Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/20/15
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1015 PM MST TUE NOV 17 2015
.UPDATE...
ISSUED AT 812 PM MST TUE NOV 17 2015
UPDATED FORECAST TO TAKE DOWN WINTER WEATHER ADVISORY FOR THE FAR
SOUTHEAST PLAINS. RADAR HAS BEEN SHOWING RAPID IMPROVEMENT AS THE
STORMS SYSTEM CONTINUES TO PULL OFF TO THE EAST. WINDS HAVE
DECREASED SUBSTANTIALLY AND REPORTS FROM OUT THAT WAY INDICATE
CONDITIONS HAVE BEEN IMPROVING. -KT
UPDATE ISSUED AT 722 PM MST TUE NOV 17 2015
FORECAST UPDATED TO TAKE DOWN THE BLIZZARD WARNING FOR THE FAR
SOUTHEAST PLAINS. WILL MAINTAIN THE WINTER WEATHER ADVISORY FOR
THE EASTERN MOST ZONES UNTIL 800 PM.
UPDATE ISSUED AT 527 PM MST TUE NOV 17 2015
UPDATED FORECAST TO EXTEND BLIZZARD WARNING UNTIL 7 PM FOR THE FAR
EASTERN PLAINS WHERE PERSISTENT SNOW BAND CONTINUES. HRRR SHOWS
THIS DECREASING SIGNIFICANTLY AFTER 7 PM...SO CURRENT THINKING IS
A DOWNGRADE TO A WINTER WEATHER ADVISORY THROUGH 8 PM TO FINISH
OFF THE EVENT. ALL OTHER HIGHLIGHTS ALLOWED TO EXPIRE. -KT
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 350 PM MST TUE NOV 17 2015
...AUTUMN BLIZZARD HAS BROUGHT MAJOR IMPACTS TO SOUTHEAST COLORADO...
AUTUMN BLIZZARD CONTINUES ACROSS PARTS OF THE AREA THIS AFTERNOON.
RIGHT NOW THE PRIMARY AREAS BEING IMPACTED WITH BLIZZARD CONDITIONS
ARE EASTERN LAS ANIMAS...BACA...PROWERS AND EASTERN KIOWA COUNTIES.
WEB CAMS INDICATE HEAVY...BLOWING SNOW AND WHITEOUT CONDITIONS IN
THESE AREAS FOR SEVERAL HOURS THIS AFTERNOON...CONTINUING AT THIS
TIME. WINDS ARE STILL GUSTING 50 TO 60 MPH...CONTRIBUTING TO A LOT
OF DRIFTING SNOW...HIGHWAY CLOSURES...POWER AND COMMUNICATION
DISRUPTIONS. BLIZZARD WARNING CONTINUES THESE AREAS THROUGH 5
PM. A WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW WILL
CONTINUE FOR THESE AREAS BETWEEN 5 AND 8 PM AS CONDITIONS BEGIN
TO IMPROVE FROM WEST TO EAST.
JUST TO THE WEST AND NORTH OF THE SNOW...STRONG AND DAMAGING WINDS
WILL CONTINUE THROUGH THE AFTERNOON...WITH GUSTS TO AROUND 60 MPH
STILL POSSIBLE. THIS INCLUDES CROWLEY...OTERO...WESTERN KIOWA AND
BENT COUNTIES. SNOW MAY COMBINE WITH THE WINDS IN THESE AREAS AT
TIMES TO PRODUCE REDUCED VISIBILITIES...ESPECIALLY ACROSS SOUTHERN
BENT AND SOUTHERN OTERO COUNTIES.
STORM IS PRETTY MUCH HISTORY FARTHER WEST. THE SOUTHERN I-25
CORRIDOR...AROUND TRINIDAD AND RATON PASS...COULD SEE A FEW MORE
EVENING SNOW SHOWERS. ALSO...THE CENTRAL MOUNTAINS COULD SEE SOME
SNOW SHOWERS TONIGHT THROUGH THE DAY TOMORROW. FOR EVERYONE
ELSE...IT SHOULD REMAIN DRY FOR THE NEXT 24 HOURS.
THIS STORM HAS BROUGHT MAJOR IMPACTS TO SOUTHEAST COLORADO...
INCLUDING POWER AND COMMUNICATION OUTAGES...HIGHWAY CLOSURES AND
TREE DAMAGE. TRAVEL IS HAZARDOUS...AND IN SOME CASES NOT
POSSIBLE...ACROSS PARTS OF LAS ANIMAS...BACA...PROWERS AND EASTERN
KIOWA COUNTIES AT THIS TIME. HIGHWAY 287...385 FROM SOUTH OF LAMAR
TO THE OKLAHOMA BORDER IS CLOSED. HIGHWAY 160 FROM EAST OF TRINIDAD
TO SPRINGFIELD IS ALSO CLOSED. IF POSSIBLE...AVOID TRAVEL AND STAY
HOME. ATTEMPTING TRAVEL IN THESE AREAS THIS EVENING WOULD BE
EXTREMELY HAZARDOUS IF NOT FUTILE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH NEXT TUESDAY)
ISSUED AT 350 PM MST TUE NOV 17 2015
MAIN LONGER TERM METEOROLOGICAL ISSUES INCLUDE TEMPERATURES...THE
POTENTIAL FOR GUSTY WINDS AT TIMES AND BASICALLY NIL TO LOW-GRADE
POPS(WITH POPS GENERALLY FAVORING PORTIONS OF THE CENTRAL
MOUNTAINS AT TIMES...ALTHOUGH A PERIOD OF LIGHT PRECIPITATION WILL
BE POSSIBLE OVER THE INTERSTATE 25 CORRIDOR AND NEARBY LOCATIONS
FROM FRIDAY INTO FRIDAY NIGHT).
RELATIVELY TRANQUIL CONDITIONS ARE ANTICIPATED OVER THE FORECAST
DISTRICT DURING THE LONGER TERM AS GENERALLY NORTHWESTERLY TO
ZONAL UPPER FLOW PREVAILS DURING THIS TIME FRAME. AT THE
SURFACE...VARYING DEGREES OF EASTERN COLORADO LEE-SIDE SURFACE
TROUGHING IN PLACE FROM THURSDAY INTO THURSDAY NIGHT IN ADVANCE
OF NEXT NORTHERLY SURFACE SURGE FRIDAY MORNING.
THE HIGHEST POTENTIAL FOR GUSTY GRADIENT WINDS DURING THE LONGER
TERM ARE ANTICIPATED FROM WEDNESDAY NIGHT INTO FRIDAY MORNING AND
THEN AGAIN FROM MONDAY NIGHT INTO NEXT TUESDAY. FINALLY...COOLEST
TEMPERATURES DURING THE LONGER TERM SHOULD BE EXPERIENCED FROM
THURSDAY INTO SATURDAY...WITH WARMER CONDITIONS DEVELOPING FROM
SUNDAY INTO NEXT TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1013 PM MST TUE NOV 17 2015
KALS...BUFKIT SOUNDING DATA IS INDICATING FOG DEVELOPING TONIGHT
AT KALS AND GIVEN THE SNOW OVER THE PAST COUPLE OF DAYS WOULD NOT
BE SURPRISED TO SEE IT DEVELOP. HAVE MVFR TO IFR CONDITIONS 10-16Z
TONIGHT. ONCE FOG DISSIPATES WEDNESDAY MORNING...EXPECT VFR
CONDITIONS DURING THE AFTERNOON AND EVENING.
KCOS AND KPUB...VFR CONDITIONS THROUGH THE NEXT 24 HOURS. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KT
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS ALBANY NY
511 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 EARLY THURSDAY FOLLOWING BY HEAVIER
SHOWERS LATER IN THE DAY AS A COLD FRONT CROSSES 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 430 PM EST...CLOUDS CONTINUED TO OVERSPREAD THE REGION. TEMEPRATURES
REMAINED MILD...50-55 IN MOST PLACES.
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 SHOULD ENCROACH ALL AREAS SHORTLY AFTER DARK. 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 /22Z WEDNESDAY THROUGH MONDAY/...
VFR CONDITIONS TO DETIORATE TO MVFR THIS EVENING AT ALL THE TAF SITES.
STRATUS CONTINUED TO ENCROACH THE ENTIRE AREA AND SHOULD DO SO
SHORTLY AFTER DARK. THESE STRATUS WILL START IN THE VFR (3500
FEET AGL) BUT SHOULD LOWER INTO THE MVFR...POSSIBLY LOW MVFR
RANGE. THERE IS A CHANCE OF IFR CIGS AFTER MIDNIGHT...ESPECIALLY
AT KPSF. FOR NOW...DID NOT INCLUDE IN THE TAFS BUT IF YOU ARE
PLANNING TO FLY OVERNIGHT OR EARLY TOMORROW YOU MIGHT WANT TO
DOUBLE CHECK THE FORECAST.
WE EXPECT SPOTTY DRIZZLE (NOT EXTENSIVE DRIZZLE) TOWARD
SUNRISE THURSDAY. THEN...SHOWERS WILL DEVELOP BY MIDDAY.
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
NEAR TERM...HWJIV
SHORT TERM...HWJIV/KL
LONG TERM...WASULA
AVIATION...HWJIV
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV/KL/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
445 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 EARLY THURSDAY FOLLOWING BY HEAVIER
SHOWERS LATER IN THE DAY AS A COLD FRONT CROSSES 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 430 PM EST...CLOUDS CONTINUED TO OVERSPREAD THE REGION. TEMEPRATURES
REMAINED MILD...50-55 IN MOST PLACES.
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 SHOULD ENCROACH ALL AREAS SHORTLY AFTER DARK. 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.
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 /20Z WEDNESDAY THROUGH MONDAY/...
VFR CONDITIONS TO DETIORATE TO MVFR THIS EVENING AT ALL THE TAF SITES.
STRATUS CONTINUED TO ENCROACH THE ENTIRE AREA AND SHOULD DO SO
SHORTLY AFTER DARK. THESE STRATUS WILL START IN THE VFR (3500
FEET AGL) BUT SHOULD LOWER INTO THE MVFR...POSSIBLY LOW MVFR
RANGE. THERE IS A CHANCE OF IFR CIGS AFTER MIDNIGHT...ESPECIALLY
AT KPSF. FOR NOW...DID NOT INCLUDE IN THE TAFS BUT IF YOU ARE
PLANNING TO FLY OVERNIGHT OR EARLY TOMORROW YOU MIGHT WANT TO
DOUBLE CHECK THE FORECAST.
WE EXPECT SPOTTY DRIZZLE (NOT EXTENSIVE DRIZZLE) TOWARD
SUNRISE THURSDAY. THEN...SHOWERS WILL DEVELOP BY MIDDAY.
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
NEAR TERM...HWJIV
SHORT TERM...HWJIV/KL
LONG TERM...WASULA
AVIATION...HWJIV
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV/KL/WASULA
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1251 PM EST WED NOV 18 2015
.SYNOPSIS...
HIGH PRESSURE WILL BRING SEASONABLY COOL AND DRY WEATHER TODAY...
THEN A PERIOD OF RAIN IS LIKELY LATE THURSDAY INTO FRIDAY AS LOW
PRESSURE MOVES ACROSS THE REGION. HIGH PRESSURE BRIEFLY RETURNS
FOR THE WEEKEND THOUGH AN UPPER LEVEL DISTURBANCE MAY BRING A
CHANCE OF PRECIP TO THE NORTHERN ZONES AT SOME POINT DURING THE
WEEKEND. DRY...COOL WEATHER RETURNS EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1245 PM UPDATE...
AREA OF LOW CLOUDS ACROSS W MA AND N CT AND EXTENDING INTO S RI IS
ERODING ON WESTERN END ACROSS W CT. HOWEVER...MORE CLOUDS ARE
ADVANCING NE FROM SE NY. A PERIOD OF PARTIAL SUNSHINE IS LIKELY IN
W MA AND WESTERN HALF CT THIS AFTERNOON BEFORE CLOUDS FILL BACK
IN. OTHERWISE...SUNSHINE WILL PREVAIL ACROSS E MA WITH LEADING
EDGE OF LOWER CLOUDS EXPECTED TO EXPAND ACROSS RI AND CENTRAL MA.
UPDATED T/TD/SKY GRIDS...OTHERWISE FORECAST ON TRACK.
PREVIOUS DISCUSSION...
LOW CLOUDS HAVE MOVED ACROSS N CT AND W MA THIS MORNING. RAP AND
NAM LOW LEVEL MOISTURE FIELDS ARE DOING A PRETTY GOOD JOB PICKING
UP ON THESE CLOUDS AND SUGGEST THE LOW CLOUDS WILL EXPAND INTO RI
AND CENTRAL MA THIS AFTERNOON AND POSSIBLY INTO SE MA BY LATE IN
THE DAY. MOST SUNSHINE THROUGH TODAY WILL BE ACROSS E MA. ADJUSTED
SKY GRIDS TO REFLECT CURRENT TRENDS AND LOWERED MAX TEMPS IN THE
WEST DUE TO CLOUD COVER. MAX TEMPS RANGE FROM MID 40S TO LOWER
50S...MILDEST TEMPS ACROSS E MA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
MID LEVEL RIDGE AXIS MOVES TO THE EAST TONIGHT...WITH MOISTURE
SLOWLY INCREASING THROUGH THE NIGHT...MAINLY ACROSS WESTERN NEW
ENGLAND. STILL LOTS OF LOW LEVEL DRY AIR TO OVERCOME. CANNOT RULE
OUT SOME SHOWERS AFTER MIDNIGHT AS THE DEEPER MOISTURE ARRIVES.
RAINFALL CHANCES CONTINUE TO INCREASE THROUGH THE DAY THURSDAY
FROM WEST TO EAST.
TEMPERATURES WILL BE TRICKY TONIGHT. STRONG SOUTHERLY WINDS AND
INCREASING CLOUDS COULD BE ENOUGH TO RESULT IN A NON-DIURNAL
TEMPERATURE TREND. EXPECTING SLIGHTLY ABOVE NORMAL MIN
TEMPERATURES. ABOVE NORMAL TEMPERATURES CONTINUE INTO THURSDAY AS
WELL.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
HIGHLIGHTS...
* RAIN LIKELY THU NIGHT INTO FRI
* SEASONABLY COOL OR BELOW NORMAL TEMPS THIS WEEKEND INTO NEXT MON
* SLIGHT CHANCE OF PRECIP SOMETIME THIS WEEKEND
THURSDAY NIGHT THROUGH FRIDAY...18/00Z MODELS ARE IN DECENT
AGREEMENT THROUGH THIS PORTION OF THE FORECAST. AN ANOMALOUSLY
STRONG UPPER LEVEL LOW OVER HUDSON BAY WILL BE THE MAIN INFLUENCE
OVER SOUTHERN NEW ENGLANDS WEATHER DURING THIS TIME PERIOD. BETWEEN
THIS UPPER LEVEL LOW/TROUGH AND AN UPPER RIDGE OVER THE WESTERN
ATLANTIC IS STRONG SOUTHWESTERLY FLOW RIGHT OVER SOUTHERN NEW
ENGLAND. THIS RESULTS IN A STRONG LOW LEVEL JET AND PWATS 2 TO 3
STD ABOVE NORMAL. THIS IS PLENTY OF MOISTURE AND ENOUGH FORCING TO
RESULT IN A PERIOD OF RAINFALL.
RAINFALL AMOUNTS ARE STILL A BIT UNCERTAIN. THE MODELS HAVE FLIP
FLOPPED FROM LAST NIGHT WITH MORE RAIN EXPECTED OUT OF THE GFS
/OVER 2 INCHES/ VERSUS ABOUT AN INCH OUT OF THE ECMWF. BASED ON THE
LAST FEW STORMS UNDER PERFORMING AND THE GFS BEING THE OUTLIER FOR
THIS STORM THE LAST FEW RUNS...HAVE OPTED TO GO WITH THE WPC QPF
WHICH APPEARS TO BE A BIT OF A BLEND. THIS KEEPS RAINFALL TOTALS IN
THE INCH TO INCH AND A HALF RANGE.
DESPITE THE STRONG LOW LEVEL JET...WARMER TEMPERATURES JUST OFF THE
SURFACE WILL KEEP THESE STRONGER WINDS FROM MIXING DOWN TO THE
SURFACE. GUSTY WINDS ARE EXPECTED BUT THESE WILL LIKELY REMAIN
BELOW ADVISORY CRITERIA.
SATURDAY THROUGH SUNDAY...MODELS DIVERGE QUITE A BIT DURING THIS
TIME FRAME. THE GFS MOVES HIGH PRESSURE OUT QUICKLY AND BRINGS A
COLD FRONT THROUGH SOUTHERN NEW ENGLAND SATURDAY AND HIGH PRESSURE
BUILDING BACK IN SUNDAY. THE ECMWF HAS HIGH PRESSURE THROUGH BOTH
DAYS IN SOUTHERN NEW ENGLAND WITH LOW PRESSURE MOVING THROUGH THE
GREAT LAKES ON SATURDAY. DESPITE THE TWO DIFFERENT SCENARIOS...BOTH
MODELS ARE PUTTING OUT SOME PRECIP...MOSTLY ACROSS NORTHERN NEW
ENGLAND BUT REACHING DOWN INTO OUR NORTHERN ZONES. HAVE A SLIGHT
CHANCE OF MOSTLY RAIN DURING THIS TIME PERIOD. A FEW SNOW FLAKES
COULD MIX IN AT THE HIGHER ELEVATIONS...DEPENDING ON THE TIMING OF
THESE FEATURES.
MONDAY AND TUESDAY...THERE IS ACTUALLY QUITE GOOD AGREEMENT AMONGST
THE MODELS FOR THIS TIME FRAME DESPITE THE DIFFERENCES EARLIER ON.
HIGH PRESSURE IN THE MIDWEST MONDAY BUILDS INTO SOUTHERN NEW ENGLAND
TUESDAY. THIS WILL BRING DRY BUT COOL WEATHER TO THE REGION.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY NIGHT/...
THROUGH 00Z...MVFR CIGS ACROSS W MA...N CT AND RI WILL EXPAND
ACROSS CENTRAL MA. CLOUDS MAY TEMPORARILY SCATTER OUT WITH A
PERIOD OF VFR IN THE CT VALLEY THIS AFTERNOON. REMAINING VFR E
MA.
TONIGHT...HIGH CONFIDENCE IN MVFR CIGS EXPANDING EAST ACROSS
EASTERN NEW ENG BUT LOWER CONFIDENCE IN TIMING. LOW PROB FOR IFR
CIGS W NEW ENG LATE. CHANCE OF SHOWERS DEVELOPING IN W NEW ENG
LATE.
THURSDAY...MODERATE CONFIDENCE. WIDESPREAD MVFR CONDITIONS AS
SHOWERS DEVELOP FROM WEST TO EAST DURING THE DAY...NOT LIKELY
REACHING SE COASTAL MA UNTIL LATE IN THE DAY. AREAS OF IFR W NEW
ENG DURING THE AFTERNOON AS HEAVIER SHOWERS DEVELOP. S/SE WIND
GUSTS TO 25 KT DEVELOPING ALONG THE S COAST.
THURSDAY NIGHT...HIGH CONFIDENCE. WIDESPREAD IFR/LIFR DEVELOPING
AS HEAVY SHOWERS MOVE ACROSS THE REGION WITH AREAS OF FOG. ISOLD
THUNDER POSSIBLE S COAST. S WIND GUSTS TO 25-30 KT IN THE COASTAL
PLAIN AND S COAST. LOCALIZED LLWS POSSIBLE AS THE LOW LEVEL JET
MOVES ACROSS THE REGION.
KBOS TAF...HIGH CONFIDENCE IN TRENDS. LOWER CONFIDENCE IN TIMING.
KBDL TAF...HIGH CONFIDENCE IN TRENDS. LOWER CONFIDENCE IN TIMING.
OUTLOOK /FRIDAY THROUGH SUNDAY/...
FRIDAY...MODERATE CONFIDENCE. MVFR/IFR CONDITIONS LIKELY EARLY IN
WIDESPREAD SHRA AND AREAS OF FOG. CONDITIONS IMPROVE FROM WEST TO
EAST DURING THE DAY.
SATURDAY AND SUNDAY...LOW CONFIDENCE. MAINLY VFR CONDITIONS BUT A
LOW PROBABILITY OF MVFR CONDITIONS IN SHRA/SHSN ACROSS NORTHERN
ZONES SOMETIME SATURDAY/SATURDAY NIGHT.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...HIGH CONFIDENCE.
QUIET BOATING WEATHER THROUGH TODAY WITH LIGHT WINDS AND RATHER
TRANQUIL SEAS. SE WINDS SLOWLY INCREASE TONIGHT INTO THURSDAY.
GUSTS UP TO 20 KT DEVELOPING OVER RI COASTAL WATERS LATE TONIGHT.
S-SE WINDS 20 TO 30 KT POSSIBLE THURSDAY AHEAD OF AN OCCLUDED
FRONT. SHOWERS OVERSPREADING THE WATERS FROM WEST TO EAST.
OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...
MODERATE CONFIDENCE. SOUTHEASTERLY WINDS AND SEAS INCREASE
THURSDAY NIGHT AS LOW PRESSURE APPROACHES THE WATERS. THEY SHIFT
TO THE WEST AND BEGIN TO DIMINISH FRIDAY AND CONTINUE THROUGH
SUNDAY AS HIGH PRESSURE BUILDS OVER THE WATERS. SMALL CRAFT
ADVISORIES WILL LIKELY BE NECESSARY FOR THE THURSDAY NIGHT AND
FRIDAY TIME PERIOD. IN ADDITION...THERE IS A LOW PROBABILITY OF
WESTERLY MARGINAL SMALL CRAFT WINDS ON SUNDAY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM TO 6 PM EST THURSDAY FOR
ANZ231>233-250-251-254-255.
SMALL CRAFT ADVISORY FROM 10 AM TO 6 PM EST THURSDAY FOR
ANZ235-237.
SMALL CRAFT ADVISORY FROM 7 AM TO 6 PM EST THURSDAY FOR ANZ256.
&&
$$
SYNOPSIS...BELK/RLG
NEAR TERM...KJC
SHORT TERM...BELK
LONG TERM...RLG
AVIATION...KJC/RLG
MARINE...BELK/RLG
AREA FORECAST DISCUSSION
NWS TAUNTON MA
955 AM EST WED NOV 18 2015
.SYNOPSIS...
HIGH PRESSURE WILL BRING SEASONABLY COOL AND DRY WEATHER TODAY...
THEN A PERIOD OF RAIN IS LIKELY LATE THURSDAY INTO FRIDAY AS LOW
PRESSURE MOVES ACROSS THE REGION. HIGH PRESSURE BRIEFLY RETURNS
FOR THE WEEKEND THOUGH AN UPPER LEVEL DISTURBANCE MAY BRING A
CHANCE OF PRECIP TO THE NORTHERN ZONES AT SOME POINT DURING THE
WEEKEND. DRY...COOL WEATHER RETURNS EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
950 AM UPDATE...
LOW CLOUDS HAVE MOVED ACROSS N CT AND W MA THIS MORNING. RAP AND
NAM LOW LEVEL MOISTURE FIELDS ARE DOING A PRETTY GOOD JOB PICKING
UP ON THESE CLOUDS AND SUGGEST THE LOW CLOUDS WILL EXPAND INTO RI
AND CENTRAL MA THIS AFTERNOON AND POSSIBLY INTO SE MA BY LATE IN
THE DAY. MOST SUNSHINE THROUGH TODAY WILL BE ACROSS E MA. ADJUSTED
SKY GRIDS TO REFLECT CURRENT TRENDS AND LOWERED MAX TEMPS IN THE
WEST DUE TO CLOUD COVER. MAX TEMPS RANGE FROM MID 40S TO LOWER
50S...MILDEST TEMPS ACROSS E MA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
MID LEVEL RIDGE AXIS MOVES TO THE EAST TONIGHT...WITH MOISTURE
SLOWLY INCREASING THROUGH THE NIGHT...MAINLY ACROSS WESTERN NEW
ENGLAND. STILL LOTS OF LOW LEVEL DRY AIR TO OVERCOME. CANNOT RULE
OUT SOME SHOWERS AFTER MIDNIGHT AS THE DEEPER MOISTURE ARRIVES.
RAINFALL CHANCES CONTINUE TO INCREASE THROUGH THE DAY THURSDAY
FROM WEST TO EAST.
TEMPERATURES WILL BE TRICKY TONIGHT. STRONG SOUTHERLY WINDS AND
INCREASING CLOUDS COULD BE ENOUGH TO RESULT IN A NON-DIURNAL
TEMPERATURE TREND. EXPECTING SLIGHTLY ABOVE NORMAL MIN
TEMPERATURES. ABOVE NORMAL TEMPERATURES CONTINUE INTO THURSDAY AS
WELL.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
HIGHLIGHTS...
* RAIN LIKELY THU NIGHT INTO FRI
* SEASONABLY COOL OR BELOW NORMAL TEMPS THIS WEEKEND INTO NEXT MON
* SLIGHT CHANCE OF PRECIP SOMETIME THIS WEEKEND
THURSDAY NIGHT THROUGH FRIDAY...18/00Z MODELS ARE IN DECENT
AGREEMENT THROUGH THIS PORTION OF THE FORECAST. AN ANOMALOUSLY
STRONG UPPER LEVEL LOW OVER HUDSON BAY WILL BE THE MAIN INFLUENCE
OVER SOUTHERN NEW ENGLANDS WEATHER DURING THIS TIME PERIOD. BETWEEN
THIS UPPER LEVEL LOW/TROUGH AND AN UPPER RIDGE OVER THE WESTERN
ATLANTIC IS STRONG SOUTHWESTERLY FLOW RIGHT OVER SOUTHERN NEW
ENGLAND. THIS RESULTS IN A STRONG LOW LEVEL JET AND PWATS 2 TO 3
STD ABOVE NORMAL. THIS IS PLENTY OF MOISTURE AND ENOUGH FORCING TO
RESULT IN A PERIOD OF RAINFALL.
RAINFALL AMOUNTS ARE STILL A BIT UNCERTAIN. THE MODELS HAVE FLIP
FLOPPED FROM LAST NIGHT WITH MORE RAIN EXPECTED OUT OF THE GFS
/OVER 2 INCHES/ VERSUS ABOUT AN INCH OUT OF THE ECMWF. BASED ON THE
LAST FEW STORMS UNDER PERFORMING AND THE GFS BEING THE OUTLIER FOR
THIS STORM THE LAST FEW RUNS...HAVE OPTED TO GO WITH THE WPC QPF
WHICH APPEARS TO BE A BIT OF A BLEND. THIS KEEPS RAINFALL TOTALS IN
THE INCH TO INCH AND A HALF RANGE.
DESPITE THE STRONG LOW LEVEL JET...WARMER TEMPERATURES JUST OFF THE
SURFACE WILL KEEP THESE STRONGER WINDS FROM MIXING DOWN TO THE
SURFACE. GUSTY WINDS ARE EXPECTED BUT THESE WILL LIKELY REMAIN
BELOW ADVISORY CRITERIA.
SATURDAY THROUGH SUNDAY...MODELS DIVERGE QUITE A BIT DURING THIS
TIME FRAME. THE GFS MOVES HIGH PRESSURE OUT QUICKLY AND BRINGS A
COLD FRONT THROUGH SOUTHERN NEW ENGLAND SATURDAY AND HIGH PRESSURE
BUILDING BACK IN SUNDAY. THE ECMWF HAS HIGH PRESSURE THROUGH BOTH
DAYS IN SOUTHERN NEW ENGLAND WITH LOW PRESSURE MOVING THROUGH THE
GREAT LAKES ON SATURDAY. DESPITE THE TWO DIFFERENT SCENARIOS...BOTH
MODELS ARE PUTTING OUT SOME PRECIP...MOSTLY ACROSS NORTHERN NEW
ENGLAND BUT REACHING DOWN INTO OUR NORTHERN ZONES. HAVE A SLIGHT
CHANCE OF MOSTLY RAIN DURING THIS TIME PERIOD. A FEW SNOW FLAKES
COULD MIX IN AT THE HIGHER ELEVATIONS...DEPENDING ON THE TIMING OF
THESE FEATURES.
MONDAY AND TUESDAY...THERE IS ACTUALLY QUITE GOOD AGREEMENT AMONGST
THE MODELS FOR THIS TIME FRAME DESPITE THE DIFFERENCES EARLIER ON.
HIGH PRESSURE IN THE MIDWEST MONDAY BUILDS INTO SOUTHERN NEW ENGLAND
TUESDAY. THIS WILL BRING DRY BUT COOL WEATHER TO THE REGION.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...
TODAY...MVFR CIGS ACROSS CT VALLEY AND W MA WILL GRADUALLY EXPAND
INTO RI AND CENTRAL MA. REMAINING VFR E MA.
TONIGHT...HIGH CONFIDENCE IN MVFR CIGS EXPANDING EAST ACROSS SNE
BUT LOWER CONFIDENCE IN TIMING. LOW PROB FOR IFR CIGS W NEW ENG
LATE. CHANCE OF SHOWERS OR PATCHY DRIZZLE W NEW ENG LATE.
THURSDAY...MODERATE CONFIDENCE. WIDELY RANGING CONDITIONS. VFR
MORE LIKELY EAST...WITH MVFR CONDITIONS...WHICH COULD DROP TO
IFR...IN WIDESPREAD SHRA FARTHER WEST. LOW PROBABILITY FOR
ISOLATED TSRA WEST LATE.
KBOS TAF...HIGH CONFIDENCE IN TAF.
KBDL TAF...HIGH CONFIDENCE IN TAF.
OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...
THURSDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE. MVFR/IFR
CONDITIONS LIKELY IN WIDESPREAD SHRA AND AREAS OF FOG. CONDITIONS
IMPROVE FROM WEST TO EAST LATE FRIDAY/FRIDAY NIGHT.
SATURDAY AND SUNDAY...LOW CONFIDENCE. MAINLY VFR CONDITIONS BUT A
LOW PROBABILITY OF MVFR CONDITIONS IN SHRA/SHSN ACROSS NORTHERN
ZONES SOMETIME SATURDAY/SATURDAY NIGHT.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...HIGH CONFIDENCE.
QUIET BOATING WEATHER THROUGH TODAY WITH LIGHT WINDS AND RATHER
TRANQUIL SEAS. SE WINDS SLOWLY INCREASE TONIGHT INTO THURSDAY.
GUSTS UP TO 20 KT DEVELOPING OVER RI COASTAL WATERS LATE TONIGHT.
S-SE WINDS 20 TO 30 KT POSSIBLE THURSDAY AHEAD OF AN OCCLUDED
FRONT. SHOWERS OVERSPREADING THE WATERS FROM WEST TO EAST.
OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...
MODERATE CONFIDENCE. SOUTHEASTERLY WINDS AND SEAS INCREASE
THURSDAY NIGHT AS LOW PRESSURE APPROACHES THE WATERS. THEY SHIFT
TO THE WEST AND BEGIN TO DIMINISH FRIDAY AND CONTINUE THROUGH
SUNDAY AS HIGH PRESSURE BUILDS OVER THE WATERS. SMALL CRAFT
ADVISORIES WILL LIKELY BE NECESSARY FOR THE THURSDAY NIGHT AND
FRIDAY TIME PERIOD. IN ADDITION...THERE IS A LOW PROBABILITY OF
WESTERLY MARGINAL SMALL CRAFT WINDS ON SUNDAY.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM TO 6 PM EST THURSDAY FOR
ANZ231>233-250-251-254-255.
SMALL CRAFT ADVISORY FROM 10 AM TO 6 PM EST THURSDAY FOR
ANZ235-237.
SMALL CRAFT ADVISORY FROM 7 AM TO 6 PM EST THURSDAY FOR ANZ256.
&&
$$
SYNOPSIS...BELK/RLG
NEAR TERM...KJC
SHORT TERM...BELK
LONG TERM...RLG
AVIATION...BELK/KJC/RLG
MARINE...BELK/RLG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
ISSUED BY NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
432 PM EST WED NOV 18 2015
.SYNOPSIS...
HIGH PRESSURE OVER NEW ENGLAND WILL MOVE EAST OF THE REGION
TONIGHT AHEAD OF AN APPROACHING COLD FRONT. THE FRONT IS EXPECTED
TO MOVE ACROSS THE AREA LATE THURSDAY, BRINGING NUMEROUS SHOWERS
ON THURSDAY. HIGH PRESSURE RETURNS LATE FRIDAY INTO EARLY
SATURDAY. ANOTHER COLD FRONT WILL MOVE ACROSS THE AREA LATE
SATURDAY AS AN AREA OF LOW PRESSURE MOVES NORTH OF THE AREA. HIGH
PRESSURE BUILDS IN ON MONDAY, WITH A FRONTAL PASSAGE MONDAY NIGHT
INTO EARLY TUESDAY, FOLLOWED BY HIGH PRESSURE ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AT 20Z...SKIES ARE MOSTLY CLOUDY ACROSS THE REGION. AREA RADARS
SHOWING A FEW LIGHT RETURNS OVER THE UPPER DELAWARE BAY AREA...BUT
NOTHING COMING OUT OF THESE RETURNS EXCEPT FOR A FEW SPRINKLES OR
VIRGA. AIRMASS ACROSS THE REGION HAS MOISTENED OVER THE LAST 12
HOURS AS SOUTHEASTERLY WINDS BRING IN ATLANTIC MOISTURE.
THE 12Z MODELS AND VARIOUS ENSEMBLES AND HIGH RES MODEL GUIDANCE
CONTINUE TO SHOW DIFFERENCES IN TIMING OF THE N-S ORIENTED BAND
OF PRECIP THAT IS APPROACHING THE AREA AHEAD OF THE COLD.
LATEST 19Z HRRR HAS EDGE OF PRECIP AT 10Z ON THE WRN FRINGE OF THE
CWA. THE 12Z NAM ACTUALLY HANDLED THE CURRENT PLACEMENT OF PRECIP
PRETTY WELL...AND LEANED MORE ON ITS TIMING FOR PRECIP ONSET
DURATION. MODELS SHOW WINDS AT 925 AND 850 HPA INCREASING OVERNIGHT
WITH A 40-50 KT SPEED MAX MOVING WESTERN PORTIONS OF THE CWA BY
12Z/THU. SO GENERALLY EXPECTING A DRY OVERNIGHT PERIOD...WITH ONLY
CHANCE POPS ACROSS WRN ZNS BY MORNING.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
THE ZONE OF PRECIP CONSISTING OF SHOWERS WILL MOVE ACROSS THE
ENTIRE REGION DURING THE MORNING HOURS. INSTABILITY IS VERY
LIMITED SO TSTMS HAVE NOT BEEN INCLUDED IN THIS UPDATE. WHILE THE
PRECIP AREA WILL MOVE OUT DURING THE EARLY/MID AFTERNOON HOURS...
THE ACTUAL COLD FRONT WILL NOT ARRIVE UNTIL SOMETIME IN THE LATE
AFTERNOON. TEMPERATURES BEHIND THE FRONT WILL NOT FALL OFF ALL
THAT QUICKLY AS THE AIRMASS IS NOT THAT COLD.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
HIGH PRESSURE BUILDS IN ON FRIDAY AND CONTINUES INTO THE MORNING
ON SATURDAY. ANOTHER FAST MOVING...BUT MOISTURE-LIMITED COLD
FRONT WILL CROSS THE AREA SATURDAY NIGHT...AND USHER IN COOL HIGH
PRESSURE. THE LONG TERM WILL FEATURE GENERALLY HIGH PRESSURE WITH
A FEW WEAK FRONTAL SYSTEMS PASSING MAINLY NORTH OF THE AREA ON
SUNDAY AND AGAIN MONDAY NIGHT. MOISTURE IS LIMITED WITH THESE
SYSTEMS AND EXPECT THE PERIOD TO BE GENERALLY DRY.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THIS AFTERNOON...WINDS EAST TO SADDEST AT 8-12 KT WITH OVC CIGS
ABOVE 3 KFT. A FEW TERMINALS...KABE, KRDG AND KTTN HAVE CIGS
020-025 AND EXPECT THESE TO CONTINUE FOR THE NEXT 4-6 HRS. A FEW
LIGHT SPRINKLES ACROSS THE DEL BAY AREA THROUGH 22Z...OTHERWISE
DRY WEATHER THROUGH 00Z.
OVERNIGHT...GENERALLY VFR TO MVFR UNTIL 06Z...WITH SOME IFR CIGS
AT KABE, KRDG, KTTN. TOWARDS MORNING...SHOWERS WILL OVERSPREAD
THE REGION AFTER 08Z FROM WEST TO EAST...REACHING THE KPHL/KPNE
BETWEEN ROUGHLY 09-10Z. WINDS ALOFT AT 4-5 KFT WILL INCREASE TO
40-50 KTS BETWEEN 09Z-12Z WITH SOME SOUTHEASTERLY SURFACE WINDS
GUSTING 20-25KT AT TIMES DURING THE MORNING HOURS. PRECIP WILL
PRODUCE LOCALLY IFR CIGS AND VSBYS IN THE HEAVIER SHOWERS.
CONDITIONS IMPRVING THROUGHOUT THE AFTERNOON FROM WEST TO EAST
FROM MVFR/LCL IFR TO VFR BY LATE AFTERNOON.
OUTLOOK...
THURSDAY NIGHT...VFR. WINDS BECOME NW BEHIND COLD FRONT.
FRIDAY-SATURDAY...VFR. GUSTY NW WINDS 20-25 KT DURING THE DAY FRIDAY.
SATURDAY NIGHT-SUNDAY...GENERALLY VFR. CHANCE SHOWERS MID-DAY
SUNDAY MAINLY NW PORTION.
&&
.MARINE...
WILL CONTINUE SCA CONDITIONS FOR SEAS. WINDS ON THUR WILL HAVE
NEAR GALE-FORCE GUSTS DURING THE AFTERNOON...BUT NOT EXPECTING
GALE CONDITIONS TO PREDOMINATE.
OUTLOOK...
THURSDAY NIGHT...SMALL CRAFT ADVISORY IN EFFECT. CHANCE OF NEAR
GALE FORCE WINDS.
FRIDAY..SMALL CRAFT ADVISORY CONDITIONS LIKELY TO CONTINUE WITH
GUSTY NW WINDS.
FRIDAY NIGHT-SATURDAY...CONDITIONS SUBSIDE BELOW ADVISORY LEVELS.
SATURDAY NIGHT-SUNDAY...A RETURN OF SMALL CRAFT ADVISORY CONDITIONS
POSSIBLE.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 6 AM EST FRIDAY
FOR ANZ450>452.
SMALL CRAFT ADVISORY UNTIL 6 AM EST FRIDAY FOR ANZ453>455.
SMALL CRAFT ADVISORY FROM NOON THURSDAY TO 6 AM EST FRIDAY FOR
ANZ430-431.
&&
$$
SYNOPSIS...99
NEAR TERM...99
SHORT TERM...99
LONG TERM...99
AVIATION...99
MARINE...99
AREA FORECAST DISCUSSION
NWS MIAMI FL
803 PM EST THU NOV 19 2015
.UPDATE...
MINOR UPDATE TO THE GRIDS THIS EVENING, MAINLY TO ADJUST POPS FOR
CURRENT CONDITIONS. THE HRRR IS INDICATING THAT THE EAST COAST MAY
SEE LESS SHOWERS OVERNIGHT THAN PREVIOUSLY THOUGHT. HOWEVER, MOST
POPS WERE ONLY SLIGHT CHANCE TO CHANCE ANYWAYS, AND GIVEN
CONTINUED UNCERTAINTY LATER TONIGHT, HAVE LEFT FORECAST RIDE.
OTHERWISE, THE FORECAST IS PRETTY MUCH ON TRACK THIS EVENING.
&&
.PREV DISCUSSION... /ISSUED 649 PM EST THU NOV 19 2015/
AVIATION...
SHOWER CHANCES ARE FORECAST TO INCREASE FROM WEST TO EAST TONIGHT.
HOWEVER, GIVEN UNCERTAINTIES DECIDED TO KEEP JUST VCSH IN FOR THE
TERMINALS AND WILL MONITOR TRENDS. TSRA THREAT TOO LOW TO MENTION
IN THE TAFS AT THIS TIME. VFR WILL BE THE PREDOMINANT CATEGORY BUT
BRIEF MVFR IS POSSIBLE. LIGHT WINDS WILL BECOME NE 5-10 KT ON
FRIDAY. /GREGORIA
PREV DISCUSSION... /ISSUED 432 PM EST THU NOV 19 2015/
DISCUSSION...
THE MAIN STORY FOR TODAY IS THE APPROACHING COLD FRONT. IT HAS
PUSHED HIGH PRESSURE TO THE EAST, BRINGING A MORE SOUTH TO
SOUTHEASTERLY FLOW TO SOUTH FLORIDA. MOISTURE HAS REMAINED OVER
THE AREA, AND SHOWERS HAVE BEEN THE RESULT. SOME ISOLATED
THUNDERSTORMS WILL ALSO BE POSSIBLE THIS EVENING.
THE FRONT WILL MOVE INTO CENTRAL FLORIDA AND SLOWLY APPROACH THE
CWA TONIGHT. BY MID-DAY TOMORROW, THE FRONT WILL STALL, PROBABLY
JUST NORTH OF THE LAKE. THIS WILL KEEP MOISTURE AND INSTABILITY
OVER SOUTH FLORIDA THROUGH THE WEEKEND. THERE DOES LOOK TO BE
ABUNDANT CLOUD COVER ASSOCIATED WITH THE FRONT. THIS WILL POSSIBLY
SOMEWHAT HINDER CONVECTIVE DEVELOPMENT WHILE THE FRONT IS AROUND.
BUT, THIS MAY ONLY KEEP MOST CONVECTION FROM DEVELOPING INTO
THUNDERSTORMS. PWATS THROUGH AT LEAST SATURDAY WILL BE AROUND 2
INCHES. THERE WILL ALSO BE A JET STREAK MOVING OVER CENTRAL
FLORIDA BY LATE TOMORROW. THIS COULD HELP GENERATE SOME HEAVY RAIN
OVERNIGHT FRIDAY INTO SATURDAY. THERE IS, OF COURSE, UNCERTAINTY
WITH TIMING AND LOCATION OF THE JET, AND ANY SMALL CHANGE WILL
CHANGE THIS. STILL HAVE SCATTERED SHOWERS FOR MOST OF THE WEEKEND,
ALONG WITH A SLIGHT CHANCE OF THUNDERSTORMS.
BY SATURDAY EVENING, ANOTHER JET MAY MOVE INTO THE AREA. THE GFS
KEEP IT FURTHER NORTH, BUT THE ECMWF BRINGS IT CLOSE ENOUGH THAT
IT BRINGS ADDITIONAL CHANCES OF HEAVY RAIN. LOOKING AT THE 5 DAY
PRECIP TOTAL FROM WPC, THE HEAVIEST ACCUMULATIONS WILL BE WELL OFF
SHORE OF THE TREASURE COAST. BUT, THEY STILL HAVE 2 INCHES OVER
PORTIONS OF THE CWA OVER THE NEXT 5 DAYS. THE 24 HOUR TOTALS ARE
GENERALLY BETWEEN A HALF INCH AND ONE INCH. SO, HAVE KEPT THINGS
JUST AS TYPICAL SCATTERED SHOWERS FOR NOW.
THE FRONT WILL BEGIN TO PUSH THROUGH ON SUNDAY. THIS WILL HAVE THE
POTENTIAL TO BE THE BUSIEST WEATHER DAY, AS THE FRONT WILL BE
FAIRLY STRONG. THE PWATS WILL GO FROM AROUND 2 INCHES AHEAD OF IT
DOWN TO AROUND THREE QUARTERS OF AN INCH BEHIND IT. THE MODELS ARE
INDICATING THE FRONT SHOULD BE THROUGH THE CWA IN THE MIDDLE OF
THE NIGHT, SUNDAY NIGHT. THE WIND SLOWLY PICKS UP, GENERALLY
BEHIND THE FRONT. THE BIGGEST QUESTION IS HOW WILL THE CLOUD COVER
AFFECT THE CONVECTION ASSOCIATED WITH THE FRONT. CURRENTLY, WENT
WITH LIKELY POPS SUNDAY. LIKELY SOME SCATTERED SHOWERS AHEAD OF
THE FRONT, AND A LINE OF SHOWERS, POSSIBLY THUNDERSTORMS, ALONG
THE FRONT.
BEHIND THE FRONT, A COOLER, DRIER AIR MASS SETTLES IN. FORECAST
HIGHS MONDAY ARE IN THE LOW TO MID 70S, WITH DEW POINTS IN THE 50S
AND 60S. BY TUESDAY MORNING, THE FORECAST LOWS ARE ARE IN THE MID
50S TO LOW 60S ACROSS SOUTH FLORIDA, WITH THE COLDER TEMPS WEST OF
THE LAKE. AS HIGH PRESSURE SETTLES IN TO THE NORTH, BEHIND THE
FRONT, WE WILL SEE AN EASTERLY FLOW RETURN, AS WELL AS A GRADUAL
WARM UP BY THE END OF THE WEEK.
MARINE...
A COLD FRONT WILL STALL JUST TO THE NORTH OF THE AREA BY TOMORROW.
THIS WILL BRING CONTINUED UNSETTLED WEATHER TO ALL SOUTH FLORIDA
WATERS OVER THE WEEKEND. THE FRONT WILL PUSH THROUGH THE AREA
SUNDAY NIGHT. THIS WILL BRING A SIGNIFICANT INCREASE IN WINDS AND
WILL LIKELY CAUSE HAZARDOUS MARINE CONDITIONS FOR ALL SOUTH
FLORIDA WATERS BY MONDAY, AS WELL AS BRING THE RETURN OF A HIGH
RISK OF RIP CURRENTS TO THE ATLANTIC BEACHES BY MONDAY, FOR A GOOD
PART OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 84 74 82 / 60 50 50 70
FORT LAUDERDALE 73 84 73 82 / 50 50 50 70
MIAMI 75 85 73 83 / 40 50 50 60
NAPLES 73 86 71 82 / 50 50 40 60
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...13/SI
LONG TERM....13/SI
AREA FORECAST DISCUSSION
NWS MIAMI FL
109 PM EST WED NOV 18 2015
.AVIATION...
TODAY HAS BEEN A VERY QUESTIONABLE DAY WITH RESPECT TO ANY
CONVECTIVE DEVELOPMENT. MODELS CONTINUE TO SHOW SHOWERS DEVELOPING
ACROSS THE AREA THROUGH THE AFTERNOON, BUT RADAR AND SATELLITE
SHOW THEY ARE HAVING A HARD TIME GETTING GOING. SO, HAVE KEPT A
RELUCTANT VCSH IN THE TAFS, BUT LIKELY WILL NOT SEE MUCH IN THE
WAY OF SHOWER ACTIVITY, LET ALONE ANY THUNDERSTORMS. THE BREEZY
CONDITIONS SHOULD ALSO BE WINDING DOWN TONIGHT, AND THE WIND WILL
BE SOMEWHAT WEAKER TOMORROW. VFR TO MVFR CONDITIONS ARE FORECAST
THROUGH THE TAF PERIOD, WITH SOME BRIEF IFR CEILINGS POSSIBLE, BUT
NOT ENOUGH TO ADD TO THE TAFS AT THIS TIME.
&&
PREV DISCUSSION... /ISSUED 354 AM EST WED NOV 18 2015/
SHORT TERM (TODAY-FRI NIGHT)...
TODAY...AS THE WIND PROFILE VEERS SLIGHTLY TODAY TO THE SE, IN
RESPONSE TO THE DEEP TROUGH ACROSS THE CENTRAL US AND WESTERN
GULF COLD FRONT, A SOMEWHAT MORE MOIST AND UNSTABLE AIR MASS WILL
BE DRAWN INTO THE ATLANTIC WATERS. MODEL PWATS RISE TDY AND ARE
CLOSE TO 2" BY 0Z THURS. HRRR AND OTHER HI RES MODELS ARE MUCH
MORE AGGRESSIVE WITH SHOWERS AND RAINFALL AMOUNTS ALONG THE EAST
COAST TODAY, THAN YESTERDAY. THIS IS IN STARK CONTRAST TO THE
RATHER DRY NAM/GFS. MOST ACTIVITY IS DEPICTED ACROSS BROWARD AND
PALM BEACH COUNTIES DURING THE MORNING. DESPITE THE UNCERTAINTY
BETWEEN GUIDANCE, STILL CAN`T RULE OUT SOME DEEPER SHOWERS
TRAINING OVER PARTS OF THE EAST COAST PRODUCING HVY RAINFALL. IN
ADDITION, SHOWERS MAY BE ARRIVING LATE DAY FOR
HENDRY/GLADES/COLLIER FROM THE GULF WATERS, WELL AHEAD OF THE COLD
FRONT.
TONIGHT...SURFACE FLOW CONTINUES TO VEER AND WEAKENS SLIGHTLY
OVERNIGHT. COLD FRONT SLOWS AND BEGINS TO STRETCH OUT ACROSS THE
GULF OF MEXICO. COASTAL SHOWERS REMAIN.
TOMORROW...THE TROUGH AXIS WILL ENTER THE MISSISSIPPI RIVER
VALLEY, WHICH WILL SHOVE THE RIDGE AXIS/SURFACE HIGH OFF THE EAST
COAST. THUS, THE PRESSURE GRADIENT RELAXES, WINDS CONTINUE TO
LESSEN AND THE SOUTHERLY COMPONENT INCREASES. WITH PWATS
REMAINING NEAR 2", SHOWERS CAN BE EXPECTED ACROSS THE ENTIRE
REGION.
FRIDAY...WEAK FRONT AND SUBTLE PVA ARRIVE ACROSS THE LAKE REGION.
ALTHOUGH THE FRONT STALLS, H5 TEMPS WILL DECREASE SIGNIFICANTLY
ACROSS THE WHOLE REGION. LAPSE RATES WILL BE MORE FAVORABLE. APPEARS
AS THOUGH A WEAK EAST COAST SEA BREEZE WILL DEVELOP. BETTER CHC
FOR SOME THUNDERSTORMS THIS DAY, DEVELOPING EARLY ALONG THE COAST
THEN PROGRESSING INLAND THROUGH THE DAY.
LONG TERM (SAT-WED)...
THIS WEEKEND`S FORECAST CONTINUES TO LOOK CLOUDY AND WET. FRONT IS
STATIONARY NEARBY, AND A ZONAL JET ACROSS THE GULF OF MEXICO IS ABLE
TO TRANSPORT SEVERAL DISTURBANCES INTO FL ALONG THE BOUNDARY. ECMWF
HAS SOME COPIOUS RAIN AMOUNTS ACROSS SOUTH FLORIDA ON SUNDAY, BUT
GOOD RAIN AMOUNTS ARE ALSO POSSIBLE ON SATURDAY CONSIDERING THIS
PATTERN. MAY BE SOMETHING TO WATCH. IN FACT, THE ECMWF IS NOW SLOWER
WITH THE FRONT AND IS MUCH MORE UNSETTLED ON SUNDAY COMPARED TO THE
GFS.
INCREASING CONFIDENCE NOW THAT THIS STATIONARY BOUNDARY FINALLY GETS
SHOVED THROUGH SOUTH FL INTO MONDAY. 100KT JET STREAK MOVING THROUGH
THE GULF WILL PROVIDE A SUFFICIENT BUMP. MUCH DRIER AND SOMEWHAT
COOLER AIR AGAIN LOOKS TO BE ON THE WAY BASED ON GFS/ECMWF/GEFS 0Z
SUITE INTO THE END OF THE FORECAST. THIS SHOULD BE A NOTICEABLE
CHANGE TO SAY THE LEAST AFTER A SIZZLING EARLY FALL.
MARINE...
SMALL CRAFT ADV CONTINUES FOR THE OFFSHORE GULF WATERS AND THE
ATLANTIC WATERS. WINDS WILL SUBSIDE LATER TODAY AND TONIGHT, EVEN
MORE SO BY THURSDAY NIGHT AND FRIDAY WHEN SPEEDS FALL BELOW 10
KTS. A FRONT STALLS OVER THE LOCAL WATERS THIS WEEKEND. WINDS AND
SEAS MAY BECOME HAZARDOUS AGAIN LATE THIS WEEKEND AND EARLY NEXT
WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 78 86 71 85 / 50 50 70 50
FORT LAUDERDALE 79 85 72 84 / 50 50 60 50
MIAMI 78 85 74 85 / 50 50 60 50
NAPLES 73 85 72 85 / 30 40 40 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK UNTIL 7 PM EST THIS EVENING FOR FLZ168-172-
173.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...13/SI
LONG TERM....21/KM
AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS MIAMI FL
618 AM EST WED NOV 18 2015
.UPDATE...
SHOWERS WILL CONTINUE TO DEVELOP OFFSHORE AND MOVE NEAR SOME OF
THE EAST COAST TERMINALS THIS MORNING, MOST LIKELY FLL/FXE/PBI.
SOME OF THE SHOWERS COULD CONTAIN 30 KT GUSTS AND BRIEF IFR/MVFR
CIG/VIS MAY OCCUR. SHOWERS CHANCES ARE SOMEWHAT LESS TODAY FURTHER
SOUTH/THIS AFTERNOON BUT CAN`T BE RULED OUT. VCSH WAS USED THIS
AFTERNOON AND TONIGHT. SUSTAINED WINDS FROM THE E AROUND 15 KTS
WITH 25 KT GUSTS ARE EXPECTED OUTSIDE OF SHOWERS.
&&
.PREV DISCUSSION... /ISSUED 354 AM EST WED NOV 18 2015/
SHORT TERM (TODAY-FRI NIGHT)...
TODAY...AS THE WIND PROFILE VEERS SLIGHTLY TODAY TO THE SE, IN
RESPONSE TO THE DEEP TROUGH ACROSS THE CENTRAL US AND WESTERN
GULF COLD FRONT, A SOMEWHAT MORE MOIST AND UNSTABLE AIR MASS WILL
BE DRAWN INTO THE ATLANTIC WATERS. MODEL PWATS RISE TDY AND ARE
CLOSE TO 2" BY 0Z THURS. HRRR AND OTHER HI RES MODELS ARE MUCH
MORE AGGRESSIVE WITH SHOWERS AND RAINFALL AMOUNTS ALONG THE EAST
COAST TODAY, THAN YESTERDAY. THIS IS IN STARK CONTRAST TO THE
RATHER DRY NAM/GFS. MOST ACTIVITY IS DEPICTED ACROSS BROWARD AND
PALM BEACH COUNTIES DURING THE MORNING. DESPITE THE UNCERTAINTY
BETWEEN GUIDANCE, STILL CAN`T RULE OUT SOME DEEPER SHOWERS
TRAINING OVER PARTS OF THE EAST COAST PRODUCING HVY RAINFALL. IN
ADDITION, SHOWERS MAY BE ARRIVING LATE DAY FOR
HENDRY/GLADES/COLLIER FROM THE GULF WATERS, WELL AHEAD OF THE COLD
FRONT.
TONIGHT...SURFACE FLOW CONTINUES TO VEER AND WEAKENS SLIGHTLY
OVERNIGHT. COLD FRONT SLOWS AND BEGINS TO STRETCH OUT ACROSS THE
GULF OF MEXICO. COASTAL SHOWERS REMAIN.
TOMORROW...THE TROUGH AXIS WILL ENTER THE MISSISSIPPI RIVER
VALLEY, WHICH WILL SHOVE THE RIDGE AXIS/SURFACE HIGH OFF THE EAST
COAST. THUS, THE PRESSURE GRADIENT RELAXES, WINDS CONTINUE TO
LESSEN AND THE SOUTHERLY COMPONENT INCREASES. WITH PWATS
REMAINING NEAR 2", SHOWERS CAN BE EXPECTED ACROSS THE ENTIRE
REGION.
FRIDAY...WEAK FRONT AND SUBTLE PVA ARRIVE ACROSS THE LAKE REGION.
ALTHOUGH THE FRONT STALLS, H5 TEMPS WILL DECREASE SIGNIFICANTLY
ACROSS THE WHOLE REGION. LAPSE RATES WILL BE MORE FAVORABLE. APPEARS
AS THOUGH A WEAK EAST COAST SEA BREEZE WILL DEVELOP. BETTER CHC
FOR SOME THUNDERSTORMS THIS DAY, DEVELOPING EARLY ALONG THE COAST
THEN PROGRESSING INLAND THROUGH THE DAY.
LONG TERM (SAT-WED)...
THIS WEEKEND`S FORECAST CONTINUES TO LOOK CLOUDY AND WET. FRONT IS
STATIONARY NEARBY, AND A ZONAL JET ACROSS THE GULF OF MEXICO IS ABLE
TO TRANSPORT SEVERAL DISTURBANCES INTO FL ALONG THE BOUNDARY. ECMWF
HAS SOME COPIOUS RAIN AMOUNTS ACROSS SOUTH FLORIDA ON SUNDAY, BUT
GOOD RAIN AMOUNTS ARE ALSO POSSIBLE ON SATURDAY CONSIDERING THIS
PATTERN. MAY BE SOMETHING TO WATCH. IN FACT, THE ECMWF IS NOW SLOWER
WITH THE FRONT AND IS MUCH MORE UNSETTLED ON SUNDAY COMPARED TO THE
GFS.
INCREASING CONFIDENCE NOW THAT THIS STATIONARY BOUNDARY FINALLY GETS
SHOVED THROUGH SOUTH FL INTO MONDAY. 100KT JET STREAK MOVING THROUGH
THE GULF WILL PROVIDE A SUFFICIENT BUMP. MUCH DRIER AND SOMEWHAT
COOLER AIR AGAIN LOOKS TO BE ON THE WAY BASED ON GFS/ECMWF/GEFS 0Z
SUITE INTO THE END OF THE FORECAST. THIS SHOULD BE A NOTICEABLE
CHANGE TO SAY THE LEAST AFTER A SIZZLING EARLY FALL.
MARINE...
SMALL CRAFT ADV CONTINUES FOR THE OFFSHORE GULF WATERS AND THE
ATLANTIC WATERS. WINDS WILL SUBSIDE LATER TODAY AND TONIGHT, EVEN
MORE SO BY THURSDAY NIGHT AND FRIDAY WHEN SPEEDS FALL BELOW 10
KTS. A FRONT STALLS OVER THE LOCAL WATERS THIS WEEKEND. WINDS AND
SEAS MAY BECOME HAZARDOUS AGAIN LATE THIS WEEKEND AND EARLY NEXT
WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 86 78 86 71 / 50 50 50 70
FORT LAUDERDALE 85 79 85 72 / 50 50 50 60
MIAMI 87 78 85 74 / 50 50 50 60
NAPLES 89 73 85 72 / 20 30 40 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR FLZ168-172-173.
AM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR AMZ630-
650-651-670-671.
GM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR GMZ676.
&&
$$
SHORT TERM...21/KM
LONG TERM....21/KM
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
401 AM EST WED NOV 18 2015
.DISCUSSION...
...POOR-HAZARDOUS BEACH/BOATING CONDITIONS TODAY..
...INCREASED RAIN CHANCES INTO LATE WEEK...
TODAY-TONIGHT...A RATHER STRONG HIGH PRESSURE RIDGE ALONG THE
EASTERN SEABOARD WILL ONLY SLOWLY NUDGE EAST AS A STRONG LOW
PRESSURE CENTER IN THE MID PART OF THE COUNTRY LIFTS INTO SOUTHERN
CANADA. THE SOUTHERN END OF THE ASSOCIATED COLD FRONT WILL WEAKEN
AND SLOW AS IT ENTERS THE WESTERN FLORIDA PANHANDLE TONIGHT.
QUITE STRONG PRESSURE GRADIENT THAT HAS BEEN SUPPORTING 25-30
KNOT SOUTHEAST WINDS JUST OFF THE SURFACE WILL ONLY EASE SLIGHTLY
DURING THE DAY...THEN MORESO LATE TONIGHT AS THE FRONTAL TROUGH
GETS CLOSER. SUCH BREEZY CONDITIONS WILL CONTINUE TO GENERATE
CONVERGENCE LINES OVER THE ATLANTIC AND SWEEP SHOWERS QUICKLY
ASHORE AND INLAND TODAY. THIS CONVECTION HAS BEEN RATHER SHALLOW
OVERNIGHT DUE TO MID LEVEL RIDGING. FORECAST SOUNDINGS INDICATE
LIMITED INSTABILITY AND THE HRRR HAS NOT SHOWN LIGHTNING
GENERATION YET...SO WILL LEAVE CURRENT FORECAST WHICH HAS NO
MENTION OF THUNDER.
THE 00Z MOS POPS FOR TODAY CAME IN 40-60 PERCENT WHICH IS A 20-30
PERCENT JUMP FROM THE 12Z RUN. RADAR COVERAGE OVERNIGHT LOOKS
CLOSER TO 40 PERCENT COVERAGE...SO WILL SETTLE ON THAT FOR NOW.
GRADUAL VEERING AND WEAKENING OF LOW LEVEL FLOW TONIGHT WILL
LESSEN ONSHORE MOVING SHOWERS. BUT WITH THE SOUTHEAST/SOUTH WIND
FLOW BEING VERY MOIST...WILL KEEP CHANCE MENTION OF SHOWERS
AREAWIDE.
THUR-FRI...BROAD TROUGHING WILL CARVE ITSELF OUT OVER THE EASTERN
HALF OF THE UNITED STATES AS A STORM SYSTEM PUSHES NORTH OVER THE
GREAT LAKES AND INTO CANADA. ASSOCIATED COLD FRONT WILL LOSE MUCH OF
ITS FORWARD MOMENTUM AS IT APPROACHES THE FLORIDA PENINSULA. THE
SLOW MOVING FRONT WILL SPELL A DAMP END TO THE WORKWEEK...ESPECIALLY
ON THURSDAY WHEN PWATS WILL LIKELY EXCEED 2.0 INCHES...WELL WITHIN
THE UPPER LIMITS OF CLIMATOLOGY FOR THIS TIME OF YEAR.
GENERALLY CLOUDY AND SHOWERY WEATHER EXPECTED THURSDAY OUT AHEAD OF
THE COLD FRONT. SURFACE CONVERGENCE REMAINS UNIMPRESSIVE GIVEN THE
LACK OF FORWARD MOMENTUM OF THE BOUNDARY...AND UPPER LEVEL TEMPS AND
DYNAMICS REMAIN LACKING OUTSIDE OF SOME UPPER LEVEL DIVERGENCE
ALOFT. SLIGHT CHANCE OF STORMS SEEMS PRUDENT FOR THE TIME BEING.
FRONT EXPECTED TO STALL ACROSS SOUTHERN SECTIONS OF THE CWA ON
FRIDAY AS SOME MID LEVEL DRYING MOVES IN FROM THE NORTH.
OVERALL...POPS WILL BE ONE TO TWO CATEGORIES LOWER WITH THE BEST
CHANCE OVER THE TREASURE COAST...IN THE VICINITY OF THE FRONT AND
HIGHER MOISTURE.
SAT-WED...INITIAL FRONTAL BOUNDARY LINGERS ACROSS SOUTH FLORIDA AS
WEAK LOW PRESSURE TRIES TO DEVELOP ALONG IT...PROVIDING THE AREA
WITH SOME ADDITIONAL RAIN CHANCES OVER THE WEEKEND. BEST CHANCES
REMAIN ACROSS THE SOUTHERN HALF OF THE FORECAST AREA...WHERE THE
HIGHEST MOISTURE WILL CONTINUE TO RESIDE. ADDITIONAL AMPLIFICATION
OF THE TROUGHINESS OVER THE EASTERN UNITED STATES WILL SEND A
REINFORCING COOL FRONT THROUGH THE AREA AND FINALLY BRING RAIN
CHANCES TO AN END BY LATE SUNDAY / EARLY MONDAY. HIGH PRESSURE WILL
BUILD NORTH OF THE AREA BEHIND THE SECONDARY SURFACE
BOUNDARY...INCREASING THE LOCAL PRESSURE GRADIENT WHILE VEERING OUR
WINDS QUICKLY ONSHORE. THOUGH THE FLOW WILL BE MODIFIED SOMEWHAT OFF
THE WARM ATLANTIC OCEAN...EXPECT SEVERAL DAYS OF COOLER AND DRIER
AIR TO FILTER IN OVER EAST CENTRAL FLORIDA.
&&
.AVIATION...
BREEZY SOUTHEAST WINDS WILL SWEEP ISOLATED TO SCATTERED ATLANTIC
SHOWERS ACROSS THE COAST AND INLAND TODAY. BRIEF DOWNPOURS WITH
MVFR AND GUSTY WINDS 25 TO 30 KNOTS WILL OCCUR ESPECIALLY AT THE
COASTAL TERMINALS.
&&
.MARINE...
TODAY-TONIGHT...LATEST BUOY DATA SHOWED SEAS 5 TO 8 FEET ACROSS
THE WATERS. WINDS HAVE BEEN MODULATED BY PASSING SHOWERS BUT
OVERALL THEY ARE FORECAST AT LEAST 15 TO 20 KNOTS THROUGH THE
DAY. THEREFORE WILL NOT CHANGE THE CURRENT SMALL CRAFT ADVISORY
THAT IS IN EFFECT FOR ALL THE WATERS. MARINE MOS AND OUR LOCAL
WAVE MODEL ARE SHOWING WIND/SEAS GRADUALLY DIMINISHING TONIGHT...
SO WILL NOT CHANGE THE 10 PM END TIME...THOUGH MARINE CONDITIONS
WILL REMAIN POOR IN THE OPEN ATLANTIC MOST OF THE NIGHT. SOME OF
THE QUICK MOVING SHOWERS TODAY WILL ALSO PRODUCE BRIEF 25-30 KNOT
WIND GUSTS.
THU-FRI...SLOW MOVING SURFACE FRONT WILL APPROACH THE COASTAL WATERS
ON THURSDAY BEFORE STALLING OVER SOUTH FLORIDA ON FRIDAY. SOUTHEAST
WINDS EXPECTED TO RELAX WHILE GRADUALLY VEERING SOUTHERLY OUT AHEAD
OF THE FRONT. SHOWERS ARE LIKELY ON THURSDAY IN ASSOCIATION WITH THE
FRONT...ALONG WITH ISOLATED OFFSHORE MOVING THUNDERSTORMS. WITH THE
FRONT EXPECTED TO HANG UP ACROSS OUR SOUTHERN AREAS ON FRIDAY...WIND
AND SEAS FORECAST WILL BE A BIT TRICKY...HOWEVER...GENERAL THINKING
IS WINDS WILL BECOME NORTH/NORTHEASTERLY WHILE GRADUALLY INCREASING
UP TO 15 KNOTS DURING THE AFTERNOON.
SAT-SUN...SURFACE FRONT WILL LINGER ACROSS SOUTHERN AREAS WHILE WEAK
LOW PRESSURE TRIES TO DEVELOP ALONG THE BOUNDARY. FORECAST REMAINS
CHALLENGING...HOWEVER...A GRADUAL RELAXATION OF WINDS IS EXPECTED ON
SATURDAY BEFORE A REINFORCING COOL FRONT QUICKLY BUILDS SEAS AND
NORTHERLY WINDS BEHIND IT ON SUNDAY INTO EARLY NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 85 73 81 69 / 40 40 60 50
MCO 86 72 83 69 / 40 30 60 50
MLB 84 75 83 72 / 40 30 60 50
VRB 85 74 84 71 / 40 30 60 60
LEE 85 72 82 68 / 40 40 60 50
SFB 86 72 83 69 / 40 40 60 50
ORL 85 72 83 69 / 40 30 60 50
FPR 84 74 83 71 / 40 30 60 60
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING 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...LASCODY
LONG TERM....ULRICH
AREA FORECAST DISCUSSION
NWS MIAMI FL
354 AM EST WED NOV 18 2015
.SHORT TERM (TODAY-FRI NIGHT)...
TODAY...AS THE WIND PROFILE VEERS SLIGHTLY TODAY TO THE SE, IN
RESPONSE TO THE DEEP TROUGH ACROSS THE CENTRAL US AND WESTERN
GULF COLD FRONT, A SOMEWHAT MORE MOIST AND UNSTABLE AIRMASS WILL
BE DRAWN INTO THE ATLANTIC WATERS. MODEL PWATS RISE TDY AND ARE
CLOSE TO 2" BY 0Z THURS. HRRR AND OTHER HI RES MODELS ARE MUCH
MORE AGGRESSIVE WITH SHOWERS AND RAINFALL AMOUNTS ALONG THE EAST
COAST TODAY, THAN YESTERDAY. THIS IS IN STARK CONTRAST TO THE
RATHER DRY NAM/GFS. MOST ACTIVITY IS DEPICTED ACROSS BROWARD AND
PALM BEACH COUNTIES DURING THE MORNING. DESPITE THE UNCERTAINTY
BETWEEN GUIDANCE, STILL CAN`T RULE OUT SOME DEEPER SHOWERS
TRAINING OVER PARTS OF THE EAST COAST PRODUCING HVY RAINFALL. IN
ADDITION, SHOWERS MAY BE ARRIVING LATE DAY FOR
HENDRY/GLADES/COLLIER FROM THE GULF WATERS, WELL AHEAD OF THE COLD
FRONT.
TONIGHT...SURFACE FLOW CONTINUES TO VEER AND WEAKENS SLIGHTLY
OVERNIGHT. COLD FRONT SLOWS AND BEGINS TO STRETCH OUT ACROSS THE
GULF OF MEXICO. COASTAL SHOWERS REMAIN.
TOMORROW...THE TROUGH AXIS WILL ENTER THE MISSISSIPPI RIVER
VALLEY, WHICH WILL SHOVE THE RIDGE AXIS/SURFACE HIGH OFF THE EAST
COAST. THUS, THE PRESSURE GRADIENT RELAXES, WINDS CONTINUE TO
LESSEN AND THE SOUTHERLY COMPONENT INCREASES. WITH PWATS
REMAINING NEAR 2", SHOWERS CAN BE EXPECTED ACROSS THE ENTIRE
REGION.
FRIDAY...WEAK FRONT AND SUBTLE PVA ARRIVE ACROSS THE LAKE REGION.
ALTHOUGH THE FRONT STALLS, H5 TEMPS WILL DECREASE SIGNIFICANTLY
ACROSS THE WHOLE REGION. LAPSE RATES WILL BE MORE FAVORABLE. APPEARS
AS THOUGH A WEAK EAST COAST SEA BREEZE WILL DEVELOP. BEETER CHC
FOR SOME THUNDERSTORMS THIS DAY, DEVELOPING EARLY ALONG THE COAST
THEN PROGRESSING INLAND THROUGH THE DAY.
.LONG TERM (SAT-WED)...
THIS WEEKEND`S FORECAST CONTINUES TO LOOK CLOUDY AND WET. FRONT IS
STATIONARY NEARBY, AND A ZONAL JET ACROSS THE GULF OF MEXICO IS ABLE
TO TRANSPORT SEVERAL DISTURBANCES INTO FL ALONG THE BOUNDARY. ECMWF
HAS SOME COPIUS RAIN AMOUNTS ACROSS SOUTH FLORIDA ON SUNDAY, BUT
GOOD RAIN AMOUNTS ARE ALSO POSSIBLE ON SATURDAY CONSIDERING THIS
PATTERN. MAY BE SOMETHING TO WATCH. IN FACT, THE ECMWF IS NOW SLOWER
WITH THE FRONT AND IS MUCH MORE UNSETTLED ON SUNDAY COMPARED TO THE
GFS.
INCREASING CONFIDENCE NOW THAT THIS STATIONARY BOUNDARY FINALLY GETS
SHOVED THROUGH SOUTH FL INTO MONDAY. 100KT JET STREAK MOVING THROUGH
THE GULF WILL PROVIDE A SUFFICIENT BUMP. MUCH DRIER AND SOMEWHAT
COOLER AIR AGAIN LOOKS TO BE ON THE WAY BASED ON GFS/ECMWF/GEFS 0Z
SUITE INTO THE END OF THE FORECAST. THIS SHOULD BE A NOTICEABLE
CHANGE TO SAY THE LEAST AFTER A SIZZLING EARLY FALL.
&&
.MARINE...
SMALL CRAFT ADV CONTINUES FOR THE OFFSHORE GULF WATERS AND THE
ATLANTIC WATERS. WINDS WILL SUBSIDE LATER TODAY AND TONIGHT, EVEN
MORE SO BY THURSDAY NIGHT AND FRIDAY WHEN SPEEDS FALL BELOW 10
KTS. A FRONT STALLS OVER THE LOCAL WATERS THIS WEEKEND. WINDS AND
SEAS MAY BECOME HAZARDOUS AGAIN LATE THIS WEEKEND AND EARLY NEXT
WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 86 78 86 71 / 50 50 50 70
FORT LAUDERDALE 85 79 85 72 / 50 50 50 60
MIAMI 87 78 85 74 / 50 50 50 60
NAPLES 89 73 85 72 / 20 30 40 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR FLZ168-172-173.
AM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR AMZ650-
651-670-671.
GM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR GMZ676.
&&
$$
SHORT TERM...21/KM
LONG TERM....21/KM
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
313 PM CST WED NOV 18 2015
.SHORT TERM...(Tonight)
ISSUED AT 313 PM CST WED NOV 18 2015
20z/2pm surface chart shows 980mb low over southwest Ontario, with a
cold front extending southeastward into the Ohio River Valley. A
secondary front/trough axis is noted further west along/just west of
the Mississippi River. This second feature will swing through
central Illinois this evening, accompanied by clouds and wind, but
no precip. Southerly winds have been gusting to between 30 and 40
mph this afternoon, but will veer to the southwest this evening then
to the west late tonight as the trough passes. Forecast soundings
suggest mostly cloudy skies early on will eventually give way to
clearing from west to east overnight. Due to cloud cover for a good
portion of the night and continued gusty winds, have gone a few
degrees above MAV guidance numbers, with lows ranging from the
middle 30s northwest of the Illinois River to the lower 40s
along/south of I-70.
&&
.LONG TERM...(Thursday through Wednesday)
ISSUED AT 313 PM CST WED NOV 18 2015
Morning upper air shows upper trough to move east across area today,
gradually bringing drier air aloft in.
Next system is a low pressure center to move into the area friday
night into saturday. Model differences though on the track. Nam
model at 12z looked to be preferred model which was further north
acorss northern central IL with the main snow area over northern IL
and southern WI. 18z NAM is now slower, but still in the northern
track. Plenty of cold air and during the overnight hours friday
night makes the best area for light snow on friday night and
saturday morning, over the northern half of the CWA with light
accumulations expected. Because this possibly being the first
measureable snow of year, will need to continue to watch the changes
in the model. Coordination and colaboration with WPC and surrounding
offices done in graphics and chatroom.
After a cool remainder of the weekend and start of the workweek,
some warming, but another warm advection rain event possible into
Wednesday. Amounts look to be light at this time, but still early.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 1204 PM CST WED NOV 18 2015
Dry slot associated with upper low over northeast Iowa is
currently working its way into west-central Illinois and will
gradually push eastward across the remainder of the area this
afternoon. End result will be VFR ceilings or even a temporary
loss of ceilings...especially at KSPI where 1730z visible
satellite imagery shows partial clearing just off to the west.
Main aviation weather forecast challenge will be timing the return
of MVFR ceilings currently poised upstream across Missouri. HRRR
suggests these clouds will arrive at KPIA and KSPI between 21z
and 22z...but the bigger question is whether they will reach the
easternmost terminals at all. While the HRRR seems to think so,
NAM forecast soundings keep ceilings a bit higher further east.
Based on current trajectory of clouds, have opted to maintain low
VFR ceilings at both KDEC and KCMI late this afternoon into the
evening. Clouds clear from west to east by mid to late evening,
leaving behind clear skies across the board by Thursday morning.
Other concern is the strong winds. Southerly winds gusting to
between 30 and 35kt this afternoon will veer to the southwest and
decrease to less than 25kt this evening. Once the sun comes up,
westerly wind gusts will increase back into the 25 to 30kt range
by Thursday morning.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Goetsch
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1204 PM CST WED NOV 18 2015
.UPDATE...
ISSUED AT 955 AM CST WED NOV 18 2015
Made a few quick updates to the forecast earlier this morning to
lower PoPs, as the steady/heavy rain has now shifted well to the
east into Indiana. 1543z radar imagery shows very little precip in
the KILX CWA other than perhaps a few isolated showers. While an
initial cold front has now passed to the east, the main push of
colder air remains to the west across western Iowa/Missouri.
Before the primary cold front arrives later this afternoon, gusty
southerly winds will keep temperatures on the mild side in the
upper 50s/lower 60s. May even see some partial clearing for a time
across the southern half of the CWA from late morning through mid-
afternoon as a pronounced mid-level dry slot seen on latest
visible satellite imagery from Arkansas into west-central Illinois
traverses eastward across the area. Latest zone update has already
been issued.
&&
.SHORT TERM...(Today)
ISSUED AT 229 AM CST WED NOV 18 2015
Strong low pressure area will continue to lift northward today and
reach northern MN by late this afternoon. Pcpn associated with this
system over the CWA will continue moving north while the whole area
of pcpn slowly moves east through the morning. This will keep some
moderate rain and isolated thunderstorms moving across eastern IL
this morning. Flood Watch still continues until 6am but have trimmed
off quite a few counties and just left the eastern and southeastern
counties in the watch til 6am. Watch will be allowed to expire at
6am and based on radar trends, thinking is most of the heaviest pcpn
will be east of the area by 6am. With center of low pressure area
being a 989mb low, pressure gradient is very tight, so expecting
very gusty winds today, with gusts to around 40 mph possible from
late this morning into the afternoon. Winds will decrease late
afternoon and into the evening. Gusty southeast, becoming
south/southwest winds will allow temps to climb back to the lower
60s in the east and mid to upper 50s in the west. Given current
conditions of warm temps...pcpn...and thick cloud cover, forecasted
high temps not far from current temps. So steady temps in some areas
will be common.
.LONG TERM...(Tonight through Tuesday)
ISSUED AT 229 AM CST WED NOV 18 2015
Now that we are getting this rain system out of the way, focus
shifts to some wintry precipitation potential for late in the week.
Upper air pattern will be transitioning to a broad trough that
covers most of the CONUS. Initial surge of cold air coming down from
Canada will glance by Illinois to the north on Thursday, but a more
prominent surge will drop southward on Friday. A fast moving
shortwave accompanying it will bring a period of precipitation to
the Midwest late in the week. The models have been settling on this
scenario the last few runs, but the exact placement and track has
been shifting some during the process. The latest ECMWF model has
slowed the cold air surge by about 6 hours, with its soundings
favoring more of a rain or rain/snow mix scenario Friday night
before changing to snow. The GFS continues with its faster surge of
colder air, favoring a quick changeover from rain to snow Friday
evening, although it also is much faster and weaker with the
precipitation and concentrates it all Friday night. The tail end of
the NAM appears too slow which keeps everything to our west until
Saturday, and the Canadian model is fairly close to the ECMWF
solution. Leaned more toward the ECMWF/Canadian consensus and
continued to focus the higher PoP`s across the northwest third of
the forecast area Friday night, with a general diminishing trend
from west to east on Saturday. Ground temperatures will hamper
accumulations in most areas aside from a light dusting, with the
better chances of seeing accumulation across the extreme northern
CWA.
The cold surge will result in highs only in the 30s across most of
the forecast area this weekend. However, the trough will shift east
quickly and transition the upper flow into more of a zonal
configuration early next week, allowing for moderating temperatures.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 1204 PM CST WED NOV 18 2015
Dry slot associated with upper low over northeast Iowa is
currently working its way into west-central Illinois and will
gradually push eastward across the remainder of the area this
afternoon. End result will be VFR ceilings or even a temporary
loss of ceilings...especially at KSPI where 1730z visible
satellite imagery shows partial clearing just off to the west.
Main aviation weather forecast challenge will be timing the return
of MVFR ceilings currently poised upstream across Missouri. HRRR
suggests these clouds will arrive at KPIA and KSPI between 21z
and 22z...but the bigger question is whether they will reach the
easternmost terminals at all. While the HRRR seems to think so,
NAM forecast soundings keep ceilings a bit higher further east.
Based on current trajectory of clouds, have opted to maintain low
VFR ceilings at both KDEC and KCMI late this afternoon into the
evening. Clouds clear from west to east by mid to late evening,
leaving behind clear skies across the board by Thursday morning.
Other concern is the strong winds. Southerly winds gusting to
between 30 and 35kt this afternoon will veer to the southwest and
decrease to less than 25kt this evening. Once the sun comes up,
westerly wind gusts will increase back into the 25 to 30kt range
by Thursday morning.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Auten
LONG TERM...Geelhart
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1143 PM CST TUE NOV 17 2015
.UPDATE...
ISSUED AT 815 PM CST TUE NOV 17 2015
Things are going about as planned this evening across central and
southeast Illinois with the current storm system. The mostly dry
period during the late afternoon/early evening has come to an end
across western sections of the forecast area as another main band
of rainfall spreads into the area. This band is expected to track
east for the rest of the night, eventually impacting the entire
area with periods of moderate to heavy rainfall. Otherwise gusty
southerly winds will persist through the night, with gusts as high
as 40 MPH likely. This southerly flow will keep temperatures very
mild for mid-November. with low temperatures no cooler than the
upper 50s.
Made a few adjustments to hourly PoPs to better reflect current
radar trends. Other parameters were in good shape and only
required a few tweaks.
&&
.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 occurring 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 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1143 PM CST TUE NOV 17 2015
Rain continues to move across the area and should affect all TAF
sites overnight, but not ending til toward morning. Gusty
southeast winds will also continue, but should see them taper off
some during the morning hours. Based on radar mosaic, am going to
keep pcpn going all night and then forecast has pcpn ending from
west to east during the morning hours. However, with cyclonic flow
remaining over the area tomorrow, VCSH is warranted at all sites
during the day...ending around 00z. South winds will increase and
become quite gusty later in the morning and continue into the
afternoon. Believe 35-40kt gusts will be possible at all sites
during the day. Cigs through the day will be MVFR, though some
sites are VFR at the moment. With low level moisture hanging
around, thinking MVFR cigs will last through the day and into the
evening. Winds will taper as well after 00z, though still have
some gusts.
&&
.ILX Watches/Warnings/Advisories...
Flood Watch until 6 AM CST Wednesday for ILZ036-040>042-047>054-
056-061>063-066>068-071>073.
&&
$$
UPDATE...BAK
SHORT TERM...07
LONG TERM...BAK
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1225 PM EST WED NOV 18 2015
.SYNOPSIS...
ISSUED AT 1225 PM EST WED NOV 18 2015
A COLD FRONT WILL SLOWLY MOVE EAST ACROSS THE AREA TODAY
ACCOMPANIED BY GUSTY WINDS AND OCCASIONAL SHOWERS. HIGHS WILL
RANGE FROM THE LOWER 60S OVER WESTERN PORTIONS OF THE AREA TO THE
UPPER 60S EAST. A FEW SHOWERS MAY PERSIST ACROSS THE AREA TONIGHT
AS A SECONDARY COLD FRONT MOVES ACROSS THE AREA. LOWS WILL BE IN
THE LOWER AND MIDDLE 40S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 413 AM EST WED NOV 18 2015
SPLIT FLOW OVER THE CENTRAL CONUS WILL TRANSITION TO A LONG WAVE
TROF EXTENDING SOUTH FROM CENTRAL CANADA INTO THIS REGION BY THU
MORNING. UPR LOW OVER KS LIFTING NNE WILL SHEAR OUT AS JET STREAK
PUSHING INTO THE PAC NW THIS MORNING DIGS UPR TROF OVER SWRN
CANADA SEWD INTO THE PLAINS. AT THE SFC... DEEP LOW OVER IA WILL
CONTINUE TO INTENSIFY AS IT LIFTS NNE INTO WRN ONTARIO. 75KT LLJ
OVER IL WILL MOVE E-NE ACROSS OUR AREA THIS MORNING RESULTING IN
WINDY CONDITIONS BUT SHALLOW MIXING DEPTHS SHOULD KEEP SFC WINDS
BLO ADVISORY CRITERIA IN THE 20-25KT/G30-35KT RANGE WITH A FEW
HIGHER GUSTS PSBL. LEFT CATEGORICAL POPS IN THE FCST CWA-WIDE AS
A FAIRLY IMPRESSIVE PLUME OF DEEP MOISTURE WILL OVERSPREAD THE
AREA AHEAD OF THE FRONT TODAY WHICH COMBINED WITH MODEST FRONTAL
CONVERGENCE SHOULD RESULT IN MEASURABLE RAINFALL OVER THE ENTIRE
CWA. THERE HAS ALSO BEEN OCNL LIGHTNING STRIKES OVER ERN PORTION
OF THE AREA OF RAIN APCHG OUR CWA AND MODELS SUGGEST WK ELEVATED
INSTABILITY WILL CONT TO ACCOMPANY THE LEADING EDGE OF THE
MOISTURE PLUME AS IT MOVES EAST THIS MORNING... SO HAVE ADDED A
SLIGHT CHC OF TSTMS TO THE FCST IN THIS TIMEFRAME. LARGE
DIFFERENCES BETWEEN NAM/GFS MOS TODAY WITH COOLER NAM/MET
SUGGESTING MUCH LESS BOUNDARY LAYER MIXING THAN GFS/MAV. NAM IS
RUNNING TOO COOL IN THE BOUNDARY LAYER ATTM... HWVR HRRR IS
SUGGESTING RAIN SPREADING EASTWARD ACROSS OUR CWA BY 18Z WHICH
WOULD LIMIT DIURNAL RISES... THUS STAYED CLOSE TO GOING FCST WITH
HIGHS EXPECTED TO RANGE FROM THE L60S WEST TO THE U60S EAST.
FRONTAL PRECIP SHOULD BE EAST OF THE CWA BY 00Z THU. LOW PRESSURE
SYSTEM MOVG EAST FROM SWRN CANADA EARLY THIS MORNING AND MERGING
WITH ONTARIO LOW TONIGHT WILL PUSH A SECONDARY CDFNT ACROSS OUR AREA
OVERNIGHT WHICH COULD CAUSE A FEW SHOWERS IF SUFFICIENT LOW LEVEL
MOISTURE REMAINS. BRISK SWLY GRADIENT WINDS SHOULD PERSIST
OVERNIGHT AND WITH SOME CLOUDINESS AND ONLY MODEST CAA... LEANED
TOWARD WARMER GUIDANCE VALUES WITH LOWS FCST IN L-M40S.
&&
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 413 AM EST WED NOV 18 2015
WINTRY CHALLENGES THIS WEEKEND TAKE CENTER STAGE THIS PACKAGE.
ANOTHER STRONG UPPER LEVEL TROF WILL RACE SOUTHEAST INTO THE WESTERN
GREAT LAKES REGION. AHEAD OF THIS SYSTEM...COOL AIR WILL BE IN PLACE
SETTING THE STAGE FOR A WINTRY MIX OF PRECIPITATION AND THE
POTENTIAL FOR ACCUMULATING SNOW. MAJOR MODEL DIFFERENCES STILL
PERSIST AMONG THE ECMWF... SREF...CANADIAN GEM AND GFS/GFS
ENSEMBLES. THE OPERATION RUN OF ECMWF HAS SHIFTED THE LOW TRACK BACK
TO THE NORTHWEST...CLOSER TO THE BEST UPPER LEVEL SUPPORT. THE ECMWF
IS THE MOST DYNAMIC RUN WITH THIS SYSTEM TAKING ON A NEGATIVE TILT
WITH THE SURFACE LOW PRESSURE DROPPING BELOW 1000 MB. THE ECMWF WAS
ABOUT 9 TO 12 HOURS SLOWER WITH THIS SYSTEM THAN THE GFS...SO TIMING
AND TRACK WAS STILL CLOUDED WITH UNCERTAINTY. THE FASTER GFS DOES
NOT SUPPORT MUCH SNOW...TOO MANY FACTORS WERE HINDERING DENDRITIC
SNOW GROWTH/DGZ INCLUDING MAX LIFT ABOVE THE DGZ AND RIMING BELOW
THE CLOUD LAYER. ALSO...WARM GROUND TEMPERATURES WILL THWART SNOW
ACCUMULATIONS. CURRENT THOUGHTS ARE AROUND AN INCH OF SNOW
ACCUMULATION FROM FAR NORTHWEST INDIANA ACROSS FAR SOUTHERN LOWER
MICHIGAN. HOWEVER...WITH THE SURFACE LOW TRACK A LITTLE FARTHER
SOUTH...SNOW AMOUNTS WOULD LIKELY BE MUCH HIGHER. BEHIND THIS
SYSTEM...THE FIRST INVASION OF ARCTIC AIR THIS SEASON WILL CAUSE
HIGHS TO BE ONLY AROUND FREEZING SUNDAY. A MARGINAL LAKE EFFECT SET
UP SUNDAY....POOR FETCH BUT GREAT DELTA T VALUES WILL QUICKLY
DIMINISH AS WINDS BACK AND INVERSION HEIGHTS FALL SUNDAY NIGHT. LOWS
SUNDAY NIGHT MAY OCCUR IN THE EVENING WITH TEMPERATURES STEADY OR
RISING OVERNIGHT. OTHERWISE...A WARMING TREND WILL BEGIN MONDAY AS
THE LONGWAVE TROF AMPLIFIES ALONG THE NORTH AMERICAN COAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1225 PM EST WED NOV 18 2015
LOW LEVEL JET 60-75 KTS OVER THE FORECAST AREA ALONG THE BOUNDARY
LAYER TROF AXIS. SECONDARY FRONTAL BOUNDARY LAGGING THE MAIN TROF
AXIS AND THIS HAS FAVORED MOMENTUM TRANSFER AND MIXING OF THE
WINDS TO THE NEAR SURFACE. ADDITIONALLY THE DRIER AIRMASS HAS
ESSENTIALLY SUPPRESSED PRECIPITATION AND THIS TOO HAS FAVORED
MIXING DOWN OF THE LOW LEVEL JET TO THE NEAR SURFACE.
CONVECTIVE INSTABILITY IS CAPPED OVER THE FORECAST AREA...WITH
BEST FOCUS TO THE SOUTH OF THE REGION. STILL NOT FAVORABLE FOR
THUNDER - AND HAVE REMOVED ALL MENTION FROM GRIDDED FORECAST AND
TERMINAL FORECASTS.
BIGGEST CONCERN IN THE NEARTERM ARE THE NUMEROUS REPORTS OF LLWS
AND TURBULENCE. HAVE INCLUDED LLWS IN BOTH TAFS FOR THE NEAR TERM
PERIOD. LOW LEVEL JET AND BOUNDARY LAYER PRESSURE GRADIENT RELAX
SIGNIFICANTLY OVERNIGHT AND AS SECONDARY FRONT PUSHES THROUGH WILL
SEE MARKED WIND SHIFT TOWARD THE END OF THE FORECAST PERIOD.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING UNTIL 11 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
SYNOPSIS...JT
SHORT TERM...JT
LONG TERM...SKIPPER
AVIATION...LEWIS
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
559 AM EST WED NOV 18 2015
.SYNOPSIS...
ISSUED AT 413 AM EST WED NOV 18 2015
A COLD FRONT WILL MOVE EAST ACROSS THE AREA TODAY ACCOMPANIED BY
A BAND OF RAIN... WINDY CONDITIONS... AND POSSIBLY A FEW THUNDERSTORMS.
HIGHS WILL RANGE FROM THE LOWER 60S OVER WESTERN PORTIONS OF THE
AREA TO THE UPPER 60S EAST. A FEW SHOWERS MAY PERSIST ACROSS THE
AREA TONIGHT AS A SECONDARY COLD FRONT MOVES ACROSS THE AREA. LOWS
WILL BE IN THE LOWER AND MIDDLE 40S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 413 AM EST WED NOV 18 2015
SPLIT FLOW OVER THE CENTRAL CONUS WILL TRANSITION TO A LONG WAVE
TROF EXTENDING SOUTH FROM CENTRAL CANADA INTO THIS REGION BY THU
MORNING. UPR LOW OVER KS LIFTING NNE WILL SHEAR OUT AS JET STREAK
PUSHING INTO THE PAC NW THIS MORNING DIGS UPR TROF OVER SWRN
CANADA SEWD INTO THE PLAINS. AT THE SFC... DEEP LOW OVER IA WILL
CONTINUE TO INTENSIFY AS IT LIFTS NNE INTO WRN ONTARIO. 75KT LLJ
OVER IL WILL MOVE E-NE ACROSS OUR AREA THIS MORNING RESULTING IN
WINDY CONDITIONS BUT SHALLOW MIXING DEPTHS SHOULD KEEP SFC WINDS
BLO ADVISORY CRITERIA IN THE 20-25KT/G30-35KT RANGE WITH A FEW
HIGHER GUSTS PSBL. LEFT CATEGORICAL POPS IN THE FCST CWA-WIDE AS
A FAIRLY IMPRESSIVE PLUME OF DEEP MOISTURE WILL OVERSPREAD THE
AREA AHEAD OF THE FRONT TODAY WHICH COMBINED WITH MODEST FRONTAL
CONVERGENCE SHOULD RESULT IN MEASURABLE RAINFALL OVER THE ENTIRE
CWA. THERE HAS ALSO BEEN OCNL LIGHTNING STRIKES OVER ERN PORTION
OF THE AREA OF RAIN APCHG OUR CWA AND MODELS SUGGEST WK ELEVATED
INSTABILITY WILL CONT TO ACCOMPANY THE LEADING EDGE OF THE
MOISTURE PLUME AS IT MOVES EAST THIS MORNING... SO HAVE ADDED A
SLIGHT CHC OF TSTMS TO THE FCST IN THIS TIMEFRAME. LARGE
DIFFERENCES BETWEEN NAM/GFS MOS TODAY WITH COOLER NAM/MET
SUGGESTING MUCH LESS BOUNDARY LAYER MIXING THAN GFS/MAV. NAM IS
RUNNING TOO COOL IN THE BOUNDARY LAYER ATTM... HWVR HRRR IS
SUGGESTING RAIN SPREADING EASTWARD ACROSS OUR CWA BY 18Z WHICH
WOULD LIMIT DIURNAL RISES... THUS STAYED CLOSE TO GOING FCST WITH
HIGHS EXPECTED TO RANGE FROM THE L60S WEST TO THE U60S EAST.
FRONTAL PRECIP SHOULD BE EAST OF THE CWA BY 00Z THU. LOW PRESSURE
SYSTEM MOVG EAST FROM SWRN CANADA EARLY THIS MORNING AND MERGING
WITH ONTARIO LOW TONIGHT WILL PUSH A SECONDARY CDFNT ACROSS OUR AREA
OVERNIGHT WHICH COULD CAUSE A FEW SHOWERS IF SUFFICIENT LOW LEVEL
MOISTURE REMAINS. BRISK SWLY GRADIENT WINDS SHOULD PERSIST
OVERNIGHT AND WITH SOME CLOUDINESS AND ONLY MODEST CAA... LEANED
TOWARD WARMER GUIDANCE VALUES WITH LOWS FCST IN L-M40S.
&&
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 413 AM EST WED NOV 18 2015
WINTRY CHALLENGES THIS WEEKEND TAKE CENTER STAGE THIS PACKAGE.
ANOTHER STRONG UPPER LEVEL TROF WILL RACE SOUTHEAST INTO THE WESTERN
GREAT LAKES REGION. AHEAD OF THIS SYSTEM...COOL AIR WILL BE IN PLACE
SETTING THE STAGE FOR A WINTRY MIX OF PRECIPITATION AND THE
POTENTIAL FOR ACCUMULATING SNOW. MAJOR MODEL DIFFERENCES STILL
PERSIST AMONG THE ECMWF... SREF...CANADIAN GEM AND GFS/GFS
ENSEMBLES. THE OPERATION RUN OF ECMWF HAS SHIFTED THE LOW TRACK BACK
TO THE NORTHWEST...CLOSER TO THE BEST UPPER LEVEL SUPPORT. THE ECMWF
IS THE MOST DYNAMIC RUN WITH THIS SYSTEM TAKING ON A NEGATIVE TILT
WITH THE SURFACE LOW PRESSURE DROPPING BELOW 1000 MB. THE ECMWF WAS
ABOUT 9 TO 12 HOURS SLOWER WITH THIS SYSTEM THAN THE GFS...SO TIMING
AND TRACK WAS STILL CLOUDED WITH UNCERTAINTY. THE FASTER GFS DOES
NOT SUPPORT MUCH SNOW...TOO MANY FACTORS WERE HINDERING DENDRITIC
SNOW GROWTH/DGZ INCLUDING MAX LIFT ABOVE THE DGZ AND RIMING BELOW
THE CLOUD LAYER. ALSO...WARM GROUND TEMPERATURES WILL THWART SNOW
ACCUMULATIONS. CURRENT THOUGHTS ARE AROUND AN INCH OF SNOW
ACCUMULATION FROM FAR NORTHWEST INDIANA ACROSS FAR SOUTHERN LOWER
MICHIGAN. HOWEVER...WITH THE SURFACE LOW TRACK A LITTLE FARTHER
SOUTH...SNOW AMOUNTS WOULD LIKELY BE MUCH HIGHER. BEHIND THIS
SYSTEM...THE FIRST INVASION OF ARCTIC AIR THIS SEASON WILL CAUSE
HIGHS TO BE ONLY AROUND FREEZING SUNDAY. A MARGINAL LAKE EFFECT SET
UP SUNDAY....POOR FETCH BUT GREAT DELTA T VALUES WILL QUICKLY
DIMINISH AS WINDS BACK AND INVERSION HEIGHTS FALL SUNDAY NIGHT. LOWS
SUNDAY NIGHT MAY OCCUR IN THE EVENING WITH TEMPERATURES STEADY OR
RISING OVERNIGHT. OTHERWISE...A WARMING TREND WILL BEGIN MONDAY AS
THE LONGWAVE TROF AMPLIFIES ALONG THE NORTH AMERICAN COAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 554 AM EST WED NOV 18 2015
75KT LLJ OVER THE AREA THIS MORNING WILL MOVE TO THE
EAST THIS AFTN BUT MIXING WILL ALSO INCREASE WITH FROPA THIS AFTN...
SO GUSTS IN THE 30-35KT RANGE PSBL THROUGH THE DAY... WITH A FEW
HIGHER GUSTS PSBL. SHALLOW BOUNDARY LAYER MIXING THIS
MORNING MAY RESULT IN SGFNT LLWS. SCT SHRA AND A FEW TS OVER NWRN
INDIANA SHOULD BE E-NE OF SBN BY 12Z WITH THE MORE SOLID BAND OF
RAIN TO THE WEST OVERSPREADING NRN INDIANA THIS MORNING. ISOLATED
TS REMAIN A POSSIBILITY THIS MORNING BUT TOO SMALL OF A POINT CHC
TO MENTION IN TAFS. STILL EXPECT CONDITIONS TO LOWER TO MVFR AS
FRONT MOVES THROUGH AND CONTG POST FRONTAL INTO THIS EVE WITH
CONDITIONS IMPROVING BY THIS TIME THU.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING UNTIL 11 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
SYNOPSIS...JT
SHORT TERM...JT
LONG TERM...SKIPPER
AVIATION...JT
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
444 AM EST WED NOV 18 2015
.SYNOPSIS...
ISSUED AT 413 AM EST WED NOV 18 2015
A COLD FRONT WILL MOVE EAST ACROSS THE AREA TODAY ACCOMPANIED BY
A BAND OF RAIN... WINDY CONDITIONS... AND POSSIBLY A FEW THUNDERSTORMS.
HIGHS WILL RANGE FROM THE LOWER 60S OVER WESTERN PORTIONS OF THE
AREA TO THE UPPER 60S EAST. A FEW SHOWERS MAY PERSIST ACROSS THE
AREA TONIGHT AS A SECONDARY COLD FRONT MOVES ACROSS THE AREA. LOWS
WILL BE IN THE LOWER AND MIDDLE 40S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 413 AM EST WED NOV 18 2015
SPLIT FLOW OVER THE CENTRAL CONUS WILL TRANSITION TO A LONG WAVE
TROF EXTENDING SOUTH FROM CENTRAL CANADA INTO THIS REGION BY THU
MORNING. UPR LOW OVER KS LIFTING NNE WILL SHEAR OUT AS JET STREAK
PUSHING INTO THE PAC NW THIS MORNING DIGS UPR TROF OVER SWRN
CANADA SEWD INTO THE PLAINS. AT THE SFC... DEEP LOW OVER IA WILL
CONTINUE TO INTENSIFY AS IT LIFTS NNE INTO WRN ONTARIO. 75KT LLJ
OVER IL WILL MOVE E-NE ACROSS OUR AREA THIS MORNING RESULTING IN
WINDY CONDITIONS BUT SHALLOW MIXING DEPTHS SHOULD KEEP SFC WINDS
BLO ADVISORY CRITERIA IN THE 20-25KT/G30-35KT RANGE WITH A FEW
HIGHER GUSTS PSBL. LEFT CATEGORICAL POPS IN THE FCST CWA-WIDE AS
A FAIRLY IMPRESSIVE PLUME OF DEEP MOISTURE WILL OVERSPREAD THE
AREA AHEAD OF THE FRONT TODAY WHICH COMBINED WITH MODEST FRONTAL
CONVERGENCE SHOULD RESULT IN MEASURABLE RAINFALL OVER THE ENTIRE
CWA. THERE HAS ALSO BEEN OCNL LIGHTNING STRIKES OVER ERN PORTION
OF THE AREA OF RAIN APCHG OUR CWA AND MODELS SUGGEST WK ELEVATED
INSTABILITY WILL CONT TO ACCOMPANY THE LEADING EDGE OF THE
MOISTURE PLUME AS IT MOVES EAST THIS MORNING... SO HAVE ADDED A
SLIGHT CHC OF TSTMS TO THE FCST IN THIS TIMEFRAME. LARGE
DIFFERENCES BETWEEN NAM/GFS MOS TODAY WITH COOLER NAM/MET
SUGGESTING MUCH LESS BOUNDARY LAYER MIXING THAN GFS/MAV. NAM IS
RUNNING TOO COOL IN THE BOUNDARY LAYER ATTM... HWVR HRRR IS
SUGGESTING RAIN SPREADING EASTWARD ACROSS OUR CWA BY 18Z WHICH
WOULD LIMIT DIURNAL RISES... THUS STAYED CLOSE TO GOING FCST WITH
HIGHS EXPECTED TO RANGE FROM THE L60S WEST TO THE U60S EAST.
FRONTAL PRECIP SHOULD BE EAST OF THE CWA BY 00Z THU. LOW PRESSURE
SYSTEM MOVG EAST FROM SWRN CANADA EARLY THIS MORNING AND MERGING
WITH ONTARIO LOW TONIGHT WILL PUSH A SECONDARY CDFNT ACROSS OUR AREA
OVERNIGHT WHICH COULD CAUSE A FEW SHOWERS IF SUFFICIENT LOW LEVEL
MOISTURE REMAINS. BRISK SWLY GRADIENT WINDS SHOULD PERSIST
OVERNIGHT AND WITH SOME CLOUDINESS AND ONLY MODEST CAA... LEANED
TOWARD WARMER GUIDANCE VALUES WITH LOWS FCST IN L-M40S.
&&
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 413 AM EST WED NOV 18 2015
WINTRY CHALLENGES THIS WEEKEND TAKE CENTER STAGE THIS PACKAGE.
ANOTHER STRONG UPPER LEVEL TROF WILL RACE SOUTHEAST INTO THE WESTERN
GREAT LAKES REGION. AHEAD OF THIS SYSTEM...COOL AIR WILL BE IN PLACE
SETTING THE STAGE FOR A WINTRY MIX OF PRECIPITATION AND THE
POTENTIAL FOR ACCUMULATING SNOW. MAJOR MODEL DIFFERENCES STILL
PERSIST AMONG THE ECMWF... SREF...CANADIAN GEM AND GFS/GFS
ENSEMBLES. THE OPERATION RUN OF ECMWF HAS SHIFTED THE LOW TRACK BACK
TO THE NORTHWEST...CLOSER TO THE BEST UPPER LEVEL SUPPORT. THE ECMWF
IS THE MOST DYNAMIC RUN WITH THIS SYSTEM TAKING ON A NEGATIVE TILT
WITH THE SURFACE LOW PRESSURE DROPPING BELOW 1000 MB. THE ECMWF WAS
ABOUT 9 TO 12 HOURS SLOWER WITH THIS SYSTEM THAN THE GFS...SO TIMING
AND TRACK WAS STILL CLOUDED WITH UNCERTAINTY. THE FASTER GFS DOES
NOT SUPPORT MUCH SNOW...TOO MANY FACTORS WERE HINDERING DENDRITIC
SNOW GROWTH/DGZ INCLUDING MAX LIFT ABOVE THE DGZ AND RIMING BELOW
THE CLOUD LAYER. ALSO...WARM GROUND TEMPERATURES WILL THWART SNOW
ACCUMULATIONS. CURRENT THOUGHTS ARE AROUND AN INCH OF SNOW
ACCUMULATION FROM FAR NORTHWEST INDIANA ACROSS FAR SOUTHERN LOWER
MICHIGAN. HOWEVER...WITH THE SURFACE LOW TRACK A LITTLE FARTHER
SOUTH...SNOW AMOUNTS WOULD LIKELY BE MUCH HIGHER. BEHIND THIS
SYSTEM...THE FIRST INVASION OF ARCTIC AIR THIS SEASON WILL CAUSE
HIGHS TO BE ONLY AROUND FREEZING SUNDAY. A MARGINAL LAKE EFFECT SET
UP SUNDAY....POOR FETCH BUT GREAT DELTA T VALUES WILL QUICKLY
DIMINISH AS WINDS BACK AND INVERSION HEIGHTS FALL SUNDAY NIGHT. LOWS
SUNDAY NIGHT MAY OCCUR IN THE EVENING WITH TEMPERATURES STEADY OR
RISING OVERNIGHT. OTHERWISE...A WARMING TREND WILL BEGIN MONDAY AS
THE LONGWAVE TROF AMPLIFIES ALONG THE NORTH AMERICAN COAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1221 AM EST WED NOV 18 2015
STRONG LOW OVER IA WILL CONTINUE TO INTENSIFY AS IT LIFTS NNE INTO
WRN ONTARIO TODAY. STRONG SE WINDS ACROSS NRN INDIANA WILL VEER
TO SOUTH THIS MORNING AND SW THIS AFTN AS THE CDFNT ASSOCIATED
WITH THIS SYSTEM MOVES EAST ACROSS THE AREA ACCOMPANIED BY A BAND
OF RAIN WHICH SHOULD LOWER FLYING CONDITIONS TO MVFR. LIMITED
BOUNDARY LAYER MIXING IN THE WAA AHEAD OF THE FRONT SHOULD RESULT
A SGFNT LLWS THREAT CONTG THIS MORNING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING UNTIL 11 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
SYNOPSIS...JT
SHORT TERM...JT
LONG TERM...SKIPPER
AVIATION...JT
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1127 AM CST WED NOV 18 2015
.SYNOPSIS...
ISSUED AT 330 AM CST WED NOV 18 2015
WATER VAPOR IMAGERY SHOWS DEEP CLOSED LOW OVER EASTERN KS
WITH MOIST CONVEYOR FINALLY BEGINNING TO SHIFT EAST OF THE
MISSISSIPPI RIVER. AT THE SURFACE DEEPER LOW PRESSURE WAS
LOCATED OVER NORTHWEST IA WITH SECONDARY WEAK LOW OVER NORTHEAST
KS ATTENDANT TO NEAR STACKED SYSTEM. APPROACHING DRY SLOT AND
ATTENDANT UPPER LEVEL FORCING IS AIDING NARROW LINE OF SHOWERS
ARCING INTO EASTERN IA AND WEST CENTRAL IL ACCOMPANIED BY STRONG
WIND GUSTS OF 40 TO 55 MPH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CST WED NOV 18 2015
DEEP LOW OVER EASTERN KS WILL OPEN UP AND ACCELERATE NEWD TO
VICINITY OF LAKE SUPERIOR BY DAYS END IN RESPONSE TO UPSTREAM
SHORTWAVE TROUGH MOVING THROUGH THE NORTHERN ROCKIES. THE
INTERACTION/PHASING WILL RESULT IN MORE PRONOUNCED LONGWAVE
TROUGH OVER THE MIDWEST BY THURSDAY RESULTING IN MUCH COOLER
CONDITIONS.
TODAY... ARCING BAND OF SHOWERS WILL EXIT EASTERN IA AND
NORTHWEST IL NEXT 1-2+ HOURS... AND CONTINUE TO BE FOLLOWED BY
SOME DECREASE IN CLOUDS WITH DRY SLOT. HOWEVER... AS THE LOW
TRACKS NORTHEAST WILL SEE LOWER CLOUDS WRAP BACK AROUND INTO THE
AREA TODAY ALONG WITH SOME SHOWERS WITH SPOKES OF ENERGY ROTATING
AROUND THE LOW...WITH THE BETTER COVERAGE ANTICIPATED OVER
NORTHWEST 1/2 TO POSSIBLY 2/3RDS OF CWA. HIGHS FOR THE DAY HAVE
ALREADY OCCURRED MOST AREAS AND WILL JUST BE STEADY DROP ON TEMPS
THROUGH MIDDAY WITH COLD ADVECTION BEFORE TEMPS LEVEL OFF THIS
AFTERNOON MAINLY IN THE UPPER 40S TO LOWER 50S. EXPECT BRISK TO
WINDY CONDITIONS REDEVELOPING BY LATER THIS AM THROUGH AFTERNOON
WITH MIXING WITH RAP AND NAM SOUNDINGS SHOWING POTENTIAL TO TICKLE
WIND ADVISORY CRITERIA AT TIMES WITH ROUGHLY 30-35 KTS SHOWN
THROUGH THE MIXED LAYER AND 40-45+ KTS SITTING ATOP THE MIXED
LAYER. JUST HOW DEEP WE MIX WILL BE UNCERTAIN DUE TO CLOUD
COVER/TRENDS ... AND THUS REASON FOR NOT GOING WITH ADVISORY
ATTIM.
TONIGHT... SOME SHOWERS MAINLY NORTHERN CWA TO TAPER OFF BY
LATE EVE WITH INCOMING SUBSIDENCE LEADING TO DECREASING CLOUDS IN
WAKE OF WEAKENING LOW. STILL BRISK AT TIMES WITH LINGERING
GRADIENT. COLDER WITH LOWS MAINLY IN THE LOWER TO MIDDLE 30S.
.LONG TERM...(THURSDAY THROUGH NEXT TUESDAY)
ISSUED AT 330 AM CST WED NOV 18 2015
THURSDAY...TIGHT CYCLONIC LLVL FLOW SOUTH OF NORTHWESTERN GRT LKS
LONG WAVE TROF CENTER WILL MAKE FOR ANOTHER WINDY DAY THU WITH
SUSTAINED WEST TO NORTHWEST SFC WINDS OF 20 TO 30 MPH...AND GUSTS TO
45 MPH...NEAR ADVISORY LEVELS AGAIN. HIGH TEMPS IN THE 40S DESPITE
SUNSHINE AND DEEP MIXING. IF SFC WINDS CAN DECOUPLE ENOUGH ALONG
WITH CLEAR SKIES UNDER PASSING RIDGE LOBE...LOW TEMPS BY EARLY FRI
MORNING TO BE DOWN IN THE 20S ACRS MUCH OF THE LOCAL FCST AREA.
FRIDAY AND SATURDAY...ALL EYES TURN TO A POTENTIAL LATE FALL SNOW
SYSTEM THIS PERIOD...AS A WAVE CURRENTLY ACRS THE GULF OF AK DIGS
DOWN IN FRESHLY ESTABLISHED COLD CORE L/W TROF ACRS THE MID CONUS.
STILL MUCH UNCERTAINTY WITH THIS SYSTEM AND IT STILL BEING OFF
SHORE AND NOT REALLY SAMPLED BY LATEST MODEL INPUT DATA YET...MUCH
WILL DEPEND ON WHERE THE PRIME LLVL BAROCLINICITY LAYS OUT GENERALLY
FROM WEST-TO-EAST AND MID/UPPER JET PROPAGATION PATH OCCURS. LATEST
SUITE OF 00Z RUNS INDICATE MODELS STILL HAVING TROUBLE WITH THIS
HANDLING WITH LARGE VARIANCES FROM EACH OTHER IN TIMING...STRENGTH
AND HOW FAR NORTH OR SOUTH THE LOW GENERATING THE SNOW OCCURS. THE
00Z NAM IS THE FARTHEST TO THE NORTH BUT TRANSITIONS LLVL THERMAL
PARAMETERS COOLER FOR MAINLY SNOW IN A TYPE OF ADVECTION WING MOVING
IN ACRS MUCH OF THE CWA DURING FRI AFTERNOON...CONTINUING WELL INTO
THE EVENING BEFORE SHIFTING TO THE EAST. IT/S MAIN DEF ZONE OF SNOW
OCCURS JUST TO THE NORTH OF THE DVN CWA LATER FRI NIGHT INTO EARLY
SAT MORNING. THE 00Z GFS IS THE FURTHEST TO THE SOUTH...MOST PROGRESSIVE
BUT HAS ENOUGH PRE-WAVE WAA FOR RAIN OR A MIX SOUTH OF I80...BUT
TRANSITIONS TO ALL SNOW NORTH OF I80 WITH SEVERAL INCHES OF SNOW
ACCUM BY 00Z SAT. IT/S SNOW ALGORITHM THEN PRODUCES A SWATH OF 4-8
INCHES ALONG AND NORTH OF I80 BY SAT MORNING WHEN THE SYSTEM MAKES
IT/S WAY OFF TO THE EAST. JUST A FEW INCHES SOUTH OF I80 BY SAT AM.
THE 00Z ECMWF SURPRISINGLY COMES IN STRONGER/SLOWER WITH DEEPENING
THE LLVL CYCLONE ACRS THE SOUTHERN CWA LATER FRI NIGHT AND ROLLS IT
UP ACRS SOUTHERN LK MI BY 18Z SAT. WITH IT/S COLD PROFILES FOR
MAINLY ALL SNOW WITH THE PRECIP EVENT...IT/S SNOW ALGORITHM PRODUCES
4-7+ INCHES WITH IT/S DEF ZONE BY SAT MORNING ACRS THE NORTHERN HALF
OF THE DVN CWA...BIGGER TOTALS ACRS SOUTHERN WI. STRONG IN-WRAPPING
WINDS OF THE DEEPER ECMWF COULD ALSO MAKE FOR NEAR BLIZZARD
CONDITIONS IN NORTHERN PORTIONS OF THE DVN CWA LATE FRI NIGHT-SAT
MORNING.
FOR NOW WITH LOW CONFIDENCE AND THE SYSTEM STILL OFF SHORE...WILL
ADVERTISE A BIT OF A MIX IN THE SOUTH WITH A TRANSITION TO ALL SNOW
CWA-WIDE FRI NIGHT INTO SAT MORNING. SOME CONCERN HOW MUCH MOISTURE
DRAW FROM THE SOUTH THIS SYSTEM WILL HAVE AS WELL TO PRODUCE SUCH
BIG SNOW TOTALS...BUT IF TENDS CONTINUE THE CWA WILL LOOK TO BE IN
LINE FOR AT LEAST A WINTER WEATHER ADVISORY SNOW EVENT WITH A CHANCE
FOR WARNING CRITERIA TO BE MET IN OR NEAR THE FCST AREA. WITH ANY
KIND OF SNOW COVER...THE EXTENT OF COLD AIR SEEPING DOWN INTO THE
TROF BASE FOR THE REST OF THE WEEKEND WOULD MAKE FOR HIGHS SAT ONLY
IN THE UPPER 20S IN THE NORTH...TO MID-UPPER 30S IN THE SOUTH. WIND
DROP OFF UNDER CLEAR SKIES SAT NIGHT WOULD MAKE FOR SEASONABLY COLD
LOWS WELL DOWN INTO THE TEENS...AND SOME SNOW COVER OF AT LEAST 2-4
INCHES WOULD MAKE FOR SOME UPPER SINGLE DIGITS POSSIBLE IN THE NORTH
BY SUNDAY MORNING. HIGHS HAVING TROUBLE RECOVERING MUCH OUT OF THE
MID 30S ON SUNDAY.
SUNDAY THROUGH NEXT TUESDAY...LATEST MEDIUM RANGE MODEL TRENDS
CONTINUE TO SUGGEST THIS PERIOD TO BE MAINLY DRY WITH A TEMP
MODERATION INTO TUESDAY AS THE COLD POOL SHIFTS EAST ACRS THE GRT
LKS AND RETURN FLOW STRENGTHENS UP THE MS RVR VALLEY UNDER RE-
ESTABLISHING BROAD UPPER RIDGING ACRS THE CONUS. HIGH TEMPS TO
RECOVER BACK TO NORMAL LEVELS OR EVEN SLIGHTLY ABOVE NORMAL BY TUE
UNDER SUCH A SYNOPTIC REGIME CHANGE. ..12..
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1125 AM CST WED NOV 18 2015
WINDY WEATHER WILL DOMINATE THE TAF CYCLE ONCE AGAIN...AS SOUTH
WINDS OF 20 TO 30 KTS SWITCH TO WEST THROUGH THE PERIOD. THIS
TRANSITION WILL INCLUDE A SOMEWHAT LESS WINDY OVERNIGHT...BUT NO
LOWER THAN 12 KTS GUSTING TO THE LOWER 20 KT RANGE.
OTHERWISE...MVFR CIGS WILL SWEEP EAST SLOWLY THIS AFTERNOON OVER
ALL OF IOWA AND NORTHWEST ILLINOIS. BY MID EVENING...THE DRY AIR
MOVING IN ALOFT SHOULD ALLOW THE CLOUDS TO DISSIPATE WITH VFR
WEATHER LASTING FROM MID TO LATE EVENING THROUGH THURSDAY
AFTERNOON.
ERVIN
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...05
SHORT TERM...05
LONG TERM...12
AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
554 AM CST WED NOV 18 2015
.SYNOPSIS...
ISSUED AT 330 AM CST WED NOV 18 2015
WATER VAPOR IMAGERY SHOWS DEEP CLOSED LOW OVER EASTERN KS
WITH MOIST CONVEYOR FINALLY BEGINNING TO SHIFT EAST OF THE
MISSISSIPPI RIVER. AT THE SURFACE DEEPER LOW PRESSURE WAS
LOCATED OVER NORTHWEST IA WITH SECONDARY WEAK LOW OVER NORTHEAST
KS ATTENDANT TO NEAR STACKED SYSTEM. APPROACHING DRY SLOT AND
ATTENDANT UPPER LEVEL FORCING IS AIDING NARROW LINE OF SHOWERS
ARCING INTO EASTERN IA AND WEST CENTRAL IL ACCOMPANIED BY STRONG
WIND GUSTS OF 40 TO 55 MPH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CST WED NOV 18 2015
DEEP LOW OVER EASTERN KS WILL OPEN UP AND ACCELERATE NEWD TO
VICINITY OF LAKE SUPERIOR BY DAYS END IN RESPONSE TO UPSTREAM
SHORTWAVE TROUGH MOVING THROUGH THE NORTHERN ROCKIES. THE
INTERACTION/PHASING WILL RESULT IN MORE PRONOUNCED LONGWAVE
TROUGH OVER THE MIDWEST BY THURSDAY RESULTING IN MUCH COOLER
CONDITIONS.
TODAY... ARCING BAND OF SHOWERS WILL EXIT EASTERN IA AND
NORTHWEST IL NEXT 1-2+ HOURS... AND CONTINUE TO BE FOLLOWED BY
SOME DECREASE IN CLOUDS WITH DRY SLOT. HOWEVER... AS THE LOW
TRACKS NORTHEAST WILL SEE LOWER CLOUDS WRAP BACK AROUND INTO THE
AREA TODAY ALONG WITH SOME SHOWERS WITH SPOKES OF ENERGY ROTATING
AROUND THE LOW...WITH THE BETTER COVERAGE ANTICIPATED OVER
NORTHWEST 1/2 TO POSSIBLY 2/3RDS OF CWA. HIGHS FOR THE DAY HAVE
ALREADY OCCURRED MOST AREAS AND WILL JUST BE STEADY DROP ON TEMPS
THROUGH MIDDAY WITH COLD ADVECTION BEFORE TEMPS LEVEL OFF THIS
AFTERNOON MAINLY IN THE UPPER 40S TO LOWER 50S. EXPECT BRISK TO
WINDY CONDITIONS REDEVELOPING BY LATER THIS AM THROUGH AFTERNOON
WITH MIXING WITH RAP AND NAM SOUNDINGS SHOWING POTENTIAL TO TICKLE
WIND ADVISORY CRITERIA AT TIMES WITH ROUGHLY 30-35 KTS SHOWN
THROUGH THE MIXED LAYER AND 40-45+ KTS SITTING ATOP THE MIXED
LAYER. JUST HOW DEEP WE MIX WILL BE UNCERTAIN DUE TO CLOUD
COVER/TRENDS ... AND THUS REASON FOR NOT GOING WITH ADVISORY
ATTIM.
TONIGHT... SOME SHOWERS MAINLY NORTHERN CWA TO TAPER OFF BY
LATE EVE WITH INCOMING SUBSIDENCE LEADING TO DECREASING CLOUDS IN
WAKE OF WEAKENING LOW. STILL BRISK AT TIMES WITH LINGERING
GRADIENT. COLDER WITH LOWS MAINLY IN THE LOWER TO MIDDLE 30S.
.LONG TERM...(THURSDAY THROUGH NEXT TUESDAY)
ISSUED AT 330 AM CST WED NOV 18 2015
THURSDAY...TIGHT CYCLONIC LLVL FLOW SOUTH OF NORTHWESTERN GRT LKS
LONG WAVE TROF CENTER WILL MAKE FOR ANOTHER WINDY DAY THU WITH
SUSTAINED WEST TO NORTHWEST SFC WINDS OF 20 TO 30 MPH...AND GUSTS TO
45 MPH...NEAR ADVISORY LEVELS AGAIN. HIGH TEMPS IN THE 40S DESPITE
SUNSHINE AND DEEP MIXING. IF SFC WINDS CAN DECOUPLE ENOUGH ALONG
WITH CLEAR SKIES UNDER PASSING RIDGE LOBE...LOW TEMPS BY EARLY FRI
MORNING TO BE DOWN IN THE 20S ACRS MUCH OF THE LOCAL FCST AREA.
FRIDAY AND SATURDAY...ALL EYES TURN TO A POTENTIAL LATE FALL SNOW
SYSTEM THIS PERIOD...AS A WAVE CURRENTLY ACRS THE GULF OF AK DIGS
DOWN IN FRESHLY ESTABLISHED COLD CORE L/W TROF ACRS THE MID CONUS.
STILL MUCH UNCERTAINTY WITH THIS SYSTEM AND IT STILL BEING OFF
SHORE AND NOT REALLY SAMPLED BY LATEST MODEL INPUT DATA YET...MUCH
WILL DEPEND ON WHERE THE PRIME LLVL BAROCLINICITY LAYS OUT GENERALLY
FROM WEST-TO-EAST AND MID/UPPER JET PROPAGATION PATH OCCURS. LATEST
SUITE OF 00Z RUNS INDICATE MODELS STILL HAVING TROUBLE WITH THIS
HANDLING WITH LARGE VARIANCES FROM EACH OTHER IN TIMING...STRENGTH
AND HOW FAR NORTH OR SOUTH THE LOW GENERATING THE SNOW OCCURS. THE
00Z NAM IS THE FARTHEST TO THE NORTH BUT TRANSITIONS LLVL THERMAL
PARAMETERS COOLER FOR MAINLY SNOW IN A TYPE OF ADVECTION WING MOVING
IN ACRS MUCH OF THE CWA DURING FRI AFTERNOON...CONTINUING WELL INTO
THE EVENING BEFORE SHIFTING TO THE EAST. IT/S MAIN DEF ZONE OF SNOW
OCCURS JUST TO THE NORTH OF THE DVN CWA LATER FRI NIGHT INTO EARLY
SAT MORNING. THE 00Z GFS IS THE FURTHEST TO THE SOUTH...MOST PROGRESSIVE
BUT HAS ENOUGH PRE-WAVE WAA FOR RAIN OR A MIX SOUTH OF I80...BUT
TRANSITIONS TO ALL SNOW NORTH OF I80 WITH SEVERAL INCHES OF SNOW
ACCUM BY 00Z SAT. IT/S SNOW ALGORITHM THEN PRODUCES A SWATH OF 4-8
INCHES ALONG AND NORTH OF I80 BY SAT MORNING WHEN THE SYSTEM MAKES
IT/S WAY OFF TO THE EAST. JUST A FEW INCHES SOUTH OF I80 BY SAT AM.
THE 00Z ECMWF SURPRISINGLY COMES IN STRONGER/SLOWER WITH DEEPENING
THE LLVL CYCLONE ACRS THE SOUTHERN CWA LATER FRI NIGHT AND ROLLS IT
UP ACRS SOUTHERN LK MI BY 18Z SAT. WITH IT/S COLD PROFILES FOR
MAINLY ALL SNOW WITH THE PRECIP EVENT...IT/S SNOW ALGORITHM PRODUCES
4-7+ INCHES WITH IT/S DEF ZONE BY SAT MORNING ACRS THE NORTHERN HALF
OF THE DVN CWA...BIGGER TOTALS ACRS SOUTHERN WI. STRONG IN-WRAPPING
WINDS OF THE DEEPER ECMWF COULD ALSO MAKE FOR NEAR BLIZZARD
CONDITIONS IN NORTHERN PORTIONS OF THE DVN CWA LATE FRI NIGHT-SAT
MORNING.
FOR NOW WITH LOW CONFIDENCE AND THE SYSTEM STILL OFF SHORE...WILL
ADVERTISE A BIT OF A MIX IN THE SOUTH WITH A TRANSITION TO ALL SNOW
CWA-WIDE FRI NIGHT INTO SAT MORNING. SOME CONCERN HOW MUCH MOISTURE
DRAW FROM THE SOUTH THIS SYSTEM WILL HAVE AS WELL TO PRODUCE SUCH
BIG SNOW TOTALS...BUT IF TENDS CONTINUE THE CWA WILL LOOK TO BE IN
LINE FOR AT LEAST A WINTER WEATHER ADVISORY SNOW EVENT WITH A CHANCE
FOR WARNING CRITERIA TO BE MET IN OR NEAR THE FCST AREA. WITH ANY
KIND OF SNOW COVER...THE EXTENT OF COLD AIR SEEPING DOWN INTO THE
TROF BASE FOR THE REST OF THE WEEKEND WOULD MAKE FOR HIGHS SAT ONLY
IN THE UPPER 20S IN THE NORTH...TO MID-UPPER 30S IN THE SOUTH. WIND
DROP OFF UNDER CLEAR SKIES SAT NIGHT WOULD MAKE FOR SEASONABLY COLD
LOWS WELL DOWN INTO THE TEENS...AND SOME SNOW COVER OF AT LEAST 2-4
INCHES WOULD MAKE FOR SOME UPPER SINGLE DIGITS POSSIBLE IN THE NORTH
BY SUNDAY MORNING. HIGHS HAVING TROUBLE RECOVERING MUCH OUT OF THE
MID 30S ON SUNDAY.
SUNDAY THROUGH NEXT TUESDAY...LATEST MEDIUM RANGE MODEL TRENDS
CONTINUE TO SUGGEST THIS PERIOD TO BE MAINLY DRY WITH A TEMP
MODERATION INTO TUESDAY AS THE COLD POOL SHIFTS EAST ACRS THE GRT
LKS AND RETURN FLOW STRENGTHENS UP THE MS RVR VALLEY UNDER RE-
ESTABLISHING BROAD UPPER RIDGING ACRS THE CONUS. HIGH TEMPS TO
RECOVER BACK TO NORMAL LEVELS OR EVEN SLIGHTLY ABOVE NORMAL BY TUE
UNDER SUCH A SYNOPTIC REGIME CHANGE. ..12..
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 548 AM CST WED NOV 18 2015
WINDS WILL BECOME GUSTY BY MID AM AT 15-30 KTS AND REMAIN SO
THROUGH THE REST OF THE TAF CYCLE WITH TIGHT PRESSURE GRADIENT.
CIGS WILL GENERALLY LOWER INTO LOWER END VFR TO MVFR RANGE
TODAY WITH A FEW SPOKES OF LIGHTER SHOWERS ROTATING ACROSS
AREA AROUND A WEAKENING UPPER LEVEL STORM SYSTEM. TONIGHT WILL
SEE DECREASING CLOUDS AND RETURN TO VFR CONDITIONS BY LATE
EVENING INTO THE EARLY OVERNIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...05
SHORT TERM...05
LONG TERM...12
AVIATION...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
406 AM CST WED NOV 18 2015
.SYNOPSIS...
ISSUED AT 330 AM CST WED NOV 18 2015
WATER VAPOR IMAGERY SHOWS DEEP CLOSED LOW OVER EASTERN KS
WITH MOIST CONVEYOR FINALLY BEGINNING TO SHIFT EAST OF THE
MISSISSIPPI RIVER. AT THE SURFACE DEEPER LOW PRESSURE WAS
LOCATED OVER NORTHWEST IA WITH SECONDARY WEAK LOW OVER NORTHEAST
KS ATTENDANT TO NEAR STACKED SYSTEM. APPROACHING DRY SLOT AND
ATTENDANT UPPER LEVEL FORCING IS AIDING NARROW LINE OF SHOWERS
ARCING INTO EASTERN IA AND WEST CENTRAL IL ACCOMPANIED BY STRONG
WIND GUSTS OF 40 TO 55 MPH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CST WED NOV 18 2015
DEEP LOW OVER EASTERN KS WILL OPEN UP AND ACCELERATE NEWD TO
VICINITY OF LAKE SUPERIOR BY DAYS END IN RESPONSE TO UPSTREAM
SHORTWAVE TROUGH MOVING THROUGH THE NORTHERN ROCKIES. THE
INTERACTION/PHASING WILL RESULT IN MORE PRONOUNCED LONGWAVE
TROUGH OVER THE MIDWEST BY THURSDAY RESULTING IN MUCH COOLER
CONDITIONS.
TODAY... ARCING BAND OF SHOWERS WILL EXIT EASTERN IA AND
NORTHWEST IL NEXT 1-2+ HOURS... AND CONTINUE TO BE FOLLOWED BY
SOME DECREASE IN CLOUDS WITH DRY SLOT. HOWEVER... AS THE LOW
TRACKS NORTHEAST WILL SEE LOWER CLOUDS WRAP BACK AROUND INTO THE
AREA TODAY ALONG WITH SOME SHOWERS WITH SPOKES OF ENERGY ROTATING
AROUND THE LOW...WITH THE BETTER COVERAGE ANTICIPATED OVER
NORTHWEST 1/2 TO POSSIBLY 2/3RDS OF CWA. HIGHS FOR THE DAY HAVE
ALREADY OCCURRED MOST AREAS AND WILL JUST BE STEADY DROP ON TEMPS
THROUGH MIDDAY WITH COLD ADVECTION BEFORE TEMPS LEVEL OFF THIS
AFTERNOON MAINLY IN THE UPPER 40S TO LOWER 50S. EXPECT BRISK TO
WINDY CONDITIONS REDEVELOPING BY LATER THIS AM THROUGH AFTERNOON
WITH MIXING WITH RAP AND NAM SOUNDINGS SHOWING POTENTIAL TO TICKLE
WIND ADVISORY CRITERIA AT TIMES WITH ROUGHLY 30-35 KTS SHOWN
THROUGH THE MIXED LAYER AND 40-45+ KTS SITTING ATOP THE MIXED
LAYER. JUST HOW DEEP WE MIX WILL BE UNCERTAIN DUE TO CLOUD
COVER/TRENDS ... AND THUS REASON FOR NOT GOING WITH ADVISORY
ATTIM.
TONIGHT... SOME SHOWERS MAINLY NORTHERN CWA TO TAPER OFF BY
LATE EVE WITH INCOMING SUBSIDENCE LEADING TO DECREASING CLOUDS IN
WAKE OF WEAKENING LOW. STILL BRISK AT TIMES WITH LINGERING
GRADIENT. COLDER WITH LOWS MAINLY IN THE LOWER TO MIDDLE 30S.
.LONG TERM...(THURSDAY THROUGH NEXT TUESDAY)
ISSUED AT 330 AM CST WED NOV 18 2015
THURSDAY...TIGHT CYCLONIC LLVL FLOW SOUTH OF NORTHWESTERN GRT LKS
LONG WAVE TROF CENTER WILL MAKE FOR ANOTHER WINDY DAY THU WITH
SUSTAINED WEST TO NORTHWEST SFC WINDS OF 20 TO 30 MPH...AND GUSTS TO
45 MPH...NEAR ADVISORY LEVELS AGAIN. HIGH TEMPS IN THE 40S DESPITE
SUNSHINE AND DEEP MIXING. IF SFC WINDS CAN DECOUPLE ENOUGH ALONG
WITH CLEAR SKIES UNDER PASSING RIDGE LOBE...LOW TEMPS BY EARLY FRI
MORNING TO BE DOWN IN THE 20S ACRS MUCH OF THE LOCAL FCST AREA.
FRIDAY AND SATURDAY...ALL EYES TURN TO A POTENTIAL LATE FALL SNOW
SYSTEM THIS PERIOD...AS A WAVE CURRENTLY ACRS THE GULF OF AK DIGS
DOWN IN FRESHLY ESTABLISHED COLD CORE L/W TROF ACRS THE MID CONUS.
STILL MUCH UNCERTAINTY WITH THIS SYSTEM AND IT STILL BEING OFF
SHORE AND NOT REALLY SAMPLED BY LATEST MODEL INPUT DATA YET...MUCH
WILL DEPEND ON WHERE THE PRIME LLVL BAROCLINICITY LAYS OUT GENERALLY
FROM WEST-TO-EAST AND MID/UPPER JET PROPAGATION PATH OCCURS. LATEST
SUITE OF 00Z RUNS INDICATE MODELS STILL HAVING TROUBLE WITH THIS
HANDLING WITH LARGE VARIANCES FROM EACH OTHER IN TIMING...STRENGTH
AND HOW FAR NORTH OR SOUTH THE LOW GENERATING THE SNOW OCCURS. THE
00Z NAM IS THE FARTHEST TO THE NORTH BUT TRANSITIONS LLVL THERMAL
PARAMETERS COOLER FOR MAINLY SNOW IN A TYPE OF ADVECTION WING MOVING
IN ACRS MUCH OF THE CWA DURING FRI AFTERNOON...CONTINUING WELL INTO
THE EVENING BEFORE SHIFTING TO THE EAST. IT/S MAIN DEF ZONE OF SNOW
OCCURS JUST TO THE NORTH OF THE DVN CWA LATER FRI NIGHT INTO EARLY
SAT MORNING. THE 00Z GFS IS THE FURTHEST TO THE SOUTH...MOST PROGRESSIVE
BUT HAS ENOUGH PRE-WAVE WAA FOR RAIN OR A MIX SOUTH OF I80...BUT
TRANSITIONS TO ALL SNOW NORTH OF I80 WITH SEVERAL INCHES OF SNOW
ACCUM BY 00Z SAT. IT/S SNOW ALGORITHM THEN PRODUCES A SWATH OF 4-8
INCHES ALONG AND NORTH OF I80 BY SAT MORNING WHEN THE SYSTEM MAKES
IT/S WAY OFF TO THE EAST. JUST A FEW INCHES SOUTH OF I80 BY SAT AM.
THE 00Z ECMWF SURPRISINGLY COMES IN STRONGER/SLOWER WITH DEEPENING
THE LLVL CYCLONE ACRS THE SOUTHERN CWA LATER FRI NIGHT AND ROLLS IT
UP ACRS SOUTHERN LK MI BY 18Z SAT. WITH IT/S COLD PROFILES FOR
MAINLY ALL SNOW WITH THE PRECIP EVENT...IT/S SNOW ALGORITHM PRODUCES
4-7+ INCHES WITH IT/S DEF ZONE BY SAT MORNING ACRS THE NORTHERN HALF
OF THE DVN CWA...BIGGER TOTALS ACRS SOUTHERN WI. STRONG IN-WRAPPING
WINDS OF THE DEEPER ECMWF COULD ALSO MAKE FOR NEAR BLIZZARD
CONDITIONS IN NORTHERN PORTIONS OF THE DVN CWA LATE FRI NIGHT-SAT
MORNING.
FOR NOW WITH LOW CONFIDENCE AND THE SYSTEM STILL OFF SHORE...WILL
ADVERTISE A BIT OF A MIX IN THE SOUTH WITH A TRANSITION TO ALL SNOW
CWA-WIDE FRI NIGHT INTO SAT MORNING. SOME CONCERN HOW MUCH MOISTURE
DRAW FROM THE SOUTH THIS SYSTEM WILL HAVE AS WELL TO PRODUCE SUCH
BIG SNOW TOTALS...BUT IF TENDS CONTINUE THE CWA WILL LOOK TO BE IN
LINE FOR AT LEAST A WINTER WEATHER ADVISORY SNOW EVENT WITH A CHANCE
FOR WARNING CRITERIA TO BE MET IN OR NEAR THE FCST AREA. WITH ANY
KIND OF SNOW COVER...THE EXTENT OF COLD AIR SEEPING DOWN INTO THE
TROF BASE FOR THE REST OF THE WEEKEND WOULD MAKE FOR HIGHS SAT ONLY
IN THE UPPER 20S IN THE NORTH...TO MID-UPPER 30S IN THE SOUTH. WIND
DROP OFF UNDER CLEAR SKIES SAT NIGHT WOULD MAKE FOR SEASONABLY COLD
LOWS WELL DOWN INTO THE TEENS...AND SOME SNOW COVER OF AT LEAST 2-4
INCHES WOULD MAKE FOR SOME UPPER SINGLE DIGITS POSSIBLE IN THE NORTH
BY SUNDAY MORNING. HIGHS HAVING TROUBLE RECOVERING MUCH OUT OF THE
MID 30S ON SUNDAY.
SUNDAY THROUGH NEXT TUESDAY...LATEST MEDIUM RANGE MODEL TRENDS
CONTINUE TO SUGGEST THIS PERIOD TO BE MAINLY DRY WITH A TEMP
MODERATION INTO TUESDAY AS THE COLD POOL SHIFTS EAST ACRS THE GRT
LKS AND RETURN FLOW STRENGTHENS UP THE MS RVR VALLEY UNDER RE-
ESTABLISHING BROAD UPPER RIDGING ACRS THE CONUS. HIGH TEMPS TO
RECOVER BACK TO NORMAL LEVELS OR EVEN SLIGHTLY ABOVE NORMAL BY TUE
UNDER SUCH A SYNOPTIC REGIME CHANGE. ..12..
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1131 PM CST TUE NOV 17 2015
A DEEP LOW PRESSURE SYSTEM WILL KEEP WINDS GUSTY AT ALL THE TERMINALS
THE NEXT 24 HOURS OF 15 TO 25 KTS. WINDS WILL BE FROM THE SOUTHEAST
OVERNIGHT...SHIFTING TO THE SOUTHWEST WEDNESDAY MORNING WITH GUSTS
OVER 30 KTS POSSIBLE. CLOUDS WILL RANGE FROM 2 TO 5K AGL OR LOWER
END VFR TO HIGHER END MVFR FLYING CONDITIONS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...05
SHORT TERM...05
LONG TERM...12
AVIATION...NICHOLS
AREA FORECAST DISCUSSION
NWS JACKSON KY
102 PM EST WED NOV 18 2015
.UPDATE...
ISSUED AT 1245 PM EST WED NOV 18 2015
RAIN SHOWERS ARE FINALLY STARTING TO INCH THEIR WAY INTO THE FAR
SOUTHWESTERN COUNTIES. THIS IS A SLIGHTLY SLOWER PROGRESSION THAN
WAS ORIGINALLY FORECASTED. AS SUCH...TRIED TO PUSH BACK TIMING OF
PRECIP ONSET BY AN HOUR TO TWO HOURS FOR THE REMAINDER OF THE
AFTERNOON. WINDS HAVE SHOWN AN INCREASING TREND OVER THE LAST
COUPLE OF HOURS AS WELL...WITH SUSTAINED WINDS NOW BETWEEN 10 AND
15 KNOTS ACROSS MUCH OF THE CWA...AND GUSTS BETWEEN 15 AND 30KTS.
LOADED IN THE LATEST TEMPS...DEW POINT...AND WIND OBSERVATION INTO
THE NEAR TERM GRIDS TO MAKE SURE THE FORECAST REFLECTED THE
CURRENT CONDITIONS. ALL GRIDS HAVE BEEN SAVED AND SENT TO THE
WEB/NDFD...THOUGH CHANGES ARE NOT SIGNIFICANT ENOUGH TO REQUIRE A
NEW FORECAST PACKAGE AT THIS TIME.
UPDATE ISSUED AT 650 AM EST WED NOV 18 2015
THE BIG STORY WILL BE THE RAIN SHOWERS MOVING EAST INTO EASTERN KY
THIS AFTERNOON. DID MAKE SOME MINOR ADJUSTMENTS TO THE GRIDS IN
TERMS OF POPS TO SLOW DOWN SLIGHTLY GIVEN SOME OF THE MESO
MODELS...BUT OVERALL TIMING LOOKS ON TRACK. DID SOME MINOR TWEAKS
TO TEMPS/DEWS/WINDS TO LINE UP BETTER TO LATEST OBS AND TRENDS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 348 AM EST WED NOV 18 2015
THIS MORNING STRONG CLOSED LOW IS WELL ESTABLISHED ACROSS THE
CENTRAL PLAINS...WITH 00Z ANALYSIS ACROSS THE PLAINS SHOWING A
537MB HEIGHT WHICH IS ACTUALLY MIN FOR THIS DAY BASED ON SOUNDING
CLIMO. THIS JUST SPEAKS TO THE STRENGTH OF THIS POTENT
SYSTEM...WHICH WILL SWING A COLD FRONT ACROSS OUT AREA TODAY. THIS
LOW IS PROGGED PHASE WITH BROADER UPPER LOW ACROSS CANADA AND
OVERALL BROAD TROUGHING SETS UP ACROSS THE CENTRAL U.S. TO MID
ATLANTIC. WHILE RIDGING HOLD ON A BIT ACROSS THE NORTHEAST U.S.
INTO THE CANADIAN MARITIMES. WHILE THIS SYSTEM WILL USHER IN
COOLER AIR...THE COLDEST AIR WILL STAY LOCKED UP ACROSS THE
NORTHERN PLAINS TO THE WESTERN GREAT LAKES.
NOW THE DEEPER SURFACE LOW WILL TRACK NNE INTO THE UPPER
MIDWEST...WHILE ATTENDANT OCCLUDED FRONT AND TRIPLE POINT TRACK
EAST. THIS WILL BE OUR WEATHER MAKER TODAY BRINGING STRONG WINDS
AND WIDESPREAD RAIN SHOWERS ACROSS THE REGION TODAY. LETS TALK
WIND FIRST AS PRESSURE GRADIENT CONTINUES TO BECOME EVIDENT THIS
MORNING IN THE BATTLE GROUND BETWEEN THE DEEP LOW AND STRONG
SURFACE HIGH TO THE NORTHEAST. THIS WILL COUPLE WITH STRONG JET
ENERGY ALOFT WITH FORECAST SOUNDINGS AND PLAIN VIEW WINDS AT 850MB
INDICATING 70KT PLUS CORE RUNNING ACROSS THE REGION AS WE MOVE
TOWARD THE AFTERNOON. WE ARE ALREADY SEEING 30 TO 45 MPH GUST OF
BLACK MOUNTAIN THIS MORNING AND WHILE MIXING HEIGHTS WILL NOT BE
HIGH...AT OR BELOW 1000 FT IN GENERAL...IT WILL NOT TAKE MUCH
HEIGHT TO MIX DOWN SOME GUSTY WINDS. ALL THIS SAID THINK WE ARE IN
GOOD SHAPE WITH OVERALL TIMING OF HEADLINES AT THIS POINT.
NOW LETS DISCUSS THE PRECIP FOR THE EVENT WHICH WILL BE THE MOST
WE HAVE SEEN IN AT LEAST A MONTH NOW AND AT LEAST DOUBLE OUR
MONTHLY TOTAL SO FAR FOR NOV. THIS BAND OF MODERATE TO HEAVY RAIN
SHOWERS IS MAKING IT INTO FAR WESTERN KY THIS MORNING BASED ON
WSR-88D MOSAIC. AREAS IN FAR WEST ARE SEEING AROUND A INCH OF
PRECIP BASED ON MESONETS SINCE MIDNIGHT CST. NOW LOOKING AT RADAR
AND COMPARING SOME OF THE MESO MODELS THIS MORNING...THE ARW-NMM
SEEMS TO HAVE THE OVERALL BEST HANDLE ON TIMING. THE HRRR IS A BIT
SLOW BASED ON RADAR. THAT SAID OVERALL BEST CHANCES OF PRECIP WILL
BE THIS AFTERNOON AS STRONG LOW LEVEL JET SETS UP...NEARER THE
RIGHT ENTRANCE OF THE 300MB JET TO THE WEST...AND PWATS IN THE 1.4
OR HIGHER RANGE WHICH IS ABOVE NORMAL FOR BNA BASED ON SOUNDING
CLIMO. GIVEN THIS DID NOT CHANGE TOO MUCH WITH RESPECT TO TIMING
OF PRECIP...BUT PERHAPS A BIT SLOWER IN PROGRESSING IN OVERALL.
GENERALLY STUCK CLOSE TO THE CR BLEND FOR QPF...WHICH SEEMS TO
MATCH UP WELL OVERALL WITH THE NEIGHBORING OFFICES. THAT SAID
AMOUNTS ARE EXPECTED TO BE GENERALLY A INCH TO INCH AND A
QUARTER...BUT FAR SE COULD STILL SEE A BIT OF DOWNSLOPING WHICH
MAY HOLD THEM A BIT LOWER BUT NOT BY MUCH.
NOW FOR TONIGHT INTO THURSDAY FRONT SHOULD WORK OUT OF THE REGION
THROUGH THE EVENING AND GRADIENT/WINDS WILL WEAKEN. THE FORECAST
SOUNDINGS AND TIME HEIGHTS WOULD SUGGEST POSSIBLE STRATUS HANGING
TONIGHT OR PERHAPS FOG. RIGHT NOW WILL HOLD OFF ON LOWER CLOUDS
SINCE IT IS A BIT UNCERTAIN ON EXACTLY WHAT WILL OCCUR...WITH
CLEARING SKIES ARE QUICK BEHIND THIS FRONT DOWN STREAM. WHILE
WINDS WEAKEN WE SHOULD STAY SOME WHAT MIXED...BUT HIGH WILL BEGIN
NUDGING INTO THE REGION THROUGH THE DAY THURSDAY LEADING TO DRIER
CONDITIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 415 AM EST WED NOV 18 2015
A RATHER BROAD TROUGHING IS EXPECTED TO ENCOMPASS MUCH OF THE
CONUS FROM THE ROCKIES EAST INTO THE CENTRAL CONUS TO START THE
PERIOD WHILE A CLOSED UPPER LOW OVER WESTERN ONTARIO NORTH OF LAKE
SUPERIOR IS EXPECTED TO BE RETURNING NORTH. RIDGING AT THAT POINT
CENTERED NEAR CUBA AND THE BAHAMAS IS EXPECTED TO EXTEND NORTH
ACROSS PORTIONS OF THE WESTERN ATLANTIC. HOWEVER...THE 500 MB
TROUGH AXIS IS EXPECTED TO BE MOVE ACROSS THE COMMONWEALTH AND
LOWER OH VALLEY REGION AT THE START OF THE PERIOD WHILE HIGH
PRESSURE BUILDS IN AT THE SFC. BY FRIDAY THE BROAD TROUGH SHOULD
ENCOMPASS MUCH OF THE CONUS EAST OF THE ROCKIES.
A SHORTWAVE MOVING THROUGH THIS TROUGH IN THE NORTHERN STREAM
FROM THE ROCKIES AND SOUTHERN CANADA IS EXPECTED TO MOVE INTO THE
PLAINS...INTERACT WITH A SHORTWAVE ROTATING AROUND THE CANADIAN
UPPER LOW AND SHARPEN THE TROUGH OVER THE CENTRAL CONUS BY FRI
EVENING AND FRIDAY NIGHT. AT THAT POINT...SC HIGH PRESSURE WILL
BEGIN TO DEPART TO THE NORTHEAST HEIGHTS ACROSS EAST KY SHOULD
REMAIN NEARLY STEADY ON FRI ACROSS EAST KY. HEIGHTS SHOULD AGAIN
FALL AS THE NEXT SHORTWAVE TROUGH AND ASSOCIATED COLD FRONT
APPROACH THE LOWER OH VALLEY AND APPALACHIAN REGION FRI NIGHT AND
THEN MOVE ACROSS THE AREA SAT INTO SAT EVENING WITH LIMITED
MOISTURE. 850 MB TEMPS SHOULD DROP TO NEAR -9C OR -10C ON SAT
NIGHT AND THEN REMAIN NEAR THAT LEVEL INTO SUNDAY.
HEIGHT RISES ARE THEN EXPECTED AS THIS SYSTEM DEPARTS INTO AT
LEAST EARLY ON SUNDAY WITH SFC HIGH PRESSURE BUILDING TOWARD
EASTERN KY. HOWEVER...ONE MORE SHORTWAVE IS EXPECTED TO MOVE
ACROSS THE AREA TO END THE WEEKEND...BUT THERE ARE MODEL TIMING
DIFFERENCES WITH THIS AND MOISTURE SHOULD BE EVEN MORE LIMITED
THAN THE SHORTWAVE TROUGH ON SATURDAY SO NO MORE THAN MID AND HIGH
CLOUDS ARE ANTICIPATED. HEIGHTS SHOULD RISE AGAIN AT THE END OT
HE PERIOD...WITH SFC HIGH PRESSURE ARRIVE EARLY NEXT WEEK WITH SFC
AND UPPER LEVEL RIDGING DOMINATING. THE AIRMASS SHOULD ALSO
MODERATE WITH 85O MB TEMPS CLIMBING ABOVE 0C AND MAKING A RUN
TOWARD 5C BY THE END OF THE PERIOD.
TEMPERATURES SHOULD BE RATHER MILD IN THE 40S TO LOWER 50S AHEAD
OF THE SATURDAY TO SATURDAY EVENING COLD FRONT. TEMPERATURES WILL
DROP QUICKLY BEHIND THE FRONT...BUT DRIER AIR WILL ARRIVE QUICKLY
AS WELL. THERE IS A SMALL WINDOW ON SAT EVENING WHERE IF THE
MOISTURE LINGERED LONG ENOUGH AS THE COLUMN COOLS FOR A FEW FLAKES
TO MIX IN OR AN ISOLATED SNOW SHOWER OR TWO OR A FEW FLURRIES...
PARTICULARLY IN THE HIGHEST ELEVATIONS NEAR THE VA BORDER.
CONFIDENCE IN THIS REMAIN LOW HOWEVER...AS THE 0Z MODEL RUN
GENERALLY HAS THE LOW LEVELS DRYING OUT VERY QUICK...ECMWF...OR
PRESENCE OF ICE IN THE LOW CLOUDS PERHAPS ONLY FROM SEEDER FEEDER
IF THAT WERE TO OCCUR RIGHT AS THE MOISTURE DEPARTS. IF FLAKES DO
IN FACT OCCUR...NO ACCUMULATION IS EXPECTED.
TEMPERATURES ARE EXPECTED TO DROP WELL BELOW FREEZING SATURDAY
NIGHT...AS SKIES CLEAR AND BE EVEN COLDER SUNDAY NIGHT. BELOW
FREEZING TEMPERATURES FOR AT LEAST EASTERN VALLEYS ARE ALSO
EXPECTED ON MONDAY NIGHT. PENDING CLOUD COVER AND TIMING OF THE
SHORTWAVE TO MOVE ACROSS THE OHIO VALLEY...SOME TEENS WILL BE
POSSIBLE ON SUNDAY NIGHT AS SFC HIGH PRESSURE BUILDS IN. GFS
BASED COOP MOS GUIDANCE FOR MANY VALLEY LOCATIONS SUPPORTS TEENS
FOR SUN NIGHT WITH TEMPERATURES THERE WELL DOWN INTO THE 20S FOR
MON NIGHT AS WELL. TEMPERATURES WILL MODERATE ON MONDAY AND
TUESDAY...REACHING THE 40S MONDAY AND MID 40S TO LOWER 50S ON
TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1257 PM EST WED NOV 18 2015
A LINE OF RAIN SHOWERS ARE CURRENTLY MAKING THEIR WAY INTO
EASTERN KY...WITH AN ETA AT KSME WITHIN THE NEXT HOUR. TRIED TO
TIME OUT THE ONSET OF THE PRECIP ACROSS THE TAF SITES OF EASTERN
KY THROUGH THIS AFTERNOON. VIS AND CIGS WILL LIKELY FALL AS WE
START SEEING THE RAIN...WITH MVFR CONDITIONS EXPECTED THROUGHOUT
THE AFTERNOON...THOUGH SOME FLUCTUATION IN AND OUT OF THIS
CATEGORY IS MOST LIKELY. PERHAPS THE BIGGEST CONCERN DURING THE
TAF PERIOD WILL BE THE WINDS...PARTICULARLY ALOFT. SW WINDS
BETWEEN 10 AND 20 KT AT THE SURFACE AND GUSTS BETWEEN 25 AND 35
KNOTS WILL BE POSSIBLE THROUGHOUT THE AFTERNOON...WITH SOME
LOCATIONS POSSIBLY GUSTING HIGHER. WINDS WILL ONLY INCREASE AS YOU
HEAD HIGHER IN ALTITUDE. THE COLD FRONT IS EXPECTED TO PASS OVER
THIS EVENING...WITH RAIN EXPECTED TO QUICKLY COME TO AN END AFTER
THE FRONTAL PASSAGE. THIS WILL ALLOW VIS AND CIGS TO INCREASE TO
VFR...AND WINDS TO WANE AS THE PRESSURE GRADIENTS RELAX. CLEARING
AND CALM CONDITIONS ARE THEN EXPECTED DURING THE OVERNIGHT HOURS.
DEPENDING ON WINDS AND RAINFALL...FOG OR LOW STRATUS WILL
CERTAINLY BE POSSIBLE...BUT NOT CONFIDENT ON THIS AT THIS POINT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR KYZ044-050>052-
058>060-068-069-079-080-083>086-108-111-114-116.
WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ087-088-104-106-
107-109-110-112-113-115-117>120.
&&
$$
UPDATE...JMW
SHORT TERM...DJ
LONG TERM...JP
AVIATION...JMW
AREA FORECAST DISCUSSION
National Weather Service Paducah KY
1137 AM CST WED NOV 18 2015
.UPDATE...
Issued at 1137 AM CST WED NOV 18 2015
Updated for 18Z aviation forecast discussion.
&&
.SHORT TERM...(Today through Friday)
Issued at 231 AM CST WED NOV 18 2015
Gradient winds ahead of the line were gusting through the 30s mph
on average...with isolated reports of up to 45 mph at times. We
issued an SPS for such gusts/potential to cause minor damage thru
early morning hours as the line works into/across the
Pennyrile/WKY and SWIN.
Tabulated rainfall amounts are on track with 4 to 5 inches across
SEMO (isolated higher amounts)...where rain has all but ended.
Another 1-2" falling this morning as band marches on thru areas
east of MS river will spell storm total amounts in line with
models/forecast... 3 or 4" for remainder of Watch Area with
lesser amounts to 2" across our East. In collab with our
neighbors, we`ll expire FFA across nearly all of SEMO and retain
for areas along/east of MS river where rain still is ongoing.
Tracking of back edge suggests rain will be over for entire Watch
area by 15z, so we`ll make that adjustment as well. All rain
should depart FA by around 18z.
Afterward, High pressure works in and should gradually dry and
cool our atmosphere. We`ll slide back to 50s/30s for the remainder
of the short term forecast period, to finish out the work week.
.LONG TERM...(Friday night through Tuesday)
Issued at 231 AM CST WED NOV 18 2015
A significant pattern change will occur during the long term period.
A strong 500 mb shortwave will dig southeast across the mid and
upper Mississippi Valley on Friday night/Saturday. A second weaker
shortwave may follow a similar path Sunday. In the wake of these
shortwaves, a quasi-zonal flow pattern is expected next week. This
sequence of events is a sharp departure from the high amplitude
western trough/eastern ridge pattern that has been common this month.
As far as the daily details, a strong cold front will sweep
southeast across our region early Saturday. Forcing associated with
the digging 500 mb shortwave may generate scattered showers late
Friday night and Saturday morning. In the wake of the front, rather
strong northwest winds will usher in the coldest air so far this
season. Both the gfs and ecmwf indicate 850 mb temps will hover from
minus 5 to minus 9 Saturday night through Sunday. This will
translate to daytime highs struggling to reach 40 on Sunday. Under a
1030 mb surface high, overnight lows on both Saturday and Sunday
nights will be in the 20s.
Monday through Tuesday, a zonal flow pattern is expected across much
of the country. This will result in a continuation of mainly dry
conditions with slowly moderating temperatures. Highs will
recover to the lower 50s by Tuesday, with lows in the 30s.
&&
.AVIATION...
Issued at 1137 AM CST WED NOV 18 2015
The last of the rain showers should move out of the KOWB area
over the next hour. Winds will remain gusty out of the south
southwest up to 25-30kts at times. Winds will die down at sunset
and pick back up again when they shift to the west Thursday
morning. Biggest issue is what to do with the MVFR cigs that are
out to the west. A complete look moisture plots from varying
models suggests that the cigs could periodically dip into the MVFR
range the rest of today but better chances will definitely be
north of the area. Will play it a bit pessimistic and adjust with
satellite trends. A reinforcing cold front will arrive late
tonight into tomorrow morning which may bring another band of
clouds but it does not look too thick at this point.
&&
.PAH Watches/Warnings/Advisories...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
Area Forecast Discussion
National Weather Service Louisville KY
1233 PM EST WED NOV 18 2015
...Updated Forecast and Aviation Discussions...
...Forecast Update...
Issued at 1230 PM EST Wed Nov 18 2015
Steady rains continue to fall across much of the area. Some
locations over central KY especially near the TN border have
received just over 2 inches of rainfall. This has caused some minor
flooding issues reported in Logan and Butler counties. Thus, a
Flood Advy was issued for a few hrs until steady rains end there.
Will need to keep an eye on other locations over central KY that see
heavier bursts of rain which may cause more minor flooding issues.
No thunder reported over the region in quite some time so took the
slight chc t-storm mention out of the forecast. Rains should be
ending quickly from west to east late this afternoon into the
evening hrs.
A Wind Advisory remains in effect through 4pm EST. Behind the
steady rainfall, winds are expected to increase just ahead of and
along a frontal boundary advancing eastward. A good mixing zone
exists along a sharp pressure gradient along that boundary and obs
along that boundary are showing those higher gusts with 34 mph
observed at Huntingburg, IN ASOS and even higher gusts to the north
(40-50 mph over central Indiana). Although our gusts shouldn`t be
quite as high as those in central Indiana this afternoon, 35-45 mph
gusts over southern Indiana/central Kentucky look likely as this
boundary pushes through the region this afternoon. Thus the Wind
Advisory will remain in place.
.SHORT TERM (Now through Thursday)...
Issued at 230 AM EST Wed Nov 18 2015
....Windy Conditions Ahead of the Rains This Morning...
Seeing a steady increase in gradient winds early this morning, as a
strong low-level jet develops and pushes east across the region.
Gusts over our southwest forecast area are around 40 mph. Not too
far into the rain shield, winds are moderating over far western KY.
The main concern this morning is how windy it will get ahead of that
rain shield. Models continue to slow the eastward progress of the
line, now allowing a little more heating over our eastern zones.
That heating will lead to a higher mixing layer, which would allow
more of the stronger winds aloft to mix down to the surface. Would
not be surprised to see some 50 mph gusts mix down by mid to late
morning in areas just ahead of the rain shield...mainly east of a
Frankfort to Campbellsville line. The current wind advisory covers
this well.
As for the rains, the line is making steady progress eastward and
see no reason not to go with 100 pops areawide for the daytime
period. Totals should end up around an inch with isolated higher
amounts. Have lingered some rain chances in our east after 00Z, but
expect the region to be rain free by midnight.
Thursday a secondary cold front will sweep through the region,
turning winds from southwesterly tonight to westerly by Thursday
afternoon. The sunshine during the day will allow temperatures to
get up to near normal levels.
.LONG TERM (Thursday night through Tuesday)...
Issued at 230 AM EST Wed Nov 18 2015
Focii this period will be a cold front sweeping through the region
Saturday and then how cold it gets behind that front. We`ll start
off with a chilly morning Friday, but readings in the 30s are near
normal. High pressure will be right over the region, on its way to a
position off the mid Atlantic coast Saturday. A cold front will
sweep in here on the back side of that high. Moisture will be meager
for this front to work with, but the trough aloft and behind this
front should be strong enough to force at least a chance for
measurable precip during the day.
Models have backed off quite a bit in how much precip falls behind
this front Saturday night. The question has been how much of the
cold air pours in here before the precip exits the region. Given
that the timing now is during the day, and the model agreement in
this scenario, decided to remove the chance for light snow we had in
for Saturday night.
Sunday still looks to be the coldest day of the period, as high
pressure moves right over the Ohio Valley. Blended models continue
to come in colder with each run, but decided to go even lower,
closer to the European statistical guidance for highs Sunday, in the
upper 30s for all but south central Kentucky. These readings would
be roughly 20 degrees below normal!
After that day we moderate as the high settles over the Appalachians
and the trough aloft turns more into a zonal pattern.
&&
.AVIATION (18Z TAF Update)...
Updated at 1230 PM EST Wed Nov 18 2015
Current timing puts the back edge of the precip through BWG between
18-19z, SDF between 21-23z and closer to 00z at LEX. Expect
visibility in the heaviest rain to be 1-3sm. Ceilings will hang
around 2-2.5 kft, occasionally dropping into fuel-alternate or
rising to VFR. Once the rain ends, fast improvement to VFR ceilings
can be expected.
Winds will remain out of the south/southeast, gusting to 20-25 kts
at times, though the steadier rain has tempered that somewhat. Once
the rain ends, plan on a shift to the southwest and winds will pick
back up, especially at SDF/BWG where mixing during the daylight will
help.
Next concern is fog potential overnight as high pressure builds in
along with clearing skies. Combined with the recent rain, could see
fog develop at BWG. If the winds drop down, then expect a higher
chance of fog. For now, will advertise MVFR visbiliity restrictions,
but this may need to be lowered if confidence increases.
&&
.LMK Watches/Warnings/Advisories...
KY...Wind Advisory until 4 PM EST /3 PM CST/ this afternoon for
KYZ023>043-045>049-053>057-061>067-070>078-081-082.
IN...Wind Advisory until 4 PM EST /3 PM CST/ this afternoon for
INZ076>079-083-084-089>092.
&&
$$
Update.........AMS
Short Term.....RJS
Long Term......RJS
Aviation.......ZBT
Area Forecast Discussion
National Weather Service Louisville KY
851 AM EST WED NOV 18 2015
...Forecast Update...
Issued at 850 AM EST Wed Nov 18 2015
Updated the grids to adjust hourly POP timing and temps. POPs have
spread a little farther eastward quicker than previously forecast.
Wind gusts up to 40-45 mph have been observed ahead of the precip.
Gusts decline in the steady moderate rainfall, and then they will
pick up again during breaks of rainfall and on the back side where
rains are lighter. Thus, the Wind Advisory still looks good until
4pm at this point. May need to trim counties from west to east
behind the rains if wind gusts are underachieving. Expect high
temps ranging from the mid 60s to around 70 to be reached early this
afternoon with temps falling during the late afternoon/evening hours.
Issued at 515 AM EST Wed Nov 18 2015
Low-level winds reported by area VAD wind profiles as well as AMDAR
soundings are underachieving compared with what RAP fields suggested
the winds just above the surface should be. Still seeing a few gusts
into the 40-50 mph range this hour. So current wind advisory should
still work out. Have tweaked timing of highest pops to line up with
current radar trends and hourly reflectivity guidance. With each
tweak have tried to bump up winds and temperatures through the
morning just ahead (east) of the highest pops. Tweaks do not change
the zones, but have updated the point and click forecast for the web.
.SHORT TERM (Now through Thursday)...
Issued at 230 AM EST Wed Nov 18 2015
....Windy Conditions Ahead of the Rains This Morning...
Seeing a steady increase in gradient winds early this morning, as a
strong low-level jet develops and pushes east across the region.
Gusts over our southwest forecast area are around 40 mph. Not too
far into the rain shield, winds are moderating over far western KY.
The main concern this morning is how windy it will get ahead of that
rain shield. Models continue to slow the eastward progress of the
line, now allowing a little more heating over our eastern zones.
That heating will lead to a higher mixing layer, which would allow
more of the stronger winds aloft to mix down to the surface. Would
not be surprised to see some 50 mph gusts mix down by mid to late
morning in areas just ahead of the rain shield...mainly east of a
Frankfort to Campbellsville line. The current wind advisory covers
this well.
As for the rains, the line is making steady progress eastward and
see no reason not to go with 100 pops areawide for the daytime
period. Totals should end up around an inch with isolated higher
amounts. Have lingered some rain chances in our east after 00Z, but
expect the region to be rain free by midnight.
Thursday a secondary cold front will sweep through the region,
turning winds from southwesterly tonight to westerly by Thursday
afternoon. The sunshine during the day will allow temperatures to
get up to near normal levels.
.LONG TERM (Thursday night through Tuesday)...
Issued at 230 AM EST Wed Nov 18 2015
Focii this period will be a cold front sweeping through the region
Saturday and then how cold it gets behind that front. We`ll start
off with a chilly morning Friday, but readings in the 30s are near
normal. High pressure will be right over the region, on its way to a
position off the mid Atlantic coast Saturday. A cold front will
sweep in here on the back side of that high. Moisture will be meager
for this front to work with, but the trough aloft and behind this
front should be strong enough to force at least a chance for
measurable precip during the day.
Models have backed off quite a bit in how much precip falls behind
this front Saturday night. The question has been how much of the
cold air pours in here before the precip exits the region. Given
that the timing now is during the day, and the model agreement in
this scenario, decided to remove the chance for light snow we had in
for Saturday night.
Sunday still looks to be the coldest day of the period, as high
pressure moves right over the Ohio Valley. Blended models continue
to come in colder with each run, but decided to go even lower,
closer to the European statistical guidance for highs Sunday, in the
upper 30s for all but south central Kentucky. These readings would
be roughly 20 degrees below normal!
After that day we moderate as the high settles over the Appalachians
and the trough aloft turns more into a zonal pattern.
&&
.AVIATION (12Z TAF Update)...
Updated at 545 AM EST Wed Nov 18 2015
A strong low pressure system will continue to track northeast across
the middle of the country. With the pressure gradient tightening up,
winds are becoming gusty at all TAF sites this morning. Expect that
all sites will see sustained winds this morning in the 15-20 knot
range with gusts up to 35 knots. Gusts have the potential to be
higher at LEX this morning as precipitation will begin later and the
atmosphere has a chance to mix. However, these higher gusts should
be brief. Have kept the LLWS in for the next few hours, and the LLB
is then expected to lessen somewhat.
Moderate to potentially heavy rain will continue to slowly move
east. It should affect BWG first around 14Z, followed by SDF around
15Z and LEX around 18Z. With the heavier pockets of rain
visibilities may briefly go down to IFR. This rain will move out
this afternoon into the evening hours. Ceilings should then improve
and winds gusts will lessen after sunset.
&&
.LMK Watches/Warnings/Advisories...
KY...Wind Advisory until 4 PM EST /3 PM CST/ this afternoon for
KYZ023>043-045>049-053>057-061>067-070>078-081-082.
IN...Wind Advisory until 4 PM EST /3 PM CST/ this afternoon for
INZ076>079-083-084-089>092.
&&
$$
Update.........RJS/AMS
Short Term.....RJS
Long Term......RJS
Aviation.......EER
AREA FORECAST DISCUSSION
NWS JACKSON KY
650 AM EST WED NOV 18 2015
.UPDATE...
ISSUED AT 650 AM EST WED NOV 18 2015
THE BIG STORY WILL BE THE RAIN SHOWERS MOVING EAST INTO EASTERN KY
THIS AFTERNOON. DID MAKE SOME MINOR ADJUSTMENTS TO THE GRIDS IN
TERMS OF POPS TO SLOW DOWN SLIGHTLY GIVEN SOME OF THE MESO
MODELS...BUT OVERALL TIMING LOOKS ON TRACK. DID SOME MINOR TWEAKS
TO TEMPS/DEWS/WINDS TO LINE UP BETTER TO LATEST OBS AND TRENDS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 348 AM EST WED NOV 18 2015
THIS MORNING STRONG CLOSED LOW IS WELL ESTABLISHED ACROSS THE
CENTRAL PLAINS...WITH 00Z ANALYSIS ACROSS THE PLAINS SHOWING A
537MB HEIGHT WHICH IS ACTUALLY MIN FOR THIS DAY BASED ON SOUNDING
CLIMO. THIS JUST SPEAKS TO THE STRENGTH OF THIS POTENT
SYSTEM...WHICH WILL SWING A COLD FRONT ACROSS OUT AREA TODAY. THIS
LOW IS PROGGED PHASE WITH BROADER UPPER LOW ACROSS CANADA AND
OVERALL BROAD TROUGHING SETS UP ACROSS THE CENTRAL U.S. TO MID
ATLANTIC. WHILE RIDGING HOLD ON A BIT ACROSS THE NORTHEAST U.S.
INTO THE CANADIAN MARITIMES. WHILE THIS SYSTEM WILL USHER IN
COOLER AIR...THE COLDEST AIR WILL STAY LOCKED UP ACROSS THE
NORTHERN PLAINS TO THE WESTERN GREAT LAKES.
NOW THE DEEPER SURFACE LOW WILL TRACK NNE INTO THE UPPER
MIDWEST...WHILE ATTENDANT OCCLUDED FRONT AND TRIPLE POINT TRACK
EAST. THIS WILL BE OUR WEATHER MAKER TODAY BRINGING STRONG WINDS
AND WIDESPREAD RAIN SHOWERS ACROSS THE REGION TODAY. LETS TALK
WIND FIRST AS PRESSURE GRADIENT CONTINUES TO BECOME EVIDENT THIS
MORNING IN THE BATTLE GROUND BETWEEN THE DEEP LOW AND STRONG
SURFACE HIGH TO THE NORTHEAST. THIS WILL COUPLE WITH STRONG JET
ENERGY ALOFT WITH FORECAST SOUNDINGS AND PLAIN VIEW WINDS AT 850MB
INDICATING 70KT PLUS CORE RUNNING ACROSS THE REGION AS WE MOVE
TOWARD THE AFTERNOON. WE ARE ALREADY SEEING 30 TO 45 MPH GUST OF
BLACK MOUNTAIN THIS MORNING AND WHILE MIXING HEIGHTS WILL NOT BE
HIGH...AT OR BELOW 1000 FT IN GENERAL...IT WILL NOT TAKE MUCH
HEIGHT TO MIX DOWN SOME GUSTY WINDS. ALL THIS SAID THINK WE ARE IN
GOOD SHAPE WITH OVERALL TIMING OF HEADLINES AT THIS POINT.
NOW LETS DISCUSS THE PRECIP FOR THE EVENT WHICH WILL BE THE MOST
WE HAVE SEEN IN AT LEAST A MONTH NOW AND AT LEAST DOUBLE OUR
MONTHLY TOTAL SO FAR FOR NOV. THIS BAND OF MODERATE TO HEAVY RAIN
SHOWERS IS MAKING IT INTO FAR WESTERN KY THIS MORNING BASED ON
WSR-88D MOSAIC. AREAS IN FAR WEST ARE SEEING AROUND A INCH OF
PRECIP BASED ON MESONETS SINCE MIDNIGHT CST. NOW LOOKING AT RADAR
AND COMPARING SOME OF THE MESO MODELS THIS MORNING...THE ARW-NMM
SEEMS TO HAVE THE OVERALL BEST HANDLE ON TIMING. THE HRRR IS A BIT
SLOW BASED ON RADAR. THAT SAID OVERALL BEST CHANCES OF PRECIP WILL
BE THIS AFTERNOON AS STRONG LOW LEVEL JET SETS UP...NEARER THE
RIGHT ENTRANCE OF THE 300MB JET TO THE WEST...AND PWATS IN THE 1.4
OR HIGHER RANGE WHICH IS ABOVE NORMAL FOR BNA BASED ON SOUNDING
CLIMO. GIVEN THIS DID NOT CHANGE TOO MUCH WITH RESPECT TO TIMING
OF PRECIP...BUT PERHAPS A BIT SLOWER IN PROGRESSING IN OVERALL.
GENERALLY STUCK CLOSE TO THE CR BLEND FOR QPF...WHICH SEEMS TO
MATCH UP WELL OVERALL WITH THE NEIGHBORING OFFICES. THAT SAID
AMOUNTS ARE EXPECTED TO BE GENERALLY A INCH TO INCH AND A
QUARTER...BUT FAR SE COULD STILL SEE A BIT OF DOWNSLOPING WHICH
MAY HOLD THEM A BIT LOWER BUT NOT BY MUCH.
NOW FOR TONIGHT INTO THURSDAY FRONT SHOULD WORK OUT OF THE REGION
THROUGH THE EVENING AND GRADIENT/WINDS WILL WEAKEN. THE FORECAST
SOUNDINGS AND TIME HEIGHTS WOULD SUGGEST POSSIBLE STRATUS HANGING
TONIGHT OR PERHAPS FOG. RIGHT NOW WILL HOLD OFF ON LOWER CLOUDS
SINCE IT IS A BIT UNCERTAIN ON EXACTLY WHAT WILL OCCUR...WITH
CLEARING SKIES ARE QUICK BEHIND THIS FRONT DOWN STREAM. WHILE
WINDS WEAKEN WE SHOULD STAY SOME WHAT MIXED...BUT HIGH WILL BEGIN
NUDGING INTO THE REGION THROUGH THE DAY THURSDAY LEADING TO DRIER
CONDITIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 415 AM EST WED NOV 18 2015
A RATHER BROAD TROUGHING IS EXPECTED TO ENCOMPASS MUCH OF THE
CONUS FROM THE ROCKIES EAST INTO THE CENTRAL CONUS TO START THE
PERIOD WHILE A CLOSED UPPER LOW OVER WESTERN ONTARIO NORTH OF LAKE
SUPERIOR IS EXPECTED TO BE RETURNING NORTH. RIDGING AT THAT POINT
CENTERED NEAR CUBA AND THE BAHAMAS IS EXPECTED TO EXTEND NORTH
ACROSS PORTIONS OF THE WESTERN ATLANTIC. HOWEVER...THE 500 MB
TROUGH AXIS IS EXPECTED TO BE MOVE ACROSS THE COMMONWEALTH AND
LOWER OH VALLEY REGION AT THE START OF THE PERIOD WHILE HIGH
PRESSURE BUILDS IN AT THE SFC. BY FRIDAY THE BROAD TROUGH SHOULD
ENCOMPASS MUCH OF THE CONUS EAST OF THE ROCKIES.
A SHORTWAVE MOVING THROUGH THIS TROUGH IN THE NORTHERN STREAM
FROM THE ROCKIES AND SOUTHERN CANADA IS EXPECTED TO MOVE INTO THE
PLAINS...INTERACT WITH A SHORTWAVE ROTATING AROUND THE CANADIAN
UPPER LOW AND SHARPEN THE TROUGH OVER THE CENTRAL CONUS BY FRI
EVENING AND FRIDAY NIGHT. AT THAT POINT...SC HIGH PRESSURE WILL
BEGIN TO DEPART TO THE NORTHEAST HEIGHTS ACROSS EAST KY SHOULD
REMAIN NEARLY STEADY ON FRI ACROSS EAST KY. HEIGHTS SHOULD AGAIN
FALL AS THE NEXT SHORTWAVE TROUGH AND ASSOCIATED COLD FRONT
APPROACH THE LOWER OH VALLEY AND APPALACHIAN REGION FRI NIGHT AND
THEN MOVE ACROSS THE AREA SAT INTO SAT EVENING WITH LIMITED
MOISTURE. 850 MB TEMPS SHOULD DROP TO NEAR -9C OR -10C ON SAT
NIGHT AND THEN REMAIN NEAR THAT LEVEL INTO SUNDAY.
HEIGHT RISES ARE THEN EXPECTED AS THIS SYSTEM DEPARTS INTO AT
LEAST EARLY ON SUNDAY WITH SFC HIGH PRESSURE BUILDING TOWARD
EASTERN KY. HOWEVER...ONE MORE SHORTWAVE IS EXPECTED TO MOVE
ACROSS THE AREA TO END THE WEEKEND...BUT THERE ARE MODEL TIMING
DIFFERENCES WITH THIS AND MOISTURE SHOULD BE EVEN MORE LIMITED
THAN THE SHORTWAVE TROUGH ON SATURDAY SO NO MORE THAN MID AND HIGH
CLOUDS ARE ANTICIPATED. HEIGHTS SHOULD RISE AGAIN AT THE END OT
HE PERIOD...WITH SFC HIGH PRESSURE ARRIVE EARLY NEXT WEEK WITH SFC
AND UPPER LEVEL RIDGING DOMINATING. THE AIRMASS SHOULD ALSO
MODERATE WITH 85O MB TEMPS CLIMBING ABOVE 0C AND MAKING A RUN
TOWARD 5C BY THE END OF THE PERIOD.
TEMPERATURES SHOULD BE RATHER MILD IN THE 40S TO LOWER 50S AHEAD
OF THE SATURDAY TO SATURDAY EVENING COLD FRONT. TEMPERATURES WILL
DROP QUICKLY BEHIND THE FRONT...BUT DRIER AIR WILL ARRIVE QUICKLY
AS WELL. THERE IS A SMALL WINDOW ON SAT EVENING WHERE IF THE
MOISTURE LINGERED LONG ENOUGH AS THE COLUMN COOLS FOR A FEW FLAKES
TO MIX IN OR AN ISOLATED SNOW SHOWER OR TWO OR A FEW FLURRIES...
PARTICULARLY IN THE HIGHEST ELEVATIONS NEAR THE VA BORDER.
CONFIDENCE IN THIS REMAIN LOW HOWEVER...AS THE 0Z MODEL RUN
GENERALLY HAS THE LOW LEVELS DRYING OUT VERY QUICK...ECMWF...OR
PRESENCE OF ICE IN THE LOW CLOUDS PERHAPS ONLY FROM SEEDER FEEDER
IF THAT WERE TO OCCUR RIGHT AS THE MOISTURE DEPARTS. IF FLAKES DO
IN FACT OCCUR...NO ACCUMULATION IS EXPECTED.
TEMPERATURES ARE EXPECTED TO DROP WELL BELOW FREEZING SATURDAY
NIGHT...AS SKIES CLEAR AND BE EVEN COLDER SUNDAY NIGHT. BELOW
FREEZING TEMPERATURES FOR AT LEAST EASTERN VALLEYS ARE ALSO
EXPECTED ON MONDAY NIGHT. PENDING CLOUD COVER AND TIMING OF THE
SHORTWAVE TO MOVE ACROSS THE OHIO VALLEY...SOME TEENS WILL BE
POSSIBLE ON SUNDAY NIGHT AS SFC HIGH PRESSURE BUILDS IN. GFS
BASED COOP MOS GUIDANCE FOR MANY VALLEY LOCATIONS SUPPORTS TEENS
FOR SUN NIGHT WITH TEMPERATURES THERE WELL DOWN INTO THE 20S FOR
MON NIGHT AS WELL. TEMPERATURES WILL MODERATE ON MONDAY AND
TUESDAY...REACHING THE 40S MONDAY AND MID 40S TO LOWER 50S ON
TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 645 AM EST WED NOV 18 2015
THE START OF THE PERIOD HAS REMAINED VFR AND SHOULD UNTIL WE SEE
PRECIP MOVE INTO THE REGION FROM WEST TO EAST. THE BIGGER ISSUE
HAS BEEN THE GUSTY WINDS PARTICULARLY ALOFT...THE JKL VAD DOES
HAVE 40 KTS AT WHAT IS PROBABLY IS AROUND 2 KFT. THEREFORE
CONTINUE TO CARRY THE LLWS TILL LATER THIS MORNING WHEN WINDS ARE
EXPECTED TO INCREASE AREAWIDE. CERTAINLY EXPECTING AT LEAST 35KT
GUST AT MOST TAF SITES AT SOME POINT TODAY. A COLD FRONT WILL
MOVE ACROSS THE REGION TODAY BRINGING MODERATE TO HEAVY SHOWERS
ACROSS THE REGION AS WE MOVE INTO THE AFTERNOON HOURS. THIS WILL
LOWER TAF SITES DOWN TO MVFR OR PERHAPS LOWER IN HEAVIER SHOWERS.
WINDS WILL WANE TONIGHT AS GRADIENT RELAXES AND SKIES CLEAR.
DEPENDING ON WINDS AND RAINFALL FOG OR LOW STRATUS WILL CERTAINLY
BE POSSIBLE...BUT NOT CONFIDENT ON THIS AT THIS POINT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR KYZ044-050>052-
058>060-068-069-079-080-083>086-108-111-114-116.
WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ087-088-118-120.
WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ104-106-107-109-
110-112-113-115-117-119.
&&
$$
UPDATE...DJ
SHORT TERM...DJ
LONG TERM...JP
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
645 AM EST WED NOV 18 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 348 AM EST WED NOV 18 2015
THIS MORNING STRONG CLOSED LOW IS WELL ESTABLISHED ACROSS THE
CENTRAL PLAINS...WITH 00Z ANALYSIS ACROSS THE PLAINS SHOWING A
537MB HEIGHT WHICH IS ACTUALLY MIN FOR THIS DAY BASED ON SOUNDING
CLIMO. THIS JUST SPEAKS TO THE STRENGTH OF THIS POTENT
SYSTEM...WHICH WILL SWING A COLD FRONT ACROSS OUT AREA TODAY. THIS
LOW IS PROGGED PHASE WITH BROADER UPPER LOW ACROSS CANADA AND
OVERALL BROAD TROUGHING SETS UP ACROSS THE CENTRAL U.S. TO MID
ATLANTIC. WHILE RIDGING HOLD ON A BIT ACROSS THE NORTHEAST U.S.
INTO THE CANADIAN MARITIMES. WHILE THIS SYSTEM WILL USHER IN
COOLER AIR...THE COLDEST AIR WILL STAY LOCKED UP ACROSS THE
NORTHERN PLAINS TO THE WESTERN GREAT LAKES.
NOW THE DEEPER SURFACE LOW WILL TRACK NNE INTO THE UPPER
MIDWEST...WHILE ATTENDANT OCCLUDED FRONT AND TRIPLE POINT TRACK
EAST. THIS WILL BE OUR WEATHER MAKER TODAY BRINGING STRONG WINDS
AND WIDESPREAD RAIN SHOWERS ACROSS THE REGION TODAY. LETS TALK
WIND FIRST AS PRESSURE GRADIENT CONTINUES TO BECOME EVIDENT THIS
MORNING IN THE BATTLE GROUND BETWEEN THE DEEP LOW AND STRONG
SURFACE HIGH TO THE NORTHEAST. THIS WILL COUPLE WITH STRONG JET
ENERGY ALOFT WITH FORECAST SOUNDINGS AND PLAIN VIEW WINDS AT 850MB
INDICATING 70KT PLUS CORE RUNNING ACROSS THE REGION AS WE MOVE
TOWARD THE AFTERNOON. WE ARE ALREADY SEEING 30 TO 45 MPH GUST OF
BLACK MOUNTAIN THIS MORNING AND WHILE MIXING HEIGHTS WILL NOT BE
HIGH...AT OR BELOW 1000 FT IN GENERAL...IT WILL NOT TAKE MUCH
HEIGHT TO MIX DOWN SOME GUSTY WINDS. ALL THIS SAID THINK WE ARE IN
GOOD SHAPE WITH OVERALL TIMING OF HEADLINES AT THIS POINT.
NOW LETS DISCUSS THE PRECIP FOR THE EVENT WHICH WILL BE THE MOST
WE HAVE SEEN IN AT LEAST A MONTH NOW AND AT LEAST DOUBLE OUR
MONTHLY TOTAL SO FAR FOR NOV. THIS BAND OF MODERATE TO HEAVY RAIN
SHOWERS IS MAKING IT INTO FAR WESTERN KY THIS MORNING BASED ON
WSR-88D MOSAIC. AREAS IN FAR WEST ARE SEEING AROUND A INCH OF
PRECIP BASED ON MESONETS SINCE MIDNIGHT CST. NOW LOOKING AT RADAR
AND COMPARING SOME OF THE MESO MODELS THIS MORNING...THE ARW-NMM
SEEMS TO HAVE THE OVERALL BEST HANDLE ON TIMING. THE HRRR IS A BIT
SLOW BASED ON RADAR. THAT SAID OVERALL BEST CHANCES OF PRECIP WILL
BE THIS AFTERNOON AS STRONG LOW LEVEL JET SETS UP...NEARER THE
RIGHT ENTRANCE OF THE 300MB JET TO THE WEST...AND PWATS IN THE 1.4
OR HIGHER RANGE WHICH IS ABOVE NORMAL FOR BNA BASED ON SOUNDING
CLIMO. GIVEN THIS DID NOT CHANGE TOO MUCH WITH RESPECT TO TIMING
OF PRECIP...BUT PERHAPS A BIT SLOWER IN PROGRESSING IN OVERALL.
GENERALLY STUCK CLOSE TO THE CR BLEND FOR QPF...WHICH SEEMS TO
MATCH UP WELL OVERALL WITH THE NEIGHBORING OFFICES. THAT SAID
AMOUNTS ARE EXPECTED TO BE GENERALLY A INCH TO INCH AND A
QUARTER...BUT FAR SE COULD STILL SEE A BIT OF DOWNSLOPING WHICH
MAY HOLD THEM A BIT LOWER BUT NOT BY MUCH.
NOW FOR TONIGHT INTO THURSDAY FRONT SHOULD WORK OUT OF THE REGION
THROUGH THE EVENING AND GRADIENT/WINDS WILL WEAKEN. THE FORECAST
SOUNDINGS AND TIME HEIGHTS WOULD SUGGEST POSSIBLE STRATUS HANGING
TONIGHT OR PERHAPS FOG. RIGHT NOW WILL HOLD OFF ON LOWER CLOUDS
SINCE IT IS A BIT UNCERTAIN ON EXACTLY WHAT WILL OCCUR...WITH
CLEARING SKIES ARE QUICK BEHIND THIS FRONT DOWN STREAM. WHILE
WINDS WEAKEN WE SHOULD STAY SOME WHAT MIXED...BUT HIGH WILL BEGIN
NUDGING INTO THE REGION THROUGH THE DAY THURSDAY LEADING TO DRIER
CONDITIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 415 AM EST WED NOV 18 2015
A RATHER BROAD TROUGHING IS EXPECTED TO ENCOMPASS MUCH OF THE
CONUS FROM THE ROCKIES EAST INTO THE CENTRAL CONUS TO START THE
PERIOD WHILE A CLOSED UPPER LOW OVER WESTERN ONTARIO NORTH OF LAKE
SUPERIOR IS EXPECTED TO BE RETURNING NORTH. RIDGING AT THAT POINT
CENTERED NEAR CUBA AND THE BAHAMAS IS EXPECTED TO EXTEND NORTH
ACROSS PORTIONS OF THE WESTERN ATLANTIC. HOWEVER...THE 500 MB
TROUGH AXIS IS EXPECTED TO BE MOVE ACROSS THE COMMONWEALTH AND
LOWER OH VALLEY REGION AT THE START OF THE PERIOD WHILE HIGH
PRESSURE BUILDS IN AT THE SFC. BY FRIDAY THE BROAD TROUGH SHOULD
ENCOMPASS MUCH OF THE CONUS EAST OF THE ROCKIES.
A SHORTWAVE MOVING THROUGH THIS TROUGH IN THE NORTHERN STREAM
FROM THE ROCKIES AND SOUTHERN CANADA IS EXPECTED TO MOVE INTO THE
PLAINS...INTERACT WITH A SHORTWAVE ROTATING AROUND THE CANADIAN
UPPER LOW AND SHARPEN THE TROUGH OVER THE CENTRAL CONUS BY FRI
EVENING AND FRIDAY NIGHT. AT THAT POINT...SC HIGH PRESSURE WILL
BEGIN TO DEPART TO THE NORTHEAST HEIGHTS ACROSS EAST KY SHOULD
REMAIN NEARLY STEADY ON FRI ACROSS EAST KY. HEIGHTS SHOULD AGAIN
FALL AS THE NEXT SHORTWAVE TROUGH AND ASSOCIATED COLD FRONT
APPROACH THE LOWER OH VALLEY AND APPALACHIAN REGION FRI NIGHT AND
THEN MOVE ACROSS THE AREA SAT INTO SAT EVENING WITH LIMITED
MOISTURE. 850 MB TEMPS SHOULD DROP TO NEAR -9C OR -10C ON SAT
NIGHT AND THEN REMAIN NEAR THAT LEVEL INTO SUNDAY.
HEIGHT RISES ARE THEN EXPECTED AS THIS SYSTEM DEPARTS INTO AT
LEAST EARLY ON SUNDAY WITH SFC HIGH PRESSURE BUILDING TOWARD
EASTERN KY. HOWEVER...ONE MORE SHORTWAVE IS EXPECTED TO MOVE
ACROSS THE AREA TO END THE WEEKEND...BUT THERE ARE MODEL TIMING
DIFFERENCES WITH THIS AND MOISTURE SHOULD BE EVEN MORE LIMITED
THAN THE SHORTWAVE TROUGH ON SATURDAY SO NO MORE THAN MID AND HIGH
CLOUDS ARE ANTICIPATED. HEIGHTS SHOULD RISE AGAIN AT THE END OT
HE PERIOD...WITH SFC HIGH PRESSURE ARRIVE EARLY NEXT WEEK WITH SFC
AND UPPER LEVEL RIDGING DOMINATING. THE AIRMASS SHOULD ALSO
MODERATE WITH 85O MB TEMPS CLIMBING ABOVE 0C AND MAKING A RUN
TOWARD 5C BY THE END OF THE PERIOD.
TEMPERATURES SHOULD BE RATHER MILD IN THE 40S TO LOWER 50S AHEAD
OF THE SATURDAY TO SATURDAY EVENING COLD FRONT. TEMPERATURES WILL
DROP QUICKLY BEHIND THE FRONT...BUT DRIER AIR WILL ARRIVE QUICKLY
AS WELL. THERE IS A SMALL WINDOW ON SAT EVENING WHERE IF THE
MOISTURE LINGERED LONG ENOUGH AS THE COLUMN COOLS FOR A FEW FLAKES
TO MIX IN OR AN ISOLATED SNOW SHOWER OR TWO OR A FEW FLURRIES...
PARTICULARLY IN THE HIGHEST ELEVATIONS NEAR THE VA BORDER.
CONFIDENCE IN THIS REMAIN LOW HOWEVER...AS THE 0Z MODEL RUN
GENERALLY HAS THE LOW LEVELS DRYING OUT VERY QUICK...ECMWF...OR
PRESENCE OF ICE IN THE LOW CLOUDS PERHAPS ONLY FROM SEEDER FEEDER
IF THAT WERE TO OCCUR RIGHT AS THE MOISTURE DEPARTS. IF FLAKES DO
IN FACT OCCUR...NO ACCUMULATION IS EXPECTED.
TEMPERATURES ARE EXPECTED TO DROP WELL BELOW FREEZING SATURDAY
NIGHT...AS SKIES CLEAR AND BE EVEN COLDER SUNDAY NIGHT. BELOW
FREEZING TEMPERATURES FOR AT LEAST EASTERN VALLEYS ARE ALSO
EXPECTED ON MONDAY NIGHT. PENDING CLOUD COVER AND TIMING OF THE
SHORTWAVE TO MOVE ACROSS THE OHIO VALLEY...SOME TEENS WILL BE
POSSIBLE ON SUNDAY NIGHT AS SFC HIGH PRESSURE BUILDS IN. GFS
BASED COOP MOS GUIDANCE FOR MANY VALLEY LOCATIONS SUPPORTS TEENS
FOR SUN NIGHT WITH TEMPERATURES THERE WELL DOWN INTO THE 20S FOR
MON NIGHT AS WELL. TEMPERATURES WILL MODERATE ON MONDAY AND
TUESDAY...REACHING THE 40S MONDAY AND MID 40S TO LOWER 50S ON
TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 645 AM EST WED NOV 18 2015
THE START OF THE PERIOD HAS REMAINED VFR AND SHOULD UNTIL WE SEE
PRECIP MOVE INTO THE REGION FROM WEST TO EAST. THE BIGGER ISSUE
HAS BEEN THE GUSTY WINDS PARTICULARLY ALOFT...THE JKL VAD DOES
HAVE 40 KTS AT WHAT IS PROBABLY IS AROUND 2 KFT. THEREFORE
CONTINUE TO CARRY THE LLWS TILL LATER THIS MORNING WHEN WINDS ARE
EXPECTED TO INCREASE AREAWIDE. CERTAINLY EXPECTING AT LEAST 35KT
GUST AT MOST TAF SITES AT SOME POINT TODAY. A COLD FRONT WILL
MOVE ACROSS THE REGION TODAY BRINGING MODERATE TO HEAVY SHOWERS
ACROSS THE REGION AS WE MOVE INTO THE AFTERNOON HOURS. THIS WILL
LOWER TAF SITES DOWN TO MVFR OR PERHAPS LOWER IN HEAVIER SHOWERS.
WINDS WILL WANE TONIGHT AS GRADIENT RELAXES AND SKIES CLEAR.
DEPENDING ON WINDS AND RAINFALL FOG OR LOW STRATUS WILL CERTAINLY
BE POSSIBLE...BUT NOT CONFIDENT ON THIS AT THIS POINT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR KYZ044-050>052-
058>060-068-069-079-080-083>086-108-111-114-116.
WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ087-088-118-120.
WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ104-106-107-109-
110-112-113-115-117-119.
&&
$$
SHORT TERM...DJ
LONG TERM...JP
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
455 AM EST WED NOV 18 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 348 AM EST WED NOV 18 2015
THIS MORNING STRONG CLOSED LOW IS WELL ESTABLISHED ACROSS THE
CENTRAL PLAINS...WITH 00Z ANALYSIS ACROSS THE PLAINS SHOWING A
537MB HEIGHT WHICH IS ACTUALLY MIN FOR THIS DAY BASED ON SOUNDING
CLIMO. THIS JUST SPEAKS TO THE STRENGTH OF THIS POTENT
SYSTEM...WHICH WILL SWING A COLD FRONT ACROSS OUT AREA TODAY. THIS
LOW IS PROGGED PHASE WITH BROADER UPPER LOW ACROSS CANADA AND
OVERALL BROAD TROUGHING SETS UP ACROSS THE CENTRAL U.S. TO MID
ATLANTIC. WHILE RIDGING HOLD ON A BIT ACROSS THE NORTHEAST U.S.
INTO THE CANADIAN MARITIMES. WHILE THIS SYSTEM WILL USHER IN
COOLER AIR...THE COLDEST AIR WILL STAY LOCKED UP ACROSS THE
NORTHERN PLAINS TO THE WESTERN GREAT LAKES.
NOW THE DEEPER SURFACE LOW WILL TRACK NNE INTO THE UPPER
MIDWEST...WHILE ATTENDANT OCCLUDED FRONT AND TRIPLE POINT TRACK
EAST. THIS WILL BE OUR WEATHER MAKER TODAY BRINGING STRONG WINDS
AND WIDESPREAD RAIN SHOWERS ACROSS THE REGION TODAY. LETS TALK
WIND FIRST AS PRESSURE GRADIENT CONTINUES TO BECOME EVIDENT THIS
MORNING IN THE BATTLE GROUND BETWEEN THE DEEP LOW AND STRONG
SURFACE HIGH TO THE NORTHEAST. THIS WILL COUPLE WITH STRONG JET
ENERGY ALOFT WITH FORECAST SOUNDINGS AND PLAIN VIEW WINDS AT 850MB
INDICATING 70KT PLUS CORE RUNNING ACROSS THE REGION AS WE MOVE
TOWARD THE AFTERNOON. WE ARE ALREADY SEEING 30 TO 45 MPH GUST OF
BLACK MOUNTAIN THIS MORNING AND WHILE MIXING HEIGHTS WILL NOT BE
HIGH...AT OR BELOW 1000 FT IN GENERAL...IT WILL NOT TAKE MUCH
HEIGHT TO MIX DOWN SOME GUSTY WINDS. ALL THIS SAID THINK WE ARE IN
GOOD SHAPE WITH OVERALL TIMING OF HEADLINES AT THIS POINT.
NOW LETS DISCUSS THE PRECIP FOR THE EVENT WHICH WILL BE THE MOST
WE HAVE SEEN IN AT LEAST A MONTH NOW AND AT LEAST DOUBLE OUR
MONTHLY TOTAL SO FAR FOR NOV. THIS BAND OF MODERATE TO HEAVY RAIN
SHOWERS IS MAKING IT INTO FAR WESTERN KY THIS MORNING BASED ON
WSR-88D MOSAIC. AREAS IN FAR WEST ARE SEEING AROUND A INCH OF
PRECIP BASED ON MESONETS SINCE MIDNIGHT CST. NOW LOOKING AT RADAR
AND COMPARING SOME OF THE MESO MODELS THIS MORNING...THE ARW-NMM
SEEMS TO HAVE THE OVERALL BEST HANDLE ON TIMING. THE HRRR IS A BIT
SLOW BASED ON RADAR. THAT SAID OVERALL BEST CHANCES OF PRECIP WILL
BE THIS AFTERNOON AS STRONG LOW LEVEL JET SETS UP...NEARER THE
RIGHT ENTRANCE OF THE 300MB JET TO THE WEST...AND PWATS IN THE 1.4
OR HIGHER RANGE WHICH IS ABOVE NORMAL FOR BNA BASED ON SOUNDING
CLIMO. GIVEN THIS DID NOT CHANGE TOO MUCH WITH RESPECT TO TIMING
OF PRECIP...BUT PERHAPS A BIT SLOWER IN PROGRESSING IN OVERALL.
GENERALLY STUCK CLOSE TO THE CR BLEND FOR QPF...WHICH SEEMS TO
MATCH UP WELL OVERALL WITH THE NEIGHBORING OFFICES. THAT SAID
AMOUNTS ARE EXPECTED TO BE GENERALLY A INCH TO INCH AND A
QUARTER...BUT FAR SE COULD STILL SEE A BIT OF DOWNSLOPING WHICH
MAY HOLD THEM A BIT LOWER BUT NOT BY MUCH.
NOW FOR TONIGHT INTO THURSDAY FRONT SHOULD WORK OUT OF THE REGION
THROUGH THE EVENING AND GRADIENT/WINDS WILL WEAKEN. THE FORECAST
SOUNDINGS AND TIME HEIGHTS WOULD SUGGEST POSSIBLE STRATUS HANGING
TONIGHT OR PERHAPS FOG. RIGHT NOW WILL HOLD OFF ON LOWER CLOUDS
SINCE IT IS A BIT UNCERTAIN ON EXACTLY WHAT WILL OCCUR...WITH
CLEARING SKIES ARE QUICK BEHIND THIS FRONT DOWN STREAM. WHILE
WINDS WEAKEN WE SHOULD STAY SOME WHAT MIXED...BUT HIGH WILL BEGIN
NUDGING INTO THE REGION THROUGH THE DAY THURSDAY LEADING TO DRIER
CONDITIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 415 AM EST WED NOV 18 2015
A RATHER BROAD TROUGHING IS EXPECTED TO ENCOMPASS MUCH OF THE
CONUS FROM THE ROCKIES EAST INTO THE CENTRAL CONUS TO START THE
PERIOD WHILE A CLOSED UPPER LOW OVER WESTERN ONTARIO NORTH OF LAKE
SUPERIOR IS EXPECTED TO BE RETURNING NORTH. RIDGING AT THAT POINT
CENTERED NEAR CUBA AND THE BAHAMAS IS EXPECTED TO EXTEND NORTH
ACROSS PORTIONS OF THE WESTERN ATLANTIC. HOWEVER...THE 500 MB
TROUGH AXIS IS EXPECTED TO BE MOVE ACROSS THE COMMONWEALTH AND
LOWER OH VALLEY REGION AT THE START OF THE PERIOD WHILE HIGH
PRESSURE BUILDS IN AT THE SFC. BY FRIDAY THE BROAD TROUGH SHOULD
ENCOMPASS MUCH OF THE CONUS EAST OF THE ROCKIES.
A SHORTWAVE MOVING THROUGH THIS TROUGH IN THE NORTHERN STREAM
FROM THE ROCKIES AND SOUTHERN CANADA IS EXPECTED TO MOVE INTO THE
PLAINS...INTERACT WITH A SHORTWAVE ROTATING AROUND THE CANADIAN
UPPER LOW AND SHARPEN THE TROUGH OVER THE CENTRAL CONUS BY FRI
EVENING AND FRIDAY NIGHT. AT THAT POINT...SC HIGH PRESSURE WILL
BEGIN TO DEPART TO THE NORTHEAST HEIGHTS ACROSS EAST KY SHOULD
REMAIN NEARLY STEADY ON FRI ACROSS EAST KY. HEIGHTS SHOULD AGAIN
FALL AS THE NEXT SHORTWAVE TROUGH AND ASSOCIATED COLD FRONT
APPROACH THE LOWER OH VALLEY AND APPALACHIAN REGION FRI NIGHT AND
THEN MOVE ACROSS THE AREA SAT INTO SAT EVENING WITH LIMITED
MOISTURE. 850 MB TEMPS SHOULD DROP TO NEAR -9C OR -10C ON SAT
NIGHT AND THEN REMAIN NEAR THAT LEVEL INTO SUNDAY.
HEIGHT RISES ARE THEN EXPECTED AS THIS SYSTEM DEPARTS INTO AT
LEAST EARLY ON SUNDAY WITH SFC HIGH PRESSURE BUILDING TOWARD
EASTERN KY. HOWEVER...ONE MORE SHORTWAVE IS EXPECTED TO MOVE
ACROSS THE AREA TO END THE WEEKEND...BUT THERE ARE MODEL TIMING
DIFFERENCES WITH THIS AND MOISTURE SHOULD BE EVEN MORE LIMITED
THAN THE SHORTWAVE TROUGH ON SATURDAY SO NO MORE THAN MID AND HIGH
CLOUDS ARE ANTICIPATED. HEIGHTS SHOULD RISE AGAIN AT THE END OT
HE PERIOD...WITH SFC HIGH PRESSURE ARRIVE EARLY NEXT WEEK WITH SFC
AND UPPER LEVEL RIDGING DOMINATING. THE AIRMASS SHOULD ALSO
MODERATE WITH 85O MB TEMPS CLIMBING ABOVE 0C AND MAKING A RUN
TOWARD 5C BY THE END OF THE PERIOD.
TEMPERATURES SHOULD BE RATHER MILD IN THE 40S TO LOWER 50S AHEAD
OF THE SATURDAY TO SATURDAY EVENING COLD FRONT. TEMPERATURES WILL
DROP QUICKLY BEHIND THE FRONT...BUT DRIER AIR WILL ARRIVE QUICKLY
AS WELL. THERE IS A SMALL WINDOW ON SAT EVENING WHERE IF THE
MOISTURE LINGERED LONG ENOUGH AS THE COLUMN COOLS FOR A FEW FLAKES
TO MIX IN OR AN ISOLATED SNOW SHOWER OR TWO OR A FEW FLURRIES...
PARTICULARLY IN THE HIGHEST ELEVATIONS NEAR THE VA BORDER.
CONFIDENCE IN THIS REMAIN LOW HOWEVER...AS THE 0Z MODEL RUN
GENERALLY HAS THE LOW LEVELS DRYING OUT VERY QUICK...ECMWF...OR
PRESENCE OF ICE IN THE LOW CLOUDS PERHAPS ONLY FROM SEEDER FEEDER
IF THAT WERE TO OCCUR RIGHT AS THE MOISTURE DEPARTS. IF FLAKES DO
IN FACT OCCUR...NO ACCUMULATION IS EXPECTED.
TEMPERATURES ARE EXPECTED TO DROP WELL BELOW FREEZING SATURDAY
NIGHT...AS SKIES CLEAR AND BE EVEN COLDER SUNDAY NIGHT. BELOW
FREEZING TEMPERATURES FOR AT LEAST EASTERN VALLEYS ARE ALSO
EXPECTED ON MONDAY NIGHT. PENDING CLOUD COVER AND TIMING OF THE
SHORTWAVE TO MOVE ACROSS THE OHIO VALLEY...SOME TEENS WILL BE
POSSIBLE ON SUNDAY NIGHT AS SFC HIGH PRESSURE BUILDS IN. GFS
BASED COOP MOS GUIDANCE FOR MANY VALLEY LOCATIONS SUPPORTS TEENS
FOR SUN NIGHT WITH TEMPERATURES THERE WELL DOWN INTO THE 20S FOR
MON NIGHT AS WELL. TEMPERATURES WILL MODERATE ON MONDAY AND
TUESDAY...REACHING THE 40S MONDAY AND MID 40S TO LOWER 50S ON
TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1248 AM EST WED NOV 18 2015
THE TAF PERIOD WILL BE MEET WITH VFR CONDITIONS WITH EVEN SOME
CLEARING SKIES BEING SEEN ACROSS THE REGION THIS HOUR. STILL
EXPECTING WIND TO BE A ISSUE WITH A FEW SITES ALREADY SEEING 15
TO 20KT GUSTS TONIGHT AND INCREASING LATER TODAY WITH MIXING FROM
JET ALOFT. THE JET ALOFT WILL CAUSE PROBLEMS TONIGHT WITH RESPECT
TO LLWS BEING A REAL POSSIBILITY...SO KEPT THAT IN FROM THE
PREVIOUS TAF. STARTED IT AT ALL SITES GIVEN WE WILL SEE THE JET
RAMPING UP OVERNIGHT FOR SIMPLICITY PURPOSES. BY LATER TODAY AS
MENTIONED ABOVE INCREASING SOUTHERLY FLOW AND MIXING WILL BRING
GUSTY WINDS THROUGH THE REGION WITH GUSTS UP TO 35 KTS. A COLD
FRONT WILL MOVE ACROSS THE REGION THIS AFTERNOON AND EVENING AND
THIS WILL BRING INCREASES IN THE WINDS...RAIN SHOWERS...AND
LOWERING CIGS. RIGHT NOW STICKING WITH MVFR BUT PERHAPS LOWER AT
TIMES WITH HEAVIER SHOWERS. OVERALL DID OPT TO BRING WINDS DOWN AS
WE MOVE PAST THE 00Z TIME FRAME PROGRESSIVELY ACROSS THE TAF SITES
FROM WEST TO EAST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR KYZ044-050>052-
058>060-068-069-079-080-083>086-108-111-114-116.
WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ087-088-118-120.
WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR KYZ104-106-107-109-110-112-113-115-117-119.
&&
$$
SHORT TERM...DJ
LONG TERM...JP
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
348 AM EST WED NOV 18 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 348 AM EST WED NOV 18 2015
THIS MORNING STRONG CLOSED LOW IS WELL ESTABLISHED ACROSS THE
CENTRAL PLAINS...WITH 00Z ANALYSIS ACROSS THE PLAINS SHOWING A
537MB HEIGHT WHICH IS ACTUALLY MIN FOR THIS DAY BASED ON SOUNDING
CLIMO. THIS JUST SPEAKS TO THE STRENGTH OF THIS POTENT
SYSTEM...WHICH WILL SWING A COLD FRONT ACROSS OUT AREA TODAY. THIS
LOW IS PROGGED PHASE WITH BROADER UPPER LOW ACROSS CANADA AND
OVERALL BROAD TROUGHING SETS UP ACROSS THE CENTRAL U.S. TO MID
ATLANTIC. WHILE RIDGING HOLD ON A BIT ACROSS THE NORTHEAST U.S.
INTO THE CANADIAN MARITIMES. WHILE THIS SYSTEM WILL USHER IN
COOLER AIR...THE COLDEST AIR WILL STAY LOCKED UP ACROSS THE
NORTHERN PLAINS TO THE WESTERN GREAT LAKES.
NOW THE DEEPER SURFACE LOW WILL TRACK NNE INTO THE UPPER
MIDWEST...WHILE ATTENDANT OCCLUDED FRONT AND TRIPLE POINT TRACK
EAST. THIS WILL BE OUR WEATHER MAKER TODAY BRINGING STRONG WINDS
AND WIDESPREAD RAIN SHOWERS ACROSS THE REGION TODAY. LETS TALK
WIND FIRST AS PRESSURE GRADIENT CONTINUES TO BECOME EVIDENT THIS
MORNING IN THE BATTLE GROUND BETWEEN THE DEEP LOW AND STRONG
SURFACE HIGH TO THE NORTHEAST. THIS WILL COUPLE WITH STRONG JET
ENERGY ALOFT WITH FORECAST SOUNDINGS AND PLAIN VIEW WINDS AT 850MB
INDICATING 70KT PLUS CORE RUNNING ACROSS THE REGION AS WE MOVE
TOWARD THE AFTERNOON. WE ARE ALREADY SEEING 30 TO 45 MPH GUST OF
BLACK MOUNTAIN THIS MORNING AND WHILE MIXING HEIGHTS WILL NOT BE
HIGH...AT OR BELOW 1000 FT IN GENERAL...IT WILL NOT TAKE MUCH
HEIGHT TO MIX DOWN SOME GUSTY WINDS. ALL THIS SAID THINK WE ARE IN
GOOD SHAPE WITH OVERALL TIMING OF HEADLINES AT THIS POINT.
NOW LETS DISCUSS THE PRECIP FOR THE EVENT WHICH WILL BE THE MOST
WE HAVE SEEN IN AT LEAST A MONTH NOW AND AT LEAST DOUBLE OUR
MONTHLY TOTAL SO FAR FOR NOV. THIS BAND OF MODERATE TO HEAVY RAIN
SHOWERS IS MAKING IT INTO FAR WESTERN KY THIS MORNING BASED ON
WSR-88D MOSAIC. AREAS IN FAR WEST ARE SEEING AROUND A INCH OF
PRECIP BASED ON MESONETS SINCE MIDNIGHT CST. NOW LOOKING AT RADAR
AND COMPARING SOME OF THE MESO MODELS THIS MORNING...THE ARW-NMM
SEEMS TO HAVE THE OVERALL BEST HANDLE ON TIMING. THE HRRR IS A BIT
SLOW BASED ON RADAR. THAT SAID OVERALL BEST CHANCES OF PRECIP WILL
BE THIS AFTERNOON AS STRONG LOW LEVEL JET SETS UP...NEARER THE
RIGHT ENTRANCE OF THE 300MB JET TO THE WEST...AND PWATS IN THE 1.4
OR HIGHER RANGE WHICH IS ABOVE NORMAL FOR BNA BASED ON SOUNDING
CLIMO. GIVEN THIS DID NOT CHANGE TOO MUCH WITH RESPECT TO TIMING
OF PRECIP...BUT PERHAPS A BIT SLOWER IN PROGRESSING IN OVERALL.
GENERALLY STUCK CLOSE TO THE CR BLEND FOR QPF...WHICH SEEMS TO
MATCH UP WELL OVERALL WITH THE NEIGHBORING OFFICES. THAT SAID
AMOUNTS ARE EXPECTED TO BE GENERALLY A INCH TO INCH AND A
QUARTER...BUT FAR SE COULD STILL SEE A BIT OF DOWNSLOPING WHICH
MAY HOLD THEM A BIT LOWER BUT NOT BY MUCH.
NOW FOR TONIGHT INTO THURSDAY FRONT SHOULD WORK OUT OF THE REGION
THROUGH THE EVENING AND GRADIENT/WINDS WILL WEAKEN. THE FORECAST
SOUNDINGS AND TIME HEIGHTS WOULD SUGGEST POSSIBLE STRATUS HANGING
TONIGHT OR PERHAPS FOG. RIGHT NOW WILL HOLD OFF ON LOWER CLOUDS
SINCE IT IS A BIT UNCERTAIN ON EXACTLY WHAT WILL OCCUR...WITH
CLEARING SKIES ARE QUICK BEHIND THIS FRONT DOWN STREAM. WHILE
WINDS WEAKEN WE SHOULD STAY SOME WHAT MIXED...BUT HIGH WILL BEGIN
NUDGING INTO THE REGION THROUGH THE DAY THURSDAY LEADING TO DRIER
CONDITIONS.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 348 AM EST WED NOV 18 2015
COMING SOON...
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1248 AM EST WED NOV 18 2015
THE TAF PERIOD WILL BE MEET WITH VFR CONDITIONS WITH EVEN SOME
CLEARING SKIES BEING SEEN ACROSS THE REGION THIS HOUR. STILL
EXPECTING WIND TO BE A ISSUE WITH A FEW SITES ALREADY SEEING 15
TO 20KT GUSTS TONIGHT AND INCREASING LATER TODAY WITH MIXING FROM
JET ALOFT. THE JET ALOFT WILL CAUSE PROBLEMS TONIGHT WITH RESPECT
TO LLWS BEING A REAL POSSIBILITY...SO KEPT THAT IN FROM THE
PREVIOUS TAF. STARTED IT AT ALL SITES GIVEN WE WILL SEE THE JET
RAMPING UP OVERNIGHT FOR SIMPLICITY PURPOSES. BY LATER TODAY AS
MENTIONED ABOVE INCREASING SOUTHERLY FLOW AND MIXING WILL BRING
GUSTY WINDS THROUGH THE REGION WITH GUSTS UP TO 35 KTS. A COLD
FRONT WILL MOVE ACROSS THE REGION THIS AFTERNOON AND EVENING AND
THIS WILL BRING INCREASES IN THE WINDS...RAIN SHOWERS...AND
LOWERING CIGS. RIGHT NOW STICKING WITH MVFR BUT PERHAPS LOWER AT
TIMES WITH HEAVIER SHOWERS. OVERALL DID OPT TO BRING WINDS DOWN AS
WE MOVE PAST THE 00Z TIME FRAME PROGRESSIVELY ACROSS THE TAF SITES
FROM WEST TO EAST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR KYZ044-050>052-
058>060-068-069-079-080-083>086-108-111-114-116.
WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ087-088-118-120.
WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR KYZ104-106-107-109-110-112-113-115-117-119.
&&
$$
SHORT TERM...DJ
LONG TERM...JP
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
ISSUED BY NATIONAL WEATHER SERVICE CHARLESTON WV
301 PM EST WED NOV 18 2015
.SYNOPSIS...
COLD FRONT CROSSES LATE TONIGHT. COOLER WITH HIGH PRESSURE
THURSDAY NIGHT INTO FRIDAY NIGHT. VIGOROUS COLD FRONT WHIPS
THROUGH LATE SATURDAY/EARLY SATURDAY NIGHT. MUCH COLDER IN WAKE.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
TIGHTENING PRESSURE GRADIENT AND DOWNSLOPING FLOW ARE EXPECTED TO
HELP SUSTAIN WIND GUSTS TODAY AS A COLD FRONT APPROACHES FROM THE
WEST. ACROSS THE RIDGE TOPS AND VALLEYS NEARBY...WIND GUSTS ARE
EXPECTED TO REACH ADVISORY CRITERIA WHILE THE LOW LEVEL JET
ENHANCES IN RESPONSE TO THE STRENGTHENING SURFACE LOW PROGGED TO
SHIFT OVER THE WESTERN GREAT LAKES. HI-RES AND RAP MODEL SOUNDINGS
ALSO INDICATES STRONGER...BUT SHALLOW MIXING AS TEMPERATURES RISE
IN THE AFTERNOON. THEREFORE A WIND ADVISORY WAS ISSUED FOR THE
RIDGE ZONES AND VALLEYS WITHIN.
LOW LEVEL MOISTURE TRANSPORT VIA SOUTHEAST FLOW MAY CAUSE LIGHT
QPF ACROSS THE RIDGES DUE TO OROGRAPHIC LIFT. HAVE MAINTAINED
CHANCE POPS IN THE HIGHER TERRAIN UNTIL THE FRONT APPROACHES.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SUNDAY/...
THE LINGERING STRATOCUMULUS CLOUDS SHOULD BE DISSOLVING
THURSDAY NIGHT. STILL RELATIVELY TRANQUIL ENVIRONMENT FIGURED
WITH HIGH PRESSURE FRIDAY INTO FRIDAY NIGHT.
VIGOROUS 500M MB SHORT WAVE LIFTS QUICKLY THROUGH NORTHERN OHIO
LATE SATURDAY. STRENGTHENING SURFACE LOW PRESSURE REFLECTION ALSO
RACES NORTHEAST THROUGH NORTHERN OHIO INTO SOUTHERN ONTARIO
SATURDAY NIGHT. WITH STRONG COLD AIR ADVECTION AND 925 MB FLOW
AROUND 35 KNOTS...INCREASED WIND GUSTS SIGNIFICANTLY FOR SATURDAY
EVENING AS THE COLDER AIR BLOWS IN.
WAS A BIT SLOWER INTRODUCING POPS SATURDAY...BUT GUSTY RAIN
SHOWERS SHOULD STILL WHIP THROUGH LATE SATURDAY INTO EARLY
SATURDAY EVENING BEFORE CHANGING TO SNOW SHOWERS. INCREASED POPS
INTO THE LIKELY CATEGORY FOR LIGHT QPF LATE SATURDAY INTO SATURDAY
EVENING...AND LINGERED LIKELY POPS IN THE UPSLOPE MOUNTAIN ZONES
OVERNIGHT SATURDAY NIGHT.
LINGERING CHANCE POPS LONGER ON SUNDAY INTO SUNDAY EVENING WITH
500 MB TROF AXIS...ESPECIALLY N-E-SE OF PIT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
COLDER WEEKEND WEATHER UNDER A CROSSING UPR TROUGH IS FORECAST...BUT
ONCE AGAIN...MODERATION AND DRY CONDITIONS ARE ANTICIPATED NEXT
WEEK AS HEIGHTS RISE WITH IN ADVANCE OF ANOTHER WRN CONUS LOW. THE
ONLY CAVEAT LOOKS TO BE EARLY WEEK SHORTWAVE ENCROACHMENT AS PER
THE ECMWF SOLUTION WHICH MAY DELAY THE WARM UP AND SPAWN SOME
SHOWERS...CHCS FOR WHICH WERE LEFT IN THE SLIGHT CATEGORY AS PER A
GUIDANCE BLEND.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
VFR CONDITIONS CAN BE EXPECTED EARLY THIS AFTERNOON. A BAND OF
SHOWERS WILL MOVE IN FROM THE WEST LATER THIS AFTERNOON AND
EVENING...PROVIDING SOME RESTRICTIONS IN VISIBILITIES AND CEILINGS.
GUSTY SOUTHERLY WINDS CAN BE EXPECTED THIS AFTERNOON AND EVENING.
A COLD FRONT WILL MOVE THROUGH ON THE BACK EDGE OF THE
SHOWERS...FOLLOWED BY A LOW STRATUS DECK MAY FORM LATE TONIGHT
AND EARLY THURSDAY. THIS DECK WILL GRADUALLY LIFT AND DISSIPATE DURING
THE DAY.
OUTLOOK...THURSDAY THROUGH SUNDAY/...
RESTRICTIONS ARE LIKELY WITH A WEEKEND COLD FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND ADVISORY UNTIL 11 PM EST THIS EVENING FOR MDZ001.
OH...NONE.
PA...WIND ADVISORY UNTIL 11 PM EST THIS EVENING FOR PAZ074-076.
WV...WIND ADVISORY UNTIL 11 PM EST THIS EVENING FOR WVZ510>514.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
845 AM EST WED NOV 18 2015
.SYNOPSIS...
A COLD FRONT WILL BRING SHOWERS LATER TODAY. COOLER TEMPERATURES
ARE IN STORE FOR WEEKS END.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TIGHTENING PRESSURE GRADIENT AND DOWNSLOPING FLOW ARE EXPECTED TO
HELP SUSTAIN WIND GUSTS TODAY AS A COLD FRONT APPROACHES FROM THE
WEST. ACROSS THE RIDGE TOPS AND VALLEYS NEARBY...WIND GUSTS ARE
EXPECTED TO REACH ADVISORY CRITERIA WHILE THE LOW LEVEL JET
ENHANCES IN RESPONSE TO THE STRENGTHENING SURFACE LOW PROGGED TO
SHIFT OVER THE WESTERN GREAT LAKES. HI-RES AND RAP MODEL SOUNDINGS
ALSO INDICATES STRONGER...BUT SHALLOW MIXING AS TEMPERATURES RISE
IN THE AFTERNOON. THEREFORE A WIND ADVISORY WAS ISSUED FOR THE
RIDGE ZONES AND VALLEYS WITHIN.
LOW LEVEL MOISTURE TRANSPORT VIA SOUTHEAST FLOW MAY CAUSE LIGHT
QPF ACROSS THE RIDGES DUE TO OROGRAPHIC LIFT. HAVE MAINTAINED
CHANCE POPS IN THE HIGHER TERRAIN UNTIL THE FRONT APPROACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
THE COLD FRONT WILL SWIFTLY CROSS THE REGION EARLY TONIGHT WITH
WIDESPREAD SHOWERS. STRONG SUBSIDENCE BEHIND THE FRONT IS
EXPECTED TO END THE PRECIPITATION BY THURSDAY MORNING AND KEEP
CONDITIONS DRY THROUGH FRIDAY WITH NEAR SEANONAL LEVELS.
AN AMPLIFYING TROUGH OVER SOUTHERN ONTARIO IS PROGGED TO HELP
INDUCE A SURFACE LOW AND CROSS THE GREAT LAKES ON SATURDAY. A COLD
FRONT IS DEPICTED TO PROGRESS EASTWARD AND HELP SUPPORT SHOWERS
ACROSS THE FORECAST AREA. HAVE MAINTAINED CHANCE POPS AS TIMING OF
THE THE FRONT DIFFERS BETWEEN THE ECMWF AND GFS MODELS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
COLDER WEEKEND WEATHER UNDER A CROSSING UPR TROUGH IS FORECAST...BUT
ONCE AGAIN...MODERATION AND DRY CONDITIONS ARE ANTICIPATED NEXT
WEEK AS HEIGHTS RISE WITH IN ADVANCE OF ANOTHER WRN CONUS LOW. THE
ONLY CAVEAT LOOKS TO BE EARLY WEEK SHORTWAVE ENCROACHMENT AS PER
THE ECMWF SOLUTION WHICH MAY DELAY THE WARM UP AND SPAWN SOME
SHOWERS...CHCS FOR WHICH WERE LEFT IN THE SLIGHT CATEGORY AS PER A
GUIDANCE BLEND.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED TODAY WITH EXCEPTION FOR FKL AND DUJ
WHERE MVFR ST/STRATOCU WL CONT TO STREAM ACRS CNTRL PA. LOW LEVEL
JET ENCROACHMENT INCRSD WIND SHEAR EARLY THIS MRNG...BUT MIXING
HAS ALLEVIATED THAT CONCERN AT THE COST OF GUSTS OF 20 TO 25 KT
THIS MRNG. SFC GUSTS BTN 25 AND 30 KT CAN BE ANTICIPATED AS THAT
PROCESS IMPROVES THIS AFTN.
CONDITION DETERIORATION IS FORECAST THIS EVENING AS A COLD FRONT
PLOUGHS ACRS THE UPR OHIO REGION ACCOMPANIED BY SHWRS.
OUTLOOK...THURSDAY THROUGH SUNDAY/...
RESTRICTIONS ARE LIKELY WITH A WEEKEND COLD FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND ADVISORY UNTIL 11 PM EST THIS EVENING FOR MDZ001.
OH...NONE.
PA...WIND ADVISORY UNTIL 11 PM EST THIS EVENING FOR PAZ074-076.
WV...WIND ADVISORY UNTIL 11 PM EST THIS EVENING FOR WVZ510>514.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
554 AM EST WED NOV 18 2015
.SYNOPSIS...
A COLD FRONT WILL BRING SHOWERS LATER TODAY. COOLER TEMPERATURES
ARE IN STORE FOR WEEKS END.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE PREDAWN UPDATE INCLUDED MINOR CHANGES TO DEW POINT TEMPERATURES.
FORECAST REMAINS ON TRACK AND PREVIOUS DISCUSSION FOLLOWS.
TIGHTENING PRESSURE GRADIENT AND DOWNSLOPING FLOW ARE EXPECTED TO
HELP SUSTAIN WIND GUSTS TODAY AS A COLD FRONT APPROACHES FROM THE
WEST. ACROSS THE RIDGE TOPS AND VALLEYS NEARBY...WIND GUSTS ARE
EXPECTED TO REACH ADVISORY CRITERIA WHILE THE LOW LEVEL JET
ENHANCES IN RESPONSE TO THE STRENGTHENING SURFACE LOW PROGGED TO
SHIFT OVER THE WESTERN GREAT LAKES. HI-RES AND RAP MODEL SOUNDINGS
ALSO INDICATES STRONGER...BUT SHALLOW MIXING AS TEMPERATURES RISE
IN THE AFTERNOON. THEREFORE A WIND ADVISORY WAS ISSUED FOR THE
RIDGE ZONES AND VALLEYS WITHIN.
LOW LEVEL MOISTURE TRANSPORT VIA SOUTHEAST FLOW MAY CAUSE LIGHT
QPF ACROSS THE RIDGES DUE TO OROGRAPHIC LIFT. HAVE MAINTAINED
CHANCE POPS IN THE HIGHER TERRAIN UNTIL THE FRONT APPROACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
THE COLD FRONT WILL SWIFTLY CROSS THE REGION EARLY TONIGHT WITH
WIDESPREAD SHOWERS. STRONG SUBSIDENCE BEHIND THE FRONT IS
EXPECTED TO END THE PRECIPITATION BY THURSDAY MORNING AND KEEP
CONDITIONS DRY THROUGH FRIDAY WITH NEAR SEANONAL LEVELS.
AN AMPLIFYING TROUGH OVER SOUTHERN ONTARIO IS PROGGED TO HELP
INDUCE A SURFACE LOW AND CROSS THE GREAT LAKES ON SATURDAY. A COLD
FRONT IS DEPICTED TO PROGRESS EASTWARD AND HELP SUPPORT SHOWERS
ACROSS THE FORECAST AREA. HAVE MAINTAINED CHANCE POPS AS TIMING OF
THE THE FRONT DIFFERS BETWEEN THE ECMWF AND GFS MODELS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
COLDER WEEKEND WEATHER UNDER A CROSSING UPR TROUGH IS FORECAST...BUT
ONCE AGAIN...MODERATION AND DRY CONDITIONS ARE ANTICIPATED NEXT
WEEK AS HEIGHTS RISE WITH IN ADVANCE OF ANOTHER WRN CONUS LOW. THE
ONLY CAVEAT LOOKS TO BE EARLY WEEK SHORTWAVE ENCROACHMENT AS PER
THE ECMWF SOLUTION WHICH MAY DELAY THE WARM UP AND SPAWN SOME
SHOWERS...CHCS FOR WHICH WERE LEFT IN THE SLIGHT CATEGORY AS PER A
GUIDANCE BLEND.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED TODAY WITH EXCEPTION FOR FKL AND DUJ
WHERE MVFR ST/STRATOCU WL CONT TO STREAM ACRS CNTRL PA. LOW LEVEL
JET ENCROACHMENT INCRSD WIND SHEAR EARLY THIS MRNG...BUT MIXING
HAS ALLEVIATED THAT CONCERN AT THE COST OF GUSTS OF 20 TO 25 KT
THIS MRNG. SFC GUSTS BTN 25 AND 30 KT CAN BE ANTICIPATED AS THAT
PROCESS IMPROVES THIS AFTN.
CONDITION DETERIORATION IS FORECAST THIS EVENING AS A COLD FRONT
PLOUGHS ACRS THE UPR OHIO REGION ACCOMPANIED BY SHWRS.
OUTLOOK...THURSDAY THROUGH SUNDAY/...
RESTRICTIONS ARE LIKELY WITH A WEEKEND COLD FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR MDZ001.
OH...NONE.
PA...WIND ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR PAZ074-076.
WV...WIND ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR WVZ510>514.
&&
$$
15/24
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
506 AM EST WED NOV 18 2015
.SYNOPSIS...
A COLD FRONT WILL BRING SHOWERS LATER TODAY. COOLER TEMPERATURES
ARE IN STORE BY THE END OF THE WEEK AND THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE PREDAWN UPDATE INCLUDS MINOR CHANGES TO DEW POINT
TEMPERATURES. FORECAST REMAINS ON TRACK AND PREVIOUS DISCUSSION
FOLLOWS.
TIGHTENING PRESSURE GRADIENT AND DOWNLSOPING FLOW IS EXPECTED TO
HELP SUSTAIN WIND GUSTS OVERNIGHT AND TODAY AS A COLD FRONT
APPROACHES FROM THE WEST. ACROSS THE RIDGE TOPS AND VALLEYS
NEARBY...WIND GUSTS ARE EXPECTED TO REACH ADVISORY CRITERIA WHILE
THE LOW LEVEL JET ENHANCES IN RESPONSE TO THE STRENGTHENING
SURFACE LOW PROGGED TO SHIFT OVER THE WESTERN GREAT LAKES. HI-RES
AND RAP MODEL SOUNDINGS ALSO INDICATES STRONGER SHALLOW MIXING AS
TEMPERATURES RISE IN THE AFTERNOON. THEREFORE A WIND ADVISORY WAS
ISSUED FOR THE RIDGE ZONES AND VALLEYS WITHIN.
LOW LEVEL MOISTURE TRANSPORT VIA SOUTHEAST FLOW MAY CAUSE LIGHT
QPF ACROSS THE RIDGES DUE TO OROGRAPHIC LIFT. HAVE MAINTAINED
CHANCE POPS IN THE HIGHER TERRAIN UNTIL THE FRONT APPROACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
THE COLD FRONT WILL SWIFTLY CROSS THE REGION EARLY TONIGHT WITH
WIDESPREAD SHOWERS. STRONG SUBSIDENCE BEHIND THE FRONT IS
EXPECTED TO END THE PRECIPITATION BY THURSDAY MORNING AND KEEP
CONDITIONS DRY THROUGH FRIDAY WITH NEAR SEANONAL LEVELS.
AN AMPLIFYING TROUGH OVER SOUTHERN ONTARIO IS PROGGED TO HELP
INDUCE A SURFACE LOW AND CROSS THE GREAT LAKES ON SATURDAY. A COLD
FRONT IS DEPICTED TO PROGRESS EASTWARD AND HELP SUPPORT SHOWERS
ACROSS THE FORECAST AREA. HAVE MAINTAINED CHANCE POPS AS TIMING OF
THE THE FRONT DIFFERS BETWEEN THE ECMWF AND GFS MODELS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
COLDER WEEKEND WEATHER UNDER A CROSSING UPR TROUGH IS FORECAST...BUT
ONCE AGAIN...MODERATION AND DRY CONDITIONS ARE ANTICIPATED NEXT
WEEK AS HEIGHTS RISE WITH IN ADVANCE OF ANOTHER WRN CONUS LOW. THE
ONLY CAVEAT LOOKS TO BE EARLY WEEK SHORTWAVE ENCROACHMENT AS PER
THE ECMWF SOLUTION WHICH MAY DELAY THE WARM UP AND SPAWN SOME
SHOWERS...CHCS FOR WHICH WERE LEFT IN THE SLIGHT CATEGORY AS PER A
GUIDANCE BLEND.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH TODAY WITH EXCEPTION FOR DUJ
WHERE MVFR STRATOCU WL CONT TO STREAM ACRS CNTRL PA. LOW LEVEL
JET ENCROACHMENT HAS INCRSD WIND SHEAR OVR THE REGION...INCLUSION
OF WHICH WAS CONTD UNTIL MIXING IMPROVES LATER THIS MRNG. SFC
GUSTS BTN 25 AND 30 KT CAN BE ANTICIPATED WITH THAT PROCESS.
CONDITION DETERIORATION IS FORECAST THIS EVENING AS A COLD FRONT
PLOUGHS ACRS THE UPR OHIO REGION ACCOMPANIED BY SHWRS.
OUTLOOK...THURSDAY THROUGH SUNDAY/...
RESTRICTIONS ARE LIKELY WITH A WEEKEND COLD FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR MDZ001.
OH...NONE.
PA...WIND ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR PAZ074-076.
WV...WIND ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR WVZ510>514.
&&
$$
24/15
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
315 AM EST WED NOV 18 2015
.SYNOPSIS...
A COLD FRONT WILL BRING SHOWERS LATER TODAY. COOLER TEMPERATURES
ARE IN STORE BY THE END OF THE WEEK AND THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
TIGHTENING PRESSURE GRADIENT AND DOWNLSOPING FLOW IS EXPECTED TO
HELP SUSTAIN WIND GUSTS OVERNIGHT AND TODAY AS A COLD FRONT
APPROACHES FROM THE WEST. ACROSS THE RIDGE TOPS AND VALLEYS
NEARBY...WIND GUSTS ARE EXPECTED TO REACH ADVISORY CRITERIA WHILE
THE LOW LEVEL JET ENHANCES IN RESPONSE TO THE STRENGTHENING
SURFACE LOW PROGGED TO SHIFT OVER THE WESTERN GREAT LAKES. HI-RES
AND RAP MODEL SOUNDINGS ALSO INDICATES STRONGER SHALLOW MIXING AS
TEMPERATURES RISE IN THE AFTERNOON. THEREFORE A WIND ADVISORY WAS
ISSUED FOR THE RIDGE ZONES AND VALLEYS WITHIN.
LOW LEVEL MOISTURE TRANSPORT VIA SOUTHEAST FLOW MAY CAUSE LIGHT
QPF ACROSS THE RIDGES DUE TO OROGRAPHIC LIFT. HAVE MAINTAINED
CHANCE POPS IN THE HIGHER TERRAIN UNTIL THE FRONT APPROACHES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
THE COLD FRONT WILL SWIFTLY CROSS THE REGION EARLY TONIGHT WITH
WIDESPREAD SHOWERS. STRONG SUBSIDENCE BEHIND THE FRONT IS
EXPECTED TO END THE PRECIPITATION BY THURSDAY MORNING AND KEEP
CONDITIONS DRY THROUGH FRIDAY WITH NEAR SEANONAL LEVELS.
AN AMPLIFYING TROUGH OVER SOUTHERN ONTARIO IS PROGGED TO HELP
INDUCE A SURFACE LOW AND CROSS THE GREAT LAKES ON SATURDAY. A COLD
FRONT IS DEPICTED TO PROGRESS EASTWARD AND HELP SUPPORT SHOWERS
ACROSS THE FORECAST AREA. HAVE MAINTAINED CHANCE POPS AS TIMING OF
THE THE FRONT DIFFERS BETWEEN THE ECMWF AND GFS MODELS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
COLDER WEEKEND WEATHER UNDER A CROSSING UPR TROUGH IS FORECAST...BUT
ONCE AGAIN...MODERATION AND DRY CONDITIONS ARE ANTICIPATED NEXT
WEEK AS HEIGHTS RISE WITH IN ADVANCE OF ANOTHER WRN CONUS LOW. THE
ONLY CAVEAT LOOKS TO BE EARLY WEEK SHORTWAVE ENCROACHMENT AS PER
THE ECMWF SOLUTION WHICH MAY DELAY THE WARM UP AND SPAWN SOME
SHOWERS...CHCS FOR WHICH WERE LEFT IN THE SLIGHT CATEGORY AS PER A
GUIDANCE BLEND.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH TODAY WITH EXCEPTION FOR DUJ
WHERE MVFR STRATOCU WL CONT TO STREAM ACRS CNTRL PA. LOW LEVEL
JET ENCROACHMENT HAS INCRSD WIND SHEAR OVR THE REGION...INCLUSION
OF WHICH WAS CONTD UNTIL MIXING IMPROVES LATER THIS MRNG. SFC
GUSTS BTN 25 AND 30 KT CAN BE ANTICIPATED WITH THAT PROCESS.
CONDITION DETERIORATION IS FORECAST THIS EVENING AS A COLD FRONT
PLOUGHS ACRS THE UPR OHIO REGION ACCOMPANIED BY SHWRS.
OUTLOOK...THURSDAY THROUGH SUNDAY/...
RESTRICTIONS ARE LIKELY WITH A WEEKEND COLD FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR MDZ001.
OH...NONE.
PA...WIND ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR PAZ074-076.
WV...WIND ADVISORY FROM 10 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR WVZ510>514.
&&
$$
AREA FORECAST DISCUSSION
NWS GAYLORD MI
323 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 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1203 PM EST WED NOV 18 2015
WIDESPREAD RAIN WILL DIMINISH TO SCATTERED SHOWERS LATER THIS
AFTERNOON AS THE DEEP MOISTURE AXIS PUSHES EAST OF MICHIGAN WITH
THE INITIAL FRONT. THE NEXT WAVE OF SHOWERS WILL ARRIVE ACROSS NW
AND N CENTRAL LWR MICHIGAN OVERNIGHT AS WRAP-AROUND MOISTURE
ARRIVES ON THE BACK SIDE OF THE DEPARTING LOW. PRECIP WILL BECOME
LAKE ENHANCED...WITH SNOW EVENTUALLY MIXING IN WITH THE RAIN
THURSDAY MORNING AS CAA STRENGTHENS. HIGHEST CHANCES OF PRECIP
WILL REMAIN ACROSS NW LWR MICHIGAN (PLN/TVC/MBL) DUE TO LAKE
ENHANCEMENT IN SW LOW LEVEL FLOW. S/SE WINDS WILL CONTINUE TO GUST
TO 25 TO 35 KT THIS AFTERNOON AND EVENING. LLWS WILL AGAIN
DEVELOP OVERNIGHT INTO EARLY THURSDAY AS WINDS SUBSIDE JUST A
BIT...BEFORE STRENGTHENING AGAIN LATER THURSDAY MORNING AS STRONG
CAA COMMENCES IN THE WAKE OF THE DEPARTING LOW AND COLD FRONT.
OVERALL CONDITIONS WILL REMAIN VFR/HIGH MVFR THRU THE TAF FORECAST
PERIOD DESPITE ALL OF THE RAIN AND WIND.
&&
.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 FROM 7 PM THIS EVENING TO 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...MLR
MARINE...MLR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
417 AM EST WED NOV 18 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...(THURSDAY THROUGH TUESDAY)
ISSUED AT 417 AM EST WED NOV 18 2015
NAM SHOWS A DEEP AND BROAD 500 MB TROUGH OVER THE CENTRAL U.S. 12Z
THU WITH THE TROUGH AXIS MOVING THROUGH THE UPPER GREAT LAKES ON
THU. MORE TROUGHING THEN MOVES IN FOR FRI NIGHT INTO THE AREA. NAM
BRINGS IN SOME 850-500 MB Q-VECTOR CONVERGENCE AND DEEPER MOISTURE
INTO THE AREA FRI NIGHT. GFS AND ECMWF ARE A BIT FURTHER SOUTHEAST
WITH THIS NEXT SYSTEM FOR FRI NIGHT AND WILL GO MORE WITH THAT
SCENARIO WITH THE SYSTEM.
DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST. DID HOIST UP A
HIGH WIND WATCH FOR THE KEWEENAW PENINSULA FOR THU AFTERNOON AND
EVENING WITH A FAVORED SOUTHWEST WIND DIRECTION AND TIGHT GRADIENT
PRODUCING THE HIGH WIND GUSTS UP TO ALMOST 60 MPH. THE COLD AIR
COMES IN ON THU AND PCPN WILL QUICKLY TRANSITION FOR RAIN TO SNOW
ACROSS THE CWA. COULD SEE UP TO 3 INCHES OF SNOW FOR THU NIGHT IN
THE KEWEENAW PENINSULA WITH WEST WINDS AND HAVE SOME BLOWING SNOW IN
THAT AREA AS WELL WITH THE STRONG WINDS. OVERALL...DID NOT MAKE TOO
MANY CHANGES TO THE GOING FORECAST.
IN THE EXTENDED...GFS AND ECMWF SHOW A DEEP 500 MB TROUGH OVER THE
NORTHERN PLAINS AND UPPER GREAT LAKES REGION 12Z SAT THAT HEADS EAST
INTO THE LOWER GREAT LAKES 12Z SUN WITH COLD AIR ALOFT WITH 850 MB
TEMPERATURES DOWN TO -13C. A SHORTWAVE DIGS INTO THE UPPER GREAT
LAKES REGION 12Z MON WITH THE TROUGH AXIS OVER THE LOWER GREAT LAKES
BY 12Z TUE. TEMPERATURES LOOK TO STAY BELOW NORMAL FOR THIS FORECAST
PERIOD WITH PCPN STAYING AS SNOW AS IT STAYS COLD ENOUGH FOR IT.
LAKE EFFECT PCPN WILL CONTINUE INTO SUNDAY AND THEN WILL START UP
AGAIN MON NIGHT INTO TUE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1152 PM EST TUE NOV 17 2015
SHOWERS WILL CONTINUE TO STREAM NORTH INTO THE UPPER GREAT LAKES
THRU THIS MRONING...AFFECTING KSAW MOST PERSISTENTLY. KSAW WILL
HAVE THE LOWEST CONDITIONS DUE TO AN UPSLOPE SOUTHERLY FLOW. IFR
CONDITIONS SHOULD GENERALLY PREVAIL WITH SOME PERIODS OF LOW MVFR
AND PERHAPS EVEN LIFR. WITH WINDS HAVING MORE OF A DOWNSLOPE
COMPONENT AND WITH MAIN PCPN AREA JUST TO THE E...KIWD/KCMX SHOULD
SEE MVFR CONDITIONS PREVAIL INTO THE MORNING HRS. AT ALL
TERMINALS...EXPECT LLWS THRU THE NIGHT WITH LOW-LEVEL JET OF 40-
55KT OVER THE AREA PER LATEST KMQT VAD WIND PROFILE AND MODEL
GUIDANCE. PASSAGE OF OCCLUDED FRONT THIS AFTN WILL BRING
IMPROVEMENT TO VFR AT KIWD/KCMX IN THE MID TO LATE AFTN. AT
KSAW...IMPROVEMENT TO MVFR WILL OCCUR TOWARD EVENING. WINDS TODAY
WILL BE GUSTY TO 20-30KT AT KIWD/KCMX AND TO NEAR 35KT AT KSAW.
&&
.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...
HIGH WIND WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING
FOR MIZ001-003.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST FRIDAY FOR LSZ264-266-267.
GALE WARNING FROM 7 PM EST /6 PM CST/ THIS EVENING TO 4 PM EST
/3 PM CST/ FRIDAY FOR LSZ162-263.
GALE WARNING FROM 7 PM THIS EVENING TO 7 PM EST FRIDAY FOR
LSZ265.
GALE WARNING UNTIL 5 AM EST THURSDAY FOR LSZ251.
GALE WARNING FROM 7 PM THIS EVENING TO 5 PM EST FRIDAY FOR
LSZ244-245.
GALE WARNING FROM 7 AM THURSDAY TO 7 AM EST FRIDAY FOR LSZ246-
247.
GALE WARNING FROM 1 AM EST /MIDNIGHT CST/ THURSDAY TO 5 PM EST
/4 PM CST/ FRIDAY FOR LSZ240>243.
LAKE MICHIGAN...
GALE WARNING UNTIL 5 AM EST FRIDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...KC
LONG TERM...07
AVIATION...ROLFSON
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1153 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 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1152 PM EST TUE NOV 17 2015
SHOWERS WILL CONTINUE TO STREAM NORTH INTO THE UPPER GREAT LAKES
THRU THIS MRONING...AFFECTING KSAW MOST PERSISTENTLY. KSAW WILL
HAVE THE LOWEST CONDITIONS DUE TO AN UPSLOPE SOUTHERLY FLOW. IFR
CONDITIONS SHOULD GENERALLY PREVAIL WITH SOME PERIODS OF LOW MVFR
AND PERHAPS EVEN LIFR. WITH WINDS HAVING MORE OF A DOWNSLOPE
COMPONENT AND WITH MAIN PCPN AREA JUST TO THE E...KIWD/KCMX SHOULD
SEE MVFR CONDITIONS PREVAIL INTO THE MORNING HRS. AT ALL
TERMINALS...EXPECT LLWS THRU THE NIGHT WITH LOW-LEVEL JET OF 40-
55KT OVER THE AREA PER LATEST KMQT VAD WIND PROFILE AND MODEL
GUIDANCE. PASSAGE OF OCCLUDED FRONT THIS AFTN WILL BRING
IMPROVEMENT TO VFR AT KIWD/KCMX IN THE MID TO LATE AFTN. AT
KSAW...IMPROVEMENT TO MVFR WILL OCCUR TOWARD EVENING. WINDS TODAY
WILL BE GUSTY TO 20-30KT AT KIWD/KCMX AND TO NEAR 35KT AT KSAW.
&&
.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 UNTIL 7 PM EST WEDNESDAY FOR LSZ264-266-267.
GALE WARNING UNTIL 2 AM EST WEDNESDAY FOR LSZ244-245.
GALE WARNING UNTIL 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...ROLFSON
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1141 PM EST TUE NOV 17 2015
.UPDATE...
ISSUED AT 953 PM EST TUE NOV 17 2015
EVERYTHING PLAYING OUT QUITE WELL ASIDE FROM SOME TWEAKING HERE
AND THERE. WINDS GUSTING A LITTLE STRONGER IN SPOTS AND AS USUAL
THE CHANCES FOR SEEING RAIN/TIMING/LOCATION ALL SEEING SOME MINOR
ADJUSTMENTS. STILL SEE WING OF BETTER CORE OF WARM/MOIST
ADVECTION AND STRONGER FORCING WORKING NORTHWARD THROUGH 06-07Z
THROUGH EASTERN UPPER...WHILE LINGERING CHANCES FOR RAIN WILL
RESIDE ALONG THE NW LOWER COUNTIES AND WESTERN SECTIONS OF EASTERN
UPPER. DEEPER DRIER AIR STILL SLATED TO SWING UP ACROSS THE REST
OF THE CWA...SEEN ON LATEST SATELLITE IMAGERY WITH JUST SOME MID
AND HIGH LEVEL CLOUD....ESPECIALLY ACROSS SW LOWER THROUGH
INDIANA.
DEEPER MOISTURE SLOWLY WORKS IT`S WAY INTO THE REGION TOMORROW
MORNING THROUGH AFTERNOON FROM WEST TO EAST...WITH PERIODIC
RAIN/LIGHT RAIN EXPECTED.
THE MOST INTERESTING THING TO WATCH WILL BE HOW MUCH OF THE
STRONG WIND THAT IS CURRENTLY OCCURRING JUST ABOVE THE SFC...WILL
MIX DOWN WITH/BEHIND THE OCCLUDED FRONT FOR LATE TOMORROW
AFTERNOON ACROSS MANISTEE/GTV BAY AREA. SOME DATA SUGGEST WIND
ADVISORIES COULD BE MET...WHILE OTHER DATA FALLS SHORT. WILL
OBVIOUSLY BE TAKING A LOOK AT NEW DATA OVER THE NEXT SEVERAL
HOURS.
&&
.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 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1135 PM EST TUE NOV 17 2015
...STRONG LLWS....
WAA REGIME OVERHEAD CONTINUES WHILE THE PRESSURE GRADIENT
INCREASES. MINIMAL MIXING TO THE SFC WITH INCREASING WINDS ALOFT
CONTINUES TO STRENGTHEN LLWS FOR THE REST OF THE NIGHT AND THROUGH
MUCH OF TOMORROW. AN OCCLUDED FRONT ARRIVES LATE WEDNESDAY
AFTERNOON WHICH WILL HELP MIX DOWN THOSE STRONGER WINDS ALOFT.
CONFIDENCE IS NOT TOO HIGH...FORECAST HAS ROUGHLY 34-38KT
GUSTS...BUT WOULD LEAN MORE TOWARD SLIGHTLY HIGHER GUSTS IF
ANYTHING. THESE STRONGER GUSTS NOT EXPECTED AT APN UNTIL EARLY
WEDNESDAY EVENING...BUT OVERALL GUSTINESS WILL BE DROPPING OFF A
BIT THROUGH WEDNESDAY NIGHT.
THE AREA OF ENHANCED WAA/STRONGER FORCING RESULTING IN A BAND OF
RAIN HAS PRETTY MUCH CLEARED THE AREA...WHILE DEEPER DRIER AIR
WILL SWEEP IN OVER ALL AIRPORTS FOR THE REMAINDER OF THE NIGHT AND
INTO THE DAYLIGHT HOURS OF WEDNESDAY. THAT SAID...THERE REMAINS A
SMALLISH CHANCE FOR SOME SPOTTIER SHOWERS AT THE NW LOWER
AIRPORTS. SOLID VFR CONDITIONS INTO TOMORROW MORNING. ANOTHER
BAND/SWATH OF RAIN ARRIVES AHEAD OF AN OCCLUDED FRONT THROUGH
MUCH OF THE DAY...WITH MVFR CIGS A BETTER CHANCE. VSBYS NOT
EXPECTED TO TAKE MUCH OF A HIT...AT LEAST FROM A PREVAILING
CONDITION PERSPECTIVE.
&&
.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.
&&
$$
UPDATE...DICKSON
NEAR TERM...MLR
SHORT TERM...MSB
LONG TERM...GILLEN
AVIATION...DICKSON
MARINE...MLR
AREA FORECAST DISCUSSION
NWS BILLINGS MT
942 AM MST WED NOV 18 2015
.UPDATE...
NO LARGE CHANGES TO THE FORECAST ASIDE FROM CANCELLING THE HIGH
WIND WARNING OUT NEAR LIVINGSTON...THE PARADISE VALLEY...THE
BEARTOOTH FOOTHILLS...AND ALONG HIGHWAY 191 FROM BIG TIMBER TO
JUDITH GAP.
COLD FRONT HAS PUSHED ENTIRELY THROUGH THE FORECAST AREA AS OF 9
AM AND IN ITS WAKE STRONG NORTHWESTERLY WINDS HAVE FILTERED INTO
THE FORECAST REGION. PRESSURE RISES HAVE LESSENED THE GRADIENT
OVER WESTERN PORTIONS OF THE FORECAST AREA NEAR LIVINGSTON SO GAP
FLOW CONDITIONS HAVE SUBISDED. HOWEVER ELEVATED WINDS WILL
CONTINUE THERE AS COLD AIR ADVECTION CONTINUES THROUGH THE
AFTERNOON. FURTHER EAST STRONG WINDS ALOFT NEAR THE SURFACE AS
SUBSIDENCE ALONG THE WESTERN FLANK OF THIS SHORTWAVE AXIS HELPS
SOME STRONGER WINDS MOVE TO THE NEAR SURFACE LAYERS. BELEIVE THE
STRONGEST WINDS HAVE ALREADY OCCURED IN OUR ENTIRE FORECAST AREA
BUT CANNOT RULE OUT HIGH WIND CRITERIA GUSTS OVER THE NEXT 6
HOURS....ESPECIALLY IN OUR 4 EASTERN COUNTIES. DOBBS
&&
.SHORT TERM...VALID FOR TDY AND THU...
DID NOT CHANGE MUCH FOR THE GOING FORECAST FOR TODAY AND TONIGHT
WHERE THE BIGGEST CONCERN WILL BE THE WINDS. THE MODELS WERE IN
GOOD AGREEMENT WITH THIS EVENT...WITH THE GFS HANDLING WINDS ALOFT
A LITTLE BETTER THAN THE WRF.
A STRONG 140+ KT JET HAS PUSHED INTO THE PACIFIC NW ALONG WITH A
POWERFUL SHORTWAVE. EARLIER WATER VAPOR IMAGERY WAS SHOWING AN
AREA OF STRONG SUBSIDENCE BEHIND THE WAVE OVER WA...BUT THIS AREA
HAS DISSIPATED IN MORE RECENT IMAGES. THERE WAS A STRONG AREA OF
SUBSIDENCE ON WATER VAPOR IN THE LEE OF THE MOUNTAINS OVER MT
WHERE KLVM AND NYE MET HIGH WIND WARNING CRITERIA EARLIER IN THE
NIGHT WITH A 24 MB PRESSURE DIFFERENCE BETWEEN KLWT AND KIDA. THE
SYSTEM/S COLD FRONT HAD JUST MOVED THROUGH KTFX AT 09Z. BEHIND THE
FRONT...PRESSURE RISES WERE ON THE ORDER OF 2-3 MB/HR...WHICH WAS
VERY STRONG.
MODELS BRING THE JET SE OVER THE AREA TODAY WHILE WEAKENING. THE
JET WILL PROVIDE SOME WEAK DIVERGENCE THROUGH THE DAY. THE
SHORTWAVE WAS FORECAST TO MOVE THROUGH THE AREA BETWEEN 11Z AND
18Z. THE HRRR SHOWED THE COLD FRONT WAS FORECAST TO MOVE THROUGH
THE FORECAST AREA FROM 10Z TO 14Z...PASSING THROUGH KBIL AROUND
12Z. A FAST-MOVING BAND OF RAIN/SNOW WILL ACCOMPANY THE FRONT
ALONG WITH WIND GUSTS IN THE 50S AND 60S. HAVE ADJUSTED THE WIND
DIRECTION THIS MORNING TO MAKE IT MORE-POST FRONTAL...AND ADJUSTED
THE POPS. THE RAP AND HRRR SHOWED THE PRESSURE RISES INCREASING TO
5 TO 7 MB/HR OVER THE CENTRAL AND WESTERN ZONES WITH THE FRONTAL
PASSAGE. THE GFS HAD PRESSURE RISES OVER A MB/HR AT 18Z THEN
DECREASED THEM THROUGH THE AFTERNOON. STRONG Q-VECTOR CONVERGENCE
MAY HELP OFFSET THE STRONG PRESSURE RISES AROUND 12Z...BEFORE
STRONG DIVERGENCE MOVES IN BY 18Z.
SO THE HIGH WIND WARNINGS WERE IN GOOD SHAPE. WILL BE INTERESTING
TO SEE HOW THE MORNING LIFT COMPETES WITH PRESSURE RISES AND STEEP
LAPSE RATES. REGARDLESS...THE STRONGEST WIND GUSTS SHOULD BE THIS
MORNING. MODELS DECREASED THE WINDS ALOFT GRADUALLY THROUGH THE
AFTERNOON...BUT IT WILL STILL BE WINDY. SOME HIGH WIND WARNINGS
MAY BE ABLE TO BE CANCELLED EARLY...ESPECIALLY IN THE E...WHERE
MODEL SOUNDINGS DID NOT LOOK AS FAVORABLE FOR HIGH WINDS TONIGHT.
KEPT A CHANCE OF PRECIPITATION OVER THE MOUNTAINS TONIGHT WHEN
PACIFIC MOISTURE RESURGES INTO THE WESTERN ZONES. ARTHUR
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
NORTHWEST FLOW ALOFT LEFT BEHIND FROM THE DYNAMIC WAVE OF TODAY.
A FAST MOVING SHORTWAVE WILL DROP INTO THE WESTERN ZONES THURSDAY
AFTERNOON AND THURSDAY NIGHT. AHEAD OF THIS WAVE...MOISTURE WILL
BEGIN TO STREAM INTO THE MOUNTAINS FOR LIKELY SNOW. THE MODELS
CONTINUE TO BE DIFFERENT WITH THIS WAVE...AND DRAMATICALLY SO IN
REGARDS TO QPF. THE ECMWF WAS FARTHER WEST AND STRONGER WITH THE
ENERGY AND THEREFORE HAS QUITE A BIT MORE QPF BEING PRODUCED
THURSDAY AND THURSDAY NIGHT. THE GFS WAS MUCH WEAKER AND FARTHER
EAST WITH THE WAVE AND DRIER DUE TO MUCH LESS UPSLOPE. CONFIDENCE
NOT HIGH DUE TO MODEL DISAGREEMENT. HARD TO IGNORE THE CONSISTENCY
OF THE ECMWF AND HAVE RAISED POPS BACK UP INTO THE SCATTERED
CATEGORY FOR WESTERN AND CENTRAL ZONES. THE MOST LIKELY TIME FOR
SNOWFALL WILL BE THURSDAY NIGHT. IF THE ECMWF IS RIGHT...THERE
COULD BE CLOSE TO ADVISORY TYPE OF SNOW AMOUNTS OVER THE WEST. DO
NOT HAVE CONFIDENCE TO GO TOO AGGRESSIVE WITH THIS SYSTEM...DUE TO
MODEL INCONSISTENCIES. THE MOUNTAINS SHOULD PICK UP ACCUMULATING
SNOW WITH AMOUNTS AROUND 3-6 INCHES. TWH
WILL LEAVE IN LINGERING SNOW SHOWERS FRIDAY AS THE THURSDAY NIGHT
WAVE EXISTS TO THE SOUTHEAST. FRIDAY SHOULD BE CHILLY WITH A
1030MB HIGH SHIFTING OVER THE FORECAST AREA. MODELS DISAGREE WITH
ANOTHER WAVE SET TO MOVE DOWN IN NORTHWEST FLOW FOR SATURDAY. THE
ECMWF WAS STRONGER...BUT DUE TO THE LACK OF MOISTURE...BOTH MODELS
ARE DRY. WILL LEAVE THE DRY FORECAST IN PLACE THROUGH THE WEEKEND.
FLOW VEERS TO THE WEST EARLY NEXT WEEK AS A TROUGH TRIES TO DEEPEN
ALONG THE WEST COAST. THIS WILL LEAD TO WARMING DOWNSLOPE FLOW
WHICH WILL KEEP TEMPERATURES AT OR SLIGHTLY ABOVE CLIMATOLOGICAL
AVERAGES. PUSHED THE CHANCE OF SNOW SHOWERS INTO THE WEST...MAINLY
THE HIGH COUNTRY...FOR MONDAY AND TUESDAY. TWH
&&
.AVIATION...
EXPECT EVERY WINDY CONDITIONS TO CONTINUE INTO THIS AFTERNOON
FROM BILLINGS AND SHERIDAN EAST. WINDS GUST 60+ KNOTS ARE POSSIBLE
ESPECIALLY AROUND SHERIDAN. SCATTERED SNOW SHOWERS WILL CONTINUE
EAST OF BILLINGS AND COULD REDUCE CONDITIONS TO IFR BRIEFLY THIS
MORNING. REIMER
&&
.PRELIMINARY POINT TEMP/POPS...
TDY THU FRI SAT SUN MON TUE
-------------------------------------------------------
BIL 043 025/039 021/033 018/038 027/048 028/044 027/043
3/W 11/E 43/J 10/B 00/N 11/B 11/B
LVM 038 027/035 020/032 019/039 026/043 028/044 028/043
3/J 13/J 53/J 10/N 01/N 12/W 22/W
HDN 044 022/039 020/033 015/039 021/049 024/046 023/045
3/W 11/E 44/J 10/B 00/U 11/B 10/B
MLS 042 020/037 016/033 014/038 017/048 022/045 022/042
4/W 01/B 23/J 10/B 00/B 00/B 00/B
4BQ 042 020/037 017/032 012/038 017/049 022/048 022/048
4/W 11/B 33/J 10/U 00/U 00/B 00/B
BHK 041 017/033 013/030 012/034 016/045 022/044 021/041
3/W 00/N 22/J 20/B 00/B 10/B 00/B
SHR 042 020/038 019/032 011/038 015/050 019/045 021/047
3/W 11/B 34/J 10/U 00/U 11/U 00/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...HIGH WIND WARNING IN EFFECT UNTIL 5 PM MST THIS AFTERNOON FOR
ZONES 29-30-34-35-38-39-42-57.
HIGH WIND WARNING IN EFFECT UNTIL 11 PM MST THIS EVENING FOR
ZONES 31-32-36-58.
HIGH WIND WARNING IN EFFECT UNTIL 5 AM MST THURSDAY FOR ZONES
33-37.
WY...HIGH WIND WARNING IN EFFECT UNTIL 5 PM MST THIS AFTERNOON FOR
ZONES 98-99.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
246 AM MST WED NOV 18 2015
.SHORT TERM...VALID FOR TDY AND THU...
DID NOT CHANGE MUCH FOR THE GOING FORECAST FOR TODAY AND TONIGHT
WHERE THE BIGGEST CONCERN WILL BE THE WINDS. THE MODELS WERE IN
GOOD AGREEMENT WITH THIS EVENT...WITH THE GFS HANDLING WINDS ALOFT
A LITTLE BETTER THAN THE WRF.
A STRONG 140+ KT JET HAS PUSHED INTO THE PACIFIC NW ALONG WITH A
POWERFUL SHORTWAVE. EARLIER WATER VAPOR IMAGERY WAS SHOWING AN
AREA OF STRONG SUBSIDENCE BEHIND THE WAVE OVER WA...BUT THIS AREA
HAS DISSIPATED IN MORE RECENT IMAGES. THERE WAS A STRONG AREA OF
SUBSIDENCE ON WATER VAPOR IN THE LEE OF THE MOUNTAINS OVER MT
WHERE KLVM AND NYE MET HIGH WIND WARNING CRITERIA EARLIER IN THE
NIGHT WITH A 24 MB PRESSURE DIFFERENCE BETWEEN KLWT AND KIDA. THE
SYSTEM/S COLD FRONT HAD JUST MOVED THROUGH KTFX AT 09Z. BEHIND THE
FRONT...PRESSURE RISES WERE ON THE ORDER OF 2-3 MB/HR...WHICH WAS
VERY STRONG.
MODELS BRING THE JET SE OVER THE AREA TODAY WHILE WEAKENING. THE
JET WILL PROVIDE SOME WEAK DIVERGENCE THROUGH THE DAY. THE
SHORTWAVE WAS FORECAST TO MOVE THROUGH THE AREA BETWEEN 11Z AND
18Z. THE HRRR SHOWED THE COLD FRONT WAS FORECAST TO MOVE THROUGH
THE FORECAST AREA FROM 10Z TO 14Z...PASSING THROUGH KBIL AROUND
12Z. A FAST-MOVING BAND OF RAIN/SNOW WILL ACCOMPANY THE FRONT
ALONG WITH WIND GUSTS IN THE 50S AND 60S. HAVE ADJUSTED THE WIND
DIRECTION THIS MORNING TO MAKE IT MORE-POST FRONTAL...AND ADJUSTED
THE POPS. THE RAP AND HRRR SHOWED THE PRESSURE RISES INCREASING TO
5 TO 7 MB/HR OVER THE CENTRAL AND WESTERN ZONES WITH THE FRONTAL
PASSAGE. THE GFS HAD PRESSURE RISES OVER A MB/HR AT 18Z THEN
DECREASED THEM THROUGH THE AFTERNOON. STRONG Q-VECTOR CONVERGENCE
MAY HELP OFFSET THE STRONG PRESSURE RISES AROUND 12Z...BEFORE
STRONG DIVERGENCE MOVES IN BY 18Z.
SO THE HIGH WIND WARNINGS WERE IN GOOD SHAPE. WILL BE INTERESTING
TO SEE HOW THE MORNING LIFT COMPETES WITH PRESSURE RISES AND STEEP
LAPSE RATES. REGARDLESS...THE STRONGEST WIND GUSTS SHOULD BE THIS
MORNING. MODELS DECREASED THE WINDS ALOFT GRADUALLY THROUGH THE
AFTERNOON...BUT IT WILL STILL BE WINDY. SOME HIGH WIND WARNINGS
MAY BE ABLE TO BE CANCELLED EARLY...ESPECIALLY IN THE E...WHERE
MODEL SOUNDINGS DID NOT LOOK AS FAVORABLE FOR HIGH WINDS TONIGHT.
KEPT A CHANCE OF PRECIPITATION OVER THE MOUNTAINS TONIGHT WHEN
PACIFIC MOISTURE RESURGES INTO THE WESTERN ZONES. ARTHUR
NORTHWEST FLOW ALOFT LEFT BEHIND FROM THE DYNAMIC WAVE OF TODAY.
A FAST MOVING SHORTWAVE WILL DROP INTO THE WESTERN ZONES THURSDAY
AFTERNOON AND THURSDAY NIGHT. AHEAD OF THIS WAVE...MOISTURE WILL
BEGIN TO STREAM INTO THE MOUNTAINS FOR LIKELY SNOW. THE MODELS
CONTINUE TO BE DIFFERENT WITH THIS WAVE...AND DRAMATICALLY SO IN
REGARDS TO QPF. THE ECMWF WAS FARTHER WEST AND STRONGER WITH THE
ENERGY AND THEREFORE HAS QUITE A BIT MORE QPF BEING PRODUCED
THURSDAY AND THURSDAY NIGHT. THE GFS WAS MUCH WEAKER AND FARTHER
EAST WITH THE WAVE AND DRIER DUE TO MUCH LESS UPSLOPE. CONFIDENCE
NOT HIGH DUE TO MODEL DISAGREEMENT. HARD TO IGNORE THE CONSISTENCY
OF THE ECMWF AND HAVE RAISED POPS BACK UP INTO THE SCATTERED
CATEGORY FOR WESTERN AND CENTRAL ZONES. THE MOST LIKELY TIME FOR
SNOWFALL WILL BE THURSDAY NIGHT. IF THE ECMWF IS RIGHT...THERE
COULD BE CLOSE TO ADVISORY TYPE OF SNOW AMOUNTS OVER THE WEST. DO
NOT HAVE CONFIDENCE TO GO TOO AGGRESSIVE WITH THIS SYSTEM...DUE TO
MODEL INCONSISTENCIES. THE MOUNTAINS SHOULD PICK UP ACCUMULATING
SNOW WITH AMOUNTS AROUND 3-6 INCHES. TWH
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
WILL LEAVE IN LINGERING SNOW SHOWERS FRIDAY AS THE THURSDAY NIGHT
WAVE EXISTS TO THE SOUTHEAST. FRIDAY SHOULD BE CHILLY WITH A
1030MB HIGH SHIFTING OVER THE FORECAST AREA. MODELS DISAGREE WITH
ANOTHER WAVE SET TO MOVE DOWN IN NORTHWEST FLOW FOR SATURDAY. THE
ECMWF WAS STRONGER...BUT DUE TO THE LACK OF MOISTURE...BOTH MODELS
ARE DRY. WILL LEAVE THE DRY FORECAST IN PLACE THROUGH THE WEEKEND.
FLOW VEERS TO THE WEST EARLY NEXT WEEK AS A TROUGH TRIES TO DEEPEN
ALONG THE WEST COAST. THIS WILL LEAD TO WARMING DOWNSLOPE FLOW
WHICH WILL KEEP TEMPERATURES AT OR SLIGHTLY ABOVE CLIMATOLOGICAL
AVERAGES. PUSHED THE CHANCE OF SNOW SHOWERS INTO THE WEST...MAINLY
THE HIGH COUNTRY...FOR MONDAY AND TUESDAY. TWH
&&
.AVIATION...
TODAY WILL BE WROUGHT WITH WIND. GUSTS TO 68 KTS HAVE ALREADY
OCCURRED AT KLVM OVERNIGHT AND THESE WIND GUSTS WILL CONTINUE THIS
MORNING. WINDS WILL TURN TO THE WEST AT KLVM BY LATE MORNING WITH
THE STRONGEST SUBSIDING A BIT...BUT STILL EXPECT GUSTS TO 50 KTS.
THE STRONGER WINDS WILL SPREAD INTO KBIL/KSHR/KMLS 13-15Z WITH
GUSTS TO 50 KTS EXPECTED. WINDS WILL STAY STRONG MOST OF THE DAY
WITH A GRADUAL TAPERING OFF TREND FROM WEST TO EAST. A LINE OF
SHOWERS IS ALSO EXPECTED AHEAD OF THE COLD FRONT BRINGING THE
WIND. THE SHOWERS SHOULD WEAKEN AS THEY MOVE ACROSS THE AREA BUT
STILL WILL LOWER CEILINGS TO LOCAL MVFR WITH A BURST OF RAIN/SNOW
AS THEY MOVE THROUGH. THESE SHOWERS COULD ALSO ENHANCE THE WINDS
AHEAD OF THE COLD FRONT AND MAKE THEM A LITTLE STRONGER. EXPECTED
TIME OF THE SHOWERS IN KBIL WOULD BE AROUND 12Z. TWH &&
.PRELIMINARY POINT TEMP/POPS...
TDY THU FRI SAT SUN MON TUE
-------------------------------------------------------
BIL 043 025/039 021/033 018/038 027/048 028/044 027/043
2/W 11/E 43/J 10/B 00/N 11/B 11/B
LVM 038 027/035 020/032 019/039 026/043 028/044 028/043
2/W 13/J 53/J 10/N 01/N 12/W 22/W
HDN 044 022/039 020/033 015/039 021/049 024/046 023/045
3/J 11/E 44/J 10/B 00/U 11/B 10/B
MLS 042 020/037 016/033 014/038 017/048 022/045 022/042
2/W 01/B 23/J 10/B 00/B 00/B 00/B
4BQ 042 020/037 017/032 012/038 017/049 022/048 022/048
3/W 11/B 33/J 10/U 00/U 00/B 00/B
BHK 041 017/033 013/030 012/034 016/045 022/044 021/041
2/W 00/N 22/J 20/B 00/B 10/B 00/B
SHR 042 020/038 019/032 011/038 015/050 019/045 021/047
2/J 11/B 34/J 10/U 00/U 11/U 00/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...HIGH WIND WARNING IN EFFECT UNTIL 5 PM MST THIS AFTERNOON FOR
ZONES 28>30-34-35-38>42-56-57-63>66.
HIGH WIND WARNING IN EFFECT UNTIL 11 PM MST THIS EVENING FOR
ZONES 31-32-36-58.
HIGH WIND WARNING IN EFFECT UNTIL 5 AM MST THURSDAY FOR ZONES
33-37.
WY...HIGH WIND WARNING IN EFFECT UNTIL 5 PM MST THIS AFTERNOON FOR
ZONES 98-99.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS OMAHA/VALLEY NE
725 AM CST WED NOV 18 2015
.UPDATE...
ISSUED AT 725 AM CST WED NOV 18 2015
SENT OUT A QUICK UPDATE. WEB CAM NEAR YORK SHOWING A BIT OF SNOW
HAD ACCUMULATED THERE. BAND OF HIGHEST RADAR ECHOES FROM AROUND
COLUMBUS TO FAIRBURY MAY HAVE SNOW WITH VERY MINOR ACCUMULATIONS
THE NEXT FEW HOURS AS IT TRACKS EAST...THEN SHOULD GO BACK TO A
MIX. ALSO MADE A FEW MINOR TIMING ADJUSTMENTS FOR PCPN TODAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 342 AM CST WED NOV 18 2015
...POTENTIAL FOR FIRST WIDESPREAD SNOW OF THE SEASON FRIDAY...
FORECAST CONCERNS IN THE SHORT TERM WILL CONTINUE TO BE
PRECIPITATION WITH THE LARGE WEATHER SYSTEM TODAY AS LIFTS
NORTHEAST OUT OF THE AREA...RAIN OR A RAIN/SNOW MIX AND POTENTIAL
FOR WIND HEADLINES...ATTENTION THEN TURNS TO THE POTENTIAL FOR A
SWATH OF SNOW ACROSS PARTS OF SD/NE/IA/WI AND COLDER TEMPERATURES.
AT 0930Z...THE REGIONAL WSR-88D MOSAIC RADAR SHOWED A SPREAD OUT
PRECIPITATION PATTERN WITH RAIN WRAPPING AROUND THE ELONGATED UPPER
LOW PRESSURE SYSTEM FROM IOWA...TOWARD MINNESOTA AND SOUTH DAKOTA
AND BACK TOWARD CENTRAL NEBRASKA. SHOWERS ARE BEGINNING TO RE-
DEVELOP IN THE VICINITY OF THE H5 LOW CENTER OVER NORTHEAST
KANSAS. THUNDERSTORMS WERE NOTED WITH THE ELEVATED INSTABILITY
OVER MINNESOTA AND A MIX OF RAIN/SNOW AND SNOW TOWARD ONEILL AND
KEARNEY.
THE NEXT FEATURE OF INTEREST IS A STRONG SHORTWAVE OVER MONTANA
THAT WILL DIVE SOUTHEAST IN RESPONSE TO A 110KT UPR LEVEL JET.
IMPRESSIVE WINDS WERE NOTED OVERNIGHT WITH MANY STATIONS SUSTAINED
AT 40KTS GUSTING TO OVER 50KTS.
THE DETERMINISTIC MODELS ARE IN GOOD AGREEMENT WITH THE TRACK OF THE
H5 LOW WITH 200M HEIGHT FALLS...OVER NORTHEAST KANSAS (A LITTLE
SOUTHEAST OF WHERE IT WAS FORECAST TO BE YESTERDAY)...LIFTS NORTHEAST
INTO IOWA BY 18Z AND THE U.P. BY 00Z. THE LARGE AREA OF SURFACE
LOW PRESSURE WITH LOCAL MINIMUMS IN KANSAS AND WESTERN
IOWA...WILL CONSOLIDATE OVER MINNESOTA DURING THE DAY.
MEANWHILE...THE SHORTWAVE RACES SOUTHEAST TOWARD NEBRASKA WITH
WARMING H85 TEMPERATURES AHEAD OF IT.
COMPLEX PRECIPITATION FORECAST WITH ONE SYSTEM EXITING THE
AREA...WHILE THE NEXT RACES IN BEHIND IT OVER THE NEXT 12HRS. HAVE
THREE AREAS OF PRECIPITATION...THE AREA CLOSER TO THE SURFACE
FRONT...THE DEFORMATION BAND...AND THE PRECIPITATION ASSOCIATED
WITH THE SHORTWAVE. THERE MAY BE A MIX OF RAIN OR SNOW WITH THE
DEFORMATION BAND AND THERE COULD BE SOME SNOW MIXED IN AS THE
DEPTH OF THE COLD AIR INCREASES OR AREAS WHERE THERE IS LOCAL
COOLING. H85 TEMPERATURES QUICKLY WARM UP AHEAD OF THE SHORTWAVE
WITH STEEPENING LAPSE RATES. WHILE THE DEFORMATION BAND SWINGS
THROUGH THE AREA...THE COVERAGE DECREASES...MEANWHILE...SCATTERED
SHOWERS SHOULD DEVELOP THIS AFTERNOON WITH THE SHORTWAVE.
VERY STRONG WINDS WERE NOTED ON THE BACKSIDE OF THE SHORTWAVE WITH
50KT H85 WINDS. THERE ARE A NUMBER OF WIND RELATED HEADLINES WITH
THIS. THE WINDS TRY TO WEAKEN AS THEY MOVE SOUTHWARD...HOWEVER
THIS WILL NEED TO BE WATCHED AND A A WIND ADVISORY MAY BE NEEDED
THIS AFTERNOON. HIGH TEMPERATURES SHOULD BE IN THE 40S TO LOWER
50S. COLD ADVECTION CONTINUES THURSDAY WITH HIGHS IN THE 40S.
THE FIRST AREA OF WIDESPREAD SNOW MAY OCCUR FRIDAY. A SHORTWAVE
IN THE NORTHWEST FLOW ALOFT SHOULD DEVELOP A BAND OF LIGHT SNOW
FRIDAY. INCREASING OMEGA...FRONTOGENESIS AND STEEPENING LAPSE
RATES SHOULD IN SOME 1 TO 4 INCHES OF LIGHT SNOW. WITH LIFT IN THE
DENDRITIC LAYER AND DEPENDING ON WHERE THE BEST FORCING SETS
UP...HIGHER AMOUNTS ARE POSSIBLE.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 342 AM CST WED NOV 18 2015
WITH THE EXPECTED
SNOW...DID LOWER LOWS SATURDAY MORNING AND HIGHS SATURDAY WITH
HIGHS IN THE UPPER 20S TO UPPER 30S. STILL COLDER FOR SUNDAY WITH
HIGHS IN THE 30S AND 40S. TEMPERATURES WARM INTO THE 40S AND 50S
FOR THE REST OF THE EXTENDED.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 525 AM CST WED NOV 18 2015
CONDITIONS AT 1125Z WERE MAINLY IN THE IFR CATEGORY AROUND THE
AREA. EXPECT SOME LIGHT PCPN THIS MORNING THEN A BREAK IS LIKELY
FROM LATE MORNING INTO THE EARLY PART OF THE AFTN. NOT SURE IF
ANOTHER AREA OF LIGHT PCPN AND LOWER CIGS WILL DEVELOP LATER THIS
AFTN AT THE TAF SITES AS THE MOST RECENT HRRR RUNS SHOWED...SO
CONFIDENCE IS NOT OVERLY HIGH.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...MILLER
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
525 AM CST WED NOV 18 2015
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 342 AM CST WED NOV 18 2015
...POTENTIAL FOR FIRST WIDESPREAD SNOW OF THE SEASON FRIDAY...
FORECAST CONCERNS IN THE SHORT TERM WILL CONTINUE TO BE
PRECIPITATION WITH THE LARGE WEATHER SYSTEM TODAY AS LIFTS
NORTHEAST OUT OF THE AREA...RAIN OR A RAIN/SNOW MIX AND POTENTIAL
FOR WIND HEADLINES...ATTENTION THEN TURNS TO THE POTENTIAL FOR A
SWATH OF SNOW ACROSS PARTS OF SD/NE/IA/WI AND COLDER TEMPERATURES.
AT 0930Z...THE REGIONAL WSR-88D MOSAIC RADAR SHOWED A SPREAD OUT
PRECIPITATION PATTERN WITH RAIN WRAPPING AROUND THE ELONGATED UPPER
LOW PRESSURE SYSTEM FROM IOWA...TOWARD MINNESOTA AND SOUTH DAKOTA
AND BACK TOWARD CENTRAL NEBRASKA. SHOWERS ARE BEGINNING TO RE-
DEVELOP IN THE VICINITY OF THE H5 LOW CENTER OVER NORTHEAST
KANSAS. THUNDERSTORMS WERE NOTED WITH THE ELEVATED INSTABILITY
OVER MINNESOTA AND A MIX OF RAIN/SNOW AND SNOW TOWARD ONEILL AND
KEARNEY.
THE NEXT FEATURE OF INTEREST IS A STRONG SHORTWAVE OVER MONTANA
THAT WILL DIVE SOUTHEAST IN RESPONSE TO A 110KT UPR LEVEL JET.
IMPRESSIVE WINDS WERE NOTED OVERNIGHT WITH MANY STATIONS SUSTAINED
AT 40KTS GUSTING TO OVER 50KTS.
THE DETERMINISTIC MODELS ARE IN GOOD AGREEMENT WITH THE TRACK OF THE
H5 LOW WITH 200M HEIGHT FALLS...OVER NORTHEAST KANSAS (A LITTLE
SOUTHEAST OF WHERE IT WAS FORECAST TO BE YESTERDAY)...LIFTS NORTHEAST
INTO IOWA BY 18Z AND THE U.P. BY 00Z. THE LARGE AREA OF SURFACE
LOW PRESSURE WITH LOCAL MINIMUMS IN KANSAS AND WESTERN
IOWA...WILL CONSOLIDATE OVER MINNESOTA DURING THE DAY.
MEANWHILE...THE SHORTWAVE RACES SOUTHEAST TOWARD NEBRASKA WITH
WARMING H85 TEMPERATURES AHEAD OF IT.
COMPLEX PRECIPITATION FORECAST WITH ONE SYSTEM EXITING THE
AREA...WHILE THE NEXT RACES IN BEHIND IT OVER THE NEXT 12HRS. HAVE
THREE AREAS OF PRECIPITATION...THE AREA CLOSER TO THE SURFACE
FRONT...THE DEFORMATION BAND...AND THE PRECIPITATION ASSOCIATED
WITH THE SHORTWAVE. THERE MAY BE A MIX OF RAIN OR SNOW WITH THE
DEFORMATION BAND AND THERE COULD BE SOME SNOW MIXED IN AS THE
DEPTH OF THE COLD AIR INCREASES OR AREAS WHERE THERE IS LOCAL
COOLING. H85 TEMPERATURES QUICKLY WARM UP AHEAD OF THE SHORTWAVE
WITH STEEPENING LAPSE RATES. WHILE THE DEFORMATION BAND SWINGS
THROUGH THE AREA...THE COVERAGE DECREASES...MEANWHILE...SCATTERED
SHOWERS SHOULD DEVELOP THIS AFTERNOON WITH THE SHORTWAVE.
VERY STRONG WINDS WERE NOTED ON THE BACKSIDE OF THE SHORTWAVE WITH
50KT H85 WINDS. THERE ARE A NUMBER OF WIND RELATED HEADLINES WITH
THIS. THE WINDS TRY TO WEAKEN AS THEY MOVE SOUTHWARD...HOWEVER
THIS WILL NEED TO BE WATCHED AND A A WIND ADVISORY MAY BE NEEDED
THIS AFTERNOON. HIGH TEMPERATURES SHOULD BE IN THE 40S TO LOWER
50S. COLD ADVECTION CONTINUES THURSDAY WITH HIGHS IN THE 40S.
THE FIRST AREA OF WIDESPREAD SNOW MAY OCCUR FRIDAY. A SHORTWAVE
IN THE NORTHWEST FLOW ALOFT SHOULD DEVELOP A BAND OF LIGHT SNOW
FRIDAY. INCREASING OMEGA...FRONTOGENESIS AND STEEPENING LAPSE
RATES SHOULD IN SOME 1 TO 4 INCHES OF LIGHT SNOW. WITH LIFT IN THE
DENDRITIC LAYER AND DEPENDING ON WHERE THE BEST FORCING SETS
UP...HIGHER AMOUNTS ARE POSSIBLE.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 342 AM CST WED NOV 18 2015
WITH THE EXPECTED
SNOW...DID LOWER LOWS SATURDAY MORNING AND HIGHS SATURDAY WITH
HIGHS IN THE UPPER 20S TO UPPER 30S. STILL COLDER FOR SUNDAY WITH
HIGHS IN THE 30S AND 40S. TEMPERATURES WARM INTO THE 40S AND 50S
FOR THE REST OF THE EXTENDED.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 525 AM CST WED NOV 18 2015
CONDITIONS AT 1125Z WERE MAINLY IN THE IFR CATEGORY AROUND THE
AREA. EXPECT SOME LIGHT PCPN THIS MORNING THEN A BREAK IS LIKELY
FROM LATE MORNING INTO THE EARLY PART OF THE AFTN. NOT SURE IF
ANOTHER AREA OF LIGHT PCPN AND LOWER CIGS WILL DEVELOP LATER THIS
AFTN AT THE TAF SITES AS THE MOST RECENT HRRR RUNS SHOWED...SO
CONFIDENCE IS NOT OVERLY HIGH.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1259 AM CST WED NOV 18 2015
.UPDATE...
ISSUED AT 631 PM CST TUE NOV 17 2015
RAIN HAS CHANGED OVER TO SNOW IN CAMBRIDGE LOCATED IN WESTERN
FURNAS COUNTY. THE 18Z NAM WAS INDICATING THAT A WARM LAYER
LOCATED AROUND 775 MB WOULD RAPIDLY COOL TO BELOW FREEZING WITHIN
THE DEFORMATION BAND BETWEEN 6 PM AND 9 PM. THIS COOLING IF IT
MATERIALIZES WOULD TURN THE RAIN OVER TO SNOW PRIOR TO 9 PM FOR
MOST LOCATIONS WEST OF AN ORD...KEARNEY...ALMA LINE. THE FACT THAT
CAMBRIDGE HAS TURNED OVER TO SNOW WOULD INDICATE THAT THE COOLING
OF THIS WARM LAYER IS NOW UNDERWAY AND EXPECT AN INCREASING
LIKELIHOOD OF A CHANGE OVER TO SNOW IN THE ALREADY MENTIONED AREAS
SHORTLY. ONCE THE RAIN CHANGES OVER TO SNOW THE SFC TEMPERATURES
WILL QUICKLY FALL INTO THE 31 TO 33F RANGE AND SNOW WILL BEGIN
ACCUMULATING.
MOST OF THE SNOW IS EXPECTED TO REMAIN WEST OF THE HASTINGS AND
GRAND ISLAND AREA...ALTHOUGH WE CAN NOT RULE OUT A LITTLE LIGHT
SNOW LATE TONIGHT EVENTUALLY MAKING IT AS FAR EAST AS GRAND ISLAND
AND HASTINGS.
&&
.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 06Z KGRI/KEAR TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1259 AM CST WED NOV 18 2015
CEILINGS/VISIBILITY/PRECIPITATION TIMING AND TYPE WILL REMAIN
TRICKY THROUGH AT LEAST THESE FIRST 6-9 HOURS...BUT A FAIRLY
CLEAR-CUT RETURN TO VFR CONDITIONS IS ANTICIPATED FOR THE MAJORITY
OF THE PERIOD. STARTING OFF EARLY THIS MORNING...PATCHY LIGHT
DRIZZLE IS AFFECTING THE AREA...WHILE A STEADIER BAND OF
ACCUMULATING SLUSHY SNOW HAS PIVOTED GENERALLY 20-50 MILES OFF TO
THE WEST OF THE TERMINALS. AS WE NEAR SUNRISE...THIS PRECIP BAND
IS EXPECTED TO SHIFT BACK EASTWARD AND COULD GIVE BOTH KEAR/KGRI A
PERIOD OF LIGHT SNOW ACCUMULATION DURING SOME PORTION OF THE
09Z-15Z TIME FRAME BEFORE DEPARTING TO THE EAST OF BOTH SITES FOR
GOOD. UNTIL THAT HAPPENS...EXPECT A VARIED MIX OF IFR/MVFR/LOW-END
VFR CEILING AND VFR/MVFR VISIBILITY...DEPENDING SOMEWHAT ON PRECIP
INTENSITY.
FOR THE LATTER HALF OF THE PERIOD...INTRODUCED A "VICINITY SHOWER"
(VCSH) MENTION FOR A FEW HOURS IN THE AFTERNOON TO ACCOUNT FOR THE
POSSIBILITY OF SOME PASSING LIGHT RAIN SHOWERS...BUT THESE SHOULD
BE GONE BY SUNSET AND EXPECT ASSOCIATED CEILINGS TO DROP NO LOWER
THAN LOW-END VFR.
AS FOR SURFACE WIND...DIRECTION WILL PREVAIL FROM A WEST-
NORTHWEST DIRECTION WITH SUSTAINED SPEEDS GENERALLY 12-16KT
THROUGH MOST OF THE PERIOD WITH SOME HIGHER GUSTS AT TIMES.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
NEZ039-046-060-061-072-073-082.
KS...NONE.
&&
$$
UPDATE...WESELY
SHORT TERM...HEINLEIN
LONG TERM...ADP
AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
237 PM EST WED NOV 18 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER NEW ENGLAND THROUGH
TODAY...BRINGING DRY WEATHER WITH TEMPERATURES MODERATING INTO THE
UPPER 40S TO LOWER 50S THIS AFTERNOON. A FRONTAL SYSTEM
APPROACHING FROM THE GREAT LAKES AND OHIO RIVER VALLEY WILL BRING
INCREASINGLY WINDY AND MILD CONDITIONS FOR WEDNESDAY NIGHT INTO
THURSDAY. THE APPROACHING FRONT WILL ALSO BRING A PERIOD OF LIGHT
TO MODERATE RAIN TO NORTHERN NEW YORK AND VERMONT...MAINLY
THURSDAY AFTERNOON INTO THURSDAY NIGHT. SLIGHTLY COOLER WEATHER IS
EXPECTED FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 1216 PM EST WEDNESDAY...MAINLY UPDATED FORECAST TO REFLECT
CURRENT CONDITIONS AND SATELLITE TRENDS. CLOUDS ARE STARTING TO
MOVE INTO THE AREA FROM THE SOUTHWEST. GOING FORECAST IS IN GOOD
SHAPE. PREVIOUS DISCUSSIONS FOLLOW.
OTHER THAN THE GUSTY SOUTHERLY WINDS THERE ISN`T MUCH GOING ON
THIS MORNING WEATHER WISE. MOSTLY CLEAR SKIES HAVE COMBINED WITH
GUSTY SOUTHERLY WINDS TO INCREASE TEMPS IN THE CHAMPLAIN VALLEY A
BIT MORE THAT PREVIOUSLY FORECAST SO I TWEAKS UP TEMPS IN THE
VALLEY A BY A COUPLE OF DEGREES BUT THE WARM AIR ADVECTION HAS
STILL YET TO REACH PARTS OF THE NORTHEAST KINGDOM SO I SLOWED DOWN
HOW QUICKLY WE WARM UP THERE. ADDITIONALLY THERE`S A STRONG
INVERSION ALOFT SO I UPDATED THE MOUNTAIN SUMMIT TEMPS ESPECIALLY
OVER NORTHERN NEW YORK WHERE THE TEMPERATURE DIFFERENCE BETWEEN
SLK AND WHITEFACE MOUNTAIN IS 11 DEGREES. ULTIMATELY THIS HAD
LITTLE CHANGE IN THE OVERALL WEATHER PICTURE AND WAS MORE COSMETIC
THAN PHYSICAL. THE REST OF THE FORECAST IS IN GOOD SHAPE WITH NO
CHANGES.
PREVIOUS DISCUSSION AS OF 634 AM EST WEDNESDAY...SFC-850MB RIDGE
AXIS CENTERED ALONG THE NEW ENGLAND COAST BRINGING A CHILLY
MORNING TO VALLEY LOCATIONS...BUT ALREADY SEEING STRONG WARMING
ALOFT WITH 850MB TEMPS AROUND +6C AT BTV AND +9C ACROSS ST.
LAWRENCE COUNTY NY PER 10Z RUC ANALYSIS. EVIDENCE OF THIS IN THE
SFC OBSERVATIONS WITH 11Z READINGS OF 12F AT SLK...BUT 37F ATOP
WHITEFACE MOUNTAIN WITH 35KT SWLY WINDS. ALSO - AFTER A LOW OF
25F AROUND MIDNIGHT - BTV HAS CLIMBED TO 37F AT 11Z AIDED BY
VALLEY CHANNELED SOUTHERLY FLOW OF 10-12KTS. 2-M TEMPS WILL CLIMB
RELATIVELY QUICKLY AREAWIDE AFTER SUNRISE AS SOUTHERLY RETURN FLOW
INCREASES ON WRN PERIPHERY OF THE ANTICYCLONE AND AS RADIATIONAL
INVERSIONS BREAK.
SOUTHERLY WINDS REACH 10-20 MPH THIS AFTERNOON WITH GUSTS TO
25-30 MPH...ESPECIALLY IN THE CHAMPLAIN VALLEY WITH CHANNELED
FLOW. WILL SEE A GRADUAL INCREASE IN MID-UPR CLOUDS THIS AFTERNOON
ASSOCIATED WITH HIGHLY AMPLIFIED AND SLOW MOVING 500MB TROUGH
ACROSS THE CENTRAL PLAINS STATES. DESPITE A BIT OF FILTERED
SUN...W/ 925MB TEMPS MODERATING TO AROUND +6C THIS AFTERNOON AND
GOOD LOW-LEVEL MIXING SHOULD SEE HIGHS REACHING 5 TO 8 DEG WARMER
THAN YESTERDAY...AND GENERALLY IN THE UPR 40S TO LOWER 50S IN
VALLEY LOCATIONS. WARMEST READINGS LIKELY IN WRN ST. LAWRENCE
COUNTY NY; LOCALLY IN THE MID 50S.
TEMPERATURES WILL NOT FALL MUCH TONIGHT WITH CONTINUED SLY
GRADIENT FLOW KEEPING SFC WINDS 10-20 MPH WITH GUSTS 25-35 MPH IN
THE CHAMPLAIN VALLEY. 925MB WINDS REACH 55KTS BY 08Z ACROSS THE
CHAMPLAIN VALLEY...SO WILL BE QUITE WINDY ACROSS THE RIDGE TOPS.
MAY SEE SOME LOCALIZED SURFACE GUSTS TO 40 MPH IN THE CHAMPLAIN
VALLEY LATE TONIGHT...BUT RELATIVELY STABLE CONDITIONS BELOW THE
LOW-LEVEL JET SHOULD KEEP GUSTS FROM REACHING MUCH HIGHER.
LOOKING AT LOW TEMPS MAINLY IN THE LOW-MID 40S WEST OF THE GREEN
MTNS...AND LOCALLY UPR 30S EAST OF THE GREENS. WILL SEE A
CONTINUED INCREASE IN CLOUD COVER...WITH POSSIBLE STRATUS LAYER
SPREADING NORTHWARD INTO THE REGION DURING THE OVERNIGHT HRS AS
WELL. IT APPEARS MOST OF THE PRECIPITATION WILL HOLD OFF UNTIL
DURING THE DAY THURSDAY INCLUDED JUST A SLIGHT CHANCE OF A PRE-
DAWN SHOWER ACROSS THE ADIRONDACKS AND ST. LAWRENCE COUNTY NY.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
AS OF 305 AM EST WEDNESDAY... THIS PERIOD WILL BE A TRANSITION
FROM STRONG RIDGE TO DEVELOPING MID/UPPER LEVEL TROUGH ASSOCIATED
WITH COLD FRONT AND DIGGING SHORT WAVE ENERGY OVER THE GREAT
LAKES. INITIAL 5H VORT APPROACHES OUR WESTERN CWA AROUND 12Z
THURSDAY ALONG WITH A RIBBON OF ENHANCED 850 TO 500MB MOISTURE AND
PW VALUES APPROACHING 1.0". EXPECT SHOWERS TO DEVELOP ACROSS
NORTHERN NEW YORK BETWEEN 12Z AND 15Z...THEN SLOWLY SHIFT EAST
INTO THE CHAMPLAIN VALLEY AROUND 18Z...AND INTO EASTERN VT BY
SUNSET. THE ECMWF CONTINUES TO SHOW SHOWERS PERSISTING OVERNIGHT
ACROSS CHAMPLAIN VALLEY AND CENTRAL/EASTERN VT AS ADDITIONAL
MOISTURE ADVECTION OCCURS AHEAD OF BOUNDARY ASSOCIATED WITH LOW
LEVEL JET OF 50 KNOTS. SOUNDINGS SHOW LIMITED MIXING OF LOW LEVEL
JET TO THE SURFACE ON THURSDAY...WITH BEST CHANCE OF WITNESS A FEW
GUSTS BETWEEN 35 AND 40 MPH ACROSS THE ALIGNED SOUTH TO NORTH
VALLEYS AND OVER THE EXPOSED HIGHER TERRAIN. GIVEN THE STRONG
850MB TO 925MB WIND FIELD EXPECT SOME TERRAIN DRIVEN EFFECTS TO
THE QPF ACROSS OUR REGION. HIGHEST QPF VALUES OF AN INCH WILL
OCCUR ACROSS THE MOUNTAINS OF CENTRAL/EASTERN VT AND PARTS OF THE
EASTERN DACKS WITH A 0.25 TO 0.75 IN THE SAINT
LAWRENCE...CHAMPLAIN..AND PARTS OF THE CT RIVER VALLEYS. PROGGED
850MB TEMPS PEAK BETWEEN 6-8C AHEAD OF BOUNDARY ON THURSDAY...BUT
CLOUDS/PRECIP WILL LIMIT MIXING. THINKING HIGHS WILL RANGE FROM
THE MID 40S MTNS TO MID/UPPER 50S WARMER VALLEY LOCATIONS. IF SOME
SUN DEVELOPS AHEAD OF RAIN ACROSS THE CHAMPLAIN VALLEY
TEMPERATURES COULD BRIEFLY REACH THE LOWER 60S WITH BREEZY
SOUTHERLY WINDS ON THURSDAY.
ON FRIDAY OUR FORECAST AREA IS UNDER MODERATE LOW LEVEL COLD AIR
ADVECTION AS SHORT WAVE RACES TOWARD NORTHERN MAINE. DEEP DRY SLOT
WITH PWS FALLING BETWEEN 0.25 AND 0.33 DEVELOPS ACROSS OUR CWA BY
18Z...BUT PLENTY OF MOISTURE TRAPPED BELOW SUBSIDENCE INVERSION
WILL RESULT IN MOSTLY CLOUDY SKIES WITH CLEARING IN THE AFTERNOON.
ECMWF STILL SHOWS SOME LINGERING SHOWERS WHICH COULD END AS A FEW
WET SNOW FLAKES ACROSS THE HIGHER TERRAIN OF CENTRAL/EASTERN VT ON
FRIDAY MORNING BETWEEN 12Z-15Z. TEMPERATURES WILL REMAIN MAINLY IN
THE MID/UPPER 30S MOUNTAINS TO MID/UPPER 40S VALLEYS ON FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 305 AM EST WEDNESDAY...WEAK SURFACE RIDGE BUILDS ACROSS
NORTHERN NY ON FRIDAY NIGHT WITH CLEAR SKIES AND LIGHT WINDS.
TEMPERATURES WILL COOL INTO THE TEENS IN THE DEEPER MOUNTAIN
VALLEYS AND MID 20S IN THE CHAMPLAIN VALLEY. IF MORE CLOUDS ARE
PRESENT THAN EXPECTED...TEMPERATURES COULD BE 2 TO 5 DEGREES
WARMER. QUIET WEATHER IS EXPECTED SATURDAY WITH NEAR NORMAL
TEMPERATURES. NEXT POTENT SHORT WAVE ENERGY AND ASSOCIATED TROUGH
IMPACT OUR CWA ON SUNDAY. AS WE THOUGHT YESTERDAY...THE SURFACE
LOW PRES TRACK AND ASSOCIATED CLOSED 5H/7H CIRCULATION IS TRACKING
TO OUR NORTH AND REMAINS FAIRLY PROGRESSIVE IN THE FAST WESTERLY
FLOW ALOFT. THIS WILL LIMIT DEEP MOISTURE ADVECTION ON THE
BACKSIDE AND RESULT IN MAINLY TERRAIN DRIVEN SNOW SHOWERS ON
SUNDAY. HOWEVER...GIVEN THE EXTREMELY STRONG DYNAMICS OF THE
SYSTEM AND TIMING OF SECONDARY SURGE OF COLD AIR DURING THE LATE
MORNING/EARLY AFTERNOON...THINKING A FEW HEAVIER CONVECTION RAIN
AND SNOW SHOWERS WILL BE POSSIBLE...ESPECIALLY OVER THE MOUNTAINS.
THIS SYSTEM HAS THE POTENTIAL TO PRODUCE A BURST OF A FEW INCHES
OF SNOW IN A SHORT PERIOD OF TIME. BY 00Z MONDAY PROGGED 850MB
TEMPS DROP TO -8C WITH 925MB TEMPS BETWEEN -2C AND -4C...WHICH
WILL RESULT SNOW LEVELS NEAR THE VALLEY FLOOR. HOWEVER...MOISTURE
WILL BE QUICKLY LIFTING NORTH OF OUR CWA AND MAINLY CONFINED TO
THE UPSLOPE REGIONS OF THE NORTHERN DACKS AND CENTRAL/NORTHERN
GREEN MOUNTAINS. ANY LEFTOVER SNOW SHOWER ACTIVITY WILL DISSIPATE
BY 06Z MONDAY WITH MOISTURE QUICKLY DISSIPATING. EARLY INDICATIONS
WOULD BE FOR SEVERAL INCHES LIKELY IN THE MOUNTAINS ABOVE 2000
FEET WITH 4 OR 5 INCHES POSSIBLE NEAR THE SUMMIT BY SUNDAY EVENING
WITH A DUSTING TO 2 INCHES BETWEEN 1000 AND 2000 FEET.
TEMPERATURES ON SUNDAY WILL RANGE FROM THE LOWER 30S MOUNTAIN
TOWNS TO LOWER 40S WARMER VALLEYS. EXPECT MID WINTER CONDITIONS ON
MOUNTAIN SUMMITS ON SUNDAY WITH BLUSTERY WINDS AND AREAS OF SNOW
SHOWERS.
MID/UPPER LEVEL TROUGH CONTINUES FOR EARLY NEXT WEEK AS SURFACE
RIDGE OF HIGH PRESSURE BUILDS INTO OUR CWA. THIS WILL RESULT IN
DRYING CONDITIONS WITH BELOW NORMAL TEMPERATURES FOR MONDAY AND
TUESDAY. A FEW LINGERING LIGHT MOUNTAIN SNOW FLURRIES ARE POSSIBLE
WITH TEMPERATURES MAINLY IN THE MID/UPPER 20S TO LOWER 40S.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...VFR THROUGH 00Z THU...THEN POTENTIAL MVFR
STRATUS DEVELOPING FROM SOUTH TO NORTH DURING THE OVERNIGHT
PERIOD. CLEAR SKIES ARE GIVING WAY TO THIN HIGH CLOUDS FROM
20-25KFT AGL, WHICH WILL TEND TO THICKEN THIS EVENING. WINDS SOUTH
10-15 KNOTS WITH GUSTS TO 20 KNOTS THIS AFTERNOON. LOCAL GUSTS TO
30 KNOTS EXPECTED AT BTV TONIGHT. JUST A SLIGHT CHANCE OF -SHRA AT
MSS/SLK DURING THE PRE-DAWN HRS THURSDAY. INCREASING LOW-LEVEL JET
TONIGHT BRINGS PROSPECTS FOR LLWS...BEGINNING AT SLK AT 19/00Z
CENTERED AROUND 2KFT...AND AT MPV BY 06Z. CHANCE FOR SHOWERS
INCREASES AFTER 12Z THURSDAY...BUT HAVE NOT INCLUDED PREVAILING
SHOWERS YET. WINDS WILL ALSO INCREASE OUT OF THE SOUTH WITH
PRESSURE GRADIENT STRENGTHENING BETWEEN DEPARTING HIGH PRESSURE
AND FRONTAL SYSTEM APPROACHING FROM OHIO VALLEY. GUSTS UP TO 40
MPH ARE POSSIBLE...ESPECIALLY AT BTV WITH CHANNELED VALLEY FLOW.
OUTLOOK 18Z THURSDAY THROUGH MONDAY...PERIODS OF MVFR CONDITIONS
EXPECTED THURSDAY AFTERNOON INTO THURSDAY NIGHT WITH LIGHT TO
MODERATE RAINFALL. TRENDING BACK TO VFR FOR FRI/SAT. SAT NIGHT AND
SUNDAY MAY HAVE SOME MVFR WITH SNOW SHOWERS...ESPECIALLY MOUNTAIN
LOCATIONS. THEN VFR RETURNS FOR MONDAY.
&&
.MARINE...
STRONG SOUTHERLY WINDS AHEAD OF APPROACHING TROUGH AND ASSOCIATED
COLD FRONT ARE CURRENTLY IN THE THE CHAMPLAIN VALLEY AND PERSIST
THROUGH THURSDAY EVENING. WINDS ARE CURRENTLY 15-25 KNOTS AND WILL
INCREASE TOMORROW TO 20-30 KNOTS BEFORE WEAKENING TOMORROW
EVENING.
&&
.EQUIPMENT...
AS OF 650 PM EST MONDAY...FOR YOUR INFORMATION...THE AUTOMATED
SURFACE OBSERVING SYSTEM (ASOS) AT THE MORRISVILLE-STOWE STATE
AIRPORT (KMVL) IN MORRISVILLE VERMONT WILL BE OUT OF SERVICE FOR A
FEW DAYS THIS WEEK...AS IT IS BEING PHYSICALLY RELOCATED TO
ANOTHER LOCATION ON THE AIRPORT GROUNDS. THUS...ONLY THE ALTIMETER
SETTING WILL BE AVAILABLE FROM THIS SITE. THERE WILL BE NO
TEMPERATURE...DEW POINT...SURFACE WIND...PRESENT WEATHER AND
CEILING BEING REPORTED UNTIL AFTER THE ASOS HAS BEEN RELOCATED.
FOR AVIATION INTERESTS...THE FAA ALREADY HAS A NOTAM OUT ABOUT THE
ASOS OUTAGE AT KMVL.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS/NEILES
NEAR TERM...BANACOS/NEILES
SHORT TERM...TABER
LONG TERM...TABER
AVIATION...BANACOS/NEILES
MARINE...VERASAMY
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1238 PM EST WED NOV 18 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER NEW ENGLAND THROUGH
TODAY...BRINGING DRY WEATHER WITH TEMPERATURES MODERATING INTO THE
UPPER 40S TO LOWER 50S THIS AFTERNOON. A FRONTAL SYSTEM
APPROACHING FROM THE GREAT LAKES AND OHIO RIVER VALLEY WILL BRING
INCREASINGLY WINDY AND MILD CONDITIONS FOR WEDNESDAY NIGHT INTO
THURSDAY. THE APPROACHING FRONT WILL ALSO BRING A PERIOD OF LIGHT
TO MODERATE RAIN TO NORTHERN NEW YORK AND VERMONT...MAINLY
THURSDAY AFTERNOON INTO THURSDAY NIGHT. SLIGHTLY COOLER WEATHER IS
EXPECTED FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AS OF 1216 PM EST WEDNESDAY...MAINLY UPDATED FORECAST TO REFLECT
CURRENT CONDITIONS AND SATELLITE TRENDS. CLOUDS ARE STARTING TO
MOVE INTO THE AREA FROM THE SOUTHWEST. GOING FORECAST IS IN GOOD
SHAPE. PREVIOUS DISCUSSIONS FOLLOW.
OTHER THAN THE GUSTY SOUTHERLY WINDS THERE ISN`T MUCH GOING ON
THIS MORNING WEATHER WISE. MOSTLY CLEAR SKIES HAVE COMBINED WITH
GUSTY SOUTHERLY WINDS TO INCREASE TEMPS IN THE CHAMPLAIN VALLEY A
BIT MORE THAT PREVIOUSLY FORECAST SO I TWEAKS UP TEMPS IN THE
VALLEY A BY A COUPLE OF DEGREES BUT THE WARM AIR ADVECTION HAS
STILL YET TO REACH PARTS OF THE NORTHEAST KINGDOM SO I SLOWED DOWN
HOW QUICKLY WE WARM UP THERE. ADDITIONALLY THERE`S A STRONG
INVERSION ALOFT SO I UPDATED THE MOUNTAIN SUMMIT TEMPS ESPECIALLY
OVER NORTHERN NEW YORK WHERE THE TEMPERATURE DIFFERENCE BETWEEN
SLK AND WHITEFACE MOUNTAIN IS 11 DEGREES. ULTIMATELY THIS HAD
LITTLE CHANGE IN THE OVERALL WEATHER PICTURE AND WAS MORE COSMETIC
THAN PHYSICAL. THE REST OF THE FORECAST IS IN GOOD SHAPE WITH NO
CHANGES.
PREVIOUS DISCUSSION AS OF 634 AM EST WEDNESDAY...SFC-850MB RIDGE
AXIS CENTERED ALONG THE NEW ENGLAND COAST BRINGING A CHILLY
MORNING TO VALLEY LOCATIONS...BUT ALREADY SEEING STRONG WARMING
ALOFT WITH 850MB TEMPS AROUND +6C AT BTV AND +9C ACROSS ST.
LAWRENCE COUNTY NY PER 10Z RUC ANALYSIS. EVIDENCE OF THIS IN THE
SFC OBSERVATIONS WITH 11Z READINGS OF 12F AT SLK...BUT 37F ATOP
WHITEFACE MOUNTAIN WITH 35KT SWLY WINDS. ALSO - AFTER A LOW OF
25F AROUND MIDNIGHT - BTV HAS CLIMBED TO 37F AT 11Z AIDED BY
VALLEY CHANNELED SOUTHERLY FLOW OF 10-12KTS. 2-M TEMPS WILL CLIMB
RELATIVELY QUICKLY AREAWIDE AFTER SUNRISE AS SOUTHERLY RETURN FLOW
INCREASES ON WRN PERIPHERY OF THE ANTICYCLONE AND AS RADIATIONAL
INVERSIONS BREAK.
SOUTHERLY WINDS REACH 10-20 MPH THIS AFTERNOON WITH GUSTS TO
25-30 MPH...ESPECIALLY IN THE CHAMPLAIN VALLEY WITH CHANNELED
FLOW. WILL SEE A GRADUAL INCREASE IN MID-UPR CLOUDS THIS AFTERNOON
ASSOCIATED WITH HIGHLY AMPLIFIED AND SLOW MOVING 500MB TROUGH
ACROSS THE CENTRAL PLAINS STATES. DESPITE A BIT OF FILTERED
SUN...W/ 925MB TEMPS MODERATING TO AROUND +6C THIS AFTERNOON AND
GOOD LOW-LEVEL MIXING SHOULD SEE HIGHS REACHING 5 TO 8 DEG WARMER
THAN YESTERDAY...AND GENERALLY IN THE UPR 40S TO LOWER 50S IN
VALLEY LOCATIONS. WARMEST READINGS LIKELY IN WRN ST. LAWRENCE
COUNTY NY; LOCALLY IN THE MID 50S.
TEMPERATURES WILL NOT FALL MUCH TONIGHT WITH CONTINUED SLY
GRADIENT FLOW KEEPING SFC WINDS 10-20 MPH WITH GUSTS 25-35 MPH IN
THE CHAMPLAIN VALLEY. 925MB WINDS REACH 55KTS BY 08Z ACROSS THE
CHAMPLAIN VALLEY...SO WILL BE QUITE WINDY ACROSS THE RIDGE TOPS.
MAY SEE SOME LOCALIZED SURFACE GUSTS TO 40 MPH IN THE CHAMPLAIN
VALLEY LATE TONIGHT...BUT RELATIVELY STABLE CONDITIONS BELOW THE
LOW-LEVEL JET SHOULD KEEP GUSTS FROM REACHING MUCH HIGHER.
LOOKING AT LOW TEMPS MAINLY IN THE LOW-MID 40S WEST OF THE GREEN
MTNS...AND LOCALLY UPR 30S EAST OF THE GREENS. WILL SEE A
CONTINUED INCREASE IN CLOUD COVER...WITH POSSIBLE STRATUS LAYER
SPREADING NORTHWARD INTO THE REGION DURING THE OVERNIGHT HRS AS
WELL. IT APPEARS MOST OF THE PRECIPITATION WILL HOLD OFF UNTIL
DURING THE DAY THURSDAY INCLUDED JUST A SLIGHT CHANCE OF A PRE-
DAWN SHOWER ACROSS THE ADIRONDACKS AND ST. LAWRENCE COUNTY NY.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH FRIDAY/...
AS OF 305 AM EST WEDNESDAY... THIS PERIOD WILL BE A TRANSITION
FROM STRONG RIDGE TO DEVELOPING MID/UPPER LEVEL TROUGH ASSOCIATED
WITH COLD FRONT AND DIGGING SHORT WAVE ENERGY OVER THE GREAT
LAKES. INITIAL 5H VORT APPROACHES OUR WESTERN CWA AROUND 12Z
THURSDAY ALONG WITH A RIBBON OF ENHANCED 850 TO 500MB MOISTURE AND
PW VALUES APPROACHING 1.0". EXPECT SHOWERS TO DEVELOP ACROSS
NORTHERN NEW YORK BETWEEN 12Z AND 15Z...THEN SLOWLY SHIFT EAST
INTO THE CHAMPLAIN VALLEY AROUND 18Z...AND INTO EASTERN VT BY
SUNSET. THE ECMWF CONTINUES TO SHOW SHOWERS PERSISTING OVERNIGHT
ACROSS CHAMPLAIN VALLEY AND CENTRAL/EASTERN VT AS ADDITIONAL
MOISTURE ADVECTION OCCURS AHEAD OF BOUNDARY ASSOCIATED WITH LOW
LEVEL JET OF 50 KNOTS. SOUNDINGS SHOW LIMITED MIXING OF LOW LEVEL
JET TO THE SURFACE ON THURSDAY...WITH BEST CHANCE OF WITNESS A FEW
GUSTS BETWEEN 35 AND 40 MPH ACROSS THE ALIGNED SOUTH TO NORTH
VALLEYS AND OVER THE EXPOSED HIGHER TERRAIN. GIVEN THE STRONG
850MB TO 925MB WIND FIELD EXPECT SOME TERRAIN DRIVEN EFFECTS TO
THE QPF ACROSS OUR REGION. HIGHEST QPF VALUES OF AN INCH WILL
OCCUR ACROSS THE MOUNTAINS OF CENTRAL/EASTERN VT AND PARTS OF THE
EASTERN DACKS WITH A 0.25 TO 0.75 IN THE SAINT
LAWRENCE...CHAMPLAIN..AND PARTS OF THE CT RIVER VALLEYS. PROGGED
850MB TEMPS PEAK BETWEEN 6-8C AHEAD OF BOUNDARY ON THURSDAY...BUT
CLOUDS/PRECIP WILL LIMIT MIXING. THINKING HIGHS WILL RANGE FROM
THE MID 40S MTNS TO MID/UPPER 50S WARMER VALLEY LOCATIONS. IF SOME
SUN DEVELOPS AHEAD OF RAIN ACROSS THE CHAMPLAIN VALLEY
TEMPERATURES COULD BRIEFLY REACH THE LOWER 60S WITH BREEZY
SOUTHERLY WINDS ON THURSDAY.
ON FRIDAY OUR FORECAST AREA IS UNDER MODERATE LOW LEVEL COLD AIR
ADVECTION AS SHORT WAVE RACES TOWARD NORTHERN MAINE. DEEP DRY SLOT
WITH PWS FALLING BETWEEN 0.25 AND 0.33 DEVELOPS ACROSS OUR CWA BY
18Z...BUT PLENTY OF MOISTURE TRAPPED BELOW SUBSIDENCE INVERSION
WILL RESULT IN MOSTLY CLOUDY SKIES WITH CLEARING IN THE AFTERNOON.
ECMWF STILL SHOWS SOME LINGERING SHOWERS WHICH COULD END AS A FEW
WET SNOW FLAKES ACROSS THE HIGHER TERRAIN OF CENTRAL/EASTERN VT ON
FRIDAY MORNING BETWEEN 12Z-15Z. TEMPERATURES WILL REMAIN MAINLY IN
THE MID/UPPER 30S MOUNTAINS TO MID/UPPER 40S VALLEYS ON FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 305 AM EST WEDNESDAY...WEAK SURFACE RIDGE BUILDS ACROSS
NORTHERN NY ON FRIDAY NIGHT WITH CLEAR SKIES AND LIGHT WINDS.
TEMPERATURES WILL COOL INTO THE TEENS IN THE DEEPER MOUNTAIN
VALLEYS AND MID 20S IN THE CHAMPLAIN VALLEY. IF MORE CLOUDS ARE
PRESENT THAN EXPECTED...TEMPERATURES COULD BE 2 TO 5 DEGREES
WARMER. QUIET WEATHER IS EXPECTED SATURDAY WITH NEAR NORMAL
TEMPERATURES. NEXT POTENT SHORT WAVE ENERGY AND ASSOCIATED TROUGH
IMPACT OUR CWA ON SUNDAY. AS WE THOUGHT YESTERDAY...THE SURFACE
LOW PRES TRACK AND ASSOCIATED CLOSED 5H/7H CIRCULATION IS TRACKING
TO OUR NORTH AND REMAINS FAIRLY PROGRESSIVE IN THE FAST WESTERLY
FLOW ALOFT. THIS WILL LIMIT DEEP MOISTURE ADVECTION ON THE
BACKSIDE AND RESULT IN MAINLY TERRAIN DRIVEN SNOW SHOWERS ON
SUNDAY. HOWEVER...GIVEN THE EXTREMELY STRONG DYNAMICS OF THE
SYSTEM AND TIMING OF SECONDARY SURGE OF COLD AIR DURING THE LATE
MORNING/EARLY AFTERNOON...THINKING A FEW HEAVIER CONVECTION RAIN
AND SNOW SHOWERS WILL BE POSSIBLE...ESPECIALLY OVER THE MOUNTAINS.
THIS SYSTEM HAS THE POTENTIAL TO PRODUCE A BURST OF A FEW INCHES
OF SNOW IN A SHORT PERIOD OF TIME. BY 00Z MONDAY PROGGED 850MB
TEMPS DROP TO -8C WITH 925MB TEMPS BETWEEN -2C AND -4C...WHICH
WILL RESULT SNOW LEVELS NEAR THE VALLEY FLOOR. HOWEVER...MOISTURE
WILL BE QUICKLY LIFTING NORTH OF OUR CWA AND MAINLY CONFINED TO
THE UPSLOPE REGIONS OF THE NORTHERN DACKS AND CENTRAL/NORTHERN
GREEN MOUNTAINS. ANY LEFTOVER SNOW SHOWER ACTIVITY WILL DISSIPATE
BY 06Z MONDAY WITH MOISTURE QUICKLY DISSIPATING. EARLY INDICATIONS
WOULD BE FOR SEVERAL INCHES LIKELY IN THE MOUNTAINS ABOVE 2000
FEET WITH 4 OR 5 INCHES POSSIBLE NEAR THE SUMMIT BY SUNDAY EVENING
WITH A DUSTING TO 2 INCHES BETWEEN 1000 AND 2000 FEET.
TEMPERATURES ON SUNDAY WILL RANGE FROM THE LOWER 30S MOUNTAIN
TOWNS TO LOWER 40S WARMER VALLEYS. EXPECT MID WINTER CONDITIONS ON
MOUNTAIN SUMMITS ON SUNDAY WITH BLUSTERY WINDS AND AREAS OF SNOW
SHOWERS.
MID/UPPER LEVEL TROUGH CONTINUES FOR EARLY NEXT WEEK AS SURFACE
RIDGE OF HIGH PRESSURE BUILDS INTO OUR CWA. THIS WILL RESULT IN
DRYING CONDITIONS WITH BELOW NORMAL TEMPERATURES FOR MONDAY AND
TUESDAY. A FEW LINGERING LIGHT MOUNTAIN SNOW FLURRIES ARE POSSIBLE
WITH TEMPERATURES MAINLY IN THE MID/UPPER 20S TO LOWER 40S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...VFR THROUGH 00Z THU...THEN POTENTIAL MVFR
STRATUS DEVELOPING FROM SOUTH TO NORTH DURING THE OVERNIGHT
PERIOD. CLEAR SKIES ARE GIVING WAY TO THIN HIGH CLOUDS FROM
20-25KFT AGL, WHICH WILL TEND TO THICKEN THIS EVENING. WINDS SOUTH
10-15 KTS WITH GUSTS TO 20 KTS THIS AFTERNOON. LOCAL GUSTS TO 30
KTS EXPECTED AT BTV TONIGHT. JUST A SLIGHT CHANCE OF -SHRA AT
MSS/SLK DURING THE PRE-DAWN HRS THURSDAY. INCREASING LOW-LEVEL
JET TONIGHT BRINGS PROSPECTS FOR LLWS...BEGINNING AT SLK AT 19/00Z
CENTERED AROUND 2KFT...AND AT MPV BY 06Z. CHANCE FOR SHOWERS
INCREASES AFTER 12Z THURSDAY...BUT HAVE NOT INCLUDED PREVAILING
SHOWERS YET. WINDS WILL ALSO INCREASE OUT OF THE SOUTH WITH
PRESSURE GRADIENT STRENGTHENING BETWEEN DEPARTING HIGH PRESSURE
AND FRONTAL SYSTEM APPROACHING FROM OHIO VALLEY. GUSTS UP TO 40
MPH ARE POSSIBLE...ESPECIALLY AT BTV WITH CHANNELED VALLEY FLOW.
OUTLOOK 18Z THURSDAY THROUGH MONDAY...PERIODS OF MVFR CONDITIONS
EXPECTED THURSDAY AFTERNOON INTO THURSDAY NIGHT WITH LIGHT TO
MODERATE RAINFALL. TRENDING BACK TO VFR FOR FRI/SAT. SAT NIGHT AND
SUNDAY MAY HAVE SOME MVFR WITH SNOW SHOWERS...ESPECIALLY MOUNTAIN
LOCATIONS. THEN VFR RETURNS FOR MONDAY.
&&
.MARINE...
STRONG SOUTHERLY WINDS AHEAD OF APPROACHING TROUGH AND ASSOCIATED
COLD FRONT WILL MOVE THROUGH THE CHAMPLAIN VALLEY TODAY AND
PERSIST THROUGH THURSDAY AFTERNOON. EXPECT WINDS TO BE 15-25 KNOTS
TO TOADY AND INCREASING TOMORROW TO 20-30 KNOTS BEFORE WEAKENING
TOMORROW EVENING.
&&
.EQUIPMENT...
AS OF 650 PM EST MONDAY...FOR YOUR INFORMATION...THE AUTOMATED
SURFACE OBSERVING SYSTEM (ASOS) AT THE MORRISVILLE-STOWE STATE
AIRPORT (KMVL) IN MORRISVILLE VERMONT WILL BE OUT OF SERVICE FOR A
FEW DAYS THIS WEEK...AS IT IS BEING PHYSICALLY RELOCATED TO
ANOTHER LOCATION ON THE AIRPORT GROUNDS. THUS...ONLY THE ALTIMETER
SETTING WILL BE AVAILABLE FROM THIS SITE. THERE WILL BE NO
TEMPERATURE...DEW POINT...SURFACE WIND...PRESENT WEATHER AND
CEILING BEING REPORTED UNTIL AFTER THE ASOS HAS BEEN RELOCATED.
FOR AVIATION INTERESTS...THE FAA ALREADY HAS A NOTAM OUT ABOUT THE
ASOS OUTAGE AT KMVL.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/NEILES
SHORT TERM...TABER
LONG TERM...TABER
AVIATION...BANACOS/NEILES
MARINE...VERASAMY
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
933 AM EST WED NOV 18 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER NEW ENGLAND THROUGH
TODAY...BRINGING DRY WEATHER WITH TEMPERATURES MODERATING INTO THE
UPPER 40S TO LOWER 50S THIS AFTERNOON. A FRONTAL SYSTEM
APPROACHING FROM THE GREAT LAKES AND OHIO RIVER VALLEY WILL BRING
INCREASINGLY WINDY AND MILD CONDITIONS FOR WEDNESDAY NIGHT INTO
THURSDAY. THE APPROACHING FRONT WILL ALSO BRING A PERIOD OF LIGHT
TO MODERATE RAIN TO NORTHERN NEW YORK AND VERMONT...MAINLY THURSDAY
AFTERNOON INTO THURSDAY NIGHT. SLIGHTLY COOLER WEATHER IS EXPECTED
FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AS OF 933 AM EST WEDNESDAY...OTHER THAN THE GUSTY SOUTHERLY WINDS
THERE ISN`T MUCH GOING ON THIS MORNING WEATHER WISE. MOSTLY CLEAR
SKIES HAVE COMBINED WITH GUSTY SOUTHERLY WINDS TO INCREASE TEMPS
IN THE CHAMPLAIN VALLEY A BIT MORE THAT PREVIOUSLY FORECAST SO I
TWEAKS UP TEMPS IN THE VALLEY A BY A COUPLE OF DEGREES BUT THE
WARM AIR ADVECTION HAS STILL YET TO REACH PARTS OF THE NORTHEAST
KINGDOM SO I SLOWED DOWN HOW QUICKLY WE WARM UP THERE.
ADDITIONALLY THERE`S A STRONG INVERSION ALOFT SO I UPDATED THE
MOUNTAIN SUMMIT TEMPS ESPECIALLY OVER NORTHERN NEW YORK WHERE THE
TEMPERATURE DIFFERENCE BETWEEN SLK AND WHITEFACE MOUNTAIN IS 11
DEGREES. ULTIMATELY THIS HAD LITTLE CHANGE IN THE OVERALL WEATHER
PICTURE AND WAS MORE COSMETIC THAN PHYSICAL. THE REST OF THE
FORECAST IS IN GOOD SHAPE WITH NO CHANGES.
PREVIOUS DISCUSSION AS OF 634 AM EST WEDNESDAY...SFC-850MB RIDGE
AXIS CENTERED ALONG THE NEW ENGLAND COAST BRINGING A CHILLY
MORNING TO VALLEY LOCATIONS...BUT ALREADY SEEING STRONG WARMING
ALOFT WITH 850MB TEMPS AROUND +6C AT BTV AND +9C ACROSS ST.
LAWRENCE COUNTY NY PER 10Z RUC ANALYSIS. EVIDENCE OF THIS IN THE
SFC OBSERVATIONS WITH 11Z READINGS OF 12F AT KSLK...BUT 37F ATOP
WHITEFACE MTN WITH 35KT SWLY WINDS. ALSO - AFTER A LOW OF 25F
AROUND MIDNIGHT - BTV HAS CLIMBED TO 37F AT 11Z AIDED BY VALLEY
CHANNELED SOUTHERLY FLOW OF 10-12KTS. 2-M TEMPS WILL CLIMB
RELATIVELY QUICKLY AREAWIDE AFTER SUNRISE AS SOUTHERLY RETURN FLOW
INCREASES ON WRN PERIPHERY OF THE ANTICYCLONE AND AS RADIATIONAL
INVERSIONS BREAK.
SOUTHERLY WINDS REACH 10-20 MPH THIS AFTN WITH GUSTS TO 25-30
MPH...ESPECIALLY IN THE CHAMPLAIN VALLEY WITH CHANNELED FLOW. WILL
SEE A GRADUAL INCREASE IN MID-UPR CLOUDS THIS AFTN ASSOCIATED WITH
HIGHLY AMPLIFIED AND SLOW MOVING 500MB TROUGH ACROSS THE CENTRAL
PLAINS STATES. DESPITE A BIT OF FILTERED SUN...W/ 925MB TEMPS
MODERATING TO AROUND +6C THIS AFTN AND GOOD LOW-LEVEL MIXING
SHOULD SEE HIGHS REACHING 5 TO 8 DEG WARMER THAN YESTERDAY...AND
GENERALLY IN THE UPR 40S TO LOWER 50S IN VALLEY LOCATIONS. WARMEST
READINGS LIKELY IN WRN ST. LAWRENCE COUNTY NY; LOCALLY IN THE MID
50S.
TEMPERATURES WILL NOT FALL MUCH TONIGHT WITH CONTINUED SLY
GRADIENT FLOW KEEPING SFC WINDS 10-20 MPH WITH GUSTS 25-35 MPH IN
THE CHAMPLAIN VALLEY. 925MB WINDS REACH 55KTS BY 08Z ACROSS THE
CHAMPLAIN VALLEY...SO WILL BE QUITE WINDY ACROSS THE RIDGE TOPS.
MAY SEE SOME LOCALIZED SURFACE GUSTS TO 40 MPH IN THE CHAMPLAIN
VALLEY LATE TONIGHT...BUT RELATIVELY STABLE CONDITIONS BELOW THE
LOW-LEVEL JET SHOULD KEEP GUSTS FROM REACHING MUCH HIGHER.
LOOKING AT LOW TEMPS MAINLY IN THE LOW-MID 40S WEST OF THE GREEN
MTNS...AND LOCALLY UPR 30S EAST OF THE GREENS. WILL SEE A
CONTINUED INCREASE IN CLOUD COVER...WITH POSSIBLE STRATUS LAYER
SPREADING NWD INTO THE REGION DURING THE OVERNIGHT HRS AS WELL.
IT APPEARS MOST OF THE PRECIPITATION WILL HOLD OFF UNTIL DURING
THE DAY THURSDAY INCLUDED JUST A SLIGHT CHANCE OF A PRE-DAWN
SHOWER ACROSS THE ADIRONDACKS AND ST. LAWRENCE COUNTY NY.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH FRIDAY/...
AS OF 305 AM EST WEDNESDAY... THIS PERIOD WILL BE A
TRANSITION FROM STRONG RIDGE TO DEVELOPING MID/UPPER LEVEL TROUGH
ASSOCIATED WITH COLD FRONT AND DIGGING SHORT WAVE ENERGY OVER THE
GREAT LAKES. INITIAL 5H VORT APPROACHES OUR WESTERN CWA AROUND 12Z
THURSDAY ALONG WITH A RIBBON OF ENHANCED 850 TO 500MB MOISTURE AND
PW VALUES APPROACHING 1.0". EXPECT SHOWERS TO DEVELOP ACROSS
NORTHERN NEW YORK BETWEEN 12Z AND 15Z...THEN SLOWLY SHIFT EAST INTO
THE CHAMPLAIN VALLEY AROUND 18Z...AND INTO EASTERN VT BY SUNSET. THE
ECMWF CONTINUES TO SHOW SHOWERS PERSISTING OVERNIGHT ACROSS
CHAMPLAIN VALLEY AND CENTRAL/EASTERN VT AS ADDITIONAL MOISTURE
ADVECTION OCCURS AHEAD OF BOUNDARY ASSOCIATED WITH LOW LEVEL JET OF
50 KNOTS. SOUNDINGS SHOW LIMITED MIXING OF LOW LEVEL JET TO THE
SURFACE ON THURSDAY...WITH BEST CHANCE OF WITNESS A FEW GUSTS
BETWEEN 35 AND 40 MPH ACROSS THE ALIGNED SOUTH TO NORTH VALLEYS AND
OVER THE EXPOSED HIGHER TERRAIN. GIVEN THE STRONG 850MB TO 925MB
WIND FIELD EXPECT SOME TERRAIN DRIVEN EFFECTS TO THE QPF ACROSS OUR
REGION. HIGHEST QPF VALUES OF AN INCH WILL OCCUR ACROSS THE
MOUNTAINS OF CENTRAL/EASTERN VT AND PARTS OF THE EASTERN DACKS WITH
A 0.25 TO 0.75 IN THE SAINT LAWRENCE...CHAMPLAIN..AND PARTS OF THE
CT RIVER VALLEYS. PROGGED 850MB TEMPS PEAK BETWEEN 6-8C AHEAD OF
BOUNDARY ON THURSDAY...BUT CLOUDS/PRECIP WILL LIMIT MIXING. THINKING
HIGHS WILL RANGE FROM THE MID 40S MTNS TO MID/UPPER 50S WARMER
VALLEY LOCATIONS. IF SOME SUN DEVELOPS AHEAD OF RAIN ACROSS THE
CHAMPLAIN VALLEY TEMPERATURES COULD BRIEFLY REACH THE LOWER 60S WITH
BREEZY SOUTHERLY WINDS ON THURSDAY.
ON FRIDAY OUR FORECAST AREA IS UNDER MODERATE LOW LEVEL COLD AIR
ADVECTION AS SHORT WAVE RACES TOWARD NORTHERN MAINE. DEEP DRY SLOT
WITH PWS FALLING BETWEEN 0.25 AND 0.33 DEVELOPS ACROSS OUR CWA BY
18Z...BUT PLENTY OF MOISTURE TRAPPED BELOW SUBSIDENCE INVERSION WILL
RESULT IN MOSTLY CLOUDY SKIES WITH CLEARING IN THE AFTERNOON. ECMWF
STILL SHOWS SOME LINGERING SHOWERS WHICH COULD END AS A FEW WET SNOW
FLAKES ACROSS THE HIGHER TERRAIN OF CENTRAL/EASTERN VT ON FRIDAY
MORNING BETWEEN 12Z-15Z. TEMPERATURES WILL REMAIN MAINLY IN THE
MID/UPPER 30S MOUNTAINS TO MID/UPPER 40S VALLEYS ON FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 305 AM EST WEDNESDAY...WEAK SURFACE RIDGE
BUILDS ACROSS NORTHERN NY ON FRIDAY NIGHT WITH CLEAR SKIES AND LIGHT
WINDS. TEMPERATURES WILL COOL INTO THE TEENS IN THE DEEPER MOUNTAIN
VALLEYS AND MID 20S IN THE CHAMPLAIN VALLEY. IF MORE CLOUDS ARE
PRESENT THAN EXPECTED...TEMPERATURES COULD BE 2 TO 5 DEGREES WARMER.
QUIET WEATHER IS EXPECTED SATURDAY WITH NEAR NORMAL TEMPERATURES.
NEXT POTENT SHORT WAVE ENERGY AND ASSOCIATED TROUGH IMPACT OUR CWA
ON SUNDAY. AS WE THOUGHT YESTERDAY...THE SURFACE LOW PRES TRACK AND
ASSOCIATED CLOSED 5H/7H CIRCULATION IS TRACKING TO OUR NORTH AND
REMAINS FAIRLY PROGRESSIVE IN THE FAST WESTERLY FLOW ALOFT. THIS
WILL LIMIT DEEP MOISTURE ADVECTION ON THE BACKSIDE AND RESULT IN
MAINLY TERRAIN DRIVEN SNOW SHOWERS ON SUNDAY. HOWEVER...GIVEN THE
EXTREMELY STRONG DYNAMICS OF THE SYSTEM AND TIMING OF SECONDARY
SURGE OF COLD AIR DURING THE LATE MORNING/EARLY AFTERNOON...THINKING
A FEW HEAVIER CONVECTION RAIN AND SNOW SHOWERS WILL BE
POSSIBLE...ESPECIALLY OVER THE MOUNTAINS. THIS SYSTEM HAS THE
POTENTIAL TO PRODUCE A BURST OF A FEW INCHES OF SNOW IN A SHORT
PERIOD OF TIME. BY 00Z MONDAY PROGGED 850MB TEMPS DROP TO -8C WITH
925MB TEMPS BETWEEN -2C AND -4C...WHICH WILL RESULT SNOW LEVELS NEAR
THE VALLEY FLOOR. HOWEVER...MOISTURE WILL BE QUICKLY LIFTING NORTH
OF OUR CWA AND MAINLY CONFINED TO THE UPSLOPE REGIONS OF THE
NORTHERN DACKS AND CENTRAL/NORTHERN GREEN MOUNTAINS. ANY LEFTOVER
SNOW SHOWER ACTIVITY WILL DISSIPATE BY 06Z MONDAY WITH MOISTURE
QUICKLY DISSIPATING. EARLY INDICATIONS WOULD BE FOR SEVERAL INCHES
LIKELY IN THE MOUNTAINS ABOVE 2000 FEET WITH 4 OR 5 INCHES POSSIBLE
NEAR THE SUMMIT BY SUNDAY EVENING WITH A DUSTING TO 2 INCHES BETWEEN
1000 AND 2000 FEET. TEMPERATURES ON SUNDAY WILL RANGE FROM THE LOWER
30S MOUNTAIN TOWNS TO LOWER 40S WARMER VALLEYS. EXPECT MID WINTER
CONDITIONS ON MOUNTAIN SUMMITS ON SUNDAY WITH BLUSTERY WINDS AND
AREAS OF SNOW SHOWERS.
MID/UPPER LEVEL TROUGH CONTINUES FOR EARLY NEXT WEEK AS SURFACE
RIDGE OF HIGH PRESSURE BUILDS INTO OUR CWA. THIS WILL RESULT IN
DRYING CONDITIONS WITH BELOW NORMAL TEMPERATURES FOR MONDAY AND
TUESDAY. A FEW LINGERING LIGHT MOUNTAIN SNOW FLURRIES ARE POSSIBLE
WITH TEMPERATURES MAINLY IN THE MID/UPPER 20S TO LOWER 40S.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 12Z THURSDAY...VFR THROUGH 00Z THU...THEN POTENTIAL MVFR
STRATUS DEVELOPING FROM SOUTH TO NORTH DURING THE OVERNIGHT
PERIOD. CLEAR SKIES EARLY TO SLOWLY GIVE WAY TO THIN HIGH CLOUDS
FROM 20-25KFT AGL, WHICH WILL TEND TO THICKEN AFTER 18Z
WEDNESDAY. WINDS GENERALLY VARIABLE AND LESS THAN 6 KNOTS AT MOST
TERMINALS THROUGH 12-13Z WEDNESDAY...THEN BECOMING SOUTH 10-15
KTS WITH GUSTS TO 20 KTS THIS AFTN. ALREADY 11KTS AT BTV WITH
VALLEY CHANNELING AT 11Z. LOCAL GUSTS TO 30 KTS EXPECTED AT BTV
TONIGHT. JUST A SLIGHT CHANCE OF -SHRA AT KMSS/KSLK DURING THE
PRE- DAWN HRS THURSDAY. INCREASING LOW-LEVEL JET TONIGHT BRINGS
PROSPECTS FOR LLWS...BEGINNING AT KSLK AT 19/00Z CENTERED AROUND
2KFT...AND AT MPV BY 06Z.
OUTLOOK 12Z THURSDAY THROUGH SATURDAY...WILL SEE INCREASING SOUTH
WINDS DURING THURSDAY AM AS PRESSURE GRADIENT STRENGTHENS BETWEEN
DEPARTING SFC HIGH PRESSURE AND FRONTAL SYSTEM APPROACHING FROM
THE GREAT LAKES AND OHIO VALLEY. GUSTS 25-40 KNOTS POSSIBLE EARLY
THURSDAY MORNING...HIGHEST AT KBTV WITH CHANNELED FLOW IN THE
CHAMPLAIN VALLEY. PERIODS OF MVFR CONDITIONS EXPECTED THURSDAY
AFTERNOON INTO THURSDAY NIGHT WITH LIGHT TO MODERATE RAINFALL.
TRENDING BACK TO VFR FOR FRI/SAT.
&&
.MARINE...
STRONG SOUTHERLY WINDS AHEAD OF APPROACHING TROUGH AND ASSOCIATED
COLD FRONT WILL MOVE THROUGH THE CHAMPLAIN VALLEY TODAY AND
PERSIST THROUGH THURSDAY AFTERNOON. EXPECT WINDS TO BE 15-25 KNOTS
TO TOADY AND INCREASING TOMORROW TO 20-30 KNOTS BEFORE WEAKENING
TOMORROW EVENING.
&&
.EQUIPMENT...
AS OF 650 PM EST MONDAY...FOR YOUR INFORMATION...THE AUTOMATED
SURFACE OBSERVING SYSTEM (ASOS) AT THE MORRISVILLE-STOWE STATE
AIRPORT (KMVL) IN MORRISVILLE VERMONT WILL BE OUT OF SERVICE FOR A
FEW DAYS THIS WEEK...AS IT IS BEING PHYSICALLY RELOCATED TO
ANOTHER LOCATION ON THE AIRPORT GROUNDS. THUS...ONLY THE ALTIMETER
SETTING WILL BE AVAILABLE FROM THIS SITE. THERE WILL BE NO
TEMPERATURE...DEW POINT...SURFACE WIND...PRESENT WEATHER AND
CEILING BEING REPORTED UNTIL AFTER THE ASOS HAS BEEN RELOCATED.
FOR AVIATION INTERESTS...THE FAA ALREADY HAS A NOTAM OUT ABOUT THE
ASOS OUTAGE AT KMVL.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/DEAL
SHORT TERM...TABER
LONG TERM...TABER
AVIATION...BANACOS
MARINE...
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
836 AM EST WED NOV 18 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER NEW ENGLAND THROUGH
TODAY...BRINGING DRY WEATHER WITH TEMPERATURES MODERATING INTO THE
UPPER 40S TO LOWER 50S THIS AFTERNOON. A FRONTAL SYSTEM
APPROACHING FROM THE GREAT LAKES AND OHIO RIVER VALLEY WILL BRING
INCREASINGLY WINDY AND MILD CONDITIONS FOR WEDNESDAY NIGHT INTO
THURSDAY. THE APPROACHING FRONT WILL ALSO BRING A PERIOD OF LIGHT
TO MODERATE RAIN TO NORTHERN NEW YORK AND VERMONT...MAINLY THURSDAY
AFTERNOON INTO THURSDAY NIGHT. SLIGHTLY COOLER WEATHER IS EXPECTED
FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 634 AM EST WEDNESDAY...SFC-850MB RIDGE AXIS CENTERED ALONG
THE NEW ENGLAND COAST BRINGING A CHILLY MORNING TO VALLEY
LOCATIONS...BUT ALREADY SEEING STRONG WARMING ALOFT WITH 850MB
TEMPS AROUND +6C AT BTV AND +9C ACROSS ST. LAWRENCE COUNTY NY PER
10Z RUC ANALYSIS. EVIDENCE OF THIS IN THE SFC OBSERVATIONS WITH
11Z READINGS OF 12F AT KSLK...BUT 37F ATOP WHITEFACE MTN WITH 35KT
SWLY WINDS. ALSO - AFTER A LOW OF 25F AROUND MIDNIGHT - BTV HAS
CLIMBED TO 37F AT 11Z AIDED BY VALLEY CHANNELED SOUTHERLY FLOW OF
10-12KTS. 2-M TEMPS WILL CLIMB RELATIVELY QUICKLY AREAWIDE AFTER
SUNRISE AS SOUTHERLY RETURN FLOW INCREASES ON WRN PERIPHERY OF THE
ANTICYCLONE AND AS RADIATIONAL INVERSIONS BREAK.
SOUTHERLY WINDS REACH 10-20 MPH THIS AFTN WITH GUSTS TO 25-30
MPH...ESPECIALLY IN THE CHAMPLAIN VALLEY WITH CHANNELED FLOW. WILL
SEE A GRADUAL INCREASE IN MID-UPR CLOUDS THIS AFTN ASSOCIATED WITH
HIGHLY AMPLIFIED AND SLOW MOVING 500MB TROUGH ACROSS THE CENTRAL
PLAINS STATES. DESPITE A BIT OF FILTERED SUN...W/ 925MB TEMPS
MODERATING TO AROUND +6C THIS AFTN AND GOOD LOW-LEVEL MIXING
SHOULD SEE HIGHS REACHING 5 TO 8 DEG WARMER THAN YESTERDAY...AND
GENERALLY IN THE UPR 40S TO LOWER 50S IN VALLEY LOCATIONS. WARMEST
READINGS LIKELY IN WRN ST. LAWRENCE COUNTY NY; LOCALLY IN THE MID
50S.
TEMPERATURES WILL NOT FALL MUCH TONIGHT WITH CONTINUED SLY
GRADIENT FLOW KEEPING SFC WINDS 10-20 MPH WITH GUSTS 25-35 MPH IN
THE CHAMPLAIN VALLEY. 925MB WINDS REACH 55KTS BY 08Z ACROSS THE
CHAMPLAIN VALLEY...SO WILL BE QUITE WINDY ACROSS THE RIDGE TOPS.
MAY SEE SOME LOCALIZED SURFACE GUSTS TO 40 MPH IN THE CHAMPLAIN
VALLEY LATE TONIGHT...BUT RELATIVELY STABLE CONDITIONS BELOW THE
LOW-LEVEL JET SHOULD KEEP GUSTS FROM REACHING MUCH HIGHER.
LOOKING AT LOW TEMPS MAINLY IN THE LOW-MID 40S WEST OF THE GREEN
MTNS...AND LOCALLY UPR 30S EAST OF THE GREENS. WILL SEE A
CONTINUED INCREASE IN CLOUD COVER...WITH POSSIBLE STRATUS LAYER
SPREADING NWD INTO THE REGION DURING THE OVERNIGHT HRS AS WELL.
IT APPEARS MOST OF THE PRECIPITATION WILL HOLD OFF UNTIL DURING
THE DAY THURSDAY INCLUDED JUST A SLIGHT CHANCE OF A PRE-DAWN
SHOWER ACROSS THE ADIRONDACKS AND ST. LAWRENCE COUNTY NY.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 305 AM EST WEDNESDAY... THIS PERIOD WILL BE A
TRANSITION FROM STRONG RIDGE TO DEVELOPING MID/UPPER LEVEL TROUGH
ASSOCIATED WITH COLD FRONT AND DIGGING SHORT WAVE ENERGY OVER THE
GREAT LAKES. INITIAL 5H VORT APPROACHES OUR WESTERN CWA AROUND 12Z
THURSDAY ALONG WITH A RIBBON OF ENHANCED 850 TO 500MB MOISTURE AND
PW VALUES APPROACHING 1.0". EXPECT SHOWERS TO DEVELOP ACROSS
NORTHERN NEW YORK BETWEEN 12Z AND 15Z...THEN SLOWLY SHIFT EAST INTO
THE CHAMPLAIN VALLEY AROUND 18Z...AND INTO EASTERN VT BY SUNSET. THE
ECMWF CONTINUES TO SHOW SHOWERS PERSISTING OVERNIGHT ACROSS
CHAMPLAIN VALLEY AND CENTRAL/EASTERN VT AS ADDITIONAL MOISTURE
ADVECTION OCCURS AHEAD OF BOUNDARY ASSOCIATED WITH LOW LEVEL JET OF
50 KNOTS. SOUNDINGS SHOW LIMITED MIXING OF LOW LEVEL JET TO THE
SURFACE ON THURSDAY...WITH BEST CHANCE OF WITNESS A FEW GUSTS
BETWEEN 35 AND 40 MPH ACROSS THE ALIGNED SOUTH TO NORTH VALLEYS AND
OVER THE EXPOSED HIGHER TERRAIN. GIVEN THE STRONG 850MB TO 925MB
WIND FIELD EXPECT SOME TERRAIN DRIVEN EFFECTS TO THE QPF ACROSS OUR
REGION. HIGHEST QPF VALUES OF AN INCH WILL OCCUR ACROSS THE
MOUNTAINS OF CENTRAL/EASTERN VT AND PARTS OF THE EASTERN DACKS WITH
A 0.25 TO 0.75 IN THE SAINT LAWRENCE...CHAMPLAIN..AND PARTS OF THE
CT RIVER VALLEYS. PROGGED 850MB TEMPS PEAK BETWEEN 6-8C AHEAD OF
BOUNDARY ON THURSDAY...BUT CLOUDS/PRECIP WILL LIMIT MIXING. THINKING
HIGHS WILL RANGE FROM THE MID 40S MTNS TO MID/UPPER 50S WARMER
VALLEY LOCATIONS. IF SOME SUN DEVELOPS AHEAD OF RAIN ACROSS THE
CHAMPLAIN VALLEY TEMPERATURES COULD BRIEFLY REACH THE LOWER 60S WITH
BREEZY SOUTHERLY WINDS ON THURSDAY.
ON FRIDAY OUR FORECAST AREA IS UNDER MODERATE LOW LEVEL COLD AIR
ADVECTION AS SHORT WAVE RACES TOWARD NORTHERN MAINE. DEEP DRY SLOT
WITH PWS FALLING BETWEEN 0.25 AND 0.33 DEVELOPS ACROSS OUR CWA BY
18Z...BUT PLENTY OF MOISTURE TRAPPED BELOW SUBSIDENCE INVERSION WILL
RESULT IN MOSTLY CLOUDY SKIES WITH CLEARING IN THE AFTERNOON. ECMWF
STILL SHOWS SOME LINGERING SHOWERS WHICH COULD END AS A FEW WET SNOW
FLAKES ACROSS THE HIGHER TERRAIN OF CENTRAL/EASTERN VT ON FRIDAY
MORNING BETWEEN 12Z-15Z. TEMPERATURES WILL REMAIN MAINLY IN THE
MID/UPPER 30S MOUNTAINS TO MID/UPPER 40S VALLEYS ON FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 305 AM EST WEDNESDAY...WEAK SURFACE RIDGE
BUILDS ACROSS NORTHERN NY ON FRIDAY NIGHT WITH CLEAR SKIES AND LIGHT
WINDS. TEMPERATURES WILL COOL INTO THE TEENS IN THE DEEPER MOUNTAIN
VALLEYS AND MID 20S IN THE CHAMPLAIN VALLEY. IF MORE CLOUDS ARE
PRESENT THAN EXPECTED...TEMPERATURES COULD BE 2 TO 5 DEGREES WARMER.
QUIET WEATHER IS EXPECTED SATURDAY WITH NEAR NORMAL TEMPERATURES.
NEXT POTENT SHORT WAVE ENERGY AND ASSOCIATED TROUGH IMPACT OUR CWA
ON SUNDAY. AS WE THOUGHT YESTERDAY...THE SURFACE LOW PRES TRACK AND
ASSOCIATED CLOSED 5H/7H CIRCULATION IS TRACKING TO OUR NORTH AND
REMAINS FAIRLY PROGRESSIVE IN THE FAST WESTERLY FLOW ALOFT. THIS
WILL LIMIT DEEP MOISTURE ADVECTION ON THE BACKSIDE AND RESULT IN
MAINLY TERRAIN DRIVEN SNOW SHOWERS ON SUNDAY. HOWEVER...GIVEN THE
EXTREMELY STRONG DYNAMICS OF THE SYSTEM AND TIMING OF SECONDARY
SURGE OF COLD AIR DURING THE LATE MORNING/EARLY AFTERNOON...THINKING
A FEW HEAVIER CONVECTION RAIN AND SNOW SHOWERS WILL BE
POSSIBLE...ESPECIALLY OVER THE MOUNTAINS. THIS SYSTEM HAS THE
POTENTIAL TO PRODUCE A BURST OF A FEW INCHES OF SNOW IN A SHORT
PERIOD OF TIME. BY 00Z MONDAY PROGGED 850MB TEMPS DROP TO -8C WITH
925MB TEMPS BETWEEN -2C AND -4C...WHICH WILL RESULT SNOW LEVELS NEAR
THE VALLEY FLOOR. HOWEVER...MOISTURE WILL BE QUICKLY LIFTING NORTH
OF OUR CWA AND MAINLY CONFINED TO THE UPSLOPE REGIONS OF THE
NORTHERN DACKS AND CENTRAL/NORTHERN GREEN MOUNTAINS. ANY LEFTOVER
SNOW SHOWER ACTIVITY WILL DISSIPATE BY 06Z MONDAY WITH MOISTURE
QUICKLY DISSIPATING. EARLY INDICATIONS WOULD BE FOR SEVERAL INCHES
LIKELY IN THE MOUNTAINS ABOVE 2000 FEET WITH 4 OR 5 INCHES POSSIBLE
NEAR THE SUMMIT BY SUNDAY EVENING WITH A DUSTING TO 2 INCHES BETWEEN
1000 AND 2000 FEET. TEMPERATURES ON SUNDAY WILL RANGE FROM THE LOWER
30S MOUNTAIN TOWNS TO LOWER 40S WARMER VALLEYS. EXPECT MID WINTER
CONDITIONS ON MOUNTAIN SUMMITS ON SUNDAY WITH BLUSTERY WINDS AND
AREAS OF SNOW SHOWERS.
MID/UPPER LEVEL TROUGH CONTINUES FOR EARLY NEXT WEEK AS SURFACE
RIDGE OF HIGH PRESSURE BUILDS INTO OUR CWA. THIS WILL RESULT IN
DRYING CONDITIONS WITH BELOW NORMAL TEMPERATURES FOR MONDAY AND
TUESDAY. A FEW LINGERING LIGHT MOUNTAIN SNOW FLURRIES ARE POSSIBLE
WITH TEMPERATURES MAINLY IN THE MID/UPPER 20S TO LOWER 40S.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 12Z THURSDAY...VFR THROUGH 00Z THU...THEN POTENTIAL MVFR
STRATUS DEVELOPING FROM SOUTH TO NORTH DURING THE OVERNIGHT
PERIOD. CLEAR SKIES EARLY TO SLOWLY GIVE WAY TO THIN HIGH CLOUDS
FROM 20-25KFT AGL, WHICH WILL TEND TO THICKEN AFTER 18Z
WEDNESDAY. WINDS GENERALLY VARIABLE AND LESS THAN 6 KNOTS AT MOST
TERMINALS THROUGH 12-13Z WEDNESDAY...THEN BECOMING SOUTH 10-15
KTS WITH GUSTS TO 20 KTS THIS AFTN. ALREADY 11KTS AT BTV WITH
VALLEY CHANNELING AT 11Z. LOCAL GUSTS TO 30 KTS EXPECTED AT BTV
TONIGHT. JUST A SLIGHT CHANCE OF -SHRA AT KMSS/KSLK DURING THE
PRE- DAWN HRS THURSDAY. INCREASING LOW-LEVEL JET TONIGHT BRINGS
PROSPECTS FOR LLWS...BEGINNING AT KSLK AT 19/00Z CENTERED AROUND
2KFT...AND AT MPV BY 06Z.
OUTLOOK 12Z THURSDAY THROUGH SATURDAY...WILL SEE INCREASING SOUTH
WINDS DURING THURSDAY AM AS PRESSURE GRADIENT STRENGTHENS BETWEEN
DEPARTING SFC HIGH PRESSURE AND FRONTAL SYSTEM APPROACHING FROM
THE GREAT LAKES AND OHIO VALLEY. GUSTS 25-40 KNOTS POSSIBLE EARLY
THURSDAY MORNING...HIGHEST AT KBTV WITH CHANNELED FLOW IN THE
CHAMPLAIN VALLEY. PERIODS OF MVFR CONDITIONS EXPECTED THURSDAY
AFTERNOON INTO THURSDAY NIGHT WITH LIGHT TO MODERATE RAINFALL.
TRENDING BACK TO VFR FOR FRI/SAT.
&&
.MARINE...
STRONG SOUTHERLY WINDS AHEAD OF APPROACHING TROUGH AND ASSOCIATED
COLD FRONT WILL MOVE THROUGH THE CHAMPLAIN VALLEY TODAY AND
PERSIST THROUGH THURSDAY AFTERNOON. EXPECT WINDS TO BE 15-25 KNOTS
TO TOADY AND INCREASING TOMORROW TO 20-30 KNOTS BEFORE WEAKENING
TOMORROW EVENING.
&&
.EQUIPMENT...
AS OF 650 PM EST MONDAY...FOR YOUR INFORMATION...THE AUTOMATED
SURFACE OBSERVING SYSTEM (ASOS) AT THE MORRISVILLE-STOWE STATE
AIRPORT (KMVL) IN MORRISVILLE VERMONT WILL BE OUT OF SERVICE FOR A
FEW DAYS THIS WEEK...AS IT IS BEING PHYSICALLY RELOCATED TO
ANOTHER LOCATION ON THE AIRPORT GROUNDS. THUS...ONLY THE ALTIMETER
SETTING WILL BE AVAILABLE FROM THIS SITE. THERE WILL BE NO
TEMPERATURE...DEW POINT...SURFACE WIND...PRESENT WEATHER AND
CEILING BEING REPORTED UNTIL AFTER THE ASOS HAS BEEN RELOCATED.
FOR AVIATION INTERESTS...THE FAA ALREADY HAS A NOTAM OUT ABOUT THE
ASOS OUTAGE AT KMVL.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS
SHORT TERM...TABER
LONG TERM...TABER
AVIATION...BANACOS
MARINE...
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
641 AM EST WED NOV 18 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER NEW ENGLAND THROUGH
TODAY...BRINGING DRY WEATHER WITH TEMPERATURES MODERATING INTO THE
UPPER 40S TO LOWER 50S THIS AFTERNOON. A FRONTAL SYSTEM
APPROACHING FROM THE GREAT LAKES AND OHIO RIVER VALLEY WILL BRING
INCREASINGLY WINDY AND MILD CONDITIONS FOR WEDNESDAY NIGHT INTO
THURSDAY. THE APPROACHING FRONT WILL ALSO BRING A PERIOD OF LIGHT
TO MODERATE RAIN TO NORTHERN NEW YORK AND VERMONT...MAINLY THURSDAY
AFTERNOON INTO THURSDAY NIGHT. SLIGHTLY COOLER WEATHER IS EXPECTED
FOR FRIDAY AND SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 634 AM EST WEDNESDAY...SFC-850MB RIDGE AXIS CENTERED ALONG
THE NEW ENGLAND COAST BRINGING A CHILLY MORNING TO VALLEY
LOCATIONS...BUT ALREADY SEEING STRONG WARMING ALOFT WITH 850MB
TEMPS AROUND +6C AT BTV AND +9C ACROSS ST. LAWRENCE COUNTY NY PER
10Z RUC ANALYSIS. EVIDENCE OF THIS IN THE SFC OBSERVATIONS WITH
11Z READINGS OF 12F AT KSLK...BUT 37F ATOP WHITEFACE MTN WITH 35KT
SWLY WINDS. ALSO - AFTER A LOW OF 25F AROUND MIDNIGHT - BTV HAS
CLIMBED TO 37F AT 11Z AIDED BY VALLEY CHANNELED SOUTHERLY FLOW OF
10-12KTS. 2-M TEMPS WILL CLIMB RELATIVELY QUICKLY AREAWIDE AFTER
SUNRISE AS SOUTHERLY RETURN FLOW INCREASES ON WRN PERIPHERY OF THE
ANTICYCLONE AND AS RADIATIONAL INVERSIONS BREAK.
SOUTHERLY WINDS REACH 10-20 MPH THIS AFTN WITH GUSTS TO 25-30
MPH...ESPECIALLY IN THE CHAMPLAIN VALLEY WITH CHANNELED FLOW. WILL
SEE A GRADUAL INCREASE IN MID-UPR CLOUDS THIS AFTN ASSOCIATED WITH
HIGHLY AMPLIFIED AND SLOW MOVING 500MB TROUGH ACROSS THE CENTRAL
PLAINS STATES. DESPITE A BIT OF FILTERED SUN...W/ 925MB TEMPS
MODERATING TO AROUND +6C THIS AFTN AND GOOD LOW-LEVEL MIXING
SHOULD SEE HIGHS REACHING 5 TO 8 DEG WARMER THAN YESTERDAY...AND
GENERALLY IN THE UPR 40S TO LOWER 50S IN VALLEY LOCATIONS. WARMEST
READINGS LIKELY IN WRN ST. LAWRENCE COUNTY NY; LOCALLY IN THE MID
50S.
TEMPERATURES WILL NOT FALL MUCH TONIGHT WITH CONTINUED SLY
GRADIENT FLOW KEEPING SFC WINDS 10-20 MPH WITH GUSTS 25-35 MPH IN
THE CHAMPLAIN VALLEY. 925MB WINDS REACH 55KTS BY 08Z ACROSS THE
CHAMPLAIN VALLEY...SO WILL BE QUITE WINDY ACROSS THE RIDGE TOPS.
MAY SEE SOME LOCALIZED SURFACE GUSTS TO 40 MPH IN THE CHAMPLAIN
VALLEY LATE TONIGHT...BUT RELATIVELY STABLE CONDITIONS BELOW THE
LOW-LEVEL JET SHOULD KEEP GUSTS FROM REACHING MUCH HIGHER.
LOOKING AT LOW TEMPS MAINLY IN THE LOW-MID 40S WEST OF THE GREEN
MTNS...AND LOCALLY UPR 30S EAST OF THE GREENS. WILL SEE A
CONTINUED INCREASE IN CLOUD COVER...WITH POSSIBLE STRATUS LAYER
SPREADING NWD INTO THE REGION DURING THE OVERNIGHT HRS AS WELL.
IT APPEARS MOST OF THE PRECIPITATION WILL HOLD OFF UNTIL DURING
THE DAY THURSDAY INCLUDED JUST A SLIGHT CHANCE OF A PRE-DAWN
SHOWER ACROSS THE ADIRONDACKS AND ST. LAWRENCE COUNTY NY.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 305 AM EST WEDNESDAY... THIS PERIOD WILL BE A
TRANSITION FROM STRONG RIDGE TO DEVELOPING MID/UPPER LEVEL TROUGH
ASSOCIATED WITH COLD FRONT AND DIGGING SHORT WAVE ENERGY OVER THE
GREAT LAKES. INITIAL 5H VORT APPROACHES OUR WESTERN CWA AROUND 12Z
THURSDAY ALONG WITH A RIBBON OF ENHANCED 850 TO 500MB MOISTURE AND
PW VALUES APPROACHING 1.0". EXPECT SHOWERS TO DEVELOP ACROSS
NORTHERN NEW YORK BETWEEN 12Z AND 15Z...THEN SLOWLY SHIFT EAST INTO
THE CHAMPLAIN VALLEY AROUND 18Z...AND INTO EASTERN VT BY SUNSET. THE
ECMWF CONTINUES TO SHOW SHOWERS PERSISTING OVERNIGHT ACROSS
CHAMPLAIN VALLEY AND CENTRAL/EASTERN VT AS ADDITIONAL MOISTURE
ADVECTION OCCURS AHEAD OF BOUNDARY ASSOCIATED WITH LOW LEVEL JET OF
50 KNOTS. SOUNDINGS SHOW LIMITED MIXING OF LOW LEVEL JET TO THE
SURFACE ON THURSDAY...WITH BEST CHANCE OF WITNESS A FEW GUSTS
BETWEEN 35 AND 40 MPH ACROSS THE ALIGNED SOUTH TO NORTH VALLEYS AND
OVER THE EXPOSED HIGHER TERRAIN. GIVEN THE STRONG 850MB TO 925MB
WIND FIELD EXPECT SOME TERRAIN DRIVEN EFFECTS TO THE QPF ACROSS OUR
REGION. HIGHEST QPF VALUES OF AN INCH WILL OCCUR ACROSS THE
MOUNTAINS OF CENTRAL/EASTERN VT AND PARTS OF THE EASTERN DACKS WITH
A 0.25 TO 0.75 IN THE SAINT LAWRENCE...CHAMPLAIN..AND PARTS OF THE
CT RIVER VALLEYS. PROGGED 850MB TEMPS PEAK BETWEEN 6-8C AHEAD OF
BOUNDARY ON THURSDAY...BUT CLOUDS/PRECIP WILL LIMIT MIXING. THINKING
HIGHS WILL RANGE FROM THE MID 40S MTNS TO MID/UPPER 50S WARMER
VALLEY LOCATIONS. IF SOME SUN DEVELOPS AHEAD OF RAIN ACROSS THE
CHAMPLAIN VALLEY TEMPERATURES COULD BRIEFLY REACH THE LOWER 60S WITH
BREEZY SOUTHERLY WINDS ON THURSDAY.
ON FRIDAY OUR FORECAST AREA IS UNDER MODERATE LOW LEVEL COLD AIR
ADVECTION AS SHORT WAVE RACES TOWARD NORTHERN MAINE. DEEP DRY SLOT
WITH PWS FALLING BETWEEN 0.25 AND 0.33 DEVELOPS ACROSS OUR CWA BY
18Z...BUT PLENTY OF MOISTURE TRAPPED BELOW SUBSIDENCE INVERSION WILL
RESULT IN MOSTLY CLOUDY SKIES WITH CLEARING IN THE AFTERNOON. ECMWF
STILL SHOWS SOME LINGERING SHOWERS WHICH COULD END AS A FEW WET SNOW
FLAKES ACROSS THE HIGHER TERRAIN OF CENTRAL/EASTERN VT ON FRIDAY
MORNING BETWEEN 12Z-15Z. TEMPERATURES WILL REMAIN MAINLY IN THE
MID/UPPER 30S MOUNTAINS TO MID/UPPER 40S VALLEYS ON FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 305 AM EST WEDNESDAY...WEAK SURFACE RIDGE
BUILDS ACROSS NORTHERN NY ON FRIDAY NIGHT WITH CLEAR SKIES AND LIGHT
WINDS. TEMPERATURES WILL COOL INTO THE TEENS IN THE DEEPER MOUNTAIN
VALLEYS AND MID 20S IN THE CHAMPLAIN VALLEY. IF MORE CLOUDS ARE
PRESENT THAN EXPECTED...TEMPERATURES COULD BE 2 TO 5 DEGREES WARMER.
QUIET WEATHER IS EXPECTED SATURDAY WITH NEAR NORMAL TEMPERATURES.
NEXT POTENT SHORT WAVE ENERGY AND ASSOCIATED TROUGH IMPACT OUR CWA
ON SUNDAY. AS WE THOUGHT YESTERDAY...THE SURFACE LOW PRES TRACK AND
ASSOCIATED CLOSED 5H/7H CIRCULATION IS TRACKING TO OUR NORTH AND
REMAINS FAIRLY PROGRESSIVE IN THE FAST WESTERLY FLOW ALOFT. THIS
WILL LIMIT DEEP MOISTURE ADVECTION ON THE BACKSIDE AND RESULT IN
MAINLY TERRAIN DRIVEN SNOW SHOWERS ON SUNDAY. HOWEVER...GIVEN THE
EXTREMELY STRONG DYNAMICS OF THE SYSTEM AND TIMING OF SECONDARY
SURGE OF COLD AIR DURING THE LATE MORNING/EARLY AFTERNOON...THINKING
A FEW HEAVIER CONVECTION RAIN AND SNOW SHOWERS WILL BE
POSSIBLE...ESPECIALLY OVER THE MOUNTAINS. THIS SYSTEM HAS THE
POTENTIAL TO PRODUCE A BURST OF A FEW INCHES OF SNOW IN A SHORT
PERIOD OF TIME. BY 00Z MONDAY PROGGED 850MB TEMPS DROP TO -8C WITH
925MB TEMPS BETWEEN -2C AND -4C...WHICH WILL RESULT SNOW LEVELS NEAR
THE VALLEY FLOOR. HOWEVER...MOISTURE WILL BE QUICKLY LIFTING NORTH
OF OUR CWA AND MAINLY CONFINED TO THE UPSLOPE REGIONS OF THE
NORTHERN DACKS AND CENTRAL/NORTHERN GREEN MOUNTAINS. ANY LEFTOVER
SNOW SHOWER ACTIVITY WILL DISSIPATE BY 06Z MONDAY WITH MOISTURE
QUICKLY DISSIPATING. EARLY INDICATIONS WOULD BE FOR SEVERAL INCHES
LIKELY IN THE MOUNTAINS ABOVE 2000 FEET WITH 4 OR 5 INCHES POSSIBLE
NEAR THE SUMMIT BY SUNDAY EVENING WITH A DUSTING TO 2 INCHES BETWEEN
1000 AND 2000 FEET. TEMPERATURES ON SUNDAY WILL RANGE FROM THE LOWER
30S MOUNTAIN TOWNS TO LOWER 40S WARMER VALLEYS. EXPECT MID WINTER
CONDITIONS ON MOUNTAIN SUMMITS ON SUNDAY WITH BLUSTERY WINDS AND
AREAS OF SNOW SHOWERS.
MID/UPPER LEVEL TROUGH CONTINUES FOR EARLY NEXT WEEK AS SURFACE
RIDGE OF HIGH PRESSURE BUILDS INTO OUR CWA. THIS WILL RESULT IN
DRYING CONDITIONS WITH BELOW NORMAL TEMPERATURES FOR MONDAY AND
TUESDAY. A FEW LINGERING LIGHT MOUNTAIN SNOW FLURRIES ARE POSSIBLE
WITH TEMPERATURES MAINLY IN THE MID/UPPER 20S TO LOWER 40S.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 12Z THURSDAY...VFR THROUGH 00Z THU...THEN POTENTIAL MVFR
STRATUS DEVELOPING FROM SOUTH TO NORTH DURING THE OVERNIGHT
PERIOD. CLEAR SKIES EARLY TO SLOWLY GIVE WAY TO THIN HIGH CLOUDS
FROM 20-25KFT AGL, WHICH WILL TEND TO THICKEN AFTER 18Z
WEDNESDAY. WINDS GENERALLY VARIABLE AND LESS THAN 6 KNOTS AT MOST
TERMINALS THROUGH 12-13Z WEDNESDAY...THEN BECOMING SOUTH 10-15
KTS WITH GUSTS TO 20 KTS THIS AFTN. ALREADY 11KTS AT BTV WITH
VALLEY CHANNELING AT 11Z. LOCAL GUSTS TO 30 KTS EXPECTED AT BTV
TONIGHT. JUST A SLIGHT CHANCE OF -SHRA AT KMSS/KSLK DURING THE
PRE- DAWN HRS THURSDAY. INCREASING LOW-LEVEL JET TONIGHT BRINGS
PROSPECTS FOR LLWS...BEGINNING AT KSLK AT 19/00Z CENTERED AROUND
2KFT...AND AT MPV BY 06Z.
OUTLOOK 12Z THURSDAY THROUGH SATURDAY...WILL SEE INCREASING SOUTH
WINDS DURING THURSDAY AM AS PRESSURE GRADIENT STRENGTHENS BETWEEN
DEPARTING SFC HIGH PRESSURE AND FRONTAL SYSTEM APPROACHING FROM
THE GREAT LAKES AND OHIO VALLEY. GUSTS 25-40 KNOTS POSSIBLE EARLY
THURSDAY MORNING...HIGHEST AT KBTV WITH CHANNELED FLOW IN THE
CHAMPLAIN VALLEY. PERIODS OF MVFR CONDITIONS EXPECTED THURSDAY
AFTERNOON INTO THURSDAY NIGHT WITH LIGHT TO MODERATE RAINFALL.
TRENDING BACK TO VFR FOR FRI/SAT.
&&
.EQUIPMENT...
AS OF 650 PM EST MONDAY...FOR YOUR INFORMATION...THE AUTOMATED
SURFACE OBSERVING SYSTEM (ASOS) AT THE MORRISVILLE-STOWE STATE
AIRPORT (KMVL) IN MORRISVILLE VERMONT WILL BE OUT OF SERVICE FOR A
FEW DAYS THIS WEEK...AS IT IS BEING PHYSICALLY RELOCATED TO
ANOTHER LOCATION ON THE AIRPORT GROUNDS. THUS...ONLY THE ALTIMETER
SETTING WILL BE AVAILABLE FROM THIS SITE. THERE WILL BE NO
TEMPERATURE...DEW POINT...SURFACE WIND...PRESENT WEATHER AND
CEILING BEING REPORTED UNTIL AFTER THE ASOS HAS BEEN RELOCATED.
FOR AVIATION INTERESTS...THE FAA ALREADY HAS A NOTAM OUT ABOUT THE
ASOS OUTAGE AT KMVL.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS
SHORT TERM...TABER
LONG TERM...TABER
AVIATION...BANACOS
EQUIPMENT...WFO BTV
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1229 AM EST WED NOV 18 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE EXTENDING SOUTH INTO THE REGION
WILL SLIDE OFFSHORE TONIGHT. A WEAK WARM FRONT WILL PUSH NORTH
ACROSS THE AREA ON WEDNESDAY. A COLD FRONT WILL APPROACH FROM
THE WEST WEDNESDAY NIGHT THEN CROSS EASTERN NORTH CAROLINA
THURSDAY INTO THURSDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM
THE WEST LATE IN THE WEEK. AN AREA OF LOW PRESSURE WILL LIFT
NORTHEAST OFFSHORE OF THE COAST SATURDAY NIGHT INTO
SUNDAY...FOLLOWED BY HIGH PRESSURE EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1225 AM WED...NO SIGNIF CHANGES. RDR SHOWS SOME SHRA
APPROACHING OBX AND SHLD ARRIVE LATER AND THIS MATCHES FORECAST
WITH SMALL POPS THESE AREAS DEVELOPING BEFORE MORNING.
PREV DISC...HIGH CLOUDINESS CONTINUES TO STREAM EAST FROM
WIDESPREAD CONVECTION NEAR THE MISSISSIPPI VALLEY. LIGHT SHOWERS
THAT WERE OFFSHORE HAVE DISSIPATED BUT LATEST 3KM HRRR MODEL DOES
INDICATE SOME LIGHT SHOWERS MOVING IN FROM OFF THE WATER TOWARD
MORNING AND WILL KEEP SMALL POP IN THE FORECAST. TEMPERATURES
SHOULD LEVEL OFF NEAR CURRENT READINGS IN THE MID 50S INLAND TO
LOWER 60S COAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TODAY/...
AS OF 315 PM TUESDAY...COASTAL TROF/WEAK WARM FRONT WILL LIFT
ACROSS THE AREA AS LOW LEVEL FLOW VEERS SOUTHERLY THROUGH THE DAY.
MODELS AGAIN SUGGEST THAT COASTAL AREAS AND AREAS JUST INLAND WILL
HAVE THE BEST CHANCES FOR SCATTERED, PASSING SHOWERS ON WEDNESDAY,
HOWEVER ANY PRECIP WILL BE LIGHT AND BRIEF PER WEAK FORCING
MECHANISMS. DESPITE PARTLY SUNNY TO MOSTLY CLOUDY SKIES, THE
SOUTHERLY FLOW WILL DRAW IN INCREASING WARMTH WITH HIGHS EXPECTED
WELL INTO THE 70S.
&&
.LONG TERM /TONIGHT THROUGH TUESDAY/...
AS OF 315 PM TUE...COMPARISON OF LATEST GFS AND ECMWF SHOW GOOD
AGREEMENT THROUGH SATURDAY. DIFFERENCES SHOW UP AFTER THAT IN
THEIR HANDLING OF SURFACE AND UPPER FEATURES THROUGH EARLY NEXT
WEEK. CONSENSUS CONTINUES TO FAVOR THE ECMWF.
NO CHANGES MADE TO TIMING OF PRECIP. SHOWERS WILL INCREASE FROM
WEST TO EAST WEDNESDAY NIGHT BECOMING WIDESPREAD ON THURSDAY.
CATEGORICAL POPS ALL AREAS THURSDAY. WILL CONTINUE TO MENTION
SLIGHT CHANCE OF THUNDER. RATHER IMPRESSIVE UPPER DYNAMICS BUT
OVERCAST SKIES AND WIDESPREAD SHOWERS WILL LIMIT INSTABILITY. THE
FRONT MOVES OFF THE COAST THURSDAY NIGHT. TIME SECTIONS AND
FORECAST SOUNDINGS SHOW RAPID DRYING WEST TO EAST. MODELS SHOW A
WEAK FRONT PASSING THROUGH SATURDAY NIGHT BUT LITTLE MOISTURE TO
WORK WITH SO HAVE KEPT FORECAST DRY.
DRY AND CHILLY AIRMASS MOVES IN FOR THE WEEKEND INTO EARLY NEXT
WEEK WITH HIGHS IN THE 50S AND LOWS IN THE 40S FRIDAY NIGHT AND
SATURDAY NIGHT. COLDEST NIGHT WILL BE SUNDAY NIGHT/MONDAY MORNING
WITH LOWS IN THE LOWER 30S COASTAL PLAIN TO UPPER 30S SOUTH COAST.
LOW TEMPS WILL MODERATE A BIT MONDAY NIGHT/TUESDAY MORNING TO MID
30S WEST TO LOWER 40S SOUTH COAST.
&&
.AVIATION /05Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1220 AM WED...MAY BE A PERIOD OF MVFR OR IFR CIGS OVER NW
TIER LATER TONIGHT AND EARLY WED MORN AS HIGH RES MDLS SHOWING
STRATUS INCREASING THESE AREAS. OTHERWISE MAINLY VFR REST OF
REGION WITH CLOUDS INCREASING. SOME WDLY SCT SHRA EXPECTED OVER
REGION TODAY AS CSTL TRF/WARM FRONT MOVES INLAND BUT GIVEN LIMITED
CVRG WILL NOT ADD TO TAFS...EXPECT CIGS IN THE VFR RANGE. RAIN
WILL BE INCREASING FROM W TO E TONIGHT AFTER 06Z AHEAD OF A COLD
FRONT WITH SUB VFR CIGS/VSBYS EXPECTED TO DEVELOP INLAND LATE.
LONG TERM /THU THROUGH SUN/...
AS OF 315 PM TUE...SUB-VFR CONDITIONS THROUGH THURSDAY NIGHT AS
COLD FRONT MOVES THROUGH. SHOWERS WILL INCREASE IN COVERAGE WEST
TO EAST WEDNESDAY NIGHT AND WILL BE WIDESPREAD THURSDAY. ISOLATED
THUNDER POSSIBLE MAINLY THURSDAY AFTERNOON. FRONT WILL MOVE OFF
THE COAST THURSDAY NIGHT WITH SHOWERS ENDING. VFR/DRY FRIDAY
THROUGH SUNDAY.
&&
.MARINE...
SHORT TERM /THROUGH WEDNESDAY/...
AS OF 1225 AM WED...NO CHANGES WITH SCA CONDITIONS ALREADY
OCCURRING CNTRL AND NRN WTRS AND SHLD DEVELOP SRN WTRS THIS MORN.
PREV DISC...GUSTY EAST TO NORTHEAST WINDS HAS PUSHED SEAS UP TO
AROUND 6 FEET OVER THE NORTHERN WATERS AND HAVE CHANGED START TIME
FOR SMALL CRAFT ADVISORY OVER THE NORTHERN THREE LEGS TO THE
CURRENT TIME. WINDS WILL CONTINUE IN THE 15 TO 25 KNOT RANGE OVER
THE COASTAL WATERS AND SOUNDS OVERNIGHT. THESE INCREASING WINDS
WILL LEAD TO SEAS BUILDING FROM 4 TO 7 FEET TONIGHT TO 5 TO 8 FEET
WED.
LONG TERM /WED NIGHT THROUGH SUN/
AS OF 315 PM TUE...SMALL CRAFT CONDITIONS ONGOING AT THE BEGINNING
OF THE LONG TERM WILL CONTINUE INTO SATURDAY MORNING. MADE ONLY
MINOR ADJUSTMENTS TO ENDING TIME OF ADVISORIES. SOUTHEAST WIND
WEDNESDAY NIGHT VEERS FURTHER TO SOUTH ON THURSDAY AHEAD OF
APPROACHING COLD FRONT. THE FRONT WILL MOVE QUICKLY OFF THE COAST
THURSDAY NIGHT WITH A RAPID SHIFT TO WEST...THEN FURTHER TO NORTH
ON FRIDAY. NORTHERLY FLOW WILL CONTINUE INTO SUNDAY. SEAS WILL
PEAK ON FRIDAY AT 7-10 FEET NORTH OF OCRACOKE AND 4-8 FEET SOUTH.
SLOWLY IMPROVING CONDITIONS FORECAST THIS WEEKEND AS HIGH PRESSURE
BUILDS TO THE NORTHWEST. A WEAK FRONT WILL PASS THROUGH SATURDAY
NIGHT BUT LITTLE IF ANY EFFECT ON MARINE CONDITIONS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST SATURDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 10 AM EST
SATURDAY FOR AMZ156-158.
SMALL CRAFT ADVISORY UNTIL 10 AM EST SATURDAY FOR AMZ150.
&&
$$
SYNOPSIS...BTC
NEAR TERM...RF/CTC
SHORT TERM...BTC
LONG TERM...HSA
AVIATION...RF/HSA
MARINE...RF/BTC/CTC/HSA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1244 PM CST WED NOV 18 2015
.UPDATE...
ISSUED AT 1236 PM CST WED NOV 18 2015
BACK EDGE OF RAIN OVER WESTERN MN BEGINNING TO SHIFT EAST WHILE
SKINNY BAND OF -RA OVER THE FAR WESTERN FA SLOWLY SPREADING EAST.
MADE SOME MINOR POP ADJUSTMENTS BUT OVERALL NOT SIGNIFICANT.
TEMPERATURES JUST AHEAD OF COLD FRONT BUMP UP CLOSE TO AND ABOVE
40 SO MAIN QUESTION IS HOW FAR EAST THESE WARMER TEMPERATURES GET
BEFORE BECOMING OVER RUN BY COLD FRONT. OVERALL MADE MINIMAL
CHANGES TO MAXIMUM TEMPERATURES WITH UNCERTAINTY.
UPDATE ISSUED AT 950 AM CST WED NOV 18 2015
RAIN BAND SETTING UP ACROSS WESTERN MN LINING UP WELL WITH CURRENT
POPS. WEAKENING BAND PUSHING INTO THE FAR NW FA ASSOCIATED WITH
MID LEVEL CLOUDS AND NOT LIKELY REACHING THE GROUND. SURFACE
TEMPERATURES SUBFREEZING HOWEVER GUIDANCE WARMS ROAD SURFACES
ABOVE FREEZING OVER THE NEXT HOUR. CANNOT RULE OUT A BRIEF SPIT
HOWEVER NOT LIKELY TO CAUSE ANY TRAVEL IMPACTS. DID LOWER POPS
SLIGHTLY OVER THE WESTERN AREAS THROUGH NOON. NO OTHER CHANGES.
UPDATE ISSUED AT 707 AM CST WED NOV 18 2015
BAND OF PRECIP IN CNTRL ND ATTM MINOT TO BISMARCK MOVING EAST. CAM
MODELS INSIST IT WILL FALL APART AS IT MOVES EAST...BUT UNSURE SO
WILL MAINTAIN A LOW POP AS IT MOVES EAST. MORE TRACE EVENT STUFF.
ISSUE IS TEMPS AS CLOUDS WILL COME IN WITH THE PRECIP AND WARM UP
ENOUGH TO BE MOSTLY LIQUID BUT ISSUE IS NEXT 1-2 HOURS AS PRECIP
ARRIVES INTO FAR NW FCST AREA AND MAY DO SO IN TIME BEFORE TEMPS
RISE. WILL MENTION FZRA/RA IN FAR NW FCST AREA FOR THIS AT 15Z
THEN JUST -RA 16Z ONWARD. WILL NEED TO WATCH. O/W NO CHANGES.
VARIOUS 06Z MODEL DATA SUPPORTS PREV WIND IDEAS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
MODELS REMAIN PRETTY CONSISTENT OVERALL...BUT DETAILS ON WIND AND
SNOW ARE TOUGH. FIRST OFF...AREA OF RAIN ASSOC WITH MAIN UPPER LOW
IN KANSAS LIFTING NORTHEAST IS A BIT FARTHER EAST THAN EARLIER
PROGGED. THUS DID PUSH THE HIGH POPS A BIT EAST AND EAST OF THE
RRV. CLOUD-CLEAR LINE FROM LAST EVENING HOLDING AS EXPECTED
HALLOCK-GRAND FORKS-FORMAN ND. SOME FOG NOTICED ESP EAST OF THE
RRV ON THE WRN FLANK OF THE LOW CLOUDS WITH SEVERAL SITES FROM
ROSEAU TO FOSSTON TO DTL DOWN 1/2 MILE OR LESS. ADDED AREAS OF FOG
THIS AREA THRU THE MORNING.
FOR THE DAY...THE RAIN WILL SPREAD UP THRU THE ERN FCST
AREA...WHILE CLOUDS INCREASE FROM THE WEST. CLEAR AREA OVER WRN
FCST AREA WHERE TEMPS DROPPED INTO THE LOW 20S WILL WARM UP AS
THERE IS A PERIOD OF SOUTHWEST WIND AHD OF THE FRONT AND COOLER
AIR. HRRR INDICATES A BAND OF LIGHT PRECIP ALONG THE COLD FRONT
ENTERING DVL REGION EARLY AFTN AND INTO RRV LATE AFTN. RE-WORKED
SOME POPS FOR THIS. MORE GLOBAL MODELS WEAKEN THIS. RADAR OUT WEST
SHOWS PCPN VERY LIGHT AND SCATTERED AND THUS HAVE ONLY LOW POPS
FOR ANY AFTN PRECIP IN ERN ND.
ISSUE IS WIND. IT DOES APPEAR THAT JUST BEHIND THE FRONT FOR A FEW
HOURS THERE IS ENOUGH PRESSURE RISE, 850 MB COLD ADVECTION AND
STEEP LOW LEVEL LAPSE RATE TO BRING SOME OF THE 850 MB WINDS
(55-60 KT) TO THE SFC IN CNTRL ND AND WRN FCST AREA VERY LATE
AFTN-EVE. AS THESE HIGHER WINDS ALOFT MOVE INTO THE RED RIVER
VALLEY TONIGHT FEEL FULL MIXING WILL NOT BE REALIZED AS MAIN CORE
OF PRESSURE RISES CONTINUES TO DROP SOUTHEAST. REALLY TOUGH TO GET
WARNING CRITERIA WINDS AT NIGHT INTO THE RRV...AND FELT CHANCES
FOR THAT ARE QUITE LOW. ADVISORY LEVEL WINDS SEEM A MUCH BETTER
BET. FELT TOO THAT PERIOD OF WARNING LEVEL WIND GUSTS IN FAR WRN
FCST AREA IS LIMITED AS WELL TO LATE AFTN-EVE AND THEN MORE
ADVISORY LEVELS AS FULL MIXING NOT REALIZED AS MUCH AS GFS
SOUNDINGS WOULD INDICATE. WOULD LIKE TO SEE A STRONGER PUSH OF
COLD ADVECTION AND PRESSURE RISE COUPLET THAN WHAT I SEE FOR A
LONGER PD OF WARNING CRITERIA WIND SPEEDS. THIS IDEA GENERALLY
FOLLOWS LAV MOS GUIDANCE WELL WITH WIND GUSTS 45-49 KTS IN DVL
00Z-04Z PERIOD....THEN A BIT LOWER MORE LIKE 40-45 KT AFTER THAT.
INTO THE RRV AND GFK/FAR LAV MOS WINDS MORE SO 35-40 KT WIND
GUSTS. THE ADVISORY LEVEL WINDS CONTINUE THRU THURSDAY.
DID NOT EXTEND ADVISORY FARTHER EAST INTO ERN HALF OF FCST
YET BASED ON COORDINATION. BUT SOME COUNTIES FROM THIEF RIVER TO
FERGUS FALLS MAY NEED TO BE ADDED FOR THURSDAY AS THAT IS WHEN THE
STRONGEST WINDS THERE WILL OCCUR.
AS FOR WRAPAROUND PRECIP IN THE FORM OF SNOW. PRETTY CONSISTENT IN
SHOWING ABOUT A 12 HR PD OF SNOW 06Z-18Z THU IN NORTHEASTERN FCST
AREA. WPC SNOWFALL FCST SHOWS FAR NORTHEAST IN 3-4 INCH AREA ISOLD
5 MAYBE FLAG ISLAND/ANGLE INLET AND THAT SEEMS REASONABLE. MOST OF
THIS IS NOT TIL WELL PAST 00Z AND MORE SO 06Z AND AFTER AND THUS
ENOUGH TIME TO MONITOR FURTHER FOR ANY WINTER WX ADVISORY
HEADLINES.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
LINGERING SNOW SHOWERS IN LAKE OF THE WOODS AREA OTHERWISE SKIES
BEGIN TO CLEAR SW HALF OF THE FCST AREA AND SPREAD EAST AS UPPER
LOW DEPARTS SLOWLY THRU NRN ONTARIO THRU FRIDAY NIGHT.
FOR THE SATURDAY THROUGH TUESDAY PERIOD...THE UPPER PATTERN BECOMES
MORE PROGRESSIVE AS THE TROF SHIFTS OVER THE GREAT LAKES. THICKNESS
VALUES INCREASE BY LATE SUNDAY/MONDAY AS A BROAD UPPER RIDGE
RETURNS...AND SOUTHERLY SFC WINDS POINT TOWARD A WARMING TREND FOR
THE END OF THE FORECAST PERIOD. LITTLE PCPN IS ANTICIPATED ATTM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1236 PM CST WED NOV 18 2015
DIFFICULT SET OF TAFS WITH FG/BR AND LOW CIGS AND TIMING
OF WINDS THIS EVENING. COLD FRONT WILL PUSH ACROSS THE AREA WITH
WNW WIND GUSTS THIS EVENING IN THE 40 TO 50 KT RANGE. WINDS WILL BE
STRONG OVERNIGHT WITH 30 TO 40 KT GUSTS. RAIN WILL CHANGE OVER TO
SNOW AT BJI WITH SOME WRAPAROUND SNOW WORKING INTO THE GFK AND TVF
TERMINALS BY MORNING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND ADVISORY FROM 6 PM THIS EVENING TO 8 PM CST THURSDAY FOR
NDZ008-016-027-029-030-039-049-052-053.
HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO MIDNIGHT CST
TONIGHT FOR NDZ006-007-014-015-024-026-028-038-054.
WIND ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST THURSDAY FOR
NDZ006-007-014-015-024-026-028-038-054.
MN...WIND ADVISORY FROM 6 PM THIS EVENING TO 8 PM CST THURSDAY FOR
MNZ001>004-007-029.
&&
$$
UPDATE...VOELKER
SHORT TERM...RIDDLE
LONG TERM...HOPKINS/RIDDLE
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
954 AM CST WED NOV 18 2015
.UPDATE...
ISSUED AT 950 AM CST WED NOV 18 2015
RAIN BAND SETTING UP ACROSS WESTERN MN LINING UP WELL WITH CURRENT
POPS. WEAKENING BAND PUSHING INTO THE FAR NW FA ASSOCIATED WITH
MID LEVEL CLOUDS AND NOT LIKELY REACHING THE GROUND. SURFACE
TEMPERATURES SUBFREEZING HOWEVER GUIDANCE WARMS ROAD SURFACES
ABOVE FREEZING OVER THE NEXT HOUR. CANNOT RULE OUT A BRIEF SPIT
HOWEVER NOT LIKELY TO CAUSE ANY TRAVEL IMPACTS. DID LOWER POPS
SLIGHTLY OVER THE WESTERN AREAS THROUGH NOON. NO OTHER CHANGES.
UPDATE ISSUED AT 707 AM CST WED NOV 18 2015
BAND OF PRECIP IN CNTRL ND ATTM MINOT TO BISMARCK MOVING EAST. CAM
MODELS INSIST IT WILL FALL APART AS IT MOVES EAST...BUT UNSURE SO
WILL MAINTAIN A LOW POP AS IT MOVES EAST. MORE TRACE EVENT STUFF.
ISSUE IS TEMPS AS CLOUDS WILL COME IN WITH THE PRECIP AND WARM UP
ENOUGH TO BE MOSTLY LIQUID BUT ISSUE IS NEXT 1-2 HOURS AS PRECIP
ARRIVES INTO FAR NW FCST AREA AND MAY DO SO IN TIME BEFORE TEMPS
RISE. WILL MENTION FZRA/RA IN FAR NW FCST AREA FOR THIS AT 15Z
THEN JUST -RA 16Z ONWARD. WILL NEED TO WATCH. O/W NO CHANGES.
VARIOUS 06Z MODEL DATA SUPPORTS PREV WIND IDEAS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
MODELS REMAIN PRETTY CONSISTENT OVERALL...BUT DETAILS ON WIND AND
SNOW ARE TOUGH. FIRST OFF...AREA OF RAIN ASSOC WITH MAIN UPPER LOW
IN KANSAS LIFTING NORTHEAST IS A BIT FARTHER EAST THAN EARLIER
PROGGED. THUS DID PUSH THE HIGH POPS A BIT EAST AND EAST OF THE
RRV. CLOUD-CLEAR LINE FROM LAST EVENING HOLDING AS EXPECTED
HALLOCK-GRAND FORKS-FORMAN ND. SOME FOG NOTICED ESP EAST OF THE
RRV ON THE WRN FLANK OF THE LOW CLOUDS WITH SEVERAL SITES FROM
ROSEAU TO FOSSTON TO DTL DOWN 1/2 MILE OR LESS. ADDED AREAS OF FOG
THIS AREA THRU THE MORNING.
FOR THE DAY...THE RAIN WILL SPREAD UP THRU THE ERN FCST
AREA...WHILE CLOUDS INCREASE FROM THE WEST. CLEAR AREA OVER WRN
FCST AREA WHERE TEMPS DROPPED INTO THE LOW 20S WILL WARM UP AS
THERE IS A PERIOD OF SOUTHWEST WIND AHD OF THE FRONT AND COOLER
AIR. HRRR INDICATES A BAND OF LIGHT PRECIP ALONG THE COLD FRONT
ENTERING DVL REGION EARLY AFTN AND INTO RRV LATE AFTN. RE-WORKED
SOME POPS FOR THIS. MORE GLOBAL MODELS WEAKEN THIS. RADAR OUT WEST
SHOWS PCPN VERY LIGHT AND SCATTERED AND THUS HAVE ONLY LOW POPS
FOR ANY AFTN PRECIP IN ERN ND.
ISSUE IS WIND. IT DOES APPEAR THAT JUST BEHIND THE FRONT FOR A FEW
HOURS THERE IS ENOUGH PRESSURE RISE, 850 MB COLD ADVECTION AND
STEEP LOW LEVEL LAPSE RATE TO BRING SOME OF THE 850 MB WINDS
(55-60 KT) TO THE SFC IN CNTRL ND AND WRN FCST AREA VERY LATE
AFTN-EVE. AS THESE HIGHER WINDS ALOFT MOVE INTO THE RED RIVER
VALLEY TONIGHT FEEL FULL MIXING WILL NOT BE REALIZED AS MAIN CORE
OF PRESSURE RISES CONTINUES TO DROP SOUTHEAST. REALLY TOUGH TO GET
WARNING CRITERIA WINDS AT NIGHT INTO THE RRV...AND FELT CHANCES
FOR THAT ARE QUITE LOW. ADVISORY LEVEL WINDS SEEM A MUCH BETTER
BET. FELT TOO THAT PERIOD OF WARNING LEVEL WIND GUSTS IN FAR WRN
FCST AREA IS LIMITED AS WELL TO LATE AFTN-EVE AND THEN MORE
ADVISORY LEVELS AS FULL MIXING NOT REALIZED AS MUCH AS GFS
SOUNDINGS WOULD INDICATE. WOULD LIKE TO SEE A STRONGER PUSH OF
COLD ADVECTION AND PRESSURE RISE COUPLET THAN WHAT I SEE FOR A
LONGER PD OF WARNING CRITERIA WIND SPEEDS. THIS IDEA GENERALLY
FOLLOWS LAV MOS GUIDANCE WELL WITH WIND GUSTS 45-49 KTS IN DVL
00Z-04Z PERIOD....THEN A BIT LOWER MORE LIKE 40-45 KT AFTER THAT.
INTO THE RRV AND GFK/FAR LAV MOS WINDS MORE SO 35-40 KT WIND
GUSTS. THE ADVISORY LEVEL WINDS CONTINUE THRU THURSDAY.
DID NOT EXTEND ADVISORY FARTHER EAST INTO ERN HALF OF FCST
YET BASED ON COORDINATION. BUT SOME COUNTIES FROM THIEF RIVER TO
FERGUS FALLS MAY NEED TO BE ADDED FOR THURSDAY AS THAT IS WHEN THE
STRONGEST WINDS THERE WILL OCCUR.
AS FOR WRAPAROUND PRECIP IN THE FORM OF SNOW. PRETTY CONSISTENT IN
SHOWING ABOUT A 12 HR PD OF SNOW 06Z-18Z THU IN NORTHEASTERN FCST
AREA. WPC SNOWFALL FCST SHOWS FAR NORTHEAST IN 3-4 INCH AREA ISOLD
5 MAYBE FLAG ISLAND/ANGLE INLET AND THAT SEEMS REASONABLE. MOST OF
THIS IS NOT TIL WELL PAST 00Z AND MORE SO 06Z AND AFTER AND THUS
ENOUGH TIME TO MONITOR FURTHER FOR ANY WINTER WX ADVISORY
HEADLINES.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
LINGERING SNOW SHOWERS IN LAKE OF THE WOODS AREA OTHERWISE SKIES
BEGIN TO CLEAR SW HALF OF THE FCST AREA AND SPREAD EAST AS UPPER
LOW DEPARTS SLOWLY THRU NRN ONTARIO THRU FRIDAY NIGHT.
FOR THE SATURDAY THROUGH TUESDAY PERIOD...THE UPPER PATTERN BECOMES
MORE PROGRESSIVE AS THE TROF SHIFTS OVER THE GREAT LAKES. THICKNESS
VALUES INCREASE BY LATE SUNDAY/MONDAY AS A BROAD UPPER RIDGE
RETURNS...AND SOUTHERLY SFC WINDS POINT TOWARD A WARMING TREND FOR
THE END OF THE FORECAST PERIOD. LITTLE PCPN IS ANTICIPATED ATTM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 707 AM CST WED NOV 18 2015
MESSY TAFS AS WIDESPREAD IFR CIGS HCO-GFK-FAR EASTWARD. WIDESPREAD
RAIN IN MINNESOTA THRU THE DAY AND CONTINUED IFR CIGS EXPECTED.
PATCHY FOG NR FARGO WILL LIFT THIS MORNING. MAIN ISSUE WILL BE THE
ARRIVAL FOR STRONG WINDS LATER TODAY AND TONIGHT. WIND GUST TO 50
KTS KDVL PSBL 22Z-03Z PERIOD... AND 35-40 KTS INTO GFK-FAR 02-06Z
PERIOD PSBL 45 KT. DIRECTION FROM WEST-NORTHWEST.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND ADVISORY FROM 6 PM THIS EVENING TO 8 PM CST THURSDAY FOR
NDZ008-016-027-029-030-039-049-052-053.
HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO MIDNIGHT CST
TONIGHT FOR NDZ006-007-014-015-024-026-028-038-054.
WIND ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST THURSDAY FOR
NDZ006-007-014-015-024-026-028-038-054.
MN...WIND ADVISORY FROM 6 PM THIS EVENING TO 8 PM CST THURSDAY FOR
MNZ001>004-007-029.
&&
$$
UPDATE...VOELKER
SHORT TERM...RIDDLE
LONG TERM...HOPKINS/RIDDLE
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
711 AM CST WED NOV 18 2015
.UPDATE...
ISSUED AT 707 AM CST WED NOV 18 2015
BAND OF PRECIP IN CNTRL ND ATTM MINOT TO BISMARCK MOVING EAST. CAM
MODELS INSIST IT WILL FALL APART AS IT MOVES EAST...BUT UNSURE SO
WILL MAINTAIN A LOW POP AS IT MOVES EAST. MORE TRACE EVENT STUFF.
ISSUE IS TEMPS AS CLOUDS WILL COME IN WITH THE PRECIP AND WARM UP
ENOUGH TO BE MOSTLY LIQUID BUT ISSUE IS NEXT 1-2 HOURS AS PRECIP
ARRIVES INTO FAR NW FCST AREA AND MAY DO SO IN TIME BEFORE TEMPS
RISE. WILL MENTION FZRA/RA IN FAR NW FCST AREA FOR THIS AT 15Z
THEN JUST -RA 16Z ONWARD. WILL NEED TO WATCH. O/W NO CHANGES.
VARIOUS 06Z MODEL DATA SUPPORTS PREV WIND IDEAS.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
MODELS REMAIN PRETTY CONSISTENT OVERALL...BUT DETAILS ON WIND AND
SNOW ARE TOUGH. FIRST OFF...AREA OF RAIN ASSOC WITH MAIN UPPER LOW
IN KANSAS LIFTING NORTHEAST IS A BIT FARTHER EAST THAN EARLIER
PROGGED. THUS DID PUSH THE HIGH POPS A BIT EAST AND EAST OF THE
RRV. CLOUD-CLEAR LINE FROM LAST EVENING HOLDING AS EXPECTED
HALLOCK-GRAND FORKS-FORMAN ND. SOME FOG NOTICED ESP EAST OF THE
RRV ON THE WRN FLANK OF THE LOW CLOUDS WITH SEVERAL SITES FROM
ROSEAU TO FOSSTON TO DTL DOWN 1/2 MILE OR LESS. ADDED AREAS OF FOG
THIS AREA THRU THE MORNING.
FOR THE DAY...THE RAIN WILL SPREAD UP THRU THE ERN FCST
AREA...WHILE CLOUDS INCREASE FROM THE WEST. CLEAR AREA OVER WRN
FCST AREA WHERE TEMPS DROPPED INTO THE LOW 20S WILL WARM UP AS
THERE IS A PERIOD OF SOUTHWEST WIND AHD OF THE FRONT AND COOLER
AIR. HRRR INDICATES A BAND OF LIGHT PRECIP ALONG THE COLD FRONT
ENTERING DVL REGION EARLY AFTN AND INTO RRV LATE AFTN. RE-WORKED
SOME POPS FOR THIS. MORE GLOBAL MODELS WEAKEN THIS. RADAR OUT WEST
SHOWS PCPN VERY LIGHT AND SCATTERED AND THUS HAVE ONLY LOW POPS
FOR ANY AFTN PRECIP IN ERN ND.
ISSUE IS WIND. IT DOES APPEAR THAT JUST BEHIND THE FRONT FOR A FEW
HOURS THERE IS ENOUGH PRESSURE RISE, 850 MB COLD ADVECTION AND
STEEP LOW LEVEL LAPSE RATE TO BRING SOME OF THE 850 MB WINDS
(55-60 KT) TO THE SFC IN CNTRL ND AND WRN FCST AREA VERY LATE
AFTN-EVE. AS THESE HIGHER WINDS ALOFT MOVE INTO THE RED RIVER
VALLEY TONIGHT FEEL FULL MIXING WILL NOT BE REALIZED AS MAIN CORE
OF PRESSURE RISES CONTINUES TO DROP SOUTHEAST. REALLY TOUGH TO GET
WARNING CRITERIA WINDS AT NIGHT INTO THE RRV...AND FELT CHANCES
FOR THAT ARE QUITE LOW. ADVISORY LEVEL WINDS SEEM A MUCH BETTER
BET. FELT TOO THAT PERIOD OF WARNING LEVEL WIND GUSTS IN FAR WRN
FCST AREA IS LIMITED AS WELL TO LATE AFTN-EVE AND THEN MORE
ADVISORY LEVELS AS FULL MIXING NOT REALIZED AS MUCH AS GFS
SOUNDINGS WOULD INDICATE. WOULD LIKE TO SEE A STRONGER PUSH OF
COLD ADVECTION AND PRESSURE RISE COUPLET THAN WHAT I SEE FOR A
LONGER PD OF WARNING CRITERIA WIND SPEEDS. THIS IDEA GENERALLY
FOLLOWS LAV MOS GUIDANCE WELL WITH WIND GUSTS 45-49 KTS IN DVL
00Z-04Z PERIOD....THEN A BIT LOWER MORE LIKE 40-45 KT AFTER THAT.
INTO THE RRV AND GFK/FAR LAV MOS WINDS MORE SO 35-40 KT WIND
GUSTS. THE ADVISORY LEVEL WINDS CONTINUE THRU THURSDAY.
DID NOT EXTEND ADVISORY FARTHER EAST INTO ERN HALF OF FCST
YET BASED ON COORDINATION. BUT SOME COUNTIES FROM THIEF RIVER TO
FERGUS FALLS MAY NEED TO BE ADDED FOR THURSDAY AS THAT IS WHEN THE
STRONGEST WINDS THERE WILL OCCUR.
AS FOR WRAPAROUND PRECIP IN THE FORM OF SNOW. PRETTY CONSISTENT IN
SHOWING ABOUT A 12 HR PD OF SNOW 06Z-18Z THU IN NORTHEASTERN FCST
AREA. WPC SNOWFALL FCST SHOWS FAR NORTHEAST IN 3-4 INCH AREA ISOLD
5 MAYBE FLAG ISLAND/ANGLE INLET AND THAT SEEMS REASONABLE. MOST OF
THIS IS NOT TIL WELL PAST 00Z AND MORE SO 06Z AND AFTER AND THUS
ENOUGH TIME TO MONITOR FURTHER FOR ANY WINTER WX ADVISORY
HEADLINES.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
LINGERING SNOW SHOWERS IN LAKE OF THE WOODS AREA OTHERWISE SKIES
BEGIN TO CLEAR SW HALF OF THE FCST AREA AND SPREAD EAST AS UPPER
LOW DEPARTS SLOWLY THRU NRN ONTARIO THRU FRIDAY NIGHT.
FOR THE SATURDAY THROUGH TUESDAY PERIOD...THE UPPER PATTERN BECOMES
MORE PROGRESSIVE AS THE TROF SHIFTS OVER THE GREAT LAKES. THICKNESS
VALUES INCREASE BY LATE SUNDAY/MONDAY AS A BROAD UPPER RIDGE
RETURNS...AND SOUTHERLY SFC WINDS POINT TOWARD A WARMING TREND FOR
THE END OF THE FORECAST PERIOD. LITTLE PCPN IS ANTICIPATED ATTM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 707 AM CST WED NOV 18 2015
MESSY TAFS AS WIDESPREAD IFR CIGS HCO-GFK-FAR EASTWARD. WIDESPREAD
RAIN IN MINNESOTA THRU THE DAY AND CONTINUED IFR CIGS EXPECTED.
PATCHY FOG NR FARGO WILL LIFT THIS MORNING. MAIN ISSUE WILL BE THE
ARRIVAL FOR STRONG WINDS LATER TODAY AND TONIGHT. WIND GUST TO 50
KTS KDVL PSBL 22Z-03Z PERIOD... AND 35-40 KTS INTO GFK-FAR 02-06Z
PERIOD PSBL 45 KT. DIRECTION FROM WEST-NORTHWEST.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND ADVISORY FROM 6 PM THIS EVENING TO 8 PM CST THURSDAY FOR
NDZ008-016-027-029-030-039-049-052-053.
HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO MIDNIGHT CST
TONIGHT FOR NDZ006-007-014-015-024-026-028-038-054.
WIND ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST THURSDAY FOR
NDZ006-007-014-015-024-026-028-038-054.
MN...WIND ADVISORY FROM 6 PM THIS EVENING TO 8 PM CST THURSDAY FOR
MNZ001>004-007-029.
&&
$$
UPDATE...RIDDLE
SHORT TERM...RIDDLE
LONG TERM...HOPKINS/RIDDLE
AVIATION...RIDDLE
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
348 AM CST WED NOV 18 2015
CORRECTED ONCE MORE FOR WIND HEADLINE TIMING.
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
MODELS REMAIN PRETTY CONSISTENT OVERALL...BUT DETAILS ON WIND AND
SNOW ARE TOUGH. FIRST OFF...AREA OF RAIN ASSOC WITH MAIN UPPER LOW
IN KANSAS LIFTING NORTHEAST IS A BIT FARTHER EAST THAN EARLIER
PROGGED. THUS DID PUSH THE HIGH POPS A BIT EAST AND EAST OF THE
RRV. CLOUD-CLEAR LINE FROM LAST EVENING HOLDING AS EXPECTED
HALLOCK-GRAND FORKS-FORMAN ND. SOME FOG NOTICED ESP EAST OF THE
RRV ON THE WRN FLANK OF THE LOW CLOUDS WITH SEVERAL SITES FROM
ROSEAU TO FOSSTON TO DTL DOWN 1/2 MILE OR LESS. ADDED AREAS OF FOG
THIS AREA THRU THE MORNING.
FOR THE DAY...THE RAIN WILL SPREAD UP THRU THE ERN FCST
AREA...WHILE CLOUDS INCREASE FROM THE WEST. CLEAR AREA OVER WRN
FCST AREA WHERE TEMPS DROPPED INTO THE LOW 20S WILL WARM UP AS
THERE IS A PERIOD OF SOUTHWEST WIND AHD OF THE FRONT AND COOLER
AIR. HRRR INDICATES A BAND OF LIGHT PRECIP ALONG THE COLD FRONT
ENTERING DVL REGION EARLY AFTN AND INTO RRV LATE AFTN. RE-WORKED
SOME POPS FOR THIS. MORE GLOBAL MODELS WEAKEN THIS. RADAR OUT WEST
SHOWS PCPN VERY LIGHT AND SCATTERED AND THUS HAVE ONLY LOW POPS
FOR ANY AFTN PRECIP IN ERN ND.
ISSUE IS WIND. IT DOES APPEAR THAT JUST BEHIND THE FRONT FOR A FEW
HOURS THERE IS ENOUGH PRESSURE RISE, 850 MB COLD ADVECTION AND
STEEP LOW LEVEL LAPSE RATE TO BRING SOME OF THE 850 MB WINDS
(55-60 KT) TO THE SFC IN CNTRL ND AND WRN FCST AREA VERY LATE
AFTN-EVE. AS THESE HIGHER WINDS ALOFT MOVE INTO THE RED RIVER
VALLEY TONIGHT FEEL FULL MIXING WILL NOT BE REALIZED AS MAIN CORE
OF PRESSURE RISES CONTINUES TO DROP SOUTHEAST. REALLY TOUGH TO GET
WARNING CRITERIA WINDS AT NIGHT INTO THE RRV...AND FELT CHANCES
FOR THAT ARE QUITE LOW. ADVISORY LEVEL WINDS SEEM A MUCH BETTER
BET. FELT TOO THAT PERIOD OF WARNING LEVEL WIND GUSTS IN FAR WRN
FCST AREA IS LIMITED AS WELL TO LATE AFTN-EVE AND THEN MORE
ADVISORY LEVELS AS FULL MIXING NOT REALIZED AS MUCH AS GFS
SOUNDINGS WOULD INDICATE. WOULD LIKE TO SEE A STRONGER PUSH OF
COLD ADVECTION AND PRESSURE RISE COUPLET THAN WHAT I SEE FOR A
LONGER PD OF WARNING CRITERIA WIND SPEEDS. THIS IDEA GENERALLY
FOLLOWS LAV MOS GUIDANCE WELL WITH WIND GUSTS 45-49 KTS IN DVL
00Z-04Z PERIOD....THEN A BIT LOWER MORE LIKE 40-45 KT AFTER THAT.
INTO THE RRV AND GFK/FAR LAV MOS WINDS MORE SO 35-40 KT WIND
GUSTS. THE ADVISORY LEVEL WINDS CONTINUE THRU THURSDAY.
DID NOT EXTEND ADVISORY FARTHER EAST INTO ERN HALF OF FCST
YET BASED ON COORDINATION. BUT SOME COUNTIES FROM THIEF RIVER TO
FERGUS FALLS MAY NEED TO BE ADDED FOR THURSDAY AS THAT IS WHEN THE
STRONGEST WINDS THERE WILL OCCUR.
AS FOR WRAPAROUND PRECIP IN THE FORM OF SNOW. PRETTY CONSISTENT IN
SHOWING ABOUT A 12 HR PD OF SNOW 06Z-18Z THU IN NORTHEASTERN FCST
AREA. WPC SNOWFALL FCST SHOWS FAR NORTHEAST IN 3-4 INCH AREA ISOLD
5 MAYBE FLAG ISLAND/ANGLE INLET AND THAT SEEMS REASONABLE. MOST OF
THIS IS NOT TIL WELL PAST 00Z AND MORE SO 06Z AND AFTER AND THUS
ENOUGH TIME TO MONITOR FURTHER FOR ANY WINTER WX ADVISORY
HEADLINES.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
LINGERING SNOW SHOWERS IN LAKE OF THE WOODS AREA OTHERWISE SKIES
BEGIN TO CLEAR SW HALF OF THE FCST AREA AND SPREAD EAST AS UPPER
LOW DEPARTS SLOWLY THRU NRN ONTARIO THRU FRIDAY NIGHT.
FOR THE SATURDAY THROUGH TUESDAY PERIOD...THE UPPER PATTERN BECOMES
MORE PROGRESSIVE AS THE TROF SHIFTS OVER THE GREAT LAKES. THICKNESS
VALUES INCREASE BY LATE SUNDAY/MONDAY AS A BROAD UPPER RIDGE
RETURNS...AND SOUTHERLY SFC WINDS POINT TOWARD A WARMING TREND FOR
THE END OF THE FORECAST PERIOD. LITTLE PCPN IS ANTICIPATED ATTM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1125 PM CST TUE NOV 17 2015
IFR CONDITIONS WILL PERSIST IN THE EAST AS THE CLEARING LINE
REMAINS NEARLY STATIONARY. NW WINDS WILL INCREASE AND GUST OVER
40KT BY LATE WED AFTERNOON NEAR KDVL...SPREADING EAST INTO THE
VALLEY WED EVENING. CONDITIONS SHOULD IMPROVE INTO THE MVFR RANGE
IN THE EAST WED EVENING AS A COLD FRONT SWEEPS QUICKLY THROUGH THE
REGION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND ADVISORY FROM 6 PM THIS EVENING TO 8 PM CST THURSDAY FOR
NDZ008-016-027-029-030-039-049-052-053.
HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO MIDNIGHT CST
TONIGHT FOR NDZ006-007-014-015-024-026-028-038-054.
WIND ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST THURSDAY FOR
NDZ006-007-014-015-024-026-028-038-054.
MN...WIND ADVISORY FROM 6 PM THIS EVENING TO 8 PM CST THURSDAY FOR
MNZ001>004-007-029.
&&
$$
SHORT TERM...RIDDLE
LONG TERM...HOPKINS/RIDDLE
AVIATION...DK
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
342 AM CST WED NOV 18 2015
CORRECTION ISSUED FOR TIMING OF HIGH WIND WARNING AND ADVISORY
CODING AT BOTTOM
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
MODELS REMAIN PRETTY CONSISTENT OVERALL...BUT DETAILS ON WIND AND
SNOW ARE TOUGH. FIRST OFF...AREA OF RAIN ASSOC WITH MAIN UPPER LOW
IN KANSAS LIFTING NORTHEAST IS A BIT FARTHER EAST THAN EARLIER
PROGGED. THUS DID PUSH THE HIGH POPS A BIT EAST AND EAST OF THE
RRV. CLOUD-CLEAR LINE FROM LAST EVENING HOLDING AS EXPECTED
HALLOCK-GRAND FORKS-FORMAN ND. SOME FOG NOTICED ESP EAST OF THE
RRV ON THE WRN FLANK OF THE LOW CLOUDS WITH SEVERAL SITES FROM
ROSEAU TO FOSSTON TO DTL DOWN 1/2 MILE OR LESS. ADDED AREAS OF FOG
THIS AREA THRU THE MORNING.
FOR THE DAY...THE RAIN WILL SPREAD UP THRU THE ERN FCST
AREA...WHILE CLOUDS INCREASE FROM THE WEST. CLEAR AREA OVER WRN
FCST AREA WHERE TEMPS DROPPED INTO THE LOW 20S WILL WARM UP AS
THERE IS A PERIOD OF SOUTHWEST WIND AHD OF THE FRONT AND COOLER
AIR. HRRR INDICATES A BAND OF LIGHT PRECIP ALONG THE COLD FRONT
ENTERING DVL REGION EARLY AFTN AND INTO RRV LATE AFTN. RE-WORKED
SOME POPS FOR THIS. MORE GLOBAL MODELS WEAKEN THIS. RADAR OUT WEST
SHOWS PCPN VERY LIGHT AND SCATTERED AND THUS HAVE ONLY LOW POPS
FOR ANY AFTN PRECIP IN ERN ND.
ISSUE IS WIND. IT DOES APPEAR THAT JUST BEHIND THE FRONT FOR A FEW
HOURS THERE IS ENOUGH PRESSURE RISE, 850 MB COLD ADVECTION AND
STEEP LOW LEVEL LAPSE RATE TO BRING SOME OF THE 850 MB WINDS
(55-60 KT) TO THE SFC IN CNTRL ND AND WRN FCST AREA VERY LATE
AFTN-EVE. AS THESE HIGHER WINDS ALOFT MOVE INTO THE RED RIVER
VALLEY TONIGHT FEEL FULL MIXING WILL NOT BE REALIZED AS MAIN CORE
OF PRESSURE RISES CONTINUES TO DROP SOUTHEAST. REALLY TOUGH TO GET
WARNING CRITERIA WINDS AT NIGHT INTO THE RRV...AND FELT CHANCES
FOR THAT ARE QUITE LOW. ADVISORY LEVEL WINDS SEEM A MUCH BETTER
BET. FELT TOO THAT PERIOD OF WARNING LEVEL WIND GUSTS IN FAR WRN
FCST AREA IS LIMITED AS WELL TO LATE AFTN-EVE AND THEN MORE
ADVISORY LEVELS AS FULL MIXING NOT REALIZED AS MUCH AS GFS
SOUNDINGS WOULD INDICATE. WOULD LIKE TO SEE A STRONGER PUSH OF
COLD ADVECTION AND PRESSURE RISE COUPLET THAN WHAT I SEE FOR A
LONGER PD OF WARNING CRITERIA WIND SPEEDS. THIS IDEA GENERALLY
FOLLOWS LAV MOS GUIDANCE WELL WITH WIND GUSTS 45-49 KTS IN DVL
00Z-04Z PERIOD....THEN A BIT LOWER MORE LIKE 40-45 KT AFTER THAT.
INTO THE RRV AND GFK/FAR LAV MOS WINDS MORE SO 35-40 KT WIND
GUSTS. THE ADVISORY LEVEL WINDS CONTINUE THRU THURSDAY.
DID NOT EXTEND ADVISORY FARTHER EAST INTO ERN HALF OF FCST
YET BASED ON COORDINATION. BUT SOME COUNTIES FROM THIEF RIVER TO
FERGUS FALLS MAY NEED TO BE ADDED FOR THURSDAY AS THAT IS WHEN THE
STRONGEST WINDS THERE WILL OCCUR.
AS FOR WRAPAROUND PRECIP IN THE FORM OF SNOW. PRETTY CONSISTENT IN
SHOWING ABOUT A 12 HR PD OF SNOW 06Z-18Z THU IN NORTHEASTERN FCST
AREA. WPC SNOWFALL FCST SHOWS FAR NORTHEAST IN 3-4 INCH AREA ISOLD
5 MAYBE FLAG ISLAND/ANGLE INLET AND THAT SEEMS REASONABLE. MOST OF
THIS IS NOT TIL WELL PAST 00Z AND MORE SO 06Z AND AFTER AND THUS
ENOUGH TIME TO MONITOR FURTHER FOR ANY WINTER WX ADVISORY
HEADLINES.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
LINGERING SNOW SHOWERS IN LAKE OF THE WOODS AREA OTHERWISE SKIES
BEGIN TO CLEAR SW HALF OF THE FCST AREA AND SPREAD EAST AS UPPER
LOW DEPARTS SLOWLY THRU NRN ONTARIO THRU FRIDAY NIGHT.
FOR THE SATURDAY THROUGH TUESDAY PERIOD...THE UPPER PATTERN BECOMES
MORE PROGRESSIVE AS THE TROF SHIFTS OVER THE GREAT LAKES. THICKNESS
VALUES INCREASE BY LATE SUNDAY/MONDAY AS A BROAD UPPER RIDGE
RETURNS...AND SOUTHERLY SFC WINDS POINT TOWARD A WARMING TREND FOR
THE END OF THE FORECAST PERIOD. LITTLE PCPN IS ANTICIPATED ATTM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1125 PM CST TUE NOV 17 2015
IFR CONDITIONS WILL PERSIST IN THE EAST AS THE CLEARING LINE
REMAINS NEARLY STATIONARY. NW WINDS WILL INCREASE AND GUST OVER
40KT BY LATE WED AFTERNOON NEAR KDVL...SPREADING EAST INTO THE
VALLEY WED EVENING. CONDITIONS SHOULD IMPROVE INTO THE MVFR RANGE
IN THE EAST WED EVENING AS A COLD FRONT SWEEPS QUICKLY THROUGH THE
REGION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST THURSDAY FOR
NDZ006>008-014>016-024-026>030-038-039-049-052>054.
HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO MIDNIGHT CST
TONIGHT FOR NDZ006-007-014-015-024-026-028-038-054.
MN...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST THURSDAY FOR
MNZ001>004-007-029.
&&
$$
SHORT TERM...RIDDLE
LONG TERM...HOPKINS/RIDDLE
AVIATION...DK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
337 AM CST WED NOV 18 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
MODELS REMAIN PRETTY CONSISTENT OVERALL...BUT DETAILS ON WIND AND
SNOW ARE TOUGH. FIRST OFF...AREA OF RAIN ASSOC WITH MAIN UPPER LOW
IN KANSAS LIFTING NORTHEAST IS A BIT FARTHER EAST THAN EARLIER
PROGGED. THUS DID PUSH THE HIGH POPS A BIT EAST AND EAST OF THE
RRV. CLOUD-CLEAR LINE FROM LAST EVENING HOLDING AS EXPECTED
HALLOCK-GRAND FORKS-FORMAN ND. SOME FOG NOTICED ESP EAST OF THE
RRV ON THE WRN FLANK OF THE LOW CLOUDS WITH SEVERAL SITES FROM
ROSEAU TO FOSSTON TO DTL DOWN 1/2 MILE OR LESS. ADDED AREAS OF FOG
THIS AREA THRU THE MORNING.
FOR THE DAY...THE RAIN WILL SPREAD UP THRU THE ERN FCST
AREA...WHILE CLOUDS INCREASE FROM THE WEST. CLEAR AREA OVER WRN
FCST AREA WHERE TEMPS DROPPED INTO THE LOW 20S WILL WARM UP AS
THERE IS A PERIOD OF SOUTHWEST WIND AHD OF THE FRONT AND COOLER
AIR. HRRR INDICATES A BAND OF LIGHT PRECIP ALONG THE COLD FRONT
ENTERING DVL REGION EARLY AFTN AND INTO RRV LATE AFTN. RE-WORKED
SOME POPS FOR THIS. MORE GLOBAL MODELS WEAKEN THIS. RADAR OUT WEST
SHOWS PCPN VERY LIGHT AND SCATTERED AND THUS HAVE ONLY LOW POPS
FOR ANY AFTN PRECIP IN ERN ND.
ISSUE IS WIND. IT DOES APPEAR THAT JUST BEHIND THE FRONT FOR A FEW
HOURS THERE IS ENOUGH PRESSURE RISE, 850 MB COLD ADVECTION AND
STEEP LOW LEVEL LAPSE RATE TO BRING SOME OF THE 850 MB WINDS
(55-60 KT) TO THE SFC IN CNTRL ND AND WRN FCST AREA VERY LATE
AFTN-EVE. AS THESE HIGHER WINDS ALOFT MOVE INTO THE RED RIVER
VALLEY TONIGHT FEEL FULL MIXING WILL NOT BE REALIZED AS MAIN CORE
OF PRESSURE RISES CONTINUES TO DROP SOUTHEAST. REALLY TOUGH TO GET
WARNING CRITERIA WINDS AT NIGHT INTO THE RRV...AND FELT CHANCES
FOR THAT ARE QUITE LOW. ADVISORY LEVEL WINDS SEEM A MUCH BETTER
BET. FELT TOO THAT PERIOD OF WARNING LEVEL WIND GUSTS IN FAR WRN
FCST AREA IS LIMITED AS WELL TO LATE AFTN-EVE AND THEN MORE
ADVISORY LEVELS AS FULL MIXING NOT REALIZED AS MUCH AS GFS
SOUNDINGS WOULD INDICATE. WOULD LIKE TO SEE A STRONGER PUSH OF
COLD ADVECTION AND PRESSURE RISE COUPLET THAN WHAT I SEE FOR A
LONGER PD OF WARNING CRITERIA WIND SPEEDS. THIS IDEA GENERALLY
FOLLOWS LAV MOS GUIDANCE WELL WITH WIND GUSTS 45-49 KTS IN DVL
00Z-04Z PERIOD....THEN A BIT LOWER MORE LIKE 40-45 KT AFTER THAT.
INTO THE RRV AND GFK/FAR LAV MOS WINDS MORE SO 35-40 KT WIND
GUSTS. THE ADVISORY LEVEL WINDS CONTINUE THRU THURSDAY.
DID NOT EXTEND ADVISORY FARTHER EAST INTO ERN HALF OF FCST
YET BASED ON COORDINATION. BUT SOME COUNTIES FROM THIEF RIVER TO
FERGUS FALLS MAY NEED TO BE ADDED FOR THURSDAY AS THAT IS WHEN THE
STRONGEST WINDS THERE WILL OCCUR.
AS FOR WRAPAROUND PRECIP IN THE FORM OF SNOW. PRETTY CONSISTENT IN
SHOWING ABOUT A 12 HR PD OF SNOW 06Z-18Z THU IN NORTHEASTERN FCST
AREA. WPC SNOWFALL FCST SHOWS FAR NORTHEAST IN 3-4 INCH AREA ISOLD
5 MAYBE FLAG ISLAND/ANGLE INLET AND THAT SEEMS REASONABLE. MOST OF
THIS IS NOT TIL WELL PAST 00Z AND MORE SO 06Z AND AFTER AND THUS
ENOUGH TIME TO MONITOR FURTHER FOR ANY WINTER WX ADVISORY
HEADLINES.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 324 AM CST WED NOV 18 2015
LINGERING SNOW SHOWERS IN LAKE OF THE WOODS AREA OTHERWISE SKIES
BEGIN TO CLEAR SW HALF OF THE FCST AREA AND SPREAD EAST AS UPPER
LOW DEPARTS SLOWLY THRU NRN ONTARIO THRU FRIDAY NIGHT.
FOR THE SATURDAY THROUGH TUESDAY PERIOD...THE UPPER PATTERN BECOMES
MORE PROGRESSIVE AS THE TROF SHIFTS OVER THE GREAT LAKES. THICKNESS
VALUES INCREASE BY LATE SUNDAY/MONDAY AS A BROAD UPPER RIDGE
RETURNS...AND SOUTHERLY SFC WINDS POINT TOWARD A WARMING TREND FOR
THE END OF THE FORECAST PERIOD. LITTLE PCPN IS ANTICIPATED ATTM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1125 PM CST TUE NOV 17 2015
IFR CONDITIONS WILL PERSIST IN THE EAST AS THE CLEARING LINE
REMAINS NEARLY STATIONARY. NW WINDS WILL INCREASE AND GUST OVER
40KT BY LATE WED AFTERNOON NEAR KDVL...SPREADING EAST INTO THE
VALLEY WED EVENING. CONDITIONS SHOULD IMPROVE INTO THE MVFR RANGE
IN THE EAST WED EVENING AS A COLD FRONT SWEEPS QUICKLY THROUGH THE
REGION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND ADVISORY FROM 11 PM THIS EVENING TO 6 PM CST THURSDAY FOR
NDZ006>008-014>016-024-026>030-038-039-049-052>054.
HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO 11 PM CST THIS
EVENING FOR NDZ006-007-014-015-024-026-028-038-054.
MN...WIND ADVISORY FROM 11 PM THIS EVENING TO 6 PM CST THURSDAY FOR
MNZ001>004-007-029.
&&
$$
SHORT TERM...RIDDLE
LONG TERM...HOPKINS/RIDDLE
AVIATION...DK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
358 PM EST WED NOV 18 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION OVERNIGHT. HIGH PRESSURE
WILL BUILD ACROSS THE CENTRAL MISSISSIPPI VALLEY TO THE LOWER
OHIO VALLEY THURSDAY NIGHT AND FRIDAY. LOW PRESSURE WILL DEVELOP
OVER THE CENTRAL PLAINS FRIDAY AND TRACK TOWARD THE REGION ON
SATURDAY. MUCH COLDER AIR WILL SWEEP INTO THE REGION IN ITS WAKE
ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
MAIN FORECAST ISSUE WILL BE TRACKING THE RAIN BAND CURRENTLY
ENTERING THE WESTERN EDGE OF THE FORECAST AREA ACROSS THE REGION
OVERNIGHT. THE BAND INTENSITY HAS HELD FAIRLY STEADY TODAY AS IT
PROGRESSED SLOWLY EAST. ENHANCED CLOUD TOPS HAVE REMAINED FAIR
CONSTANT WHICH IS CONSISTENT WITH THE RADAR MOSAIC. A THIN LINE OF
MORE INTENSE RADAR ECHOES OVER INDIANA ON THE BACK EDGE OF THE
RAIN CONTINUES TO LIFT MAINLY NORTH WITH SLIGHT WEAKENING ALONG
THE OCCLUDED FRONT. EXPECT A CONTINUED PROGRESSION TO THE EAST
THIS EVENING OF THE RAIN BAND AND HAVE USED THE HRRR WITH MINOR
ADJUSTMENTS. SURFACE WINDS HAVE SUBSIDED SO WILL CANCEL THE WIND
ADVISORY AND DOWNGRADE THE HIGH WIND WARNING NEAR ERI TO A WIND
ADVISORY FOR THIS EVENING.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
THE MODELS ARE IN FAIR AGREEMENT FOR THE PERIOD WITH A COOLING
TREND AND THEN THE CHANCE FOR WINTRY PRECIPITATION OVER THE
WEEKEND. THERE COULD BE A LINGERING SHOWER VERY EARLY THURSDAY
MORNING IN NORTHWEST PA OTHERWISE FAIR WEATHER WILL CONTINUE INTO
FRIDAY EVENING AS COOLER MORE SEASONABLE AIR OVERSPREADS THE
REGION.
LOW PRESSURE WILL APPROACH THE REGION FRIDAY NIGHT AND TRACK
ACROSS LAKE ERIE ON SATURDAY EVENING. THE GFS IS SLIGHTLY FASTER
THAN THE ECMWF WITH NEARLY THE SAME TRACK. THE GFS IS COOLER WITH
SOME POTENTIAL FOR MIXED PRECIPITATION OR PERHAPS JUST WET SNOW
OVER NORTHWEST OHIO GIVEN ITS LOW THICKNESS BELOW 1300M AND 850
MB TEMPERATURES AT OR BELOW -5C. THE ECMWF IS WARMER SO EXPECT
SOME MORNING SNOW OR MIX WHICH COULD CHANGE TO ALL SNOW TOWARD
EVENING BEFORE DIMINISHING. FARTHER EAST THERE WILL MORE WARM
ADVECTION AND MOSTLY TO ALL RAIN EAST OF I-71 SATURDAY. WITH THE
PASSAGE OF THE LOW TO THE NORTH AND TRAILING COLD FRONT COLD AIR
WILL SWEEP ACROSS THE REGION AND CHANGE ANY LINGERING
PRECIPITATION TO SNOW. IN THE SNOWBELT EAST OF CLE LAKE
ENHANCE/LAKE EFFECT SNOW CAN BE EXPECTED SATURDAY NIGHT AND
MAINLY EARLY SUNDAY WITH THE POTENTIAL FOR SEVERAL INCHES OF
SNOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
STRONG LOW PRESSURE WILL BE EXITING THE REGION TO THE NORTHEAST AT
THE START OF THE PERIOD. HIGH PRESSURE WILL QUICKLY BUILD IN FROM
THE SOUTHWEST ON SUNDAY. SOME LAKE EFFECT PRECIP COULD OCCUR SUNDAY
IN THE WESTERLY FLOW. DRIER AIR SHOULD EVENTUALLY WORK IN FROM THE
SOUTHWEST SUNDAY NIGHT AND EVENTUALLY CUT THE PRECIP OFF. THE HIGH
WILL CONTINUE TO BUILD OVER THE REGION FOR THE START OF THE WORKWEEK
KEEPING THE WEATHER DRY. THE MODELS BEGIN TO DIVERGE ON WEDNESDAY
WITH THE GFS DEVELOPING SOME WARM AIR ADVECTION PRECIP BY THE END OF
THE PERIOD. THE ECMWF KEEPS THE HIGH OVERHEAD A WHILE LONGER AND
WILL GO ALONG WITH IT`S DRY SCENARIO. TEMPS WILL AVERAGE A LITTLE
BELOW NORMAL FOR THE PERIOD.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A FEW SHOWERS HAVE REACHED THE WESTERN END OF THE AREA. THE ONE
OVER KTOL SHOULD BE GONE IN A FEW MINUTES. THE MAIN SHOW WILL
BEGIN IN A COUPLE OF HOURS. DO NOT EXPECT THE SHOWERS TO REACH
KCLE AND KMFD TILL AFTER DARK. SOME CONFLICT IN THE GUIDANCE ABOUT
LOWER CLOUDS. HAVE ADDED A TEMPO MENTION FOR THE EVENING HOURS
MOST AREAS. THE NORTHERN SITES WILL HAVE A BETTER CHANCE FOR THE
LOWER CLOUDS. ONCE THE PRECIP BEGINS IT WILL LAST 4 TO 6 HOURS
MOST AREAS. WINDS ARE ABOUT AS STRONG AS THEY WILL GET EXCEPT AT
KERI WHERE SOME INCREASE IS LIKELY TOWARD EVENING. BY 22Z PEAK
WINDS EXCEPT AT KERI WILL BE NO MORE THAN 32 TO 35 KNOTS.
OUTLOOK...NON VFR POSSIBLE IN THE SNOWBELT THURSDAY AND AGAIN
SATURDAY AND SUNDAY.
&&
.MARINE...
NO CHANGES TO THE HEADLINES ALTHOUGH WAS TEMPTED TO DROP
THE GALE WARNING. WINDS ARE EXPECTED TO COME UP A LITTLE SO WILL
GIVE IT A FEW MORE HOURS. WINDS ACTUALLY MAY BE STRONGER ON
THURSDAY IN THE SOUTHWEST FLOW BEHIND THE OCCLUDED FRONT. HIGH
PRESSURE WILL BEGIN TO BUILD OVER THE REGION FROM THE SOUTHWEST AND
THEN SOUTH LATE THURSDAY AND FRIDAY. THE FLOW WILL BECOME WEST AND
DIMINISH AS THIS OCCURS. AN AREA OF LOW PRESSURE WILL MOVE
NORTHEAST ACROSS THE LAKE ON SATURDAY EVENING. INCREASING SOUTHERLY
FLOW IS EXPECTED AHEAD OF THE LOW WITH POSSIBLE WESTERLY GALES
BEHIND THE SYSTEM. LATER CREWS WILL HAVE TO WATCH THAT. ANOTHER
HIGH WILL BUILD IN FROM THE SOUTH FOR THE SECOND HALF OF THE WEEKEND
AND START OF THE NEW WORKWEEK.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR PAZ001.
MARINE...GALE WARNING UNTIL 4 AM EST THURSDAY FOR LEZ061-149-169.
SMALL CRAFT ADVISORY UNTIL 4 AM EST THURSDAY FOR LEZ147-148.
SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ142>146.
&&
$$
SYNOPSIS...LAPLANTE
NEAR TERM...LAPLANTE
SHORT TERM...LAPLANTE
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1036 AM EST WED NOV 18 2015
.SYNOPSIS...
HIGH PRESSURE OVER NEW ENGLAND WILL MOVE OFF THE EAST COAST
TODAY...ALLOWING A STRONG COLD FRONT TO MOVE ACROSS THE FORECAST
AREA THIS AFTERNOON. A SECONDARY COLD FRONT WILL SWEEP ACROSS THE
AREA TOMORROW. HIGH PRESSURE WILL MOVE INTO THE OHIO VALLEY LATE
THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE MADE ONLY SMALL CHANGES TO THE FORECAST FOR THE AFTERNOON.
EXPECT WINDS TO INCREASE TODAY AHEAD OF A COLD FRONT. CURRENTLY WE
EXPECT DOWNSLOPING WINDS TO INCREASE ALONG THE LAKE ERIE SHORELINE
EAST OF CLE TO ESPECIALLY THE ERIE PA REGION. IN ADDITION SOME
MESOSCALE MODELS ARE ALSO PREDICTING WINDS TO INCREASE ALONG AND
WEST OF I-71 WITH GUSTS IN THE WIND ADVISORY CAT OF 40-50 KNOTS.
MFD WINDS HAVE INCREASED AND SOME THIN SPOTS/BREAKS IN THE CLOUD
COVER ARE SPREADING OVER THIS REGION. THE HRRR HAS THE HIGHEST
WINDS AHEAD OF THE CONVECTIVE LINE. ILN 12UTC SOUNDING HAD 50-70
KNOTS BELOW 850 MB. WILL CONSIDER EXPANDING THE WIND ADVISORY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
MODELS IN GOOD AGREEMENT MOVING THE FRONT EAST OF THE AREA
TONIGHT...WITH A WEAK SECONDARY FRONT SWEEPING ACROSS THE LAKES
TOMORROW. DO NOT EXPECT MUCH IN THE WAY OF RAIN WITH THIS SYSTEM AS
IT IS MOISTURE STARVE. IT WILL USHER IN MUCH MORE SEASONAL
TEMPERATURES FOR THE REMAINDER OF THE WEEK.
MODELS CONTINUE IN GOOD AGREEMENT WITH HIGH PRESSURE MOVING ACROSS
THE OHIO VALLEY LATE THURSDAY...FINALLY MOVING OFF THE MID
ATLANTIC COAST FRIDAY NIGHT.
STILL SOME DIFFERENCES ON THE TRACK AND TIMING OF THE SYSTEM THIS
SATURDAY. GFS CONTINUES TO BE THE FASTER AND FURTHER NORTH WITH THE
SYSTEM THAN THE ECMWF. THE GFS HAS THE SYSTEM INTO NW OHIO BY
DAYBREAK SATURDAY WHILE THE ECMWF HAS THE LOW BACK IN ILLINOIS.
BECAUSE OF THE DIFFERENCES SEE NO REASON TO CHANGE CURRENT FORECAST
OF RAIN OR SNOW SHOWERS LIKELY.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
THE LONG TERM BEGINS WITH THE GFS AND ECMWF DIFFERING ON THE DETAILS
SUNDAY BUT IN GENERAL AGREEMENT THAT AN UPPER LOW WILL BE OVER SRN
ONTARIO OR QUEBEC WITH A SURFACE LOW IN THE SAME GENERAL AREA.
INTENSITIES ALSO VARY ALTHOUGH THE BIG TAKE AWAY IS THAT
TEMPERATURES WILL BE MUCH COLDER WITH 850MB TEMPS -8 TO -12C WITH A
WEST FLOW OVER A FAIRLY WARM LAKE ERIE. MAIN THREAT FOR THE
PERIOD WILL BE LAKE EFFECT PRECIP. FORECAST SOUNDINGS FOR SUNDAY
SHOW EXTREME INSTABILITY TO THE LAKE WITH ONSHORE FLOW ACROSS NERN
OHIO AND NWRN PA. WILL HAVE LIKELY POPS FOR SNOW ACROSS THE
SNOWBELT. BY MONDAY HOWEVER THE INVERSION WILL BE LOWERING AND DRY
AIR SHOULD BE MOVING IN AS HIGH PRESSURE MOVES INTO THE OHIO VALLEY
SO WILL DROP POPS INTO THE CHANCE CATEGORY. TUESDAY HIGH PRESSURE
WILL BE OVER THE AREA SO WILL GO WITH A DRY FORECAST. FOR A CHANGE
TEMPS WILL BE BELOW NORMAL.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
EXPECT GUSTY SSE WINDS TODAY. GUSTS TO AROUND 30 KNOTS SHOULD BE
COMMON THROUGH THE DAY AND INTO THE EVENING. HIGHEST GUSTS NEAR
THE KERI LAKESHORE WHERE GUSTS TO 45-50KNOTS POSSIBLE. RAIN WILL
MOVE IN FROM THE WEST MAINLY THIS AFTERNOON AND TRACK EAST ACROSS
THE REGION. GUIDANCE SPLIT ON MVFR VS VFR THROUGH THE PERIOD AS
THE RAIN MOVES THROUGH. FOR NOW KEPT FORECAST VFR THROUGH THE DAY
BUT SHOULD BE CLOSE WHEN RAIN MOVES THROUGH.
OUTLOOK...NON VFR POSSIBLE IN THE SNOWBELT THURSDAY AND AGAIN
SATURDAY AND SUNDAY.
&&
.MARINE...
TRICKY NEAR TERM MARINE FORECAST. WINDS INCREASING
ACROSS THE AREA AS THE GRADIENT TIGHTENS BETWEEN HIGH PRESSURE IN
NORTHERN NEW ENGLAND AND LOW PRESSURE MOVING THROUGH MN EARLY TODAY
INTO WRN ONTARIO. SOUTHEAST WINDS ARE WARMER THAN THE WATER AND FOR
THE MOST PART SHOULD LOOSE MOMENTUM QUICKLY AS THEY MOVE OVER THE
WATER. HOWEVER...LOW LEVEL FLOW INCREASES TO OVER 60S KNOTS LATER
TODAY JUST BELOW 2KFT. DUE TO TERRAIN AFFECTS...THIS INCREASES WINDS
ALONG THE ERIE LAKESHORE. WINDS ALREADY GUSTING TO 37 KNOTS AT ERIE
AND SHOULD INCREASE FURTHER THROUGH THE DAY. THIS SHOULD GET ONTO
THE LAKE AND WILL LIKELY RESULT IN GALES ESPECIALLY ALONG THE ERIE
NEARSHORE. BROUGHT GALES IN AT 15Z AND CONTINUED THEM THROUGH 9Z
THURSDAY. A SMALL CRAFT ADVISORY MAY BE NEEDED LATE TONIGHT AS WINDS
DECREASE FROM GALES BUT WITH SOUTH WINDS CONTINUING AM EXPECTING
WAVES TO BE NOT ABOVE 4 FEET IN MOST OF THE NEARSHORE. THURSDAY
AFTERNOON HOWEVER A COLD FRONT ASSOCIATED WITH THE LOW WILL MOVE
EAST ACROSS THE LAKE TURNING WINDS FROM THE SOUTHWEST AT ABOUT 30
KNOTS. WILL NEED TO BRING THE SMALL CRAFT BACK AND THERE IS A
POSSIBILITY FOR GALES A FEW HOURS IN THE LATE AFTERNOON OR EARLY
EVENING. HIGH PRESSURE BUILDS OVER THE LAKE FRIDAY AND FRIDAY NIGHT.
SATURDAY MODELS DIFFER BUT AT THIS TIME AM EXPECTING WINDS TO
INCREASE FROM THE SOUTHWEST AS ANOTHER LOW MOVES THROUGH THE LAKES.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR OHZ003-006>012-
017>020-027>031-036>038-047-089.
PA...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ002.
HIGH WIND WARNING UNTIL 10 PM EST THIS EVENING FOR PAZ001.
MARINE...GALE WARNING UNTIL 4 AM EST THURSDAY FOR LEZ061-149-169.
SMALL CRAFT ADVISORY UNTIL 4 AM EST THURSDAY FOR LEZ147-148.
SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ142>146.
&&
$$
SYNOPSIS...DJB
NEAR TERM...LAPLANTE
SHORT TERM...DJB
LONG TERM...TK
AVIATION...TK
MARINE...TK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1016 AM EST WED NOV 18 2015
.SYNOPSIS...
HIGH PRESSURE OVER NEW ENGLAND WILL MOVE OFF THE EAST COAST
TODAY...ALLOWING A STRONG COLD FRONT TO MOVE ACROSS THE FORECAST
AREA THIS AFTERNOON. A SECONDARY COLD FRONT WILL SWEEP ACROSS THE
AREA TOMORROW. HIGH PRESSURE WILL MOVE INTO THE OHIO VALLEY LATE
THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE MADE ONLY SMALL CHANGES TO THE FORECAST FOR THE AFTERNOON.
EXPECT WINDS TO INCREASE TODAY AHEAD OF A COLD FRONT. CURRENTLY WE
EXPECT DOWNSLOPING WINDS TO INCREASE ALONG THE LAKE ERIE SHORELINE
EAST OF CLE TO ESPECIALLY THE ERIE PA REGION. IN ADDITION SOME
MESOSCALE MODELS ARE ALSO PREDICTING WINDS TO INCREASE ALONG AND
WEST OF I-71 WITH GUSTS IN THE WIND ADVISORY CAT OF 40-50 KNOTS.
MFD WINDS HAVE INCREASED AND SOME THIN SPOTS/BREAKS IN THE CLOUD
COVER ARE SPREADING OVER THIS REGION. THE HRRR HAS THE HIGHEST
WINDS AHEAD OF THE CONVECTIVE LINE. ILN 12UTC SOUNDING HAD 50-70
KNOTS BELOW 850 MB. WILL CONSIDER EXPANDING THE WIND ADVISORY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
MODELS IN GOOD AGREEMENT MOVING THE FRONT EAST OF THE AREA
TONIGHT...WITH A WEAK SECONDARY FRONT SWEEPING ACROSS THE LAKES
TOMORROW. DO NOT EXPECT MUCH IN THE WAY OF RAIN WITH THIS SYSTEM AS
IT IS MOISTURE STARVE. IT WILL USHER IN MUCH MORE SEASONAL
TEMPERATURES FOR THE REMAINDER OF THE WEEK.
MODELS CONTINUE IN GOOD AGREEMENT WITH HIGH PRESSURE MOVING ACROSS
THE OHIO VALLEY LATE THURSDAY...FINALLY MOVING OFF THE MID
ATLANTIC COAST FRIDAY NIGHT.
STILL SOME DIFFERENCES ON THE TRACK AND TIMING OF THE SYSTEM THIS
SATURDAY. GFS CONTINUES TO BE THE FASTER AND FURTHER NORTH WITH THE
SYSTEM THAN THE ECMWF. THE GFS HAS THE SYSTEM INTO NW OHIO BY
DAYBREAK SATURDAY WHILE THE ECMWF HAS THE LOW BACK IN ILLINOIS.
BECAUSE OF THE DIFFERENCES SEE NO REASON TO CHANGE CURRENT FORECAST
OF RAIN OR SNOW SHOWERS LIKELY.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
THE LONG TERM BEGINS WITH THE GFS AND ECMWF DIFFERING ON THE DETAILS
SUNDAY BUT IN GENERAL AGREEMENT THAT AN UPPER LOW WILL BE OVER SRN
ONTARIO OR QUEBEC WITH A SURFACE LOW IN THE SAME GENERAL AREA.
INTENSITIES ALSO VARY ALTHOUGH THE BIG TAKE AWAY IS THAT
TEMPERATURES WILL BE MUCH COLDER WITH 850MB TEMPS -8 TO -12C WITH A
WEST FLOW OVER A FAIRLY WARM LAKE ERIE. MAIN THREAT FOR THE
PERIOD WILL BE LAKE EFFECT PRECIP. FORECAST SOUNDINGS FOR SUNDAY
SHOW EXTREME INSTABILITY TO THE LAKE WITH ONSHORE FLOW ACROSS NERN
OHIO AND NWRN PA. WILL HAVE LIKELY POPS FOR SNOW ACROSS THE
SNOWBELT. BY MONDAY HOWEVER THE INVERSION WILL BE LOWERING AND DRY
AIR SHOULD BE MOVING IN AS HIGH PRESSURE MOVES INTO THE OHIO VALLEY
SO WILL DROP POPS INTO THE CHANCE CATEGORY. TUESDAY HIGH PRESSURE
WILL BE OVER THE AREA SO WILL GO WITH A DRY FORECAST. FOR A CHANGE
TEMPS WILL BE BELOW NORMAL.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
EXPECT GUSTY SSE WINDS TODAY. GUSTS TO AROUND 30 KNOTS SHOULD BE
COMMON THROUGH THE DAY AND INTO THE EVENING. HIGHEST GUSTS NEAR
THE KERI LAKESHORE WHERE GUSTS TO 45-50KNOTS POSSIBLE. RAIN WILL
MOVE IN FROM THE WEST MAINLY THIS AFTERNOON AND TRACK EAST ACROSS
THE REGION. GUIDANCE SPLIT ON MVFR VS VFR THROUGH THE PERIOD AS
THE RAIN MOVES THROUGH. FOR NOW KEPT FORECAST VFR THROUGH THE DAY
BUT SHOULD BE CLOSE WHEN RAIN MOVES THROUGH.
OUTLOOK...NON VFR POSSIBLE IN THE SNOWBELT THURSDAY AND AGAIN
SATURDAY AND SUNDAY.
&&
.MARINE...
TRICKY NEAR TERM MARINE FORECAST. WINDS INCREASING
ACROSS THE AREA AS THE GRADIENT TIGHTENS BETWEEN HIGH PRESSURE IN
NORTHERN NEW ENGLAND AND LOW PRESSURE MOVING THROUGH MN EARLY TODAY
INTO WRN ONTARIO. SOUTHEAST WINDS ARE WARMER THAN THE WATER AND FOR
THE MOST PART SHOULD LOOSE MOMENTUM QUICKLY AS THEY MOVE OVER THE
WATER. HOWEVER...LOW LEVEL FLOW INCREASES TO OVER 60S KNOTS LATER
TODAY JUST BELOW 2KFT. DUE TO TERRAIN AFFECTS...THIS INCREASES WINDS
ALONG THE ERIE LAKESHORE. WINDS ALREADY GUSTING TO 37 KNOTS AT ERIE
AND SHOULD INCREASE FURTHER THROUGH THE DAY. THIS SHOULD GET ONTO
THE LAKE AND WILL LIKELY RESULT IN GALES ESPECIALLY ALONG THE ERIE
NEARSHORE. BROUGHT GALES IN AT 15Z AND CONTINUED THEM THROUGH 9Z
THURSDAY. A SMALL CRAFT ADVISORY MAY BE NEEDED LATE TONIGHT AS WINDS
DECREASE FROM GALES BUT WITH SOUTH WINDS CONTINUING AM EXPECTING
WAVES TO BE NOT ABOVE 4 FEET IN MOST OF THE NEARSHORE. THURSDAY
AFTERNOON HOWEVER A COLD FRONT ASSOCIATED WITH THE LOW WILL MOVE
EAST ACROSS THE LAKE TURNING WINDS FROM THE SOUTHWEST AT ABOUT 30
KNOTS. WILL NEED TO BRING THE SMALL CRAFT BACK AND THERE IS A
POSSIBILITY FOR GALES A FEW HOURS IN THE LATE AFTERNOON OR EARLY
EVENING. HIGH PRESSURE BUILDS OVER THE LAKE FRIDAY AND FRIDAY NIGHT.
SATURDAY MODELS DIFFER BUT AT THIS TIME AM EXPECTING WINDS TO
INCREASE FROM THE SOUTHWEST AS ANOTHER LOW MOVES THROUGH THE LAKES.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR OHZ012-089.
PA...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR PAZ002.
HIGH WIND WARNING UNTIL MIDNIGHT EST TONIGHT FOR PAZ001.
MARINE...GALE WARNING UNTIL 4 AM EST THURSDAY FOR LEZ061-149-169.
SMALL CRAFT ADVISORY UNTIL 4 AM EST THURSDAY FOR LEZ147-148.
SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ142>146.
&&
$$
SYNOPSIS...DJB
NEAR TERM...LAPLANTE
SHORT TERM...DJB
LONG TERM...TK
AVIATION...TK
MARINE...TK
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
930 AM EST WED NOV 18 2015
.SYNOPSIS...
COLD FRONT CROSSES OVERNIGHT INTO EARLY THURSDAY MORNING. ANOTHER
COLD FRONT THURSDAY NIGHT SANDWICHED BETWEEN HIGHS THURSDAY AND
FRIDAY. MUCH COLDER AIR ARRIVES SATURDAY NIGHT INTO SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
925 AM UPDATE...
THE INVERSION STILL LINGERING OVER PORTIONS OF THE LOWLANDS.
HOWEVER...WIND GUSTS WILL BE PICKING UP BY 16Z. THOUGH GUSTS MAY
NOT TECHNICALLY REACH 40 KT CRITERIA...STILL EXPECTING STRONG
GUSTS ON THE ORDER OF 30 TO 35 KTS. SO THE ADVISORY CONTINUES AS
IS. REWORKED THE GRIDS USING LATEST HRRR AS A BASE. THIS DELAYS
PREFRONTAL BAND A HR OR SO FROM PREVIOUS FORECAST. KEPT MAINLY DRY
CONDITIONS AHEAD OF THIS GIVEN STRONG DOWNSLOPING. EXCEPTION BEING
E SLOPES OF RANDOLPH AND INTO POCAHONTAS COUNTIES WHERE SOME
PATCHY DZ WILL BE POSSIBLE THRU MIDDAY. RAISED MAXT A FEW TICKS
ESPECIALLY ALONG I 79 CORRIDOR WHERE COMPRESSIONAL WARMING EFFECTS
FROM DOWNSLOPING FLOW ARE MAXIMIZED. SOME MID TO PERHAPS UPPER 70S
POSSIBLE HERE.
PREVIOUS DISCUSSION BELOW...
ACTIVE WEATHER IN THE NEAR TERM PERIOD. GUSTY WINDS TODAY AND
TONIGHT OUT AHEAD OF AN APPROACHING COLD FRONT...PARTICULARLY ACROSS
RIDGE TOPS...AND WV LOWLANDS IN FAVORED DOWNSLOPING AREAS IN THE
STRONG SOUTHEASTERLY FLOW. DECIDED TO GO AHEAD AND ADD
RANDOLPH...POCAHONTAS...AND BARBOUR COUNTIES TO THE WIND
ADVISORY...WITH RANDOLPH AND POCAHONTAS COUNTIES DROPPING OFF LATER
IN THE EVENING AS SOME GUSTS SHOULD CONTINUE WELL INTO THE EVENING
THERE AS THE FRONT CROSSES THROUGH THE REGION.
COLD FRONT WILL BE ENTERING CWA LATE TONIGHT...EXITING TO THE EAST
OF THE MOUNTAINS EARLY THURSDAY MORNING. STRONG LLJ...ON THE ORDER
OF 60+ KTS...WILL AID IN MOISTURE TRANSPORT TO THE AREA...WITH PW
VALUES PROGGED TO RISE TO AROUND 1.6 INCHES. EXPECTING HEAVY RAIN
LATER TONIGHT WITH THE FRONT. OUT AHEAD OF THE FRONT...EXPECTING
SOME -DZ OR -SHRA DEVELOPING TODAY ACROSS THE MOUNTAINS IN SE
UPSLOPE AREAS.
WITH THE STRONG DOWNSLOPING WINDS...TEMPERATURES TODAY WILL BE EVEN
WARMER THAN TUESDAY...PARTICULARLY ACROSS THE WV LOWLANDS...AND HAVE
TEMPERATURES TODAY TOPPING OUT IN THE LOWER TO MID 70S ACROSS MUCH
OF THE LOWLANDS TODAY.
FRONTAL BOUNDARY WILL EXIT TO THE EAST OF THE CWA TOWARDS THE END OF
THE PERIOD...WITH A GRADUAL DRYING TREND FROM WEST TO EAST. SOME
DECREASE IN WINDS TOWARDS MORNING...BUT STILL OCCASIONALLY GUSTY AT
TIMES.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
LATEST MODEL RUNS INDICATE A COLD FRONT WILL BE EXITING EAST OF
THE EASTERN MOUNTAINS EARLY THURSDAY MORNING. LINGERING LIGHT RAIN
SHOWERS WILL BE POSSIBLE BEHIND THE FRONT.
HIGH PRESSURE BUILDS BEHIND THE FRONT FROM THE SOUTHERN GULF
STATES...NORTH NORTHEAST INTO WV TO PROVIDE DRY CONDITIONS
THURSDAY NIGHT AND FRIDAY.
A SFC LOW PRESSURE DEVELOPS ACROSS THE SOUTHERN PLAINS AND TRACKS
NORTHEAST ACROSS THE OH VALLEY AND WV. THIS SYSTEM WILL BRING
ANOTHER COLD FRONT PASSING QUICKLY EAST ON SATURDAY.
HOWEVER...LIMITED MOISTURE WILL KEEP PCPN ON THE LIGHT SIDE.
ALTHOUGH LOW LEVEL TEMPERATURES WILL BE SLIGHTLY ABOVE
FREEZING...SNOW MIXED WITH RAIN...OR LIGHT SNOW SHOWERS WILL BE
POSSIBLE SATURDAY AND SATURDAY NIGHT.
PREVIOUS TEMPERATURES SIMILAR TO THE SUPER BLEND AND NATIONAL
BLEND OF MODELS GUIDANCE THROUGH THE PERIOD. EXPECT A COOLING
TREND THROUGH THE WEEKEND.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
THE NORTHERN BRANCH 500 MB TROF DIVES ESE FROM THE NORTHERN PLAINS
FRIDAY NIGHT TO WHIP THRU THE UPPER OHIO VALLEY SATURDAY EVENING. OF
COURSE... MOISTURE MUCH MORE LIMITED...PRECIPITABLE WATER BELOW 0.75
INCHES. THINKING DYNAMICS ENOUGH FOR SOME FAST MOVING RAIN
SHOWERS...SO INCREASE POPS IN THE SOUTHERN COUNTIES. AS A
RESULT...THE CHANCE POP CATEGORY MORE WIDESPREAD FOR SATURDAY
COMPARED TO 24 HOURS.
MUCH COLDER AIR IN ITS WAKE WITH 850 TEMPS OF MINUS 10 TO MINUS 12C.
SO WENT COLDER FOR TEMPS FOR SATURDAY NIGHT AND SUNDAY...WITH TEENS
AOA 4000 FEET FOR DAWN SUNDAY. HAD SOME LIKELY POPS FOR SQUEEZING
OUT THE SNOW SHOWERS SATURDAY NIGHT OVER OUR WV CENTRAL
MOUNTAINS...WITH SOME OF THE WESTERN LOWLANDS FINALLY SEEING THEIR
FIRST FLAKES OF THE NEW SEASON.
12Z GFS HOLD MORE LOW LEVEL MOISTURE LONGER MONDAY INTO TUESDAY.
TRENDED LESS...SINCE THE 850 MB THERMAL TROF SHOULD HAVE PASSED BY
SUNDAY NIGHT.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
MAINLY VFR CONDITIONS THROUGH 22Z...ALTHOUGH SOME LOCAL MVFR CIGS
POSSIBLE ACROSS THE MOUNTAINS INCLUDING AT SITES KBKW IN THE
SOUTHEASTERLY UPSLOPE FLOW...AND -DZ.
STRONG SOUTHEASTERLY WINDS EXPECTED TODAY AREA WIDE...WITH
SUSTAINED WINDS IN THE TEENS...WITH GUSTS IN THE 20-30 KT
RANGE...WITH OCCASIONAL GUSTS OVER 40 KTS NOT OUT OF THE
QUESTION...PARTICULARLY ACROSS SOUTHWEST VIRGINIA...CENTRAL AND
SOUTHERN WEST VIRGINIA...AND NORTHEAST KENTUCKY.
A STRONG COLD FRONT WILL ENTER SOUTHEAST OHIO AROUND 00Z. EXPECT
+SHRA...AND THE GRADUAL DEVELOPMENT OF WIDESPREAD MVFR AND LOCAL
IFR CONDITIONS AREA WIDE AFTER 00Z. IN ADDITION...STRONG GUSTY
WINDS WILL ACCOMPANY FRONTAL PASSAGE.
SHRA WILL GRADUALLY TAPER OFF FROM WEST TO EAST AFTER
06-09Z...WITH WIDESPREAD MVFR AND LOCAL IFR CIGS LINGERING.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z THURSDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: TIMING OF PRECIPITATION LATER TODAY AND
TONIGHT AND ASSOCIATED DETERIORATING CONDITIONS MAY VARY FROM
FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 12 13 14 15 16 17 18 19 20 21 22 23
EST 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY M M M M M H H M M M M M
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z THURSDAY...
IFR POSSIBLE IN RAIN SHOWERS INTO THURSDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ005>008-
013>018-024>030-033>040.
WIND ADVISORY UNTIL 11 PM EST THIS EVENING FOR WVZ046-047.
OH...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR OHZ086-087.
KY...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR KYZ101>103-105.
VA...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR VAZ003-004.
&&
$$
SYNOPSIS...ARJ/SL
NEAR TERM...SL/30
SHORT TERM...ARJ
LONG TERM...KTB
AVIATION...SL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1043 PM EST THU NOV 19 2015
.SYNOPSIS...
A FRONT WILL CLEAR THE REGION THIS EVENING...BRINGING AN END TO
THE SHOWER ACTIVITY OVER CENTRAL AND EASTERN AREAS AND DECREASING
CLOUDS. FAIR WEATHER WILL PREVAIL TONIGHT AND FRIDAY AS SURFACE
HIGH PRESSURE BUILDS ACROSS THE REGION...ACCOMPANIED BY COOLER AND
MORE SEASONABLE TEMPERATURES. ANOTHER FRONT WILL CROSS THE REGION
SATURDAY NIGHT AND SUNDAY...WITH A BRISK AND COLDER WEATHER
PATTERN WILL ARRIVING FOR SUNDAY AND LASTING INTO EARLY NEXT
WEEK...FOLLOWED BY MILDER WEATHER FOR THANKSGIVING.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
NOT A LOT OF CHANGE TO THE GRIDS.
MOST OF THE AREA CLEAR NOW...FEW CLOUDS ACROSS THE FAR WEST.
MORE IN THE WAY OF CLOUDS ACROSS THE EAST.
SOME GUSTY WINDS AT THE OFFICE FOR A BRIEF TIME...BUT MOST OF
THE AREA NOT SEEING MUCH WIND. FAR WESTERN AREAS LIKE BFD AND JST
ON THE GUSTY SIDE.
MAIN CHANGE WAS TO ADD SOME PATCHY FOG TO THE EASTERN AREAS
FOR A FEW HOURS. WINDS NW AT MDT BUT SW AT CXY. EXPECT WINDS
TO SLOWLY PICK UP ACROSS THE EAST OVERNIGHT.
ALSO TOOK OUT CHC OF SHOWERS ACROSS THE FAR NW EARLIER THIS
EVENING.
EARLIER DISCUSSION BELOW.
OCCLUDED FRONT PUSHING THROUGH THE CENTRAL MOUNTAINS AT MID
AFTERNOON. RAPID CLEARING PUSHING INTO THE CENTRAL MOUNTAINS AS
MUCH DRIER WSW FLOW ARRIVES BEHIND THE FROPA. STILL EXPECT A FEW
TO SEVERAL MORE HOURS OF SHOWERS ACROSS MY FAR EAST AS THE FRONT
WILL BE SLOWEST TO CLEAR THE LOWER SUSQ RIVER VALLEY.
SFC RIDGE AXIS BUILDS OVER CENTRAL PA TONIGHT FOR AT LEAST PARTLY
CLOUDY SKIES IN MOST AREAS. SOME LAKE CLOUDS MAY HOLD ON ACROSS
THE LAKE ERIE SHORELINE AND EXTENDING INTO FAR WESTERN WARREN
COUNTY. THE SOUTHEAST WILL CLEAR AFTER MIDNIGHT. MINS WILL BE
LOWER BY SEVERAL DEGREES THAN RECENT NIGHTS...RANGING FROM THE
UPPER 20S NORTHWEST TO THE LOWER 40S SOUTHEAST.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
A RATHER NICE DAY IS IN STORE FOR MOST OF CENTRAL PA ON
FRIDAY...AHEAD OF A DEEP STORM SYSTEM AFFECTING THE UPPER MIDWEST
AND WESTERN GREAT LAKES. SFC HIGH BUILDS INTO SOUTHERN OH AND THE
WV PANHANDLE BY 00Z SAT...BACKING BOUNDARY LAYER FLOW TO THE WNW
THROUGHOUT THE DAY AND ADVECTING IN COOLER AIR AT 850. IT SHOULD
BE WELL MIXED HOWEVER...WHICH WILL ALLOW MAXES TO REACH THE LOWER
40S NORTHWEST AND MID 40S TO LOWER 50S CENTRAL AND SOUTHEAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
ADJUSTED PRECIPITATION TYPE FOR LATE SATURDAY NIGHT...GIVEN
FCST LOW TEMPERATURES.
EARLIER DISCUSSION BELOW.
EXPECT AN INCREASE IN MID LVL CLOUDINESS FRI NIGHT...ESP OVER THE
NW COUNTIES...AS WAA DEVELOPS AHEAD OF LOW PRES LIFTING THRU THE
MIDWEST. AN ARM OF OVERRUNNING PRECIP IS PROGGED BY MDLS TO BE
LIFTING THRU THE E GRT LKS EARLY SAT ALONG DEVELOPING WARM FRONT.
HAVE INCLUDED A SLIGHT CHC OF SHSN ACROSS THE NW MTNS AS 850MB
BAROCLINIC ZONE LIFTS THRU EARLY SAT AM.
ANY THREAT OF AM SHSN OVR THE NW MTNS SHOULD END BY SAT AFTN...AS
8H BAROCLINIC ZONE LIFTS NORTH OF THE STATE. OTHERWISE...ALL
LATEST MDL DATA POINTING TOWARD A FAIR AND SEASONABLE SATURDAY
WITH REGION BENEATH UPPER LVL RIDGING AHEAD OF POTENT SHORTWAVE OF
THE MIDWEST. THE MODELS CONTINUE TO STALL THE FRONT AND THE
PRECIPITATION. EXPECT THE SFC LOW TO INTENSIFYING NORTH OF PA SAT
NIGHT. THE GEFS AND NAEFS ENSEMBLES ARE SHOWING A BETTER CONSENSUS
AS FAR AS WHAT WILL HAPPEN...THOUGH TIMING IS STILL INCONSISTENT.
SO THE TRAILING COLD FRONT WILL LIKELY BE ACCOMPANIED BY SCT RAIN
SHOWERS ACROSS THE AREA SAT NIGHT. HOWEVER...GIVEN MDL THERMAL
PROFILES...CAN/T RULE OUT A BIT OF WET SNOW ACROSS THE NW MTNS.
MED RANGE GUIDANCE REMAINS IN GENERAL AGREEMENT SUN-MON...ALL
INDICATING AN ANOMALOUS UPPER TROF PIVOTING ACROSS THE NORTHEAST
CONUS. CHILLY NW FLOW CROSSING THE STILL MILD GRT LKS SHOULD
SUPPORT LE SNOW SHOWERS OVR THE NW MTNS SUNDAY INTO EARLY MONDAY.
A STRETCH OF FAIR AND INCREASINGLY MILD WX THEN APPEARS VERY
LIKELY NEXT WEEK...BASED ON 00Z NAEFS/ECENS SHOWING TROUGH
LIFTING OUT AND DEVELOPMENT OF AN ANOMALOUS RIDGE OVR THE EASTERN
CONUS LATER IN THE WEEK.
&&
.AVIATION /04Z FRIDAY THROUGH TUESDAY/...
COLD FRONT HAS SWEPT RAIN EAST OF CENTRAL PENNSYLVANIA AIRFIELDS
THIS EVENING. HOWEVER...LIGHT WINDS IN VICINITY OF THE FRONT IN
EASTERN AREAS HAVE ALLOWED FOR RAPID FOG AND LOW CIG FORMATION AT
KLNS...KMDT AND KSEG...KIPT...AND KTHV.
EXPECTING THAT ONCE THERE IS A PUSH OF WINDS INTO THE REGION FROM
THE WEST...WE WILL SEE A RAPID UPTICK IN CONDITIONS AT THESE
LOCATIONS TO VFR. HAVE TIMED THIS IMPROVEMENT TO AROUND
0230Z...BUT WILL HAVE TO SEE IF THIS MIGHT BE A LITTLE TOO
OPTIMISTIC. LATEST HRRR IMPLIES IMPROVEMENTS MIGHT NOT COME INTO
KMDT AND KLNS UNTIL AFTER 04Z.
ONCE WE CLEAR OUT THESE LOW CLOUDS IN THE EAST...EXPECT VFR
CONDITIONS OVERNIGHT THROUGH FRIDAY AND INTO SATURDAY.
OUTLOOK...
SAT NGT...SHRA CHANGING SHSN OVER THE WRN AIRSPACE.
SUN...MVFR CIGS WEST TO VFR EAST. IFR VIS PSBL NW IN SHSN.
MON...MVFR-VFR CIGS. NO SIG WX.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR/MARTIN
SHORT TERM...DEVOIR
LONG TERM...FITZGERALD/CERU/MARTIN
AVIATION...JUNG/DEVOIR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
823 PM EST THU NOV 19 2015
.SYNOPSIS...
A FRONT WILL CLEAR THE REGION THIS EVENING...BRINGING AN END TO
THE SHOWER ACTIVITY OVER CENTRAL AND EASTERN AREAS AND DECREASING
CLOUDS. FAIR WEATHER WILL PREVAIL TONIGHT AND FRIDAY AS SURFACE
HIGH PRESSURE BUILDS ACROSS THE REGION...ACCOMPANIED BY COOLER AND
MORE SEASONABLE TEMPERATURES. ANOTHER FRONT WILL CROSS THE REGION
SATURDAY NIGHT AND SUNDAY...WITH A BRISK AND COLDER WEATHER
PATTERN WILL ARRIVING FOR SUNDAY AND LASTING INTO EARLY NEXT
WEEK...FOLLOWED BY MILDER WEATHER FOR THANKSGIVING.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
SENDING OUT NEW ZONES TO INCLUDE TONIGHT AND DAY 7...THANKSGIVING.
NO NEED FOR REST OF THIS AFT...AS MOST OF THE SHOWERS NOW EAST
OF THE AREA.
EARLIER DISCUSSION BELOW.
OCCLUDED FRONT PUSHING THROUGH THE CENTRAL MOUNTAINS AT MID
AFTERNOON. RAPID CLEARING PUSHING INTO THE CENTRAL MOUNTAINS AS
MUCH DRIER WSW FLOW ARRIVES BEHIND THE FROPA. STILL EXPECT A FEW
TO SEVERAL MORE HOURS OF SHOWERS ACROSS MY FAR EAST AS THE FRONT
WILL BE SLOWEST TO CLEAR THE LOWER SUSQ RIVER VALLEY.
SFC RIDGE AXIS BUILDS OVER CENTRAL PA TONIGHT FOR AT LEAST PARTLY
CLOUDY SKIES IN MOST AREAS. SOME LAKE CLOUDS MAY HOLD ON ACROSS
THE LAKE ERIE SHORELINE AND EXTENDING INTO FAR WESTERN WARREN
COUNTY. THE SOUTHEAST WILL CLEAR AFTER MIDNIGHT. MINS WILL BE
LOWER BY SEVERAL DEGREES THAN RECENT NIGHTS...RANGING FROM THE
UPPER 20S NORTHWEST TO THE LOWER 40S SOUTHEAST.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
A RATHER NICE DAY IS IN STORE FOR MOST OF CENTRAL PA ON
FRIDAY...AHEAD OF A DEEP STORM SYSTEM AFFECTING THE UPPER MIDWEST
AND WESTERN GREAT LAKES. SFC HIGH BUILDS INTO SOUTHERN OH AND THE
WV PANHANDLE BY 00Z SAT...BACKING BOUNDARY LAYER FLOW TO THE WNW
THROUGHOUT THE DAY AND ADVECTING IN COOLER AIR AT 850. IT SHOULD
BE WELL MIXED HOWEVER...WHICH WILL ALLOW MAXES TO REACH THE LOWER
40S NORTHWEST AND MID 40S TO LOWER 50S CENTRAL AND SOUTHEAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
ADJUSTED PRECIPITATION TYPE FOR LATE SATURDAY NIGHT...GIVEN
FCST LOW TEMPERATURES.
EARLIER DISCUSSION BELOW.
EXPECT AN INCREASE IN MID LVL CLOUDINESS FRI NIGHT...ESP OVER THE
NW COUNTIES...AS WAA DEVELOPS AHEAD OF LOW PRES LIFTING THRU THE
MIDWEST. AN ARM OF OVERRUNNING PRECIP IS PROGGED BY MDLS TO BE
LIFTING THRU THE E GRT LKS EARLY SAT ALONG DEVELOPING WARM FRONT.
HAVE INCLUDED A SLIGHT CHC OF SHSN ACROSS THE NW MTNS AS 850MB
BAROCLINIC ZONE LIFTS THRU EARLY SAT AM.
ANY THREAT OF AM SHSN OVR THE NW MTNS SHOULD END BY SAT AFTN...AS
8H BAROCLINIC ZONE LIFTS NORTH OF THE STATE. OTHERWISE...ALL
LATEST MDL DATA POINTING TOWARD A FAIR AND SEASONABLE SATURDAY
WITH REGION BENEATH UPPER LVL RIDGING AHEAD OF POTENT SHORTWAVE OF
THE MIDWEST. THE MODELS CONTINUE TO STALL THE FRONT AND THE
PRECIPITATION. EXPECT THE SFC LOW TO INTENSIFYING NORTH OF PA SAT
NIGHT. THE GEFS AND NAEFS ENSEMBLES ARE SHOWING A BETTER CONSENSUS
AS FAR AS WHAT WILL HAPPEN...THOUGH TIMING IS STILL INCONSISTENT.
SO THE TRAILING COLD FRONT WILL LIKELY BE ACCOMPANIED BY SCT RAIN
SHOWERS ACROSS THE AREA SAT NIGHT. HOWEVER...GIVEN MDL THERMAL
PROFILES...CAN/T RULE OUT A BIT OF WET SNOW ACROSS THE NW MTNS.
MED RANGE GUIDANCE REMAINS IN GENERAL AGREEMENT SUN-MON...ALL
INDICATING AN ANOMALOUS UPPER TROF PIVOTING ACROSS THE NORTHEAST
CONUS. CHILLY NW FLOW CROSSING THE STILL MILD GRT LKS SHOULD
SUPPORT LE SNOW SHOWERS OVR THE NW MTNS SUNDAY INTO EARLY MONDAY.
A STRETCH OF FAIR AND INCREASINGLY MILD WX THEN APPEARS VERY
LIKELY NEXT WEEK...BASED ON 00Z NAEFS/ECENS SHOWING TROUGH
LIFTING OUT AND DEVELOPMENT OF AN ANOMALOUS RIDGE OVR THE EASTERN
CONUS LATER IN THE WEEK.
&&
.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
COLD FRONT HAS SWEPT RAIN EAST OF CENTRAL PENNSYLVANIA AIRFIELDS
THIS EVENING. HOWEVER...LIGHT WINDS IN VICINITY OF THE FRONT IN
EASTERN AREAS HAVE ALLOWED FOR RAPID FOG AND LOW CIG FORMATION AT
KLNS...KMDT AND KSEG...KIPT...AND KTHV.
EXPECTING THAT ONCE THERE IS A PUSH OF WINDS INTO THE REGION FROM
THE WEST...WE WILL SEE A RAPID UPTICK IN CONDITIONS AT THESE
LOCATIONS TO VFR. HAVE TIMED THIS IMPROVEMENT TO AROUND
0230Z...BUT WILL HAVE TO SEE IF THIS MIGHT BE A LITTLE TOO
OPTIMISTIC. LATEST HRRR IMPLIES IMPROVEMENTS MIGHT NOT COME INTO
KMDT AND KLNS UNTIL AFTER 04Z.
ONCE WE CLEAR OUT THESE LOW CLOUDS IN THE EAST...EXPECT VFR
CONDITIONS OVERNIGHT THROUGH FRIDAY AND INTO SATURDAY.
OUTLOOK...
SAT NGT...SHRA CHANGING SHSN OVER THE WRN AIRSPACE.
SUN...MVFR CIGS WEST TO VFR EAST. IFR VIS PSBL NW IN SHSN.
MON...MVFR-VFR CIGS. NO SIG WX.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR/MARTIN
SHORT TERM...DEVOIR
LONG TERM...FITZGERALD/CERU/MARTIN
AVIATION...JUNG/DEVOIR
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
908 PM CST THU NOV 19 2015
.UPDATE...
ISSUED AT 908 PM CST THU NOV 19 2015
UNTIL THE GFS COMES IN...IT IS HARD TO CHANGE HEADLINES. HOWEVER
HAVE PERUSED OVER THE NAM...AND ITS UPPER QG FORCING HAS DRIFTED
FURTHER SOUTH...MUCH CLOSER TO THE GFS AND ECMWF EARLIER. THE
CENTER OF THE QG FORCING TRACKS FROM SOUTHWEST SD AT 12Z
FRIDAY...TO SOUTHWEST IA AT 06Z SATURDAY. THE MID LEVEL
FRONTOGENESIS AT 750-700MB IS ALSO MAXIMIZED FIRST IN SOUTH
CENTRAL SD AT 12Z...THEN MOVES NEARLY DUE EASTWARD INTO THE HEART
OF NORTHWEST IA TOWARD SPENCER IN THE AFTERNOON. INSTABILITY IS
ABUNDANT AT 600MB ABOVE THE FRONTOGENESIS WITH A DEEP SATURATED
MOISTURE DEPTH. THE JET STREAKS HAVE NOT CHANGED. BELIEVE THE MAX
SNOW AMOUNTS COULD BE JUST NORTH OF SIOUX CITY...AND EXTENDING
OVER TO STORM LAKE...BUT IT DEPENDS ON HOW MUCH INSTABILITY WE
HAVE JUST ON THE SOUTHERN END OF THE FRONTOGENETIC BAND WHICH
COULD ADD TO TOTALS AT SIOUX CITY. ONE THING FOR SURE...IT COULD
REALLY SNOW HARD FOR A WHILE IN THE LATE MORNING AND AFTERNOON
JUST SOUTH OF I 90...WITH DECENT SNOW AMOUNTS ALONG I 90.
&&
.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
FRONTOGENETIC 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
INSTABILITY...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 FOCUS 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 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 529 PM CST THU NOV 19 2015
MAIN AVIATION CONCERN IS THE LATE MORNING AND AFTERNOON HOURS ON
FRIDAY...WHEN A BAND OF SNOW WILL MOVE ACROSS THE FORECAST...MOST
ACUTE ALONG INTERSTATE 90 AND SOUTHWARD. THEREFORE HAVE LIFR TO
IFR CONDITIONS FOR THE KFSD AND KSUX TAF SITES...KEEPING KHON AT
MVFR WHO SHOULD BE TOO FAR NORTH TO GET HEAVY SNOW.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER STORM WARNING FROM 6 AM TO 9 PM CST FRIDAY FOR SDZ068>071.
WINTER STORM WATCH FROM 6 AM CST FRIDAY THROUGH FRIDAY EVENING
FOR SDZ065>067.
WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST FRIDAY FOR SDZ050-
063-064.
MN...NONE.
IA...WINTER STORM WATCH FROM 6 AM CST FRIDAY 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.
&&
$$
UPDATE...MJ
SHORT TERM...
LONG TERM...
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
531 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
FRONTOGENETIC 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
INSTABILITY...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 FOCUS 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 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 529 PM CST THU NOV 19 2015
MAIN AVIATION CONCERN IS THE LATE MORNING AND AFTERNOON HOURS ON
FRIDAY...WHEN A BAND OF SNOW WILL MOVE ACROSS THE FORECAST...MOST
ACUTE ALONG INTERSTATE 90 AND SOUTHWARD. THEREFORE HAVE LIFR TO
IFR CONDITIONS FOR THE KFSD AND KSUX TAF SITES...KEEPING KHON AT
MVFR WHO SHOULD BE TOO FAR NORTH TO GET HEAVY SNOW.
&&
.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>040-053>056-
059>062-065>067-069>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...MJ
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
950 AM CST WED NOV 18 2015
.UPDATE...
FOR MORNING UPDATE.
&&
.DISCUSSION...
MODERATE TO HEAVY RAINS CONTINUE TO SLOWLY TRAVERSE MIDDLE
TENNESSEE THIS MORNING. VERY LITTLE THUNDER IS BEING SEEN AT THIS
TIME. MOST EVERYONE WILL SEE 1-2 INCHES BEFORE THIS EVENT IS
OVER. WINDS WILL CONTINUE TO GUST AHEAD OF AND WITH THE RAINS.
GUSTS OF 30 TO 35 MPH WILL BE COMMON THROUGH THE NOON HOUR. WILL
LET THE WIND ADVISORY EXPIRE AT NOON HOWEVER AS THE CRITERIA-
REACHING WINDS SHOULD BE OFF THE PLATEAU BY THEN.
RAINS WILL START TO TAPER OFF THROUGHOUT THE AFTERNOON HOURS FROM
WEST TO EAST AND I THINK SOME OF OUR FAR WESTERN COUNTIES ALONG
THE TENNESSEE RIVER MAY ACTUALLY SEE SOME SUN LATER THIS AFTERNOON
AS A DRY POCKET OF AIR FILTERS IN BEFORE CLOUDING OVER AGAIN THIS
EVENING.
FORECAST IS ON TRACK AT UPDATE TIME.
UNGER
&&
.AVIATION...
12Z TAF DISCUSSION.
RA/+RA ALREADY AFFECTING CKV/BNA THIS MORNING AND WILL REACH CSV
BY 15Z...WITH RAIN ENDING AT CKV AROUND 17Z...BNA 19Z...AND CSV
23Z PER HRRR MODEL. GUSTY SE WINDS OVER 30KTS AT TIMES TO CONTINUE
AT BNA UNTIL 13Z...AND 17Z AT CSV...UNTIL WSHIFT PASSES AND WINDS
SUBSIDE SIGNIFICANTLY. VFR/MVFR CIGS/VIS GENERALLY EXPECTED WITH
TEMPO IFR POSSIBLE ESPECIALLY AT CSV.
SHAMBURGER
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON CST TODAY ALL OF MIDDLE TENNESSEE.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
620 AM CST WED NOV 18 2015
.12Z AVIATION UPDATE...
RA/+RA ALREADY AFFECTING CKV/BNA THIS MORNING AND WILL REACH CSV
BY 15Z...WITH RAIN ENDING AT CKV AROUND 17Z...BNA 19Z...AND CSV
23Z PER HRRR MODEL. GUSTY SE WINDS OVER 30KTS AT TIMES TO
CONTINUE AT BNA UNTIL 13Z...AND 17Z AT CSV...UNTIL WSHIFT PASSES
AND WINDS SUBSIDE SIGNIFICANTLY. VFR/MVFR CIGS/VIS GENERALLY
EXPECTED WITH TEMPO IFR POSSIBLE ESPECIALLY AT CSV.
SHAMBURGER
&&
.PREV DISCUSSION...
DISCUSSION...
COMPLEX SETUP SYNOPTICALLY FROM PLAINS INTO SOUTHEASTERN U.S.
989 MBAR SURFACE LOW CENTERED OVER IOWA THIS MORNING WITH
OCCLUDED FRONT DOWN THROUGH FAR EASTERN MISSOURI THEN DRAPED DOWN
THROUGH MEMPHIS AREA INTO EASTERN LOUISIANA. WARM FRONT FROM
ABOUT DYERSBURG TO TALLAHASSEE. PRIMARY AIR MASS CHANGE (PACIFIC
AIR MASS) STILL BACK BEHIND COLD FRONT IN EASTERN OKLAHOMA.
LATEST RADARS SHOWING RATHER BROAD SOLID AREA OF SHOWERS WITH AN
EMBEDDED SKINNY LINE OF STRONGER SHOWERS WITH ISOLATED THUNDER
EXTENDING FROM FAR WESTERN KENTUCKY SOUTHWARD ALONG TENNESSEE
RIVER INTO EASTERN MISSISSIPPI. THIS ACTIVITY BEEN WORKING
STEADILY BUT SLOWLY EASTWARD AND WILL EVENTUALLY WORKS IT WAY
INTO WESTERN MIDDLE TENNESSEE THIS MORNING AND TRANSLATE ACROSS
THE MID STATE DURING THE DAY. EVEN THOUGH THERE IS PLENTY OF
HYDRODYNAMICS (STRONG WIND FIELDS) ACROSS OUR AREA WITH 75 KNOT
LOW LEVEL JET THERE IS A LACK OF THERMODYNAMIC INSTABILITY (LOW
CAPE). SO NOT EXPECTING ANY SEVERE STORMS BUT SURFACE PRESSURE
GRADIENT IS TIGHER THAN DICKS HAT BAND SO LOOK FOR WIND GUSTS ON
THE ORDER OF 40 MPH AT TIMES ACROSS THE MID STATE...WHICH WILL
BLOW LIDS OFF TRASH CANS AND BREAK A FEW LIMBS. BY THIS EVENING
SYSTEM WILL BE PULLING AWAY FROM AREA TAKING THE RAIN WITH IT BUT
PLATEAU LIKELY TO HAVE SHOWERS THROUGH ABOUT 9 PM CST. SKIES WILL
CLEAR FROM THE WEST THIS EVENING AS SURFACE PACIFIC HIGH BUILDS
INTO THE REGION WITH LOWS TONIGHT DOWN IN THE 40S AND HIGHS ON
THURSDAY IN THE LOWER 60S. LOWS THURSDAY NIGHT DOWN IN THE 30S AND
THERE COULD BE A FEW SPOTS WITH FREEZING TEMPS ESPECIALLY MIDDLE
TENNESSEE AS HIGH PRESSURE...LIGHT WIND FIELD AND CLEAR SKIES
SETTLE OVER THE AREA. A FAST MOVING COLD FRONT APPROACHES THIS
WEEKEND BRINGING A CHANCE FOR SHOWERS ON SATURDAY FOLLOWED BY
COOLER TEMPS AS THIS WILL BE CONTINETAL POLAR AIR...COLDEST OF
THE SEASON SO FAR WITH LOWS SATURDAY NIGHT DOWN IN THE 20S WITH
HIGHS ON SUNDAY IN THE LOW TO MIDDLE 40S. ANOTHER CHILLY NIGHT
SUNDAY NIGHT WITH TEMPS GRADUALLY WARMING AS WE INTO THE MIDDLE OF
NEXT WEEK. I KEPT IT DRY SUNDAY THROUGH WEDNESDAY OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 67 46 62 36 / 100 10 0 10
CLARKSVILLE 64 44 61 34 / 100 10 0 10
CROSSVILLE 68 46 61 35 / 100 40 0 10
COLUMBIA 66 42 63 33 / 100 10 0 10
LAWRENCEBURG 66 43 63 36 / 100 10 0 10
WAVERLY 61 46 62 37 / 100 10 0 10
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL NOON CST TODAY FOR TNZ005>011-023>034-
056>066-075-077>080-093>095.
&&
$$
55
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1152 AM CST WED NOV 18 2015
.AVIATION...
VFR CONDITIONS WILL CONTINUE AT ALL TERMINALS FOR THE NEXT 24
HOURS. BREEZY W-SW SURFACE WINDS WILL RELAX QUICKLY THIS
EVENING...THEN TURN TO THE NORTH AROUND 05-06 UTC AS A MODEST
COLD FRONT MOVES THROUGH.
&&
.PREV DISCUSSION... /ISSUED 520 AM CST WED NOV 18 2015/
AVIATION...
DRY VFR. WEST-NORTHWEST FLOW ALOFT. SURFACE TROUGH GRADUALLY
DEEPENING TODAY LEADING TO BREEZY CONDITIONS FOLLOWED BY A
WEAKENING COLD FRONT LATER TONIGHT. SEVERAL CHANGE GROUPS FOR
TAFS RELATED TO WIND CHANGES. RMCQUEEN
PREV DISCUSSION... /ISSUED 409 AM CST WED NOV 18 2015/
SHORT TERM...
UPPER LEVEL HEIGHT FIELDS WERE UNWINDING THIS MORNING JUST BEHIND
THE UPPER LOW SPINNING THROUGH EASTERN KANSAS...WHICH IS EXPECTED TO
OPEN WHILE LIFTING INTO THE WESTERN GREAT LAKES. DEEP SUBSIDENCE AND
DRYING WILL DOMINATE. LATER TODAY...THE NEXT DISTURBANCE WILL CURL
OUT OF THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS WITH SLIGHTLY
BACKED FLOW LEADING TO SURFACE TROUGHING. RESULT WILL BE MODESTLY
BREEZY WEST WINDS AND WARMER TEMPERATURES THIS AFTERNOON. SOLUTIONS
FAVOR SOUTHERN ZONES FOR BEST OF THESE LOW-END BREEZES...SUSTAINED
15 TO 20 KNOTS OR SO. STARTING OUT FAIRLY COOL THIS MORNING...BUT
WITH THE ENHANCED DOWNSLOPE FLOW TEMPERATURES BY LATER TODAY SHOULD
END UP NEAR OR NOTCH ABOVE MID-NOVEMBER NORMALS. ALSO GAVE LEAN
TOWARD RECENT RAP DEWPOINT SOLUTIONS SHOWING MORE SURFACE DRYING
SOUTHERN AREAS...MAKES SENSE THIS PATTERN.
BY THIS EVENING THE SURFACE TROUGH SHOULD DRIFT OVER THE AREA WITH
LOOSENING SURFACE PRESSURE GRADIENT...AND STILL SOMEWHAT MILD
TEMPERATURES. A COLD FRONT FLUNG SOUTHWARD FROM THE NORTHERN PLAINS
SYSTEM...WILL EDGE THROUGH THE AREA NEAR OR JUST AFTER MIDNIGHT.
SURFACE WINDS ALSO ON THE LOW END OF BREEZY BEHIND THIS WEAKENING
COLD FRONT. RMCQUEEN
LONG TERM...
BREEZY NORTHEAST WINDS WILL REMAIN IN PLACE THURSDAY MORNING
BEHIND THE FIRST OF A PAIR OF FRONTS TO MOVE THROUGH THE SOUTH
PLAINS REGION COURTESY OF A COUPLE OF NORTHERN STREAM DISTURBANCES
MOVING ACROSS LOWER CANADA INTO THE GREAT PLAINS. A SUBTLE SHOT OF
COOLER AIR BEHIND THIS INITIAL SYSTEM WILL KNOCK HIGHS DOWN INTO
THE MID-UPPER 50S FOR THE MOST PART THURSDAY BEFORE RENEWED
SURFACE TROUGHING IN THE FRONT RANGE VEERS WINDS SOUTHWESTERLY FOR
FRIDAY. THIS WILL PUSH TEMPERATURES BACK INTO THE 60S BEFORE A
MUCH STRONGER FRONT ENTERS THE EXTREME SOUTHERN PANHANDLE BY EARLY
FRIDAY EVENING. A TIGHTENING PRESSURE GRADIENT AHEAD OF A 1035 MB
SURFACE RIDGE WILL INCREASE NORTHERLY WINDS TO ON THE ORDER OF
20-25 MPH DURING THE EVENING AND OVERNIGHT HOURS BEFORE GRADUALLY
DIMINISHING THROUGH THE DAY. HOWEVER...THE COLDEST AIRMASS OF THE
FALL SEASON WILL BE ENTRENCHED ACROSS THE REGION TO BEGIN THE
WEEKEND WITH HIGHS ON SATURDAY ONLY MAKING IT INTO THE 40S.
AFOREMENTIONED SURFACE RIDGE WILL SLIDE SOUTH SATURDAY NIGHT IN
VICINITY OF THE SOUTH PLAINS AND ROLLING PLAINS...PERHAPS VEERING
WINDS SOUTHERLY OVERNIGHT. DESPITE SOME POSSIBLE WEAK WARM AIR
ADVECTION...THE MAGNITUDE OF THE MODIFIED-ARCTIC AIRMASS SHOULD
ALLOW FOR A HARD FREEZE WITH LOWS BOTTOMING OUT IN THE LOW-MID 20S
ON MUCH OF THE CAPROCK WHILE LOCALES IN THE ROLLING PLAINS REMAIN
IN THE MID-UPPER 20S SUNDAY MORNING.
WILL THEN KEEP AN EYE ON YET ANOTHER DISTURBANCE PROPAGATING THROUGH
THE LONG-LIVED NORTHWESTERLY FLOW REGIME BEFORE BACKING FLOW ALOFT
TAKES PLACE EARLY NEXT WEEK DOWNSTREAM OF CYCLONIC FLOW ACROSS THE
PACIFIC COAST. SUBTROPICAL JET POSSIBLY COUPLED WITH THE POLAR JET
BY MID WEEK WILL MOVE OVERHEAD ATTEMPTING TO ENHANCE MID-UPPER
MOISTURE. HOWEVER...TIMING OF LOW LEVEL MOISTURE RETURN BEHIND
FRIDAY EVENING/SATURDAYS FRONT WILL BE THE DRIVER AS TO WHEN
PRECIPITATION CHANCES TAKE A HOLD LOCALLY. SOME INDICATIONS OF
ENOUGH OF THIS BY TUESDAY...BUT WILL WAIT UNTIL TUESDAY NIGHT TO
INTRODUCE POPS GIVEN STRENGTH OF THE EARLY WEEKEND FRONT. THESE
CHANCES LOOK TO CONTINUE INTO MID WEEK AT THIS POINT...BUT WILL
CERTAINLY HAVE TO MONITOR HOW THE WESTERN CONUS SYSTEM DEVELOPS
ALONG WITH DEGREE OF LOW LEVEL MOISTURE RETURN. NONETHELESS...HIGH
TEMPERATURES SHOULD REBOUND INTO THE 60S DURING THE WEEK WITH LOWS
IN THE 30S/40S.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
33
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
520 AM CST WED NOV 18 2015
.AVIATION...
DRY VFR. WEST-NORTHWEST FLOW ALOFT. SURFACE TROUGH GRADUALLY
DEEPENING TODAY LEADING TO BREEZY CONDITIONS FOLLOWED BY A
WEAKENING COLD FRONT LATER TONIGHT. SEVERAL CHANGE GROUPS FOR
TAFS RELATED TO WIND CHANGES. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 409 AM CST WED NOV 18 2015/
SHORT TERM...
UPPER LEVEL HEIGHT FIELDS WERE UNWINDING THIS MORNING JUST BEHIND
THE UPPER LOW SPINNING THROUGH EASTERN KANSAS...WHICH IS EXPECTED TO
OPEN WHILE LIFTING INTO THE WESTERN GREAT LAKES. DEEP SUBSIDENCE AND
DRYING WILL DOMINATE. LATER TODAY...THE NEXT DISTURBANCE WILL CURL
OUT OF THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS WITH SLIGHTLY
BACKED FLOW LEADING TO SURFACE TROUGHING. RESULT WILL BE MODESTLY
BREEZY WEST WINDS AND WARMER TEMPERATURES THIS AFTERNOON. SOLUTIONS
FAVOR SOUTHERN ZONES FOR BEST OF THESE LOW-END BREEZES...SUSTAINED
15 TO 20 KNOTS OR SO. STARTING OUT FAIRLY COOL THIS MORNING...BUT
WITH THE ENHANCED DOWNSLOPE FLOW TEMPERATURES BY LATER TODAY SHOULD
END UP NEAR OR NOTCH ABOVE MID-NOVEMBER NORMALS. ALSO GAVE LEAN
TOWARD RECENT RAP DEWPOINT SOLUTIONS SHOWING MORE SURFACE DRYING
SOUTHERN AREAS...MAKES SENSE THIS PATTERN.
BY THIS EVENING THE SURFACE TROUGH SHOULD DRIFT OVER THE AREA WITH
LOOSENING SURFACE PRESSURE GRADIENT...AND STILL SOMEWHAT MILD
TEMPERATURES. A COLD FRONT FLUNG SOUTHWARD FROM THE NORTHERN PLAINS
SYSTEM...WILL EDGE THROUGH THE AREA NEAR OR JUST AFTER MIDNIGHT.
SURFACE WINDS ALSO ON THE LOW END OF BREEZY BEHIND THIS WEAKENING
COLD FRONT. RMCQUEEN
LONG TERM...
BREEZY NORTHEAST WINDS WILL REMAIN IN PLACE THURSDAY MORNING
BEHIND THE FIRST OF A PAIR OF FRONTS TO MOVE THROUGH THE SOUTH
PLAINS REGION COURTESY OF A COUPLE OF NORTHERN STREAM DISTURBANCES
MOVING ACROSS LOWER CANADA INTO THE GREAT PLAINS. A SUBTLE SHOT OF
COOLER AIR BEHIND THIS INITIAL SYSTEM WILL KNOCK HIGHS DOWN INTO
THE MID-UPPER 50S FOR THE MOST PART THURSDAY BEFORE RENEWED
SURFACE TROUGHING IN THE FRONT RANGE VEERS WINDS SOUTHWESTERLY FOR
FRIDAY. THIS WILL PUSH TEMPERATURES BACK INTO THE 60S BEFORE A
MUCH STRONGER FRONT ENTERS THE EXTREME SOUTHERN PANHANDLE BY EARLY
FRIDAY EVENING. A TIGHTENING PRESSURE GRADIENT AHEAD OF A 1035 MB
SURFACE RIDGE WILL INCREASE NORTHERLY WINDS TO ON THE ORDER OF
20-25 MPH DURING THE EVENING AND OVERNIGHT HOURS BEFORE GRADUALLY
DIMINISHING THROUGH THE DAY. HOWEVER...THE COLDEST AIRMASS OF THE
FALL SEASON WILL BE ENTRENCHED ACROSS THE REGION TO BEGIN THE
WEEKEND WITH HIGHS ON SATURDAY ONLY MAKING IT INTO THE 40S.
AFOREMENTIONED SURFACE RIDGE WILL SLIDE SOUTH SATURDAY NIGHT IN
VICINITY OF THE SOUTH PLAINS AND ROLLING PLAINS...PERHAPS VEERING
WINDS SOUTHERLY OVERNIGHT. DESPITE SOME POSSIBLE WEAK WARM AIR
ADVECTION...THE MAGNITUDE OF THE MODIFIED-ARCTIC AIRMASS SHOULD
ALLOW FOR A HARD FREEZE WITH LOWS BOTTOMING OUT IN THE LOW-MID 20S
ON MUCH OF THE CAPROCK WHILE LOCALES IN THE ROLLING PLAINS REMAIN
IN THE MID-UPPER 20S SUNDAY MORNING.
WILL THEN KEEP AN EYE ON YET ANOTHER DISTURBANCE PROPAGATING THROUGH
THE LONG-LIVED NORTHWESTERLY FLOW REGIME BEFORE BACKING FLOW ALOFT
TAKES PLACE EARLY NEXT WEEK DOWNSTREAM OF CYCLONIC FLOW ACROSS THE
PACIFIC COAST. SUBTROPICAL JET POSSIBLY COUPLED WITH THE POLAR JET
BY MID WEEK WILL MOVE OVERHEAD ATTEMPTING TO ENHANCE MID-UPPER
MOISTURE. HOWEVER...TIMING OF LOW LEVEL MOISTURE RETURN BEHIND
FRIDAY EVENING/SATURDAYS FRONT WILL BE THE DRIVER AS TO WHEN
PRECIPITATION CHANCES TAKE A HOLD LOCALLY. SOME INDICATIONS OF
ENOUGH OF THIS BY TUESDAY...BUT WILL WAIT UNTIL TUESDAY NIGHT TO
INTRODUCE POPS GIVEN STRENGTH OF THE EARLY WEEKEND FRONT. THESE
CHANCES LOOK TO CONTINUE INTO MID WEEK AT THIS POINT...BUT WILL
CERTAINLY HAVE TO MONITOR HOW THE WESTERN CONUS SYSTEM DEVELOPS
ALONG WITH DEGREE OF LOW LEVEL MOISTURE RETURN. NONETHELESS...HIGH
TEMPERATURES SHOULD REBOUND INTO THE 60S DURING THE WEEK WITH LOWS
IN THE 30S/40S.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
409 AM CST WED NOV 18 2015
.SHORT TERM...
UPPER LEVEL HEIGHT FIELDS WERE UNWINDING THIS MORNING JUST BEHIND
THE UPPER LOW SPINNING THROUGH EASTERN KANSAS...WHICH IS EXPECTED TO
OPEN WHILE LIFTING INTO THE WESTERN GREAT LAKES. DEEP SUBSIDENCE AND
DRYING WILL DOMINATE. LATER TODAY...THE NEXT DISTURBANCE WILL CURL
OUT OF THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS WITH SLIGHTLY
BACKED FLOW LEADING TO SURFACE TROUGHING. RESULT WILL BE MODESTLY
BREEZY WEST WINDS AND WARMER TEMPERATURES THIS AFTERNOON. SOLUTIONS
FAVOR SOUTHERN ZONES FOR BEST OF THESE LOW-END BREEZES...SUSTAINED
15 TO 20 KNOTS OR SO. STARTING OUT FAIRLY COOL THIS MORNING...BUT
WITH THE ENHANCED DOWNSLOPE FLOW TEMPERATURES BY LATER TODAY SHOULD
END UP NEAR OR NOTCH ABOVE MID-NOVEMBER NORMALS. ALSO GAVE LEAN
TOWARD RECENT RAP DEWPOINT SOLUTIONS SHOWING MORE SURFACE DRYING
SOUTHERN AREAS...MAKES SENSE THIS PATTERN.
BY THIS EVENING THE SURFACE TROUGH SHOULD DRIFT OVER THE AREA WITH
LOOSENING SURFACE PRESSURE GRADIENT...AND STILL SOMEWHAT MILD
TEMPERATURES. A COLD FRONT FLUNG SOUTHWARD FROM THE NORTHERN PLAINS
SYSTEM...WILL EDGE THROUGH THE AREA NEAR OR JUST AFTER MIDNIGHT.
SURFACE WINDS ALSO ON THE LOW END OF BREEZY BEHIND THIS WEAKENING
COLD FRONT. RMCQUEEN
.LONG TERM...
BREEZY NORTHEAST WINDS WILL REMAIN IN PLACE THURSDAY MORNING
BEHIND THE FIRST OF A PAIR OF FRONTS TO MOVE THROUGH THE SOUTH
PLAINS REGION COURTESY OF A COUPLE OF NORTHERN STREAM DISTURBANCES
MOVING ACROSS LOWER CANADA INTO THE GREAT PLAINS. A SUBTLE SHOT OF
COOLER AIR BEHIND THIS INITIAL SYSTEM WILL KNOCK HIGHS DOWN INTO
THE MID-UPPER 50S FOR THE MOST PART THURSDAY BEFORE RENEWED
SURFACE TROUGHING IN THE FRONT RANGE VEERS WINDS SOUTHWESTERLY FOR
FRIDAY. THIS WILL PUSH TEMPERATURES BACK INTO THE 60S BEFORE A
MUCH STRONGER FRONT ENTERS THE EXTREME SOUTHERN PANHANDLE BY EARLY
FRIDAY EVENING. A TIGHTENING PRESSURE GRADIENT AHEAD OF A 1035 MB
SURFACE RIDGE WILL INCREASE NORTHERLY WINDS TO ON THE ORDER OF
20-25 MPH DURING THE EVENING AND OVERNIGHT HOURS BEFORE GRADUALLY
DIMINISHING THROUGH THE DAY. HOWEVER...THE COLDEST AIRMASS OF THE
FALL SEASON WILL BE ENTRENCHED ACROSS THE REGION TO BEGIN THE
WEEKEND WITH HIGHS ON SATURDAY ONLY MAKING IT INTO THE 40S.
AFOREMENTIONED SURFACE RIDGE WILL SLIDE SOUTH SATURDAY NIGHT IN
VICINITY OF THE SOUTH PLAINS AND ROLLING PLAINS...PERHAPS VEERING
WINDS SOUTHERLY OVERNIGHT. DESPITE SOME POSSIBLE WEAK WARM AIR
ADVECTION...THE MAGNITUDE OF THE MODIFIED-ARCTIC AIRMASS SHOULD
ALLOW FOR A HARD FREEZE WITH LOWS BOTTOMING OUT IN THE LOW-MID 20S
ON MUCH OF THE CAPROCK WHILE LOCALES IN THE ROLLING PLAINS REMAIN
IN THE MID-UPPER 20S SUNDAY MORNING.
WILL THEN KEEP AN EYE ON YET ANOTHER DISTURBANCE PROPAGATING THROUGH
THE LONG-LIVED NORTHWESTERLY FLOW REGIME BEFORE BACKING FLOW ALOFT
TAKES PLACE EARLY NEXT WEEK DOWNSTREAM OF CYCLONIC FLOW ACROSS THE
PACIFIC COAST. SUBTROPICAL JET POSSIBLY COUPLED WITH THE POLAR JET
BY MID WEEK WILL MOVE OVERHEAD ATTEMPTING TO ENHANCE MID-UPPER
MOISTURE. HOWEVER...TIMING OF LOW LEVEL MOISTURE RETURN BEHIND
FRIDAY EVENING/SATURDAYS FRONT WILL BE THE DRIVER AS TO WHEN
PRECIPITATION CHANCES TAKE A HOLD LOCALLY. SOME INDICATIONS OF
ENOUGH OF THIS BY TUESDAY...BUT WILL WAIT UNTIL TUESDAY NIGHT TO
INTRODUCE POPS GIVEN STRENGTH OF THE EARLY WEEKEND FRONT. THESE
CHANCES LOOK TO CONTINUE INTO MID WEEK AT THIS POINT...BUT WILL
CERTAINLY HAVE TO MONITOR HOW THE WESTERN CONUS SYSTEM DEVELOPS
ALONG WITH DEGREE OF LOW LEVEL MOISTURE RETURN. NONETHELESS...HIGH
TEMPERATURES SHOULD REBOUND INTO THE 60S DURING THE WEEK WITH LOWS
IN THE 30S/40S.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/31
AREA FORECAST DISCUSSION
NWS MIAMI FL
114 AM EST FRI NOV 20 2015
.AVIATION...
FEW SHOWERS IN VICINITY OF KPBI EARLY THIS MORNING...BUT EXPECTED
SCATTERED ACTIVITY TO IMPACT ALL TERMINALS BY SUNRISE...WITH
SHOWER CHANCES HIGH ENOUGH TO WARRANT VCSH THROUG THE PERIOD.
OVERALL VFR CONDITIONS PREVAIL...BUT SOME MVFR CIGS/VSBY PSBL AT
TIMES. GENERAL NE WIND AOB 10 KT FRIDAY.
&&
.PREV DISCUSSION... /ISSUED 803 PM EST THU NOV 19 2015/
UPDATE...
MINOR UPDATE TO THE GRIDS THIS EVENING, MAINLY TO ADJUST POPS FOR
CURRENT CONDITIONS. THE HRRR IS INDICATING THAT THE EAST COAST MAY
SEE LESS SHOWERS OVERNIGHT THAN PREVIOUSLY THOUGHT. HOWEVER, MOST
POPS WERE ONLY SLIGHT CHANCE TO CHANCE ANYWAYS, AND GIVEN
CONTINUED UNCERTAINTY LATER TONIGHT, HAVE LEFT FORECAST RIDE.
OTHERWISE, THE FORECAST IS PRETTY MUCH ON TRACK THIS EVENING.
PREV DISCUSSION... /ISSUED 432 PM EST THU NOV 19 2015/
DISCUSSION...
THE MAIN STORY FOR TODAY IS THE APPROACHING COLD FRONT. IT HAS
PUSHED HIGH PRESSURE TO THE EAST, BRINGING A MORE SOUTH TO
SOUTHEASTERLY FLOW TO SOUTH FLORIDA. MOISTURE HAS REMAINED OVER
THE AREA, AND SHOWERS HAVE BEEN THE RESULT. SOME ISOLATED
THUNDERSTORMS WILL ALSO BE POSSIBLE THIS EVENING.
THE FRONT WILL MOVE INTO CENTRAL FLORIDA AND SLOWLY APPROACH THE
CWA TONIGHT. BY MID-DAY TOMORROW, THE FRONT WILL STALL, PROBABLY
JUST NORTH OF THE LAKE. THIS WILL KEEP MOISTURE AND INSTABILITY
OVER SOUTH FLORIDA THROUGH THE WEEKEND. THERE DOES LOOK TO BE
ABUNDANT CLOUD COVER ASSOCIATED WITH THE FRONT. THIS WILL POSSIBLY
SOMEWHAT HINDER CONVECTIVE DEVELOPMENT WHILE THE FRONT IS AROUND.
BUT, THIS MAY ONLY KEEP MOST CONVECTION FROM DEVELOPING INTO
THUNDERSTORMS. PWATS THROUGH AT LEAST SATURDAY WILL BE AROUND 2
INCHES. THERE WILL ALSO BE A JET STREAK MOVING OVER CENTRAL
FLORIDA BY LATE TOMORROW. THIS COULD HELP GENERATE SOME HEAVY RAIN
OVERNIGHT FRIDAY INTO SATURDAY. THERE IS, OF COURSE, UNCERTAINTY
WITH TIMING AND LOCATION OF THE JET, AND ANY SMALL CHANGE WILL
CHANGE THIS. STILL HAVE SCATTERED SHOWERS FOR MOST OF THE WEEKEND,
ALONG WITH A SLIGHT CHANCE OF THUNDERSTORMS.
BY SATURDAY EVENING, ANOTHER JET MAY MOVE INTO THE AREA. THE GFS
KEEP IT FURTHER NORTH, BUT THE ECMWF BRINGS IT CLOSE ENOUGH THAT
IT BRINGS ADDITIONAL CHANCES OF HEAVY RAIN. LOOKING AT THE 5 DAY
PRECIP TOTAL FROM WPC, THE HEAVIEST ACCUMULATIONS WILL BE WELL OFF
SHORE OF THE TREASURE COAST. BUT, THEY STILL HAVE 2 INCHES OVER
PORTIONS OF THE CWA OVER THE NEXT 5 DAYS. THE 24 HOUR TOTALS ARE
GENERALLY BETWEEN A HALF INCH AND ONE INCH. SO, HAVE KEPT THINGS
JUST AS TYPICAL SCATTERED SHOWERS FOR NOW.
THE FRONT WILL BEGIN TO PUSH THROUGH ON SUNDAY. THIS WILL HAVE THE
POTENTIAL TO BE THE BUSIEST WEATHER DAY, AS THE FRONT WILL BE
FAIRLY STRONG. THE PWATS WILL GO FROM AROUND 2 INCHES AHEAD OF IT
DOWN TO AROUND THREE QUARTERS OF AN INCH BEHIND IT. THE MODELS ARE
INDICATING THE FRONT SHOULD BE THROUGH THE CWA IN THE MIDDLE OF
THE NIGHT, SUNDAY NIGHT. THE WIND SLOWLY PICKS UP, GENERALLY
BEHIND THE FRONT. THE BIGGEST QUESTION IS HOW WILL THE CLOUD COVER
AFFECT THE CONVECTION ASSOCIATED WITH THE FRONT. CURRENTLY, WENT
WITH LIKELY POPS SUNDAY. LIKELY SOME SCATTERED SHOWERS AHEAD OF
THE FRONT, AND A LINE OF SHOWERS, POSSIBLY THUNDERSTORMS, ALONG
THE FRONT.
BEHIND THE FRONT, A COOLER, DRIER AIR MASS SETTLES IN. FORECAST
HIGHS MONDAY ARE IN THE LOW TO MID 70S, WITH DEW POINTS IN THE 50S
AND 60S. BY TUESDAY MORNING, THE FORECAST LOWS ARE ARE IN THE MID
50S TO LOW 60S ACROSS SOUTH FLORIDA, WITH THE COLDER TEMPS WEST OF
THE LAKE. AS HIGH PRESSURE SETTLES IN TO THE NORTH, BEHIND THE
FRONT, WE WILL SEE AN EASTERLY FLOW RETURN, AS WELL AS A GRADUAL
WARM UP BY THE END OF THE WEEK.
MARINE...
A COLD FRONT WILL STALL JUST TO THE NORTH OF THE AREA BY TOMORROW.
THIS WILL BRING CONTINUED UNSETTLED WEATHER TO ALL SOUTH FLORIDA
WATERS OVER THE WEEKEND. THE FRONT WILL PUSH THROUGH THE AREA
SUNDAY NIGHT. THIS WILL BRING A SIGNIFICANT INCREASE IN WINDS AND
WILL LIKELY CAUSE HAZARDOUS MARINE CONDITIONS FOR ALL SOUTH
FLORIDA WATERS BY MONDAY, AS WELL AS BRING THE RETURN OF A HIGH
RISK OF RIP CURRENTS TO THE ATLANTIC BEACHES BY MONDAY, FOR A GOOD
PART OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 74 82 71 84 / 50 70 70 70
FORT LAUDERDALE 73 82 72 85 / 50 70 70 70
MIAMI 73 83 73 84 / 50 60 70 60
NAPLES 71 82 72 81 / 40 60 70 60
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...60/BD
LONG TERM....60/BD
AVIATION...23/SK
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
328 AM CST FRI NOV 20 2015
.SYNOPSIS...
ISSUED AT 328 AM CST FRI NOV 20 2015
CURRENT SATELLITE IMAGERY DEPICTS CLEAR SKIES TONIGHT AS HIGH
PRESSURE IS IN PLACE ACROSS THE REGION. AT THE SFC...DRY AIR IS IN
PLACE WITH DEWPOINTS IN THE LOW 20S TO UPPER TEENS. OVER THE FAR
NORTHERN CONUS ROCKY MOUNTAINS...AN UPPER LEVEL WAVE WAS MOVING SE
INTO THE HIGH PLAINS. THIS WAVE IS EXPECTED TO BRING OUR FIRST
WINTER STORM TO THE AREA LATER TODAY AND OVERNIGHT AND INTO SATURDAY
MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 328 AM CST FRI NOV 20 2015
MAIN FORECAST CONCERN FOR THE SHORT TERM IS THE IMPENDING WINTER
STORM TO AFFECT THE AREA TODAY AND TONIGHT. OVERALL FORECAST HAS
CHANGED LITTLE WITH THE MOST NOTABLE CHANGE WITH A SHIFT SOUTH OF
THE HEAVY SNOW AXIS. GUIDANCE SUGGESTS THAT PRECIP COULD START AS
EARLY AS 18Z ACROSS THE FAR NORTHERN ZONES. OVERALL NO CHANGES TO
THE CURRENT HEADLINES WERE MADE.
H5 WAVE IS FORECAST TO MOVE INTO THE CENTRAL PLAINS BY 18Z TODAY.
MODELS ARE CONSISTENT WITH THE PLACEMENT OF THE MAIN FORCING. THE
GFS IS THE FASTEST OF THE OPERATIONAL MODELS AND THIS SEEMS TO BE
SLIGHTLY SLOWER THAN THE GEFS ENSEMBLE MEAN. BETWEEN 00Z AND 12Z
SATURDAY A H3 JET IS EXPECTED TO PASS TO OUR SOUTH WITH THE
FAVORABLE LEFT EXIT REGION OVER OUR AREA. THIS WILL HELP TO
INCREASE VERTICAL MOTION FROM 00Z TO 12Z SATURDAY. THE H85 LOW
CENTER IS FORECAST TO MOVE JUST TO OUR SOUTH THROUGH THE PERIOD
WITH THE MAJORITY OF THE CWA IN THE BELOW FREEZING SIDE.
MODEL SOUNDINGS ARE INDICATIVE OF SNOW AS SOON AS EVAPORATIVE
COOLING RAPIDLY COOLS THE LOW LEVELS. ONSET OF PRECIP LOOKS TO BE
RAIN AT FIRST...QUICKLY CHANGING TO RASN AND THEN OVER TO ALL SN
SHORTLY AFTER THIS.
TIMING...HIRES GUIDANCE IS HINTING AT A BAND OF PRECIP ACROSS FAR
NORTHERN ZONES AS EARLY AS 18Z. THIS BAND MAY BE LIGHT AT FIRST
AND MAY TAKE SOME TIME TO COOL/MOISTEN UP THE BL BEFORE PRECIP
STARTS TO FALL. THE REST OF THE AREA WILL SEE THE PRECIP START
FROM WEST TO EAST. THE BEST CHANCE FOR ONSET IN THE WEST WILL BE
BETWEEN 20Z AND 22Z. MULTIPLE HRRR RUNS ARE CONSISTENT IN THIS
TIMING. THE HRRR AND OTHER CAMS SUGGEST A 23Z TO 01Z START TIME
FOR THE AREAS ALONG THE MISSISSIPPI RIVER. AREAS ACROSS IL COULD
SEE PRECIP START AS SOON AS 00Z...BUT LIKELY 01Z TO 02Z.
SNOWFALL TOTALS HAVE NOT CHANGED ALL THE MUCH. WITH THE LATEST
GUIDANCE AND TRENDS FROM DPROG DT...IT APPEARS THAT THE HEAVIEST
SNOW HAS SHIFTED SOUTH SOME 40 MILES. THIS PUTS A ROCKFORD TO
CLINTON TO IOWA CITY LINE AS OUR CURRENT BEST GUESS FOR THE
HEAVIEST SNOW AXIS. TOTALS OF UP TO TEN INCHES OR MORE COULD BE
POSSIBLE ALONG THE AXIS.
SOME CONCERNS ABOUT THE FORECAST ARE THE WARM GROUND TEMPS AND THE
EFFECTS OF EVAPORATIVE COOLING. WHILE THE QPF AND SNOW RATIOS
SUPPORT THIS MUCH SNOW...THERE IS A POSSIBILITY THAT THE WARM
GROUND WILL MELT SNOW AND LEAD TO LESS ACCUMULATION THAN FORECAST.
THIS NEEDS TO BE KEPT IN MIND. REGARDLESS OF THE ACTUAL
TOTALS...IMPACTS FROM THIS STORM WILL LIKELY CAUSE DRIVING ISSUES
AS THE SNOW RATE MAY MAKE IT DIFFICULT TO KEEP ROADS CLEARED
...ESPECIALLY LATER AT NIGHT AND IN THE HEAVIER BANDS. THERE ARE
SOME CONCERNS ABOUT ICE FORMING ON UNTREATED ROADWAYS SO BE SURE
TO DRIVE CAUTIOUSLY IF YOU MUST BE OUT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 328 AM CST FRI NOV 20 2015
INITIAL FOCUS IS ON THE EXITING WINTER STORM SATURDAY MORNING...
WHICH WILL BE FOLLOWED BY BITTER COLD TEMPERATURES THROUGH SUNDAY. A
RETURN TO A MORE ZONAL UPPER LEVEL FLOW NEXT WEEK WILL RESULT IN
TEMPERATURES RECOVERING BACK TO NEAR NORMAL WITH INCREASING RAIN
CHANCES IN THE LATTER HALF OF THE WEEK AS GULF MOISTURE RETURNS.
MODEL CONSENSUS HAS THE SURFACE LOW OVER W CENTRAL IL AT 12Z
DEEPENING AND EJECTING NORTHEAST INTO THE GREAT LAKES WITH THE
PASSAGE OF THE UPPER LEVEL VORT MAX FOLLOWED BY ISENTROPIC DOWNGLIDE
AND BRISK WINDS BEHIND THE SYSTEM. THE TIMING OF THE BACK EDGE OF
THE SYSTEM AND THE PASSING DEFORMATION AXIS NW OF THE SURFACE AND
850 MB LOWS HAS BEEN FAIRLY CONSISTENT OVER THE PAST SEVERAL MODEL
RUNS. THIS SUGGESTS ADDITIONAL 1 TO 2 INCH ACCUMULATIONS WILL BE
POSSIBLE PRIMARILY OVER NW IL...WITH TRACE TO QUARTER INCH AMOUNTS
FURTHER WEST AND SOUTH. HOWEVER...EVEN WITHOUT SIGNIFICANT
SNOW...BRISK N-NW WINDS OF 15 TO 25 MPH...POSSIBLY INTO THE 30 MPH
RANGE...MAY CAUSE SOME DRIFTING SNOW ACROSS THE WEST THROUGH THE
MORNING AND WILL KEEP THE CURRENT 18Z EXPIRATION TIME OF THE
HEADLINES GOING FOR NOW. STRONG COLD AIR ADVECTION AND FRESH
SNOWFALL WILL LEAD TO A WINTER-LIKE DAY WITH TEMPERATURES STEADY TO
FALLING THROUGH THE MID TO UPPER 20S EVEN AS THE DEVELOPING LOW
LEVEL ANTICYCLONIC FLOW LEADS TO BREAKS OF SUNSHINE BY AFTERNOON.
SATURDAY NIGHT AND SUNDAY...LIGHTER SURFACE WINDS WITH THE PASSAGE
OF RIDGE AXIS WILL ALLOW MIN TEMPERATURES TO PLUNGE INTO THE SINGLE
DIGITS OVER THE EXPECTED DEEPER SNOW COVERED CENTRAL AND
NORTH...WITH TEENS MAINLY SOUTH OF THE HIGHWAY 34 CORRIDOR.
TEMPERATURES COULD POTENTIALLY END UP EVEN COLDER...DEPENDING ON THE
AMOUNT OF CLOUD COVER IN THE CYCLONIC NW FLOW ALOFT. LITTLE CHANGE
IN THE SURFACE AIRMASS IS EXPECTED FOR SUNDAY UNDER A NW FLOW ALOFT
WITH HIGHS FROM THE MID 20S NE TO THE MID 30S SW
A GRADUAL WARMUP FOLLOWS FOR MONDAY THROUGH WED AS THE UPPER LEVEL
TROUGH MOVES EAST ALLOWING TO A MORE ZONAL FLOW TO DEVELOP OVER THE
CENTRAL U.S. THIS WILL LEAD TO HIGH TEMPERATURES RECOVERING FROM IN
THE 30S MONDAY...BACK TO NEAR LATE NOVEMBER NORMALS IN THE 40S BY
WED. THE NEXT SYSTEM MOVING INTO THE WEST WILL SEND ANOTHER ROUND OF
GULF MOISTURE NORTHWARD FOR INCREASING RAIN CHANCES WED NIGHT
THROUGH FRIDAY WITH TEMPERATURES LIKELY TRENDING NEAR TO ABOVE
NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1127 PM CST THU NOV 19 2015
VFR CONDITIONS TO CONTINUE OVERNIGHT WITH WINDS BECOMING LIGHT AND
VARIABLE BY DAYBREAK WITH CLEAR SKIES. A INTENSIFYING STORM SYSTEM
FROM THE NORTHERN ROCKIES WILL BRING INCREASING CLOUDS WITH LOWERING
CEILINGS THROUGH EARLY AFTERNOON AS WINDS SHIFT TO THE NORTHEAST
AT 5 TO 10 KTS. BETWEEN 20/21Z AND 21/03Z...LIGHT TO MODERATE SNOW
WILL DEVELOP WITH CEILINGS DROPPING TO AOB 1K AGL AND VISIBILITIES
AOB 1 MILE FOR IFR TO LIFT CONDITIONS. THESE CONDITIONS WILL EXTEND
PAST 21/06Z AS NORTHEAST WINDS INCREASE TO 10 TO 20 KTS BY MIDNIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON CST SATURDAY
FOR BENTON-BUCHANAN-CEDAR-CLINTON-DELAWARE-DUBUQUE-IOWA-
JACKSON-JOHNSON-JONES-KEOKUK-LINN-LOUISA-MUSCATINE-SCOTT-
WASHINGTON.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR DES MOINES-HENRY IA-JEFFERSON-LEE-VAN BUREN.
IL...WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON CST SATURDAY
FOR BUREAU-CARROLL-HENRY IL-JO DAVIESS-MERCER-PUTNAM-ROCK
ISLAND-STEPHENSON-WHITESIDE.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR HANCOCK-HENDERSON-MCDONOUGH-WARREN.
MO...WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR CLARK-SCOTLAND.
&&
$$
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...SHEETS
AVIATION...NICHOLS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
203 AM MST FRI NOV 20 2015
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 203 AM MST FRI NOV 20 2015
LATEST SATELLITE IMAGERY AND RAP H5/H7 ANALYSIS SHOWS SHORTWAVE
TROUGH OVER NORTH CENTRAL WYOMING BEGINNING TO DEEPEN WITH MAIN
MOISTURE AXIS ACROSS NORTHERN NEBRASKA AND SOUTH DAKOTA. AT THE
SURFACE LEE TROUGH IS IN PLACE OVER EASTER COLORADO WITH SOUTHERLY
GRADIENT ACROSS OUR CWA.
TODAY-TONIGHT...SHORTWAVE TROUGH IS ON TRACK TO MOVE THROUGH THE
NORTHERN PLAINS AND DEEPEN WITH A STRONG COLD FRONT DROPPING SOUTH
OVER OUR CWA BY THIS AFTERNOON AND EVENING. MOISTURE PROFILES
CONTINUE TO BE UNIMPRESSIVE...AND THE WINDOW FOR POSITIVE MOISTURE
ADVECTION NARROW. GOOD FORCING AND SPOTTY LIGHT QPF STILL SUPPORT
KEEPING SOME MENTION OF RAIN/SNOW THOUGH CONFIDENCE IS PRETTY LOW WE
WILL SEE MUCH MORE THAN VIRGA OR SPRINKLES/FLURRIES. NAM/ARW/NMM
ACTUALLY SHOW BETTER SIGNAL AFTER 06Z TONIGHT ON BACK SIDE OF UPPER
LOW ASSOCIATED WITH SECONDARY JET STREAK. I KEPT SLIGHT CHANCE POPS
LIMITED TO THE NORTH...TRANSITIONING TO THE WEST DURING THESE
PERIODS WITH SPRINKLES/FLURRIES ELSEWHERE.
WAA ASSOCIATED WITH SOUTHERLY FLOW WILL STILL SUPPORT HIGHS QUICKLY
WARMING AT LEAST IN CLOUD FREE AREAS TO THE 50S BEFORE TEMPERATURES
FALL THIS AFTERNOON BEHIND THE FRONT. LOWS TONIGHT WILL VARY BASED
ON TIMING OF WINDS DECREASING (AND SNOW PACK) AND WITH COLD CANADIAN
AIR MASS IN PLACE LOWS AROUND 10F WILL BE POSSIBLE...AND THE
POTENTIAL FOR SINGLE DIGIT LOW TEMPERATURES EXISTS IN THE WEST.
WHERE WINDS REMAIN HIGHER OVERNIGHT LOWS SHOULD BE CLOSER TO 20F.
AS WAS THE CASE YESTERDAY MODELS SHOW A STRONG PRESSURE GRADIENT
SUPPORTIVE OF AT LEAST NW WINDS GUSTING TO AROUND 40 MPH BASED ON
MIXING HEIGHTS. I STILL CANT RULE OUT SHOWERS MIXING A FEW STRONGER
GUSTS AND IF THIS CORRELATES WITH SNOW COULD REDUCE VISIBILITIES. I
DECIDED NOT TO ADD MENTION OF BLOWING SNOW TO THE GRIDS AND THE
THREAT IS VERY UNCERTAIN/ISOLATED. WILL STILL MAINTAIN MENTION IN
THE HWO.
SATURDAY-SUNDAY NIGHT...ZONAL FLOW AND A DEEP DRY AIR MASS RETURN AND
DRY CONDITIONS WILL PERSIST THROUGH THIS WEEKEND. SHALLOW/COLD AIR
MASS WILL REMAIN IN PLACE THROUGH THE DAY SATURDAY AND HIGHS WILL
GENERALLY BE IN THE 30S (NEAR FREEZING IN PROXIMITY OF SNOW FIELD).
A FEW LOCATIONS IN THE WEST COULD WARM TO AROUND 40 DEPENDING ON
MIXING. WITH INCREASING DOWNSLOPE FLOW/BUILDING LEE TROUGH WAA
INCREASES SUNDAY AND HIGHS IN THE 50S ARE EXPECTED IN AREAS WITHOUT
SNOW PACK. LOWS WILL REFLECT THE GRADUAL WARMING TREND...THOUGH WITH
GOOD RADIATION CONDITIONS/LOWER TD SATURDAY NIGHT WE SHOULD SEE LOWS
IN THE TEENS DESPITE MODERATION ALOFT.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 203 AM MST FRI NOV 20 2015
DRY AND WARM CONDITIONS ARE EXPECTED ON MONDAY AND TUESDAY AS AN
UPPER LEVEL RIDGE FLATTENS OUT ACROSS THE PLAINS AND ZONAL FLOW
DEVELOPS OVER THE REGION. A SHORTWAVE DOES LOOK TO MOVE THROUGH THE
FLOW ON TUESDAY...BUT KEPT THAT PERIOD DRY SINCE LIMITED MOISTURE
SHOULD INHIBIT PRECIP.
QUIET WEATHER PERSISTS FOR THE FORECAST AREA INTO WEDNESDAY AS
RIDGING DEVELOPS AHEAD OF THE NEXT LOW PRESSURE SYSTEM. THIS LOW
TRAVELS FROM THE NORTHWESTERN CONUS TOWARDS THE PLAINS MIDWEEK. A
STRONG COLD FRONT ASSOCIATED WITH THE SYSTEM IS CURRENTLY
ANTICIPATED TO PUSH ACROSS THE HIGH PLAINS WEDNESDAY
NIGHT/THURSDAY...GENERATING RAIN/SNOW CHANCES FOR THE AREA. ONLY
LIGHT ACCUMULATIONS ARE FORECAST AT THIS TIME. LOOKING AHEAD...IT
DOES APPEAR THAT THE REGION WILL SEE BITTER COLD TEMPERATURES JUST
AFTER THE HOLIDAY AS A COLDER AIR MASS PUSHES SOUTH.
TEMPERATURES WILL TREND DOWNWARDS DURING THE EXTENDED PERIOD WITH
HIGHS IN THE 50S ON MONDAY AND TUESDAY COOLING INTO THE UPPER 40S TO
MID 50S FOR WEDNESDAY. THE AREA SHOULD START TO SEE A STEEPER
DECREASE IN TEMPERATURES TOWARDS THE END OF THE WORK WEEK AFTER THE
PASSAGE OF THE COLD FRONT...WITH HIGHS FORECAST IN THE UPPER 30S TO
MID 40S ON THURSDAY. LOWS ARE EXPECTED TO BE IN THE 20S TO LOW 30S
THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1047 PM MST THU NOV 19 2015
VFR CONDITIONS WILL PERSIST AT GLD AND MCK THROUGH TONIGHT AND
THROUGH MUCH OF THE DAY TOMORROW. CLOUD COVER IS EXPECTED TO
INCREASE WITH CEILINGS LOWERING AFTER 18Z. WITH THE FRONTAL
PASSAGE EXPECTED BY 20Z TOMORROW AT BOTH LOCATIONS...LIGHT SOUTH
WINDS WILL TURN SOUTHWEST AND THEN BECOME GUSTY OUT OF THE
NORTHWEST BY 21Z. SUSTAINED WINDS SPEEDS OF 20-25KTS WILL BE
COMMON WITH GUSTS TO 30-35 KTS BETWEEN 21Z AND 04Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...LOCKHART
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
323 AM EST FRI NOV 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM EST FRI NOV 20 2015
AN UPPER TROUGH OVER ONTARIO IS LEADING TO THE COLDEST AIR THAT WE
HAVE SEEN THIS FALL...WITH 850MB TEMPS -12C AT KINL AT 00Z AND THAT
MATCHES THE RAP ANALYSIS OVER WESTERN LAKE SUPERIOR. A SECONDARY
TROUGH ASSOCIATED WITH THE STRONG LOW OVER HUDSON BAY IS SLOWLY
MOVING EAST ACROSS CENTRAL LAKE SUPERIOR AT THIS TIME AND HAS
SHIFTED WINDS MORE TO THE WEST OVER WESTERN LAKE SUPERIOR. THE COLD
TEMPS HAVE LED TO LAKE EFFECT SNOW IN THE WESTERLY WIND SNOW BELTS.
LOOKING AT WEBCAMS...IT IS TOUGH TO GET A HANDLE ON THE AMOUNT OF
SNOW THAT HAS FALLEN DUE TO THE STRONG WINDS...BUT IT LOOKS TO HAVE
PRODUCED A FEW INCHES IN THE HOUGHTON/CALUMET AREA. THE WINDS HAVE
HELPED CONTRIBUTE TO VISIBILITIES FALLING TO OR BELOW A MILE AT
TIMES AS THEY CONTINUE TO GUST TO 35-40KTS IN THE KEWEENAW.
EXPECT THE LAKE EFFECT TO CONTINUE THROUGH THE SHORT TERM
PERIOD...BUT THE INTENSITY SHOULD BE ON THE DECREASE DUE TO SEVERAL
FACTORS. FIRST...THE DEEP MOISTURE DIMINISHES AS AN UPPER RIDGE
MOVES OVER THE AREA TODAY AHEAD OF A SECONDARY TROUGH MOVING THROUGH
THE NORTHERN ROCKIES. SUBSIDENCE ALOFT WITH THAT RIDGING WILL HELP
LOWER INVERSION HEIGHTS THROUGH THE DAY TOWARDS 7-8KFT (FROM THE
PRESENT 10KFT). SECOND...THE INCREASED CONVERGENCE SEEN ALONG AND
JUST BEHIND THE SURFACE TROUGH WILL DIMINISH THROUGH THE MORNING
HOURS AS THE WINDS BECOME FAIRLY UNIFORM AROUND 270-280 DEGREES.
THERE IS A SECONDARY TROUGH THAT WILL MOVE THROUGH LATE THIS
AFTERNOON AND EARLY THIS EVENING...AND SHIFT WINDS AROUND TO MORE
290-300 DEGREES. THAT WILL BRING MORE LOCATIONS IN THE WESTERN AND
EASTERN U.P. UNDER SOME LAKE EFFECT SNOW (TRADITIONAL NW WIND SNOW
BELTS). ONE OTHER LIMITING FACTOR WILL BE THE CONTINUED INDICATION
BY THE MODELS OF AN INVERTED-V LOOK TO THE LOW LEVELS. THAT BEING
SAID...THE WEAKENING WINDS WILL INCREASE RESIDENCE TIME AND LEAD TO
LESS FRACTURING OF THE FLAKES FOR TONIGHT...SO WOULDN/T BE SURPRISED
TO SEE A FEW LOCATIONS PICKING UP ONE TO LOCALLY TWO INCHES AS MUCH
OF THE CLOUD WILL BE WITHIN THE DGZ. FOR TODAY...EXPECT DAYTIME
ACCUMULATIONS OF 1-2 INCHES OVER THE KEWEENAW AND MAYBE A TOUCH MORE
OVER FAR NORTHEAST LUCE COUNTY WHERE THE LONGER FETCH WILL CREATE
STRONGER BANDS THAT WILL SHIFT SOUTH ALONG THE LUCE COUNTY SHORELINE
IN THE AFTERNOON. AT THIS POINT...THE 15Z END TIME TO THE WINTER WX
ADVISORY LOOKS PRETTY GOOD AS THAT MATCHES UP WELL WITH THE
DIMINISHING TREND IN BOTH THE WINDS AND DEEPER MOISTURE.
WHILE WINDS ARE STILL GUSTING TO 40KTS OVER PORTIONS OF LAKE
SUPERIOR AND THE KEWEENAW PENINSULA AS OF 3AM...THE WEAKENING
PRESSURE GRADIENT THROUGH THE DAY WILL LEAD TO STEADILY DIMINISHING
WINDS THROUGH THE DAY AND EXPECT THEM TO FALL BELOW GALES OVER LAKE
SUPERIOR BY EARLY EVENING. THAT DIMINISHING WILL CONTINUE THROUGH
THE NIGHT AS THEY SHIFT TO THE NORTHWEST. FINALLY...HIGHS TODAY WILL
RANGE FROM THE UPPER 20S OVER THE WEST TO THE LOWER 30S OVER THE
EAST.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 440 PM EST THU NOV 19 2015
A RETURN TO COLDER...MORE SEASONABLE NOV WX IS IN STORE THIS WEEKEND
AS A SHRTWV DIGGING INTO THE PLAINS AMPLIFIES AN UPR TROF OVER THE
GREAT LKS. ALTHOUGH MUCH OF THE SYNOPTIC SN ASSOCIATED WITH THE
ACCOMPANYING SFC LO TRACKING THRU THE LOWER LKS WL MISS THE CWA TO
THE S...SOME LES WL BE LIKELY IN THE FAVORED SN BELTS NEAR LK SUP.
THERE COULD BE ANOTHER PERIOD OF SN ON SUN NGT INTO MON BEFORE A
PATTERN CHANGE THAT FEATURES A BLDG UPR RDG OVER THE ERN CONUS/
DOWNSTREAM OF TROFFING OVER THE W BRINGS A RETURN OF MILDER WX THE
MIDDLE OF NEXT WEEK. THE EXTENDED FCST FOR THANKSGIVING DAY MAY
INCLUDE SOME RAIN AS A STRENGTHENING SLY FLOW TO THE E OF A LO PRES
MOVING NEWD THRU THE PLAINS ADVECTS MOISTER AIR INTO THE UPR LKS.
FRI NGT...SHRTWV DIGGING INTO THE PLAINS IS FCST TO AMPLIFY UPR TROF
AXIS CENTERED OVER THE NRN PLAINS. AN ACCOMPANYING SFC LO PRES WL BE
TAKING SHAPE OVER THE MID MS RIVER VALLEY BY 12Z. OVER UPR MI...A
CYC WNW FLOW IS FCST TO WEAKEN AND GIVE WAY TO A WEAK HI PRES RDG
AXIS NOSING INTO THE UPR LKS TO THE N OF THE DVLPG LO TO THE S. LES
IN THE CHILLY WNW SLOWLY VEERING NW FLOW...WITH H85 TEMPS ARND
-12C...WL PERSIST THRU THE NGT BUT BE LIMITED IN INTENSITY AND
COVERAGE BY LARGER SCALE DEEP LYR QVECTOR DVGC/SUBSIDENCE...ABSENCE
OF SHARP LLVL CNVGC...AND LLVL DRY AIR THAT SHOWS UP AS AN INVERTED
V T/TD PROFILE ON FCST SDNGS.
SAT/SAT NGT...DEEPENING SFC LO PRES AHEAD OF DIGGING SHRTWV IS FCST
TO MOVE TO SE LOWER MI BY 00Z SUN AND THEN TO NEAR THE ONTARIO/
QUEBEC BORDER JUST S OF JAMES BAY AT 12Z SUN. THE 12Z GFS/00Z
CNDN/09Z SREF MODELS SHOW A SOMEWHAT DEEPER SFC LO PRES/SHARPER CYC
FLOW AND FARTHER W TRACK ASSOCIATED WITH MORE PHASING BTWN THE
DIGGING SHRTWV AND ANOTHER DISTURBANCE FARTHER TO THE N IN MN. THESE
MODELS INDICATE THE NW EDGE OF THE SHARPER FORCING WL AT LEAST BRUSH
THE SE CWA SAT AFTN/EVNG. SINCE THE 00Z GFS ENSEMBLE MEAN SUPPORTS
THE SOMEWHAT WEAKER/FARTHER E TRACK DEPICTED BY THE 12Z NAM/12Z
CNDN/00Z AND 12Z ECMWF...WL TEND TOWARD THAT SCENARIO PER THE LATEST
NCEP GUIDANCE. EVEN IF THE 12Z GFS IS CORRECT...FCST H7-75 SPECIFIC
HUMIDITY JUST A BIT MORE THAN 1 G/KG OVER THE SE CWA WOULD SUPPORT
ONLY AN INCH OR TWO OF SN DURING THE 6-9 HR PERIOD THE DEEP LYR
QVECTOR CNVGC IS FCST TO BE IN PLACE. OF MORE CONCERN IS THE
POTENTIAL FOR LK EFFECT SN NEAR LK SUP AS H85 TEMPS NEAR -15C DROP
OVER THE UPR LKS IN THE EXPECTED LLVL NNW FLOW AND UNDER AN AREA OF
SOME DEEPER MSTR. NAM FCST SDNGS FOR IRONWOOD AND NEWBERRY SHOW SOME
FAIRLY SHARP UVV AT TIMES WITHIN THE DGZ RANGING IN HGT FM 3-8K FT
AGL ON SAT AND SAT NGT. SO LES AT SOME LOCATIONS IN THE FAVORED SN
BELTS MAY AT LEAST APRCH ADVY CRITERIA DURING THIS PERIOD. SLOWLY
SHIFTING WINDS THAT LIMIT SN BAND RESIDENCE TIME WL LOWER THIS
POTENTIAL.
SUN...AS THE CNDN LO SHIFTS TO THE NE INTO NRN QUEBEC...A TRAILING
SFC RDG AXIS IS FCST TO PUSH W-E THRU THE UPR LKS. THE COMBINATION
OF THE INCRSG ACYC FLOW/LLVL DRYING AND DEEP LYR QVECTOR DVGC WL
DIMINISH LINGERING LES. BUT FCST WL SHOW CATEGORICAL LES POPS IN THE
SN BELTS E OF MARQUETTE DURING THE MRNG BEFORE THE CLOSER APRCH OF
THE RDG AXIS IN THE AFTN. ALTHOUGH THERE WL BE AT LEAST SOME PARTIAL
CLRG AS WELL WITH THE ARRIVAL OF THE RDG AXIS... INCRSG SW FLOW/
ISENTROPIC ASCENT ON THE WRN FLANK OF THE PASSING RDG AXIS AND AHEAD
OF NEXT SHRTWV/SFC LO DIGGING SE THRU SCENTRAL CANADA WL BRING
INCRSG MID CLDS DURING THE AFTN.
SUN NGT/MON...NEXT SHRTWV IS PROGGED TO SLIDE SE NEAR OR JUST TO THE
N OF UPR MI. THE 00Z ECWMF SHOWED THE FARTHER N TRACK...WHILE THE
12Z CNDN MODEL IS FARTHER S WITH THE DISTRUBANCE/SFC LO TRACKING
OVER UPR MI. BAND OF INCRSG MID LVL MSTR TIED BEST TO ISENTROPIC
ASCENT SHOWN ON THE 280-285K SFCS WL SUPPORT AT LEAST A CHC OF SOME
SNOW...WITH TRACK OF DISTURBANCE KEY IN THE LOCATION OF THE HIER
POPS. CONSIDERING THE UNCERTAINTY ON THE TRACK OF THE DISTURBANCE...
FCST WL SHOW NO HIER THAN CHC POPS. IF THE FARTHER N TRACK OF THE
DISTURBANCE VERIFIES...SOME LK ENHANCEMENT OFF LK MI COULD AT LEAST
BRUSH THE FAR ERN CWA WITH H85 TEMPS ARND -9C IN LLVL SSW FLOW ON
SUN NGT FOR AT LEAST A SHORT TIME.
MON NGT INTO TUE...NW FLOW ON THE BACK SIDE OF DEPARTING SHRTWV/SFC
LO WL ADVECT AIR SUFFICIENTLY COLD...WITH H85 TEMPS AS LO AS -8C TO -
9C... TO SUPPORT AT LEAST A CHC FOR SOME LES IN THE FAVORED SN BELTS
INTO TUE MRNG.
EXTENDED...ARRIVAL OF SFC HI PRES RDG UNDER BLDG UPR RDG SHOULD
RESULT IN DRY WX AT LEAST ON TUE. AS THE SLY FLOW BTWN THE HI PRES
EXITING TO THE E TOWARD NEW ENGLAND DVLPG LO PRES IN THE WRN PLAINS
ADVECTS WARMER...MOISTER AIR TOWARD THE UPR LKS ON WED/THU THERE WL
BE INCRSG CLDS AND AT LEAST A CHC OF SOME RAIN...ESPECIALLY ON
THANKSGIVING DAY WHEN A DEEPER SFC LO PRES RIDING TO THE NE ON STNRY
FNT STRETCING FM THE SRN PLAINS INTO THE UPR MS RIVER VALLEY GETS
CLOSER. TEMPS ON WED/THANKSGIVING WL RUN WELL ABOVE NORMAL AS H85
TEMPS ARE FCST TO REACH ARND 6C ON THU.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1231 AM EST FRI NOV 20 2015
WINDY CONDITIONS WILL CONTINUE AT ALL SITES THROUGH TONIGHT BEFORE
GRADUALLY DIMINISHING THROUGH THE DAY FRIDAY. WESTERLY GUSTS AS HIGH
AS 40 KTS ARE EXPECTED AT CMX THAT WILL TAPER OFF SLIGHTLY
OVERNIGHT. CMX THROUGHTHIS EVENING...WHILE GUSTS OF 25-305 KNOTS ARE
EXPECTED FOR IWD AND SAW.
HEAVIER LAKE EFFECT SNOW BANDS ARE FORECAST TO FOCUS ACROSS THE
KEWEENAW PENINSULA OVERNIGHT. THIS COMBINED WITH THE GUSTY WINDS
WILL LIKELY BRING IFR TO POSSIBLY LIFR VIS TO CMX VSBY WITH MAINLY
MVFR CIGS THROUGH MUCH OF THE NIGHT. VSBY WILL IMPROVE TO MVFR BY
FRI AFTERNOON AS DRIER AIR MOVES INTO THE REGION. AT IWD AND
SAW...HIGH-END MVFR TO LOW-END VFR CIGS AND ISOLATED TO SCATTERED -
SHSN ARE FORECAST THROUGH THE PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 322 AM EST FRI NOV 20 2015
A TROUGH ASSOCIATED WITH A STRONG LOW PRESSURE SYSTEM OVER HUDSON
BAY WILL CROSS LAKE SUPERIOR THIS EVENING. OVER-WATER INSTABILITY
COMBINED WITH A STRONG PRESSURE GRADIENT WILL RESULT IN WSW STORM
FORCE WINDS TO 50 KNOTS FOR MUCH OF THE OPEN WATERS OF WEST AND
CENTRAL LAKE SUPERIOR THIS EVENING. ONCE THE TROUGH COMPLETELY
CROSSES THE LAKE OVERNIGHT...WINDS WILL SHIFT TO THE WEST AND GUST
TO GALES TO 35-40 KTS THROUGH MUCH OF FRIDAY. THESE STRONG WINDS
WILL DIMINISH STEADILY TO UNDER 25 KTS ON FRI NIGHT/SAT WITH THE
APPROACH OF A WEAK HI PRESSURE RIDGE. A STRONGER N TO NW FLOW UP TO
30 KTS IS POSSIBLE ON SAT NIGHT DEPENDING ON THE TRACK OF A LO PRES
MOVING NE THRU SE ONTARIO. THE FLOW WILL THEN SHIFT TO THE SW UP TO
25 KTS BY LATE SUN INTO MON AS A TRAILING HI PRES RIDGE CROSSES THE
UPPER LAKES AND AHEAD OF ANOTHER LO PRES TROUGH APPROACHING FROM THE
NW. FOLLOWING THE TROF PASSAGE...EXPECT W TO NW WINDS UP TO 25 KTS
ON MON INTO TUE...BUT THEN WINDS WILL SHIFT BACK TO THE SW BY
LATER ON TUE AFTER TRAILING HI PRES SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR MIZ001-
003.
LAKESHORE FLOOD ADVISORY UNTIL 10 AM EST THIS MORNING FOR MIZ001-
003.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ248>251-264>267.
GALE WARNING UNTIL 5 PM EST /4 PM CST/ THIS AFTERNOON FOR
LSZ240>245.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LSZ246-247.
GALE WARNING UNTIL 4 PM EST /3 PM CST/ THIS AFTERNOON FOR LSZ162-
263.
LAKE MICHIGAN...
GALE WARNING UNTIL 10 AM EST THIS MORNING FOR LMZ221-248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...JLB
MARINE...SRF
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
355 AM CST FRI NOV 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CST FRI NOV 20 2015
PRESENT RADAR SHOWING DEVELOPING SNOW BAND FROM SOUTHWESTERN SOUTH
DAKOTA TO NORTH CENTRAL NEBRASKA VERY EARLY THIS MORNING...THOUGH
NOT SEEING ANY SNOW REACHING THE GROUND ON THE EASTERN EXTENT OF THE
BAND WITH DRY LOW LEVEL AIR IN PLACE. THIS AREA OF SNOW LOOKS TO BE
COLLOCATED WELL WITH MODEL 700 MB FRONTOGENESIS FIELDS. STILL LOOKING
AT A DECENT SNOW EVENT ACROSS THE AREA TODAY WITH STRENGTHENING MID
LEVEL FRONTOGENESIS AND UPPER LEVEL LIFT AIDED BY A JET STREAK
SITUATED THROUGH NORTHERN SOUTH DAKOTA INTO MINNESOTA. MODELS IN
FAIRLY DECENT AGREEMENT ON A STRONG FRONTOGENETIC BAND DEVELOPING
INTO SOUTH CENTRAL SOUTH DAKOTA IN THE EARLY MORNING...THEN
SPLITTING TO THE NORTH AND SOUTH BY LATE MORNING...WITH THE SOUTHERN
BAND BECOMING DOMINATE OVER NORTHWESTERN IOWA BY AFTERNOON AS
OPTIMUM 500-300 MB DIV Q SLIDES THROUGH SOUTHERN SOUTH DAKOTA AND
NEBRASKA DURING THAT TIME FRAME. THIS SCENARIO POINTS TO HEAVY SNOW
DEVELOPING SOUTH OF INTERSTATE 90 DURING THE DAY...WITH AMOUNTS
DECREASING RAPIDLY TO THE NORTH WHERE DRIER AIR WILL BE GREATER AND
FORCING IS LESS. WHAT IS SOMEWHAT DISTURBING IS THAT MOST RECENT
MODEL RUNS...INCLUDING THE RAP AND HRRR ARE TRENDING FARTHER TO THE
NORTH WITH THE MORNING PERIOD SNOWFALL IN THE INITIAL FRONTOGENETIC
BAND...PLACING IT RIGHT ALONG THE INTERSTATE 90 CORRIDOR...BEFORE
COLLAPSING IT SOUTHWARD BY AFTERNOON AS EXPLAINED ABOVE. IN
ADDITION...THEY ARE HINTING AT SOME INSTABILITY OF THE FRONT SO
THERE COULD BE A PERIOD OF HEAVIER SNOWFALL IN THIS VICINITY DURING
THE MORNING HOURS. STILL THINKING THE GENERAL HEAVIER SNOW WILL BE
SOUTH OF I90 FOR MOST OF THE DAY...BUT WILL BE SOMETHING TO KEEP AN
EYE ON. WINDS WILL REMAIN ON THE LIGHTER SIDE TODAY...SO BLOWING
SNOW SHOULD NOT BE AN ISSUE. REMAINED BELOW GUIDANCE WITH RESPECT TO
TEMPERATURES...WITH PRECIPITATION AND WET BULBING EFFECTS...SO
LOOKING AT HIGHS JUST EITHER SIDE OF 30 DEGREES. USING SNOW RATIOS
IN THE RANGE OF 11:1 TO 15:1 AND CURRENTLY PROJECTED TOTAL SNOWFALL
AMOUNTS RANGE FROM JUST UNDER AN INCH ALONG THE HIGHWAY 14
CORRIDOR...TO 4 TO 6 INCHES ALONG THE I90 CORRIDOR...TO 6 TO 9
INCHES SOUTH OF THAT AREA...TRENDING HIGHEST TOWARD NORTHWESTERN
IOWA. IN LIGHT OF ALL THE ABOVE REASONING...ISSUED A WINTER WEATHER
ADVISORY ONE STRIP OF COUNTIES FARTHER TO THE NORTH THAN PREVIOUS
FORECAST...ALONG THE I90 CORRIDOR...WITH A WINTER STORM WARNING FOR
AREAS TO THE SOUTH.
BY THIS EVENING THE MIDLEVEL FRONTOGENETIC FORCING SLIDES EASTWARD
INTO NORTH CENTRAL AND NORTHEASTERN IOWA WITH MAXIMUM UPPER LEVEL
DIV Q FOLLOWING SUIT. WITH THAT...WILL SEE SNOW TAPER OFF FROM WEST
TO EAST DURING THE EVENING. MAY GET SOME CLEARING LATER IN THE
NIGHT...AND WENT ON THE LOWER SIDE OF GUIDANCE...ESPECIALLY IN
EXPECTED SNOW COVERED AREAS...WITH OVERNIGHT READINGS IN THE MID
TEENS NORTH TO AROUND 10 SOUTH OF THE I90 CORRIDOR.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 354 AM CST FRI NOV 20 2015
A DRY FIRST HALF OF THE MEDIUM RANGE FORECAST...WITH MORE UNSETTLED
WEATHER TAKING AIM FOR THE THANKSGIVING HOLIDAY. EARLY ON THIS
WEEKEND...BEHIND TODAYS DEPARTING SNOWSTORM...THE MAIN CONCERN WILL
BE WITH TEMPERATURES. THE FIRST COLD DAY OF THE LATE FALL AND EARLY
WINTER SEASON WILL ARRIVE ON SATURDAY. FRESH SNOW COVER...COMBINED
WITH H850 MB TEMPERATURES -10 TO -14C WILL KEEP TEMPERATURES WELL
BELOW NORMAL THIS WEEKEND. SATURDAYS HIGHS MAY STRUGGLE TO BREAK
FREE FROM THE MID 20S. ON SUNDAY...WE WILL HAVE A RETURN OF
SOUTHWESTERLY BOUNDARY LAYER AND LOW LEVEL FLOW...BUT FRESH SNOW
COVER WILL AGAIN HAMPER TEMPERATURES SIGNIFICANTLY.
QUIET WEATHER THROUGH THE FIRST HALF OF NEXT WEEK AS RIDGING SPREADS
ACROSS THE CENTRAL UNITED STATES. WARM SOUTHERLY FLOW SHOULD BUMP
TEMPERATURES BACK INTO THE 40S AND SHOULD MELT SOME OF THE SNOWPACK.
THE CONCERN COULD THEN TURN TO FOG POTENTIAL IN THE MIDWEEK
TIMEFRAME.
WHILE STILL EARLY...WE WILL HAVE TO KEEP AN EYE ON A DEEP UPPER
THROUGH DIGGING INTO THE SOUTHWESTERN US THIS WEEK. THIS SYSTEM
COULD BRING MESSY WEATHER INTO THE MIDDLE OF THE COUNTRY FOR THE
THANKSGIVING HOLIDAY. MODELS SEEM TO AGREE THAT A COLD FRONT WILL
SURGE THROUGH THE REGION LATE WEDNESDAY INTO THURSDAY. CONSIDERABLE
UPPER LIFT MAY SPREAD ACROSS THE REGION WITH THE H850 BOUNDARY
LINGERING OVER THE COLDER SFC AIR. THIS SOLN COULD PRODUCE A MYRIAD
OF WINTRY WEATHER IN THE LOCAL AREA BY THANKSGIVING AND THE DAY
AFTER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 529 PM CST THU NOV 19 2015
MAIN AVIATION CONCERN IS THE LATE MORNING AND AFTERNOON HOURS ON
FRIDAY...WHEN A BAND OF SNOW WILL MOVE ACROSS THE FORECAST...MOST
ACUTE ALONG INTERSTATE 90 AND SOUTHWARD. THEREFORE HAVE LIFR TO
IFR CONDITIONS FOR THE KFSD AND KSUX TAF SITES...KEEPING KHON AT
MVFR WHO SHOULD BE TOO FAR NORTH TO GET HEAVY SNOW.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR SDZ063>071.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR SDZ050-
057>061.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR SDZ062.
MN...WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR MNZ089-090-098.
IA...WINTER STORM WARNING FROM 9 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR IAZ001>003-012-013-020.
WINTER STORM WARNING FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR IAZ014-021-022-031-032.
NE...WINTER STORM WARNING FROM 9 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR NEZ013-014.
&&
$$
SHORT TERM...JM
LONG TERM...DUX
AVIATION...MJ
AREA FORECAST DISCUSSION...UPDATED
NWS QUAD CITIES IA IL
524 AM CST FRI NOV 20 2015
.SYNOPSIS...
ISSUED AT 328 AM CST FRI NOV 20 2015
CURRENT SATELLITE IMAGERY DEPICTS CLEAR SKIES TONIGHT AS HIGH
PRESSURE IS IN PLACE ACROSS THE REGION. AT THE SFC...DRY AIR IS IN
PLACE WITH DEWPOINTS IN THE LOW 20S TO UPPER TEENS. OVER THE FAR
NORTHERN CONUS ROCKY MOUNTAINS...AN UPPER LEVEL WAVE WAS MOVING SE
INTO THE HIGH PLAINS. THIS WAVE IS EXPECTED TO BRING OUR FIRST
WINTER STORM TO THE AREA LATER TODAY AND OVERNIGHT AND INTO SATURDAY
MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 328 AM CST FRI NOV 20 2015
MAIN FORECAST CONCERN FOR THE SHORT TERM IS THE IMPENDING WINTER
STORM TO AFFECT THE AREA TODAY AND TONIGHT. OVERALL FORECAST HAS
CHANGED LITTLE WITH THE MOST NOTABLE CHANGE WITH A SHIFT SOUTH OF
THE HEAVY SNOW AXIS. GUIDANCE SUGGESTS THAT PRECIP COULD START AS
EARLY AS 18Z ACROSS THE FAR NORTHERN ZONES. OVERALL NO CHANGES TO
THE CURRENT HEADLINES WERE MADE.
H5 WAVE IS FORECAST TO MOVE INTO THE CENTRAL PLAINS BY 18Z TODAY.
MODELS ARE CONSISTENT WITH THE PLACEMENT OF THE MAIN FORCING. THE
GFS IS THE FASTEST OF THE OPERATIONAL MODELS AND THIS SEEMS TO BE
SLIGHTLY SLOWER THAN THE GEFS ENSEMBLE MEAN. BETWEEN 00Z AND 12Z
SATURDAY A H3 JET IS EXPECTED TO PASS TO OUR SOUTH WITH THE
FAVORABLE LEFT EXIT REGION OVER OUR AREA. THIS WILL HELP TO
INCREASE VERTICAL MOTION FROM 00Z TO 12Z SATURDAY. THE H85 LOW
CENTER IS FORECAST TO MOVE JUST TO OUR SOUTH THROUGH THE PERIOD
WITH THE MAJORITY OF THE CWA IN THE BELOW FREEZING SIDE.
MODEL SOUNDINGS ARE INDICATIVE OF SNOW AS SOON AS EVAPORATIVE
COOLING RAPIDLY COOLS THE LOW LEVELS. ONSET OF PRECIP LOOKS TO BE
RAIN AT FIRST...QUICKLY CHANGING TO RASN AND THEN OVER TO ALL SN
SHORTLY AFTER THIS.
TIMING...HIRES GUIDANCE IS HINTING AT A BAND OF PRECIP ACROSS FAR
NORTHERN ZONES AS EARLY AS 18Z. THIS BAND MAY BE LIGHT AT FIRST
AND MAY TAKE SOME TIME TO COOL/MOISTEN UP THE BL BEFORE PRECIP
STARTS TO FALL. THE REST OF THE AREA WILL SEE THE PRECIP START
FROM WEST TO EAST. THE BEST CHANCE FOR ONSET IN THE WEST WILL BE
BETWEEN 20Z AND 22Z. MULTIPLE HRRR RUNS ARE CONSISTENT IN THIS
TIMING. THE HRRR AND OTHER CAMS SUGGEST A 23Z TO 01Z START TIME
FOR THE AREAS ALONG THE MISSISSIPPI RIVER. AREAS ACROSS IL COULD
SEE PRECIP START AS SOON AS 00Z...BUT LIKELY 01Z TO 02Z.
SNOWFALL TOTALS HAVE NOT CHANGED ALL THE MUCH. WITH THE LATEST
GUIDANCE AND TRENDS FROM DPROG DT...IT APPEARS THAT THE HEAVIEST
SNOW HAS SHIFTED SOUTH SOME 40 MILES. THIS PUTS A ROCKFORD TO
CLINTON TO IOWA CITY LINE AS OUR CURRENT BEST GUESS FOR THE
HEAVIEST SNOW AXIS. TOTALS OF UP TO TEN INCHES OR MORE COULD BE
POSSIBLE ALONG THE AXIS.
SOME CONCERNS ABOUT THE FORECAST ARE THE WARM GROUND TEMPS AND THE
EFFECTS OF EVAPORATIVE COOLING. WHILE THE QPF AND SNOW RATIOS
SUPPORT THIS MUCH SNOW...THERE IS A POSSIBILITY THAT THE WARM
GROUND WILL MELT SNOW AND LEAD TO LESS ACCUMULATION THAN FORECAST.
THIS NEEDS TO BE KEPT IN MIND. REGARDLESS OF THE ACTUAL
TOTALS...IMPACTS FROM THIS STORM WILL LIKELY CAUSE DRIVING ISSUES
AS THE SNOW RATE MAY MAKE IT DIFFICULT TO KEEP ROADS CLEARED
...ESPECIALLY LATER AT NIGHT AND IN THE HEAVIER BANDS. THERE ARE
SOME CONCERNS ABOUT ICE FORMING ON UNTREATED ROADWAYS SO BE SURE
TO DRIVE CAUTIOUSLY IF YOU MUST BE OUT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 328 AM CST FRI NOV 20 2015
INITIAL FOCUS IS ON THE EXITING WINTER STORM SATURDAY MORNING...
WHICH WILL BE FOLLOWED BY BITTER COLD TEMPERATURES THROUGH SUNDAY. A
RETURN TO A MORE ZONAL UPPER LEVEL FLOW NEXT WEEK WILL RESULT IN
TEMPERATURES RECOVERING BACK TO NEAR NORMAL WITH INCREASING RAIN
CHANCES IN THE LATTER HALF OF THE WEEK AS GULF MOISTURE RETURNS.
MODEL CONSENSUS HAS THE SURFACE LOW OVER W CENTRAL IL AT 12Z
DEEPENING AND EJECTING NORTHEAST INTO THE GREAT LAKES WITH THE
PASSAGE OF THE UPPER LEVEL VORT MAX FOLLOWED BY ISENTROPIC DOWNGLIDE
AND BRISK WINDS BEHIND THE SYSTEM. THE TIMING OF THE BACK EDGE OF
THE SYSTEM AND THE PASSING DEFORMATION AXIS NW OF THE SURFACE AND
850 MB LOWS HAS BEEN FAIRLY CONSISTENT OVER THE PAST SEVERAL MODEL
RUNS. THIS SUGGESTS ADDITIONAL 1 TO 2 INCH ACCUMULATIONS WILL BE
POSSIBLE PRIMARILY OVER NW IL...WITH TRACE TO QUARTER INCH AMOUNTS
FURTHER WEST AND SOUTH. HOWEVER...EVEN WITHOUT SIGNIFICANT
SNOW...BRISK N-NW WINDS OF 15 TO 25 MPH...POSSIBLY INTO THE 30 MPH
RANGE...MAY CAUSE SOME DRIFTING SNOW ACROSS THE WEST THROUGH THE
MORNING AND WILL KEEP THE CURRENT 18Z EXPIRATION TIME OF THE
HEADLINES GOING FOR NOW. STRONG COLD AIR ADVECTION AND FRESH
SNOWFALL WILL LEAD TO A WINTER-LIKE DAY WITH TEMPERATURES STEADY TO
FALLING THROUGH THE MID TO UPPER 20S EVEN AS THE DEVELOPING LOW
LEVEL ANTICYCLONIC FLOW LEADS TO BREAKS OF SUNSHINE BY AFTERNOON.
SATURDAY NIGHT AND SUNDAY...LIGHTER SURFACE WINDS WITH THE PASSAGE
OF RIDGE AXIS WILL ALLOW MIN TEMPERATURES TO PLUNGE INTO THE SINGLE
DIGITS OVER THE EXPECTED DEEPER SNOW COVERED CENTRAL AND
NORTH...WITH TEENS MAINLY SOUTH OF THE HIGHWAY 34 CORRIDOR.
TEMPERATURES COULD POTENTIALLY END UP EVEN COLDER...DEPENDING ON THE
AMOUNT OF CLOUD COVER IN THE CYCLONIC NW FLOW ALOFT. LITTLE CHANGE
IN THE SURFACE AIRMASS IS EXPECTED FOR SUNDAY UNDER A NW FLOW ALOFT
WITH HIGHS FROM THE MID 20S NE TO THE MID 30S SW
A GRADUAL WARMUP FOLLOWS FOR MONDAY THROUGH WED AS THE UPPER LEVEL
TROUGH MOVES EAST ALLOWING TO A MORE ZONAL FLOW TO DEVELOP OVER THE
CENTRAL U.S. THIS WILL LEAD TO HIGH TEMPERATURES RECOVERING FROM IN
THE 30S MONDAY...BACK TO NEAR LATE NOVEMBER NORMALS IN THE 40S BY
WED. THE NEXT SYSTEM MOVING INTO THE WEST WILL SEND ANOTHER ROUND OF
GULF MOISTURE NORTHWARD FOR INCREASING RAIN CHANCES WED NIGHT
THROUGH FRIDAY WITH TEMPERATURES LIKELY TRENDING NEAR TO ABOVE
NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 515 AM CST FRI NOV 20 2015
FIRST WINTER STORM THIS SEASON WILL AFFECT THE TAF SITES THROUGH
THIS PERIOD. WITH THE EXCEPTION OF POSSIBLY CID...ALL OTHER TAF
SITES WILL HAVE VFR FLIGHT RULES WITH NO WX THROUGH 21Z TODAY. RA
WILL TRANSITION TO RASN AND THEN SNOW QUICKLY AND AFFECT ALL THE
TAF SITES. SN+ WITH LESS THAN 1/4 VSBY WILL OCCUR...HOWEVER TIMING
OF THESE WINDOWS IS NOT GOOD SO WILL LEAVE THEM OUT UNTIL LATER.
THOSE FLYING LATER IN THE DAY AND OVERNIGHT SHOULD BE PREPARED FOR
IFR AND LIFR AND FROZEN PRECIP. SNOW SHOULD END FROM W TO E NEAR
DAYBREAK SAT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON CST SATURDAY
FOR BENTON-BUCHANAN-CEDAR-CLINTON-DELAWARE-DUBUQUE-IOWA-
JACKSON-JOHNSON-JONES-KEOKUK-LINN-LOUISA-MUSCATINE-SCOTT-
WASHINGTON.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR DES MOINES-HENRY IA-JEFFERSON-LEE-VAN BUREN.
IL...WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON CST SATURDAY
FOR BUREAU-CARROLL-HENRY IL-JO DAVIESS-MERCER-PUTNAM-ROCK
ISLAND-STEPHENSON-WHITESIDE.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR HANCOCK-HENDERSON-MCDONOUGH-WARREN.
MO...WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR CLARK-SCOTLAND.
&&
$$
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...SHEETS
AVIATION...GIBBS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
423 AM MST FRI NOV 20 2015
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 203 AM MST FRI NOV 20 2015
LATEST SATELLITE IMAGERY AND RAP H5/H7 ANALYSIS SHOWS SHORTWAVE
TROUGH OVER NORTH CENTRAL WYOMING BEGINNING TO DEEPEN WITH MAIN
MOISTURE AXIS ACROSS NORTHERN NEBRASKA AND SOUTH DAKOTA. AT THE
SURFACE LEE TROUGH IS IN PLACE OVER EASTER COLORADO WITH SOUTHERLY
GRADIENT ACROSS OUR CWA.
TODAY-TONIGHT...SHORTWAVE TROUGH IS ON TRACK TO MOVE THROUGH THE
NORTHERN PLAINS AND DEEPEN WITH A STRONG COLD FRONT DROPPING SOUTH
OVER OUR CWA BY THIS AFTERNOON AND EVENING. MOISTURE PROFILES
CONTINUE TO BE UNIMPRESSIVE...AND THE WINDOW FOR POSITIVE MOISTURE
ADVECTION NARROW. GOOD FORCING AND SPOTTY LIGHT QPF STILL SUPPORT
KEEPING SOME MENTION OF RAIN/SNOW THOUGH CONFIDENCE IS PRETTY LOW WE
WILL SEE MUCH MORE THAN VIRGA OR SPRINKLES/FLURRIES. NAM/ARW/NMM
ACTUALLY SHOW BETTER SIGNAL AFTER 06Z TONIGHT ON BACK SIDE OF UPPER
LOW ASSOCIATED WITH SECONDARY JET STREAK. I KEPT SLIGHT CHANCE POPS
LIMITED TO THE NORTH...TRANSITIONING TO THE WEST DURING THESE
PERIODS WITH SPRINKLES/FLURRIES ELSEWHERE.
WAA ASSOCIATED WITH SOUTHERLY FLOW WILL STILL SUPPORT HIGHS QUICKLY
WARMING AT LEAST IN CLOUD FREE AREAS TO THE 50S BEFORE TEMPERATURES
FALL THIS AFTERNOON BEHIND THE FRONT. LOWS TONIGHT WILL VARY BASED
ON TIMING OF WINDS DECREASING (AND SNOW PACK) AND WITH COLD CANADIAN
AIR MASS IN PLACE LOWS AROUND 10F WILL BE POSSIBLE...AND THE
POTENTIAL FOR SINGLE DIGIT LOW TEMPERATURES EXISTS IN THE WEST.
WHERE WINDS REMAIN HIGHER OVERNIGHT LOWS SHOULD BE CLOSER TO 20F.
AS WAS THE CASE YESTERDAY MODELS SHOW A STRONG PRESSURE GRADIENT
SUPPORTIVE OF AT LEAST NW WINDS GUSTING TO AROUND 40 MPH BASED ON
MIXING HEIGHTS. I STILL CANT RULE OUT SHOWERS MIXING A FEW STRONGER
GUSTS AND IF THIS CORRELATES WITH SNOW COULD REDUCE VISIBILITIES. I
DECIDED NOT TO ADD MENTION OF BLOWING SNOW TO THE GRIDS AND THE
THREAT IS VERY UNCERTAIN/ISOLATED. WILL STILL MAINTAIN MENTION IN
THE HWO.
SATURDAY-SUNDAY NIGHT...ZONAL FLOW AND A DEEP DRY AIR MASS RETURN AND
DRY CONDITIONS WILL PERSIST THROUGH THIS WEEKEND. SHALLOW/COLD AIR
MASS WILL REMAIN IN PLACE THROUGH THE DAY SATURDAY AND HIGHS WILL
GENERALLY BE IN THE 30S (NEAR FREEZING IN PROXIMITY OF SNOW FIELD).
A FEW LOCATIONS IN THE WEST COULD WARM TO AROUND 40 DEPENDING ON
MIXING. WITH INCREASING DOWNSLOPE FLOW/BUILDING LEE TROUGH WAA
INCREASES SUNDAY AND HIGHS IN THE 50S ARE EXPECTED IN AREAS WITHOUT
SNOW PACK. LOWS WILL REFLECT THE GRADUAL WARMING TREND...THOUGH WITH
GOOD RADIATION CONDITIONS/LOWER TD SATURDAY NIGHT WE SHOULD SEE LOWS
IN THE TEENS DESPITE MODERATION ALOFT.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 203 AM MST FRI NOV 20 2015
DRY AND WARM CONDITIONS ARE EXPECTED ON MONDAY AND TUESDAY AS AN
UPPER LEVEL RIDGE FLATTENS OUT ACROSS THE PLAINS AND ZONAL FLOW
DEVELOPS OVER THE REGION. A SHORTWAVE DOES LOOK TO MOVE THROUGH THE
FLOW ON TUESDAY...BUT KEPT THAT PERIOD DRY SINCE LIMITED MOISTURE
SHOULD INHIBIT PRECIP.
QUIET WEATHER PERSISTS FOR THE FORECAST AREA INTO WEDNESDAY AS
RIDGING DEVELOPS AHEAD OF THE NEXT LOW PRESSURE SYSTEM. THIS LOW
TRAVELS FROM THE NORTHWESTERN CONUS TOWARDS THE PLAINS MIDWEEK. A
STRONG COLD FRONT ASSOCIATED WITH THE SYSTEM IS CURRENTLY
ANTICIPATED TO PUSH ACROSS THE HIGH PLAINS WEDNESDAY
NIGHT/THURSDAY...GENERATING RAIN/SNOW CHANCES FOR THE AREA. ONLY
LIGHT ACCUMULATIONS ARE FORECAST AT THIS TIME. LOOKING AHEAD...IT
DOES APPEAR THAT THE REGION WILL SEE BITTER COLD TEMPERATURES JUST
AFTER THE HOLIDAY AS A COLDER AIR MASS PUSHES SOUTH.
TEMPERATURES WILL TREND DOWNWARDS DURING THE EXTENDED PERIOD WITH
HIGHS IN THE 50S ON MONDAY AND TUESDAY COOLING INTO THE UPPER 40S TO
MID 50S FOR WEDNESDAY. THE AREA SHOULD START TO SEE A STEEPER
DECREASE IN TEMPERATURES TOWARDS THE END OF THE WORK WEEK AFTER THE
PASSAGE OF THE COLD FRONT...WITH HIGHS FORECAST IN THE UPPER 30S TO
MID 40S ON THURSDAY. LOWS ARE EXPECTED TO BE IN THE 20S TO LOW 30S
THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 423 AM MST FRI NOV 20 2015
AS COLD FRONT DROPS SOUTH ACROSS THE REGION THIS AFTERNOON CIGS
WILL BEGIN TO LOWER AND WINDS WILL SHIFT TO THE NORTH-NORTHWEST
AND INCREASE. PREVAILING WIND GUSTS 30-35 KFT ARE EXPECTED THIS
AFTERNOON DECREASING DURING THE EVENING HOURS. A FEW STRONGER
GUSTS WILL BE POSSIBLE. MVFR CIGS 2500-3000 KFT ARE SHOWN BY MOST
GUIDANCE BEHIND THIS FRONT IMPROVING LATER TONIGHT. THERE IS SOME
INDICATION OF CIGS DROPPING TO 1500 KFT...HOWEVER CONFIDENCE
WASN`T HIGH ENOUGH TO PREVAIL THIS CONDITION. A FEW RAIN OR SNOW
SHOWERS WILL ALSO BE POSSIBLE. AT THIS TIME VIRGA APPEAR TO BE
MORE LIKELY...AND COVERAGE APPEARS TO BE TOO LOW IN SHOWERS TO
INCLUDE VCSH GROUP DURING THIS UPDATE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...DR
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
508 AM CST FRI NOV 20 2015
...Updated Aviation discussion...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 131 AM CST FRI NOV 20 2015
Enjoy the warm day today because conditions change tomorrow. For today,
we will be in the warm sector and there should be some adiabatic compressional
warming ahead of an approaching strong cold front. The ongoing maximum
temperature grid looked on track, although did increase values up a
bit across the northern zones since the fropa and resultant caa has
slowed a bit. Calling for mainly 60s with a few 50s across west-central
Kansas. The front will traverse the region tonight and strong caa is
expected. A strong 850-700-hPa baroclinic zone is expected to pass through.
Models have backed off a bit on flurry potential, but still have some
flurries along and north of Highway 96, where this baroclinic zone
is most pronounced. Winds will increase significantly tonight and through
tomorrow morning (25-30 mph). These windy conditions and cold lows heading
into Saturday morning will create apparent temperature values in the
single digits. Conditions are not cold enough for wind chill advisory
criteria, however.
.LONG TERM...(Saturday THROUGH Thursday)
ISSUED AT 131 AM CST FRI NOV 20 2015
A raw day is expected for Saturday with highs mainly in the 30s. The
northerly winds will decrease in magnitude throughout the day as high
pressure builds in. It will still feel rather blustery and raw through
even with the winds decreasing. The cold conditions will not last long,
as downslope flow is expected Sunday. Highs should jump up back into
the 50s for the end of the weekend. The moderation of temperatures will
continue through the first half of next week as lee troughing and resultant
warm air advection prevails. Conditions may change by Thanksgiving as
a strong upper level disturbance begins to impact the region with low
level frontogenesis across the state. The net result is a chance for
precipitation (probably starting out as showers and may be transition
to snow showers as caa sets in). The superblend pops look fine for now.
Did make slight adjustments to temps as we were warmer than compared
to everyone else. In about a week from now, we might be back on the
cold side again and the ECMWF is showing this cold pattern continuing
outside of the long term domain.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Saturday MORNING)
ISSUED AT 507 AM CST FRI NOV 20 2015
VFR conditions are expected today given that BUFR soundings
indicated only mid and high level moisture will accompany a weak
upper level disturbance as it crosses the Central High Plains
early today. At the surface a cold front will move south across
southwest Kansas early this afternoon. Behind this front gusty
northwest winds will develop with sustain wind speeds of up to 25
knots possible late today and early tonight. At this time based on
the 06z NAM and latest RAP these gusty winds are expected to reach
GCK between 21z Thursday and 00z Friday. Gusty winds are expected
at HYS around 00z Friday and DDC between 00z and 03z Friday. In
addition to the gusty winds low level moisture will return with
MVFR ceilings becoming possible after sunset, especially in the
HYS area.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 61 24 39 20 / 10 10 0 0
GCK 59 21 37 19 / 10 10 0 0
EHA 64 21 36 21 / 0 10 0 0
LBL 62 23 39 22 / 0 10 0 0
HYS 56 22 37 20 / 10 10 0 0
P28 61 29 42 21 / 10 10 0 0
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Sugden
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
955 AM CST FRI NOV 20 2015
.UPDATE...
MAIN ADJUSTMENT TO THE PREVIOUS FORECAST WAS TO INCREASE WINDS IN
THE COASTAL WATERS AND NEAR THE COAST. OFFSHORE WINDS HAVE BEEN
RUNNING 15 TO 20 KTS AND SOUTH OF THE I10 CORRIDOR 10 TO 15 KTS
WITH LATEST HRRR AND RUC GUIDANCE INDICATING THAT THESE WIND
SPEEDS WILL PERSIST THROUGH THE AFTERNOON. REST OF THE FORECAST
REMAINS ON TRACK WITH HIGH TEMPERATURES IN THE LOW TO MID 70S.
&&
.PREV DISCUSSION...
DISCUSSION...
20/12Z TAF ISSUANCE.
AVIATION...
HIGH PRES RIDGING SOUTH ACRS LA IS KEEPING A DRY AIRMASS IN
PLACE...WITH NELY WINDS AROUND 5 KT. SKC EXPECTED TO PREVAIL
TODAY AS THE HIGH MOVES EAST...ALLOWING WINDS TO BECOME MORE
ESELY THIS AFTN. MOISTURE WILL BEGIN TO INCREASE TONIGHT...WITH A
BKN/OVC MID-LVL DECK DEVELOPING AS A COLD FRONT MOVES INTO THE
AREA. A FEW SHRA WILL BE POSSIBLE LATE TONIGHT...MAINLY NEAR BPT.
24
PREV DISCUSSION...
.FIRST FREEZE/FROST OF THE SEASON POSSIBLE SUNDAY NIGHT/MONDAY
MORNING...
DISCUSSION...
SURFACE HIGH PRESSURE CENTERED OVER THE MID MISSISSIPPI VALLEY IS
RIDGING DOWN INTO THE FORECAST AREA THIS EARLY MORNING. AGAIN
PROVIDING FAIR CONDITIONS...WITH TEMPERATURES NEAR THE DAILY
OVERNIGHT LOW NORMALS.
WATER VAPOR IMAGERY SHOWS A LARGE UPPER LEVEL LOW OVER EASTERN
CANADA...NORTH OF THE GREAT LAKES. A SHORT WAVE WAS ROTATING
AROUND THIS FEATURE MOVING DOWN INTO THE MOUNTAIN WEST.
THE SHORT WAVE WILL CONTINUE TO DIG DOWN TO THE SOUTHEAST TODAY
HELPING TO CARVE OUT AN UPPER LEVEL TROUGH OVER THE EASTERN U.S.
THIS WEEKEND...WITH UPPER LEVEL RIDGING NOTED OVER THE WESTERN
U.S. THE RESULT WILL BE A DEEPENING NORTHWEST FLOW ALOFT...THAT
WILL PUSH A STRONG CANADIAN COLD FRONT DOWN THROUGH THE REGION.
THE COLD FRONT LOOKS TO ARRIVE IN THE FORECAST AREA LATE SATURDAY
MORNING...AND ACROSS THE FORECAST AREA DURING THE AFTERNOON HOURS.
BEFORE THE FRONT ARRIVES...MID MISSISSIPPI SURFACE RIDGE WILL MOVE
OFF TO THE EAST TO THE MID ATLANTIC STATES...WITH A SURFACE LOW
DEVELOPING OVER THE CENTRAL PLAINS...EAST OF THE ROCKIES. THIS
WILL ALLOW FOR A BRIEF PERIOD OF SOUTHEAST WINDS AND RETURN FLOW
MOISTURE OFF THE GULF TO OCCUR.
MOISTURE PROFILES FROM THE 20/00Z GFS ARE CONSISTENT WITH PAST
RUNS...WITH A RELATIVELY DRIER SOLUTION (PWAT BETWEEN 1.10-1.25
INCHES...WHICH IS SLIGHTLY ABOVE NOVEMBER NORM...AND MEAN RH
60-70 PERCENT)...WHILE THE 20/00Z ECMWF IS ALSO NOW CLOSER TO THE
GFS WITH ITS MOISTURE PROFILE AHEAD OF THE FRONT...JUST A LITTLE
MORE MOIST (PWAT 1.30-1.40 INCH RANGE AND MEAN RH OVER 70
PERCENT.) THIS SEEMS REASONABLE...AS GULF AIR MASS WILL STILL BE
MODIFIED AND NO REAL GOOD LOW LEVEL JET TO BRING IN DEEPER GULF
MOISTURE LOCATED FURTHER TO THE SOUTH.SO THERE IS BETTER CONFIDENCE
WITH POP NUMBERS.
SCATTERED SHOWERS WILL FORM AHEAD OF THE FRONT LATE FRIDAY NIGHT
AND GRADUALLY TAPER OFF FROM NORTH TO SOUTH DURING SATURDAY
AFTERNOON. LOW END POPS TO THE NORTH AND HIGH END POPS TO THE
SOUTH LOOK GOOD. RAINFALL SHOULD MAINLY BE ON THE LIGHT SIDE WITH
MAYBE A FEW MODERATE CELLS. THE GUIDANCE IS ALSO IN BETTER
AGREEMENT WITH THE INSTABILITY DURING THIS EVENT...WITH DECENT
CAPE AND LI`S STAYING OVER THE COASTAL WATERS. THEREFORE...THE
ACTIVITY FOR LAND AREAS WILL LIKELY JUST BE RAIN SHOWERS. AREA
WIDE AVERAGE QPF DURING THE FRONTAL PASSAGE LOOK TO BE LESS THAN A
QUARTER OF INCH NORTH OF I-10...AND JUST ABOVE A QUARTER OF AN
INCH ALONG THE I-10 CORRIDOR TO THE COAST.
WITH THE DEEP NORTHWEST FLOW BEHIND THE COLD FRONT...AIR MASS WILL
BE ORIGINATING FROM CANADA...A MUCH COOLER AND DRIER CONTINENTAL
AIR MASS WILL OVER TAKE THE FORECAST AREA LATE SATURDAY AND HANG
AROUND INTO EARLY NEXT WEEK. PROGS SHOW THE DRYNESS OF THE AIR
MASS WITH PWATS BY SUNDAY UNDER A QUARTER OF AN INCH AND MEAN RH
UNDER 20 PERCENT. AIR TEMPERATURES WILL BE SOME 15F DEGREES BELOW
THE DAILY NORMS.
THE COLDEST TEMPERATURES LOOK TO OCCUR ON SUNDAY NIGHT INTO MONDAY
MORNING WITH THE SURFACE HIGH SETTLING IN OVER THE FORECAST AREA.
THE LIGHT WINDS AND CLEAR SKIES SHOULD MAKE FOR GOOD RADIATIONAL
COOLING. THE LATEST OPERATION GFS MOS NUMBERS STILL ON THE LOW END
OF THE ENSEMBLE BY A FEW DEGREES. THE LOWS THAT WERE FORECAST BY
THE DAY SHIFT FOR MONDAY MORNING ARE VERY CLOSE TO BOTH THE LATEST
GFS MEAN AND THE ECMWF 50P AND 90P VALUES. THEREFORE...THOSE
NUMBERS LOOK REASONABLE TO GO WITH AGAIN. THIS MEANS THE FIRST
FREEZE/FROST OF THE SEASON LOOKS LIKE A GOOD BET FOR A PORTION OF
THE FORECAST AREA. A LIGHT FREEZE SEEMS REASONABLE FOR MOST OF
UPPER SOUTHEAST TEXAS AND CENTRAL LOUISIANA...WITH A FROST
POSSIBLE DOWN TO THE I-10 CORRIDOR DURING LATE SUNDAY NIGHT INTO
EARLY MONDAY MORNING.
THE COLD HIGH PRESSURE SYSTEM WILL MOVE OFF TO THE EAST ON
TUESDAY...WITH A MORE SOUTHEAST FLOW DEVELOPING...THAT WILL HELP
MODERATE TEMPERATURES AND START A WARMING TREND...WITH
TEMPERATURES THEN ABOVE DAILY NORMS AS MID-WEEK TO THE
THANKSGIVING HOLIDAY ROLLS AROUND. MOISTURE WILL ALSO
INCREASE...AND WITH THE FORECAST AREA BETWEEN AN UPPER LEVEL
TROUGH OVER THE WEST AND SOUTHWEST U.S. AND UPPER LEVEL RIDGING
FROM THE SOUTHERN GULF ACROSS THE SOUTHEAST U.S. THERE WILL BE A
CHANCE OF SHOWERS STARTING ON WEDNESDAY THROUGH THE END OF THE
FORECAST PERIOD.
RUA
MARINE...
WEAK SURFACE HIGH CENTERED OVER THE MID MISSISSIPPI VALLEY IS
RIDGING DOWN INTO THE COASTAL WATERS AND HELPING TO PRODUCE
MODERATE NORTHEAST WINDS...JUST UNDER EXERCISE CAUTION CRITERIA.
THESE WINDS WILL BECOME MORE EASTERLY TODAY...AND THEN BRIEFLY
SOUTHEAST TONIGHT AS THE HIGH MOVES OFF TO THE EAST AND A COLD
FRONT APPROACHES FROM THE NORTH.
THIS FRONT WILL BRING DOWN A RATHER CHILLY CANADIAN AIR MASS. THE
COLD AIR ADVECTION GOING OVER RELATIVELY WARMER WATER...GULF OF
MEXICO SEA TEMPERATURES IN THE LOW TO MID 70S...SHOULD CREATE
DECENT MIXING TO BRING DOWN STRONG WINDS TO THE SURFACE. SMALL
CRAFT ADVISORY CONDITIONS LOOK LIKELY FROM LATE SATURDAY INTO
SUNDAY...WITH THE POSSIBILITY OF FREQUENT GUSTS TO GALE FORCE OVER
THE OUTER WATERS SATURDAY NIGHT INTO EARLY SUNDAY.
THE STRONG NORTHERLY FLOW COULD ALSO PRODUCE LOW WATER CONDITIONS
DURING THE PREDICTED LOW TIDE TIMES FROM LATE SATURDAY INTO
SUNDAY.
WINDS WILL BEGIN TO DECREASE ON MONDAY AS THE HIGH SETTLES OVER
THE REGION...AND LIGHT ONSHORE FLOW STARTING ON TUESDAY AS THE
HIGH MOVES OFF TO THE EAST. THE EAST TO SOUTHEAST WINDS WILL
INCREASE BY MID WEEK AS THE NEXT LOW PRESSURE SYSTEM BEGINS TO
DEVELOP OVER THE ROCKIES.
RUA
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 71 52 65 38 / 0 20 30 10
LCH 73 56 68 43 / 0 30 50 10
LFT 73 57 69 42 / 0 30 40 10
BPT 76 59 68 43 / 0 30 50 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
PUBLIC...26
AREA FORECAST DISCUSSION
NWS CARIBOU ME
917 AM EST FRI NOV 20 2015
.SYNOPSIS...
AN OCCLUDED FRONT WILL CROSS THE REGION TODAY THROUGH EARLY
TONIGHT WITH RAIN IN ADVANCE OF THE FRONT...THEN EXIT ACROSS THE
MARITIMES LATER TONIGHT. HIGH PRESSURE WILL BUILD ACROSS THE
REGION SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...LATEST RADAR REFLECTIVITY IMAGERY SHOWS AN AREA OF RAIN
ENCOMPASSING MUCH OF NORTHERN AND DOWN EAST MAINE AS OF LATE THIS
MORNING. THERE IS A RATHER SHARP BACK EDGE TO THE RAIN EVIDENT ON
RADAR AS WELL. THE LATEST HRRR SHOWS THE BACK EDGE OF THE RAIN WILL
CONTINUE TO PROGRESS FORM WEST TO EAST DURING THE COURSE OF TODAY.
THE RAIN WILL LINGER THE LONGEST ACROSS THE EASTERN MAINE/NEW
BRUNSWICK BORDER WHERE THE RAIN WILL LIKELY CONTINUE INTO THIS
EVENING. NO SIGNIFICANT CHANGES TO CURRENT FORECAST.
PREVIOUS DISCUSSION...
RAIN WILL OCCUR ACROSS THE REGION TODAY IN ADVANCE OF AN OCCLUDED
FRONT MOVING EAST ACROSS THE FORECAST AREA. A STRONG LOW LEVEL JET
WILL ALSO CROSS THE REGION ON ADVANCE OF THE FRONT PRODUCING GUSTY
WINDS. THE STRONGEST WINDS ARE EXPECTED ALONG THE DOWNEAST COAST
WHERE ONSHORE WINDS COULD GUST TO AROUND 40 MPH AT TIMES. THE
FRONT WILL EXIT ACROSS NEW BRUNSWICK EARLY TONIGHT. RAIN WILL
TAPER TO SHOWERS IN THE WAKE OF THE FRONT EARLY TONIGHT BEFORE
ENDING. COLDER AIR IN THE WAKE OF THE FRONT COULD ALLOW RAIN
SHOWERS TO MIX WITH...OR CHANGE TO...SNOW SHOWERS ACROSS NORTHERN
MAINE EARLY TONIGHT WITH ANY SNOW ACCUMULATION LESS THAN AN INCH.
HIGH PRESSURE WILL THEN BUILD ACROSS THE REGION LATER TONIGHT WITH
DECREASING CLOUDS. HIGH TEMPERATURES TODAY WILL RANGE FROM THE MID
TO UPPER 40S NORTH...TO THE LOWER 50S DOWNEAST. LOW TEMPERATURES
TONIGHT WILL RANGE FROM THE MID TO UPPER 20S NORTH...TO AROUND 30
TO THE LOWER 30S DOWNEAST.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BUILD OVER THE REGION SATURDAY THEN MOVE TO
THE EAST SATURDAY NIGHT AS INTENSE LOW PRESSURE MOVES NORTHEAST
ACROSS QUEBEC PROVINCE. A COLD FRONT IS THEN EXPECTED TO MOVE
ACROSS THE STATE SUNDAY BEHIND THE LOW PRESSURE SYSTEM TO THE
NORTH. SHOWERS AND SNOW SHOWERS ARE EXPECTED EARLY SUNDAY IN THE
WEST AS THE FRONT APPROACHES THEN SHOWERS ARE EXPECTED LATER IN
THE DAY SUNDAY OVER THE REMAINDER OF THE REGION AS THE FRONT MOVES
THROUGH.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A COLDER AIR MASS WILL MOVE IN BEHIND THE FRONT SUNDAY NIGHT
ALONG WITH HIGH PRESSURE. A LOW PRESSURE SYSTEM IS ALSO EXPECTED
TO DEVELOP OFF THE EAST COAST SOUTH OF NEW ENGLAND SUNDAY NIGHT.
THIS SYSTEM WILL THEN MOVE NORTHWARD OVER THE OCEAN AND ACROSS
NOVA SCOTIA MONDAY AND MONDAY NIGHT. A STRONG HIGH PRESSURE SYSTEM
IS THEN EXPECTED TO BUILD ACROSS THE NORTHEAST TUESDAY AND
WEDNESDAY THEN MOVE TO THE EAST THURSDAY.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: IFR/LIFR CONDITIONS ARE EXPECTED ACROSS THE REGION
TODAY ALONG WITH GUSTY WINDS. MVFR/IFR CONDITIONS ARE EXPECTED
ACROSS THE REGION EARLY TONIGHT...THEN IMPROVING TO VFR LEVELS
OVERNIGHT.
SHORT TERM: EXPECT VFR CONDITIONS SATURDAY. MVFR CONDITIONS ARE
POSSIBLE SUNDAY AS A FRONTAL SYSTEM MOVES THROUGH AND STALLS EAST
OF THE AREA SUNDAY NIGHT. VFR CONDITIONS ARE EXPECTED MONDAY AND
TUESDAY.
&&
.MARINE...
NEAR TERM: A GALE WARNING REMAINS IN EFFECT FOR THE WATERS THROUGH
THIS AFTERNOON. SMALL CRAFT ADVISORY CONDITIONS ARE THEN EXPECTED
TONIGHT. VISIBILITIES WILL BE REDUCED IN RAIN AND FOG TODAY INTO
THIS EVENING.
SHORT TERM: HAVE USED A 50/50 BLEND OF THE NAM12 AND GFS40 FOR
SUSTAINED WINDS SATURDAY INTO SUNDAY THEN TRANSITION TO THE SUPER
BLEND WINDS. FOR WAVES: LONG PERIOD SOUTHEASTERLY WAVES FROM
PREVIOUS DAYS FETCH ARE EXPECTED TO SUBSIDE TO BELOW 2 FEET BY
SATURDAY MORNING. EXPECT PRIMARY WAVE SYSTEM SATURDAY TO BE
NORTHEASTERLY WIND WAVES. A NEW SOUTHEASTERLY FETCH IS THEN
EXPECTED TO DEVELOP OFF-SHORE AHEAD OF A DEVELOPING OCEAN LOW
SATURDAY NIGHT INTO SUNDAY. THIS WILL RESULT IN WAVE HEIGHTS
BUILDING TO AROUND 5 FEET/8 SECONDS ON SUNDAY. THIS WAVE SYSTEM
WILL ALSO PREDOMINATE ON MONDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...GALE WARNING UNTIL 5 PM EST THIS AFTERNOON FOR ANZ050>052.
&&
$$
NEAR TERM...DUDA/NORCROSS
SHORT TERM...MIGNONE
LONG TERM...MIGNONE
AVIATION...DUDA/NORCROSS/MIGNONE
MARINE...DUDA/NORCROSS/MIGNONE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
637 AM EST FRI NOV 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM EST FRI NOV 20 2015
AN UPPER TROUGH OVER ONTARIO IS LEADING TO THE COLDEST AIR THAT WE
HAVE SEEN THIS FALL...WITH 850MB TEMPS -12C AT KINL AT 00Z AND THAT
MATCHES THE RAP ANALYSIS OVER WESTERN LAKE SUPERIOR. A SECONDARY
TROUGH ASSOCIATED WITH THE STRONG LOW OVER HUDSON BAY IS SLOWLY
MOVING EAST ACROSS CENTRAL LAKE SUPERIOR AT THIS TIME AND HAS
SHIFTED WINDS MORE TO THE WEST OVER WESTERN LAKE SUPERIOR. THE COLD
TEMPS HAVE LED TO LAKE EFFECT SNOW IN THE WESTERLY WIND SNOW BELTS.
LOOKING AT WEBCAMS...IT IS TOUGH TO GET A HANDLE ON THE AMOUNT OF
SNOW THAT HAS FALLEN DUE TO THE STRONG WINDS...BUT IT LOOKS TO HAVE
PRODUCED A FEW INCHES IN THE HOUGHTON/CALUMET AREA. THE WINDS HAVE
HELPED CONTRIBUTE TO VISIBILITIES FALLING TO OR BELOW A MILE AT
TIMES AS THEY CONTINUE TO GUST TO 35-40KTS IN THE KEWEENAW.
EXPECT THE LAKE EFFECT TO CONTINUE THROUGH THE SHORT TERM
PERIOD...BUT THE INTENSITY SHOULD BE ON THE DECREASE DUE TO SEVERAL
FACTORS. FIRST...THE DEEP MOISTURE DIMINISHES AS AN UPPER RIDGE
MOVES OVER THE AREA TODAY AHEAD OF A SECONDARY TROUGH MOVING THROUGH
THE NORTHERN ROCKIES. SUBSIDENCE ALOFT WITH THAT RIDGING WILL HELP
LOWER INVERSION HEIGHTS THROUGH THE DAY TOWARDS 7-8KFT (FROM THE
PRESENT 10KFT). SECOND...THE INCREASED CONVERGENCE SEEN ALONG AND
JUST BEHIND THE SURFACE TROUGH WILL DIMINISH THROUGH THE MORNING
HOURS AS THE WINDS BECOME FAIRLY UNIFORM AROUND 270-280 DEGREES.
THERE IS A SECONDARY TROUGH THAT WILL MOVE THROUGH LATE THIS
AFTERNOON AND EARLY THIS EVENING...AND SHIFT WINDS AROUND TO MORE
290-300 DEGREES. THAT WILL BRING MORE LOCATIONS IN THE WESTERN AND
EASTERN U.P. UNDER SOME LAKE EFFECT SNOW (TRADITIONAL NW WIND SNOW
BELTS). ONE OTHER LIMITING FACTOR WILL BE THE CONTINUED INDICATION
BY THE MODELS OF AN INVERTED-V LOOK TO THE LOW LEVELS. THAT BEING
SAID...THE WEAKENING WINDS WILL INCREASE RESIDENCE TIME AND LEAD TO
LESS FRACTURING OF THE FLAKES FOR TONIGHT...SO WOULDN/T BE SURPRISED
TO SEE A FEW LOCATIONS PICKING UP ONE TO LOCALLY TWO INCHES AS MUCH
OF THE CLOUD WILL BE WITHIN THE DGZ. FOR TODAY...EXPECT DAYTIME
ACCUMULATIONS OF 1-2 INCHES OVER THE KEWEENAW AND MAYBE A TOUCH MORE
OVER FAR NORTHEAST LUCE COUNTY WHERE THE LONGER FETCH WILL CREATE
STRONGER BANDS THAT WILL SHIFT SOUTH ALONG THE LUCE COUNTY SHORELINE
IN THE AFTERNOON. AT THIS POINT...THE 15Z END TIME TO THE WINTER WX
ADVISORY LOOKS PRETTY GOOD AS THAT MATCHES UP WELL WITH THE
DIMINISHING TREND IN BOTH THE WINDS AND DEEPER MOISTURE.
WHILE WINDS ARE STILL GUSTING TO 40KTS OVER PORTIONS OF LAKE
SUPERIOR AND THE KEWEENAW PENINSULA AS OF 3AM...THE WEAKENING
PRESSURE GRADIENT THROUGH THE DAY WILL LEAD TO STEADILY DIMINISHING
WINDS THROUGH THE DAY AND EXPECT THEM TO FALL BELOW GALES OVER LAKE
SUPERIOR BY EARLY EVENING. THAT DIMINISHING WILL CONTINUE THROUGH
THE NIGHT AS THEY SHIFT TO THE NORTHWEST. FINALLY...HIGHS TODAY WILL
RANGE FROM THE UPPER 20S OVER THE WEST TO THE LOWER 30S OVER THE
EAST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 525 AM EST FRI NOV 20 2015
AFTER WARM WEATHER SO FAR THIS NOV ACROSS THE UPPER LAKES (AT NWS
MARQUETTE, IT`S BEEN THE WARMEST FIRST 19 DAYS OF NOV ON RECORD)...
SEASONABLY COLD WEATHER WILL BE THE RULE THRU THIS WEEKEND AS A TROF
DOMINATES THE GREAT LAKES REGION. NEXT WEEK...A BUILDING
RIDGE/POSITIVE HEIGHT ANOMALY IN THE GULF OF ALASKA INTO WRN CANADA
WILL FORCE TROFFING INTO THE WRN CONUS...THOUGH THE FLOW WILL BE
SPLIT AND TROF WILL BE POSITIVE TILT. THIS IN TURN WILL FORCE
DOWNSTREAM HEIGHT RISES FROM THE ERN PLAINS TO THE E COAST...
RESULTING IN WARMING FOR THE UPPER LAKES TUE/WED AND PERHAPS THRU
THANKSGIVING DAY. THE BIG UNCERTAINTY THAT MAY IMPACT HOLIDAY TRAVEL
IS HOW QUICKLY THE NRN PORTION OF THE WRN TROF PROGRESSES EASTWARD.
WITH THE SRN STREAM PORTION OF THE TROF STILL HANGING BACK OVER THE
SW STATES/SRN ROCKIES...IT MAY SEND ENERGY NE ALONG THE COLD FRONT
MARKING THE LEADING EDGE OF ARCTIC AIR BEING DRIVEN SE BY THE
POSITIVE HEIGHT ANOMALY IN WRN CANADA...RESULTING IN A BAND OF
WINTRY PCPN SOMEWHERE OVER THE UPPER MISSISSIPPI VALLEY OR WRN GREAT
LAKES LATE WEEK. SEASONABLY COLD WEATHER WILL FOLLOW INTO NEXT
WEEKEND...BUT TONIGHTS 00Z GFS/ECMWF ARE QUICKER PUSHING THE WRN
CANADA POSITIVE HEIGHT ANOMALY EASTWARD...WHICH CUTS OFF THE ARCTIC
AIR BEFORE IT REACHES THE UPPER LAKES. FARTHER OUT...CANADIAN
ENSEMBLES AND THE CFSV2 16 MEMBER ENSEMBLE MEAN FAVOR A RETURN TO
PACIFIC FLOW ACROSS THE NRN CONUS/SRN CANADA. SO...AT THIS
POINT...IT APPEARS AN ABOVE NORMAL TEMP REGIME WILL PROBABALY LOCK
IN AGAIN AFTER THE FIRST FEW DAYS OF DEC. AS FOR PCPN...ONGOING LES
WILL PICK UP SOME SAT AS ENERGY SWINGS SE INTO CNTRL PLAINS THEN NE
INTO THE ERN GREAT LAKES. SYSTEM WILL TRACK FAR ENOUGH S AND SE OF
HERE THAT THE SYNOPTIC SNOW SHIELD SHOULD PASS MOSTLY SE OF THE FCST
AREA. A CLIPPER TYPE SHORTWAVE WILL BRING SOME -SN SUN NIGHT/MON
WITH LAKE ENHANCEMENT OFF LAKE MI POSSIBLE INTO THE FAR ERN FCST
AREA. AFTER A TREND TO DRY WEATHER ON TUE...PCPN WILL RETURN
POSSIBLY AS EARLY AS WED AND CONTINUE INTO FRI.
BEGINNING SAT...SHORTWAVE SWINGING THRU THE PLAINS FRI NIGHT WILL
BEGIN TO SPIN UP A SFC WAVE THAT SHOULD BE IN THE VCNTY OF WRN IL AT
12Z SAT. AS THE SHORTWAVE LIFTS TOWARD THE ERN GREAT LAKES...THE LOW
WILL DEEPEN AND TRACK TO THE VCNTY OF DETROIT BY SAT EVENING. THE
REGIONAL CANADIAN AND NCEP ARW/NMM ARE THE DEEPEST/FARTHEST W
SOLUTIONS AND ARE NEARLY IDENTICAL WITH A TRACK TO NEAR SAGINAW BAY.
THE GFS IS A LITTLE FARTHER SE AND THE NAM/ECMWF ARE
WEAKEST/FARTHEST SE WITH A TRACK TO FAR WRN LAKE ERIE. THE CANADIAN
HAS TRENDED NW/STRONGER SINCE THE 12Z RUN...BUT IT IS WITHIN THE
ENVELOP OF THE LAST 5 SOLUTIONS. THE GFS HAS BEEN VERY CONSISTENT IN
THE LAST 5 RUNS. SINCE THE RELATIVELY WARM WATERS OF THE GREAT LAKES
OFTEN CAN HELP PULL DEVELOPING LOW PRES SYSTEMS TO THE W...
ESPECIALLY EARLY IN THE COLD SEASON...FCST WILL LEAN TOWARD THE
FARTHEST W SOLUTIONS OF THE REGIONAL GEM AND NCEP ARW/NMM. THESE
SOLUTIONS RESULT IN LOW-LEVEL FLOW BACKING MORE AND BECOMING MORE
CYCLONIC ACROSS UPPER MI/LAKE SUPERIOR WITH A PERIOD OF NW TO N FLOW
INCREASING LES COVERAGE OVER NRN UPPER MI. RESULT COULD BE THE
POTENTIAL FOR MDT SNOW ACCUMULATIONS OVER MUCH OF THE NCNTRL AND WRN
FCST AREA. THE NE FRINGE OF THE SYNOPTIC SNOW WOULD ALSO BRUSH THE
SE FCST AREA. WITH FCST SOUNDINGS SHOWING DEEPENING MOISTURE AND
FAIRLY HIGH SNOW TO WATER RATIOS...MAY SEE ADVY TYPE SNOWFALL FOR
THE NW TO N WIND FAVORED SNOWBELTS WITH THE MAIN TIME FRAME FOR THE
HEAVIER SNOW ROUGHLY IN THE 18Z SAT TO 06Z SUN TIME PERIOD. OFFICIAL
FCST WILL SHOW 12HR SNOW AMOUNTS OF 2-4 INCHES WHICH IS JUST UNDER
ADVY THRESHOLD FOR LES/HIGH SNOW TO WATER RATIO SNOW. NRN FRINGE OF
SYNOPTIC SNOW SHOULD ONLY YIELD AN INCH OR LESS ACROSS THE SCNTRL/SE
FCST AREA.
BACKING WINDS/DRYING AIR MASS AS HIGH PRES RIDGE ARRIVES SUN WILL
DIMINISH LINGERING LES. IN FACT...EXPECT ALL LES TO END BY LATE
AFTN AS WINDS BACK.
SUN NIGHT/MON...ATTENTION TURNS TO A CLIPPER TYPE SHORTWAVE THAT
REACHES THE UPPER GREAT LAKES MON MORNING. WAA/ISENTROPIC ASCENT
SHOULD YIELD SOME -SN SPREADING ACROSS THE AREA SUN NIGHT WITH
ACCUMULATIONS PROBABLY UNDER 1 INCH. OF MORE CONCERN IS THE BACKING
WINDS WHICH MAY BACK ENOUGH TO LEAD TO LAKE ENHANCEMENT OFF LAKE
MICHIGAN INTO THE FAR ERN FCST AREA SUN NIGHT. FOR NOW...INCREASED
POPS GENERALLY ALONG E OF KISQ/KERY LINE WITH A COUPLE OF INCHES OF
SNOW POSSIBLE.
SOME LIGHT WNW FLOW LES WILL BE POSSIBLE BEHIND THE SHORTWAVE INTO
MON NIGHT. DRY WEATHER WILL RETURN TUE UNDER WAA/BACKING WINDS.
AS ALLUDED TO ABOVE...THE BIG UNCERTAINTY LATER NEXT WEEK WILL BE
HOW QUICKLY THE NRN PORTION OF THE WRN TROF PROGRESSES EASTWARD.
WITH THE SRN STREAM PORTION OF THE TROF HANGING BACK OVER THE SW
STATES/SRN ROCKIES...THERE WILL BE THE POTENTIAL FOR A DECENT PCPN
EVENT ALONG THE COLD FRONT MOVING INTO THE GREAT LAKES. AT THIS
POINT...RECENT GFS/ECMWF RUNS SUGGEST RAIN DEVELOPING LATE WED INTO
THANKSGIVING DAY WITH A TRANSITION TO SNOW FROM NW TO SE
THANKSGIVING NIGHT/FRI. IT REMAINS TO BE SEEN WHETHER THIS WILL
DEVELOP INTO A SIGNIFICANT PCPN EVENT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 636 AM EST FRI NOV 20 2015
LAKE EFFECT SNOW SHOWERS WILL CONTINUE AT KCMX THROUGH THE PERIOD
BUT SHOULD SEE SOME DECREASE IN INTENSITY THROUGH THE DAY TODAY
WHICH WHEN COMBINED WITH WEAKENING WINDS SHOULD PUSH VISIBILITIES
UP. STILL EXPECT CONDITIONS TO BE IN THE MVFR RANGE WHEN THE SNOW
BANDS ARE AFFECTING THE SITE AFTER THE IFR CONDITIONS THIS MORNING.
AT KIWD...EXPECT BORDERLINE MVFR/VFR CONDITIONS FOR A PERIOD THIS
MORNING BASED ON UPSTREAM OBS...THEN TREND TO VFR AROUND MID DAY.
AS WINDS TURN MORE FAVORABLE FOR LAKE EFFECT THROUGH THE EVENING
HOURS...EXPECT CEILINGS AND VISIBILITIES TO TREND BACK DOWN TO
MVFR. FINALLY FOR KSAW...DOWNSLOPING WESTERLY WINDS TODAY AND
NORTHWEST TONIGHT WILL KEEP VFR CONDITIONS IN PLACE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 322 AM EST FRI NOV 20 2015
A TROUGH ASSOCIATED WITH A STRONG LOW PRESSURE SYSTEM OVER HUDSON
BAY WILL CROSS LAKE SUPERIOR THIS EVENING. OVER-WATER INSTABILITY
COMBINED WITH A STRONG PRESSURE GRADIENT WILL RESULT IN WSW STORM
FORCE WINDS TO 50 KNOTS FOR MUCH OF THE OPEN WATERS OF WEST AND
CENTRAL LAKE SUPERIOR THIS EVENING. ONCE THE TROUGH COMPLETELY
CROSSES THE LAKE OVERNIGHT...WINDS WILL SHIFT TO THE WEST AND GUST
TO GALES TO 35-40 KTS THROUGH MUCH OF FRIDAY. THESE STRONG WINDS
WILL DIMINISH STEADILY TO UNDER 25 KTS ON FRI NIGHT/SAT WITH THE
APPROACH OF A WEAK HI PRESSURE RIDGE. A STRONGER N TO NW FLOW UP TO
30 KTS IS POSSIBLE ON SAT NIGHT DEPENDING ON THE TRACK OF A LO PRES
MOVING NE THRU SE ONTARIO. THE FLOW WILL THEN SHIFT TO THE SW UP TO
25 KTS BY LATE SUN INTO MON AS A TRAILING HI PRES RIDGE CROSSES THE
UPPER LAKES AND AHEAD OF ANOTHER LO PRES TROUGH APPROACHING FROM THE
NW. FOLLOWING THE TROF PASSAGE...EXPECT W TO NW WINDS UP TO 25 KTS
ON MON INTO TUE...BUT THEN WINDS WILL SHIFT BACK TO THE SW BY
LATER ON TUE AFTER TRAILING HI PRES SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR MIZ001-
003.
LAKESHORE FLOOD ADVISORY UNTIL 10 AM EST THIS MORNING FOR MIZ001-
003.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ248>251-264>267.
GALE WARNING UNTIL 5 PM EST /4 PM CST/ THIS AFTERNOON FOR
LSZ241>245.
GALE WARNING UNTIL 1 PM EST /NOON CST/ THIS AFTERNOON FOR LSZ162-
240-246-247.
GALE WARNING UNTIL 4 PM EST THIS AFTERNOON FOR LSZ263.
LAKE MICHIGAN...
GALE WARNING UNTIL 10 AM EST THIS MORNING FOR LMZ221-248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
527 AM EST FRI NOV 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM EST FRI NOV 20 2015
AN UPPER TROUGH OVER ONTARIO IS LEADING TO THE COLDEST AIR THAT WE
HAVE SEEN THIS FALL...WITH 850MB TEMPS -12C AT KINL AT 00Z AND THAT
MATCHES THE RAP ANALYSIS OVER WESTERN LAKE SUPERIOR. A SECONDARY
TROUGH ASSOCIATED WITH THE STRONG LOW OVER HUDSON BAY IS SLOWLY
MOVING EAST ACROSS CENTRAL LAKE SUPERIOR AT THIS TIME AND HAS
SHIFTED WINDS MORE TO THE WEST OVER WESTERN LAKE SUPERIOR. THE COLD
TEMPS HAVE LED TO LAKE EFFECT SNOW IN THE WESTERLY WIND SNOW BELTS.
LOOKING AT WEBCAMS...IT IS TOUGH TO GET A HANDLE ON THE AMOUNT OF
SNOW THAT HAS FALLEN DUE TO THE STRONG WINDS...BUT IT LOOKS TO HAVE
PRODUCED A FEW INCHES IN THE HOUGHTON/CALUMET AREA. THE WINDS HAVE
HELPED CONTRIBUTE TO VISIBILITIES FALLING TO OR BELOW A MILE AT
TIMES AS THEY CONTINUE TO GUST TO 35-40KTS IN THE KEWEENAW.
EXPECT THE LAKE EFFECT TO CONTINUE THROUGH THE SHORT TERM
PERIOD...BUT THE INTENSITY SHOULD BE ON THE DECREASE DUE TO SEVERAL
FACTORS. FIRST...THE DEEP MOISTURE DIMINISHES AS AN UPPER RIDGE
MOVES OVER THE AREA TODAY AHEAD OF A SECONDARY TROUGH MOVING THROUGH
THE NORTHERN ROCKIES. SUBSIDENCE ALOFT WITH THAT RIDGING WILL HELP
LOWER INVERSION HEIGHTS THROUGH THE DAY TOWARDS 7-8KFT (FROM THE
PRESENT 10KFT). SECOND...THE INCREASED CONVERGENCE SEEN ALONG AND
JUST BEHIND THE SURFACE TROUGH WILL DIMINISH THROUGH THE MORNING
HOURS AS THE WINDS BECOME FAIRLY UNIFORM AROUND 270-280 DEGREES.
THERE IS A SECONDARY TROUGH THAT WILL MOVE THROUGH LATE THIS
AFTERNOON AND EARLY THIS EVENING...AND SHIFT WINDS AROUND TO MORE
290-300 DEGREES. THAT WILL BRING MORE LOCATIONS IN THE WESTERN AND
EASTERN U.P. UNDER SOME LAKE EFFECT SNOW (TRADITIONAL NW WIND SNOW
BELTS). ONE OTHER LIMITING FACTOR WILL BE THE CONTINUED INDICATION
BY THE MODELS OF AN INVERTED-V LOOK TO THE LOW LEVELS. THAT BEING
SAID...THE WEAKENING WINDS WILL INCREASE RESIDENCE TIME AND LEAD TO
LESS FRACTURING OF THE FLAKES FOR TONIGHT...SO WOULDN/T BE SURPRISED
TO SEE A FEW LOCATIONS PICKING UP ONE TO LOCALLY TWO INCHES AS MUCH
OF THE CLOUD WILL BE WITHIN THE DGZ. FOR TODAY...EXPECT DAYTIME
ACCUMULATIONS OF 1-2 INCHES OVER THE KEWEENAW AND MAYBE A TOUCH MORE
OVER FAR NORTHEAST LUCE COUNTY WHERE THE LONGER FETCH WILL CREATE
STRONGER BANDS THAT WILL SHIFT SOUTH ALONG THE LUCE COUNTY SHORELINE
IN THE AFTERNOON. AT THIS POINT...THE 15Z END TIME TO THE WINTER WX
ADVISORY LOOKS PRETTY GOOD AS THAT MATCHES UP WELL WITH THE
DIMINISHING TREND IN BOTH THE WINDS AND DEEPER MOISTURE.
WHILE WINDS ARE STILL GUSTING TO 40KTS OVER PORTIONS OF LAKE
SUPERIOR AND THE KEWEENAW PENINSULA AS OF 3AM...THE WEAKENING
PRESSURE GRADIENT THROUGH THE DAY WILL LEAD TO STEADILY DIMINISHING
WINDS THROUGH THE DAY AND EXPECT THEM TO FALL BELOW GALES OVER LAKE
SUPERIOR BY EARLY EVENING. THAT DIMINISHING WILL CONTINUE THROUGH
THE NIGHT AS THEY SHIFT TO THE NORTHWEST. FINALLY...HIGHS TODAY WILL
RANGE FROM THE UPPER 20S OVER THE WEST TO THE LOWER 30S OVER THE
EAST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 525 AM EST FRI NOV 20 2015
AFTER WARM WEATHER SO FAR THIS NOV ACROSS THE UPPER LAKES (AT NWS
MARQUETTE, IT`S BEEN THE WARMEST FIRST 19 DAYS OF NOV ON RECORD)...
SEASONABLY COLD WEATHER WILL BE THE RULE THRU THIS WEEKEND AS A TROF
DOMINATES THE GREAT LAKES REGION. NEXT WEEK...A BUILDING
RIDGE/POSITIVE HEIGHT ANOMALY IN THE GULF OF ALASKA INTO WRN CANADA
WILL FORCE TROFFING INTO THE WRN CONUS...THOUGH THE FLOW WILL BE
SPLIT AND TROF WILL BE POSITIVE TILT. THIS IN TURN WILL FORCE
DOWNSTREAM HEIGHT RISES FROM THE ERN PLAINS TO THE E COAST...
RESULTING IN WARMING FOR THE UPPER LAKES TUE/WED AND PERHAPS THRU
THANKSGIVING DAY. THE BIG UNCERTAINTY THAT MAY IMPACT HOLIDAY TRAVEL
IS HOW QUICKLY THE NRN PORTION OF THE WRN TROF PROGRESSES EASTWARD.
WITH THE SRN STREAM PORTION OF THE TROF STILL HANGING BACK OVER THE
SW STATES/SRN ROCKIES...IT MAY SEND ENERGY NE ALONG THE COLD FRONT
MARKING THE LEADING EDGE OF ARCTIC AIR BEING DRIVEN SE BY THE
POSITIVE HEIGHT ANOMALY IN WRN CANADA...RESULTING IN A BAND OF
WINTRY PCPN SOMEWHERE OVER THE UPPER MISSISSIPPI VALLEY OR WRN GREAT
LAKES LATE WEEK. SEASONABLY COLD WEATHER WILL FOLLOW INTO NEXT
WEEKEND...BUT TONIGHTS 00Z GFS/ECMWF ARE QUICKER PUSHING THE WRN
CANADA POSITIVE HEIGHT ANOMALY EASTWARD...WHICH CUTS OFF THE ARCTIC
AIR BEFORE IT REACHES THE UPPER LAKES. FARTHER OUT...CANADIAN
ENSEMBLES AND THE CFSV2 16 MEMBER ENSEMBLE MEAN FAVOR A RETURN TO
PACIFIC FLOW ACROSS THE NRN CONUS/SRN CANADA. SO...AT THIS
POINT...IT APPEARS AN ABOVE NORMAL TEMP REGIME WILL PROBABALY LOCK
IN AGAIN AFTER THE FIRST FEW DAYS OF DEC. AS FOR PCPN...ONGOING LES
WILL PICK UP SOME SAT AS ENERGY SWINGS SE INTO CNTRL PLAINS THEN NE
INTO THE ERN GREAT LAKES. SYSTEM WILL TRACK FAR ENOUGH S AND SE OF
HERE THAT THE SYNOPTIC SNOW SHIELD SHOULD PASS MOSTLY SE OF THE FCST
AREA. A CLIPPER TYPE SHORTWAVE WILL BRING SOME -SN SUN NIGHT/MON
WITH LAKE ENHANCEMENT OFF LAKE MI POSSIBLE INTO THE FAR ERN FCST
AREA. AFTER A TREND TO DRY WEATHER ON TUE...PCPN WILL RETURN
POSSIBLY AS EARLY AS WED AND CONTINUE INTO FRI.
BEGINNING SAT...SHORTWAVE SWINGING THRU THE PLAINS FRI NIGHT WILL
BEGIN TO SPIN UP A SFC WAVE THAT SHOULD BE IN THE VCNTY OF WRN IL AT
12Z SAT. AS THE SHORTWAVE LIFTS TOWARD THE ERN GREAT LAKES...THE LOW
WILL DEEPEN AND TRACK TO THE VCNTY OF DETROIT BY SAT EVENING. THE
REGIONAL CANADIAN AND NCEP ARW/NMM ARE THE DEEPEST/FARTHEST W
SOLUTIONS AND ARE NEARLY IDENTICAL WITH A TRACK TO NEAR SAGINAW BAY.
THE GFS IS A LITTLE FARTHER SE AND THE NAM/ECMWF ARE
WEAKEST/FARTHEST SE WITH A TRACK TO FAR WRN LAKE ERIE. THE CANADIAN
HAS TRENDED NW/STRONGER SINCE THE 12Z RUN...BUT IT IS WITHIN THE
ENVELOP OF THE LAST 5 SOLUTIONS. THE GFS HAS BEEN VERY CONSISTENT IN
THE LAST 5 RUNS. SINCE THE RELATIVELY WARM WATERS OF THE GREAT LAKES
OFTEN CAN HELP PULL DEVELOPING LOW PRES SYSTEMS TO THE W...
ESPECIALLY EARLY IN THE COLD SEASON...FCST WILL LEAN TOWARD THE
FARTHEST W SOLUTIONS OF THE REGIONAL GEM AND NCEP ARW/NMM. THESE
SOLUTIONS RESULT IN LOW-LEVEL FLOW BACKING MORE AND BECOMING MORE
CYCLONIC ACROSS UPPER MI/LAKE SUPERIOR WITH A PERIOD OF NW TO N FLOW
INCREASING LES COVERAGE OVER NRN UPPER MI. RESULT COULD BE THE
POTENTIAL FOR MDT SNOW ACCUMULATIONS OVER MUCH OF THE NCNTRL AND WRN
FCST AREA. THE NE FRINGE OF THE SYNOPTIC SNOW WOULD ALSO BRUSH THE
SE FCST AREA. WITH FCST SOUNDINGS SHOWING DEEPENING MOISTURE AND
FAIRLY HIGH SNOW TO WATER RATIOS...MAY SEE ADVY TYPE SNOWFALL FOR
THE NW TO N WIND FAVORED SNOWBELTS WITH THE MAIN TIME FRAME FOR THE
HEAVIER SNOW ROUGHLY IN THE 18Z SAT TO 06Z SUN TIME PERIOD. OFFICIAL
FCST WILL SHOW 12HR SNOW AMOUNTS OF 2-4 INCHES WHICH IS JUST UNDER
ADVY THRESHOLD FOR LES/HIGH SNOW TO WATER RATIO SNOW. NRN FRINGE OF
SYNOPTIC SNOW SHOULD ONLY YIELD AN INCH OR LESS ACROSS THE SCNTRL/SE
FCST AREA.
BACKING WINDS/DRYING AIR MASS AS HIGH PRES RIDGE ARRIVES SUN WILL
DIMINISH LINGERING LES. IN FACT...EXPECT ALL LES TO END BY LATE
AFTN AS WINDS BACK.
SUN NIGHT/MON...ATTENTION TURNS TO A CLIPPER TYPE SHORTWAVE THAT
REACHES THE UPPER GREAT LAKES MON MORNING. WAA/ISENTROPIC ASCENT
SHOULD YIELD SOME -SN SPREADING ACROSS THE AREA SUN NIGHT WITH
ACCUMULATIONS PROBABLY UNDER 1 INCH. OF MORE CONCERN IS THE BACKING
WINDS WHICH MAY BACK ENOUGH TO LEAD TO LAKE ENHANCEMENT OFF LAKE
MICHIGAN INTO THE FAR ERN FCST AREA SUN NIGHT. FOR NOW...INCREASED
POPS GENERALLY ALONG E OF KISQ/KERY LINE WITH A COUPLE OF INCHES OF
SNOW POSSIBLE.
SOME LIGHT WNW FLOW LES WILL BE POSSIBLE BEHIND THE SHORTWAVE INTO
MON NIGHT. DRY WEATHER WILL RETURN TUE UNDER WAA/BACKING WINDS.
AS ALLUDED TO ABOVE...THE BIG UNCERTAINTY LATER NEXT WEEK WILL BE
HOW QUICKLY THE NRN PORTION OF THE WRN TROF PROGRESSES EASTWARD.
WITH THE SRN STREAM PORTION OF THE TROF HANGING BACK OVER THE SW
STATES/SRN ROCKIES...THERE WILL BE THE POTENTIAL FOR A DECENT PCPN
EVENT ALONG THE COLD FRONT MOVING INTO THE GREAT LAKES. AT THIS
POINT...RECENT GFS/ECMWF RUNS SUGGEST RAIN DEVELOPING LATE WED INTO
THANKSGIVING DAY WITH A TRANSITION TO SNOW FROM NW TO SE
THANKSGIVING NIGHT/FRI. IT REMAINS TO BE SEEN WHETHER THIS WILL
DEVELOP INTO A SIGNIFICANT PCPN EVENT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1231 AM EST FRI NOV 20 2015
WINDY CONDITIONS WILL CONTINUE AT ALL SITES THROUGH TONIGHT BEFORE
GRADUALLY DIMINISHING THROUGH THE DAY FRIDAY. WESTERLY GUSTS AS HIGH
AS 40 KTS ARE EXPECTED AT CMX THAT WILL TAPER OFF SLIGHTLY
OVERNIGHT. CMX THROUGHTHIS EVENING...WHILE GUSTS OF 25-305 KNOTS ARE
EXPECTED FOR IWD AND SAW.
HEAVIER LAKE EFFECT SNOW BANDS ARE FORECAST TO FOCUS ACROSS THE
KEWEENAW PENINSULA OVERNIGHT. THIS COMBINED WITH THE GUSTY WINDS
WILL LIKELY BRING IFR TO POSSIBLY LIFR VIS TO CMX VSBY WITH MAINLY
MVFR CIGS THROUGH MUCH OF THE NIGHT. VSBY WILL IMPROVE TO MVFR BY
FRI AFTERNOON AS DRIER AIR MOVES INTO THE REGION. AT IWD AND
SAW...HIGH-END MVFR TO LOW-END VFR CIGS AND ISOLATED TO SCATTERED -
SHSN ARE FORECAST THROUGH THE PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 322 AM EST FRI NOV 20 2015
A TROUGH ASSOCIATED WITH A STRONG LOW PRESSURE SYSTEM OVER HUDSON
BAY WILL CROSS LAKE SUPERIOR THIS EVENING. OVER-WATER INSTABILITY
COMBINED WITH A STRONG PRESSURE GRADIENT WILL RESULT IN WSW STORM
FORCE WINDS TO 50 KNOTS FOR MUCH OF THE OPEN WATERS OF WEST AND
CENTRAL LAKE SUPERIOR THIS EVENING. ONCE THE TROUGH COMPLETELY
CROSSES THE LAKE OVERNIGHT...WINDS WILL SHIFT TO THE WEST AND GUST
TO GALES TO 35-40 KTS THROUGH MUCH OF FRIDAY. THESE STRONG WINDS
WILL DIMINISH STEADILY TO UNDER 25 KTS ON FRI NIGHT/SAT WITH THE
APPROACH OF A WEAK HI PRESSURE RIDGE. A STRONGER N TO NW FLOW UP TO
30 KTS IS POSSIBLE ON SAT NIGHT DEPENDING ON THE TRACK OF A LO PRES
MOVING NE THRU SE ONTARIO. THE FLOW WILL THEN SHIFT TO THE SW UP TO
25 KTS BY LATE SUN INTO MON AS A TRAILING HI PRES RIDGE CROSSES THE
UPPER LAKES AND AHEAD OF ANOTHER LO PRES TROUGH APPROACHING FROM THE
NW. FOLLOWING THE TROF PASSAGE...EXPECT W TO NW WINDS UP TO 25 KTS
ON MON INTO TUE...BUT THEN WINDS WILL SHIFT BACK TO THE SW BY
LATER ON TUE AFTER TRAILING HI PRES SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR MIZ001-
003.
LAKESHORE FLOOD ADVISORY UNTIL 10 AM EST THIS MORNING FOR MIZ001-
003.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ248>251-264>267.
GALE WARNING UNTIL 5 PM EST /4 PM CST/ THIS AFTERNOON FOR
LSZ241>245.
GALE WARNING UNTIL 1 PM EST /NOON CST/ THIS AFTERNOON FOR LSZ162-
240-246-247.
GALE WARNING UNTIL 4 PM EST THIS AFTERNOON FOR LSZ263.
LAKE MICHIGAN...
GALE WARNING UNTIL 10 AM EST THIS MORNING FOR LMZ221-248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...JLB
MARINE...SRF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
559 AM CST FRI NOV 20 2015
.UPDATED FOR 12Z AVIATION DISCUSSION...
ISSUED AT 548 AM CST FRI NOV 20 2015
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM CST FRI NOV 20 2015
WINTER STORM REMAINS ON TRACK TO BRING MODERATE TO HEAVY SNOW ACROSS
NORTHERN IOWA TODAY. THE NORTHERN EDGE OF THIS BAND SHOULD CLIP FAR
SOUTHERN MINNESOTA WITH UP TO 4 INCHES...SO HAVE ISSUED A WINTER
WEATHER ADVISORY BEING THE FIRST SNOWFALL OF THE SEASON. THE SNOW
WILL QUICKLY END TONIGHT...SETTING THE STAGE FOR THE COLDEST NIGHT
OF THE SEASON WITH LOWS IN THE MID TEENS TO LOWER 20S.
THE MODELS HAVE COME INTO BETTER AGREEMENT...AND WITH THE HIRES
SUITE STARTING TO CAPTURE THIS EVENT FEEL FAIRLY CONFIDENT WITH THE
SHORT TERM FORECAST. THE NCAR 10 MEMBER ENSEMBLE DEPICTS THE
UNCERTAINTY BEST...WITH SOME SOLUTIONS SHOWING HARDLY ANY PRECIP
ACROSS SOUTHERN MN...AND OTHERS SHOWING OVER A HALF TO THREE
QUARTERS OF AN INCH. WITH THE ADDITION OF THE HOPWRF AND HRRR FEEL
THAT SOUTHERN MN MAY GET 0.25 TO 0.40 INCHES OF LIQUID...EQUATING TO
2 TO 4 INCHES USING A BLEND OF THE GFS/NAM/AIR FORCE SNOW RATIOS
AT AROUND 10:1 TO 14:1.
A LATENT HEAT VS NON-LATENT HEAT MODEL COMPARISON SHOWS A SOUTHWARD
SHIFT IN THE TRACK FOR THE LATENT HEAT RUN...WHICH RESEMBLES REALITY
MUCH BETTER THAN THE NON-LATENT HEAT RUN...SO THAT IS ANOTHER VOTE
OF CONFIDENCE THAT THE WARNING CRITERIA SNOWFALL WILL STAY TO THE
SOUTH OF THE FORECAST AREA. LOOKING AHEAD...COLD AIR ADVECTION WILL
BRING A REINFORCEMENT OF SEASONABLY COOL AIR ACROSS THE REGION...AND
EXPECT LOW TEMPERATURE NEAR 20 TONIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 416 AM CST FRI NOV 20 2015
THE LONG TERM IS EXPECTED TO BE LARGELY QUIET UNTIL THE LAST HALF
OF NEXT WEEK...RIGHT IN TIME FOR THANKSGIVING AND BLACK FRIDAY. IN
FACT...IT COULD BE QUITE A STORMY END TO THE MONTH.
COLD AND DRY AIR WILL FOLLOW IN THE WAKE OF THE DEPARTING
PLAINS/GREAT LAKES LOW SATURDAY. HIGHS WILL ONLY BE IN THE 20S.
INCREASING CLOUDS ARE EXPECTED LATE SATURDAY AND SATURDAY NIGHT AS
A REINFORCING TROUGH DIGS SOUTHEAST FROM THE CANADIAN ROCKIES.
THIS...IN COMBINATION WITH A BACKING SURFACE FLOW TO THE
SOUTHWEST SHOULD KEEP TEMPERATURES FROM DROPPING INTO THE SINGLE
DIGITS OR LOW TEENS...ASIDE FROM PERHAPS THE SNOWY AREAS ALONG
I-90 IF CLOUDS ARE DELAYED A BIT. DID RAISE LOWS A COUPLE DEGREES
IN MOST LOCATIONS BUT THEY MAY STILL BE TOO COLD.
MEANWHILE...AN UPPER JET STREAK WILL ROUND THE CREST OF THE
WESTERN RIDGE SATURDAY NIGHT. AN ACCOMPANYING LOW PRESSURE SYSTEM
POLEWARD THE JET WILL BEGIN DIVING SOUTHEAST TOWARD THE ARROWHEAD
OF MN SUNDAY EVENING WITH A WARM FRONT EXTENDING TO THE SOUTHEAST
ACROSS WESTERN WI. THERE MAY BE ENOUGH LIFT AND MOISTURE TO BRING
SOME LIGHT SNOW SUNDAY NIGHT NEAR AND EAST OF THE WARM FRONT.
ACCUMULATIONS WOULD BE MINIMAL AND THE REST OF THE CWA WOULD BE
DRY SLOTTED.
AS THAT SYSTEM PUSHES EAST...THE RIDGE WILL BUILD EASTWARD ACROSS
THE PLAINS EARLY NEXT WEEK. MILDER TEMPERATURES WILL RETURN...BUT
NOT TO THE DEGREE SEEN FOR MUCH OF THIS MONTH. MORE IMPORTANTLY...
A TROUGH WILL DIG DOWN THE WEST COAST AND A POTENT CLOSED UPPER
LOW WILL STALL OVER NEVADA AND UTAH FOR THE REST OF THE WEEK.
LATEST GUIDANCE IS IN DECENT AGREEMENT AND SUGGESTS THIS CLOSED
LOW WILL EVENTUALLY PHASE WITH THE POLAR JET ACROSS CANADA AND
RESULT IN A LARGE SCALE POSITIVELY TILTED TROUGH/REX
BLOCK...MAKING IT QUITE DIFFICULT TO FULLY EJECT THE ENERGY FROM
THE SOUTHWEST THROUGH THE END OF THE PERIOD. A LONG FEED FROM THE
TROPICAL PACIFIC WILL SET UP IN THE MID/UPPER LEVELS AND TRANSPORT
QUITE A BIT OF MOISTURE INTO THE PLAINS AND UPPER MIDWEST. STRONG
HIGH PRESSURE /1035-1045MB/ OVER THE NORTHERN ROCKIES WILL AT THE
SAME TIME FEED THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST WITH
COLD BOUNDARY LAYER AIR BEHIND THE QUASI-STATIONARY SURFACE
BOUNDARY. THE RESULT COULD BE A PROLONGED WINTRY MESS BEGINNING
WEDNESDAY NIGHT AND CONTINUING THROUGH THE REST OF THE WEEK. KEPT
THE GRIDS A SIMPLE RAIN/SNOW MIX AT THIS RANGE...BUT THERMAL
PROFILES OFF THE GFS AND ECMWF WOULD SUPPORT MORE OF A
SNOW/SLEET/FREEZING RAIN SCENARIO...AND GIVEN THE MOISTURE FEED
AVAILABLE...MAJOR IMPACTS COULD RESULT. STAY TUNED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 548 AM CST FRI NOV 20 2015
VFR CONDITIONS THROUGHOUT. SNOW WILL STAY SOUTH OF THE TAF SITES
TODAY. WINDS WILL BE RELATIVELY LIGHT TODAY...BUT SHOULD INCREASE
LATER TONIGHT WITH GUSTS IN THE MID TEENS POSSIBLE.
KMSP...
VFR CONDITIONS THROUGHOUT. SNOW WILL STAY SOUTH OF MSP TODAY.
WINDS WILL BE RELATIVELY LIGHT TODAY...BUT SHOULD INCREASE LATER
TONIGHT WITH NORTH NORTHWEST GUSTS IN THE MID TEENS EXPECTED.
/OUTLOOK FOR KMSP/
SAT...VFR. WIND NW AT 10G15KT
SUN...VFR. WIND SW AT 10G20KT.
MON...VFR. WIND WNW AT 10G15KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 3 AM CST
SATURDAY FOR MNZ091>093.
&&
$$
SHORT TERM...JRB
LONG TERM...BORGHOFF
AVIATION...JRB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
416 AM CST FRI NOV 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM CST FRI NOV 20 2015
WINTER STORM REMAINS ON TRACK TO BRING MODERATE TO HEAVY SNOW ACROSS
NORTHERN IOWA TODAY. THE NORTHERN EDGE OF THIS BAND SHOULD CLIP FAR
SOUTHERN MINNESOTA WITH UP TO 4 INCHES...SO HAVE ISSUED A WINTER
WEATHER ADVISORY BEING THE FIRST SNOWFALL OF THE SEASON. THE SNOW
WILL QUICKLY END TONIGHT...SETTING THE STAGE FOR THE COLDEST NIGHT
OF THE SEASON WITH LOWS IN THE MID TEENS TO LOWER 20S.
THE MODELS HAVE COME INTO BETTER AGREEMENT...AND WITH THE HIRES
SUITE STARTING TO CAPTURE THIS EVENT FEEL FAIRLY CONFIDENT WITH THE
SHORT TERM FORECAST. THE NCAR 10 MEMBER ENSEMBLE DEPICTS THE
UNCERTAINTY BEST...WITH SOME SOLUTIONS SHOWING HARDLY ANY PRECIP
ACROSS SOUTHERN MN...AND OTHERS SHOWING OVER A HALF TO THREE
QUARTERS OF AN INCH. WITH THE ADDITION OF THE HOPWRF AND HRRR FEEL
THAT SOUTHERN MN MAY GET 0.25 TO 0.40 INCHES OF LIQUID...EQUATING TO
2 TO 4 INCHES USING A BLEND OF THE GFS/NAM/AIR FORCE SNOW RATIOS
AT AROUND 10:1 TO 14:1.
A LATENT HEAT VS NON-LATENT HEAT MODEL COMPARISON SHOWS A SOUTHWARD
SHIFT IN THE TRACK FOR THE LATENT HEAT RUN...WHICH RESEMBLES REALITY
MUCH BETTER THAN THE NON-LATENT HEAT RUN...SO THAT IS ANOTHER VOTE
OF CONFIDENCE THAT THE WARNING CRITERIA SNOWFALL WILL STAY TO THE
SOUTH OF THE FORECAST AREA. LOOKING AHEAD...COLD AIR ADVECTION WILL
BRING A REINFORCEMENT OF SEASONABLY COOL AIR ACROSS THE REGION...AND
EXPECT LOW TEMPERATURE NEAR 20 TONIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 416 AM CST FRI NOV 20 2015
THE LONG TERM IS EXPECTED TO BE LARGELY QUIET UNTIL THE LAST HALF
OF NEXT WEEK...RIGHT IN TIME FOR THANKSGIVING AND BLACK FRIDAY. IN
FACT...IT COULD BE QUITE A STORMY END TO THE MONTH.
COLD AND DRY AIR WILL FOLLOW IN THE WAKE OF THE DEPARTING
PLAINS/GREAT LAKES LOW SATURDAY. HIGHS WILL ONLY BE IN THE 20S.
INCREASING CLOUDS ARE EXPECTED LATE SATURDAY AND SATURDAY NIGHT AS
A REINFORCING TROUGH DIGS SOUTHEAST FROM THE CANADIAN ROCKIES.
THIS...IN COMBINATION WITH A BACKING SURFACE FLOW TO THE
SOUTHWEST SHOULD KEEP TEMPERATURES FROM DROPPING INTO THE SINGLE
DIGITS OR LOW TEENS...ASIDE FROM PERHAPS THE SNOWY AREAS ALONG
I-90 IF CLOUDS ARE DELAYED A BIT. DID RAISE LOWS A COUPLE DEGREES
IN MOST LOCATIONS BUT THEY MAY STILL BE TOO COLD.
MEANWHILE...AN UPPER JET STREAK WILL ROUND THE CREST OF THE
WESTERN RIDGE SATURDAY NIGHT. AN ACCOMPANYING LOW PRESSURE SYSTEM
POLEWARD THE JET WILL BEGIN DIVING SOUTHEAST TOWARD THE ARROWHEAD
OF MN SUNDAY EVENING WITH A WARM FRONT EXTENDING TO THE SOUTHEAST
ACROSS WESTERN WI. THERE MAY BE ENOUGH LIFT AND MOISTURE TO BRING
SOME LIGHT SNOW SUNDAY NIGHT NEAR AND EAST OF THE WARM FRONT.
ACCUMULATIONS WOULD BE MINIMAL AND THE REST OF THE CWA WOULD BE
DRY SLOTTED.
AS THAT SYSTEM PUSHES EAST...THE RIDGE WILL BUILD EASTWARD ACROSS
THE PLAINS EARLY NEXT WEEK. MILDER TEMPERATURES WILL RETURN...BUT
NOT TO THE DEGREE SEEN FOR MUCH OF THIS MONTH. MORE IMPORTANTLY...
A TROUGH WILL DIG DOWN THE WEST COAST AND A POTENT CLOSED UPPER
LOW WILL STALL OVER NEVADA AND UTAH FOR THE REST OF THE WEEK.
LATEST GUIDANCE IS IN DECENT AGREEMENT AND SUGGESTS THIS CLOSED
LOW WILL EVENTUALLY PHASE WITH THE POLAR JET ACROSS CANADA AND
RESULT IN A LARGE SCALE POSITIVELY TILTED TROUGH/REX
BLOCK...MAKING IT QUITE DIFFICULT TO FULLY EJECT THE ENERGY FROM
THE SOUTHWEST THROUGH THE END OF THE PERIOD. A LONG FEED FROM THE
TROPICAL PACIFIC WILL SET UP IN THE MID/UPPER LEVELS AND TRANSPORT
QUITE A BIT OF MOISTURE INTO THE PLAINS AND UPPER MIDWEST. STRONG
HIGH PRESSURE /1035-1045MB/ OVER THE NORTHERN ROCKIES WILL AT THE
SAME TIME FEED THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST WITH
COLD BOUNDARY LAYER AIR BEHIND THE QUASI-STATIONARY SURFACE
BOUNDARY. THE RESULT COULD BE A PROLONGED WINTRY MESS BEGINNING
WEDNESDAY NIGHT AND CONTINUING THROUGH THE REST OF THE WEEK. KEPT
THE GRIDS A SIMPLE RAIN/SNOW MIX AT THIS RANGE...BUT THERMAL
PROFILES OFF THE GFS AND ECMWF WOULD SUPPORT MORE OF A
SNOW/SLEET/FREEZING RAIN SCENARIO...AND GIVEN THE MOISTURE FEED
AVAILABLE...MAJOR IMPACTS COULD RESULT. STAY TUNED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1210 AM CST FRI NOV 20 2015
VFR CONDITIONS THROUGHOUT. GUSTS SHOULD DECREASE OVERNIGHT...AND
MID LEVEL CLOUDS WILL MOVE IN DURING THE MORNING. SNOW IS EXPECTED
TO STAY SOUTH OF THE AIRPORTS.
KMSP...
VFR CONDITIONS THROUGHOUT. SNOW SHOULD STAY SOUTH OF MSP FRIDAY
EVENING.
/OUTLOOK FOR KMSP/
SAT...VFR. WIND NW 10-15 KTS.
SUN...VFR. WIND SW 10 KTS.
MON...VFR. WIND W 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 3 AM CST
SATURDAY FOR MNZ091>093.
&&
$$
SHORT TERM...JRB
LONG TERM...BORGHOFF
AVIATION...JRB
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
618 AM CST FRI NOV 20 2015
.SHORT TERM: (Through Saturday night)
Issued at 346 AM CST Fri Nov 20 2015
The primary forecast issues through Saturday are related to an
approaching low pressure system: extent of snowfall late tonight
and tomorrow morning, non-diurnal temperatures on Saturday,
strong winds on Saturday, and cold temperatures on Saturday
night.
The upper vort max which will become the focus for wx over the
next 36hrs was just entering ID/MT at 10z per water vapor imagery
and the RAP analysis of the 1.5 PVU sfc. The vort max dives
southeastward and induces surface cyclogenesis today/tonight, and
the resulting sfc low is then lifted northeastward through
MO/IL/IN in response to the approaching upper disturbance.
The surface low really needs to be farther south for even the
northern parts of the LSX CWA to see any appreciable snowfall.
Since no such southern shift has been observed, at best perhaps a
few to several tenths of an inch of snow might collect on grassy
areas in the far northern CWA after colder air on the back side
of the system deepens sufficiently to change light rain over to a
light rain/snow mix. The ground is still warm and no accumulation
is expected on roads. The best time period for any snowflakes is
after midnight on Fri night and before noon on Sat. No winter
headlines are anticipated attm.
Strong CAA on the back side of the aforementioned low pressure
system yields a non-diurnal temperature trend on Saturday. For
some locations, the daily high temperature might actually occur at
midnight. Strong northwest winds are also expected during the day
on Saturday across most of the area, although neither the
sustained winds nor the wind gusts look high enough for a wind
advisory attm (wind advisory criteria is sustained 30-39 mph for
1+ hours or gusts of 45-57 mph). Regardless, the combination of
falling temperatures, gusty northwest winds, and lingering rain
(possibly mixed with snowflakes) on Saturday won`t exactly make
for a Chamber of Commerce kind of day.
Winds should decrease quickly by late Saturday afternoon or early
Saturday evening. A surface high will be migrating across the
area on Saturday night, and some recent model runs now place the
ridge axis across the CWA at 12z Sun. This is significant because
the mostly clear skies and nearly calm winds could enhance
radiational cooling overnight in what is already a chilly air
mass. Overnight lows in the upper teens to lower 20s still look on
track.
A secondary vort max is still expected to move across the area on
Saturday night, but no additional precipitation is expected.
Depending on how much moisture is present aloft, however,
increased mid/high cloudiness associated with this feature could
interfere with the radiational cooling described above.
Kanofsky
.LONG TERM: (Sunday through Thursday)
Issued at 346 AM CST Fri Nov 20 2015
A strong vort max is forecast to dive out of Canada towards the
Great Lakes on Sunday night into Monday, but so far it appears
that the effects of this system will remain to the north and east
of the LSX CWA.
The models continue to show large disagreement for early next
week. Unlike 24hrs ago, the models now have a lead shortwave
zipping across the southern half of the country early in the week
before a much larger low pressure system organizes over the
western CONUS. There are also large differences between recent
runs and last night`s 00z runs with respect to the evolution of
the large low pressure system. The extended forecast generally
follows the recommended CR initialization due to low run-to-run
continuity and overall lack of model agreement.
Kanofsky
&&
.AVIATION: (For the 12z TAFs through 12z Saturday Morning)
Issued at 615 AM CST Fri Nov 20 2015
WAA/isentropic ascent will increase across the region as we head
into the afternoon and evening hours as storm system begins to
wind up over the Plains, and all of the guidance is suggesting a
similar "thickening and lowering" cloud trend as the day
progresses. In spite of the initially dry AMS have tried to be
fairly aggressive in bringing a rain threat into the area during
the mid/late afternoon hours because of the intensity of the warm
advection, and have roughly modeled start times on last few HRRR
runs, but ceilings with the onset of the rain should remain fairly
high...aoa 6kft.
Ceilings should continue to slowly drop overnight tonight as WAA
continues to lift and moisten the lower level AMS and generate
precip. Conceptually, with surface low tracking from mid-MO to
north of STL in the 06-12z time frame, ceilings will likely drop
to MVFR at KUIN, with the precip transitioning from rain to snow
sometime around 09z when freezing level finally begins to drop in
this part of the FA. Elsewhere in the "warm sector" of the system,
overnight ceilings are expected to remain in the 3-5kft range,
although expect a rapid drop in ceilings with FROPA at KCOU just
before daybreak.
Specifics for KSTL: A gradual increase in mid clouds is forecast
today. This increase in mid level moisture may produce a bit of
light rain by late in the day, but ceilings will remain above 8000
feet. As mentioned above, the very strong WAA that is progged
across the area tonight should cause the rain threat to ramp up
with a continued...gradual lowering of ceilings, but still expect
bases to remain above 3kft through at least 08z. However, passage
of strong cold front Saturday morning in the 12-15z time frame
will advect MVFR cigs into the area, along with strong northwest
winds that will eventually gust over 30 kts later on Saturday.
Truett
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
427 AM CST FRI NOV 20 2015
.SHORT TERM: (Through Saturday night)
Issued at 346 AM CST Fri Nov 20 2015
The primary forecast issues through Saturday are related to an
approaching low pressure system: extent of snowfall late tonight
and tomorrow morning, non-diurnal temperatures on Saturday,
strong winds on Saturday, and cold temperatures on Saturday
night.
The upper vort max which will become the focus for wx over the
next 36hrs was just entering ID/MT at 10z per water vapor imagery
and the RAP analysis of the 1.5 PVU sfc. The vort max dives
southeastward and induces surface cyclogenesis today/tonight, and
the resulting sfc low is then lifted northeastward through
MO/IL/IN in response to the approaching upper disturbance.
The surface low really needs to be farther south for even the
northern parts of the LSX CWA to see any appreciable snowfall.
Since no such southern shift has been observed, at best perhaps a
few to several tenths of an inch of snow might collect on grassy
areas in the far northern CWA after colder air on the back side
of the system deepens sufficiently to change light rain over to a
light rain/snow mix. The ground is still warm and no accumulation
is expected on roads. The best time period for any snowflakes is
after midnight on Fri night and before noon on Sat. No winter
headlines are anticipated attm.
Strong CAA on the back side of the aforementioned low pressure
system yields a non-diurnal temperature trend on Saturday. For
some locations, the daily high temperature might actually occur at
midnight. Strong northwest winds are also expected during the day
on Saturday across most of the area, although neither the
sustained winds nor the wind gusts look high enough for a wind
advisory attm (wind advisory criteria is sustained 30-39 mph for
1+ hours or gusts of 45-57 mph). Regardless, the combination of
falling temperatures, gusty northwest winds, and lingering rain
(possibly mixed with snowflakes) on Saturday won`t exactly make
for a Chamber of Commerce kind of day.
Winds should decrease quickly by late Saturday afternoon or early
Saturday evening. A surface high will be migrating across the
area on Saturday night, and some recent model runs now place the
ridge axis across the CWA at 12z Sun. This is significant because
the mostly clear skies and nearly calm winds could enhance
radiational cooling overnight in what is already a chilly air
mass. Overnight lows in the upper teens to lower 20s still look on
track.
A secondary vort max is still expected to move across the area on
Saturday night, but no additional precipitation is expected.
Depending on how much moisture is present aloft, however,
increased mid/high cloudiness associated with this feature could
interfere with the radiational cooling described above.
Kanofsky
.LONG TERM: (Sunday through Thursday)
Issued at 346 AM CST Fri Nov 20 2015
A strong vort max is forecast to dive out of Canada towards the
Great Lakes on Sunday night into Monday, but so far it appears
that the effects of this system will remain to the north and east
of the LSX CWA.
The models continue to show large disagreement for early next
week. Unlike 24hrs ago, the models now have a lead shortwave
zipping across the southern half of the country early in the week
before a much larger low pressure system organizes over the
western CONUS. There are also large differences between recent
runs and last night`s 00z runs with respect to the evolution of
the large low pressure system. The extended forecast generally
follows the recommended CR initialization due to low run-to-run
continuity and overall lack of model agreement.
Kanofsky
&&
.AVIATION: (For the 06z TAFs through 06z Friday Night)
Issued at 1145 PM CST Thu Nov 19 2015
VFR conditions will prevail at the TAF sites thru much of the
valid period. Look for clouds to increase later tonight with
gradually lowering CIGs thru the day on Friday, likely attaining
MVFR CIGs at UIN by 06z/Sat, and COU just beyond the end of the
valid period. Light rain should also rapidly close in on UIN and
COU heading towards sunset Friday evening with STL metro sites
being affected later that evening. In the meantime, look for
light surface winds becoming SE later tonight, then gusty at times
Friday, with a sharp veer and strengthening from the W-NW with
cold FROPA just beyond the valid period.
Specifics for KSTL: VFR thru much of the valid period with clouds
increasing late, then gradually lowering thru the day on Friday
and into the evening. Rain looks to be a bit faster moving in
during the evening but should be light when it does. Light winds
will become SE late tonight, then gusty towards midday Friday and
into the evening. Look for a sharp veer and strengthening from
the W-NW late Friday night with cold FROPA, along with
introduction of MVFR CIGs but should also signal and end to the
rain.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BISMARCK ND
949 AM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 943 AM CST FRI NOV 20 2015
MADE SOME MINOR ADJUSTMENTS TO SKY COVER AND POPS. OTHERWISE NO
SIGNIFICANT UPDATES TO THE GOING FORECAST. LATEST BOWMAN RADAR
INDICATES SOME LIGHT REFLECTIVITIES TRACKING SOUTHEAST ACROSS
BOWMAN/SLOPE COUNTIES...AND A BRIEF SNOW SHOWER INDICATED AT
BAKER MT SO WILL KEEP A MENTION OF SNOW IN THE FAR SOUTHWEST. THIS
WAS TRIMMED BACK EVEN MORE FROM OUR PREVIOUS FORECAST.
UPDATE ISSUED AT 630 AM CST FRI NOV 20 2015
NO CHANGES OF SIGNIFICANCE WERE MADE WITH THIS UPDATE AS WE ONLY
BLENDED CURRENT OBSERVATIONS WITH RECENT SHORT-RANGE MODEL OUTPUT.
WE HAVE RETAINED A LOW-END CHANCE OF LIGHT SNOW IN FAR SOUTHWEST
ND THROUGH EARLY AFTERNOON...BUT NEITHER UPSTREAM OBSERVATIONS IN
MT NOR RECENT HRRR SIMULATIONS ARE SUGGESTIVE OF MUCH POTENTIAL.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CST FRI NOV 20 2015
A WEAK HIGH PRESSURE RIDGE AXIS EXTENDED FROM SOUTHERN
SASKATCHEWAN SOUTHEASTWARD ACROSS NORTHWESTERN NORTH DAKOTA
THROUGH SOUTH CENTRAL NORTH DAKOTA. THIS RIDGE WAS BETWEEN A
STRONG LOW PRESSURE SYSTEM OVER HUDSON BAY AND ANOTHER LOW OVER
WYOMING. AT UPPER LEVELS...A DEEP UPPER LEVEL LOW WAS OVER HUDSON
BAY...WITH A SECONDARY TROUGH OVER THE NORTHERN ROCKIES AND FRONT
RANGE.
MID LEVEL CLOUD COVER ASSOCIATED WITH THE UPPER LEVEL TROUGH
EXTENDED FROM ALBERTA SOUTHEASTWARD TO SOUTH DAKOTA/NEBRASKA. THE
LOW OVER WYOMING AND UPPER LEVEL TROUGH WAS ASSOCIATED WITH LIGHT
SNOW AND LOWER CLOUDS MAINLY SOUTH AND WEST OF NORTH DAKOTA...BUT
ADDED A MENTION OF A SLIGHT CHANCE OF LIGHT SNOW IN THE FAR
SOUTHWEST THIS MORNING. BOWMAN RADAR INDICATING POSSIBLE LIGHT SNOW
REACHING THE GROUND WITH LIGHT RADAR RETURNS IN THE FAR
SOUTHWEST...MAINLY ALONG AND SOUTH OF HIGHWAY 12. OTHERWISE MID LEVEL
CLOUDS WERE OVER PARTS OF WESTERN AND CENTRAL NORTH DAKOTA...AND
WILL LIKELY CONTINUE TO BRING SOME PARTLY CLOUDY SKIES TO
NORTH DAKOTA. ALSO...A COLD FRONT MOVING SOUTHEAST OUT OF
SASKATCHEWAN IS EXPECTED TO ENTER NORTHWESTERN NORTH DAKOTA
BY DAYBREAK...WITH SOME LOWER LEVEL CLOUDS. THUS A PARTLY TO MOSTLY
CLOUDY DAY EXPECTED. ANOTHER COOL DAY WITH HIGHS FROM 20 TO 30.
ANOTHER COOL NIGHT TONIGHT AS WELL WITH PARTLY TO MOSTLY CLOUDY
SKIES. SOME WARM ADVECTION MAY BEGIN IN THE WEST LATE FRIDAY
NIGHT...BUT STILL EXPECT OVERNIGHT LOWS TO RANGE FROM 5 TO 15.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 AM CST FRI NOV 20 2015
HIGHLIGHTS IN THE LONG TERM INCLUDE GUSTY WINDS SUNDAY AND THE
POSSIBILITY OF WINTER WEATHER IMPACTING THANKSGIVING TRAVEL.
A FEW WEAK AND MOISTURE-STARVED IMPULSES EMBEDDED IN NORTHWEST
FLOW ALOFT WILL CROSS THE REGION THIS WEEKEND. THE 00 UTC MODEL
GUIDANCE CALLS FOR 850-MB WINDS OF 45 TO 55 KT DEVELOPING ACROSS
THE AREA SUNDAY INTO SUNDAY EVENING AS A WEAK CLIPPER-TYPE LOW
TRACKS ACROSS CENTRAL CANADA. THE EFFICIENCY OF MOMENTUM TRANSFER
IS IN QUESTION GIVEN A LACK OF ROBUST COLD AIR ADVECTION...SO WE
ARE NOT CONFIDENT IN HEADLINE-WORTHY GUSTS...BUT IT WILL LIKELY BE
A WINDY DAY REGARDLESS. A BRIEF WARM-UP IS STILL EXPECTED SUNDAY
INTO MONDAY WITH FORECAST HIGHS FROM THE MID 30S TO THE MID 40S F.
BY NEXT WEDNESDAY AND THURSDAY...A DEEP 500-MB LOW IS FORECAST TO
DIG INTO THE GREAT BASIN...AND THAT COULD YIELD SNOWFALL OVER THE
REGION. HOWEVER...THE 00 UTC MODEL SUITE GENERALLY TRENDED FURTHER
SOUTH WITH THE PRIMARY DYNAMIC FORCING THAT REACHES THE PLAINS AND
THUS IT SUGGESTED LOWER SNOWFALL TOTALS IN WESTERN AND CENTRAL ND
THAN PREVIOUS MODEL CYCLES. THUS...CONFIDENCE IN POSSIBLE IMPACTS
TO THANKSGIVING TRAVEL IS NOT VERY HIGH. A SEVEN MEMBER...TIME-
LAGGED ENSEMBLE OF DETERMINISTIC GFS RUNS ALSO YIELDED LESS THAN A
30 PERCENT PROBABILITY OF 0.10 INCHES OR MORE OF LIQUID-EQUIVALENT
PRECIPITATION WEDNESDAY THROUGH THANKSGIVING...FURTHER SUGGESTIVE
OF A LACK OF RUN-TO-RUN MODEL CONSENSUS ON DETAILS OF THE PATTERN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 943 AM CST FRI NOV 20 2015
SURFACE HIGH PRESSURE WAS OVER NORTH DAKOTA WITH LOW PRESSURE OVER
WYOMING AND LOW PRESSURE OVER HUDSON BAY. A TROUGH OF LOW PRESSURE
WILL SPREAD CLOUDS LOW VFR CONDITIONS INTO KISN AND KMOT AROUND
15Z AND SCT TO BKN CLOUDS AT KBIS/KDIK/KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JV
LONG TERM...CJS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
634 AM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 630 AM CST FRI NOV 20 2015
NO CHANGES OF SIGNIFICANCE WERE MADE WITH THIS UPDATE AS WE ONLY
BLENDED CURRENT OBSERVATIONS WITH RECENT SHORT-RANGE MODEL OUTPUT.
WE HAVE RETAINED A LOW-END CHANCE OF LIGHT SNOW IN FAR SOUTHWEST
ND THROUGH EARLY AFTERNOON...BUT NEITHER UPSTREAM OBSERVATIONS IN
MT NOR RECENT HRRR SIMULATIONS ARE SUGGESTIVE OF MUCH POTENTIAL.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CST FRI NOV 20 2015
A WEAK HIGH PRESSURE RIDGE AXIS EXTENDED FROM SOUTHERN
SASKATCHEWAN SOUTHEASTWARD ACROSS NORTHWESTERN NORTH DAKOTA
THROUGH SOUTH CENTRAL NORTH DAKOTA. THIS RIDGE WAS BETWEEN A
STRONG LOW PRESSURE SYSTEM OVER HUDSON BAY AND ANOTHER LOW OVER
WYOMING. AT UPPER LEVELS...A DEEP UPPER LEVEL LOW WAS OVER HUDSON
BAY...WITH A SECONDARY TROUGH OVER THE NORTHERN ROCKIES AND FRONT
RANGE.
MID LEVEL CLOUD COVER ASSOCIATED WITH THE UPPER LEVEL TROUGH
EXTENDED FROM ALBERTA SOUTHEASTWARD TO SOUTH DAKOTA/NEBRASKA. THE
LOW OVER WYOMING AND UPPER LEVEL TROUGH WAS ASSOCIATED WITH LIGHT
SNOW AND LOWER CLOUDS MAINLY SOUTH AND WEST OF NORTH DAKOTA...BUT
ADDED A MENTION OF A SLIGHT CHANCE OF LIGHT SNOW IN THE FAR
SOUTHWEST THIS MORNING. BOWMAN RADAR INDICATING POSSIBLE LIGHT SNOW
REACHING THE GROUND WITH LIGHT RADAR RETURNS IN THE FAR
SOUTHWEST...MAINLY ALONG AND SOUTH OF HIGHWAY 12. OTHERWISE MID LEVEL
CLOUDS WERE OVER PARTS OF WESTERN AND CENTRAL NORTH DAKOTA...AND
WILL LIKELY CONTINUE TO BRING SOME PARTLY CLOUDY SKIES TO
NORTH DAKOTA. ALSO...A COLD FRONT MOVING SOUTHEAST OUT OF
SASKATCHEWAN IS EXPECTED TO ENTER NORTHWESTERN NORTH DAKOTA
BY DAYBREAK...WITH SOME LOWER LEVEL CLOUDS. THUS A PARTLY TO MOSTLY
CLOUDY DAY EXPECTED. ANOTHER COOL DAY WITH HIGHS FROM 20 TO 30.
ANOTHER COOL NIGHT TONIGHT AS WELL WITH PARTLY TO MOSTLY CLOUDY
SKIES. SOME WARM ADVECTION MAY BEGIN IN THE WEST LATE FRIDAY
NIGHT...BUT STILL EXPECT OVERNIGHT LOWS TO RANGE FROM 5 TO 15.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 AM CST FRI NOV 20 2015
HIGHLIGHTS IN THE LONG TERM INCLUDE GUSTY WINDS SUNDAY AND THE
POSSIBILITY OF WINTER WEATHER IMPACTING THANKSGIVING TRAVEL.
A FEW WEAK AND MOISTURE-STARVED IMPULSES EMBEDDED IN NORTHWEST
FLOW ALOFT WILL CROSS THE REGION THIS WEEKEND. THE 00 UTC MODEL
GUIDANCE CALLS FOR 850-MB WINDS OF 45 TO 55 KT DEVELOPING ACROSS
THE AREA SUNDAY INTO SUNDAY EVENING AS A WEAK CLIPPER-TYPE LOW
TRACKS ACROSS CENTRAL CANADA. THE EFFICIENCY OF MOMENTUM TRANSFER
IS IN QUESTION GIVEN A LACK OF ROBUST COLD AIR ADVECTION...SO WE
ARE NOT CONFIDENT IN HEADLINE-WORTHY GUSTS...BUT IT WILL LIKELY BE
A WINDY DAY REGARDLESS. A BRIEF WARM-UP IS STILL EXPECTED SUNDAY
INTO MONDAY WITH FORECAST HIGHS FROM THE MID 30S TO THE MID 40S F.
BY NEXT WEDNESDAY AND THURSDAY...A DEEP 500-MB LOW IS FORECAST TO
DIG INTO THE GREAT BASIN...AND THAT COULD YIELD SNOWFALL OVER THE
REGION. HOWEVER...THE 00 UTC MODEL SUITE GENERALLY TRENDED FURTHER
SOUTH WITH THE PRIMARY DYNAMIC FORCING THAT REACHES THE PLAINS AND
THUS IT SUGGESTED LOWER SNOWFALL TOTALS IN WESTERN AND CENTRAL ND
THAN PREVIOUS MODEL CYCLES. THUS...CONFIDENCE IN POSSIBLE IMPACTS
TO THANKSGIVING TRAVEL IS NOT VERY HIGH. A SEVEN MEMBER...TIME-
LAGGED ENSEMBLE OF DETERMINISTIC GFS RUNS ALSO YIELDED LESS THAN A
30 PERCENT PROBABILITY OF 0.10 INCHES OR MORE OF LIQUID-EQUIVALENT
PRECIPITATION WEDNESDAY THROUGH THANKSGIVING...FURTHER SUGGESTIVE
OF A LACK OF RUN-TO-RUN MODEL CONSENSUS ON DETAILS OF THE PATTERN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 630 AM CST FRI NOV 20 2015
SURFACE HIGH PRESSURE WAS OVER NORTH DAKOTA WITH LOW PRESSURE OVER
WYOMING AND LOW PRESSURE OVER HUDSON BAY. A TROUGH OF LOW PRESSURE
WILL SPREAD CLOUDS AND MVFR TO LOW VFR CONDITIONS INTO KISN AND KMOT
AROUND 15Z AND SCT TO BKN CLOUDS AT KBIS/KDIK/KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...JV
LONG TERM...CJS
AVIATION...JV
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
513 AM CST FRI NOV 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CST FRI NOV 20 2015
PRESENT RADAR SHOWING DEVELOPING SNOW BAND FROM SOUTHWESTERN SOUTH
DAKOTA TO NORTH CENTRAL NEBRASKA VERY EARLY THIS MORNING...THOUGH
NOT SEEING ANY SNOW REACHING THE GROUND ON THE EASTERN EXTENT OF THE
BAND WITH DRY LOW LEVEL AIR IN PLACE. THIS AREA OF SNOW LOOKS TO BE
COLLOCATED WELL WITH MODEL 700 MB FRONTOGENESIS FIELDS. STILL LOOKING
AT A DECENT SNOW EVENT ACROSS THE AREA TODAY WITH STRENGTHENING MID
LEVEL FRONTOGENESIS AND UPPER LEVEL LIFT AIDED BY A JET STREAK
SITUATED THROUGH NORTHERN SOUTH DAKOTA INTO MINNESOTA. MODELS IN
FAIRLY DECENT AGREEMENT ON A STRONG FRONTOGENETIC BAND DEVELOPING
INTO SOUTH CENTRAL SOUTH DAKOTA IN THE EARLY MORNING...THEN
SPLITTING TO THE NORTH AND SOUTH BY LATE MORNING...WITH THE SOUTHERN
BAND BECOMING DOMINATE OVER NORTHWESTERN IOWA BY AFTERNOON AS
OPTIMUM 500-300 MB DIV Q SLIDES THROUGH SOUTHERN SOUTH DAKOTA AND
NEBRASKA DURING THAT TIME FRAME. THIS SCENARIO POINTS TO HEAVY SNOW
DEVELOPING SOUTH OF INTERSTATE 90 DURING THE DAY...WITH AMOUNTS
DECREASING RAPIDLY TO THE NORTH WHERE DRIER AIR WILL BE GREATER AND
FORCING IS LESS. WHAT IS SOMEWHAT DISTURBING IS THAT MOST RECENT
MODEL RUNS...INCLUDING THE RAP AND HRRR ARE TRENDING FARTHER TO THE
NORTH WITH THE MORNING PERIOD SNOWFALL IN THE INITIAL FRONTOGENETIC
BAND...PLACING IT RIGHT ALONG THE INTERSTATE 90 CORRIDOR...BEFORE
COLLAPSING IT SOUTHWARD BY AFTERNOON AS EXPLAINED ABOVE. IN
ADDITION...THEY ARE HINTING AT SOME INSTABILITY OF THE FRONT SO
THERE COULD BE A PERIOD OF HEAVIER SNOWFALL IN THIS VICINITY DURING
THE MORNING HOURS. STILL THINKING THE GENERAL HEAVIER SNOW WILL BE
SOUTH OF I90 FOR MOST OF THE DAY...BUT WILL BE SOMETHING TO KEEP AN
EYE ON. WINDS WILL REMAIN ON THE LIGHTER SIDE TODAY...SO BLOWING
SNOW SHOULD NOT BE AN ISSUE. REMAINED BELOW GUIDANCE WITH RESPECT TO
TEMPERATURES...WITH PRECIPITATION AND WET BULBING EFFECTS...SO
LOOKING AT HIGHS JUST EITHER SIDE OF 30 DEGREES. USING SNOW RATIOS
IN THE RANGE OF 11:1 TO 15:1 AND CURRENTLY PROJECTED TOTAL SNOWFALL
AMOUNTS RANGE FROM JUST UNDER AN INCH ALONG THE HIGHWAY 14
CORRIDOR...TO 4 TO 6 INCHES ALONG THE I90 CORRIDOR...TO 6 TO 9
INCHES SOUTH OF THAT AREA...TRENDING HIGHEST TOWARD NORTHWESTERN
IOWA. IN LIGHT OF ALL THE ABOVE REASONING...ISSUED A WINTER WEATHER
ADVISORY ONE STRIP OF COUNTIES FARTHER TO THE NORTH THAN PREVIOUS
FORECAST...ALONG THE I90 CORRIDOR...WITH A WINTER STORM WARNING FOR
AREAS TO THE SOUTH.
BY THIS EVENING THE MIDLEVEL FRONTOGENETIC FORCING SLIDES EASTWARD
INTO NORTH CENTRAL AND NORTHEASTERN IOWA WITH MAXIMUM UPPER LEVEL
DIV Q FOLLOWING SUIT. WITH THAT...WILL SEE SNOW TAPER OFF FROM WEST
TO EAST DURING THE EVENING. MAY GET SOME CLEARING LATER IN THE
NIGHT...AND WENT ON THE LOWER SIDE OF GUIDANCE...ESPECIALLY IN
EXPECTED SNOW COVERED AREAS...WITH OVERNIGHT READINGS IN THE MID
TEENS NORTH TO AROUND 10 SOUTH OF THE I90 CORRIDOR.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 354 AM CST FRI NOV 20 2015
A DRY FIRST HALF OF THE MEDIUM RANGE FORECAST...WITH MORE UNSETTLED
WEATHER TAKING AIM FOR THE THANKSGIVING HOLIDAY. EARLY ON THIS
WEEKEND...BEHIND TODAYS DEPARTING SNOWSTORM...THE MAIN CONCERN WILL
BE WITH TEMPERATURES. THE FIRST COLD DAY OF THE LATE FALL AND EARLY
WINTER SEASON WILL ARRIVE ON SATURDAY. FRESH SNOW COVER...COMBINED
WITH H850 MB TEMPERATURES -10 TO -14C WILL KEEP TEMPERATURES WELL
BELOW NORMAL THIS WEEKEND. SATURDAYS HIGHS MAY STRUGGLE TO BREAK
FREE FROM THE MID 20S. ON SUNDAY...WE WILL HAVE A RETURN OF
SOUTHWESTERLY BOUNDARY LAYER AND LOW LEVEL FLOW...BUT FRESH SNOW
COVER WILL AGAIN HAMPER TEMPERATURES SIGNIFICANTLY.
QUIET WEATHER THROUGH THE FIRST HALF OF NEXT WEEK AS RIDGING SPREADS
ACROSS THE CENTRAL UNITED STATES. WARM SOUTHERLY FLOW SHOULD BUMP
TEMPERATURES BACK INTO THE 40S AND SHOULD MELT SOME OF THE SNOWPACK.
THE CONCERN COULD THEN TURN TO FOG POTENTIAL IN THE MIDWEEK
TIMEFRAME.
WHILE STILL EARLY...WE WILL HAVE TO KEEP AN EYE ON A DEEP UPPER
THROUGH DIGGING INTO THE SOUTHWESTERN US THIS WEEK. THIS SYSTEM
COULD BRING MESSY WEATHER INTO THE MIDDLE OF THE COUNTRY FOR THE
THANKSGIVING HOLIDAY. MODELS SEEM TO AGREE THAT A COLD FRONT WILL
SURGE THROUGH THE REGION LATE WEDNESDAY INTO THURSDAY. CONSIDERABLE
UPPER LIFT MAY SPREAD ACROSS THE REGION WITH THE H850 BOUNDARY
LINGERING OVER THE COLDER SFC AIR. THIS SOLN COULD PRODUCE A MYRIAD
OF WINTRY WEATHER IN THE LOCAL AREA BY THANKSGIVING AND THE DAY
AFTER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 507 AM CST FRI NOV 20 2015
SNOW IS EXPECTED TO DEVELOP ACROSS THE AREA THIS
MORNING...WITH HEAVIEST SNOW FROM THE INTERSTATE 90 CORRIDOR AND
SOUTHWARD. SNOW WILL BE HEAVY AT TIMES THROUGH THE
AFTERNOON...WITH MVFR AND IFR CONDITIONS COMMON. AREAS ALONG THE
HIGHWAY 14 CORRIDOR...INCLUDING KHON...WILL BE EFFECTED LESS FROM
THE STORM SYSTEM...THUS CONDITIONS WILL RESIDE MAINLY IN THE VFR
TO UPPER END MVFR RANGE. SNOW WILL TAPER OFF THIS EVENING FROM
WEST TO EAST.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR SDZ063>071.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR SDZ050-
057>061.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR SDZ062.
MN...WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR MNZ089-090-098.
IA...WINTER STORM WARNING FROM 9 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR IAZ001>003-012-013-020.
WINTER STORM WARNING FROM 9 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR IAZ014-021-022-031-032.
NE...WINTER STORM WARNING FROM 9 AM THIS MORNING TO 9 PM CST THIS
EVENING FOR NEZ013-014.
&&
$$
SHORT TERM...JM
LONG TERM...DUX
AVIATION...JM
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1113 AM MST FRI NOV 20 2015
.UPDATE...
ISSUED AT 1113 AM MST FRI NOV 20 2015
SHORT TERM GUIDANCE AND HRRR SHOWING SOME GUSTY WINDS QUICKLY
DEVELOPING AROUND NOONTIME...SUPPORTED BY STRONG JET ALOFT...AS
THE SHORT WAVE MOVES DOWNSTREAM. BOOSTED GRIDDED WINDS TO REFLECT
THIS IDEA. WIND GUSTS TO 40 MPH WILL BE COMMON ACROSS THE NRN
VALLEYS AND ALONG THE I70 CORRIDO EAST OF GRAND JUNCTION. THIS IS
BELOW WIND ADVISORY CRITERIA AND NO PLANS TO ISSUE ONE.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 229 AM MST FRI NOV 20 2015
A FEW INCHES OF NEW SNOW FELL OVER THE NORTHERN MTNS AND AREAS OF
THE CENTRAL MTNS OVERNIGHT AS ONE JET STREAK MOVED OVERHEAD. THE
SECOND STREAK THAT IS PROGGED TO MOVE OVER THE SAME AREA FROM
ABOUT DAYBREAK THROUGH THE EVENING HOURS TODAY IS WHEN THE MOST
SNOW WILL FALL. IMPORTANT TO MENTION THAT MODELS HAVE PULLED BACK
ON SNOW AMOUNTS THROUGH THE DAY WITH THE GFS PULLING BACK THE
MOST. EVEN SO...HIGHLIGHTS IN PLACE LOOK GOOD BUT WILL NEED TO BE
MONITORED THROUGH THE DAY AS MODELS STILL DON`T AGREE THAT WELL.
AREAS AWAY FROM THE MTNS WILL SEE GENERALLY PARTLY CLOUDY SKIES
WITH NEAR NORMAL TEMPS IF NOT A LITTLE ABOVE. PRECIP WILL END BY
EARLY SATURDAY MORNING GIVING WAY TO MOSTLY SUNNY SKIES AS HIGH
PRESSURE BUILDS IN.
AS FAR AS TEMPS ARE CONCERNED...THICKNESS VALUES CONTINUE TO SHOW
TEMPS DROPPING AFTER THE CURRENT SYSTEM MOVES OFF TO THE EAST. NAM
GUIDANCE REALLY DROPS TEMPS...SINGLE DIGITS TO TEENS BY SATURDAY
MORNING...WHILE GFS NOT AS DRASTIC BUT STILL INDICATING TEMPS
MUCH COOLER THAN SEEN RECENTLY. EITHER WAY...A RATHER BRISK
SATURDAY IN STORE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 229 AM MST FRI NOV 20 2015
MID-RANGE MODELS AGREE THAT MONDAY AND TUESDAY WILL BRING PLEASANT
WEATHER AS HIGH PRESSURE REMAINS IN CONTROL WITH TEMPS WARMING UP
EACH DAY. BY WEDNESDAY MORNING...A CLOSED LOW WILL BE APPROACHING
THE AREA FROM THE NW CAUSING INCREASED CLOUD COVERAGE AND PRECIP
CHANCES FROM ABOUT NOON ONWARDS. THE LOCATION OF THE LOW PRESSURE
WILL SET UP TO THE WEST OF THE GREAT SALT LAKE IN UT AND STAY
THERE SPINNING FOR THE REST OF THE WEEK. THIS OCCURS AS UPPER
LEVEL SUPPORT GETS CUTOFF AND NO KICKER SHOWS ITSELF UNTIL THE
WEEKEND TO GET THE SYSTEM MOVING AGAIN. THE EC ALSO BITING OFF ON
THIS SOLN THOUGH DIFFERENCES SHOW UP FOR THE WEEKEND. PRECIP
CERTAINLY POSSIBLE FOR THE CWA BUT THE FINER DETAILS...HOW
MUCH...WHERE...HOW LONG...JUST NOT THERE YET. DOES LOOK MORE
LIKELY THAT THANKSGIVING WILL BE UNSETTLED THOUGH WITH COOLER THAN
AVERAGE TEMPERATURES. AS THIS SYSTEM IS A LONG WAYS OUT...PLENTY
OF CHANGES POSSIBLE OVER THE COMING DAYS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1113 AM MST FRI NOV 20 2015
THROUGH 02Z THIS EVENING...IFR/MVFR CIGS OR BELOW ILS BREAKPOINTS
WILL BE COMMON TODAY OVER THE NORTHERN AND CENTRAL COLORADO
MOUNTAINS. PERIODS OF SNOW IS EXPECTED IN THE HIGH COUNTRY...
ALTHOUGH LIGHT SNOW/RAIN MAY OCCUR AT KEGE OR KASE. MECHANICAL
TURBULENCE OVER THE MOUNTAINS IS EXPECTED.
IMPROVING CONDITIONS ARE EXPECTED AFTER 02Z WITH A CLEARING TREND
UNDERWAY. ALL MOUNTAIN SITES WILL HAVE VFR CONDITIONS AFTER 06Z.
VFR WILL BE MAINAINED FOR THE LOWER ELEVATIONS AND DESERT VALLEYS.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 6 PM MST THIS EVENING FOR COZ004-
010-013.
WINTER STORM WARNING UNTIL 6 PM MST THIS EVENING FOR COZ004.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...TGR
LONG TERM...TGR
AVIATION...PF
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1137 AM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 1129 AM CST FRI NOV 20 2015
VERY LIGHT SNOW HAS DEVELOPED IN BENTON COUNTY NEAR VINTON AND IS ALSO
BEING REPORTED IN METRO CEDAR RAPIDS. AS A RESULT THE OVERALL TIMING
OF PRECIPITATION HAS BEEN SPED UP.
THE EVAPORATIVE COOLING DUE TO THE STRONG FORCING IS ALLOWING
PRECIPITATION TO BE ALL SNOW ONCE IT REACHES THE GROUND. THIS SNOW
IS OCCURRING THE THE NARROW BAND ACROSS NORTHERN IOWA INTO EASTERN
IOWA PER RADAR. IMMEDIATE SHORT TERM TRENDS INDICATE THIS BAND
WILL SLOWLY LIFT TO THE EAST NORTHEAST THROUGH EARLY AFTERNOON. AS
THE SATURATION PROCESS BECOMES MORE EFFICIENT...PRECIPITATION IS
EXPECTED TO QUICKLY BREAK OUT ACROSS EASTERN IOWA FROM MID TO
LATE AFTERNOON.
&&
.SYNOPSIS...
ISSUED AT 328 AM CST FRI NOV 20 2015
CURRENT SATELLITE IMAGERY DEPICTS CLEAR SKIES TONIGHT AS HIGH
PRESSURE IS IN PLACE ACROSS THE REGION. AT THE SFC...DRY AIR IS IN
PLACE WITH DEWPOINTS IN THE LOW 20S TO UPPER TEENS. OVER THE FAR
NORTHERN CONUS ROCKY MOUNTAINS...AN UPPER LEVEL WAVE WAS MOVING SE
INTO THE HIGH PLAINS. THIS WAVE IS EXPECTED TO BRING OUR FIRST
WINTER STORM TO THE AREA LATER TODAY AND OVERNIGHT AND INTO SATURDAY
MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 328 AM CST FRI NOV 20 2015
MAIN FORECAST CONCERN FOR THE SHORT TERM IS THE IMPENDING WINTER
STORM TO AFFECT THE AREA TODAY AND TONIGHT. OVERALL FORECAST HAS
CHANGED LITTLE WITH THE MOST NOTABLE CHANGE WITH A SHIFT SOUTH OF
THE HEAVY SNOW AXIS. GUIDANCE SUGGESTS THAT PRECIP COULD START AS
EARLY AS 18Z ACROSS THE FAR NORTHERN ZONES. OVERALL NO CHANGES TO
THE CURRENT HEADLINES WERE MADE.
H5 WAVE IS FORECAST TO MOVE INTO THE CENTRAL PLAINS BY 18Z TODAY.
MODELS ARE CONSISTENT WITH THE PLACEMENT OF THE MAIN FORCING. THE
GFS IS THE FASTEST OF THE OPERATIONAL MODELS AND THIS SEEMS TO BE
SLIGHTLY SLOWER THAN THE GEFS ENSEMBLE MEAN. BETWEEN 00Z AND 12Z
SATURDAY A H3 JET IS EXPECTED TO PASS TO OUR SOUTH WITH THE
FAVORABLE LEFT EXIT REGION OVER OUR AREA. THIS WILL HELP TO
INCREASE VERTICAL MOTION FROM 00Z TO 12Z SATURDAY. THE H85 LOW
CENTER IS FORECAST TO MOVE JUST TO OUR SOUTH THROUGH THE PERIOD
WITH THE MAJORITY OF THE CWA IN THE BELOW FREEZING SIDE.
MODEL SOUNDINGS ARE INDICATIVE OF SNOW AS SOON AS EVAPORATIVE
COOLING RAPIDLY COOLS THE LOW LEVELS. ONSET OF PRECIP LOOKS TO BE
RAIN AT FIRST...QUICKLY CHANGING TO RASN AND THEN OVER TO ALL SN
SHORTLY AFTER THIS.
TIMING...HIRES GUIDANCE IS HINTING AT A BAND OF PRECIP ACROSS FAR
NORTHERN ZONES AS EARLY AS 18Z. THIS BAND MAY BE LIGHT AT FIRST
AND MAY TAKE SOME TIME TO COOL/MOISTEN UP THE BL BEFORE PRECIP
STARTS TO FALL. THE REST OF THE AREA WILL SEE THE PRECIP START
FROM WEST TO EAST. THE BEST CHANCE FOR ONSET IN THE WEST WILL BE
BETWEEN 20Z AND 22Z. MULTIPLE HRRR RUNS ARE CONSISTENT IN THIS
TIMING. THE HRRR AND OTHER CAMS SUGGEST A 23Z TO 01Z START TIME
FOR THE AREAS ALONG THE MISSISSIPPI RIVER. AREAS ACROSS IL COULD
SEE PRECIP START AS SOON AS 00Z...BUT LIKELY 01Z TO 02Z.
SNOWFALL TOTALS HAVE NOT CHANGED ALL THE MUCH. WITH THE LATEST
GUIDANCE AND TRENDS FROM DPROG DT...IT APPEARS THAT THE HEAVIEST
SNOW HAS SHIFTED SOUTH SOME 40 MILES. THIS PUTS A ROCKFORD TO
CLINTON TO IOWA CITY LINE AS OUR CURRENT BEST GUESS FOR THE
HEAVIEST SNOW AXIS. TOTALS OF UP TO TEN INCHES OR MORE COULD BE
POSSIBLE ALONG THE AXIS.
SOME CONCERNS ABOUT THE FORECAST ARE THE WARM GROUND TEMPS AND THE
EFFECTS OF EVAPORATIVE COOLING. WHILE THE QPF AND SNOW RATIOS
SUPPORT THIS MUCH SNOW...THERE IS A POSSIBILITY THAT THE WARM
GROUND WILL MELT SNOW AND LEAD TO LESS ACCUMULATION THAN FORECAST.
THIS NEEDS TO BE KEPT IN MIND. REGARDLESS OF THE ACTUAL
TOTALS...IMPACTS FROM THIS STORM WILL LIKELY CAUSE DRIVING ISSUES
AS THE SNOW RATE MAY MAKE IT DIFFICULT TO KEEP ROADS CLEARED
...ESPECIALLY LATER AT NIGHT AND IN THE HEAVIER BANDS. THERE ARE
SOME CONCERNS ABOUT ICE FORMING ON UNTREATED ROADWAYS SO BE SURE
TO DRIVE CAUTIOUSLY IF YOU MUST BE OUT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 328 AM CST FRI NOV 20 2015
INITIAL FOCUS IS ON THE EXITING WINTER STORM SATURDAY MORNING...
WHICH WILL BE FOLLOWED BY BITTER COLD TEMPERATURES THROUGH SUNDAY. A
RETURN TO A MORE ZONAL UPPER LEVEL FLOW NEXT WEEK WILL RESULT IN
TEMPERATURES RECOVERING BACK TO NEAR NORMAL WITH INCREASING RAIN
CHANCES IN THE LATTER HALF OF THE WEEK AS GULF MOISTURE RETURNS.
MODEL CONSENSUS HAS THE SURFACE LOW OVER W CENTRAL IL AT 12Z
DEEPENING AND EJECTING NORTHEAST INTO THE GREAT LAKES WITH THE
PASSAGE OF THE UPPER LEVEL VORT MAX FOLLOWED BY ISENTROPIC DOWNGLIDE
AND BRISK WINDS BEHIND THE SYSTEM. THE TIMING OF THE BACK EDGE OF
THE SYSTEM AND THE PASSING DEFORMATION AXIS NW OF THE SURFACE AND
850 MB LOWS HAS BEEN FAIRLY CONSISTENT OVER THE PAST SEVERAL MODEL
RUNS. THIS SUGGESTS ADDITIONAL 1 TO 2 INCH ACCUMULATIONS WILL BE
POSSIBLE PRIMARILY OVER NW IL...WITH TRACE TO QUARTER INCH AMOUNTS
FURTHER WEST AND SOUTH. HOWEVER...EVEN WITHOUT SIGNIFICANT
SNOW...BRISK N-NW WINDS OF 15 TO 25 MPH...POSSIBLY INTO THE 30 MPH
RANGE...MAY CAUSE SOME DRIFTING SNOW ACROSS THE WEST THROUGH THE
MORNING AND WILL KEEP THE CURRENT 18Z EXPIRATION TIME OF THE
HEADLINES GOING FOR NOW. STRONG COLD AIR ADVECTION AND FRESH
SNOWFALL WILL LEAD TO A WINTER-LIKE DAY WITH TEMPERATURES STEADY TO
FALLING THROUGH THE MID TO UPPER 20S EVEN AS THE DEVELOPING LOW
LEVEL ANTICYCLONIC FLOW LEADS TO BREAKS OF SUNSHINE BY AFTERNOON.
SATURDAY NIGHT AND SUNDAY...LIGHTER SURFACE WINDS WITH THE PASSAGE
OF RIDGE AXIS WILL ALLOW MIN TEMPERATURES TO PLUNGE INTO THE SINGLE
DIGITS OVER THE EXPECTED DEEPER SNOW COVERED CENTRAL AND
NORTH...WITH TEENS MAINLY SOUTH OF THE HIGHWAY 34 CORRIDOR.
TEMPERATURES COULD POTENTIALLY END UP EVEN COLDER...DEPENDING ON THE
AMOUNT OF CLOUD COVER IN THE CYCLONIC NW FLOW ALOFT. LITTLE CHANGE
IN THE SURFACE AIRMASS IS EXPECTED FOR SUNDAY UNDER A NW FLOW ALOFT
WITH HIGHS FROM THE MID 20S NE TO THE MID 30S SW
A GRADUAL WARMUP FOLLOWS FOR MONDAY THROUGH WED AS THE UPPER LEVEL
TROUGH MOVES EAST ALLOWING TO A MORE ZONAL FLOW TO DEVELOP OVER THE
CENTRAL U.S. THIS WILL LEAD TO HIGH TEMPERATURES RECOVERING FROM IN
THE 30S MONDAY...BACK TO NEAR LATE NOVEMBER NORMALS IN THE 40S BY
WED. THE NEXT SYSTEM MOVING INTO THE WEST WILL SEND ANOTHER ROUND OF
GULF MOISTURE NORTHWARD FOR INCREASING RAIN CHANCES WED NIGHT
THROUGH FRIDAY WITH TEMPERATURES LIKELY TRENDING NEAR TO ABOVE
NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1129 AM CST FRI NOV 20 2015
VFR CONDITIONS WILL RAPIDLY DETERIORATE TO MVFR/IFR CONDITIONS BY
00Z/21 WITH SNOW. THERE MAY BE A BRIEF PERIOD OF A RAIN/SNOW MIX
BEFORE IT QUICKLY CHANGES OVER TO ALL SNOW. THE EXCEPTION MAY BE
KBRL WHERE A RAIN/SNOW MIX MAY HOLD ON A BIT LONGER. WIDESPREAD
LIFR CONDITIONS WITH SNOW ARE EXPECTED SHORTLY AFTER 00Z/21.
CONDITIONS WILL BEGIN IMPROVING TO IFR AND EVENTUALLY VFR AFT
12Z/21.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON CST SATURDAY
FOR BENTON-BUCHANAN-CEDAR-CLINTON-DELAWARE-DUBUQUE-IOWA-
JACKSON-JOHNSON-JONES-KEOKUK-LINN-LOUISA-MUSCATINE-SCOTT-
WASHINGTON.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR DES MOINES-HENRY IA-JEFFERSON-LEE-VAN BUREN.
IL...WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON CST SATURDAY
FOR BUREAU-CARROLL-HENRY IL-JO DAVIESS-MERCER-PUTNAM-ROCK
ISLAND-STEPHENSON-WHITESIDE.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR HANCOCK-HENDERSON-MCDONOUGH-WARREN.
MO...WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO NOON CST
SATURDAY FOR CLARK-SCOTLAND.
&&
$$
UPDATE...08
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...SHEETS
AVIATION...08
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1000 AM MST FRI NOV 20 2015
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 203 AM MST FRI NOV 20 2015
LATEST SATELLITE IMAGERY AND RAP H5/H7 ANALYSIS SHOWS SHORTWAVE
TROUGH OVER NORTH CENTRAL WYOMING BEGINNING TO DEEPEN WITH MAIN
MOISTURE AXIS ACROSS NORTHERN NEBRASKA AND SOUTH DAKOTA. AT THE
SURFACE LEE TROUGH IS IN PLACE OVER EASTER COLORADO WITH SOUTHERLY
GRADIENT ACROSS OUR CWA.
TODAY-TONIGHT...SHORTWAVE TROUGH IS ON TRACK TO MOVE THROUGH THE
NORTHERN PLAINS AND DEEPEN WITH A STRONG COLD FRONT DROPPING SOUTH
OVER OUR CWA BY THIS AFTERNOON AND EVENING. MOISTURE PROFILES
CONTINUE TO BE UNIMPRESSIVE...AND THE WINDOW FOR POSITIVE MOISTURE
ADVECTION NARROW. GOOD FORCING AND SPOTTY LIGHT QPF STILL SUPPORT
KEEPING SOME MENTION OF RAIN/SNOW THOUGH CONFIDENCE IS PRETTY LOW WE
WILL SEE MUCH MORE THAN VIRGA OR SPRINKLES/FLURRIES. NAM/ARW/NMM
ACTUALLY SHOW BETTER SIGNAL AFTER 06Z TONIGHT ON BACK SIDE OF UPPER
LOW ASSOCIATED WITH SECONDARY JET STREAK. I KEPT SLIGHT CHANCE POPS
LIMITED TO THE NORTH...TRANSITIONING TO THE WEST DURING THESE
PERIODS WITH SPRINKLES/FLURRIES ELSEWHERE.
WAA ASSOCIATED WITH SOUTHERLY FLOW WILL STILL SUPPORT HIGHS QUICKLY
WARMING AT LEAST IN CLOUD FREE AREAS TO THE 50S BEFORE TEMPERATURES
FALL THIS AFTERNOON BEHIND THE FRONT. LOWS TONIGHT WILL VARY BASED
ON TIMING OF WINDS DECREASING (AND SNOW PACK) AND WITH COLD CANADIAN
AIR MASS IN PLACE LOWS AROUND 10F WILL BE POSSIBLE...AND THE
POTENTIAL FOR SINGLE DIGIT LOW TEMPERATURES EXISTS IN THE WEST.
WHERE WINDS REMAIN HIGHER OVERNIGHT LOWS SHOULD BE CLOSER TO 20F.
AS WAS THE CASE YESTERDAY MODELS SHOW A STRONG PRESSURE GRADIENT
SUPPORTIVE OF AT LEAST NW WINDS GUSTING TO AROUND 40 MPH BASED ON
MIXING HEIGHTS. I STILL CANT RULE OUT SHOWERS MIXING A FEW STRONGER
GUSTS AND IF THIS CORRELATES WITH SNOW COULD REDUCE VISIBILITIES. I
DECIDED NOT TO ADD MENTION OF BLOWING SNOW TO THE GRIDS AND THE
THREAT IS VERY UNCERTAIN/ISOLATED. WILL STILL MAINTAIN MENTION IN
THE HWO.
SATURDAY-SUNDAY NIGHT...ZONAL FLOW AND A DEEP DRY AIR MASS RETURN AND
DRY CONDITIONS WILL PERSIST THROUGH THIS WEEKEND. SHALLOW/COLD AIR
MASS WILL REMAIN IN PLACE THROUGH THE DAY SATURDAY AND HIGHS WILL
GENERALLY BE IN THE 30S (NEAR FREEZING IN PROXIMITY OF SNOW FIELD).
A FEW LOCATIONS IN THE WEST COULD WARM TO AROUND 40 DEPENDING ON
MIXING. WITH INCREASING DOWNSLOPE FLOW/BUILDING LEE TROUGH WAA
INCREASES SUNDAY AND HIGHS IN THE 50S ARE EXPECTED IN AREAS WITHOUT
SNOW PACK. LOWS WILL REFLECT THE GRADUAL WARMING TREND...THOUGH WITH
GOOD RADIATION CONDITIONS/LOWER TD SATURDAY NIGHT WE SHOULD SEE LOWS
IN THE TEENS DESPITE MODERATION ALOFT.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 203 AM MST FRI NOV 20 2015
DRY AND WARM CONDITIONS ARE EXPECTED ON MONDAY AND TUESDAY AS AN
UPPER LEVEL RIDGE FLATTENS OUT ACROSS THE PLAINS AND ZONAL FLOW
DEVELOPS OVER THE REGION. A SHORTWAVE DOES LOOK TO MOVE THROUGH THE
FLOW ON TUESDAY...BUT KEPT THAT PERIOD DRY SINCE LIMITED MOISTURE
SHOULD INHIBIT PRECIP.
QUIET WEATHER PERSISTS FOR THE FORECAST AREA INTO WEDNESDAY AS
RIDGING DEVELOPS AHEAD OF THE NEXT LOW PRESSURE SYSTEM. THIS LOW
TRAVELS FROM THE NORTHWESTERN CONUS TOWARDS THE PLAINS MIDWEEK. A
STRONG COLD FRONT ASSOCIATED WITH THE SYSTEM IS CURRENTLY
ANTICIPATED TO PUSH ACROSS THE HIGH PLAINS WEDNESDAY
NIGHT/THURSDAY...GENERATING RAIN/SNOW CHANCES FOR THE AREA. ONLY
LIGHT ACCUMULATIONS ARE FORECAST AT THIS TIME. LOOKING AHEAD...IT
DOES APPEAR THAT THE REGION WILL SEE BITTER COLD TEMPERATURES JUST
AFTER THE HOLIDAY AS A COLDER AIR MASS PUSHES SOUTH.
TEMPERATURES WILL TREND DOWNWARDS DURING THE EXTENDED PERIOD WITH
HIGHS IN THE 50S ON MONDAY AND TUESDAY COOLING INTO THE UPPER 40S TO
MID 50S FOR WEDNESDAY. THE AREA SHOULD START TO SEE A STEEPER
DECREASE IN TEMPERATURES TOWARDS THE END OF THE WORK WEEK AFTER THE
PASSAGE OF THE COLD FRONT...WITH HIGHS FORECAST IN THE UPPER 30S TO
MID 40S ON THURSDAY. LOWS ARE EXPECTED TO BE IN THE 20S TO LOW 30S
THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1000 AM MST FRI NOV 20 2015
KGLD...VFR CONDITIONS EXPECTED FROM TAF ISSUANCE THROUGH 20Z.
WINDS FROM THE NORTHWEST NEAR 12KTS INITIALLY BUT QUICKEN
INCREASING TO 20KTS GUSTING HIGHER BY 19. AS A COLD FRONT MOVES
THROUGH. FROM 21Z THROUGH 16Z CIGS LOWER TO MVFR RANGE IN POST
FRONTAL MOISTURE. SHOWERS WILL BE AROUND THE TERMINAL INITIALLY AS
RAIN BUT QUICKLY CHANGING TO SNOW LATER THIS AFTERNOON WITH
FLURRIES POSSIBLE EARLY THIS EVENING. WINDS THROUGH 05Z FROM THE
NORTH-NORTHWEST 25G35KTS...FALLING BELOW 12KTS AFTER 06Z. AS THE
SYSTEM EXITS THE AREA AROUND 16Z CIGS QUICKLY IMPROVE TO VFR WITH
WINDS BACKING TO THE WEST JUST UNDER 10KTS.
KMCK...VFR CONDITIONS EXPECTED FROM TAF ISSUANCE THROUGH 19Z WITH
WINDS FROM THE WEST JUST OVER 5KTS. FROM 20Z THROUGH 14Z CIGS
LOWER TO MVFR RANGE. RAIN SHOWERS CHANGING TO SNOW SHOWERS WILL BE
POSSIBLE IN THE 20Z-05Z TIMEFRAME WITH WINDS FROM THE NORTHWEST
GUSTING 25-30KTS. AS THE SYSTEM EXITS THE AREA AROUND 15Z VFR
CONDITIONS RETURN WITH WINDS FROM THE WEST-NORTHWEST 5-10KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...99
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1231 PM EST FRI NOV 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM EST FRI NOV 20 2015
AN UPPER TROUGH OVER ONTARIO IS LEADING TO THE COLDEST AIR THAT WE
HAVE SEEN THIS FALL...WITH 850MB TEMPS -12C AT KINL AT 00Z AND THAT
MATCHES THE RAP ANALYSIS OVER WESTERN LAKE SUPERIOR. A SECONDARY
TROUGH ASSOCIATED WITH THE STRONG LOW OVER HUDSON BAY IS SLOWLY
MOVING EAST ACROSS CENTRAL LAKE SUPERIOR AT THIS TIME AND HAS
SHIFTED WINDS MORE TO THE WEST OVER WESTERN LAKE SUPERIOR. THE COLD
TEMPS HAVE LED TO LAKE EFFECT SNOW IN THE WESTERLY WIND SNOW BELTS.
LOOKING AT WEBCAMS...IT IS TOUGH TO GET A HANDLE ON THE AMOUNT OF
SNOW THAT HAS FALLEN DUE TO THE STRONG WINDS...BUT IT LOOKS TO HAVE
PRODUCED A FEW INCHES IN THE HOUGHTON/CALUMET AREA. THE WINDS HAVE
HELPED CONTRIBUTE TO VISIBILITIES FALLING TO OR BELOW A MILE AT
TIMES AS THEY CONTINUE TO GUST TO 35-40KTS IN THE KEWEENAW.
EXPECT THE LAKE EFFECT TO CONTINUE THROUGH THE SHORT TERM
PERIOD...BUT THE INTENSITY SHOULD BE ON THE DECREASE DUE TO SEVERAL
FACTORS. FIRST...THE DEEP MOISTURE DIMINISHES AS AN UPPER RIDGE
MOVES OVER THE AREA TODAY AHEAD OF A SECONDARY TROUGH MOVING THROUGH
THE NORTHERN ROCKIES. SUBSIDENCE ALOFT WITH THAT RIDGING WILL HELP
LOWER INVERSION HEIGHTS THROUGH THE DAY TOWARDS 7-8KFT (FROM THE
PRESENT 10KFT). SECOND...THE INCREASED CONVERGENCE SEEN ALONG AND
JUST BEHIND THE SURFACE TROUGH WILL DIMINISH THROUGH THE MORNING
HOURS AS THE WINDS BECOME FAIRLY UNIFORM AROUND 270-280 DEGREES.
THERE IS A SECONDARY TROUGH THAT WILL MOVE THROUGH LATE THIS
AFTERNOON AND EARLY THIS EVENING...AND SHIFT WINDS AROUND TO MORE
290-300 DEGREES. THAT WILL BRING MORE LOCATIONS IN THE WESTERN AND
EASTERN U.P. UNDER SOME LAKE EFFECT SNOW (TRADITIONAL NW WIND SNOW
BELTS). ONE OTHER LIMITING FACTOR WILL BE THE CONTINUED INDICATION
BY THE MODELS OF AN INVERTED-V LOOK TO THE LOW LEVELS. THAT BEING
SAID...THE WEAKENING WINDS WILL INCREASE RESIDENCE TIME AND LEAD TO
LESS FRACTURING OF THE FLAKES FOR TONIGHT...SO WOULDN/T BE SURPRISED
TO SEE A FEW LOCATIONS PICKING UP ONE TO LOCALLY TWO INCHES AS MUCH
OF THE CLOUD WILL BE WITHIN THE DGZ. FOR TODAY...EXPECT DAYTIME
ACCUMULATIONS OF 1-2 INCHES OVER THE KEWEENAW AND MAYBE A TOUCH MORE
OVER FAR NORTHEAST LUCE COUNTY WHERE THE LONGER FETCH WILL CREATE
STRONGER BANDS THAT WILL SHIFT SOUTH ALONG THE LUCE COUNTY SHORELINE
IN THE AFTERNOON. AT THIS POINT...THE 15Z END TIME TO THE WINTER WX
ADVISORY LOOKS PRETTY GOOD AS THAT MATCHES UP WELL WITH THE
DIMINISHING TREND IN BOTH THE WINDS AND DEEPER MOISTURE.
WHILE WINDS ARE STILL GUSTING TO 40KTS OVER PORTIONS OF LAKE
SUPERIOR AND THE KEWEENAW PENINSULA AS OF 3AM...THE WEAKENING
PRESSURE GRADIENT THROUGH THE DAY WILL LEAD TO STEADILY DIMINISHING
WINDS THROUGH THE DAY AND EXPECT THEM TO FALL BELOW GALES OVER LAKE
SUPERIOR BY EARLY EVENING. THAT DIMINISHING WILL CONTINUE THROUGH
THE NIGHT AS THEY SHIFT TO THE NORTHWEST. FINALLY...HIGHS TODAY WILL
RANGE FROM THE UPPER 20S OVER THE WEST TO THE LOWER 30S OVER THE
EAST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 525 AM EST FRI NOV 20 2015
AFTER WARM WEATHER SO FAR THIS NOV ACROSS THE UPPER LAKES (AT NWS
MARQUETTE, IT`S BEEN THE WARMEST FIRST 19 DAYS OF NOV ON RECORD)...
SEASONABLY COLD WEATHER WILL BE THE RULE THRU THIS WEEKEND AS A TROF
DOMINATES THE GREAT LAKES REGION. NEXT WEEK...A BUILDING
RIDGE/POSITIVE HEIGHT ANOMALY IN THE GULF OF ALASKA INTO WRN CANADA
WILL FORCE TROFFING INTO THE WRN CONUS...THOUGH THE FLOW WILL BE
SPLIT AND TROF WILL BE POSITIVE TILT. THIS IN TURN WILL FORCE
DOWNSTREAM HEIGHT RISES FROM THE ERN PLAINS TO THE E COAST...
RESULTING IN WARMING FOR THE UPPER LAKES TUE/WED AND PERHAPS THRU
THANKSGIVING DAY. THE BIG UNCERTAINTY THAT MAY IMPACT HOLIDAY TRAVEL
IS HOW QUICKLY THE NRN PORTION OF THE WRN TROF PROGRESSES EASTWARD.
WITH THE SRN STREAM PORTION OF THE TROF STILL HANGING BACK OVER THE
SW STATES/SRN ROCKIES...IT MAY SEND ENERGY NE ALONG THE COLD FRONT
MARKING THE LEADING EDGE OF ARCTIC AIR BEING DRIVEN SE BY THE
POSITIVE HEIGHT ANOMALY IN WRN CANADA...RESULTING IN A BAND OF
WINTRY PCPN SOMEWHERE OVER THE UPPER MISSISSIPPI VALLEY OR WRN GREAT
LAKES LATE WEEK. SEASONABLY COLD WEATHER WILL FOLLOW INTO NEXT
WEEKEND...BUT TONIGHTS 00Z GFS/ECMWF ARE QUICKER PUSHING THE WRN
CANADA POSITIVE HEIGHT ANOMALY EASTWARD...WHICH CUTS OFF THE ARCTIC
AIR BEFORE IT REACHES THE UPPER LAKES. FARTHER OUT...CANADIAN
ENSEMBLES AND THE CFSV2 16 MEMBER ENSEMBLE MEAN FAVOR A RETURN TO
PACIFIC FLOW ACROSS THE NRN CONUS/SRN CANADA. SO...AT THIS
POINT...IT APPEARS AN ABOVE NORMAL TEMP REGIME WILL PROBABALY LOCK
IN AGAIN AFTER THE FIRST FEW DAYS OF DEC. AS FOR PCPN...ONGOING LES
WILL PICK UP SOME SAT AS ENERGY SWINGS SE INTO CNTRL PLAINS THEN NE
INTO THE ERN GREAT LAKES. SYSTEM WILL TRACK FAR ENOUGH S AND SE OF
HERE THAT THE SYNOPTIC SNOW SHIELD SHOULD PASS MOSTLY SE OF THE FCST
AREA. A CLIPPER TYPE SHORTWAVE WILL BRING SOME -SN SUN NIGHT/MON
WITH LAKE ENHANCEMENT OFF LAKE MI POSSIBLE INTO THE FAR ERN FCST
AREA. AFTER A TREND TO DRY WEATHER ON TUE...PCPN WILL RETURN
POSSIBLY AS EARLY AS WED AND CONTINUE INTO FRI.
BEGINNING SAT...SHORTWAVE SWINGING THRU THE PLAINS FRI NIGHT WILL
BEGIN TO SPIN UP A SFC WAVE THAT SHOULD BE IN THE VCNTY OF WRN IL AT
12Z SAT. AS THE SHORTWAVE LIFTS TOWARD THE ERN GREAT LAKES...THE LOW
WILL DEEPEN AND TRACK TO THE VCNTY OF DETROIT BY SAT EVENING. THE
REGIONAL CANADIAN AND NCEP ARW/NMM ARE THE DEEPEST/FARTHEST W
SOLUTIONS AND ARE NEARLY IDENTICAL WITH A TRACK TO NEAR SAGINAW BAY.
THE GFS IS A LITTLE FARTHER SE AND THE NAM/ECMWF ARE
WEAKEST/FARTHEST SE WITH A TRACK TO FAR WRN LAKE ERIE. THE CANADIAN
HAS TRENDED NW/STRONGER SINCE THE 12Z RUN...BUT IT IS WITHIN THE
ENVELOP OF THE LAST 5 SOLUTIONS. THE GFS HAS BEEN VERY CONSISTENT IN
THE LAST 5 RUNS. SINCE THE RELATIVELY WARM WATERS OF THE GREAT LAKES
OFTEN CAN HELP PULL DEVELOPING LOW PRES SYSTEMS TO THE W...
ESPECIALLY EARLY IN THE COLD SEASON...FCST WILL LEAN TOWARD THE
FARTHEST W SOLUTIONS OF THE REGIONAL GEM AND NCEP ARW/NMM. THESE
SOLUTIONS RESULT IN LOW-LEVEL FLOW BACKING MORE AND BECOMING MORE
CYCLONIC ACROSS UPPER MI/LAKE SUPERIOR WITH A PERIOD OF NW TO N FLOW
INCREASING LES COVERAGE OVER NRN UPPER MI. RESULT COULD BE THE
POTENTIAL FOR MDT SNOW ACCUMULATIONS OVER MUCH OF THE NCNTRL AND WRN
FCST AREA. THE NE FRINGE OF THE SYNOPTIC SNOW WOULD ALSO BRUSH THE
SE FCST AREA. WITH FCST SOUNDINGS SHOWING DEEPENING MOISTURE AND
FAIRLY HIGH SNOW TO WATER RATIOS...MAY SEE ADVY TYPE SNOWFALL FOR
THE NW TO N WIND FAVORED SNOWBELTS WITH THE MAIN TIME FRAME FOR THE
HEAVIER SNOW ROUGHLY IN THE 18Z SAT TO 06Z SUN TIME PERIOD. OFFICIAL
FCST WILL SHOW 12HR SNOW AMOUNTS OF 2-4 INCHES WHICH IS JUST UNDER
ADVY THRESHOLD FOR LES/HIGH SNOW TO WATER RATIO SNOW. NRN FRINGE OF
SYNOPTIC SNOW SHOULD ONLY YIELD AN INCH OR LESS ACROSS THE SCNTRL/SE
FCST AREA.
BACKING WINDS/DRYING AIR MASS AS HIGH PRES RIDGE ARRIVES SUN WILL
DIMINISH LINGERING LES. IN FACT...EXPECT ALL LES TO END BY LATE
AFTN AS WINDS BACK.
SUN NIGHT/MON...ATTENTION TURNS TO A CLIPPER TYPE SHORTWAVE THAT
REACHES THE UPPER GREAT LAKES MON MORNING. WAA/ISENTROPIC ASCENT
SHOULD YIELD SOME -SN SPREADING ACROSS THE AREA SUN NIGHT WITH
ACCUMULATIONS PROBABLY UNDER 1 INCH. OF MORE CONCERN IS THE BACKING
WINDS WHICH MAY BACK ENOUGH TO LEAD TO LAKE ENHANCEMENT OFF LAKE
MICHIGAN INTO THE FAR ERN FCST AREA SUN NIGHT. FOR NOW...INCREASED
POPS GENERALLY ALONG E OF KISQ/KERY LINE WITH A COUPLE OF INCHES OF
SNOW POSSIBLE.
SOME LIGHT WNW FLOW LES WILL BE POSSIBLE BEHIND THE SHORTWAVE INTO
MON NIGHT. DRY WEATHER WILL RETURN TUE UNDER WAA/BACKING WINDS.
AS ALLUDED TO ABOVE...THE BIG UNCERTAINTY LATER NEXT WEEK WILL BE
HOW QUICKLY THE NRN PORTION OF THE WRN TROF PROGRESSES EASTWARD.
WITH THE SRN STREAM PORTION OF THE TROF HANGING BACK OVER THE SW
STATES/SRN ROCKIES...THERE WILL BE THE POTENTIAL FOR A DECENT PCPN
EVENT ALONG THE COLD FRONT MOVING INTO THE GREAT LAKES. AT THIS
POINT...RECENT GFS/ECMWF RUNS SUGGEST RAIN DEVELOPING LATE WED INTO
THANKSGIVING DAY WITH A TRANSITION TO SNOW FROM NW TO SE
THANKSGIVING NIGHT/FRI. IT REMAINS TO BE SEEN WHETHER THIS WILL
DEVELOP INTO A SIGNIFICANT PCPN EVENT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1230 PM EST FRI NOV 20 2015
ONGOING BREEZY WEST WINDS WILL CONTINUE TO SLOWLY DIMINISH THROUGH
THE TAF PERIOD. SKIES ARE CLEARING AT IWD...AND A BROKEN LOW-END
MVFR STRATO-CU DECK REMAINS AT KSAW. THIS SHOULD LAST THROUGH THE
AFTERNOON BEFORE SLIGHTLY VEERING WINDS BRING HIGH-END MVFR CIGS TO
BOTH SITES. LAKE EFFECT SNOW SHOWERS SHOULD GRADUALLY MOVE INTO KIWD
OVERNIGHT...AND KSAW LATE SAT MORNING.
AT KCMX...A PAIR OF LES BANDS CONTINUE TO STRADDLE THE AIRPORT.
VEERING WINDS THIS AFTERNOON SHOULD PUSH THE NORTHERN BAND ACROSS
THE SITE...LEADING TO TEMPORARY IFR VIS. FROM THIS EVENING INTO
SAT...SCATTERED LES IS EXPECTED.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 322 AM EST FRI NOV 20 2015
A TROUGH ASSOCIATED WITH A STRONG LOW PRESSURE SYSTEM OVER HUDSON
BAY WILL CROSS LAKE SUPERIOR THIS EVENING. OVER-WATER INSTABILITY
COMBINED WITH A STRONG PRESSURE GRADIENT WILL RESULT IN WSW STORM
FORCE WINDS TO 50 KNOTS FOR MUCH OF THE OPEN WATERS OF WEST AND
CENTRAL LAKE SUPERIOR THIS EVENING. ONCE THE TROUGH COMPLETELY
CROSSES THE LAKE OVERNIGHT...WINDS WILL SHIFT TO THE WEST AND GUST
TO GALES TO 35-40 KTS THROUGH MUCH OF FRIDAY. THESE STRONG WINDS
WILL DIMINISH STEADILY TO UNDER 25 KTS ON FRI NIGHT/SAT WITH THE
APPROACH OF A WEAK HI PRESSURE RIDGE. A STRONGER N TO NW FLOW UP TO
30 KTS IS POSSIBLE ON SAT NIGHT DEPENDING ON THE TRACK OF A LO PRES
MOVING NE THRU SE ONTARIO. THE FLOW WILL THEN SHIFT TO THE SW UP TO
25 KTS BY LATE SUN INTO MON AS A TRAILING HI PRES RIDGE CROSSES THE
UPPER LAKES AND AHEAD OF ANOTHER LO PRES TROUGH APPROACHING FROM THE
NW. FOLLOWING THE TROF PASSAGE...EXPECT W TO NW WINDS UP TO 25 KTS
ON MON INTO TUE...BUT THEN WINDS WILL SHIFT BACK TO THE SW BY
LATER ON TUE AFTER TRAILING HI PRES SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ250-251-264>267.
GALE WARNING UNTIL 1 PM EST /NOON CST/ THIS AFTERNOON FOR LSZ162-
246-247.
GALE WARNING UNTIL 4 PM EST /3 PM CST/ THIS AFTERNOON FOR
LSZ241>245-263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...TK
MARINE...SRF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1107 AM CST FRI NOV 20 2015
.UPDATED FOR 18Z TAF DISCUSSION BELOW...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 416 AM CST FRI NOV 20 2015
WINTER STORM REMAINS ON TRACK TO BRING MODERATE TO HEAVY SNOW ACROSS
NORTHERN IOWA TODAY. THE NORTHERN EDGE OF THIS BAND SHOULD CLIP FAR
SOUTHERN MINNESOTA WITH UP TO 4 INCHES...SO HAVE ISSUED A WINTER
WEATHER ADVISORY BEING THE FIRST SNOWFALL OF THE SEASON. THE SNOW
WILL QUICKLY END TONIGHT...SETTING THE STAGE FOR THE COLDEST NIGHT
OF THE SEASON WITH LOWS IN THE MID TEENS TO LOWER 20S.
THE MODELS HAVE COME INTO BETTER AGREEMENT...AND WITH THE HIRES
SUITE STARTING TO CAPTURE THIS EVENT FEEL FAIRLY CONFIDENT WITH THE
SHORT TERM FORECAST. THE NCAR 10 MEMBER ENSEMBLE DEPICTS THE
UNCERTAINTY BEST...WITH SOME SOLUTIONS SHOWING HARDLY ANY PRECIP
ACROSS SOUTHERN MN...AND OTHERS SHOWING OVER A HALF TO THREE
QUARTERS OF AN INCH. WITH THE ADDITION OF THE HOPWRF AND HRRR FEEL
THAT SOUTHERN MN MAY GET 0.25 TO 0.40 INCHES OF LIQUID...EQUATING TO
2 TO 4 INCHES USING A BLEND OF THE GFS/NAM/AIR FORCE SNOW RATIOS
AT AROUND 10:1 TO 14:1.
A LATENT HEAT VS NON-LATENT HEAT MODEL COMPARISON SHOWS A SOUTHWARD
SHIFT IN THE TRACK FOR THE LATENT HEAT RUN...WHICH RESEMBLES REALITY
MUCH BETTER THAN THE NON-LATENT HEAT RUN...SO THAT IS ANOTHER VOTE
OF CONFIDENCE THAT THE WARNING CRITERIA SNOWFALL WILL STAY TO THE
SOUTH OF THE FORECAST AREA. LOOKING AHEAD...COLD AIR ADVECTION WILL
BRING A REINFORCEMENT OF SEASONABLY COOL AIR ACROSS THE REGION...AND
EXPECT LOW TEMPERATURE NEAR 20 TONIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 416 AM CST FRI NOV 20 2015
THE LONG TERM IS EXPECTED TO BE LARGELY QUIET UNTIL THE LAST HALF
OF NEXT WEEK...RIGHT IN TIME FOR THANKSGIVING AND BLACK FRIDAY. IN
FACT...IT COULD BE QUITE A STORMY END TO THE MONTH.
COLD AND DRY AIR WILL FOLLOW IN THE WAKE OF THE DEPARTING
PLAINS/GREAT LAKES LOW SATURDAY. HIGHS WILL ONLY BE IN THE 20S.
INCREASING CLOUDS ARE EXPECTED LATE SATURDAY AND SATURDAY NIGHT AS
A REINFORCING TROUGH DIGS SOUTHEAST FROM THE CANADIAN ROCKIES.
THIS...IN COMBINATION WITH A BACKING SURFACE FLOW TO THE
SOUTHWEST SHOULD KEEP TEMPERATURES FROM DROPPING INTO THE SINGLE
DIGITS OR LOW TEENS...ASIDE FROM PERHAPS THE SNOWY AREAS ALONG
I-90 IF CLOUDS ARE DELAYED A BIT. DID RAISE LOWS A COUPLE DEGREES
IN MOST LOCATIONS BUT THEY MAY STILL BE TOO COLD.
MEANWHILE...AN UPPER JET STREAK WILL ROUND THE CREST OF THE
WESTERN RIDGE SATURDAY NIGHT. AN ACCOMPANYING LOW PRESSURE SYSTEM
POLEWARD THE JET WILL BEGIN DIVING SOUTHEAST TOWARD THE ARROWHEAD
OF MN SUNDAY EVENING WITH A WARM FRONT EXTENDING TO THE SOUTHEAST
ACROSS WESTERN WI. THERE MAY BE ENOUGH LIFT AND MOISTURE TO BRING
SOME LIGHT SNOW SUNDAY NIGHT NEAR AND EAST OF THE WARM FRONT.
ACCUMULATIONS WOULD BE MINIMAL AND THE REST OF THE CWA WOULD BE
DRY SLOTTED.
AS THAT SYSTEM PUSHES EAST...THE RIDGE WILL BUILD EASTWARD ACROSS
THE PLAINS EARLY NEXT WEEK. MILDER TEMPERATURES WILL RETURN...BUT
NOT TO THE DEGREE SEEN FOR MUCH OF THIS MONTH. MORE IMPORTANTLY...
A TROUGH WILL DIG DOWN THE WEST COAST AND A POTENT CLOSED UPPER
LOW WILL STALL OVER NEVADA AND UTAH FOR THE REST OF THE WEEK.
LATEST GUIDANCE IS IN DECENT AGREEMENT AND SUGGESTS THIS CLOSED
LOW WILL EVENTUALLY PHASE WITH THE POLAR JET ACROSS CANADA AND
RESULT IN A LARGE SCALE POSITIVELY TILTED TROUGH/REX
BLOCK...MAKING IT QUITE DIFFICULT TO FULLY EJECT THE ENERGY FROM
THE SOUTHWEST THROUGH THE END OF THE PERIOD. A LONG FEED FROM THE
TROPICAL PACIFIC WILL SET UP IN THE MID/UPPER LEVELS AND TRANSPORT
QUITE A BIT OF MOISTURE INTO THE PLAINS AND UPPER MIDWEST. STRONG
HIGH PRESSURE /1035-1045MB/ OVER THE NORTHERN ROCKIES WILL AT THE
SAME TIME FEED THE NORTHERN/CENTRAL PLAINS AND UPPER MIDWEST WITH
COLD BOUNDARY LAYER AIR BEHIND THE QUASI-STATIONARY SURFACE
BOUNDARY. THE RESULT COULD BE A PROLONGED WINTRY MESS BEGINNING
WEDNESDAY NIGHT AND CONTINUING THROUGH THE REST OF THE WEEK. KEPT
THE GRIDS A SIMPLE RAIN/SNOW MIX AT THIS RANGE...BUT THERMAL
PROFILES OFF THE GFS AND ECMWF WOULD SUPPORT MORE OF A
SNOW/SLEET/FREEZING RAIN SCENARIO...AND GIVEN THE MOISTURE FEED
AVAILABLE...MAJOR IMPACTS COULD RESULT. STAY TUNED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1115 AM CST FRI NOV 20 2015
VFR CONDITIONS THROUGHOUT. SNOW WILL STAY SOUTH OF THE TAF SITES
TODAY. WINDS WILL BE RELATIVELY LIGHT TODAY...BUT SHOULD INCREASE
LATER TONIGHT WITH GUSTS IN THE MID TEENS POSSIBLE MAINLY OVER THE
EASTERN SITES.
KMSP...
WILL CONTINUE VFR CONDITIONS DURING PERIOD. SOME CHANCE OF MVFR
CIGS MOVING IN AFTER 06Z AS THE UPPER TROUGH SWINGS EAST. APPEARS
KMSP WOULD BE ON THE EDGE OF THE CIGS IF THEY DID OCCUR.
CONFIDENCE IS TOO LOW TO MENTION NOW. WINDS WILL BE RELATIVELY
LIGHT TODAY...BUT SHOULD INCREASE LATER TONIGHT WITH NORTH
NORTHWEST GUSTS IN THE MID TEENS EXPECTED.
/OUTLOOK FOR KMSP/
SAT NITE...VFR. WIND NW AT 5 TO 9KT
SUN...VFR. WIND SW AT 10G20KT.
MON...VFR. WIND WNW AT 10G15KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY UNTIL 3 AM CST SATURDAY FOR MNZ091>093.
&&
$$
SHORT TERM...JRB
LONG TERM...BORGHOFF
AVIATION...DWE
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1117 AM CST FRI NOV 20 2015
.SHORT TERM: (Through Saturday night)
Issued at 346 AM CST Fri Nov 20 2015
The primary forecast issues through Saturday are related to an
approaching low pressure system: extent of snowfall late tonight
and tomorrow morning, non-diurnal temperatures on Saturday,
strong winds on Saturday, and cold temperatures on Saturday
night.
The upper vort max which will become the focus for wx over the
next 36hrs was just entering ID/MT at 10z per water vapor imagery
and the RAP analysis of the 1.5 PVU sfc. The vort max dives
southeastward and induces surface cyclogenesis today/tonight, and
the resulting sfc low is then lifted northeastward through
MO/IL/IN in response to the approaching upper disturbance.
The surface low really needs to be farther south for even the
northern parts of the LSX CWA to see any appreciable snowfall.
Since no such southern shift has been observed, at best perhaps a
few to several tenths of an inch of snow might collect on grassy
areas in the far northern CWA after colder air on the back side
of the system deepens sufficiently to change light rain over to a
light rain/snow mix. The ground is still warm and no accumulation
is expected on roads. The best time period for any snowflakes is
after midnight on Fri night and before noon on Sat. No winter
headlines are anticipated attm.
Strong CAA on the back side of the aforementioned low pressure
system yields a non-diurnal temperature trend on Saturday. For
some locations, the daily high temperature might actually occur at
midnight. Strong northwest winds are also expected during the day
on Saturday across most of the area, although neither the
sustained winds nor the wind gusts look high enough for a wind
advisory attm (wind advisory criteria is sustained 30-39 mph for
1+ hours or gusts of 45-57 mph). Regardless, the combination of
falling temperatures, gusty northwest winds, and lingering rain
(possibly mixed with snowflakes) on Saturday won`t exactly make
for a Chamber of Commerce kind of day.
Winds should decrease quickly by late Saturday afternoon or early
Saturday evening. A surface high will be migrating across the
area on Saturday night, and some recent model runs now place the
ridge axis across the CWA at 12z Sun. This is significant because
the mostly clear skies and nearly calm winds could enhance
radiational cooling overnight in what is already a chilly air
mass. Overnight lows in the upper teens to lower 20s still look on
track.
A secondary vort max is still expected to move across the area on
Saturday night, but no additional precipitation is expected.
Depending on how much moisture is present aloft, however,
increased mid/high cloudiness associated with this feature could
interfere with the radiational cooling described above.
Kanofsky
.LONG TERM: (Sunday through Thursday)
Issued at 346 AM CST Fri Nov 20 2015
A strong vort max is forecast to dive out of Canada towards the
Great Lakes on Sunday night into Monday, but so far it appears
that the effects of this system will remain to the north and east
of the LSX CWA.
The models continue to show large disagreement for early next
week. Unlike 24hrs ago, the models now have a lead shortwave
zipping across the southern half of the country early in the week
before a much larger low pressure system organizes over the
western CONUS. There are also large differences between recent
runs and last night`s 00z runs with respect to the evolution of
the large low pressure system. The extended forecast generally
follows the recommended CR initialization due to low run-to-run
continuity and overall lack of model agreement.
Kanofsky
&&
.AVIATION: (For the 18z TAFs through 18z Saturday Afternoon)
Issued at 1051 AM CST Fri Nov 20 2015
VFR ceilings will gradually lower overnight...but still remain in
the low-end VFR range. Light showers will form after around
02Z...but visibilities will remain in the VFR range. a strong cold
front will push through the region between 10 and 14Z...with winds
becoming northwest and increasing to 15 to 18 knots with gusts to
25 knots. Ceilings will fall into the low-end MVFR range behind
the cold front. As temperatures fall rapidly behind the
front...rain will mix with and change to snow at KUIN...and mix
with light snow before ending at KCOU. Visibilities may fall into
low-end MVFR at KUIN after around 12Z. Ceilings will begin to
clear from west to east around 18Z.
Specifics for KSTL: VFR ceilings and visibilities expected
overnight. Light showers are possible after around 04Z. A strong
cold front will move through at around 14Z...with southeast winds
shifting to northwest and increasing to 18 to 18 knots with gusts
to 25 to 28 knots. As the front passes...ceilings will fall into
the low-end MVFR range. Ceilings should begin to clear by 21Z.
Browning
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
949 AM MST FRI NOV 20 2015
.UPDATE...
THE GOING FORECAST LOOKS ON TRACK. THE SHORTWAVE TROUGH CONTINUES
TO QUICK MOVE INTO SOUTHERN MONTANA. THE HRRR CONTINUES TO SHOW
CONVECTIVE BANDING THROUGH THIS AFTERNOON...WHICH IS LINING UP
WELL WITH CURRENT RADAR. NO CHANGES MADE. REIMER
&&
.SHORT TERM...VALID FOR TDY AND SAT...
THE FIRST SNOWFALL OF THE SEASON FOR THE BILLINGS AREA IS
CURRENTLY UNDERWAY. AN UNSTABLE NORTHWEST FLOW ALOFT WILL CONTINUE
ACROSS THE FORECAST AREA TODAY. A DISTURBANCE ACROSS SOUTHERN
CANADA WILL MOVE SOUTHEAST ACROSS THE CENTRAL AND SOUTHERN
PORTIONS OF THE STATE. IR SATELLITE IS CURRENTLY SHOWING COLDER
CLOUD TOPS UPSTREAM HEADING SOUTHEAST TOWARD OUR FORECAST AREA.
LIGHT SNOW HAS BEEN FALLING THE PAST HOUR HERE IN BILLINGS. RADAR
OVERNIGHT HAS CONTINUED TO SHOW LIGHT SNOW ACROSS OUR WESTERN
COUNTIES BUT THE LATEST OBSERVATION IN LIVINGSTON HAS REPORTED THE
SNOW HAS STOPPED. HOWEVER...THE SNOW SHOULD START AGAIN AS THIS
NEXT DISTURBANCE MOVES ACROSS THE AREA.
MODELS SHOW THE POSSIBILITY OF SNOW BANDING ALONG AND WEST OF A
SHERIDAN- BILLINGS-ROUNDUP LINE. LAPSE RATES ARE STEEP ON THE
ORDER OF 7-8C/KM. CONFIDENCE IS LOW FOR ADVISORY CRITERIA BEING
MET FOR BILLINGS BUT CAN`T RULE OUT AN ISOLATED 2 TO 3 INCH REPORT
ACROSS SOUTHERN YELLOWSTONE COUNTY. HOWEVER..GIVEN A NORTHWEST
SURFACE FLOW...CONFIDENCE IS HIGHER FOR ADVISORY AMOUNTS ACROSS
SOUTHERN BIG HORN COUNTY HAS THE NORTHWEST SURFACE FLOW WILL
PROVIDE FOR AN UPSLOPE COMPONENT. AS A RESULT...I HAVE ADDED
SOUTHERN BIG HORN COUNTY INTO AN ADVISORY FOR THE REMAINDER OF THE
DAY. MODEL GUIDANCE SHOWS SOME GUSTY NORTHWEST WINDS LATER THIS
MORNING FOR THE SHERIDAN AREA AND THIS MAY DOWNSLOPE INTO SHERIDAN
KEEPING SNOW AMOUNTS LIGHTER SO I WILL LEAVE THEM OUT OF THE
ADVISORY FOR NOW. WE WE WILL CONTINUE TO WATCH HOW THE SNOW
EVOLVES FOR YELLOWSTONE AND SHERIDAN COUNTIES FOR ANY POSSIBLE
ADVISORIES LATER THIS MORNING.
A DRY AND MORE STABLE NORTHWEST FLOW ALOFT WILL BE OVER THE
FORECAST ARE TONIGHT THROUGH SATURDAY NIGHT. TEMPERATURES WILL BE
COLD TODAY WITH HIGHS ONLY IN THE UPPER 20S TO LOWER 30S. SOME
CLEARING TONIGHT COMBINED WITH ANY SNOW COVER WILL ALLOW
TEMPERATURES TO FALL WELL INTO THE TEENS AND POSSIBLY SINGLE
DIGITS. HIGHS SATURDAY WILL BE A BIT WARMER BUT WILL WELL BELOW
NORMAL. HOOLEY
.LONG TERM...VALID FOR SUN...MON...TUE...WED...THU...
VERY INTERESTING WX PATTERN NEXT WEEK...WITH WHAT MAY BE OUR FIRST
REAL BLAST OF WINTER BY WEDNESDAY/THURSDAY. ANYONE WITH
THANKSGIVING TRAVEL PLANS WILL NEED TO MONITOR THE FORECAST
CLOSELY.
FOR SUNDAY AND MONDAY...DOWNSLOPE GRADIENTS WILL PREVAIL UNDER
FLAT RIDGING ALOFT. THIS WILL ALLOW FOR BREEZY CONDITIONS AND
GENERALLY WARMER THAN NORMAL TEMPS WITH HIGHS IN THE 40S TO
PUSHING 50F. STRONGEST WINDS WILL OF COURSE BE ALONG OUR WESTERN
FOOTHILLS. DO NOT SEE QUITE ENOUGH GRADIENT OR MID LEVEL FLOW TO
SUPPORT ADVISORY CRITERIA...BUT WILL HAVE TO KEEP AN EYE ON THE
PRE-FRONTAL PERIOD MONDAY-MONDAY NIGHT AS THIS WILL BE THE FAVORED
TIME.
A SHORTWAVE CURRENTLY IN EASTERN SIBERIA WILL MOVE OVER THE GULF
OF AK...DOWN THE CANADIAN WEST COAST...AND CARVE OUT A LOW OVER
THE NW STATES BY TUESDAY. THE COMBINATION OF ASCENT ASSOCIATED
WITH THIS LOW AND A CANADIAN COLD FRONT WILL BRING OUR ENTIRE
REGION A GOOD CHANCE OF ACCUMULATING SNOW TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT. LATEST MODELS HAVE ACTUALLY TRENDED A BIT EAST
WITH THE UPPER LOW AND SUGGEST A MORE FAVORABLE TRACK FOR PCPN IN
OUR AREA...WITH UPSLOPE FLOW THRU MID LEVELS AS A LEE SIDE COLD
AIRMASS DEEPENS. MUST STRESS THE UNCERTAINTY HERE AS A DEVIATION
IN THE TRACK OF THE LOW AND A QUICKER DRYING FROM THE NW WOULD
NEGATIVELY AFFECT OUR PCPN CHANCES...AS THE LOW IS EXPECTED TO
PUSH INTO THE GREAT BASIN OVER TIME. HAVE CAUTIOUSLY RAISED POPS A
NOTCH WITH TUESDAY NIGHT THROUGH WEDNESDAY NIGHT APPEARING TO BE
THE MOST FAVORED PERIODS. MODEL SPREAD INCREASES BY THURSDAY AS WE
SHOULD EVENTUALLY SEE DRYING FROM NW WITH PASSAGE OF NORTHERN
BRANCH SHORTWAVE...IE DECREASING POPS BY THANKSGIVING DAY.
GFS/ECMWF SUGGEST FORMATION OF A REX BLOCK BY THE END OF NEXT
WEEK...WITH STRONG RIDGING OVER THE CANADIAN ROCKIES AS THE UPPER
LOW CUTS OFF SOMEWHERE OVER THE SW CONUS. THIS WOULD KEEP A SFC
RIDGE AND SLOW-TO-EXIT COLD AIR IN OUR CWA INTO NEXT WEEKEND.
SOMETHING TO KEEP AN EYE ON.
AS FOR TEMPERATURES...AFTER THE AFOREMENTIONED MILD DAYS ON
SUNDAY AND MONDAY...WE WILL BEGIN TO TURN COLDER TUESDAY OR
TUESDAY NIGHT WITH PASSAGE OF A STRONG CANADIAN COLD FRONT.
WEDNESDAY AND THURSDAY WILL ALMOST CERTAINLY BE THE COLDEST DAYS
WE HAVE SEEN YET THIS FALL. GFS/ECMWF/CANADIAN SHOW 850MB TEMPS ON
THE ORDER OF -15C BY 144 HRS...AND THIS IS SUPPORTED BY THE GFS
ENSEMBLE MEAN AS WELL...SO THERE IS CONFIDENCE IN LOWERING
FORECAST TEMPS FOR MIDWEEK. HIGHS IN THE TEENS TO LOW 20S AND LOWS
IN THE SINGLE DIGITS ARE A GOOD FIRST GUESS BUT THESE WILL BE TOO
WARM IF THE LATEST MODEL TRENDS VERIFY...ESPECIALLY IF THERE IS A
SIGNIFICANT SNOW COVER.
JKL
&&
.AVIATION...
SNOW SHOWERS WITH PERIODIC REDUCTIONS TO IFR CONDITIONS WILL
PERSIST UNTIL 19Z. IMPROVING CONDITIONS EXPECTED LATE AFTERNOON
WITH VFR OVERNIGHT. BORSUM
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 030 016/037 026/047 027/048 030/043 019/022 009/019
8/S 10/N 00/N 00/U 01/B 55/S 53/S
LVM 028 013/037 026/043 026/045 028/040 018/019 008/019
8/S 10/N 00/N 00/N 13/O 55/S 43/S
HDN 031 010/037 017/047 022/048 024/045 021/025 010/020
8/S 10/B 00/U 00/U 01/B 35/S 43/S
MLS 028 013/036 017/048 022/047 025/042 022/026 011/022
2/S 10/B 00/U 00/B 01/B 34/S 43/S
4BQ 029 009/036 017/050 022/050 024/046 022/029 012/022
4/S 10/B 00/U 00/U 00/B 25/S 43/S
BHK 025 008/034 015/046 022/045 022/042 022/027 011/022
1/E 10/B 00/B 00/B 00/B 24/S 43/S
SHR 028 005/038 015/048 022/050 023/046 021/027 010/021
8/S 10/B 00/U 00/U 00/B 25/S 54/S
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 PM MST THIS EVENING
FOR ZONES 34-38-40-41-56-64>66.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1252 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 1240 PM CST FRI NOV 20 2015
NOON SURFACE TEMPERATURES WERE ALREADY NEARING MAX TEMPERATURES IN
SOME LOCALES. WITH WEAK COLD ADVECTION CONTINUING THIS AFTERNOON
DON`T THINK TEMPERATURES WILL CLIMB MUCH...BUT WITH NEARLY FULL
SUN MANY AREAS AND NO SNOW COVER...DID BUMP UP TEMPS A FEW PLACES.
ALSO LOWERED SKY COVER IN THE SOUTHWEST EARLY THIS AFTERNOON.
UPDATE ISSUED AT 943 AM CST FRI NOV 20 2015
MADE SOME MINOR ADJUSTMENTS TO SKY COVER AND POPS. OTHERWISE NO
SIGNIFICANT UPDATES TO THE GOING FORECAST. LATEST BOWMAN RADAR
INDICATES SOME LIGHT REFLECTIVITIES TRACKING SOUTHEAST ACROSS
BOWMAN/SLOPE COUNTIES...AND A BRIEF SNOW SHOWER INDICATED AT
BAKER MT SO WILL KEEP A MENTION OF SNOW IN THE FAR SOUTHWEST. THIS
WAS TRIMMED BACK EVEN MORE FROM OUR PREVIOUS FORECAST.
UPDATE ISSUED AT 630 AM CST FRI NOV 20 2015
NO CHANGES OF SIGNIFICANCE WERE MADE WITH THIS UPDATE AS WE ONLY
BLENDED CURRENT OBSERVATIONS WITH RECENT SHORT-RANGE MODEL OUTPUT.
WE HAVE RETAINED A LOW-END CHANCE OF LIGHT SNOW IN FAR SOUTHWEST
ND THROUGH EARLY AFTERNOON...BUT NEITHER UPSTREAM OBSERVATIONS IN
MT NOR RECENT HRRR SIMULATIONS ARE SUGGESTIVE OF MUCH POTENTIAL.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CST FRI NOV 20 2015
A WEAK HIGH PRESSURE RIDGE AXIS EXTENDED FROM SOUTHERN
SASKATCHEWAN SOUTHEASTWARD ACROSS NORTHWESTERN NORTH DAKOTA
THROUGH SOUTH CENTRAL NORTH DAKOTA. THIS RIDGE WAS BETWEEN A
STRONG LOW PRESSURE SYSTEM OVER HUDSON BAY AND ANOTHER LOW OVER
WYOMING. AT UPPER LEVELS...A DEEP UPPER LEVEL LOW WAS OVER HUDSON
BAY...WITH A SECONDARY TROUGH OVER THE NORTHERN ROCKIES AND FRONT
RANGE.
MID LEVEL CLOUD COVER ASSOCIATED WITH THE UPPER LEVEL TROUGH
EXTENDED FROM ALBERTA SOUTHEASTWARD TO SOUTH DAKOTA/NEBRASKA. THE
LOW OVER WYOMING AND UPPER LEVEL TROUGH WAS ASSOCIATED WITH LIGHT
SNOW AND LOWER CLOUDS MAINLY SOUTH AND WEST OF NORTH DAKOTA...BUT
ADDED A MENTION OF A SLIGHT CHANCE OF LIGHT SNOW IN THE FAR
SOUTHWEST THIS MORNING. BOWMAN RADAR INDICATING POSSIBLE LIGHT SNOW
REACHING THE GROUND WITH LIGHT RADAR RETURNS IN THE FAR
SOUTHWEST...MAINLY ALONG AND SOUTH OF HIGHWAY 12. OTHERWISE MID LEVEL
CLOUDS WERE OVER PARTS OF WESTERN AND CENTRAL NORTH DAKOTA...AND
WILL LIKELY CONTINUE TO BRING SOME PARTLY CLOUDY SKIES TO
NORTH DAKOTA. ALSO...A COLD FRONT MOVING SOUTHEAST OUT OF
SASKATCHEWAN IS EXPECTED TO ENTER NORTHWESTERN NORTH DAKOTA
BY DAYBREAK...WITH SOME LOWER LEVEL CLOUDS. THUS A PARTLY TO MOSTLY
CLOUDY DAY EXPECTED. ANOTHER COOL DAY WITH HIGHS FROM 20 TO 30.
ANOTHER COOL NIGHT TONIGHT AS WELL WITH PARTLY TO MOSTLY CLOUDY
SKIES. SOME WARM ADVECTION MAY BEGIN IN THE WEST LATE FRIDAY
NIGHT...BUT STILL EXPECT OVERNIGHT LOWS TO RANGE FROM 5 TO 15.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 AM CST FRI NOV 20 2015
HIGHLIGHTS IN THE LONG TERM INCLUDE GUSTY WINDS SUNDAY AND THE
POSSIBILITY OF WINTER WEATHER IMPACTING THANKSGIVING TRAVEL.
A FEW WEAK AND MOISTURE-STARVED IMPULSES EMBEDDED IN NORTHWEST
FLOW ALOFT WILL CROSS THE REGION THIS WEEKEND. THE 00 UTC MODEL
GUIDANCE CALLS FOR 850-MB WINDS OF 45 TO 55 KT DEVELOPING ACROSS
THE AREA SUNDAY INTO SUNDAY EVENING AS A WEAK CLIPPER-TYPE LOW
TRACKS ACROSS CENTRAL CANADA. THE EFFICIENCY OF MOMENTUM TRANSFER
IS IN QUESTION GIVEN A LACK OF ROBUST COLD AIR ADVECTION...SO WE
ARE NOT CONFIDENT IN HEADLINE-WORTHY GUSTS...BUT IT WILL LIKELY BE
A WINDY DAY REGARDLESS. A BRIEF WARM-UP IS STILL EXPECTED SUNDAY
INTO MONDAY WITH FORECAST HIGHS FROM THE MID 30S TO THE MID 40S F.
BY NEXT WEDNESDAY AND THURSDAY...A DEEP 500-MB LOW IS FORECAST TO
DIG INTO THE GREAT BASIN...AND THAT COULD YIELD SNOWFALL OVER THE
REGION. HOWEVER...THE 00 UTC MODEL SUITE GENERALLY TRENDED FURTHER
SOUTH WITH THE PRIMARY DYNAMIC FORCING THAT REACHES THE PLAINS AND
THUS IT SUGGESTED LOWER SNOWFALL TOTALS IN WESTERN AND CENTRAL ND
THAN PREVIOUS MODEL CYCLES. THUS...CONFIDENCE IN POSSIBLE IMPACTS
TO THANKSGIVING TRAVEL IS NOT VERY HIGH. A SEVEN MEMBER...TIME-
LAGGED ENSEMBLE OF DETERMINISTIC GFS RUNS ALSO YIELDED LESS THAN A
30 PERCENT PROBABILITY OF 0.10 INCHES OR MORE OF LIQUID-EQUIVALENT
PRECIPITATION WEDNESDAY THROUGH THANKSGIVING...FURTHER SUGGESTIVE
OF A LACK OF RUN-TO-RUN MODEL CONSENSUS ON DETAILS OF THE PATTERN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1240 PM CST FRI NOV 20 2015
VFR CONDITIONS IN A LIGHT NORTHERLY SURFACE FLOW TODAY AND THIS
EVENING. FLOW BECOMES MORE WESTERLY LATE TONIGHT AND SATURDAY AS A
WARM FRONT APPROACHES FROM THE WEST. THIS WILL ALSO BRING A BAND
OF CLOUDS INTO WESTERN AND CENTRAL NORTH DAKOTA ON SATURDAY.
EXPECT MAINLY LOWER VFR CLOUDS...BUT SCATTERED MVFR CLOUDS CAN NOT
BE RULED OUT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JV
LONG TERM...CJS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1124 AM CST FRI NOV 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CST FRI NOV 20 2015
PRESENT RADAR SHOWING DEVELOPING SNOW BAND FROM SOUTHWESTERN SOUTH
DAKOTA TO NORTH CENTRAL NEBRASKA VERY EARLY THIS MORNING...THOUGH
NOT SEEING ANY SNOW REACHING THE GROUND ON THE EASTERN EXTENT OF THE
BAND WITH DRY LOW LEVEL AIR IN PLACE. THIS AREA OF SNOW LOOKS TO BE
COLLOCATED WELL WITH MODEL 700 MB FRONTOGENESIS FIELDS. STILL LOOKING
AT A DECENT SNOW EVENT ACROSS THE AREA TODAY WITH STRENGTHENING MID
LEVEL FRONTOGENESIS AND UPPER LEVEL LIFT AIDED BY A JET STREAK
SITUATED THROUGH NORTHERN SOUTH DAKOTA INTO MINNESOTA. MODELS IN
FAIRLY DECENT AGREEMENT ON A STRONG FRONTOGENETIC BAND DEVELOPING
INTO SOUTH CENTRAL SOUTH DAKOTA IN THE EARLY MORNING...THEN
SPLITTING TO THE NORTH AND SOUTH BY LATE MORNING...WITH THE SOUTHERN
BAND BECOMING DOMINATE OVER NORTHWESTERN IOWA BY AFTERNOON AS
OPTIMUM 500-300 MB DIV Q SLIDES THROUGH SOUTHERN SOUTH DAKOTA AND
NEBRASKA DURING THAT TIME FRAME. THIS SCENARIO POINTS TO HEAVY SNOW
DEVELOPING SOUTH OF INTERSTATE 90 DURING THE DAY...WITH AMOUNTS
DECREASING RAPIDLY TO THE NORTH WHERE DRIER AIR WILL BE GREATER AND
FORCING IS LESS. WHAT IS SOMEWHAT DISTURBING IS THAT MOST RECENT
MODEL RUNS...INCLUDING THE RAP AND HRRR ARE TRENDING FARTHER TO THE
NORTH WITH THE MORNING PERIOD SNOWFALL IN THE INITIAL FRONTOGENETIC
BAND...PLACING IT RIGHT ALONG THE INTERSTATE 90 CORRIDOR...BEFORE
COLLAPSING IT SOUTHWARD BY AFTERNOON AS EXPLAINED ABOVE. IN
ADDITION...THEY ARE HINTING AT SOME INSTABILITY OF THE FRONT SO
THERE COULD BE A PERIOD OF HEAVIER SNOWFALL IN THIS VICINITY DURING
THE MORNING HOURS. STILL THINKING THE GENERAL HEAVIER SNOW WILL BE
SOUTH OF I90 FOR MOST OF THE DAY...BUT WILL BE SOMETHING TO KEEP AN
EYE ON. WINDS WILL REMAIN ON THE LIGHTER SIDE TODAY...SO BLOWING
SNOW SHOULD NOT BE AN ISSUE. REMAINED BELOW GUIDANCE WITH RESPECT TO
TEMPERATURES...WITH PRECIPITATION AND WET BULBING EFFECTS...SO
LOOKING AT HIGHS JUST EITHER SIDE OF 30 DEGREES. USING SNOW RATIOS
IN THE RANGE OF 11:1 TO 15:1 AND CURRENTLY PROJECTED TOTAL SNOWFALL
AMOUNTS RANGE FROM JUST UNDER AN INCH ALONG THE HIGHWAY 14
CORRIDOR...TO 4 TO 6 INCHES ALONG THE I90 CORRIDOR...TO 6 TO 9
INCHES SOUTH OF THAT AREA...TRENDING HIGHEST TOWARD NORTHWESTERN
IOWA. IN LIGHT OF ALL THE ABOVE REASONING...ISSUED A WINTER WEATHER
ADVISORY ONE STRIP OF COUNTIES FARTHER TO THE NORTH THAN PREVIOUS
FORECAST...ALONG THE I90 CORRIDOR...WITH A WINTER STORM WARNING FOR
AREAS TO THE SOUTH.
BY THIS EVENING THE MIDLEVEL FRONTOGENETIC FORCING SLIDES EASTWARD
INTO NORTH CENTRAL AND NORTHEASTERN IOWA WITH MAXIMUM UPPER LEVEL
DIV Q FOLLOWING SUIT. WITH THAT...WILL SEE SNOW TAPER OFF FROM WEST
TO EAST DURING THE EVENING. MAY GET SOME CLEARING LATER IN THE
NIGHT...AND WENT ON THE LOWER SIDE OF GUIDANCE...ESPECIALLY IN
EXPECTED SNOW COVERED AREAS...WITH OVERNIGHT READINGS IN THE MID
TEENS NORTH TO AROUND 10 SOUTH OF THE I90 CORRIDOR.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 354 AM CST FRI NOV 20 2015
A DRY FIRST HALF OF THE MEDIUM RANGE FORECAST...WITH MORE UNSETTLED
WEATHER TAKING AIM FOR THE THANKSGIVING HOLIDAY. EARLY ON THIS
WEEKEND...BEHIND TODAYS DEPARTING SNOWSTORM...THE MAIN CONCERN WILL
BE WITH TEMPERATURES. THE FIRST COLD DAY OF THE LATE FALL AND EARLY
WINTER SEASON WILL ARRIVE ON SATURDAY. FRESH SNOW COVER...COMBINED
WITH H850 MB TEMPERATURES -10 TO -14C WILL KEEP TEMPERATURES WELL
BELOW NORMAL THIS WEEKEND. SATURDAYS HIGHS MAY STRUGGLE TO BREAK
FREE FROM THE MID 20S. ON SUNDAY...WE WILL HAVE A RETURN OF
SOUTHWESTERLY BOUNDARY LAYER AND LOW LEVEL FLOW...BUT FRESH SNOW
COVER WILL AGAIN HAMPER TEMPERATURES SIGNIFICANTLY.
QUIET WEATHER THROUGH THE FIRST HALF OF NEXT WEEK AS RIDGING SPREADS
ACROSS THE CENTRAL UNITED STATES. WARM SOUTHERLY FLOW SHOULD BUMP
TEMPERATURES BACK INTO THE 40S AND SHOULD MELT SOME OF THE SNOWPACK.
THE CONCERN COULD THEN TURN TO FOG POTENTIAL IN THE MIDWEEK
TIMEFRAME.
WHILE STILL EARLY...WE WILL HAVE TO KEEP AN EYE ON A DEEP UPPER
THROUGH DIGGING INTO THE SOUTHWESTERN US THIS WEEK. THIS SYSTEM
COULD BRING MESSY WEATHER INTO THE MIDDLE OF THE COUNTRY FOR THE
THANKSGIVING HOLIDAY. MODELS SEEM TO AGREE THAT A COLD FRONT WILL
SURGE THROUGH THE REGION LATE WEDNESDAY INTO THURSDAY. CONSIDERABLE
UPPER LIFT MAY SPREAD ACROSS THE REGION WITH THE H850 BOUNDARY
LINGERING OVER THE COLDER SFC AIR. THIS SOLN COULD PRODUCE A MYRIAD
OF WINTRY WEATHER IN THE LOCAL AREA BY THANKSGIVING AND THE DAY
AFTER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1120 AM CST FRI NOV 20 2015
HEAVY SNOW BAND ACROSS THE AREA AFFECTING I-90 AND SOUTH. VFR
CONDITIONS SHOULD PREVAIL ACROSS EASTERN SOUTH DAKOTA NORTH OF
HIGHWAY 34. INTENSE BAND OF SNOWFALL IS EXPECTED TO DECREASE NEAR
SIOUX FALLS...BY 20 Z...AND DIMISH TO FLURRIES WITHIN A FEW HOURS.
FURTHER TO THE SOUTH...SECOND BAND OF FRONTOGENESIS IS EXPECTED TO
DEVELOP AND CREATE GREATLY REDUCED CONDITIONS ALONG THE HIGHWAY 20
CORRIDOR...INCLUDING KSUX. THESE CONDITIONS WILL IMPROVE THROUGH
THE EVENING HOURS TONIGHT. WIDESPREAD VFR CONDITIONS ARE EXPECTED
ON SATURDAY.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR SDZ063>071.
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR SDZ050-
057>061.
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR SDZ062.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ089-
090-098.
IA...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR IAZ001>003-
012-013-020.
WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR IAZ014-021-
022-031-032.
NE...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR NEZ013-014.
&&
$$
SHORT TERM...JM
LONG TERM...DUX
AVIATION...
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
217 PM CST FRI NOV 20 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 217 PM CST FRI NOV 20 2015
HAVE BEEN TRYING TO INTEGRATE CURRENT RADAR AND SURFACE
OBSERVATIONS INTO THE FORECAST TO FINE TUNE STORM. BOTTOM LINE IS
THE ADVISORIES AND WARNINGS LOOK ON TRACK FOR LOCATION. WE DID
UPDATE THE START TIME. HAVE LEFT THE END TIME ON SATURDAY AS THE
NORTHWEST WINDS OF 15 TO 25 MPH WILL CAUSE SOME DRIFTING...
ESPECIALLY ON THE HIGHER TERRAIN OF SWRN WI AND NERN IA.
CURRENT SNOW BAND IS IMPRESSIVE WITH AMOUNTS NEAR 15 INCHES NEAR
SIOUX FALLS SD TODAY AND MESSY ROADS EXTENDING NOW INTO PARTS OF
NERN IA UNDER THE SNOW BAND. GIVEN A MODERATE SNOW
RATE IN THE CENTRAL-EASTERN IA SNOW BAND...ACCUMULATING SNOW AND
SLICK ROADS HAPPEN FAIRLY QUICK AFTER ONSET. THIS BAND IS WELL
REPRESENTED BY 600-700 MB FRONTOGENESIS FORCING PER RAP ANALYSIS.
THE BAND SHOULD CONTINUE TO SHIFT NORTHEAST THROUGH EARLY EVENING. PER
VIGOROUS SHORTWAVE TROUGH IN KS/NEB MOVING AT US...THE
FRONTOGENESIS THEN REINVIGORATES A BIT LATER EVENING ON A NE-SW
ARC OVER THE SOUTHERN FORECAST AREA...WITH THE MAIN HEAVY SNOW
BAND NEAR HIGHWAY 20 TO I-80 WITH STRONGER FRONTOGENSIS INDICATED
IN THE SHORT TERM MODELS.
BIG PICTURE REMAINS THE SAME FOR THIS STORM. WE HAVENT CHANGED
THE TOTAL LIQUID FROM THIS STORM MUCH...BUT DO HAVE SOME CONCERNS
WITH SNOW RATIOS IN THE WARNING...ESPECIALLY CLOSER TO DUBUQUE AND
THE SOUTHERN HALF OF THE FAYETTE-CLAYTON-GRANT COUNTIES. THE
LATEST RAP AND 20.12Z NAM/GFS OUTPUT RUN THROUGH THE DENDRITIC
GROWTH ZONE COBB TECHNIQUE SUGGEST RATIOS COULD BE IN THE 20-24 TO
1 RANGE. WE HAVE INCREASED THOSE RATIOS TO 17 TO 1 ACROSS THE
WARNING WITH A 150-200 MB DENDRITE GROWTH ZONE SUGGESTED. THIS
RAISES TOTALS TOWARD A FOOT. WINDS WILL INCREASE ACROSS THE SOUTH
INTO THE 15 TO 25 MPH RANGE SATURDAY FOR A BIT OF DRIFTING SNOW.
MAIN MESSAGE IS THE SAME...WITH POSSIBLY A BIT MORE IMPACT ACROSS
THE FAR SOUTH /IA HIGHWAY 3/ WITH 10-12 INCHES AND SOME DRIFTING
SNOW. BELIEVE ACCUMULATING SNOW WILL REALLY BE SOUTH OF I-90...AND
THE HAZARDS LOOK LIKE THEY ARE PLACED WELL.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 217 PM CST FRI NOV 20 2015
NORTHWEST FLOW CONTINUES WITH A COLD WEEKEND. CONSENSUS
DETERMINISTIC MODEL RUNS FROM 20.12Z AGREED WELL ON A DYNAMIC
SYSTEM SHIFTING THROUGH NERN WI RAPIDLY SUNDAY NIGHT. THIS LOOKS
LIKE IT COULD SPREAD SOME SNOW ACROSS NORTHCENTRAL WI...LEAVING BY
MONDAY.
THE WEEK THEN BEGINS TO WARM AS ANOTHER LONGWAVE TROUGH DIGS IN
THE WEST. BY MID-WEEK PRECIPITATION WORKS INTO THE AREA ON A
MOIST FLOW. A CLOUDY PERIOD WITH POSSIBLY PRECIPITATION TYPE
ISSUES. AT THIS TIME IT APPEARS MAINLY LIKE A RAIN/SNOW SCENARIO
BUT DEPENDING ON HOW MOISTURE ARRIVES...SOME FREEZING DRIZZLE
COULD BE AROUND. THE MAIN IDEA NOW IS WARMING AND PRECIPITATION BY
MID-WEEK INTO THANKSGIVING. CONFIDENCE MODERATE WITH GOOD
CONSENSUS ON THE BIG PICTURE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1146 AM CST FRI NOV 20 2015
A SNOW BAND HAS SET UP FROM SOUTHEAST SOUTH DAKOTA INTO THE
WATERLOO IA AREA...WITH ALTOSTRATUS SPREADING NORTH INTO THE TAF
SITES NORTH OF THE BAND. THIS SNOW BAND LOOKS TO STAY MOSTLY SOUTH
OF THE TAF SITES THROUGH TONIGHT...BUT ITS NORTHERN EDGE COULD TRY
TO SNEAK IN THIS EVENING...KNOCKING VISIBILITIES DOWN TO MVFR AT
TIMES. ANY ACCUMULATIONS LOOK TO BE LESS THAN 1 INCH. PLAN ON ANY
LIGHT SNOW TO DEPART OVERNIGHT...FOLLOWED BY CLOUDS CLEARING
DURING THE MORNING HOURS.
PLAN ON WINDS TO BECOME NORTHWESTERLY BY THIS EVENING...FOLLOWED
BY AN INCREASE TO 10-15 KT ON SATURDAY AS THE PRESSURE GRADIENT
TIGHTENS OVER THE REGION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR WIZ054-061.
WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON CST SATURDAY
FOR WIZ055.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON CST
SATURDAY FOR WIZ053.
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ094-095.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON CST
SATURDAY FOR MNZ096.
IA...WINTER STORM WARNING UNTIL 6 AM CST SATURDAY FOR IAZ008-018-019.
WINTER STORM WARNING UNTIL 6 AM CST SATURDAY FOR IAZ009.
WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR IAZ010-011-030.
WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR IAZ029.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1146 AM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 1117 AM CST FRI NOV 20 2015
RADAR IMAGERY AS OF 17Z SHOWED A MESOSCALE SNOW BAND FROM NEAR FSD
TO ALO/VTI...GRADUALLY MARCHING NORTHEASTWARD ON ITS EASTERN
FLANK. THIS BAND CORRELATES WELL WITH 700-600MB FRONTOGENESIS
SHOWN IN THE RAP. THE EASTERN SIDE OF THE BAND HAS HAD TO OVERCOME
LOWER LEVEL DRY AIR...BUT ONCE IT DOES...VISIBILITIES QUICKLY
TANK. IN MARSHALLTOWN IA...THE VISIBILITY DROPPED FROM 10 MILES TO
3/4 IN LESS THAN 1 HOUR AS THE BAND MOVED THROUGH. OVER THE
NORTHWEST PART OF IOWA INTO SOUTHEAST SOUTH DAKOTA...WHERE THE
BAND HAS BEEN STAYING PUT THE LONGEST...SNOWFALL AMOUNTS OF 4 TO 6
INCHES HAVE ALREADY OCCURRED.
20.12Z GFS/NAM/REGIONAL CANADIAN AND 20.15Z RAP/BOULDER HRRR ALL
POINT TO THE FRONTOGENESIS BAND LIFTING INTO NORTHEAST IA AND FAR
SOUTHWEST WI OVER THE COURSE OF THE AFTERNOON...ABOUT 3 HOURS
SOONER THAN PREVIOUSLY FORECAST. AS A RESULT...HAVE STARTED THE
WARNING TIMES ABOUT 3 HOURS EARLIER. ADDITIONALLY...IT APPEARS THE
STRONGEST FORCING WITH THE BAND SLOWS UP...ALONG AN AXIS BETWEEN
HIGHWAYS 20 AND 30. THE AFOREMENTIONED MODELS ALL BOOSTED UP QPF
IN THIS REGION AND HAVE MADE A SIMILAR ADJUSTMENT...BUT DID NOT GO
AS HIGH YET WITH LOW LEVEL DRY AIR CONCERNS IN OUR AREA. MODEL
SOUNDINGS WITHIN THIS STRONGEST FORCING DEPICT ANYWHERE FROM
150-200MB OF DENDRITIC GROWTH ZONE WITH VERY STRONG
LIFT...SUPPORTING SNOW TO WATER RATIOS APPROACHING 20 TO 1.
THEREFORE ALSO BOOSTED SNOW TO WATER RATIOS AND SIMILAR TO
QPF...PLAYED A BIT MORE CONSERVATIVE. NET RESULT IS THAT WE ARE
NOW LOOKING AT 8-12 INCHES FROM FLOYD COUNTY INTO GRANT...HIGHEST
THE CLOSER YOU GET TO HIGHWAY 20.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CST FRI NOV 20 2015
FIRST WINTER STORM OF THE YOUNG WINTER SEASON...AND FORECAST FOCUS
IS SQUARELY ON THAT.
UPPER LEVEL TROUGH AXIS SLATED TO SWING ACROSS THE UPPER MISSISSIPPI
RIVER VALLEY SAT...WITH AN EMBEDDED RIPPLE IN THE FLOW LEADING THE
CHARGE INTO THE AREA LATER THIS AFTERNOON/TONIGHT. NORTH-SOUTH
RUNNING X-SECTION SHOWS STRONG/SLOPING FRONTOGENETIC
RESPONSE...STRONGEST ACROSS CENTRAL-NORTHERN IA AND NORTHERN ILL/FAR
SOUTHERN WI. DON/T SEE MUCH -EPV TO ENHANCE BANDING...BUT A 130 KT
UPPER LEVEL JET WILL ENHANCE THE LIFT VIA THE LEFT EXIT REGION.
HEFTY SWATH OF LOW LEVEL THERMODYNAMICS AND QG CONVERGENCE COME WITH
THE SHORTWAVE. NO LACK FOR FORCING FOR SNOW.
SATURATION WILL BE LIMITING FACTOR IN EXTENT OF THE
PCPN...ESPECIALLY ON ITS NORTHERN FRINGES. BOTH THE GFS AND NAM
BRING THE DEEPEST SATURATION JUST SOUTH OF I-90...PER TIME/HEIGHT X-
SECTIONS AND BUFKIT SOUNDINGS. FACTORING IN WHAT WILL LIKELY BE SOME
BANDING IN THE WEST-EAST RUNNING SWATH OF SNOW AND THOSE DRIER LOW
LEVELS...THERE COULD BE A RATHER QUICK FALL OFF IN
ACCUMULATIONS...SNOW RATES...AND EVEN WHERE SNOW FALLS ON THE
NORTHERN EDGE. WILL PAINT QPF/SNOW AMOUNTS AND CHANCES WITH THIS IN
MIND. SOME MESO MODELS SUGGESTING THE NORTHERN PORTION OF THE SNOW
COULD SLIDE SOUTH OF I-90.
AS FOR AMOUNTS...DENDRITIC ZONE GROWTH REGION AROUND 6 KFT AT DBQ AT
THE ONSET OF THE SNOW...DECREASING THROUGH THE NIGHT. MUCH LOWER TO
THE NORTH. SREF DATA SHOWS HUGE SPREADS...OVER 20 INCHES BETWEEN TOP
AND BOTTOM AT LOCATIONS LIKE DBQ. COBB OUTPUT HAS BEEN FAIRLY STEADY
IN THE GFS/NAM DOWN SOUTH THOUGH...SUGGESTING A FOOT FOR DBQ. SPREAD
IN THE SREF PLUMES LOWERS CONFIDENCE A BIT...BUT STEADINESS IN COBB
PROPS IT UP. GOING 5 TO 8 INCHES ACROSS NORTHEAST IA AND SOUTHWEST
WI AT THE MOMENT. SOME LOCALLY HIGHER AMOUNTS ACROSS THE FAR SOUTH
ARE POSSIBLE - ALL DEPENDING ON WHERE THE MORE INTENSE BANDS SET UP.
TO THE NORTH...AMOUNTS ARE MORE PROBLEMATIC. LOCATIONS ALONG I-90
FROM RST-LSE COULD SEE AN INCH OR SO...OR NOTHING. WILL KEEP
OPTIMISTIC WITH SOME ACCUMULATIONS RIGHT NOW...BUT A SHIFT TO LITTLE
OR NO ACCUMS COULD VERY WELL OCCUR. WITH THAT IN MIND...WILL LEAVE
THE I-90 CORRIDOR OUT OF A WINTER WEATHER ADVISORY FOR THIS MOMENT.
LET TRENDS AND NEXT MODEL RUN CONFIRM THE NEED TO MOVE THE ADV
NORTH. WILL INCLUDE A TIER BELOW THAT...AND THEN ALL WARNING FOR
NORTHEAST IA AND SOUTHWEST WI. SOME LOCATIONS THERE WON/T HIT
TRADITIONAL CRITERIA...BUT WITH IT THE FIRST SIGNIFICANT
SNOWFALL...IMPACTS WILL BE HIGH.
.LONG TERM...(SATURDAY THROUGH THANKSGIVING)
ISSUED AT 330 AM CST FRI NOV 20 2015
SHORTWAVE TROUGH LOOKS TO DROP OUT OF CANADA SUNDAY...SPINNING
ACROSS THE UPPER MISSISSIPPI RIVER VALLEY SUNDAY NIGHT-MONDAY.
STRONG QG CONVERGENCE RESPONSE THROUGH THE LEVELS WITH THE
FEATURE...WITH A HEFTY LEADING PUSH OF LOW LEVEL THERMODYNAMICS.
AMPLE LIFT FOR PCPN PRODUCTION. MODELS KEEP MOST OF THE QPF ACROSS
NORTHERN PARTS OF MN/WI...WHERE THE SATURATION IS DEEPEST. ITS LACK
OF RH IS PREVENTING THE MODELS FROM CHURNING OUT MORE QPF...AND IF
THIS PROGGED LACK OF MOISTURE CAN BE OVERCOME...PCPN WOULD GO FROM
CHANCES IN THE NORTH...TO WIDESPREAD LIKELY. ITS A SYSTEM THAT BEARS
WATCHING...AND COULD PACK A BIT MORE OF A PUNCH THEN MODELS ARE
CURRENTLY INDICATING.
MODELS IN GOOD AGREEMENT WITH QUICKLY TRANSITIONING TO BROAD UPPER
LEVEL RIDGING...THEN SOUTHWEST FLOW FOR TUE-THU. TEMPS AT OR ABOVE
THE SEASONABLE NORMALS TUE-THU. WITH THE SOUTHWEST FLOW WILL COME A
SLUG OF GULF MOISTURE. 850 MB TRANSPORT INCREASES DURING THE
PERIOD...STRONGEST ACROSS THE FORECAST AREA THU AFTERNOON/EVENING.
PWS EXCEED 1 INCH IN THE GFS...WITH NAEFS ANOMALIES HOVERING AROUND
+1. A SFC FRONT WILL BE ENCROACHING FROM THE WEST...AHEAD OF SOME
UPPER LEVEL ENERGY SPITTING OUT OF A DESERT SW TROUGH AND A
SHORTWAVE MOVING ALONG THE CANADIAN/US BORDER. DECENT FRONTOGENETIC
RESPONSE AND SOME QG CONVERGENCE WILL HAVE A HAND IN WORKING ON THAT
MOISTURE TO PRODUCE AREAS OF PRECIPITATION...MOSTLY IN THE FORM OF
RAIN. SOME HINTS IN THE GFS/ECMWF THAT SOME SNOW WOULD BECOME LIKELY
ON THE BACKSIDE OF THE SYSTEM...WITH THE EC A BIT MORE BULLISH ON
THE POTENTIAL. CAN/T RULE OUT THE POTENTIAL FOR A WINTRY MIX EITHER.
HARD TO SAY THIS FAR OUT. WILL LET CONSENSUS SOLUTION PAINT THE PCPN
CHANCES AND REFINE DETAILS AS WE GET CLOSER TO THE THANKSGIVING
HOLIDAY. SUFFICE TO SAY...THERE LOOKS TO BE SOME PCPN IMPACTS FOR
THE HOLIDAY...INCLUDING BLACK FRIDAY SHOPPERS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1146 AM CST FRI NOV 20 2015
A SNOW BAND HAS SET UP FROM SOUTHEAST SOUTH DAKOTA INTO THE
WATERLOO IA AREA...WITH ALTOSTRATUS SPREADING NORTH INTO THE TAF
SITES NORTH OF THE BAND. THIS SNOW BAND LOOKS TO STAY MOSTLY SOUTH
OF THE TAF SITES THROUGH TONIGHT...BUT ITS NORTHERN EDGE COULD TRY
TO SNEAK IN THIS EVENING...KNOCKING VISIBILITIES DOWN TO MVFR AT
TIMES. ANY ACCUMULATIONS LOOK TO BE LESS THAN 1 INCH. PLAN ON ANY
LIGHT SNOW TO DEPART OVERNIGHT...FOLLOWED BY CLOUDS CLEARING
DURING THE MORNING HOURS.
PLAN ON WINDS TO BECOME NORTHWESTERLY BY THIS EVENING...FOLLOWED
BY AN INCREASE TO 10-15 KT ON SATURDAY AS THE PRESSURE GRADIENT
TIGHTENS OVER THE REGION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING FROM 3 PM THIS AFTERNOON TO NOON CST
SATURDAY FOR WIZ054-061.
WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON CST SATURDAY
FOR WIZ055.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON CST
SATURDAY FOR WIZ053.
MN...WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 6 AM CST
SATURDAY FOR MNZ094-095.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON CST
SATURDAY FOR MNZ096.
IA...WINTER STORM WARNING UNTIL 6 AM CST SATURDAY FOR IAZ008-018-019.
WINTER STORM WARNING FROM 3 PM THIS AFTERNOON TO 6 AM CST
SATURDAY FOR IAZ009.
WINTER STORM WARNING FROM 3 PM THIS AFTERNOON TO NOON CST
SATURDAY FOR IAZ010-011-030.
WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR IAZ029.
&&
$$
UPDATE...AJ
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
254 PM MST FRI NOV 20 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 253 PM MST FRI NOV 20 2015
THE MAIN SHORTWAVE TROUGH AXIS CONTINUES TO MOVE EASTWARD ACROSS
THE CWA THIS AFTERNOON. SNOW HAS BEEN GRADUALLY DECREASING TO THE
WEST OF THE LARAMIE RANGE IN RESPONSE TO NVA AND INCREASING LARGE
SCALE SUBSIDENCE ON THE BACK SIDE OF THE SYSTEM...SO NOT EXPECTING
MUCH FOR ADDITIONAL ACCUMULATIONS OUT THERE. INFRARED SATELLITE IS
STILL SHOWING SOME COOLING CLOUD TOPS ACROSS EAST CENTRAL WY INTO
THE NORTHERN NE PANHANDLE...MAINLY WITH THE UPSLOPE ALONG THE PINE
RIDGE. THIS SUGGESTS WIDESPREAD SNOW WILL LIKELY CONTINUE THROUGH
AT LEAST EARLY EVENING BEFORE UPPER-LEVEL SUPPORT WEAKENS. EXPECT
TO SEE SOME LINGERING SNOW SHOWERS OVERNIGHT...BUT POPS SHOULD BE
NIL ACROSS THE CWA BY 09Z.
WINTER STORM WARNINGS FOR THE SNOWY/SIERRA MADRE MOUNTAIN RANGES
WILL REMAIN UNCHANGED. SNOWFALL ESTIMATES FROM SEVERAL SNOTEL OBS
INDICATE AROUND 1 TO 2 FEET WITH A FEW ISOLATED TOTALS AROUND 30
INCHES OVER THE LAST 24 HOURS. ANOTHER INCH OR TWO IS POSSIBLE IN
THE NEXT FEW HOURS. DOWNGRADED THE ARLINGTON WARNING TO A WINTER
WEATHER ADVISORY AS CONDITIONS HAVE IMPROVED...BUT LOW VISIBILITY
CONTINUES IN FALLING/BLOWING SNOW. HAZARDOUS WINTER CONDITIONS ARE
STILL ONGOING OVER THE I80 SUMMIT WITH WYDOT CONTINUING TO REPORT
CLOSURES DUE TO ACCIDENTS. A WINTER WEATHER ADVISORY WILL CONTINUE
UNTIL 11 PM. FINALLY...WILL KEEP THE WINTER WEATHER ADVISORY GOING
FOR THE PINE RIDGE AREA THROUGH THE EVENING. CANCELLED CONVERSE CO
AND THE NORTHERN LARAMIE RANGE EARLY AS THE UPPER-LEVEL SUPPORT IS
NOW EXITING TO THE EAST.
VERY COLD TONIGHT FOR MUCH OF THE AREA. LOCATIONS WHICH RECEIVED
MORE THAN A COUPLE INCHES OF SNOW TODAY WILL LIKELY BE COLDER THAN
SURROUNDING AREAS...ESPECIALLY IF CLOUDS/PRECIP CLEAR OUT EARLIER
THAN EXPECTED. OFFICIAL FORECAST LOW TEMPERATURES ARE SEVERAL DEG
BELOW CONSENSUS MOS GUIDANCE. COULD SEE SUB-ZERO READINGS IN THE
HIGH VALLEYS SUCH AS LARAMIE. WIDESPREAD WIND CHILLS BETWEEN -5 F
AND -20 F CAN BE EXPECTED BY SUNRISE SAT. DRY NORTHWEST FLOW ALOFT
AND WARMING THERMAL PROFILES WILL YIELD IMPROVING CONDITIONS AREA
WIDE ON SATURDAY WITH NO CHANCES FOR PRECIP. BREEZY ALONG AND WEST
OF THE LARAMIE RANGE WITH CAG-CPR GRADIENTS AROUND 50 METERS...BUT
ATTM DO NOT EXPECT WIND HIGHLIGHTS FOR THE WIND PRONE AREAS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 253 PM MST FRI NOV 20 2015
...WINTER STORM POSSIBLE FOR THE THANKSGIVING HOLIDAY...
WE WILL BE UNDER NORTHWEST FLOW SUNDAY. RIDGE AXIS OFF TO THE WEST
ALONG THE WEST COAST. FAIRLY WARM AND DRY THROUGH TUESDAY WITH
GRADUALLY WARMING TEMPERATURES EACH DAY. UPPER RIDGE AXIS MOVES
OVER WYOMING MONDAY AFTERNOON WITH 700MB TEMPERATURES MAXING OUT
ABOVE FREEZING.
INCREASING WESTERLY WINDS TUESDAY AS RIDGE AXIS MOVES EAST.
DOWNSLOPING WINDS OFF THE LARAMIE RANGE COULD VERY WELL PUSH HIGHS
INTO THE 60S TUESDAY.
VERY GOOD AGREEMENT BETWEEN THE GFS AND ECMWF ON TIMING...PRECIP
PLACEMENT AND TOTALS ON A PACIFIC STORM SYSTEM MOVING INTO
WYOMING. WE SHOULD BEGIN SEEING PRECIP OUT WEST IN CARBON COUNTY
AS EARLY AS WEDNESDAY MORNING...MORE LIKELY WEDNESDAY EVENING.
ASSOCIATED COLD FRONT MOVES THROUGH SOUTHEAST WYOMING WEDNESDAY
MORNING WITH 700MB TEMPERATURES FALLING TO -12 TO -14C WEDNESDAY
AFTERNOON. THIS WILL BE ALL SNOW WITH THESE VERY COLD 700MB
TEMPERATURES.
IF TRAVELING THROUGH SOUTHEAST WYOMING WEDNESDAY INTO THURSDAY
NEXT WEEK...YOU WILL DEFINITELY WANT TO STAY UP ON THE FORECAST
FOR THIS PART OF THE COUNTRY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1029 AM MST FRI NOV 20 2015
SECOND DISTURBANCE BEGINNING TO MOVE INTO CENTRAL WYOMING LATE
THIS MORNING....MOVING EAST SOUTHEAST. THIS DISTURBANCE WILL BRING
ANOTHER SHOT OF WIDESPREAD LIGHT SNOW AND IFR CONDITIONS TO OUR
AIRPORTS. QUESTION IS...HOW FAR SOUTH WILL THE SNOW/IFR CONDITIONS
GET. FOLLOWED HRRR GUIDANCE THAT KEEPS IFR/LIFR CONDITIONS GOING
FOR MOST OF THE PANHANDLE AND HERE AT KCYS THROUGH THE AFTERNOON.
UPSLOPE WINDS AT KLAR SHOULD CONTINUE TO CREATE IFR CONDITIONS IN
SNOW FOR THERE.
&&
.FIRE WEATHER...
ISSUED AT 253 PM MST FRI NOV 20 2015
MINIMAL FIRE WEATHER CONCERNS FOR MOST AREAS AS RECENT SNOWFALL
AND COLDER TEMPERATURES WILL KEEP FIRE WEATHER CONCERNS AT BAY.
SNOW TO END ACROSS THE AREA BY SATURDAY MORNING WITH A DRY PERIOD
AHEAD THROUGH AT LEAST MID WEEK. NEXT CHANCES FOR SNOW APPEAR TO
BE WEDNESDAY NIGHT INTO THANKSGIVING TIMEFRAME.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 11 PM MST THIS EVENING FOR WYZ110-112-
114.
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR
WYZ101>103-106-116-117.
NE...WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR NEZ002-
095.
&&
$$
SHORT TERM...CLH
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1033 AM MST FRI NOV 20 2015
.SHORT TERM...(TODAY THROUGH SUNDAY AFTERNOON)
ISSUED AT 338 AM MST FRI NOV 20 2015
TODAY...QUITE SURPRISED THAT WINDS HAVE NOT INCREASED AS MUCH AS
EARLIER ANTICIPATED ACROSS THE SOUTHERN LARAMIE RANGE. WATCHING
TRENDS THE PAST FEW HOURS...AND SINCE THE WORK HEIGHT PRODUCT
SHOWS LOWERING HEIGHT DIFFERENCES THE NEXT FEW HOURS...WILL LIKELY
CANCEL THE HIGH WIND WARNING EARLY FOR THE INTERSTATE 80 SUMMIT.
WATCHING SATELLITE AND RADAR TRENDS...A BAND OF LIGHT TO MODERATE
SNOW CONTINUES TO DESCEND SOUTHWARD ACROSS OUR NORTHERN
COUNTIES...AND WITH PROGGED QPF...STILL EXPECTING AT LEAST 1 TO 3
INCHES OF SNOW OVER OUR NORTHERN COUNTIES FROM DOUGLAS TO CHADRON
AND NOT ENOUGH CONFIDENCE TO DROP THE WINTER WEATHER ADVISORY THERE
AS WOULD NOT BE SURPRISED TO SEE A POWDERY SNOWFALL OF AROUND 3
INCHES IN A FEW LOCATIONS THERE.
AS FOR THE WINTER STORM WARNING OVER OUR SNOWY AND SIERRA MADRE
RANGES AND THE NORTHERN SNOWY FOOTHILLS...SNOW HAS BEEN SLOW TO
DEVELOP AND INCREASE IN INTENSITY THERE. HOWEVER...BASED ON THE
MODEL PROGS...STILL BELIEVE THERE WILL BE A PERIOD OF 6 TO 12 HOURS
OF AT LEAST MODERATE SNOW ALONG WITH STRONG GUSTY WINDS PRODUCING
LIMITED VISIBILITIES TO WARRANT CONTINUING THE WINTER STORM WARNING
EVEN THOUGH TOTAL SNOWFALL ACCUMULATIONS WILL LIKELY BE LESS THEN
EARLIER ANTICIPATED.
TONIGHT...CLEARING AND COLD WITH FRESH SNOW COVER AND LIGHT
WINDS...PRODUCING LOW TEMPERATURES IN THE SINGLE DIGITS AND LOWER
TEENS.
SATURDAY...WITH FRESH SNOW COVER AT MOST LOCATIONS AND A COLD
AIRMASS OVERHEAD...TEMPERATURES WILL STRUGGLE TO CLIMB TO ABOVE
FREEZING...THOUGH FORTUNATELY WINDS WILL BE RELATIVELY LIGHT.
SATURDAY NIGHT/SUNDAY...NOT QUITE AS COLD OVERNIGHT AS THE AIRMASS
BEGINS TO MODERATE AND LOW LEVEL MIXING AIDS IN KEEPING IT SLIGHTLY
WARMER. WARMING TREND BEGINS IN EARNEST WITH 700 MB TEMPERATURES
RISING TO NEAR -1 CELSIUS AND WITH DOWNSLOPE WEST WINDS SO
WIDESPREAD 40S EXPECTED EAST OF INTERSTATE 25 WITH ABOVE FREEZING
MAXIMUM TEMPERATURES WEST OF I-25.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 411 AM MST FRI NOV 20 2015
TRANQUIL WEATHER WILL BE IN PLACE FOR MUCH OF THE LONG TERM
FORECAST PERIOD UNDER THE INFLUENCE OF UPPER LEVEL RIDGING.
TEMPERATURES WILL START OFF ON THE CHILLY SIDE SUNDAY MORNING WITH
SINGLE DIGITS AND TEENS ACROSS THE AREA. TEMPERATURES WILL
MODERATE INTO THE 30S AND 40S BY SUNDAY AFTERNOON. WARMER WEATHER
WILL SPREAD INTO THE AREA FOR MONDAY AND TUESDAY AS THE RIDGE AXIS
SHIFTS ACROSS THE ROCKIES. ONE MORE NICE DAY IS POSSIBLE WEDNESDAY
BUT THAT DEPENDS ON HOW FAST THE NEXT UPPER LEVEL TROUGH
PROGRESSES EASTWARD ACROSS THE WESTERN CONUS. WILL CERTAINLY SEE
INCREASING CLOUD COVER BUT THE BEST CHANCES FOR PRECIPITATION MAY
HOLD OFF UNTIL THURSDAY. EXTENDED MODELS DIFFER IN THE DETAILS BUT
GENERALLY SHOW A LARGE CUTOFF LOW OVER IMPACTING THE FORECAST AREA
THROUGH LATE NEXT WEEK AND POTENTIAL INTO NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1029 AM MST FRI NOV 20 2015
SECOND DISTURBANCE BEGINNING TO MOVE INTO CENTRAL WYOMING LATE
THIS MORNING....MOVING EAST SOUTHEAST. THIS DISTURBANCE WILL BRING
ANOTHER SHOT OF WIDESPREAD LIGHT SNOW AND IFR CONDITIONS TO OUR
AIRPORTS. QUESTION IS...HOW FAR SOUTH WILL THE SNOW/IFR CONDITIONS
GET. FOLLOWED HRRR GUIDANCE THAT KEEPS IFR/LIFR CONDITIONS GOING
FOR MOST OF THE PANHANDLE AND HERE AT KCYS THROUGH THE AFTERNOON.
UPSLOPE WINDS AT KLAR SHOULD CONTINUE TO CREATE IFR CONDITIONS IN
SNOW FOR THERE.
&&
.FIRE WEATHER...
ISSUED AT 338 AM MST FRI NOV 20 2015
MINIMAL CONCERNS BASED ON PROJECTED WINDS AND
HUMIDITIES FOR THE NEXT SEVERAL DAYS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 11 PM MST THIS EVENING FOR WYZ110-112-
114.
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR
WYZ101>103.
NE...WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR NEZ002-
095.
&&
$$
SHORT TERM...RE
LONG TERM...SML
AVIATION...GCC
FIRE WEATHER...RUBIN