NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST GOES WATER VAPOR IMAGERY DEPICTS MOISTURE PLUME LIFTING ALONG
THE SE COASTAL PLAIN INTO THE LOCAL AREA DOWNSTREAM OF A POTENT NRN
STREAM CLOSED LOW OVER SOUTH CENTRAL CANADA. AT THE SFC...COLD FRONT
HAS LOCATED OVER THE CENTRAL APPALACHIANS WITH A WARM FRONT OVER NC.
SHOWER COVERAGE HAS DIMINISHED THIS MORNING...WITH THE BEST COVERAGE
OVER SOUTHERN VA AND NE NC. ELSEWHERE...SHOWERS HAVE BECOME MORE
SCATTERED IN NATURE. FEW LIGHTNING STRIKES WERE OBSERVED OVER
MECKLENBURG COUNTY WHERE RAP GUIDANCE INDICATES SLIGHTLY STEEPER MID
LEVEL LAPSE RATES TO GO ALONG WITH <250 J/KG MUCAPE...BUT HAS SINCE
DIMINISHED. DO NOT ANTICIPATE MORE THAN ISOLATED/EMBEDDED RUMBLE OF
THUNDER BASED ON VERY LITTLE INSTABILITY...BUT WILL MAINTAIN SLIGHT
CHANCE THUNDER WORDING IN FORECAST.
FOR THE REST OF THE DAY...SHORTWAVE ENERGY PUSHES OFFSHORE AS THE
COLD FRONT SLOWLY CROSSES THE REGION. SWLY FLOW ALOFT WILL
PERSIST...BUT BEST MOISTURE PUSHES EAST OF INTERSTATE 95 BY EARLY
AFTERNOON LEAVING ONLY SCATTERED SHOWERS OVER THE PIEDMONT INTO
CENTRAL VA. ISENTROPIC LIFT INDICATED IN NAM12 THETA SURFACES WILL
LIKELY RESULT IN INCREASING COVERAGE ALONG THE COAST AS THE SHOWERS
FROM NC LIFT INTO THE ERN AREA. WILL MAINTAIN LIKELY TO CATEGORICAL
POPS EAST OF INTERSTATE 95. ADDITIONAL QPF AMOUNTS WILL RANGE FROM A
LESS THAN QUARTER OF AN INCH WEST TO HALF AN INCH EAST. HIGHEST
AMOUNTS IN THE SOUTHEAST WHERE AREAS COULD SEE UP TO AN INCH. HIGHS
GENERALLY IN THE UPPER 60S TO LOW 70S. WILL BEGIN TO SEE BREAKS IN
THE CLOUDS LATE TODAY OVER THE PIEDMONT...PERHAPS INTO CENTRAL VA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
COLD FRONT PROGGED INVOF CHES BAY BY 00Z FRI THEN QUICKLY MOVES
OFFSHORE BY 06Z. THUS...SLGT CHANCE-CHANCE EVENING POPS WILL BE
MAINTAINED MAINLY EAST OF I-95 TO CHES BAY...WITH LIKELY POPS
NEAR THE COAST. ENOUGH MOISTURE NOTED TO KEEP SLIGHT CHANCE POPS
NEAR THE COAST AFTER MIDNIGHT. OTHERWISE...TSCTNS SHOW COLUMN
DRYING WHICH SHOULD RESULT IN DECREASING CLOUDINESS WEST OF THE
BAY. CAA SETS IN AS WINDS SHIFT TO THE NW. LOWS DROP BACK INTO THE
40S WRN HALF OF FA...50-55 ALONG THE COAST.
HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST FRI INTO SAT.
STRONG SUBSIDENCE RESULTS IN MAINLY CLEAR SKIES ALONG WITH A RETURN
TO NEAR NORMAL TEMPS. RATHER BREEZY FRI...ESPECIALLY ALONG THE
COAST. HIGHS FRI UPPER 50S TO LOWER 60S. LOWS FRI NIGHT LOWER 30S
NW TO LOWER 40S SERN COASTAL AREAS. HIGHS SAT IN THE MID-UPPER
50S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
OVERALL HAVE GOOD MODEL AGREEMENT FROM SUNDAY THROUGH
NEXT WEDNESDAY AS ONE COLD FRONT SWEEPS ACROSS THE MID ATLANTIC
REGION LATE SATURDAY NIGHT AND THEN HIGH PRESSURE MOVES INTO THE
AREA AND LINGERS THROUGH MID WEEK. THE 12Z GFS WAS MORE AGGRESSIVE
PUSHING THE FRONT OFF THE COAST AND ALSO IS A LITTLE COLDER WITH
850 TEMPS FALLING TO AROUND -10C AROUND 06Z MONDAY BEFORE THE AIR
MASS MODIFIES. THE 12Z ECMWF SLOWS THE PUSH OF THE COLDER AIR AND
ACTUALLY KEEPS IT FURTHER TO THE NORTH AND ALLOWS FOR MORE NELY
FLOW. IN SPITE OF THESE DIFFERENCES...THE FORECAST GENERALLY SHOWS
DRY AND COOL WEATHER FROM SUNDAY INTO WEDNESDAY. THE COLD FRONT IS
EXPECTED TO GO THROUGH DRY AS THE INITIAL BOUNDARY THAT GOES
THROUGH ON THURSDAY SUPPRESSES THE GULF MOISTURE AND WITH THE
WEST TO EAST MOVEMENT OF THE FRONT...ANY MOISTURE SHOULD BE RUNG
OUT AS THE BOUNDARY CROSSES THE MOUNTAINS. EXPECT A COLDER AND
WINDIER DAY ON SUNDAY AS THE TIGHTENING PRESSURE GRADIENT AND COLD
AIR ALOFT ALLOW FOR GOOD MIXING. AFTER A COLD NIGHT SUNDAY
NIGHT (WHICH COULD SEE WIDESPREAD FREEZING TEMPS)...EXPECT TO SEE
A GRADUAL WARMING TREND AS THE SFC HIGH SLOWLY MOVES OFF TO THE
EAST AND THE COLD AIR RETREATS BACK NORTH.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
AREA OF RA PROGRESSING TO THE CST ATTM. PDS OF MNLY MVFR
CIGS/VSBYS W/ THIS RA. ADDITIONAL SHRAS BACK TO THE WSW BEHIND
THIS AREA. WILL HAVE IFR/LO END MVFR CONDS AFT THIS BAND OF RA
EXITS THE CST INTO THE AFTN (EVE TWD THE CST). VERY LO PROB FOR
THUNDER (PRIMARILY NR THE CST) LATE MRNG INTO MID AFTN. SE TO S
WNDS TO BECOME GUSTY TO 20-30 KT BEFORE BECOMING SW THIS EVE.
CDFNT PUSHES OFF THE CST TNGT. HI PRES THEN BUILDS IN FM THE W
FRI. THIS WILL RESULT IN DRY CONDS WITH A GUSTY N
WIND...DIMINISHING FRI AFTN. LIGHT WINDS FRI NIGHT INTO MID DAY
SAT. ANOTHER FRONT BRINGS STRONGER N-NW WINDS INTO SUN ALTHOUGH IT
LOOKS TO STAY DRY.
&&
.MARINE...
SE WNDS STEADILY INCRSG ATTM...STILL MNLY BLO SCA BUT W/ CDFNT
APPROACHING FM W AND PRES GRADIENT TIGHTEN UP A BIT MORE...CONTD
STRENGTHENING XPCD. THE PERSISTENT ESE FLO OVR THE WRN ATLC HAS
KICKED SEAS UP TO 5 TO 7 FT IN THE CSTL WTRS AND 3 TO 4 FT IN THE
LWR BAY. GUSTY SE WNDS CONT INTO THIS AFTN...THEN THE CDFNT
CROSSES THE WTRS THIS EVE W/ A BRIEF 4 TO 8 HR WEAKENING OF THE
WINDS BEFORE THE COLDER AIR ALOFT HITS THE WTRS AFT 06Z/20 W/ A
NNW SURGE OF 20 TO 30 KT (MAYBE BRIEF GALE GUSTS...ESP ON THE OCN
CENTERED ON 12Z/20). XPCG THIS SURGE TO LINGER INTO FRIDAY
AFTERNOON BEFORE WEAKENING AS SFC HI BUILDS INTO THE RGN FM THE W.
FOR THE WEEKEND...SHOULD SEE BENIGN CONDITIONS ON SATURDAY AS HIGH
PRESSURE IS IN PLACE AND THE WIND WEAKENS TO 5 TO 10 KT...EXPECT
THE SEAS TO GRADUALLY DIMINISH AS WELL. THE FLOW WILL TURN SW ON
SATURDAY NIGHT AS ANOTHER COLD FRONT SWEEPS THROUGH THE AREA. THE
MODELS SHOW ANOTHER STRONG SURGE OF COLD AIR BEHIND THIS FRONT SO
EXPECT THE WIND AND SEAS TO PICK UP ONCE AGAIN WITH SCA EXPECTED.
BY EARLY NEXT WEEK...HIGH PRESSURE ONCE AGAIN BUILDS OVER THE
WATERS AND CONDITIONS SHOULD IMPROVE ONCE AGAIN.
&&
.TIDES/COASTAL FLOODING...
A COLD FRONT APPROACHES FM THE W THROUGH MIDDAY...AND SLOLY
PUSHES OFFSHORE THIS EVE. POSITIVE TIDAL ANOMALIES STILL ON TRACK
TO BE 1 TO 1.5 FT OVER THE MIDDLE BAY (ESP ON THE LWR MD ERN
SHORE). WATER LEVELS ARE EXPECTED TO COME CLOSE TO MINOR FLOODING
THRESHOLDS ALONG THE BAY SIDE OF THE LOWER MD ERN SHORE AS WELL AS
TIDAL POTOMAC LOCATIONS OF THE NORTHERN NECK CONCURRENT WITH HIGH
TIDE CYCLES INTO TNGT.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO NOON EST FRIDAY FOR
ANZ635>638.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ650-652-
654-656-658.
&&
$$
SYNOPSIS...MAS
NEAR TERM...MAS/SAM
SHORT TERM...MAS/MPR
LONG TERM...ESS
AVIATION...ALB/LKB/DAP
MARINE...ALB/ESS
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
954 AM EST THU NOV 19 2015
.SYNOPSIS...
THIS AFTERNOON WILL BE MILD AND SHOWERY, JUST AHEAD OF AN
APPROACHING COLD FRONT. ONCE THE FRONT PASSES THE REGION THIS
EVENING, DRIER WEATHER, ALONG WITH CHILLIER, MORE SEASONABLE
TEMPERATURES, WILL FOLLOW OVERNIGHT AND FRIDAY. OUR NEXT CHANCE
FOR SHOWERS IS EXPECTED FOR LATER SATURDAY, AS ANOTHER COLD FRONT
MOVES IN FROM THE NORTHWEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR SHOWS PATCHY AREAS OF RAIN SHOWERS WORKING NORTH TO
NORTHEAST ACROSS CENTRAL NY AND NORTHEAST PA. MODELS AND SPC
MESOANALYSIS PAGE SHOW A LOW-LEVEL JET FROM 50-65 KNOTS ACROSS
CENTRAL AND WESTERN NY AT THIS TIME. THIS LOW-LEVEL JET IS
PROGGED TO TRACK EAST REACHING THE I-81 CORRIDOR BY 18Z AND ERN
NY/WRN NEW ENGLAND BY 00Z AS A CD FRNT PUSHES INTO C NY.
STRONG LOW-LEVEL MOISTURE ADVECTION WILL CONTINUE TO LEAD TO
DESTABLIZATION FORMING SHOWERS AS IT WORKS E. THERE WAS A
TOPOGRAPHICAL COMPONENT TO THE PRECIPITATION AS UPSLOPE AREAS ON
THE STRG SOUTHERLY WINDS WERE SEEING MORE PRECIPITATION COVERAGE
THAN DOWNSLOPE AREAS. HENCE SHOWERS WERE MOST EXTENSIVE IN PARTS
OF NE PA AND NRN NY. USED HRRR RADAR FIELDS TO POPULATE POP GRIDS
THROUGH THE AFTERNOON WHICH ARE IN GOOD AGREEMENT WITH ON-GOING
PRECIP AND TERRAIN EFFECTS.
MODEL SOUNDINGS INTO THE EARLY AFTERNOON SHOW STRONG WINDS OF ABT
50 KNOTS OR SO DOWN TO ABOUT 2000 FEET AGL...THEN THE WINDS
RAPIDLY WEAKEN TO THE SFC LAYER. IRIS MESONET OBS SHOW A FEW
STATIONS WITH GUSTS OVER 40 MPH WITH THE VAST MAJORITY OF STATIONS
IN THE 30S MPH INCLUDING OUR MAJOR AIRPORTS. HENCE IT WILL BE
WINDY BUT BELOW WIND ADVY CRITERIA. AS THE LLJ WORKS E THIS
AFTERNOON WINDS WILL SLACKEN. WILL ISSUE SPS TO COVER FOR OUR NRN
COUNTIES.
WATER VAPOR IMAGERY SHOWS A SHORT WAVE TROF AXIS FROM IA/IL TO THE
DEEP SOUTH WHICH WILL SWING NE LATER THIS AFTERNOON AND EVENING
AND RE-ORGANIZE PRECIP MAINLY E OF I-81 AS IT WORKS NE AHEAD OF
CD FRNT THAT REACHES THE I-81 CORRIDOR BY 00Z. HENCE HAVE CAT
POPS TRACKING NE ACRS NE PA TO CATSKILLS LATER TODAY AND THIS
EVENING.
AFTER THIS WAVE PASSES OVERNIGHT PRECIP WINDS DOWN AND A
SECONDARY CD FRNT MOVES THROUGH WITH A RETURN TO MORE SEASONALLY
CHILLY TEMPERATURES BY FRI AM.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
3 AM UPDATE... A RELATIVELY QUICK EXIT OF THE STEADIER RAINFALL IS
ANTICIPATED THIS EVENING, AS THE SURFACE FRONT SWEEPS TO OUR EAST.
BEHIND THE FRONT, DRY ADVECTION/SINKING MOTION SHOULD LEAD TO AT
LEAST PARTIAL CLEARING FOR MOST OF THE FORECAST AREA. LOWS BY
DAYBREAK SHOULD RANGE FROM THE MID 30S-LOWER 40S.
FRIDAY-SATURDAY LOOKS GENERALLY DRY, AS A SURFACE HIGH AND SHORT-
WAVE RIDGING ALOFT SLIDE ACROSS NY/PA. TEMPERATURES WILL BE
SEASONABLY CHILLY, WITH HIGHS BOTH DAYS MAINLY IN THE 40S, AND
LOWS FRIDAY NIGHT MOSTLY IN THE 20S.
OUR NEXT WEATHER MAKER, IN THE FORM OF ANOTHER COLD FRONTAL
BOUNDARY, WILL BRING A CHANCE OF SHOWERS BY SATURDAY EVENING, AS
IT MOVES IN FROM THE WEST. LATER SATURDAY NIGHT OR EARLY SUNDAY
MORNING, ENOUGH COLD AIR ADVECTION MAY DEVELOP BEHIND THIS SYSTEM,
TO BRING LAKE-EFFECT SNOW SHOWERS TO UPSTATE NY, PERHAPS
IMPACTING SOME OF OUR NORTHERN ZONES. AS FRONTAL TIMING, ALONG
WITH FLOW ORIENTATION AND THE DEGREE OF COOLING POST FRONTAL
PASSAGE, BECOME CLEARER IN THE COMING DAYS, FORECAST DETAILS WILL
ALSO GET FIRMED UP IN THIS REGARD.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
345 AM UPDATE... COLD CYCLONIC FLOW WILL BE WITH US TO START THE
PERIOD SUNDAY, WITH MODEL CONSENSUS 850 MB TEMPERATURES DIPPING
TO -10 TO -12C. THIS SHOULD BE SUFFICIENTLY COLD FOR LAKE-EFFECT
SNOW SHOWERS. EARLY INDICATIONS ARE THAT THE PREVAILING FLOW
DIRECTION WILL BE DUE WESTERLY, PROBABLY KEEPING THE MOST
PERSISTENT ACTIVITY JUST NORTH AND WELL WEST OF OUR FORECAST
AREA. AT THIS JUNCTURE, WE HAVE A CHANCE OF RAIN/SNOW SHOWERS FOR
OUR NORTHERN/FAR WESTERN ZONES, WITH LIKELY PROBABILITIES UP OVER
NORTHERN ONEIDA COUNTY. SOME ACCUMULATIONS ARE CERTAINLY
POSSIBLE, ESPECIALLY ACROSS THE HIGHER TERRAIN. ONCE SMALLER-SCALE
DETAILS, SUCH AS EXACT LOW-LEVEL WIND DIRECTIONS, BECOME MORE
CERTAIN, SO WILL THE POTENTIAL FOR ANY SNOW ACCUMULATIONS.
NEXT WEEK, THERE IS FAIRLY GOOD MODEL AGREEMENT THAT HEIGHTS WILL
RISE OVER TIME ACROSS THE EASTERN U.S., AS A DEEP TROUGH/CLOSED
LOW DIGS INTO THE INTERMOUNTAIN WEST. THIS EVOLUTION SHOULD LEAD
TO MODERATING TEMPERATURES, LIKELY REACHING LEVELS ABOVE NORMAL
AGAIN, AS WE HEAD TOWARDS THE THANKSGIVING HOLIDAY PERIOD.
FAST MOVING, NORTHERN STREAM UPPER WAVES, COULD BRING SOME
RESIDUAL RAIN/SNOW SHOWERS MONDAY INTO EARLY TUESDAY. OTHERWISE,
MUCH OF NEXT WEEK LOOKS DRY, UNDERNEATH A BUILDING RIDGE ALOFT (AS
ALLUDED TO ABOVE).
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
AN OCCLUDED FRONT IS SET TO CARRY WEST TO EAST ACROSS THE
TERMINALS THIS COMING AFTERNOON. WELL AHEAD OF IT...AN UPPER WAVE
WILL IS SPREADING SHOWERS OVER THE AREA. ALSO OCCURRING IN
ADVANCE OF THE FRONT...A STRONG SOUTHERLY 50-60 KT LOW LEVEL JET
WILL CONTINUE TO PRODUCE LOW LEVEL WIND SHEAR FOR ALL TERMINALS
UNTIL FRONTAL PASSAGE. CIG WILL BE MAINLY HIGHER END MVFR /EVEN
VFR KSYR/ AHEAD OF THE FRONT...THEN MOSTLY DIPPING TO FUEL ALT
CIGS AS THE FRONT NEARS. KBGM-KAVP WILL PROBABLY DIP INTO IFR CAT
AROUND FRONTAL PASSAGE. WINDS GENERALLY SE-SSW IN LOWER TEENS WITH
SOME GUSTS 20 KTS OR SO. SW TO W VEERING WILL OCCUR BEHIND THE
FRONT LATE AFTERNOON-EVENING AS WIND SPEED ALSO DIMINISHES.
.OUTLOOK...
FRIDAY-SATURDAY...VFR.
SAT NIGHT...COLD FRONTAL PASSAGE WITH RAIN SHOWERS CHANGING TO
SNOW SHOWERS...AND ASSOCIATED POSSIBLE RESTRICTIONS.
SUN THROUGH MON...RESTRICTIONS AT TIMES IN MIXED SHSN AND SHRA...MAINLY
CENTRAL NY TERMINALS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/MLJ
NEAR TERM...DJN
SHORT TERM...MLJ
LONG TERM...MLJ
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
932 AM EST THU NOV 19 2015
.SYNOPSIS...
A STORM SYSTEM WILL LIFT INTO HUDSON BAY AND PUSH A COLD FRONT
ACROSS OUR REGION TODAY. AHEAD OF THIS FRONT IT WILL BE WARM AND
WINDY WITH SOME SHOWERS...BUT MORE SEASONABLY COOL TEMPERATURES WILL
BUILD INTO THE REGION BEHIND THE FRONT TONIGHT AND FRIDAY. COLDER
WEATHER WILL RETURN THIS WEEKEND WITH SOME LAKE EFFECT SNOW SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
OTHER THAN THE WINDS...IT WILL BE UNSEASONABLY WARM THIS MORNING
WITH TEMPERATURES IN THE 60S IN MOST AREAS. THE LLJ AND A MID-LEVEL
DISTURBANCE WILL GENERATE LIFT AND AN AREA OF SHOWERS. CONSENSUS
QPF SUGGESTS THE STEADIEST SHOWERS WILL BE ACROSS THE EASTERN LAKE
ONTARIO REGION TODAY. QPF HAS BEEN OVERDONE WITH DOWNSLOPE DRYING
THE LIKELY CAUSE. BASED ON THIS HAVE ACCEPTED THE MODEL MEAN
POSITION...BUT HAVE REDUCED AMOUNTS.
THE HRRR AND OTHER HIGH RESOLUTION GUIDANCE ALSO DEVELOPS SOME
SHOWERS ALONG THE FRONT WHICH MAY BRING ANOTHER QUICK ROUND OF
SHOWERS TO AREAS NORTH OF I-90. THE COLD FRONT WILL ENTER WESTERN
NEW YORK AROUND NOON...AND SWEEP FROM W-E DURING THE AFTERNOON
HOURS. THIS WILL BRING COOLER (BUT NOT YET COLD) AIR INTO THE
REGION THIS AFTERNOON AND ALSO BRING AN END TO THE SHOWERS.
COLD AIR ADVECTION WILL CONTINUE TONIGHT FROM A MODERATE WSW FLOW.
THIS AIR MASS IS QUITE DRY WHICH SHOULD SUPPRESS LAKE EFFECT
ACTIVITY...HOWEVER WITH CONSENSUS 850MB TEMPERATURE FORECAST TO DROP
TO AROUND -7C THERE WILL BE QUITE A BIT OF LAKE INDUCED INSTABILITY.
THE MAJORITY OF HIGH RESOLUTION GUIDANCE DOES NOT FORECAST ANY LAKE
EFFECT RAIN OR SNOW SHOWERS...WITH THE RGEM GUIDANCE A NOTABLE
EXCEPTION. GIVEN THE DELTA T VALUES AND THE FAIRLY GOOD TRACK RECORD
OF THE RGEM GUIDANCE CHANCE POPS WILL BE INTRODUCED EAST OF LAKE
ERIE. ANY SHOWERS WOULD START OFF AS RAIN...BUT CHANGE OVER TO SNOW
LATE TONIGHT AS TEMPERATURES COOL. SPEAKING OF TEMPERATURES...NEW
GUIDANCE SUPPORTS COLDER LOW TEMPERATURES FOR TONIGHT...WITH MOST
AREAS EXPECTED TO DROP INTO THE 30S BY DAYBREAK FRIDAY MORNING.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
FRIDAY SURFACE HIGH PRESSURE WILL BULGE NORTHEASTWARD FROM THE LOWER
OHIO VALLEY...AND SPREAD FAIR WEATHER TO THE EASTERN GREAT LAKES
REGION. THERE MAY BE A LITTLE LINGERING LAKE EFFECT
PRECIPITATION EAST OF LAKE ERIE. WHILE TEMPERATURES AT 850 HPA (-6 TO
-8C) WILL BE COOL ENOUGH TO SUPPORT A LAKE EFFECT RESPONSE THE DRIER
AIR ASSOCIATED WITH THE SURFACE HIGH PRESSURE MAY BE JUST ENOUGH TO
PREVENT A BAND OF PRECIPITATION FROM FORMING. FOR NOW WILL CARRY A
LOW CHANCE POP FOR EAST OF LAKE ONTARIO THROUGH THE MORNING HOURS OF
FRIDAY.
THERE WILL REMAIN AN UPPER LEVEL TROUGH OVER THE REGION FRIDAY
MORNING...AND THIS FEATURE WITH ITS COOLER POOL OF AIR ALOFT MAY
ALSO ALLOW FOR SOME CLOUDS TO LINGER ACROSS THE REGION IN ADDITION
TO THE LAKE EFFECT CLOUDS. CLOUDS UNDER THE TROUGH WILL BE MOST
LIKELY TOWARDS THE EAST FOR THE FINGER LAKES AND EASTERN LAKE
ONTARIO REGION. AS THE UPPER LEVEL TROUGH LIFTS NORTHEASTWARD
SUNSHINE SHOULD BECOME WIDESPREAD THROUGH THE AFTERNOON HOURS OF
FRIDAY. IT WILL BE A COOLER DAY FRIDAY...WHEN COMPARED TO RECENT
DAYS...THOUGH THE HIGHS ON FRIDAY WILL ACTUALLY RUN NEAR
NORMAL...WITH HIGHS IN THE LOW TO MID 40S.
BY FRIDAY NIGHT WEAK UPPER LEVEL RIDGING WILL CROSS THE
REGION...WITH THE SURFACE HIGH PASSING JUST TO THE SOUTH OF THE
REGION. THIS SHOULD ALLOW FOR A COOL NIGHT WITH OVERNIGHT LOWS
DROPPING INTO THE LOWER 30S REGION-WIDE.
SATURDAY A RETURN SOUTHEASTERLY FLOW BEHIND THE DEPARTING AREA OF
HIGH PRESSURE WILL ALLOW FOR MILDER AIR TO BRIEFLY RETURN TO THE
REGION. WITHIN THIS WARMING ALOFT THERE WILL BE ENOUGH ISENTROPIC
LIFT TO GENERATE A FAIR AMOUNT OF CLOUDS THROUGH THE DAY. THOUGH
WARMING IN THE MID LEVELS...SURFACE TEMPERATURES WILL BE VERY
SIMILAR TO FRIDAY WITH HIGHS AGAIN IN THE 40S. A FEW LOCATIONS ON
THE LAKE PLAIN SOUTH OF LAKE ONTARIO MAY REACH NEAR 50F AS A
SOUTHEASTERLY DOWNSLOPE FLOW WARMS ACROSS THESE AREAS.
SATURDAY WILL ALSO BECOME BREEZY AS A STORM SYSTEM TAKES A CLASSIC
HIGH WIND TRACK...FROM THE EASTERN CORN BELT STATES SATURDAY MORNING
TO JUST NORTH AND WEST OF LAKE ERIE LATE SATURDAY NIGHT AND LIFTING
INTO SOUTHERN CANADA SUNDAY MORNING. THE GFS IS MOST AGGRESSIVE WITH
THE DEEPENING OF THIS STORM SYSTEM WITH THE GFS20 DETERMINISTIC
MODEL DROPPING THE MSLP FROM 1011 MB SATURDAY MORNING OVER
ILLINOIS TO 989 MB SUNDAY MORNING JUST NORTHEAST OF LAKE
NIPISSING ON THE ONTARIO/QUEBEC BORDER. THE ECMWF ONLY DEEPENS
THIS LOW TO 997 MB SUNDAY MORNING WHILE THE NAM DEEPENS THE LOW TO
1009 MB. ALSO THE GFS ENSEMBLE MEMBERS ARE ALMOST ALL NOT NEARLY
AS DEEP AS THE DETERMINISTIC MODEL...WHICH LEADS TO THE GFS AS AN
OUTLIER THUS FAR FOR THE POTENTIAL WIND EVENT.
THOUGH A CLASSIC TRACK FOR HIGH WINDS...WITH AN ISALLOBARIC COUPLET
PASSING OVER VICINITY OF LAKE ERIE THE LLJ BETWEEN 925 AND 850 HPA
ONLY INCREASES TO ABOUT 45 TO 55 KNOTS...WITH AGAIN THE GFS
STRONGEST WITH THE LOW LEVEL WIND FIELD. WOULD LIKE TO SEE THE LLJ A
BIT STRONGER...AND BETTER MODEL CONSISTENCY...AND NOT THE OUTLIER
MODEL (GFS) AS THE STRONGEST WIND FIELD FOR YET ANOTHER HIGH WIND
EVENT. FOR NOW WILL CONTINUE TO MENTION THE POTENTIAL FOR GUSTY
WINDS IN THE HWO.
THIS STORM SYSTEM WILL BRING A COLD FRONT ACROSS THE REGION SATURDAY
NIGHT. ACCOMPANYING THIS COLD FRONT WILL BE RAIN SHOWERS AND HIGHER
ELEVATION SNOW...WITH A BAND OF PRECIPITATION PASSING ACROSS THE
REGION BEFORE A DRY SLOT BRINGS A TEMPORARY END TO THE
PRECIPITATION. AS THE COLD AIR DEEPENS AND TEMPERATURES AT 850 HPA
FALL TO AROUND -8C...PRECIPITATION SHOULD LARGELY BECOME ALL SNOW BY
SUNDAY MORNING. THIS COMBINED WITH SURFACE TEMPERATURES FALLING INTO
THE LOW TO MID 30S WILL INCREASINGLY SUPPORT SNOW SHOWERS...WITH A
MINOR ACCUMULATION POSSIBLE BY SUNDAY MORNING...MAINLY ACROSS THE
HILLS.
AS THIS COLD AIR DEEPENS OVER THE EASTERN GREAT LAKES ATTENTION WILL
QUICKLY CHANGE FROM THE SYNOPTIC PRECIPITATION ASSOCIATED WITH THE
COLD FRONT AND UPPER LEVEL TROUGH TO LAKE EFFECT PRECIPITATION
POTENTIAL. LAKE TEMPERATURES AVERAGING AROUND 10C SUNDAY...WITH 850
HPA TEMPERATURES FALLING TO AROUND -10C THROUGH THE COURSE OF SUNDAY
AND SUNDAY NIGHT WILL INCREASE LAKE INDUCED EQUILIBRIUM LEVELS TO
ABOUT 12K TO 15K FEET. LAKE EFFECT PRECIPITATION WILL BECOME LIKELY
EAST OF LAKE ERIE BY LATE SATURDAY NIGHT. MORE ON THE LAKE EFFECT
SET-UP IN THE LONG TERM DISCO BELOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS SATURDAY`S LOW MOVES OFF INTO QUEBEC SUNDAY...ALL OF THE
INGREDIENTS APPEAR TO BE IN PLACE FOR A BRIEF BUT POTENTIALLY
SIGNIFICANT LAKE EFFECT EVENT OFF LAKE ERIE IMPACTING THE WESTERN
SOUTHERN TIER AND OFF OF LAKE ONTARIO IMPACTING THE TUG HILL
PLATEAU. ENSEMBLES ARE IN EXCELLENT AGREEMENT ON THE SYNOPTIC SETUP
ACROSS THE REGION WITH A SURFACE/MID-LEVEL LOW LIFTING OFF TO THE
NORTHEAST ACROSS QUEBEC AND A SHARP UPPER LEVEL TROUGH UPSTREAM
ACROSS THE CENTRAL GREAT LAKES. COLD AIR WRAPPING IN BEHIND THE
SURFACE/MID-LEVEL FEATURES WILL ADVECT ACROSS THE LAKES ON WESTERLY
FLOW AND AS 850MB TEMPS FALL TO -10C...EQUILIBRIUM LEVELS WILL CLIMB
ABOVE 15KFT BY DAYBREAK SUNDAY MORNING. WHILE DIURNAL EFFECTS SHOULD
HAMPER BAND DEVELOPMENT TO SOME EXTENT DURING THE DAY ON
SUNDAY...SYNOPTIC LIFT FROM THE UPPER LEVEL TROUGH MAY COMPENSATE
FOR THIS AS IT MOVES THROUGH BY SUNDAY EVENING WITH A BRIEF PERIOD
OF POTENTIAL UPSTREAM CONNECTION OFF OF LAKE HURON AS FLOW VEERS TO
THE WNW LATER IN THE DAY AND INTO SUNDAY EVENING. INCREASING SHEAR
SUNDAY NIGHT AND MONDAY IN THE WAKE OF THE UPPER LEVEL TROUGH
PASSAGE SHOULD BRING AN END TO THE BULK OF THE SNOW BY MONDAY
MORNING OFF OF LAKE ERIE AND AROUND LATER IN THE DAY MONDAY OFF LAKE
ONTARIO. THE THREAT FOR ACCUMULATING LAKE EFFECT SNOW THIS WEEKEND
HAS ALSO BEEN ADDED TO THE HAZARDOUS WEATHER OUTLOOK. THERE WILL BE
SOME UNCERTAINTY AS TO HOW MUCH SNOW...ESPECIALLY EARLY IN THE EVENT
AS TEMPERATURES IN THE MID TO UPPER 30S SUNDAY MAY ALLOW FOR MORE
PLAIN RAIN TO FALL RATHER THAN SNOW. GREATEST SNOWFALL ACCUMULATION
EAST OF BOTH LAKES WILL LIKELY COME SUNDAY NIGHT AND INTO MONDAY
WHEN THE COLD AIR DEEPENS FURTHER.
LINGERING LAKE EFFECT SHOWERS ON LAKE ONTARIO WILL SHIFT NORTH INTO
THE SAINT LAWRENCE VALLEY MONDAY MORNING AND DISSIPATE ALTOGETHER BY
MONDAY AFTERNOON AS BROAD RIDGING AND ANTICYCLONIC FLOW TAKES OVER
ACROSS THE REGION IN THE WAKE OF THE TROUGH. TEMPERATURES WILL START
TO MODERATE ONCE AGAIN MONDAY NIGHT INTO TUESDAY AS THE SURFACE
RIDGE SHIFTS EAST...OPENING UP THE LOWER GREAT LAKES ONCE AGAIN TO
INCREASINGLY MILD SOUTHERLY FLOW AND DRY CONDITIONS. THIS RIDGING
WILL BECOME FURTHER ENTRENCHED ACROSS THE EAST AS A DEEP FULL-
LATITUDE TROUGH DIGS ACROSS THE WESTERN U.S. AND AT THIS POINT IT
APPEARS THAT THE UNSEASONABLY WARM AND DRY WEATHER MAY LAST AT LEAST
THROUGH THE THANKSGIVING HOLIDAY THANKS TO THIS RIDGING WHILE VERY
WET AND UNSETTLED WEATHER WILL PREVAIL JUST TO OUR WEST FROM THE
SOUTHERN PLAINS TO THE WESTERN GREAT LAKES AT THE INTERFACE BETWEEN
THE EASTERN RIDGE AND WESTERN TROUGH.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
DOWNSLOPING HAS KEPT CIGS VFR IN MOST AREAS...WITH MVFR CONDITIONS
AT JHW WHERE DOWNSLOPING HAS LESS OF AN IMPACT.
A COLD FRONT WILL PASS FROM W-E FROM 16Z THROUGH 22Z...WITH DRIER
AIR BEHIND IT LIKELY TO HELP LIFT AND SCATTER CLOUDS AND BRING A
PERIOD OF VFR CONDITIONS. THERE MAY BE SOME LAKE EFFECT CLOUDS OR
SHOWERS TONIGHT E-NE OF THE LAKES...BUT FOR THE MOST PART THIS WILL
NOT IMPACT TAF SITES.
OUTLOOK...
FRIDAY...MAINLY VFR.
SATURDAY...AREAS OF MVFR WITH A CHANCE OF SHOWERS.
SATURDAY NIGHT AND SUNDAY...AREAS OF MVFR/IFR WITH SNOW SHOWERS
LIKELY...ESPECIALLY EAST OF THE LAKES.
MONDAY...VFR...EXCEPT MVFR/IFR POSSIBLE EAST OF THE LAKES WITH
LINGERING LAKE EFFECT SNOW SHOWERS.
&&
.MARINE...
WINDS WILL STILL BE STRONG AHEAD OF THE COLD FRONT...AND THEN AGAIN
BEHIND IT. MARINE HEADLINES HAVE BEEN ADJUSTED WITH A FAIRLY
EXTENDED PERIOD OF SMALL CRAFT ADVISORIES IN MOST AREAS. ONE
POTENTIAL CONCERN IS THAT WINDS MAY BRIEFLY APPROACH GALE BEHIND THE
COLD FRONT THIS EVENING. AT THIS TIME...THIS IS EXPECTED TO BE TOO
BRIEF TO ISSUE ANOTHER GALE WARNING...BUT THIS CAN BE MONITORED ON
FUTURE SHIFTS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 2 AM EST FRIDAY FOR LEZ020.
SMALL CRAFT ADVISORY UNTIL 1 AM EST SATURDAY FOR
LOZ043>045.
SMALL CRAFT ADVISORY UNTIL 10 PM EST FRIDAY FOR LOZ042.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
SLZ022-024.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL/CHURCH
SHORT TERM...THOMAS
LONG TERM...THOMAS/WOOD
AVIATION...APFFEL/CHURCH
MARINE...APFFEL/CHURCH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
709 AM EST THU NOV 19 2015
.SYNOPSIS...
A STORM SYSTEM WILL LIFT INTO HUDSON BAY AND PUSH A COLD FRONT
ACROSS OUR REGION TODAY. AHEAD OF THIS FRONT IT WILL BE WARM AND
WINDY WITH SOME SHOWERS...BUT MORE SEASONABLY COOL TEMPERATURES WILL
BUILD INTO THE REGION BEHIND THE FRONT TONIGHT AND FRIDAY. COLDER
WEATHER WILL RETURN THIS WEEKEND WITH SOME LAKE EFFECT SNOW SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE CORE OF A 60 KT LLJ HAS SHIFTED EAST OF ROCHESTER...RESULTING
IN DIMINISHING (BUT STILL BREEZY) WINDS ACROSS WESTERN NEW YORK.
GUSTS TO 50 MPH ARE STILL POSSIBLE IN JEFFERSON COUNTY WHERE
DOWNSLOPING WILL HELP MIX A PORTION OF THESE WINDS TO THE SURFACE.
ELSEWHERE THE WIND ADVISORY HAD BEEN ALLOWED TO EXPIRE.
OTHER THAN THE WINDS...IT WILL BE UNSEASONABLY WARM THIS MORNING
WITH TEMPERATURES IN THE 60S IN MOST AREAS. THE LLJ AND A MID-LEVEL
DISTURBANCE WILL GENERATE LIFT AND AN AREA OF SHOWERS. CONSENSUS
QPF SUGGESTS THE STEADIEST SHOWERS WILL BE ACROSS THE EASTERN LAKE
ONTARIO REGION TODAY. QPF HAS BEEN OVERDONE WITH DOWNSLOPE DRYING
THE LIKELY CAUSE. BASED ON THIS HAVE ACCEPTED THE MODEL MEAN
POSITION...BUT HAVE REDUCED AMOUNTS.
THE HRRR AND OTHER HIGH RESOLUTION GUIDANCE ALSO DEVELOPS SOME
SHOWERS ALONG THE FRONT WHICH MAY BRING ANOTHER QUICK ROUND OF
SHOWERS TO AREAS NORTH OF I-90. THE COLD FRONT WILL ENTER WESTERN
NEW YORK AROUND NOON...AND SWEEP FROM W-E DURING THE AFTERNOON
HOURS. THIS WILL BRING COOLER (BUT NOT YET COLD) AIR INTO THE
REGION THIS AFTERNOON AND ALSO BRING AN END TO THE SHOWERS.
COLD AIR ADVECTION WILL CONTINUE TONIGHT FROM A MODERATE WSW FLOW.
THIS AIR MASS IS QUITE DRY WHICH SHOULD SUPPRESS LAKE EFFECT
ACTIVITY...HOWEVER WITH CONSENSUS 850MB TEMPERATURE FORECAST TO DROP
TO AROUND -7C THERE WILL BE QUITE A BIT OF LAKE INDUCED INSTABILITY.
THE MAJORITY OF HIGH RESOLUTION GUIDANCE DOES NOT FORECAST ANY LAKE
EFFECT RAIN OR SNOW SHOWERS...WITH THE RGEM GUIDANCE A NOTABLE
EXCEPTION. GIVEN THE DELTA T VALUES AND THE FAIRLY GOOD TRACK RECORD
OF THE RGEM GUIDANCE CHANCE POPS WILL BE INTRODUCED EAST OF LAKE
ERIE. ANY SHOWERS WOULD START OFF AS RAIN...BUT CHANGE OVER TO SNOW
LATE TONIGHT AS TEMPERATURES COOL. SPEAKING OF TEMPERATURES...NEW
GUIDANCE SUPPORTS COLDER LOW TEMPERATURES FOR TONIGHT...WITH MOST
AREAS EXPECTED TO DROP INTO THE 30S BY DAYBREAK FRIDAY MORNING.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
FRIDAY SURFACE HIGH PRESSURE WILL BULGE NORTHEASTWARD FROM THE LOWER
OHIO VALLEY...AND SPREAD FAIR WEATHER TO THE EASTERN GREAT LAKES
REGION. THERE MAY BE A LITTLE LINGERING LAKE EFFECT
PRECIPITATION EAST OF LAKE ERIE. WHILE TEMPERATURES AT 850 HPA (-6 TO
-8C) WILL BE COOL ENOUGH TO SUPPORT A LAKE EFFECT RESPONSE THE DRIER
AIR ASSOCIATED WITH THE SURFACE HIGH PRESSURE MAY BE JUST ENOUGH TO
PREVENT A BAND OF PRECIPITATION FROM FORMING. FOR NOW WILL CARRY A
LOW CHANCE POP FOR EAST OF LAKE ONTARIO THROUGH THE MORNING HOURS OF
FRIDAY.
THERE WILL REMAIN AN UPPER LEVEL TROUGH OVER THE REGION FRIDAY
MORNING...AND THIS FEATURE WITH ITS COOLER POOL OF AIR ALOFT MAY
ALSO ALLOW FOR SOME CLOUDS TO LINGER ACROSS THE REGION IN ADDITION
TO THE LAKE EFFECT CLOUDS. CLOUDS UNDER THE TROUGH WILL BE MOST
LIKELY TOWARDS THE EAST FOR THE FINGER LAKES AND EASTERN LAKE
ONTARIO REGION. AS THE UPPER LEVEL TROUGH LIFTS NORTHEASTWARD
SUNSHINE SHOULD BECOME WIDESPREAD THROUGH THE AFTERNOON HOURS OF
FRIDAY. IT WILL BE A COOLER DAY FRIDAY...WHEN COMPARED TO RECENT
DAYS...THOUGH THE HIGHS ON FRIDAY WILL ACTUALLY RUN NEAR
NORMAL...WITH HIGHS IN THE LOW TO MID 40S.
BY FRIDAY NIGHT WEAK UPPER LEVEL RIDGING WILL CROSS THE
REGION...WITH THE SURFACE HIGH PASSING JUST TO THE SOUTH OF THE
REGION. THIS SHOULD ALLOW FOR A COOL NIGHT WITH OVERNIGHT LOWS
DROPPING INTO THE LOWER 30S REGION-WIDE.
SATURDAY A RETURN SOUTHEASTERLY FLOW BEHIND THE DEPARTING AREA OF
HIGH PRESSURE WILL ALLOW FOR MILDER AIR TO BRIEFLY RETURN TO THE
REGION. WITHIN THIS WARMING ALOFT THERE WILL BE ENOUGH ISENTROPIC
LIFT TO GENERATE A FAIR AMOUNT OF CLOUDS THROUGH THE DAY. THOUGH
WARMING IN THE MID LEVELS...SURFACE TEMPERATURES WILL BE VERY
SIMILAR TO FRIDAY WITH HIGHS AGAIN IN THE 40S. A FEW LOCATIONS ON
THE LAKE PLAIN SOUTH OF LAKE ONTARIO MAY REACH NEAR 50F AS A
SOUTHEASTERLY DOWNSLOPE FLOW WARMS ACROSS THESE AREAS.
SATURDAY WILL ALSO BECOME BREEZY AS A STORM SYSTEM TAKES A CLASSIC
HIGH WIND TRACK...FROM THE EASTERN CORN BELT STATES SATURDAY MORNING
TO JUST NORTH AND WEST OF LAKE ERIE LATE SATURDAY NIGHT AND LIFTING
INTO SOUTHERN CANADA SUNDAY MORNING. THE GFS IS MOST AGGRESSIVE WITH
THE DEEPENING OF THIS STORM SYSTEM WITH THE GFS20 DETERMINISTIC
MODEL DROPPING THE MSLP FROM 1011 MB SATURDAY MORNING OVER
ILLINOIS TO 989 MB SUNDAY MORNING JUST NORTHEAST OF LAKE
NIPISSING ON THE ONTARIO/QUEBEC BORDER. THE ECMWF ONLY DEEPENS
THIS LOW TO 997 MB SUNDAY MORNING WHILE THE NAM DEEPENS THE LOW TO
1009 MB. ALSO THE GFS ENSEMBLE MEMBERS ARE ALMOST ALL NOT NEARLY
AS DEEP AS THE DETERMINISTIC MODEL...WHICH LEADS TO THE GFS AS AN
OUTLIER THUS FAR FOR THE POTENTIAL WIND EVENT.
THOUGH A CLASSIC TRACK FOR HIGH WINDS...WITH AN ISALLOBARIC COUPLET
PASSING OVER VICINITY OF LAKE ERIE THE LLJ BETWEEN 925 AND 850 HPA
ONLY INCREASES TO ABOUT 45 TO 55 KNOTS...WITH AGAIN THE GFS
STRONGEST WITH THE LOW LEVEL WIND FIELD. WOULD LIKE TO SEE THE LLJ A
BIT STRONGER...AND BETTER MODEL CONSISTENCY...AND NOT THE OUTLIER
MODEL (GFS) AS THE STRONGEST WIND FIELD FOR YET ANOTHER HIGH WIND
EVENT. FOR NOW WILL CONTINUE TO MENTION THE POTENTIAL FOR GUSTY
WINDS IN THE HWO.
THIS STORM SYSTEM WILL BRING A COLD FRONT ACROSS THE REGION SATURDAY
NIGHT. ACCOMPANYING THIS COLD FRONT WILL BE RAIN SHOWERS AND HIGHER
ELEVATION SNOW...WITH A BAND OF PRECIPITATION PASSING ACROSS THE
REGION BEFORE A DRY SLOT BRINGS A TEMPORARY END TO THE
PRECIPITATION. AS THE COLD AIR DEEPENS AND TEMPERATURES AT 850 HPA
FALL TO AROUND -8C...PRECIPITATION SHOULD LARGELY BECOME ALL SNOW BY
SUNDAY MORNING. THIS COMBINED WITH SURFACE TEMPERATURES FALLING INTO
THE LOW TO MID 30S WILL INCREASINGLY SUPPORT SNOW SHOWERS...WITH A
MINOR ACCUMULATION POSSIBLE BY SUNDAY MORNING...MAINLY ACROSS THE
HILLS.
AS THIS COLD AIR DEEPENS OVER THE EASTERN GREAT LAKES ATTENTION WILL
QUICKLY CHANGE FROM THE SYNOPTIC PRECIPITATION ASSOCIATED WITH THE
COLD FRONT AND UPPER LEVEL TROUGH TO LAKE EFFECT PRECIPITATION
POTENTIAL. LAKE TEMPERATURES AVERAGING AROUND 10C SUNDAY...WITH 850
HPA TEMPERATURES FALLING TO AROUND -10C THROUGH THE COURSE OF SUNDAY
AND SUNDAY NIGHT WILL INCREASE LAKE INDUCED EQUILIBRIUM LEVELS TO
ABOUT 12K TO 15K FEET. LAKE EFFECT PRECIPITATION WILL BECOME LIKELY
EAST OF LAKE ERIE BY LATE SATURDAY NIGHT. MORE ON THE LAKE EFFECT
SET-UP IN THE LONG TERM DISCO BELOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS SATURDAY`S LOW MOVES OFF INTO QUEBEC SUNDAY...ALL OF THE
INGREDIENTS APPEAR TO BE IN PLACE FOR A BRIEF BUT POTENTIALLY
SIGNIFICANT LAKE EFFECT EVENT OFF LAKE ERIE IMPACTING THE WESTERN
SOUTHERN TIER AND OFF OF LAKE ONTARIO IMPACTING THE TUG HILL
PLATEAU. ENSEMBLES ARE IN EXCELLENT AGREEMENT ON THE SYNOPTIC SETUP
ACROSS THE REGION WITH A SURFACE/MID-LEVEL LOW LIFTING OFF TO THE
NORTHEAST ACROSS QUEBEC AND A SHARP UPPER LEVEL TROUGH UPSTREAM
ACROSS THE CENTRAL GREAT LAKES. COLD AIR WRAPPING IN BEHIND THE
SURFACE/MID-LEVEL FEATURES WILL ADVECT ACROSS THE LAKES ON WESTERLY
FLOW AND AS 850MB TEMPS FALL TO -10C...EQUILIBRIUM LEVELS WILL CLIMB
ABOVE 15KFT BY DAYBREAK SUNDAY MORNING. WHILE DIURNAL EFFECTS SHOULD
HAMPER BAND DEVELOPMENT TO SOME EXTENT DURING THE DAY ON
SUNDAY...SYNOPTIC LIFT FROM THE UPPER LEVEL TROUGH MAY COMPENSATE
FOR THIS AS IT MOVES THROUGH BY SUNDAY EVENING WITH A BRIEF PERIOD
OF POTENTIAL UPSTREAM CONNECTION OFF OF LAKE HURON AS FLOW VEERS TO
THE WNW LATER IN THE DAY AND INTO SUNDAY EVENING. INCREASING SHEAR
SUNDAY NIGHT AND MONDAY IN THE WAKE OF THE UPPER LEVEL TROUGH
PASSAGE SHOULD BRING AN END TO THE BULK OF THE SNOW BY MONDAY
MORNING OFF OF LAKE ERIE AND AROUND LATER IN THE DAY MONDAY OFF LAKE
ONTARIO. THE THREAT FOR ACCUMULATING LAKE EFFECT SNOW THIS WEEKEND
HAS ALSO BEEN ADDED TO THE HAZARDOUS WEATHER OUTLOOK. THERE WILL BE
SOME UNCERTAINTY AS TO HOW MUCH SNOW...ESPECIALLY EARLY IN THE EVENT
AS TEMPERATURES IN THE MID TO UPPER 30S SUNDAY MAY ALLOW FOR MORE
PLAIN RAIN TO FALL RATHER THAN SNOW. GREATEST SNOWFALL ACCUMULATION
EAST OF BOTH LAKES WILL LIKELY COME SUNDAY NIGHT AND INTO MONDAY
WHEN THE COLD AIR DEEPENS FURTHER.
LINGERING LAKE EFFECT SHOWERS ON LAKE ONTARIO WILL SHIFT NORTH INTO
THE SAINT LAWRENCE VALLEY MONDAY MORNING AND DISSIPATE ALTOGETHER BY
MONDAY AFTERNOON AS BROAD RIDGING AND ANTICYCLONIC FLOW TAKES OVER
ACROSS THE REGION IN THE WAKE OF THE TROUGH. TEMPERATURES WILL START
TO MODERATE ONCE AGAIN MONDAY NIGHT INTO TUESDAY AS THE SURFACE
RIDGE SHIFTS EAST...OPENING UP THE LOWER GREAT LAKES ONCE AGAIN TO
INCREASINGLY MILD SOUTHERLY FLOW AND DRY CONDITIONS. THIS RIDGING
WILL BECOME FURTHER ENTRENCHED ACROSS THE EAST AS A DEEP FULL-
LATITUDE TROUGH DIGS ACROSS THE WESTERN U.S. AND AT THIS POINT IT
APPEARS THAT THE UNSEASONABLY WARM AND DRY WEATHER MAY LAST AT LEAST
THROUGH THE THANKSGIVING HOLIDAY THANKS TO THIS RIDGING WHILE VERY
WET AND UNSETTLED WEATHER WILL PREVAIL JUST TO OUR WEST FROM THE
SOUTHERN PLAINS TO THE WESTERN GREAT LAKES AT THE INTERFACE BETWEEN
THE EASTERN RIDGE AND WESTERN TROUGH.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
A 50-60 LLJ FROM ROC-ART WILL MOVE EAST OF THE AREA AROUND 16Z.
THIS HAS STRUGGLED TO MIX TO THE SURFACE...BUT THERE STILL MAY BE
SOME HIGHER GUSTS AT ART. THIS HAS RESULTED IN SOME WIND
SHEAR...BUT THUS FAR MIXING HAS BEEN AMPLE KEEP THIS SHY OF LLWS
CRITERIA IN THE TAFS. OTHERWISE...DOWNSLOPING HAS KEPT CIGS VFR
IN MOST AREAS...WITH MVFR CONDITIONS AT JHW WHERE DOWNSLOPING HAS
LESS OF AN IMPACT.
A COLD FRONT WILL PASS FROM W-E FROM 16Z THROUGH 22Z...WITH DRIER
AIR BEHIND IT LIKELY TO HELP LIFT AND SCATTER CLOUDS AND BRING A
PERIOD OF VFR CONDITIONS. THERE MAY BE SOME LAKE EFFECT CLOUDS OR
SHOWERS TONIGHT E-NE OF THE LAKES...BUT FOR THE MOST PART THIS WILL
NOT IMPACT TAF SITES.
OUTLOOK...
FRIDAY...MAINLY VFR.
SATURDAY...AREAS OF MVFR WITH A CHANCE OF SHOWERS.
SATURDAY NIGHT AND SUNDAY...AREAS OF MVFR/IFR WITH SNOW SHOWERS
LIKELY...ESPECIALLY EAST OF THE LAKES.
MONDAY...VFR...EXCEPT MVFR/IFR POSSIBLE EAST OF THE LAKES WITH
LINGERING LAKE EFFECT SNOW SHOWERS.
&&
.MARINE...
STRONG SOUTHERLY WINDS HAVE DROPPED ENOUGH TO ALLOW THE GALES TO
EXPIRE ON LAKE ERIE. WINDS WILL STILL BE STRONG AHEAD OF THE COLD
FRONT...AND THEN AGAIN BEHIND IT. MARINE HEADLINES HAVE BEEN
ADJUSTED WITH A FAIRLY EXTENDED PERIOD OF SMALL CRAFT ADVISORIES IN
MOST AREAS. ONE POTENTIAL CONCERN IS THAT WINDS MAY BRIEFLY APPROACH
GALE BEHIND THE COLD FRONT THIS EVENING. AT THIS TIME...THIS IS
EXPECTED TO BE TOO BRIEF TO ISSUE ANOTHER GALE WARNING...BUT THIS
CAN BE MONITORED ON FUTURE SHIFTS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WIND ADVISORY UNTIL 10 AM EST THIS MORNING FOR NYZ007.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 2 AM EST FRIDAY FOR LEZ020.
SMALL CRAFT ADVISORY UNTIL 1 AM EST SATURDAY FOR
LOZ043>045.
SMALL CRAFT ADVISORY UNTIL 10 PM EST FRIDAY FOR LOZ042.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
SLZ022-024.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...THOMAS
LONG TERM...THOMAS/WOOD
AVIATION...APFFEL
MARINE...APFFEL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
955 AM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL CROSS CENTRAL NORTH CAROLINA THIS
AFTERNOON AND EVENING. HIGH PRESSURE WILL BUILD OVER THE REGION ON
FRIDAY. A MAINLY DRY COLD FRONT WILL SWEEP ACROSS THE REGION
SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 AM THURSDAY...
WIDESPREAD MODERATE SHOWERS WITH EMBEDDED STORMS PERSIST OVER THE
ERN CWA. PONDING OF WATER ON STREETS AND OTHER FLOODING OF URBAN AND
LOW LYING AREAS HAS BEEN COMMON WITH RAINFALL RATES UP TO 1-2" PER
HOUR. INSTABILITY THUS FAR HAS BEEN MEAGER... ALTHOUGH MUCAPE VALUES
OF 100-250 J/KG (WHICH APPEARS TO BE MOSTLY RESTRICTED TO THE MID
AND HIGH LEVELS) COMBINED WITH STRONG FOCUSED UPPER DIVERGENCE HAS
BEEN SUFFICIENT FOR NUMEROUS LIGHTNING FLASHES (MOSTLY POSITIVE
STRIKES) WITHIN THE HEAVIER SHOWERS. LOW LEVEL SHEAR OF 30-40 KTS
HERE WITH 0-1 SRH VALUES OVER 300 M2/S2 WARRANTS CLOSE MONITORING
FOR ANY ENHANCED WIND SIGNATURES OR WEAK ROTATION OVER OUR SE OVER
THE NEXT FEW HOURS. OTHERWISE... WINDS ALOFT WILL SLOWLY VEER TO
MORE SW AS THE 850-700 MB TROUGH AXES ROTATE NE THROUGH ERN NC...
AND AS THE VERY HIGH PW AND LOW LEVEL MOISTURE TRANSPORT TRANSLATE
SLOWLY NORTHEASTWARD INTO THE AFTERNOON... RAINFALL WILL SLOWLY
TAPER DOWN FROM WEST TO EAST. WATER VAPOR IMAGERY SHOWS A VERY
PRONOUNCED BACK EDGE TO THE DEEPER MOISTURE BUT WITH A STEERING FLOW
HOLDING ROUGHLY PARALLEL TO THE SURFACE FRONTAL ZONE (WHICH IS
ANALYZED OVER FAR WRN NC) AND ANOTHER MID LEVEL VORTICITY LOBE STILL
TO COME THROUGH THIS AFTERNOON... IT WILL TAKE UNTIL LATER TODAY FOR
THE SURFACE FRONTAL ZONE TO BE PROPELLED NORTHEASTWARD THROUGH
CENTRAL NC. LOW LEVEL MOISTURE SHOULD HOLD OVER MUCH OF CENTRAL NC
BEHIND THE MAIN RAIN SHIELD WITH A DELAY IN DOWNSLOPE LOW LEVEL
FLOW... WHICH WILL KEEP A CHANCE OF SHALLOW SHOWERS AREAWIDE THROUGH
MUCH OF THE AFTERNOON... ALONG WITH A BRIEF FOG THREAT WHERE SURFACE
WINDS EAST OF THE MOUNTAINS BECOME LIGHT AND VARIABLE FOR A TIME
AHEAD OF THE FRONT. EXPECT HIGHS FROM AROUND 70 TO THE MID 70S... IN
LINE WITH HI-RES RAPID UPDATE GUIDANCE. -GIH
PREVIOUS DISCUSSION AS OF 410 AM THURSDAY: A LARGE AREA OF RAIN...
WITH A FEW EMBEDDED CONVECTIVE ELEMENTS...IS CURRENTLY TRANSLATING
EAST ACROSS THE FORECAST AREA AS A 50KT PREFRONTAL LOW-LEVEL JET
LIFTS NORTH TOWARD THE MID-ATLANTIC STATES 9PER REGIONAL VWP). THE
CONVECTIVE ELEMENTS LACK ANY LIGHTNING OR STRONG WIND SIGNATURES...
AND GIVEN THE LACK OF ANALYZED INSTABILITY NORTH OF THE SAVANNAH
RIVER BASIN...WE MAY BE FREE OF THUNDERSTORMS FOR THE EARLY MORNING
HOURS. LATER THIS MORNING...VEERING SURFACE WINDS AHEAD OF THE MAIN
COLD FRONT...WHICH IS CURRENTLY MOVING THROUGH NORTHERN GEORGIA AND
EASTERN TN/KY...SHOULD TAP INTO NEAR 70 DEWPOINT AIR OVER EAST-
CENTRAL SC AND LEAD TO SOME WEAK DESTABILIZATION (250-500 J/KG
MLCAPE) FROM THE SANDHILLS INTO THE COASTAL PLAIN BY MIDDAY. THERE
IS NO REAL CONSENSUS IN NEAR TERM GUIDANCE REGARDING THE COVERAGE OF
ADDITIONAL SHOWERS AND STORMS...SOME SHOW A BROKEN LINE AND SOME
SHOW JUST SCATTERED CONVECTION. THE BACK EDGE TO THE DEEP MOISTURE
IS RAPIDLY PUSHING EAST ACROSS THE MOUNTAINS AND IS OUTPACING THE
COLD FRONT....SO DEEP MOISTURE WILL BE LACKING BY THE TIME THE FRONT
ARRIVES. HOWEVER...THE RAP SHOWS A PRE-FRONTAL TROUGH THAT MAY
PROVIDE A FOCUS FOR SOME SCATTERED CONVECTION...MAINLY US 1 AND EAST
BY MIDDAY...AND A FEW ADDITIONAL SHOWERS EVEN POSSIBLE WITH THE
PRIMARY COLD FRONT LATER THIS AFTERNOON AND EVENING. IF SOME
MODERATELY DEEP CONVECTION CAN INITIATE TODAY...0-6KM BULK SHEAR
VALUES OF 35-45KT WOULD CERTAINLY SUPPORT A DAMAGING WIND THREAT.
HIGHS WILL CLIMB BACK INTO THE MID 70S IN MOST AREAS...PARTICULARLY
IN THE WEST BEHIND THE CLEARING BUT AHEAD OF THE FRONT.
THE COLD FRONT WILL SWEEP ACROSS THE AREA BY EARLY EVENING...LEADING
TO COLD ADVECTION FOR MOST OF THE OVERNIGHT PERIOD AND LOWS DROPPING
INTO THE 40S FOR MOST OF CENTRAL NC.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 345 AM THURSDAY...
BENEATH BRIEF HEIGHT RISES IN BROAD WSW FLOW ALOFT... CONTINENTAL
POLAR HIGH PRESSURE AND AN ASSOCIATED DEEPLY DRY AIR MASS WILL BUILD
EAST ACROSS THE TN VALLEY AND APPALACHIANS THROUGH FRI NIGHT. THE
RIDGE WILL BE SHORT-LIVED HOWEVER...AS A SHARP SHORTWAVE TROUGH AND
"ALBERTA CLIPPER" LOW AMPLIFY INTO THE CENTRAL PLAINS/MID MS VALLEY
REGION...THEN LIFT/TURN NORTHEASTWARD THROUGH THE GREAT LAKES SAT-
SAT NIGHT. AN ASSOCIATED TRAILING POLAR FRONT WILL MOVE EAST ACROSS
CENTRAL NC SAT NIGHT-EARLY SUNDAY. AT THE SAME TIME...THE MODELS TO
VARYING DEGREES INDICATE AN ACTIVE SOUTHERN STREAM JET WILL SUPPORT
A WAVE OR WAVES OF LOW PRESSURE ALONG A DEVELOPING/SHARPENING
COASTAL FRONT ALONG THE SOUTHEAST US COAST...RAISING THE STAKES FOR
SOME INTERACTION OF THE TWO AS THE POLAR FRONT COLLAPSES EAST AND
INTERCEPTS DEEPENING MOISTURE CENTERED ALONG THE COASTAL CAROLINAS.
WHILE THE GFS REMAINS DRY...WITH MORE LIMITED DEEP MOISTURE OVER
CENTRAL NC...THE CONSENSUS OF OTHER GUIDANCE INCLUDING THE LATEST
EC/NMM/SREF/GEM...ALL SUPPORT VERY LIGHT QPF OVER THE EASTERN
PIEDMONT/SANDHILLS/COASTAL PLAIN SAT NIGHT...AT WHICH TIME A SLIGHT
CHANCE OF SHOWERS HAVE ACCORDINGLY BEEN INTRODUCED GENERALLY EAST OF
US HIGHWAY 1.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM THURSDAY...
THE 00Z/19TH ECMWF IS AN AGGRESSIVE OUTLIER THAT HOLDS THE
ASSOCIATED MERGED FRONTAL ZONE JUST OFFSHORE THROUGH SUN
NIGHT...WITH AN AXIS OF A QUARTER TO HALF INCH OF QPF LINGERING AS
FAR WEST AS THE I-95 CORRIDOR DURING THAT TIME. WILL FOLLOW WPC/S
PREFERENCE TOWARD A MORE PROGRESSIVE FRONTAL DEPARTURE AND
INCREASINGLY INFLUENTIAL...AND RENEWED...CONTINENTAL POLAR RIDGING
FROM THE WEST FOR THE PERIOD SUNDAY THROUGH MID-WEEK. THE ASSOCIATED
COOLEST TEMPERATURES WILL OCCUR SUN-MON...WITH HIGHS MOSTLY IN THE
UPPER 40S TO LOW 50S...AND LOWS IN THE MID-UPPER 20S...AND WITH
MODERATION INTO THE 50S AND 30S...RESPECTIVELY...THROUGH THE END OF
THE PERIOD.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 650 AM THURSDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD THIS MORNING..WITH AN AREA OF HEAVY RAIN AND A FEW ISOLATED
STORMS BETWEEN ROUGHLY KVUJ AND KFAY MOVING NORTHEAST. MANY
TERMINALS...INCLUDING KRDU AND KRWI...CAN EXPECT LIMITED
VSBYS/CEILINGS AND BRIEF WIND GUSTS OF 20-30KT IN THIS HEAVY RAIN.
ALL OF THIS ACTIVITY SHOULD MOVE EAST OF KRWI BY 16Z...WITH A LOW
END CHANCE OF ADDITIONAL SHOWERS OR STORMS THIS AFTERNOON.
CONFIDENCE IN THIS REDEVELOPMENT IS TOO LOW FOR THE TAF RIGHT NOW. A
COLD FRONT TO THE WEST WILL MOVE ACROSS THE AREA THIS AFTERNOON AND
EVENING...WITH A SOUTH TO NORTHWEST WIND SHIFT BETWEEN 18Z AND 00Z.
IF THE FRONT IS SLOWER THAN EXPECTED...SOME BRIEF FOG MAY BE
POSSIBLE AT KFAY AND KRWI. .
OUTLOOK: EXPECT A RETURN TO VFR CONDITIONS WITH A VERY SLIGHT CHANCE
OF PRECIPITATION WITH A FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING
BUT OTHERWISE DRY CONDITIONS SHOULD PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...HARTFIELD/22
SHORT TERM...26
LONG TERM...26
AVIATION...77/22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
650 AM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL CROSS CENTRAL NORTH CAROLINA THIS
AFTERNOON AND EVENING...FOLLOWED BY HIGH PRESSURE BUILDING OVER THE
REGION ON FRIDAY. A MOISTURE STARVED COLD FRONT WILL SWEEP
ACROSS THE REGION SATURDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 410 AM THURSDAY...
A LARGE AREA OF RAIN... WITH A FEW EMBEDDED CONVECTIVE ELEMENTS...IS
CURRENTLY TRANSLATING EAST ACROSS THE FORECAST AREA AS A 50KT
PREFRONTAL LOW-LEVEL JET LIFTS NORTH TOWARD THE MID-ATLANTIC STATES
9PER REGIONAL VWP). THE CONVECTIVE ELEMENTS LACK ANY LIGHTNING OR
STRONG WIND SIGNATURES...AND GIVEN THE LACK OF ANALYZED INSTABILITY
NORTH OF THE SAVANNAH RIVER BASIN...WE MAY BE FREE OF THUNDERSTORMS
FOR THE EARLY MORNING HOURS. LATER THIS MORNING...VEERING SURFACE
WINDS AHEAD OF THE MAIN COLD FRONT...WHICH IS CURRENTLY MOVING
THROUGH NORTHERN GEORGIA AND EASTERN TN/KY...SHOULD TAP INTO NEAR 70
DEWPOINT AIR OVER EAST-CENTRAL SC AND LEAD TO SOME WEAK
DESTABILIZATION (250-500 J/KG MLCAPE) FROM THE SANDHILLS INTO THE
COASTAL PLAIN BY MIDDAY. THERE IS NO REAL CONSENSUS IN NEAR TERM
GUIDANCE REGARDING THE COVERAGE OF ADDITIONAL SHOWERS AND
STORMS...SOME SHOW A BROKEN LINE AND SOME SHOW JUST SCATTERED
CONVECTION. THE BACK EDGE TO THE DEEP MOISTURE IS RAPIDLY
PUSHING EAST ACROSS THE MOUNTAINS AND IS OUTPACING THE COLD
FRONT....SO DEEP MOISTURE WILL BE LACKING BY THE TIME THE FRONT
ARRIVES. HOWEVER...THE RAP SHOWS A PRE-FRONTAL TROUGH THAT MAY
PROVIDE A FOCUS FOR SOME SCATTERED CONVECTION...MAINLY US 1 AND EAST
BY MIDDAY...AND A FEW ADDITIONAL SHOWERS EVEN POSSIBLE WITH THE
PRIMARY COLD FRONT LATER THIS AFTERNOON AND EVENING. IF SOME
MODERATELY DEEP CONVECTION CAN INITIATE TODAY...0-6KM BULK SHEAR
VALUES OF 35-45KT WOULD CERTAINLY SUPPORT A DAMAGING WIND THREAT.
HIGHS WILL CLIMB BACK INTO THE MID 70S IN MOST AREAS...PARTICULARLY
IN THE WEST BEHIND THE CLEARING BUT AHEAD OF THE FRONT.
THE COLD FRONT WILL SWEEP ACROSS THE AREA BY EARLY EVENING...LEADING
TO COLD ADVECTION FOR MOST OF THE OVERNIGHT PERIOD AND LOWS DROPPING
INTO THE 40S FOR MOST OF CENTRAL NC.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 345 AM THURSDAY...
BENEATH BRIEF HEIGHT RISES IN BROAD WSW FLOW ALOFT... CONTINENTAL
POLAR HIGH PRESSURE AND AN ASSOCIATED DEEPLY DRY AIR MASS WILL BUILD
EAST ACROSS THE TN VALLEY AND APPALACHIANS THROUGH FRI NIGHT. THE
RIDGE WILL BE SHORT-LIVED HOWEVER...AS A SHARP SHORTWAVE TROUGH AND
"ALBERTA CLIPPER" LOW AMPLIFY INTO THE CENTRAL PLAINS/MID MS VALLEY
REGION...THEN LIFT/TURN NORTHEASTWARD THROUGH THE GREAT LAKES SAT-
SAT NIGHT. AN ASSOCIATED TRAILING POLAR FRONT WILL MOVE EAST ACROSS
CENTRAL NC SAT NIGHT-EARLY SUNDAY. AT THE SAME TIME...THE MODELS TO
VARYING DEGREES INDICATE AN ACTIVE SOUTHERN STREAM JET WILL SUPPORT
A WAVE OR WAVES OF LOW PRESSURE ALONG A DEVELOPING/SHARPENING
COASTAL FRONT ALONG THE SOUTHEAST US COAST...RAISING THE STAKES FOR
SOME INTERACTION OF THE TWO AS THE POLAR FRONT COLLAPSES EAST AND
INTERCEPTS DEEPENING MOISTURE CENTERED ALONG THE COASTAL CAROLINAS.
WHILE THE GFS REMAINS DRY...WITH MORE LIMITED DEEP MOISTURE OVER
CENTRAL NC...THE CONSENSUS OF OTHER GUIDANCE INCLUDING THE LATEST
EC/NMM/SREF/GEM...ALL SUPPORT VERY LIGHT QPF OVER THE EASTERN
PIEDMONT/SANDHILLS/COASTAL PLAIN SAT NIGHT...AT WHICH TIME A SLIGHT
CHANCE OF SHOWERS HAVE ACCORDINGLY BEEN INTRODUCED GENERALLY EAST OF
US HIGHWAY 1.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM THURSDAY...
THE 00Z/19TH ECMWF IS AN AGGRESSIVE OUTLIER THAT HOLDS THE
ASSOCIATED MERGED FRONTAL ZONE JUST OFFSHORE THROUGH SUN
NIGHT...WITH AN AXIS OF A QUARTER TO HALF INCH OF QPF LINGERING AS
FAR WEST AS THE I-95 CORRIDOR DURING THAT TIME. WILL FOLLOW WPC/S
PREFERENCE TOWARD A MORE PROGRESSIVE FRONTAL DEPARTURE AND
INCREASINGLY INFLUENTIAL...AND RENEWED...CONTINENTAL POLAR RIDGING
FROM THE WEST FOR THE PERIOD SUNDAY THROUGH MID-WEEK. THE ASSOCIATED
COOLEST TEMPERATURES WILL OCCUR SUN-MON...WITH HIGHS MOSTLY IN THE
UPPER 40S TO LOW 50S...AND LOWS IN THE MID-UPPER 20S...AND WITH
MODERATION INTO THE 50S AND 30S...RESPECTIVELY...THROUGH THE END OF
THE PERIOD.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 650 AM THURSDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD THIS MORNING..WITH AN AREA OF HEAVY RAIN AND A FEW ISOLATED
STORMS BETWEEN ROUGHLY KVUJ AND KFAY MOVING NORTHEAST. MANY
TERMINALS...INCLUDING KRDU AND KRWI...CAN EXPECT LIMITED
VSBYS/CEILINGS AND BRIEF WIND GUSTS OF 20-30KT IN THIS HEAVY RAIN.
ALLA OF THIS ACTIVITY SHOULD MOVE EAST OF KRWI BY 16Z...WITH A LOW
END CHANCE OF ADDITIONAL SHOWERS OR STORMS THIS AFTERNOON.
CONFIDENCE IN THIS REDEVELOPMENT IS TOO LOW FOR THE TAF RIGHT NOW. A
COLD FRONT TO THE WEST WILL MOVE ACROSS THE AREA THIS AFTERNOON AND
EVENING...WITH A SOUTH TO NORTHWEST WIND SHIFT BETWEEN 18Z AND 00Z.
IF THE FRONT IS SLOWER THAN EXPECTED...SOME BRIEF FOG MAY BE
POSSIBLE AT KFAY AND KRWI. .
OUTLOOK: EXPECT A RETURN TO VFR CONDITIONS WITH A VERY SLIGHT CHANCE
OF PRECIPITATION WITH A FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING
BUT OTHERWISE DRY CONDITIONS SHOULD PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...22
SHORT TERM...26
LONG TERM...26
AVIATION...77/22
AREA FORECAST DISCUSSION
NWS PORTLAND OR
405 AM PST THU NOV 19 2015
.SYNOPSIS...LOW PRESSURE IS MOVING ONSHORE NEAR LINCOLN CITY THIS
MORNING...BRINGING GUSTY SOUTH WINDS TO THE CENTRAL COAST AND PLENTY
OF RAIN AND HIGH ELEVATION SNOW TO NORTHWEST OREGON AND SOUTHWEST
WASHINGTON. EXPECT RAIN TO TAPER TO SHOWERS AS THE LOW MOVES EAST OF
THE CASCADES AND HIGH PRESSURE BUILDS IN FROM THE NORTHWEST. FLOW
WILL TURN OFFSHORE FRIDAY INTO THE UPCOMING WEEKEND AS COOL HIGH
PRESSURE SETTLES INTO THE INTERIOR PAC NW. THIS WILL LEAD TO A PERIOD
OF DRY BUT COOL WEATHER OVER THE WEEKEND. A COLD FRONT FROM THE GULF
OF ALASKA IS EXPECTED TO BRING THE NEXT CHANCE OF RAIN AND MOUNTAIN
SNOW MONDAY...WITH SHARPLY COLDER WEATHER SETTLING IN FOR MUCH OF
NEXT WEEK.
&&
.SHORT TERM...TODAY THROUGH SATURDAY...MSAS SURFACE ANALYSIS AND AREA
SURFACE OBSERVATIONS SHOW AN ELONGATED LOW PRESSURE CENTER MOVING
ONSHORE NEAR THE TILLAMOOK/LINCOLN COUNTY BORDER EARLY THIS MORNING.
TO THE SOUTH OF THIS...SOUTH WINDS HAVE INCREASED WITH GUSTS 40-45
MPH FAIRLY COMMON ALONG THE COAST. TO THE NORTH...WINDS HAVE REMAINED
MODERATE NORTHEASTERLY AND THUS WE DECIDED TO CANCEL THE HIGH WIND
WARNING FOR THE NORTH OREGON COAST AND COAST RANGE. DECIDED TO LET
THE HIGH WIND WARNING STAND FOR THE LANE/LINCOLN COUNTY COAST...BUT
IT MAY BE AN UPHILL BATTLE FOR IT TO VERIFY. SINCE THIS SYSTEM
APPEARS TO BE UNDERPERFORMING WIND-WISE...WE ALSO DECIDED TO CANCEL
THE WIND ADVISORY FOR THE CENTRAL AND SOUTHERN WILLAMETTE VALLEY. IT
APPEARS THE STRONGEST VALLEY GUSTS WILL BE PRIMARILY SOUTH OF ALBANY
AND INTO THE EUGENE AREA...BUT EVEN THERE IT WILL BE A STRUGGLE TO
GET GUSTS ABOVE 30 MPH PER MOST GUIDANCE AND LATEST TRENDS.
LOOKS LIKE IT WAS A GOOD CALL TO CANCEL THE FLOOD WATCH YESTERDAY AS
RAIN RATES HAVE NOT BEEN ALL THAT IMPRESSIVE. MOST OF THE FORECAST
AREA HAS SEEN STEADY LIGHT TO OCCASIONALLY MODERATE RAIN...WITH
RAINFALL TOTALS GENERALLY ON THE ORDER OF 0.50-1.00 INCH THUS FAR IN
NW OREGON AND LIGHTER AMOUNTS IN SW WASHINGTON. ANOTHER 0.50-1.00
INCH IS POSSIBLE MAINLY SOUTH OF SALEM...WHERE THE AXIS OF GREATEST
MOISTURE FLUX LIES. STORM TOTALS COULD REACH 1.50-3.00 INCHES IN THE
HIGHER TERRAIN SOUTH OF SALEM...PROBABLY NOT ENOUGH TO CAUSE MUCH IN
THE WAY OF HYDROLOGIC PROBLEMS.
SNOW LEVELS REMAIN IN THE 4500-5000 FT RANGE IN THE N OR/S WA
CASCADES...WITH WET SNOW SHOWING UP ON THE ODOT WEBCAM AT SANTIAM
PASS. SO FAR 3-6 INCHES OF SNOW HAVE FALLEN ABOVE 5000 FT FOR THE N
OR/S WA CASCADES...AND A FEW MORE INCHES ARE POSSIBLE BEFORE
PRECIPITATION TAPERS TO SHOWERS LATER THIS MORNING...ESPECIALLY MT
HOOD SOUTHWARD. WAS TEMPTED TO CANCEL THE SNOW ADVISORY FOR THE S WA
CASCADES AS RADAR TRENDS SEEM TO INDICATE PRECIP DWINDLING OVER THE
PAST COUPLE HOURS DUE TO THE SLIGHTLY MORE SOUTHERN TRACK OF THE LOW
VERSUS WHAT WAS EXPECTED. WILL KEEP AN EYE ON THIS THE NEXT COUPLE
HOURS...MAY SEND A QUICK UPDATE IF TO CANCEL THE ADVISORY FOR THE S
WA CASCADES IF THIS TREND CONTINUES.
LATEST FEW HRRR RUNS CONTINUE TO SHOW A FAIRLY SHARP BACK EDGE OF THE
PRECIP MOVING FROM NW TO SE LATER THIS MORNING THROUGH THIS EVENING.
THERE MAY EVEN BE A FEW SUNBREAKS FROM THE PORTLAND METRO
NORTHWESTWARD BY LATE AFTERNOON AS HIGH PRESSURE BEGINS TO BUILD IN
FROM THE NW. BY FRI MORNING OUR CWA SHOULD BE UNDER THE INFLUENCE OF
DRY NORTHERLY FLOW...WITH A CHILLY START TO THE DAY AND POSSIBLY
PATCHY VALLEY FOG.
COLD POOL HIGH PRESSURE IS EXPECTED TO STRENGTHEN EAST OF THE
CASCADES FRIDAY AND INTO THIS WEEKEND...YIELDING BRISK EAST WINDS
THROUGH THE GORGE. FUTURE SHIFTS MAY NEED TO LOOK AT INCREASING THE
EAST WINDS INTO THE PDX METRO AREA THIS WEEKEND AS LATEST NAM RUNS
HAVE BEEN SHOWING KTTD-KDLS GRADIENTS OF -5 TO -7 MB...WHICH COULD
PRODUCE GUSTS 50-70 MPH AT THE WINDIER LOCATIONS OF THE WEST GORGE
AND 30-40 MPH NEAR TROUTDALE. THIS SEEMS FAIRLY REASONABLE GIVEN THE
COLD POOL SETUP EXPECTED TO TAKE PLACE EAST OF THE CASCADES THE NEXT
FEW DAYS. THE OFFSHORE FLOW WILL BRING A BREAK IN PRECIPITATION...
WITH A DECENT AMOUNT OF SUNSHINE OUTSIDE OF PATCHY VALLEY FOG AWAY
FROM THE GORGE. WEAGLE
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...MODELS CONTINUE TO
ADVERTISE A PRETTY MAJOR PATTERN CHANGE IN THE LATTER PART OF THE
EXTENDED PERIOD. SAT NIGHT AND SUN LOOK TO REMAIN DRY WITH SOME
DEGREE OF OFFSHORE LOW-LEVEL FLOW. THERMALLY-INDUCED SURFACE TROUGH
RESIDES ALONG THE COAST SAT NIGHT THEN WEAKENS SUN. SHOULD SEE A
FAIRLY LARGE MIN TEMP RANGE SAT NIGHT WITH SUBSIDENCE INVERSIONS IN
THE HIGHER TERRAIN. THINGS START TO GET INTERESTING MON AS AN UPPER
TROUGH DIVES SOUTH FROM THE GULF OF ALASKA. THE OPERATIONAL ECMWF AND
GFS ARE SIMILAR IN THE OVERALL LARGE-SCALE PATTERN. COLD FRONTAL
BOUNDARY SLIDES SOUTH THROUGH WASHINGTON MON WITH 1000-500 MB
THICKNESS VALUES LOWERING TO NEAR 530 DM ACROSS SW WA AND FAR NW
OREGON 00Z TUE. BOTH MODELS THEN SHOW A RE-ENFORCING SHOT OF COLDER
AIR DIGGING INTO THE UPPER TROUGH MON NIGHT AND TUE. BY 00Z WED THE
OPERATIONAL ECMWF HAS THICKNESS VALUES IN THE LOW TO MID 520S AND 850
MB TEMPS AROUND -6C OVER SW WA AND FAR NW OREGON. SHOULD THIS
VERIFY...SNOW LEVELS WOULD BE DOWN TO AT LEAST 1000 FT...IF NOT A
LITTLE LOWER. THE COLD PATTERN HOLDS THROUGH WED. THE ECMWF IS MUCH
SLOWER PUSHING THE UPPER TROUGH SOUTH COMPARED TO THE GFS. IN
FACT...THE GFS SHOWS NELY FLOW ALOFT WED WITH COLD AIR STACKING UP
AGAINST THE S WA AND N OREGON CASCADES. GFS HAS 850 MB TEMPS OF -10C
TO -12C OVER THE S WA AND N OREGON CASCADE CREST 18Z WED. STILL TOO
EARLY TO TRY AND PIN DOWN THE FINER DETAILS...BUT CONFIDENCE IS
GROWING THAT WE MAY ENDURE A MUCH COLDER AIR MASS THE FIRST PART OF
NEXT WEEK. WEISHAAR.
&&
.AVIATION...WARM FRONTAL RAIN PUSHING ACROSS THE REGION THIS
MORNING AS ASSOCIATED SURFACE LOW MOVES ONSHORE AND EAST ACROSS
THE AREA LATER THIS MORNING. MIX OF IFR AND MVFR ACROSS THE
SOUTHERN PORTIONS OF THE AREA IN MODERATE STEADY RAIN. BREEZY
CONDITIONS ALSO CONTINUE...PARTICULARLY ALONG THE CENTRAL OREGON
COAST. LITTLE IMPROVEMENT THROUGH EARLY AFTERNOON WITH LOWER MVFR
TO IFR CIGS CONTINUING.
KPDX AND APPROACHES...MVFR CIGS/VSBYS CONTINUE THIS MORNING IN
RAIN. MAY SEE LOWERING CIGS FOR A MIX OF IFR TO LOW MVFR CIGS
THROUGH MUCH OF THE MORNING AND PERHAPS THROUGH THE EARLY
AFTERNOON. SOME IMPROVEMENT IN CIGS LIKELY BY MID AFTERNOON INTO
THE EVENING. EAST WINDS REMAIN REMAIN 10 TO 20 KT EARLY THIS
MORNING...DECREASING BY AROUND MIDDAY. CULLEN
&&
.MARINE...SURFACE LOW PRESSURE CONTINUES TO APPROACH THE
COAST...PRESENTLY ENTERING THE COASTAL WATERS /OR 60 NM
OFFSHORE/ WEST OF CASCADE HEAD. SOLID SMALL CRAFT WINDS CONTINUE
OVER ALL WATERS...WITH EAST WINDS OVER THE NORTHERN WATERS NORTH
OF THE LOW AND SOUTH TO SOUTHEAST WINDS TO THE SOUTH. AS
EXPECTED...THE STRONGEST GUSTS HAVE BEEN TO THE SOUTH AND
IMMEDIATELY AHEAD OF THE LOW. THEREFORE...WHILE GUSTS HAVE
REMAINED JUST SHY OF GALE CRITERIA TO THIS POINT...THE WINDOW OF
STRONGEST WINDS WILL CONTINUE THROUGH AROUND 6 AM. THUS...THE GALE
WARNING REMAINS IN EFFECT.
WINDS TURN MORE NORTHERLY ONCE THE LOW MOVES ONSHORE EARLY
THURSDAY...WITH ADVISORY LEVEL GUSTS CONTINUING INTO THURSDAY
EVENING. THEN...OVERALL WEAKLY DEFINED SURFACE PATTERN FOR MORE
BENIGN CONDITIONS. A THERMAL LOW BUILDS UP THE COAST FRIDAY AND
MAY REMAIN ALONG THE COAST THROUGH THE WEEKEND FOR OFFSHORE FLOW.
SEAS SOUTH OF CASCADE HEAD WILL REMAIN 12 TO 14 FT THIS MORNING
AS THE LOW MOVES ACROSS...BUT CONTINUE TO SUBSIDE NORTH INTO THE 7
TO 9 FT RANGE. SEAS SOUTH WILL SUBSIDE TO LESS THAN 10 FT BY
THURSDAY EVENING. CULLEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR NORTHERN
OREGON CASCADES.
HIGH WIND WARNING UNTIL 7 AM PST THIS MORNING FOR CENTRAL COAST
RANGE OF WESTERN OREGON-CENTRAL OREGON COAST.
WA...WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR SOUTH
WASHINGTON CASCADES.
PZ...GALE WARNING UNTIL 8 AM PST THIS MORNING FOR COASTAL WATERS FROM
CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 8 AM
THIS MORNING TO NOON PST TODAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
856 AM CST THU NOV 19 2015
.DISCUSSION...QUIET WEATHER CONDITIONS WILL PERSIST TODAY AS WINDS
GRADUALLY VEER TO THE E AND SLOWLY ADVECT LOW LEVEL MOISTURE BACK
INTO S TX. HIGHS ARE EXPECTED TO BE A TAD WARMER THAN YESTERDAY`S
VALUES. OVERALL FCST LOOKS ON TRACK WITH NO MAJOR CHANGES AT THIS
TIME. WILL UPDATE ZONES TO REMOVE MENTION OF MORNING FOG.
&&
.PREV DISCUSSION... /ISSUED 538 AM CST THU NOV 19 2015/
DISCUSSION...SEE AVIATION SECTION FOR 12Z TAFS.
AVIATION...ALTHOUGH THE TEMP/DEWPOINT SPREADS ARE NEAR ZERO FOR
THE COASTAL PLAINS...FOG HAS BEEN SLOW TO FORM WITH ONLY SPOTTY
OCCURRENCES OVER THE PAST COUPLE OF HOURS. WINDS ARE 5-7 KNOTS
FROM THE NORTH WHICH MAY KEEP FOG FROM FORMING. WILL KEEP A
TEMPO GROUP FROM 12-14Z FOR VCT FOR FOG/MVFR VSBYS. THEN CLEAR
SKIES AND VFR CONDITIONS FOR MOST OF THE DAY TODAY. CLOUDS
AROUND 6 KFT OVER THE GULF WATERS EAST OF THE LOWER TEXAS COAST
SHOULD MOVE NORTHWARD LATE THIS AFTERNOON AND REACH THE SOUTHERN
PARTS OF THE COASTAL BEND/BRUSH COUNTRY. MOISTURE ADVECTION IN
THIS LAYER WILL INCREASE TONIGHT WITH BROKEN CLOUD DECK NEAR
5 KFT REACHING LRD AT 04Z AND AT CRP BY 08Z.
PREV DISCUSSION... /ISSUED 339 AM CST THU NOV 19 2015/
SHORT TERM (TODAY THROUGH FRIDAY)...LIGHT NORTHEAST WINDS AND
NEAR ZERO TEMP/DEWPOINT SPREAD WILL LEAD TO A BRIEF POTENTIAL FOR
FOG OVER THE COASTAL PLAINS EARLY THIS MORNING. FOG HAS BEEN
REPORTED AT PORT LAVACA IN THE PAST HOUR. ONLY MODEL INDICATING
A STRONG INDICATOR FOR FOG IS THE LATEST RAP MODEL. WILL HAVE TO
WATCH TRENDS TO SEE IF FOG BECOMES DENSE OVER THE NEXT COUPLE OF
HOURS.
OTHERWISE...ANOTHER BENIGN WEATHER DAY IS EXPECTED. SURFACE HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL BUILD EASTWARD INTO THE
MID MISSISSIPPI RIVER VALLEY TODAY. WINDS WILL INCREASE FROM THE
EAST-NORTHEAST LATER TODAY. HIGH TEMPERATURES WILL BE NEAR OR
SLIGHTLY WARMER THAN YESTERDAY.
LOW LEVEL FLOW WILL VEER TO EAST-SOUTHEAST LATER TONIGHT AS LOW
PRESSURE DEEPENS LEE OF THE CENTRAL ROCKIES. LOW CLOUDS ARE
EXPECTED TO RETURN ALONG THE RIO GRANDE INTO THE BRUSH COUNTRY
LATE TONIGHT. LOW LEVEL FLOW WILL BECOME SOUTHERLY FRIDAY WITH
MOISTURE STEADILY INCREASING WITH MOSTLY CLOUDY SKIES EXPECTED.
WEAK ISENTROPIC LIFT WILL LEAD TO A SLIGHT CHANCE OF LIGHT RAIN
OVER THE COASTAL WATERS INTO THE COASTAL BEND BY THE AFTERNOON.
WENT NEAR OR SLIGHTLY BELOW COOLER NAM GUIDANCE FOR HIGHS.
MARINE...EAST-NORTHEAST FLOW IS EXPECTED TO INCREASE BY THIS
AFTERNOON OVER THE OFFSHORE WATERS TO SCEC LEVELS AND REMAIN
AT THIS STRENGTH THROUGH THE NIGHT. SWELLS OF 4 TO 5 FEET WITH
PERIOD OF 8 SECONDS ALONG WITH EAST-NORTHEAST WINDS WILL KEEP
A MODERATE RISK OF RIP CURRENTS ALONG THE COAST.
LONG TERM (FRIDAY NIGHT THROUGH THANKSGIVING DAY)...CHANCES FOR
RAIN INCREASE OUT AHEAD OF A SIGNIFICANT COLD FRONT DUE TO MOVE
THROUGH SOUTH TEXAS SATURDAY MORNING. EXPECT SCATTERED
SHOWERS...WITH BETTER CHANCES OVER THE MIDDLE TEXAS COAST WHERE LOW
LEVEL MOISTURE WILL HAVE A BETTER CHANCE AT POOLING BEFORE FROPA.
HIGHS ON SATURDAY WILL OCCUR IMMEDIATELY BEFORE THE FRONT
PASSES...WITH TEMPERATURES FALLING QUICKLY BEHIND THE FRONT. WINDS
WILL ALSO PICK UP SUBSTANTIALLY BEHIND THE FRONT...WITH SMALL CRAFT
ADVISORY CONDITIONS EASILY MET FROM FROPA ALL THE WAY THROUGH EARLY
SUNDAY. CAA WILL KEEP TEMPERATURES IN THE 50S ON SUNDAY...AND
READINGS WILL DIP INTO THE 40S AWAY FROM THE COAST MONDAY MORNING AS
HIGH PRESSURE BUILDS INTO THE REGION.
HIGH PRESSURE WILL BEGIN TO SLIDE OFF TO THE EAST LATE
MONDAY...INITIATING RETURN FLOW ALONG THE COASTAL BEND. A FEATURE OF
INTEREST WILL BE MOISTURE FROM AN EASTERN PACIFIC TROPICAL
SYSTEM...AND MEDIUM RANGE MODELS DISAGREE ON HOW MUCH OF THAT WILL
GET CAUGHT UP IN SOUTHWEST FLOW ALOFT. FOR NOW WILL FOLLOW A MIDDLE
ROAD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 81 61 77 67 70 / 0 0 20 40 50
VICTORIA 78 52 74 60 65 / 0 0 10 40 50
LAREDO 83 62 78 65 66 / 0 10 10 20 50
ALICE 82 58 78 65 68 / 0 0 20 30 50
ROCKPORT 80 62 76 66 70 / 0 0 20 40 50
COTULLA 81 56 76 62 64 / 0 0 10 20 50
KINGSVILLE 82 61 78 66 70 / 0 0 20 30 50
NAVY CORPUS 79 64 76 68 71 / 0 0 20 40 50
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TE/81...SHORT TERM
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
538 AM CST THU NOV 19 2015
.DISCUSSION...SEE AVIATION SECTION FOR 12Z TAFS.
&&
.AVIATION...ALTHOUGH THE TEMP/DEWPOINT SPREADS ARE NEAR ZERO FOR
THE COASTAL PLAINS...FOG HAS BEEN SLOW TO FORM WITH ONLY SPOTTY
OCCURRENCES OVER THE PAST COUPLE OF HOURS. WINDS ARE 5-7 KNOTS
FROM THE NORTH WHICH MAY KEEP FOG FROM FORMING. WILL KEEP A
TEMPO GROUP FROM 12-14Z FOR VCT FOR FOG/MVFR VSBYS. THEN CLEAR
SKIES AND VFR CONDITIONS FOR MOST OF THE DAY TODAY. CLOUDS
AROUND 6 KFT OVER THE GULF WATERS EAST OF THE LOWER TEXAS COAST
SHOULD MOVE NORTHWARD LATE THIS AFTERNOON AND REACH THE SOUTHERN
PARTS OF THE COASTAL BEND/BRUSH COUNTRY. MOISTURE ADVECTION IN
THIS LAYER WILL INCREASE TONIGHT WITH BROKEN CLOUD DECK NEAR
5 KFT REACHING LRD AT 04Z AND AT CRP BY 08Z.
&&
.PREV DISCUSSION... /ISSUED 339 AM CST THU NOV 19 2015/
SHORT TERM (TODAY THROUGH FRIDAY)...LIGHT NORTHEAST WINDS AND
NEAR ZERO TEMP/DEWPOINT SPREAD WILL LEAD TO A BRIEF POTENTIAL FOR
FOG OVER THE COASTAL PLAINS EARLY THIS MORNING. FOG HAS BEEN
REPORTED AT PORT LAVACA IN THE PAST HOUR. ONLY MODEL INDICATING
A STRONG INDICATOR FOR FOG IS THE LATEST RAP MODEL. WILL HAVE TO
WATCH TRENDS TO SEE IF FOG BECOMES DENSE OVER THE NEXT COUPLE OF
HOURS.
OTHERWISE...ANOTHER BENIGN WEATHER DAY IS EXPECTED. SURFACE HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL BUILD EASTWARD INTO THE
MID MISSISSIPPI RIVER VALLEY TODAY. WINDS WILL INCREASE FROM THE
EAST-NORTHEAST LATER TODAY. HIGH TEMPERATURES WILL BE NEAR OR
SLIGHTLY WARMER THAN YESTERDAY.
LOW LEVEL FLOW WILL VEER TO EAST-SOUTHEAST LATER TONIGHT AS LOW
PRESSURE DEEPENS LEE OF THE CENTRAL ROCKIES. LOW CLOUDS ARE
EXPECTED TO RETURN ALONG THE RIO GRANDE INTO THE BRUSH COUNTRY
LATE TONIGHT. LOW LEVEL FLOW WILL BECOME SOUTHERLY FRIDAY WITH
MOISTURE STEADILY INCREASING WITH MOSTLY CLOUDY SKIES EXPECTED.
WEAK ISENTROPIC LIFT WILL LEAD TO A SLIGHT CHANCE OF LIGHT RAIN
OVER THE COASTAL WATERS INTO THE COASTAL BEND BY THE AFTERNOON.
WENT NEAR OR SLIGHTLY BELOW COOLER NAM GUIDANCE FOR HIGHS.
MARINE...EAST-NORTHEAST FLOW IS EXPECTED TO INCREASE BY THIS
AFTERNOON OVER THE OFFSHORE WATERS TO SCEC LEVELS AND REMAIN
AT THIS STRENGTH THROUGH THE NIGHT. SWELLS OF 4 TO 5 FEET WITH
PERIOD OF 8 SECONDS ALONG WITH EAST-NORTHEAST WINDS WILL KEEP
A MODERATE RISK OF RIP CURRENTS ALONG THE COAST.
LONG TERM (FRIDAY NIGHT THROUGH THANKSGIVING DAY)...CHANCES FOR
RAIN INCREASE OUT AHEAD OF A SIGNIFICANT COLD FRONT DUE TO MOVE
THROUGH SOUTH TEXAS SATURDAY MORNING. EXPECT SCATTERED
SHOWERS...WITH BETTER CHANCES OVER THE MIDDLE TEXAS COAST WHERE LOW
LEVEL MOISTURE WILL HAVE A BETTER CHANCE AT POOLING BEFORE FROPA.
HIGHS ON SATURDAY WILL OCCUR IMMEDIATELY BEFORE THE FRONT
PASSES...WITH TEMPERATURES FALLING QUICKLY BEHIND THE FRONT. WINDS
WILL ALSO PICK UP SUBSTANTIALLY BEHIND THE FRONT...WITH SMALL CRAFT
ADVISORY CONDITIONS EASILY MET FROM FROPA ALL THE WAY THROUGH EARLY
SUNDAY. CAA WILL KEEP TEMPERATURES IN THE 50S ON SUNDAY...AND
READINGS WILL DIP INTO THE 40S AWAY FROM THE COAST MONDAY MORNING AS
HIGH PRESSURE BUILDS INTO THE REGION.
HIGH PRESSURE WILL BEGIN TO SLIDE OFF TO THE EAST LATE
MONDAY...INITIATING RETURN FLOW ALONG THE COASTAL BEND. A FEATURE OF
INTEREST WILL BE MOISTURE FROM AN EASTERN PACIFIC TROPICAL
SYSTEM...AND MEDIUM RANGE MODELS DISAGREE ON HOW MUCH OF THAT WILL
GET CAUGHT UP IN SOUTHWEST FLOW ALOFT. FOR NOW WILL FOLLOW A MIDDLE
ROAD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 81 61 77 67 70 / 0 0 20 40 50
VICTORIA 78 52 74 60 65 / 0 0 10 40 50
LAREDO 83 62 78 65 66 / 0 10 10 20 50
ALICE 82 58 78 65 68 / 0 0 20 30 50
ROCKPORT 80 62 76 66 70 / 0 0 20 40 50
COTULLA 81 56 76 62 64 / 0 0 10 20 50
KINGSVILLE 82 61 78 66 70 / 0 0 20 30 50
NAVY CORPUS 79 64 76 68 71 / 0 0 20 40 50
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TMT/89...AVIATION
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
344 PM EST THU NOV 19 2015
.SYNOPSIS...
20Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN AMPLIFIED UPPER
LEVEL PATTERN IN PLACE OVER THE CONUS...HIGHLIGHTED BY A BROAD
NEGATIVELY-TILTED LONGWAVE TROUGH. THIS TROUGH IS ANCHORED BY A
CLOSED LOW FEATURE SPINNING OVER THE UPPER MIDWEST. MOISTURE PLUME
ASSOCIATED WITH THE SOUTHERN STREAM JET IS WELL DEFINED ON WV
IMAGERY CROSSING THE GULF OF MEXICO AND OVER THE FLORIDA
PENINSULA. BEEN PLAYING CATCH-UP WITH THE FORECAST ALL DAY WITH
THIS PATTERN AS THE MODELS HAVE BEEN NOT HANDLING CERTAIN FEATURES
VERY WELL. SAW THE DEVELOPMENT OF A LEAF-CLOUD FEATURE OVER THE
FLORIDA PANHANDLE /NORTH-CENTRAL GULF OF MEXICO WITHIN THE
SOUTHERN STREAM MOISTURE PLUME THIS MORNING. THIS FEATURE IS THE
RESULT OF THE INTERACTION OF PASSING SHORTWAVE ENERGY (MOST
DEFINED ABOVE 500MB) WITH THE LOWER LEVEL FRONTAL BOUNDARY. THIS
CYCLOGENESIS CONTINUES TO NOT BE WELL REPRESENTED IN THE ENSEMBLE
GUIDANCE AND HENCE THE MODELS ARE GENERALLY TOO DRY AND HAVING
DIFFICULTY WITH THE HIGHER COVERAGE OF CONVECTION OVER THE
NORTHEAST GULF/NORTHERN FLORIDA.
FORECAST NOW HAS CATEGORICAL POPS AT 100% FOR THE ENTIRE NATURE
COAST WITH LIKELY/CATEGORICAL POPS DOWN EVEN INTO THE TAMPA BAY
AREA. THE SURFACE LOW DEVELOPMENT HAS SLOWED THE SOUTHWARD
PROGRESSION OF THE FRONT/BOUNDARY...AND THIS WILL ALLOW THE
CONTINUED CONVECTION OVER THE EASTERN GULF TO PROGRESS INLAND
ACROSS THE FLORIDA WEST COAST AS FAR SOUTH AS TAMPA BAY/MANATEE
COUNTY EARLY THIS EVENING.
SOUTH AND EAST OF TAMPA BAY...NOW SEEING DEVELOPMENT OF MORE
DIURNAL TYPE SCT SHOWERS WHICH SHOULD CONTINUE (AN EVEN INCREASE
IN COVERAGE SOMEWHAT) THROUGH THE MIDDLE EVENING HOURS.
HOWEVER...NOT EXPECTING ANY ORGANIZED OR LONG LASTING TYPE OF
RAINFALL FOR THIS PORTION OF THE FORECAST AREA.
&&
.SHORT TERM (TONIGHT THROUGH FRIDAY)...
TONIGHT... SHORTWAVE ENERGY PASSES OFF TO THE NORTHEAST ALLOWING
WHATEVER FRONTAL WAVE EXISTS TO OUR NORTH TO EXIT AND SWING THE
COLD FRONT DOWN THE PENINSULA. THIS PROGRESSION WILL SLOWLY
DECREASE RAIN CHANCES TO THE NORTH OF THE 1-4 CORRIDOR...WHILE AT
LEAST SCATTERED SHOWERS CONTINUE IN THE FORECAST FOR THE SOUTHERN
HALF OF THE AREA. BY DAWN THE FRONT LOOKS TO HAVE BECOME QUASI-
STATIONARY OVER SOUTH FLORIDA. ENOUGH DRY AIR ALOFT IS FORECAST BY
MOST GUIDANCE MEMBERS TO HAVE ADVECTED SOUTHWARD TO HOPEFULLY END
RAIN CHANCES NORTH OF TAMPA BAY BY DAWN. DESPITE THE COLD FRONTAL
PASSAGE DURING THE OVERNIGHT FOR MOST SPOTS...LOW TEMPERATURES
WILL REMAIN ABOVE NORMAL FOR MID NOVEMBER...RANGING FROM AROUND 60
IN THE FAR NORTH TO THE MID 60S/LOW 70S ELSEWHERE.
FRIDAY...RAIN CHANCES LOOK TO REMAIN VERY LOW TO THE NORTH OF THE
I-4 CORRIDOR THROUGHOUT FRIDAY AS DRY AIR ALOFT CONTINUE TO MOVE
DOWN FROM THE NORTH. AS ONE TRAVELS SOUTH FROM I-4...AVAILABLE
MOISTURE AND CLOSER PROXIMITY TO THE FRONTAL FORCING/CONVERGENCE
OVER SOUTH FLORIDA WILL INCREASE SHOWER CHANCES. THE LACK OF ANY
SUBSTANTIAL UPPER LEVEL SUPPORT SHOULD KEEP THE SHOWERS SCATTERED
WITH GENERALLY LIGHT QPF...HOWEVER...WOULD NOT ANTICIPATE MUCH IN
THE WAY OF SUN ON FRIDAY FROM THE I-4 CORRIDOR SOUTHWARD. A RATHER
CLOUDY PERIOD IS IN THE FORECAST...AND THAT TREND LOOKS TO
CONTINUE INTO THE UPCOMING WEEKEND...ALONG WITH HIGHER RAIN
CHANCES SURGING BACK NORTHWARD ON SATURDAY. MORE ON THE WEEKEND
FORECAST WITHIN THE LONG TERM DISCUSSION BELOW.
&&
.LONG TERM (FRIDAY NIGHT-THURSDAY)...
THE UPCOMING WEEKEND LOOKS TO BE ON THE WET SIDE BEFORE WE DRY UP
AND COOL OFF FOR EARLY NEXT WEEK. IN FACT...WE SHOULD SEE A COUPLE
OF DAYS OF BELOW-NORMAL TEMPERATURES BEFORE FINALLY GETTING
CLOSER TO NORMAL FOR THE MIDDLE PART OF THE WEEK.
AS FAR AS OUR WEEKEND WEATHER...RAIN CHANCES WILL BE ON THE RISE
THROUGH SATURDAY AND REMAIN IN THE CHANCE TO LIKELY RANGE THROUGH
SUNDAY AS UPPER-LEVEL SHORTWAVE ENERGY MOVES ACROSS THE GULF AND
THEN THE STATE THROUGH THE WEEKEND. AT THE SURFACE...THE STALLED
FRONTAL BOUNDARY ACROSS SOUTH FLORIDA WILL BE IN PLACE AND BOTH THE
GFS AND THE ECMWF TRY TO CLOSE OFF A LOW TO OUR NORTHEAST ON SUNDAY.
SEEING SOME MODEL DIFFERENCES AS FAR AS TIMING TO CLEAR EVERYTHING
OUT...WITH THE ECMWF A BIT ON THE SLOW SIDE. EITHER WAY...IT LOOKS
LIKE WE COULD STILL BE DEALING WITH SOME SHOWER ACTIVITY SUNDAY
NIGHT SO WILL LEAVE CHANCE POPS IN THE FORECAST.
WE SHOULD FINALLY CLEAR OUT DURING THE DAY ON MONDAY AS A FRONT
MOVES THROUGH AND THE COOLEST AND DRIEST AIR MASS WE HAVE SEEN SO
FAR THIS SEASON BEGINS TO MOVE INTO THE AREA. HIGH PRESSURE WILL
SETTLE INTO THE SOUTHEAST FOR MONDAY AND TUESDAY...WITH TEMPERATURES
BELOW NORMAL FOR BOTH DAYS. TUESDAY LOOKS TO BE THE COOLEST MORNING
THIS WEEK WITH LOWS IN THE LOWER 40S TO MID 50S. TEMPERATURES WILL
MODERATE CLOSER TO NORMAL VALUES FOR WEDNESDAY AND THURSDAY AS THE
HIGH SHIFTS NORTHEAST AND OUR WINDS BECOME MORE NORTHEASTERLY.
&&
.AVIATION...
VFR/MVFR CIGS CONTINUE ACROSS THE REGION THIS AFTERNOON. THE MOST
WIDESPREAD SHOWERS/RAINFALL IS NORTH OF THE TERMINALS...BUT RAIN
CHANCES WILL BE INCREASING FOR KPIE/KTPA/KLAL OVER THE NEXT
SEVERAL HOURS. TONIGHT...PERIODS OF MVFR CIGS/VIS LOOK PROBABLE
FOR ALL TERMINALS AS A WEAK COLD FRONT SETTLES SOUTH ACROSS THE
REGION.
&&
.MARINE...
A WEAKENING COLD FRONT SETTLES SOUTHWARD THROUGH THE EASTERN GULF
OF MEXICO TONIGHT. THIS FRONT WILL STALL OVER SOUTH FLORIDA BY
FRIDAY MORNING. A WEAK WAVE OF LOW PRESSURE NOW LOOKS TO RIDE
ALONG THIS FRONT AND THROUGH THE EASTERN GULF DURING THE UPCOMING
WEEKEND. IF THIS TREND CONTINUES...THE CHANCES FOR MORE WIDESPREAD
RAINFALL SATURDAY AND SUNDAY WILL BE INCREASING IN FUTURE
FORECASTS. HIGH PRESSURE WILL THEN BUILD IN FROM THE NORTH IN THE
WAKE OF THIS LOW LATE SUNDAY AND THROUGH THE EARLY PORTION OF NEXT
WEEK. MARINERS CAN EXPECT CAUTIONARY TO ADVISORY LEVEL NORTHEAST
FLOW ACROSS THE EASTERN GULF OF MEXICO DURING THE EARLY PORTION OF
NEXT WEEK.
&&
.FIRE WEATHER...
A WEAK COLD FRONT WILL CROSS THROUGH THE AREA TONIGHT AND STALL
OVER SOUTH FLORIDA ON FRIDAY. BEST CHANCE FOR SHOWERS WILL SINK
SOUTH WITH THE FRONT AND BE GENERALLY SOUTH OF THE I-4 CORRIDOR
FOR FRIDAY. ALTHOUGH SOME DRIER AIR WILL ARRIVE OVER THE NATURE
COAST...RELATIVE HUMIDITY VALUES ARE EXPECTED TO REMAIN ABOVE
CRITICAL LEVELS. HOWEVER...HIGH DISPERSION INDICES ARE FORECAST
ON FRIDAY FOR THE NATURE COAST ZONES. IT IS BECOME MORE LIKELY
THAT A WIDESPREAD RAIN EVENT WILL OCCUR ACROSS MUCH OF THE
REGION THIS WEEKEND...WHICH WILL PREVENT ANY FIRE WEATHER
CONCERNS.
FOG POTENTIAL...PATCHY FOG WILL BE POSSIBLE EACH NIGHT THROUGH
SUNDAY MORNING...HOWEVER NO SIGNIFICANT OR WIDESPREAD VISIBILITY
REDUCTIONS ARE EXPECTED THROUGH THE FORECAST PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 71 82 70 81 / 60 20 20 70
FMY 72 84 71 82 / 40 50 40 60
GIF 70 81 68 81 / 50 30 20 60
SRQ 70 82 70 81 / 50 30 30 70
BKV 67 80 66 82 / 60 20 10 60
SPG 71 82 70 80 / 60 20 20 70
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...BEACH HAZARDS STATEMENT THROUGH MONDAY EVENING FOR COASTAL
SARASOTA-PINELLAS.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/FIRE WEATHER...14/MROCZKA
LONG TERM...05/CARLISLE
MARINE...14/MROCZKA
AREA FORECAST DISCUSSION
NWS GOODLAND KS
116 PM MST THU NOV 19 2015
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 206 AM MST THU NOV 19 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOWS LONG FETCH OF NW
FLOW EXTENDING FROM THE PACIFIC NW ACROSS THE CENTRAL ROCKIES INTO
THE THE PLAINS...WITH SARGE TROUGH ALONG THE MISSISSIPPI RIVER
VALLEY. AT THE SURFACE HIGH PRESSURE IS IN PLACE.
SNOW PACK CONTINUES TO BE A CONSIDERATION THROUGH AT LEAST THE SHORT
RANGE PERIODS FOR T/TD...AND ADJUSTMENTS WERE MADE ACCORDINGLY.
TODAY-TONIGHT...PASSING HIGH CLOUDS ASSOCIATED WITH WEAK RIPPLES
WITHIN NW FLOW ALOFT WILL CONTINUE THROUGH TONIGHT. OTHERWISE DRY
CONDITIONS WILL PERSIST. A COOLER AIR MASS WILL REMAIN IN PLACE
AND TEMPERATURES WILL BE AT LEAST 5-15F COOLER THAN YESTERDAY
ESPECIALLY IF WE SEE MORE EXTENSIVE/OPAQUE CLOUD COVER.
FRIDAY-FRIDAY NIGHT...A STRONGER SHORTWAVE TROUGH/CLIPPER EMBEDDED
WITH NW FLOW WILL MOVE THROUGH THE REGION ALONG WITH ANOTHER COLD
FRONT (PASSING LATE AFTERNOON). MOISTURE ADVECTION IS LIMITED DUE TO
THE TRAJECTORY/TRACK OF THIS SYSTEM...HOWEVER THERE WILL BE ENOUGH
FORCING TO SUPPORT A FEW RAIN/SNOW SHOWERS OR SPRINKLES/FLURRIES
DURING THESE PERIODS. MODELS SHOWS VERY STRONG GRADIENT
ALONG/BEHIND FRONT HIGHLIGHTED BY 8-10 MB 3HR PRESSURE RISES (10-15
MB 6 HR PRESSURE RISES). ITS HARD TO TELL HOW DEEP WE WILL MIX AS
THERE COULD BE EXTENSIVE CLOUD COVER AND POSSIBLE INVERSION ABOVE
LINGERING SNOW PACK. IF WE WERE TO MIX TO 850 MB WE COULD SEE WINDS
45-50 MPH. WINDS ABOVE THIS LAYER ARE EVEN HIGHER...SO THIS WILL
NEED TO BE WATCHED IN THE EVENT SHOWERS HELP MIXING AND CREATE
ISOLATED 60 MPH DOWNBURST. INCREASING WAA AHEAD OF THIS FRONT
SHOULD ALLOW SOME LOCATIONS TO WARM INTO THE MID 50S BEFORE
TEMPERATURES START DECREASING IN THE AFTERNOON.
SATURDAY-SATURDAY NIGHT...ANOTHER SHORTWAVE TROUGH IS ADVERTISED TO
PASS THROUGH THE NORTHERN PLAINS...HOWEVER THIS FEATURE IS NOT QUITE
AS STRONG...AND MOISTURE PROFILES ARE EVEN LESS FAVORABLE. DRY
CONDITIONS SHOULD BE EXPECTED THOUGH THESE PERIODS. THIS SHORTWAVE
WILL ALSO HELP REINFORCE THE COOLER POST FRONT AIR MASS...SO HIGHS
IN THE 30S ARE EXPECTED ACROSS OUR CWA AND I COULD SEE SOME
LOCATIONS WITH HIGHS AROUND 32.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 103 PM MST THU NOV 19 2015
SHORTWAVE TROUGH DROPPING OUT OF THE NORTHERN ROCKIES WILL BRING
SCATTERED FLURRIES/CHANCE OF LIGHT SNOW FRIDAY NIGHT. SNOW AMOUNTS
WILL BE LESS THAN A HALF INCH AND IMPACTS ARE EXPECTED TO BE
MINIMAL. SHORTWAVE RIDGING WILL BUILD IN ITS WAKE OVER THE WEEKEND
AND INTO NEXT WEEK WITH DRY CONDITIONS. TEMPERATURES ON SATURDAY
WILL BE MUCH BELOW NORMAL THEN WARM TO SLIGHTLY BELOW NORMAL ON
SUNDAY AND SLIGHTLY ABOVE NORMAL ON MONDAY. TEMPERATURES WILL BE A
BIT COOLER IN AREAS WITH DEEPEST SNOW COVER. ANOTHER FAST MOVING
SHORTWAVE TROUGH MOVES ACROSS IN THE ZONAL FLOW ON TUESDAY BUT
APPEARS TO LACK SUFFICIENT MOISTURE FOR PRECIPITATION SO WILL KEEP
IT DRY. RIDGING REBUILDS FOR THE REMAINDER OF THE LONG TERM PERIOD
AHEAD OF A SYSTEM CUTTING OFF IN THE GREAT BASIN. IT MIGHT BRING A
CHANCE FOR RAIN OR SNOW BY THURSDAY AS IT KICKS OUT ACROSS THE
CENTRAL AND NORTHERN ROCKIES...BUT AS OF NOW MODELS ONLY SHOWING
VERY LIGHT ACCUMULATIONS OF AN INCH OR TWO IF ANY AT ALL. THE
TRACK OF THE UPPER LOW APPEARS TO BE TOO FAR NORTH FOR SIGNIFICANT
ACCUMULATIONS IN THE CENTRAL PLAINS. IT DOES HOWEVER LOOK LIKE IT
WILL TAP INTO MUCH COLDER AIRMASS AROUND THURSDAY OR THURSDAY
NIGHT...SO COULD BE SOME HIGHLY CHANGEABLE WEATHER AROUND THE
HOLIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 905 AM MST THU NOV 19 2015
KGLD...VFR THROUGH THE PERIOD. CLOUDINESS WILL GRADUALLY INCREASE
THROUGH THE PERIOD AS A WEATHER SYSTEM MOVES TOWARD THE AREA.
SOUTHWEST WINDS JUST UNDER 12KTS AT TAF ISSUANCE EXPECTED TO BACK
TO THE SOUTH LATE IN THE AFTERNOON AS SFC HIGH MOVES EAST AND LOW
PRESSURE DEEPENS ALONG THE FRONT RANGE. LITTLE CHANGE EXPECTED
OVERNIGHT. FOR FRIDAY WINDS VEER TO THE WEST NEAR 10KTS BY
MID MORNING THEN WEST-NORTHWEST AT THE TAIL END OF THE TAF PERIOD
AS A COLD FRONT APPROACHES FROM THE NORTHWEST.
KMCK...VFR THROUGH THE PERIOD. CLOUDINESS WILL GRADUALLY INCREASE
LATE THIS AFTERNOON/EARLY EVENING WITH A MOSTLY CLOUDY/CLOUDY SKY
EXPECTED OVERNIGHT THROUGH FRIDAY. SOUTHWEST WINDS AROUND 6KTS AT
TAF ISSUANCE EXPECTED TO BACK TO THE SOUTH NEAR 5KTS BY 00Z. A
LIGHT SOUTH-SOUTHEAST WIND EXPECTED OVERNIGHT THROUGH MID MORNING
BEFORE VEERING TO THE WEST AROUND 6KTS AT THE END OF THE TAF
PERIOD AS A COLD FRONT APPROACHES.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
905 AM MST THU NOV 19 2015
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 206 AM MST THU NOV 19 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOWS LONG FETCH OF NW
FLOW EXTENDING FROM THE PACIFIC NW ACROSS THE CENTRAL ROCKIES INTO
THE THE PLAINS...WITH SARGE TROUGH ALONG THE MISSISSIPPI RIVER
VALLEY. AT THE SURFACE HIGH PRESSURE IS IN PLACE.
SNOW PACK CONTINUES TO BE A CONSIDERATION THROUGH AT LEAST THE SHORT
RANGE PERIODS FOR T/TD...AND ADJUSTMENTS WERE MADE ACCORDINGLY.
TODAY-TONIGHT...PASSING HIGH CLOUDS ASSOCIATED WITH WEAK RIPPLES
WITHIN NW FLOW ALOFT WILL CONTINUE THROUGH TONIGHT. OTHERWISE DRY
CONDITIONS WILL PERSIST. A COOLER AIR MASS WILL REMAIN IN PLACE
AND TEMPERATURES WILL BE AT LEAST 5-15F COOLER THAN YESTERDAY
ESPECIALLY IF WE SEE MORE EXTENSIVE/OPAQUE CLOUD COVER.
FRIDAY-FRIDAY NIGHT...A STRONGER SHORTWAVE TROUGH/CLIPPER EMBEDDED
WITH NW FLOW WILL MOVE THROUGH THE REGION ALONG WITH ANOTHER COLD
FRONT (PASSING LATE AFTERNOON). MOISTURE ADVECTION IS LIMITED DUE TO
THE TRAJECTORY/TRACK OF THIS SYSTEM...HOWEVER THERE WILL BE ENOUGH
FORCING TO SUPPORT A FEW RAIN/SNOW SHOWERS OR SPRINKLES/FLURRIES
DURING THESE PERIODS. MODELS SHOWS VERY STRONG GRADIENT
ALONG/BEHIND FRONT HIGHLIGHTED BY 8-10 MB 3HR PRESSURE RISES (10-15
MB 6 HR PRESSURE RISES). ITS HARD TO TELL HOW DEEP WE WILL MIX AS
THERE COULD BE EXTENSIVE CLOUD COVER AND POSSIBLE INVERSION ABOVE
LINGERING SNOW PACK. IF WE WERE TO MIX TO 850 MB WE COULD SEE WINDS
45-50 MPH. WINDS ABOVE THIS LAYER ARE EVEN HIGHER...SO THIS WILL
NEED TO BE WATCHED IN THE EVENT SHOWERS HELP MIXING AND CREATE
ISOLATED 60 MPH DOWNBURST. INCREASING WAA AHEAD OF THIS FRONT
SHOULD ALLOW SOME LOCATIONS TO WARM INTO THE MID 50S BEFORE
TEMPERATURES START DECREASING IN THE AFTERNOON.
SATURDAY-SATURDAY NIGHT...ANOTHER SHORTWAVE TROUGH IS ADVERTISED TO
PASS THROUGH THE NORTHERN PLAINS...HOWEVER THIS FEATURE IS NOT QUITE
AS STRONG...AND MOISTURE PROFILES ARE EVEN LESS FAVORABLE. DRY
CONDITIONS SHOULD BE EXPECTED THOUGH THESE PERIODS. THIS SHORTWAVE
WILL ALSO HELP REINFORCE THE COOLER POST FRONT AIR MASS...SO HIGHS
IN THE 30S ARE EXPECTED ACROSS OUR CWA AND I COULD SEE SOME
LOCATIONS WITH HIGHS AROUND 32.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 206 AM MST THU NOV 19 2015
NORTHWEST FLOW ALOFT REMAINS OVER THE REGION ON SUNDAY BEFORE AN
UPPER RIDGE OVER THE WESTERN CONUS FLATTENS OUT OVER THE HIGH PLAINS
ON MONDAY AND TUESDAY. THIS PATTERN WILL BRING DRY CONDITIONS AND
WARMER TEMPERATURES TO THE FORECAST THROUGH EARLY NEXT WEEK.
GUIDANCE IS SHOWING AN UPPER LOW MOVING OVER THE PACIFIC NORTHWEST
TUESDAY NIGHT. DRY CONDITIONS CONTINUE FOR THE AREA ON WEDNESDAY
AHEAD OF THIS SYSTEM AS IT TRAVELS EASTWARD TOWARDS THE PLAINS WITH
THE ASSOCIATED COLD FRONT LOOKING TO PASS THROUGH THE REGION BY
THURSDAY. COULD SEE PRECIP CHANCES LATER NEXT WEEK WITH THIS SYSTEM.
EXPECT TEMPERATURES TO WARM INTO EARLY NEXT WEEK WITH HIGHS IN THE
40S ON SUNDAY GRADUALLY INCREASING INTO THE 50S BY TUESDAY BEFORE
COOLING INTO THE UPPER 40S TO MID 50S FOR WEDNESDAY. CONTINUED TO
KEEP THE COOLER TEMPERATURES IN AREAS WHERE SNOWPACK MAY STILL BE
PRESENT. HOWEVER...SUSPECT MELTING WILL OCCUR BEFORE THE END OF THIS
PERIOD. LOWS WILL GENERALLY BE IN THE 20S. THE REGION COULD SEE A
BLAST OF COLD AIR TOWARDS THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 905 AM MST THU NOV 19 2015
KGLD...VFR THROUGH THE PERIOD. CLOUDINESS WILL GRADUALLY INCREASE
THROUGH THE PERIOD AS A WEATHER SYSTEM MOVES TOWARD THE AREA.
SOUTHWEST WINDS JUST UNDER 12KTS AT TAF ISSUANCE EXPECTED TO BACK
TO THE SOUTH LATE IN THE AFTERNOON AS SFC HIGH MOVES EAST AND LOW
PRESSURE DEEPENS ALONG THE FRONT RANGE. LITTLE CHANGE EXPECTED
OVERNIGHT. FOR FRIDAY WINDS VEER TO THE WEST NEAR 10KTS BY
MID MORNING THEN WEST-NORTHWEST AT THE TAIL END OF THE TAF PERIOD
AS A COLD FRONT APPROACHES FROM THE NORTHWEST.
KMCK...VFR THROUGH THE PERIOD. CLOUDINESS WILL GRADUALLY INCREASE
LATE THIS AFTERNOON/EARLY EVENING WITH A MOSTLY CLOUDY/CLOUDY SKY
EXPECTED OVERNIGHT THROUGH FRIDAY. SOUTHWEST WINDS AROUND 6KTS AT
TAF ISSUANCE EXPECTED TO BACK TO THE SOUTH NEAR 5KTS BY 00Z. A
LIGHT SOUTH-SOUTHEAST WIND EXPECTED OVERNIGHT THROUGH MID MORNING
BEFORE VEERING TO THE WEST AROUND 6KTS AT THE END OF THE TAF
PERIOD AS A COLD FRONT APPROACHES.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...99
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
104 PM EST THU NOV 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER SOUTHEAST CANADA WILL SLIDE EAST TODAY AS A
COLD FRONT APPROACHES FROM THE WEST. THE FRONT CROSSES THE AREA
THIS EVENING...WITH HIGH PRESSURE BUILDING IN FRIDAY AND
SATURDAY. A DRY COLD FRONT WILL MOVE ACROSS THE REGION SATURDAY
NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST GOES WATER VAPOR IMAGERY DEPICTS MOISTURE PLUME LIFTING ALONG
THE SE COASTAL PLAIN INTO THE LOCAL AREA DOWNSTREAM OF A POTENT NRN
STREAM CLOSED LOW OVER SOUTH CENTRAL CANADA. AT THE SFC...COLD FRONT
HAS LOCATED OVER THE CENTRAL APPALACHIANS WITH A WARM FRONT OVER NC.
SHOWER COVERAGE HAS DIMINISHED THIS MORNING...WITH THE BEST COVERAGE
OVER SOUTHERN VA AND NE NC. ELSEWHERE...SHOWERS HAVE BECOME MORE
SCATTERED IN NATURE. FEW LIGHTNING STRIKES WERE OBSERVED OVER
MECKLENBURG COUNTY WHERE RAP GUIDANCE INDICATES SLIGHTLY STEEPER MID
LEVEL LAPSE RATES TO GO ALONG WITH <250 J/KG MUCAPE...BUT HAS SINCE
DIMINISHED. DO NOT ANTICIPATE MORE THAN ISOLATED/EMBEDDED RUMBLE OF
THUNDER BASED ON VERY LITTLE INSTABILITY...BUT WILL MAINTAIN SLIGHT
CHANCE THUNDER WORDING IN FORECAST.
FOR THE REST OF THE DAY...SHORTWAVE ENERGY PUSHES OFFSHORE AS THE
COLD FRONT SLOWLY CROSSES THE REGION. SWLY FLOW ALOFT WILL
PERSIST...BUT BEST MOISTURE PUSHES EAST OF INTERSTATE 95 BY EARLY
AFTERNOON LEAVING ONLY SCATTERED SHOWERS OVER THE PIEDMONT INTO
CENTRAL VA. ISENTROPIC LIFT INDICATED IN NAM12 THETA SURFACES WILL
LIKELY RESULT IN INCREASING COVERAGE ALONG THE COAST AS THE SHOWERS
FROM NC LIFT INTO THE ERN AREA. WILL MAINTAIN LIKELY TO CATEGORICAL
POPS EAST OF INTERSTATE 95. ADDITIONAL QPF AMOUNTS WILL RANGE FROM A
LESS THAN QUARTER OF AN INCH WEST TO HALF AN INCH EAST. HIGHEST
AMOUNTS IN THE SOUTHEAST WHERE AREAS COULD SEE UP TO AN INCH. HIGHS
GENERALLY IN THE UPPER 60S TO LOW 70S. WILL BEGIN TO SEE BREAKS IN
THE CLOUDS LATE TODAY OVER THE PIEDMONT...PERHAPS INTO CENTRAL VA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
COLD FRONT PROGGED INVOF CHES BAY BY 00Z FRI THEN QUICKLY MOVES
OFFSHORE BY 06Z. THUS...SLGT CHANCE-CHANCE EVENING POPS WILL BE
MAINTAINED MAINLY EAST OF I-95 TO CHES BAY...WITH LIKELY POPS
NEAR THE COAST. ENOUGH MOISTURE NOTED TO KEEP SLIGHT CHANCE POPS
NEAR THE COAST AFTER MIDNIGHT. OTHERWISE...TSCTNS SHOW COLUMN
DRYING WHICH SHOULD RESULT IN DECREASING CLOUDINESS WEST OF THE
BAY. CAA SETS IN AS WINDS SHIFT TO THE NW. LOWS DROP BACK INTO THE
40S WRN HALF OF FA...50-55 ALONG THE COAST.
HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST FRI INTO SAT.
STRONG SUBSIDENCE RESULTS IN MAINLY CLEAR SKIES ALONG WITH A RETURN
TO NEAR NORMAL TEMPS. RATHER BREEZY FRI...ESPECIALLY ALONG THE
COAST. HIGHS FRI UPPER 50S TO LOWER 60S. LOWS FRI NIGHT LOWER 30S
NW TO LOWER 40S SERN COASTAL AREAS. HIGHS SAT IN THE MID-UPPER
50S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
OVERALL HAVE GOOD MODEL AGREEMENT FROM SUNDAY THROUGH
NEXT WEDNESDAY AS ONE COLD FRONT SWEEPS ACROSS THE MID ATLANTIC
REGION LATE SATURDAY NIGHT AND THEN HIGH PRESSURE MOVES INTO THE
AREA AND LINGERS THROUGH MID WEEK. THE 12Z GFS WAS MORE AGGRESSIVE
PUSHING THE FRONT OFF THE COAST AND ALSO IS A LITTLE COLDER WITH
850 TEMPS FALLING TO AROUND -10C AROUND 06Z MONDAY BEFORE THE AIR
MASS MODIFIES. THE 12Z ECMWF SLOWS THE PUSH OF THE COLDER AIR AND
ACTUALLY KEEPS IT FURTHER TO THE NORTH AND ALLOWS FOR MORE NELY
FLOW. IN SPITE OF THESE DIFFERENCES...THE FORECAST GENERALLY SHOWS
DRY AND COOL WEATHER FROM SUNDAY INTO WEDNESDAY. THE COLD FRONT IS
EXPECTED TO GO THROUGH DRY AS THE INITIAL BOUNDARY THAT GOES
THROUGH ON THURSDAY SUPPRESSES THE GULF MOISTURE AND WITH THE
WEST TO EAST MOVEMENT OF THE FRONT...ANY MOISTURE SHOULD BE RUNG
OUT AS THE BOUNDARY CROSSES THE MOUNTAINS. EXPECT A COLDER AND
WINDIER DAY ON SUNDAY AS THE TIGHTENING PRESSURE GRADIENT AND COLD
AIR ALOFT ALLOW FOR GOOD MIXING. AFTER A COLD NIGHT SUNDAY
NIGHT (WHICH COULD SEE WIDESPREAD FREEZING TEMPS)...EXPECT TO SEE
A GRADUAL WARMING TREND AS THE SFC HIGH SLOWLY MOVES OFF TO THE
EAST AND THE COLD AIR RETREATS BACK NORTH.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
COLD FRONT STILL WEST OF THE MTS WITH A WARM FRNT MOVG NORTH
ACROSS NC AT 18Z. STILL PLNTY OF MSTR AHEAD OF THE CDFRNT AND
MODELS CONT TO SHOW AREAS OF RAIN MOVG ACROSS THE RGN FOR THE
NEXT 6-9 HRS. HIGH RES DATA SUGGESTS A LINE OF CONVECTION MAY TRY
TO DVLP TOWARDS SUNSET MAINLY EAST OF I95 THEN MOVE EAST MOVG OFF
THE COAST BY 03Z. THUS...CONTINUED THE IFR/MVFR CIGS WITH TEMPO
GROUP FOR IFR VSBYS IN RAIN NEXT SVRL HRS. BEST TIMING FOR ANY
THUNDER ACROSS SERN TAF SITES WILL BE AFTR 21Z...BUT CONFIDENCE
NOT HIGH ENUF TO INCLUDE THUNDER IN THE TAFS. MAY END UP BEING
SHWRS WITH LCLLY HVY RAINFALL AS INSTABILITY LOOKS MARGINAL AT
BEST.
CDFRNT EXITS OFF THE COAST LATE THIS EVENING WITH TSCTNS SHOWING
RAPID COLUMN DRYING. THUS EXPECT A RATHER QUICK JUMP INTO VFR CIGS
THEN CLEARING AFTR 06Z. GUSTY S-SE WINDS BTWN 15-25 KTS THIS AFTRN
ALONG THE COAST WILL ACTUALLY DMNSH THIS EVENING BEFORE SHIFTING
TO THE NNW LATE TONIGHT THEN BECOME GUSTY ONCE AGAIN. DATA SUPPORTS
GUSTS BTWN 25-30 KTS FRI MORNING ACROSS SERN TAF SITES.
OUTLOOK...ANOTHER FRONT BRINGS STRONGER N-NW WINDS INTO SUN ALTHOUGH
IT LOOKS TO STAY DRY.
&&
.MARINE...
GIVEN THE RAPID INCREASE IN S-SE WINDS ACROSS THE LWR CHES BAY
PAST FEW HRS...WENT AHEAD AND STARTED THE SCA HEADLINE FOR THE LWR
JAMES RIVER WITH THE 1 PM UPDATE. STILL EXPECT A LULL IN THE WINDS
THIS EVENING BEFORE THE CAA SETS IN LATER TONITE.
PVS DSCN:
SE WNDS STEADILY INCRSG ATTM...STILL MNLY BLO SCA BUT W/ CDFNT
APPROACHING FM W AND PRES GRADIENT TIGHTEN UP A BIT MORE...CONTD
STRENGTHENING XPCD. THE PERSISTENT ESE FLO OVR THE WRN ATLC HAS
KICKED SEAS UP TO 5 TO 7 FT IN THE CSTL WTRS AND 3 TO 4 FT IN THE
LWR BAY. GUSTY SE WNDS CONT INTO THIS AFTN...THEN THE CDFNT
CROSSES THE WTRS THIS EVE W/ A BRIEF 4 TO 8 HR WEAKENING OF THE
WINDS BEFORE THE COLDER AIR ALOFT HITS THE WTRS AFT 06Z/20 W/ A
NNW SURGE OF 20 TO 30 KT (MAYBE BRIEF GALE GUSTS...ESP ON THE OCN
CENTERED ON 12Z/20). XPCG THIS SURGE TO LINGER INTO FRIDAY
AFTERNOON BEFORE WEAKENING AS SFC HI BUILDS INTO THE RGN FM THE W.
FOR THE WEEKEND...SHOULD SEE BENIGN CONDITIONS ON SATURDAY AS HIGH
PRESSURE IS IN PLACE AND THE WIND WEAKENS TO 5 TO 10 KT...EXPECT
THE SEAS TO GRADUALLY DIMINISH AS WELL. THE FLOW WILL TURN SW ON
SATURDAY NIGHT AS ANOTHER COLD FRONT SWEEPS THROUGH THE AREA. THE
MODELS SHOW ANOTHER STRONG SURGE OF COLD AIR BEHIND THIS FRONT SO
EXPECT THE WIND AND SEAS TO PICK UP ONCE AGAIN WITH SCA EXPECTED.
BY EARLY NEXT WEEK...HIGH PRESSURE ONCE AGAIN BUILDS OVER THE
WATERS AND CONDITIONS SHOULD IMPROVE ONCE AGAIN.
&&
.TIDES/COASTAL FLOODING...
LEVELS ACROSS THE LWR MD ERN SHORE TOPPED OUT BLO MINOR FLOODING
THRESHOLDS THIS MORNING AS IT APPEARS WINDS WERE TO LIGHT. GIVEN
THE INCREASE IN WINDS THIS AFTRN AND EVENING...WATER LEVELS ARE
EXPECTED TO COME CLOSE TO MINOR FLOODING THRESHOLDS ALONG THE BAY
SIDE OF THE LOWER MD ERN SHORE AS WELL AS TIDAL POTOMAC LOCATIONS
OF THE NORTHERN NECK CONCURRENT WITH TONIGHTS HIGH TIDE CYCLES.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO NOON EST FRIDAY FOR
ANZ635>637.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY UNTIL NOON EST FRIDAY FOR ANZ638.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ650-652-
654-656-658.
&&
$$
SYNOPSIS...MAS
NEAR TERM...MAS/SAM
SHORT TERM...MAS/MPR
LONG TERM...ESS
AVIATION...MPR
MARINE...MPR
TIDES/COASTAL FLOODING...MPR
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1247 PM EST THU NOV 19 2015
.SYNOPSIS...
THIS AFTERNOON WILL BE MILD AND SHOWERY, JUST AHEAD OF AN
APPROACHING COLD FRONT. ONCE THE FRONT PASSES THE REGION THIS
EVENING, DRIER WEATHER, ALONG WITH CHILLIER, MORE SEASONABLE
TEMPERATURES, WILL FOLLOW OVERNIGHT AND FRIDAY. OUR NEXT CHANCE
FOR SHOWERS IS EXPECTED FOR LATER SATURDAY, AS ANOTHER COLD FRONT
MOVES IN FROM THE NORTHWEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR SHOWS PATCHY AREAS OF RAIN SHOWERS WORKING NORTH TO
NORTHEAST ACROSS CENTRAL NY AND NORTHEAST PA. MODELS AND SPC
MESOANALYSIS PAGE SHOW A LOW-LEVEL JET FROM 50-65 KNOTS ACROSS
CENTRAL AND WESTERN NY AT THIS TIME. THIS LOW-LEVEL JET IS
PROGGED TO TRACK EAST REACHING THE I-81 CORRIDOR BY 18Z AND ERN
NY/WRN NEW ENGLAND BY 00Z AS A CD FRNT PUSHES INTO C NY.
STRONG LOW-LEVEL MOISTURE ADVECTION WILL CONTINUE TO LEAD TO
DESTABLIZATION FORMING SHOWERS AS IT WORKS E. THERE WAS A
TOPOGRAPHICAL COMPONENT TO THE PRECIPITATION AS UPSLOPE AREAS ON
THE STRG SOUTHERLY WINDS WERE SEEING MORE PRECIPITATION COVERAGE
THAN DOWNSLOPE AREAS. HENCE SHOWERS WERE MOST EXTENSIVE IN PARTS
OF NE PA AND NRN NY. USED HRRR RADAR FIELDS TO POPULATE POP GRIDS
THROUGH THE AFTERNOON WHICH ARE IN GOOD AGREEMENT WITH ON-GOING
PRECIP AND TERRAIN EFFECTS.
MODEL SOUNDINGS INTO THE EARLY AFTERNOON SHOW STRONG WINDS OF ABT
50 KNOTS OR SO DOWN TO ABOUT 2000 FEET AGL...THEN THE WINDS
RAPIDLY WEAKEN TO THE SFC LAYER. IRIS MESONET OBS SHOW A FEW
STATIONS WITH GUSTS OVER 40 MPH WITH THE VAST MAJORITY OF STATIONS
IN THE 30S MPH INCLUDING OUR MAJOR AIRPORTS. HENCE IT WILL BE
WINDY BUT BELOW WIND ADVY CRITERIA. AS THE LLJ WORKS E THIS
AFTERNOON WINDS WILL SLACKEN. WILL ISSUE SPS TO COVER FOR OUR NRN
COUNTIES.
WATER VAPOR IMAGERY SHOWS A SHORT WAVE TROF AXIS FROM IA/IL TO THE
DEEP SOUTH WHICH WILL SWING NE LATER THIS AFTERNOON AND EVENING
AND RE-ORGANIZE PRECIP MAINLY E OF I-81 AS IT WORKS NE AHEAD OF
CD FRNT THAT REACHES THE I-81 CORRIDOR BY 00Z. HENCE HAVE CAT
POPS TRACKING NE ACRS NE PA TO CATSKILLS LATER TODAY AND THIS
EVENING.
AFTER THIS WAVE PASSES OVERNIGHT PRECIP WINDS DOWN AND A
SECONDARY CD FRNT MOVES THROUGH WITH A RETURN TO MORE SEASONALLY
CHILLY TEMPERATURES BY FRI AM.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
3 AM UPDATE... A RELATIVELY QUICK EXIT OF THE STEADIER RAINFALL IS
ANTICIPATED THIS EVENING, AS THE SURFACE FRONT SWEEPS TO OUR EAST.
BEHIND THE FRONT, DRY ADVECTION/SINKING MOTION SHOULD LEAD TO AT
LEAST PARTIAL CLEARING FOR MOST OF THE FORECAST AREA. LOWS BY
DAYBREAK SHOULD RANGE FROM THE MID 30S-LOWER 40S.
FRIDAY-SATURDAY LOOKS GENERALLY DRY, AS A SURFACE HIGH AND SHORT-
WAVE RIDGING ALOFT SLIDE ACROSS NY/PA. TEMPERATURES WILL BE
SEASONABLY CHILLY, WITH HIGHS BOTH DAYS MAINLY IN THE 40S, AND
LOWS FRIDAY NIGHT MOSTLY IN THE 20S.
OUR NEXT WEATHER MAKER, IN THE FORM OF ANOTHER COLD FRONTAL
BOUNDARY, WILL BRING A CHANCE OF SHOWERS BY SATURDAY EVENING, AS
IT MOVES IN FROM THE WEST. LATER SATURDAY NIGHT OR EARLY SUNDAY
MORNING, ENOUGH COLD AIR ADVECTION MAY DEVELOP BEHIND THIS SYSTEM,
TO BRING LAKE-EFFECT SNOW SHOWERS TO UPSTATE NY, PERHAPS
IMPACTING SOME OF OUR NORTHERN ZONES. AS FRONTAL TIMING, ALONG
WITH FLOW ORIENTATION AND THE DEGREE OF COOLING POST FRONTAL
PASSAGE, BECOME CLEARER IN THE COMING DAYS, FORECAST DETAILS WILL
ALSO GET FIRMED UP IN THIS REGARD.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
345 AM UPDATE... COLD CYCLONIC FLOW WILL BE WITH US TO START THE
PERIOD SUNDAY, WITH MODEL CONSENSUS 850 MB TEMPERATURES DIPPING
TO -10 TO -12C. THIS SHOULD BE SUFFICIENTLY COLD FOR LAKE-EFFECT
SNOW SHOWERS. EARLY INDICATIONS ARE THAT THE PREVAILING FLOW
DIRECTION WILL BE DUE WESTERLY, PROBABLY KEEPING THE MOST
PERSISTENT ACTIVITY JUST NORTH AND WELL WEST OF OUR FORECAST
AREA. AT THIS JUNCTURE, WE HAVE A CHANCE OF RAIN/SNOW SHOWERS FOR
OUR NORTHERN/FAR WESTERN ZONES, WITH LIKELY PROBABILITIES UP OVER
NORTHERN ONEIDA COUNTY. SOME ACCUMULATIONS ARE CERTAINLY
POSSIBLE, ESPECIALLY ACROSS THE HIGHER TERRAIN. ONCE SMALLER-SCALE
DETAILS, SUCH AS EXACT LOW-LEVEL WIND DIRECTIONS, BECOME MORE
CERTAIN, SO WILL THE POTENTIAL FOR ANY SNOW ACCUMULATIONS.
NEXT WEEK, THERE IS FAIRLY GOOD MODEL AGREEMENT THAT HEIGHTS WILL
RISE OVER TIME ACROSS THE EASTERN U.S., AS A DEEP TROUGH/CLOSED
LOW DIGS INTO THE INTERMOUNTAIN WEST. THIS EVOLUTION SHOULD LEAD
TO MODERATING TEMPERATURES, LIKELY REACHING LEVELS ABOVE NORMAL
AGAIN, AS WE HEAD TOWARDS THE THANKSGIVING HOLIDAY PERIOD.
FAST MOVING, NORTHERN STREAM UPPER WAVES, COULD BRING SOME
RESIDUAL RAIN/SNOW SHOWERS MONDAY INTO EARLY TUESDAY. OTHERWISE,
MUCH OF NEXT WEEK LOOKS DRY, UNDERNEATH A BUILDING RIDGE ALOFT (AS
ALLUDED TO ABOVE).
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
TROF WILL PUSH THRU THE AREA SHRTLY BRINGING INCRSD VSBY AND
CIGS...AND A WIND SHFT TO A MORE SWLY FLOW...AND A BIT GUSTY. COLD
FNT WILL FOLLOW ARND 00Z BRINGING VFR CONDS AND ANOTHER WIND SHFT
TO A MORE WLY AND EVENTUALLY NW FLOW...WITH CONTD GUSTS.
SO...MVFR AND SPOTTY IFR CONDS ATTM WILL IMPROV THRU THE FIRST SIX
HRS OF THE TAF PD...FLWD BY GNRL VFR CONDS WITH GUSTY WINDS THRU
THE END OF THE TAF PD.
.OUTLOOK...
FRI NGT-SAT...VFR.
SAT NGT...COLD FRONTAL PASSAGE WITH RAIN SHOWERS CHANGING TO SNOW
SHOWERS...AND ASSOCIATED POSSIBLE RESTRICTIONS.
SUN THRU MON...RESTRICTIONS AT TIMES IN MIXED SHSN AND
SHRA...MAINLY CENTRAL NY TERMINALS.
TUE...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/MLJ
NEAR TERM...DJN
SHORT TERM...MLJ
LONG TERM...MLJ
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
100 PM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL CROSS CENTRAL NORTH CAROLINA LATE THIS
AFTERNOON AND EARLY THIS EVENING. HIGH PRESSURE WILL BUILD OVER THE
REGION ON FRIDAY. ANOTHER MAINLY DRY COLD FRONT WILL SWEEP ACROSS
THE AREA LATE SATURDAY NIGHT. COOL HIGH PRESSURE RETURNS SUNDAY...
LASTING THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 AM THURSDAY...
WIDESPREAD MODERATE SHOWERS WITH EMBEDDED STORMS PERSIST OVER THE
ERN CWA. PONDING OF WATER ON STREETS AND OTHER FLOODING OF URBAN AND
LOW LYING AREAS HAS BEEN COMMON WITH RAINFALL RATES UP TO 1-2" PER
HOUR. INSTABILITY THUS FAR HAS BEEN MEAGER... ALTHOUGH MUCAPE VALUES
OF 100-250 J/KG (WHICH APPEARS TO BE MOSTLY RESTRICTED TO THE MID
AND HIGH LEVELS) COMBINED WITH STRONG FOCUSED UPPER DIVERGENCE HAS
BEEN SUFFICIENT FOR NUMEROUS LIGHTNING FLASHES (MOSTLY POSITIVE
STRIKES) WITHIN THE HEAVIER SHOWERS. LOW LEVEL SHEAR OF 30-40 KTS
HERE WITH 0-1 SRH VALUES OVER 300 M2/S2 WARRANTS CLOSE MONITORING
FOR ANY ENHANCED WIND SIGNATURES OR WEAK ROTATION OVER OUR SE OVER
THE NEXT FEW HOURS. OTHERWISE... WINDS ALOFT WILL SLOWLY VEER TO
MORE SW AS THE 850-700 MB TROUGH AXES ROTATE NE THROUGH ERN NC...
AND AS THE VERY HIGH PW AND LOW LEVEL MOISTURE TRANSPORT TRANSLATE
SLOWLY NORTHEASTWARD INTO THE AFTERNOON... RAINFALL WILL SLOWLY
TAPER DOWN FROM WEST TO EAST. WATER VAPOR IMAGERY SHOWS A VERY
PRONOUNCED BACK EDGE TO THE DEEPER MOISTURE BUT WITH A STEERING FLOW
HOLDING ROUGHLY PARALLEL TO THE SURFACE FRONTAL ZONE (WHICH IS
ANALYZED OVER FAR WRN NC) AND ANOTHER MID LEVEL VORTICITY LOBE STILL
TO COME THROUGH THIS AFTERNOON... IT WILL TAKE UNTIL LATER TODAY FOR
THE SURFACE FRONTAL ZONE TO BE PROPELLED NORTHEASTWARD THROUGH
CENTRAL NC. LOW LEVEL MOISTURE SHOULD HOLD OVER MUCH OF CENTRAL NC
BEHIND THE MAIN RAIN SHIELD WITH A DELAY IN DOWNSLOPE LOW LEVEL
FLOW... WHICH WILL KEEP A CHANCE OF SHALLOW SHOWERS AREAWIDE THROUGH
MUCH OF THE AFTERNOON... ALONG WITH A BRIEF FOG THREAT WHERE SURFACE
WINDS EAST OF THE MOUNTAINS BECOME LIGHT AND VARIABLE FOR A TIME
AHEAD OF THE FRONT. EXPECT HIGHS FROM AROUND 70 TO THE MID 70S... IN
LINE WITH HI-RES RAPID UPDATE GUIDANCE. -GIH
PREVIOUS DISCUSSION AS OF 410 AM THURSDAY: A LARGE AREA OF RAIN...
WITH A FEW EMBEDDED CONVECTIVE ELEMENTS...IS CURRENTLY TRANSLATING
EAST ACROSS THE FORECAST AREA AS A 50KT PREFRONTAL LOW-LEVEL JET
LIFTS NORTH TOWARD THE MID-ATLANTIC STATES 9PER REGIONAL VWP). THE
CONVECTIVE ELEMENTS LACK ANY LIGHTNING OR STRONG WIND SIGNATURES...
AND GIVEN THE LACK OF ANALYZED INSTABILITY NORTH OF THE SAVANNAH
RIVER BASIN...WE MAY BE FREE OF THUNDERSTORMS FOR THE EARLY MORNING
HOURS. LATER THIS MORNING...VEERING SURFACE WINDS AHEAD OF THE MAIN
COLD FRONT...WHICH IS CURRENTLY MOVING THROUGH NORTHERN GEORGIA AND
EASTERN TN/KY...SHOULD TAP INTO NEAR 70 DEWPOINT AIR OVER EAST-
CENTRAL SC AND LEAD TO SOME WEAK DESTABILIZATION (250-500 J/KG
MLCAPE) FROM THE SANDHILLS INTO THE COASTAL PLAIN BY MIDDAY. THERE
IS NO REAL CONSENSUS IN NEAR TERM GUIDANCE REGARDING THE COVERAGE OF
ADDITIONAL SHOWERS AND STORMS...SOME SHOW A BROKEN LINE AND SOME
SHOW JUST SCATTERED CONVECTION. THE BACK EDGE TO THE DEEP MOISTURE
IS RAPIDLY PUSHING EAST ACROSS THE MOUNTAINS AND IS OUTPACING THE
COLD FRONT....SO DEEP MOISTURE WILL BE LACKING BY THE TIME THE FRONT
ARRIVES. HOWEVER...THE RAP SHOWS A PRE-FRONTAL TROUGH THAT MAY
PROVIDE A FOCUS FOR SOME SCATTERED CONVECTION...MAINLY US 1 AND EAST
BY MIDDAY...AND A FEW ADDITIONAL SHOWERS EVEN POSSIBLE WITH THE
PRIMARY COLD FRONT LATER THIS AFTERNOON AND EVENING. IF SOME
MODERATELY DEEP CONVECTION CAN INITIATE TODAY...0-6KM BULK SHEAR
VALUES OF 35-45KT WOULD CERTAINLY SUPPORT A DAMAGING WIND THREAT.
HIGHS WILL CLIMB BACK INTO THE MID 70S IN MOST AREAS...PARTICULARLY
IN THE WEST BEHIND THE CLEARING BUT AHEAD OF THE FRONT.
THE COLD FRONT WILL SWEEP ACROSS THE AREA BY EARLY EVENING...LEADING
TO COLD ADVECTION FOR MOST OF THE OVERNIGHT PERIOD AND LOWS DROPPING
INTO THE 40S FOR MOST OF CENTRAL NC.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 345 AM THURSDAY...
BENEATH BRIEF HEIGHT RISES IN BROAD WSW FLOW ALOFT... CONTINENTAL
POLAR HIGH PRESSURE AND AN ASSOCIATED DEEPLY DRY AIR MASS WILL BUILD
EAST ACROSS THE TN VALLEY AND APPALACHIANS THROUGH FRI NIGHT. THE
RIDGE WILL BE SHORT-LIVED HOWEVER...AS A SHARP SHORTWAVE TROUGH AND
"ALBERTA CLIPPER" LOW AMPLIFY INTO THE CENTRAL PLAINS/MID MS VALLEY
REGION...THEN LIFT/TURN NORTHEASTWARD THROUGH THE GREAT LAKES SAT-
SAT NIGHT. AN ASSOCIATED TRAILING POLAR FRONT WILL MOVE EAST ACROSS
CENTRAL NC SAT NIGHT-EARLY SUNDAY. AT THE SAME TIME...THE MODELS TO
VARYING DEGREES INDICATE AN ACTIVE SOUTHERN STREAM JET WILL SUPPORT
A WAVE OR WAVES OF LOW PRESSURE ALONG A DEVELOPING/SHARPENING
COASTAL FRONT ALONG THE SOUTHEAST US COAST...RAISING THE STAKES FOR
SOME INTERACTION OF THE TWO AS THE POLAR FRONT COLLAPSES EAST AND
INTERCEPTS DEEPENING MOISTURE CENTERED ALONG THE COASTAL CAROLINAS.
WHILE THE GFS REMAINS DRY...WITH MORE LIMITED DEEP MOISTURE OVER
CENTRAL NC...THE CONSENSUS OF OTHER GUIDANCE INCLUDING THE LATEST
EC/NMM/SREF/GEM...ALL SUPPORT VERY LIGHT QPF OVER THE EASTERN
PIEDMONT/SANDHILLS/COASTAL PLAIN SAT NIGHT...AT WHICH TIME A SLIGHT
CHANCE OF SHOWERS HAVE ACCORDINGLY BEEN INTRODUCED GENERALLY EAST OF
US HIGHWAY 1.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM THURSDAY...
THE 00Z/19TH ECMWF IS AN AGGRESSIVE OUTLIER THAT HOLDS THE
ASSOCIATED MERGED FRONTAL ZONE JUST OFFSHORE THROUGH SUN
NIGHT...WITH AN AXIS OF A QUARTER TO HALF INCH OF QPF LINGERING AS
FAR WEST AS THE I-95 CORRIDOR DURING THAT TIME. WILL FOLLOW WPC/S
PREFERENCE TOWARD A MORE PROGRESSIVE FRONTAL DEPARTURE AND
INCREASINGLY INFLUENTIAL...AND RENEWED...CONTINENTAL POLAR RIDGING
FROM THE WEST FOR THE PERIOD SUNDAY THROUGH MID-WEEK. THE ASSOCIATED
COOLEST TEMPERATURES WILL OCCUR SUN-MON...WITH HIGHS MOSTLY IN THE
UPPER 40S TO LOW 50S...AND LOWS IN THE MID-UPPER 20S...AND WITH
MODERATION INTO THE 50S AND 30S...RESPECTIVELY...THROUGH THE END OF
THE PERIOD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 100 PM THURSDAY...
AVIATION CONDITIONS WILL BE MOSTLY ADVERSE FOR THE REST OF THE
AFTERNOON. WHILE THE HEAVIEST AND MOST WIDESPREAD RAIN (AND ISOLATED
STORMS) HAS MOVED EAST OF THE CENTRAL NC TERMINALS... THE SURFACE
COLD FRONT IS STILL ALIGNED ALONG THE MOUNTAINS OF WRN NC... AND THE
COMBINATION OF MOIST LOW LEVEL AIR AND GENERALLY LIGHT SURFACE WINDS
AHEAD OF THE FRONT WILL CONTINUE TO BRING PERIODS OF MVFR TO IFR
CIGS FOR THE NEXT FEW HOURS... ALTHOUGH PERIODS OF VFR CONDITIONS
MAY MIX IN FROM TIME TO TIME. CIGS ARE LIKELY TO REBOUND TO
PREDOMINANTLY VFR AT INT/GSO AFTER ABOUT 21Z OR 22Z... ALTHOUGH THE
THREAT OF MVFR/IFR CIGS WILL NOT SIGNIFICANTLY DIMINISH UNTIL AFTER
23Z AT RDU AND AFTER 02Z AT RWI/FAY... WITH PASSAGE OF THE COLD
FRONT. AFTER THIS TIME... WINDS WILL SHIFT AROUND TO MAINLY FROM THE
NW THEN FROM THE NORTH OVERNIGHT... AT SPEEDS UNDER 10 KTS. VFR
CONDITIONS ARE LIKELY FROM LATER TONIGHT THROUGH THE END OF THE
FORECAST PERIOD (18Z FRI) AS HIGH PRESSURE BUILDS IN.
LOOKING BEYOND 18Z FRI... HIGH PRESSURE RULES THROUGH SAT... LEADING
TO VFR CONDITIONS AND FAIRLY LIGHT WINDS. PASSAGE OF A MOSTLY DRY
COLD FRONT LATE SAT NIGHT MAY BRING BRIEF MVFR CIGS. ANOTHER COOL
HIGH PRESSURE AREA WILL THEN BUILD IN SUN THROUGH TUE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...HARTFIELD/22
SHORT TERM...26
LONG TERM...26
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS PORTLAND OR
944 AM PST THU NOV 19 2015
.SYNOPSIS...LOW PRES ON THE N OREGON COAST THIS MORNING WILL
CONTINUE TO MOVE SE TODAY...INTO EASTERN OREGON THIS AFTERNOON. FLOW
WILL TURN OFFSHORE FRIDAY INTO THE UPCOMING WEEKEND AS COOL HIGH
PRESSURE SETTLES INTO THE INTERIOR PAC NW. THIS WILL LEAD TO A
PERIOD OF DRY BUT COOL WEATHER OVER THE WEEKEND. A COLD FRONT FROM
THE GULF OF ALASKA IS EXPECTED TO BRING THE NEXT CHANCE OF RAIN AND
MOUNTAIN SNOW MONDAY...WITH SHARPLY COLDER WEATHER SETTLING IN FOR
MUCH OF NEXT WEEK.
&&
.SHORT TERM...SURFACE ANALYSIS SHOWED A LOW PRES CENTER AROUND 1015
MB THIS MORNING NEARING THE COAST AROUND KTMK...PRETTY WELL ON TRACK
WITH PREVIOUS MODEL EXPECTATIONS. THE LOW IS EXPECTED TO CONTINUE TO
SLIDE OFF TO THE ESE TODAY...MOVING INTO EASTERN OREGON THIS
AFTERNOON. WITH AN OFFSHORE FLOW THROUGH THE GORGE TO THE N OF THE
EXPECTED LOW TRACK SNOW LEVELS HAD DIPPED DOWN AS LOW 1500 FT AROUND
PARKDALE....SO WILL NEED TO MENTION SOME LIGHT SNOW IN THE UPPER
GOOD RIVER VALLEY THIS MORNING UNTIL FLOW TURNS BACK ONSHORE ONCE
THE LOW MOVES E OF THE CASCADES. SNOW IN THE CASCADES THUS FAR HAS
GENERALLY BEEN ON THE LOW END OF ADVISORY...AND WITH TEMPS ON MT
HOOD NOW UP TO FREEZING AT TIMEBERLINE LODGE EXPECT MAIN SNOW
ACCUMULATION PERIOD IS OVER SO CAN DROP THE ADVISORY A LITTLE EARLY
FOR THE N OREGON CASCADES. IN THE S WA CASCADES RADAR SHOWED
PRECIPITATION BECOMING MORE SHOWERY WITH PRECIPITATION RATES IN THE
PAST FEW HOURS ONLY ON TRACK TO GIVE A COUPLE MORE INCHES OF SNOW TO
THE HIGHER TERRAIN. RADAR SUGGESTS THE BACK EDGE OF MAIN
PRECIPITATION AREA OVER OREGON ALSO PROGRESSING QUICKLY E INTO THE
CASCADES THIS MORNING. HRRR CONTINUES TO SHOW THIS WELL...WITH
LITTLE IN THE WAY OF SHOWERS FOLLOWING ON THE BACK SIDE OF THE LOW
AS LOW LEVEL FLOW BEHIND THE COLD FRONT TURNS MORE NORTHERLY.
REMAINDER OF SHORT TERM DISCUSSION UNCHANGED...BY FRI MORNING OUR
CWA SHOULD BE UNDER THE INFLUENCE OF DRY NORTHERLY FLOW...WITH A
CHILLY START TO THE DAY AND POSSIBLY PATCHY VALLEY FOG.
COLD POOL HIGH PRESSURE IS EXPECTED TO STRENGTHEN EAST OF THE
CASCADES FRIDAY AND INTO THIS WEEKEND...YIELDING BRISK EAST WINDS
THROUGH THE GORGE. FUTURE SHIFTS MAY NEED TO LOOK AT INCREASING THE
EAST WINDS INTO THE PDX METRO AREA THIS WEEKEND AS LATEST NAM RUNS
HAVE BEEN SHOWING KTTD-KDLS GRADIENTS OF -5 TO -7 MB...WHICH COULD
PRODUCE GUSTS 50-70 MPH AT THE WINDIER LOCATIONS OF THE WEST GORGE
AND 30-40 MPH NEAR TROUTDALE. THIS SEEMS FAIRLY REASONABLE GIVEN THE
COLD POOL SETUP EXPECTED TO TAKE PLACE EAST OF THE CASCADES THE NEXT
FEW DAYS. THE OFFSHORE FLOW WILL BRING A BREAK IN PRECIPITATION...
WITH A DECENT AMOUNT OF SUNSHINE OUTSIDE OF PATCHY VALLEY FOG AWAY
FROM THE GORGE. WEAGLE
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS. SATURDAY NIGHT
THROUGH WEDNESDAY...MODELS CONTINUE TO ADVERTISE A PRETTY MAJOR
PATTERN CHANGE IN THE LATTER PART OF THE EXTENDED PERIOD. SAT NIGHT
AND SUN LOOK TO REMAIN DRY WITH SOME DEGREE OF OFFSHORE LOW-LEVEL
FLOW. THERMALLY-INDUCED SURFACE TROUGH RESIDES ALONG THE COAST SAT
NIGHT THEN WEAKENS SUN. SHOULD SEE A FAIRLY LARGE MIN TEMP RANGE SAT
NIGHT WITH SUBSIDENCE INVERSIONS IN THE HIGHER TERRAIN. THINGS START
TO GET INTERESTING MON AS AN UPPER TROUGH DIVES SOUTH FROM THE GULF
OF ALASKA. THE OPERATIONAL ECMWF AND GFS ARE SIMILAR IN THE OVERALL
LARGE-SCALE PATTERN. COLD FRONTAL BOUNDARY SLIDES SOUTH THROUGH
WASHINGTON MON WITH 1000-500 MB THICKNESS VALUES LOWERING TO NEAR
530 DM ACROSS SW WA AND FAR NW OREGON 00Z TUE. BOTH MODELS THEN SHOW
A RE-ENFORCING SHOT OF COLDER AIR DIGGING INTO THE UPPER TROUGH MON
NIGHT AND TUE. BY 00Z WED THE OPERATIONAL ECMWF HAS THICKNESS VALUES
IN THE LOW TO MID 520S AND 850 MB TEMPS AROUND -6C OVER SW WA AND
FAR NW OREGON. SHOULD THIS VERIFY...SNOW LEVELS WOULD BE DOWN TO AT
LEAST 1000 FT...IF NOT A LITTLE LOWER. THE COLD PATTERN HOLDS
THROUGH WED. THE ECMWF IS MUCH SLOWER PUSHING THE UPPER TROUGH SOUTH
COMPARED TO THE GFS. IN FACT...THE GFS SHOWS NELY FLOW ALOFT WED
WITH COLD AIR STACKING UP AGAINST THE S WA AND N OREGON CASCADES.
GFS HAS 850 MB TEMPS OF -10C TO -12C OVER THE S WA AND N OREGON
CASCADE CREST 18Z WED. STILL TOO EARLY TO TRY AND PIN DOWN THE FINER
DETAILS...BUT CONFIDENCE IS GROWING THAT WE MAY ENDURE A MUCH COLDER
AIR MASS THE FIRST PART OF NEXT WEEK. WEISHAAR.
&&
.AVIATION...DEPARTING WARM FRONT WILL KEEP MIXED FLIGHT CONDITIONS
TODAY AND TONIGHT. SHOWERS IMPACTING LOCATIONS EAST OF I-5...WILL
GRADUALLY TAPER OFF THIS AFTERNOON. CIGS REMAIN MOSTLY MVFR AND
IFR...WITH VIS SLIGHTLY IMPROVING TO HIGH-END MVFR/LOW-END VFR FOR
MOST SITES AFTER 21Z THU THEN DETERIORATING AGAIN THIS EVENING.
EXPECT IFR/LIFR FOG TO DEVELOP AFTER 04Z-06Z FRI.
KPDX AND APPROACHES...MVFR CIGS/VSBYS CONTINUE TODAY AND
TONIGHT...WITH RAIN TAPERING OFF NEXT FEW HOURS. SOME IMPROVEMENT
IN CIGS LIKELY AFTER 20Z THU. EAST WINDS REMAIN REMAIN 10 TO 20 KT
EARLY THIS MORNING...DECREASING BY AROUND MIDDAY. MVFR/IFR FOG OR
LOW STRATUS DEVELOPS AFTER 06Z-08Z FRI. /27
&&
.MARINE...SURFACE LOW PRESSURE CONTINUES TO APPROACH THE
COAST...PRESENTLY ENTERING THE COASTAL WATERS /OR 60 NM
OFFSHORE/ WEST OF CASCADE HEAD. SOLID SMALL CRAFT WINDS CONTINUE
OVER ALL WATERS...WITH EAST WINDS OVER THE NORTHERN WATERS NORTH
OF THE LOW AND SOUTH TO SOUTHEAST WINDS TO THE SOUTH. AS
EXPECTED...THE STRONGEST GUSTS HAVE BEEN TO THE SOUTH AND
IMMEDIATELY AHEAD OF THE LOW.
WINDS TURN MORE NORTHERLY ONCE THE LOW MOVES ONSHORE EARLY
THURSDAY...WITH ADVISORY LEVEL GUSTS CONTINUING INTO THIS EVENING.
THEN...OVERALL WEAKLY DEFINED SURFACE PATTERN FOR MORE BENIGN
CONDITIONS. A THERMAL LOW BUILDS UP THE COAST FRIDAY AND MAY
REMAIN ALONG THE COAST THROUGH THE WEEKEND FOR OFFSHORE FLOW.
SEAS SOUTH OF CASCADE HEAD WILL REMAIN 10 TO 11 FT THROUGH LATE THIS
MORNING AS THE LOW MOVES ACROSS...BUT WILL CONTINUE TO SUBSIDE
THIS AFTERNOON. SEAS OVER THE NORTHERN WATERS REMAIN 7 TO 9 FT
RANGE THROUGH FRIDAY. SEAS SOUTH WILL SUBSIDE TO LESS THAN 10 FT
BY THURSDAY EVENING. CULLEN/27
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 7 PM PST THIS EVENING FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 PM PST THIS
AFTERNOON FOR COASTAL WATERS FROM CASCADE HEAD OR TO
FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL NOON
PST TODAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
438 PM EST THU NOV 19 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE WEST TONIGHT
THROUGH THE EARLY PART OF THE WEEKEND. A VIGOROUS COLD FRONT WILL
CROSS THE AREA FROM THE WEST SATURDAY NIGHT INTO SUNDAY...USHERING
IN THE COOLEST AIR OF THE SEASON SO FAR. DRY HIGH PRESSURE WILL THEN
RETURN FROM THE WEST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
430 PM UPDATE...TOUCHED UP T/TD TRENDS INTO THE EVENING...CORRECTING
VALUES FOR FRONTAL TIMING SOMEWHAT. MIXING IN THE WAKE OF THE
FRONT HAS BROUGHT DEWPTS DOWN HARD IN A FEW SPOTS AS WELL. I ALSO
REMOVED THE MENTION OF SHOWERS IMMEDIATELY AHEAD OF THE FRONT /EAST
OF CHARLOTTE/ THAT REMAINED LATE IN THE AFTN...SATELLITE JUST NOT
SUGGESTING CLOUDS ARE DEEP ENOUGH FOR SHOWERS. OTHERWISE THE FCST
IS ON TRACK.
AS OF 220 PM EST...A SURFACE COLD FRONT HAS REACHED THE INTERSTATE
77 CORRIDOR THIS AFTERNOON AND CONTINUES TO MAKE STEADY EASTWARD
PROGRESS. THIS HAS BEEN ACCOMPANIED BY GENERAL CLEARING...BUT
THE THE HIGHER LEVEL CIRRUS REMAINS PESKY ACROSS THE PIEDMONT AS
AN UPPER JETLET MOVING ACROSS THE APPALACHIANS SHARPENS UP UPPER
LEVEL DIVERGENCE OVER THE PIEDMONT. THIS WEAK UPPER SUPPORT WILL BE
COINCIDENT WITH A PASSING 500 MB SHORTWAVE LATE TODAY. PROFILES ARE
BECOMING INCREASINGLY DRY WITH THE FROPA...AND THE MESOSCALE MODELS
GENERALLY KEEP ANY RESULTANT SHOWERS JUST EAST OF THE FORECAST AREA.
THE LATEST HRRR DOES PRODUCE SOME ISOLD SHOWER ACTIVITY ALONG/EAST
OF THE INTERSTATE 77 CORRIDOR LATE DAY BUT SLIGHT CHANCES WILL BE
CONFINED MAINLY TO UNION COUNTY NC.
OTHERWISE...NW DOWNSLOPING FLOW ALONG WITH 850 MB COLD ADVECTION
WILL PICK UP TONIGHT AS SURFACE HIGH PRESSURE BUILDS IN FROM
THE WEST. SOME SHALLOW MOISTURE MAY LINGER ALONG THE SPINE OF
THE SRN APPALACHIANS BUT WITH LITTLE MORE THAN CLOUDS EXPECTED
IN NW UPSLOPE FLOW AREAS. THE PRES GRADIENT WILL BE RELATIVELY
TIGHT TONIGHT AS THE SURFACE HIGH BUILDS FROM THE MID MS VALLEY
TO THE CENTRAL APPALACHIANS...WHICH SHOULD KEEP MOST FOG PROBLEMS
AT BAY DESPITE THE MOIST GROUND. ANOTHER WEAK SHORTWAVE WILL PASS
OVERNIGHT IN THE INCREASINGLY ZONAL FLOW ALOFT...BUT WITH LITTLE
TO NO DEEP MOISTURE LEFT.
SOME BROAD CYCLONIC CURVATURE WILL DEVELOP IN THE FLOW ON FRIDAY
AS HEIGHTS FALL FROM THE ROCKIES INTO THE PLAINS. DOWNSLOPING
WILL CONTINUE AT LOW LEVELS...BUT 850 MB TEMPS SHOULD BE ABOUT 5
DEGREES C COOLER BY FRI AFTN COMPARED TO TODAY...WITH MAXES ABOUT
10 DEGREES LESS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM THURSDAY...MODEL GUIDANCE IN AGREEMENT ON A SERIES OF
SHORTWAVES CARVING OUT A LARGE UPPER TROF ACRS THE GREAT LAKES TO
THE GULF STATES OVER THE WEEKEND. THIS WILL PUT OUR AREA UNDER DEEP
LAYER INCREASING SOUTHWESTERLY FLOW AHEAD OF THE TROF AXIS. AT THE
SFC...A CLIPPER SYSTEM WILL DIP INTO THE MIDWEST...THEN LIFT INTO
THE GREAT LAKES. THE SYSTEM WILL DRAG A COLD FRONT ACRS THE OHIO
VALLEY ON SATURDAY...THEN ACRS THE CWFA SATURDAY NIGHT INTO SUNDAY
MORNING. THERE SHUD BE A BRIEF WINDOW WHERE MOISTURE WILL BE DEEP
ENUF WITH THE LLVL FORCING TO SQUEEZE OUT A FEW SHWRS ALONG THE TN
LINE SATURDAY NIGHT. THE ISSUE IS HOW COLD WILL THE PBL BE FOR SNOW.
IT STILL LOOK LIKE THE HIGHEST ELEVATIONS SHUD SEE A CHANGEOVER/MIX
BEFORE THE PRECIP ENDS AROUND DAYBREAK SUNDAY. ONLY VERY MINOR
ACCUMS ARE EXPECTED...IF ANY. EAST OF THE MTNS...THERE IS MORE
DISAGREEMENT AMONG THE GUIDANCE...AS A WEAK LOW PRES WAVE DEVELOPS
ALONG A STALLED FRONT OFF THE SOUTH ATLANTIC COAST. THE NAM IS AN
OUTLIER IN BRINGING A ROUND OF DEEP MOISTURE AND STOUT QPF RESPONSE
ACRS GA/SC. MEANWHILE...THE GFS HAS BEEN CONSISTENT ON KEEPING THE
PIEDMONT DRY. THE LAST TWO RUNS OF THE ECMWF HAVE SOME LIGHT QPF
MAINLY FROM I-85 AND SOUTH. THE WPC PREFERS THE ECWMF DEPICTION...SO
I HAVE ADDED A SLGT CHC TO LOW-END CHC POP ACRS THE PIEDMONT
SATURDAY NIGHT. I ALSO BUMPED MIN TEMPS UP...AS STRONG WAA AND
CLOUDS SHUD LIMIT COOLING.
ON SUNDAY...THE FRONT SHUD CLEAR THE AREA...ALLOWING LLVL FLOW TO
TURN OUT OF THE NW AND BRING STRONG CAA THRU THE AFTN. SKIES SHUD
CLEAR OUT...AND TEMPS WILL BE WELL BELOW NORMAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 125 PM THURSDAY...WE APPRECIATE WHAT LOOKS TO BE A QUIET AND
DRY PERIOD IN THE RUN UP TO THANKSGIVING. THE AXIS OF AN UPPER TROF
SHOULD SWING EASTWARD ACROSS THE FCST AREA SUNDAY NIGHT WITH LITTLE
FANFARE. IN ITS WAKE...A FLAT UPPER RIDGE WILL BUILD IN AND CARRY
SURFACE HIGH PRESSURE ACROSS THE REGION MONDAY NIGHT AND TUESDAY. IF
THERE IS A MINOR PROBLEM...IT MIGHT BE LOW TEMPS SUNDAY NIGHT/EARLY
MONDAY MORNING. MODEL GUIDANCE SHOWS SUB-FREEZING TEMPS BY SUNRISE
MONDAY...SO IF ALL GOES ACCORDING TO PLAN...THAT WILL TAKE CARE OF
OUR REMAINING FCST ZONES WHERE A FREEZE HAS NOT YET OCCURRED THIS
AUTUMN. THE UPPER RIDGE WILL START TO AMPLIFY OVER THE EAST DURING
MIDWEEK AND THAT WILL BUILD THE SURFACE HIGH AND RELOCATE IT TO OUR
NE FOR WEDNESDAY AND THURSDAY. EXPECT A SLOW WARMING TREND FOR THE
EARLY PART OF THE WEEK...THEN A SMALL JUMP UPWARD IN TEMPS FOR
MIDWEEK... BUT STILL BELOW NORMAL.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
AT KCLT...MVFR LEVEL CLOUDS CONTINUE TO SLOWLY LIFT AND SCATTER THIS
AFTN AS DRIER AIR WORKS IN FROM THE WEST...BUT UPPER LEVEL CLOUDS
WILL BE SLOWER TO CLEAR GIVEN THE SHARPENING UPPER JETLET OVER THE
APPALACHIANS. A FEW MESOSCALE MODELS PRODUCE LATE AFTERNOON SHOWERS
JUST EAST OF KCLT...BUT THIS APPEARS GENERALLY OVERDONE WITH MOST OF
THE FORCING AND LINGERING INSTABILITY EAST OF THE AREA. LIGHT WSW
WINDS SHOULD QUICKLY TOGGLE NW THIS AFTERNOON AND VEER TOWARD NRLY
OVERNIGHT. ALTHOUGH THE GROUND REMAINS MOIST AND SHALLOW FOG MAY
BECOME A CONCERN...NRLY MIXING OVERNIGHT SHOULD LARGELY PRECLUDE
RESTRICTIONS.
ELSEWHERE...LITTLE MORE THAN FEW TO SCT HIGH CLOUDS ARE EXPECTED
ACROSS THE TERMINAL FORECAST AREA GOING FORWARD. WINDS WILL CONTINUE
TO VEER NW THEN NRLY TONIGHT AS HIGH PRESSURE APPROACHES FROM THE
WEST. OCCASIONAL LOW END GUSTS ARE EXPECTED AT KAVL AS COLD
ADVECTION INCREASES BEHIND THE DEPARTING FRONT. PATCHY FOG WILL BE
POSSIBLE IN SHELTERED AREAS GIVEN THE MOIST GROUND...BUT MIXING ON
NRLY FLOW SHOULD LARGELY PRECLUDE RESTRICTIONS.
OUTLOOK...DRY HIGH PRESSURE WILL KEEP CONDITIONS VFR THROUGH SAT. A
SECONDARY COLD FRONT COULD BRING SCATTERED SHOWERS MAINLY TO THE
MOUNTAINS SAT NIGHT INTO EARLY SUNDAY...WITH SOME HIGH ELEVATION
SNOW POSSIBLE ALONG THE HIGHEST PEAKS...BUT WITH SMALL CHANCES OF
ANY RESTRICTIONS DOWN AT KAVL. DRY HIGH PRES WILL RETURN THROUGH
EARLY NEXT WEEK.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-18Z
KCLT HIGH 96% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...HG/WIMBERLEY
SHORT TERM...ARK
LONG TERM...ARK
AVIATION...HG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
224 PM EST THU NOV 19 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE WEST TONIGHT
THROUGH THE EARLY PART OF THE WEEKEND. A VIGOROUS COLD FRONT WILL
CROSS THE AREA FROM THE WEST SATURDAY NIGHT INTO SUNDAY...USHERING
IN THE COOLEST AIR OF THE SEASON SO FAR. DRY HIGH PRESSURE WILL THEN
RETURN FROM THE WEST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 220 PM EST...A SURFACE COLD FRONT HAS REACHED THE INTERSTATE
77 CORRIDOR THIS AFTERNOON AND CONTINUES TO MAKE STEADY EASTWARD
PROGRESS. THIS HAS BEEN ACCOMPANIED BY GENERAL CLEARING...BUT THE
THE HIGHER LEVEL CIRRUS REMAINS PESKY ACROSS THE PIEDMONT AS AN
UPPER JETLET MOVING ACROSS THE APPALACHIANS SHARPENS UP UPPER LEVEL
DIVERGENCE OVER THE PIEDMONT. THIS WEAK UPPER SUPPORT WILL BE
COINCIDENT WITH A PASSING 500 MB SHORTWAVE LATE TODAY. PROFILES ARE
BECOMING INCREASINGLY DRY WITH THE FROPA...AND THE MESOSCALE MODELS
GENERALLY KEEP ANY RESULTANT SHOWERS JUST EAST OF THE FORECAST AREA.
THE LATEST HRRR DOES PRODUCE SOME ISOLD SHOWER ACTIVITY ALONG/EAST
OF THE INTERSTATE 77 CORRIDOR LATE DAY BUT SLIGHT CHANCES WILL BE
CONFINED MAINLY TO UNION COUNTY NC.
OTHERWISE...NW DOWNSLOPING FLOW ALONG WITH 850 MB COLD ADVECTION
WILL PICK UP TONIGHT AS SURFACE HIGH PRESSURE BUILDS IN FROM THE
WEST. SOME SHALLOW MOISTURE MAY LINGER ALONG THE SPINE OF THE SRN
APPALACHIANS BUT WITH LITTLE MORE THAN CLOUDS EXPECTED IN NW UPSLOPE
FLOW AREAS. THE PRES GRADIENT WILL BE RELATIVELY TIGHT TONIGHT AS
THE SURFACE HIGH BUILDS FROM THE MID MS VALLEY TO THE CENTRAL
APPALACHIANS...WHICH SHOULD KEEP MOST FOG PROBLEMS AT BAY DESPITE
THE MOIST GROUND. ANOTHER WEAK SHORTWAVE WILL PASS OVERNIGHT IN THE
INCREASINGLY ZONAL FLOW ALOFT...BUT WITH LITTLE TO NO DEEP MOISTURE
LEFT.
SOME BROAD CYCLONIC CURVATURE WILL DEVELOP IN THE FLOW ON FRIDAY AS
HEIGHTS FALL FROM THE ROCKIES INTO THE PLAINS. DOWNSLOPING WILL
CONTINUE AT LOW LEVELS...BUT 850 MB TEMPS SHOULD BE ABOUT 5 DEGREES
C COOLER BY FRI AFTN COMPARED TO TODAY...WITH MAXES ABOUT 10 DEGREES
LESS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM THURSDAY...MODEL GUIDANCE IN AGREEMENT ON A SERIES OF
SHORTWAVES CARVING OUT A LARGE UPPER TROF ACRS THE GREAT LAKES TO
THE GULF STATES OVER THE WEEKEND. THIS WILL PUT OUR AREA UNDER DEEP
LAYER INCREASING SOUTHWESTERLY FLOW AHEAD OF THE TROF AXIS. AT THE
SFC...A CLIPPER SYSTEM WILL DIP INTO THE MIDWEST...THEN LIFT INTO
THE GREAT LAKES. THE SYSTEM WILL DRAG A COLD FRONT ACRS THE OHIO
VALLEY ON SATURDAY...THEN ACRS THE CWFA SATURDAY NIGHT INTO SUNDAY
MORNING. THERE SHUD BE A BRIEF WINDOW WHERE MOISTURE WILL BE DEEP
ENUF WITH THE LLVL FORCING TO SQUEEZE OUT A FEW SHWRS ALONG THE TN
LINE SATURDAY NIGHT. THE ISSUE IS HOW COLD WILL THE PBL BE FOR SNOW.
IT STILL LOOK LIKE THE HIGHEST ELEVATIONS SHUD SEE A CHANGEOVER/MIX
BEFORE THE PRECIP ENDS AROUND DAYBREAK SUNDAY. ONLY VERY MINOR
ACCUMS ARE EXPECTED...IF ANY. EAST OF THE MTNS...THERE IS MORE
DISAGREEMENT AMONG THE GUIDANCE...AS A WEAK LOW PRES WAVE DEVELOPS
ALONG A STALLED FRONT OFF THE SOUTH ATLANTIC COAST. THE NAM IS AN
OUTLIER IN BRINGING A ROUND OF DEEP MOISTURE AND STOUT QPF RESPONSE
ACRS GA/SC. MEANWHILE...THE GFS HAS BEEN CONSISTENT ON KEEPING THE
PIEDMONT DRY. THE LAST TWO RUNS OF THE ECMWF HAVE SOME LIGHT QPF
MAINLY FROM I-85 AND SOUTH. THE WPC PREFERS THE ECWMF DEPICTION...SO
I HAVE ADDED A SLGT CHC TO LOW-END CHC POP ACRS THE PIEDMONT
SATURDAY NIGHT. I ALSO BUMPED MIN TEMPS UP...AS STRONG WAA AND
CLOUDS SHUD LIMIT COOLING.
ON SUNDAY...THE FRONT SHUD CLEAR THE AREA...ALLOWING LLVL FLOW TO
TURN OUT OF THE NW AND BRING STRONG CAA THRU THE AFTN. SKIES SHUD
CLEAR OUT...AND TEMPS WILL BE WELL BELOW NORMAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 125 PM THURSDAY...WE APPRECIATE WHAT LOOKS TO BE A QUIET AND
DRY PERIOD IN THE RUN UP TO THANKSGIVING. THE AXIS OF AN UPPER TROF
SHOULD SWING EASTWARD ACROSS THE FCST AREA SUNDAY NIGHT WITH LITTLE
FANFARE. IN ITS WAKE...A FLAT UPPER RIDGE WILL BUILD IN AND CARRY
SURFACE HIGH PRESSURE ACROSS THE REGION MONDAY NIGHT AND TUESDAY. IF
THERE IS A MINOR PROBLEM...IT MIGHT BE LOW TEMPS SUNDAY NIGHT/EARLY
MONDAY MORNING. MODEL GUIDANCE SHOWS SUB-FREEZING TEMPS BY SUNRISE
MONDAY...SO IF ALL GOES ACCORDING TO PLAN...THAT WILL TAKE CARE OF
OUR REMAINING FCST ZONES WHERE A FREEZE HAS NOT YET OCCURRED THIS
AUTUMN. THE UPPER RIDGE WILL START TO AMPLIFY OVER THE EAST DURING
MIDWEEK AND THAT WILL BUILD THE SURFACE HIGH AND RELOCATE IT TO OUR
NE FOR WEDNESDAY AND THURSDAY. EXPECT A SLOW WARMING TREND FOR THE
EARLY PART OF THE WEEK...THEN A SMALL JUMP UPWARD IN TEMPS FOR
MIDWEEK... BUT STILL BELOW NORMAL.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
AT KCLT...MVFR LEVEL CLOUDS CONTINUE TO SLOWLY LIFT AND SCATTER THIS
AFTN AS DRIER AIR WORKS IN FROM THE WEST...BUT UPPER LEVEL CLOUDS
WILL BE SLOWER TO CLEAR GIVEN THE SHARPENING UPPER JETLET OVER THE
APPALACHIANS. A FEW MESOSCALE MODELS PRODUCE LATE AFTERNOON SHOWERS
JUST EAST OF KCLT...BUT THIS APPEARS GENERALLY OVERDONE WITH MOST OF
THE FORCING AND LINGERING INSTABILITY EAST OF THE AREA. LIGHT WSW
WINDS SHOULD QUICKLY TOGGLE NW THIS AFTERNOON AND VEER TOWARD NRLY
OVERNIGHT. ALTHOUGH THE GROUND REMAINS MOIST AND SHALLOW FOG MAY
BECOME A CONCERN...NRLY MIXING OVERNIGHT SHOULD LARGELY PRECLUDE
RESTRICTIONS.
ELSEWHERE...LITTLE MORE THAN FEW TO SCT HIGH CLOUDS ARE EXPECTED
ACROSS THE TERMINAL FORECAST AREA GOING FORWARD. WINDS WILL CONTINUE
TO VEER NW THEN NRLY TONIGHT AS HIGH PRESSURE APPROACHES FROM THE
WEST. OCCASIONAL LOW END GUSTS ARE EXPECTED AT KAVL AS COLD
ADVECTION INCREASES BEHIND THE DEPARTING FRONT. PATCHY FOG WILL BE
POSSIBLE IN SHELTERED AREAS GIVEN THE MOIST GROUND...BUT MIXING ON
NRLY FLOW SHOULD LARGELY PRECLUDE RESTRICTIONS.
OUTLOOK...DRY HIGH PRESSURE WILL KEEP CONDITIONS VFR THROUGH SAT. A
SECONDARY COLD FRONT COULD BRING SCATTERED SHOWERS MAINLY TO THE
MOUNTAINS SAT NIGHT INTO EARLY SUNDAY...WITH SOME HIGH ELEVATION
SNOW POSSIBLE ALONG THE HIGHEST PEAKS...BUT WITH SMALL CHANCES OF
ANY RESTRICTIONS DOWN AT KAVL. DRY HIGH PRES WILL RETURN THROUGH
EARLY NEXT WEEK.
CONFIDENCE TABLE...
19-01Z 01-07Z 07-13Z 13-18Z
KCLT HIGH 83% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...HG
SHORT TERM...ARK
LONG TERM...ARK
AVIATION...HG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
126 PM EST THU NOV 19 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE WEST TONIGHT
THROUGH THE EARLY PART OF THE WEEKEND. A VIGOROUS COLD FRONT WILL
CROSS THE AREA FROM THE WEST SATURDAY NIGHT INTO SUNDAY...USHERING
IN THE COOLEST AIR OF THE SEASON SO FAR. DRY HIGH PRESSURE WILL THEN
RETURN FROM THE WEST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 110 PM EST...A SURFACE COLD FRONT IS MAKING STEADY EASTWARD
PROGRESS ACROSS THE FORECAST AREA THIS AFTERNOON. THE HIGHER LEVEL
CLOUDS...HOWEVER...HAVE BEEN SLOW TO CLEAR AS AN UPPER JETLET MOVING
ACROSS THE APPALACHIANS CONTINUES TO SHARPEN UP THE UPPER LEVEL
DIVERGENCE OVER THE PIEDMONT. THIS WEAK UPPER SUPPORT WILL BE
COINCIDENT WITH A PASSING 500 MB SHORTWAVE LATE TODAY. PROFILES ARE
BECOMING INCREASINGLY DRY WITH THE FROPA...AND THE MESOSCALE MODELS
GENERALLY KEEP ANY RESULTANT SHOWERS JUST EAST OF THE FORECAST AREA.
THE LATEST HRRR DOES PRODUCE SOME ISOLD SHOWER ACTIVITY ALONG/EAST
OF THE INTERSTATE 77 CORRIDOR LATE DAY SO SLIGHT CHANCES WILL BE
RETAINED IN FAR EASTERN PARTS.
OTHERWISE...NW DOWNSLOPING FLOW ALONG WITH 850 MB COLD ADVECTION
WILL PICK UP TONIGHT AS SURFACE HIGH PRESSURE BUILDS IN FROM THE
WEST. SOME SHALLOW MOISTURE MAY LINGER ALONG THE SPINE OF THE SRN
APPALACHIANS BUT WITH LITTLE MORE THAN CLOUDS EXPECTED IN NW UPSLOPE
FLOW AREAS. THE PRES GRADIENT WILL BE RELATIVELY TIGHT TONIGHT AS
THE SURFACE HIGH BUILDS FROM THE MID MS VALLEY TO THE CENTRAL
APPALACHIANS...WHICH SHOULD KEEP MOST FOG PROBLEMS AT BAY DESPITE
THE MOIST GROUND. ANOTHER WEAK SHORTWAVE WILL PASS OVERNIGHT IN THE
INCREASINGLY ZONAL FLOW ALOFT...BUT WITH LITTLE TO NO DEEP MOISTURE
LEFT.
SOME BROAD CYCLONIC CURVATURE WILL DEVELOP IN THE FLOW ON FRIDAY AS
HEIGHTS FALL FROM THE ROCKIES INTO THE PLAINS. DOWNSLOPING WILL
CONTINUE AT LOW LEVELS...BUT 850 MB TEMPS SHOULD BE ABOUT 5 DEGREES
C COOLER BY FRI AFTN COMPARED TO TODAY...WITH MAXES ABOUT 10 DEGREES
LESS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
AS OF 255 AM THU...GUIDANCE IN OVERALL AGREEMENT...BUT SOME
DISCREPANCIES TO DEVELOP BY THE END OF THE PERIOD. ZONAL FLOW OVER
THE AREA FRI BECOMES MORE AMPLIFIED SAT AS A SHORT WAVE MOVES ACROSS
THE NRN PLAINS INTO THE GREAT LAKES. THE WAVE MOVES INTO SRN QUEBEC
SAT NITE AS A WEAKER WAVE DROPS INTO THE MID MS VALLEY. AT THE
SFC...HIGH PRESSURE WILL BUILDS INTO THE AREA FRI AND SAT. A COLD
FRONT ASSOCIATED WITH THE AFORE MENTIONED SHORT WAVE MOVES TOWARD
THE ARE SAT AND ACROSS THE AREA SAT NITE. THERE WILL BE SOME LOW
LEVEL MOISTURE MOVING INTO THE MTNS AND W TO NW UPSLOPE FLOW WHICH
WILL LEAD TO A CHC OF SHOWERS. TEMPS DROP RAPIDLY BEHIND THE FRONT
AND COULD ALLOW THE RAIN TO CHANGE TO SNOW AT THE HIGHER ELEVATIONS.
HOWEVER...ANY PRECIP WOULD BE VERY LIGHT AND NO ACCUMS ARE EXPECTED.
ONE COMPLICATING FACTOR IS THE GUIDANCE IS DEVELOPING A LOW PRESSURE
NEAR FL ALONG THE COLD FRONT THAT CROSSED THE AREA THU. THIS LOW
MOVES UP THE ATLANTIC COAST AND BRINGS MOISTURE INTO THE AREA. THE
GUIDANCE AGREES THAT CLOUDS WILL INCREASE...BUT DIFFERS GREATLY ON
THE LOCATION AND AMOUNT OF ANY RESULTING PRECIP. THEREFORE...HAVE
GONE WITH MORE CLOUDS...BUT KEPT THE FCST DRY. NEAR NORMAL HIGHS FRI
DROP TO AROUND 5 DEGREES BELOW NORMAL SAT. LOWS A LITTLE BELOW
NORMAL FRI NITE DROP A COUPLE OF DEGREES...BUT ARE WARMER THAN THE
PREVIOUS FCST DUE TO THE INCREASED CLOUDS.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 125 PM THURSDAY...WE APPRECIATE WHAT LOOKS TO BE A QUIET AND
DRY PERIOD IN THE RUN UP TO THANKSGIVING. THE AXIS OF AN UPPER TROF
SHOULD SWING EASTWARD ACROSS THE FCST AREA SUNDAY NIGHT WITH LITTLE
FANFARE. IN ITS WAKE...A FLAT UPPER RIDGE WILL BUILD IN AND CARRY
SURFACE HIGH PRESSURE ACROSS THE REGION MONDAY NIGHT AND TUESDAY. IF
THERE IS A MINOR PROBLEM...IT MIGHT BE LOW TEMPS SUNDAY NIGHT/EARLY
MONDAY MORNING. MODEL GUIDANCE SHOWS SUB-FREEZING TEMPS BY SUNRISE
MONDAY...SO IF ALL GOES ACCORDING TO PLAN...THAT WILL TAKE CARE OF
OUR REMAINING FCST ZONES WHERE A FREEZE HAS NOT YET OCCURRED THIS
AUTUMN. THE UPPER RIDGE WILL START TO AMPLIFY OVER THE EAST DURING
MIDWEEK AND THAT WILL BUILD THE SURFACE HIGH AND RELOCATE IT TO OUR
NE FOR WEDNESDAY AND THURSDAY. EXPECT A SLOW WARMING TREND FOR THE
EARLY PART OF THE WEEK...THEN A SMALL JUMP UPWARD IN TEMPS FOR
MIDWEEK... BUT STILL BELOW NORMAL.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
AT KCLT...MVFR LEVEL CLOUDS CONTINUE TO LIFT AND SCATTER AT ISSUANCE
TIME...BUT UPPER LEVEL CLOUDS WILL BE SLOW TO CLEAR GIVEN THE
SHARPENING UPPER JETLET OVER THE APPALACHIANS. A FEW MESOSCALE
MODELS PRODUCE LATE AFTERNOON SHOWERS JUST EAST OF KCLT...BUT THIS
APPEARS GENERALLY OVERDONE WITH MOST OF THE FORCING AND LINGERING
INSTABILITY EAST OF THE VICINITY. LIGHT WSW WINDS SHOULD QUICKLY
TOGGLE NW THIS AFTERNOON AND VEER TOWARD NRLY OVERNIGHT. ALTHOUGH
THE GROUND REMAINS MOIST AND SHALLOW FOG MAY BECOME A CONCERN...NRLY
MIXING OVERNIGHT SHOULD LARGELY PRECLUDE RESTRICTIONS.
ELSEWHERE...LITTLE MORE THAN FEW TO SCT HIGH CLOUDS ARE EXPECTED
ACROSS THE TERMINAL FORECAST AREA GOING FORWARD. WINDS WILL CONTINUE
TO VEER NW THEN NRLY TONIGHT AS HIGH PRESSURE APPROACHES FROM THE
WEST. OCCASIONAL LOW END GUSTS ARE EXPECTED AT KAVL AS COLD
ADVECTION INCREASES BEHIND THE DEPARTING FRONT. PATCHY FOG WILL BE
POSSIBLE IN SHELTERED AREAS GIVEN THE MOIST GROUND...BUT MIXING ON
NRLY FLOW SHOULD LARGELY PRECLUDE RESTRICTIONS.
OUTLOOK...DRY HIGH PRESSURE WILL KEEP CONDITIONS VFR THROUGH SAT. A
SECONDARY COLD FRONT COULD BRING SCATTERED SHOWERS MAINLY TO THE
MOUNTAINS SAT NIGHT INTO EARLY SUNDAY...WITH SOME HIGH ELEVATION
SNOW POSSIBLE ALONG THE HIGHEST PEAKS...BUT WITH SMALL CHANCES OF
ANY RESTRICTIONS DOWN AT KAVL. DRY HIGH PRES WILL RETURN THROUGH
EARLY NEXT WEEK.
CONFIDENCE TABLE...
18-24Z 00-06Z 06-12Z 12-18Z
KCLT HIGH 87% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 97% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...HG
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...HG
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
327 PM CST THU NOV 19 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 325 PM CST THU NOV 19 2015
STRONG WINDS PEAKED EAST LATE THIS MORNING AND STARTED TO DROP OFF A
BIT BEFORE NOON. THE EXITING OF A WAVE TO THE NORTHEAST RESULTED IN A
DROPOFF OF LOW LEVEL WINDS AND EVEN A LITTLE WARMING AT 5K FEET...
APPARENTLY PEGGED CORRECTLY BY THE RAP AS SEEN ON BUFKIT WITH THE
WINDS...TO CUT DOWN ON THE MIXED LAYER. ADVISORY WILL BE CONTINUED
TO ORIGINAL EXPIRATION EAST BUT WILL PLAN ON CANCELING A BIT
EARLIER SOUTHWEST. WINDS WILL THEN DROP OFF QUICKLY EARLY THIS
EVENING. SKIES WILL BE GENERALLY CLEAR THROUGH THIS EVENING THOUGH
AN INCREASE IN HIGH AND SOME MID CLOUDS WILL START BEFORE MIDNIGHT
FROM THE SOUTHWEST. TEMPERATURES WILL COOL INTO THE LOWER TO
MIDDLE 20S THIS EVENING WITH THE COOLING RATE SLOWING SOUTHWEST
LATE EVENING AS CLOUDS START TO INCREASE THERE.
LOOKING AT A FAIRLY SIGNIFICANT SNOW EVENT ACROSS THE AREA ON
FRIDAY. ON THE LARGE SCALE...A SERIES OF JET STREAKS WILL AID IN
THE DEVELOPMENT AND ENHANCEMENT OF HEAVY SNOW BAND THAT IS EXPECTED
TO DEVELOP ACROSS THE AREA. AS OF 12Z...THE MAIN JET AXIS EXTENDS
FROM THE PACIFIC NW DOWN THROUGH THE CENTRAL PORTION OF THE US.
ACROSS THE UPPER MIDWEST...THERE IS A JET STREAK ACROSS SOUTHERN
MINNESOTA INTO SOUTHERN WISCONSIN WITH THE RIGHT ENTRANCE REGION
ACROSS MUCH OF THE FORECAST AREA. EXPECT THIS JET STREAK TO AID IN
THE DEVELOPMENT OF THE BAND AS THE INTENSIFYING WAVE MOVES INTO THE
AREA.
MODEL SOUNDINGS SUGGEST A FAIR AMOUNT OF DRY AIR THAT HAS TO BE
OVERCOME INITIALLY IN THE NEAR SURFACE LAYER. EXPECT ATMOSPHERE TO
SATURATE RELATIVELY QUICKLY...WITH SNOW BEGINNING TO FALL ACROSS
SOUTH CENTRAL SOUTH DAKOTA BETWEEN 9-12Z. INITIALLY SNOW SHOULD BE
FAIRLY LIGHT...BUT SHOULD INCREASE IN INTENSITY AS STRONG 700 MB
FRONTOGENTIC FORCING MOVES INTO THE AREA. WITH SNOWFALL BEGINNING
FAIRLY LIGHT...WILL LIKELY SEE SOME MELTING AS THE SURFACE LAYER IS
STILL NEAR 40 DEGREES. BY 9 AM OR SO...IT APPEARS THAT THE
ATMOSPHERE BECOMES WEAKLY UNSTABLE ABOVE THE FRONTOGENETIC BAND. IN
ADDITION...AS THE ATMOSPHERIC COLUMN COOLS...DENDRITIC LAYER
INCREASES IN DEPTH. WITH WEAK WINDS THROUGH THE ATMOSPHERE...HAVE
THE POTENTIAL OF SEEING SNOWFALL RATIOS INCREASE AS THE DENDRITIC
DEPTH INCREASES. WITH THE INSTABILTY...COULD SEE SNOWFALL RATES
INCREASE WITHIN THE MAIN BAND TO 1"+/HOUR. HAVE RAISED SNOWFALL
AMOUNTS WITHIN THE BAND...BUT HIGHER AMOUNTS ARE POSSIBLE ESPECIALLY
FROM YANKTON TO SPENCER IA AND AREAS SOUTH TOWARDS STORM LAKE.
ON THE NORTH SIDE OF THE BAND...IT IS MUCH MORE MURKY WHERE THE
NORTHERN EDGE OF THE BAND WILL SET UP. GIVEN THE UNCERTAINTY...WILL
LEAVE THE WATCH IN PLACE FOR NOW.
AS FOR TEMPERATURES...GUIDANCE IS POOR GIVEN THE AMOUNT OF WARMING
THAT IS ANTICIPATED IN THE MODELS DURING THE PRECIPITATION EVENT.
HAVE STARTED WITH PREVIOUS FORECAST...AND MADE ONLY MINOR TWEAKS TO
THE HIGHS AT THIS POINT.
WILL BE A STRUGGLE TO WARM SIGNIFICANTLY ON SATURDAY WITH SNOWPACK
LINGERING ACROSS THE SOUTH. 925 HPA TEMPS WARM TO -5 TO -7C
THROUGHOUT THE DAY...PROMOTING HIGHS IN THE 20S. SUBTLE WARM FRONT
IS EXPECTED TO MOVE THROUGH THE AREA SATURDAY NIGHT. HAVE NOT MADE
CHANGES TO THE FORECAST SATURDAY NIGHT WITH THE FORCUS ON THE SNOW
BAND.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 325 PM CST THU NOV 19 2015
THE SUNDAY START OF DRY AND WARMING WEATHER WILL CONTINUE THROUGH AT
LEAST TUESDAY WITH UPPER RIDGING. THE WARMING FOR NOW LOOKS TO BE
MODIFIED BY SOME DELAY IN LOW LEVEL WARMING...LIKELY REMAINING SNOW
COVER ESPECIALLY SOUTHEAST...AND OF COURSE THE LOWERING LATE
NOVEMBER SUN ANGLE...SO LOOK FOR DAYTIME HIGHS NOT TO GET TOO FAR
INTO THE 40S FOR NOW. WEDNESDAY STILL LOOKS RELATIVELY MILD...BUT A
SOUTHERLY FETCH OF LOW LEVEL MOISTURE MAY AGAIN COME INTO PLAY AND
BRING A CHANCE OF RAIN OR DRIZZLE EAST. THANKSGIVING DAY LOOKS LIKE
COOLER WITH SOME CHANCE OF RAIN AND SNOW...IN SLIGHTLY DIFFERENT
WAYS BOTH THE GFS AND EC SHOW THIS. THE EC SHOWS A MUCH DEEPER
SYSTEM TO THE SOUTHWEST AS THANKSGIVING GETS HERE...BUT SO DEEP IT
IS SHEARED OFF FROM COMING UP BY THE NORTHERN WAVE...SO AT THIS TIME
IT DOES NOT LOOK LIKE A MAJOR HOLIDAY SYSTEM...BUT OF COURSE THAT
CAN CHANGE WHEN LOOKING A WEEK AHEAD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1134 AM CST THU NOV 19 2015
VFR THROUGH 20/12Z. SURFACE GUSTS 25-40 KNOTS FROM THE W/NW
DECREASING FROM THE WEST 19/21Z-20/00Z. AFTER 20/12Z INCREASING
CEILINGS 1-3K AND VISIBILITIES 3-5SM/S- SOUTHWEST OF HON/FSD/SLB
LINE...WITH AREAS OF VISIBILITIES BELOW 3SM/S DEVELOPING THIS
AREA AFTER 14Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER STORM WARNING FROM 6 AM TO 9 PM CST FRIDAY FOR SDZ068>071.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR SDZ038>040-050-
052>071.
WINTER STORM WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR SDZ065>067.
WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST FRIDAY FOR SDZ050-
063-064.
MN...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ071-072-080-081-
089-090-097-098.
IA...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ001>003-012>014-
020>022-031-032.
WINTER STORM WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR IAZ001>003.
WINTER STORM WARNING FROM 9 AM FRIDAY TO MIDNIGHT CST FRIDAY
NIGHT FOR IAZ012>014-020>022-031-032.
NE...WINTER STORM WARNING FROM 6 AM TO 9 PM CST FRIDAY FOR NEZ013-014.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ013-014.
&&
$$
SHORT TERM...
LONG TERM...
AVIATION...
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1129 AM CST THU NOV 19 2015
.DISCUSSION...SEE AVIATION DISCUSSION BELOW FOR THE 18Z TAFS.
&&
.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD.
CIGS ARE EXPECTED TO DVLP TONIGHT...BUT SHOULD REMAIN ABV 3KFT.
BRIEF PATCHY LIGHT FOG IS ALSO POSSIBLE TOWARD EARLY FRI
MORNING...HOWEVER THE CLOUDS SHOULD HINDER FOG DVLPMNT AND WILL
NOT MENTION IN TAFS AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 856 AM CST THU NOV 19 2015/
DISCUSSION...QUIET WEATHER CONDITIONS WILL PERSIST TODAY AS WINDS
GRADUALLY VEER TO THE E AND SLOWLY ADVECT LOW LEVEL MOISTURE BACK
INTO S TX. HIGHS ARE EXPECTED TO BE A TAD WARMER THAN YESTERDAY`S
VALUES. OVERALL FCST LOOKS ON TRACK WITH NO MAJOR CHANGES AT THIS
TIME. WILL UPDATE ZONES TO REMOVE MENTION OF MORNING FOG.
PREV DISCUSSION... /ISSUED 538 AM CST THU NOV 19 2015/
DISCUSSION...SEE AVIATION SECTION FOR 12Z TAFS.
AVIATION...ALTHOUGH THE TEMP/DEWPOINT SPREADS ARE NEAR ZERO FOR
THE COASTAL PLAINS...FOG HAS BEEN SLOW TO FORM WITH ONLY SPOTTY
OCCURRENCES OVER THE PAST COUPLE OF HOURS. WINDS ARE 5-7 KNOTS
FROM THE NORTH WHICH MAY KEEP FOG FROM FORMING. WILL KEEP A
TEMPO GROUP FROM 12-14Z FOR VCT FOR FOG/MVFR VSBYS. THEN CLEAR
SKIES AND VFR CONDITIONS FOR MOST OF THE DAY TODAY. CLOUDS
AROUND 6 KFT OVER THE GULF WATERS EAST OF THE LOWER TEXAS COAST
SHOULD MOVE NORTHWARD LATE THIS AFTERNOON AND REACH THE SOUTHERN
PARTS OF THE COASTAL BEND/BRUSH COUNTRY. MOISTURE ADVECTION IN
THIS LAYER WILL INCREASE TONIGHT WITH BROKEN CLOUD DECK NEAR
5 KFT REACHING LRD AT 04Z AND AT CRP BY 08Z.
PREV DISCUSSION... /ISSUED 339 AM CST THU NOV 19 2015/
SHORT TERM (TODAY THROUGH FRIDAY)...LIGHT NORTHEAST WINDS AND
NEAR ZERO TEMP/DEWPOINT SPREAD WILL LEAD TO A BRIEF POTENTIAL FOR
FOG OVER THE COASTAL PLAINS EARLY THIS MORNING. FOG HAS BEEN
REPORTED AT PORT LAVACA IN THE PAST HOUR. ONLY MODEL INDICATING
A STRONG INDICATOR FOR FOG IS THE LATEST RAP MODEL. WILL HAVE TO
WATCH TRENDS TO SEE IF FOG BECOMES DENSE OVER THE NEXT COUPLE OF
HOURS.
OTHERWISE...ANOTHER BENIGN WEATHER DAY IS EXPECTED. SURFACE HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL BUILD EASTWARD INTO THE
MID MISSISSIPPI RIVER VALLEY TODAY. WINDS WILL INCREASE FROM THE
EAST-NORTHEAST LATER TODAY. HIGH TEMPERATURES WILL BE NEAR OR
SLIGHTLY WARMER THAN YESTERDAY.
LOW LEVEL FLOW WILL VEER TO EAST-SOUTHEAST LATER TONIGHT AS LOW
PRESSURE DEEPENS LEE OF THE CENTRAL ROCKIES. LOW CLOUDS ARE
EXPECTED TO RETURN ALONG THE RIO GRANDE INTO THE BRUSH COUNTRY
LATE TONIGHT. LOW LEVEL FLOW WILL BECOME SOUTHERLY FRIDAY WITH
MOISTURE STEADILY INCREASING WITH MOSTLY CLOUDY SKIES EXPECTED.
WEAK ISENTROPIC LIFT WILL LEAD TO A SLIGHT CHANCE OF LIGHT RAIN
OVER THE COASTAL WATERS INTO THE COASTAL BEND BY THE AFTERNOON.
WENT NEAR OR SLIGHTLY BELOW COOLER NAM GUIDANCE FOR HIGHS.
MARINE...EAST-NORTHEAST FLOW IS EXPECTED TO INCREASE BY THIS
AFTERNOON OVER THE OFFSHORE WATERS TO SCEC LEVELS AND REMAIN
AT THIS STRENGTH THROUGH THE NIGHT. SWELLS OF 4 TO 5 FEET WITH
PERIOD OF 8 SECONDS ALONG WITH EAST-NORTHEAST WINDS WILL KEEP
A MODERATE RISK OF RIP CURRENTS ALONG THE COAST.
LONG TERM (FRIDAY NIGHT THROUGH THANKSGIVING DAY)...CHANCES FOR
RAIN INCREASE OUT AHEAD OF A SIGNIFICANT COLD FRONT DUE TO MOVE
THROUGH SOUTH TEXAS SATURDAY MORNING. EXPECT SCATTERED
SHOWERS...WITH BETTER CHANCES OVER THE MIDDLE TEXAS COAST WHERE LOW
LEVEL MOISTURE WILL HAVE A BETTER CHANCE AT POOLING BEFORE FROPA.
HIGHS ON SATURDAY WILL OCCUR IMMEDIATELY BEFORE THE FRONT
PASSES...WITH TEMPERATURES FALLING QUICKLY BEHIND THE FRONT. WINDS
WILL ALSO PICK UP SUBSTANTIALLY BEHIND THE FRONT...WITH SMALL CRAFT
ADVISORY CONDITIONS EASILY MET FROM FROPA ALL THE WAY THROUGH EARLY
SUNDAY. CAA WILL KEEP TEMPERATURES IN THE 50S ON SUNDAY...AND
READINGS WILL DIP INTO THE 40S AWAY FROM THE COAST MONDAY MORNING AS
HIGH PRESSURE BUILDS INTO THE REGION.
HIGH PRESSURE WILL BEGIN TO SLIDE OFF TO THE EAST LATE
MONDAY...INITIATING RETURN FLOW ALONG THE COASTAL BEND. A FEATURE OF
INTEREST WILL BE MOISTURE FROM AN EASTERN PACIFIC TROPICAL
SYSTEM...AND MEDIUM RANGE MODELS DISAGREE ON HOW MUCH OF THAT WILL
GET CAUGHT UP IN SOUTHWEST FLOW ALOFT. FOR NOW WILL FOLLOW A MIDDLE
ROAD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 81 61 77 67 70 / 0 0 20 40 50
VICTORIA 78 52 74 60 65 / 0 0 10 40 50
LAREDO 83 62 78 65 66 / 0 10 10 20 50
ALICE 82 58 78 65 68 / 0 0 20 30 50
ROCKPORT 80 62 76 66 70 / 0 0 20 40 50
COTULLA 81 56 76 62 64 / 0 0 10 20 50
KINGSVILLE 82 61 78 66 70 / 0 0 20 30 50
NAVY CORPUS 79 64 76 68 71 / 0 0 20 40 50
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TE/81...AVIATION
AREA FORECAST DISCUSSION
NWS SEATTLE WA
902 AM PST THU NOV 19 2015
.SYNOPSIS...DRY NORTHWEST FLOW ALOFT WILL ALLOW SKIES TO CLEAR OVER
WESTERN WASHINGTON TODAY. AN UPPER LEVEL RIDGE AND LOW LEVEL
OFFSHORE FLOW WILL BRING MOSTLY CLEAR COOL WEATHER TONIGHT THROUGH
THE WEEKEND. A LARGE COLD UPPER LEVEL TROUGH WILL MOVE OVER THE
REGION EARLY NEXT WEEK WITH A POSSIBILITY OF SOME SNOW AT LOWER
ELEVATIONS.
&&
.SHORT TERM...LAST NIGHTS FRONTAL SYSTEM IS JUST ABOUT OUT OF W WA
AT 8 AM THIS MORNING WITH SOME LAST AREAS OF RAIN DEPARTING FROM THE
CASCADES IN EASTERN LEWIS COUNTY. CLEARING IS UNDERWAY ON THE COAST
AND OVER MUCH OF THE NORTHERN HALF OF THE W WA INTERIOR. ONE NOTABLE
EXCEPTION IS THE EASTERN STRAIT OF JUAN DE FUCA AREA FROM SEQUIM TO
PORT ANGELES...WHERE N WINDS FLOWING ACROSS THE STRAIT HAVE BEEN
BRINGING UPSLOPE SHOWERS AND CLOUDS TO THE AREA. PER THE HRRR MODEL
THE SHOWERS WILL PROBABLY CONTINUE OFF AND ON UNTIL ABOUT NOON.
MOSTLY CLEAR SKIES TONIGHT WILL ALLOW LOW TEMPERATURES TO DROP INTO
THE UPPER 20S AND 30S FRIDAY MORNING.
AN UPPER LEVEL RIDGE WILL BUILD OVER THE REGION FRIDAY AND
SATURDAY...THEN WEAKEN ON SUNDAY. AT THE SAME TIME...A SURFACE RIDGE
OVER SOUTHERN B.C. WILL MAINTAIN DRY E-NE OFFSHORE FLOW. THIS WILL
KEEP SKIES MOSTLY CLEAR OVER W WA WITH ONLY PATCHY MORNING FOG. LOW
TEMPERATURES WILL DROP INTO THE MID 20S TO MID 30S SATURDAY MORNING
AND MAINLY THE 30S ON SUNDAY MORNING. THE FREEZING TEMPERATURES AND
PATCHY FOG COULD COMBINE TO PRODUCE ISOLATED FREEZING FOG...POSSIBLY
LAYING ISOLATED ICE PATCHES ON ROAD WAYS. KAM
.LONG TERM...PREVIOUS DISCUSSION FROM THE 328 AM AFD...THE UPPER
RIDGE WILL BEGIN WEAKENING AND MOVING EAST OF THE REGION ON
SUNDAY...BUT IT SHOULD BE ANOTHER DRY DAY. A WEAK SYSTEM WILL
PROBABLY MOVE INTO THE PACIFIC NORTHWEST ON MONDAY FOR A CHANCE OF
SHOWERS. MODELS HAVE BEEN FAIRLY CONSISTENT WITH THE IDEA THAT A
DEEP UPPER LOW WILL DIG SOUTHWARD ACROSS THE REGION FROM AROUND
MONDAY NIGHT THROUGH WEDNESDAY...AS AN UPPER RIDGE AMPLIFIES
UPSTREAM ALONG 140W. THE UPPER LOW WILL LIKELY MOVE FROM VANCOUVER
ISLAND ACROSS WESTERN WASHINGTON AND THEN INTO SOUTHEAST OREGON OR
NORTHERN NEVADA...WITH A COLD SURFACE HIGH MIGRATING SOUTH THROUGH
BRITISH COLUMBIA. THE RESULT WILL BE A COLD AIR MASS PUSHING INTO
THE FORECAST AREA WITH THE POSSIBILITY OF LOW ELEVATION SNOWFALL.
MCDONNAL
&&
.AVIATION...A WEAK SYSTEM IS PASSING THROUGH NORTHERN OREGON THIS
MORNING WITH LIGHT SHOWERS CLIPPING THE SOUTHERN TIER OF THE
CWA...MAINLY LEWIS COUNTY. THESE SHOWERS WILL DIMINISH THIS
AFTERNOON AS THIS SYSTEM EXITS. THERE ARE ALSO SHOWERS AND MVFR CIGS
IN THE EASTERN STRAIT OF JUAN DE FUCA FROM NE UPSLOPE WINDS.
OTHERWISE EXPECT VFR CONDITIONS TODAY WITH NORTHERLY WINDS AT THE
SURFACE...AND W/NW FLOW ALOFT.
AN UPPER LEVEL RIDGE WILL MAINTAIN DRY AND STABLE CONDITIONS
TONIGHT. EXPECT CLEAR SKIES WITH OFFSHORE FLOW...HOWEVER MAY SEE
SHALLOW PATCHY FOG IN THE SOUTH SOUND. 33
KSEA...CLOUDS WILL SCATTER OUT TODAY WITH VFR CONDITIONS EXPECTED.
NORTH WINDS AT THE SURFACE TO 12 KT. 33
&&
.MARINE...NORTHERLY FLOW WILL PREVAIL TODAY AS A SURFACE LOW MOVES
EAST THROUGH NORTHERN OREGON. BORDERLINE SMALL CRAFT ADVISORY WINDS
ARE FORECAST OVER THE WATERS. THE FLOW WILL TURN OFFSHORE ON FRIDAY
AS HIGH PRESSURE BUILDS OVER INTERIOR BRITISH COLUMBIA AND EASTERN
WA. OFFSHORE FLOW WILL CONTINUE THROUGH EARLY NEXT WEEK. 33
&&
.HYDROLOGY...LIGHT PRECIPITATION WILL COME TO AN END OVER THE
AREA THIS MORNING. TOTAL PRECIPITATION AMOUNTS FROM THIS
SYSTEM WILL NOT BE HYDROLOGICALLY SIGNIFICANT. LITTLE IN THE WAY OF
PRECIPITATION IS FORECAST FOR THE NEXT 7 DAYS.
RIVERS ARE RECEDING EARLY THIS MORNING WITH THE EXCEPTION OF THE SLOW
MOVING CHEHALIS. THE CHEHALIS CRESTED AT CENTRALIA OVERNIGHT.
THE CREST WILL MOVE DOWNSTREAM REACHING GRAYS HARBOR EARLY
SATURDAY MORNING. FLOOD WARNINGS ON THE GREEN AND COWLITZ WILL
BE CANCELLED THIS MORNING WITH BOTH RIVERS NOW BELOW FLOOD
STAGE. FLOOD WARNINGS REMAIN ON ALL OR PART OF THE SNOHOMISH
...SNOQUALMIE...CHEHALIS...SKAGIT AND SKOKOMISH RIVERS. THE FLOOD
WARNINGS FOR THE LOWER PORTIONS OF THE SKAGIT AND SNOQUALMIE AS
WELL AS THE UPPER PORTION OF THE SNOHOMISH WILL COME TO AN END LATER
THIS MORNING. BY TONIGHT FLOOD WARNINGS WILL ONLY REMAIN ON THE
CHEHALIS AND POSSIBLY THE LOWER REACHES OF THE SNOHOMISH. FELTON
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...A FEW FLOOD WARNINGS REMAIN IN EFFECT FOR VARIOUS RIVER
FORECAST POINTS.
PZ...SMALL CRAFT ADVISORIES FOR ALL WATERS EXCEPT GRAYS HARBOR BAR.
&&
$$
WWW.WEATHER.GOV/SEATTLE
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML