Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 12/04/15
AREA FORECAST DISCUSSION
NWS ALBANY NY
933 PM EST THU DEC 3 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTHEAST OF NEW BRUNSWICK
OVERNIGHT. HIGH PRESSURE WILL BEGIN BUILDING INTO THE REGION ON
FRIDAY...AND REMAINS ANCHORED OVER THE REGION THROUGH THE WEEKEND.
ASIDE FROM A FEW SNOW SHOWERS ACROSS THE ADIRONDACKS AND SOUTHERN
GREENS THROUGH FRIDAY...IT WILL BE DRY WITH INCREASINGLY MILD
WEATHER THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 933 PM EST...THE CLOSED H500 LOW HAS MOVED OVER NOVA SCOTIA
ACCORDING TO THE LATEST RAP GUIDANCE. THE OCCLUDED SFC LOW
CONTINUES TO MOVE OVER NOVA SCOTIA AND NORTHEAST OF NEW BRUNSWICK.
THE LATEST KENX AND REGIONAL RADAR IMAGERY SHOWS A TRANSITION TO
THIN MULTIBANDS IN THE LOW AND MID LEVEL NW FLOW. THE TREND WILL
BE FOR THE INVERSION TO LOWER ON THE KALY SOUNDING TO LESS THAN 8
KFT AGL...AND THE THIN MULTIBANDS OF ISOLD-SCT SNOW SHOWERS TO
WEAKEN AFTER MIDNIGHT. THE LATEST HRRR HAS ALL THE ISOLD-SCT SNOW
SHOWER ACTIVITY ENDING SHORTLY AFTER 06Z. SOME ISOLD-SCT ACTIVITY
MAY REGENERATE OVER THE WRN DACKS BTWN 09Z-12Z...AS THERE IS SOME
WEAK WARM ADVECTION AHEAD OF THE NEXT WEAK UPPER LEVEL
DISTURBANCE.
THE SKIES WILL BECOME PARTLY CLOUDY FROM THE HUDSON RIVER VALLEY
EASTWARD WELL AFTER MIDNIGHT...AND THE WINDS WILL CONTINUE TO
LIGHTEN WITH THE WEAKENING SFC PRESSURE GRADIENT...TO 5-10 MPH
WITH THE SFC HIGH TRYING TO BUILD IN FROM THE CNTRL MS RIVER
VALLEY AND MIDWEST. LOWS WILL RANGE FROM THE 20S TO L30S ACROSS
THE FCST AREA.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
WE STILL LOOK FOR ONE MORE PIECE OF ENERGY (VIA A SHORT WAVE)
TO WORK JUST NORTH OF OUR REGION FRIDAY. THIS DISTURBANCE WILL
LIKELY SPREAD A FEW CLOUDS ACROSS THE ENTIRE REGION FRIDAY...
BUT ONLY BRING THE CHANCE OF ADDITIONAL SNOW SHOWERS ACROSS MAINLY
THE ADIRONDACKS. THESE SHOULD BE LIGHT AND ADD UP TO AN INCH
OR LESS.
OTHERWISE...WE WILL BE PARTLY SUNNY...BRISK BUT REALLY NOT COLD FOR THE
TIME OF YEAR. LOOK FOR HIGHS IN THE MID TO UPPER 40S IN THE
VALLEY 35-40 HIGHER TERRAIN. A SURFACE TROUGH ASSOCIATED WITH THE
DISTURBANCE WILL INCLUDE A LIGHT SOUTH TO SOUTHWEST WIND 5-10 MPH
IN THE MORNING... VEERING TO WEST BY LATE IN THE DAY 5-15 MPH AS
THE TROUGH MOVES BY.
FRIDAY NIGHT...SPRAWLING HIGH PRESSURE WILL BUILD INTO THE REGION...
NOT ONLY AT THE SURFACE BUT ALOFT.
FRIDAY NIGHT WILL BE PARTLY CLOUDY WITH A LINGERING BREEZE AND PERHAPS
A FEW MORE FLURRIES OVER THE ADIRONDACKS WHERE THE LOWS WILL BE IN MID 20S.
DRY ELSEWHERE WITH LOWS AROUND 30.
LOT OF SUNSHINE LOOKS TO BE IN STORE FOR THE WEEKEND AS HIGH PRESSURE
CONTINUES TO HOLD ITS GROUND OVER THE REGION. HIGH TEMPERATURES
ON SATURDAY WILL RANGE FROM THE UPPER 30S ACROSS THE ADIRONDACKS...
40S MOST OTHER PLACES...LOCALLY UPPER 40S ACROSS THE CAPITAL
REGION AND FURTHER SOUTH.
WITH A CLEAR SKY SATURDAY NIGHT AND LITTLE OR NO WIND...FIFTEEN HOURS
OF DARKNESS WILL INDUCE GOOD RADIATIONAL COOLING. WE WENT ON THE LOW
SIDE OF GUIDANCE THAT NIGHT WITH LOWS FROM AROUND 20 IN THE REMOTE
AREAS...MID TO UPPER 20S LOCALLY IN THE CAPITAL REGION.
ASSUMING FULL SUNSHINE ON SUNDAY AND EVEN WITH LIMITED MIXING...
HIGH TEMPERATURES LOOK TO REACH AROUND 50 OR HIGHER IN THE VALLEYS...
AND WELL INTO THE 40S EVEN ACROSS MOST OF THE HIGHER TERRAIN.
THESE VALUES ARE MORE THAN 10 DEGREES ABOVE NORMAL.
THE WIND BOTH WEEKEND DAYS WILL GENERALLY BE LIGHT AND
VARIABLE AROUND 5 MPH DURING THE DAY...NEAR CALM AT NIGHT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE EXTENDED FORECAST STARTS OUT FAIRLY MILD AND DRY WITH HIGH
PRESSURE NEAR THE EAST COAST. A CUT-OFF OR CLOSED UPPER LEVEL LOW
MAY LIFT FAR ENOUGH NORTH TO NORTHEAST FROM THE MID ATLANTIC REGION
TUE INTO WED ESPECIALLY FROM THE HUDSON RIVER VALLEY SOUTH AND EAST
FOR AN INCREASE IN CLOUDS AND PERHAPS SOME LIGHT RAIN OR VERY LIGHT
SNOW DEPENDING ON THE TIMING AND HOW COLD IT ACTUALLY GETS TUE
NIGHT/WED MORNING.
SUNDAY NIGHT INTO MONDAY...SFC HIGH PRESSURE IS RETREATING OFF THE
EAST COAST. THE MID AND UPPER LEVEL FLOW IS ZONAL OVER SE CANADA
AND THE NORTHEAST...WHILE A CLOSED/CUT-OFF LOW MOVES OVER THE LOWER
MS RIVER VALLEY AND THE SOUTHEAST ACCORDING TO THE GFS...BUT THE
ECMWF IS FURTHER NORTH MOVING IT FROM THE OH VALLEY TO THE MID
ATLANTIC REGION. TEMPS WILL CONTINUE TO RUN ABOVE NORMAL...BUT NOT
AS WARM AS SUNDAY WITH SOME INCREASING CLOUDS AHEAD OF THE UPPER
TROUGH. LOWS WILL RANGE FROM THE 20S TO L30S WITH HIGHS MAINLY IN
THE MID AND U40S IN THE VALLEYS...AND U20S TO L30S OVER THE HIGHER
TERRAIN.
MONDAY NIGHT INTO TUESDAY...THE LATEST ECMWF AND GFS/SEVERAL GEFS
MEMBERS ARE OUT OF PHASE WITH THE PLACEMENT AND MOVEMENT OF THE
CUTOFF. THE ECMWF WOULD HAVE THE CUTOFF SHIFT OFF THE EAST COAST
WITH NO IMPACT ON THE FCST AREA. SEVERAL GEF MEMBERS...THE GEFS
MEAN...AND THE OPERATIONAL GFS ARE SLOWER AND MUCH FARTHER NORTH
WITH THE CUTOFF WITH MORE CLOUDS AND SOME VERY LIGHT RAIN GRAZING
PORTIONS OF THE SE CATSKILLS...MID HUDSON VALLEY...AND NW CT TUE
MORNING INTO THE AFTERNOON. SLIGHT CHC POPS WERE USED FOR LIGHT
RAIN. TO STAY CONSISTENT WITH THE NEIGHBORING WFOS WILL LEAN
TOWARDS THE GFS/GEFS/WPC GUIDANCE. LOWS ONCE AGAIN RANGE FROM THE
M20S OVER THE SRN DACKS TO LOWER 30S OVER THE MID HUDSON VALLEY AND
NW CT. HIGHS TUE WILL BE A TAD COOLER THAN MONDAY WITH M30S TO
AROUND 40F OVER THE HILLS/MTNS...AND 40-45F READINGS IN THE VALLEYS.
TUESDAY NIGHT INTO WEDNESDAY...THE CUTOFF LOW CONTINUES TO LIFT N/NE
AWAY FROM THE FCST AREA WITH ANY VERY LIGHT RAIN/MORNING LIGHT SNOW
ENDING /OVER THE HIGHER TERRAIN/. THE VERTICAL THERMAL PROFILES WILL
DEPEND IF IN ANY VERY LIGHT SNOW OCCURS TUE NIGHT INTO WED. LOWS
TEMPS AND HIGH TEMPS LOOK SIMILAR TO THE PREVIOUS DAY.
WEDNESDAY NIGHT INTO THURSDAY...THE LATEST TRENDS ARE FOR HIGH
PRESSURE TO BUILD IN FROM THE SOUTH WITH FAIR AND DRY WX. ANOTHER
UPPER LEVEL TROUGH WILL BE APPROACHING FROM THE SOUTHEAST AND MID
ATLANTIC REGION LATE IN THE WEEK. THE ECMWF IS QUICKER BRINGING
THIS NEGATIVELY TILTED UPPER TROUGH TOWARDS THE REGION LATE
THU...WHILE THE GFS AND MANY OF ITS ENSEMBLE MEMBERS ARE SLOWER. WE
WILL CONTINUE WITH A DRY FCST FOR NOW. TEMPS WILL STILL BE A LITTLE
ABOVE NORMAL WITH LOWS IN THE U20S TO L30S...AND HIGHS IN THE U30S
TO M40S.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
LOW PRESSURE CONTINUES TO MOVE NORTHEAST OF NEW BRUNSWICK
OVERNIGHT. ANOTHER UPPER LEVEL DISTURBANCE WILL INCREASE CLOUDS
TOMORROW MORNING INTO THE AFTERNOON WITH SOME ISOLATED OR
SCATTERED SNOW OR RAIN SHOWERS NORTH AND WEST OF THE CAPITAL
REGION. HIGH PRESSURE WILL RIDGE IN FROM THE OHIO VALLEY AND THE
UPPER MID ATLANTIC REGION TOMORROW NIGHT INTO SATURDAY.
CONDITIONS ARE EXPECTED TO BE VFR THE NEXT 24 HOURS AT
KGFL/KPSF/KALB/KPOU. THE WINDS WILL GRADUALLY SUBSIDE
OVERNIGHT...AND THE BKN-OVC STRATOCUMULUS IN THE 3.5-6 KFT AGL
RANGE WILL BECOME FEW-SCT ESPECIALLY AFTER 06Z/FRI. THE CLOUDS
WILL INCREASE AGAIN IN THE LATE MORNING INTO THE EARLY AFTERNOON
SCT-BKN035 ESPECIALLY FROM KALB-KPSF NORTHWARD WITH THE UPPER
LEVEL DISTURBANCE. VCSH GROUPS WERE USED FOR KGFL AND KPSF IN THE
AFTERNOON. KPSF WILL HAVE TO BE MONITORED FOR A HIGH MVFR CIG
DURING THE PM. THE CLOUDS SHOULD BEGIN TO DECREASE TOWARD 22Z/FRI.
THE WINDS WILL SUBSIDE FROM THE NW TO W AT 6-12 KTS WITH SOME
GUSTS AROUND 20 KTS AT KPSF...TO 8 KTS OR LESS AFTER MIDNIGHT. THE
WINDS WILL BACK SLIGHTLY TO THE SW/W AT 5-10 KTS TOMORROW AHEAD OF
THE UPPER LEVEL DISTURBANCE...AND THEN SHIFT BACK TO WEST AT
AROUND 6-11 KTS DURING THE AFTERNOON.
OUTLOOK...
FRI NIGHT-TUE: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE EXPECTED THE NEXT 5 DAYS ENDING TUESDAY.
IT LOOKS MAINLY DRY THROUGH THE WEEKEND /OUTSIDE OF SOME SNOW
SHOWER ACTIVITY ACROSS THE HIGHER TERRAIN TONIGHT AND FRIDAY/.
THEREFORE...RIVERS AND STREAMS WILL HOLD STEADY OR SLOWLY RECEDE
SOME OVER THE NEXT SEVERAL DAYS.
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/WASULA
NEAR TERM...WASULA
SHORT TERM...HWJIV
LONG TERM...WASULA
AVIATION...WASULA
HYDROLOGY...IAA/HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
658 PM EST THU DEC 3 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTHEAST OF NEW BRUNSWICK TONIGHT. HIGH
PRESSURE WILL BEGIN BUILDING INTO THE REGION ON FRIDAY...AND
REMAINS ANCHORED OVER THE REGION THROUGH THE WEEKEND. ASIDE FROM A
FEW SNOW SHOWERS ACROSS THE ADIRONDACKS AND SOUTHERN GREENS
THROUGH FRIDAY...IT WILL BE DRY WITH AN INCREASINGLY MILD WEATHER
THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 616 PM EST...THE CLOSED H500 LOW HAS MOVED OVER ERN MAINE
ACCORDING TO THE LATEST RAP GUIDANCE. THE SFC LOW IS MOVING
TOWARDS NEW BRUNSWICK. COLDER AIR CONTINUES TO MOVE ACROSS THE
REGION WITH SOME UPSLOPE SNOW SHOWERS SEEN ON THE KTYX RADAR OVER
THE WRN DACKS...AND ALSO ALONG THE WRN SPINE OF THE SRN GREENS ON
THE KENX/MOSAIC RADAR IMAGERY. WE HAVE INCREASED THE POPS TO HIGH
CHC AND LIKELY VALUES FOR A FEW HOURS FOR LIGHT SNOW ACCUMS OF A
DUSTING TO PERHAPS A HALF AN INCH.
WITH THE LOSS OF THE DAYTIME HEATING AND THE CORE OF THE COLDEST
AIR SHIFTING DOWNSTREAM...THE SNOW SHOWER ACTIVITY SHOULD
DIMINISH OVERNIGHT. THE ONLY EXCEPTION MIGHT BE THE UPSLOPE
TERRAIN OF THE ADIRONDACKS AND SOUTHERN GREENS WHERE RESIDUAL SNOW
SHOWERS MIGHT CONTINUE ON A SCATTERED BASIS...PRODUCING ONLY MINOR
ADDITIONAL ACCUMULATIONS IF ANY AFTER MIDNIGHT.
OTHERWISE...IT WILL BE DRY NIGHT WITH A PARTLY TO MOSTLY
CLOUDY SKY NORTH OF I-90...CLEAR TO PARTLY CLOUDY FURTHER SOUTH.
NW WINDS OF 10-20 MPH...WITH SOME GUSTS TO 30-35 MPH OVER THE
BERKSHIRES/ERN CATSKILLS WILL SLOWLY DIMINISH...TO 10 MPH OR
LESS...AFTER MIDNIGHT.
OVERNIGHT LOW TEMPERATURES WILL SLOWLY FALL TO AROUND 30F IN THE
VALLEYS...DOWN INTO THE 20S OVER THE HIGHER TERRAIN.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
WE STILL LOOK FOR ONE MORE PIECE OF ENERGY (VIA A SHORT WAVE)
TO WORK JUST NORTH OF OUR REGION FRIDAY. THIS DISTURBANCE WILL
LIKELY SPREAD A FEW CLOUDS ACROSS THE ENTIRE REGION FRIDAY...
BUT ONLY BRING THE CHANCE OF ADDITIONAL SNOW SHOWERS ACROSS MAINLY
THE ADIRONDACKS. THESE SHOULD BE LIGHT AND ADD UP TO AN INCH
OR LESS.
OTHERWISE...WE WILL BE PARTLY SUNNY...BRISK BUT REALLY NOT COLD FOR THE
TIME OF YEAR. LOOK FOR HIGHS IN THE MID TO UPPER 40S IN THE
VALLEY 35-40 HIGHER TERRAIN. A SURFACE TROUGH ASSOCIATED WITH THE
DISTURBANCE WILL INCLUDE A LIGHT SOUTH TO SOUTHWEST WIND 5-10 MPH
IN THE MORNING... VEERING TO WEST BY LATE IN THE DAY 5-15 MPH AS
THE TROUGH MOVES BY.
FRIDAY NIGHT...SPRAWLING HIGH PRESSURE WILL BUILD INTO THE REGION...
NOT ONLY AT THE SURFACE BUT ALOFT.
FRIDAY NIGHT WILL BE PARTLY CLOUDY WITH A LINGERING BREEZE AND PERHAPS
A FEW MORE FLURRIES OVER THE ADIRONDACKS WHERE THE LOWS WILL BE IN MID 20S.
DRY ELSEWHERE WITH LOWS AROUND 30.
LOT OF SUNSHINE LOOKS TO BE IN STORE FOR THE WEEKEND AS HIGH PRESSURE
CONTINUES TO HOLD ITS GROUND OVER THE REGION. HIGH TEMPERATURES
ON SATURDAY WILL RANGE FROM THE UPPER 30S ACROSS THE ADIRONDACKS...
40S MOST OTHER PLACES...LOCALLY UPPER 40S ACROSS THE CAPITAL
REGION AND FURTHER SOUTH.
WITH A CLEAR SKY SATURDAY NIGHT AND LITTLE OR NO WIND...FIFTEEN HOURS
OF DARKNESS WILL INDUCE GOOD RADIATIONAL COOLING. WE WENT ON THE LOW
SIDE OF GUIDANCE THAT NIGHT WITH LOWS FROM AROUND 20 IN THE REMOTE
AREAS...MID TO UPPER 20S LOCALLY IN THE CAPITAL REGION.
ASSUMING FULL SUNSHINE ON SUNDAY AND EVEN WITH LIMITED MIXING...
HIGH TEMPERATURES LOOK TO REACH AROUND 50 OR HIGHER IN THE VALLEYS...
AND WELL INTO THE 40S EVEN ACROSS MOST OF THE HIGHER TERRAIN.
THESE VALUES ARE MORE THAN 10 DEGREES ABOVE NORMAL.
THE WIND BOTH WEEKEND DAYS WILL GENERALLY BE LIGHT AND
VARIABLE AROUND 5 MPH DURING THE DAY...NEAR CALM AT NIGHT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE EXTENDED FORECAST STARTS OUT FAIRLY MILD AND DRY WITH HIGH
PRESSURE NEAR THE EAST COAST. A CUT-OFF OR CLOSED UPPER LEVEL LOW
MAY LIFT FAR ENOUGH NORTH TO NORTHEAST FROM THE MID ATLANTIC REGION
TUE INTO WED ESPECIALLY FROM THE HUDSON RIVER VALLEY SOUTH AND EAST
FOR AN INCREASE IN CLOUDS AND PERHAPS SOME LIGHT RAIN OR VERY LIGHT
SNOW DEPENDING ON THE TIMING AND HOW COLD IT ACTUALLY GETS TUE
NIGHT/WED MORNING.
SUNDAY NIGHT INTO MONDAY...SFC HIGH PRESSURE IS RETREATING OFF THE
EAST COAST. THE MID AND UPPER LEVEL FLOW IS ZONAL OVER SE CANADA
AND THE NORTHEAST...WHILE A CLOSED/CUT-OFF LOW MOVES OVER THE LOWER
MS RIVER VALLEY AND THE SOUTHEAST ACCORDING TO THE GFS...BUT THE
ECMWF IS FURTHER NORTH MOVING IT FROM THE OH VALLEY TO THE MID
ATLANTIC REGION. TEMPS WILL CONTINUE TO RUN ABOVE NORMAL...BUT NOT
AS WARM AS SUNDAY WITH SOME INCREASING CLOUDS AHEAD OF THE UPPER
TROUGH. LOWS WILL RANGE FROM THE 20S TO L30S WITH HIGHS MAINLY IN
THE MID AND U40S IN THE VALLEYS...AND U20S TO L30S OVER THE HIGHER
TERRAIN.
MONDAY NIGHT INTO TUESDAY...THE LATEST ECMWF AND GFS/SEVERAL GEFS
MEMBERS ARE OUT OF PHASE WITH THE PLACEMENT AND MOVEMENT OF THE
CUTOFF. THE ECMWF WOULD HAVE THE CUTOFF SHIFT OFF THE EAST COAST
WITH NO IMPACT ON THE FCST AREA. SEVERAL GEF MEMBERS...THE GEFS
MEAN...AND THE OPERATIONAL GFS ARE SLOWER AND MUCH FARTHER NORTH
WITH THE CUTOFF WITH MORE CLOUDS AND SOME VERY LIGHT RAIN GRAZING
PORTIONS OF THE SE CATSKILLS...MID HUDSON VALLEY...AND NW CT TUE
MORNING INTO THE AFTERNOON. SLIGHT CHC POPS WERE USED FOR LIGHT
RAIN. TO STAY CONSISTENT WITH THE NEIGHBORING WFOS WILL LEAN
TOWARDS THE GFS/GEFS/WPC GUIDANCE. LOWS ONCE AGAIN RANGE FROM THE
M20S OVER THE SRN DACKS TO LOWER 30S OVER THE MID HUDSON VALLEY AND
NW CT. HIGHS TUE WILL BE A TAD COOLER THAN MONDAY WITH M30S TO
AROUND 40F OVER THE HILLS/MTNS...AND 40-45F READINGS IN THE VALLEYS.
TUESDAY NIGHT INTO WEDNESDAY...THE CUTOFF LOW CONTINUES TO LIFT N/NE
AWAY FROM THE FCST AREA WITH ANY VERY LIGHT RAIN/MORNING LIGHT SNOW
ENDING /OVER THE HIGHER TERRAIN/. THE VERTICAL THERMAL PROFILES WILL
DEPEND IF IN ANY VERY LIGHT SNOW OCCURS TUE NIGHT INTO WED. LOWS
TEMPS AND HIGH TEMPS LOOK SIMILAR TO THE PREVIOUS DAY.
WEDNESDAY NIGHT INTO THURSDAY...THE LATEST TRENDS ARE FOR HIGH
PRESSURE TO BUILD IN FROM THE SOUTH WITH FAIR AND DRY WX. ANOTHER
UPPER LEVEL TROUGH WILL BE APPROACHING FROM THE SOUTHEAST AND MID
ATLANTIC REGION LATE IN THE WEEK. THE ECMWF IS QUICKER BRINGING
THIS NEGATIVELY TILTED UPPER TROUGH TOWARDS THE REGION LATE
THU...WHILE THE GFS AND MANY OF ITS ENSEMBLE MEMBERS ARE SLOWER. WE
WILL CONTINUE WITH A DRY FCST FOR NOW. TEMPS WILL STILL BE A LITTLE
ABOVE NORMAL WITH LOWS IN THE U20S TO L30S...AND HIGHS IN THE U30S
TO M40S.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
LOW PRESSURE CONTINUES TO MOVE NORTHEAST OF NEW BRUNSWICK
OVERNIGHT. ANOTHER UPPER LEVEL DISTURBANCE WILL INCREASE CLOUDS
TOMORROW MORNING INTO THE AFTERNOON WITH SOME ISOLATED OR
SCATTERED SNOW OR RAIN SHOWERS NORTH AND WEST OF THE CAPITAL
REGION. HIGH PRESSURE WILL RIDGE IN FROM THE OHIO VALLEY AND THE
UPPER MID ATLANTIC REGION TOMORROW NIGHT INTO SATURDAY.
CONDITIONS ARE EXPECTED TO BE VFR THE NEXT 24 HOURS AT
KGFL/KPSF/KALB/KPOU. THE WINDS WILL GRADUALLY SUBSIDE
OVERNIGHT...AND THE BKN-OVC STRATOCUMULUS IN THE 3.5-6 KFT AGL
RANGE WILL BECOME FEW-SCT ESPECIALLY AFTER 06Z/FRI. THE CLOUDS
WILL INCREASE AGAIN IN THE LATE MORNING INTO THE EARLY AFTERNOON
SCT-BKN035 ESPECIALLY FROM KALB-KPSF NORTHWARD WITH THE UPPER
LEVEL DISTURBANCE. VCSH GROUPS WERE USED FOR KGFL AND KPSF IN THE
AFTERNOON. KPSF WILL HAVE TO BE MONITORED FOR A HIGH MVFR CIG
DURING THE PM. THE CLOUDS SHOULD BEGIN TO DECREASE TOWARD 22Z/FRI.
THE WINDS WILL SUBSIDE FROM THE NW TO W AT 6-12 KTS WITH SOME
GUSTS AROUND 20 KTS AT KPSF...TO 8 KTS OR LESS AFTER MIDNIGHT. THE
WINDS WILL BACK SLIGHTLY TO THE SW/W AT 5-10 KTS TOMORROW AHEAD OF
THE UPPER LEVEL DISTURBANCE...AND THEN SHIFT BACK TO WEST AT
AROUND 6-11 KTS DURING THE AFTERNOON.
OUTLOOK...
FRI NIGHT-TUE: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE EXPECTED THE NEXT 5 DAYS ENDING TUESDAY.
IT LOOKS MAINLY DRY THROUGH THE WEEKEND /OUTSIDE OF SOME SNOW
SHOWER ACTIVITY ACROSS THE HIGHER TERRAIN TONIGHT AND FRIDAY/.
THEREFORE...RIVERS AND STREAMS WILL HOLD STEADY OR SLOWLY RECEDE
SOME OVER THE NEXT SEVERAL DAYS.
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/WASULA
NEAR TERM...HWJIV/WASULA
SHORT TERM...HWJIV
LONG TERM...WASULA
AVIATION...WASULA
HYDROLOGY...IAA/HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
616 PM EST THU DEC 3 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTHEAST OF NEW BRUNSWICK TONIGHT. HIGH
PRESSURE WILL BEGIN BUILDING INTO THE REGION ON FRIDAY...AND
REMAINS ANCHORED OVER THE REGION THROUGH THE WEEKEND. ASIDE FROM A
FEW SNOW SHOWERS ACROSS THE ADIRONDACKS AND SOUTHERN GREENS
THROUGH FRIDAY...IT WILL BE DRY WITH AN INCREASINGLY MILD WEATHER
THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 616 PM EST...THE CLOSED H500 LOW HAS MOVED OVER ERN MAINE
ACCORDING TO THE LATEST RAP GUIDANCE. THE SFC LOW IS MOVING
TOWARDS NEW BRUNSWICK. COLDER AIR CONTINUES TO MOVE ACROSS THE
REGION WITH SOME UPSLOPE SNOW SHOWERS SEEN ON THE KTYX RADAR OVER
THE WRN DACKS...AND ALSO ALONG THE WRN SPINE OF THE SRN GREENS ON
THE KENX/MOSAIC RADAR IMAGERY. WE HAVE INCREASED THE POPS TO HIGH
CHC AND LIKELY VALUES FOR A FEW HOURS FOR LIGHT SNOW ACCUMS OF A
DUSTING TO PERHAPS A HALF AN INCH.
WITH THE LOSS OF THE DAYTIME HEATING AND THE CORE OF THE COLDEST
AIR SHIFTING DOWNSTREAM...THE SNOW SHOWER ACTIVITY SHOULD
DIMINISH OVERNIGHT. THE ONLY EXCEPTION MIGHT BE THE UPSLOPE
TERRAIN OF THE ADIRONDACKS AND SOUTHERN GREENS WHERE RESIDUAL SNOW
SHOWERS MIGHT CONTINUE ON A SCATTERED BASIS...PRODUCING ONLY MINOR
ADDITIONAL ACCUMULATIONS IF ANY AFTER MIDNIGHT.
OTHERWISE...IT WILL BE DRY NIGHT WITH A PARTLY TO MOSTLY
CLOUDY SKY NORTH OF I-90...CLEAR TO PARTLY CLOUDY FURTHER SOUTH.
NW WINDS OF 10-20 MPH...WITH SOME GUSTS TO 30-35 MPH OVER THE
BERKSHIRES/ERN CATSKILLS WILL SLOWLY DIMINISH...TO 10 MPH OR
LESS...AFTER MIDNIGHT.
OVERNIGHT LOW TEMPERATURES WILL SLOWLY FALL TO AROUND 30F IN THE
VALLEYS...DOWN INTO THE 20S OVER THE HIGHER TERRAIN.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
WE STILL LOOK FOR ONE MORE PIECE OF ENERGY (VIA A SHORT WAVE)
TO WORK JUST NORTH OF OUR REGION FRIDAY. THIS DISTURBANCE WILL
LIKELY SPREAD A FEW CLOUDS ACROSS THE ENTIRE REGION FRIDAY...
BUT ONLY BRING THE CHANCE OF ADDITIONAL SNOW SHOWERS ACROSS MAINLY
THE ADIRONDACKS. THESE SHOULD BE LIGHT AND ADD UP TO AN INCH
OR LESS.
OTHERWISE...WE WILL BE PARTLY SUNNY...BRISK BUT REALLY NOT COLD FOR THE
TIME OF YEAR. LOOK FOR HIGHS IN THE MID TO UPPER 40S IN THE
VALLEY 35-40 HIGHER TERRAIN. A SURFACE TROUGH ASSOCIATED WITH THE
DISTURBANCE WILL INCLUDE A LIGHT SOUTH TO SOUTHWEST WIND 5-10 MPH
IN THE MORNING... VEERING TO WEST BY LATE IN THE DAY 5-15 MPH AS
THE TROUGH MOVES BY.
FRIDAY NIGHT...SPRAWLING HIGH PRESSURE WILL BUILD INTO THE REGION...
NOT ONLY AT THE SURFACE BUT ALOFT.
FRIDAY NIGHT WILL BE PARTLY CLOUDY WITH A LINGERING BREEZE AND PERHAPS
A FEW MORE FLURRIES OVER THE ADIRONDACKS WHERE THE LOWS WILL BE IN MID 20S.
DRY ELSEWHERE WITH LOWS AROUND 30.
LOT OF SUNSHINE LOOKS TO BE IN STORE FOR THE WEEKEND AS HIGH PRESSURE
CONTINUES TO HOLD ITS GROUND OVER THE REGION. HIGH TEMPERATURES
ON SATURDAY WILL RANGE FROM THE UPPER 30S ACROSS THE ADIRONDACKS...
40S MOST OTHER PLACES...LOCALLY UPPER 40S ACROSS THE CAPITAL
REGION AND FURTHER SOUTH.
WITH A CLEAR SKY SATURDAY NIGHT AND LITTLE OR NO WIND...FIFTEEN HOURS
OF DARKNESS WILL INDUCE GOOD RADIATIONAL COOLING. WE WENT ON THE LOW
SIDE OF GUIDANCE THAT NIGHT WITH LOWS FROM AROUND 20 IN THE REMOTE
AREAS...MID TO UPPER 20S LOCALLY IN THE CAPITAL REGION.
ASSUMING FULL SUNSHINE ON SUNDAY AND EVEN WITH LIMITED MIXING...
HIGH TEMPERATURES LOOK TO REACH AROUND 50 OR HIGHER IN THE VALLEYS...
AND WELL INTO THE 40S EVEN ACROSS MOST OF THE HIGHER TERRAIN.
THESE VALUES ARE MORE THAN 10 DEGREES ABOVE NORMAL.
THE WIND BOTH WEEKEND DAYS WILL GENERALLY BE LIGHT AND
VARIABLE AROUND 5 MPH DURING THE DAY...NEAR CALM AT NIGHT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE EXTENDED FORECAST STARTS OUT FAIRLY MILD AND DRY WITH HIGH
PRESSURE NEAR THE EAST COAST. A CUT-OFF OR CLOSED UPPER LEVEL LOW
MAY LIFT FAR ENOUGH NORTH TO NORTHEAST FROM THE MID ATLANTIC REGION
TUE INTO WED ESPECIALLY FROM THE HUDSON RIVER VALLEY SOUTH AND EAST
FOR AN INCREASE IN CLOUDS AND PERHAPS SOME LIGHT RAIN OR VERY LIGHT
SNOW DEPENDING ON THE TIMING AND HOW COLD IT ACTUALLY GETS TUE
NIGHT/WED MORNING.
SUNDAY NIGHT INTO MONDAY...SFC HIGH PRESSURE IS RETREATING OFF THE
EAST COAST. THE MID AND UPPER LEVEL FLOW IS ZONAL OVER SE CANADA
AND THE NORTHEAST...WHILE A CLOSED/CUT-OFF LOW MOVES OVER THE LOWER
MS RIVER VALLEY AND THE SOUTHEAST ACCORDING TO THE GFS...BUT THE
ECMWF IS FURTHER NORTH MOVING IT FROM THE OH VALLEY TO THE MID
ATLANTIC REGION. TEMPS WILL CONTINUE TO RUN ABOVE NORMAL...BUT NOT
AS WARM AS SUNDAY WITH SOME INCREASING CLOUDS AHEAD OF THE UPPER
TROUGH. LOWS WILL RANGE FROM THE 20S TO L30S WITH HIGHS MAINLY IN
THE MID AND U40S IN THE VALLEYS...AND U20S TO L30S OVER THE HIGHER
TERRAIN.
MONDAY NIGHT INTO TUESDAY...THE LATEST ECMWF AND GFS/SEVERAL GEFS
MEMBERS ARE OUT OF PHASE WITH THE PLACEMENT AND MOVEMENT OF THE
CUTOFF. THE ECMWF WOULD HAVE THE CUTOFF SHIFT OFF THE EAST COAST
WITH NO IMPACT ON THE FCST AREA. SEVERAL GEF MEMBERS...THE GEFS
MEAN...AND THE OPERATIONAL GFS ARE SLOWER AND MUCH FARTHER NORTH
WITH THE CUTOFF WITH MORE CLOUDS AND SOME VERY LIGHT RAIN GRAZING
PORTIONS OF THE SE CATSKILLS...MID HUDSON VALLEY...AND NW CT TUE
MORNING INTO THE AFTERNOON. SLIGHT CHC POPS WERE USED FOR LIGHT
RAIN. TO STAY CONSISTENT WITH THE NEIGHBORING WFOS WILL LEAN
TOWARDS THE GFS/GEFS/WPC GUIDANCE. LOWS ONCE AGAIN RANGE FROM THE
M20S OVER THE SRN DACKS TO LOWER 30S OVER THE MID HUDSON VALLEY AND
NW CT. HIGHS TUE WILL BE A TAD COOLER THAN MONDAY WITH M30S TO
AROUND 40F OVER THE HILLS/MTNS...AND 40-45F READINGS IN THE VALLEYS.
TUESDAY NIGHT INTO WEDNESDAY...THE CUTOFF LOW CONTINUES TO LIFT N/NE
AWAY FROM THE FCST AREA WITH ANY VERY LIGHT RAIN/MORNING LIGHT SNOW
ENDING /OVER THE HIGHER TERRAIN/. THE VERTICAL THERMAL PROFILES WILL
DEPEND IF IN ANY VERY LIGHT SNOW OCCURS TUE NIGHT INTO WED. LOWS
TEMPS AND HIGH TEMPS LOOK SIMILAR TO THE PREVIOUS DAY.
WEDNESDAY NIGHT INTO THURSDAY...THE LATEST TRENDS ARE FOR HIGH
PRESSURE TO BUILD IN FROM THE SOUTH WITH FAIR AND DRY WX. ANOTHER
UPPER LEVEL TROUGH WILL BE APPROACHING FROM THE SOUTHEAST AND MID
ATLANTIC REGION LATE IN THE WEEK. THE ECMWF IS QUICKER BRINGING
THIS NEGATIVELY TILTED UPPER TROUGH TOWARDS THE REGION LATE
THU...WHILE THE GFS AND MANY OF ITS ENSEMBLE MEMBERS ARE SLOWER. WE
WILL CONTINUE WITH A DRY FCST FOR NOW. TEMPS WILL STILL BE A LITTLE
ABOVE NORMAL WITH LOWS IN THE U20S TO L30S...AND HIGHS IN THE U30S
TO M40S.
&&
.AVIATION /23Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS BUT RATHER WINDY CONDITIONS EXPECTED
THROUGH THE EVENING PEAK. SNOW SHOWERS HAVE DIMINISHED A
LITTLE IN COVERAGE AND INTENSITY...SO WE REMOVED THE
TEMPO GROUP DROPPING CONDITIONS TO MVFR AT KPSF.
THE NORTHWEST WIND 10-15 KTS...GUSTING UP TO 30KTS AT KALB
AND KPSF THROUGH ABOUT 00Z...BEFORE SLOWLY DIMINISHING TO
AROUND 5KTS WELL OVERNIGHT.
IT WILL BE PARTLY CLOUDY NIGHT WITH CIGS AT OR ABOVE
3000 FEET...WHICH COULD BRIEFLY FORM CIGS AND MVFR
BUT ENOUGH CONFIDENCE AND INTERVAL TO PLACE ANY MVFR
IN THE TAFS.
FRIDAY LOOKS LIKE A VFR DAY WITH SCT-BKN CLOUDS ABOVE
3000 FEET. A LIGHT OR SOUTH WIND AROUND 5KTS WILL
VEER TO THE NORTHWEST AROUND 10KTS LATER IN THE DAY.
OUTLOOK...
SAT-TUE: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
IT LOOKS MAINLY DRY THROUGH THE WEEKEND (OUTSIDE OF SOME SNOW
SHOWER ACTIVITY ACROSS THE HIGHER TERRAIN TONIGHT AND FRIDAY).
THEREFORE...RIVERS AND STREAMS WILL HOLD STEADY OR DROP
A LITTLE DURING THE
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/WASULA
NEAR TERM...HWJIV/WASULA
SHORT TERM...HWJIV
LONG TERM...WASULA
AVIATION...FRUGIS/HWJIV
HYDROLOGY...IAA/HWJIV
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
830 PM EST THU DEC 3 2015
.DISCUSSION...
...HIGH RAIN CHANCES OVERNIGHT MAINLY SOUTH/EAST OF ORLANDO...
...HAZARDOUS BOATING CONDITIONS FRI-SUN WITH MORE BEACH EROSION
LIKELY...
CURRENT...MID LEVEL TROUGHING COVERS THE U.S. FROM TEXAS TO THE EAST
COAST WITH THE BASE OF THE TROUGH AND TROUGH AXIS OVER LOUISIANA AND
MISSISSIPPI. JET STREAM AXIS AND MAX SPEED CORE WELL NORTH OF FLORIDA
AND OVER VIRGINIA/NORTH AND SOUTH CAROLINA. THE RIGHT REAR QUADRANT WAS
LYING OVER THE SOUTHEAST U.S. FLORIDA AND THE NORTHEAST GULF. THE
LATEST SATELLITE WATER VAPOR IMAGES WERE SHOWING VERY GOOD MID AND
UPPER LEVEL MOISTURE OVER THE SOUTHEAST AND FLORIDA. HIGH PRESSURE
CENTERED OVER ILLINOIS AND INDIANA STRETCHED ACROSS THE SOUTHEAST U.S.
AND INTO NORTH/CENTRAL FLORIDA. LATEST NCEP SURFACE ANALYSIS PLACED A
COLD FRONT OVER THE LAKE OKEECHOBEE AREA OF SOUTHERN FLORIDA.
OVERNIGHT...THE ADVANCING BACK RIGHT QUADRANT OF THE UPPER LEVEL JET
WILL KEEP MID AND HIGH CLOUDINESS OVERNIGHT. RELATIVELY SHALLOW HIGH
PRESSURE FROM THE NORTH WILL MOVE UNDER THE WARMER AND MORE MOIST AIR
MASS THAT WAS BEING TRANSPORTED UP THE PENINSULA BY THE MID LEVEL
SOUTHWEST FLOW. THIS SETS UP LOW CLOUDINESS AND WIDESPREAD RAIN WITH
BURSTS OF MODERATE TO HEAVY RAIN OVER THE SOUTHERN COUNTIES FROM
OSCEOLA AND SOUTH BREVARD SOUTH AND MUCH LIGHTER PRECIPITATION TO THE
NORTH. THE HRRR AND LOCAL WRF MODELS SHOWING SIGNIFICANT ACCUMULATIONS
OVER THE SOUTHERN COASTAL WATERS BRUSHING THE COASTAL AREAS OF MARTIN
SAINT LUCIE COUNTIES OVERNIGHT. WILL HAVE TO WATCH FOR TRAINING OF RAIN
THAT MAY LEAD TO FLOOD ADVISORIES/WARNINGS AFTER MIDNIGHT.
THE LATEST RAP40 RUN MAY BE TOO QUICK IN CLEARING THE FRONT FROM
SOUTHERN FLORIDA BECAUSE THE MID LEVEL/500MB FLOW WAS NEARLY PARALLEL
TO THE SURFACE FRONT. THIS WOULD SUGGEST MORE RAIN OVER THE SOUTHERN
AREAS. THE HIGHEST POP WAS OVER THE SOUTHERN FORECAST AREA FROM SOUTH
BREVARD AND SOUTHERN OSCEOLA SOUTH WITH LOWER POP TO THE NORTH.
FORECAST WINDS BOTH OVER LAND AND THE OCEAN A KNOT OR TWO OFF FROM
OBSERVED WINDS PER THE LATEST REGIONAL WEATHER ROUNDUP.
NO SIGNIFICANT CHANGES TO CURRENT FORECAST PLANNED...FRESHEN WORDING.
.AVIATION...MVFR/VFR CEILINGS AND VISIBILITY KMCO-KTIX NORTH AND
MVFR/IFR CONDITIONS KMLB-KISM SOUTH DUE TO WIDESPREAD LOW CLOUDS AND
OCCASION MODERATE RAIN.
.MARINE...CMAN BUOY AT SAINT AUGUSTINE AND THE NOAA BUOY 20NM EAST OF
PORT CANAVERAL RECORDING NORTHERLY WINDS 17 TO 21 KNOTS. SURFACE
PRESSURE GRADIENT BEGINS STRENGTHENING/TIGHTENING NORTH TO SOUTH AFTER
MIDNIGHT AS HIGH PRESSURE CONTINUES TO BUILDING SOUTH OVER THE COASTAL
WATERS INTERACTS WITH RELATIVELY LOWER PRESSURES OVER SOUTH FLORIDA AND
THE FLORIDA STRAITS.
EXERCISE CAUTION FOR THE EVENING TRANSITIONS TO SMALL CRAFT ADVISORY
SEBASTIAN INLET NORTH FOR THE EARLY MORNING COASTAL WATERS FORECAST.
PREVIOUS AFD ISSUED 321 PM EST THU DEC 3 2015
CURRENT...WEAK FRONTAL BOUNDARY HUNG UP OVER THE
SOUTH-CENTRAL PENINSULA THIS AFTERNOON. DEWPOINT VALUES NORTH OF I-4
HAVE FALLEN INTO THE MIDDLE 50S...WHEREAS LOWER 70 DEGREE READINGS CAN
STILL BE LOCATED OVER THE TREASURE COAST AND OKEECHOBEE COUNTY. A FEW
BREAKS IN THE CLOUDS HAVE BEEN VIEWED ON VISIBLE SATELLITE IMAGERY
ALONG/NORTH OF I-4. NEXRAD 88D SHOWS LIGHT SHOWER ACTIVITY NEAR
MELBOURNE EXTENDING SOUTH AND SOUTHWEST. MOVEMENT OF ACTIVITY IS FROM
THE SOUTHWEST TOWARD THE NORTHEAST AT 15 TO 20 MPH.
TONIGHT...EXPECT MOSTLY CLOUDY CONDITIONS AREAWIDE AS A WEAK FRONTAL
BOUNDARY SLOWLY MOVES SOUTH OF THE AREA COUPLED WITH OCCASIONAL MID-
LEVEL IMPULSES AND DIFFLUENCE ALOFT DUE TO FAVORABLE PROXIMITY TO
UPPER JET. THERE IS LIKELY TO BE A FINE LINE BETWEEN HIGHER
PRECIPITATION CHANCES AND HEAVIER DOWNPOURS ACROSS THE AREA. NEAR
AND NORTH OF THE I-4 CORRIDOR WILL GO WITH A 20 TO 30 PERCENT CHANCE
OF SHOWERS INCREASING GRADUALLY ALL THE WAY UP TO 90 PERCENT OVER
MARTIN COUNTY CLOSER TOWARDS THE FRONT. WILL STILL HOLD ONTO A SCHC
FOR A THUNDERSTORM ACROSS THE TREASURE COAST AND OKEECHOBEE COUNTY.
WHILE DIFFICULT TO PINPOINT EXACT AREAS...IT DOES APPEAR THE FURTHER
SOUTH YOU GO FROM MELBOURNE THE GREATER THE CHANCE FOR SOME HEAVIER
AMOUNTS OF RAINFALL/POTENTIAL TRAINING ECHOES OVERNIGHT. FUTURE
SHIFTS WILL NEED TO MONITOR FOR ANY LOCALIZED FLOODING ISSUES HERE.
WITH CLOUDS AND PRECIPITATION AROUND OVERNIGHT LOWS WILL REMAIN
RELATIVELY MILD ACROSS THE AREA WITH MINS GENERALLY IN THE
60S...PERHAPS LOWER 70 DEGREE READINGS ALONG THE TREASURE COAST AND
UPPER 50S POSSIBLE NORTH OF I-4. EXPECT WINDS THIS EVENING/OVERNIGHT
TO REMAIN FAIRLY ELEVATED...5-10 MPH INTO THE INTERIOR AND 15 MPH
ALONG THE IMMEDIATE SPACE/TREASURE COASTS WITH SOME OCCASIONAL
HIGHER GUSTS.
FRI...FRONTAL BOUNDARY WILL LIE SOUTH OF THE AREA...THOUGH
UNSEASONABLY DEEP MOISTURE WILL STILL BE OVER THE AREA WITH
PRECIPITABLE WATER VALUES NEAR 2 INCHES AROUND LAKE OKEECHOBEE
TAPERING BACK TO 1.50 INCHES NEAR I-4. WILL CONTINUE TO HAVE DECENT
MID/UPPER LEVEL DYNAMICS DRAPED ACROSS THE REGION. PLENTY OF CLOUD
COVER WILL ALSO LINGER WITH A FAIRLY TIGHT PRECIPITATION GRADIENT
OVER THE AREA. WILL CONTINUE WITH 20 TO 30 PERCENT CHANCE OF LIGHT
PRECIPITATION NEAR I-4/NORTHWARD INCREASING AGAIN UP TO 90 PERCENT
ACROSS MARTIN COUNTY. LOCALLY HEAVY RAINFALL REMAINS POSSIBLE
ESPECIALLY ACROSS THE TREASURE COAST. NUISANCE FLOODING OF ROADS/LOW-
LYING AREAS POSSIBLE WHERE ECHOES TRAIN OVER THE SAME LOCATIONS OR
IN PRONE FLOODING SPOTS. WILL CONTINUE WITH A SCHC FOR THUNDERSTORMS
FOR THE TREASURE COAST/OKEECHOBEE COUNTY...THOUGH INSTABILITY WILL
REMAIN LIMITED.
NORTHEAST WINDS WILL AVERAGE 15-20 MPH WITH FREQUENT HIGHER GUSTS ON
THIS DAY. A LAKE WIND ADVISORY MAY NEED TO BE CONSIDERED FOR THIS
DAY BY THE MIDNIGHT FORECAST SHIFT. HIGHS MAY BE A BIT TRICKY
DEPENDING ON PRECIPITATION AND THICKNESS OF CLOUD COVER. WILL GO
WITH L-M/70S I-4 NORTHWARD WITH M70S SOUTH FROM HERE...POTENTIALLY A
FEW U70 DEGREE READINGS IN MARTIN COUNTY.
SAT...WX PATTERN WILL BE SIMILAR TO THE PREVIOUS RAIN/WIND EVENT
THAT AFFECTED CENTRAL FL LAST WEEKEND. THE LIFTING NATURE OF THE
JET WILL CARRY THE BULK OF THE SHORT WAVE ENERGY OFF TO THE
NE...LEAVING THE SRN EXTENSION OF THE TROF WITH LITTLE MORE THAN
ITS OWN MOMENTUM TO BREAK DOWN THE ATLC RIDGE. WITHOUT A CLEAN
FROPA WILL MUCH OF THE AREA WILL BE LEFT UNDER A DEEP MOISTURE
BAND THAT WILL POOL WITHING THE TROF ITSELF.
SCT/NMRS SHRAS WILL CONTINUE WILL INTO THE WEEKEND...BCMG
CATEGORICAL IN THE VCNTY OF LAKE OKEECHOBEE DUE TO THE CLOSER
PROXIMITY TO THE FRONTAL BOUNDARY ITSELF. LIMITED TSTM POTENTIAL AS
H100-H70 WINDS VEER QUICKLY TO THE NE BEHIND THE FRONT...A FLOW
REGIME THAT IS ONE OF THE LEAST FAVORABLE DEEP CONVECTION ACRS
CENTRAL FL. DESPITE A RESPECTABLE MID LVL THERMAL TROF PUSHING ACRS
N FL...THE THERMAL PROFILE IS NOT FAVORABLE FOR DEEP CONVECTION
EITHER AS LAPSE RATES THRU THE H85-H50 LYR ARE EITHER MOIST
ADIABATIC IN THE VCNTY OF THE FRONT OR CAPPED BEHIND IT. WILL KEEP A
SLGT CHC OF TSRAS ALONG THE TREASURE COAST AND ARND LAKE OKEECHOBEE
ON FRI TO ACCOUNT FOR LINGERING SFC/LOW LVL CONVERGENCE IN THE VCNTY
OF THE FRONTAL BNDRY. OTHERWISE...PRECIP WILL BE IN THE FORM OF
LOW/MEDIUM TOPPED SHRAS OR STRATIFORM RAIN.
WEAK COOL AIR ADVECTION BEHIND THE FRONT WILL QUICKLY MODIFY AS THE
BRISK ONSHORE FLOW DEVELOPS. EXTENSIVE CLOUD COVER ALSO WILL LIMIT
SFC HEATING...MAX TEMPS IN THE M/U70S ON SAT...MIN TEMPS L/M60S
INTERIOR AND U60S/L70S ALONG THE COAST. SOME TREASURE COAST SITES
MAY NOT SEE TEMPS FLUCTUATE BY MORE THAN 10F DEGS THRU THE
UPCOMING WEEKEND.
SUN-WED...
DEEP/BRISK ONSHORE FLOW WILL DIMINISH ON SUN THE POST FRONTAL RIDGE
PUSHES OFF THE NEW ENGLAND COAST AND WEAKENS. FRONTAL BNDRY WILL
WASH OUT SOMEWHERE BTWN I-4 AND LAKE OKEECHOBEE...LEAVING ITS
REMNANT MOISTURE BAND TO MEANDER ACRS THE CENTRAL PENINSULA.
H100-H70 MEAN RH VALUES BTWN 80-90PCT WILL REQUIRE POPS TO REMAIN IN
THE FCST THRU MON NIGHT. MILD ONSHORE FLOW WILL KEEP TEMPS ABV AVG
THRU MON...MAXES IN THE M/U70S...MIN TEMPS M/U60S ALONG THE
COAST...L/M60S INTERIOR.
GFS SHOWS A NOR`EASTER FCST TO DVLP OFF THE MID ATLC COAST MON
NIGHT INTO TUE: A NEW SHORT WAVE TROF PUSHES INTO THE MID ATLC AND
INDUCES A CLOSED LOW OUT OF A BROAD COASTAL TROF OVER THE WRN
ATLC. THE SYSTEM MAY PROLONG THE ANTICIPATED HIGH SEAS EVENT AS IT
PUSHES A NRLY SWELL DOWN ITS WRN FLANK...BUT ITS PRIMARY IMPACT
FOR CENTRAL FL WILL BE TO ADD SUFFICIENT TORQUE TO THE NEXT
FRONTAL BOUNDARY TO PUSH IT CLEAR INTO THE FL STRAITS BY DAYBREAK
TUE...BRINGING NOTICEABLY COOLER/DRIER AIR INTO CENTRAL FL. MAX
TEMPS L/M70S WITH A FEW SPOTS N OF I-4 HOLDING IN THE U60S...MIN
TEMPS L/M50S WITH AREAS N OF I-4 DIPPING BLO 50F TUE NIGHT.
&&
.AVIATION...
FEW BREAKS IN CLOUD COVER NORTH OF I-4 THIS AFTERNOON
EXPECTED TO FILL BACK IN THIS EVENING/OVERNIGHT AND THROUGH FRI.
FRONTAL BOUNDARY OVER S/C FL WILL STALL OVER S FL OVERNIGHT/FRI.
COMBO DEEP MOISTURE/IMPULSES ALOFT/JET ENERGY WILL KEEP AN ELEVATED
SHRA/ISOLD TSRA THREAT ACROSS THE TREASURE COAST. MVFR CIGS MOST
AREAS TONIGHT/FRI...WITH IFR CONDS IN PRECIP. N/NNE WINDS TO REMAIN
ELEVATED OVERNIGHT WITH TIGHTER PGRAD ACROSS THE AREA. GUSTY NE
WINDS FORECAST ON FRI AREAWIDE.
&&
.MARINE...
REMAINDER OF AFTERNOON-FRI...WEAK FRONTAL BOUNDARY ACROSS
S/C FLORIDA WILL CONTINUE TO SAG INTO THE SOUTHERN PENINSULA
TONIGHT. NORTHERLY WINDS WILL VEER TO NERLY OVERNIGHT INTO FRI. WIND
SPEEDS WILL INCREASE FROM 15-20 KTS AWAY FROM THE COAST THIS EVENING
TO 25 KTS/GUSTY BY EARLY FRI. CAUTIONARY STATEMENTS WILL BE IN PLACE
OVER THE OPEN ATLC THIS EVENING...NECESSARY NEAR SHORE OVERNIGHT.
SMALL CRAFT ADVISORIES BEGIN ALL LEGS NORTH OF SEBASTIAN INLET AT
09Z/4AM TONIGHT...CONTINUING SOUTHWARD TO JUPITER INLET BY 15Z/10AM
FRI MORNING. SEAS WILL BUILD TO 6 FT WELL OFFSHORE TONIGHT AND UP TO
7 FT TOWARDS DAYBREAK WELL OFFSHORE AND NORTH OF THE CAPE. SEAS WILL
CONTINUE TO BUILD ON FRI THRU THE DAY TO 6-8 FT NEAR SHORE AND 7-9
FT GULF STREAM/OFFSHORE AS VERY HAZARDOUS MARINE CONDS DEVELOP.
SAT-SUN...HAZARDOUS BOATING CONDITIONS THRU THE UPCOMING WEEKEND.
FRONTAL BOUNDARY APPROACHING CENTRAL FL WILL STALL OVER THE S
PENINSULA AS A STRONG HI PRES BUILDS FROM THE MS RIVER VALLEY TO
THE NEW ENGLAND COASTAL WATERS. INTERACTION BTWN THE STALLED
FRONTAL TROF AND THE RIDGE WILL TIGHTEN THE LCL PGRAD ENOUGH TO
SUPPORT A FRESH TO STRONG NE BREEZE. EVENT WILL PEAK SAT AFTN
WITH FREQUENT GUSTS TO GALE FORCE EXPECTED OVER THE OFFSHORE
WATERS. WINDS DIMINISHING TO A MODERATE TO FRESH E/NE BREEZE BY
LATE SUN AFTN...THEN A GENTLE TO MODERATE N/NE BREEZE AFT SUN
NIGHT INTO MON AS THE RIDGE AXIS GRADUALLY WEAKENS. SEAS BUILDING
TO 7-10FT FRI NIGHT. SEAS CONT TO BUILD TO 8-12FT ON SAT BEFORE
SUBSIDING TO 6-9FT SUN NIGHT.
MON-MON NIGHT...BROAD COASTAL TROF WILL DVLP AS THE RIDGE WEAKENS...
EVENTUALLY LEADING TO THE FORMATION OF A WEAK SFC LOW N OF THE
BAHAMAS. WINDS BCMG A GENTLE TO MODERATE N/NW BREEZE. DIMINISHING
SWELL WILL MAINTAIN 6-8FT SEAS THRU THE DAY...SUBSIDING TO 5-7FT
OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 62 73 67 76 / 20 30 20 30
MCO 62 74 64 79 / 30 30 10 30
MLB 69 76 70 78 / 60 60 30 40
VRB 70 76 72 79 / 80 70 50 40
LEE 60 73 61 78 / 20 20 10 20
SFB 62 75 64 78 / 30 30 10 30
ORL 62 75 65 78 / 30 30 10 30
FPR 71 75 72 79 / 80 80 50 40
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FROM 4 AM FRIDAY TO 10 AM EST SUNDAY FOR
FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 0-20 NM-
FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 20-60 NM-
VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 0-20 NM-
VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 20-60 NM.
SMALL CRAFT ADVISORY FROM 10 AM FRIDAY TO 10 AM EST SUNDAY FOR
SEBASTIAN INLET TO JUPITER INLET 0-20 NM-SEBASTIAN INLET TO
JUPITER INLET 20-60 NM.
&&
$$
IMPACT WX...LASCODY
FORECASTS...WIMMER
AREA FORECAST DISCUSSION
NWS MIAMI FL
659 PM EST THU DEC 3 2015
.UPDATE...
FLOOD WATCH WAS ISSUED FOR ALL OF MIAMI-DADE AND BROWARD COUNTIES.
HEAVY RAINFALL IS EXPECTED WITH SHOWERS AND THUNDERSTORMS NOW
MOVING NORTHEAST THIS EVENING. ADDITIONAL HEAVY RAIN WILL DEVELOP
OVERNIGHT AND THROUGH FRIDAY NIGHT ACROSS OF ALL OF SOUTH FLORIDA,
WHICH WILL EXACERBATE CONDITIONS, AS A STALLING COLD FRONT
INTERACTS WITH DEEP TROPICAL MOISTURE. THE FLOOD WATCH MAY NEED TO
BE EXPANDED NORTH AND WEST WITH FUTURE UPDATES.
&&
.AVIATION...
SHOWERS AND STORMS ASSOC WITH LINE NOW MOVING NORTHEAST WILL
AFFECT MIA/OPF/TMB IN THE NEXT FEW HOURS. ADDITIONAL HVY SHOWERS
AND SOME THUNDERSTORMS MAY DEVELOP THROUGH THE TAF PERIOD, AS DEEP
TROPICAL MOISTURE INTERACTS WITH A STALLING COLD FRONT. SOME
IFR/MVFR VIS/CIGS CONDS ARE POSSIBLE AS THIS LINE MOVES THROUGH
THE REGION THIS EVENING WITH GUSTS TO 35 KTS.
&&
.PREV DISCUSSION... /ISSUED 332 PM EST THU DEC 3 2015/
DISCUSSION...
STEADY STREAM OF HEAVY SHOWERS AND EMBEDDED THUNDERSTORMS
FROM CUBA INTO THE KEYS, HAVE HAD A DIFFICULT TIME HOLDING
TOGETHER INTO THE PENINSULA THIS AFTERNOON. DESPITE THIS NEAR TERM
MODELS, ESPECIALLY THE HRRR CONTINUE TO FORECAST THESE CLUSTERS
EVENTUALLY ENTERING SOUTH FLORIDA LATE THIS AFTERNOON. THE HRRR
HAS BEEN FAR TOO AGGRESSIVE THIS AFTERNOON, SO SKEPTICAL OF THIS
ARRIVAL TIME. ABUNDANT CLOUDS HAVE ALSO PREVENTED ANY DEVELOPMENT
DUE TO DAYTIME HEATING SO FAR. UNDER THIS REGIME, TYPICALLY
OFFSHORE HVY SHOWERS AND THUNDERSTORMS HAVE MUCH BETTER SUCCESS
CROSSING LAND DURING THE EVENING AND OVERNIGHT HOURS. HOWEVER,
STILL CAN`T RULE OUT DEVELOPMENT DURING THE DAYTIME HOURS WITH THE
EAST COAST SEABREEZE POTENTIALLY LEADING TO ENOUGH SURFACE
CONVERGENCE/LIFT FOR WET WEATHER ALONG THE EAST COAST METRO. THIS
SEEMS TO BE OCCURRING IN BROWARD/FLL/FXE ATTM AND PARTS OF
INTERIOR MIAMI-DADE.
OVERALL, SOME CHANGES IN THE MODELS. STRONGER WINDS FORECASTED
BY THE MODELS TO AFFECT ALL OF THE EAST COAST AND ATLANTIC
WATERS, NOW ONLY MAKE IT TO PALM BEACH COUNTY. THIS MAY INDICATE
THAT THE WEAKENING COLD FRONT MAY NOT MAKE IT AS FAR SOUTH AS
PREVIOUSLY THOUGHT. SURFACE HIGH PRESSURE IS CENTERED A LITTLE
FURTHER NORTH THROUGH THE MIDDLE ATLANTIC WHICH LEADS TO LESS OF A
PRESSURE GRADIENT ALONG EXTREME SOUTH FL. THUS THERE IS A
DEVELOPING TREND TOWARDS THE HEAVIEST RAINFALL OCCURRING OVER THE
NORTHERN HALF OF THE FORECAST AREA, AS HEAVIEST QPF FROM THE
GFS/ECMWF HAS SHIFTED NORTH. REGARDLESSS, CAN`T PUT MUCH STOCK IN
RUN TO RUN VARIANCES, SO THE HEAVY RAIN THREAT CONTINUES FOR ALL
OF SOUTH FLORIDA.
FOR TONIGHT AND THE FIRST HALF OF FRIDAY, ADDITIONAL FORCING
PROVIDED BY A FEW MIDLEVEL DISTURBANCES AND MORE FAVORABLE
ORIENTATION OF THE UPPER JET, MAY BE THE EXTRA BOOST NEEDED TO
SPARK DEVELOPMENT. WIND FIELD REMAINS FAVORABLE FOR TRAINING AND
BACKBUILDING, ALSO LLVL HELICITY IS FAVORABLE FOR STRONGER STORMS.
WITH THE LACK OF ACTIVITY THUS FAR THIS PM, WILL HOLD OFF ON A
FLOOD WATCH AND CONTINUE TO ASSESS LATER THIS PM. WITH THE SLOWER
PROGRESSION OF THE FRONT, THE GFS DOES INDICATE SOME HEAVIER RAIN
REMAINING ACROSS THE SOUTHERN CWA INTO SATURDAY MORNING, WHEREAS
THE ECMWF HAS BACKED OFF. BOTH MODELS INDICATE A MIDLEVEL
DISTURBANCE CROSSING THE FL STRAITS AND KEYS, CLIPPING EXTREME SE
FL AROUND 6Z SAT. TOUGH TO ASCERTAIN HOW MUCH QPF FROM BOTH MODELS
ARE BEING INFLUENCED BY CONVECTIVE FEEDBACK. STRONGER MIDLEVEL SW
FLOW DOES SEEM TO END FRIDAY EVENING, WHICH WOULD SEEM TO CUTOFF
THE TRANSPORT OF ANOMALOUS MOISTURE ACROSS THE REGION, ALTHOUGH
PWATS WILL STILL BE ELEVATED. BY SATURDAY PM WINDS BECOME EASTERLY
THROUGH H85 AND ONSHORE FLOW WILL BE RESPONSIBLE FOR SHOWERS ALONG
THE EAST COAST. A SIMILAR SETUP IS EXPECTED ON SUNDAY.
DIFFUSE BOUNDARY WAVERS OVER SOUTH FL THROUGH MONDAY. INTO
MIDWEEK, A STRONGER COLD FRONT MOVING THROUGH THE SOUTHEAST CONUS
MAY FINALLY SHOVE THE WEAK BOUNDARY SOUTH USHERING IN DRIER AIR
WITH DEWPOINTS FALLING INTO THE MIDDLE 50S ACROSS THE
INTERIOR/LAKE REGION. HOWEVER, THE GFS IS FASTER WITH THIS
PROGRESSION WHEREAS THE ECMWF LAGS, WITH A WETTER FORECAST FOR
WEDNESDAY. THE GFS IS ALSO MUCH COOLER BEHIND THIS FRONT THAN THE
ECMWF
MARINE...
NUMEROUS SHOWERS AND SOME STRONGER THUNDERSTORMS EXPECTED AS A
WEAK COLD FRONT STALLS INTO SATURDAY AM. LATEST GUIDANCE
INDICATES THAT SMALL CRAFT ADV LEVEL WINDS MAY ONLY MAKE TO THE
ATLANTIC WATERS OFF PALM BEACH COUNTY. WIND SPEEDS MAY STAY AROUND
10 KTS FARTHER SOUTH. WAVE HEIGHTS ALONG THE GULF STREAM THOUGH
ARE STILL EXPECTED TO BE 7 FT AND ABOVE, HIGHEST OFFSHORE PALM
BEACH COUNTY. A WEAK TO MODERATE SWELL WILL ROLL DOWN THE EAST
COAST SAT AND SAT NIGHT. WAVES SUBSIDE SUNDAY NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 70 78 74 80 / 90 90 60 70
FORT LAUDERDALE 69 78 69 79 / 90 80 80 70
MIAMI 71 80 71 81 / 90 80 80 70
NAPLES 67 77 68 82 / 90 90 40 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH THROUGH SATURDAY MORNING FOR FLZ071>074-172>174.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...21/KM
LONG TERM....21/KM
AVIATION...21/KM
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
256 PM CST WED DEC 2 2015
.SHORT TERM...(Tonight)
ISSUED AT 255 PM CST WED DEC 2 2015
Our large upper low was located near Chicago at mid afternoon. Last
of the surface boundaries rotating around the low extended from
about Rantoul to Taylorville on the most recent observations, with
the snow quickly tapering off west of it. Most accumulations have
been minor as temperatures remained above freezing, but some
localized reports around an inch were received mainly along and
north of I-74. Most of this precipitation should be out of the
forecast area by 6 pm, but will carry some low PoP`s near the
Indiana border until about mid evening.
Clearing trends behind the low will be a bit tricky. Large area of
clearing was dropping southward across Iowa with some breaks in west
central and northwest Illinois. However, clouds were still more
extensive across Wisconsin. NAM humidity plots quickly scour this
out over our area by mid evening, but the RAP is much slower with a
more persistent inversion around 2500 feet. Followed a more slow
trend with the sky grids for the cloud breakup, with skies partly
cloudy by midnight.
&&
.LONG TERM...(Thursday through Wednesday)
ISSUED AT 255 PM CST WED DEC 2 2015
The upper low will depart well to the east of Illinois on Thursday,
as ridging builds into the Midwest. Surface high pressure and much
drier air will provide quiet weather for the remainder of the week
and first half of the weekend. Clouds will clear out on Thursday,
with increasing sunshine and southerly winds fueling a warming
trend through Saturday. Highs on Thursday will reach the low to
mid 40s, but temps will climb into the low 50s by Saturday.
A relatively zonal flow will continue into next week, but there
remains differences in timing of the next wave coming out of the
Plains. The ECMWF remains progressive with the next low, bringing it
into IL on Sunday and east of IL by Monday afternoon. The GFS and
Canadian show a slower solution, with somewhat of a cut-off period
for the upper low before it passes by to the south of Illinois late
Monday and Monday night. The forecast for Sunday through Monday
night was left relatively dry, with only slight chance PoPs south of
I-70 on Sunday night, and south of our counties south of highway 50
on Monday. Any precipitation should fall as rain, with the
temperatures remaining at or above normal during that time.
Another trough of low pressure could approach for Wednesday, per the
GFS, but the ECMWF keeps that system north of IL. The overall theme
looks to be for temps at or above normal, with lows in the low to
mid 30s and highs in the upper 40s to around 50 from Monday to
Wednesday next week, along with minimal precipitation.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 1133 AM CST WED DEC 2 2015
Periodic rain and snow showers will continue to move through the
TAF sites through mid afternoon, reducing visibility to 2-3 miles
at times in the heavier showers. Widespread MVFR ceilings will
continue with some local dips into IFR range, mainly at KBMI. Most
of the showers should be out of the TAF sites by 21Z as the
associated upper disturbance swings southeast of the area.
Beyond that time frame, the tricky element will be with the
ceilings. Visible satellite imagery showing a large shield of MVFR
clouds all the way into northern Wisconsin, but there is a fair
amount of breaks in the clouds wrapping around an upper low that
is currently in northern Illinois. Have slowed the clearing trend
in the previous TAF set by a few hours, with the RAP model showing
a fairly stout inversion around 2500 feet, although the NAM breaks
through it much faster.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...Shimon
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
210 PM CST WED DEC 2 2015
.SHORT TERM...
329 AM CST
THROUGH THURSDAY...
THE SECOND SNOW OF THE SEASON IS UNDERWAY THIS MORNING. WHILE MUCH
LESS IN TOTAL AMOUNT THAN THE NOVEMBER 20-21 EVENT...THE TIMING IS
PROBLEMATIC. HAVE REFINED HOURLY FORECASTS TO GIVE DETAIL OF
EXPECTED MODERATE/HEAVIER SNOWFALL TIMING AS OBSERVATIONAL TRENDS
SHOW THEIR HAND...THOUGH THIS IS STILL LARGELY IN AGREEMENT WITH
PREVIOUS FORECAST. HAVE INCREASED FORECAST SNOWFALL TOTALS ON
GRASS SURFACES INTO THE 1 TO 2 INCH CATEGORY FOR MANY WITH
ISOLATED HIGHER AMOUNTS PROBABLE GIVEN THE SLOW MOVING NATURE OF
THE MODEST RATES. CONTINUE WITH MESSAGING IN THE SPS AND
GRAPHICAL NOWCASTS TOWARD HIGHEST IMPACTS THROUGH 10 AM AND THUS
IMPACTING COMMUTERS.
THE BROAD BUT STRONG UPPER LOW IS GYRATING OVER THE
WI/MN/IA/NORTHERN IL REGION THIS MORNING. A NOTEWORTHY EMBEDDED
VORTICITY CENTER IS LIFTING NORTHEASTWARD OVER NORTHERN MO THIS
MORNING WHICH WILL MOVE OVER NORTHEAST ILLINOIS AROUND DAYBREAK. ON
THE LEADING EDGE OF THIS IS A FAVORED AREA FOR FOCUSED MORE INTENSE
ASCENT WHICH WILL OVERRIDE THE ONGOING PRECIPITATION...MAINLY
SNOW...SPREADING EAST ACROSS NORTHERN ILLINOIS AS OF 315 AM. THIS
MORE INTENSE SYNOPTIC LIFT LOOKS TO COINCIDE WITH THE LOWER TO
MID-LEVEL TEMPERATURE GRADIENT WHICH IS TIGHTENING AND ADDING
RESPONSIVE MESOSCALE LIFT...ESPECIALLY WITH CONDITIONAL
INSTABILITY ABOVE THAT PER THE RAP MODEL. ALL THIS POINTS TOWARD
AN AREA/BAND OF SNOW TO INTENSIFY ACROSS NORTHEAST
ILLINOIS...INCLUDING MUCH OF THE CHICAGO METRO AREA THROUGH 730 AM
OR SO. HIGH-RESOLUTION MODELS GENERALLY SUPPORT THIS...SHIFTING
INTO NORTHWEST INDIANA BUT LIKELY WEAKENING SOME DURING THE 7 TO
10 AM TIME OR SO. SOME OF THIS PRECIPITATION IN NORTHWEST INDIANA
WILL LIKELY BE RAIN OR A MIX AT ONSET...BUT SHOULD SHIFT QUICKLY
TO SNOW AS DIABATIC COOLING OCCURS.
WEBCAM IMAGERY AND A FEW EARLY MORNING REPORTS ARE INDICATING QUICK
ACCUMULATIONS IN EXCESS OF AN INCH ON GRASS. WHILE PAVEMENT HAS BEEN
RELATIVELY FREE OF SNOW ACCUMULATION THUS FAR...THE HEAVIER RATES
WILL COMPENSATE FOR THAT WITH LIKELY SOME LIGHT SLUSHY
ACCUMULATION IN PLACES. THIS MAY BE A LITTLE HARDER TO COME BY IN
DOWNTOWN CHICAGO WHERE OBSERVATIONS STILL INDICATE AIR
TEMPERATURES OF 37-38 DEGREES AS OF 315 AM.
BEHIND THIS SNOW AREA...SNOW SHOWERS UNDER THE COLD POCKET ALOFT
AND OTHER EMBEDDED BUT WEAKER VORTICITY MAXIMAS WILL MOVE EASTWARD
INTO NORTH CENTRAL ILLINOIS THIS MORNING AND ACROSS THE REST OF
THE AREA. COVERAGE OF THESE SNOW SHOWERS IS LIKELY TO UNDULATE
SOME...BUT HAVE BASICALLY KEPT HIGH PROBABILITIES FOR SNOW THROUGH
EARLY AFTERNOON ACROSS NORTH CENTRAL ILLINOIS AND MUCH OF THE DAY
FOR EASTWARD...THOUGH THE DEFINITE POPS AND HEAVIER WORDING IS IN
THE EARLY MORNING.
TEMPERATURES WILL LIKELY TRY TO REBOUND A FEW DEGREES LATE THIS
MORNING AND AFTERNOON...WHICH MAY MELT SOME OF THE SNOW THAT
FALLS. THE TEMPERATURE FORECAST FOR TONIGHT IS CHALLENGING AS
THERE ARE LIKELY TO BE HOLES IN THE CLOUD COVER YET THE CYCLONIC
FLOW WILL INEVITABLY KEEP SOME LARGE AREAS OF CLOUDS TOO. FOR
THOSE LOCATIONS THAT CLEAR...MID 20S LOOK LIKE A GOOD BET.
LINGERING CLOUDS THURSDAY MORNING SHOULD ABATE BY THURSDAY
AFTERNOON.
MTF
&&
.LONG TERM...
THURSDAY NIGHT THROUGH WEDNESDAY...
210 PM...GENERALLY QUIET WEATHER EXPECTED THROUGH THE PERIOD.
HIGH TEMPS WILL MODERATE INTO THE 40S ON FRIDAY AND POSSIBLY INTO
THE LOWER 50S ON SATURDAY...BUT THIS WILL BE AFTER LOWS IN THE 20S
BOTH MORNINGS. A WEAKENING UPPER TROUGH WILL MOVE ACROSS THE AREA
SUNDAY INTO SUNDAY NIGHT WHICH APPEARS TO ONLY INCREASE CLOUD
COVER. ECMWF HOWEVER HAS MUCH MORE QPF BACK ACROSS IA/MN/WI SUNDAY
AND TRIES TO WORK THIS INTO THE AREA SUNDAY NIGHT. HAVE CONTINUED
WITH A DRY FORECAST BUT AS THIS TIME PERIOD APPROACHES...COULD BE
SOME LIGHT SHOWERS POSSIBLE...ESPECIALLY WESTERN AREAS. WITH THE
EXPECTED CLOUD COVER ON SUNDAY...HIGH TEMPS MAY BE A BIT LOWER
THAN SATURDAY...PERHAPS ONLY MID 40S. CLOSED UPPER LOW THEN
APPEARS TO JUST MISS THE CWA TO THE SOUTH EARLY NEXT WEEK WITH
ABOVE NORMAL TEMPS EXPECTED THRU THE MIDDLE OF NEXT WEEK. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* SNOW SHOWERS GRADUALLY ENDING THIS AFTERNOON.
* MVFR CIGS AT TIMES THIS AFTERNOON.
* NW WIND GUSTS TO 20 KT LATE THIS AFTERNOON/EARLY EVENING.
* LOW CLOUDS AROUND 1,000 FT LOOK TO RETURN MID TO LATE THURSDAY
MORNING.
KJB
//DISCUSSION...UPDATED 18Z...
A STORM SYSTEM WILL MOVE OVER THE AREA THROUGH THE AFTERNOON. THIS
WILL CONTINUE TO GENERATE MAINLY LIGHT SNOW SHOWERS THROUGH MID
AFTERNOON...OVER MAINLY THE EASTERN TERMINAL SITES. OCCASIONAL IFR
VIS DOWN TO AROUND 1 1/2 SM AND CIGS AROUND...OR JUST BELOW 1,000 FT
ARE EXPECTED...BEFORE CONDITIONS IMPROVE LATER THIS AFTERNOON. WINDS
WILL ALSO BECOME A BIT GUSTY OUT OF THE NORTHWEST LATER THIS
AFTERNOON AS A SURFACE TROUGH MOVES OVER THE AREA. CIGS LOOK TO
IMPROVE TO VFR...IF NOT SCATTER OUT ALL TOGETHER FOR A PERIOD
TONIGHT. HOWEVER...ADDITIONAL LOW CLOUDS...CURRENTLY OVER WESTERN
IOWA...LOOK TO MOVE BACK OVER OUR AREA BY MID TO LATE THURSDAY
MORNING. IT APPEARS THAT THESE CIGS COULD BE DOWN AROUND 1,000 FT.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM-HIGH WITH CIG FORECAST TODAY.
* MEDIUM ON WIND GUSTS THIS AFTERNOON/EVENING.
* MEDIUM WITH LOW CIGS RETURNING ON THURSDAY.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
FRIDAY THROUGH TUESDAY...VFR WITH GENERALLY SW WINDS. WINDS MAY
SHIFT TO VARIABLE/EASTERLY ON MONDAY.
KMD
&&
.MARINE...
210 PM...WEAK LOW PRESSURE OVER WESTERN MICHIGAN WILL MOVE EAST
AND MERGE WITH A STRONGER LOW PRESSURE MOVING NORTHEAST ALONG THE
ATLANTIC COAST THIS EVENING. LARGE HIGH PRESSURE WILL MOVE ACROSS
THE PLAINS TONIGHT AND STRENGTHEN AS IT MOVES ACROSS THE OHIO
VALLEY THURSDAY NIGHT. THIS HIGH WILL STRENGTHEN FURTHER REACHING
THE MID ATLANTIC REGION FRIDAY. NORTHWEST WINDS TONIGHT WILL TURN
MORE WESTERLY THURSDAY AND THEN SOUTHWESTERLY FRIDAY INTO
SATURDAY. THE GRADIENT TIGHTENS INTO SATURDAY WHEN 30KTS WILL BE
POSSIBLE OVER NORTHERN PORTIONS OF THE LAKE. ANOTHER HIGH WILL
MOVE ACROSS THE LAKES REGION SUNDAY INTO MONDAY WITH WINDS TURNING
SOUTHERLY ON THE BACK SIDE OF THIS HIGH EARLY NEXT WEEK. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
151 PM CST WED DEC 2 2015
.SHORT TERM...
329 AM CST
THROUGH THURSDAY...
THE SECOND SNOW OF THE SEASON IS UNDERWAY THIS MORNING. WHILE MUCH
LESS IN TOTAL AMOUNT THAN THE NOVEMBER 20-21 EVENT...THE TIMING IS
PROBLEMATIC. HAVE REFINED HOURLY FORECASTS TO GIVE DETAIL OF
EXPECTED MODERATE/HEAVIER SNOWFALL TIMING AS OBSERVATIONAL TRENDS
SHOW THEIR HAND...THOUGH THIS IS STILL LARGELY IN AGREEMENT WITH
PREVIOUS FORECAST. HAVE INCREASED FORECAST SNOWFALL TOTALS ON
GRASS SURFACES INTO THE 1 TO 2 INCH CATEGORY FOR MANY WITH
ISOLATED HIGHER AMOUNTS PROBABLE GIVEN THE SLOW MOVING NATURE OF
THE MODEST RATES. CONTINUE WITH MESSAGING IN THE SPS AND
GRAPHICAL NOWCASTS TOWARD HIGHEST IMPACTS THROUGH 10 AM AND THUS
IMPACTING COMMUTERS.
THE BROAD BUT STRONG UPPER LOW IS GYRATING OVER THE
WI/MN/IA/NORTHERN IL REGION THIS MORNING. A NOTEWORTHY EMBEDDED
VORTICITY CENTER IS LIFTING NORTHEASTWARD OVER NORTHERN MO THIS
MORNING WHICH WILL MOVE OVER NORTHEAST ILLINOIS AROUND DAYBREAK. ON
THE LEADING EDGE OF THIS IS A FAVORED AREA FOR FOCUSED MORE INTENSE
ASCENT WHICH WILL OVERRIDE THE ONGOING PRECIPITATION...MAINLY
SNOW...SPREADING EAST ACROSS NORTHERN ILLINOIS AS OF 315 AM. THIS
MORE INTENSE SYNOPTIC LIFT LOOKS TO COINCIDE WITH THE LOWER TO
MID-LEVEL TEMPERATURE GRADIENT WHICH IS TIGHTENING AND ADDING
RESPONSIVE MESOSCALE LIFT...ESPECIALLY WITH CONDITIONAL
INSTABILITY ABOVE THAT PER THE RAP MODEL. ALL THIS POINTS TOWARD
AN AREA/BAND OF SNOW TO INTENSIFY ACROSS NORTHEAST
ILLINOIS...INCLUDING MUCH OF THE CHICAGO METRO AREA THROUGH 730 AM
OR SO. HIGH-RESOLUTION MODELS GENERALLY SUPPORT THIS...SHIFTING
INTO NORTHWEST INDIANA BUT LIKELY WEAKENING SOME DURING THE 7 TO
10 AM TIME OR SO. SOME OF THIS PRECIPITATION IN NORTHWEST INDIANA
WILL LIKELY BE RAIN OR A MIX AT ONSET...BUT SHOULD SHIFT QUICKLY
TO SNOW AS DIABATIC COOLING OCCURS.
WEBCAM IMAGERY AND A FEW EARLY MORNING REPORTS ARE INDICATING QUICK
ACCUMULATIONS IN EXCESS OF AN INCH ON GRASS. WHILE PAVEMENT HAS BEEN
RELATIVELY FREE OF SNOW ACCUMULATION THUS FAR...THE HEAVIER RATES
WILL COMPENSATE FOR THAT WITH LIKELY SOME LIGHT SLUSHY
ACCUMULATION IN PLACES. THIS MAY BE A LITTLE HARDER TO COME BY IN
DOWNTOWN CHICAGO WHERE OBSERVATIONS STILL INDICATE AIR
TEMPERATURES OF 37-38 DEGREES AS OF 315 AM.
BEHIND THIS SNOW AREA...SNOW SHOWERS UNDER THE COLD POCKET ALOFT
AND OTHER EMBEDDED BUT WEAKER VORTICITY MAXIMAS WILL MOVE EASTWARD
INTO NORTH CENTRAL ILLINOIS THIS MORNING AND ACROSS THE REST OF
THE AREA. COVERAGE OF THESE SNOW SHOWERS IS LIKELY TO UNDULATE
SOME...BUT HAVE BASICALLY KEPT HIGH PROBABILITIES FOR SNOW THROUGH
EARLY AFTERNOON ACROSS NORTH CENTRAL ILLINOIS AND MUCH OF THE DAY
FOR EASTWARD...THOUGH THE DEFINITE POPS AND HEAVIER WORDING IS IN
THE EARLY MORNING.
TEMPERATURES WILL LIKELY TRY TO REBOUND A FEW DEGREES LATE THIS
MORNING AND AFTERNOON...WHICH MAY MELT SOME OF THE SNOW THAT
FALLS. THE TEMPERATURE FORECAST FOR TONIGHT IS CHALLENGING AS
THERE ARE LIKELY TO BE HOLES IN THE CLOUD COVER YET THE CYCLONIC
FLOW WILL INEVITABLY KEEP SOME LARGE AREAS OF CLOUDS TOO. FOR
THOSE LOCATIONS THAT CLEAR...MID 20S LOOK LIKE A GOOD BET.
LINGERING CLOUDS THURSDAY MORNING SHOULD ABATE BY THURSDAY
AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
THURSDAY NIGHT THROUGH TUESDAY...
THE PATTERN FOR LATE IN THE WEEK THROUGH EARLY NEXT WEEK CONTINUES
TO LOOK MAINLY DRY AND MILD...WITH HIGHEST CONFIDENCE IN THE
MILD AIR ON SATURDAY WHERE HIGHS COULD REACH LOWER TO MID 50S
AREAWIDE. WHILE NO GUIDANCE HAS THIS IN THEIR SURFACE TEMPERATURE
PREDICTIONS...CLIMATOLOGY WOULD SUPPORT SUCH READINGS GIVEN THEIR
FORECAST 925MB TEMPERATURES AND DEGREE OF ANOMALIES.
THE 00Z GFS AND EC BOTH INDICATE A WEAK BOUNDARY SINKING SOUTHWARD
NEAR OR INTO THE AREA ON SUNDAY...ALONG WITH ANOTHER SLOW-MOVING BUT
MUCH WEAKER/SMALLER UPPER LOW TO THE NEARBY SOUTHWEST. TOGETHER
THIS COULD BRING SOME CLOUDS AND KEEP TEMPERATURES A LITTLE COOLER
THAN SATURDAY AND HAVE FAVORED THAT ROUTE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* SNOW SHOWERS GRADUALLY ENDING THIS AFTERNOON.
* MVFR CIGS AT TIMES THIS AFTERNOON.
* NW WIND GUSTS TO 20 KT LATE THIS AFTERNOON/EARLY EVENING.
* LOW CLOUDS AROUND 1,000 FT LOOK TO RETURN MID TO LATE THURSDAY
MORNING.
KJB
//DISCUSSION...UPDATED 18Z...
A STORM SYSTEM WILL MOVE OVER THE AREA THROUGH THE AFTERNOON. THIS
WILL CONTINUE TO GENERATE MAINLY LIGHT SNOW SHOWERS THROUGH MID
AFTERNOON...OVER MAINLY THE EASTERN TERMINAL SITES. OCCASIONAL IFR
VIS DOWN TO AROUND 1 1/2 SM AND CIGS AROUND...OR JUST BELOW 1,000 FT
ARE EXPECTED...BEFORE CONDITIONS IMPROVE LATER THIS AFTERNOON. WINDS
WILL ALSO BECOME A BIT GUSTY OUT OF THE NORTHWEST LATER THIS
AFTERNOON AS A SURFACE TROUGH MOVES OVER THE AREA. CIGS LOOK TO
IMPROVE TO VFR...IF NOT SCATTER OUT ALL TOGETHER FOR A PERIOD
TONIGHT. HOWEVER...ADDITIONAL LOW CLOUDS...CURRENTLY OVER WESTERN
IOWA...LOOK TO MOVE BACK OVER OUR AREA BY MID TO LATE THURSDAY
MORNING. IT APPEARS THAT THESE CIGS COULD BE DOWN AROUND 1,000 FT.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM-HIGH WITH CIG FORECAST TODAY.
* MEDIUM ON WIND GUSTS THIS AFTERNOON/EVENING.
* MEDIUM WITH LOW CIGS RETURNING ON THURSDAY.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
FRIDAY THROUGH TUESDAY...VFR WITH GENERALLY SW WINDS. WINDS MAY
SHIFT TO VARIABLE/EASTERLY ON MONDAY.
KMD
&&
.MARINE...
108 AM CST
A LOW PRESSURE TROUGH EXTENDS FROM THE LOW CENTER ACROSS LAKE
SUPERIOR SOUTHWESTWARD TO THE UPPER MISSISSIPPI VALLEY. THE TROUGH
AXIS WILL CROSS LAKE MICHIGAN THIS MORNING...WITH A COLD FRONT
SPREADING ACROSS THE LAKE THROUGH THE DAY. WINDS QUICKLY SHIFT TO
NORTHWESTERLY BEHIND THE FRONT AND INCREASE THIS
AFTERNOON...ESPECIALLY OVER THE SOUTH HALF. WITH THE DEVELOPMENT
OF A SECONDARY LOW CENTER OVER THE LAKE...MODEST PRESSURE RISES AS
THE LOW DEPARTS COULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS OVER
THE INDIANA NEARSHORE WATERS. HIGH PRESSURE WILL MOVE INTO THE
OHIO VALLEY LATER THURSDAY INTO FRIDAY WITH THE RIDGE AXIS MOVING
OVER THE LAKE FRIDAY. THE HIGH STRENGTHENS OVER THE EASTERN U.S.
WHILE LOW PRESSURE SKIRTS EAST THROUGH HUDSON BAY LATER IN THE
WEEKEND. THE HIGH WILL EXPAND OVER THE LAKE ON MONDAY. THIS
PATTERN SUGGESTS AN EXTENDED PERIOD OF LIGHTER TO MODEST SOUTH-
SOUTHWEST WINDS AND RELATIVELY BENIGN CONDITIONS FOR DECEMBER
AFTER TODAYS COLD FRONT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1133 AM CST WED DEC 2 2015
.MESOSCALE DISCUSSION...
600 AM CST
SNOW OVER NORTHEAST ILLINOIS HAS INTENSIFIED PRETTY MUCH AS
ANTICIPATED. SOME TEMPORARY ONE HALF MILE VISIBILITY HAS BEEN
REPORTED AND CONTINUE TO EXPECT THAT ACROSS THE CHICAGO METRO AT
TIMES THROUGH 730 AM. SNOWFALL IS ACCUMULATING READILY ON GRASSY
SURFACES WITH STILL NOT MUCH HAVING BEEN REPORTED ON PAVED
SURFACES...INCLUDING UP NEAR WOODSTOCK WHERE AN ISOLATED TOTAL OF
3.5 INCHES WAS REPORTED FROM ONE OF OUR OBSERVERS.
THESE ISOLATED HIGHER TOTALS IN EXCESS OF TWO INCHES WILL REMAIN
POSSIBLE NOT ONLY AIDED BY HEAVIER RATES BUT ALSO LARGER
SNOWFLAKES. A RECENT AIRCRAFT SOUNDING FROM ORD INDICATED WIND
SPEEDS LIGHTER THAN 10 KT ALL THE WAY UP TO 3500 FT INDICATING
LITTLE IN THE WAY OF FRAGMENTING ALLOWING FOR LARGER FLAKES TO
REACH THE GROUND...WHICH WE OBSERVED HERE AT THE WFO FOR A PERIOD.
THE SOUNDING ALSO INDICATED A PRONOUNCED ISOTHERMAL PROFILE NEAR
-5C...LIKELY RIGHT WITHIN THE FRONTOGENETIC LAYER...AND THIS IS
ALL UNDERNEATH A SATURATED DENDRITIC GROWTH AREA. ALTOGETHER THIS
IS ALLOWING FOR LARGER FLAKES TO BE MIXED IN OR EVEN BE
DOMINANT...ALLOWING FOR QUICKER RATES AND SOME HIGHER
ACCUMULATIONS. WHILE PAVEMENT ACCUMULATION WILL BE MUCH LESS WITH
STILL ONLY SOME LIGHT SLUSH ANTICIPATED /AND HARDLY ANY REPORTED
YET/...THE TIMING CONTINUES TO IMPACT THE COMMUTE WITH LOW
VISIBILITY...SO WE CONTINUE THAT MESSAGE WITHIN OUR FORECAST.
MTF
&&
.SHORT TERM...
329 AM CST
THROUGH THURSDAY...
THE SECOND SNOW OF THE SEASON IS UNDERWAY THIS MORNING. WHILE MUCH
LESS IN TOTAL AMOUNT THAN THE NOVEMBER 20-21 EVENT...THE TIMING IS
PROBLEMATIC. HAVE REFINED HOURLY FORECASTS TO GIVE DETAIL OF
EXPECTED MODERATE/HEAVIER SNOWFALL TIMING AS OBSERVATIONAL TRENDS
SHOW THEIR HAND...THOUGH THIS IS STILL LARGELY IN AGREEMENT WITH
PREVIOUS FORECAST. HAVE INCREASED FORECAST SNOWFALL TOTALS ON
GRASS SURFACES INTO THE 1 TO 2 INCH CATEGORY FOR MANY WITH
ISOLATED HIGHER AMOUNTS PROBABLE GIVEN THE SLOW MOVING NATURE OF
THE MODEST RATES. CONTINUE WITH MESSAGING IN THE SPS AND
GRAPHICAL NOWCASTS TOWARD HIGHEST IMPACTS THROUGH 10 AM AND THUS
IMPACTING COMMUTERS.
THE BROAD BUT STRONG UPPER LOW IS GYRATING OVER THE
WI/MN/IA/NORTHERN IL REGION THIS MORNING. A NOTEWORTHY EMBEDDED
VORTICITY CENTER IS LIFTING NORTHEASTWARD OVER NORTHERN MO THIS
MORNING WHICH WILL MOVE OVER NORTHEAST ILLINOIS AROUND DAYBREAK. ON
THE LEADING EDGE OF THIS IS A FAVORED AREA FOR FOCUSED MORE INTENSE
ASCENT WHICH WILL OVERRIDE THE ONGOING PRECIPITATION...MAINLY
SNOW...SPREADING EAST ACROSS NORTHERN ILLINOIS AS OF 315 AM. THIS
MORE INTENSE SYNOPTIC LIFT LOOKS TO COINCIDE WITH THE LOWER TO
MID-LEVEL TEMPERATURE GRADIENT WHICH IS TIGHTENING AND ADDING
RESPONSIVE MESOSCALE LIFT...ESPECIALLY WITH CONDITIONAL
INSTABILITY ABOVE THAT PER THE RAP MODEL. ALL THIS POINTS TOWARD
AN AREA/BAND OF SNOW TO INTENSIFY ACROSS NORTHEAST
ILLINOIS...INCLUDING MUCH OF THE CHICAGO METRO AREA THROUGH 730 AM
OR SO. HIGH-RESOLUTION MODELS GENERALLY SUPPORT THIS...SHIFTING
INTO NORTHWEST INDIANA BUT LIKELY WEAKENING SOME DURING THE 7 TO
10 AM TIME OR SO. SOME OF THIS PRECIPITATION IN NORTHWEST INDIANA
WILL LIKELY BE RAIN OR A MIX AT ONSET...BUT SHOULD SHIFT QUICKLY
TO SNOW AS DIABATIC COOLING OCCURS.
WEBCAM IMAGERY AND A FEW EARLY MORNING REPORTS ARE INDICATING QUICK
ACCUMULATIONS IN EXCESS OF AN INCH ON GRASS. WHILE PAVEMENT HAS BEEN
RELATIVELY FREE OF SNOW ACCUMULATION THUS FAR...THE HEAVIER RATES
WILL COMPENSATE FOR THAT WITH LIKELY SOME LIGHT SLUSHY
ACCUMULATION IN PLACES. THIS MAY BE A LITTLE HARDER TO COME BY IN
DOWNTOWN CHICAGO WHERE OBSERVATIONS STILL INDICATE AIR
TEMPERATURES OF 37-38 DEGREES AS OF 315 AM.
BEHIND THIS SNOW AREA...SNOW SHOWERS UNDER THE COLD POCKET ALOFT
AND OTHER EMBEDDED BUT WEAKER VORTICITY MAXIMAS WILL MOVE EASTWARD
INTO NORTH CENTRAL ILLINOIS THIS MORNING AND ACROSS THE REST OF
THE AREA. COVERAGE OF THESE SNOW SHOWERS IS LIKELY TO UNDULATE
SOME...BUT HAVE BASICALLY KEPT HIGH PROBABILITIES FOR SNOW THROUGH
EARLY AFTERNOON ACROSS NORTH CENTRAL ILLINOIS AND MUCH OF THE DAY
FOR EASTWARD...THOUGH THE DEFINITE POPS AND HEAVIER WORDING IS IN
THE EARLY MORNING.
TEMPERATURES WILL LIKELY TRY TO REBOUND A FEW DEGREES LATE THIS
MORNING AND AFTERNOON...WHICH MAY MELT SOME OF THE SNOW THAT
FALLS. THE TEMPERATURE FORECAST FOR TONIGHT IS CHALLENGING AS
THERE ARE LIKELY TO BE HOLES IN THE CLOUD COVER YET THE CYCLONIC
FLOW WILL INEVITABLY KEEP SOME LARGE AREAS OF CLOUDS TOO. FOR
THOSE LOCATIONS THAT CLEAR...MID 20S LOOK LIKE A GOOD BET.
LINGERING CLOUDS THURSDAY MORNING SHOULD ABATE BY THURSDAY
AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
THURSDAY NIGHT THROUGH TUESDAY...
THE PATTERN FOR LATE IN THE WEEK THROUGH EARLY NEXT WEEK CONTINUES
TO LOOK MAINLY DRY AND MILD...WITH HIGHEST CONFIDENCE IN THE
MILD AIR ON SATURDAY WHERE HIGHS COULD REACH LOWER TO MID 50S
AREAWIDE. WHILE NO GUIDANCE HAS THIS IN THEIR SURFACE TEMPERATURE
PREDICTIONS...CLIMATOLOGY WOULD SUPPORT SUCH READINGS GIVEN THEIR
FORECAST 925MB TEMPERATURES AND DEGREE OF ANOMALIES.
THE 00Z GFS AND EC BOTH INDICATE A WEAK BOUNDARY SINKING SOUTHWARD
NEAR OR INTO THE AREA ON SUNDAY...ALONG WITH ANOTHER SLOW-MOVING BUT
MUCH WEAKER/SMALLER UPPER LOW TO THE NEARBY SOUTHWEST. TOGETHER
THIS COULD BRING SOME CLOUDS AND KEEP TEMPERATURES A LITTLE COOLER
THAN SATURDAY AND HAVE FAVORED THAT ROUTE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SNOW SHOWERS THROUGH MID AFTERNOON WITH IFR VIS LIKELY AT
TIMES.
* LOW MVFR TO IFR CIGS INTO EARLY AFTERNOON.
* NW WIND GUSTS TO 20 KT LATE THIS AFTERNOON/EARLY EVENING.
* LOW CLOUDS AROUND 1,000 FT LOOK TO RETURN MID TO LATE THURSDAY
MORNING.
KJB
//DISCUSSION...UPDATED 18Z...
A STORM SYSTEM WILL MOVE OVER THE AREA THROUGH THE AFTERNOON. THIS
WILL CONTINUE TO GENERATE MAINLY LIGHT SNOW SHOWERS THROUGH MID
AFTERNOON...OVER MAINLY THE EASTERN TERMINAL SITES. OCCASIONAL IFR
VIS DOWN TO AROUND 1 1/2 SM AND CIGS AROUND...OR JUST BELOW 1,000 FT
ARE EXPECTED...BEFORE CONDITIONS IMPROVE LATER THIS AFTERNOON. WINDS
WILL ALSO BECOME A BIT GUSTY OUT OF THE NORTHWEST LATER THIS
AFTERNOON AS A SURFACE TROUGH MOVES OVER THE AREA. CIGS LOOK TO
IMPROVE TO VFR...IF NOT SCATTER OUT ALL TOGETHER FOR A PERIOD
TONIGHT. HOWEVER...ADDITIONAL LOW CLOUDS...CURRENTLY OVER WESTERN
IOWA...LOOK TO MOVE BACK OVER OUR AREA BY MID TO LATE THURSDAY
MORNING. IT APPEARS THAT THESE CIGS COULD BE DOWN AROUND 1,000 FT.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH IN OCCASIONAL IFR VSBY IN SNOW SHOWERS TODAY.
* MEDIUM-HIGH IN LOW MVFR TO IFR CIGS INTO EARLY AFTERNOON.
* MEDIUM ON WIND GUSTS THIS AFTERNOON/EVENING.
* MEDIUM WITH LOW CIGS RETURNING ON THURSDAY.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
FRIDAY THROUGH TUESDAY...VFR WITH GENERALLY SW WINDS. WINDS MAY
SHIFT TO VARIABLE/EASTERLY ON MONDAY.
KMD
&&
.MARINE...
108 AM CST
A LOW PRESSURE TROUGH EXTENDS FROM THE LOW CENTER ACROSS LAKE
SUPERIOR SOUTHWESTWARD TO THE UPPER MISSISSIPPI VALLEY. THE TROUGH
AXIS WILL CROSS LAKE MICHIGAN THIS MORNING...WITH A COLD FRONT
SPREADING ACROSS THE LAKE THROUGH THE DAY. WINDS QUICKLY SHIFT TO
NORTHWESTERLY BEHIND THE FRONT AND INCREASE THIS
AFTERNOON...ESPECIALLY OVER THE SOUTH HALF. WITH THE DEVELOPMENT
OF A SECONDARY LOW CENTER OVER THE LAKE...MODEST PRESSURE RISES AS
THE LOW DEPARTS COULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS OVER
THE INDIANA NEARSHORE WATERS. HIGH PRESSURE WILL MOVE INTO THE
OHIO VALLEY LATER THURSDAY INTO FRIDAY WITH THE RIDGE AXIS MOVING
OVER THE LAKE FRIDAY. THE HIGH STRENGTHENS OVER THE EASTERN U.S.
WHILE LOW PRESSURE SKIRTS EAST THROUGH HUDSON BAY LATER IN THE
WEEKEND. THE HIGH WILL EXPAND OVER THE LAKE ON MONDAY. THIS
PATTERN SUGGESTS AN EXTENDED PERIOD OF LIGHTER TO MODEST SOUTH-
SOUTHWEST WINDS AND RELATIVELY BENIGN CONDITIONS FOR DECEMBER
AFTER TODAYS COLD FRONT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1013 AM CST WED DEC 2 2015
.MESOSCALE DISCUSSION...
600 AM CST
SNOW OVER NORTHEAST ILLINOIS HAS INTENSIFIED PRETTY MUCH AS
ANTICIPATED. SOME TEMPORARY ONE HALF MILE VISIBILITY HAS BEEN
REPORTED AND CONTINUE TO EXPECT THAT ACROSS THE CHICAGO METRO AT
TIMES THROUGH 730 AM. SNOWFALL IS ACCUMULATING READILY ON GRASSY
SURFACES WITH STILL NOT MUCH HAVING BEEN REPORTED ON PAVED
SURFACES...INCLUDING UP NEAR WOODSTOCK WHERE AN ISOLATED TOTAL OF
3.5 INCHES WAS REPORTED FROM ONE OF OUR OBSERVERS.
THESE ISOLATED HIGHER TOTALS IN EXCESS OF TWO INCHES WILL REMAIN
POSSIBLE NOT ONLY AIDED BY HEAVIER RATES BUT ALSO LARGER
SNOWFLAKES. A RECENT AIRCRAFT SOUNDING FROM ORD INDICATED WIND
SPEEDS LIGHTER THAN 10 KT ALL THE WAY UP TO 3500 FT INDICATING
LITTLE IN THE WAY OF FRAGMENTING ALLOWING FOR LARGER FLAKES TO
REACH THE GROUND...WHICH WE OBSERVED HERE AT THE WFO FOR A PERIOD.
THE SOUNDING ALSO INDICATED A PRONOUNCED ISOTHERMAL PROFILE NEAR
-5C...LIKELY RIGHT WITHIN THE FRONTOGENETIC LAYER...AND THIS IS
ALL UNDERNEATH A SATURATED DENDRITIC GROWTH AREA. ALTOGETHER THIS
IS ALLOWING FOR LARGER FLAKES TO BE MIXED IN OR EVEN BE
DOMINANT...ALLOWING FOR QUICKER RATES AND SOME HIGHER
ACCUMULATIONS. WHILE PAVEMENT ACCUMULATION WILL BE MUCH LESS WITH
STILL ONLY SOME LIGHT SLUSH ANTICIPATED /AND HARDLY ANY REPORTED
YET/...THE TIMING CONTINUES TO IMPACT THE COMMUTE WITH LOW
VISIBILITY...SO WE CONTINUE THAT MESSAGE WITHIN OUR FORECAST.
MTF
&&
.SHORT TERM...
329 AM CST
THROUGH THURSDAY...
THE SECOND SNOW OF THE SEASON IS UNDERWAY THIS MORNING. WHILE MUCH
LESS IN TOTAL AMOUNT THAN THE NOVEMBER 20-21 EVENT...THE TIMING IS
PROBLEMATIC. HAVE REFINED HOURLY FORECASTS TO GIVE DETAIL OF
EXPECTED MODERATE/HEAVIER SNOWFALL TIMING AS OBSERVATIONAL TRENDS
SHOW THEIR HAND...THOUGH THIS IS STILL LARGELY IN AGREEMENT WITH
PREVIOUS FORECAST. HAVE INCREASED FORECAST SNOWFALL TOTALS ON
GRASS SURFACES INTO THE 1 TO 2 INCH CATEGORY FOR MANY WITH
ISOLATED HIGHER AMOUNTS PROBABLE GIVEN THE SLOW MOVING NATURE OF
THE MODEST RATES. CONTINUE WITH MESSAGING IN THE SPS AND
GRAPHICAL NOWCASTS TOWARD HIGHEST IMPACTS THROUGH 10 AM AND THUS
IMPACTING COMMUTERS.
THE BROAD BUT STRONG UPPER LOW IS GYRATING OVER THE
WI/MN/IA/NORTHERN IL REGION THIS MORNING. A NOTEWORTHY EMBEDDED
VORTICITY CENTER IS LIFTING NORTHEASTWARD OVER NORTHERN MO THIS
MORNING WHICH WILL MOVE OVER NORTHEAST ILLINOIS AROUND DAYBREAK. ON
THE LEADING EDGE OF THIS IS A FAVORED AREA FOR FOCUSED MORE INTENSE
ASCENT WHICH WILL OVERRIDE THE ONGOING PRECIPITATION...MAINLY
SNOW...SPREADING EAST ACROSS NORTHERN ILLINOIS AS OF 315 AM. THIS
MORE INTENSE SYNOPTIC LIFT LOOKS TO COINCIDE WITH THE LOWER TO
MID-LEVEL TEMPERATURE GRADIENT WHICH IS TIGHTENING AND ADDING
RESPONSIVE MESOSCALE LIFT...ESPECIALLY WITH CONDITIONAL
INSTABILITY ABOVE THAT PER THE RAP MODEL. ALL THIS POINTS TOWARD
AN AREA/BAND OF SNOW TO INTENSIFY ACROSS NORTHEAST
ILLINOIS...INCLUDING MUCH OF THE CHICAGO METRO AREA THROUGH 730 AM
OR SO. HIGH-RESOLUTION MODELS GENERALLY SUPPORT THIS...SHIFTING
INTO NORTHWEST INDIANA BUT LIKELY WEAKENING SOME DURING THE 7 TO
10 AM TIME OR SO. SOME OF THIS PRECIPITATION IN NORTHWEST INDIANA
WILL LIKELY BE RAIN OR A MIX AT ONSET...BUT SHOULD SHIFT QUICKLY
TO SNOW AS DIABATIC COOLING OCCURS.
WEBCAM IMAGERY AND A FEW EARLY MORNING REPORTS ARE INDICATING QUICK
ACCUMULATIONS IN EXCESS OF AN INCH ON GRASS. WHILE PAVEMENT HAS BEEN
RELATIVELY FREE OF SNOW ACCUMULATION THUS FAR...THE HEAVIER RATES
WILL COMPENSATE FOR THAT WITH LIKELY SOME LIGHT SLUSHY
ACCUMULATION IN PLACES. THIS MAY BE A LITTLE HARDER TO COME BY IN
DOWNTOWN CHICAGO WHERE OBSERVATIONS STILL INDICATE AIR
TEMPERATURES OF 37-38 DEGREES AS OF 315 AM.
BEHIND THIS SNOW AREA...SNOW SHOWERS UNDER THE COLD POCKET ALOFT
AND OTHER EMBEDDED BUT WEAKER VORTICITY MAXIMAS WILL MOVE EASTWARD
INTO NORTH CENTRAL ILLINOIS THIS MORNING AND ACROSS THE REST OF
THE AREA. COVERAGE OF THESE SNOW SHOWERS IS LIKELY TO UNDULATE
SOME...BUT HAVE BASICALLY KEPT HIGH PROBABILITIES FOR SNOW THROUGH
EARLY AFTERNOON ACROSS NORTH CENTRAL ILLINOIS AND MUCH OF THE DAY
FOR EASTWARD...THOUGH THE DEFINITE POPS AND HEAVIER WORDING IS IN
THE EARLY MORNING.
TEMPERATURES WILL LIKELY TRY TO REBOUND A FEW DEGREES LATE THIS
MORNING AND AFTERNOON...WHICH MAY MELT SOME OF THE SNOW THAT
FALLS. THE TEMPERATURE FORECAST FOR TONIGHT IS CHALLENGING AS
THERE ARE LIKELY TO BE HOLES IN THE CLOUD COVER YET THE CYCLONIC
FLOW WILL INEVITABLY KEEP SOME LARGE AREAS OF CLOUDS TOO. FOR
THOSE LOCATIONS THAT CLEAR...MID 20S LOOK LIKE A GOOD BET.
LINGERING CLOUDS THURSDAY MORNING SHOULD ABATE BY THURSDAY
AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
THURSDAY NIGHT THROUGH TUESDAY...
THE PATTERN FOR LATE IN THE WEEK THROUGH EARLY NEXT WEEK CONTINUES
TO LOOK MAINLY DRY AND MILD...WITH HIGHEST CONFIDENCE IN THE
MILD AIR ON SATURDAY WHERE HIGHS COULD REACH LOWER TO MID 50S
AREAWIDE. WHILE NO GUIDANCE HAS THIS IN THEIR SURFACE TEMPERATURE
PREDICTIONS...CLIMATOLOGY WOULD SUPPORT SUCH READINGS GIVEN THEIR
FORECAST 925MB TEMPERATURES AND DEGREE OF ANOMALIES.
THE 00Z GFS AND EC BOTH INDICATE A WEAK BOUNDARY SINKING SOUTHWARD
NEAR OR INTO THE AREA ON SUNDAY...ALONG WITH ANOTHER SLOW-MOVING BUT
MUCH WEAKER/SMALLER UPPER LOW TO THE NEARBY SOUTHWEST. TOGETHER
THIS COULD BRING SOME CLOUDS AND KEEP TEMPERATURES A LITTLE COOLER
THAN SATURDAY AND HAVE FAVORED THAT ROUTE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SNOW SHOWERS THROUGH MID AFTERNOON WITH IFR TO LIFR VIS LIKELY
AT TIMES.
* LOW MVFR TO IFR CIGS INTO EARLY AFTERNOON.
* NW WIND GUSTS TO 20 KT LATE THIS AFTERNOON/EARLY EVENING.
KMD/KB
//DISCUSSION...UPDATED 12Z...
SNOWFALL RATES HAVE PICKED UP CONSIDERABLY IN RESPONSE TO THE MID LEVEL
WAVE LIFTING NORTHEAST AND INTERACTING WITH A STRENGTHENING LOW
LEVEL FRONTAL ZONE. HAVE SEEN VERY INFREQUENT 3/4SM VSBYS IN THE
HEAVIEST RATES AT BOTH KPWK AND KUGN AND NOW AT KPA...BUT MOST
AREAS HAVE NOT GOTTEN LOWER THAN 1SM. CIGS ARE A MIX OF LOW MVFR
WHERE SNOW HAS NOT BEEN FALLING AS LONG TO LIFR FARTHER WEST.
SHORT TERM GUIDANCE IS IN GOOD AGREEMENT THAT THE MAX INTENSITY IS
OCCURRING NOW AND THROUGH ABOUT 14Z. WILL HOLD THE TEMPO 3/4SM AT
ORD AND 1SM AT KMDW. VSBYS COULD BE BRIEFLY LOWER THAN THOSE
INDICATED IN THE TAF WITH 1 MINUTE DATA AT KORD JUST RECENTLY
COMING IN WITH THE FIRST OBSERVATION OF 1/2SM. ACCUMS ON PAVEMENT
SHOULD BE LIMITED TO MAYBE SOME LIGHT SLUSHY ACCUMS.
AFTER THIS SNOW BAND MOVES INTO NW INDIANA...EXPECT CIGS TO LIFT TO
MVFR OR POSSIBLY BRIEFLY IFR AND VSBYS TO IMPROVE AS WELL. THERE
IS A CONCENTRATED AREA OF SNOW SHOWERS LAGGING BEHIND THIS SNOW
BAND BY A FEW HOURS. UPSTREAM OBS SUGGEST MVFR AND EVEN IFR VSBY
IN THESE SHOWERS...THOUGH THEY MAY GET LESS ORGANIZED AS THEY
SHIFT SE. CIGS LIKELY SETTLE BACK TO MVFR. WILL HANDLE THIS WITH A
TEMPO FOR THE LATER MORNING HOURS WITH AHEAD OF A WEAK SURFACE
TROUGH.
WINDS SHOULD LARGELY BE SW SHIFTING TO W AND THEN NW THROUGH THE DAY.
NO SIGNIFICANT GUSTS ARE EXPECTED THOUGH WE MAY TAP SOME MID
TEENS GUSTS IN THE LATER AFTERNOON AND EVENING AS WINDS SHIFT TO
NW AND WINDS ALOFT INCREASE. WE KEEP A NW WIND THROUGH THE
NIGHT...WITH GUIDANCE MIXED AS TO WHETHER CIGS ARE SCT OR BROKEN.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM-HIGH IN OCCASIONAL IFR VSBY IN SNOW SHOWERS TODAY.
* MEDIUM-HIGH IN LOW MVFR TO IFR CIGS INTO EARLY AFTERNOON.
* MEDIUM ON WIND GUSTS THIS AFTERNOON/EVENING.
KMD/KB
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
FRIDAY THROUGH TUESDAY...VFR WITH GENERALLY SW WINDS. WINDS MAY
SHIFT TO VARIABLE/EASTERLY ON MONDAY.
KMD
&&
.MARINE...
108 AM CST
A LOW PRESSURE TROUGH EXTENDS FROM THE LOW CENTER ACROSS LAKE
SUPERIOR SOUTHWESTWARD TO THE UPPER MISSISSIPPI VALLEY. THE TROUGH
AXIS WILL CROSS LAKE MICHIGAN THIS MORNING...WITH A COLD FRONT
SPREADING ACROSS THE LAKE THROUGH THE DAY. WINDS QUICKLY SHIFT TO
NORTHWESTERLY BEHIND THE FRONT AND INCREASE THIS
AFTERNOON...ESPECIALLY OVER THE SOUTH HALF. WITH THE DEVELOPMENT
OF A SECONDARY LOW CENTER OVER THE LAKE...MODEST PRESSURE RISES AS
THE LOW DEPARTS COULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS OVER
THE INDIANA NEARSHORE WATERS. HIGH PRESSURE WILL MOVE INTO THE
OHIO VALLEY LATER THURSDAY INTO FRIDAY WITH THE RIDGE AXIS MOVING
OVER THE LAKE FRIDAY. THE HIGH STRENGTHENS OVER THE EASTERN U.S.
WHILE LOW PRESSURE SKIRTS EAST THROUGH HUDSON BAY LATER IN THE
WEEKEND. THE HIGH WILL EXPAND OVER THE LAKE ON MONDAY. THIS
PATTERN SUGGESTS AN EXTENDED PERIOD OF LIGHTER TO MODEST SOUTH-
SOUTHWEST WINDS AND RELATIVELY BENIGN CONDITIONS FOR DECEMBER
AFTER TODAYS COLD FRONT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
806 AM CST WED DEC 2 2015
.MESOSCALE DISCUSSION...
600 AM CST
SNOW OVER NORTHEAST ILLINOIS HAS INTENSIFIED PRETTY MUCH AS
ANTICIPATED. SOME TEMPORARY ONE HALF MILE VISIBILITY HAS BEEN
REPORTED AND CONTINUE TO EXPECT THAT ACROSS THE CHICAGO METRO AT
TIMES THROUGH 730 AM. SNOWFALL IS ACCUMULATING READILY ON GRASSY
SURFACES WITH STILL NOT MUCH HAVING BEEN REPORTED ON PAVED
SURFACES...INCLUDING UP NEAR WOODSTOCK WHERE AN ISOLATED TOTAL OF
3.5 INCHES WAS REPORTED FROM ONE OF OUR OBSERVERS.
THESE ISOLATED HIGHER TOTALS IN EXCESS OF TWO INCHES WILL REMAIN
POSSIBLE NOT ONLY AIDED BY HEAVIER RATES BUT ALSO LARGER
SNOWFLAKES. A RECENT AIRCRAFT SOUNDING FROM ORD INDICATED WIND
SPEEDS LIGHTER THAN 10 KT ALL THE WAY UP TO 3500 FT INDICATING
LITTLE IN THE WAY OF FRAGMENTING ALLOWING FOR LARGER FLAKES TO
REACH THE GROUND...WHICH WE OBSERVED HERE AT THE WFO FOR A PERIOD.
THE SOUNDING ALSO INDICATED A PRONOUNCED ISOTHERMAL PROFILE NEAR
-5C...LIKELY RIGHT WITHIN THE FRONTOGENETIC LAYER...AND THIS IS
ALL UNDERNEATH A SATURATED DENDRITIC GROWTH AREA. ALTOGETHER THIS
IS ALLOWING FOR LARGER FLAKES TO BE MIXED IN OR EVEN BE
DOMINANT...ALLOWING FOR QUICKER RATES AND SOME HIGHER
ACCUMULATIONS. WHILE PAVEMENT ACCUMULATION WILL BE MUCH LESS WITH
STILL ONLY SOME LIGHT SLUSH ANTICIPATED /AND HARDLY ANY REPORTED
YET/...THE TIMING CONTINUES TO IMPACT THE COMMUTE WITH LOW
VISIBILITY...SO WE CONTINUE THAT MESSAGE WITHIN OUR FORECAST.
MTF
&&
.SHORT TERM...
329 AM CST
THROUGH THURSDAY...
THE SECOND SNOW OF THE SEASON IS UNDERWAY THIS MORNING. WHILE MUCH
LESS IN TOTAL AMOUNT THAN THE NOVEMBER 20-21 EVENT...THE TIMING IS
PROBLEMATIC. HAVE REFINED HOURLY FORECASTS TO GIVE DETAIL OF
EXPECTED MODERATE/HEAVIER SNOWFALL TIMING AS OBSERVATIONAL TRENDS
SHOW THEIR HAND...THOUGH THIS IS STILL LARGELY IN AGREEMENT WITH
PREVIOUS FORECAST. HAVE INCREASED FORECAST SNOWFALL TOTALS ON
GRASS SURFACES INTO THE 1 TO 2 INCH CATEGORY FOR MANY WITH
ISOLATED HIGHER AMOUNTS PROBABLE GIVEN THE SLOW MOVING NATURE OF
THE MODEST RATES. CONTINUE WITH MESSAGING IN THE SPS AND
GRAPHICAL NOWCASTS TOWARD HIGHEST IMPACTS THROUGH 10 AM AND THUS
IMPACTING COMMUTERS.
THE BROAD BUT STRONG UPPER LOW IS GYRATING OVER THE
WI/MN/IA/NORTHERN IL REGION THIS MORNING. A NOTEWORTHY EMBEDDED
VORTICITY CENTER IS LIFTING NORTHEASTWARD OVER NORTHERN MO THIS
MORNING WHICH WILL MOVE OVER NORTHEAST ILLINOIS AROUND DAYBREAK. ON
THE LEADING EDGE OF THIS IS A FAVORED AREA FOR FOCUSED MORE INTENSE
ASCENT WHICH WILL OVERRIDE THE ONGOING PRECIPITATION...MAINLY
SNOW...SPREADING EAST ACROSS NORTHERN ILLINOIS AS OF 315 AM. THIS
MORE INTENSE SYNOPTIC LIFT LOOKS TO COINCIDE WITH THE LOWER TO
MID-LEVEL TEMPERATURE GRADIENT WHICH IS TIGHTENING AND ADDING
RESPONSIVE MESOSCALE LIFT...ESPECIALLY WITH CONDITIONAL
INSTABILITY ABOVE THAT PER THE RAP MODEL. ALL THIS POINTS TOWARD
AN AREA/BAND OF SNOW TO INTENSIFY ACROSS NORTHEAST
ILLINOIS...INCLUDING MUCH OF THE CHICAGO METRO AREA THROUGH 730 AM
OR SO. HIGH-RESOLUTION MODELS GENERALLY SUPPORT THIS...SHIFTING
INTO NORTHWEST INDIANA BUT LIKELY WEAKENING SOME DURING THE 7 TO
10 AM TIME OR SO. SOME OF THIS PRECIPITATION IN NORTHWEST INDIANA
WILL LIKELY BE RAIN OR A MIX AT ONSET...BUT SHOULD SHIFT QUICKLY
TO SNOW AS DIABATIC COOLING OCCURS.
WEBCAM IMAGERY AND A FEW EARLY MORNING REPORTS ARE INDICATING QUICK
ACCUMULATIONS IN EXCESS OF AN INCH ON GRASS. WHILE PAVEMENT HAS BEEN
RELATIVELY FREE OF SNOW ACCUMULATION THUS FAR...THE HEAVIER RATES
WILL COMPENSATE FOR THAT WITH LIKELY SOME LIGHT SLUSHY
ACCUMULATION IN PLACES. THIS MAY BE A LITTLE HARDER TO COME BY IN
DOWNTOWN CHICAGO WHERE OBSERVATIONS STILL INDICATE AIR
TEMPERATURES OF 37-38 DEGREES AS OF 315 AM.
BEHIND THIS SNOW AREA...SNOW SHOWERS UNDER THE COLD POCKET ALOFT
AND OTHER EMBEDDED BUT WEAKER VORTICITY MAXIMAS WILL MOVE EASTWARD
INTO NORTH CENTRAL ILLINOIS THIS MORNING AND ACROSS THE REST OF
THE AREA. COVERAGE OF THESE SNOW SHOWERS IS LIKELY TO UNDULATE
SOME...BUT HAVE BASICALLY KEPT HIGH PROBABILITIES FOR SNOW THROUGH
EARLY AFTERNOON ACROSS NORTH CENTRAL ILLINOIS AND MUCH OF THE DAY
FOR EASTWARD...THOUGH THE DEFINITE POPS AND HEAVIER WORDING IS IN
THE EARLY MORNING.
TEMPERATURES WILL LIKELY TRY TO REBOUND A FEW DEGREES LATE THIS
MORNING AND AFTERNOON...WHICH MAY MELT SOME OF THE SNOW THAT
FALLS. THE TEMPERATURE FORECAST FOR TONIGHT IS CHALLENGING AS
THERE ARE LIKELY TO BE HOLES IN THE CLOUD COVER YET THE CYCLONIC
FLOW WILL INEVITABLY KEEP SOME LARGE AREAS OF CLOUDS TOO. FOR
THOSE LOCATIONS THAT CLEAR...MID 20S LOOK LIKE A GOOD BET.
LINGERING CLOUDS THURSDAY MORNING SHOULD ABATE BY THURSDAY
AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
THURSDAY NIGHT THROUGH TUESDAY...
THE PATTERN FOR LATE IN THE WEEK THROUGH EARLY NEXT WEEK CONTINUES
TO LOOK MAINLY DRY AND MILD...WITH HIGHEST CONFIDENCE IN THE
MILD AIR ON SATURDAY WHERE HIGHS COULD REACH LOWER TO MID 50S
AREAWIDE. WHILE NO GUIDANCE HAS THIS IN THEIR SURFACE TEMPERATURE
PREDICTIONS...CLIMATOLOGY WOULD SUPPORT SUCH READINGS GIVEN THEIR
FORECAST 925MB TEMPERATURES AND DEGREE OF ANOMALIES.
THE 00Z GFS AND EC BOTH INDICATE A WEAK BOUNDARY SINKING SOUTHWARD
NEAR OR INTO THE AREA ON SUNDAY...ALONG WITH ANOTHER SLOW-MOVING BUT
MUCH WEAKER/SMALLER UPPER LOW TO THE NEARBY SOUTHWEST. TOGETHER
THIS COULD BRING SOME CLOUDS AND KEEP TEMPERATURES A LITTLE COOLER
THAN SATURDAY AND HAVE FAVORED THAT ROUTE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* LOW MVFR/IFR CIGS BRIEFLY TAGGING LIFR IN HEAVIER SNOW...IMPROVING
TO MVFR BY LATE MORNING.
* SNOW WITH IFR TO LIFR VIS LIKELY THROUGH 15Z. VSBYS AS LOW AS
1/2SM OCCASIONALLY. GRADUAL IMPROVEMENT AFTER 15 UTC.
* OCCASIONAL SNOW SHOWERS TODAY WITH REDUCTIONS IN VSBY TO TO IFR.
* NW WIND GUSTS TO 20 KT LATE THIS AFTERNOON/EARLY EVENING.
KMD/KB
//DISCUSSION...UPDATED 12Z...
SNOWFALL RATES HAVE PICKED UP CONSIDERABLY IN RESPONSE TO THE MID LEVEL
WAVE LIFTING NORTHEAST AND INTERACTING WITH A STRENGTHENING LOW
LEVEL FRONTAL ZONE. HAVE SEEN VERY INFREQUENT 3/4SM VSBYS IN THE
HEAVIEST RATES AT BOTH KPWK AND KUGN AND NOW AT KPA...BUT MOST
AREAS HAVE NOT GOTTEN LOWER THAN 1SM. CIGS ARE A MIX OF LOW MVFR
WHERE SNOW HAS NOT BEEN FALLING AS LONG TO LIFR FARTHER WEST.
SHORT TERM GUIDANCE IS IN GOOD AGREEMENT THAT THE MAX INTENSITY IS
OCCURRING NOW AND THROUGH ABOUT 14Z. WILL HOLD THE TEMPO 3/4SM AT
ORD AND 1SM AT KMDW. VSBYS COULD BE BRIEFLY LOWER THAN THOSE
INDICATED IN THE TAF WITH 1 MINUTE DATA AT KORD JUST RECENTLY
COMING IN WITH THE FIRST OBSERVATION OF 1/2SM. ACCUMS ON PAVEMENT
SHOULD BE LIMITED TO MAYBE SOME LIGHT SLUSHY ACCUMS.
AFTER THIS SNOW BAND MOVES INTO NW INDIANA...EXPECT CIGS TO LIFT TO
MVFR OR POSSIBLY BRIEFLY IFR AND VSBYS TO IMPROVE AS WELL. THERE
IS A CONCENTRATED AREA OF SNOW SHOWERS LAGGING BEHIND THIS SNOW
BAND BY A FEW HOURS. UPSTREAM OBS SUGGEST MVFR AND EVEN IFR VSBY
IN THESE SHOWERS...THOUGH THEY MAY GET LESS ORGANIZED AS THEY
SHIFT SE. CIGS LIKELY SETTLE BACK TO MVFR. WILL HANDLE THIS WITH A
TEMPO FOR THE LATER MORNING HOURS WITH AHEAD OF A WEAK SURFACE
TROUGH.
WINDS SHOULD LARGELY BE SW SHIFTING TO W AND THEN NW THROUGH THE DAY.
NO SIGNIFICANT GUSTS ARE EXPECTED THOUGH WE MAY TAP SOME MID
TEENS GUSTS IN THE LATER AFTERNOON AND EVENING AS WINDS SHIFT TO
NW AND WINDS ALOFT INCREASE. WE KEEP A NW WIND THROUGH THE
NIGHT...WITH GUIDANCE MIXED AS TO WHETHER CIGS ARE SCT OR BROKEN.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH IN SNOW TAPERING IN THE NEXT FEW HOURS.
* MEDIUM IN OCCASIONAL IFR VSBY IN SNOW SHOWERS TODAY.
* MEDIUM ON WIND GUSTS THIS AFTERNOON/EVENING.
KMD/KB
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
FRIDAY THROUGH TUESDAY...VFR WITH GENERALLY SW WINDS. WINDS MAY
SHIFT TO VARIABLE/EASTERLY ON MONDAY.
KMD
&&
.MARINE...
108 AM CST
A LOW PRESSURE TROUGH EXTENDS FROM THE LOW CENTER ACROSS LAKE
SUPERIOR SOUTHWESTWARD TO THE UPPER MISSISSIPPI VALLEY. THE TROUGH
AXIS WILL CROSS LAKE MICHIGAN THIS MORNING...WITH A COLD FRONT
SPREADING ACROSS THE LAKE THROUGH THE DAY. WINDS QUICKLY SHIFT TO
NORTHWESTERLY BEHIND THE FRONT AND INCREASE THIS
AFTERNOON...ESPECIALLY OVER THE SOUTH HALF. WITH THE DEVELOPMENT
OF A SECONDARY LOW CENTER OVER THE LAKE...MODEST PRESSURE RISES AS
THE LOW DEPARTS COULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS OVER
THE INDIANA NEARSHORE WATERS. HIGH PRESSURE WILL MOVE INTO THE
OHIO VALLEY LATER THURSDAY INTO FRIDAY WITH THE RIDGE AXIS MOVING
OVER THE LAKE FRIDAY. THE HIGH STRENGTHENS OVER THE EASTERN U.S.
WHILE LOW PRESSURE SKIRTS EAST THROUGH HUDSON BAY LATER IN THE
WEEKEND. THE HIGH WILL EXPAND OVER THE LAKE ON MONDAY. THIS
PATTERN SUGGESTS AN EXTENDED PERIOD OF LIGHTER TO MODEST SOUTH-
SOUTHWEST WINDS AND RELATIVELY BENIGN CONDITIONS FOR DECEMBER
AFTER TODAYS COLD FRONT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
605 AM CST WED DEC 2 2015
.MESOSCALE DISCUSSION...
600 AM CST
SNOW OVER NORTHEAST ILLINOIS HAS INTENSIFIED PRETTY MUCH AS
ANTICIPATED. SOME TEMPORARY ONE HALF MILE VISIBILITY HAS BEEN
REPORTED AND CONTINUE TO EXPECT THAT ACROSS THE CHICAGO METRO AT
TIMES THROUGH 730 AM. SNOWFALL IS ACCUMULATING READILY ON GRASSY
SURFACES WITH STILL NOT MUCH HAVING BEEN REPORTED ON PAVED
SURFACES...INCLUDING UP NEAR WOODSTOCK WHERE AN ISOLATED TOTAL OF
3.5 INCHES WAS REPORTED FROM ONE OF OUR OBSERVERS.
THESE ISOLATED HIGHER TOTALS IN EXCESS OF TWO INCHES WILL REMAIN
POSSIBLE NOT ONLY AIDED BY HEAVIER RATES BUT ALSO LARGER
SNOWFLAKES. A RECENT AIRCRAFT SOUNDING FROM ORD INDICATED WIND
SPEEDS LIGHTER THAN 10 KT ALL THE WAY UP TO 3500 FT INDICATING
LITTLE IN THE WAY OF FRAGMENTING ALLOWING FOR LARGER FLAKES TO
REACH THE GROUND...WHICH WE OBSERVED HERE AT THE WFO FOR A PERIOD.
THE SOUNDING ALSO INDICATED A PRONOUNCED ISOTHERMAL PROFILE NEAR
-5C...LIKELY RIGHT WITHIN THE FRONTOGENETIC LAYER...AND THIS IS
ALL UNDERNEATH A SATURATED DENDRITIC GROWTH AREA. ALTOGETHER THIS
IS ALLOWING FOR LARGER FLAKES TO BE MIXED IN OR EVEN BE
DOMINANT...ALLOWING FOR QUICKER RATES AND SOME HIGHER
ACCUMULATIONS. WHILE PAVEMENT ACCUMULATION WILL BE MUCH LESS WITH
STILL ONLY SOME LIGHT SLUSH ANTICIPATED /AND HARDLY ANY REPORTED
YET/...THE TIMING CONTINUES TO IMPACT THE COMMUTE WITH LOW
VISIBILITY...SO WE CONTINUE THAT MESSAGE WITHIN OUR FORECAST.
MTF
&&
.SHORT TERM...
329 AM CST
THROUGH THURSDAY...
THE SECOND SNOW OF THE SEASON IS UNDERWAY THIS MORNING. WHILE MUCH
LESS IN TOTAL AMOUNT THAN THE NOVEMBER 20-21 EVENT...THE TIMING IS
PROBLEMATIC. HAVE REFINED HOURLY FORECASTS TO GIVE DETAIL OF
EXPECTED MODERATE/HEAVIER SNOWFALL TIMING AS OBSERVATIONAL TRENDS
SHOW THEIR HAND...THOUGH THIS IS STILL LARGELY IN AGREEMENT WITH
PREVIOUS FORECAST. HAVE INCREASED FORECAST SNOWFALL TOTALS ON
GRASS SURFACES INTO THE 1 TO 2 INCH CATEGORY FOR MANY WITH
ISOLATED HIGHER AMOUNTS PROBABLE GIVEN THE SLOW MOVING NATURE OF
THE MODEST RATES. CONTINUE WITH MESSAGING IN THE SPS AND
GRAPHICAL NOWCASTS TOWARD HIGHEST IMPACTS THROUGH 10 AM AND THUS
IMPACTING COMMUTERS.
THE BROAD BUT STRONG UPPER LOW IS GYRATING OVER THE
WI/MN/IA/NORTHERN IL REGION THIS MORNING. A NOTEWORTHY EMBEDDED
VORTICITY CENTER IS LIFTING NORTHEASTWARD OVER NORTHERN MO THIS
MORNING WHICH WILL MOVE OVER NORTHEAST ILLINOIS AROUND DAYBREAK. ON
THE LEADING EDGE OF THIS IS A FAVORED AREA FOR FOCUSED MORE INTENSE
ASCENT WHICH WILL OVERRIDE THE ONGOING PRECIPITATION...MAINLY
SNOW...SPREADING EAST ACROSS NORTHERN ILLINOIS AS OF 315 AM. THIS
MORE INTENSE SYNOPTIC LIFT LOOKS TO COINCIDE WITH THE LOWER TO
MID-LEVEL TEMPERATURE GRADIENT WHICH IS TIGHTENING AND ADDING
RESPONSIVE MESOSCALE LIFT...ESPECIALLY WITH CONDITIONAL
INSTABILITY ABOVE THAT PER THE RAP MODEL. ALL THIS POINTS TOWARD
AN AREA/BAND OF SNOW TO INTENSIFY ACROSS NORTHEAST
ILLINOIS...INCLUDING MUCH OF THE CHICAGO METRO AREA THROUGH 730 AM
OR SO. HIGH-RESOLUTION MODELS GENERALLY SUPPORT THIS...SHIFTING
INTO NORTHWEST INDIANA BUT LIKELY WEAKENING SOME DURING THE 7 TO
10 AM TIME OR SO. SOME OF THIS PRECIPITATION IN NORTHWEST INDIANA
WILL LIKELY BE RAIN OR A MIX AT ONSET...BUT SHOULD SHIFT QUICKLY
TO SNOW AS DIABATIC COOLING OCCURS.
WEBCAM IMAGERY AND A FEW EARLY MORNING REPORTS ARE INDICATING QUICK
ACCUMULATIONS IN EXCESS OF AN INCH ON GRASS. WHILE PAVEMENT HAS BEEN
RELATIVELY FREE OF SNOW ACCUMULATION THUS FAR...THE HEAVIER RATES
WILL COMPENSATE FOR THAT WITH LIKELY SOME LIGHT SLUSHY
ACCUMULATION IN PLACES. THIS MAY BE A LITTLE HARDER TO COME BY IN
DOWNTOWN CHICAGO WHERE OBSERVATIONS STILL INDICATE AIR
TEMPERATURES OF 37-38 DEGREES AS OF 315 AM.
BEHIND THIS SNOW AREA...SNOW SHOWERS UNDER THE COLD POCKET ALOFT
AND OTHER EMBEDDED BUT WEAKER VORTICITY MAXIMAS WILL MOVE EASTWARD
INTO NORTH CENTRAL ILLINOIS THIS MORNING AND ACROSS THE REST OF
THE AREA. COVERAGE OF THESE SNOW SHOWERS IS LIKELY TO UNDULATE
SOME...BUT HAVE BASICALLY KEPT HIGH PROBABILITIES FOR SNOW THROUGH
EARLY AFTERNOON ACROSS NORTH CENTRAL ILLINOIS AND MUCH OF THE DAY
FOR EASTWARD...THOUGH THE DEFINITE POPS AND HEAVIER WORDING IS IN
THE EARLY MORNING.
TEMPERATURES WILL LIKELY TRY TO REBOUND A FEW DEGREES LATE THIS
MORNING AND AFTERNOON...WHICH MAY MELT SOME OF THE SNOW THAT
FALLS. THE TEMPERATURE FORECAST FOR TONIGHT IS CHALLENGING AS
THERE ARE LIKELY TO BE HOLES IN THE CLOUD COVER YET THE CYCLONIC
FLOW WILL INEVITABLY KEEP SOME LARGE AREAS OF CLOUDS TOO. FOR
THOSE LOCATIONS THAT CLEAR...MID 20S LOOK LIKE A GOOD BET.
LINGERING CLOUDS THURSDAY MORNING SHOULD ABATE BY THURSDAY
AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
THURSDAY NIGHT THROUGH TUESDAY...
THE PATTERN FOR LATE IN THE WEEK THROUGH EARLY NEXT WEEK CONTINUES
TO LOOK MAINLY DRY AND MILD...WITH HIGHEST CONFIDENCE IN THE
MILD AIR ON SATURDAY WHERE HIGHS COULD REACH LOWER TO MID 50S
AREAWIDE. WHILE NO GUIDANCE HAS THIS IN THEIR SURFACE TEMPERATURE
PREDICTIONS...CLIMATOLOGY WOULD SUPPORT SUCH READINGS GIVEN THEIR
FORECAST 925MB TEMPERATURES AND DEGREE OF ANOMALIES.
THE 00Z GFS AND EC BOTH INDICATE A WEAK BOUNDARY SINKING SOUTHWARD
NEAR OR INTO THE AREA ON SUNDAY...ALONG WITH ANOTHER SLOW-MOVING BUT
MUCH WEAKER/SMALLER UPPER LOW TO THE NEARBY SOUTHWEST. TOGETHER
THIS COULD BRING SOME CLOUDS AND KEEP TEMPERATURES A LITTLE COOLER
THAN SATURDAY AND HAVE FAVORED THAT ROUTE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* LOW MVFR/IFR CIGS BRIEFLY TAGGING LIFR IN HEAVIER SNOW...IMPROVING
TO MVFR BY LATE MORNING.
* SNOW WITH IFR CIGS/VIS LIKELY AND LIFR CONDITIONS POSSIBLE
BRIEFLY BEFORE 14Z. VSBYS AS LOW AS 1SM COMMMON...3/4SM
OCCASIONALLY. 1/2SM PSBL AS WELL.
* OCCASIONAL SNOW SHOWERS TODAY WITH REDUCTIONS IN VSBY TO
MVFR...POSSIBLY BRIEFLY IFR.
* NW WIND GUSTS TO 20 KT LATE THIS AFTERNOON/EARLY EVENING.
KMD
//DISCUSSION...UPDATED 12Z...
SNOWFALL RATES HAVE PICKED UP CONSIDERABLY IN RESPONSE TO THE MID LEVEL
WAVE LIFTING NORTHEAST AND INTERACTING WITH A STRENGTHENING LOW
LEVEL FRONTAL ZONE. HAVE SEEN VERY INFREQUENT 3/4SM VSBYS IN THE
HEAVIEST RATES AT BOTH KPWK AND KUGN AND NOW AT KPA...BUT MOST
AREAS HAVE NOT GOTTEN LOWER THAN 1SM. CIGS ARE A MIX OF LOW MVFR
WHERE SNOW HAS NOT BEEN FALLING AS LONG TO LIFR FARTHER WEST.
SHORT TERM GUIDANCE IS IN GOOD AGREEMENT THAT THE MAX INTENSITY IS
OCCURRING NOW AND THROUGH ABOUT 14Z. WILL HOLD THE TEMPO 3/4SM AT
ORD AND 1SM AT KMDW. VSBYS COULD BE BRIEFLY LOWER THAN THOSE
INDICATED IN THE TAF WITH 1 MINUTE DATA AT KORD JUST RECENTLY
COMING IN WITH THE FIRST OBSERVATION OF 1/2SM. ACCUMS ON PAVEMENT
SHOULD BE LIMITED TO MAYBE SOME LIGHT SLUSHY ACCUMS.
AFTER THIS SNOW BAND MOVES INTO NW INDIANA...EXPECT CIGS TO LIFT TO
MVFR OR POSSIBLY BRIEFLY IFR AND VSBYS TO IMPROVE AS WELL. THERE
IS A CONCENTRATED AREA OF SNOW SHOWERS LAGGING BEHIND THIS SNOW
BAND BY A FEW HOURS. UPSTREAM OBS SUGGEST MVFR AND EVEN IFR VSBY
IN THESE SHOWERS...THOUGH THEY MAY GET LESS ORGANIZED AS THEY
SHIFT SE. CIGS LIKELY SETTLE BACK TO MVFR. WILL HANDLE THIS WITH A
TEMPO FOR THE LATER MORNING HOURS WITH AHEAD OF A WEAK SURFACE
TROUGH.
WINDS SHOULD LARGELY BE SW SHIFTING TO W AND THEN NW THROUGH THE DAY.
NO SIGNFICANT GUSTS ARE EXPECTED THOUGH WE MAY TAP SOME MID TEENS
GUSTS IN THE LATER AFTERNOON AND EVENING AS WINDS SHIFT TO NW AND
WINDS ALOFT INCREASE. WE KEEP A NW WIND THROUGH THE NIGHT...WITH
GUIDANCE MIXED AS TO WHETHER CIGS ARE SCT OR BROKEN.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM IN GENERAL CIG TRENDS AND IN TIMING COINCIDENT WITH THE
SNOW BAND.
* HIGH IN SNOW TAPERING IN THE NEXT FEW HOURS. MEDIUM IN PREVAILING
CIG/VIS TRENDS WITH THE SNOW BAND...AND HIGH WITH AT LEAST AS LOW
AS 1SM VSBY IN THE SNOW BAND. LOW-MEDIUM ON DURATION OF 3/4SM
VSBY. MEDIUM IN EXACT TIMING/DURATION OF LOWEST CIG/VIS.
* MEDIUM IN OCCASIONAL MVFR/IFR VSBY IN SHOWERS TODAY.
* MEDIUM ON WIND GUSTS THIS AFTERNOON/EVENING.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
FRIDAY THROUGH TUESDAY...VFR WITH GENERALLY SW WINDS. WINDS MAY
SHIFT TO VARIABLE/EASTERLY ON MONDAY.
KMD
&&
.MARINE...
108 AM CST
A LOW PRESSURE TROUGH EXTENDS FROM THE LOW CENTER ACROSS LAKE
SUPERIOR SOUTHWESTWARD TO THE UPPER MISSISSIPPI VALLEY. THE TROUGH
AXIS WILL CROSS LAKE MICHIGAN THIS MORNING...WITH A COLD FRONT
SPREADING ACROSS THE LAKE THROUGH THE DAY. WINDS QUICKLY SHIFT TO
NORTHWESTERLY BEHIND THE FRONT AND INCREASE THIS
AFTERNOON...ESPECIALLY OVER THE SOUTH HALF. WITH THE DEVELOPMENT
OF A SECONDARY LOW CENTER OVER THE LAKE...MODEST PRESSURE RISES AS
THE LOW DEPARTS COULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS OVER
THE INDIANA NEARSHORE WATERS. HIGH PRESSURE WILL MOVE INTO THE
OHIO VALLEY LATER THURSDAY INTO FRIDAY WITH THE RIDGE AXIS MOVING
OVER THE LAKE FRIDAY. THE HIGH STRENGTHENS OVER THE EASTERN U.S.
WHILE LOW PRESSURE SKIRTS EAST THROUGH HUDSON BAY LATER IN THE
WEEKEND. THE HIGH WILL EXPAND OVER THE LAKE ON MONDAY. THIS
PATTERN SUGGESTS AN EXTENDED PERIOD OF LIGHTER TO MODEST SOUTH-
SOUTHWEST WINDS AND RELATIVELY BENIGN CONDITIONS FOR DECEMBER
AFTER TODAYS COLD FRONT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
549 AM CST WED DEC 2 2015
.SHORT TERM...
329 AM CST
THROUGH THURSDAY...
THE SECOND SNOW OF THE SEASON IS UNDERWAY THIS MORNING. WHILE MUCH
LESS IN TOTAL AMOUNT THAN THE NOVEMBER 20-21 EVENT...THE TIMING IS
PROBLEMATIC. HAVE REFINED HOURLY FORECASTS TO GIVE DETAIL OF
EXPECTED MODERATE/HEAVIER SNOWFALL TIMING AS OBSERVATIONAL TRENDS
SHOW THEIR HAND...THOUGH THIS IS STILL LARGELY IN AGREEMENT WITH
PREVIOUS FORECAST. HAVE INCREASED FORECAST SNOWFALL TOTALS ON
GRASS SURFACES INTO THE 1 TO 2 INCH CATEGORY FOR MANY WITH
ISOLATED HIGHER AMOUNTS PROBABLE GIVEN THE SLOW MOVING NATURE OF
THE MODEST RATES. CONTINUE WITH MESSAGING IN THE SPS AND
GRAPHICAL NOWCASTS TOWARD HIGHEST IMPACTS THROUGH 10 AM AND THUS
IMPACTING COMMUTERS.
THE BROAD BUT STRONG UPPER LOW IS GYRATING OVER THE
WI/MN/IA/NORTHERN IL REGION THIS MORNING. A NOTEWORTHY EMBEDDED
VORTICITY CENTER IS LIFTING NORTHEASTWARD OVER NORTHERN MO THIS
MORNING WHICH WILL MOVE OVER NORTHEAST ILLINOIS AROUND DAYBREAK. ON
THE LEADING EDGE OF THIS IS A FAVORED AREA FOR FOCUSED MORE INTENSE
ASCENT WHICH WILL OVERRIDE THE ONGOING PRECIPITATION...MAINLY
SNOW...SPREADING EAST ACROSS NORTHERN ILLINOIS AS OF 315 AM. THIS
MORE INTENSE SYNOPTIC LIFT LOOKS TO COINCIDE WITH THE LOWER TO
MID-LEVEL TEMPERATURE GRADIENT WHICH IS TIGHTENING AND ADDING
RESPONSIVE MESOSCALE LIFT...ESPECIALLY WITH CONDITIONAL
INSTABILITY ABOVE THAT PER THE RAP MODEL. ALL THIS POINTS TOWARD
AN AREA/BAND OF SNOW TO INTENSIFY ACROSS NORTHEAST
ILLINOIS...INCLUDING MUCH OF THE CHICAGO METRO AREA THROUGH 730 AM
OR SO. HIGH-RESOLUTION MODELS GENERALLY SUPPORT THIS...SHIFTING
INTO NORTHWEST INDIANA BUT LIKELY WEAKENING SOME DURING THE 7 TO
10 AM TIME OR SO. SOME OF THIS PRECIPITATION IN NORTHWEST INDIANA
WILL LIKELY BE RAIN OR A MIX AT ONSET...BUT SHOULD SHIFT QUICKLY
TO SNOW AS DIABATIC COOLING OCCURS.
WEBCAM IMAGERY AND A FEW EARLY MORNING REPORTS ARE INDICATING QUICK
ACCUMULATIONS IN EXCESS OF AN INCH ON GRASS. WHILE PAVEMENT HAS BEEN
RELATIVELY FREE OF SNOW ACCUMULATION THUS FAR...THE HEAVIER RATES
WILL COMPENSATE FOR THAT WITH LIKELY SOME LIGHT SLUSHY
ACCUMULATION IN PLACES. THIS MAY BE A LITTLE HARDER TO COME BY IN
DOWNTOWN CHICAGO WHERE OBSERVATIONS STILL INDICATE AIR
TEMPERATURES OF 37-38 DEGREES AS OF 315 AM.
BEHIND THIS SNOW AREA...SNOW SHOWERS UNDER THE COLD POCKET ALOFT
AND OTHER EMBEDDED BUT WEAKER VORTICITY MAXIMAS WILL MOVE EASTWARD
INTO NORTH CENTRAL ILLINOIS THIS MORNING AND ACROSS THE REST OF
THE AREA. COVERAGE OF THESE SNOW SHOWERS IS LIKELY TO UNDULATE
SOME...BUT HAVE BASICALLY KEPT HIGH PROBABILITIES FOR SNOW THROUGH
EARLY AFTERNOON ACROSS NORTH CENTRAL ILLINOIS AND MUCH OF THE DAY
FOR EASTWARD...THOUGH THE DEFINITE POPS AND HEAVIER WORDING IS IN
THE EARLY MORNING.
TEMPERATURES WILL LIKELY TRY TO REBOUND A FEW DEGREES LATE THIS
MORNING AND AFTERNOON...WHICH MAY MELT SOME OF THE SNOW THAT
FALLS. THE TEMPERATURE FORECAST FOR TONIGHT IS CHALLENGING AS
THERE ARE LIKELY TO BE HOLES IN THE CLOUD COVER YET THE CYCLONIC
FLOW WILL INEVITABLY KEEP SOME LARGE AREAS OF CLOUDS TOO. FOR
THOSE LOCATIONS THAT CLEAR...MID 20S LOOK LIKE A GOOD BET.
LINGERING CLOUDS THURSDAY MORNING SHOULD ABATE BY THURSDAY
AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
THURSDAY NIGHT THROUGH TUESDAY...
THE PATTERN FOR LATE IN THE WEEK THROUGH EARLY NEXT WEEK CONTINUES
TO LOOK MAINLY DRY AND MILD...WITH HIGHEST CONFIDENCE IN THE
MILD AIR ON SATURDAY WHERE HIGHS COULD REACH LOWER TO MID 50S
AREAWIDE. WHILE NO GUIDANCE HAS THIS IN THEIR SURFACE TEMPERATURE
PREDICTIONS...CLIMATOLOGY WOULD SUPPORT SUCH READINGS GIVEN THEIR
FORECAST 925MB TEMPERATURES AND DEGREE OF ANOMALIES.
THE 00Z GFS AND EC BOTH INDICATE A WEAK BOUNDARY SINKING SOUTHWARD
NEAR OR INTO THE AREA ON SUNDAY...ALONG WITH ANOTHER SLOW-MOVING BUT
MUCH WEAKER/SMALLER UPPER LOW TO THE NEARBY SOUTHWEST. TOGETHER
THIS COULD BRING SOME CLOUDS AND KEEP TEMPERATURES A LITTLE COOLER
THAN SATURDAY AND HAVE FAVORED THAT ROUTE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* LOW MVFR/IFR CIGS BRIEFLY TAGGING LIFR IN HEAVIER SNOW...IMPROVING
TO MVFR BY LATE MORNING.
* SNOW WITH IFR CIGS/VIS LIKELY AND LIFR CONDITIONS POSSIBLE
BRIEFLY BEFORE 14Z. VSBYS AS LOW AS 1SM COMMMON...3/4SM
OCCASIONALLY. 1/2SM PSBL AS WELL.
* OCCASIONAL SNOW SHOWERS TODAY WITH REDUCTIONS IN VSBY TO
MVFR...POSSIBLY BRIEFLY IFR.
* NW WIND GUSTS TO 20 KT LATE THIS AFTERNOON/EARLY EVENING.
KMD
//DISCUSSION...UPDATED 12Z...
SNOWFALL RATES HAVE PICKED UP CONSIDERABLY IN RESPONSE TO THE MID LEVEL
WAVE LIFTING NORTHEAST AND INTERACTING WITH A STRENGTHENING LOW
LEVEL FRONTAL ZONE. HAVE SEEN VERY INFREQUENT 3/4SM VSBYS IN THE
HEAVIEST RATES AT BOTH KPWK AND KUGN AND NOW AT KPA...BUT MOST
AREAS HAVE NOT GOTTEN LOWER THAN 1SM. CIGS ARE A MIX OF LOW MVFR
WHERE SNOW HAS NOT BEEN FALLING AS LONG TO LIFR FARTHER WEST.
SHORT TERM GUIDANCE IS IN GOOD AGREEMENT THAT THE MAX INTENSITY IS
OCCURRING NOW AND THROUGH ABOUT 14Z. WILL HOLD THE TEMPO 3/4SM AT
ORD AND 1SM AT KMDW. VSBYS COULD BE BRIEFLY LOWER THAN THOSE
INDICATED IN THE TAF WITH 1 MINUTE DATA AT KORD JUST RECENTLY
COMING IN WITH THE FIRST OBSERVATION OF 1/2SM. ACCUMS ON PAVEMENT
SHOULD BE LIMITED TO MAYBE SOME LIGHT SLUSHY ACCUMS.
AFTER THIS SNOW BAND MOVES INTO NW INDIANA...EXPECT CIGS TO LIFT TO
MVFR OR POSSIBLY BRIEFLY IFR AND VSBYS TO IMPROVE AS WELL. THERE
IS A CONCENTRATED AREA OF SNOW SHOWERS LAGGING BEHIND THIS SNOW
BAND BY A FEW HOURS. UPSTREAM OBS SUGGEST MVFR AND EVEN IFR VSBY
IN THESE SHOWERS...THOUGH THEY MAY GET LESS ORGANIZED AS THEY
SHIFT SE. CIGS LIKELY SETTLE BACK TO MVFR. WILL HANDLE THIS WITH A
TEMPO FOR THE LATER MORNING HOURS WITH AHEAD OF A WEAK SURFACE
TROUGH.
WINDS SHOULD LARGELY BE SW SHIFTING TO W AND THEN NW THROUGH THE DAY.
NO SIGNFICANT GUSTS ARE EXPECTED THOUGH WE MAY TAP SOME MID TEENS
GUSTS IN THE LATER AFTERNOON AND EVENING AS WINDS SHIFT TO NW AND
WINDS ALOFT INCREASE. WE KEEP A NW WIND THROUGH THE NIGHT...WITH
GUIDANCE MIXED AS TO WHETHER CIGS ARE SCT OR BROKEN.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM IN GENERAL CIG TRENDS AND IN TIMING COINCIDENT WITH THE
SNOW BAND.
* HIGH IN SNOW TAPERING IN THE NEXT FEW HOURS. MEDIUM IN PREVAILING
CIG/VIS TRENDS WITH THE SNOW BAND...AND HIGH WITH AT LEAST AS LOW
AS 1SM VSBY IN THE SNOW BAND. LOW-MEDIUM ON DURATION OF 3/4SM
VSBY. MEDIUM IN EXACT TIMING/DURATION OF LOWEST CIG/VIS.
* MEDIUM IN OCCASIONAL MVFR/IFR VSBY IN SHOWERS TODAY.
* MEDIUM ON WIND GUSTS THIS AFTERNOON/EVENING.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
FRIDAY THROUGH TUESDAY...VFR WITH GENERALLY SW WINDS. WINDS MAY
SHIFT TO VARIABLE/EASTERLY ON MONDAY.
KMD
&&
.MARINE...
108 AM CST
A LOW PRESSURE TROUGH EXTENDS FROM THE LOW CENTER ACROSS LAKE
SUPERIOR SOUTHWESTWARD TO THE UPPER MISSISSIPPI VALLEY. THE TROUGH
AXIS WILL CROSS LAKE MICHIGAN THIS MORNING...WITH A COLD FRONT
SPREADING ACROSS THE LAKE THROUGH THE DAY. WINDS QUICKLY SHIFT TO
NORTHWESTERLY BEHIND THE FRONT AND INCREASE THIS
AFTERNOON...ESPECIALLY OVER THE SOUTH HALF. WITH THE DEVELOPMENT
OF A SECONDARY LOW CENTER OVER THE LAKE...MODEST PRESSURE RISES AS
THE LOW DEPARTS COULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS OVER
THE INDIANA NEARSHORE WATERS. HIGH PRESSURE WILL MOVE INTO THE
OHIO VALLEY LATER THURSDAY INTO FRIDAY WITH THE RIDGE AXIS MOVING
OVER THE LAKE FRIDAY. THE HIGH STRENGTHENS OVER THE EASTERN U.S.
WHILE LOW PRESSURE SKIRTS EAST THROUGH HUDSON BAY LATER IN THE
WEEKEND. THE HIGH WILL EXPAND OVER THE LAKE ON MONDAY. THIS
PATTERN SUGGESTS AN EXTENDED PERIOD OF LIGHTER TO MODEST SOUTH-
SOUTHWEST WINDS AND RELATIVELY BENIGN CONDITIONS FOR DECEMBER
AFTER TODAYS COLD FRONT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
532 AM CST WED DEC 2 2015
.SHORT TERM...
329 AM CST
THROUGH THURSDAY...
THE SECOND SNOW OF THE SEASON IS UNDERWAY THIS MORNING. WHILE MUCH
LESS IN TOTAL AMOUNT THAN THE NOVEMBER 20-21 EVENT...THE TIMING IS
PROBLEMATIC. HAVE REFINED HOURLY FORECASTS TO GIVE DETAIL OF
EXPECTED MODERATE/HEAVIER SNOWFALL TIMING AS OBSERVATIONAL TRENDS
SHOW THEIR HAND...THOUGH THIS IS STILL LARGELY IN AGREEMENT WITH
PREVIOUS FORECAST. HAVE INCREASED FORECAST SNOWFALL TOTALS ON
GRASS SURFACES INTO THE 1 TO 2 INCH CATEGORY FOR MANY WITH
ISOLATED HIGHER AMOUNTS PROBABLE GIVEN THE SLOW MOVING NATURE OF
THE MODEST RATES. CONTINUE WITH MESSAGING IN THE SPS AND
GRAPHICAL NOWCASTS TOWARD HIGHEST IMPACTS THROUGH 10 AM AND THUS
IMPACTING COMMUTERS.
THE BROAD BUT STRONG UPPER LOW IS GYRATING OVER THE
WI/MN/IA/NORTHERN IL REGION THIS MORNING. A NOTEWORTHY EMBEDDED
VORTICITY CENTER IS LIFTING NORTHEASTWARD OVER NORTHERN MO THIS
MORNING WHICH WILL MOVE OVER NORTHEAST ILLINOIS AROUND DAYBREAK. ON
THE LEADING EDGE OF THIS IS A FAVORED AREA FOR FOCUSED MORE INTENSE
ASCENT WHICH WILL OVERRIDE THE ONGOING PRECIPITATION...MAINLY
SNOW...SPREADING EAST ACROSS NORTHERN ILLINOIS AS OF 315 AM. THIS
MORE INTENSE SYNOPTIC LIFT LOOKS TO COINCIDE WITH THE LOWER TO
MID-LEVEL TEMPERATURE GRADIENT WHICH IS TIGHTENING AND ADDING
RESPONSIVE MESOSCALE LIFT...ESPECIALLY WITH CONDITIONAL
INSTABILITY ABOVE THAT PER THE RAP MODEL. ALL THIS POINTS TOWARD
AN AREA/BAND OF SNOW TO INTENSIFY ACROSS NORTHEAST
ILLINOIS...INCLUDING MUCH OF THE CHICAGO METRO AREA THROUGH 730 AM
OR SO. HIGH-RESOLUTION MODELS GENERALLY SUPPORT THIS...SHIFTING
INTO NORTHWEST INDIANA BUT LIKELY WEAKENING SOME DURING THE 7 TO
10 AM TIME OR SO. SOME OF THIS PRECIPITATION IN NORTHWEST INDIANA
WILL LIKELY BE RAIN OR A MIX AT ONSET...BUT SHOULD SHIFT QUICKLY
TO SNOW AS DIABATIC COOLING OCCURS.
WEBCAM IMAGERY AND A FEW EARLY MORNING REPORTS ARE INDICATING QUICK
ACCUMULATIONS IN EXCESS OF AN INCH ON GRASS. WHILE PAVEMENT HAS BEEN
RELATIVELY FREE OF SNOW ACCUMULATION THUS FAR...THE HEAVIER RATES
WILL COMPENSATE FOR THAT WITH LIKELY SOME LIGHT SLUSHY
ACCUMULATION IN PLACES. THIS MAY BE A LITTLE HARDER TO COME BY IN
DOWNTOWN CHICAGO WHERE OBSERVATIONS STILL INDICATE AIR
TEMPERATURES OF 37-38 DEGREES AS OF 315 AM.
BEHIND THIS SNOW AREA...SNOW SHOWERS UNDER THE COLD POCKET ALOFT
AND OTHER EMBEDDED BUT WEAKER VORTICITY MAXIMAS WILL MOVE EASTWARD
INTO NORTH CENTRAL ILLINOIS THIS MORNING AND ACROSS THE REST OF
THE AREA. COVERAGE OF THESE SNOW SHOWERS IS LIKELY TO UNDULATE
SOME...BUT HAVE BASICALLY KEPT HIGH PROBABILITIES FOR SNOW THROUGH
EARLY AFTERNOON ACROSS NORTH CENTRAL ILLINOIS AND MUCH OF THE DAY
FOR EASTWARD...THOUGH THE DEFINITE POPS AND HEAVIER WORDING IS IN
THE EARLY MORNING.
TEMPERATURES WILL LIKELY TRY TO REBOUND A FEW DEGREES LATE THIS
MORNING AND AFTERNOON...WHICH MAY MELT SOME OF THE SNOW THAT
FALLS. THE TEMPERATURE FORECAST FOR TONIGHT IS CHALLENGING AS
THERE ARE LIKELY TO BE HOLES IN THE CLOUD COVER YET THE CYCLONIC
FLOW WILL INEVITABLY KEEP SOME LARGE AREAS OF CLOUDS TOO. FOR
THOSE LOCATIONS THAT CLEAR...MID 20S LOOK LIKE A GOOD BET.
LINGERING CLOUDS THURSDAY MORNING SHOULD ABATE BY THURSDAY
AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
THURSDAY NIGHT THROUGH TUESDAY...
THE PATTERN FOR LATE IN THE WEEK THROUGH EARLY NEXT WEEK CONTINUES
TO LOOK MAINLY DRY AND MILD...WITH HIGHEST CONFIDENCE IN THE
MILD AIR ON SATURDAY WHERE HIGHS COULD REACH LOWER TO MID 50S
AREAWIDE. WHILE NO GUIDANCE HAS THIS IN THEIR SURFACE TEMPERATURE
PREDICTIONS...CLIMATOLOGY WOULD SUPPORT SUCH READINGS GIVEN THEIR
FORECAST 925MB TEMPERATURES AND DEGREE OF ANOMALIES.
THE 00Z GFS AND EC BOTH INDICATE A WEAK BOUNDARY SINKING SOUTHWARD
NEAR OR INTO THE AREA ON SUNDAY...ALONG WITH ANOTHER SLOW-MOVING BUT
MUCH WEAKER/SMALLER UPPER LOW TO THE NEARBY SOUTHWEST. TOGETHER
THIS COULD BRING SOME CLOUDS AND KEEP TEMPERATURES A LITTLE COOLER
THAN SATURDAY AND HAVE FAVORED THAT ROUTE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* LOW MVFR/IFR CIGS BRIEFLY TAGGING LIFR IN HEAVIER SNOW...IMPROVING
TO MVFR BY LATE MORNING.
* SNOW WITH IFR CIGS/VIS LIKELY AND LIFR CONDITIONS POSSIBLE BRIEFLY
BEFORE 14Z. VSBYS AS LOW AS 1SM COMMMON...3/4SM COULD HAPPEN BUT
LIKELY INFREQUENT.
* OCCASIONAL SNOW SHOWERS TODAY WITH REDUCTIONS IN VSBY TO
MVFR...POSSIBLY BRIEFLY IFR.
* NW WIND GUSTS TO 20 KT LATE THIS AFTERNOON/EARLY EVENING.
KMD
//DISCUSSION...UPDATED 12Z...
SNOWFALL RATES HAVE PICKED UP CONSIDERABLY IN RESPONSE TO THE MID LEVEL
WAVE LIFTING NORTHEAST AND INTERACTING WITH A STRENGTHENING LOW
LEVEL FRONTAL ZONE. HAVE SEEN VERY INFREQUENT 3/4SM VSBYS IN THE
HEAVIEST RATES AT BOTH KPWK AND KUGN AND NOW AT KPA...BUT MOST
AREAS HAVE NOT GOTTEN LOWER THAN 1SM. CIGS ARE A MIX OF LOW MVFR
WHERE SNOW HAS NOT BEEN FALLING AS LONG TO LIFR FARTHER WEST.
SHORT TERM GUIDANCE IS IN GOOD AGREEMENT THAT THE MAX INTENSITY IS
OCCURRING NOW AND THROUGH ABOUT 14Z. WILL HOLD THE TEMPO 3/4SM AT
ORD AND 1SM AT KMDW. ACCUMS ON PAVEMENT SHOULD BE LIMITED TO MAYBE
SOME LIGHT SLUSHY ACCUMS.
AFTER THIS SNOW BAND MOVES INTO NW INDIANA...EXPECT CIGS TO LIFT TO
MVFR OR POSSIBLY BRIEFLY IFR AND VSBYS TO IMPROVE AS WELL. THERE
IS A CONCENTRATED AREA OF SNOW SHOWERS LAGGING BEHIND THIS SNOW
BAND BY A FEW HOURS. UPSTREAM OBS SUGGEST MVFR AND EVEN IFR VSBY
IN THESE SHOWERS...THOUGH THEY MAY GET LESS ORGANIZED AS THEY
SHIFT SE. CIGS LIKELY SETTLE BACK TO MVFR. WILL HANDLE THIS WITH A
TEMPO FOR THE LATER MORNING HOURS WITH AHEAD OF A WEAK SURFACE
TROUGH.
WINDS SHOULD LARGELY BE SW SHIFTING TO W AND THEN NW THROUGH THE DAY.
NO SIGNFICANT GUSTS ARE EXPECTED THOUGH WE MAY TAP SOME MID TEENS
GUSTS IN THE LATER AFTERNOON AND EVENING AS WINDS SHIFT TO NW AND
WINDS ALOFT INCREASE. WE KEEP A NW WIND THROUGH THE NIGHT...WITH
GUIDANCE MIXED AS TO WHETHER CIGS ARE SCT OR BROKEN.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM IN GENERAL CIG TRENDS AND IN TIMING COINCIDENT WITH THE
SNOW BAND.
* HIGH IN SNOW TAPERING IN THE NEXT FEW HOURS. MEDIUM IN PREVAILING
CIG/VIS TRENDS WITH THE SNOW BAND...AND HIGH WITH AT LEAST AS LOW
AS 1SM VSBY IN THE SNOW BAND. LOW-MEDIUM ON DURATION OF 3/4SM
VSBY. MEDIUM IN EXACT TIMING/DURATION OF LOWEST CIG/VIS.
* MEDIUM IN OCCASIONAL MVFR/IFR VSBY IN SHOWERS TODAY.
* MEDIUM ON WIND GUSTS THIS AFTERNOON/EVENING.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
FRIDAY THROUGH TUESDAY...VFR WITH GENERALLY SW WINDS. WINDS MAY
SHIFT TO VARIABLE/EASTERLY ON MONDAY.
KMD
&&
.MARINE...
108 AM CST
A LOW PRESSURE TROUGH EXTENDS FROM THE LOW CENTER ACROSS LAKE
SUPERIOR SOUTHWESTWARD TO THE UPPER MISSISSIPPI VALLEY. THE TROUGH
AXIS WILL CROSS LAKE MICHIGAN THIS MORNING...WITH A COLD FRONT
SPREADING ACROSS THE LAKE THROUGH THE DAY. WINDS QUICKLY SHIFT TO
NORTHWESTERLY BEHIND THE FRONT AND INCREASE THIS
AFTERNOON...ESPECIALLY OVER THE SOUTH HALF. WITH THE DEVELOPMENT
OF A SECONDARY LOW CENTER OVER THE LAKE...MODEST PRESSURE RISES AS
THE LOW DEPARTS COULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS OVER
THE INDIANA NEARSHORE WATERS. HIGH PRESSURE WILL MOVE INTO THE
OHIO VALLEY LATER THURSDAY INTO FRIDAY WITH THE RIDGE AXIS MOVING
OVER THE LAKE FRIDAY. THE HIGH STRENGTHENS OVER THE EASTERN U.S.
WHILE LOW PRESSURE SKIRTS EAST THROUGH HUDSON BAY LATER IN THE
WEEKEND. THE HIGH WILL EXPAND OVER THE LAKE ON MONDAY. THIS
PATTERN SUGGESTS AN EXTENDED PERIOD OF LIGHTER TO MODEST SOUTH-
SOUTHWEST WINDS AND RELATIVELY BENIGN CONDITIONS FOR DECEMBER
AFTER TODAYS COLD FRONT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
332 AM CST WED DEC 2 2015
.SHORT TERM...
329 AM CST
THROUGH THURSDAY...
THE SECOND SNOW OF THE SEASON IS UNDERWAY THIS MORNING. WHILE MUCH
LESS IN TOTAL AMOUNT THAN THE NOVEMBER 20-21 EVENT...THE TIMING IS
PROBLEMATIC. HAVE REFINED HOURLY FORECASTS TO GIVE DETAIL OF
EXPECTED MODERATE/HEAVIER SNOWFALL TIMING AS OBSERVATIONAL TRENDS
SHOW THEIR HAND...THOUGH THIS IS STILL LARGELY IN AGREEMENT WITH
PREVIOUS FORECAST. HAVE INCREASED FORECAST SNOWFALL TOTALS ON
GRASS SURFACES INTO THE 1 TO 2 INCH CATEGORY FOR MANY WITH
ISOLATED HIGHER AMOUNTS PROBABLE GIVEN THE SLOW MOVING NATURE OF
THE MODEST RATES. CONTINUE WITH MESSAGING IN THE SPS AND
GRAPHICAL NOWCASTS TOWARD HIGHEST IMPACTS THROUGH 10 AM AND THUS
IMPACTING COMMUTERS.
THE BROAD BUT STRONG UPPER LOW IS GYRATING OVER THE
WI/MN/IA/NORTHERN IL REGION THIS MORNING. A NOTEWORTHY EMBEDDED
VORTICITY CENTER IS LIFTING NORTHEASTWARD OVER NORTHERN MO THIS
MORNING WHICH WILL MOVE OVER NORTHEAST ILLINOIS AROUND DAYBREAK. ON
THE LEADING EDGE OF THIS IS A FAVORED AREA FOR FOCUSED MORE INTENSE
ASCENT WHICH WILL OVERRIDE THE ONGOING PRECIPITATION...MAINLY
SNOW...SPREADING EAST ACROSS NORTHERN ILLINOIS AS OF 315 AM. THIS
MORE INTENSE SYNOPTIC LIFT LOOKS TO COINCIDE WITH THE LOWER TO
MID-LEVEL TEMPERATURE GRADIENT WHICH IS TIGHTENING AND ADDING
RESPONSIVE MESOSCALE LIFT...ESPECIALLY WITH CONDITIONAL
INSTABILITY ABOVE THAT PER THE RAP MODEL. ALL THIS POINTS TOWARD
AN AREA/BAND OF SNOW TO INTENSIFY ACROSS NORTHEAST
ILLINOIS...INCLUDING MUCH OF THE CHICAGO METRO AREA THROUGH 730 AM
OR SO. HIGH-RESOLUTION MODELS GENERALLY SUPPORT THIS...SHIFTING
INTO NORTHWEST INDIANA BUT LIKELY WEAKENING SOME DURING THE 7 TO
10 AM TIME OR SO. SOME OF THIS PRECIPITATION IN NORTHWEST INDIANA
WILL LIKELY BE RAIN OR A MIX AT ONSET...BUT SHOULD SHIFT QUICKLY
TO SNOW AS DIABATIC COOLING OCCURS.
WEBCAM IMAGERY AND A FEW EARLY MORNING REPORTS ARE INDICATING QUICK
ACCUMULATIONS IN EXCESS OF AN INCH ON GRASS. WHILE PAVEMENT HAS BEEN
RELATIVELY FREE OF SNOW ACCUMULATION THUS FAR...THE HEAVIER RATES
WILL COMPENSATE FOR THAT WITH LIKELY SOME LIGHT SLUSHY
ACCUMULATION IN PLACES. THIS MAY BE A LITTLE HARDER TO COME BY IN
DOWNTOWN CHICAGO WHERE OBSERVATIONS STILL INDICATE AIR
TEMPERATURES OF 37-38 DEGREES AS OF 315 AM.
BEHIND THIS SNOW AREA...SNOW SHOWERS UNDER THE COLD POCKET ALOFT
AND OTHER EMBEDDED BUT WEAKER VORTICITY MAXIMAS WILL MOVE EASTWARD
INTO NORTH CENTRAL ILLINOIS THIS MORNING AND ACROSS THE REST OF
THE AREA. COVERAGE OF THESE SNOW SHOWERS IS LIKELY TO UNDULATE
SOME...BUT HAVE BASICALLY KEPT HIGH PROBABILITIES FOR SNOW THROUGH
EARLY AFTERNOON ACROSS NORTH CENTRAL ILLINOIS AND MUCH OF THE DAY
FOR EASTWARD...THOUGH THE DEFINITE POPS AND HEAVIER WORDING IS IN
THE EARLY MORNING.
TEMPERATURES WILL LIKELY TRY TO REBOUND A FEW DEGREES LATE THIS
MORNING AND AFTERNOON...WHICH MAY MELT SOME OF THE SNOW THAT
FALLS. THE TEMPERATURE FORECAST FOR TONIGHT IS CHALLENGING AS
THERE ARE LIKELY TO BE HOLES IN THE CLOUD COVER YET THE CYCLONIC
FLOW WILL INEVITABLY KEEP SOME LARGE AREAS OF CLOUDS TOO. FOR
THOSE LOCATIONS THAT CLEAR...MID 20S LOOK LIKE A GOOD BET.
LINGERING CLOUDS THURSDAY MORNING SHOULD ABATE BY THURSDAY
AFTERNOON.
MTF
&&
.LONG TERM...
329 AM CST
THURSDAY NIGHT THROUGH TUESDAY...
THE PATTERN FOR LATE IN THE WEEK THROUGH EARLY NEXT WEEK CONTINUES
TO LOOK MAINLY DRY AND MILD...WITH HIGHEST CONFIDENCE IN THE
MILD AIR ON SATURDAY WHERE HIGHS COULD REACH LOWER TO MID 50S
AREAWIDE. WHILE NO GUIDANCE HAS THIS IN THEIR SURFACE TEMPERATURE
PREDICTIONS...CLIMATOLOGY WOULD SUPPORT SUCH READINGS GIVEN THEIR
FORECAST 925MB TEMPERATURES AND DEGREE OF ANOMALIES.
THE 00Z GFS AND EC BOTH INDICATE A WEAK BOUNDARY SINKING SOUTHWARD
NEAR OR INTO THE AREA ON SUNDAY...ALONG WITH ANOTHER SLOW-MOVING BUT
MUCH WEAKER/SMALLER UPPER LOW TO THE NEARBY SOUTHWEST. TOGETHER
THIS COULD BRING SOME CLOUDS AND KEEP TEMPERATURES A LITTLE COOLER
THAN SATURDAY AND HAVE FAVORED THAT ROUTE.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* CIGS LOWERING TO IFR...POSSIBLY LIFR IN HEAVIER SNOW BANDS. CIGS IMPROVING
MVFR BY LATE MORNING.
* SNOW WITH IFR CIGS/VIS LIKELY AND LIFR CONDITIONS POSSIBLE
WEDNESDAY MORNING. 3/4SM VSBY OR POSSIBLY LOWER REMAIN A CONCERN.
* OCCASIONAL SNOW SHOWERS TODAY.
KMD
//DISCUSSION...UPDATED 09Z...
SNOWFALL RATES HAVE BEEN FAIRLY CONSISTENT OVERNIGHT WEST OF THE
MAIN CHICAGO TERMINALS. MVFR CIGS GIVE WAY TO IFR CIGS IN THE
SNOW...AND EVEN LIFR CIGS IN AREAS WHERE SNOW HAS BEEN FALLING FOR
A LONGER TIME. IFR VISIBILITIES...WHILE NOT ALL THE TIME...HAVE
BEEN FAIRLY CONSISTENT IN THE MODERATE TO HEAVY SNOW BANDS...AND
GENERALLY AROUND 1 3/4SM TO 2SM...BUT OCCASIONALLY AS LOW AS 1SM.
WATER VAPOR SHOWS THE STRONG UPPER LEVEL WAVE ROTATING AROUND THE
BASE OF THE TROUGH WHICH HAS LED TO SOME REINTENSIFICATION IN
SNOWFALL AND CORRESPONDING MORE IMPRESSIVE SIGNATUES OF HEAVIER
PRECIP RATES THAT COULD LEAD TO VISBYS BELOW 1SM. HAVE HELD TO
3/4SM VSBY IN THE TEMPO FOR ORD/DPA AS THESE ARE THE AREAS THAT
STAND THE BEST CHANCE FOR THIS. MDW MAY HAVE A HARDER TIME WITH
INITIALLY WARMER TEMPERATURES...BUT INCREASED RATES SHOULD GET
THERE TOO BUT AFTER SUNRISE. HAVE HELD A 1SM IN THE TEMPO AS THAT
IS BEEN THE WORST REPORTED FROM ASOS/AWOS SITES...BUT THE
POTENTIAL IS STILL THERE FOR LOWER. DONT THINK THESE VERY LOW
VSBYS WILL HOLD FOR SUPER LONG AS THE BANDS ARE COMING IN WAVES.
PREVIOUS DISCUSSION FROM 06Z..
STARING TO SEE INDICATIONS THAT SNOWFALL WILL BEGIN TO
INTENSIFY...WITH KRFD OBSERVING A QUICK BURST OF SNOW AND QUICKLY
DROPPING FROM 9SM TO 1 1/4SM VSBY. WE STILL HAVE A FEW HOURS FOR
THE BAND TO PROGRESS EASTWARD. SEVERAL FACTORS ARE COMING TOGETHER
FOR A QUICK AND MODERATE TO HEAVY SNOW BAND FIRST OVER THE WESTERN
BURBS AROUND 8Z...THAN INTO ORD/MDW AFTER 9Z-10Z. THERE IS A
POTENT VORT MAX ROUNDING THE BASE OF THE MASSIVE UPPER TROUGH THAT
WILL SOON SHIFT NE AND APPROACH THE AREA. THERE IS ALSO A GOOD LOW
LEVEL FRONTAL ZONE THAT WILL STRENGTHEN IN THE COMING HOURS AS
WELL. HAVE SEE 1 1/4 - 1 1/2SM VSBY GENERALLY OBSERVED IN THE
MODERATE SNOW AND HAVE CARRIED THIS AS THE PREVAILING VSBY. WITH
THE EXPECTED INTENSIFICATION...BELIEVE 3/4SM VSBY SHOULD BE
EASILY ATTAINED AND TRIED TO HIT THAT IN THE MOST FAVORED TIME
FRAME. CERTAINLY IF THE INTENSIFICATION OCCURS LOWER VSBY IS
POSSIBLE...BUT WILL TRY TO ADD THOSE DETAILS AS THE BAND SHIFTS
WITH THE 9Z UPDATE.
THE BAND SHOULD BE PROGRESSIVE AFTER ABOUT A 3 HOUR WINDOW KEEPING
SOME IFR VSBYS AROUND THAN LIKELY A SHORT BREAK BEFORE ADDITIONAL
SNOW SHOWERS ROTATE THROUGH THE AREA TODAY. EXPECT CIGS TO LIFT TO
MVFR THIS MORNING AND LINGER THERE THIS AFTERNOON OR LIFT TO VFR
WITH TEMPO MVFR IN SHOWERS. ANY HEAVIER SHOWERS COULD PRODUCE
MVFR/IFR VSBY BUT SHOULD BE SHORT LIVED.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM IN GENERAL CIG TRENDS AND IN TIMING COINCIDENT WITH THE
SNOW BAND.
* HIGH IN SNOW THIS MORNING. MEDIUM IN PREVAILING CIG/VIS TRENDS
WITH THE SNOW BAND...AND HIGH WITH AT LEAST 1SM VSBY IN THE SNOW
BAND AND POSSIBLY LOWER. MEDIUM IN EXACT TIMING/DURATION OF
LOWEST CIG/VIS.
* HIGH IN SCATTERED SHOWERS AFTER THE SNOW BAND TODAY BUT LOW ON
TERMINAL IMPACTS.
KMD
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
THURSDAY THROUGH MONDAY...VFR. WX NIL.
KREIN
&&
.MARINE...
108 AM CST
A LOW PRESSURE TROUGH EXTENDS FROM THE LOW CENTER ACROSS LAKE
SUPERIOR SOUTHWESTWARD TO THE UPPER MISSISSIPPI VALLEY. THE TROUGH
AXIS WILL CROSS LAKE MICHIGAN THIS MORNING...WITH A COLD FRONT
SPREADING ACROSS THE LAKE THROUGH THE DAY. WINDS QUICKLY SHIFT TO
NORTHWESTERLY BEHIND THE FRONT AND INCREASE THIS
AFTERNOON...ESPECIALLY OVER THE SOUTH HALF. WITH THE DEVELOPMENT
OF A SECONDARY LOW CENTER OVER THE LAKE...MODEST PRESSURE RISES AS
THE LOW DEPARTS COULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS OVER
THE INDIANA NEARSHORE WATERS. HIGH PRESSURE WILL MOVE INTO THE
OHIO VALLEY LATER THURSDAY INTO FRIDAY WITH THE RIDGE AXIS MOVING
OVER THE LAKE FRIDAY. THE HIGH STRENGTHENS OVER THE EASTERN U.S.
WHILE LOW PRESSURE SKIRTS EAST THROUGH HUDSON BAY LATER IN THE
WEEKEND. THE HIGH WILL EXPAND OVER THE LAKE ON MONDAY. THIS
PATTERN SUGGESTS AN EXTENDED PERIOD OF LIGHTER TO MODEST SOUTH-
SOUTHWEST WINDS AND RELATIVELY BENIGN CONDITIONS FOR DECEMBER
AFTER TODAYS COLD FRONT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1012 PM EST THU DEC 3 2015
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 310 PM EST THU DEC 3 2015
DRY AND WARMER WEATHER WILL OCCUR THROUGH THE WEEKEND AS HIGH PRESSURE
OVER THE MIDDLE MISSISSIPPI VALLEY MOVES EAST ACROSS THE OHIO VALLEY
LATE TONIGHT AND FRIDAY AND TO SOUTHERN NEW ENGLAND OVER THE WEEKEND.
AN UPPER TROUGH WILL MOVE OUR WAY SUNDAY NIGHT AND MONDAY. BUT AT THE
MOMENT MODELS INDICATE MORE CLOUDS...BUT ONLY SLIGHT CHANCE OF SHOWERS
SOUTH AROUND SUNDAY NIGHT. SLIGHTLY WARMER AND DRY WEATHER WILL OCCUR
NEXT WEEK AS HIGH PRESSURE BUILDS ALONG THE ATLANTIC COAST.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 1012 PM EST THU DEC 3 2015
THERE WILL BE A SHARP GRADIENT BETWEEN TOTAL CLOUD COVER AND CLEAR
SKIES TONIGHT. HAVE ADJUSTED SKY GRIDS IN LINE WITH HRRR LOW LEVEL
MOISTURE PROGS. CLOUD HAS BEEN TRYING TO ERODE AT THE EDGES ALL
EVENING BUT VERY SLOW TO DO SO. ADJUSTED MIN TEMPS ACCORDINGLY AS
WELL...WITH COOLEST TEMPS LIKELY IN THE SOUTH UNDER CLEAR SKIES.
PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 310 PM EST THU DEC 3 2015
SATELLITE INDICATES A LARGE AREA OF STRATUS OVER NORTH AND CENTRAL
SECTIONS...WHILE MOSTLY SUNNY SKIES HAVE CONTINUED ACROSS OUR SOUTH.
THE STATUS HAS BEEN CLEARING OVER WESTERN ILLINOIS....WHILE IT HAS
INCREASED A LITTLE ACROSS INDIANA.
EXPECT SOME CLEARING ACROSS ILLINOIS NEXT SEVERAL HOURS. HOWEVER RUC AND
NAM MODEL INDICATES POSSIBLE REDEVELOPMENT OF STRATUS AND FOG OVER
NORTH AND CENTRAL SECTIONS LATER TONIGHT. FOR NOW WILL KEEP SOME STRATUS
OVER NORTH AND CENTRAL SECTIONS OVERNIGHT...WHICH WOULD MINIMIZE THE
THREAT OF FOG. EVEN IF CLOUDS CLEAR...MODELS INDICATE SOME LOW LEVEL
SHEAR WHICH WOULD FAVOR STRATUS OVER FOG. SO FOR NOW WILL LEAVE OUT MENTION
OF FOG AS PARAMETERS ARE VERY IFFY. OVERNIGHT LOWS WILL BE IN THE MIDDLE
TO UPPER 20S WHICH IS CLOSE TO A MOS BLEND.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
ISSUED AT 310 PM EST THU DEC 3 2015
DRY AND WARMER WEATHER WILL OCCUR THIS WEEKEND AS HIGH PRESSURE
MOVES ON TO THE EAST AND MODELS BUILD AN UPPER RIDGE OVER THE
EASTERN U.S. MODEL SOUNDINGS INDICATE MOSTLY CLEAR SKIES THROUGH
SATURDAY NIGHT AND THEN INCREASING CLOUDS SUNDAY AS AN UPPER TROUGH
MOVES OUR WAY.
MOST MODELS KEEP US DRY THROUGH SUNDAY AFTERNOON...WHILE THE EURO
INDICATES TRACE PRECIP AMOUNTS WEST AND SOUTH LATE SUNDAY. WILL GO
WITH CONSENSUS AND KEEP EVERYTHING DRY THROUGH SUNDAY. HIGHS WILL
BE IN THE UPPER 40S TO LOWER 50S FRIDAY AND SUNDAY AND IN THE LOWER
TO MIDDLE 50S SATURDAY. LOWS WILL BE IN THE UPPER 20S TO AROUND 30
FRIDAY NIGHT AND IN THE LOWER 30S SATURDAY NIGHT. WENT SLIGHTLY ABOVE
A MOS BLEND ON HIGHS WITH SOME SUN AND WARM ADVECTION. OTHERWISE...STAYED
CLOSE TO A MOS BLEND ON LOWS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 240 PM EST THU DEC 3 2015
ENSEMBLES BRING AN UPPER WAVE ACROSS THE AREA SUNDAY NIGHT AS A WEAK
SURFACE SYSTEM SLIDES EAST ACROSS THE TENNESSEE VALLEY. MOISTURE
WILL BE LIMITED...HOWEVER THE FORCING IS ENOUGH TO CONTINUE TO CARRY
WEAK CHANCES OF RAIN SHOWERS ACROSS THE SOUTHERN TIER.
WEAK RIDGING WILL PREVAIL THROUGHOUT MOST OF THE EXTENDED WITH DRY
CONDITIONS AND WARMER THAN NORMAL TEMPERATURES THROUGHOUT NEXT
WEEK.
&&
.AVIATION /DISCUSSION FOR THE 040300Z KIND TAF UPDATE/...
ISSUED AT 926 PM EST THU DEC 3 2015
NO SIGNIFICANT CHANGES MADE TO THE FORECAST AT THIS TIME. PREVIOUS
DISCUSSION FOLLOWS.
EXTENSIVE AREA OF MVFR CEILINGS 012-020 COVERS MOST OF NORTHERN AND
CENTRAL INDIANA...AFFECTING THE KLAF/KHUF/KIND TERMINALS AT THIS TIME.
SATELLITE LOOPS INDICATE THE SOUTHERN EDGE HAS MOVED LITTLE OVER THE PAST
COUPLE OF HOURS...HOWEVER THE WESTERN EDGE HAS BEEN ERODING OVER ILLINOIS.
GIVEN THE LOW LEVEL FLOW IS EXPECTED TO BACK AROUND TO THE WEST SOUTHWEST
WITH TIME...EXPECT THESE CEILINGS TO GRADUALLY ERODE FROM THE WEST...BUT IT
PROBABLY WON/T BE UNTIL LATE TONIGHT BEFORE THIS HAPPENS.
ONCE THE LOW CLOUDS CLEAR OUT...LINGERING LOW LEVEL MOISTURE WILL LEAD TO
SOME FOG FORMATION...ALTHOUGH CONFIDENCE ON VISIBILITY FORECASTS IS LOW
DUE TO QUESTIONS REVOLVING ON HOW FAST LOW CLOUDS CLEAR OUT. AT THIS TIME...IT
APPEARS THE BEST CHANCES FOR IFR VISIBILITY RESTRICTIONS WILL BE IN THE
KHUF/KBMG AREAS...WHICH ARE CLOSER TO THE CLEARING LINE AND LIGHTEST WINDS.
SURFACE WINDS AT OR BELOW 7 KTS TONIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/NIELD
SHORT TERM...JH
LONG TERM...SMF
AVIATION...JAS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
926 PM EST THU DEC 3 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 310 PM EST THU DEC 3 2015
DRY AND WARMER WEATHER WILL OCCUR THROUGH THE WEEKEND AS HIGH PRESSURE
OVER THE MIDDLE MISSISSIPPI VALLEY MOVES EAST ACROSS THE OHIO VALLEY
LATE TONIGHT AND FRIDAY AND TO SOUTHERN NEW ENGLAND OVER THE WEEKEND.
AN UPPER TROUGH WILL MOVE OUR WAY SUNDAY NIGHT AND MONDAY. BUT AT THE
MOMENT MODELS INDICATE MORE CLOUDS...BUT ONLY SLIGHT CHANCE OF SHOWERS
SOUTH AROUND SUNDAY NIGHT. SLIGHTLY WARMER AND DRY WEATHER WILL OCCUR
NEXT WEEK AS HIGH PRESSURE BUILDS ALONG THE ATLANTIC COAST.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 310 PM EST THU DEC 3 2015
SATELLITE INDICATES A LARGE AREA OF STRATUS OVER NORTH AND CENTRAL
SECTIONS...WHILE MOSTLY SUNNY SKIES HAVE CONTINUED ACROSS OUR SOUTH.
THE STATUS HAS BEEN CLEARING OVER WESTERN ILLINOIS....WHILE IT HAS
INCREASED A LITTLE ACROSS INDIANA.
EXPECT SOME CLEARING ACROSS ILLINOIS NEXT SEVERAL HOURS. HOWEVER RUC AND
NAM MODEL INDICATES POSSIBLE REDEVELOPMENT OF STRATUS AND FOG OVER
NORTH AND CENTRAL SECTIONS LATER TONIGHT. FOR NOW WILL KEEP SOME STRATUS
OVER NORTH AND CENTRAL SECTIONS OVERNIGHT...WHICH WOULD MINIMIZE THE
THREAT OF FOG. EVEN IF CLOUDS CLEAR...MODELS INDICATE SOME LOW LEVEL
SHEAR WHICH WOULD FAVOR STRATUS OVER FOG. SO FOR NOW WILL LEAVE OUT MENTION
OF FOG AS PARAMETERS ARE VERY IFFY. OVERNIGHT LOWS WILL BE IN THE MIDDLE
TO UPPER 20S WHICH IS CLOSE TO A MOS BLEND.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
ISSUED AT 310 PM EST THU DEC 3 2015
DRY AND WARMER WEATHER WILL OCCUR THIS WEEKEND AS HIGH PRESSURE
MOVES ON TO THE EAST AND MODELS BUILD AN UPPER RIDGE OVER THE
EASTERN U.S. MODEL SOUNDINGS INDICATE MOSTLY CLEAR SKIES THROUGH
SATURDAY NIGHT AND THEN INCREASING CLOUDS SUNDAY AS AN UPPER TROUGH
MOVES OUR WAY.
MOST MODELS KEEP US DRY THROUGH SUNDAY AFTERNOON...WHILE THE EURO
INDICATES TRACE PRECIP AMOUNTS WEST AND SOUTH LATE SUNDAY. WILL GO
WITH CONSENSUS AND KEEP EVERYTHING DRY THROUGH SUNDAY. HIGHS WILL
BE IN THE UPPER 40S TO LOWER 50S FRIDAY AND SUNDAY AND IN THE LOWER
TO MIDDLE 50S SATURDAY. LOWS WILL BE IN THE UPPER 20S TO AROUND 30
FRIDAY NIGHT AND IN THE LOWER 30S SATURDAY NIGHT. WENT SLIGHTLY ABOVE
A MOS BLEND ON HIGHS WITH SOME SUN AND WARM ADVECTION. OTHERWISE...STAYED
CLOSE TO A MOS BLEND ON LOWS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 240 PM EST THU DEC 3 2015
ENSEMBLES BRING AN UPPER WAVE ACROSS THE AREA SUNDAY NIGHT AS A WEAK
SURFACE SYSTEM SLIDES EAST ACROSS THE TENNESSEE VALLEY. MOISTURE
WILL BE LIMITED...HOWEVER THE FORCING IS ENOUGH TO CONTINUE TO CARRY
WEAK CHANCES OF RAIN SHOWERS ACROSS THE SOUTHERN TIER.
WEAK RIDGING WILL PREVAIL THROUGHOUT MOST OF THE EXTENDED WITH DRY
CONDITIONS AND WARMER THAN NORMAL TEMPERATURES THROUGHOUT NEXT
WEEK.
&&
.AVIATION /DISCUSSION FOR THE 040300Z KIND TAF UPDATE/...
ISSUED AT 926 PM EST THU DEC 3 2015
NO SIGNIFICANT CHANGES MADE TO THE FORECAST AT THIS TIME. PREVIOUS
DISCUSSION FOLLOWS.
EXTENSIVE AREA OF MVFR CEILINGS 012-020 COVERS MOST OF NORTHERN AND
CENTRAL INDIANA...AFFECTING THE KLAF/KHUF/KIND TERMINALS AT THIS TIME.
SATELLITE LOOPS INDICATE THE SOUTHERN EDGE HAS MOVED LITTLE OVER THE PAST
COUPLE OF HOURS...HOWEVER THE WESTERN EDGE HAS BEEN ERODING OVER ILLINOIS.
GIVEN THE LOW LEVEL FLOW IS EXPECTED TO BACK AROUND TO THE WEST SOUTHWEST
WITH TIME...EXPECT THESE CEILINGS TO GRADUALLY ERODE FROM THE WEST...BUT IT
PROBABLY WON/T BE UNTIL LATE TONIGHT BEFORE THIS HAPPENS.
ONCE THE LOW CLOUDS CLEAR OUT...LINGERING LOW LEVEL MOISTURE WILL LEAD TO
SOME FOG FORMATION...ALTHOUGH CONFIDENCE ON VISIBILITY FORECASTS IS LOW
DUE TO QUESTIONS REVOLVING ON HOW FAST LOW CLOUDS CLEAR OUT. AT THIS TIME...IT
APPEARS THE BEST CHANCES FOR IFR VISIBILITY RESTRICTIONS WILL BE IN THE
KHUF/KBMG AREAS...WHICH ARE CLOSER TO THE CLEARING LINE AND LIGHTEST WINDS.
SURFACE WINDS AT OR BELOW 7 KTS TONIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...JH
LONG TERM...SMF
AVIATION...JAS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
338 PM EST WED DEC 2 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 220 PM EST WED DEC 2 2015
AN EXITING UPPER LEVEL SYSTEM WILL KEEP CHANCES FOR SNOW AROUND THIS
EVENING. HIGH PRESSURE WILL THEN BUILD IN AND PROVIDE DRY CONDITIONS
INTO NEXT WEEK. COOL TEMPERATURES THURSDAY WILL GIVE WAY TO ABOVE
NORMAL READINGS FRIDAY INTO NEXT WEEK.
&&
.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 220 PM EST WED DEC 2 2015
SCATTERED SNOW /AND SOME RAIN/ SHOWERS WERE ACROSS ILLINOIS AND
CENTRAL INDIANA THIS AFTERNOON AS AN UPPER LOW WAS MOVING INTO
NORTHERN ILLINOIS.
AS THE UPPER LOW MOVES EAST...THESE SHOWERS WILL WORK THERE WAY
ACROSS CENTRAL INDIANA. WILL KEEP HIGH CHANCE POPS ACROSS THE AREA
BEFORE 00Z. THERE WILL BE A MIX OF RAIN AND SNOW...BUT EXPECT SNOW
TO BECOME MORE PREDOMINANT AS THE AFTERNOON PROGRESSES AS COLDER
AIR WORKS ITS WAY IN.
AT 00Z...HI RES SHORT TERM MODELS STILL SHOW SCATTERED SNOW
SHOWERS ACROSS THE AREA WITH THE UPPER LOW STILL ACROSS NORTHERN
INDIANA AND TROUGHING EXTENDING SOUTHWEST ACROSS THE AREA. IN
ADDITION...THE DERIVED SNOW SQUALL PARAMETER STILL INDICATES THE
THREAT OF SNOW SHOWERS ACROSS NORTHERN SECTIONS.
THUS WILL RAISE MOS POPS AND GO CHANCE CATEGORY POPS ALL AREAS AT
00Z. WILL GRADUALLY LOWER AND END THESE FROM WEST TO EAST DURING
THE EVENING AS THE SYSTEM EXITS THE AREA.
CLOUDS WILL BEGIN TO DECREASE OVERNIGHT AS DRIER AIR WORKS IN BEHIND
THE LOW. MOS IS USUALLY TOO FAST WITH CLEARING SO WENT A LITTLE
SLOWER...BUT MOST OF THE AREA WILL BECOME PARTLY CLOUDY BEFORE
SUNRISE. THIS SHOULD ALLOW READINGS TO STILL GET DOWN TO MOS NUMBERS
FOR LOW TEMPERATURES MOST AREAS.
&&
.SHORT TERM.../THURSDAY THROUGH SATURDAY/
ISSUED AT 220 PM EST WED DEC 2 2015
FOCUS IS ON SKY AND TEMPERATURES. MODELS ARE CLOSE ENOUGH THAT A
BLEND WAS USED.
STILL EXPECT SOME CLOUDS ACROSS THE AREA THURSDAY
MORNING...ESPECIALLY NORTHEAST. AS DRIER AIR AND HIGH PRESSURE BUILD
IN DURING THE DAY...EXPECT THESE CLOUDS TO DIMINISH. THE INCREASING
AMOUNT OF SUNSHINE SHOULD ALLOW READINGS TO GET NEAR MOS NUMBERS FOR
HIGHS.
HIGH PRESSURE AT THE SURFACE AND RIDGING ALOFT WILL KEEP THE AREA
DRY THROUGH SATURDAY. THE ATMOSPHERE DRIES OUT EVEN MORE WITH THE
SUBSIDENCE SO EXPECT MOSTLY CLEAR CONDITIONS THURSDAY NIGHT THROUGH
SATURDAY.
MAV MOS LOOKS REASONABLE FOR TEMPERATURES MOST PERIODS GIVEN
EXPECTED CONDITIONS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 201 PM EST WED DEC 2 2015
MAINLY DRY WEATHER EXPECTED DURING THIS PERIOD AS WEAK RIDGING AND
POORLY ORGANIZED HIGH PRESSURE IS EXPECTED TO BE IN PLACE ACROSS
THE REGION.
ECMWF AND GFS BOTH SUGGEST RIDGING AND HIGH PRESSURE REMAIN IN
PLACE ON SATURDAY THROUGH MONDAY...PROMOTING A DRY COLUMN. BY
MONDAY NIGHT THROUGH WEDNESDAY...THE GFS AND ECMWF SUGGEST AN
UPPER SYSTEM MOVING THROUGH THE TENNESSEE AND OHIO VALLEYS TO
APPALACHIA. AT THIS TIME MOISTURE APPEARS LIMITED. GIVEN THE
STRENGTH OF THE UPPER SYSTEM...A SMALL CHANCE FOR PRECIP APPEARS
WARRANTED...BUT SUPERBLEND KEEPS ALL POPS LESS THAN 20. THUS HAVE
TRENDED TOWARD A DRY FORECAST OVERALL FOR NOW...BUT WOULD NOT BE
SURPRISED TO SEE POPS INCREASE AS THIS FORECAST PROGRESSES DUE TO
THE RELATIVE STRENGTH OF THE UPPER SUPPORT.
&&
.AVIATION /DISCUSSION FOR THE 021800Z TAFS/...
ISSUED AT 334 PM EST WED DEC 2 2015
2030Z UPDATE...BASED ON CURRENT OBSERVATIONS AND
TRENDS...CONDITIONS ARE DETERIORATING TO MVFR AND LOWER AT TIMES
IN SOME OF THE MORE MODERATE SNOW SHOWERS. BASED ON THE REGIONAL
RADAR MOSAIC EXPECT THESE CONDITIONS TO CONTINUE THROUGH AT LEAST
00Z AND UPDATED MANY OF THE TERMINALS TO REFLECT CURRENT MVFR
TRENDS AND ADDED AN IFR TEMPO GROUP FOR THE NEXT 2 TO 3 HOURS.
CONDITIONS WILL ONLY IMPROVE TO MVFR ONCE THE SNOW SHOWERS ABATE
LATER THIS EVENING AND VFR CONDITIONS ARE STILL NOT EXPECTED UNTIL
LATE THURSDAY MORNING. PREVIOUS DISCUSSION FOLLOWS.
MVFR CONDITIONS WITH BRIEF IFR CONDITIONS WILL BE POSSIBLE THIS
AFTERNOON AND EARLY THIS EVENING AS A SHORT WAVE IS EXPECTED TO
PUSH ACROSS THE TAF SITES.
RADAR SHOWS THE NEXT SHORT WAVE...OVER CENTRAL ILLINOIS...POISED
TO PUSH EAST ACROSS CENTRAL INDIANA. HRRR INDICATES THAT THIS
FEATURE SHOULD PASS TO OUR EAST BY 00Z. FORECAST SOUNDINGS SHOW
BEST FORCING ENDING BY 00Z. THUS HAVE MENTION PREVAILING PRECIP
UNTIL THIS TIME...TAPERING OFF MAINLY SHORTLY AFTER 00Z. TIME
HEIGHTS SHOW LINGERING LOWER LEVEL MOISTURE OVERNIGHT WHILE
FORECAST SOUNDINGS BEGIN TO DRY THE LOWER PARTS OF THE COLUMN
AFTER 06Z. FOR NOW WILL TREND TOWARD MVFR CIGS OVERNIGHT AS SOME
TRAPPED MOISTURE SHOULD LINGER. A RETURN TO VFR IS EXPECTED BY
LATE THURSDAY MORNING AS RIDGING BEGINS TO BUILD ACROSS THE
REGION.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50
SHORT TERM...50
LONG TERM....PUMA
AVIATION...SMF/PUMA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
220 PM EST WED DEC 2 2015
.UPDATE...
THE SYNOPSIS...NEAR TERM...AND SHORT TERM SECTIONS HAVE BEEN
UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 220 PM EST WED DEC 2 2015
AN EXITING UPPER LEVEL SYSTEM WILL KEEP CHANCES FOR SNOW AROUND THIS
EVENING. HIGH PRESSURE WILL THEN BUILD IN AND PROVIDE DRY CONDITIONS
INTO NEXT WEEK. COOL TEMPERATURES THURSDAY WILL GIVE WAY TO ABOVE
NORMAL READINGS FRIDAY INTO NEXT WEEK.
&&
.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 220 PM EST WED DEC 2 2015
SCATTERED SNOW /AND SOME RAIN/ SHOWERS WERE ACROSS ILLINOIS AND
CENTRAL INDIANA THIS AFTERNOON AS AN UPPER LOW WAS MOVING INTO
NORTHERN ILLINOIS.
AS THE UPPER LOW MOVES EAST...THESE SHOWERS WILL WORK THERE WAY
ACROSS CENTRAL INDIANA. WILL KEEP HIGH CHANCE POPS ACROSS THE AREA
BEFORE 00Z. THERE WILL BE A MIX OF RAIN AND SNOW...BUT EXPECT SNOW
TO BECOME MORE PREDOMINANT AS THE AFTERNOON PROGRESSES AS COLDER
AIR WORKS ITS WAY IN.
AT 00Z...HI RES SHORT TERM MODELS STILL SHOW SCATTERED SNOW
SHOWERS ACROSS THE AREA WITH THE UPPER LOW STILL ACROSS NORTHERN
INDIANA AND TROUGHING EXTENDING SOUTHWEST ACROSS THE AREA. IN
ADDITION...THE DERIVED SNOW SQUALL PARAMETER STILL INDICATES THE
THREAT OF SNOW SHOWERS ACROSS NORTHERN SECTIONS.
THUS WILL RAISE MOS POPS AND GO CHANCE CATEGORY POPS ALL AREAS AT
00Z. WILL GRADUALLY LOWER AND END THESE FROM WEST TO EAST DURING
THE EVENING AS THE SYSTEM EXITS THE AREA.
CLOUDS WILL BEGIN TO DECREASE OVERNIGHT AS DRIER AIR WORKS IN BEHIND
THE LOW. MOS IS USUALLY TOO FAST WITH CLEARING SO WENT A LITTLE
SLOWER...BUT MOST OF THE AREA WILL BECOME PARTLY CLOUDY BEFORE
SUNRISE. THIS SHOULD ALLOW READINGS TO STILL GET DOWN TO MOS NUMBERS
FOR LOW TEMPERATURES MOST AREAS.
&&
.SHORT TERM.../THURSDAY THROUGH SATURDAY/
ISSUED AT 220 PM EST WED DEC 2 2015
FOCUS IS ON SKY AND TEMPERATURES. MODELS ARE CLOSE ENOUGH THAT A
BLEND WAS USED.
STILL EXPECT SOME CLOUDS ACROSS THE AREA THURSDAY
MORNING...ESPECIALLY NORTHEAST. AS DRIER AIR AND HIGH PRESSURE BUILD
IN DURING THE DAY...EXPECT THESE CLOUDS TO DIMINISH. THE INCREASING
AMOUNT OF SUNSHINE SHOULD ALLOW READINGS TO GET NEAR MOS NUMBERS FOR
HIGHS.
HIGH PRESSURE AT THE SURFACE AND RIDGING ALOFT WILL KEEP THE AREA
DRY THROUGH SATURDAY. THE ATMOSPHERE DRIES OUT EVEN MORE WITH THE
SUBSIDENCE SO EXPECT MOSTLY CLEAR CONDITIONS THURSDAY NIGHT THROUGH
SATURDAY.
MAV MOS LOOKS REASONABLE FOR TEMPERATURES MOST PERIODS GIVEN
EXPECTED CONDITIONS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 201 PM EST WED DEC 2 2015
MAINLY DRY WEATHER EXPECTED DURING THIS PERIOD AS WEAK RIDGING AND
POORLY ORGANIZED HIGH PRESSURE IS EXPECTED TO BE IN PLACE ACROSS
THE REGION.
ECMWF AND GFS BOTH SUGGEST RIDGING AND HIGH PRESSURE REMAIN IN
PLACE ON SATURDAY THROUGH MONDAY...PROMOTING A DRY COLUMN. BY
MONDAY NIGHT THROUGH WEDNESDAY...THE GFS AND ECMWF SUGGEST AN
UPPER SYSTEM MOVING THROUGH THE TENNESSEE AND OHIO VALLEYS TO
APPALACHIA. AT THIS TIME MOISTURE APPEARS LIMITED. GIVEN THE
STRENGTH OF THE UPPER SYSTEM...A SMALL CHANCE FOR PRECIP APPEARS
WARRANTED...BUT SUPERBLEND KEEPS ALL POPS LESS THAN 20. THUS HAVE
TRENDED TOWARD A DRY FORECAST OVERALL FOR NOW...BUT WOULD NOT BE
SURPRISED TO SEE POPS INCREASE AS THIS FORECAST PROGRESSES DUE TO
THE RELATIVE STRENGTH OF THE UPPER SUPPORT.
&&
.AVIATION /DISCUSSION FOR THE 021800Z TAFS/...
ISSUED AT 1235 PM EST WED DEC 2 2015
MVFR CONDITIONS WITH BRIEF IFR CONDITIONS WILL BE POSSIBLE THIS
AFTERNOON AND EARLY THIS EVENING AS A SHORT WAVE IS EXPECTED TO
PUSH ACROSS THE TAF SITES.
RADAR SHOWS THE NEXT SHORT WAVE...OVER CENTRAL ILLINOIS...POISED
TO PUSH EAST ACROSS CENTRAL INDIANA. HRRR INDICATES THAT THIS
FEATURE SHOULD PASS TO OUR EAST BY 00Z. FORECAST SOUNDINGS SHOW
BEST FORCING ENDING BY 00Z. THUS HAVE MENTION PREVAILING PRECIP
UNTIL THIS TIME...TAPERING OFF MAINLY SHORTLY AFTER 00Z. TIME
HEIGHTS SHOW LINGERING LOWER LEVEL MOISTURE OVERNIGHT WHILE
FORECAST SOUNDINGS BEGIN TO DRY THE LOWER PARTS OF THE COLUMN
AFTER 06Z. FOR NOW WILL TREND TOWARD MVFR CIGS OVERNIGHT AS SOME
TRAPPED MOISTURE SHOULD LINGER. A RETURN TO VFR IS EXPECTED BY
LATE THURSDAY MORNING AS RIDGING BEGINS TO BUILD ACROSS THE
REGION.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50
SHORT TERM...50
LONG TERM....PUMA
AVIATION...JP
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
202 PM EST WED DEC 2 2015
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 333 AM EST WED DEC 2 2015
A PRECIP MIX OF RAIN AND SNOW WILL BE POSSIBLE TODAY AND THIS
EVENING AS AN UPPER LOW TRACKS FROM THE GREAT LAKES REGION INTO
THE OHIO VALLEY. NORTHERN PORTIONS OF THE AREA CAN EXPECT MAINLY
SNOW...WHILE CENTRAL AND SOUTHERN PORTIONS WILL RECEIVE A MIX OF
RAIN/SNOW AND JUST RAIN. THE DISTURBANCE WILL QUICKLY MOVE OUT
TONIGHT...AND DRY CONDITIONS WILL PREVAIL THROUGH THE WEEKEND. THE
NEXT CHANCE FOR RAIN WILL BE ON SUNDAY AND MONDAY AS ANOTHER UPPER
LOW ENTERS THE REGION.
&&
.NEAR TERM /REST OF TODAY AND TONIGHT/...
ISSUED AT 939 AM EST WED DEC 2 2015
FIRST BAND OF PRECIPITATION IS MOVING ACROSS THE WESTERN FORECAST
AREA AT THE MOMENT. 850MB FRONTOGENETICAL FORCING IS HELPING PRODUCE
THIS BAND. BASED ON SURFACE OBSERVATIONS AND WEBCAMS...IT APPEARS
THAT THIS IS JUST SOME LIGHT RAIN/SNOW MIX WITH VERY LIGHT AMOUNTS.
EXPECT MORE PRECIPITATION TO DEVELOP THIS AFTERNOON. TWEAKED POPS
BUT MAY HAVE TO MAKE MORE ADJUSTMENTS LATER AS SHORT TERM MODELS
HINTING AT MORE COVERAGE SOUTH. ALSO BASED ON THE LATEST
DATA...RAISED POPS A BIT DURING THE EARLY EVENING DUE TO SLOWER
TIMING.
MADE MINOR MODIFICATIONS TO TEMPERATURES FOR NOW.
PREVIOUS DISCUSSION FOLLOWS...
THE MAIN FOCUS OF THE NEAR TERM PERIOD WILL BE PRECIP TYPE AND
TIMING AS AN UPPER LOW MOVES INTO THE OHIO VALLEY.
MODELS ARE IN AGREEMENT WITH DRY SLOT OVER MOST OF CENTRAL INDIANA
THROUGH WED 12Z. HOWEVER...AS AFOREMENTIONED LOW DIPS FARTHER INTO
NORTHERN ILLINOIS THIS MORNING...PRECIPITATION WILL SPREAD ACROSS
CENTRAL INDIANA FROM WEST TO EAST. FORCING REMAINS WEAK IN THE
LOWER LEVELS...BUT Q VECTOR CONVERGENCE IN THE 700-500MB LAYERS IS
QUITE IMPRESSIVE FROM WED 12Z-21Z. AS A RESULT...LIKELY POPS ARE
STILL JUSTIFIED ACROSS THE NORTHERN COUNTIES DURING THE EARLY
AFTERNOON HOURS.
PRECIPITATION SHOULD INITIALLY START OUT IN THE FORM OF A
RAIN/SNOW MIX...BUT AS 850 MB TEMPS DROP FROM -1C TO -9C THROUGH
THE COURSE OF THE DAY...THERE WILL BE A TRANSITION TO ALL SNOW
FROM NORTHWEST TO SOUTHEAST ACROSS THE FORECAST AREA. THE WARMER
SURFACE TEMPS IN THE LOW TO MID 40S ACROSS THE SOUTHERN COUNTIES
WILL MAKE IT TOUGH FOR ANYTHING OTHER THAN RAIN SHOWERS ACROSS
THAT AREA THOUGH THIS AFTERNOON.
AS UPPER LOW MOVES FARTHER SOUTHEAST...FORCING WILL QUICKLY WEAKEN
BY THIS EVENING. WESTERN COUNTIES SHOULD START SEEING SOME
CLEARING AS EARLY AS THU 00Z WITH PRECIP ENDING ACROSS ALL OF
CENTRAL INDIANA BY MIDNIGHT. AS TEMPS DROP IN THE LOWER LEVELS
THIS EVENING...THE SOUTHERN COUNTIES CAN EXPECT RAIN TO TRANSITION
TO RAIN/SNOW AT THE TAIL END OF THE EVENT WITH ALL SNOW OVER THE
NORTHEAST COUNTIES. TOTAL SNOWFALL AMOUNTS SHOULD BE AROUND A
HALF-INCH ACROSS THE NORTHERN COUNTIES.
TRENDED TOWARD MET MOS GUIDANCE FOR DURATION OF NEAR TERM SINCE IT
WAS COOLER FOR DAYTIME HIGHS AND SLIGHTLY WARMER FOR TONIGHT/S
LOWS/WHICH WILL BE IMPACTED BY LINGERING CLOUDS/. DAYTIME HIGHS
WILL BE IN THE UPPER 30S/MID 40S...AND OVERNIGHT LOWS WILL BE IN
THE UPPER 20S.
&&
.SHORT TERM /TOMORROW THROUGH FRIDAY NIGHT/...
ISSUED AT 333 AM EST WED DEC 2 2015
BENIGN WEATHER PATTERN WILL PREVAIL FOR DURATION OF SHORT TERM
PERIOD AS HIGH PRESSURE ALOFT AND AT THE SURFACE ENCOMPASSES MUCH
OF THE CENTRAL AND EASTERN U.S. SO...DRY CONDITIONS CAN BE
EXPECTED WITH A WEAK WARMING TREND THROUGH THE PERIOD. HIGHS WILL
START OUT IN THE LOW 40S FOR THURSDAY...BUT INCREASE INTO THE
UPPER 40S/LOW 50S BY THE WEEKEND. MEANWHILE...OVERNIGHT LOWS WILL
BE IN THE UPPER 20S. STUCK CLOSE TO GUIDANCE FOR THE PERIOD.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 201 PM EST WED DEC 2 2015
MAINLY DRY WEATHER EXPECTED DURING THIS PERIOD AS WEAK RIDGING AND
POORLY ORGANIZED HIGH PRESSURE IS EXPECTED TO BE IN PLACE ACROSS
THE REGION.
ECMWF AND GFS BOTH SUGGEST RIDGING AND HIGH PRESSURE REMAIN IN
PLACE ON SATURDAY THROUGH MONDAY...PROMOTING A DRY COLUMN. BY
MONDAY NIGHT THROUGH WEDNESDAY...THE GFS AND ECMWF SUGGEST AN
UPPER SYSTEM MOVING THROUGH THE TENNESSEE AND OHIO VALLEYS TO
APPALACHIA. AT THIS TIME MOISTURE APPEARS LIMITED. GIVEN THE
STRENGTH OF THE UPPER SYSTEM...A SMALL CHANCE FOR PRECIP APPEARS
WARRANTED...BUT SUPERBLEND KEEPS ALL POPS LESS THAN 20. THUS HAVE
TRENDED TOWARD A DRY FORECAST OVERALL FOR NOW...BUT WOULD NOT BE
SURPRISED TO SEE POPS INCREASE AS THIS FORECAST PROGRESSES DUE TO
THE RELATIVE STRENGTH OF THE UPPER SUPPORT.
&&
.AVIATION /DISCUSSION FOR THE 021800Z TAFS/...
ISSUED AT 1235 PM EST WED DEC 2 2015
MVFR CONDITIONS WITH BRIEF IFR CONDITIONS WILL BE POSSIBLE THIS
AFTERNOON AND EARLY THIS EVENING AS A SHORT WAVE IS EXPECTED TO
PUSH ACROSS THE TAF SITES.
RADAR SHOWS THE NEXT SHORT WAVE...OVER CENTRAL ILLINOIS...POISED
TO PUSH EAST ACROSS CENTRAL INDIANA. HRRR INDICATES THAT THIS
FEATURE SHOULD PASS TO OUR EAST BY 00Z. FORECAST SOUNDINGS SHOW
BEST FORCING ENDING BY 00Z. THUS HAVE MENTION PREVAILING PRECIP
UNTIL THIS TIME...TAPERING OFF MAINLY SHORTLY AFTER 00Z. TIME
HEIGHTS SHOW LINGERING LOWER LEVEL MOISTURE OVERNIGHT WHILE
FORECAST SOUNDINGS BEGIN TO DRY THE LOWER PARTS OF THE COLUMN
AFTER 06Z. FOR NOW WILL TREND TOWARD MVFR CIGS OVERNIGHT AS SOME
TRAPPED MOISTURE SHOULD LINGER. A RETURN TO VFR IS EXPECTED BY
LATE THURSDAY MORNING AS RIDGING BEGINS TO BUILD ACROSS THE
REGION.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...TDUD
NEAR TERM...TDUD/50
SHORT TERM...TDUD
LONG TERM....PUMA
AVIATION...JP
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1235 PM EST WED DEC 2 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 333 AM EST WED DEC 2 2015
A PRECIP MIX OF RAIN AND SNOW WILL BE POSSIBLE TODAY AND THIS
EVENING AS AN UPPER LOW TRACKS FROM THE GREAT LAKES REGION INTO
THE OHIO VALLEY. NORTHERN PORTIONS OF THE AREA CAN EXPECT MAINLY
SNOW...WHILE CENTRAL AND SOUTHERN PORTIONS WILL RECEIVE A MIX OF
RAIN/SNOW AND JUST RAIN. THE DISTURBANCE WILL QUICKLY MOVE OUT
TONIGHT...AND DRY CONDITIONS WILL PREVAIL THROUGH THE WEEKEND. THE
NEXT CHANCE FOR RAIN WILL BE ON SUNDAY AND MONDAY AS ANOTHER UPPER
LOW ENTERS THE REGION.
&&
.NEAR TERM /REST OF TODAY AND TONIGHT/...
ISSUED AT 939 AM EST WED DEC 2 2015
FIRST BAND OF PRECIPITATION IS MOVING ACROSS THE WESTERN FORECAST
AREA AT THE MOMENT. 850MB FRONTOGENETICAL FORCING IS HELPING PRODUCE
THIS BAND. BASED ON SURFACE OBSERVATIONS AND WEBCAMS...IT APPEARS
THAT THIS IS JUST SOME LIGHT RAIN/SNOW MIX WITH VERY LIGHT AMOUNTS.
EXPECT MORE PRECIPITATION TO DEVELOP THIS AFTERNOON. TWEAKED POPS
BUT MAY HAVE TO MAKE MORE ADJUSTMENTS LATER AS SHORT TERM MODELS
HINTING AT MORE COVERAGE SOUTH. ALSO BASED ON THE LATEST
DATA...RAISED POPS A BIT DURING THE EARLY EVENING DUE TO SLOWER
TIMING.
MADE MINOR MODIFICATIONS TO TEMPERATURES FOR NOW.
PREVIOUS DISCUSSION FOLLOWS...
THE MAIN FOCUS OF THE NEAR TERM PERIOD WILL BE PRECIP TYPE AND
TIMING AS AN UPPER LOW MOVES INTO THE OHIO VALLEY.
MODELS ARE IN AGREEMENT WITH DRY SLOT OVER MOST OF CENTRAL INDIANA
THROUGH WED 12Z. HOWEVER...AS AFOREMENTIONED LOW DIPS FARTHER INTO
NORTHERN ILLINOIS THIS MORNING...PRECIPITATION WILL SPREAD ACROSS
CENTRAL INDIANA FROM WEST TO EAST. FORCING REMAINS WEAK IN THE
LOWER LEVELS...BUT Q VECTOR CONVERGENCE IN THE 700-500MB LAYERS IS
QUITE IMPRESSIVE FROM WED 12Z-21Z. AS A RESULT...LIKELY POPS ARE
STILL JUSTIFIED ACROSS THE NORTHERN COUNTIES DURING THE EARLY
AFTERNOON HOURS.
PRECIPITATION SHOULD INITIALLY START OUT IN THE FORM OF A
RAIN/SNOW MIX...BUT AS 850 MB TEMPS DROP FROM -1C TO -9C THROUGH
THE COURSE OF THE DAY...THERE WILL BE A TRANSITION TO ALL SNOW
FROM NORTHWEST TO SOUTHEAST ACROSS THE FORECAST AREA. THE WARMER
SURFACE TEMPS IN THE LOW TO MID 40S ACROSS THE SOUTHERN COUNTIES
WILL MAKE IT TOUGH FOR ANYTHING OTHER THAN RAIN SHOWERS ACROSS
THAT AREA THOUGH THIS AFTERNOON.
AS UPPER LOW MOVES FARTHER SOUTHEAST...FORCING WILL QUICKLY WEAKEN
BY THIS EVENING. WESTERN COUNTIES SHOULD START SEEING SOME
CLEARING AS EARLY AS THU 00Z WITH PRECIP ENDING ACROSS ALL OF
CENTRAL INDIANA BY MIDNIGHT. AS TEMPS DROP IN THE LOWER LEVELS
THIS EVENING...THE SOUTHERN COUNTIES CAN EXPECT RAIN TO TRANSITION
TO RAIN/SNOW AT THE TAIL END OF THE EVENT WITH ALL SNOW OVER THE
NORTHEAST COUNTIES. TOTAL SNOWFALL AMOUNTS SHOULD BE AROUND A
HALF-INCH ACROSS THE NORTHERN COUNTIES.
TRENDED TOWARD MET MOS GUIDANCE FOR DURATION OF NEAR TERM SINCE IT
WAS COOLER FOR DAYTIME HIGHS AND SLIGHTLY WARMER FOR TONIGHT/S
LOWS/WHICH WILL BE IMPACTED BY LINGERING CLOUDS/. DAYTIME HIGHS
WILL BE IN THE UPPER 30S/MID 40S...AND OVERNIGHT LOWS WILL BE IN
THE UPPER 20S.
&&
.SHORT TERM /TOMORROW THROUGH FRIDAY NIGHT/...
ISSUED AT 333 AM EST WED DEC 2 2015
BENIGN WEATHER PATTERN WILL PREVAIL FOR DURATION OF SHORT TERM
PERIOD AS HIGH PRESSURE ALOFT AND AT THE SURFACE ENCOMPASSES MUCH
OF THE CENTRAL AND EASTERN U.S. SO...DRY CONDITIONS CAN BE
EXPECTED WITH A WEAK WARMING TREND THROUGH THE PERIOD. HIGHS WILL
START OUT IN THE LOW 40S FOR THURSDAY...BUT INCREASE INTO THE
UPPER 40S/LOW 50S BY THE WEEKEND. MEANWHILE...OVERNIGHT LOWS WILL
BE IN THE UPPER 20S. STUCK CLOSE TO GUIDANCE FOR THE PERIOD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY NIGHT/...
ISSUED AT 322 AM EST WED DEC 2 2015
ITS SHAPING UP TO BE A MILD AND DRY WEEKEND ACROSS CENTRAL INDIANA
PER OPERATIONAL MODELS AND ENSEMBLES...AS SURFACE HIGH PRESSURE
SETTLES EAST ACROSS THE APPALACHIANS. SHOULD ONLY SEE HIGH CLOUDS IN
FAST SOUTHWEST FLOW AHEAD OF AN UPPER SYSTEM MOVING FROM THE ROCKIES
TO THE CENTRAL AND SOUTHERN PLAINS.
MODEL THERMAL PROFILES AND LITTLE CLOUD COVER SUPPORTS THE ABOVE
NORMAL REGIONAL BLEND TEMPERATURES WITH HIGHS IN THE UPPER 40S NORTH
TO THE LOWER 50S SOUTH BOTH SATURDAY AND SUNDAY. BLEND LOWS IN THE
UPPER 20S AND LOWER 30S SATURDAY NIGHT ALSO LOOK OK.
THE 00Z GFS AND 00Z ECMWF WERE HAVE ISSUES WITH REGARDS TO TIMING OF
THE UPPER TROUGH THAT WAS MENTIONED ABOVE. THE EURO IS CONTINUING
ITS FASTER TREND WITH THE TROUGH. THE GEFS WAS AN IN BETWEEN
COMPROMISE. MEANWHILE...THE POPS OF THE REGIONAL BLEND SEEMED TO
FAVOR THE FASTER EURO AND GEFS. THE 00Z ECMWF AND REGIONAL BLEND
BOTH HAVE SMALL POPS/QPF ACROSS OUR SOUTHWESTERN COUNTIES SUNDAY
NIGHT AND SMALL POPS CONTINUING THROUGH MONDAY NIGHT...MAINLY SOUTH.
WITH THE MODEL TIMING DIFFERENCES...NOT CONFIDENT ENOUGH TO MAKE ANY
CHANGES. WITH LITTLE CHANGE IN THE LOW LEVEL THERMAL
PROFILE...TEMPERATURES SHOULD REMAIN ABOVE NORMAL AND FAVOR ALL RAIN
SHOWERS.
SURFACE HIGH PRESSURE WILL TAKE OVER IN THE WAKE OF THE UPPER TROUGH
WHICH SHOULD LEAD TO MORE DRY WEATHER BY TUESDAY.
&&
.AVIATION /DISCUSSION FOR THE 021800Z TAFS/...
ISSUED AT 1235 PM EST WED DEC 2 2015
MVFR CONDITIONS WITH BRIEF IFR CONDITIONS WILL BE POSSIBLE THIS
AFTERNOON AND EARLY THIS EVENING AS A SHORT WAVE IS EXPECTED TO
PUSH ACROSS THE TAF SITES.
RADAR SHOWS THE NEXT SHORT WAVE...OVER CENTRAL ILLINOIS...POISED
TO PUSH EAST ACROSS CENTRAL INDIANA. HRRR INDICATES THAT THIS
FEATURE SHOULD PASS TO OUR EAST BY 00Z. FORECAST SOUNDINGS SHOW
BEST FORCING ENDING BY 00Z. THUS HAVE MENTION PREVAILING PRECIP
UNTIL THIS TIME...TAPERING OFF MAINLY SHORTLY AFTER 00Z. TIME
HEIGHTS SHOW LINGERING LOWER LEVEL MOISTURE OVERNIGHT WHILE
FORECAST SOUNDINGS BEGIN TO DRY THE LOWER PARTS OF THE COLUMN
AFTER 06Z. FOR NOW WILL TREND TOWARD MVFR CIGS OVERNIGHT AS SOME
TRAPPED MOISTURE SHOULD LINGER. A RETURN TO VFR IS EXPECTED BY
LATE THURSDAY MORNING AS RIDGING BEGINS TO BUILD ACROSS THE
REGION.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...TDUD
NEAR TERM...TDUD/50
SHORT TERM...TDUD
LONG TERM...MK
AVIATION...JP
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1122 PM CST TUE DEC 1 2015
.SYNOPSIS...
ISSUED AT 315 PM CST TUE DEC 1 2015
12Z UA ANALYSIS HAS AN 850MB LOW IN SOUTHWEST MINNESOTA WITH AN 850
MB COLD FRONT FROM UPPER MICHIGAN...THROUGH INDIANA...AND INTO
NORTHEAST TEXAS. A TROF RAN FROM THE LOW INTO SOUTHWEST KANSAS.
SATELLITE AND RADAR TRENDS SHOW WRAP AROUND CLOUDS FROM THE STORM
SYSTEM MOVING EAST ACROSS IOWA WITH SNOW SHOWERS DEVELOPING. LITTLE
IF ANY CLOUDS RAN FROM NORTHEAST ILLINOIS INTO THE SOUTHERN PLAINS.
18Z SFC DATA HAS A LOW IN SOUTHWEST MINNESOTA NEAR KRWF. THE MAIN
FRONT RAN EAST FROM THE LOW ACROSS WISCONSIN AND THEN SOUTH INTO
OHIO AND THEN MISSISSIPPI. DEW POINTS WERE IN THE 30S AND HIGHER
EAST OF THE MISSISSIPPI AND INTO THE OHIO VALLEY. DEW POINTS WERE IN
THE 20S ACROSS THE CENTRAL AND NORTHERN PLAINS.
&&
.SHORT TERM...(LATE THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 315 PM CST TUE DEC 1 2015
RADAR TRENDS SHOW ISOLATED TO SCATTERED SNOW SHOWERS HAVE BROKEN OUT
WEST OF A FREEPORT TO OTTUMWA LINE. BASED ON RAP TRENDS...THESE SNOW
SHOWERS WILL CONTINUE THROUGH THE LATE AFTERNOON AND INTO THE EARLY
EVENING HOURS GENERALLY WEST OF A KRFD TO KIRK LINE. A DUSTING IS
POSSIBLE ON THE GRASS AND ELEVATED SURFACES. PAVEMENT TEMPERATURES
ARE ABOVE FREEZING SO THE SNOW SHOULD MELT ON THE ROADS.
THERE MAY BE A LULL IN ACTIVITY LATE THIS EVENING BEFORE NEW SNOW
SHOWERS DEVELOP ACROSS THE AREA AS THE UPPER LOW MOVES INTO
WISCONSIN. THE BETTER CHANCES GENERALLY LOOK TO BE ALONG/NORTH OF I-
80 AND ANY ACCUMULATION SHOULD BE A DUSTING.
ON WEDNESDAY...THE NOCTURNAL SNOW SHOWERS WILL MOVE OUT OF THE AREA
DURING THE MORNING. THERE MAY OR MAY NOT BE A LULL IN ACTIVITY IN
THE LATE MORNING. ACCUMULATIONS WEDNESDAY MORNING SHOULD AGAIN BE A
DUSTING AT BEST.
NEW DIURNAL SNOW SHOWERS WILL DEVELOP WEDNESDAY AFTERNOON WITH THE
BETTER CHANCES EAST OF THE MISSISSIPPI. THE BEST CHANCES FOR SNOW
SHOWERS ACTUALLY LOOK TO BE EAST OF I-39. THE QUESTION WEDNESDAY
AFTERNOON IS WILL THERE BE ANY NEW ACCUMULATION. AT BEST THERE MAY
BE A DUSTING ON THE GRASS OR ELEVATED SURFACES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 315 PM CST TUE DEC 1 2015
MAIN FORECAST CONCERN FOR THE LONG TERM ARE THE ABOVE NORMAL
TEMPERATURES FORECAST THROUGH THE PERIOD AND A CHANCE FOR
PRECIPITATION AT THE END OF THE PERIOD. AT THIS TIME IT LOOKS LIKE
THERE IS A LOW CHANCE FOR PRECIP AND A GOOD CHANCE FOR TEMPERATURES
TO REACH NEAR 50 THIS WEEKEND.
LARGE SCALE RIDGING WILL TURN TO SW FLOW LATE DURING THE WEEK.
MODERATION UNDER THIS RIDGE ALONG WITH THE SW FLOW WILL LEAD TO WELL
ABOVE NORMAL TEMPERATURES. HIGHS ON SATURDAY COULD BE AS HIGH AS 10
DEGREES ABOVE NORMAL ACROSS MOST OF THE AREA. LITTLE TO NO SENSIBLE
WEATHER IS EXPECTED DURING THIS TIME WITH THE EXCEPTION OF SOME
CLOUDS ASSOCIATED WITH A MID LEVEL WAVE MID WEEK.
MID WEEKEND AN ADVANCING MID LEVEL WAVE AND TRAILING COLD FRONT ARE
FORECAST TO SWEEP THROUGH THE AREA. MODELS ARE IN GOOD AGREEMENT
WITH THE LARGE SCALE PATTERN AND FLOW. HOWEVER...THE MESOSCALE
FEATURES ASSOCIATED WITH THE COLD FRONT ARE LEADING TO LIMITED
FORECASTABILITY FOR ANY PRECIP ALONG THE FRONT. AT THIS TIME...THE
BEST CHANCES FOR PRECIP LOOK TO BE ACROSS SOUTHERN ZONES. THIS WILL
LIKELY CHANGE AS WE APPROACH THE WEEKEND. REGARDLESS...MOST OF THE
LONG TERM FORECAST LOOKS TO BRING WARMER TEMPERATURES AND QUIET
WEATHER TO THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1120 PM CST TUE DEC 1 2015
MOSTLY VFR CONDITIONS THE NEXT 24 HOURS. THE REGION TO REMAIN UNDER
CYCLONIC FLOW RESULTING IN LOTS OF CLOUDS WITH SCATTERED FLURRIES AND
SNOW SHOWERS...MOSTLY BETWEEN 02/08Z AND 02/16Z. THE HEAVIEST SNOW
SHOWERS MAY LOWER VISIBILITIES TO 2 MILES OR LESS FOR SHORT PERIODS
OF TIME WITH BASES DOWN TO 1-2K AGL. OTHERWISE...VISIBILITIES TO BE
6 PLUS MILES WITH CEILING AOA 3K AGL.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...GIBBS
AVIATION...NICHOLS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1052 PM EST THU DEC 3 2015
.UPDATE...
ISSUED AT 1050 PM EST THU DEC 3 2015
HIGH PRESSURE CONTINUES AT THE SFC AND ALOFT CONTINUES TO BUILD
INTO EASTERN KY. THE PESKY STRATOCU HAS MOVED OUT OF THE CWA WITH
THE BACK EDGE IN THE KY/WV/OH TRI STATE AREA. MEANWHILE...LOW
CLOUDS OVER IL IS MAKING LITTLE IF ANY SOUTHEAST PROGRESS AND IS
NOT EXPECTED TO EXPAND AS HEIGHTS RISE. DEWPOINT DEPRESSIONS AT
KY MESONET SITES AND CWOP OR DAVIS STATION SITES ARE SMALL SO
VALLEY FOG MAY ALREADY HAVE DEVELOPED IN SOME AREAS OR COULD
DEVELOP IN THE NEXT FEW HOURS EVEN IF IT IS SHORT LIVED AND
DISSIPATES AS FROST DEVELOPS PRIOR TO DAWN.
UPDATE ISSUED AT 710 PM EST THU DEC 3 2015
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS
AND SATELLITE AND SHORT TERM MODEL TRENDS. THIS LED TO A BIT MORE
SKY COVER ACROSS THE NORTH AND NORTHEAST PART OF THE CWA DURING
THE NEXT FEW HOURS AS THE STRATOCU SHOULD FINALLY MOVE EAST AS A
SHORTWAVE DEPARTS TO THE EAST AND NORTHEAST. THE HOURLY
TEMPERATURE CURVE WILL BE THE MAIN FORECAST CHALLENGE FOR TONIGHT
AND THE POSSIBILITY OF VALLEY FOG OF VALLEY FOG THAT DEVELOPS
EARLY IN THE NIGHT AND POSSIBLY DISSIPATES AS FROST FORMS.
ATTM...PATCHY RIVER VALLEY FOG HAS BEEN ADDED TO THE GRIDS.
OTHERWISE...NO SIGNIFICANT CHANGES WERE NEEDED AT THIS TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 326 PM EST THU DEC 3 2015
HIGH PRESSURE CONTINUES TO NOSE INTO THE REGION THIS AFTERNOON AS
LOW PRESSURE THAT BROUGHT PRECIP RESIDES NEAR THE MAINE COAST.
SOME PESKY STRATUS ON THE BACK END OF THE SYSTEM HAS BEEN THE
BIGGEST IMPACT TODAY...BUT MOST AREAS HAVE ENJOYED MOSTLY SUNNY
SKIES THIS AFTERNOON WITH FAR NORTH SEEING A BIT MORE IN THE WAY
OF CLOUDS. THIS AREA OF SURFACE HIGH PRESSURE WILL CONTINUE TO
BUILD AND CREST ACROSS THE REGION TONIGHT INTO FRIDAY. THIS WILL
USHER IN DRY CONDITIONS INTO THE REGION THROUGH THE SHORT TERM
PERIOD. LOW TEMPS THROUGH THE PERIOD WILL DROP INTO THE UPPER 20S
TO LOWER 30S ON RIDGES AND LOW TO MID 20S FOR OVERNIGHT. TONIGHT
WILL BE THE MORE TRICKY LOW TEMP FORECAST DEPENDING ON HOW MUCH
THE STRATUS DECK HOLD ON. THE TEMPS DO REBOUND TOMORROW WITH
HIGHS GETTING BACK INTO THE UPPER 40S TO LOWER 50S...THAT SAID THE
AIRMASS DOES DRY OUT AND WILL LEAD TO LOWERING RH VALUES IN THE
AFTERNOON. RIGHT NOW STICKING WITH MID TO UPPER 30 VALUES GIVEN
THE RECENT RAINS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 326 PM EST THU DEC 3 2015
HIGH PRESSURE WILL HOLD ITS GROUND THROUGH SUNDAY...WITH HIGHS
REMAINING ABOVE GUIDANCE GENERALLY AROUND 60...AND LOWS BELOW
GUIDANCE INTO THE 20S.
HIGH PRESSURE WILL RETREAT TO THE EAST SUNDAY NIGHT AS A SHORTWAVE
TROUGH CROSSES THE OHIO RIVER VALLEY. MODELS STILL NOT IN TOTAL
AGREEMENT ON THE TIMING OF THIS SYSTEM...BUT GIVEN THE PROGRESSIVE
NATURE OF THE SYSTEM...THE ECMWF MAY HAVE A SLIGHTLY BETTER HANDLE
ON THIS SYSTEM. THUS...WILL BRING IN SOME RAIN CHANCES SUNDAY NIGHT
THROUGH MONDAY...BEFORE WE DRY OUT AGAIN AS WE HEAD THROUGH MONDAY
NIGHT AND TUESDAY. WET WEATHER COULD RETURN BY MIDDLE OF THE
WEEK...BUT GIVEN THE SHORTER TERM MODEL DISAGREEMENT...NOT WILLING
TO JUMP ON THIS WETTER PERIOD YET.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 723 PM EST THU DEC 3 2015
HIGH PRESSURE WILL CONTINUE TO NOSE INTO THE REGION THROUGH THE
TAF PERIOD LEADING THE MOSTLY VFR CONDITIONS. SOME PESKY STRATOCU
LINGERS NEAR IOB AND SYM AS WELL AS NORTHEAST KY BUT THESE SHOULD
DISSIPATE OR MOVE TO THE EAST AND NORTHEAST DURING THE FIRST 3 TO
5 HOUR OF THE PERIOD. SOME OF THE STRATOCU MAY ALSO PASS NEAR JKL
AND SJS. MVFR CIGS WERE KEPT IN PLACE AT SYM UNTIL 2Z...WITH SCT
CLOUDS BELOW 3KFT AT JKL AND SJS THROUGH 3Z OR 4Z.
OTHERWISE...RIVER VALLEY FOG POSSIBLY REDUCING VIS TO IFR OR LOWER
MAY DEVELOP BY 3Z AND 4Z AND POSSIBLY LINGERING THROUGH 14Z OR
DISSIPATING AS FROST FORMS. THIS FOG IF IT DEVELOPS COULD LIFT
INTO SJS AND SYM AND BRING SOME MVFR OR POSSIBLY IFR VIS 8Z TO 14Z
AND WAS INCLUDED IN THE TAF. OTHERWISE VFR CONDITIONS WITH LIGHT
WINDS WILL PREVAILS AS HIGH PRESSURE MOVES IN.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...DJ
LONG TERM...KAS
AVIATION...JP
[top]
Area Forecast Discussion
National Weather Service Louisville KY
1036 PM EST THU DEC 3 2015
...Forecast Update...
Issued at 1036 PM EST Thu Dec 3 2015
HRRR and RAP have been consistent this evening advertising fog
forming over southern Indiana tonight. As early as 10pm EST fog had
indeed already begun to form from southern Illinois through south
central Indiana to the southwest corner of Ohio. So, went ahead and
added patchy fog to our southern Indiana counties. Also put in some
fog in parts of the Kentucky and Licking River valleys where fog
forms easily on calm, clear nights.
.SHORT TERM (Now through Friday Night)...
Issued at 250 PM EST Thu Dec 3 2015
High pressure centered just to our west this afternoon will shift
slowly eastward to our longitude Friday morning and will keep winds
light and variable overnight...meaning another cool morning, but not
too far below normal for this time of year. Temperatures may be
moderated over our north a bit by some low clouds forecast to drift
in here from the north. Forecast soundings show that air mixing with
the drier air aloft to thin out those clouds by daybreak Friday.
Otherwise, expect a nice day Friday and then another cool night as
the high only gets into the upper Ohio River Valley by daybreak
Saturday. We should get to a few degrees warmer for morning lows
then, as we`ll start off with warmer temperatures for highs Friday
compared to today.
.LONG TERM (Saturday through Thursday)...
Issued at 250 PM EST Thu Dec 3 2015
We should have another nice day Saturday, with warming temperatures
again. Sunday may be cooler though as thicknesses start to drop
ahead of an upper level system approaching from the Plains. Upper
clouds will stream in here as the flow aloft taps into some Gulf
moisture. Surface winds will be from the south which should offset
the cooling caused by these clouds. Expect readings still to be
above normal though for highs.
GFS is continuing to hold on to its slower solution for an upper low
travelling in from the Central Plains Sunday and Sunday night. The
European and GEM are nearly in sync with a faster solution, given
that it places the low farther north and closer to the mean westerly
flow. The GEFS spreads at 500mb focus on southwest MO but have
higher spreads up into Michigan, indicating a leaning towards this
solution as well. Thus will focus our best rain chances for Sunday
night and make Monday mostly dry, against what the GFS advertises,
with a lingering rain chance in our far south and east counties.
Next up is yet another upper low dropping in from the Plains.
Blended forecast went dry for that period, but given how well the
Euro guidance has been doing the past few months decided to go with
at least slight chance pops. Later forecasts can continue the trend
up if need be.
&&
.AVIATION (00Z TAF Update)...
Updated at 604 PM EST Thu Dec 3 2015
High pressure overhead throughout the TAF period will keep our
weather quiet. There is a question of some patchy fog in southern
Indiana and the Kentucky Blue Grass early Friday morning. At this
time it appears that urban SDF will remain clear. At LEX
temperatures are expected to fall to right around their cross-over
temperature, but dew point depressions look large enough that we can
keep the TAF clear for now.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........13
Short Term.....RJS
Long Term......RJS
Aviation.......13
AREA FORECAST DISCUSSION
National Weather Service Paducah KY
231 PM CST WED DEC 2 2015
.SHORT TERM...(This evening through Friday night)
Issued at 214 PM CST WED DEC 2 2015
It appears the GFS is/has been modeling the low layer cloud
field/embedded pcpn pertaining to the wrap around spiral bands
rotating south of the Low track today. A close examination of the
GFS20 vs the NAM12 Modeled Sounding data reveals this in better
detail, and the net effect will be a sliver of isolated pops for
our northern most tier of counties/partial counties for snow
showers this evening/early night. Amounts should be miniscule and
melt upon grounding.
After tonight, dry/cold air advection more firmly overtakes the
entire atmospheric column, as surface High pressure anchors across
the Commonwealth. This will lead to 40s tmrw, again
Friday/approaching 50, with mainly upper half 20s/nr 30 each
night through the remainder of the work week.
.LONG TERM...(Saturday through Wednesday)
Issued at 214 PM CST WED DEC 2 2015
At the beginning of the extended period, high pressure at the sfc
and aloft over the PAH forecast area will begin to give way to srly
low level flow ahead of a developing mid level shrtwv trof.
The forward speed and evolution of the trof continues to be in
question by the med range models as it is shown to dive into the
central Plains midway through the weekend. Some model solutions
suggest an fast open wave (UKMET) and some favor a slower closed
low. The deterministic 12Z GFS had an especially srly, slow, and
deep solution, which affected the initialization blend all the way
into Tue. The GFS ensemble means even had a closed low in the data
by early Mon. WPC appeared to gravitate toward a faster, ensemble-
mean-dominated trend. Sfc reflection is limited, and it is an
educated guess as to what the sfc wind fields will look like from
Sun through Tue.
For this forecast package, due to timing/coverage uncertainty in the
pcpn fields, we will go with no more than slight chances of rain
showers for most of the region Sun through Mon, with just a sliver
of PoP remaining in the srn Pennyrile Mon night. This was only a
modest deviation from the initialization blend, in fact. Dry weather
is forecast beyond Mon night, with not a whole lot of change in the
near-seasonable temps with time.
&&
.AVIATION...
Issued at 214 PM CST WED DEC 2 2015
Model Soundings reveal sharp lapse rates in the boundary layer, up
to about 4-5K FT AGL, and this has helped bouy moistened parcels
into scattered low VFR decks with occasional bkn-ovc cigs this
pm. More extensive cyclone induced wrap around MVFR cigs will
threaten overnight, with the potential for a brief period of light
frozen pcpn restricting vsbys to MVFR at KEVV/KOWB. W-NW flow
will continue with occasional diurnal gustiness.
&&
.PAH Watches/Warnings/Advisories...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
Area Forecast Discussion
National Weather Service Louisville KY
300 PM EST WED DEC 2 2015
.SHORT TERM (Now through Thursday Night)...
Issued at 300 PM EST Wed Dec 2 2015
Main forecast concern this period is precip type with showers
expected ahead of an upper low now dropping south-southeast across
northern Illinois. The center of this feature will be over the
central IL/IN border by 00Z, and model soundings continue to show
our north and northeast zones saturated just up to the dendritic
growth zone, especially the latest NAM. The GFS and RUC are not as
robust, but given possibility and the axis of coldest temperatures
aloft swinging through at that point have kept in the snow or rain
shower chances through the evening hours. Given breezy conditions,
would not be surprised to see some briefly lower vsby in any heavier
snow showers across our northeast.
High pressure will build in slowly from the west for Thursday and
Thursday night, making for temperatures a little below
normal...though skies will be sunnier compared to the last few days.
.LONG TERM (Friday through Wednesday)...
Issued at 300 PM EST Wed Dec 2 2015
High pressure will be over us Friday and then just to our east
Saturday. For Sunday and upper low moves across the Central Plains.
Forecast models, not surprisingly, differ in timing of this low
moving towards our region, with the 00Z Euro and the latest GEM
showing it right over our longitude by Monday morning, whereas the
GFS slows the low down and moves it into Deep South. The first camp
would bring precip in here Sunday night, whereas the latter holds it
off until Monday night. The 00Z GEFS has a high spread toward the
Euro and GEM solution, so have to keep in some pops Sunday night.
After that system, and assuming the Euro/GEM solution is the correct
choice, the next system drops into the Central Plains Wednesday.
There should be enough distance between these two systems to
preclude precip chances advertised by the GFS (which given it`s
slower solution has the two phasing a little and keeping enough
moisture around to generater rain chances). Will go dry for
Wednesday.
&&
.AVIATION (18Z TAF Update)...
Updated at 1222 PM EST Wed Dec 2 2015
A secondary cold front is sweeping through the TAF sites at this
hour ahead of a potent upper disturbance. Expect generally W surface
winds between 10 and 20 mph, with gusts up around 30 mph at times. A
few light sprinkles may accompany this frontal passage, but coverage
intensity are too light to cause any impacts.
Another frontal passage occurs later this evening ahead of another
upper disturbance. Won`t be much of a wind shift with this feature,
but gusty winds will continue. Additionally, some sprinkles/light
showers may transition to flurries/light snow showers during this
time. Will mention VCSH at SDF/LEX, but impacts should be pretty
low.
Ceilings are a little tricky given the mixy low levels, but have
stayed optimistic with Sct-Bkn high end MVFR/low VFR range. BWG
should stay just above MVFR/VFR threshold. Skies clear out after
Midnight from W to E, with light WNW winds and clear skies
prevailing.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Short Term........RJS
Long Term.........RJS
Aviation..........BJS
AREA FORECAST DISCUSSION
NWS JACKSON KY
308 AM EST WED DEC 2 2015
.UPDATE...
ISSUED AT 129 AM EST WED DEC 2 2015
FRESHENED UP THE POPS OVER THE NEXT FEW HOURS. ENHANCED ECHOES
HAVE BEEN MOVING ACROSS SOUTHEASTERN KENTUCKY OVER THE PAST FEW
HOURS...AS AN UPPER LEVEL JET STREAK LENDS INFLUENCE. THE 00Z
MODELS SEEM TO BE A BIT OVERDONE WITH THE AMOUNT OF QPF PREDICTED
TO FALL THROUGH 09Z...HOWEVER THERE HAVE BEEN POCKETS OF HIGHER
RAINFALL RATES OF UP TO 0.3 INCHES PER HOUR AT TIMES. GIVEN THESE
HIGHER RAINFALL RATES...HAVE ISSUED A FLOOD ADVISORY FOR QUITE A
BIT OF THE SOUTHEAST...WHERE THE HEAVIEST RAINFALL TOTALS HAVE
BEEN OVER THE PAST FEW DAYS. EXPECT AT LEAST LIGHT TO MODERATE
SHOWERS TO CONTINUE ACROSS MUCH OF THE AREA THROUGH 09Z...BEFORE
THE FORCING RELAXES. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT
1108 PM EST TUE DEC 1 2015
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS.
NEW 0Z MODEL GUIDANCE AND RECENT SHORT TERM GUIDANCE SUCH AS THE
HRRR CONTINUED TO SUPPORT THE CURRENT POPS...SO NO CHANGES WERE
MADE TO THESE ATTM.
UPDATE ISSUED AT 735 PM EST TUE DEC 1 2015
A COLD FRONT HAS REACHED THE VA BORDER COUNTIES...BUT PRECIPITATION
LINGERS IN ITS VICINITY. ON ADDITIONAL SFC WAVE IS EXPECTED TO
LIFT NORTHEAST THROUGH EARLY ON TUESDAY AND THIS WILL BRING
CONTINUED CHANCES FOR SHOWERS ESPECIALLY ACROSS THE CENTRAL AND
SOUTHEAST CWA. LOCATIONS ACROSS THE BLUEGRASS REGION WILL LIKELY
REMAIN DRY. BASED ON RECENT RADAR TRENDS AND SHORT TERM MODEL
GUIDANCE HAS OPTED TO INCREASE CHANCES FOR MEASURABLE RAIN ACROSS
THE CENTRAL AND SOUTHEAST CWA DURING THE FIRST 6 TO 8 HOURS OF THE
PERIOD AS WELL AS SKY COVER. RECENT HRRR AND OTHER MODEL RUNS WERE
A TAD HIGHER WITH QPF ACROSS THIS AREA AS WELL...SO QPF ACROSS THE
CENTRAL AND EAST WAS INCREASE A TENTH OR SO. OTHERWISE...HOURLY
TRENDS WERE FRESHENED UP BASED ON RECENT OBSERVATIONS...BUT THIS
LED TO NO SUBSTANTIAL CHANGE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 355 PM EST TUE DEC 1 2015
20Z SFC ANALYSIS SHOWS A COLD FRONT SETTLING OVER FAR EASTERN
KENTUCKY WITH SHOWERS AFFECTING THE CWA BOTH ALONG AND BEHIND THIS
BOUNDARY. TEMPERATURES VARY WITH THE FRONTAL POSITION AS COOLER
AIR IS POURING IN ON WEST WINDS FOR WESTERN PARTS OF THE AREA
WHILE WARMTH REMAINS IN THE FAR EAST. SPECIFICALLY...TEMPERATURES
VARY FROM THE LOWER 50S IN THE WEST TO THE LOWER 60S NEAR THE
VIRGINIA BORDER. DEWPOINTS LIKEWISE VARY WITH THE TEMPERATURE
WITHIN A DEGREE OR TWO OF THE DRY BULB VALUES. WINDS ARE FROM THE
SOUTH TO SOUTHWEST FOR THE EASTERN PARTS OF THE CWA WHILE THEY ARE
MORE WESTERLY TO THE WEST RUNNING AT 5 TO 10 MPH WITH OCCASIONAL
GUSTS TO 15 OR 20 MPH.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS
THEY ALL TAKE A FAIRLY DEEP...AND COMPACT...LOW THROUGH THE UPPER
MIDWEST AND INTO THE GREAT LAKES DURING THE PERIOD. THE CORE OF
THIS LOWS ENERGY DOES TARGET THE LOWER PARTS OF THE OHIO VALLEY
AS IT MOVES BY LATER WEDNESDAY. GIVEN THE MODEL AGREEMENT HAVE
FAVORED THE HIGHER RESOLUTION GUIDANCE FROM THE NAM12 AND HRRR
THROUGH THE SHORT TERM PORTION OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE SHOWERS CONTINUING TO AFFECT THE FAR
EASTERN PART OF THE AREA ALONG THAT STALLED FRONT. TO THE WEST
LIGHT SHOWERS AND SPRINKLES WILL BE FOUND. THE DRIER AIR MOVES
INTO THE WESTERN PARTS OF EASTERN KENTUCKY TONIGHT INTO WEDNESDAY
ENDING ANY ACCUMULATING RAINS...THOUGH FOG AND LOW CLOUDS WILL
REMAIN INTO THE MORNING. HOWEVER...HAVE ISSUED A FLOOD ADVISORY
FOR QUITE A BIT OF THE SOUTHEAST...WHERE THE HEAVIEST RAINFALL
TOTALS HAVE BEEN OVER THE PAST FEW DAYS. EAST THE SHOWERS WILL
LINGER WELL INTO THE DAY WEDNESDAY. ADDITIONALLY...A SECONDARY
COLD FRONT WILL MOVE INTO THE AREA ON WEDNESDAY EVENING AND
OVERNIGHT BRINGING A POTENTIAL FOR SPRINKLES OR FLURRIES TO AT
LEAST NORTHERN PARTS OF THE AREA. THE AIR WILL DRY OUT THROUGHOUT
THE STATE BY DAWN THURSDAY. COLDER AIR WILL GRADUALLY FILTER INTO
THE AREA THROUGH WEDNESDAY WITH A BIGGER SURGE THAT NIGHT FOR LOWS
BACK TO NEAR FREEZING BY DAWN THURSDAY.
USED THE SHORTBLEND AS A STARTING POINT FOR THE T AND TD GRIDS
INTO WEDNESDAY MORNING AND THE SUPERBLEND THEREAFTER. FROM THIS
MADE SOME MINOR...TERRAIN BASED...ADJUSTMENTS TO THE LOW
TEMPERATURES TONIGHT AND WEDNESDAY NIGHT. AS FOR POPS ENDED UP
SIMILAR TO MOS BLEND FOR TONIGHT AND WEDNESDAY THE ON THE HIGH
SIDE BY A TAD FOR WEDNESDAY NIGHT.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 310 AM EST WED DEC 2 2015
AN EXTENDED STRETCH OF DRY WEATHER IS EXPECTED FOR THE MAJORITY OF
THE EXTENDED PERIOD AS A RIDGE BUILDS IN OVERHEAD BY THURSDAY NIGHT
AND REMAINS NEARLY STATIONARY THROUGH THE UPCOMING WEEKEND. WITH LOW
PW/S AROUND 0.15 THROUGH THE WEEKEND...WE WILL LIKELY SEE SOME LARGE
DIURNAL RANGES EACH DAY WITH COLD MORNINGS AND MILD AFTERNOONS WITH
HIGHS LIKELY REACHING ABOVE MODEL GUIDANCE EACH DAY AND POSSIBLY
UNDER GUIDANCE AT NIGHT. THE NEXT CHANCE OF RAIN MAY COME SOMETIME
ON MONDAY WHEN AN UPPER LEVEL LOW SWINGS THROUGH OUR AREA.
THOUGH...MODEL SOLUTIONS DIVERGE HERE...SO STUCK CLOSE TO CR
SUPERBLEND FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 129 AM EST WED DEC 2 2015
MVFR/IFR CONDITIONS WILL HANG ON THROUGH THE MID-MORNING HOURS ON
WEDNESDAY AS A COLD FRONT SLOWLY EXITS OFF TO THE SOUTHEAST. THE
MORE SUSTAINED SHOWERS WILL OCCUR ALONG A LINE FROM SJS TO JKL TO
SME THROUGH 09Z...BEFORE GRADUALLY TAPERING OFF FROM NORTHWEST TO
SOUTHEAST THROUGH 12Z. CEILINGS WILL RAISE UP TO VFR THROUGH
AROUND NOON. AN APPROACHING UPPER LEVEL DISTURBANCE WILL THEN
BRING IN LOWER CEILINGS FROM THE NORTHWEST TOWARDS THE END OF THE
PERIOD. WINDS WILL REMAIN AT AROUND 5 KTS OR LESS THROUGH
WEDNESDAY MORNING. WINDS WILL THEN INCREASE TO AROUND 10
KTS OUT OF THE WEST SOUTHWEST...WITH SOME GUSTS UP TO 15 KTS AT
TIMES DURING THE AFTERNOON...BEFORE DIMINISHING TOWARDS DUSK.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...GREIF
LONG TERM...JVM/KAS
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
130 AM EST WED DEC 2 2015
.UPDATE...
ISSUED AT 129 AM EST WED DEC 2 2015
FRESHENED UP THE POPS OVER THE NEXT FEW HOURS. ENHANCED ECHOES
HAVE BEEN MOVING ACROSS SOUTHEASTERN KENTUCKY OVER THE PAST FEW
HOURS...AS AN UPPER LEVEL JET STREAK LENDS INFLUENCE. THE 00Z
MODELS SEEM TO BE A BIT OVERDONE WITH THE AMOUNT OF QPF PREDICTED
TO FALL THROUGH 09Z...HOWEVER THERE HAVE BEEN POCKETS OF HIGHER
RAINFALL RATES OF UP TO 0.3 INCHES PER HOUR AT TIMES. GIVEN THESE
HIGHER RAINFALL RATES...HAVE ISSUED A FLOOD ADVISORY FOR QUITE A
BIT OF THE SOUTHEAST...WHERE THE HEAVIEST RAINFALL TOTALS HAVE
BEEN OVER THE PAST FEW DAYS. EXPECT AT LEAST LIGHT TO MODERATE
SHOWERS TO CONTINUE ACROSS MUCH OF THE AREA THROUGH 09Z...BEFORE
THE FORCING RELAXES. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT
1108 PM EST TUE DEC 1 2015
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS.
NEW 0Z MODEL GUIDANCE AND RECENT SHORT TERM GUIDANCE SUCH AS THE
HRRR CONTINUED TO SUPPORT THE CURRENT POPS...SO NO CHANGES WERE
MADE TO THESE ATTM.
UPDATE ISSUED AT 735 PM EST TUE DEC 1 2015
A COLD FRONT HAS REACHED THE VA BORDER COUNTIES...BUT PRECIPITATION
LINGERS IN ITS VICINITY. ON ADDITIONAL SFC WAVE IS EXPECTED TO
LIFT NORTHEAST THROUGH EARLY ON TUESDAY AND THIS WILL BRING
CONTINUED CHANCES FOR SHOWERS ESPECIALLY ACROSS THE CENTRAL AND
SOUTHEAST CWA. LOCATIONS ACROSS THE BLUEGRASS REGION WILL LIKELY
REMAIN DRY. BASED ON RECENT RADAR TRENDS AND SHORT TERM MODEL
GUIDANCE HAS OPTED TO INCREASE CHANCES FOR MEASURABLE RAIN ACROSS
THE CENTRAL AND SOUTHEAST CWA DURING THE FIRST 6 TO 8 HOURS OF THE
PERIOD AS WELL AS SKY COVER. RECENT HRRR AND OTHER MODEL RUNS WERE
A TAD HIGHER WITH QPF ACROSS THIS AREA AS WELL...SO QPF ACROSS THE
CENTRAL AND EAST WAS INCREASE A TENTH OR SO. OTHERWISE...HOURLY
TRENDS WERE FRESHENED UP BASED ON RECENT OBSERVATIONS...BUT THIS
LED TO NO SUBSTANTIAL CHANGE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 355 PM EST TUE DEC 1 2015
20Z SFC ANALYSIS SHOWS A COLD FRONT SETTLING OVER FAR EASTERN
KENTUCKY WITH SHOWERS AFFECTING THE CWA BOTH ALONG AND BEHIND THIS
BOUNDARY. TEMPERATURES VARY WITH THE FRONTAL POSITION AS COOLER
AIR IS POURING IN ON WEST WINDS FOR WESTERN PARTS OF THE AREA
WHILE WARMTH REMAINS IN THE FAR EAST. SPECIFICALLY...TEMPERATURES
VARY FROM THE LOWER 50S IN THE WEST TO THE LOWER 60S NEAR THE
VIRGINIA BORDER. DEWPOINTS LIKEWISE VARY WITH THE TEMPERATURE
WITHIN A DEGREE OR TWO OF THE DRY BULB VALUES. WINDS ARE FROM THE
SOUTH TO SOUTHWEST FOR THE EASTERN PARTS OF THE CWA WHILE THEY ARE
MORE WESTERLY TO THE WEST RUNNING AT 5 TO 10 MPH WITH OCCASIONAL
GUSTS TO 15 OR 20 MPH.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS
THEY ALL TAKE A FAIRLY DEEP...AND COMPACT...LOW THROUGH THE UPPER
MIDWEST AND INTO THE GREAT LAKES DURING THE PERIOD. THE CORE OF
THIS LOWS ENERGY DOES TARGET THE LOWER PARTS OF THE OHIO VALLEY
AS IT MOVES BY LATER WEDNESDAY. GIVEN THE MODEL AGREEMENT HAVE
FAVORED THE HIGHER RESOLUTION GUIDANCE FROM THE NAM12 AND HRRR
THROUGH THE SHORT TERM PORTION OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE SHOWERS CONTINUING TO AFFECT THE FAR
EASTERN PART OF THE AREA ALONG THAT STALLED FRONT. TO THE WEST
LIGHT SHOWERS AND SPRINKLES WILL BE FOUND. THE DRIER AIR MOVES
INTO THE WESTERN PARTS OF EASTERN KENTUCKY TONIGHT INTO WEDNESDAY
ENDING ANY ACCUMULATING RAINS...THOUGH FOG AND LOW CLOUDS WILL
REMAIN INTO THE MORNING. HOWEVER...TO THEHAVE ISSUED A FLOOD ADVISORY FOR QUITE A BIT OF
THE SOUTHEAST...WHERE THE HEAVIEST RAINFALL TOTALS HAVE BEEN OVER
THE PAST FEW DAYS. EAST THE SHOWERS WILL LINGER WELL INTO THE
DAY WEDNESDAY. ADDITIONALLY...A SECONDARY COLD FRONT WILL MOVE
INTO THE AREA ON WEDNESDAY EVENING AND OVERNIGHT BRINGING A
POTENTIAL FOR SPRINKLES OR FLURRIES TO AT LEAST NORTHERN PARTS OF
THE AREA. THE AIR WILL DRY OUT THROUGHOUT THE STATE BY DAWN
THURSDAY. COLDER AIR WILL GRADUALLY FILTER INTO THE AREA THROUGH
WEDNESDAY WITH A BIGGER SURGE THAT NIGHT FOR LOWS BACK TO NEAR
FREEZING BY DAWN THURSDAY.
USED THE SHORTBLEND AS A STARTING POINT FOR THE T AND TD GRIDS
INTO WEDNESDAY MORNING AND THE SUPERBLEND THEREAFTER. FROM THIS
MADE SOME MINOR...TERRAIN BASED...ADJUSTMENTS TO THE LOW
TEMPERATURES TONIGHT AND WEDNESDAY NIGHT. AS FOR POPS ENDED UP
SIMILAR TO MOS BLEND FOR TONIGHT AND WEDNESDAY THE ON THE HIGH
SIDE BY A TAD FOR WEDNESDAY NIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 215 PM EST TUE DEC 1 2015
AN EXTENDED STRETCH OF DRY WEATHER IS EXPECTED FOR THE ENTIRE
EXTENDED PERIOD AS A RIDGE BUILDS IN OVERHEAD AND REMAINS NEARLY
STATIONARY THROUGH THE UPCOMING WEEKEND. WITH PW`S AROUND 0.15
THROUGH THE WEEKEND...WE WILL LIKELY SEE SOME LARGE DIURNAL RANGES
EACH DAY WITH COLD MORNINGS AND MILD AFTERNOONS WITH HIGHS LIKELY
REACHING ABOVE MODEL GUIDANCE EACH DAY AND POSSIBLY UNDER GUIDANCE
AT NIGHT. NEXT CHANCE OF RAIN MAY COME SOMETIME AROUND NEXT
TUESDAY...ALTHOUGH GIVEN THE PATTERN GOING INTO TUESDAY...NOT
WILLING TO BITE ON THIS SYSTEM YET.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 129 AM EST WED DEC 2 2015
MVFR/IFR CONDITIONS WILL HANG ON THROUGH THE MID-MORNING HOURS ON
WEDNESDAY AS A COLD FRONT SLOWLY EXITS OFF TO THE SOUTHEAST. THE
MORE SUSTAINED SHOWERS WILL OCCUR ALONG A LINE FROM SJS TO JKL TO
SME THROUGH 09Z...BEFORE GRADUALLY TAPERING OFF FROM NORTHWEST TO
SOUTHEAST THROUGH 12Z. CEILINGS WILL RAISE UP TO VFR THROUGH
AROUND NOON. AN APPROACHING UPPER LEVEL DISTURBANCE WILL THEN
BRING IN LOWER CEILINGS FROM THE NORTHWEST TOWARDS THE END OF THE
PERIOD. WINDS WILL REMAIN AT AROUND 5 KTS OR LESS THROUGH
WEDNESDAY MORNING. WINDS WILL THEN INCREASE TO AROUND 10
KTS OUT OF THE WEST SOUTHWEST...WITH SOME GUSTS UP TO 15 KTS AT
TIMES DURING THE AFTERNOON...BEFORE DIMINISHING TOWARDS DUSK.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1108 PM EST TUE DEC 1 2015
.UPDATE...
ISSUED AT 1108 PM EST TUE DEC 1 2015
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS.
NEW 0Z MODEL GUIDANCE AND RECENT SHORT TERM GUIDANCE SUCH AS THE
HRRR CONTINUED TO SUPPORT THE CURRENT POPS...SO NO CHANGES WERE
MADE TO THESE ATTM.
UPDATE ISSUED AT 735 PM EST TUE DEC 1 2015
A COLD FRONT HAS REACHED THE VA BORDER COUNTIES...BUT PRECIPITATION
LINGERS IN ITS VICINITY. ON ADDITIONAL SFC WAVE IS EXPECTED TO
LIFT NORTHEAST THROUGH EARLY ON TUESDAY AND THIS WILL BRING
CONTINUED CHANCES FOR SHOWERS ESPECIALLY ACROSS THE CENTRAL AND
SOUTHEAST CWA. LOCATIONS ACROSS THE BLUEGRASS REGION WILL LIKELY
REMAIN DRY. BASED ON RECENT RADAR TRENDS AND SHORT TERM MODEL
GUIDANCE HAS OPTED TO INCREASE CHANCES FOR MEASURABLE RAIN ACROSS
THE CENTRAL AND SOUTHEAST CWA DURING THE FIRST 6 TO 8 HOURS OF THE
PERIOD AS WELL AS SKY COVER. RECENT HRRR AND OTHER MODEL RUNS WERE
A TAD HIGHER WITH QPF ACROSS THIS AREA AS WELL...SO QPF ACROSS THE
CENTRAL AND EAST WAS INCREASE A TENTH OR SO. OTHERWISE...HOURLY
TRENDS WERE FRESHENED UP BASED ON RECENT OBSERVATIONS...BUT THIS
LED TO NO SUBSTANTIAL CHANGE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 355 PM EST TUE DEC 1 2015
20Z SFC ANALYSIS SHOWS A COLD FRONT SETTLING OVER FAR EASTERN
KENTUCKY WITH SHOWERS AFFECTING THE CWA BOTH ALONG AND BEHIND THIS
BOUNDARY. TEMPERATURES VARY WITH THE FRONTAL POSITION AS COOLER
AIR IS POURING IN ON WEST WINDS FOR WESTERN PARTS OF THE AREA
WHILE WARMTH REMAINS IN THE FAR EAST. SPECIFICALLY...TEMPERATURES
VARY FROM THE LOWER 50S IN THE WEST TO THE LOWER 60S NEAR THE
VIRGINIA BORDER. DEWPOINTS LIKEWISE VARY WITH THE TEMPERATURE
WITHIN A DEGREE OR TWO OF THE DRY BULB VALUES. WINDS ARE FROM THE
SOUTH TO SOUTHWEST FOR THE EASTERN PARTS OF THE CWA WHILE THEY ARE
MORE WESTERLY TO THE WEST RUNNING AT 5 TO 10 MPH WITH OCCASIONAL
GUSTS TO 15 OR 20 MPH.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM AS
THEY ALL TAKE A FAIRLY DEEP...AND COMPACT...LOW THROUGH THE UPPER
MIDWEST AND INTO THE GREAT LAKES DURING THE PERIOD. THE CORE OF
THIS LOWS ENERGY DOES TARGET THE LOWER PARTS OF THE OHIO VALLEY
AS IT MOVES BY LATER WEDNESDAY. GIVEN THE MODEL AGREEMENT HAVE
FAVORED THE HIGHER RESOLUTION GUIDANCE FROM THE NAM12 AND HRRR
THROUGH THE SHORT TERM PORTION OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE SHOWERS CONTINUING TO AFFECT THE FAR
EASTERN PART OF THE AREA ALONG THAT STALLED FRONT. TO THE WEST
LIGHT SHOWERS AND SPRINKLES WILL BE FOUND. THE DRIER AIR MOVES
INTO THE WESTERN PARTS OF EASTERN KENTUCKY TONIGHT INTO WEDNESDAY
ENDING ANY ACCUMULATING RAINS...THOUGH FOG AND LOW CLOUDS WILL
REMAIN INTO THE MORNING. HOWEVER...TO THE EAST THE SHOWERS WILL
LINGER WELL INTO THE DAY WEDNESDAY. ADDITIONALLY...A SECONDARY
COLD FRONT WILL MOVE INTO THE AREA ON WEDNESDAY EVENING AND
OVERNIGHT BRINGING A POTENTIAL FOR SPRINKLES OR FLURRIES TO AT
LEAST NORTHERN PARTS OF THE AREA. THE AIR WILL DRY OUT THROUGHOUT
THE STATE BY DAWN THURSDAY. COLDER AIR WILL GRADUALLY FILTER INTO
THE AREA THROUGH WEDNESDAY WITH A BIGGER SURGE THAT NIGHT FOR LOWS
BACK TO NEAR FREEZING BY DAWN THURSDAY.
USED THE SHORTBLEND AS A STARTING POINT FOR THE T AND TD GRIDS
INTO WEDNESDAY MORNING AND THE SUPERBLEND THEREAFTER. FROM THIS
MADE SOME MINOR...TERRAIN BASED...ADJUSTMENTS TO THE LOW
TEMPERATURES TONIGHT AND WEDNESDAY NIGHT. AS FOR POPS ENDED UP
SIMILAR TO MOS BLEND FOR TONIGHT AND WEDNESDAY THE ON THE HIGH
SIDE BY A TAD FOR WEDNESDAY NIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 215 PM EST TUE DEC 1 2015
AN EXTENDED STRETCH OF DRY WEATHER IS EXPECTED FOR THE ENTIRE
EXTENDED PERIOD AS A RIDGE BUILDS IN OVERHEAD AND REMAINS NEARLY
STATIONARY THROUGH THE UPCOMING WEEKEND. WITH PW`S AROUND 0.15
THROUGH THE WEEKEND...WE WILL LIKELY SEE SOME LARGE DIURNAL RANGES
EACH DAY WITH COLD MORNINGS AND MILD AFTERNOONS WITH HIGHS LIKELY
REACHING ABOVE MODEL GUIDANCE EACH DAY AND POSSIBLY UNDER GUIDANCE
AT NIGHT. NEXT CHANCE OF RAIN MAY COME SOMETIME AROUND NEXT
TUESDAY...ALTHOUGH GIVEN THE PATTERN GOING INTO TUESDAY...NOT
WILLING TO BITE ON THIS SYSTEM YET.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 725 PM EST TUE DEC 1 2015
WITH A COLD FRONT SLOWLY WORKING ACROSS THE REGION...MVFR TO IFR
CONDITIONS SHOULD PREVAIL ALONG WITH SOME FOG...DRIZZLE OR SHOWERS
FOR MUCH OF THE FIRST 12 TO 15 HOURS OF THE PERIOD. CIGS WILL BE
NEAR OR BELOW AIRPORT MINS IN SOME CASES FOR LOCATIONS IN CLOSER
PROXIMITY TO THE FRONT. THE CIGS AND VIS SHOULD IMPROVE TO MVFR OR
VFR BETWEEN 13Z TO 20Z AS HIGH PRESSURE AND DRIER AIR BUILD INTO
THE STATE. HOWEVER...AS AN UPPER LEVEL TROUGH AXIS APPROACHES...
STRATOCU SHOULD APPROACH OR MOVE INTO THE AREA NEAR THE END OF THE
PERIOD WITH SOME LOCATIONS RETURNING TO MVFR. WINDS WILL GENERALLY
BE WEST SOUTHWEST TO WEST NORTHWEST THROUGH THE PERIOD...AND
AVERAGE 10KT OR LESS IN MOST LOCATIONS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...JP
AREA FORECAST DISCUSSION
NWS DULUTH MN
1152 PM CST TUE DEC 1 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY AFTERNOON)
ISSUED AT 310 PM CST TUE DEC 1 2015
MAIN CONCERNS IN THE SHORT TERM REMAIN FOCUSED AROUND PERSISTENT
BAND OF SNOW AND RAIN ACROSS NORTHEAST MINNESOTA...AND THE
POTENTIAL FOR DRIZZLE CHANGING TO FREEZING DRIZZLE TONIGHT AND
WEDNESDAY MORNING.
A WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR A GOOD PORTION OF
NORTHEAST MINNESOTA FOR AN ADDITIONAL 1 TO 4 INCHES OF SNOW ACROSS
THE ARROWHEAD TONIGHT THROUGH 6 AM WEDNESDAY.
UPPER LOW CONTINUES TO ROTATE SLOWLY EWD ALONG THE MN/IA BORDER
THIS AFTERNOON...AS A BROADENING SFC LOW EXPANDS EAST INTO
WISCONSIN AND WRN LAKE SUPERIOR. THERE IS AN AREA OF WEAK MID-
LEVEL F-GEN ACROSS NE MN AIDING IN THE 700-500MB LIFT WHICH HAS
BEEN THE PRIMARY AREA OF FORCING THAT HAS LEAD TO THE DEVELOPMENT
OF THIS HEAVY SNOW BAND. LATEST RAP GUIDANCE HAS THIS LIFTING
LAYER HANGING AROUND THE ARROWHEAD THIS EVENING AND DISSIPATING
AFTER MIDNIGHT. SO...WILL CONTINUE TO HIGHLIGHT THE POTENTIAL FOR
ADDITIONAL SNOWFALL ALONG THE IRON RANGE AND INTO THE ARROWHEAD
TONIGHT AS THE BAND PIVOTS AND ROTATES EWD. MAY SEE THE SRN EDGE
OF THIS BAND BRUSH THE TWIN PORTS THIS EVENING...AND TRIGGER A FEW
LIGHT SNOW SHOWERS AND/OR PATCHY LIGHT FREEZING DRIZZLE. SO...WILL
KEEP SRN ST. LOUIS AND CARLTON COUNTY...INCLUDING DULUTH...IN THE
ADVISORY.
AS MENTIONED ABOVE...THERE IS THE POTENTIAL FOR PATCHY FREEZING
DRIZZLE ACROSS THE REGION TONIGHT AND WED MORNING. A LAYER OF
DRIER AIR ALOFT WILL CONTINUE TO PUSH IN FROM THE SOUTH AND ALLOW
THE COLUMN TO LOSE ICE CRYSTALS ALOFT...BUT KEEP THE LOW LEVEL
MOISTURE IN PLACE. THIS SETUP WILL BE CONDUCIVE FOR DRIZZLE THIS
EVENING...AND EVENTUALLY PATCHY FREEZING DRIZZLE LATER TONIGHT AND
WEDNESDAY MORNING AS NEAR-SFC TEMPERATURES COOL INTO THE UPPER 20S
AND LOWER 30S. ROADS AND OTHER SURFACES WILL LIKELY BE WET OR SNOW
COVERED...WHICH WILL INHIBIT THE POTENTIAL IMPACTS FROM THE
FREEZING DRIZZLE...SO DECIDED TO CANCEL THE WINTER WEATHER
ADVISORY FOR NW WI AND AREAS OF E-CENTRAL MN.
THE LINGERING SNOW SHOWERS AND LIGHT DZ/FZDZ WILL SWEEP EWD
THROUGH THE FORECAST AREA WED MORNING AS MOST OF THE AREA WILL
BEGIN TO CLEAR OUT INTO THE AFTERNOON. THE SNOW AND DRIZZLE WILL
LIKELY PERSIST ALONG THE SOUTH SHORE AND OVER N-CENTRAL WI WED
AFTERNOON...BUT WITH ONLY LIGHT AMOUNTS EXPECTED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 310 PM CST TUE DEC 1 2015
HIGH PRESSURE WILL MOVE OVER THE CENTRAL PLAINS ON WEDNESDAY NIGHT.
THERE IS A CHANCE OF LIGHT LAKE EFFECT SNOW SHOWERS WEDNESDAY NIGHT
OVER IRON COUNTY IN WISCONSIN AS LIGHT NORTHWESTERLY WINDS WILL SET
IN. THE HIGH PRESSURE SYSTEM WILL SLOWLY MOVE OFF TO THE EAST
THURSDAY AND BE OVER THE OHIO VALLEY ON FRIDAY WITH DRY WEATHER
CONDITIONS EXPECTED FOR THE REGION. A WEAK COLD FRONT WILL ENTER
WESTERN MINNESOTA ON SATURDAY MORNING THROUGH MOISTURE WILL BE
LIMITED AND THUS CONTINUED A DRY FORECAST WITH AN INCREASE IN CLOUD
COVER. THE FRONT WILL HAVE PUSHED THROUGH THE UPPER MIDWEST ON
SUNDAY AS THE NEXT HIGH PRESSURE SYSTEM BUILDS OVER THE CENTRAL
PLAINS. HIGH PRESSURE WILL DOMINATE THE WEATHER PATTERN THROUGH
TUESDAY. A WEAK SHORTWAVE WILL ENTER NORTH DAKOTA ON TUESDAY THAT
MAY BRING SOME LIGHT SNOW SHOWERS FOR NORTHERN MINNESOTA AND
NORTHERN WISCONSIN LATE TUESDAY. TEMPERATURES WILL BE MILD FOR THE
SEASON...AVERAGING SOME 10 DEGREES ABOVE NORMAL WITH HIGHS MAINLY
IN THE MID TO UPPER 30S THROUGHOUT THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1141 PM CST TUE DEC 1 2015
SNOW BAND CONTINUES TO SLOWLY GET NARROWER AND WEAKER ACROSS
KDLH...KHIB AND KBRD AS OF 0530Z...WITH MAINLY IFR CONDITIONS IN
THE SNOW BAND WITH KDLH DIPPING INTO LIFR. SNOW HAS ENDED FOR
KINL...BUT CEILINGS REMAIN LOW WITH LIFR CIELINGS. KHYR HAS BEEN
VFR. THIS SNOW BAND IS EXPECTED TO CONTINUE THE WEAKENING TREND
AND WILL ROTATE AND SLIDE EAST THROUGH 18Z TOMORROW...BRINGING IFR
CONDITIONS IN THE HEAVIEST PART OF THE SNOW BAND. CONDITIONS TO
GRADUALLY IMPROVE TO VFR AFTER 02Z. GUIDANCE SHOWING AN AREA OF
STRATUS SPREADING INTO THE AREA FROM THE NORTH AFTER 23Z...BUT
DO NOT HAVE VERY MUCH CONFIDENCE IN THIS AND HAVE LEFT OUT FOR
NOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 31 35 20 36 / 80 30 0 0
INL 23 30 19 36 / 50 0 0 0
BRD 29 35 16 37 / 90 10 0 0
HYR 25 35 18 35 / 20 20 0 0
ASX 28 37 22 38 / 50 30 10 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST WEDNESDAY FOR MNZ011-012-
018>021-025-026-035-037.
LS...NONE.
&&
$$
SHORT TERM...TENTINGER
LONG TERM...KK
AVIATION...LE
AREA FORECAST DISCUSSION...UPDATE
NWS JACKSON MS
1000 AM CST WED DEC 2 2015
.UPDATE...RAIN IS BASICALLY OVER FOR THE BULK OF THE FORECAST
AREA...ALTHOUGH A FEW SHOWERS COULD HANG AROUND THE SOUTHEAST MS
PINEBELT REGION FOR THE NEXT FEW HOURS. THE ACTUAL COLD FRONT HAS
ADVANCED WELL SOUTHEAST OF THE LOWER MS VALLEY AT THIS POINT...BUT
THE CLEARING LINE IS JUST NOW ENCROACHING ON THE NATCHEZ TRACE
CORRIDOR. EXPECTING THIS CLEARING LINE TO MAKE PROGRESS SOUTHEAST
THROUGH THE DAY...BUT DUE TO PARADE OF HIGHER CLOUDS ASSOCIATED WITH
THE UPPER JET...COMPLETELY CLEAR SKIES MAY NOT BE SEEN AROUND THE I-
59 CORRIDOR UNTIL VERY LATE THIS AFTERNOON OR EARLY THIS EVENING.
THOSE CLOUDS IN SOUTHEAST MS WILL LIMIT WARMING POTENTIAL WHILE
STRONGER COLD AIR ADVECTION UP IN THE NEIGHBORHOOD OF THE ARKLAMISS
DELTA WILL COUNTERACT SOLAR WARMING INFLUENCES...YIELDING HIGH
TEMPERATURES ROUGHLY RANGING FROM 55 TO 60 DEGREES ACROSS THE BOARD.
UPDATES TO THE PREVIOUS SHORT TERM FORECAST WERE RELATIVELY MINOR
AND HAVE BEEN SENT DOWN THE LINE. /BB/
&&
.AVIATION...THE TREND IS FOR IMPROVEMENT FOR THE REST OF THE DAY.
THERE ARE A FEW PATCHES OF MVFR CIGS REMAINING IN THE AREA SO HAVE
ACCOUNTED FOR THAT IN THE EASTERN SITES. ALSO...WHAT LITTLE LIGHT
RAIN REMAINS SHOULD NOT CAUSE VSBY RESTRICTIONS. ALL AREAS SHOULD BE
VFR THIS AFTERNOON AND BEYOND. /SW/
&&
.PREV DISCUSSION... /ISSUED 328 AM CST WED DEC 2 2015/
SHORT TERM...TODAY THROUGH THURSDAY NIGHT...SATELLITE AND SURFACE
OBSERVATIONS THIS MORNING SHOWING DRY AIR MOVING INTO THE REGION AS
CEILINGS RISE AND CLOUDS CLEAR FROM THE NW. FURTHER SE...HOWEVER...SW
FLOW/ISENTROPIC ASCENT CONTINUES TO WRING OUT AREAS OF MOSTLY LIGHT
RAIN. SOME CONVECTIVE ELEMENTS CONTINUE TO DEVELOP AS WELL AS MAUL
POCKETS MOVE THROUGH THE FLOW PATTERN.
THE MAUL POCKETS ARE SHOWN WELL IN THE 00Z JAN SOUNDING AS WELL AS
GFS BUFR AND HRRR MODEL SOUNDINGS. MODEL SOUNDINGS AND CAM DATA
INDICATE THAT THE CONVECTIVE ELEMENTS WILL DIMINISH SHORTLY AFTER
SUNRISE LEAVING JUST THE DIMINISHING SHIELD OF LIGHT RAIN FOR THE
REMAINDER OF THE MORNING. PRECIP SHOULD CLEAR THE AREA AT OR SHORTLY
AFTER NOON...FOLLOWED PRETTY RAPIDLY BY THE REMAINING CLOUD COVER.
DRY AIR WILL CONTINUE TO SETTLE INTO THE AREA DURING THE
AFTERNOON/EVENING. WHILE THE DRY AIR WILL PROMOTE RADIATIONAL
COOLING TONIGHT...PRESSURE GRADIENT WILL STILL BE AS SUCH TO PREVENT
WINDS FROM COMPLETELY CALMING. MINS IN THE 30S STILL LOOKS LIKE A
GOOD BET...BUT THE BEST RADIATIONAL COOLING CONDITIONS SETUP FOR
THURSDAY NIGHT WHERE LOW TO MID 30S APPEAR PROBABLE...POSSIBLY SOME
UPPER 20S IN THE FAR NE AREAS./26/
LONG TERM...FRIDAY THROUGH TUESDAY...SPLIT FLOW REGIME WILL
CONTINUE OVER THE CONUS FRIDAY WITH A SOUTHERN STREAM TROUGH AXIS
SHIFTING JUST EAST OF OUR CWA BY AFTERNOON RESULTING IN NORTHWEST
FLOW ALOFT. A >1030MB HIGH WILL BE CENTERED OVER THE OHIO AND
TENNESSEE VALLEYS PROVIDING A COOL DRY NORTH WIND OVER OUR CWA.
PWATS WILL BE AROUND A QUARTER OF AN INCH. THIS WILL LEAD TO A SUNNY
BUT COOLER THAN NORMAL DAY AS SITES TOP OUT IN THE MID TO UPPER 50S.
THE SURFACE HIGH WILL STRENGTHEN AS IT SHIFTS EAST TO THE MID
ATLANTIC SEABOARD BY SUNDAY. THIS WILL LIMIT RETURN FLOW OVER OUR
CWA THROUGH THE WEEKEND. MID LEVEL RIDGING WILL STRENGTHEN OVER OUR
CWA SATURDAY AND SHIFT EAST OF OUR CWA SUNDAY IN RESPONSE TO ANOTHER
CLOSED LOW MOVING OVER THE CENTRAL PLAINS. THIS WILL ALLOW DAYTIME
HIGHS TO MODERATE THROUGH THE WEEKEND BUT MORNING LOWS WILL REMAIN
SLIGHTLY BELOW NORMAL. MODELS STILL DIFFER SIGNIFICANTLY WITH THE
NEXT CLOSED LOW THAT WILL MOVE OVER THE CENTRAL AND SOUTHERN PLAINS
SUNDAY NIGHT AND MONDAY. THE CANADIAN IS THE SLOWEST AND FARTHEST
SOUTH WITH THE LOW SUNDAY MORNING OVER THE TEXAS/OKLAHOMA
PANHANDLES. THE EURO AND GFS ARE FARTHER NORTHEAST WITH THE EURO
BEING THE FARTHEST EAST OVER THE KANSAS/MISSOURI STATE LINE. MODELS
DIVERGE EVEN FURTHER MONDAY INTO TUESDAY WITH THE EURO BEING DRY
OVER OUR CWA TRACKING THE LOW NORTHEAST WHILE THE GFS IS WETTER FOR
OUR CWA TRACKING THE LOW EAST SOUTHEAST. HAVE MAINTAINED SOME
CONTINUITY WITH POPS FROM OUR PREVIOUS FCST WITH LOW POPS ACROSS THE
NORTHERN HALF OF THE CWA SUNDAY NIGHT AND MONDAY. DRY WEATHER IS
EXPECTED AGAIN AREAWIDE TUESDAY AND WEDNESDAY. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 59 35 56 33 / 18 1 3 5
MERIDIAN 58 34 56 30 / 27 1 4 6
VICKSBURG 59 36 55 33 / 9 0 2 5
HATTIESBURG 59 37 58 33 / 29 2 6 6
NATCHEZ 61 36 56 33 / 15 1 3 5
GREENVILLE 56 36 53 33 / 6 0 2 5
GREENWOOD 56 33 53 31 / 7 0 2 5
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
BB/SW/26/22
AREA FORECAST DISCUSSION
NWS JACKSON MS
328 AM CST WED DEC 2 2015
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT...SATELLITE AND SURFACE
OBSERVATIONS THIS MORNING SHOWING DRY AIR MOVING INTO THE REGION AS
CEILINGS RISE AND CLOUDS CLEAR FROM THE NW. FURTHER SE...HOWEVER...SW
FLOW/ISENTROPIC ASCENT CONTINUES TO WRING OUT AREAS OF MOSTLY LIGHT
RAIN. SOME CONVECTIVE ELEMENTS CONTINUE TO DEVELOP AS WELL AS MAUL
POCKETS MOVE THROUGH THE FLOW PATTERN.
THE MAUL POCKETS ARE SHOWN WELL IN THE 00Z JAN SOUNDING AS WELL AS
GFS BUFR AND HRRR MODEL SOUNDINGS. MODEL SOUNDINGS AND CAM DATA
INDICATE THAT THE CONVECTIVE ELEMENTS WILL DIMINISH SHORTLY AFTER
SUNRISE LEAVING JUST THE DIMINISHING SHIELD OF LIGHT RAIN FOR THE
REMAINDER OF THE MORNING. PRECIP SHOULD CLEAR THE AREA AT OR SHORTLY
AFTER NOON...FOLLOWED PRETTY RAPIDLY BY THE REMAINING CLOUD COVER.
DRY AIR WILL CONTINUE TO SETTLE INTO THE AREA DURING THE
AFTERNOON/EVENING. WHILE THE DRY AIR WILL PROMOTE RADIATIONAL
COOLING TONIGHT...PRESURE GRADIENT WILL STILL BE AS SUCH TO PREVENT
WINDS FROM COMPLETELY CALMING. MINS IN THE 30S STILL LOOKS LIKE A
GOOD BET...BUT THE BEST RADIATIONAL COOLING CONDITIONS SETUP FOR
THURSDAY NIGHT WHERE LOW TO MID 30S APPEAR PROBABLE...POSSIBLY SOME
UPPER 20S IN THE FAR NE AREAS./26/
.LONG TERM...FRIDAY THROUGH TUESDAY...SPLIT FLOW REGIME WILL
CONTINUE OVER THE CONUS FRIDAY WITH A SOUTHERN STREAM TROUGH AXIS
SHIFTING JUST EAST OF OUR CWA BY AFTERNOON RESULTING IN NORTHWEST
FLOW ALOFT. A >1030MB HIGH WILL BE CENTERED OVER THE OHIO AND
TENNESSEE VALLEYS PROVIDING A COOL DRY NORTH WIND OVER OUR CWA.
PWATS WILL BE AROUND A QUARTER OF AN INCH. THIS WILL LEAD TO A SUNNY
BUT COOLER THAN NORMAL DAY AS SITES TOP OUT IN THE MID TO UPPER 50S.
THE SURFACE HIGH WILL STRENGTHEN AS IT SHIFTS EAST TO THE MID
ATLANTIC SEABOARD BY SUNDAY. THIS WILL LIMIT RETURN FLOW OVER OUR
CWA THROUGH THE WEEKEND. MID LEVEL RIDGING WILL STRENGTHEN OVER OUR
CWA SATURDAY AND SHIFT EAST OF OUR CWA SUNDAY IN RESPONSE TO ANOTHER
CLOSED LOW MOVING OVER THE CENTRAL PLAINS. THIS WILL ALLOW DAYTIME
HIGHS TO MODERATE THROUGH THE WEEKEND BUT MORNING LOWS WILL REMAIN
SLIGHTLY BELOW NORMAL. MODELS STILL DIFFER SIGNIFICANTLY WITH THE
NEXT CLOSED LOW THAT WILL MOVE OVER THE CENTRAL AND SOUTHERN PLAINS
SUNDAY NIGHT AND MONDAY. THE CANADIAN IS THE SLOWEST AND FARTHEST
SOUTH WITH THE LOW SUNDAY MORNING OVER THE TEXAS/OKLAHOMA
PANHANDLES. THE EURO AND GFS ARE FARTHER NORTHEAST WITH THE EURO
BEING THE FARTHEST EAST OVER THE KANSAS/MISSOURI STATE LINE. MODELS
DIVERGE EVEN FURTHER MONDAY INTO TUESDAY WITH THE EURO BEING DRY
OVER OUR CWA TRACKING THE LOW NORTHEAST WHILE THE GFS IS WETTER FOR
OUR CWA TRACKING THE LOW EAST SOUTHEAST. HAVE MAINTAINED SOME
CONTINUITY WITH POPS FROM OUR PREVIOUS FCST WITH LOW POPS ACROSS THE
NORTHERN HALF OF THE CWA SUNDAY NIGHT AND MONDAY. DRY WEATHER IS
EXPECTED AGAIN AREAWIDE TUESDAY AND WEDNESDAY. /22/
&&
.AVIATION...LOW CLOUDS...LIGHT RAIN AND FOG WILL RESULT IN IFR
CONDITIONS FOR MUCH OF THE MORNING OVER MEI AND HBG. ELSEWHERE...
DRIER AIR MOVING INTO THE REGION WILL RESULT IN THE RAIN ENDING AND
RISING CEILINGS WITH FLIGHT RULES BECOMING VFR BY 15Z. VFR CONDITIONS
WILL RETURN TO MEI AND HBG BY 19Z./26/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 59 35 56 33 / 23 5 3 5
MERIDIAN 58 34 56 30 / 37 6 4 6
VICKSBURG 59 36 55 33 / 15 4 2 5
HATTIESBURG 59 37 58 33 / 43 8 6 6
NATCHEZ 61 36 56 33 / 20 5 3 5
GREENVILLE 57 36 53 33 / 6 4 2 5
GREENWOOD 57 33 53 31 / 10 4 2 5
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
26/22/
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
335 PM CST WED DEC 2 2015
.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 320 PM CST WED DEC 2 2015
LITTLE IN THE WAY OF SENSIBLE WX IS EXPECTED DURING THIS PERIOD OF
THE FORECAST. AS THE UPPER LEVEL CLOSED LOW OVER THE GREAT LAKES
CONTS TO PULL OFF TO THE EAST...THE SURFACE RIDGE AXIS WILL
DEVELOP EAST TONIGHT. WITH LIGHT WINDS AND CLEAR WINDS WE ARE
EXPECTING SOME PRETTY CHILLY LOWS OVER THE SNOW COVER AREAS TO
THE NORTH. ON THE SOUTHERN EDGE OF THE SNOW COVER WHERE THERE HAS
BEEN A GOOD DEAL OF MELTING TODAY WE MAY SEE SOME PATCHY FOG
DEVELOP OVERNIGHT WITH THE RESIDUAL LOW-LEVEL MOISTURE REMAINS IN
PLACE. THE RAP INDICATES THIS...AND THE SREF HAS SOME FAIRLY HIGH
PROBS OF LOWER VISBY OVERNIGHT IN THIS AREA AS WELL. THIS PATTERN
MAY AGAIN REPEAT ON THURSDAY NIGHT INTO FRIDAY MORNING. OTHERWISE
A GOOD DEAL OF SUN AND MELTING ARE EXPECTED DURING THE DAY ON
THU/FRI WITH WARMER HIGHS.
A STRONGER LOW-LEVEL JET DEVELOPS ON FRI NIGHT AHEAD OF A FRONTAL
BOUNDARY THAT WILL MOV ACROSS THE CWA ON LATE SAT. WE MAY SEE
ENOUGH LOW LEVEL LIFT/MOISTURE RETURN TO SEE STRATUS
DEVELOP...STARTING OVER THE WESTERN CWA EARLY IN THE NIGHT
EXPANDING EWD TOWARD SAT MRNG. THE DEPTH OF THE MOIST LAYER ISN`T
OVERLY DEEP...BUT WE WOULDN`T BE SURPRISED TO SEE A LITTLE DZ DVLP
WITHIN THIS BAND IF MOISTURE PROFILES END UP SIMILAR TO THE NAM.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 320 PM CST WED DEC 2 2015
THE FRONTAL BOUNDARY WILL BE SLIPPING THROUGH THE CWA ON SAT
EVNG/NIGHT...BUT LITTLE IN THE WAY OF COLD AIR IS EXPECTED BEHIND
THE FRONT WITH TEMPERATURES REMAINING ABOVE NORMAL THROUGH THE
REST OF THE EXTENDED FORECAST. WE WILL CONT TO MENTION A SCHC CHC
OF RA/SN ON SAT NIGHT IN THE SOUTH...BUT LATEST TRENDS INDICATE
THIS MAY BE ABLE TO BE REMOVED IN COMING FORECASTS. THE REST OF
THE EXTENDED FORECAST WILL BE DRY.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1110 AM CST WED DEC 2 2015
VFR CONDITIONS THROUGH THE PERIOD. NORTHWEST WINDS MAINLY 10 TO
15KTS WILL BECOME LIGHT NORTHWEST THEN LIGHT SOUTHWEST LATER
TONIGHT. DID NOT INCLUDE FOG WITH LIGHT WINDS AND CLEAR
SKIES...HOWEVER WITH WET GROUND/MELTING SNOW...COULD SEE SOME
PATCHY FOG.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOUSTEAD
LONG TERM...BOUSTEAD
AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1107 PM CST TUE DEC 1 2015
.SYNOPSIS...
ISSUED AT 315 PM CST TUE DEC 1 2015
H5 UA ANALYSIS FROM THIS MORNING HAD A CLOSED LOW OVER
FAR SERN SOUTH DAKOTA. THIS FEATURE HAS MIGRATED FROM SERN WYOMING
TO ITS CURRENT LOCATION OVER THE PAST 24 HOURS. AS OF MIDDAY...WV
IMAGERY HAS THIS FEATURE ROUGHLY OVER NWRN IA. HT FALLS DOWNSTREAM
OF THIS FEATURE WERE MOST PRONOUNCED AT THE TWIN CITIES AND THE QUAD
CITIES WITH HT FALLS OF 220 AND 190 METERS RESPECTIVELY...SO THIS
FEATURE SHOULD CONTINUE TO MIGRATE SLOWLY TO THE EAST OVER THE NEXT
24 HOURS. CURRENT VISIBLE SATELLITE IMAGERY HAS A BROAD SHIELD OF
ALTO STRATUS AND OVER WESTERN AND NORTH CENTRAL NEBRASKA WITH SOME
MID LEVEL CLOUD ENHANCEMENT NOTED FROM ROUGHLY VALENTINE TO NEAR
BROKEN BOW. UNDERNEATH THIS AREA OF ENHANCED CLOUDINESS...LIGHT TO
MODERATE SNOWFALL HAS OCCURRED ALONG THE HIGHWAY 83 CORRIDOR FROM
VALENTINE TO NORTH PLATTE THIS AFTERNOON. SOME BRIEF PERIODS OF
HEAVY SNOW WAS OCCURRING WITHIN THIS BAND...BUT GIVEN THE PROGRESSION
OF THIS AREA TO THE SOUTH SOUTHWEST...ANY ADDITIONAL ACCUMULATIONS
HAVE BEEN FAIRLY LIGHT. TEMPERATURES AS OF 3 PM CST...UNDER CLOUDY
SKIES...RANGED FROM 27 AT AINSWORTH AND VALENTINE...TO 33 AT
OGALLALA AND IMPERIAL.
&&
.UPDATE...
ISSUED AT 918 PM CST TUE DEC 1 2015
RADAR COVERAGE HAS DECREASED SUFFICIENTLY FOR THE WINTER WEATHER
ADVISORY TO BE CANCELLED.
UPDATE ISSUED AT 544 PM CST TUE DEC 1 2015
ANOTHER SNOW BAND HAS DRIFTED SOUTH OUT OF EASTERN SD. THE WINTER
WEATHER ADVISORY WILL BE EXTENDED UNTIL MIDNIGHT CST EAST OF
HIGHWAY 83. CHERRY COUNTY IS IN THE CLEAR AND HAS BEEN CANCELLED
FROM THE ADVISORY.
ISOLATED SNOW SHOWERS WILL LAST A FEW HOURS ACROSS SHERIDAN
COUNTY.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 315 PM CST TUE DEC 1 2015
TONIGHT AND WEDNESDAY...THE PRIMARY FOCUS IN THE SHORT TERM IS THE
END TIMING OF THE SNOW CURRENTLY FALLING OVER MUCH OF THE FORECAST
AREA. THEN THE FOCUS TURNS TO TEMPERATURES...MORE SPECIFICALLY HOW
COLD TEMPERATURES WILL FALL WITH A DENSE FRESH SNOWPACK IN PLACE.
THE UPPER LOW CONTINUES TO SLOWLY PULL EAST ACROSS NORTHERN IOWA
THIS AFTERNOON...DRAGGING ONE LAST SHORTWAVE ACROSS THE NORTHERN AND
CENTRAL HIGH PLAINS. THE APPROACH OF THE WAVE HELPED TO FOCUS A
BAND OF MODERATE TO HEAVY SNOWFALL OVER THE CENTRAL SANDHILLS...FROM
VALENTINE SOUTH TOWARD NORTH PLATTE. THE NAM MODEL...AND THE LATEST
RUNS OF THE HRRR DID A FINE JOB DEPICTING THIS ENHANCED SNOWBAND
BOTH IN TERMS OF INTENSITY AND LOCATION...THUS THE FORECAST WAS
TRENDED IN THAT DIRECTION. BOTH THE NAM AND THE LATEST HRRR SHOW
THE BAND ERODING IN A COUPLE HOURS...WITH AN ADDITIONAL WEAKER BAND
BECOMING FOCUSED ACROSS NORTH CENTRAL NEBRASKA SOUTH INTO CUSTER
COUNTY LATE AFTERNOON. REAL TIME OBSERVING STATIONS AND THE LATEST
RADAR TRENDS SUPPORT THE WEAKENING TREND...YIELDING GOOD CONFIDENCE
IN THE SHORT TERM.
THE CURRENT ADVISORY WILL CONTINUE UNTIL 00Z THIS EVENING...THOUGH
WE DO NOT EXPECT MUCH MORE IN THE WAY OF ACCUMULATIONS. WE WOULD
RATHER SEE HOW THE ADDITIONAL BAND PLAYS OUT BEFORE MAKING THE FINAL
CALL ON WHETHER TO CUT THE ADVISORY EARLY. WHERE THE PRESENT HEAVY
BAND SET UP...WE COULD STILL SEE SNOW RATES IN EXCESS OF A QUARTER
TO POSSIBLY AS MUCH AS AN HALF INCH PER HOUR...BUT AGAIN THAT BAND
IS SLOWLY FALLING APART.
TEMPERATURES OVERNIGHT ARE GOING TO BE HEAVILY DEPENDENT ON THE
AMOUNT OF CLEARING AND HOW LONG THE NORTHWEST WINDS STAY UP. AT
THIS POINT THE FORECAST CALLS FOR CLEARING A FEW HOURS BEFORE
DAWN...AND WITH A FRESH SNOWPACK...LOW TO MID TEENS ARE CERTAINLY
POSSIBLE. NOTE GUIDANCE IS SIGNIFICANTLY WARMER THAN WHAT WE ARE
FORECASTING. RISING HEIGHTS WILL ACCOMPANY WARMER TEMPERATURES ON
WEDNESDAY...BUT ONCE AGAIN TEMPERATURES WERE LOWERED SEVERAL DEGREES
FROM GUIDANCE DUE TO THE SNOWPACK. THE FORECAST CALLS FOR MID 30S
OVER THE SNOW AND NORTH CENTRAL NEBRASKA...TO THE LOWER 40S ACROSS
THE FAR WEST AND SOUTHWEST NEBRASKA WHERE A WESTERLY DOWNSLOPING
COMPONENT TO THE LOWER TROPOSPHERIC FLOW WILL BE MAXIMIZED. THE
FORECAST CALLS FOR DRY CONDITIONS ON WEDNESDAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 315 PM CST TUE DEC 1 2015
WEDNESDAY NIGHT THROUGH FRIDAY...THE MAIN FORECAST
CHALLENGES IN THE MID RANGE ARE TEMPERATURES AND THE THREAT FOR
FOG...ESPECIALLY FRIDAY MORNING. WITH RESPECT TO TEMPERATURES...EVEN
WITH EXPECTED MELTING ON WEDNESDAY...MOST OF WESTERN AND NORTH
CENTRAL NEBRASKA...SHOULD REMAIN SNOW COVERED. WITH EXPECTED
SNOW COVER AND LIGHT WESTERLY WINDS WEDNESDAY NIGHT...FELT GUIDANCE
WAS WAY OVERDONE...ESPECIALLY THE MAV...AND UNDERCUT BOTH THE MAV
AND MET TEMPS FOR LOWS WEDS NIGHT. IN ADDITION...GIVEN THE LIGHT
WESTERLY DRAINAGE WINDS...WENT WITH LOWS EVEN COLDER IN THE PLATTE
RIVER VALLEY WHERE SOME SINGLE DIGITS WERE INSERTED IN THE GRIDS.
FOR THURSDAY...WINDS WILL CONTINUE TO BE LIGHT WHICH WILL LIMIT
MIXING. WITH EXPECTED SNOW COVER IN PLACE...TEMPS WILL STRUGGLE TO
GET OUT OF THE LOWER 40S. THE EXCEPTION MAY BE IN THE FAR SOUTHERN
PORTION OF THE FORECAST AREA...WHERE SNOW COVER IS EXPECTED TO MELT
OFF WEDNESDAY. FOR THURSDAY NIGHT AND FRIDAY...I DID GO AHEAD AND
LIMIT LOWS IN THE PLATTE RIVER VALLEY WITH LIGHT WINDS EXPECTED IN
THE WESTERN CWA. FURTHER EAST...THE MODELS BEGIN TO INCREASE A
SURFACE PRESSURE GRADIENT THURSDAY NIGHT...IN RESPONSE TO A
DEEPENING SURFACE TROUGH OF LOW PRESSURE IN THE PANHANDLE. WITH TWO
DAYS OF MELTING SNOW...THE BOUNDARY LAYER WILL BE FAIRLY MOIST AND
WE MAY HAVE TO DEAL WITH THE THREAT FOR FOG FRIDAY MORNING. THE NAM
AND SREF ARE INDICATIVE OF A FOG THREAT FRIDAY AM...WHILE THE GFS IS
NOT. DECIDED TO HOLD OFF ON A FOG MENTION FOR NOW AS THIS IS WELL
INTO THE MID RANGE PERIOD AND WOULD LIKE TO SEE THE GFS/ECMWF COME
INTO BETTER AGREEMENT WITH THE SREF/NAM CAMP. ALSO...THERE IS SOME
DOUBT AS TO WINDS FRIDAY MORNING...AS THE NAM HAS SOME DECENT H925
WINDS IN AREAS WHERE THE BL IS NEARLY SATURATED. IF THE WINDS COME
TO FRUITION...THE FOG THREAT MAY BE DIMINISHED. STILL TOO MANY
DOUBTS YET TO INTRODUCE IT IN THE FORECAST.
BEYOND FRIDAY...A GENERAL WARMING TREND WILL COMMENCE AS ARCTIC AIR
REMAINS ABSENT FROM THE CONUS OVER THE NEXT 7 DAYS. HIGHS WILL
GENERALLY BE IN THE 40S TO LOWER 50S. THE EXCEPTION MAY BE SATURDAY
AS A DRY PACIFIC COLD FRONT PUSHES THROUGH THE CENTRAL PLAINS. THIS
WILL DROP HIGHS BACK INTO THE LOWER 40S...WITH HIGHS BACK IN THE 40S
TO LOWER 50S FOR SUNDAY...MONDAY AND TUESDAY. DRY CONDITIONS WILL
CONTINUE INTO THE MIDDLE OF NEXT WEEK AS A SECONDARY DRY TROUGH OF
LOW PRESSURE ALOFT TRACKS THROUGH THE NORTHERN PLAINS TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1106 PM CST TUE DEC 1 2015
THE UPPER LOW ACROSS WI CONTINUES TO MOVE STEADILY EAST.
VFR WILL LIKELY OVERSPREAD THE FCST AREA BY 12Z...15Z AT THE
LATEST. VFR IS EXPECTED ALL AREAS THEREAFTER THROUGH WEDNESDAY
EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CDC
SYNOPSIS...BUTTLER
SHORT TERM...JACOBS
LONG TERM...BUTTLER
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1018 AM EST WED DEC 2 2015
.SYNOPSIS...
A WAVE OF LOW PRESSURE WILL SHIFT ALONG A STALLED FRONT OVER CENTRAL
NEW YORK BRINGING ANOTHER ROUND OF RAIN ACROSS MUCH OF WESTERN AND
CENTRAL NEW YORK TODAY. TEMPERATURES TONIGHT AND THURSDAY WILL
EVENTUALLY BE COLD ENOUGH TO ALLOW RAIN TO MIX WITH OR CHANGE OVER
TO SNOW BEFORE TAPERING OFF...ALTHOUGH AMOUNTS SHOULD BE MINIMAL.
HIGH PRESSURE THEN BUILDS BACK IN FOR THE WEEKEND WITH DRY
CONDITIONS AND ABOVE NORMAL TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
A STALLED FRONT IS ANALYZED GENERALLY ALONG THE SPINE OF THE
APPALACHIANS THIS MORNING. A WAVE OF LOW PRESSURE ON THE FRONT OVER
WEST VIRGINIA WILL CONTINUE TO SHIFT NORTH ALONG THE FRONT TODAY
WHILE SPREADING ANOTHER ROUND OF RAINFALL ACROSS MUCH OF WESTERN AND
CENTRAL NEW YORK. REGIONAL RADAR SHOWS A LARGE AREA OF RAIN OVER
PENNSYLVANIA PUSHING NORTH INTO THE SOUTHERN TIER AND GENESEE RIVER
VALLEY. HAVE SHIFTED THE RAIN FURTHER WEST AND INCREASED POPS WITH
THE MORNING UPDATE BASED ON 12Z NAM AND HRRR RUNS. THE WESTERN EDGE
OF THE PRECIP SHIELD WILL GLANCE NEAR OR JUST EAST OF BUFFALO AND
NIAGARA FALLS WITH ALL LOCATIONS EAST OF THIS LINE PICKING UP A
TENTH TO AROUND A QUARTER OF AN INCH WITH THIS HIGHER AMOUNT FALLING
ACROSS THE FINGER LAKES AND NORTH COUNTY. OUTSIDE OF THE
RAIN...EXPECT ANOTHER CLOUDY DAY AS THE WESTERN EDGE OF CLEARING
WILL LIKELY REMAIN OVER CENTRAL LAKE ERIE AND JUST WEST OF LAKE
ONTARIO. TEMPS WILL NOT FLUCTUATE MUCH TODAY HOLDING IN THE MID 40S.
TONIGHT...THE SURFACE WAVE WILL SHIFT OVER NEW ENGLAND WITH SOME
WRAP AROUND MOISTURE LINGERING ACROSS MUCH OF CENTRAL NEW YORK.
THERE WILL BE A SHORT PERIOD OF TIME WHERE WESTERN NEW YORK WILL SEE
SOME DRY TIME BEFORE THE UPPER TROUGH SHIFTS ACROSS NEW YORK
BRINGING ANOTHER SHOT OF WIDE SPREAD MOISTURE AND CHANCES FOR
RAIN TO MIX WITH AND CHANGE TO SOME SNOW AS COLDER AIR ARRIVES.
WINDS WILL BECOME MORE WESTERLY WHICH SHOULD DIRECT ANY ACCUMULATING
SNOW TO THE HIGHER TERRAIN OF THE FAR WESTERN SOUTHERN TIER AND TUG
HILL. TOTALS SHOULD RUN AROUND AND INCH OR LESS. ACROSS LOWER
ELEVATIONS INCLUDING THE MAJOR METRO AREAS THERE MAY BE A RAIN/SNOW
MIX LATE OVERNIGHT BUT NO ACCUMULATION IS EXPECTED. THUS THE
SNOWLESS CONDITION FOR BUFFALO WILL LIKELY REMAIN SO FOR A WHILE TO
COME. LOW TEMPERATURES TONIGHT WILL BE IN THE LOWER 30S ACROSS THE
INTERIOR HILLS...AND THE MID 30S ALONG THE SHORES OF THE GREAT LAKES
AND LAKE PLAINS TO THE FINGER LAKES.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
ON THURSDAY A SHARP MID LEVEL CLOSED LOW WILL MOVE FROM THE OTTAWA
VALLEY TO NORTHERN NEW ENGLAND. SEVERAL LOBES OF VORTICITY ROTATING
AROUND THE CLOSED LOW WILL CROSS THE LOWER LAKES AND BRING PERIODS
OF ENHANCED ASCENT. THIS WILL COMBINE WITH ABUNDANT WRAP AROUND
MOISTURE TO PRODUCE SCATTERED TO NUMEROUS SHOWERS OF RAIN AND WET
SNOW ACROSS THE AREA. TEMPERATURES ALOFT WILL GROW JUST COLD ENOUGH
TO SUPPORT SOME MODEST LAKE ENHANCEMENT AS LAKE INDUCED EQUILIBRIUM
LEVELS RISE TO AROUND 11K FEET. THE MAIN FORCING FOR MORE PERSISTENT
PRECIPITATION WILL BE UPSLOPE FLOW IN THIS TYPE OF SETUP...WITH THE
GREATEST QPF FOUND ACROSS THE HIGHER TERRAIN OF THE CHAUTAUQUA RIDGE
JUST INLAND FROM LAKE ERIE AND ACROSS THE TUG HILL AND WESTERN
ADIRONDACKS EAST OF LAKE ONTARIO. PRECIPITATION COVERAGE AND
INTENSITY SHOULD PEAK MID TO LATE MORNING THURSDAY CORRESPONDING TO
THE BEST SYNOPTIC SCALE FORCING AND MOISTURE...WITH A SLOW
DIMINISHING TREND DURING THE AFTERNOON.
BOUNDARY LAYER TEMPERATURES WILL BE MARGINAL FOR RAIN VS. WET SNOW
AND WILL BRING PTYPE ISSUES INTO PLAY. ACROSS LOWER ELEVATIONS
EXPECT A MIX OF RAIN AND WET SNOW...WITH THE BEST TIME FRAME FOR WET
SNOW BEING THURSDAY MORNING WHEN THE BOUNDARY LAYER WILL BE
COOLEST...AND PRECIP THE STEADIEST RESULTING IN SOME EVAPORATIVE AND
DYNAMIC COOLING. ACROSS HIGHER ELEVATIONS TEMPERATURES SHOULD DROP
TO NEAR THE FREEZING MARK AND SUPPORT A CHANGE TO ALL WET SNOW FOR
MOST OF THE DAY. EXPECT ACCUMULATIONS OF AROUND AN INCH ACROSS THE
HIGHER TERRAIN FROM SOUTHERN ERIE AND WYOMING COUNTIES INTO THE
WESTERN SOUTHERN TIER...AND ALSO THE TUG HILL AND WESTERN FOOTHILLS
OF THE ADIRONDACKS. THE BRISTOL HILLS SHOULD ALSO SEE AROUND AN
INCH. ACROSS LOWER ELEVATIONS TEMPERATURES WILL REMAIN SEVERAL
DEGREES ABOVE FREEZING...AND THIS WILL LIKELY PREVENT ANY
ACCUMULATION.
IF BUFFALO CAN ESCAPE THIS PERIOD WITH NO MEASURABLE SNOW... A NEW
RECORD WILL BE SET FOR THE LATEST FIRST MEASURABLE SNOW. IN FACT THE
RECORD WOULD BE SHATTERED WITH LITTLE SNOW POTENTIAL IN THE LONG
TERM THROUGH AT LEAST DAY 10. THE PREVIOUS LATEST MEASURABLE SNOW ON
RECORD AT BUFFALO WAS DECEMBER 3RD SET IN 1899.
THURSDAY WILL BE THE COOLEST DAY OF THE NEXT 7...BUT STILL ONLY NEAR
AVERAGE WITH HIGHS AROUND 40 AT LOWER ELEVATIONS AND MID 30S HIGHER
TERRAIN.
THURSDAY NIGHT THE MID LEVEL LOW AND DEVELOPING SECONDARY COASTAL
CYCLOGENESIS WILL MOVE EAST INTO THE CANADIAN MARITIMES. WRAP AROUND
MOISTURE AND ASCENT WILL STEADILY DIMINISH ACROSS THE AREA. EXPECT
SCATTERED UPSLOPE/LAKE ENHANCED SNOW SHOWERS DURING THE EVENING
SOUTHEAST OF LAKE ERIE TO END OVERNIGHT AS MOISTURE BECOMES TOO
SHALLOW. A FEW SCATTERED SNOW SHOWERS MAY PERSIST EAST OF LAKE
ONTARIO THROUGH THE NIGHT...POSSIBLY MIXED WITH RAIN NEAR THE LAKE.
ANY ADDITIONAL AMOUNTS WILL BE VERY LIGHT AND SPOTTY.
ON FRIDAY A SHARP BUT MOISTURE STARVED MID LEVEL TROUGH MOVES ACROSS
THE LOWER LAKES AND NEW ENGLAND. IN MOST AREAS THIS WILL JUST BRING
SOME ADDITIONAL CLOUD COVER. EAST OF LAKE ONTARIO THERE MAY BE JUST
ENOUGH ADDITION OF LAKE MOISTURE AND INSTABILITY COMBINED WITH THE
SYNOPTIC SCALE TROUGH TO SUPPORT A FEW RAIN OR SNOW SHOWERS. EXPECT
HIGHS IN THE MID 40S ACROSS LOWER ELEVATIONS AND UPPER 30S TO AROUND
40 ACROSS HIGHER TERRAIN.
FRIDAY NIGHT ANY SCATTERED RAIN AND SNOW SHOWERS EAST OF LAKE
ONTARIO WILL END. OTHERWISE A RIDGE OF HIGH PRESSURE SURFACE AND
ALOFT WILL BUILD EAST ACROSS THE OHIO VALLEY AND BRING CLEARING
SKIES TO OUR REGION.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
THE LONG TERM PERIOD WILL FEATURE A PERIOD OF RARE BENIGN WEATHER
FOR EARLY METEOROLOGICAL WINTER WITH VERY MILD TEMPERATURES AND DRY
WEATHER.
OVER THE WEEKEND A STRONG RIDGE SURFACE AND ALOFT WILL BUILD ACROSS
THE OHIO VALLEY AND LOWER LAKES. THIS WILL PROVIDE PLENTY OF
SUNSHINE AND TEMPERATURES WELL ABOVE AVERAGE...WITH HIGHS IN THE
LOWER 50S ACROSS LOWER ELEVATIONS BOTH SATURDAY AND SUNDAY. THE DRY
WEATHER CONTINUES INTO AT LEAST MONDAY AS SURFACE HIGH PRESSURE
REMAINS IN PLACE.
BY TUESDAY MODEL GUIDANCE BEGINS TO DIVERGE WITH THE HANDLING OF A
CLOSED LOW LIFTING OUT OF THE DEEP SOUTH. THE LATEST 00Z GFS BRINGS
THIS LOW THROUGH THE OHIO VALLEY AND TOWARDS THE LOWER LAKES LATER
TUESDAY AND WOULD SPREAD RAIN INTO THE REGION. THE 00Z ECMWF MOVES
THIS SYSTEM IN A MORE EASTERLY DIRECTION THROUGH THE MID ATLANTIC
STATES...KEEPING OUR REGION DRY. THE GEFS ENSEMBLES SHOW A GOOD
AMOUNT OF VARIABILITY WITH SOME MEMBERS FOLLOWING THE OPERATIONAL
SOLUTION AND SOME MORE IN THE ECMWF CAMP. GIVEN THE MODEL
UNCERTAINTY AND TIME RANGE FOR NOW WILL JUST STICK WITH THE
PREVIOUS CONTINUITY OF A DRY FORECAST FOR TUESDAY.
LOOKING A LITTLE FARTHER AHEAD...THERE IS HIGH CONFIDENCE THAT THE
MILD PATTERN WILL CONTINUE FOR THE NEXT 10-12 DAYS AS PACIFIC AIR
CONTINUES TO FLOOD THE NATION. BY THE MIDDLE OF DECEMBER...THE PAST
FEW RUNS OF THE GEFS ENSEMBLES SHOW MORE VARIABILITY IN THE LONGWAVE
PATTERN ACROSS NORTH AMERICA...WITH A FAIR NUMBER OF ENSEMBLE
MEMBERS SHOWING A PATTERN MORE CONDUCIVE TO ALLOWING COLD AIR TO
DRAIN SOUTH INTO THE NORTHERN TIER OF THE US. THIS IS STILL A VERY
LONG WAYS OFF...BUT SOMETHING TO WATCH AS WE HEAD TOWARDS THE MIDDLE
OF THE MONTH.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
STALLED FRONT ACROSS CENTRAL NY WITH SURFACE WAVE OF LOW
PRESSURE LIFTING NORTHEAST TOWARD NEW ENGLAND THROUGH TODAY.
THIS WILL MAINTAIN CLOUD COVER ACROSS THE REGION WITH RAIN EXPECTED
GENERALLY EAST OF KBUF/KIAG/KJHW ALTHOUGH ANY SLIGHT SHIFT TO THE
WEST MAY BRING LIGHT RAIN TO THE NIAGARA FRONTIER. LIFR WILL LINGER
ACROSS THE SOUTHERN TIER THROUGH TODAY AND TONIGHT. VFR CIGS AT
KBUF/KIAG/KART WILL FALL TO MVFR CIGS ALONG WITH KROC LATER TODAY
INTO THE OVERNIGHT AS RAIN EXPANDS NORTH. TONIGHT COLDER AIR ARRIVES
WITH SOME RAIN MIXING WITH THEN CHANGING TO SNOW WHICH WILL LOWER
VIS TO IFR AT KART AND KJHW.
OUTLOOK...
THURSDAY...MAINLY VFR. A CHANCE OF RAIN OR SNOW SHOWERS
EARLY.
FRIDAY TO SUNDAY...VFR.
&&
.MARINE...
A SHORT LULL IN ELEVATED WINDS AND WAVES WILL OCCUR TODAY AS A WEAK
WAVE OF LOW PRESSURE SHIFTS NORTH ALONG A STALLED FRONT OVER CENTRAL
NEW YORK. SMALL CRAFT ADVISORIES THEN LOOK TO BE NEEDED THURSDAY AS
NORTHWESTERLY FLOW FRESHENS AND THE PRESSURE GRADIENT TIGHTENS
BETWEEN DEPARTING THE LOW PRESSURE OVER NEW ENGLAND AND HIGH
PRESSURE BUILDING IN FROM THE MIDWEST.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SMITH
NEAR TERM...SMITH
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...SMITH
MARINE...SMITH/WCH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1257 PM EST WED DEC 2 2015
.SYNOPSIS...A COLD FRONT PUSHES THROUGH THE REGION TONIGHT.
BEHIND THE FRONT...HIGH PRESSURE BUILDS INTO THE AREA FOR THE
REMAINDER OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1020 AM WEDNESDAY...
ONLY VERY PATCHY DENSE FOG WAS OBSERVED IN CENTRAL NORTH CAROLINA AS
LATE MORNING APPROACHED...SO THE DENSE FOG ADVISORY HAS BEEN ALLOWED
TO EXPIRE. SATELLITE IMAGERY SHOWED GOOD DIFFLUENCE OVER CENTRAL
NORTH CAROLINA AHEAD OF UPPER-LEVEL LOW PRESSURE THAT WILL MOVE OVER
THE WESTERN GREAT LAKES. WEAK MID-LEVEL SHORTWAVES WILL MOVE INTO
CENTRAL NORTH CAROLINA IN THE SOUTHWEST FLOW ALOFT...AS PRECIPITABLE
WATER VALUES INCREASE...EVEN OVER THE COASTAL PLAIN...TO GENERALLY
AROUND 1.5 INCHES THIS AFTERNOON. THE COLD FRONT MOVING INTO THE
MOUNTAINS SHOULD ONLY VERY SLOWLY MOVE EAST...WITH NUMEROUS TO AT
TIMES MORE WIDESPREAD SHOWERS OCCURRING AHEAD OF IT. SHOWERS COULD
BE QUITE SCATTERED FOR A WHILE IN THE COASTAL PLAIN...WHERE
PRECIPITABLE WATER VALUES ON THE SPC MESOANALYSIS ARE NEAR AN INCH
AT BEST AS OF THIS WRITING...AND FARTHEST FROM THE MID- AND UPPER-
LEVEL JET SUPPORT TO THE NORTHWEST OF CENTRAL NORTH CAROLINA. THE
MORE NUMEROUS SHOWERS MAY NOT OCCUR THERE UNTIL LATER THIS AFTERNOON
AND INTO THE OVERNIGHT...AND MAY NEED TO INTRODUCE CATEGORICAL
CHANCES FOR THAT AREA INTO THE EVENING AS THE RAP FORECASTS
PRECIPITABLE WATER VALUES THERE ACTUALLY INCREASING TO OVER 1.5
INCHES BY 00Z OR SO.
700MB TEMPERATURES ARE FORECAST TO COOL ON RAP MODEL SOUNDINGS...BUT
THE TEMPERATURE PROFILE ALOFT WARMS A LITTLE AND THE POTENTIAL FOR
THUNDER SEEMS REMOTE. 0-3KM MLCAPE BASICALLY ONLY REGISTERS NEAR AND
OFFSHORE...COINCIDENT WITH THE SPC OUTLOOK...BUT WITH A SLIGHT
CHANCE OF THUNDER IN THE FORECAST AND MUCAPE BETWEEN ABOUT 100 AND
300J/KG AREAWIDE...WILL CONTINUE THE MENTION OF A SLIGHT CHANCE
AHEAD OF THE FRONT AND AS 700MB TEMPERATURES COOL. WITH THE CLOUDS
AND SHOWERS HIGHS ARE FORECAST ON THE LOW END OF MOS GUIDANCE BUT
LIKE THE TREND FOR NOW THOUGH PARTS OF THE TRIAD IN PARTICULAR COULD
END UP A COUPLE OF DEGREES WARMER WITH KGSO IN THE UPPER 50S ALREADY
AS OF THIS WRITING. OVERNIGHT...THE COLD FRONT SHOULD PROGRESS
THROUGH CENTRAL NC FROM NW TO SE BETWEEN 00Z AND 09Z THURSDAY.
DRYING OCCURS BEHIND THE FRONT...WITH PROBABLY PRETTY LIMITED
CHANCES OF PRECIPITATION IN THE TRIAD BY 02Z...TRIANGLE BY AROUND
05Z...AND THE COASTAL PLAIN LATER IN THE OVERNIGHT. OVERNIGHT LOWS
WILL RANGE FROM THE UPPER 30S NW TO UPPER 40S SE.
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 300 AM WEDNESDAY...
CLOSED LOW OVER AND ASSOCIATED UPPER TROUGH WILL SLOWLY EXIT THE NEW
ENGLAND AND THE NORTHEAST ON THURSDAY. ATTENDANT SFC COLD FRONT AND
ACCOMPANYING BAND OF CONVECTION WILL BE WELL OFFSHORE BY DAYBREAK
THURSDAY AS POST-FRONTAL COLD DRY AIR ADVECTION WILL SUPPORT TEMPS A
FEW DEGREES BELOW NORMAL ON THURSDAY. CONTINUED SWLY FLOW ALOFT MAY
SUPPORT A FAIRLY EXTENSIVE CANOPY OF HIGH CLOUDS WELL INTO THE
AFTERNOON...MAINLY ACROSS EASTERN NC. ADDITIONALLY...STRONG/TIGHT
PRESSURE GRADIENT TO START THE DAY WILL QUICKLY RELAX BY THE EARLY
AFTERNOON. THUS EXPECT TO SEE THE STRONGEST NWLY WIND GUSTS BY
LUNCHTIME...IN THE 22 TO 25KT RANGE...DIMINISHING INTO THE TEENS BY
THE AFTERNOON.
HIGHS RANGING FROM LOWER 50S NORTH TO MID/UPPER 50S SOUTH. LOWS
THURSDAY NIGHT IN THE UPPER 20S TO LOWER 30S.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 100 PM WEDNESDAY...
THE FIRST THREE DAYS OF THE LONG TERM LOOK VERY PLEASANT AS A STRONG
1040 MB HIGH PRESSURE SITS OVER THE OHIO VALLEY WITH VERY WEAK FLOW
ALOFT. LOOKING AT FORECAST SOUNDINGS...THE ENTIRE COLUMN IS VERY DRY
WITH A PARCHED PRECIPITABLE WATER VALUES OF 0.15-0.25 INCHES ON
THROUGH THE WEEKEND. AND THEREFORE EXPECT AN ABUNDANCE OF SUNSHINE
FRIDAY AND SATURDAY WITH PERHAPS A FEW LOW CLOUDS SNEAKING IN ON
SUNDAY AS THE HIGH MIGRATES TO THE EAST AND COMES INTO A LITTLE BIT
BETTER POSITIONING FOR COLD AIR DAMMING AND MOISTURE TRANSPORT OFF
OF THE ATLANTIC INCREASES SLIGHTLY. TEMPERATURES WILL BE RIGHT
AROUND NORMAL WITH HIGHS IN THE MID TO UPPER 50S AND LOWS IN THE LOW
TO MID 30S THROUGH SUNDAY NIGHT.
THE FIRST SYSTEM OF CONCERN IN THE LONG TERM WILL ENTER THE PICTURE
EARLY NEXT WEEK AS A SURFACE LOW FORMS OVER THE SOUTHEAST ATLANTIC
AND BEGINS MOVING UP THE COAST. AT THE SAME TIME...A STRONG UPPER
LEVEL LOW WILL DEVELOP OVER THE PLAINS AND MISSISSIPPI VALLEY AND
TRACK EASTWARD. AS THESE TWO SYSTEM GET CLOSER TO EACH OTHER THEY
WILL RESEMBLE A MILLER B PATTERN (LACKING A SURFACE LOW UNDER THE
UPPER LEVEL LOW IN THE WEST) MOVING UP THE COAST. DEPENDING ON
TIMING...THE WESTERN LOW COULD GET INGESTED INTO THE COASTAL LOW
(GFS SOLUTION) OR THE WESTERN LOW COULD BE TOO LATE TO CATCH UP WITH
THE FIRST (ECMWF SOLUTION). REGARDLESS OF WHICH SCENARIO PLAYS OUT
THE UPSHOT FOR CENTRAL NC SHOULD BE THE SAME...INCREASING RAIN
CHANCES FOR MONDAY AND TUESDAY AND CLEARING OUT BY WEDNESDAY
AFTERNOON. THE ONLY QUESTION IS IF THE BULK OF THE RAIN WILL COME ON
MONDAY OR TUESDAY. THE LATEST RUN OF THE GFS HAS COME IN MUCH SLOWER
AND HOLDS OFF THE RAIN CHANCES UNTIL TUESDAY WHEREAS THE ECMWF MOVES
THE SYSTEM THROUGH MUCH EARLIER WITH THE BULK OF THE RAIN ON MONDAY
AND CLEARING OUT ON TUESDAY BEFORE IT HAS THE SYSTEM BOMBING OUT
OVER THE ATLANTIC AS IT STEAMS TOWARDS NOVA SCOTIA. TO ALLOW FOR
SOME WIGGLE ROOM...WILL INTRODUCE POPS ON MONDAY WITH HIGHEST POPS
MONDAY NIGHT/EARLY TUESDAY AND BACKING OFF BY TUESDAY NIGHT.
TEMPERATURES WILL REMAIN FAIRLY STEADY THROUGH THIS TIME WITH HIGHS
IN THE MID TO UPPER 50S WITH LOWS MODERATING INTO THE UPPER 30S TO
MIDDLE 40S AS CLOUD COVER BECOMES MORE PROMINENT AT NIGHT.
WEDNESDAY WILL SEE A RETURN OF PARTLY CLOUDY TO MOSTLY CLEAR SKIES
AS RELATIVE HIGH PRESSURE AND RIDGING ALOFT MOVES IN OVER THE AREA.
TEMPERATURES ONCE AGAIN WILL REMAIN IN THE 50S ACROSS MUCH OF THE
AREA.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 1255 PM WEDNESDAY...
SUB-VFR CONDITIONS...A COMBINATION OF MVFR AND IFR ESPECIALLY IN
TERMS OF CEILINGS...WILL IMPROVE TO WIDESPREAD VFR FROM WEST TO EAST
TONIGHT. NUMEROUS TO WIDESPREAD SHOWERS WILL DIMINISH FOLLOWING A
COLD FRONT...WITH THE THREAT OF EVEN AN ISOLATED SHOWER ABOUT ENDED
IN THE IMMEDIATE TRIAD BY 02Z...AND IN ALL OF CENTRAL NORTH CAROLINA
AGAIN BY 09Z. BY 12Z THURSDAY...AND LIKELY BY 09Z THURSDAY...VFR
CONDITIONS SHOULD PREVAIL ACROSS CENTRAL NORTH CAROLINA. SOME
GUIDANCE SUGGESTS THE POTENTIAL FOR RENEWED LOWER VISIBILITIES THIS
EVENING ESPECIALLY IN THE COASTAL PLAIN PRIOR TO COLD FRONTAL
PASSAGE. THERE ARE LOWER VISIBILITIES FOR A PERIOD THIS EVENING IN
THE FORECASTS FOR KRWI AND KFAY AS A RESULT.
IN THE WAKE OF THE COLD FRONT MOVING THROUGH CENTRAL NORTH CAROLINA
SURFACE WINDS VEER TO NORTHWEST-TO-NORTH. A RELATIVELY TIGHT SURFACE
GRADIENT DEVELOPING AS HIGH PRESSURE BUILDS IN WILL RESULT IN SOME
WIND GUSTS WITH MIXING THURSDAY TO THE LOWER 20S KNOTS. AN UPPER JET
OVERHEAD SHOULD HOLD SOME CIRRUS ACROSS MUCH OF CENTRAL NORTH
CAROLINA INTO THURSDAY...AND THAT MAY LIMIT SLIGHTLY MIXING AND WIND
GUST POTENTIAL...WHICH BASED ON THE GFS COULD BE INTO THE UPPER 20S
KNOTS TOWARD KRWI IF VERY GOOD MIXING WOULD BE REALIZED LATE
THURSDAY MORNING.
BEYOND THE 18Z VALID TAF PERIOD...VFR CONDITIONS SHOULD PREVAIL
THROUGH THE WEEKEND. THE NEXT THREAT FOR ADVERSE AVIATION CONDITIONS
WOULD COME BY LATE MONDAY AND MONDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...KS/DJF
NEAR TERM...10/DJF
SHORT TERM...CBL
LONG TERM...ELLIS
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1255 PM EST WED DEC 2 2015
.SYNOPSIS...A COLD FRONT PUSHES THROUGH THE REGION TONIGHT.
BEHIND THE FRONT...HIGH PRESSURE BUILDS INTO THE AREA FOR THE
REMAINDER OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1020 AM WEDNESDAY...
ONLY VERY PATCHY DENSE FOG WAS OBSERVED IN CENTRAL NORTH CAROLINA AS
LATE MORNING APPROACHED...SO THE DENSE FOG ADVISORY HAS BEEN ALLOWED
TO EXPIRE. SATELLITE IMAGERY SHOWED GOOD DIFFLUENCE OVER CENTRAL
NORTH CAROLINA AHEAD OF UPPER-LEVEL LOW PRESSURE THAT WILL MOVE OVER
THE WESTERN GREAT LAKES. WEAK MID-LEVEL SHORTWAVES WILL MOVE INTO
CENTRAL NORTH CAROLINA IN THE SOUTHWEST FLOW ALOFT...AS PRECIPITABLE
WATER VALUES INCREASE...EVEN OVER THE COASTAL PLAIN...TO GENERALLY
AROUND 1.5 INCHES THIS AFTERNOON. THE COLD FRONT MOVING INTO THE
MOUNTAINS SHOULD ONLY VERY SLOWLY MOVE EAST...WITH NUMEROUS TO AT
TIMES MORE WIDESPREAD SHOWERS OCCURRING AHEAD OF IT. SHOWERS COULD
BE QUITE SCATTERED FOR A WHILE IN THE COASTAL PLAIN...WHERE
PRECIPITABLE WATER VALUES ON THE SPC MESOANALYSIS ARE NEAR AN INCH
AT BEST AS OF THIS WRITING...AND FARTHEST FROM THE MID- AND UPPER-
LEVEL JET SUPPORT TO THE NORTHWEST OF CENTRAL NORTH CAROLINA. THE
MORE NUMEROUS SHOWERS MAY NOT OCCUR THERE UNTIL LATER THIS AFTERNOON
AND INTO THE OVERNIGHT...AND MAY NEED TO INTRODUCE CATEGORICAL
CHANCES FOR THAT AREA INTO THE EVENING AS THE RAP FORECASTS
PRECIPITABLE WATER VALUES THERE ACTUALLY INCREASING TO OVER 1.5
INCHES BY 00Z OR SO.
700MB TEMPERATURES ARE FORECAST TO COOL ON RAP MODEL SOUNDINGS...BUT
THE TEMPERATURE PROFILE ALOFT WARMS A LITTLE AND THE POTENTIAL FOR
THUNDER SEEMS REMOTE. 0-3KM MLCAPE BASICALLY ONLY REGISTERS NEAR AND
OFFSHORE...COINCIDENT WITH THE SPC OUTLOOK...BUT WITH A SLIGHT
CHANCE OF THUNDER IN THE FORECAST AND MUCAPE BETWEEN ABOUT 100 AND
300J/KG AREAWIDE...WILL CONTINUE THE MENTION OF A SLIGHT CHANCE
AHEAD OF THE FRONT AND AS 700MB TEMPERATURES COOL. WITH THE CLOUDS
AND SHOWERS HIGHS ARE FORECAST ON THE LOW END OF MOS GUIDANCE BUT
LIKE THE TREND FOR NOW THOUGH PARTS OF THE TRIAD IN PARTICULAR COULD
END UP A COUPLE OF DEGREES WARMER WITH KGSO IN THE UPPER 50S ALREADY
AS OF THIS WRITING. OVERNIGHT...THE COLD FRONT SHOULD PROGRESS
THROUGH CENTRAL NC FROM NW TO SE BETWEEN 00Z AND 09Z THURSDAY.
DRYING OCCURS BEHIND THE FRONT...WITH PROBABLY PRETTY LIMITED
CHANCES OF PRECIPITATION IN THE TRIAD BY 02Z...TRIANGLE BY AROUND
05Z...AND THE COASTAL PLAIN LATER IN THE OVERNIGHT. OVERNIGHT LOWS
WILL RANGE FROM THE UPPER 30S NW TO UPPER 40S SE.
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 300 AM WEDNESDAY...
CLOSED LOW OVER AND ASSOCIATED UPPER TROUGH WILL SLOWLY EXIT THE NEW
ENGLAND AND THE NORTHEAST ON THURSDAY. ATTENDANT SFC COLD FRONT AND
ACCOMPANYING BAND OF CONVECTION WILL BE WELL OFFSHORE BY DAYBREAK
THURSDAY AS POST-FRONTAL COLD DRY AIR ADVECTION WILL SUPPORT TEMPS A
FEW DEGREES BELOW NORMAL ON THURSDAY. CONTINUED SWLY FLOW ALOFT MAY
SUPPORT A FAIRLY EXTENSIVE CANOPY OF HIGH CLOUDS WELL INTO THE
AFTERNOON...MAINLY ACROSS EASTERN NC. ADDITIONALLY...STRONG/TIGHT
PRESSURE GRADIENT TO START THE DAY WILL QUICKLY RELAX BY THE EARLY
AFTERNOON. THUS EXPECT TO SEE THE STRONGEST NWLY WIND GUSTS BY
LUNCHTIME...IN THE 22 TO 25KT RANGE...DIMINISHING INTO THE TEENS BY
THE AFTERNOON.
HIGHS RANGING FROM LOWER 50S NORTH TO MID/UPPER 50S SOUTH. LOWS
THURSDAY NIGHT IN THE UPPER 20S TO LOWER 30S.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 AM WEDNESDAY...
SPLIT FLOW PATTERN WILL PREVAIL OVER THE WEEKEND AND INTO EARLY NEXT
WEEK. A SERIES OF VIGOROUS MOISTURE STARVED SHORTWAVE TROUGHS WILL
TRAVERSE THE REGION FRIDAY AND THROUGH THE WEEKEND. ASIDE FROM SOME
POSSIBLE THIN HIGH CLOUDS...EXPECT LITTLE TO NO SENSIBLE WEATHER
IMPACTS WITH A STRENGTHENING +1035MB SURFACE HIGH MAINTAINING A DRY
WEATHER CONDITIONS ACROSS THE CAROLINAS THROUGH SUNDAY.
MEDIUM RANGE MODELS ARE IN SURPRISING GOOD AGREEMENT WITH THE
EVOLUTION OF A CLOSED UPPER LOW DEVELOPING ACROSS THE MIDDLE MS
VALLEY ON SUNDAY...WITH A CONTINUED EASTWARD PROGRESSION INTO THE
SOUTHERN APPALACHIANS ON MONDAY AND INTO THE MID-ATLANTIC STATES ON
TUESDAY. CIRRUS IN ADVANCE OF THIS SYSTEM WILL BEGIN TO OVERSPREAD
THE AREA AS EARLY AS SUNDAY WITH INCREASING RAIN CHANCES BY MONDAY
AFTERNOON THROUGH EARLY TUESDAY. WAY TOO EARLY TO GET TOO DETAILED
BUT WILL MONITOR EVOLUTION OVER THE NEXT SEVERAL DAYS AS CURRENT
SYNOPTIC PATTERN COULD FAVOR SOME HIGH IMPACT WEATHER FOR CENTRAL
NC(HEAVY RAIN, LOW CAPE/HIGH SHEAR SEVERE WX).
EXPECT SLIGHTLY BELOW NORMAL TEMPERATURES TO CLOSE THE WORK WEEK
WITH TEMPERATURES MODERATING TO NEAR OR SLIGHTLY ABOVE NORMAL BY
EARLY NEXT WEEK.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 1255 PM WEDNESDAY...
SUB-VFR CONDITIONS...A COMBINATION OF MVFR AND IFR ESPECIALLY IN
TERMS OF CEILINGS...WILL IMPROVE TO WIDESPREAD VFR FROM WEST TO EAST
TONIGHT. NUMEROUS TO WIDESPREAD SHOWERS WILL DIMINISH FOLLOWING A
COLD FRONT...WITH THE THREAT OF EVEN AN ISOLATED SHOWER ABOUT ENDED
IN THE IMMEDIATE TRIAD BY 02Z...AND IN ALL OF CENTRAL NORTH CAROLINA
AGAIN BY 09Z. BY 12Z THURSDAY...AND LIKELY BY 09Z THURSDAY...VFR
CONDITIONS SHOULD PREVAIL ACROSS CENTRAL NORTH CAROLINA. SOME
GUIDANCE SUGGESTS THE POTENTIAL FOR RENEWED LOWER VISIBILITIES THIS
EVENING ESPECIALLY IN THE COASTAL PLAIN PRIOR TO COLD FRONTAL
PASSAGE. THERE ARE LOWER VISIBILITIES FOR A PERIOD THIS EVENING IN
THE FORECASTS FOR KRWI AND KFAY AS A RESULT.
IN THE WAKE OF THE COLD FRONT MOVING THROUGH CENTRAL NORTH CAROLINA
SURFACE WINDS VEER TO NORTHWEST-TO-NORTH. A RELATIVELY TIGHT SURFACE
GRADIENT DEVELOPING AS HIGH PRESSURE BUILDS IN WILL RESULT IN SOME
WIND GUSTS WITH MIXING THURSDAY TO THE LOWER 20S KNOTS. AN UPPER JET
OVERHEAD SHOULD HOLD SOME CIRRUS ACROSS MUCH OF CENTRAL NORTH
CAROLINA INTO THURSDAY...AND THAT MAY LIMIT SLIGHTLY MIXING AND WIND
GUST POTENTIAL...WHICH BASED ON THE GFS COULD BE INTO THE UPPER 20S
KNOTS TOWARD KRWI IF VERY GOOD MIXING WOULD BE REALIZED LATE
THURSDAY MORNING.
BEYOND THE 18Z VALID TAF PERIOD...VFR CONDITIONS SHOULD PREVAIL
THROUGH THE WEEKEND. THE NEXT THREAT FOR ADVERSE AVIATION CONDITIONS
WOULD COME BY LATE MONDAY AND MONDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...KS/DJF
NEAR TERM...10/DJF
SHORT TERM...CBL
LONG TERM...CBL
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1021 AM EST WED DEC 2 2015
.SYNOPSIS...A COLD FRONT PUSHES THROUGH THE REGION THIS EVENING.
BEHIND THE FRONT...HIGH PRESSURE BUILDS INTO THE AREA FOR THE
REMAINDER OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1020 AM WEDNESDAY...
ONLY VERY PATCHY DENSE FOG WAS OBSERVED IN CENTRAL NORTH CAROLINA AS
LATE MORNING APPROACHED...SO THE DENSE FOG ADVISORY HAS BEEN ALLOWED
TO EXPIRE. SATELLITE IMAGERY SHOWED GOOD DIFFLUENCE OVER CENTRAL
NORTH CAROLINA AHEAD OF UPPER-LEVEL LOW PRESSURE THAT WILL MOVE OVER
THE WESTERN GREAT LAKES. WEAK MID-LEVEL SHORTWAVES WILL MOVE INTO
CENTRAL NORTH CAROLINA IN THE SOUTHWEST FLOW ALOFT...AS PRECIPITABLE
WATER VALUES INCREASE...EVEN OVER THE COASTAL PLAIN...TO GENERALLY
AROUND 1.5 INCHES THIS AFTERNOON. THE COLD FRONT MOVING INTO THE
MOUNTAINS SHOULD ONLY VERY SLOWLY MOVE EAST...WITH NUMEROUS TO AT
TIMES MORE WIDESPREAD SHOWERS OCCURRING AHEAD OF IT. SHOWERS COULD
BE QUITE SCATTERED FOR A WHILE IN THE COASTAL PLAIN...WHERE
PRECIPITABLE WATER VALUES ON THE SPC MESOANALYSIS ARE NEAR AN INCH
AT BEST AS OF THIS WRITING...AND FARTHEST FROM THE MID- AND UPPER-
LEVEL JET SUPPORT TO THE NORTHWEST OF CENTRAL NORTH CAROLINA. THE
MORE NUMEROUS SHOWERS MAY NOT OCCUR THERE UNTIL LATER THIS AFTERNOON
AND INTO THE OVERNIGHT...AND MAY NEED TO INTRODUCE CATEGORICAL
CHANCES FOR THAT AREA INTO THE EVENING AS THE RAP FORECASTS
PRECIPITABLE WATER VALUES THERE ACTUALLY INCREASING TO OVER 1.5
INCHES BY 00Z OR SO.
700MB TEMPERATURES ARE FORECAST TO COOL ON RAP MODEL SOUNDINGS...BUT
THE TEMPERATURE PROFILE ALOFT WARMS A LITTLE AND THE POTENTIAL FOR
THUNDER SEEMS REMOTE. 0-3KM MLCAPE BASICALLY ONLY REGISTERS NEAR AND
OFFSHORE...COINCIDENT WITH THE SPC OUTLOOK...BUT WITH A SLIGHT
CHANCE OF THUNDER IN THE FORECAST AND MUCAPE BETWEEN ABOUT 100 AND
300J/KG AREAWIDE...WILL CONTINUE THE MENTION OF A SLIGHT CHANCE
AHEAD OF THE FRONT AND AS 700MB TEMPERATURES COOL. WITH THE CLOUDS
AND SHOWERS HIGHS ARE FORECAST ON THE LOW END OF MOS GUIDANCE BUT
LIKE THE TREND FOR NOW THOUGH PARTS OF THE TRIAD IN PARTICULAR COULD
END UP A COUPLE OF DEGREES WARMER WITH KGSO IN THE UPPER 50S ALREADY
AS OF THIS WRITING. OVERNIGHT...THE COLD FRONT SHOULD PROGRESS
THROUGH CENTRAL NC FROM NW TO SE BETWEEN 00Z AND 09Z THURSDAY.
DRYING OCCURS BEHIND THE FRONT...WITH PROBABLY PRETTY LIMITED
CHANCES OF PRECIPITATION IN THE TRIAD BY 02Z...TRIANGLE BY AROUND
05Z...AND THE COASTAL PLAIN LATER IN THE OVERNIGHT. OVERNIGHT LOWS
WILL RANGE FROM THE UPPER 30S NW TO UPPER 40S SE.
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 300 AM WEDNESDAY...
CLOSED LOW OVER AND ASSOCIATED UPPER TROUGH WILL SLOWLY EXIT THE NEW
ENGLAND AND THE NORTHEAST ON THURSDAY. ATTENDANT SFC COLD FRONT AND
ACCOMPANYING BAND OF CONVECTION WILL BE WELL OFFSHORE BY DAYBREAK
THURSDAY AS POST-FRONTAL COLD DRY AIR ADVECTION WILL SUPPORT TEMPS A
FEW DEGREES BELOW NORMAL ON THURSDAY. CONTINUED SWLY FLOW ALOFT MAY
SUPPORT A FAIRLY EXTENSIVE CANOPY OF HIGH CLOUDS WELL INTO THE
AFTERNOON...MAINLY ACROSS EASTERN NC. ADDITIONALLY...STRONG/TIGHT
PRESSURE GRADIENT TO START THE DAY WILL QUICKLY RELAX BY THE EARLY
AFTERNOON. THUS EXPECT TO SEE THE STRONGEST NWLY WIND GUSTS BY
LUNCHTIME...IN THE 22 TO 25KT RANGE...DIMINISHING INTO THE TEENS BY
THE AFTERNOON.
HIGHS RANGING FROM LOWER 50S NORTH TO MID/UPPER 50S SOUTH. LOWS
THURSDAY NIGHT IN THE UPPER 20S TO LOWER 30S.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 AM WEDNESDAY...
SPLIT FLOW PATTERN WILL PREVAIL OVER THE WEEKEND AND INTO EARLY NEXT
WEEK. A SERIES OF VIGOROUS MOISTURE STARVED SHORTWAVE TROUGHS WILL
TRAVERSE THE REGION FRIDAY AND THROUGH THE WEEKEND. ASIDE FROM SOME
POSSIBLE THIN HIGH CLOUDS...EXPECT LITTLE TO NO SENSIBLE WEATHER
IMPACTS WITH A STRENGTHENING +1035MB SURFACE HIGH MAINTAINING A DRY
WEATHER CONDITIONS ACROSS THE CAROLINAS THROUGH SUNDAY.
MEDIUM RANGE MODELS ARE IN SURPRISING GOOD AGREEMENT WITH THE
EVOLUTION OF A CLOSED UPPER LOW DEVELOPING ACROSS THE MIDDLE MS
VALLEY ON SUNDAY...WITH A CONTINUED EASTWARD PROGRESSION INTO THE
SOUTHERN APPALACHIANS ON MONDAY AND INTO THE MID-ATLANTIC STATES ON
TUESDAY. CIRRUS IN ADVANCE OF THIS SYSTEM WILL BEGIN TO OVERSPREAD
THE AREA AS EARLY AS SUNDAY WITH INCREASING RAIN CHANCES BY MONDAY
AFTERNOON THROUGH EARLY TUESDAY. WAY TOO EARLY TO GET TOO DETAILED
BUT WILL MONITOR EVOLUTION OVER THE NEXT SEVERAL DAYS AS CURRENT
SYNOPTIC PATTERN COULD FAVOR SOME HIGH IMPACT WEATHER FOR CENTRAL
NC(HEAVY RAIN, LOW CAPE/HIGH SHEAR SEVERE WX).
EXPECT SLIGHTLY BELOW NORMAL TEMPERATURES TO CLOSE THE WORK WEEK
WITH TEMPERATURES MODERATING TO NEAR OR SLIGHTLY ABOVE NORMAL BY
EARLY NEXT WEEK.
&&
.AVIATION /15Z WEDNESDAY THROUGH MONDAY/...
AS OF 1020 AM WEDNESDAY...
24-HOUR TAF PERIOD: FAIRLY HIGH CONFIDENCE THAT IFR/LIFR CEILINGS
WILL CONTINUE THIS MORNING...WITH MOSTLY VFR AND MVFR VISIBILITIES
AND ONLY VERY PATCHY IFR VISIBILITIES. WINDS WILL INCREASE TO AROUND
10 KTS DURING THE DAY AND BECOME GUSTY DURING THE AFTERNOON AND
EVENING ESPECIALLY EAST OF THE TRIAD AS THE COLD FRONT APPROACHES.
WINDS WILL BE SOUTHWEST AHEAD OF THE FRONT...VEERING TO NNW BEHIND
IT. THE FRONT WILL MOVE THROUGH FROM NW TO SE BETWEEN 00Z AND 09Z
THURSDAY...WITH IMPROVING AVIATION CONDITIONS AND DIMINISHING
CHANCES FOR ANY RAIN FOLLOWING THE FRONT.
LOOKING AHEAD: THE SUB-VFR CONDITIONS WILL IMPROVE TO VFR BEHIND THE
COLD FRONT THAT IS EXPECTED TO MOVE THROUGH TONIGHT (THROUGH MOST OF
CENTRAL NC BY 06-09Z). WINDS MAY BE A BIT BREEZY OUT OF THE NNW
INITIALLY THURSDAY...BUT SHOULD ABATE BY LATE THURSDAY. VFR
CONDITIONS ARE EXPECTED TO PERSIST THROUGH THE WEEKEND AS HIGH
PRESSURE BUILDS INTO THE REGION.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...KS/DJF
NEAR TERM...10/DJF
SHORT TERM...CBL
LONG TERM...CBL
AVIATION...10/DJF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
222 PM CST WED DEC 2 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 222 PM CST WED DEC 2 2015
LATEST SUITE OF SATELLITE IMAGERY SHOWS A CLEAR SKY ACROSS WESTERN
AND CENTRAL NORTH DAKOTA THIS AFTERNOON WITH INCREASING MID/HIGH
CLOUDS (700MB-500MB) NOW INTO CENTRAL MONTANA. WATER VAPOR SHOWS A
SHORTWAVE TROUGH PUSHING THROUGH THE IDAHO PANHANDLE WITH A SURFACE
TROUGH STRETCHING FROM ALBERTA SOUTH INTO WESTERN MONTANA. FOR
TONIGHT...EXPECT A CLEAR SKY IN THE EVENING GIVING WAY TO A PARTLY/MOSTLY
CLOUDY SKY WEST INTO PORTIONS OF WEST CENTRAL NORTH DAKOTA. ALL
MODELS REMAIN DRY WITH THIS SHORTWAVE AND SURFACE TROUGH AS IT
SHIFTS THROUGH 06Z-15Z THURSDAY. WILL MAINTAIN A DRY FORECAST WITH
INCREASING CLOUDS WEST AND PORTIONS OF WEST CENTRAL. THE JAMES
RIVER VALLEY WILL REMAIN CLEAR UNTIL 12Z THURSDAY AND WITH FAIRLY
FRESH SNOW COVER ON THE GROUND...THIS IS THE AREA WHERE RADIATIONAL
COOLING WILL BE MAXIMIZED. OVERNIGHT LOWS IN THE LOWER TEENS JAMES
RIVER VALLEY WITH MID TEENS TO LOWER 20S ELSEWHERE...ESPECIALLY
WEST IN AREAS LACKING SNOW COVER AND ADDITIONAL CLOUDS ARRIVING
OVERNIGHT. LOOKED AT THE POTENTIAL FOR FOG IN THE JAMES RIVER
VALLEY LATE TONIGHT INTO EARLY THURSDAY MORNING. THE HRRR SHOWS
NOTHING DEVELOPING AT THIS TIME. WITH HIGHS IN THE UPPER 20S TO
NEAR 32F WEDNESDAY...FEEL THE BOUNDARY LAYER WILL NOT BE MOIST
ENOUGH TO SUPPORT AREAS OF FOG. OTHERWISE...CLOUDS DECREASING
QUICKLY AFTER SUNRISE /12Z- 15Z/ FOLLOWED BY SUNNY CONDITIONS AND
HIGHS 35 TO 45.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 222 PM CST WED DEC 2 2015
DRY CONDITIONS AND MILD TEMPERATURES HIGHLIGHT THE EXTENDED PERIOD.
AN UPPER LEVEL RIDGE WILL BE LOCATED OVER WESTERN AND CENTRAL NORTH
DAKOTA BY THURSDAY EVENING AND INTO THE OVERNIGHT HOURS...BRINGING
CALM AND DRY CONDITIONS. EXPECT MUCH WARMER TEMPERATURES BY FRIDAY
AFTERNOON...WITH WIDESPREAD HIGHS IN THE LOW TO MID 40S.
BY FRIDAY EVENING AND INTO SATURDAY MORNING...WE WILL TRANSITION
INTO A BRIEF PERIOD OF SOUTHWESTERLY FLOW WITH THE APPROACH OF AN
UPPER LEVEL SHORTWAVE TROUGH AND ASSOCIATED COLD FRONT AT THE
SURFACE. AT THE MOMENT...IT APPEARS THAT ANY PRECIPITATION
ASSOCIATED WITH SAID COLD FRONT WILL BE LIMITED TO NORTH OF THE
CANADIAN BORDER...WHERE THE STRONGER FORCING WILL RESIDE.
A RATHER PROGRESSIVE AND MILD PATTERN WILL CONTINUE THROUGH THE REST
OF THE PERIOD...WITH SUBTLE WAVES MOVING QUICKLY THROUGH THE REGION.
LITTLE IF ANY PRECIPITATION WILL BE POSSIBLE WITH ANY OF THESE
WAVES...AND TEMPERATURES WILL GENERALLY REMAIN ABOVE AVERAGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 222 PM CST WED DEC 2 2015
VFR CIGS/VSBYS EXPECTED THROUGH 18Z THURSDAY. A SURFACE TROUGH
WILL MOVE THROUGH WESTERN AND CENTRAL NORTH DAKOTA WEDNESDAY
NIGHT/EARLY THURSDAY MORNING (06Z-15Z). THIS WILL PRODUCE SCT/BKN
CLOUDS BETWEEN 3500FT AND 15000FT AGL WEST AND INTO PORTIONS OF
SOUTH CENTRAL NORTH DAKOTA. THIS INCLUDES KISN/KDIK/KBIS. HOWEVER
NO PRECIPITATION IS EXPECTED AT THIS TIME. EXPECT A CLEARING SKY
AFTER 15Z THURSDAY ALL TERMINALS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KS
LONG TERM...ZH
AVIATION...KS
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
957 AM EST WED DEC 2 2015
.DISCUSSION...
RAINFALL WILL FINALLY BE COMING TO AN END ACROSS THE AREA THROUGH
THE REST OF THE DAY. THE HRRR APPEARS TO HAVE A GOOD HANDLE ON THE
CURRENT LOCATION OF PRECIP AND ITS MOVEMENT...AND IT SHOWS RAIN
MOVING TO OUR EAST AROUND 20Z. THE CURRENT POP/WX GRIDS ARE CLOSE
TO THIS...SO NO MAJOR CHANGES ARE NEEDED. THE BACK EDGE OF CLOUDS
ARE NEAR BNA AT THE MOMENT...AND PROJECTING THIS FORWARD BRINGS THE
CLEARING TO OUR PLATEAU COUNTIES AFTER 00Z. SKY GRIDS WILL NEED
ADJUSTMENTS BASED ON THE SLOWER EXIT OF CLOUDS. TEMPERATURES APPEAR
ON TRACK SO FAR...AND PROBABLY WILL NOT RISE MUCH GIVEN CLOUD COVER
AND COLD ADVECTION AT 850 MB.
THE FLOOD WATCH FOR CHEROKEE AND CLAY WILL BE MAINTAINED FOR NOW
GIVEN THE ONGOING FLOODING SITUATION THERE.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...FLOOD WATCH UNTIL 7 PM EST THIS EVENING FOR CHEROKEE-CLAY.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1135 PM CST TUE DEC 1 2015
.UPDATE...
PATCHY FOG DEVELOPING OVER STONEWALL COUNTY...SOUTHERN PART OF THE
ROLLING PLAINS...CLOSE TO WHERE BOTH HRRR AND NAM12 INDICATING IT
WOULD BE. DRIER AIR EDGING SOUTHWARD SHOULD DIMINISH PATCHES
MOSTLY BEFORE DAYBREAK. ADDED PATCHY FOG THIS AREA REMAINDER OF
THE NIGHT. RMCQUEEN
&&
.AVIATION...
VFR WITH LIGHT WINDS AND DRY AIR CONTINUING. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 530 PM CST TUE DEC 1 2015/
AVIATION...
VFR AND DRIER. WEAK SURFACE RIDGE SETTLING IN OVERNIGHT WITH
GENERAL LIGHT NORTHWEST SURFACE WINDS. RMCQUEEN
PREV DISCUSSION... /ISSUED 237 PM CST TUE DEC 1 2015/
SHORT TERM...
DRY ZONAL FLOW ALOFT WILL BECOME NWLY TONIGHT AND REMAIN THAT WAY
THROUGH WEDNESDAY. CHANGE IN WIND DIRECTION ALOFT THE RESULT OF A
MODEST SHORT WAVE TROUGH THAT WILL SUPPORT A WEAK COLD FRONTAL
PASSAGE THROUGH THE FCST AREA. CONSEQUENCES OF THE FRONTAL PASSAGE
WILL BE MINIMAL. WILL SEE A SUBTLE CHANGE IN DIRECTION OF SFC WINDS
TOWARD NW AND NORTH. SOME DRY ADVECTION WILL ALLOW FOR LOW TEMPS TO
FALL A BIT FURTHER THAN SEEN THIS MORNING AND WILL EFFECTIVELY
ELIMINATE RISK FOR FOG AGAIN EARLY WEDNESDAY.
LONG TERM...
DRY NORTHWESTERLY FLOW ALOFT WILL STAY IN PLACE FROM THURS TO FRI
BEFORE A SHORTWAVE RIDGE MOVES OVERHEAD AHEAD OF A TROF OVER THE
PACIFIC NORTHWEST. THE TROF WILL AMPLIFY OVER THE WEEKEND AS IT
MOVES ACROSS THE ROCKIES AND WILL DIG TO THE RIO GRANDE. MODELS HAVE
BECOME MORE IN LINE WITH THE EVOLUTION OF THE TROF COMPARED TO RECENT
DAYS WITH BOTH THE GFS AND ECMWF HAVE THE WAVE OPEN WHILE PASSING
THE REGION FAIRLY QUICKLY. ANOTHER DIFFERENCE THE MODELS HAVE DUKED
OUT IS WHETHER OR NOT ENOUGH MOISTURE CAN BE PUMPED IN TO ALLOW
PRECIP TO DEVELOP SUN AS THE BULK OF THE ENERGY FROM THE TROF MOVES
IN TO THE REGION. THE ANSWER IS NO. A SURFACE HIGH ACROSS A LARGE
CHUNK OF THE EASTERN US WILL KEEP SURFACE WINDS OUT OF THE
NORTHEAST ACROSS THE CENTRAL TO EASTERN GULF COAST WHICH WILL PUSH
MOISTURE OUT OF REACH OF THE TROF. DUE TO THIS REASON ANY MENTION OF
PRECIP FOR SUN HAS BEEN REMOVED FROM THE FORECAST. IN RETURN LOWS
BEHIND THE FRONT EARLY SUN MORNING HAVE BEEN DROPPED BY A COUPLE OF
DEGREES DUE TO SURFACE AIR BEING DRIER THAN PREVIOUSLY FORECASTED.
MANY OF THE BIAS CORRECTED MODEL GRIDS AGREE WITH TEMPS BEING COOLER
FOR THIS REASON.
THE FORECAST BECOMES A BIT CLOUDY (NO PUN INTENDED) EARLY NEXT WEEK
AS MEDIUM RANGE GUIDANCE DIVERGES WITH THE EVOLUTION OF THE UPPER
LEVEL FLOW. THE GFS BUILDS A RIDGE INTO THE REGION HELPING TO WARM
TEMPS TO ABOVE SEASONAL AVERAGE WHILE THE ECMWF WISHES TO KEEP
THINGS ON THE COOLER SIDE WITH A TROF PUSHING A RELATIVELY WEAK
FRONT INTO THE REGION. EITHER WAY THE FORECAST INTO MID NEXT WEEK
APPEARS TO REMAIN DRY. GETTING INTO FORBIDDEN TERRITORY...A CHANGE
IN THE SYNOPTIC PATTERN MAY BE COMING BY NEXT WEEKEND AS GUIDANCE
CONTINUES TO SHOW A DEEP TROF IN SOME FASHION EYEING UP THE SOUTH
PLAINS REGION.
ALDRICH
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/99/05
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1113 PM CST TUE DEC 1 2015
.AVIATION...
PATCHY LT RAIN/DRIZZLE ALONG THE IMMEDIATE COAST WILL END BY 09Z
AND SKIES WILL BEGIN TO CLEAR FROM NW TO SE. LIFR CONDS AT 06Z
WILL TRANSITION TO VFR BY 12Z. VFR CONDS EXPECTED THROUGH 06Z
THURSDAY. 43
&&
.PREV DISCUSSION... /ISSUED 859 PM CST TUE DEC 1 2015/
UPDATE...
CURRENT OBSERVATIONS SUPPORT FORECAST REMAINING ON TRACK THIS
EVENING AND OVERNIGHT. WEAK RETURNS CONTINUE IN SW-NE ORIENTED
LOW/MID LEVEL CLOUD DECK PERSISTING ACROSS SERN TX. MAY SEE AN
INCREASE IN COVERAGE OF LIGHT SHOWERS LATER TONIGHT AS SUGGESTED
BY LATEST RAP GUIDANCE SOUTH OF HWY 59. WILL KEEP SLGT CHANCE
WORDING IN PLACE WITH CHANCE WORDING NEAR THE COAST. COLD AIR
ADVECTION AND SOME CLEARING UP NORTH WILL DIP OVERNIGHT LOWS WELL
INTO THE LOWER 40S IN THE NORTHERN COUNTIES.
INCREASING OFFSHORE WINDS OVERNIGHT WILL KEEP CAUTIONARY WORDING
IN PLACE FOR THE NEARSHORE MARINE ZONES...AND WARRANTS SMALL
CRAFT ADVISORY FOR THE OUTER WATERS BEGINNING AROUND 2AM AND
CONTINUING THROUGH THE MORNING.
48
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 43 62 37 60 36 / 10 10 0 0 0
HOUSTON (IAH) 49 62 42 60 37 / 20 10 0 0 0
GALVESTON (GLS) 56 63 50 59 47 / 40 10 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH WEDNESDAY MORNING
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM 2 AM TO NOON CST WEDNESDAY FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...48
AVIATION/MARINE...43
PLEASE SEE THE 06Z AVIATION FORECAST DISCUSSION BELOW.
&&
.AVIATION...
OBSERVATIONS CONTINUE TO SHOW LOW CLOUDS IN PLACE AT BOTH SAT AND
SSF THIS EVENING. THE HRRR FORECAST SOUNDINGS MANAGE TO CAPTURE
THE LOW-LEVEL MOISTURE AND CONTINUE TO INDICATE THE CLOUDS WILL
HANG ON INTO EARLY WEDNESDAY MORNING. FOR NOW...WE/LL CONTINUE
PREVAILING MVFR CIGS AT KSSF UNTIL 10Z...WITH TEMPO MVFR AT KSAT
THROUGH 09Z. ELSEWHERE...VFR SKIES ARE IN STORE OVERNIGHT AS HIGH
CLOUDS CONTINUE TO MOVE IN FROM THE WEST. A COLD FRONT WILL MOVE
THROUGH WEDNESDAY MORNING BRINGING A SLIGHT INCREASE IN NORTHERLY
WINDS TO THE REGION.
&&
.PREV DISCUSSION... /ISSUED 232 PM CST TUE DEC 1 2015/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
QUIET SENSIBLE WEATHER OVER THE NEXT WEEK AS A DRY FRONT MOVES
THROUGH THE REGION OVERNIGHT INTO WEDNESDAY MORNING WITH AMPLE
SUNSHINE EXPECTED WEDNESDAY.
HIGH CLOUDS ARE STREAMING OVER THE REGION FROM THE SOUTHWEST AHEAD
OF A LONGWAVE TROUGH AXIS OVER THE FOUR CORNER REGION PER LATEST
WATER VAPOR AND RAP ANALYSIS. SURFACE OBSERVATIONS THIS AFTERNOON
PLACE A WEAK COLD FRONT/DRYLINE OVER THE PANHANDLE OF TEXAS
CHARACTERIZED WITH LOW TEENS DEWPOINTS TO THE WEST OF THE BOUNDARY
AND 30S/40S DEWPOINTS TO THE EAST. THIS BOUNDARY WILL SHIFT
THROUGH THE ENTIRE REGION WEDNESDAY MORNING TO EARLY AFTERNOON AND
BRING SOME STRONGER NORTH WINDS OF 10-15 MPH. DRIER AIR ALOFT HAS
BEEN ABLE TO PRECEDE THE FRONT AND THIS HAS ACTED TO INCREASE THE
CONDENSATION PRESSURE DEFICITS WITH WEAKER ISENTROPIC UPGLIDE FOR
THE COASTAL PLAINS. WHILE SOME VIRGA WILL BE LIKELY OVERNIGHT
AHEAD OF THE FRONT...THE LOWER LEVELS PER NAM/GFS SOUNDINGS
SUGGEST IT WILL QUITE DIFFICULT FOR PRECIPITATION TO REACH THE
GROUND. HAVE REMOVED AND WEATHER MENTION FOR THE OVERNIGHT PERIOD
AND REDUCED RAIN CHANCES TO ONLY 10% FOR THE COASTAL PLAINS WITH
EVEN LESS VALUES FARTHER WEST.
THE CLEARING OVERNIGHT AND THE DRIER AIR MOVING IN WILL ALLOW FOR
A COOLER MORNING AND HAVE GONE BELOW SUPERBLEND VALUES THAT ARE
MORE IN LINE WITH ENSEMBLE MEANS WHICH LINE UP TOWARDS RAW MAV/MET
MOS. EXPECT A DECENT WARM-UP WEDNESDAY AFTN AS AMPLE SUN COMBINES
WITH THE DRY AIR IN PLACE. HIGHS SHOULD REACH INTO THE LOW TO
UPPER 60S.
LONG TERM (THURSDAY THROUGH TUESDAY)...
CONTINUED QUIET WEATHER CONDITIONS ARE EXPECTED THROUGH AT LEAST
SATURDAY AS CLEAR SKIES AND SLIGHTLY BELOW NORMAL TEMPERATURES
OCCUR. BY SUNDAY INTO NEXT WEEK...ANOTHER COLD FRONT IS EXPECTED
BUT MAY ALSO BE ON THE DRY SIDE WITH ONLY LIMITED RAIN CHANCES.
THURSDAY AND FRIDAY MORNING WILL BE COOLEST OF THE PERIOD WITH
LOCALIZED FREEZING POCKETS OCCURRING IN THE HILL COUNTRY. OTHER
AREAS ARE EXPECTED TO DROP INTO THE MID TO UPPER 30S AS CLEAR
SKIES AND HIGH PRESSURE ALLOWING FOR NEAR CALM WINDS AIDS A GOOD
RADIATIONAL COOLING SET-UP. HIGHS EACH DAY WILL WARM BACK INTO THE
LOW TO MID 60S.
BY LATE WEEK INTO THE WEEKEND...A STRONGER SHORTWAVE TROUGH WILL
SHIFT ACROSS THE CENTRAL AND SOUTHERN PLAINS THAT WILL HELP PUSH
ANOTHER COLD FRONT THROUGH THE REGION BY LATE SUNDAY INTO MONDAY.
PWATS ONLY RECOVER TO 0.5"-0.7" AHEAD OF THE FRONT AND IT WILL BE
QUITE DIFFICULT TO GET ENOUGH MOISTURE SQUEEZED OUT OF THE
ATMOSPHERE FOR RAIN CHANCES. HAVE REDUCED RAIN CHANCES SUNDAY TO
THE 10-15% RANGE GIVEN THE GOOD MODEL CONSENSUS OF LITTLE TO NO
RAIN EXPECTED. THERE WILL BE ANOTHER LIKELY CHANCE OF SOME
FREEZING TEMPERATURES IN THE HILL COUNTRY NEXT TUESDAY MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 44 65 41 61 38 / - - 0 0 0
AUSTIN BERGSTROM INTL AIRPORT 40 65 37 61 34 / - - 0 0 0
NEW BRAUNFELS MUNI AIRPORT 44 65 38 62 36 / - - 0 0 0
BURNET MUNI AIRPORT 40 62 37 60 36 / - 0 0 0 0
DEL RIO INTL AIRPORT 45 68 39 65 38 / - 0 0 0 0
GEORGETOWN MUNI AIRPORT 40 62 37 59 35 / - - 0 0 0
HONDO MUNI AIRPORT 43 67 36 64 35 / - - 0 0 0
SAN MARCOS MUNI AIRPORT 43 64 38 61 36 / - - 0 0 0
LA GRANGE - FAYETTE REGIONAL 46 64 40 61 37 / 10 - 0 0 0
SAN ANTONIO INTL AIRPORT 46 67 38 64 37 / - - 0 0 0
STINSON MUNI AIRPORT 46 66 40 64 38 / - - 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...OAKS
PUBLIC SERVICE/DATA COLLECTION...LH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1250 PM EST WED DEC 2 2015
.SYNOPSIS...
HIGH PRESSURE WEDGED DOWN THE EASTERN SLOPES OF THE APPALACHIANS
WILL GRADUALLY ERODE THIS AFTERNOON AHEAD OF A COLD FRONT
APPROACHING FROM THE WEST. THIS FRONT WILL CROSS THE REGION LATER
TODAY AND PASS OFFSHORE TONIGHT BRINGING AN END TO THE ONGOING
WIDESPREAD RAINFALL. HIGH PRESSURE FOLLOWS THE FRONT RESULTING IN
DRIER WEATHER AND MORE IN THE WAY OF SEASONAL TEMPERATURES INTO
THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 AM EST WEDNESDAY...
FLOOD THREAT CONTINUES INTO EARLY THIS AFTERNOON. UP TO 2 INCHES
OF RAIN HAS FALLEN OVERNIGHT IN WESTERN PORTIONS OF FORECAST AREA.
THIS MORNING A WARM FRONT REMAINS ACROSS NORTH CAROLINA...AND THE
COLD FRONT WITH A WAVE OF LOW PRESSURE IS JUST TO OUR WEST. ALL
THESE FEATURES WILL LIFT NORTHEAST TODAY. AS LOW PRESSURE
LIFTS NORTHEAST TODAY...THE TRAILING SURFACE COLD FRONT WILL SURGE
EAST...AIDED BY THE PIVOTING 5H UPPER SYSTEM CROSSING THE SOUTHERN
GREAT LAKES. LEANED POPS AND FRONTAL TIMING TOWARDS THE HRRR FOR
THIS MORNING INTO THIS AFTERNOON. ADJUSTED LATE MORNING
TEMPERATURES TOWARDS LATEST OBS AND MODEL TRENDS. EVEN THOUGH
TEMPERATURES ARE A CHALLENGE WITH COLD AIR WEDGE AND RAIN...IT
WILL BE MILD THIS AFTERNOON FOR DECEMBER. HIGH TEMPERATURES WILL
RANGE FROM THE LOWER 50S IN THE MOUNTAINS TO THE LOWER 60S IN THE
PIEDMONT. THE COLD FRONT PUSHES ACROSS FORECAST AREA THIS
AFTERNOON. DECENT 85H FRONT WILL CROSS THE FAR WEST BY EARLY THIS
EVENING AND THE REST OF THE REGION OVERNIGHT. IN THE WAKE OF THE
COLD FRONT...GUSTY NORTHWEST WINDS AND RAIN TO SNOW SHOWERS
POSSIBLE IN THE MOUNTAINS OVERNIGHT. A LIGHT COATING OF SNOW MAY
BE POSSIBLE IN THE NORTHWEST UPSLOPE FAVORED LOCATIONS OF
SOUTHEAST WEST VIRGINIA. OVERNIGHT LOW TEMPERATURES WILL VARY FROM
THE UPPER 20S IN THE MOUNTAINS TO AROUND 40 DEGREES IN PIEDMONT.
AS OF 210 AM EST WEDNESDAY...
FLOOD THREAT REMAINS THE OVERALL CONCERN AT LEAST INTO EARLY THIS
AFTERNOON AS STEADY LIGHT TO MODERATE RAINFALL CONTINUES TO LIFT NE
THROUGH THE REGION AHEAD OF LOW PRESSURE THAT WILL PASS TO THE NW THIS
MORNING. ONCE THIS FEATURE WORKS TO THE NORTH...SHOULD SEE THE TRAILING
SURFACE COLD FRONT FINALLY SURGE EAST...AIDED BY THE PIVOTING 5H UPPER
SYSTEM CROSSING THE SOUTHERN GREAT LAKES. SOME SOLUTIONS HAVE SPED UP
THE TIMING OF EXITING THE HEAVIER RAINFALL OVER THE WEST BY MIDDAY AND
OUT EAST A FEW HOURS EARLIER THIS AFTERNOON WHICH MAY BE A BIT QUICK.
QUESTION IS WHETHER OR NOT WILL GET MUCH IN THE WAY OF SHALLOW CONVECTION
WITHIN THE AXIS OF STEADY RAIN AS SO FAR THE WEDGE HAS PRECLUDED
THIS WITH RAINFALL RATES ON THE LOW SIDE. THIS HAS RESULTED IN
ONLY SLOW RISES ON AREA STREAMS EARLY THIS MORNING.
THE LATEST HRRR CONTINUES TO HINT AT PERIODIC CLUSTERS OF HEAVIER
SHOWERS BUT MAINLY ON THE WESTERN SLOPES CLOSER TO THE SURFACE LOW AND
OUT OVER THE SOUTHEAST WHERE GUIDANCE SHOWS SOME INSTABILITY TRYING TO
MAKE A RUN BY MID AFTERNOON. MODELS HAVE ALSO CUT BACK ON THE ADDED QPF
OUTSIDE OF THE SOUTHERN BLUE RIDGE INTO THIS AFTERNOON BUT FOR NOW WILL
KEEP THE WATCH IN PLACE WITH HEAVIEST QPF STILL OVER THE FAR WEST/SW
WHERE ANOTHER 1-2 INCHES REMAINS POSSIBLE THROUGH MIDDAY...WITH
AN INCH OR LESS ELSEWHERE PER THE LATEST ECMWF. GIVEN FASTER
TRENDS ALSO PLAN TO CUT BACK POPS A BIT FASTER AFTER THIS MORNING
OVER THE WEST AND PIEDMONT BEFORE SUNSET. HIGH TEMPS TRICKY WITH
THE WEDGE LINGERING ALONG THE BLUE RIDGE AND TIMING OF PRECIP
EXODUS WHICH COULD ALLOW A QUICK SPIKE IN VALUES BEFORE THE ACTUAL
FRONT CROSSES FROM THE WEST LATER. MOST MOS NEAR OR ABOVE 60 FROM
THE BLUE RIDGE EAST SO BUMPED UP VALUES MOST LOCATIONS INCLUDING
THE FAR WEST WHERE ALREADY IN THE 50S IN SPOTS.
DECENT 85H FRONT WILL CROSS THE FAR WEST BY EARLY THIS EVENING AND THE
REST OF THE REGION OVERNIGHT. THIS SHOULD RESULT IN A QUICK UPTICK IN
COLD ADVECTION INCLUDING GUSTY NW WINDS...AND UPSLOPE DRIVEN RAIN/SNOW
SHOWERS WESTERN SLOPES WHILE AIDING DOWNSLOPE CLEARING OUT EAST. COULD
BE CLOSE TO ADVISORY LEVEL GUSTS NC MOUNTAINS PER STRONG SUBSIDENCE AND
QUICK DROP IN 85H TEMPS BUT GIVEN ONLY 40 KTS AT 85H WILL HOLD JUST
BELOW WITH THE STRONGEST SPEEDS RIGHT NEAR DAYBREAK THU. APPEARS THE
BOUNDARY LAYER WILL COOL ENOUGH TO SUPPORT SNOW SHOWERS/FLURRIES OUT
WEST MAINLY AFTER MIDNIGHT WITH PERHAPS A LIGHT COATING AT ELEVATION
FAR NW DESPITE A WET/WARM GROUND AND GUSTY WINDS. OTRW WILL HAVE
THE TYPICAL SPLIT IN SPILLOVER LOW CLOUDS WEST OF THE BLUE RIDGE
AND CLEAR OUT EAST AFTER MIDNIGHT WITH LOWS MOSTLY 30S EXCEPT ONLY
AROUND 40 PIEDMONT PENDING THE DEGREE OF MIXING.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT/...
AS OF 230 AM EST WEDNESDAY...
THE UPPER LEVEL PATTERN WILL REMAIN PROGRESSIVE WITH TRANSIENT SPLIT
FLOW CHARACTERISTICS THROUGH THE SHORT TERM...AS THE CLOSED LOW OVER
NEW ENGLAND GIVES WAY TO RIDGING OVER THE MID ATLANTIC REGION INTO THE
WEEKEND. THIS WILL ALLOW SURFACE HIGH PRESSURE TO BUILD IN FROM THE
MISSISSIPPI VALLEY AND BRING A FEW DAYS OF FAIR WEATHER TO THE
REGION...SAVE FOR BLUSTERY CONDITIONS ON THURSDAY AND SOME LINGERING
SNOW SHOWERS ALONG THE FAR WESTERN SLOPES OF THE APPALACHIANS THAT WILL
BE DISSIPATING THURSDAY MORNING.
THERE WILL BE A MODERATING TREND IN TEMPERATURES WITH HIGHS STARTING
OUT 5 TO 10 DEGREES BELOW NORMAL ON THURSDAY...THEN RISING TO SEASONAL
LEVELS OF MIDDLE 50S EAST OF THE BLUE RIDGE/UPPER 40S AND LOWER 50S
WEST BY SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 200 PM EST TUESDAY...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE
WEEKEND. A 500MB SHORTWAVE MOVES ACROSS THE SOUTHEAST UNITED STATES
DURING THE PERIOD. HOWEVER...OPERATIONAL AND ENSEMBLE MODELS DIFFER
IN THE INTENSITY AND LOCATION OF THIS FEATURE. THE GFS CUTS OFF THE
LOW OVER THE CENTRAL APPALACHIANS...WHILE THE ECMWF REMAINS AN OPEN
WAVE AND PUSHES IT OUT TO SEA. IN ANY CASE ...THE MOISTURE WITH
THIS FEATURE REMAINS LIMITED...WITH 500MB HEIGHTS RISING IN THE
EAST INTO THE WEEKEND. TEMPERATURES ARE EXPECTED TO BE SLIGHTLY
ABOVE NORMAL THROUGH THE WEEKEND. UNDER HIGH PRESSURE...DRY
WEATHER CONTINUES ON MONDAY WITH TEMPERATURES MODERATING SLIGHTLY
ABOVE NORMAL. MOISTURE INCREASES MONDAY NIGHT ASSOCIATED WITH A
SOUTHERN STREAM SYSTEM. THE NEXT CHANCE FOR ANY DECENT
PRECIPITATION WILL BE TUESDAY WHEN A SYSTEM WILL MOVE UP THE COAST
FROM THE GULF. HIGH UNCERTAINTY AS THIS IS OVER A WEEK AWAY. THE
GFS IS WETTER THAN THE ECMWF. WITH TEMPERATURES BEING ABOVE NORMAL
EARLY NEXT...MOST IF NOT ALL OF THE PRECIPITATION WOULD BE RAIN.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 1248 PM EST WEDNESDAY...
VARIABILITY IN CEILINGS AND VISIBILITIES IN LOW CLOUDS AND RAIN
WILL HINDER AVIATION OPERATIONS DURING THE TAF PERIOD.
IFR AND LIFR CONDITIONS WILL CONTINUE THIS AFTERNOON INTO TONIGHT
ESPECIALLY IN THE EAST. HOWEVER...SOME POCKETS OF VFR/MVFR WILL
OCCUR IN THE WEST WHERE RAIN IS TAPERING OFF.
THERE WILL BE VARIABILITY IN VISIBILITIES BASED ON INTENSITY OF
RAINFALL. TYPICAL FLUCTUATIONS WILL RUN FROM 1 TO 3SM IN MODERATE
RAIN OR WHEN RAIN TAPERS OFF...WHILE CIGS MAY LIFT TOWARD MVFR
AROUND 1-2KFT IF RAIN COMES DOWN HARD ENOUGH TO MIX OUT THE LOW
CIGS SOME. ALSO IFR TO LIFR CONDITIONS WILL OCCUR WHERE RAIN
TAPERS AND FOG REDEVELOPS. IN GENERAL....POOR FLYING CONDITIONS
EXPECTED IN WIDESPREAD RAIN/FOG AND LOWER CIGS.
THE COLD FRONT WILL SLOWLY MOVE EAST ACROSS THE REGION THIS
AFTERNOON INTO TONIGHT. THE WEDGE ALONG THE BLUE RIDGE WILL
SLOWLY MIX OUT OR ERODE THIS AFTERNOON...SUCH THAT MOST PLACES
WILL SEE CIGS IN MVFR WITH MVFR/IFR VSBYS WITH RAIN SHOWERS.
THE SHOWERS SHOULD BE EAST OF KBLF/KLWB/KBCB NEXT HOUR OR TWO
AND KROA BY 20Z...LINGERING AT LYH/DAN TIL 22Z. WINDS HAVE ALREADY
SHIFTED TO THE WEST AT KBLF/KLWB AND GUSTS UP 20 KTS MAY BE
POSSIBLE AT THIS TIME.
BEHIND THE FRONT EXPECTING UPSLOPE MVFR CIGS TO REDEVELOP AFTER
PERHAPS A PERIOD OF BRIEF VFR BEHIND THE FRONT THIS EVENING. ALSO
A FEW RAIN OR SNOW SHOWERS MAY OCCUR FROM KBLF TO KLWB BUT GIVEN
ISOLATED NATURE WONT INCLUDE ANY VSBYS REDUCTIONS OVERNIGHT. OTRW
APPEARS MVFR TO LOW END VFR CIGS WILL SNEAK BACK INTO KBCB/KROA
AFTER MIDNIGHT WHEN NW WINDS MAY GUST TO 25 OR 30 KTS ALONG THE
RIDGES. DOWNSLOPING SHOULD KEEP EASTERN SITES VFR OVERNIGHT WITH
WINDS GENERALLY BELOW 10 KTS BEHIND THE FRONT.
SOME MVFR/OCNL IFR CIGS IN THE UPSLOPE AREAS AT KBLF AND KLWB
WILL LINGER INTO EARLY THURSDAY MORNING BEHIND FRONT...ALONG WITH
SCATTERED RAIN AND SNOW SHOWERS.
MEDIUM CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE
PERIOD.
.EXTENDED AVIATION DISCUSSION...
HIGH PRESSURE AND VFR CONDITIONS SHOULD DOMINATE THURSDAY NIGHT THROUGH
THE WEEKEND...HOWEVER PATCHY EARLY MORNING VALLEY FOG MAY PRODUCE
SOME BRIEF IFR CONDITIONS FRI AND SAT MORNING DUE TO MOIST GROUND
CONDITIONS FROM RECENT RAINFALL.
&&
.HYDROLOGY...
AS OF 1250 PM EST WEDNESDAY...
FLOOD WATCH REMAINS IN PLACE WITH FEW ADDITIONS GIVEN OVERALL SLOW
RAINFALL RATES AND LESS COVERAGE IN THE SOUTHEAST. WITH PWATS
200-300 PERCENT OF NORMAL...THE RAINFALL EFFICIENCY SHOULD BE HIGH
THROUGH THIS MORNING WEST AND EAST INTO THE AFTERNOON WITH
PERHAPS SOME SHALLOW CONVECTION MIXING IN AS THE FRONT APPROACHES
AROUND MIDDAY.
FLOOD WARNINGS ARE IN EFFECT FOR WATAGUA...ASHE AND GRAYSON
COUNTIES UNTIL 2 PM.
THE BEST POTENTIAL FOR SMALL STREAM FLOODING REMAINS OVER THE
WEST INTO EARLY THIS AFTERNOON...MAINLY ALONG THE SOUTHERN BLUE
RIDGE AND MOUNTAIN EMPIRE REGION WITH HEAVIER RAINFALL MOVING UP
THE WESTERN SLOPES BEFORE HEADING EAST LATER THIS MORNING.
WILL HAVE TO WATCH MAIN STEM RIVERS AND THE HEADWATERS...LIKE
UPPER ROANOKE AND DAN RIVER. PRESENTLY...THE DAN RIVER FROM
DANVILLE...DOWNSTREAM TO SOUTH BOSTON IS FAVORED TO GO TO NEAR
FLOOD STAGE BY THURSDAY MORNING...IF THE RAINFALL OF ANOTHER INCH
OR SO PANS OUT THROUGH LATER TODAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLOOD WATCH UNTIL 7 PM EST THIS EVENING FOR VAZ007-009-010-
012>017-022>024-032>035-045>047.
NC...FLOOD WATCH UNTIL 7 PM EST THIS EVENING FOR NCZ001>004-018>020.
WV...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/KK
SHORT TERM...MBS
LONG TERM...KK/MBS
AVIATION...JH/KK
HYDROLOGY...JH/KK/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
949 AM EST WED DEC 2 2015
.SYNOPSIS...
HIGH PRESSURE WEDGED DOWN THE EASTERN SLOPES OF THE APPALACHIANS
WILL GRADUALLY ERODE THIS MORNING AHEAD OF A COLD FRONT APPROACHING
FROM THE WEST. THIS FRONT WILL CROSS THE REGION LATER TODAY AND
PASS OFFSHORE TONIGHT BRINGING AN END TO THE ONGOING WIDESPREAD
RAINFALL. HIGH PRESSURE FOLLOWS THE FRONT RESULTING IN DRIER WEATHER
AND MORE IN THE WAY OF SEASONAL TEMPERATURES INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 AM EST WEDNESDAY...
FLOOD THREAT CONTINUES INTO EARLY THIS AFTERNOON. UP TO 2 INCHES
OF RAIN HAS FALLEN OVERNIGHT IN WESTERN PORTIONS OF FORECAST AREA.
THIS MORNING A WARM FRONT REMAINS ACROSS NORTH CAROLINA...AND THE
COLD FRONT WITH A WAVE OF LOW PRESSURE IS JUST TO OUR WEST. ALL
THESE FEATURES WILL LIFT NORTHEAST TODAY. AS LOW PRESSURE
LIFTS NORTHEAST TODAY...THE TRAILING SURFACE COLD FRONT WILL SURGE
EAST...AIDED BY THE PIVOTING 5H UPPER SYSTEM CROSSING THE SOUTHERN
GREAT LAKES. LEANED POPS AND FRONTAL TIMING TOWARDS THE HRRR FOR
THIS MORNING INTO THIS AFTERNOON. ADJUSTED LATE MORNING
TEMPERATURES TOWARDS LATEST OBS AND MODEL TRENDS. EVEN THOUGH
TEMPERATURES ARE A CHALLENGE WITH COLD AIR WEDGE AND RAIN...IT
WILL BE MILD THIS AFTERNOON FOR DECEMBER. HIGH TEMPERATURES WILL
RANGE FROM THE LOWER 50S IN THE MOUNTAINS TO THE LOWER 60S IN THE
PIEDMONT. THE COLD FRONT PUSHES ACROSS FORECAST AREA THIS
AFTERNOON. DECENT 85H FRONT WILL CROSS THE FAR WEST BY EARLY THIS
EVENING AND THE REST OF THE REGION OVERNIGHT. IN THE WAKE OF THE
COLD FRONT...GUSTY NORTHWEST WINDS AND RAIN TO SNOW SHOWERS
POSSIBLE IN THE MOUNTAINS OVERNIGHT. A LIGHT COATING OF SNOW MAY
BE POSSIBLE IN THE NORTHWEST UPSLOPE FAVORED LOCATIONS OF
SOUTHEAST WEST VIRGINIA. OVERNIGHT LOW TEMPERATURES WILL VARY FROM
THE UPPER 20S IN THE MOUNTAINS TO AROUND 40 DEGREES IN PIEDMONT.
AS OF 210 AM EST WEDNESDAY...
FLOOD THREAT REMAINS THE OVERALL CONCERN AT LEAST INTO EARLY THIS
AFTERNOON AS STEADY LIGHT TO MODERATE RAINFALL CONTINUES TO LIFT NE
THROUGH THE REGION AHEAD OF LOW PRESSURE THAT WILL PASS TO THE NW THIS
MORNING. ONCE THIS FEATURE WORKS TO THE NORTH...SHOULD SEE THE TRAILING
SURFACE COLD FRONT FINALLY SURGE EAST...AIDED BY THE PIVOTING 5H UPPER
SYSTEM CROSSING THE SOUTHERN GREAT LAKES. SOME SOLUTIONS HAVE SPED UP
THE TIMING OF EXITING THE HEAVIER RAINFALL OVER THE WEST BY MIDDAY AND
OUT EAST A FEW HOURS EARLIER THIS AFTERNOON WHICH MAY BE A BIT QUICK.
QUESTION IS WHETHER OR NOT WILL GET MUCH IN THE WAY OF SHALLOW CONVECTION
WITHIN THE AXIS OF STEADY RAIN AS SO FAR THE WEDGE HAS PRECLUDED
THIS WITH RAINFALL RATES ON THE LOW SIDE. THIS HAS RESULTED IN
ONLY SLOW RISES ON AREA STREAMS EARLY THIS MORNING.
THE LATEST HRRR CONTINUES TO HINT AT PERIODIC CLUSTERS OF HEAVIER
SHOWERS BUT MAINLY ON THE WESTERN SLOPES CLOSER TO THE SURFACE LOW AND
OUT OVER THE SOUTHEAST WHERE GUIDANCE SHOWS SOME INSTABILITY TRYING TO
MAKE A RUN BY MID AFTERNOON. MODELS HAVE ALSO CUT BACK ON THE ADDED QPF
OUTSIDE OF THE SOUTHERN BLUE RIDGE INTO THIS AFTERNOON BUT FOR NOW WILL
KEEP THE WATCH IN PLACE WITH HEAVIEST QPF STILL OVER THE FAR WEST/SW
WHERE ANOTHER 1-2 INCHES REMAINS POSSIBLE THROUGH MIDDAY...WITH
AN INCH OR LESS ELSEWHERE PER THE LATEST ECMWF. GIVEN FASTER
TRENDS ALSO PLAN TO CUT BACK POPS A BIT FASTER AFTER THIS MORNING
OVER THE WEST AND PIEDMONT BEFORE SUNSET. HIGH TEMPS TRICKY WITH
THE WEDGE LINGERING ALONG THE BLUE RIDGE AND TIMING OF PRECIP
EXODUS WHICH COULD ALLOW A QUICK SPIKE IN VALUES BEFORE THE ACTUAL
FRONT CROSSES FROM THE WEST LATER. MOST MOS NEAR OR ABOVE 60 FROM
THE BLUE RIDGE EAST SO BUMPED UP VALUES MOST LOCATIONS INCLUDING
THE FAR WEST WHERE ALREADY IN THE 50S IN SPOTS.
DECENT 85H FRONT WILL CROSS THE FAR WEST BY EARLY THIS EVENING AND THE
REST OF THE REGION OVERNIGHT. THIS SHOULD RESULT IN A QUICK UPTICK IN
COLD ADVECTION INCLUDING GUSTY NW WINDS...AND UPSLOPE DRIVEN RAIN/SNOW
SHOWERS WESTERN SLOPES WHILE AIDING DOWNSLOPE CLEARING OUT EAST. COULD
BE CLOSE TO ADVISORY LEVEL GUSTS NC MOUNTAINS PER STRONG SUBSIDENCE AND
QUICK DROP IN 85H TEMPS BUT GIVEN ONLY 40 KTS AT 85H WILL HOLD JUST
BELOW WITH THE STRONGEST SPEEDS RIGHT NEAR DAYBREAK THU. APPEARS THE
BOUNDARY LAYER WILL COOL ENOUGH TO SUPPORT SNOW SHOWERS/FLURRIES OUT
WEST MAINLY AFTER MIDNIGHT WITH PERHAPS A LIGHT COATING AT ELEVATION
FAR NW DESPITE A WET/WARM GROUND AND GUSTY WINDS. OTRW WILL HAVE
THE TYPICAL SPLIT IN SPILLOVER LOW CLOUDS WEST OF THE BLUE RIDGE
AND CLEAR OUT EAST AFTER MIDNIGHT WITH LOWS MOSTLY 30S EXCEPT ONLY
AROUND 40 PIEDMONT PENDING THE DEGREE OF MIXING.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT/...
AS OF 230 AM EST WEDNESDAY...
THE UPPER LEVEL PATTERN WILL REMAIN PROGRESSIVE WITH TRANSIENT SPLIT
FLOW CHARACTERISTICS THROUGH THE SHORT TERM...AS THE CLOSED LOW OVER
NEW ENGLAND GIVES WAY TO RIDGING OVER THE MID ATLANTIC REGION INTO THE
WEEKEND. THIS WILL ALLOW SURFACE HIGH PRESSURE TO BUILD IN FROM THE
MISSISSIPPI VALLEY AND BRING A FEW DAYS OF FAIR WEATHER TO THE
REGION...SAVE FOR BLUSTERY CONDITIONS ON THURSDAY AND SOME LINGERING
SNOW SHOWERS ALONG THE FAR WESTERN SLOPES OF THE APPALACHIANS THAT WILL
BE DISSIPATING THURSDAY MORNING.
THERE WILL BE A MODERATING TREND IN TEMPERATURES WITH HIGHS STARTING
OUT 5 TO 10 DEGREES BELOW NORMAL ON THURSDAY...THEN RISING TO SEASONAL
LEVELS OF MIDDLE 50S EAST OF THE BLUE RIDGE/UPPER 40S AND LOWER 50S
WEST BY SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 200 PM EST TUESDAY...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE
WEEKEND. A 500MB SHORTWAVE MOVES ACROSS THE SOUTHEAST UNITED STATES
DURING THE PERIOD. HOWEVER...OPERATIONAL AND ENSEMBLE MODELS DIFFER
IN THE INTENSITY AND LOCATION OF THIS FEATURE. THE GFS CUTS OFF THE
LOW OVER THE CENTRAL APPALACHIANS...WHILE THE ECMWF REMAINS AN OPEN
WAVE AND PUSHES IT OUT TO SEA. IN ANY CASE ...THE MOISTURE WITH
THIS FEATURE REMAINS LIMITED...WITH 500MB HEIGHTS RISING IN THE
EAST INTO THE WEEKEND. TEMPERATURES ARE EXPECTED TO BE SLIGHTLY
ABOVE NORMAL THROUGH THE WEEKEND. UNDER HIGH PRESSURE...DRY
WEATHER CONTINUES ON MONDAY WITH TEMPERATURES MODERATING SLIGHTLY
ABOVE NORMAL. MOISTURE INCREASES MONDAY NIGHT ASSOCIATED WITH A
SOUTHERN STREAM SYSTEM. THE NEXT CHANCE FOR ANY DECENT
PRECIPITATION WILL BE TUESDAY WHEN A SYSTEM WILL MOVE UP THE COAST
FROM THE GULF. HIGH UNCERTAINTY AS THIS IS OVER A WEEK AWAY. THE
GFS IS WETTER THAN THE ECMWF. WITH TEMPERATURES BEING ABOVE NORMAL
EARLY NEXT...MOST IF NOT ALL OF THE PRECIPITATION WOULD BE RAIN.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
AS OF 550 AM EST WEDNESDAY...
MAINLY IFR OR WORSE EXPECTED TO PREVAIL THIS MORNING...THOUGH
SOME POCKETS OF VFR/MVFR WILL OCCUR ESPCLY AROUND KBLF/KLWB WHERE
MORE IN THE WAY OF LIGHT RAIN OUT OF MID DECK OR HIGH BASED
STRATO-CU WILL OCCUR. SW WINDS WILL ALSO BE STRONG AROUND KBLF
THIS MORNING WITH GUSTS TO 30 KTS POSSIBLE.
THERE WILL BE VARIABILITY IN VSBYS BASED ON INTENSITY OF RAINFALL.
TYPICAL FLUCTUATIONS WILL RUN FROM 1/4 TO 3SM IN MODERATE RAIN OR
WHEN RAIN TAPERS OFF...WHILE CIGS MAY LIFT TOWARD MVFR AROUND
1-2KFT IF RAIN COMES DOWN HARD ENOUGH TO MIX OUT THE LOW CIGS
SOME. ALSO IFR TO LIFR WILL OCCUR WHERE RAIN TAPERS AND FOG
REDEVELOPS THROUGH MIDDAY. OTRW LOOKING AT POOR FLYING CONDITIONS
IN WIDESPREAD RAIN/FOG AND LOWER CIGS THIS MORNING.
AS THE FRONT APPROACHES WINDS START TO SHIFT AROUND TO THE
SOUTHWEST ALLOWING THE WEDGE ALONG THE BLUE RIDGE TO SLOWLY MIX
OUT. THE WEDGE SHOULD ERODE BY AFTERNOON...SUCH THAT MOST PLACES
WILL SEE CIGS IN MVFR WITH MVFR/IFR VSBYS WITH RAIN SHOWERS.
MODELS HAVE SPED UP THE TIMING OF DRYING IN THE WEST. THE SHOWERS
SHOULD BE EAST OF KBLF/KLWB/KBCB...17-19Z...AND KROA BY
20Z...LINGERING AT LYH/DAN TIL 22Z. WINDS WILL START TO SHIFT TO
THE WEST AT KBLF/KLWB LATE AND GUSTS TO 20 KTS CAN BE EXPECTED AT
LEAST AT KBLF DURING THIS TIME.
BEHIND THE FRONT EXPECTING UPSLOPE MVFR CIGS TO REDEVELOP AFTER
PERHAPS A PERIOD OF BRIEF VFR BEHIND THE FRONT THIS EVENING. ALSO
A FEW RAIN OR SNOW SHOWERS MAY OCCUR FROM KBLF TO KLWB BUT GIVEN
ISOLATED NATURE WONT INCLUDE ANY VSBYS REDUCTIONS OVERNIGHT. OTRW
APPEARS MVFR TO LOW END VFR CIGS WILL SNEAK BACK INTO KBCB/KROA
AFTER MIDNIGHT WHEN NW WINDS MAY GUST TO 25 OR 30 KTS ALONG THE
RIDGES. DOWNSLOPING SHOULD KEEP EASTERN SITES VFR OVERNIGHT WITH
WINDS GENERALLY BELOW 10 KTS BEHIND THE FRONT.
.EXTENDED AVIATION DISCUSSION...
SOME MVFR/OCNL IFR CIGS IN THE UPSLOPE AREAS AT KBLF AND KLWB
WILL LINGER INTO EARLY THURSDAY MORNING BEHIND FRONT...ALONG WITH
SCATTERED RAIN AND SNOW SHOWERS.
HIGH PRESSURE AND VFR CONDITIONS SHOULD DOMINATE THURSDAY NIGHT THROUGH
THE WEEKEND...HOWEVER PATCHY EARLY MORNING VALLEY FOG MAY PRODUCE
SOME BRIEF IFR CONDITIONS FRI AND SAT MORNING DUE TO MOIST GROUND
CONDITIONS FROM RECENT RAINFALL.
&&
.HYDROLOGY...
AS OF 949 AM EST WEDNESDAY...
FLOOD WATCH REMAINS IN PLACE WITH FEW ADDITIONS GIVEN OVERALL SLOW
RAINFALL RATES AND LESS COVERAGE IN THE SOUTHEAST. WITH PWATS
200-300 PERCENT OF NORMAL...THE RAINFALL EFFICIENCY SHOULD BE HIGH
THROUGH THIS MORNING WEST AND EAST INTO THE AFTERNOON WITH
PERHAPS SOME SHALLOW CONVECTION MIXING IN AS THE FRONT APPROACHES
AROUND MIDDAY.
FLOOD WARNINGS ARE IN EFFECT FOR WATAGUA...ASHE AND GRAYSON
COUNTIES UNTIL 11 AM.
THE BEST POTENTIAL FOR SMALL STREAM FLOODING REMAINS OVER THE
WEST INTO EARLY THIS AFTERNOON...MAINLY ALONG THE SOUTHERN BLUE
RIDGE AND MOUNTAIN EMPIRE REGION WITH HEAVIER RAINFALL MOVING UP
THE WESTERN SLOPES BEFORE HEADING EAST LATER THIS MORNING.
WILL HAVE TO WATCH MAIN STEM RIVERS AND THE HEADWATERS...LIKE
UPPER ROANOKE AND DAN RIVER. PRESENTLY...THE DAN RIVER FROM
DANVILLE...DOWNSTREAM TO SOUTH BOSTON IS FAVORED TO GO TO NEAR
FLOOD STAGE BY THURSDAY MORNING...IF THE RAINFALL OF ANOTHER INCH
OR SO PANS OUT THROUGH LATER TODAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLOOD WATCH UNTIL 7 PM EST THIS EVENING FOR VAZ007-009-010-
012>017-022>024-032>035-045>047.
NC...FLOOD WATCH UNTIL 7 PM EST THIS EVENING FOR NCZ001>004-018>020.
WV...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/KK
SHORT TERM...MBS
LONG TERM...KK/MBS
AVIATION...AMS/JH/WP
HYDROLOGY...JH/KK/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
607 AM EST WED DEC 2 2015
.SYNOPSIS...
HIGH PRESSURE WEDGED DOWN THE EASTERN SLOPES OF THE APPALACHIANS
WILL GRADUALLY ERODE THIS MORNING AHEAD OF A COLD FRONT APPROACHING
FROM THE WEST. THIS FRONT WILL CROSS THE REGION LATER TODAY AND
PASS OFFSHORE TONIGHT BRINGING AN END TO THE ONGOING WIDESPREAD
RAINFALL. HIGH PRESSURE FOLLOWS THE FRONT RESULTING IN DRIER WEATHER
AND MORE IN THE WAY OF SEASONAL TEMPERATURES INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 210 AM EST WEDNESDAY...
FLOOD THREAT REMAINS THE OVERALL CONCERN AT LEAST INTO EARLY THIS
AFTERNOON AS STEADY LIGHT TO MODERATE RAINFALL CONTINUES TO LIFT NE
THROUGH THE REGION AHEAD OF LOW PRESSURE THAT WILL PASS TO THE NW THIS
MORNING. ONCE THIS FEATURE WORKS TO THE NORTH...SHOULD SEE THE TRAILING
SURFACE COLD FRONT FINALLY SURGE EAST...AIDED BY THE PIVOTING 5H UPPER
SYSTEM CROSSING THE SOUTHERN GREAT LAKES. SOME SOLUTIONS HAVE SPED UP
THE TIMING OF EXITING THE HEAVIER RAINFALL OVER THE WEST BY MIDDAY AND
OUT EAST A FEW HOURS EARLIER THIS AFTERNOON WHICH MAY BE A BIT QUICK.
QUESTION IS WHETHER OR NOT WILL GET MUCH IN THE WAY OF SHALLOW CONVECTION
WITHIN THE AXIS OF STEADY RAIN AS SO FAR THE WEDGE HAS PRECLUDED
THIS WITH RAINFALL RATES ON THE LOW SIDE. THIS HAS RESULTED IN
ONLY SLOW RISES ON AREA STREAMS EARLY THIS MORNING.
THE LATEST HRRR CONTINUES TO HINT AT PERIODIC CLUSTERS OF HEAVIER
SHOWERS BUT MAINLY ON THE WESTERN SLOPES CLOSER TO THE SURFACE LOW AND
OUT OVER THE SOUTHEAST WHERE GUIDANCE SHOWS SOME INSTABILITY TRYING TO
MAKE A RUN BY MID AFTERNOON. MODELS HAVE ALSO CUT BACK ON THE ADDED QPF
OUTSIDE OF THE SOUTHERN BLUE RIDGE INTO THIS AFTERNOON BUT FOR NOW WILL
KEEP THE WATCH IN PLACE WITH HEAVIEST QPF STILL OVER THE FAR WEST/SW
WHERE ANOTHER 1-2 INCHES REMAINS POSSIBLE THROUGH MIDDAY...WITH
AN INCH OR LESS ELSEWHERE PER THE LATEST ECMWF. GIVEN FASTER
TRENDS ALSO PLAN TO CUT BACK POPS A BIT FASTER AFTER THIS MORNING
OVER THE WEST AND PIEDMONT BEFORE SUNSET. HIGH TEMPS TRICKY WITH
THE WEDGE LINGERING ALONG THE BLUE RIDGE AND TIMING OF PRECIP
EXODUS WHICH COULD ALLOW A QUICK SPIKE IN VALUES BEFORE THE ACTUAL
FRONT CROSSES FROM THE WEST LATER. MOST MOS NEAR OR ABOVE 60 FROM
THE BLUE RIDGE EAST SO BUMPED UP VALUES MOST LOCATIONS INCLUDING
THE FAR WEST WHERE ALREADY IN THE 50S IN SPOTS.
DECENT 85H FRONT WILL CROSS THE FAR WEST BY EARLY THIS EVENING AND THE
REST OF THE REGION OVERNIGHT. THIS SHOULD RESULT IN A QUICK UPTICK IN
COLD ADVECTION INCLUDING GUSTY NW WINDS...AND UPSLOPE DRIVEN RAIN/SNOW
SHOWERS WESTERN SLOPES WHILE AIDING DOWNSLOPE CLEARING OUT EAST. COULD
BE CLOSE TO ADVISORY LEVEL GUSTS NC MOUNTAINS PER STRONG SUBSIDENCE AND
QUICK DROP IN 85H TEMPS BUT GIVEN ONLY 40 KTS AT 85H WILL HOLD JUST
BELOW WITH THE STRONGEST SPEEDS RIGHT NEAR DAYBREAK THU. APPEARS THE
BOUNDARY LAYER WILL COOL ENOUGH TO SUPPORT SNOW SHOWERS/FLURRIES OUT
WEST MAINLY AFTER MIDNIGHT WITH PERHAPS A LIGHT COATING AT ELEVATION
FAR NW DESPITE A WET/WARM GROUND AND GUSTY WINDS. OTRW WILL HAVE
THE TYPICAL SPLIT IN SPILLOVER LOW CLOUDS WEST OF THE BLUE RIDGE
AND CLEAR OUT EAST AFTER MIDNIGHT WITH LOWS MOSTLY 30S EXCEPT ONLY
AROUND 40 PIEDMONT PENDING THE DEGREE OF MIXING.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT/...
AS OF 230 AM EST WEDNESDAY...
THE UPPER LEVEL PATTERN WILL REMAIN PROGRESSIVE WITH TRANSIENT SPLIT
FLOW CHARACTERISTICS THROUGH THE SHORT TERM...AS THE CLOSED LOW OVER
NEW ENGLAND GIVES WAY TO RIDGING OVER THE MID ATLANTIC REGION INTO THE
WEEKEND. THIS WILL ALLOW SURFACE HIGH PRESSURE TO BUILD IN FROM THE
MISSISSIPPI VALLEY AND BRING A FEW DAYS OF FAIR WEATHER TO THE
REGION...SAVE FOR BLUSTERY CONDITIONS ON THURSDAY AND SOME LINGERING
SNOW SHOWERS ALONG THE FAR WESTERN SLOPES OF THE APPALACHIANS THAT WILL
BE DISSIPATING THURSDAY MORNING.
THERE WILL BE A MODERATING TREND IN TEMPERATURES WITH HIGHS STARTING
OUT 5 TO 10 DEGREES BELOW NORMAL ON THURSDAY...THEN RISING TO SEASONAL
LEVELS OF MIDDLE 50S EAST OF THE BLUE RIDGE/UPPER 40S AND LOWER 50S
WEST BY SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 200 PM EST TUESDAY...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE
WEEKEND. A 500MB SHORTWAVE MOVES ACROSS THE SOUTHEAST UNITED STATES
DURING THE PERIOD. HOWEVER...OPERATIONAL AND ENSEMBLE MODELS DIFFER
IN THE INTENSITY AND LOCATION OF THIS FEATURE. THE GFS CUTS OFF THE
LOW OVER THE CENTRAL APPALACHIANS...WHILE THE ECMWF REMAINS AN OPEN
WAVE AND PUSHES IT OUT TO SEA. IN ANY CASE ...THE MOISTURE WITH
THIS FEATURE REMAINS LIMITED...WITH 500MB HEIGHTS RISING IN THE
EAST INTO THE WEEKEND. TEMPERATURES ARE EXPECTED TO BE SLIGHTLY
ABOVE NORMAL THROUGH THE WEEKEND. UNDER HIGH PRESSURE...DRY
WEATHER CONTINUES ON MONDAY WITH TEMPERATURES MODERATING SLIGHTLY
ABOVE NORMAL. MOISTURE INCREASES MONDAY NIGHT ASSOCIATED WITH A
SOUTHERN STREAM SYSTEM. THE NEXT CHANCE FOR ANY DECENT
PRECIPITATION WILL BE TUESDAY WHEN A SYSTEM WILL MOVE UP THE COAST
FROM THE GULF. HIGH UNCERTAINTY AS THIS IS OVER A WEEK AWAY. THE
GFS IS WETTER THAN THE ECMWF. WITH TEMPERATURES BEING ABOVE NORMAL
EARLY NEXT...MOST IF NOT ALL OF THE PRECIPITATION WOULD BE RAIN.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 550 AM EST WEDNESDAY...
MAINLY IFR OR WORSE EXPECTED TO PREVAIL THIS MORNING...THOUGH
SOME POCKETS OF VFR/MVFR WILL OCCUR ESPCLY AROUND KBLF/KLWB WHERE
MORE IN THE WAY OF LIGHT RAIN OUT OF MID DECK OR HIGH BASED
STRATO-CU WILL OCCUR. SW WINDS WILL ALSO BE STRONG AROUND KBLF
THIS MORNING WITH GUSTS TO 30 KTS POSSIBLE.
THERE WILL BE VARIABILITY IN VSBYS BASED ON INTENSITY OF RAINFALL.
TYPICAL FLUCTUATIONS WILL RUN FROM 1/4 TO 3SM IN MODERATE RAIN OR
WHEN RAIN TAPERS OFF...WHILE CIGS MAY LIFT TOWARD MVFR AROUND
1-2KFT IF RAIN COMES DOWN HARD ENOUGH TO MIX OUT THE LOW CIGS
SOME. ALSO IFR TO LIFR WILL OCCUR WHERE RAIN TAPERS AND FOG
REDEVELOPS THROUGH MIDDAY. OTRW LOOKING AT POOR FLYING CONDITIONS
IN WIDESPREAD RAIN/FOG AND LOWER CIGS THIS MORNING.
AS THE FRONT APPROACHES WINDS START TO SHIFT AROUND TO THE
SOUTHWEST ALLOWING THE WEDGE ALONG THE BLUE RIDGE TO SLOWLY MIX
OUT. THE WEDGE SHOULD ERODE BY AFTERNOON...SUCH THAT MOST PLACES
WILL SEE CIGS IN MVFR WITH MVFR/IFR VSBYS WITH RAIN SHOWERS.
MODELS HAVE SPED UP THE TIMING OF DRYING IN THE WEST. THE SHOWERS
SHOULD BE EAST OF KBLF/KLWB/KBCB...17-19Z...AND KROA BY
20Z...LINGERING AT LYH/DAN TIL 22Z. WINDS WILL START TO SHIFT TO
THE WEST AT KBLF/KLWB LATE AND GUSTS TO 20 KTS CAN BE EXPECTED AT
LEAST AT KBLF DURING THIS TIME.
BEHIND THE FRONT EXPECTING UPSLOPE MVFR CIGS TO REDEVELOP AFTER
PERHAPS A PERIOD OF BRIEF VFR BEHIND THE FRONT THIS EVENING. ALSO
A FEW RAIN OR SNOW SHOWERS MAY OCCUR FROM KBLF TO KLWB BUT GIVEN
ISOLATED NATURE WONT INCLUDE ANY VSBYS REDUCTIONS OVERNIGHT. OTRW
APPEARS MVFR TO LOW END VFR CIGS WILL SNEAK BACK INTO KBCB/KROA
AFTER MIDNIGHT WHEN NW WINDS MAY GUST TO 25 OR 30 KTS ALONG THE
RIDGES. DOWNSLOPING SHOULD KEEP EASTERN SITES VFR OVERNIGHT WITH
WINDS GENERALLY BELOW 10 KTS BEHIND THE FRONT.
.EXTENDED AVIATION DISCUSSION...
SOME MVFR/OCNL IFR CIGS IN THE UPSLOPE AREAS AT KBLF AND KLWB
WILL LINGER INTO EARLY THURSDAY MORNING BEHIND FRONT...ALONG WITH
SCATTERED RAIN AND SNOW SHOWERS.
HIGH PRESSURE AND VFR CONDITIONS SHOULD DOMINATE THURSDAY NIGHT THROUGH
THE WEEKEND...HOWEVER PATCHY EARLY MORNING VALLEY FOG MAY PRODUCE
SOME BRIEF IFR CONDITIONS FRI AND SAT MORNING DUE TO MOIST GROUND
CONDITIONS FROM RECENT RAINFALL.
&&
.HYDROLOGY...
AS OF 245 AM EST WEDNESDAY...
FLOOD WATCH REMAINS IN PLACE WITH FEW ADDITIONS GIVEN OVERALL SLOW
RAINFALL RATES AND LESS COVERAGE IN THE SOUTHEAST. WITH PWATS
200-300 PERCENT OF NORMAL...THE RAINFALL EFFICIENCY SHOULD BE HIGH
THROUGH THIS MORNING WEST AND EAST INTO THE AFTERNOON WITH
PERHAPS SOME SHALLOW CONVECTION MIXING IN AS THE FRONT APPROACHES
AROUND MIDDAY. THUS THE BEST POTENTIAL FOR SMALL STREAM FLOODING
WILL BE OVER THE WEST INTO EARLY THIS AFTERNOON...MAINLY ALONG THE
SOUTHERN BLUE RIDGE AND MOUNTAIN EMPIRE REGION WITH HEAVIER
RAINFALL MOVING UP THE WESTERN SLOPES BEFORE HEADING EAST LATER
THIS MORNING.
WILL HAVE TO WATCH MAIN STEM RIVERS AND THE HEADWATERS...LIKE
UPPER ROANOKE AND DAN RIVER. PRESENTLY...THE DAN RIVER FROM
DANVILLE...DOWNSTREAM TO SOUTH BOSTON IS FAVORED TO GO TO NEAR
FLOOD STAGE BY THURSDAY MORNING...IF THE RAINFALL OF ANOTHER INCH
OR SO PANS OUT THROUGH LATER TODAY. THEREFORE GIVEN LESS RAINFALL
ACROSS THAT BASIN SO FAR WILL WAIT AND SEE HOW MUCH ACTUALLY
FALLS BEFORE ANY FLOOD WARNINGS ARE ISSUED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLOOD WATCH THROUGH THIS EVENING FOR VAZ007-009-010-012>017-
022>024-032>035-045>047.
NC...FLOOD WATCH THROUGH THIS EVENING FOR NCZ001>004-018>020.
WV...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...MBS
LONG TERM...KK/MBS
AVIATION...AMS/JH/WP
HYDROLOGY...JH/KK/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
255 AM EST WED DEC 2 2015
.SYNOPSIS...
HIGH PRESSURE WEDGED DOWN THE EASTERN SLOPES OF THE APPALACHIANS
WILL GRADUALLY ERODE THIS MORNING AHEAD OF A COLD FRONT APPROACHING
FROM THE WEST. THIS FRONT WILL CROSS THE REGION LATER TODAY AND
PASS OFFSHORE TONIGHT BRINGING AN END TO THE ONGOING WIDESPREAD
RAINFALL. HIGH PRESSURE FOLLOWS THE FRONT RESULTING IN DRIER WEATHER
AND MORE IN THE WAY OF SEASONAL TEMPERATURES INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 210 AM EST WEDNESDAY...
FLOOD THREAT REMAINS THE OVERALL CONCERN AT LEAST INTO EARLY THIS
AFTERNOON AS STEADY LIGHT TO MODERATE RAINFALL CONTINUES TO LIFT NE
THROUGH THE REGION AHEAD OF LOW PRESSURE THAT WILL PASS TO THE NW THIS
MORNING. ONCE THIS FEATURE WORKS TO THE NORTH...SHOULD SEE THE TRAILING
SURFACE COLD FRONT FINALLY SURGE EAST...AIDED BY THE PIVOTING 5H UPPER
SYSTEM CROSSING THE SOUTHERN GREAT LAKES. SOME SOLUTIONS HAVE SPED UP
THE TIMING OF EXITING THE HEAVIER RAINFALL OVER THE WEST BY MIDDAY AND
OUT EAST A FEW HOURS EARLIER THIS AFTERNOON WHICH MAY BE A BIT QUICK.
QUESTION IS WHETHER OR NOT WILL GET MUCH IN THE WAY OF SHALLOW CONVECTION
WITHIN THE AXIS OF STEADY RAIN AS SO FAR THE WEDGE HAS PRECLUDED
THIS WITH RAINFALL RATES ON THE LOW SIDE. THIS HAS RESULTED IN
ONLY SLOW RISES ON AREA STREAMS EARLY THIS MORNING.
THE LATEST HRRR CONTINUES TO HINT AT PERIODIC CLUSTERS OF HEAVIER
SHOWERS BUT MAINLY ON THE WESTERN SLOPES CLOSER TO THE SURFACE LOW AND
OUT OVER THE SOUTHEAST WHERE GUIDANCE SHOWS SOME INSTABILITY TRYING TO
MAKE A RUN BY MID AFTERNOON. MODELS HAVE ALSO CUT BACK ON THE ADDED QPF
OUTSIDE OF THE SOUTHERN BLUE RIDGE INTO THIS AFTERNOON BUT FOR NOW WILL
KEEP THE WATCH IN PLACE WITH HEAVIEST QPF STILL OVER THE FAR WEST/SW
WHERE ANOTHER 1-2 INCHES REMAINS POSSIBLE THROUGH MIDDAY...WITH
AN INCH OR LESS ELSEWHERE PER THE LATEST ECMWF. GIVEN FASTER
TRENDS ALSO PLAN TO CUT BACK POPS A BIT FASTER AFTER THIS MORNING
OVER THE WEST AND PIEDMONT BEFORE SUNSET. HIGH TEMPS TRICKY WITH
THE WEDGE LINGERING ALONG THE BLUE RIDGE AND TIMING OF PRECIP
EXODUS WHICH COULD ALLOW A QUICK SPIKE IN VALUES BEFORE THE ACTUAL
FRONT CROSSES FROM THE WEST LATER. MOST MOS NEAR OR ABOVE 60 FROM
THE BLUE RIDGE EAST SO BUMPED UP VALUES MOST LOCATIONS INCLUDING
THE FAR WEST WHERE ALREADY IN THE 50S IN SPOTS.
DECENT 85H FRONT WILL CROSS THE FAR WEST BY EARLY THIS EVENING AND THE
REST OF THE REGION OVERNIGHT. THIS SHOULD RESULT IN A QUICK UPTICK IN
COLD ADVECTION INCLUDING GUSTY NW WINDS...AND UPSLOPE DRIVEN RAIN/SNOW
SHOWERS WESTERN SLOPES WHILE AIDING DOWNSLOPE CLEARING OUT EAST. COULD
BE CLOSE TO ADVISORY LEVEL GUSTS NC MOUNTAINS PER STRONG SUBSIDENCE AND
QUICK DROP IN 85H TEMPS BUT GIVEN ONLY 40 KTS AT 85H WILL HOLD JUST
BELOW WITH THE STRONGEST SPEEDS RIGHT NEAR DAYBREAK THU. APPEARS THE
BOUNDARY LAYER WILL COOL ENOUGH TO SUPPORT SNOW SHOWERS/FLURRIES OUT
WEST MAINLY AFTER MIDNIGHT WITH PERHAPS A LIGHT COATING AT ELEVATION
FAR NW DESPITE A WET/WARM GROUND AND GUSTY WINDS. OTRW WILL HAVE
THE TYPICAL SPLIT IN SPILLOVER LOW CLOUDS WEST OF THE BLUE RIDGE
AND CLEAR OUT EAST AFTER MIDNIGHT WITH LOWS MOSTLY 30S EXCEPT ONLY
AROUND 40 PIEDMONT PENDING THE DEGREE OF MIXING.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT/...
AS OF 230 AM EST WEDNESDAY...
THE UPPER LEVEL PATTERN WILL REMAIN PROGRESSIVE WITH TRANSIENT SPLIT
FLOW CHARACTERISTICS THROUGH THE SHORT TERM...AS THE CLOSED LOW OVER
NEW ENGLAND GIVES WAY TO RIDGING OVER THE MID ATLANTIC REGION INTO THE
WEEKEND. THIS WILL ALLOW SURFACE HIGH PRESSURE TO BUILD IN FROM THE
MISSISSIPPI VALLEY AND BRING A FEW DAYS OF FAIR WEATHER TO THE
REGION...SAVE FOR BLUSTERY CONDITIONS ON THURSDAY AND SOME LINGERING
SNOW SHOWERS ALONG THE FAR WESTERN SLOPES OF THE APPALACHIANS THAT WILL
BE DISSIPATING THURSDAY MORNING.
THERE WILL BE A MODERATING TREND IN TEMPERATURES WITH HIGHS STARTING
OUT 5 TO 10 DEGREES BELOW NORMAL ON THURSDAY...THEN RISING TO SEASONAL
LEVELS OF MIDDLE 50S EAST OF THE BLUE RIDGE/UPPER 40S AND LOWER 50S
WEST BY SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 200 PM EST TUESDAY...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE
WEEKEND. A 500MB SHORTWAVE MOVES ACROSS THE SOUTHEAST UNITED STATES
DURING THE PERIOD. HOWEVER...OPERATIONAL AND ENSEMBLE MODELS DIFFER
IN THE INTENSITY AND LOCATION OF THIS FEATURE. THE GFS CUTS OFF THE
LOW OVER THE CENTRAL APPALACHIANS...WHILE THE ECMWF REMAINS AN OPEN
WAVE AND PUSHES IT OUT TO SEA. IN ANY CASE ...THE MOISTURE WITH
THIS FEATURE REMAINS LIMITED...WITH 500MB HEIGHTS RISING IN THE
EAST INTO THE WEEKEND. TEMPERATURES ARE EXPECTED TO BE SLIGHTLY
ABOVE NORMAL THROUGH THE WEEKEND. UNDER HIGH PRESSURE...DRY
WEATHER CONTINUES ON MONDAY WITH TEMPERATURES MODERATING SLIGHTLY
ABOVE NORMAL. MOISTURE INCREASES MONDAY NIGHT ASSOCIATED WITH A
SOUTHERN STREAM SYSTEM. THE NEXT CHANCE FOR ANY DECENT
PRECIPITATION WILL BE TUESDAY WHEN A SYSTEM WILL MOVE UP THE COAST
FROM THE GULF. HIGH UNCERTAINTY AS THIS IS OVER A WEEK AWAY. THE
GFS IS WETTER THAN THE ECMWF. WITH TEMPERATURES BEING ABOVE NORMAL
EARLY NEXT...MOST IF NOT ALL OF THE PRECIPITATION WOULD BE RAIN.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
AS OF 1145 PM EST TUESDAY...
MAINLY IFR OR WORSE EXPECTED THROUGH WEDNESDAY MORNING...THOUGH
SOME POCKETS OF VFR WITH MIXING WITH MODERATE TO HEAVY RAIN.
THERE WILL BE VARIABILITY IN VSBYS BASED ON INTENSITY OF RAINFALL.
TYPICAL FLUCTUATIONS WILL RUN FROM 1/4 TO 1SM IN MODERATE RAIN OR
WHEN RAIN TAPERS OFF...WHILE CIGS MAY LIFT TOWARD MVFR AROUND
1-2KFT IF RAIN COMES DOWN HARD ENOUGH TO MIX OUT THE LOW CIGS
SOME.
CONFIDENCE REMAINS HIGH THAT 00Z-15Z WILL SEE SUB MVFR CONDITIONS
AT ALL SITES.
AS THE FRONT APPROACHES WED WINDS START TO SHIFT AROUND TO THE
SOUTHWEST WITH A BKN AREA OF SHOWERS MOVING IN. THE WEDGE ERODES
BY AFTERNOON...SUCH THAT MOST PLACES WILL SEE CIGS IN MVFR WITH
MVFR/IFR VSBYS WITH RAIN SHOWERS. MODELS HAVE SPED UP THE TIMING
OF DRYING IN THE WEST. THE SHOWERS SHOULD BE EAST OF
BLF/LWB/BCB...17-19Z...AND ROA BY 19Z...LINGERING AT LYH/DAN TIL
22Z. WINDS WILL START TO SHIFT TO THE WEST AT BLF/LWB LATE AND
GUSTS TO 20 KTS CAN BE EXPECTED AT LEAST AT BLF DURING THIS TIME.
SHOULD SEE WEST WINDS AT ALL SITES AFTER 00Z THU.
.EXTENDED AVIATION DISCUSSION...
SOME IFR IN UPSLOPE AREAS AT KBLF AND KLWB WILL LINGER INTO EARLY
THURSDAY MORNING BEHIND FRONT...ALONG WITH SCATTERED RAIN AND SNOW
SHOWERS. ALSO BEHIND THE FRONT WEDNESDAY NIGHT INTO THURSDAY...
GUSTY NORTHWEST WINDS CAN BE EXPECTED.
HIGH PRESSURE AND VFR CONDITIONS SHOULD DOMINATE THURSDAY NIGHT THROUGH
THE WEEKEND...HOWEVER PATCHY EARLY MORNING VALLEY FOG MAY PRODUCE
SOME BRIEF IFR CONDITIONS FRI AND SAT MORNING DUE TO MOIST GROUND
CONDITIONS FROM RECENT RAINFALL.
&&
.HYDROLOGY...
AS OF 245 AM EST WEDNESDAY...
FLOOD WATCH REMAINS IN PLACE WITH FEW ADDITIONS GIVEN OVERALL SLOW
RAINFALL RATES AND LESS COVERAGE IN THE SOUTHEAST. WITH PWATS
200-300 PERCENT OF NORMAL...THE RAINFALL EFFICIENCY SHOULD BE HIGH
THROUGH THIS MORNING WEST AND EAST INTO THE AFTERNOON WITH
PERHAPS SOME SHALLOW CONVECTION MIXING IN AS THE FRONT APPROACHES
AROUND MIDDAY. THUS THE BEST POTENTIAL FOR SMALL STREAM FLOODING
WILL BE OVER THE WEST INTO EARLY THIS AFTERNOON...MAINLY ALONG THE
SOUTHERN BLUE RIDGE AND MOUNTAIN EMPIRE REGION WITH HEAVIER
RAINFALL MOVING UP THE WESTERN SLOPES BEFORE HEADING EAST LATER
THIS MORNING.
WILL HAVE TO WATCH MAIN STEM RIVERS AND THE HEADWATERS...LIKE
UPPER ROANOKE AND DAN RIVER. PRESENTLY...THE DAN RIVER FROM
DANVILLE...DOWNSTREAM TO SOUTH BOSTON IS FAVORED TO GO TO NEAR
FLOOD STAGE BY THURSDAY MORNING...IF THE RAINFALL OF ANOTHER INCH
OR SO PANS OUT THROUGH LATER TODAY. THEREFORE GIVEN LESS RAINFALL
ACROSS THAT BASIN SO FAR WILL WAIT AND SEE HOW MUCH ACTUALLY
FALLS BEFORE ANY FLOOD WARNINGS ARE ISSUED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLOOD WATCH THROUGH THIS EVENING FOR VAZ007-009-010-012>017-
022>024-032>035-045>047.
NC...FLOOD WATCH THROUGH THIS EVENING FOR NCZ001>004-018>020.
WV...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...MBS
LONG TERM...KK/MBS
AVIATION...AMS/SK/WP
HYDROLOGY...JH/KK/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1157 PM EST TUE DEC 1 2015
.SYNOPSIS...
HIGH PRESSURE WEDGED DOWN THE APPALACHIANS WILL GRADUALLY ERODE
TONIGHT AND WEDNESDAY. A COLD FRONT WILL CROSS THROUGH THE AREA
LATE ON WEDNESDAY...FOLLOWED BY HIGH PRESSURE FOR THURSDAY THROUGH
SATURDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 935 PM EST TUESDAY...
KEEPING WITH THE HIGH-RES MODELS SHOWING WIDESPREAD RAINFALL
MOVING ACROSS THROUGH EARLY MORNING. RAINFALL AMOUNTS IN THE PAST
6 HOURS HAS NOT BEEN TOO BAD...MAINLY STAYING UNDER ONE HALF INCH.
HIGHER AMOUNTS PER RADAR HAS BEEN ONE HALF TO JUST OVER THREE
QUARTERS OF AN INCH IN SOUTHERN WILKES AND YADKIN COUNTIES.
00Z PWAT FROM RNK WAS 1.06" AND MESOANALYSIS DEPICTS PWATS OF 1 TO
1.2 INCHES IN THE REGION...WHICH IS RUNNING ALMOST 3 SD ABOVE
NORMAL. HENCE THE FLOOD WATCH STILL LOOKS GOOD THROUGH WEDNESDAY.
NO MAJOR CHANGES NEED TO THE CURRENT FORECAST.
PREVIOUS EARLY EVENING DISCUSSION...
MODIFIED FORECAST THIS EVENING TO ACCOUNT FOR RADAR TRENDS...WHICH
MATCHED WELL WITH THE 22Z HRRR AND TO SOME EXTENT THE 18Z NAM.
MODERATE RAIN WILL SPREAD ACROSS THE SW CWA AFTER 8 PM...WITH
LIGHT TO MODERATE RAIN ACROSS THE REST OF THE CWA...ESPECIALLY
ALONG AND SOUTH OF THE NC/VA BORDER TIL 8 PM.
MOST LOCATIONS WILL SEE INCREASE IN RAINFALL BY MIDNIGHT...WHERE
IT WILL BECOME HEAVY AT TIMES OVER THE NC
MOUNTAINS/FOOTHILLS...NWD INTO THE MOUNTAIN EMPIRE INTO THE NEW
RIVER VALLEY. UPPER RAINFALL AMOUNTS ABOUT 1/4 INCH IN A FEW
LOCATIONS IN THE SW...THOUGH 24 TOTALS WILL RANGE FROM 1-2"
BETWEEN 7 PM THIS EVENING AND 7 PM WEDNESDAY.
PREVIOUS AFTERNOON DISCUSSION...
SHALLOW WEDGE WAS STILL IN PLACE THIS AFTERNOON. WINDS WERE FROM
THE SOUTHWEST BUT WIND SPEEDS WERE LIGHT. MSAS LIFTED INDEX
ANALYSIS SHOWED THE WEDGE EXTENDED WELL INTO NORTH CAROLINA.
BUFKIT FORECAST HAD THE DEPTH OF THE WEDGE LESS THAN 1500 FEET.
TEMPERATURES HAVE SHOWN A VERY SLOW RISE TODAY. THE HIGHEST
ELEVATIONS...LIKE HOT SPRINGS...THAT WERE ABOVE THE INVERSION
HAD WARMED INTO THE 50S.
WATER VAPOR LOOP CONTINUED TO SHOW A LONG PLUME OF MOISTURE FROM
THE PACIFIC INTO THE SOUTHEAST UNITED STATES AND MID ATLANTIC
REGION. CHALLENGING TO DISCERN ANY OF THE SHORT WAVES IN THIS FLOW
BUT A SURFACE LOW WILL DEVELOP IN THE TENNESSEE VALLEY ALONG THE
COLD FRONT TONIGHT. EXPECT THIS TO BACK THE WINDS AND HELP
INCREASE ISENTROPIC LIFT OVER THE REGION. SYNOPTIC SCALE FORCING
REMAINS STRONG THROUGH WEDNESDAY MORNING.
STAYED WITH A NON DIURNAL TEMPERATURE TREND OVERNIGHT AND FOR
WEDNESDAY. HAVE INCREASED THE PROBABILITY OF PRECIPITATION IN MOST
LOCATIONS BEFORE WEDNESDAY AFTERNOON. MODELS IN DECENT AGREEMENT
THAT WINDS WILL TURN TO THE WEST IN THE AFTERNOON WITH THE BACK
EDGE OF THE PRECIPITATION ADVANCING ACROSS THE FORECAST AREA FROM
WEST TO EAST.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 230 PM EST TUESDAY...
UPPER LEVEL CLOSED LOW OVER THE GREAT LAKES WILL MOVE NORTHEAST TO
OFF THE NEW ENGLAND COAST BY THURSDAY AFTERNOON. THIS LOW WILL
CONTINUE TO PUSH NORTHEAST INTO THE ATLANTIC OCEAN THURSDAY NIGHT
INTO FRIDAY NIGHT.
A SURFACE WAVE OF LOW PRESSURE ALONG THE COLD FRONT WILL LIFT
NORTHEAST AS IT PASSES THROUGH OUR AREA. BY WEDNESDAY
AFTERNOON...THE LOW CENTER WILL BE LOCATED ACROSS NORTHERN VIRGINIA
ON ITS WAY TO SOUTHERN NEW ENGLAND BY WEDNESDAY NIGHT.
BEHIND THE COLD FRONT LATE WEDNESDAY AND WEDNESDAY NIGHT...BLUSTERY
NORTHWEST WINDS WILL USHER IN COLDER AIR AND GENERATE SOME UPSLOPE
RAIN/TO/SNOW SHOWERS ALONG THE FAR WESTERN SLOPES. NO SIGNIFICANT
SNOW ACCUMULATIONS ARE EXPECTED THROUGH SOME LOCATIONS MAY SEE A
LIGHT COATING IN THE FAVORED UPSLOPE AREA. WIND SPEEDS SHOULD REMAIN
BELOW WIND ADVISORY LEVELS IN THE MOUNTAINS WEDNESDAY NIGHT.
HOWEVER...NORTHWEST WINDS WILL BE GUSTY WITH A 40 KNOT 850 MB JET
AND 4 TO 5MB 6 HOUR PRESSURE RISES ON THE GFS. HIGH PRESSURE OVER
THE OHIO VALLEY WILL BUILD EAST OVER THE MID ATLANTIC REGION
THURSDAY AND CONTINUE THROUGH THE END OF THE WORKWEEK.
LOW TEMPERATURES WEDNESDAY NIGHT WILL VARY FROM THE MID 20S IN THE
NORTHWEST MOUNTAINS TO AROUND 40 DEGREES IN THE PIEDMONT. COOLER
HIGH TEMPERATURES ANTICIPATED THURSDAY WITH READINGS FROM THE LOWER
30S IN THE MOUNTAINS TO THE LOWER 50S IN THE PIEDMONT. UNDER MOSTLY
CLEAR SKIES...LOW TEMPERATURES THURSDAY NIGHT WILL DROP INTO THE MID
20S IN THE WEST TO AROUND 30 DEGREES IN THE EAST. HIGH TEMPERATURES
MODERATE ON FRIDAY INTO THE LOWER 40S IN THE WEST TO THE LOW 50S IN
THE EAST. IT WILL BE COLD FRIDAY NIGHT WITH VALUES DROPPING TO THE
MID 20S IN THE NORTHWEST TO THE LOWER 30S IN THE SOUTHEAST.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 200 PM EST TUESDAY...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE
WEEKEND. A 500MB SHORTWAVE MOVES ACROSS THE SOUTHEAST UNITED STATES
DURING THE PERIOD. HOWEVER...OPERATIONAL AND ENSEMBLE MODELS DIFFER
IN THE INTENSITY AND LOCATION OF THIS FEATURE. THE GFS CUTS OFF THE
LOW OVER THE CENTRAL APPALACHIANS...WHILE THE ECMWF REMAINS AN OPEN
WAVE AND PUSHES IT OUT TO SEA. IN ANY CASE ...THE MOISTURE WITH
THIS FEATURE REMAINS LIMITED...WITH 500MB HEIGHTS RISING IN THE
EAST INTO THE WEEKEND. TEMPERATURES ARE EXPECTED TO BE SLIGHTLY
ABOVE NORMAL THROUGH THE WEEKEND. UNDER HIGH PRESSURE...DRY
WEATHER CONTINUES ON MONDAY WITH TEMPERATURES MODERATING SLIGHTLY
ABOVE NORMAL. MOISTURE INCREASES MONDAY NIGHT ASSOCIATED WITH A
SOUTHERN STREAM SYSTEM. THE NEXT CHANCE FOR ANY DECENT
PRECIPITATION WILL BE TUESDAY WHEN A SYSTEM WILL MOVE UP THE COAST
FROM THE GULF. HIGH UNCERTAINTY AS THIS IS OVER A WEEK AWAY. THE
GFS IS WETTER THAN THE ECMWF. WITH TEMPERATURES BEING ABOVE NORMAL
EARLY NEXT...MOST IF NOT ALL OF THE PRECIPITATION WOULD BE RAIN.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 1145 PM EST TUESDAY...
MAINLY IFR OR WORSE EXPECTED THROUGH WEDNESDAY MORNING...THOUGH
SOME POCKETS OF VFR WITH MIXING WITH MODERATE TO HEAVY RAIN.
THERE WILL BE VARIABILITY IN VSBYS BASED ON INTENSITY OF RAINFALL.
TYPICAL FLUCTUATIONS WILL RUN FROM 1/4 TO 1SM IN MODERATE RAIN OR
WHEN RAIN TAPERS OFF...WHILE CIGS MAY LIFT TOWARD MVFR AROUND
1-2KFT IF RAIN COMES DOWN HARD ENOUGH TO MIX OUT THE LOW CIGS
SOME.
CONFIDENCE REMAINS HIGH THAT 00Z-15Z WILL SEE SUB MVFR CONDITIONS
AT ALL SITES.
AS THE FRONT APPROACHES WED WINDS START TO SHIFT AROUND TO THE
SOUTHWEST WITH A BKN AREA OF SHOWERS MOVING IN. THE WEDGE ERODES
BY AFTERNOON...SUCH THAT MOST PLACES WILL SEE CIGS IN MVFR WITH
MVFR/IFR VSBYS WITH RAIN SHOWERS. MODELS HAVE SPED UP THE TIMING
OF DRYING IN THE WEST. THE SHOWERS SHOULD BE EAST OF
BLF/LWB/BCB...17-19Z...AND ROA BY 19Z...LINGERING AT LYH/DAN TIL
22Z. WINDS WILL START TO SHIFT TO THE WEST AT BLF/LWB LATE AND
GUSTS TO 20 KTS CAN BE EXPECTED AT LEAST AT BLF DURING THIS TIME.
SHOULD SEE WEST WINDS AT ALL SITES AFTER 00Z THU.
.EXTENDED AVIATION DISCUSSION...
SOME IFR IN UPSLOPE AREAS AT KBLF AND KLWB WILL LINGER INTO EARLY
THURSDAY MORNING BEHIND FRONT...ALONG WITH SCATTERED RAIN AND SNOW
SHOWERS. ALSO BEHIND THE FRONT WEDNESDAY NIGHT INTO THURSDAY...
GUSTY NORTHWEST WINDS CAN BE EXPECTED.
HIGH PRESSURE AND VFR CONDITIONS SHOULD DOMINATE THURSDAY NIGHT THROUGH
THE WEEKEND...HOWEVER PATCHY EARLY MORNING VALLEY FOG MAY PRODUCE
SOME BRIEF IFR CONDITIONS FRI AND SAT MORNING DUE TO MOIST GROUND
CONDITIONS FROM RECENT RAINFALL.
&&
.HYDROLOGY...
AS OF 950 PM AM EST TUESDAY...
FLOOD WATCH STILL LOOKS REASONABLE FOR THE LOCATIONS IT
COVERS. WITH PWATS 200-300 PERCENT OF NORMAL...THE RAINFALL
EFFICIENCY SHOULD BE HIGH THROUGH WEDNESDAY. CURRENTLY...THE
THREAT FOR SMALL STREAM FLOODING WILL BE OVERNIGHT...MAINLY AFTER
1AM...IN THE NC MTNS/FOOTHILLS WHERE THE HEAVIER RAIN MOVES UP
FROM THE SMOKYS.
WILL HAVE TO WATCH MAIN STEM RIVERS AND THE HEADWATERS...LIKE
UPPER ROANOKE AND DAN RIVER. PRESENTLY...THE DAN RIVER FROM
DANVILLE...DOWNSTREAM TO SOUTH BOSTON IS FAVORED TO GO TO NEAR
FLOOD STAGE BY THURSDAY MORNING...IF THE RAINFALL OF 1-2 INCHES
PANS OUT THROUGH TOMORROW. WILL WAIT AND SEE HOW MUCH ACTUALLY
FALLS BEFORE ANY FLOOD WARNINGS ARE ISSUED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR VAZ007-009-010-
012>017-022>024-032>035-045>047.
NC...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR NCZ001>004-018>020.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/WP
SHORT TERM...KK
LONG TERM...KK
AVIATION...AMS/SK/WP
HYDROLOGY...KK/SK/WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
130 PM CST WED DEC 2 2015
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 130 PM CST WED DEC 2 2015
CLOUD TRENDS THROUGH TONIGHT AND FOG POTENTIAL THURSDAY NIGHT ARE
THE MAIN CONCERNS IN THE SHORT TERM.
LOOP OF WATER VAPOR SATELLITE IMAGERY AND RAP ANALYSIS SHOW CENTER
OF CLOSED LOW ALONG THE WI/IL BORDER THIS AFTERNOON. LIGHT SNOW
ACTIVITY ASSOCIATED WITH THE LOW HAS SHIFTED EAST OF THE AREA.
MEANWHILE...LINGERING DEFORMATION CLOUD COVER HANGING ACROSS THE
REGION WITH TEMPERATURES IN THE LOWER 30S.
FOR TONIGHT...MODELS AND SYNTHETIC LOW CLOUD/FOG IMAGERY SHOW A SLOW
WEST TO EAST CLEARING OF THE CLOUD COVER //BASICALLY UP TO THE
MISSISSIPPI RIVER BY SUNRISE// AS THE LOW PULLS EAST INTO THE GREAT
LAKES REGION. THIS CLEARING WILL PROVIDE FOR SEASONALLY CHILLY
OVERNIGHT LOWS WEST OF THE MISSISSIPPI IN THE TEENS...WHILE ALONG
AND EAST OF THE RIVER UNDER MORE CLOUD COVER TEMPERATURES
ARE EXPECTED SETTLE INTO THE MIDDLE 20S.
HIGH PRESSURE BUILDING INTO THE AREA THURSDAY WILL PRODUCE INCREASED
SUNSHINE WITH HIGHS TOPPING OFF IN THE MIDDLE 30S TO A FEW LOWER
40S. THIS WILL MELT MOST OF THE SNOW THAT FELL THE LAST COUPLE DAY.
THERE IS SOME CONCERN WHAT IMPACT ALL THAT MELTED SNOW WILL HAVE ON
FOG/STRATUS POTENTIAL LATE THURSDAY NIGHT. WHILE NAM/GFS SOUNDINGS
ARE DRY...SREF SHOWS HIGH PROBABILITY OF LOW CLOUD/FOG GIVEN THE
DAMP LOWER BOUNDARY LAYER AND RIDGE OF HIGH PRESSURE OVERHEAD. FOR
NOW...HAVE ADDED PATCHY FOG MENTION AND WILL HAVE TO WAIT TO SEE
WHAT TOMORROW BRINGS AS FAR AS DEW POINT RESPONSE TO THE SNOW MELT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 130 PM CST WED DEC 2 2015
FOG POTENTIAL FRIDAY MORNING AND PRECIPITATION CHANCE SATURDAY NIGHT
ARE THE MAIN LONG TERM CONCERNS.
WILL HAVE TO WATCH FRIDAY MORNING AS THERE COULD BE SOME LINGERING
FOG POTENTIAL...BUT AS THE RIDGE AXIS SHIFTS EAST AND SOUTHWEST
WINDS KICK IN FOR MIXING...SUNSHINE SHOULD BE AMPLE THROUGH THE REST
OF THE DAY. GFS/NAM SHOWING 925MB TEMPERATURES INCREASING TO 6-8C BY
AFTERNOON...WHICH SHOULD PRODUCE HIGHS AT THE SURFACE IN THE 40S.
SATURDAY WILL LIKELY SEE AN INCREASE IN CLOUD COVER...ESPECIALLY BY
LATER IN THE AFTERNOON. THIS WILL BE AHEAD OF AN APPROACHING MID-
LEVEL TROUGH/SURFACE COLD FRONT MAKING ITS WAY EAST ACROSS THE
PLANS. OTHERWISE...PLAN ON HIGHS WELL ABOVE NORMAL IN THE
MIDDLE/UPPER 40S.
FOR SATURDAY NIGHT...THE NAM/GFS/ECMWF ALL SHOW A GOOD AMOUNT OF LOW-
LEVEL/0.5KM MOISTURE ADVECTING NORTHEASTWARD INTO THE AREA FOR AN
INCREASE IN STRATUS CLOUD COVER. THE GFS ALSO SHOWING DECENT/DEEP850-
500MB FRONTOGENESIS ALONG/BEHIND THE FRONTAL BOUNDARY FOR ENOUGH
FORCING FOR SOME LIGHT RAIN OR SNOW. ADDED A LIGHT CHANCE MENTION
FOR NOW.
LOOKS QUIET/MILD THROUGH THE REST OF THE PERIOD AS STORM TRACK
REMAINS WELL NORTH INTO CANADA. PLAN ON HIGHS REMAINING NEARLY 10
DEGREES ABOVE NORMAL IN THE UPPER 30S TO THE MIDDLE 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1115 AM CST WED DEC 2 2015
A WEDGE OF DRIER LOW LEVEL AIR HAS WRAPPED INTO THE TAF SITES AROUND
LOW PRESSURE NEAR LAKE MICHIGAN...CAUSING BOTH TAF SITES TO BECOME
VFR ON SKY CONDITION. MEANWHILE...LURKING TO THE WEST NEAR I-35
AND INTO WESTERN MN IS A LOW CLOUD DECK WITH IFR/MVFR CEILINGS.
TOUGH TO SAY EXACTLY WHEN THESE WILL MOVE INTO THE TAF SITES GIVEN
SOME POOR MODEL FORECASTS OF THIS CURRENT WEDGE OF DRY AIR.
HOWEVER...WITH A NORTHWEST LOW LEVEL WIND DEVELOPING...THE CLOUDS
ARE GOING TO GET THERE. CURRENTLY HAVE 22Z FOR RST AND 02Z AT
LSE BUT THIS TIMING MAY NEED ADJUSTMENT. ALSO HAVE MAINTAINED THE
CLOUD DECK AS A LOW MVFR FOR NOW. WITH A NORTHWEST TO WEST FLOW
PERSISTING THROUGH THE NIGHT...THE BACK EDGE OF THE CLOUDS SHOULD
MOVE THROUGH RST AROUND 10Z AND LSE AROUND 14Z...WITH VFR
CONDITIONS THEREAFTER. NO VISIBILITY RESTRICTIONS ARE EXPECTED
OVER THE NEXT 24 HOURS WHILE WINDS REMAIN UNDER 10 KT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
118 AM CST WED DEC 2 2015
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 117 AM CST WED DEC 2 2015
WILL UP SNOW AMOUNTS OVER PARTS OF CENTRAL WISCONSIN
OVERNIGHT AS THE COLD UPPER LOW WITH A MODEST 900-800 MB SNOW
GROWTH REGION WAS COMBINING WITH A SURFACE CONVERGENT REGION IN
THE SURFACE LOW. ALREADY 2 INCH AMOUNTS REPORTED...AND LOOKS VERY
STATIONARY. WILL CERTAINLY UPDATE THE SPS BUT A SHORT FUSE
ADVISORY MAY BE NEEDED.
&&
.SYNOPSIS...
ISSUED AT 217 PM CST TUE DEC 1 2015
ONCE THE SCATTERED LIGHT PRECIPITATION ENDS TOMORROW...QUIET AND
MILD EARLY-WINTER WEATHER IS EXPECTED THROUGH THE UPCOMING
WEEKEND AND INTO NEXT WEEK.
THE UPR FLOW ACRS NOAM WL REMAIN SPLIT THROUGHOUT THE PERIOD AND
BEYOND...WITH A DOMINANT NRN STREAM ACRS CANADA...AND A WEAKER SRN
STREAM ACROS THE SRN CONUS. ONCE THE GRADUALLY WEAKENING REMNANTS
OF SRN STREAM UPR TROF SHIFT OFF TO THE E LATE TOMORROW...THE
FCST AREA WL PRETTY MUCH REMAIN BETWEEN THE MAIN BRANCHES OF THE
FLOW. THAT FAVORS ABOVE NORMAL TEMPERATURES AND LITTLE IF ANY
PRECIPITATION THROUGH AT LEAST THE END OF THE FORECAST PERIOD.
&&
.SHORT TERM...TONIGHT AND WEDNESDAY
ISSUED AT 217 PM CST TUE DEC 1 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A BROAD
UPPER LEVEL LOW PRESSURE SYSTEM SPINNING OVER THE NORTHERN
MISSISSIPPI VALLEY EARLY THIS AFTERNOON. ITS ASSOCIATED OCCLUDED
FRONT AND BAND OF PRECIPITATION HAVE SHIFTED NORTH INTO THE UPPER
PENINSULA. MORE WIDELY SCATTERED RAIN AND SNOW SHOWER ACTIVITY ARE
MOVING NORTHEAST BEHIND THE FRONT AND ACROSS THE REGION. SOME
DRIZZLE ALSO MIXED IN AS WELL...MAINLY OVER NORTH-CENTRAL WI.
LOOKING UPSTREAM...ANOTHER AREA OF LIGHT SNOW IS MOVING NORTHEAST
AROUND THE UPPER LOW OVER IOWA. SOME FREEZING DRIZZLE COULD BE
MIXED IN WITH THE SNOW. AS THE UPPER LOW SHIFTS MOVES ACROSS THE
REGION...PRECIP TRENDS ARE THE MAIN FORECAST CONCERN.
TONIGHT...THE UPPER LEVEL LOW WILL MOVE NORTHEAST INTO CENTRAL
WISCONSIN BY 09Z. WRAP AROUND DEEPER MOISTURE WILL ACCOMPANY THE
UPPER LOW AND MOVE FROM SOUTHWEST TO NORTHEAST DURING THE EVENING.
HOWEVER...PROGGED SOUNDINGS INDICATE THAT THE DEEPER MOISTURE HAS
TROUBLE REMAINING SATURATED BELOW 700MB...WHICH WOULD INDICATE MORE
OF A SPOTTY/SCATTERED SNOW SHOWER THREAT. OBS ARE ALSO SHOWING
UNKNOWN PRECIP IN SPOTS OVER IOWA...WHICH COULD BE FREEZING DRIZZLE.
SO WILL INCLUDE BOTH LIGHT SNOW AND FREEZING DRIZZLE IN THE
FORECAST...BUT WITH LITTLE TO NO ACCUMULATION OF EITHER. A FEW
SPOTS COULD SEE A HALF INCH OF SNOW. LOWS RANGING FROM THE MID 20S
WEST TO NEAR 30 BY THE LAKE.
WEDNESDAY...THE UPPER LOW WILL MOVE TO THE SOUTHEAST TO SOUTHERN
LAKE MICHIGAN BY MIDDAY AND SOUTHERN LOWER MICHIGAN BY 00Z THU. THE
CHANCE OF LIGHT SNOW SHOWERS WILL EXIT WITH THE UPPER LOW BY EARLY
AFTERNOON. THOUGH THERE WILL LIKELY BE BREAKS IN THE OVERCAST
DEVELOPING DURING THE AFTERNOON...WILL MAINTAIN BROKEN CONDITIONS IN
THE FORECAST THROUGH THE DAY. PLENTY OF CLOUDS AND COLD TEMPS UNDER
THE UPPER LOW CALLS FOR HIGHS MAINLY IN THE MID 30S.
.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY
ISSUED AT 217 PM CST TUE DEC 1 2015
ANY LINGERING FLURRIES IN THE N SHOULD END WEDNESDAY EVENING...
WITH CLDS PROBABLY LINGERING INTO EARLY THURSDAY BEFORE
DECREASING. TEMPERATURES WL REMAIN ABV NORMAL FOR THIS TIME OF
YEAR. BASED TEMPS ON A BROAD-BASED BLEND OF GUIDANCE
PRODUCTS...TWEAKED TOWARD THOSE PRODUCTS THAT HAVE PERFORMED WELL
LATELY.
NO SIG CHGS TO THE EXTENDED FCST GRIDS BASED ON A BROAD-BASED
BLEND OF GUIDANCE PRODUCTS.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1054 PM CST TUE DEC 1 2015
UPPER LEVEL LOW PRESSURE WILL CONTINUE MOVING ACROSS
THE REGION TONIGHT. CONDITIONS HAVE VARIED GREATLY BETWEEN VFR AND
IFR THROUGHOUT THE NIGHT...AND WILL CONTINUE TO DO SO THROUGH
WEDNESDAY AS THE LOW TRACKS OVER THE REGION. UPSTREAM
OBSERVATIONS AND MOS GUIDANCE ARE OF LITTLE ASSISTANCE AS THEY ARE
ALL OVER THE PLACE. FOR NOW WILL GO WITH A WORSE CASE SCENARIO
WITH THIS SET OF TAFS. SCATTERED SNOW SHOWERS WILL CONTINUE ACROSS
THE REGION THROUGH EARLY WEDNESDAY MORNING...WITH SOME LIGHT
ACCUMULATIONS POSSIBLE OVER CENTRAL AND NORTH CENTRAL WISCONSIN.
OTHERWISE...THE UPPER LOW STARTS TO MOVE OUT WED AFTERNOON...AND
SHOULD SEE IMPROVING CONDITIONS START TO PUSH INTO THE REGION BY
THE EVENING HOURS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........TDH
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......KURIMSKI
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1054 PM CST TUE DEC 1 2015
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SYNOPSIS...
ISSUED AT 217 PM CST TUE DEC 1 2015
ONCE THE SCATTERED LIGHT PRECIPITATION ENDS TOMORROW...QUIET AND
MILD EARLY-WINTER WEATHER IS EXPECTED THROUGH THE UPCOMING
WEEKEND AND INTO NEXT WEEK.
THE UPR FLOW ACRS NOAM WL REMAIN SPLIT THROUGHOUT THE PERIOD AND
BEYOND...WITH A DOMINANT NRN STREAM ACRS CANADA...AND A WEAKER SRN
STREAM ACROS THE SRN CONUS. ONCE THE GRADUALLY WEAKENING REMNANTS
OF SRN STREAM UPR TROF SHIFT OFF TO THE E LATE TOMORROW...THE
FCST AREA WL PRETTY MUCH REMAIN BETWEEN THE MAIN BRANCHES OF THE
FLOW. THAT FAVORS ABOVE NORMAL TEMPERATURES AND LITTLE IF ANY
PRECIPITATION THROUGH AT LEAST THE END OF THE FORECAST PERIOD.
&&
.SHORT TERM...TONIGHT AND WEDNESDAY
ISSUED AT 217 PM CST TUE DEC 1 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A BROAD
UPPER LEVEL LOW PRESSURE SYSTEM SPINNING OVER THE NORTHERN
MISSISSIPPI VALLEY EARLY THIS AFTERNOON. ITS ASSOCIATED OCCLUDED
FRONT AND BAND OF PRECIPITATION HAVE SHIFTED NORTH INTO THE UPPER
PENINSULA. MORE WIDELY SCATTERED RAIN AND SNOW SHOWER ACTIVITY ARE
MOVING NORTHEAST BEHIND THE FRONT AND ACROSS THE REGION. SOME
DRIZZLE ALSO MIXED IN AS WELL...MAINLY OVER NORTH-CENTRAL WI.
LOOKING UPSTREAM...ANOTHER AREA OF LIGHT SNOW IS MOVING NORTHEAST
AROUND THE UPPER LOW OVER IOWA. SOME FREEZING DRIZZLE COULD BE
MIXED IN WITH THE SNOW. AS THE UPPER LOW SHIFTS MOVES ACROSS THE
REGION...PRECIP TRENDS ARE THE MAIN FORECAST CONCERN.
TONIGHT...THE UPPER LEVEL LOW WILL MOVE NORTHEAST INTO CENTRAL
WISCONSIN BY 09Z. WRAP AROUND DEEPER MOISTURE WILL ACCOMPANY THE
UPPER LOW AND MOVE FROM SOUTHWEST TO NORTHEAST DURING THE EVENING.
HOWEVER...PROGGED SOUNDINGS INDICATE THAT THE DEEPER MOISTURE HAS
TROUBLE REMAINING SATURATED BELOW 700MB...WHICH WOULD INDICATE MORE
OF A SPOTTY/SCATTERED SNOW SHOWER THREAT. OBS ARE ALSO SHOWING
UNKNOWN PRECIP IN SPOTS OVER IOWA...WHICH COULD BE FREEZING DRIZZLE.
SO WILL INCLUDE BOTH LIGHT SNOW AND FREEZING DRIZZLE IN THE
FORECAST...BUT WITH LITTLE TO NO ACCUMULATION OF EITHER. A FEW
SPOTS COULD SEE A HALF INCH OF SNOW. LOWS RANGING FROM THE MID 20S
WEST TO NEAR 30 BY THE LAKE.
WEDNESDAY...THE UPPER LOW WILL MOVE TO THE SOUTHEAST TO SOUTHERN
LAKE MICHIGAN BY MIDDAY AND SOUTHERN LOWER MICHIGAN BY 00Z THU. THE
CHANCE OF LIGHT SNOW SHOWERS WILL EXIT WITH THE UPPER LOW BY EARLY
AFTERNOON. THOUGH THERE WILL LIKELY BE BREAKS IN THE OVERCAST
DEVELOPING DURING THE AFTERNOON...WILL MAINTAIN BROKEN CONDITIONS IN
THE FORECAST THROUGH THE DAY. PLENTY OF CLOUDS AND COLD TEMPS UNDER
THE UPPER LOW CALLS FOR HIGHS MAINLY IN THE MID 30S.
.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY
ISSUED AT 217 PM CST TUE DEC 1 2015
ANY LINGERING FLURRIES IN THE N SHOULD END WEDNESDAY EVENING...
WITH CLDS PROBABLY LINGERING INTO EARLY THURSDAY BEFORE
DECREASING. TEMPERATURES WL REMAIN ABV NORMAL FOR THIS TIME OF
YEAR. BASED TEMPS ON A BROAD-BASED BLEND OF GUIDANCE
PRODUCTS...TWEAKED TOWARD THOSE PRODUCTS THAT HAVE PERFORMED WELL
LATELY.
NO SIG CHGS TO THE EXTENDED FCST GRIDS BASED ON A BROAD-BASED
BLEND OF GUIDANCE PRODUCTS.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1054 PM CST TUE DEC 1 2015
UPPER LEVEL LOW PRESSURE WILL CONTINUE MOVING ACROSS
THE REGION TONIGHT. CONDITIONS HAVE VARIED GREATLY BETWEEN VFR AND
IFR THROUGHOUT THE NIGHT...AND WILL CONTINUE TO DO SO THROUGH
WEDNESDAY AS THE LOW TRACKS OVER THE REGION. UPSTREAM
OBSERVATIONS AND MOS GUIDANCE ARE OF LITTLE ASSISTANCE AS THEY ARE
ALL OVER THE PLACE. FOR NOW WILL GO WITH A WORSE CASE SCENARIO
WITH THIS SET OF TAFS. SCATTERED SNOW SHOWERS WILL CONTINUE ACROSS
THE REGION THROUGH EARLY WEDNESDAY MORNING...WITH SOME LIGHT
ACCUMULATIONS POSSIBLE OVER CENTRAL AND NORTH CENTRAL WISCONSIN.
OTHERWISE...THE UPPER LOW STARTS TO MOVE OUT WED AFTERNOON...AND
SHOULD SEE IMPROVING CONDITIONS START TO PUSH INTO THE REGION BY
THE EVENING HOURS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......KURIMSKI
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
1245 AM EST FRI DEC 4 2015
.AVIATION...
ISOLATED TO SCATTERED SHOWERS WILL CONTINUE OVER ALL OF THE TAF
SITES THROUGH FRIDAY. THE CEILING AND VIS WILL BE CAPABLE OF
FALLING DOWN INTO THE MVFR CONDITIONS WITH THE PASSAGE OF THE
SHOWERS. THE ONLY EXCEPTION TO THIS IS THAT KAPF TAF SITE WILL
REMAIN IN THE IFR CONDITIONS FOR THE CEILINGS THROUGH THE EARLY
MORNING HOURS.
THE WINDS WILL BE MAINLY LIGHT AND VARIABLE OVER THE EAST COAST
TAF SITES EARLY THIS MORNING BEFORE BECOMING NORTHEAST AROUND 10
KNOTS FOR THE DAY HOURS OF FRIDAY. FOR KAPF TAF SITE...THE WINDS
WILL REMAIN NORTHEAST AROUND 10 KNOTS THIS MORNING INTO FRIDAY DAY
HOURS.
&&
.UPDATE...54/BNB
.PREV DISCUSSION... /ISSUED 659 PM EST THU DEC 3 2015/
UPDATE...
FLOOD WATCH WAS ISSUED FOR ALL OF MIAMI-DADE AND BROWARD COUNTIES.
HEAVY RAINFALL IS EXPECTED WITH SHOWERS AND THUNDERSTORMS NOW
MOVING NORTHEAST THIS EVENING. ADDITIONAL HEAVY RAIN WILL DEVELOP
OVERNIGHT AND THROUGH FRIDAY NIGHT ACROSS OF ALL OF SOUTH FLORIDA,
WHICH WILL EXACERBATE CONDITIONS, AS A STALLING COLD FRONT
INTERACTS WITH DEEP TROPICAL MOISTURE. THE FLOOD WATCH MAY NEED TO
BE EXPANDED NORTH AND WEST WITH FUTURE UPDATES.
&&
AVIATION...
SHOWERS AND STORMS ASSOC WITH LINE NOW MOVING NORTHEAST WILL
AFFECT MIA/OPF/TMB IN THE NEXT FEW HOURS. ADDITIONAL HVY SHOWERS
AND SOME THUNDERSTORMS MAY DEVELOP THROUGH THE TAF PERIOD, AS DEEP
TROPICAL MOISTURE INTERACTS WITH A STALLING COLD FRONT. SOME
IFR/MVFR VIS/CIGS CONDS ARE POSSIBLE AS THIS LINE MOVES THROUGH
THE REGION THIS EVENING WITH GUSTS TO 35 KTS.
&&
PREV DISCUSSION... /ISSUED 332 PM EST THU DEC 3 2015/
DISCUSSION...
STEADY STREAM OF HEAVY SHOWERS AND EMBEDDED THUNDERSTORMS
FROM CUBA INTO THE KEYS, HAVE HAD A DIFFICULT TIME HOLDING
TOGETHER INTO THE PENINSULA THIS AFTERNOON. DESPITE THIS NEAR TERM
MODELS, ESPECIALLY THE HRRR CONTINUE TO FORECAST THESE CLUSTERS
EVENTUALLY ENTERING SOUTH FLORIDA LATE THIS AFTERNOON. THE HRRR
HAS BEEN FAR TOO AGGRESSIVE THIS AFTERNOON, SO SKEPTICAL OF THIS
ARRIVAL TIME. ABUNDANT CLOUDS HAVE ALSO PREVENTED ANY DEVELOPMENT
DUE TO DAYTIME HEATING SO FAR. UNDER THIS REGIME, TYPICALLY
OFFSHORE HVY SHOWERS AND THUNDERSTORMS HAVE MUCH BETTER SUCCESS
CROSSING LAND DURING THE EVENING AND OVERNIGHT HOURS. HOWEVER,
STILL CAN`T RULE OUT DEVELOPMENT DURING THE DAYTIME HOURS WITH THE
EAST COAST SEABREEZE POTENTIALLY LEADING TO ENOUGH SURFACE
CONVERGENCE/LIFT FOR WET WEATHER ALONG THE EAST COAST METRO. THIS
SEEMS TO BE OCCURRING IN BROWARD/FLL/FXE ATTM AND PARTS OF
INTERIOR MIAMI-DADE.
OVERALL, SOME CHANGES IN THE MODELS. STRONGER WINDS FORECASTED
BY THE MODELS TO AFFECT ALL OF THE EAST COAST AND ATLANTIC
WATERS, NOW ONLY MAKE IT TO PALM BEACH COUNTY. THIS MAY INDICATE
THAT THE WEAKENING COLD FRONT MAY NOT MAKE IT AS FAR SOUTH AS
PREVIOUSLY THOUGHT. SURFACE HIGH PRESSURE IS CENTERED A LITTLE
FURTHER NORTH THROUGH THE MIDDLE ATLANTIC WHICH LEADS TO LESS OF A
PRESSURE GRADIENT ALONG EXTREME SOUTH FL. THUS THERE IS A
DEVELOPING TREND TOWARDS THE HEAVIEST RAINFALL OCCURRING OVER THE
NORTHERN HALF OF THE FORECAST AREA, AS HEAVIEST QPF FROM THE
GFS/ECMWF HAS SHIFTED NORTH. REGARDLESSS, CAN`T PUT MUCH STOCK IN
RUN TO RUN VARIANCES, SO THE HEAVY RAIN THREAT CONTINUES FOR ALL
OF SOUTH FLORIDA.
FOR TONIGHT AND THE FIRST HALF OF FRIDAY, ADDITIONAL FORCING
PROVIDED BY A FEW MIDLEVEL DISTURBANCES AND MORE FAVORABLE
ORIENTATION OF THE UPPER JET, MAY BE THE EXTRA BOOST NEEDED TO
SPARK DEVELOPMENT. WIND FIELD REMAINS FAVORABLE FOR TRAINING AND
BACKBUILDING, ALSO LLVL HELICITY IS FAVORABLE FOR STRONGER STORMS.
WITH THE LACK OF ACTIVITY THUS FAR THIS PM, WILL HOLD OFF ON A
FLOOD WATCH AND CONTINUE TO ASSESS LATER THIS PM. WITH THE SLOWER
PROGRESSION OF THE FRONT, THE GFS DOES INDICATE SOME HEAVIER RAIN
REMAINING ACROSS THE SOUTHERN CWA INTO SATURDAY MORNING, WHEREAS
THE ECMWF HAS BACKED OFF. BOTH MODELS INDICATE A MIDLEVEL
DISTURBANCE CROSSING THE FL STRAITS AND KEYS, CLIPPING EXTREME SE
FL AROUND 6Z SAT. TOUGH TO ASCERTAIN HOW MUCH QPF FROM BOTH MODELS
ARE BEING INFLUENCED BY CONVECTIVE FEEDBACK. STRONGER MIDLEVEL SW
FLOW DOES SEEM TO END FRIDAY EVENING, WHICH WOULD SEEM TO CUTOFF
THE TRANSPORT OF ANOMALOUS MOISTURE ACROSS THE REGION, ALTHOUGH
PWATS WILL STILL BE ELEVATED. BY SATURDAY PM WINDS BECOME EASTERLY
THROUGH H85 AND ONSHORE FLOW WILL BE RESPONSIBLE FOR SHOWERS ALONG
THE EAST COAST. A SIMILAR SETUP IS EXPECTED ON SUNDAY.
DIFFUSE BOUNDARY WAVERS OVER SOUTH FL THROUGH MONDAY. INTO
MIDWEEK, A STRONGER COLD FRONT MOVING THROUGH THE SOUTHEAST CONUS
MAY FINALLY SHOVE THE WEAK BOUNDARY SOUTH USHERING IN DRIER AIR
WITH DEWPOINTS FALLING INTO THE MIDDLE 50S ACROSS THE
INTERIOR/LAKE REGION. HOWEVER, THE GFS IS FASTER WITH THIS
PROGRESSION WHEREAS THE ECMWF LAGS, WITH A WETTER FORECAST FOR
WEDNESDAY. THE GFS IS ALSO MUCH COOLER BEHIND THIS FRONT THAN THE
ECMWF
MARINE...
NUMEROUS SHOWERS AND SOME STRONGER THUNDERSTORMS EXPECTED AS A
WEAK COLD FRONT STALLS INTO SATURDAY AM. LATEST GUIDANCE
INDICATES THAT SMALL CRAFT ADV LEVEL WINDS MAY ONLY MAKE TO THE
ATLANTIC WATERS OFF PALM BEACH COUNTY. WIND SPEEDS MAY STAY AROUND
10 KTS FARTHER SOUTH. WAVE HEIGHTS ALONG THE GULF STREAM THOUGH
ARE STILL EXPECTED TO BE 7 FT AND ABOVE, HIGHEST OFFSHORE PALM
BEACH COUNTY. A WEAK TO MODERATE SWELL WILL ROLL DOWN THE EAST
COAST SAT AND SAT NIGHT. WAVES SUBSIDE SUNDAY NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 74 80 74 83 / 60 70 50 50
FORT LAUDERDALE 69 79 71 83 / 80 70 50 50
MIAMI 71 81 71 83 / 80 70 50 50
NAPLES 68 82 69 84 / 40 30 30 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH THROUGH SATURDAY MORNING FOR FLZ071>074-172>174.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...54/BNB
LONG TERM....21/KM
AVIATION...54/BNB
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
328 AM CST FRI DEC 4 2015
.SHORT TERM...(Today)
ISSUED AT 328 AM CST FRI DEC 4 2015
Persistent area of low clouds continues to blanket locations east of
the I-55 corridor early this morning. 09z/3am obs also show
widespread dense fog across this area, prompting the issuance of a
Dense Fog Advisory along/east of a Bloomington...to Decatur...to
Taylorville line. With high pressure centered over the Ohio River
Valley, very light S/SW low-level flow has been noted across the
northern half of the CWA: however, winds on the back side of the
high are beginning to take on a S/SE component across south-central
Illinois. IR satellite imagery is showing the low clouds/fog
inching westward just south of Taylorville, with the latest HRRR
suggesting this moisture might curl northward into the Springfield
and Lincoln areas in the next few hours. Will keep an eye on
satellite trends to see if this comes to pass and advisory needs to
be expanded westward to I-55. Due to the low sun angle and only
light low-level flow, fog will be slow to dissipate today. In fact,
HRRR suggests the far E/NE CWA near the Indiana border may remain
overcast for much of the day. Have extended the Dense Fog Advisory
until 17z/11am, but have kept skies mostly cloudy along and
northeast of a Champaign to Paris line until mid to late afternoon.
The evolution of the fog/clouds will have a big impact on high
temperatures. Based on expected trends, have kept readings coolest
in the lower 40s near Danville and Paris, with highs reaching the
upper 40s to around 50 elsewhere.
&&
.LONG TERM...(Tonight through Thursday)
ISSUED AT 328 AM CST FRI DEC 4 2015
While the HRRR and Rapid Refresh have generally done a good job with
the low clouds/fog this morning, the NAM and especially the GFS have
not. In fact, GFS soundings indicate mostly clear skies and
unrestricted visbys today! As a result, am very skeptical about
forecast soundings from both models tonight. The GFS is again
clear: however, the NAM hints at low-level saturation and possible
fog. The high pressure center currently near Evansville, Indiana is
expected to shift into southern Ohio tonight, with the corresponding
ridge axis extending southwestward into the Ozarks. This will
result in the lightest winds across the E/SE CWA, with only a light
S/SW flow further north and west. Given persistent weather pattern,
have decided to include patchy fog mention along/southeast of a
Champaign to Taylorville line once again tonight. Once any morning
fog burns off, mostly sunny skies will prevail on Saturday. Thanks
to a good deal of sunshine and light southerly winds, afternoon high
temperatures will climb at least 10 degrees above normal for this
time of year into the lower 50s.
00z Dec 4 models are still having difficulty with the exact timing
and track of the next approaching short-wave early next week. The
ECMWF is about 6-12 hours faster with the wave than the GFS,
bringing it across central Illinois Sunday afternoon. Meanwhile,
the GFS is more amplified and slower, tracking the feature across
the area Sunday night into Monday. Run-to-run consistency remains
poor with both models, but will stick with the slightly more stable
GFS here. As synoptic lift increases ahead of the wave, clouds will
be on the increase on Sunday. The airmass will initially be quite
dry due to the presence of the strong surface ridge early in the
period, so moisture will remain limited. As a result, will only
feature a slight chance PoP for rain across the W/SW CWA Sunday
afternoon, then mainly across the S/SE Sunday night. These low
chance PoPs may need to be extended into Monday as well if the GFS
verifies. After that, models bring a series of ill-defined weak
short-waves across the CONUS through next week. Pinning down the
exact timing of these features within the zonal flow pattern will be
difficult. Given this fact and the overall lack of deep-layer
moisture, will continue with a mild and dry forecast through the
remainder of the extended.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday night)
ISSUED AT 1141 PM CST THU DEC 3 2015
Challenging forecast, especially for BMI/DEC and possibly CMI.
Conditions have dropped to VLIFR with vis below 3/4sm and cigs
below 500ft. Believe there will be some fluctuations with the
cig/vis for couple of hours at BMI and DEC but then think they
will both go down to 1/4sm FG and cigs around 100-200 ft for most
of the night and then gradually improve during the morning hours.
SPI and PIA should remain clear but have some light fog on and off
late tonight through early tomorrow morning. CMI will remain
cloudy all night with some light fog as well. Cloudy/foggy sites
will see improvement during the afternoon and should become clear
during that time frame. Additional fog looks possible tomorrow
night, so have TEMPO group at all sites for light fog around 3sm.
Winds will be out of the south to southwest remainder of the night
and then become southerly tomorrow. Speeds should be lighter with
high pressure building into the area, but stronger winds see at
BMI where the worst vis is located at.
&&
.ILX Watches/Warnings/Advisories...
Dense Fog Advisory until 11 AM CST this morning for ILZ038-
043>046-052>057-061>063-066>068-071>073.
&&
$$
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
314 AM EST FRI DEC 4 2015
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 310 PM EST THU DEC 3 2015
DRY AND WARMER WEATHER WILL OCCUR THROUGH THE WEEKEND AS HIGH PRESSURE
OVER THE MIDDLE MISSISSIPPI VALLEY MOVES EAST ACROSS THE OHIO VALLEY
LATE TONIGHT AND FRIDAY AND TO SOUTHERN NEW ENGLAND OVER THE WEEKEND.
AN UPPER TROUGH WILL MOVE OUR WAY SUNDAY NIGHT AND MONDAY. BUT AT THE
MOMENT MODELS INDICATE MORE CLOUDS...BUT ONLY SLIGHT CHANCE OF SHOWERS
SOUTH AROUND SUNDAY NIGHT. SLIGHTLY WARMER AND DRY WEATHER WILL OCCUR
NEXT WEEK AS HIGH PRESSURE BUILDS ALONG THE ATLANTIC COAST.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 1012 PM EST THU DEC 3 2015
THERE WILL BE A SHARP GRADIENT BETWEEN TOTAL CLOUD COVER AND CLEAR
SKIES TONIGHT. HAVE ADJUSTED SKY GRIDS IN LINE WITH HRRR LOW LEVEL
MOISTURE PROGS. CLOUD HAS BEEN TRYING TO ERODE AT THE EDGES ALL
EVENING BUT VERY SLOW TO DO SO. ADJUSTED MIN TEMPS ACCORDINGLY AS
WELL...WITH COOLEST TEMPS LIKELY IN THE SOUTH UNDER CLEAR SKIES.
PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 310 PM EST THU DEC 3 2015
SATELLITE INDICATES A LARGE AREA OF STRATUS OVER NORTH AND CENTRAL
SECTIONS...WHILE MOSTLY SUNNY SKIES HAVE CONTINUED ACROSS OUR SOUTH.
THE STATUS HAS BEEN CLEARING OVER WESTERN ILLINOIS....WHILE IT HAS
INCREASED A LITTLE ACROSS INDIANA.
EXPECT SOME CLEARING ACROSS ILLINOIS NEXT SEVERAL HOURS. HOWEVER RUC AND
NAM MODEL INDICATES POSSIBLE REDEVELOPMENT OF STRATUS AND FOG OVER
NORTH AND CENTRAL SECTIONS LATER TONIGHT. FOR NOW WILL KEEP SOME STRATUS
OVER NORTH AND CENTRAL SECTIONS OVERNIGHT...WHICH WOULD MINIMIZE THE
THREAT OF FOG. EVEN IF CLOUDS CLEAR...MODELS INDICATE SOME LOW LEVEL
SHEAR WHICH WOULD FAVOR STRATUS OVER FOG. SO FOR NOW WILL LEAVE OUT MENTION
OF FOG AS PARAMETERS ARE VERY IFFY. OVERNIGHT LOWS WILL BE IN THE MIDDLE
TO UPPER 20S WHICH IS CLOSE TO A MOS BLEND.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
ISSUED AT 310 PM EST THU DEC 3 2015
DRY AND WARMER WEATHER WILL OCCUR THIS WEEKEND AS HIGH PRESSURE
MOVES ON TO THE EAST AND MODELS BUILD AN UPPER RIDGE OVER THE
EASTERN U.S. MODEL SOUNDINGS INDICATE MOSTLY CLEAR SKIES THROUGH
SATURDAY NIGHT AND THEN INCREASING CLOUDS SUNDAY AS AN UPPER TROUGH
MOVES OUR WAY.
MOST MODELS KEEP US DRY THROUGH SUNDAY AFTERNOON...WHILE THE EURO
INDICATES TRACE PRECIP AMOUNTS WEST AND SOUTH LATE SUNDAY. WILL GO
WITH CONSENSUS AND KEEP EVERYTHING DRY THROUGH SUNDAY. HIGHS WILL
BE IN THE UPPER 40S TO LOWER 50S FRIDAY AND SUNDAY AND IN THE LOWER
TO MIDDLE 50S SATURDAY. LOWS WILL BE IN THE UPPER 20S TO AROUND 30
FRIDAY NIGHT AND IN THE LOWER 30S SATURDAY NIGHT. WENT SLIGHTLY ABOVE
A MOS BLEND ON HIGHS WITH SOME SUN AND WARM ADVECTION. OTHERWISE...STAYED
CLOSE TO A MOS BLEND ON LOWS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 314 AM EST FRI DEC 4 2015
UPPER LEVEL FLOW WILL REMAIN QUASI-ZONAL THROUGHOUT MUCH OF NEXT
WEEK...WITH MILD AND MAINLY DRY WEATHER CONTINUING. OVERALL MODEL
GUIDANCE EXHIBITING POOR RUN TO RUN CONSENSUS AS A FEW WEAK WAVES
ALOFT EJECT OUT OF THE UPPER ENERGY MOVING INTO THE PACIFIC
NORTHWEST. PLENTY OF UNCERTAINTY ON HOW AND IF THESE WAVES WILL
IMPACT WEATHER ACROSS THE REGION WHICH RESULTS IN A LOW
CONFIDENCE FORECAST FOR THE EXTENDED PERIOD AT THIS TIME.
WEAK DISTURBANCE ALOFT PASSING THROUGH THE OHIO VALLEY SUNDAY
NIGHT WILL BE MOVING AWAY TO THE EAST ON MONDAY WITH ANY LIGHT
PRECIPITATION DEPARTING WITH IT. MODEL SOUNDINGS AND RH PROGS
SUGGESTIVE OF LINGERING CLOUDS FOR MONDAY IN WAKE OF THE SYSTEM.
SURFACE HIGH PRESSURE WILL RETURN THROUGH MIDWEEK WITH PARTLY
CLOUDY SKIES. SOME HINTS OF AN UPPER WAVE PASSING THROUGH THE
LOWER GREAT LAKES AND OHIO VALLEY WEDNESDAY INTO THURSDAY BUT AS
MENTIONED ABOVE...OPERATIONAL RUNS ARE OUT OF SYNC WITH LITTLE
SUPPORT FROM THE INDIVIDUAL ENSEMBLE MEMBERS. WILL MAINTAIN DRY
CONDITIONS THROUGH THURSDAY AS A RESULT AND CONTINUE TO MONITOR.
EASTWARD PROGRESSION OF A BROAD UPPER TROUGH INTO THE CENTRAL U S
BY NEXT WEEKEND AS ENERGY ALOFT PUSHES ONTO THE WEST COAST LENDS
TO HIGHER CONFIDENCE IN A MORE ACTIVE WEATHER PATTERN COMMENCING
ACROSS THE REGION BEYOND THE 7 DAY PERIOD NEXT WEEKEND INTO THE
FOLLOWING WEEK. CERTAINLY SOMETHING TO WATCH OVER THE NEXT SEVERAL
DAYS.
&&
.AVIATION /DISCUSSION FOR THE 040900Z TAF UPDATE/...
ISSUED AT 314 AM EST FRI DEC 4 2015
STRATUS HAS EXPANDED BACK SOUTHEAST ACROSS THE REGION EARLY THIS
MORNING AS ANTICIPATED. EXPECT ALL SITES TO BE IMPACTED THROUGH
DAYBREAK WITH A SHALLOW BUT SHARP INVERSION NOTED ON MODEL
SOUNDINGS TO LINGER INTO MID MORNING. LOWERED CEILINGS TO CLOSER
TO 500FT BASED ON CURRENT OBS AND DELAYED SCATTERING OF CLOUDS
UNTIL AFTER DAYBREAK AT ALL SITES. WILL CONTINUE TO MONITOR BUT
NOT OUT OF THE QUESTION THAT MAY NEED DELAY CLOUD SCATTERING EVEN
FURTHER FOR 12Z TAFS.
06Z DISCUSSION FOLLOWS.
LATEST SATELLITE LOOP INDICATES AREA OF CEILINGS 008 AGL-015 OVER PARTS OF
NORTHERN AND CENTRAL INDIANA IS BEGINNING TO EXPAND AGAIN DUE TO NOCTURNAL
COOLING AND A STOUT INVERSION BELOW 015 AS SEEN ON THIS EVENING/S UPPER AIR.
AS A RESULT...IT APPEARS DOUBTFUL THESE CEILINGS WILL SCATTER OUT BEFORE
SUNRISE AND MAY LINGER WELL INTO THE DAYLIGHT HOURS ON FRIDAY. WILL BRING
IFR CEILINGS TO ALL THE TAF SITES BY 040800Z AND SCATTER THEM OUT FROM
SOUTHWEST TO NORTHEAST AFTER SUNRISE.
DUE TO THE CLOUD COVER...DO NOT THINK VISIBILITIES WILL GET TOO OUT OF
HAND...BUT MAY SEE SOME IFR VISIBILITY RESTRICTIONS IN THE KBMG AREA
FOR A PERIOD BEFORE THE LOW CEILINGS ADVECT IN.
SURFACE WINDS AT OR BELOW 7 KTS THROUGH 041800Z.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/NIELD
SHORT TERM...JH
LONG TERM....RYAN
AVIATION...JAS/RYAN
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1131 PM EST THU DEC 3 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 310 PM EST THU DEC 3 2015
DRY AND WARMER WEATHER WILL OCCUR THROUGH THE WEEKEND AS HIGH PRESSURE
OVER THE MIDDLE MISSISSIPPI VALLEY MOVES EAST ACROSS THE OHIO VALLEY
LATE TONIGHT AND FRIDAY AND TO SOUTHERN NEW ENGLAND OVER THE WEEKEND.
AN UPPER TROUGH WILL MOVE OUR WAY SUNDAY NIGHT AND MONDAY. BUT AT THE
MOMENT MODELS INDICATE MORE CLOUDS...BUT ONLY SLIGHT CHANCE OF SHOWERS
SOUTH AROUND SUNDAY NIGHT. SLIGHTLY WARMER AND DRY WEATHER WILL OCCUR
NEXT WEEK AS HIGH PRESSURE BUILDS ALONG THE ATLANTIC COAST.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 1012 PM EST THU DEC 3 2015
THERE WILL BE A SHARP GRADIENT BETWEEN TOTAL CLOUD COVER AND CLEAR
SKIES TONIGHT. HAVE ADJUSTED SKY GRIDS IN LINE WITH HRRR LOW LEVEL
MOISTURE PROGS. CLOUD HAS BEEN TRYING TO ERODE AT THE EDGES ALL
EVENING BUT VERY SLOW TO DO SO. ADJUSTED MIN TEMPS ACCORDINGLY AS
WELL...WITH COOLEST TEMPS LIKELY IN THE SOUTH UNDER CLEAR SKIES.
PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 310 PM EST THU DEC 3 2015
SATELLITE INDICATES A LARGE AREA OF STRATUS OVER NORTH AND CENTRAL
SECTIONS...WHILE MOSTLY SUNNY SKIES HAVE CONTINUED ACROSS OUR SOUTH.
THE STATUS HAS BEEN CLEARING OVER WESTERN ILLINOIS....WHILE IT HAS
INCREASED A LITTLE ACROSS INDIANA.
EXPECT SOME CLEARING ACROSS ILLINOIS NEXT SEVERAL HOURS. HOWEVER RUC AND
NAM MODEL INDICATES POSSIBLE REDEVELOPMENT OF STRATUS AND FOG OVER
NORTH AND CENTRAL SECTIONS LATER TONIGHT. FOR NOW WILL KEEP SOME STRATUS
OVER NORTH AND CENTRAL SECTIONS OVERNIGHT...WHICH WOULD MINIMIZE THE
THREAT OF FOG. EVEN IF CLOUDS CLEAR...MODELS INDICATE SOME LOW LEVEL
SHEAR WHICH WOULD FAVOR STRATUS OVER FOG. SO FOR NOW WILL LEAVE OUT MENTION
OF FOG AS PARAMETERS ARE VERY IFFY. OVERNIGHT LOWS WILL BE IN THE MIDDLE
TO UPPER 20S WHICH IS CLOSE TO A MOS BLEND.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
ISSUED AT 310 PM EST THU DEC 3 2015
DRY AND WARMER WEATHER WILL OCCUR THIS WEEKEND AS HIGH PRESSURE
MOVES ON TO THE EAST AND MODELS BUILD AN UPPER RIDGE OVER THE
EASTERN U.S. MODEL SOUNDINGS INDICATE MOSTLY CLEAR SKIES THROUGH
SATURDAY NIGHT AND THEN INCREASING CLOUDS SUNDAY AS AN UPPER TROUGH
MOVES OUR WAY.
MOST MODELS KEEP US DRY THROUGH SUNDAY AFTERNOON...WHILE THE EURO
INDICATES TRACE PRECIP AMOUNTS WEST AND SOUTH LATE SUNDAY. WILL GO
WITH CONSENSUS AND KEEP EVERYTHING DRY THROUGH SUNDAY. HIGHS WILL
BE IN THE UPPER 40S TO LOWER 50S FRIDAY AND SUNDAY AND IN THE LOWER
TO MIDDLE 50S SATURDAY. LOWS WILL BE IN THE UPPER 20S TO AROUND 30
FRIDAY NIGHT AND IN THE LOWER 30S SATURDAY NIGHT. WENT SLIGHTLY ABOVE
A MOS BLEND ON HIGHS WITH SOME SUN AND WARM ADVECTION. OTHERWISE...STAYED
CLOSE TO A MOS BLEND ON LOWS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 240 PM EST THU DEC 3 2015
ENSEMBLES BRING AN UPPER WAVE ACROSS THE AREA SUNDAY NIGHT AS A WEAK
SURFACE SYSTEM SLIDES EAST ACROSS THE TENNESSEE VALLEY. MOISTURE
WILL BE LIMITED...HOWEVER THE FORCING IS ENOUGH TO CONTINUE TO CARRY
WEAK CHANCES OF RAIN SHOWERS ACROSS THE SOUTHERN TIER.
WEAK RIDGING WILL PREVAIL THROUGHOUT MOST OF THE EXTENDED WITH DRY
CONDITIONS AND WARMER THAN NORMAL TEMPERATURES THROUGHOUT NEXT
WEEK.
&&
.AVIATION /DISCUSSION FOR THE 040600Z TAFS/...
ISSUED AT 1131 PM EST THU DEC 3 2015
LATEST SATELLITE LOOP INDICATES AREA OF CEILINGS 008 AGL-015 OVER PARTS OF
NORTHERN AND CENTRAL INDIANA IS BEGINNING TO EXPAND AGAIN DUE TO NOCTURNAL
COOLING AND A STOUT INVERSION BELOW 015 AS SEEN ON THIS EVENING/S UPPER AIR.
AS A RESULT...IT APPEARS DOUBTFUL THESE CEILINGS WILL SCATTER OUT BEFORE
SUNRISE AND MAY LINGER WELL INTO THE DAYLIGHT HOURS ON FRIDAY. WILL BRING
IFR CEILINGS TO ALL THE TAF SITES BY 040800Z AND SCATTER THEM OUT FROM
SOUTHWEST TO NORTHEAST AFTER SUNRISE.
DUE TO THE CLOUD COVER...DO NOT THINK VISIBILITIES WILL GET TOO OUT OF
HAND...BUT MAY SEE SOME IFR VISIBILITY RESTRICTIONS IN THE KBMG AREA
FOR A PERIOD BEFORE THE LOW CEILINGS ADVECT IN.
SURFACE WINDS AT OR BELOW 7 KTS THROUGH 041800Z.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/NIELD
SHORT TERM...JH
LONG TERM...SMF
AVIATION...JAS
AREA FORECAST DISCUSSION
National Weather Service Paducah KY
213 AM CST FRI DEC 4 2015
.UPDATE...
Issued at 213 AM CST FRI DEC 4 2015
Just issued a Dense Fog Advisory for parts of the WFO PAH forecast
area until 11 am CST. Had considered a Freezing Fog Advisory, but
temperatures should rise above freezing between 14z-15z (8-9 am
CST) today. To address the freezing component, emphasized the
development of black ice, given the sub-freezing temperatures
already in place across the WFO PAH forecast area.
Frost has already been deposited across most areas from the early
evening, so further condensation is likely along and the the west
and north of the surface ridge axis overnight and through the
morning. Given the decent inversion aloft, it will take some time
for insolation (sunshine) to erode the edges of the fog layer
inward until 17z (11 am CST) at the latest.
The HRRR and SREF visibility guidance values for fog are
initializing fairly well. May have went out on a limb for
including Southeast Missouri in the Dense Fog Advisory , but
visibility trends continue to slowly move downward, so may see
criteria level visibilities no later than 10z-11z in that area.
&&
.SHORT TERM...(This evening through Saturday night)
Issued at 233 PM CST THU DEC 3 2015
An analysis of the morning and modeled sounding data reveals a
strong inversion from about 2500 FT to about 6500 FT AGL, and this
has kept the small riboon of clouds below 2000 FT from burning
off. These clouds will continue to scrape our northern tier border
counties into the early evening, and otherwise, clear skies will
abound. This will enable another night of good radiational cooling
to allow Lows to dip into the 20s again tonight.
Tmrw, the High pressure center nudges eastward across the Ohio
river valley, underneath the High aloft. Easterlies in the lower
trop will cease the deeper cold advection and result in a warming
to around 50, despite the cold start.
Friday night and Saturday sees the High(s) move further east,
allowing light return flow southerlys to begin again. Temps will
nudge upwards a couple or three degrees from the previous days
readings then...returning closer to norms for this time of year.
.LONG TERM...(Sunday through Thursday)
Issued at 233 PM CST THU DEC 3 2015
Sfc winds will be out of the south by Sun ahead of a fast-moving mid
level shrtwv trof that is progged by the med range models to dive
into the central Plains and then ewd through the PAH forecast area
late in the weekend. The odd model out continues to be the GFS (and
its ensemble means), which has a slower, wetter, and farther south
solution with the trof/low. The UKMET continues to show the feature
as an open wave, and appears the fastest. Other med range models
have something in between.
Deep moist return flow appears very limited with this feature, and
thus moisture will be limited above about 850 mb. Currently, we are
forecasting rainfall amounts a tenth of an inch or less, mainly
behind the sfc cold front. Relatively mild conditions will prevail
behind the front, as the new airmass will be of Pacific origin.
The 12Z ECMWF model, and to a lesser degree, the GFS, suggest the
possibility that one of the ripples in the wavy mid level flow later
in the week may produce pcpn in a similar way (not shown
significantly in the initialization blend). For now we left the
forecast dry, and will see what later model runs reveal.
&&
.AVIATION...
Issued at 1032 PM CST THU DEC 3 2015
May have to consider MVFR vsbys at the terminals through the
early a.m. Other nearby sights at cross over with calm winds and
clear skies the rule. Otherwise high pressure will result in cloud
free skies and light winds Friday through Friday evening.
&&
.PAH Watches/Warnings/Advisories...
IL...Dense Fog Advisory until 11 AM CST this morning for ILZ075>078-
080>090-092-093.
MO...Dense Fog Advisory until 11 AM CST this morning for MOZ076-086-
087-100-107>111-114.
IN...Dense Fog Advisory until 11 AM CST this morning for INZ081-082-
085>087.
KY...Dense Fog Advisory until 11 AM CST this morning for KYZ018.
&&
$$
UPDATE...Smith
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
445 AM EST FRI DEC 4 2015
.AVIATION...
TIMING THE EXIT OF THE LOW CLOUDS WILL REMAIN THE MOST CHALLENGING
ASPECT OF THE TAFS. A LOWERING INVERSION HAS LED TO AN EXTENSIVE
AREA OF IFR CEILINGS ACROSS NRN INDIANA AND FAR SW LOWER MI...ON THE
DOORSTEP OF METRO DETROIT AS OF 0930Z. THE INFLUENCE OF THE WEST-
SOUTHWEST FLOW ACROSS LAKE MI MAY HOLD THE INVERSION BASE UP A
LITTLE HIGHER...THUS KEEPING CIGS ON THE LOW END OF THE MVFR RANGE.
WARMER AND DRIER LOW LEVEL AIR WILL SLOWLY WORK FROM W TO E ACROSS
THE AREA LATE THIS MORNING INTO THE AFTERNOON. THE LOW LEVEL FLOW
WILL ALSO BECOME MORE ANTICYCLONIC DURING THIS TIME PERIOD. THIS
WILL PLACE THE MOST PROBABLE TIME PERIOD FOR CLEARING DURING THE 17Z
TO 20Z TIME FRAME. THERE HAS HOWEVER BEEN SOME FAIRLY SIGNIFICANT
BREAKS ACROSS NE LOWER MI...AN AFFECT OF SOME ADDED DOWNSLOPE.
CONSIDERING THE VERY SHALLOW NATURE OF THE MOISTURE. THIS DOWNSLOPE
MAY LEAD TO MORE BREAKS IN AND AROUND MBS MUCH EARLIER. ASIDE FROM
THE CLOUDS...WINDS HAVE ACTUALLY INCREASED OVERNIGHT /GUSTING UP TO
20 KNOTS AT TIMES/. THERE WILL BE A SLOW BUT STEADY DECREASE IN THE
WINDS DURING THE MORNING AND AFTERNOON AS THE GRADIENT WEAKENS.
FOR DTW....ANY CLEARING AT METRO PRIOR TO 18Z WILL NEED SOME MORNING
BREAKS TO DEVELOP OVER NRN IND/SW LOWER MI. RECENT SATELLITE TRENDS
SUGGEST THIS IS NOT GOING TO HAPPEN. IN FACT...THE HRRR KEEPS THE
CLOUDS IN THROUGH 21Z. WHILE CERTAINLY POSSIBLE...AT THIS TIME THE
CONCERNS OF EARLIER CLEARING UPSTREAM SUGGESTS ONLY PUSHING THE
CLEARING BACK TO 19Z.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILINGS BELOW 5000 FEET THIS MORNING. LOW CONFIDENCE ON
TIMING OF CLEARING THIS AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 237 AM EST FRI DEC 4 2015
DISCUSSION...
A LARGE AREA OF SURFACE HIGH PRESSURE WILL MAINTAIN QUIET WEATHER
THROUGH THE WEEKEND AS OVERALL MID LATITUDE FLOW REMAINS INNOCUOUS
FOR EARLY DECEMBER WITH AN EVEN WEAKER SUB-TROPICAL JET LENDING
LITTLE TO NO SUPPORT FOR ANY NOTABLE JET STREAM PHASING INTO EARLY
NEXT WEEK. THIS WILL LEAD TO A LARGELY DRY WEATHER PATTERN. THE NEXT
VERY SMALL CHANCE OF RAIN WILL COME EARLY NEXT WEEK AS A SHORTWAVE
MEANDERS EASTWARD INTO THE OHIO VALLEY. THIS SYSTEM REMAINS CUT OFF
FROM THE MAIN BAND OF WESTERLIES WITH NO INDICATIONS OF PHASING WITH
THE SUB-TROPICAL JET UNTIL IT APPROACHES THE EAST COAST. SO...ANY
PRECIPITATION THAT MAY BRUSH THE AREA IS EXPECTED TO BE TRIVIAL AT
THIS TIME.
FOR TODAY...SKY CONDITIONS WILL BE THE MAIN CHALLENGE AS CLEARING
WITHIN SUBSIDENCE REGION IN WAKE OF PASSING WEAK TROUGH HAS BEEN
SLOW TO OCCUR GIVEN THE REFORMATION OF STRATUS TO THE LEE OF LAKE
MICHIGAN. AS DRIER AIR CONTINUES TO WORK INTO AREA WITH EXPANDING
SURFACE HIGH PRESSURE...STILL EXPECT SKIES TO CLEAR WITH TIME DURING
THE DAY. IT JUST MAY TAKE HALF OR MORE OF THE DAY. THIS WILL HAVE
SOME AFFECT ON TEMPERATURES...ALTHOUGH STEADY WEST TO SOUTHWEST FLOW
WILL ALLOW FOR DECENT MIXING...SO EXPECT HIGHS TO CLIMB INTO THE MID
TO UPPER 40S AS A WEAK WARM AIR ADVECTION PATTERN ENSUES AS UPPER
RIDGING EXPANDS OVER THE AREA.
MILD WEATHER WILL PERSIST THROUGH THE WEEKEND AS THIS RIDGE SLOWLY
PROGRESSES TO THE EAST COAST...BUT AREA REMAINS WITHIN SOUTHWESTERLY
UPPER LEVEL FLOW. EXPECT HIGHS IN THE MID 40S TO AROUND 50 BOTH
DAYS.
WHILE THE ABOVE AVERAGE START TO DECEMBER WILL PERSIST THROUGH MID
TO LATE NEXT WEEK...OVERALL WEATHER PATTERN BECOMES INCREASINGLY
DIFFICULT AS THE MID LATITUDE JET STREAM COMING ONSHORE OVER THE
WESTERN CONUS INCREASES SUBSTANTIALLY WITH TIME NEXT WEEK. COUPLE
THIS WITH AN GRADUAL ENHANCEMENT IN THE SUBTROPICAL JET...AND ANY
SHORTWAVE ENERGY EJECTING INTO THE PLAINS/MIDWEST WILL HAVE A MUCH
BETTER CHANCE OF DEVELOPING INTO A DECENT STORM AS COMPARED TO THE
SHORTER TERM UPPER LEVEL CONDITIONS ACROSS THE CONUS THROUGH THE
WEEKEND.
MARINE...
A TIGHTENING OF THE GRADIENT OVER LAKE HURON THIS MORNING HAS LED TO
SOME GUSTY WEST-SOUTHWEST WINDS...GUSTING OVER 25 KNOTS AT TIMES. A
SURFACE TROUGH AXIS NOW ROTATING ACROSS THE NORTHERN GREAT
LAKES...PASSING ATOP THE NORTHERN PERIPHERY OF STRONG HIGH PRESSURE
CENTERED OVER THE MID MISSISSIPPI VALLEY...IS SUSTAINING THIS GRADIENT.
THIS TROUGH AXIS WILL TRACK EAST OF THE REGION TODAY. THE SURFACE
HIGH WILL THEN EXPAND NORTHWARD INTO THE GREAT LAKES. THIS ALONG
WITH LOW LEVEL WARM AIR ADVANCING ACROSS THE LAKES WILL LEAD TO A
STEADY DECREASING TREND IN WINDS AND WAVES TODAY. THE HIGH WILL
DRIFT TO THE MID ATLANTIC DURING THE COURSE OF THE WEEKEND...PLACING
LAKE HURON WITHIN A SOUTH-SOUTHWESTERLY RETURN FLOW. THE WARM LOW
LEVEL AIR WILL HINDER MIXING POTENTIAL OVER THE LAKES...SO GUSTS ARE
EXPECTED TO REMAIN LARGELY UNDER 20 KNOTS. HIGH PRESSURE WILL EXPAND
BACK ACROSS THE GREAT LAKES EARLY NEXT WEEK...PROVIDING FAIRLY LIGHT
WINDS MONDAY INTO AT LEAST TUESDAY.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...SMALL CRAFT ADVISORY UNTIL 8 AM EST THIS MORNING FOR LHZ421-441.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....SC
DISCUSSION....DG
MARINE.......SC
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
330 AM CST FRI DEC 4 2015
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 325 AM CST FRI DEC 4 2015
MAIN FORECAST CHALLENGE WILL BE TEMPERATURES. GOOD AGREEMENT WITH
MODELS ON MAIN DETAILS.
TEMPERATURES WILL BE THE PRIMARY CHALLENGE THROUGH THE PERIOD
BETWEEN AREAS WITH SNOW COVER VS NO SNOW. OVER A 20 DEGREES SPREAD
IN MAXIMUM TEMPERATURES YESTERDAY BASED JUST ON SNOW COVER. THIS
TREND WILL LIKELY CONTINUE AS LONG AS SNOW COVER EXISTS.
FOR TODAY SURFACE PRESSURE GRADIENT INCREASES FOR BREEZY
CONDITIONS HOWEVER WITH VERY SHALLOW MIXED LAYER STRONGER WINDS
ALOFT NOT LIKELY TO MIX DOWN. WARM COLUMN REMAINS IN PLACE SO MILD
TEMPERATURES TO CONTINUE. DIFFERENCE TODAY FROM YESTERDAY WILL BE
SOUTHERLY VS WESTERLY SURFACE WINDS. A SOUTH WIND COMING ACROSS
SNOW FIELD MAY SOMEWHAT LIMIT TEMPERATURE CLIMB ACROSS SNOW FREE
REGION ACROSS THE NORTHERN FA. MODEL GUIDANCE HAS STRUGGLED WITH
TEMPERATURES AS A RESULT OF SNOW COVER. RUC APPEARED MOST
REALISTIC WITH TEMPERATURES SO GENERALLY FOLLOWED ITS FORECAST.
NORTHERN AREAS MAY STAY JUST SHY OF 50 WITH REMAINDER OF FA
HOLDING IN THE 30S TO AROUND 40.
MIXING WILL HOLD TEMPERATURES UP TONIGHT WITH MINIMUMS AT OR ABOVE
AVERAGE HIGHS FOR THIS TIME OF THE YEAR.
BROAD MID LEVEL TROUGH WILL CROSS THE FA THIS WEEKEND. A WEAK COLD
FRONT WILL CROSS THE REGION SATURDAY. COLUMN LACKING MOISTURE SO A
BIT MORE CLOUD COVER AND WSHFT WILL BE THE ONLY AFFECTS WITH
FROPA. COLUMN COOLER SO TEMPERATURES MAY BE MORE UNIFORM ACROSS
THE FA BUT STILL WELL ABOVE AVERAGE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 AM CST FRI DEC 4 2015
MINIMAL WEATHER IMPACTS WILL CONTINUE REMAINDER OF THE WEEKEND.
WELL ABOVE AVERAGE TEMPERATURES WILL CONTINUE TO WORK ON SHRINKING
EXISTING SNOW PACK. APPEARS TO BE ENOUGH MIXING TO LIMIT NIGHTTIMEFOG
DEVELOPMENT WITH DAY TIME MELTING BUT WILL NEED TO MONITOR.
MODELS INITIALIZED WELL AND CONTINUE TO SHOW A GENERAL BROAD RIDGE
ACROSS THE NRN PLAINS. WITH THE UPPER RIDGE REMAINING IN
PLACE...EXPECT TEMPERATURES TO REMAIN ABOVE NORMAL. HOWEVER...TEMPS
WILL DEPEND ON ANY REMAINING SNOW PACK...AND INDICATIONS ARE IT WILL
CONTINUE TO ERODE...AS HIGH TEMPS LOOK TO BE IN THE UPPER 30S TO LOW
40S THRU THE PERIOD. OTHERWISE...A FEW IMPULSES OF ENERGY WILL
PROPAGATE THRU THE FLOW...BUT WITH A GENERALLY DRY COLUMN DO NOT
ANTICIPATE MUCH IN THE WAY OF PCPN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1143 PM CST THU DEC 3 2015
WINDS WILL BE THE MAIN CONCERN THIS PERIOD AS SOUTHERLY WINDS
BECOME GUSTY BY FRIDAY AFTERNOON. CIRRUS POSSIBLE...WITH VFR
CONDITIONS THROUGH THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...VOELKER
LONG TERM...HOPKINS/VOELKER
AVIATION...TG
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
358 AM EST FRI DEC 4 2015
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE WILL BUILD ACROSS THE EASTERN CONUS
FOR THE WEEKEND AND INTO EARLY NEXT WEEK...SUPPLYING FAIR AND
MILDER WEATHER WITH LIGHT WIND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
LOW LVL MOISTURE TRAPPED BENEATH SHARP INVERSION RESULTING IN
PERSISTENT LOW CLOUDS ACROSS CENTRAL PA EARLY THIS AM. SATL LOOP
AT 06Z INDICATING SOME BREAKS IN THE OVERCAST ACROSS THE LOWER
SUSQ VALLEY AND EXPECT THE CLEARING TREND TO WORK NWRD EARLY THIS
MORNING...AS INVERSION HGT LOWERS. NEAR TERM MDL SOUNDINGS SUPPORT
MCLEAR SKIES FROM KUNV/KAOO EASTWARD BY DAWN...WHILE STRATOCU
LINGERS ACROSS THE ALLEGHENY MTNS.
HAVE ZEROED OUT THE POPS EARLY THIS MORNING...AS MOISTURE LAYER IS
TOO SHALLOW TO SUPPORT PRECIP. HAVE ALSO RAISED MIN TEMPS
OVERNIGHT...GIVEN CLOUD COVER AND PERSISTENT BREEZE. BLEND OF LAMP
AND LATEST HRRR DATA SUPPORT READINGS IN THE 30S AT DAWN.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
NEAR SFC FLOW WILL BECOME ANTICYCLONIC ACROSS THE FCST AREA BY
MIDDAY AS A LARGE SFC HIGH BUILDS NE FROM THE OHIO RIVER VALLEY.
LINGERING...SHALLOW SCT-BKN STRATO CU MAY PERSIST INTO THE
AFTERNOON ACROSS THE NRN MTNS. HOWEVER...EXPECT A DECENT AMOUNT OF
SUNSHINE ELSEWHERE ACROSS CENTRAL AND SOUTHERN PENN AFTER A PARTLY
TO MOSTLY CLOUDY START TO THE DAY.
WINDS WILL BE LESS THAN THURSDAY...BUT SOME WESTERLY GUSTS INTO
THE MID TEENS AREA STILL POSSIBLE.
TEMPS WILL BE A FEW DEG F HIGH THAN THURSDAY ACROSS MUCH OF THE
FCST AREA /WHICH WILL TURN OUT TO BE NEAR TO SLIGHTLY ABOVE
NORMAL/. MAXES ON FRIDAY WILL VARY FROM THE U30S OVER THE HIGHEST
ELEVATIONS TO AROUND 50F IN THE FAR SE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
A SPLIT FLOW PATTERN IS FCST OVER THE LOWER 48 THRU THE MEDIUM
RANGE PERIOD...WITH RATHER MILD TEMPERATURES FOR EARLY DECEMBER
ANTICIPATED AS A PACIFIC AIRMASS MIGRATES FROM WEST TO EAST.
RIDGING AT THE SURFACE AND ALOFT WILL DOMINATE THE REGIONAL
WEATHER PATTERN WITH HIGH CONFIDENCE IN DRY WEATHER THROUGH
MONDAY.
THE KEY FEATURE HEADING INTO THE MIDDLE OF NEXT WEEK WILL BE A
MID LEVEL SYSTEM EVOLVING EASTWARD FROM THE ROCKIES AND POSSIBLY
CUTTING OFF SOMEWHERE BETWEEN TEXAS AND THE OHIO VALLEY. GIVEN THE
LARGE SPREAD AND MEDIUM RANGE MODEL `LIMBO` WILL STAY CLOSE TO
CONTINUITY. CONFIDENCE IS LOW REGARDING PCPN RISK AROUND THE
MIDDLE PART OF NEXT WEEK: A WELL-DEFINED LOW IS FORECAST BY MOST
GUID TO FORM JUST OFF THE EAST COAST AS THE MID LEVEL LOW
INTERACTS WITH TROPICAL MOISTURE. HOWEVER...THE LOW MAY BE FAR
ENOUGH TO THE S/E OF THE STATE TO KEEP IT DRY. ONLY SOME LOW POPS
WILL CONTINUE TO BE MENTIONED - MAINLY FOR THE SE FROM MON NITE-
TUE NIGHT.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH SHARP INVERSION RESULTING IN
PERSISTENT LOW CLOUDS ACROSS CENTRAL PA EARLY THIS AM...WITH MVFR
CIGS IMPACTING CENTRAL MTNS FROM KJST-KAOO-KUNV AND IFR CIGS IN
THE NW MTNS INCLUDING KBFD. SATL LOOP INDICATING SOME BREAKS IN
THE OVERCAST ACROSS THE LOWER SUSQ VALLEY...AND EXPECT THE
CLEARING TREND TO WORK NWRD EARLY THIS MORNING AS INVERSION HGT
LOWERS. NEAR TERM MDL SOUNDINGS SUPPORT MCLEAR SKIES EAST OF
KUNV/KAOO BY DAWN...WHILE STRATOCU LINGERS ACROSS THE ALLEGHENY
MTNS.
THE FAIRLY SHALLOW STRATOCU CLOUDS WILL STAY IN THE IFR RANGE
THROUGH THE MID MORNING HOURS FRIDAY ACROSS THE NW MTNS. MVFR
STRATOCU ACROSS THE CENTRAL RIDGE AND VALLEY REGION WILL ERODE
AROUND 14-15Z...WHILE THE SE WILL SEE PRIMARILY VFR CONDITIONS ON
FRI. BFD WILL IMPROVE TO VFR BY EARLY AFTERNOON.
AS HIGH PRES APPROACHES FROM THE WEST...WINDS WILL REMAIN UP A BIT
OVERNIGHT AT SPEEDS AROUND 8-10KTS...WITH GUSTS TO 15-20 IN
SPOTS. THESE PERSIST INTO LATE MORNING FRI BEFORE DECREASING.
OUTLOOK...
SAT-MON...NO SIG WX EXPECTED.
TUE...CHANCE OF MVFR CIGS MAINLY ACROSS THE SERN 1/2 OF PENN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...FITZGERALD
SHORT TERM...DANGELO/LAMBERT
LONG TERM...GARTNER/STEINBUGL
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
120 AM EST FRI DEC 4 2015
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE WILL BUILD ACROSS THE EASTERN CONUS
FOR THE WEEKEND AND INTO EARLY NEXT WEEK...SUPPLYING FAIR AND
MILDER WEATHER WITH LIGHT WIND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
LOW LVL MOISTURE TRAPPED BENEATH SHARP INVERSION RESULTING IN
PERSISTENT LOW CLOUDS ACROSS CENTRAL PA EARLY THIS AM. SATL LOOP
AT 06Z INDICATING SOME BREAKS IN THE OVERCAST ACROSS THE LOWER
SUSQ VALLEY AND EXPECT THE CLEARING TREND TO WORK NWRD EARLY THIS
MORNING...AS INVERSION HGT LOWERS. NEAR TERM MDL SOUNDINGS SUPPORT
MCLEAR SKIES FROM KUNV/KAOO EASTWARD BY DAWN...WHILE STRATOCU
LINGERS ACROSS THE ALLEGHENY MTNS.
HAVE ZEROED OUT THE POPS EARLY THIS MORNING...AS MOISTURE LAYER IS
TOO SHALLOW TO SUPPORT PRECIP. HAVE ALSO RAISED MIN TEMPS
OVERNIGHT...GIVEN CLOUD COVER AND PERSISTENT BREEZE. BLEND OF LAMP
AND LATEST HRRR DATA SUPPORT READINGS IN THE 30S AT DAWN.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
NEAR SFC FLOW WILL BECOME ANTICYCLONIC ACROSS THE FCST AREA BY
MIDDAY AS A LARGE SFC HIGH BUILDS NE FROM THE OHIO RIVER VALLEY.
LINGERING...SHALLOW SCT-BKN STRATO CU MAY PERSIST INTO THE
AFTERNOON ACROSS THE NRN MTNS. HOWEVER...EXPECT A DECENT AMOUNT OF
SUNSHINE ELSEWHERE ACROSS CENTRAL AND SOUTHERN PENN AFTER A PARTLY
TO MOSTLY CLOUDY START TO THE DAY.
WINDS WILL BE LESS THAN THURSDAY...BUT SOME WESTERLY GUSTS INTO
THE MID TEENS AREA STILL POSSIBLE.
TEMPS WILL BE A FEW DEG F HIGH THAN THURSDAY ACROSS MUCH OF THE
FCST AREA /WHICH WILL TURN OUT TO BE NEAR TO SLIGHTLY ABOVE
NORMAL/. MAXES ON FRIDAY WILL VARY FROM THE U30S OVER THE HIGHEST
ELEVATIONS TO AROUND 50F IN THE FAR SE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
A SPLIT FLOW PATTERN IS FCST OVER THE LOWER 48 THRU THE MEDIUM
RANGE PERIOD...WITH RATHER MILD TEMPERATURES FOR EARLY DECEMBER
ANTICIPATED AS A PACIFIC AIRMASS MIGRATES FROM WEST TO EAST.
RIDGING AT THE SURFACE AND ALOFT WILL DOMINATE THE REGIONAL
WEATHER PATTERN WITH HIGH CONFIDENCE IN DRY WEATHER THROUGH
MONDAY.
THE KEY FEATURE HEADING INTO THE MIDDLE OF NEXT WEEK WILL BE A
MID LEVEL SYSTEM EVOLVING EASTWARD FROM THE ROCKIES AND POSSIBLY
CUTTING OFF SOMEWHERE BETWEEN TEXAS AND THE OHIO VALLEY. GIVEN THE
LARGE SPREAD AND MEDIUM RANGE MODEL `LIMBO` WILL STAY CLOSE TO
CONTINUITY. CONFIDENCE IS LOW REGARDING PCPN RISK AROUND THE
MIDDLE PART OF NEXT WEEK: A WELL-DEFINED LOW IS FORECAST BY MOST
GUID TO FORM JUST OFF THE EAST COAST AS THE MID LEVEL LOW
INTERACTS WITH TROPICAL MOISTURE. HOWEVER...THE LOW MAY BE FAR
ENOUGH TO THE S/E OF THE STATE TO KEEP IT DRY. ONLY SOME LOW POPS
WILL CONTINUE TO BE MENTIONED - MAINLY FOR THE SE FROM MON NITE-
TUE NIGHT.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
UPPER TROUGH AND COLDER AIR ALOFT SUPPORTING SNOW SHOWERS CONTINUE
TO LIFT NE TOWARD NEW ENGLAND TONIGHT. SNOW SHOWERS HAVE
RESUMED...BRINGING LIFR CONDITIONS TO BFD AND MVFR CIGS THROUGH
THE OTHER CENTRAL AND WESTERN TAF SITES. THIS LOW STRATOCU WILL
CONTINUE THROUGH MOST OF THE OVERNIGHT PERIOD...WITH IFR CIGS
POSSIBLE AT JST...MAINLY AFTER 05Z.
THE FAIRLY SHALLOW STRATO CU CLOUDS WILL STAY IN THE IFR RANGE
THROUGH THE MID MORNING HOURS FRIDAY ACROSS THE NRN AND WRN MTNS
OF PENN...AND THEIR BASES WILL EVEN LOWER A FEW HUNDRED FEET.
BKN-OVC STRATO CU ACROSS THE CENTRAL RIDGE AND VALLEY REGION WILL
BE MAINLY MVFR THROUGH 12Z FRI...WHILE THE KMDT AND KLNS AREA SEE
PRIMARILY VFR SCT CLOUDS WITH BRIEF MVFR BKN CIGS POSSIBLE.
A MODERATELY TIGHT PRES GRADIENT IN WAKE OF THE DEPARTING STORM
SYSTEM WILL MAINTAIN GUSTY WNW WINDS IN THE UPPER TEEN TO LOWER 20
KT RANGE THROUGH THE FIRST HALF OF THE EVENING...BEFORE THE WIND
DECREASES SLIGHTLY OVERNIGHT AS HIGH PRES APPROACHES FROM THE
WEST.
EXPECT MAINLY VFR AT MOST LOCATIONS AFTER 15Z FRIDAY...CURRENT
MODELS SHOW BFD IMPROVING TO VFR BY EARLY AFTERNOON.
OUTLOOK...
SAT-MON...NO SIG WX EXPECTED.
TUE...CHANCE OF MVFR CIGS MAINLY ACROSS THE SERN 1/2 OF PENN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...FITZGERALD
SHORT TERM...DANGELO/LAMBERT
LONG TERM...GARTNER/STEINBUGL
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS MIAMI FL
1007 AM EST FRI DEC 4 2015
.UPDATE...
RAIN COVERAGE ACROSS SOUTH FLORIDA IS FINALLY BEGINNING TO
SUBSIDE. WATER VAPOR IMAGERY SHOWING THE DEEPER MOISTURE HAS MOVED
OFFSHORE. THE RAP13 ANALYSIS OF THE UPPER LEVEL WIND SHOWING THE
BEST DIVERGENCE ALOFT HAS MOVED TO THE SOUTHEAST, WHICH
CORRESPONDS TO THE BETTER RAIN COVERAGE, AS WELL AS THE HEAVIER
SHOWERS AND THUNDERSTORMS. THE HRRR HAS BEEN HANDLING THE COVERAGE
FAIRLY WELL AND HAS MOST OF THE RAIN ENDING, EXCEPT FOR SOME
SHOWER ACTIVITY REDEVELOPING IN THE LAKE REGION. HAVE BROUGHT
POPS DOWN SOME, BUT HAVE LEFT LIKELY POPS IN THE FORECAST FOR MOST
OF THE ATLANTIC COASTAL METRO AREAS, ESPECIALLY FROM BROWARD,
NORTH.
&&
.PREV DISCUSSION... /ISSUED 729 AM EST FRI DEC 4 2015/
AVIATION...
WIDESPREAD RAIN AND SHOWERS LOOK TO CONTINUE THROUGH MUCH OF THE
DAY. PERIODS OF SIGNIFICANT RESTRICTIONS ARE POSSIBLE...BUT
MAJORITY OF TIME EXPECT VFR CONDITIONS. EAST WIND AROUND 10 KT
THROUGH THE PERIOD.
PREV DISCUSSION... /ISSUED 400 AM EST FRI DEC 4 2015/
DISCUSSION...
COLD FRONT EARLY THIS MORNING WAS ALIGNED FROM MAINLAND MONROE
COUNTY TO NORTHERN BROWARD COUNTY. THIS FRONT IS FORECAST TO SAG
SLOWLY SOUTHEASTWARD AND BE POSITIONED OFF THE SOUTHEAST FLORIDA
COAST TONIGHT. HIGH PRESSURE BUILDING NORTH OF THE FRONT WILL LEAD
TO INCREASING NORTHEASTERLY WINDS FROM N-S BEHIND THIS FRONT.
DEEP TROPICAL MOISTURE WILL CONTINUE ACROSS BROWARD/MIAMI-DADE
NEAR THE FRONTAL BOUNDARY TODAY-TONIGHT BEFORE DRIER AIR MOVES IN
FROM THE NORTHWEST. GPS MET DATA SHOWS PW AT MIAMI AT AROUND 2.25
INCHES. VERY IMPRESSIVE AND NEAR THE MAXIMUM RECORDED FOR THE
MONTH OF DECEMBER! PW AT BOTH NAPLES AND OKEECHOBEE WAS NEAR 1.9
INCHES. GIVEN THE IMPRESSIVE MOISTURE, THE ATMOSPHERE IS RIPE FOR
HEAVY RAINFALL PRODUCTION NEAR/IN ADVANCE OF THE FRONT OVER MIAMI-
DADE AND BROWARD. WAVES OF LOCALLY HEAVY RAINFALL ARE FORECAST TO
CONTINUE TO MOVE IN FROM THE SOUTHWEST TODAY ACROSS BROWARD/MIAMI-
DADE WITH LESS INTENSITY POINTS NORTH AND WEST. GIVEN RECENT HEAVY
RAINFALL IN SOME LOCALES OVER THE PAST 24 HOURS...ADDITIONAL
LOCALIZED HEAVY RAINFALL (3"+ POSSIBLE) COULD LEAD TO FLOODING AT
SOME LOCALES ACROSS THE MIAMI AND FORT LAUDERDALE METRO AREAS. AS
SUCH...CONTINUED THE FLOOD WATCH FOR BROWARD /MIAMI-DADE THROUGH
SAT MORNING. RAIN INTENSITY IS EXPECTED TO BE LESS POINTS NORTH
AND WEST...SO NO NEED TO EXPAND THE WATCH ELSEWHERE.
A FEW TSTORMS WILL CONTINUE...ESPECIALLY ACROSS THE ATLANTIC
WATERS, BUT POSSIBLE OVER LAND AS WELL TODAY. THE LACK THOUGH OF
APPRECIABLE INSTABILITY IS EXPECTED TO KEEP TSTORMS ORDINARY IN
NATURE WITH LIGHTNING/HEAVY RAIN THE THREATS.
AS WINDS TURN NORTHEAST BEHIND THE FRONT AND MOISTURE LAGS
BEHIND...CONVERGENCE ALONG THE EAST COAST IS FORECAST TO KEEP
SHOWERS GOING, ESPECIALLY ALONG THE COAST WHERE THE HEAVY RAIN
THREAT COULD CONTINUE THROUGH TONIGHT INTO EARLY SATURDAY.
THE FORECAST SUNDAY INTO MID WEEK FEATURES CONTINUED CHANCES OF
SHOWERS AS A NE WIND CONTINUES ALONG WITH SUFFICIENT MOISTURE TO
SUPPORT SHOWERS FOCUSED ALONG THE ATLANTIC COAST...WITH LESSER
CHANCES INLAND AND TO THE GULF COAST. BOTH GFS AND ECMWF SHOW
A SHORTWAVE MOVING ACROSS THE GULF DURING THE MIDDLE PART OF NEXT
WEEK WHICH COULD LEAD TO PERHAPS INCREASED SHOWER ACTIVITY THEN.
TEMPS CONTINUE ABOVE AVERAGE THROUGH NEXT WEEK...AND NO SIGNS OF
ANY SIGNIFICANT COOLING HERE. IN FACT, THE 540DM 1000-500 MB
THICKNESS LINE (OFTEN LOOKED AT FOR RAIN-SNOW LINE), RESIDES IN
CANADA TO THE NORTH OF MINNESOTA FOR MUCH OF NEXT WEEK...VERY
IMPRESSIVE FOR DECEMBER! #ELNINO /GREGORIA
MARINE...
COLD FRONT OVER THE LOCAL WATERS, STRETCHING EARLY THIS MORNING
FROM OFF THE BROWARD COUNTY COAST TO THE GULF WATERS OFF THE
MAINLAND MONROE COUNTY COAST, WILL SAG SLOWLY SOUTHEAST THROUGH
TONIGHT WITH NORTHEASTERLY WINDS INCREASING BEHIND THE FRONT. HIGH
PRESSURE BUILDING NORTH OF THE FRONT WILL RESULT IN A MODERATE TO
FRESH NORTHEAST WIND FLOW PREVAILING THROUGH THE WEEKEND.
A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR THE OFFSHORE GULF
WATERS EFFECTIVE THIS AFTERNOON THROUGH EARLY MONDAY.
A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR THE ATLANTIC WATERS
EFFECTIVE THIS EVENING THROUGH MONDAY MORNING AS GULF STREAM SEAS
BUILD TO 7+ FEET. /GREGORIA
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 78 74 82 76 / 70 40 60 50
FORT LAUDERDALE 77 69 80 72 / 70 50 60 50
MIAMI 78 71 81 73 / 60 50 60 50
NAPLES 76 66 84 68 / 30 30 40 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH THROUGH SATURDAY MORNING FOR FLZ071>074-172>174.
AM...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY
FOR AMZ650-651-670-671.
GM...SMALL CRAFT ADVISORY UNTIL 10 AM EST SUNDAY FOR GMZ676.
&&
$$
SHORT TERM...13/SI
LONG TERM....57/DG
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
825 AM CST FRI DEC 4 2015
.SHORT TERM...
256 AM CST
THROUGH SATURDAY NIGHT...
EARLY THIS MORNING...HIGH PRESSURE IS CENTERED ACROSS THE LOWER
OHIO VALLEY WITH RIDGING EXTENDING ACROSS THE UPPER MIDWEST.
SATELLITE IMAGERY AND AREA OBSERVATIONS SHOWS LOW STRATUS ACROSS
MUCH OF NORTHEAST AND EAST CENTRAL ILLINOIS AND NORTHWEST INDIANA.
WHILE THE BACK EDGE HAS BEEN STEADILY ERODING FROM THE WEST ACROSS
PORTIONS OF FAR NORTHERN ILLINOIS OVERNIGHT...SOUTH OF I-80 THE
STRATUS HAS BEEN SPREADING NORTH...AND LOWERING WITH VISIBILITY
DROPPING BELOW A MILE IN SEVERAL LOCATIONS. GENERALLY LIKE
HRRR/RAP CIG/VSBY TRENDS PARTICULARLY SOUTH OF I-80 WHERE THE
GREATEST THREAT OF AT LEAST SOME PATCHY DENSE FOG APPEARS TO BE
THIS MORNING. WILL CONTINUE TO MONITOR TRENDS CLOSELY AS A DENSE
FOG ADVISORY MAY BE NEEDED FOR SOME AREAS. CLOUD COVER WILL BE
SLOW TO ERODE TODAY...THOUGH THE NORTHWEST HALF OR SO OF THE CWA
SHOULD SEE SUNSHINE BY THIS AFTERNOON. ALONG AND SOUTHEAST OF A
FAIRBURY IL TO VALPARAISO IN LINE EXPECT STRATUS TO LINGER INTO
THE AFTERNOON...LONGEST FOR PORTIONS OF NORTHWEST INDIANA WHERE
TEMPERATURES WERE LOWERED A FEW DEGREES ACCORDINGLY.
OVERNIGHT AMDAR SOUNDINGS OUT OF CHICAGO SHOW SHARP TEMPERATURE
INVERSION BASED AROUND 950MB WITH TEMPS QUICKLY WARMING TO AROUND
+7C BETWEEN 925MB AND 850MB. SEASONAL CLIMO SUGGESTS THAT THESE
TEMPERATURES ALOFT WOULD SUPPORT AFTERNOON HIGHS FROM THE MID 40S
TO LOW 50S AND WHILE EARLY MORNING CLOUDS/FOG COULD SLOW THE
WARMING...SHOULD SEE TEMPERATURES JUMP ONCE THE SUN COMES OUT.
SEVERAL MODELS INCLUDING THE GFS AND NAM ARE WAY TOO COLD WITH
UNREALISTIC IMPACTS FROM MODEL SNOW DEPTH. SIMILARLY FOR
SATURDAY... WENT ON THE WARMER END OF THE SPECTRUM FOR
TEMPERATURES WITH THERMAL RIDGE PUSHING OVERHEAD AND SEVERAL
MODELS CONTINUING TO STRUGGLE WITH SURFACE TEMPS DUE TO SNOW.
FORECASTING AFTERNOON HIGHS IN THE UPPER 40S TO LOW 50S WITH A
LIGHT SOUTH BREEZE THROUGH THE DAY.
DEUBELBEISS
&&
.LONG TERM...
256 AM CST
SATURDAY NIGHT THROUGH THURSDAY...
SUNDAY THROUGH THURSDAY...
UPPER RIDGE THAT BRINGS UNSEASONABLE WARMTH TO THE AREA WILL
CONTINUE TO PROGRESS EAST INTO THE ATLANTIC SUNDAY WHILE UPPER LOW
IS PROGGED TO CUT OFF ACROSS THE MISSISSIPPI VALLEY. THERE ARE
TIMING DIFFERENCES BETWEEN THE MODEL SOLUTIONS WITH THE NAM AND
ECWMF LEADING THE GFS WITH FASTER SOLUTIONS BY 6-12HRS...AND THE
GFS REMAINS SLIGHTLY SLOWER THAN EVEN THE GEFS MEAN. UPPER LOW
WILL BRING WITH IT SOMEWHAT COOLER TEMPERATURES WITH H85 TEMPS
PROGGED TO FALL BACK BELOW 0C BRIEFLY SUNDAY WHICH WILL RESULT IN
SUNDAY TEMPERATURES ONLY MAXING OUT IN THE 40S...WHICH IS STILL
WELL ABOVE NORMAL. COULD BE SLIGHTLY WARMER SUNDAY IF THE SLOWER
GFS VERIFIES BUT OTHERWISE TIMING DIFFERENCES BETWEEN THE MODELS
SOMEWHAT MOOT AS OVERALL FORCING WITH THIS SYSTEM IS WEAK AND
MOISTURE IS MEAGER SO DONT ANTICIPATE MUCH IF ANYTHING AS FAR AS
QPF OR POPS. NAM CONTINUES TO SHOW MOISTENING LOW LEVELS WITH
DRIZZLE DEVELOPING BUT NOT READY TO BITE OFF ON THIS YET AS
SOUNDINGS LEADING UP TO THIS EVENT SHOW A FAIRLY DEEP LAYER OR DRY
AIR THAT MAY BE DIFFICULT TO OVERCOME.
UPPER LOW CONTINUES TO THE EAST COAST BY LATE MONDAY WITH A MODEST
UPPER RIDGE AND WARMER AIR OVERSPREADING THE LOCAL AREA BY LATE
MONDAY. THEN...UPPER PATTERN IS PROGGED TO BECOME MORE ZONAL FROM
TUESDAY ON WITH A SERIES OF SHORTWAVES DIGGING INTO THE MIDWEST
THE LATTER HALF OF THE WEEK. CONFIDENCE IN THE DETAILS DROPS
CONSIDERABLY WITH SIGNIFICANT TIMING AND TRACK DIFFERENCES IN THE
MODELS...WITH THE ECMWF IN PARTICULAR ADVERTISING A MORE ACTIVE
AND WET PATTERN FOR THE LOCAL AREA. ADDED SOME PERIODS OF SLIGHT
POPS PER GENERAL MODEL CONSENSUS BUT OTHERWISE DID NOT MAKE ANY
SIGNIFICANT CHANGES TO THE FORECAST FOR THE UPCOMING WEEK AND
EXPECT ABOVE NORMAL TEMPS TO CONTINUE.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* BRIEF PERIOD OF IFR CIG/VIS THIS MORNING.
RATZER/BEACHLER
//DISCUSSION...UPDATED 12Z...
SLOW MOVING BANK OF LOW STRATUS HAS SEEN REDEVELOPMENT ALONG THE
TRAILING EDGE OVERNIGHT...WITH LOWER CIGS 200-600 FT AND IFR/LIFR
VIS IN A FEW SPOTS WHERE CLOUD DECK HAD REDEVELOPED/BUILT DOWN TO
NEAR THE SURFACE. IR SATELLITE TRENDS CONTINUE TO SHOW EROSION
FROM THE WEST/NORTH/NORTHEAST ACROSS FAR NORTHEAST IL...THOUGH IT
APPEARS AREA BETWEEN ORD-DPA-ARR MAY BE THE LAST TO ERODE OVER THE
NEXT FEW HOURS. LOWEST CONDITIONS HAVE BEEN AND ARE EXPECTED TO
REMAIN IN THE ARR-DPA AREA...WITH IMPROVEMENT AREA-WIDE BY MID-
MORNING. RAP SHORT TERM GUIDANCE HANDLING TRENDS FAIRLY WELL...
LENDING SUPPORT TO SATELLITE TRENDS THIS MORNING. ONCE CLEARING
OCCURS...VFR CONDITIONS EXPECTED FOR REMAINDER OF THE FORECAST
PERIOD.
SOUTHWEST WINDS 10 KTS OR LESS EXPECTED THROUGH THE PERIOD...AS
SURFACE HIGH PRESSURE PROPAGATES THROUGH THE OHIO VALLEY. WIND
DIRECTION LIKELY TO BECOME A LITTLE MORE SOUTH ON SATURDAY AS THE
CENTER OF THE HIGH MOVES OFF TO THE EAST.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH IN CIG/VIS TRENDS THIS MORNING...THOUGH MEDIUM IN EXACT CIG
HGT/VIS.
RATZER/BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT THROUGH THURSDAY...VFR. WX NIL. WINDS WEST TO
SOUTH WITH WINDS GENERALLY AT OR UNDER 10KT.
RATZER
&&
.MARINE...
320 AM CST
HIGH PRESSURE WILL BE STRENGTHENING AND EXPANDING ACROSS THE OHIO
VALLEY TODAY WHILE A LOW PRESSURE TROUGH MOVES AWAY TO THE
NORTHEAST OF THE LAKES. WEST WINDS GUSTING 25-30 KTS EARLIER WILL
GRADUALLY DIMINISH AND BACK SOUTHWEST TODAY AS WEAKER RIDGING
DEVELOPS ACROSS THE WESTERN LAKES. ANOTHER LOW WILL LIFT ACROSS
CANADA AND HUDSON BAY TONIGHT AND SATURDAY...TIGHTENING THE
GRADIENT ACROSS LAKE MICHIGAN AND INCREASING WINDS AGAIN LATE
TODAY AND TONIGHT ESPECIALLY ACROSS THE NORTHERN PARTS OF THE
LAKE...WHERE WINDS WILL INCREASE TO NEAR 30 KT ON SATURDAY AND
SATURDAY NIGHT WITH A FEW MARGINAL GALE GUSTS POSSIBLE ESPECIALLY
SATURDAY EVENING. THE CANADIAN LOW WILL TRAIL A WEAK COLD FRONT
ACROSS THE LAKE ON SUNDAY...WITH A WEAKENING OF THE GRADIENT AND A
WIND SHIFT BRIEFLY BACK TO THE WEST AS WEAK HIGH PRESSURE RIDGE
BUILDS IN SUNDAY NIGHT. LONGER RANGE PATTERN FAVORS PERSISTENT
SOUTH-SOUTHWEST WINDS ACROSS THE LAKE EARLY NEXT WEEK...WITH
ANOTHER LOW MOVING FROM NEAR LAKE WINNIPEG TO HUDSON BAY MONDAY
AND TUESDAY.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
548 AM CST FRI DEC 4 2015
.SHORT TERM...
256 AM CST
THROUGH SATURDAY NIGHT...
EARLY THIS MORNING...HIGH PRESSURE IS CENTERED ACROSS THE LOWER
OHIO VALLEY WITH RIDGING EXTENDING ACROSS THE UPPER MIDWEST.
SATELLITE IMAGERY AND AREA OBSERVATIONS SHOWS LOW STRATUS ACROSS
MUCH OF NORTHEAST AND EAST CENTRAL ILLINOIS AND NORTHWEST INDIANA.
WHILE THE BACK EDGE HAS BEEN STEADILY ERODING FROM THE WEST ACROSS
PORTIONS OF FAR NORTHERN ILLINOIS OVERNIGHT...SOUTH OF I-80 THE
STRATUS HAS BEEN SPREADING NORTH...AND LOWERING WITH VISIBILITY
DROPPING BELOW A MILE IN SEVERAL LOCATIONS. GENERALLY LIKE
HRRR/RAP CIG/VSBY TRENDS PARTICULARLY SOUTH OF I-80 WHERE THE
GREATEST THREAT OF AT LEAST SOME PATCHY DENSE FOG APPEARS TO BE
THIS MORNING. WILL CONTINUE TO MONITOR TRENDS CLOSELY AS A DENSE
FOG ADVISORY MAY BE NEEDED FOR SOME AREAS. CLOUD COVER WILL BE
SLOW TO ERODE TODAY...THOUGH THE NORTHWEST HALF OR SO OF THE CWA
SHOULD SEE SUNSHINE BY THIS AFTERNOON. ALONG AND SOUTHEAST OF A
FAIRBURY IL TO VALPARAISO IN LINE EXPECT STRATUS TO LINGER INTO
THE AFTERNOON...LONGEST FOR PORTIONS OF NORTHWEST INDIANA WHERE
TEMPERATURES WERE LOWERED A FEW DEGREES ACCORDINGLY.
OVERNIGHT AMDAR SOUNDINGS OUT OF CHICAGO SHOW SHARP TEMPERATURE
INVERSION BASED AROUND 950MB WITH TEMPS QUICKLY WARMING TO AROUND
+7C BETWEEN 925MB AND 850MB. SEASONAL CLIMO SUGGESTS THAT THESE
TEMPERATURES ALOFT WOULD SUPPORT AFTERNOON HIGHS FROM THE MID 40S
TO LOW 50S AND WHILE EARLY MORNING CLOUDS/FOG COULD SLOW THE
WARMING...SHOULD SEE TEMPERATURES JUMP ONCE THE SUN COMES OUT.
SEVERAL MODELS INCLUDING THE GFS AND NAM ARE WAY TOO COLD WITH
UNREALISTIC IMPACTS FROM MODEL SNOW DEPTH. SIMILARLY FOR
SATURDAY... WENT ON THE WARMER END OF THE SPECTRUM FOR
TEMPERATURES WITH THERMAL RIDGE PUSHING OVERHEAD AND SEVERAL
MODELS CONTINUING TO STRUGGLE WITH SURFACE TEMPS DUE TO SNOW.
FORECASTING AFTERNOON HIGHS IN THE UPPER 40S TO LOW 50S WITH A
LIGHT SOUTH BREEZE THROUGH THE DAY.
DEUBELBEISS
&&
.LONG TERM...
256 AM CST
SATURDAY NIGHT THROUGH THURSDAY...
SUNDAY THROUGH THURSDAY...
UPPER RIDGE THAT BRINGS UNSEASONABLE WARMTH TO THE AREA WILL
CONTINUE TO PROGRESS EAST INTO THE ATLANTIC SUNDAY WHILE UPPER LOW
IS PROGGED TO CUT OFF ACROSS THE MISSISSIPPI VALLEY. THERE ARE
TIMING DIFFERENCES BETWEEN THE MODEL SOLUTIONS WITH THE NAM AND
ECWMF LEADING THE GFS WITH FASTER SOLUTIONS BY 6-12HRS...AND THE
GFS REMAINS SLIGHTLY SLOWER THAN EVEN THE GEFS MEAN. UPPER LOW
WILL BRING WITH IT SOMEWHAT COOLER TEMPERATURES WITH H85 TEMPS
PROGGED TO FALL BACK BELOW 0C BRIEFLY SUNDAY WHICH WILL RESULT IN
SUNDAY TEMPERATURES ONLY MAXING OUT IN THE 40S...WHICH IS STILL
WELL ABOVE NORMAL. COULD BE SLIGHTLY WARMER SUNDAY IF THE SLOWER
GFS VERIFIES BUT OTHERWISE TIMING DIFFERENCES BETWEEN THE MODELS
SOMEWHAT MOOT AS OVERALL FORCING WITH THIS SYSTEM IS WEAK AND
MOISTURE IS MEAGER SO DONT ANTICIPATE MUCH IF ANYTHING AS FAR AS
QPF OR POPS. NAM CONTINUES TO SHOW MOISTENING LOW LEVELS WITH
DRIZZLE DEVELOPING BUT NOT READY TO BITE OFF ON THIS YET AS
SOUNDINGS LEADING UP TO THIS EVENT SHOW A FAIRLY DEEP LAYER OR DRY
AIR THAT MAY BE DIFFICULT TO OVERCOME.
UPPER LOW CONTINUES TO THE EAST COAST BY LATE MONDAY WITH A MODEST
UPPER RIDGE AND WARMER AIR OVERSPREADING THE LOCAL AREA BY LATE
MONDAY. THEN...UPPER PATTERN IS PROGGED TO BECOME MORE ZONAL FROM
TUESDAY ON WITH A SERIES OF SHORTWAVES DIGGING INTO THE MIDWEST
THE LATTER HALF OF THE WEEK. CONFIDENCE IN THE DETAILS DROPS
CONSIDERABLY WITH SIGNIFICANT TIMING AND TRACK DIFFERENCES IN THE
MODELS...WITH THE ECMWF IN PARTICULAR ADVERTISING A MORE ACTIVE
AND WET PATTERN FOR THE LOCAL AREA. ADDED SOME PERIODS OF SLIGHT
POPS PER GENERAL MODEL CONSENSUS BUT OTHERWISE DID NOT MAKE ANY
SIGNIFICANT CHANGES TO THE FORECAST FOR THE UPCOMING WEEK AND
EXPECT ABOVE NORMAL TEMPS TO CONTINUE.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* BRIEF PERIOD OF IFR CIG/VIS THIS MORNING.
RATZER
//DISCUSSION...UPDATED 12Z...
SLOW MOVING BANK OF LOW STRATUS HAS SEEN REDEVELOPMENT ALONG THE
TRAILING EDGE OVERNIGHT...WITH LOWER CIGS 200-600 FT AND IFR/LIFR
VIS IN A FEW SPOTS WHERE CLOUD DECK HAD REDEVELOPED/BUILT DOWN TO
NEAR THE SURFACE. IR SATELLITE TRENDS CONTINUE TO SHOW EROSION
FROM THE WEST/NORTH/NORTHEAST ACROSS FAR NORTHEAST IL...THOUGH IT
APPEARS AREA BETWEEN ORD-DPA-ARR MAY BE THE LAST TO ERODE OVER THE
NEXT FEW HOURS. LOWEST CONDITIONS HAVE BEEN AND ARE EXPECTED TO
REMAIN IN THE ARR-DPA AREA...WITH IMPROVEMENT AREA-WIDE BY MID-
MORNING. RAP SHORT TERM GUIDANCE HANDLING TRENDS FAIRLY WELL...
LENDING SUPPORT TO SATELLITE TRENDS THIS MORNING. ONCE CLEARING
OCCURS...VFR CONDITIONS EXPECTED FOR REMAINDER OF THE FORECAST
PERIOD.
SOUTHWEST WINDS 10 KTS OR LESS EXPECTED THROUGH THE PERIOD...AS
SURFACE HIGH PRESSURE PROPAGATES THROUGH THE OHIO VALLEY. WIND
DIRECTION LIKELY TO BECOME A LITTLE MORE SOUTH ON SATURDAY AS THE
CENTER OF THE HIGH MOVES OFF TO THE EAST.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH IN CIG/VIS TRENDS THIS MORNING...THOUGH MEDIUM IN EXACT CIG
HGT/VIS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT THROUGH THURSDAY...VFR. WX NIL. WINDS WEST TO
SOUTH WITH WINDS GENERALLY AT OR UNDER 10KT.
RATZER
&&
.MARINE...
320 AM CST
HIGH PRESSURE WILL BE STRENGTHENING AND EXPANDING ACROSS THE OHIO
VALLEY TODAY WHILE A LOW PRESSURE TROUGH MOVES AWAY TO THE
NORTHEAST OF THE LAKES. WEST WINDS GUSTING 25-30 KTS EARLIER WILL
GRADUALLY DIMINISH AND BACK SOUTHWEST TODAY AS WEAKER RIDGING
DEVELOPS ACROSS THE WESTERN LAKES. ANOTHER LOW WILL LIFT ACROSS
CANADA AND HUDSON BAY TONIGHT AND SATURDAY...TIGHTENING THE
GRADIENT ACROSS LAKE MICHIGAN AND INCREASING WINDS AGAIN LATE
TODAY AND TONIGHT ESPECIALLY ACROSS THE NORTHERN PARTS OF THE
LAKE...WHERE WINDS WILL INCREASE TO NEAR 30 KT ON SATURDAY AND
SATURDAY NIGHT WITH A FEW MARGINAL GALE GUSTS POSSIBLE ESPECIALLY
SATURDAY EVENING. THE CANADIAN LOW WILL TRAIL A WEAK COLD FRONT
ACROSS THE LAKE ON SUNDAY...WITH A WEAKENING OF THE GRADIENT AND A
WIND SHIFT BRIEFLY BACK TO THE WEST AS WEAK HIGH PRESSURE RIDGE
BUILDS IN SUNDAY NIGHT. LONGER RANGE PATTERN FAVORS PERSISTENT
SOUTH-SOUTHWEST WINDS ACROSS THE LAKE EARLY NEXT WEEK...WITH
ANOTHER LOW MOVING FROM NEAR LAKE WINNIPEG TO HUDSON BAY MONDAY
AND TUESDAY.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
508 AM CST FRI DEC 4 2015
.SHORT TERM...(Today)
ISSUED AT 328 AM CST FRI DEC 4 2015
Persistent area of low clouds continues to blanket locations east of
the I-55 corridor early this morning. 09z/3am obs also show
widespread dense fog across this area, prompting the issuance of a
Dense Fog Advisory along/east of a Bloomington...to Decatur...to
Taylorville line. With high pressure centered over the Ohio River
Valley, very light S/SW low-level flow has been noted across the
northern half of the CWA: however, winds on the back side of the
high are beginning to take on a S/SE component across south-central
Illinois. IR satellite imagery is showing the low clouds/fog
inching westward just south of Taylorville, with the latest HRRR
suggesting this moisture might curl northward into the Springfield
and Lincoln areas in the next few hours. Will keep an eye on
satellite trends to see if this comes to pass and advisory needs to
be expanded westward to I-55. Due to the low sun angle and only
light low-level flow, fog will be slow to dissipate today. In fact,
HRRR suggests the far E/NE CWA near the Indiana border may remain
overcast for much of the day. Have extended the Dense Fog Advisory
until 17z/11am, but have kept skies mostly cloudy along and
northeast of a Champaign to Paris line until mid to late afternoon.
The evolution of the fog/clouds will have a big impact on high
temperatures. Based on expected trends, have kept readings coolest
in the lower 40s near Danville and Paris, with highs reaching the
upper 40s to around 50 elsewhere.
.LONG TERM...(Tonight through Thursday)
ISSUED AT 328 AM CST FRI DEC 4 2015
While the HRRR and Rapid Refresh have generally done a good job with
the low clouds/fog this morning, the NAM and especially the GFS have
not. In fact, GFS soundings indicate mostly clear skies and
unrestricted visbys today! As a result, am very skeptical about
forecast soundings from both models tonight. The GFS is again
clear: however, the NAM hints at low-level saturation and possible
fog. The high pressure center currently near Evansville, Indiana is
expected to shift into southern Ohio tonight, with the corresponding
ridge axis extending southwestward into the Ozarks. This will
result in the lightest winds across the E/SE CWA, with only a light
S/SW flow further north and west. Given persistent weather pattern,
have decided to include patchy fog mention along/southeast of a
Champaign to Taylorville line once again tonight. Once any morning
fog burns off, mostly sunny skies will prevail on Saturday. Thanks
to a good deal of sunshine and light southerly winds, afternoon high
temperatures will climb at least 10 degrees above normal for this
time of year into the lower 50s.
00z Dec 4 models are still having difficulty with the exact timing
and track of the next approaching short-wave early next week. The
ECMWF is about 6-12 hours faster with the wave than the GFS,
bringing it across central Illinois Sunday afternoon. Meanwhile,
the GFS is more amplified and slower, tracking the feature across
the area Sunday night into Monday. Run-to-run consistency remains
poor with both models, but will stick with the slightly more stable
GFS here. As synoptic lift increases ahead of the wave, clouds will
be on the increase on Sunday. The airmass will initially be quite
dry due to the presence of the strong surface ridge early in the
period, so moisture will remain limited. As a result, will only
feature a slight chance PoP for rain across the W/SW CWA Sunday
afternoon, then mainly across the S/SE Sunday night. These low
chance PoPs may need to be extended into Monday as well if the GFS
verifies. After that, models bring a series of ill-defined weak
short-waves across the CONUS through next week. Pinning down the
exact timing of these features within the zonal flow pattern will be
difficult. Given this fact and the overall lack of deep-layer
moisture, will continue with a mild and dry forecast through the
remainder of the extended.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 505 AM CST FRI DEC 4 2015
Variable conditions exist across the TAF forecast area with VLIFR
conditions prevailing just east of I-55, while MVFR and IFR
conditions are being reported west of the interstate. This will
continue through about 17z before we see a significant improvement
with confidence low for DEC and CMI where sounding data suggests
it may not be until 19z before vsbys and cigs improve. Even if we
do see cigs and vsbys come up across the east this afternoon, it
appears the setup will be about the same tonight as the surface
high and light wind fields prevail across the forecast area. Look
for light southerly winds today with speeds of 10 kts or less. The
winds will gradually back into a light southeast flow tonight.
&&
.ILX Watches/Warnings/Advisories...
Dense Fog Advisory until 11 AM CST this morning for ILZ038-
043>046-052>057-061>063-066>068-071>073.
&&
$$
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Smith
Area Forecast Discussion
National Weather Service Louisville KY
1057 AM EST FRI DEC 4 2015
...Forecast Update...
Issued at 1055 AM Fri Dec 4 2015
Fog is finally dissipating in a lot of the valleys, but the more
extensive area of fog/stratus over Indiana is going nowhere fast.
Have updated products to remove the fog mention, except over our
northernmost counties in southern Indiana, where the clouds/fog will
hang on for much of the afternoon. Temps are just warm enough that
in daylight conditions, freezing fog should not be as much of an
issue as it had been earlier. Therefore will just keep it plain old
fog. Have clipped max temps by several degrees where the clouds and
fog remain, but if it`s persistent enough, even the mid 40s in the
revised forecast may be too generous. Still on track for around 50
elsewhere.
Issued at 925 AM Fri Dec 4 2015
Patchy freezing fog is mostly dissipating based on latest METARs and
area webcams. Still seeing some of the deeper river valleys pretty
well socked in, so will take a bit slower approach to removing the
early fog wording from the ZFP. A more extensive area of fog/stratus
sits over Indiana just north of our CWA boundary, and I have little
confidence that it will go anywhere given poor mixing under a 1037mb
high pressure, and low December sun angle. That said, the current
forecast should be pretty well on track, so will just refresh to
pull the fog wording as the valleys finally start to mix a bit, and
will keep an eye on whether the stratus deck tries to creep into our
Indiana counties.
.SHORT TERM (Now through Saturday)...
Issued at 300 AM EST Fri Dec 4 2015
In the near term, high pressure will drift overhead early this
morning and then move slowly eastward during the day today. IR
satellite imagery reveals clear skies across the region. A decent
ridge/valley decoupling has taken place with the cooler valleys
presently sitting in the mid 20s with upper 20s to around 30
elsewhere. Dry air is abundant aloft across the region. However,
we do have some low-level moisture down near the surface which may
result in some areas of freezing fog this morning. The best chances
for the fog look to be across our southern Indiana counties and in
the KY river valley region of central KY. Temperatures may cool a
few more degrees before sunrise with most locations seeing readings
in the low-mid 20s in the valleys and in the mid-upper 20s elsewhere.
For Today through Saturday, quiet weather is expected as high
pressure will continue to dominance our weather pattern. Highs this
afternoon will warm into the upper 40s to around 50 in the north
with lower 50s likely across southern KY. Another cool night looks
likely tonight with lows in the valleys cooling into the lower-mid
20s with mid-upper 20s elsewhere. We will pick up a bit more
southerly flow on Saturday with mostly sunny skies. Temperatures
look to warm into the lower 50s in the north with low-mid 50s across
the south.
.LONG TERM (Saturday Night through Thursday)...
Issued at 323 AM EST Fri Dec 4 2015
In the long term period, a progressive flow will remain in place
aloft with a series of compact upper level lows rolling from east to
west across the CONUS. The first of these will transverse our
region late Sunday and into the day on Monday. Moisture is not all
that plentiful with the system as return flow from the Gulf will not
have sufficient time to moisten up the column. However, model time-
height cross sections do suggest plenty of mid-high level cloud
cover to push through with this system. Ascent is not overly
strong, but forcing with the upper low (mainly due to steep lapse
rates) look to be enough to continue low chance PoPs in the Sunday
night/Monday time frame.
The upper flow will then flatten back out by Tuesday, only to re-
amplify as the next upper level low crosses the region Wednesday
night into Thursday as it ejects from the northern Plains. Again,
large scale ascent with this system is not overly impressive, but
enough moisture and lift look available to warrant low chance PoPs
in the Wed night/Thursday time frame...despite the blended guidance
being a little more optimistic on dry conditions.
Temperatures through the period look to run a little above seasonal
normals. Typical early December highs average in the upper 40s. The
latest guidance suggests daily highs in the lower to middle 50s with
overnight lows in the mid-upper 30s. The warmest day looks to be
Thursday where some upper 50s across the south will be possible.
Overall, not much in the way of change from the previous forecast.
Looking further out, a more active weather pattern looks to take
shape as we head into late next week and into the mid part of
December. Latest teleconnection pattern suggest a
+AO/+NAO/+PNA/+EPO pattern in place by late next week. These
indices would support the series of rolling upper level lows across
the CONUS. However, as we head down the road, the models suggest a
downward trend in all the indices as we head toward mid-month. As
this downward trend occurs, we`re likely to see an active weather
pattern set up across the central US and eventually into the Ohio
Valley.
Initially, we`ll be on the warm side of the pattern with the threat
of additional heavy rainfall and milder than normal temperatures. As
the indices slide toward the neutral/negative range, we`ll
gradually see the sensible weather catch up with a more seasonal
cold pattern emerging after mid-month. It should be noted that the
long term models have struggled with timing of the downtrend in the
teleconnection indices. Past verification shows that they tend to
drop the indices too quick...so it would not be surprising to see
the eventual return to seasonal cold to be delayed slightly in later
forecasts.
&&
.AVIATION (12Z TAF Update)...
Updated at 610 AM EST Fri Dec 4 2015
Patchy fog/mist this morning at SDF/LEX/BWG will burn off between 13-
14z. Latest satellite imagery shows a LIFR stratus deck over east-
central IL and central IN, trying to expand southward. HRRR is
capturing this somewhat, best of the hi-res models, and takes it
southward to near the Ohio River in a few hours. It then should
either scatter out due to daytime mixing or retreat back to the
north. Given this though, still think SDF will remain clear but will
have to watch trends closely as models sometime poorly handle
shallow moisture within an inversion.
Otherwise, expect light/variable winds through the period. Another
clear/calm night will promote light fog formation at all sites,
starting after 06z.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........RAS
Short Term.....MJ
Long Term......MJ
Aviation.......ZBT
AREA FORECAST DISCUSSION
NWS JACKSON KY
958 AM EST FRI DEC 4 2015
.UPDATE...
ISSUED AT 958 AM EST FRI DEC 4 2015
VIS SAT CONTINUES TO SHOW RIVER VALLEY FOG...WHICH GIVEN THE TEMPS
THIS MORNING WILL LIKELY BE FREEZING FOG. NO ISSUES ROAD WISE ARE
EXPECTED THIS MORNING. THIS VALLEY FOG WILL CONTINUE TO DISSIPATE
THROUGH THE MORNING HOURS. UPDATED GRIDS TO REFLECT VALLEY FOG
LOCATIONS...OTHERWISE NOT MAJOR CHANGES NEEDED THIS UPDATE. DID
OPT TO UPDATE THE TEMP...DEWS... AND WINDS WITH LATEST OBS AND
TRENDS. GRIDS HAVE BEEN SENT TO NDFD.
UPDATE ISSUED AT 727 AM EST FRI DEC 4 2015
SINCE ALL TEMPERATURES ACROSS THE REGION ARE BELOW FREEZING...IT
IS LIKELY THAT WHATEVER PATCHY FOG HAS DEVELOPED ACROSS THE REGION
IS OF THE FREEZING VARIETY. AS SUCH...CHANGED WEATHER GRIDS FOR
THE NEXT COUPLE HOURS TO REFLECT PATCHY FREEZING FOG INSTEAD.
ALSO HIGHLIGHTED POTENTIAL IMPACTS IN THE HWO. HOWEVER...GIVEN THE
PATCHY NATURE OF THE FOG AND WITH LITTLE TO NO IMPACTS REPORTED
THUS FAR...DID NOT ISSUE ANY FURTHER PRODUCTS. MOST REPORTS THIS
MORNING HAVE BEEN FOR FROST RATHER THAN FOG. REGARDLESS...ANY
REMAINING FOG SHOULD BURN OFF OVER THE NEXT HOUR OR TWO AS WE
CONTINUE TO WARM UP. LOADED IN THE LATEST OBSERVATIONS TO MAKE
SURE THE NEAR TERM FORECAST WAS WELL ON TRACK WITH THE CURRENT
CONDITIONS. A NEW FORECAST PACKAGE WAS SENT OUT TO REFLECT THE
CHANGES IN FOG WORDING. ALL GRIDS WERE PUBLISHED AND SENT TO
NDFD/WEB.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 242 AM EST FRI DEC 4 2015
HIGH PRESSURE IS CURRENTLY DIRECTLY OVERHEAD THE STATE OF KENTUCKY
AS OF 7Z. THIS IS PROVIDING LIGHT WINDS AND STRONG SUBSIDENCE DURING
THE OVERNIGHT HOURS. WENT AHEAD AND LOWERED SOME OF THE DEEPER
VALLEY LOCATIONS LOW TEMPERATURES FOR EARLY THIS MORNING GIVEN THE
CURRENT OBSERVATIONS.
OTHERWISE...EXPECT QUIET AND CLEAR CONDITIONS THROUGH THE DURATION
OF THE SHORT TERM PERIOD AS THE HIGH PRESSURE REMAINS OVERHEAD.
AFTERNOON TEMPERATURES WILL CONTINUE TO SHOW AN INCREASING
TREND...WITH HIGHS TODAY TOPPING OUT AROUND THE 50 DEGREE
MARK...THEN CLIMBING TO THE MID TO UPPER 50S BY TOMORROW. STRONG
SUBSIDENCE AND MAXIMUM RADIATIONAL COOLING OVERNIGHT TONIGHT WILL
PROMOTE ANOTHER RIDGE VALLEY SPLIT AND SIGNIFICANT DIURNAL
DROPS...WITH UPPER 20S TO AROUND 30 EXPECTED ON THE RIDGES FOR
LOWS...AND LOW TO MID 20S IN THE VALLEYS.
THE ONE CONCERN DURING THIS FORECAST PERIOD WILL BE THE AMOUNT OF
DRY AIR BEING USHERED INTO THE REGION UNDER THE INFLUENCE OF THIS
HIGH PRESSURE SYSTEM. THIS WILL CREATE LOW DEW POINTS AND LOW RH
SITUATIONS BOTH THIS AFTERNOON...AND EVEN MORE SO SATURDAY
AFTERNOON. LUCKILY...WINDS WILL BE LIGHT AND PREVIOUS DAYS RAINS
WILL HELP TO MITIGATE SOME OF THE FIRE CONCERNS...BUT THIS WILL
CONTINUE TO BE SOMETHING TO MONITOR THROUGH THE UPCOMING WEEKEND.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 458 AM EST FRI DEC 4 2015
THE EXTENDED PERIOD WILL START OUT DRY AND PLEASANT...WITH ABOVE
NORMAL TEMPERATURES EXPECTED DURING THE DAY ON SUNDAY.
HOWEVER...CONDITIONS WILL START OUT QUITE COLD ACROSS THE AREA ON
SUNDAY MORNING...WITH LOWS DROPPING INTO THE LOW TO MID 20S IN OUR
VALLEYS...WHILE THE SURROUNDING RIDGES ONLY FALL INTO THE LOW TO
MID 30S. THE WEATHER IS EXPECTED TO REMAIN DRY THROUGH EARLY
MONDAY EVENING. AFTER MONDAY EVENING...HOWEVER...THE MODEL DATA
BEGINS TO DIVERGE...LEAVING US WITH AN UNCERTAIN FORECAST FROM
MONDAY NIGHT ONWARD. FOR NOW...WITH THE MODELS SHOWING A SERIES OF
FAST MOVING SHORT WAVES EJECTING OUT OF THE PLAINS AND ACROSS THE
EASTERN THIRD OF THE CONUS...DECIDED TO GO WITH LOW PRECIPITATION
CHANCES SUNDAY NIGHT THROUGH LATE MONDAY NIGHT. AFTER ANOTHER
POSSIBLE DRY PERIOD TUESDAY AND TUESDAY NIGHT...INTRODUCED MORE
RAIN CHANCES WEDNESDAY THROUGH THURSDAY...AS THE ECMWF MODEL TRIES
TO BRING A FAIRLY WELL DEVELOPED AREA OF LOW PRESSURE OUT OF THE
PLAINS AND ACROSS THE UPPER MISSISSIPPI VALLEY AND GREAT LAKES
REGIONS. THE SURFACE FRONT THAT WOULD BE ASSOCIATED WITH THIS
UPPER LOW WOULD WHAT WOULD BRING RAINFALL TO OUR AREA.
HOWEVER...THE GFS MODEL IS DRY FOR THURSDAY...WHEN THE ECMWF HAS
AN AREA OF RAINFALL AFFECTING THE AREA. WITH THAT IN MIND...WENT
WITH ONLY A SLIGHT CHANCE OF RAIN ACROSS EASTERN KENTUCKY FOR THE
WEDNESDAY THURSDAY TIME FRAME.
TEMPERATURES ACROSS THE AREA ARE EXPECTED TO BE GENERALLY ABOVE
NORMAL THROUGH OUT THE PERIOD...WITH DAY TIME HIGHS IN THE MID TO
UPPER 50S AND OVERNIGHT LOWS IN THE MID TO UPPER 30S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 656 AM EST FRI DEC 4 2015
A FEW INSTANCES OF PATCHY FOG HAVE BEEN REPORTED AT KSME AND KSYM
THIS MORNING...AND GIVEN THAT TEMPERATURES ARE BELOW FREEZING AT
THESE LOCATIONS...THIS IS LIKELY A FREEZING FOG SET UP. IMPACTS
SHOULD BE MINIMAL HOWEVER...AND FOG TO BURN OFF OVER THE NEXT 1
TO 2 HOURS AS WE START WARMING. OTHERWISE...HIGH PRESSURE WILL
REMAIN IN CONTROL OF THE REGION THROUGHOUT THE TAF PERIOD...
RESULTING IN LIGHT WINDS AND VFR/CLEAR CONDITIONS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...JMW
LONG TERM...AR
AVIATION...JMW
Area Forecast Discussion
National Weather Service Louisville KY
928 AM EST FRI DEC 4 2015
...Forecast Update...
Issued at 925 AM Fri Dec 4 2015
Patchy freezing fog is mostly dissipating based on latest METARs and
area webcams. Still seeing some of the deeper river valleys pretty
well socked in, so will take a bit slower approach to removing the
early fog wording from the ZFP. A more extensive area of fog/stratus
sits over Indiana just north of our CWA boundary, and I have little
confidence that it will go anywhere given poor mixing under a 1037mb
high pressure, and low December sun angle. That said, the current
forecast should be pretty well on track, so will just refresh to
pull the fog wording as the valleys finally start to mix a bit, and
will keep an eye on whether the stratus deck tries to creep into our
Indiana counties.
.SHORT TERM (Now through Saturday)...
Issued at 300 AM EST Fri Dec 4 2015
In the near term, high pressure will drift overhead early this
morning and then move slowly eastward during the day today. IR
satellite imagery reveals clear skies across the region. A decent
ridge/valley decoupling has taken place with the cooler valleys
presently sitting in the mid 20s with upper 20s to around 30
elsewhere. Dry air is abundant aloft across the region. However,
we do have some low-level moisture down near the surface which may
result in some areas of freezing fog this morning. The best chances
for the fog look to be across our southern Indiana counties and in
the KY river valley region of central KY. Temperatures may cool a
few more degrees before sunrise with most locations seeing readings
in the low-mid 20s in the valleys and in the mid-upper 20s elsewhere.
For Today through Saturday, quiet weather is expected as high
pressure will continue to dominance our weather pattern. Highs this
afternoon will warm into the upper 40s to around 50 in the north
with lower 50s likely across southern KY. Another cool night looks
likely tonight with lows in the valleys cooling into the lower-mid
20s with mid-upper 20s elsewhere. We will pick up a bit more
southerly flow on Saturday with mostly sunny skies. Temperatures
look to warm into the lower 50s in the north with low-mid 50s across
the south.
.LONG TERM (Saturday Night through Thursday)...
Issued at 323 AM EST Fri Dec 4 2015
In the long term period, a progressive flow will remain in place
aloft with a series of compact upper level lows rolling from east to
west across the CONUS. The first of these will transverse our
region late Sunday and into the day on Monday. Moisture is not all
that plentiful with the system as return flow from the Gulf will not
have sufficient time to moisten up the column. However, model time-
height cross sections do suggest plenty of mid-high level cloud
cover to push through with this system. Ascent is not overly
strong, but forcing with the upper low (mainly due to steep lapse
rates) look to be enough to continue low chance PoPs in the Sunday
night/Monday time frame.
The upper flow will then flatten back out by Tuesday, only to re-
amplify as the next upper level low crosses the region Wednesday
night into Thursday as it ejects from the northern Plains. Again,
large scale ascent with this system is not overly impressive, but
enough moisture and lift look available to warrant low chance PoPs
in the Wed night/Thursday time frame...despite the blended guidance
being a little more optimistic on dry conditions.
Temperatures through the period look to run a little above seasonal
normals. Typical early December highs average in the upper 40s. The
latest guidance suggests daily highs in the lower to middle 50s with
overnight lows in the mid-upper 30s. The warmest day looks to be
Thursday where some upper 50s across the south will be possible.
Overall, not much in the way of change from the previous forecast.
Looking further out, a more active weather pattern looks to take
shape as we head into late next week and into the mid part of
December. Latest teleconnection pattern suggest a
+AO/+NAO/+PNA/+EPO pattern in place by late next week. These
indices would support the series of rolling upper level lows across
the CONUS. However, as we head down the road, the models suggest a
downward trend in all the indices as we head toward mid-month. As
this downward trend occurs, we`re likely to see an active weather
pattern set up across the central US and eventually into the Ohio
Valley.
Initially, we`ll be on the warm side of the pattern with the threat
of additional heavy rainfall and milder than normal temperatures. As
the indices slide toward the neutral/negative range, we`ll
gradually see the sensible weather catch up with a more seasonal
cold pattern emerging after mid-month. It should be noted that the
long term models have struggled with timing of the downtrend in the
teleconnection indices. Past verification shows that they tend to
drop the indices too quick...so it would not be surprising to see
the eventual return to seasonal cold to be delayed slightly in later
forecasts.
&&
.AVIATION (12Z TAF Update)...
Updated at 610 AM EST Fri Dec 4 2015
Patchy fog/mist this morning at SDF/LEX/BWG will burn off between 13-
14z. Latest satellite imagery shows a LIFR stratus deck over east-
central IL and central IN, trying to expand southward. HRRR is
capturing this somewhat, best of the hi-res models, and takes it
southward to near the Ohio River in a few hours. It then should
either scatter out due to daytime mixing or retreat back to the
north. Given this though, still think SDF will remain clear but will
have to watch trends closely as models sometime poorly handle
shallow moisture within an inversion.
Otherwise, expect light/variable winds through the period. Another
clear/calm night will promote light fog formation at all sites,
starting after 06z.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........RAS
Short Term.....MJ
Long Term......MJ
Aviation.......ZBT
AREA FORECAST DISCUSSION
National Weather Service Paducah KY
526 AM CST FRI DEC 4 2015
.UPDATE...
Issued at 526 AM CST FRI DEC 4 2015
The AVIATION section has been updated for the 12Z TAF issuance.
&&
.SHORT TERM...(Today through Sunday)
Issued at 248 AM CST FRI DEC 4 2015
Previous forecast update issued at 213 am CST Friday Dec 4 2015
discussed the Dense Fog Advisory/black ice potential, so will not
cover again here. However, did add a special weather statement for
the remainder of the WFO PAH forecast area until 8 am CST to
handle isolated fog/black ice potential outside the advisory
area.
With the center of high pressure expected to move east of the area
later today, a general easterly flow should persist across the
region through at least 15z (9 am CST) Saturday, before becoming
broadly southeasterly and South for the remainder of the short
term forecast period. Strong insolation (outside of the fog areas)
and shallow mixing should bring temperatures back into the 50s
today.
The 00z deterministic runs of the 20 km GFS, SREF, and 12km NAM-
WRF seem to have a good handle on the the closed low off Vancouver
Island this morning, with the advancing north to south shortwave
along the western U.S. coastline. For the short term time period,
mainly Sunday, this shortwave may provide sufficient lift to
generate some patchy sprinkles or drizzle across the area. Most
areas will likely remain dry, but added a mention in the gridded
forecast to handle the low probability occurrence of trace
precipitation. Main rain chances for the period are addressed in
the long term forecast discussion.
.LONG TERM...(Sunday Night through Friday)
Issued at 248 AM CST FRI DEC 4 2015
Overall forecast confidence is moderate at this time. The details of
small-scale upper-level disturbances moving east through/near the
region will clutter the PoP forecast, as the models are struggling
to handle them consistently. However, the overwhelming signal is for
near normal temperatures at the beginning of the period to warm up
some 5 to 10 degrees above normal through the work week.
The models continue to bring an upper-level storm system eastward
through the region Sunday night and Monday. The 00Z ECMWF is most
consistent with the consensus from last night`s models. It spits out
scant QPF late Sunday into Sunday night. The 00Z is a bit wetter and
slower emphasizing Sunday night into Monday. Will keep slight
chances of what should be very light rain or drizzle mainly behind
the cold front Sunday night and Monday.
The medium-range models have an energetic zonal flow crashing into
the Pacific Northwest for much of the week. Individual disturbances
in the flow amplify into closed lows as they emerge out of the
Rockies. The question is how far south does this amplification
occur? The farther south the development the slower the progression
eastward. This causes fairly wide differences in timing features
through/near our region, which causes considerable uncertainty in
the PoPs generally from Tuesday night through the remainder of the
work week.
Would prefer to keep the forecast dry beyond Monday and wait for
more clarity in the models before introducing PoPs, but border
constraints make that impossible at this time. Dried it out when and
where I could, but there remain a few areas of low chance PoPs from
Wednesday through Friday.
The overall flow pattern diverges considerably between the GFS and
ECMWF by next week, so confidence declines heading into Thursday and
especially Friday. However, there is no sign of cold air to impact
the region, so the relatively mild conditions will continue.
&&
.AVIATION...
Issued at 526 AM CST FRI DEC 4 2015
Very dry surface high pressure will dominate the region throughout
the 12Z TAF period, so the only potential problem for aviation
will be late night/early morning fog formation. Lots of MVFR to
IFR visibilities across the area this morning, but the large area
of dense fog has stayed north of the TAF sites so far and it is
not expected to bodily move over any of them this morning. A light
northeast wind will mix down this afternoon, but they will likely
go calm again tonight. Guidance is choking on the dry air and is
not developing any fog tonight. Persistence tells a different
story, but we will assume that more mixing this afternoon will
keep the fog in check tonight.
&&
.PAH Watches/Warnings/Advisories...
IL...Dense Fog Advisory until 11 AM CST this morning for ILZ075>078-
080>090-092-093.
MO...Dense Fog Advisory until 11 AM CST this morning for MOZ076-086-
087-100-107>111-114.
IN...Dense Fog Advisory until 11 AM CST this morning for INZ081-082-
085>087.
KY...Dense Fog Advisory until 11 AM CST this morning for KYZ018.
&&
$$
UPDATE...DRS
SHORT TERM...Smith
LONG TERM...Smith
AVIATION...DRS
Area Forecast Discussion
National Weather Service Louisville KY
608 AM EST FRI DEC 4 2015
...Updated Aviation Discussion...
.SHORT TERM (Now through Saturday)...
Issued at 300 AM EST Fri Dec 4 2015
In the near term, high pressure will drift overhead early this
morning and then move slowly eastward during the day today. IR
satellite imagery reveals clear skies across the region. A decent
ridge/valley decoupling has taken place with the cooler valleys
presently sitting in the mid 20s with upper 20s to around 30
elsewhere. Dry air is abundant aloft across the region. However,
we do have some low-level moisture down near the surface which may
result in some areas of freezing fog this morning. The best chances
for the fog look to be across our southern Indiana counties and in
the KY river valley region of central KY. Temperatures may cool a
few more degrees before sunrise with most locations seeing readings
in the low-mid 20s in the valleys and in the mid-upper 20s elsewhere.
For Today through Saturday, quiet weather is expected as high
pressure will continue to dominance our weather pattern. Highs this
afternoon will warm into the upper 40s to around 50 in the north
with lower 50s likely across southern KY. Another cool night looks
likely tonight with lows in the valleys cooling into the lower-mid
20s with mid-upper 20s elsewhere. We will pick up a bit more
southerly flow on Saturday with mostly sunny skies. Temperatures
look to warm into the lower 50s in the north with low-mid 50s across
the south.
.LONG TERM (Saturday Night through Thursday)...
Issued at 323 AM EST Fri Dec 4 2015
In the long term period, a progressive flow will remain in place
aloft with a series of compact upper level lows rolling from east to
west across the CONUS. The first of these will transverse our
region late Sunday and into the day on Monday. Moisture is not all
that plentiful with the system as return flow from the Gulf will not
have sufficient time to moisten up the column. However, model time-
height cross sections do suggest plenty of mid-high level cloud
cover to push through with this system. Ascent is not overly
strong, but forcing with the upper low (mainly due to steep lapse
rates) look to be enough to continue low chance PoPs in the Sunday
night/Monday time frame.
The upper flow will then flatten back out by Tuesday, only to re-
amplify as the next upper level low crosses the region Wednesday
night into Thursday as it ejects from the northern Plains. Again,
large scale ascent with this system is not overly impressive, but
enough moisture and lift look available to warrant low chance PoPs
in the Wed night/Thursday time frame...despite the blended guidance
being a little more optimistic on dry conditions.
Temperatures through the period look to run a little above seasonal
normals. Typical early December highs average in the upper 40s. The
latest guidance suggests daily highs in the lower to middle 50s with
overnight lows in the mid-upper 30s. The warmest day looks to be
Thursday where some upper 50s across the south will be possible.
Overall, not much in the way of change from the previous forecast.
Looking further out, a more active weather pattern looks to take
shape as we head into late next week and into the mid part of
December. Latest teleconnection pattern suggest a
+AO/+NAO/+PNA/+EPO pattern in place by late next week. These
indices would support the series of rolling upper level lows across
the CONUS. However, as we head down the road, the models suggest a
downward trend in all the indices as we head toward mid-month. As
this downward trend occurs, we`re likely to see an active weather
pattern set up across the central US and eventually into the Ohio
Valley.
Initially, we`ll be on the warm side of the pattern with the threat
of additional heavy rainfall and milder than normal temperatures. As
the indices slide toward the neutral/negative range, we`ll
gradually see the sensible weather catch up with a more seasonal
cold pattern emerging after mid-month. It should be noted that the
long term models have struggled with timing of the downtrend in the
teleconnection indices. Past verification shows that they tend to
drop the indices too quick...so it would not be surprising to see
the eventual return to seasonal cold to be delayed slightly in later
forecasts.
&&
.AVIATION (12Z TAF Update)...
Updated at 610 AM EST Fri Dec 4 2015
Patchy fog/mist this morning at SDF/LEX/BWG will burn off between 13-
14z. Latest satellite imagery shows a LIFR stratus deck over east-
central IL and central IN, trying to expand southward. HRRR is
capturing this somewhat, best of the hi-res models, and takes it
southward to near the Ohio River in a few hours. It then should
either scatter out due to daytime mixing or retreat back to the
north. Given this though, still think SDF will remain clear but will
have to watch trends closely as models sometime poorly handle
shallow moisture within an inversion.
Otherwise, expect light/variable winds through the period. Another
clear/calm night will promote light fog formation at all sites,
starting after 06z.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Short Term........MJ
Long Term.........MJ
Aviation..........ZT
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
914 AM EST FRI DEC 4 2015
.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY WEATHER AND SLOWLY MODERATING
TEMPERATURES THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
MADE A NEAR TERM UPDATE TO SLIGHTLY ADJUST CLOUD COVER THROUGH THE
DAY BASED ON THE LATEST HI RES MODELS THAT SEEMED TO KEY ON THE
STRATUS OVER OHIO. WHILE THE HRRR SLIDES IT JUST INTO OUR
WESTERN-MOST ZONES...THAT APPEARS THAT WILL BE AS FAR AS IT GETS
BEFORE LOW LEVEL MIXING RESUMES AND SCATTERS OUT WHAT`S LEFT OF
THE CLOUD DECK OVER THE REGION.
TEMPERATURES WILL REMAIN RATHER STAGNANT UNTIL THE STRATUS
CLEARS. AFTER THAT TIME...SUFFICIENT INSOLATION SHOULD SUPPORT
HIGH TEMPERATURES JUST A TOUCH ABOVE NORMAL BY AFTERNOON.
CLEAR SKIES WILL CONTINUE INTO TONIGHT. DEWPOINTS WILL REMAIN LOW
AND SURFACE HIGH PRESSURE WILL MEANDER NEARBY. THIS SHOULD ALLOW
FOR FAIRLY EFFICIENT RADIATIONAL COOLING WITH WIDESPREAD LOWS IN
THE 20S.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
CLEAR AND DRY CONDITIONS WILL PERSIST THROUGH THE WEEKEND AS HIGH
PRESSURE SETTLES OVER THE REGION. UNDER ABUNDANT SUNSHINE...HIGH TEMPERATURES
WILL WARM THROUGH THE WEEKEND AS AXIS OF THE UPPER RIDGE SLOWLY
SHIFTS EAST AND CALM WINDS STIR FROM THE SOUTH. NIGHTTIME LOWS
WILL REMAIN NEAR OR JUST BELOW FREEZING AS THE CLEAR CONDITIONS
WILL LEAD TO RADIATIONAL COOLING AND DE-COUPLING OF THE LOWER
ATMOSPHERE. TAX
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
WEAK AND RELATIVELY DRY LOW PRESSURE SYSTEM WILL MOVE THROUGH THE
PLAINS APPROACHING OUR REGION TOWARD THE LATTER PART OF THE
WEEKEND. WITH THE LOW FULLY DETACHING FROM THE UPPER-LEVEL STREAM
TO THE NORTH...THE TRACK CONTINUES TO TREND SOUTH OF THE FORECAST
AREA. LATEST MODEL GUIDANCE VERY QUICKLY TRANSLATES THE WAVE TO
THE COAST...PULLING THE MEAGER MOISTURE AWAY FROM THE FORECAST
AREA. POPS HAVE BEEN REDUCED MONDAY NIGHT INTO TUESDAY.
CONFIDENCE IN THE EXTENDED FORECAST BEGINS TO WANE THEREAFTER AS
LONG RANGE MODELS ARE HAVING A TOUGH TIME WITH TIMING AND
STRENGTH OF A MID-WEEK WAVE. THERE IS AT LEAST SOME AGREEMENT ON
THE DEEPENING OF A BROAD TROUGH OVER THE WESTERN CONUS IN THE
LATTER PART OF NEXT WEEK. THIS WILL KEEP TEMPERATURES ABOVE
SEASONAL AVERAGES.
TAX
LITTLE CHANGE TO THE EXTENDED FROM THE PREVIOUS FORECAST. HIGH
PRESSURE WILL KEEP DRY AND MILD CONDITIONS THROUGH MONDAY. BLEND
OF MODELS CONSISTENT IN MOVING A WEAK LOW SOUTH OF THE FORECAST
AREA MONDAY TRANSITIONING TO A COASTAL LOW TUESDAY. LIMITED
MOISTURE AVAILABILITY AND TRACK OF THE LOW WILL KEEP DEEP MOISTURE
WELL SOUTH AND EAST. WILL GO WITH MODEL TRENDS AND KEEP ONLY
SLIGHT CHANCE POPS FAR SOUTHEAST RIDGES TUESDAY. HIGH PRESSURE
THEN BRINGS MORE DRY AND MILD CONDITIONS INTO LATE WEEK.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
STRATUS HAS ALREADY CLEARED FROM KZZV...AND WILL LIKEWISE
PROGRESSIVELY DO SO AT ALL SITES EAST OF THERE THROUGH THE NEXT
FEW HOURS. STRATUS CLEARING WILL BECOME MORE RAPID AFTER SUNRISE.
ALL SITES WILL BE CLEAR BY AFTERNOON WITH VFR CONDITIONS. FRIES
.OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY/...
VFR CONDITIONS THROUGH THE PERIOD.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1035 AM EST FRI DEC 4 2015
.UPDATE...
ISSUED AN UPDATE EARLIER TO WORK MORE CLOUD WORDING INTO THE
AFTERNOON HOURS. TIME OF YEAR AND LOW SOLAR ANGLE SUPPORTS THIS.
HOWEVER...LATEST SATELLITE TREND HAS BEEN SHOWING A THINNING AND
A GREATER TRANSPARENCY OF CLOUDS. EXPECT A VARIABLE SKY COVERAGE
BY NOON...BUT EXTREMELY SHALLOW LAYER OF SATURATION WILL MAKE IT
DIFFICULT TO NAIL DOWN THE CORRECT SKY COVER IN TEXT.
&&
.AVIATION...ISSUED 445 AM EST FRI DEC 4 2015
TIMING THE EXIT OF THE LOW CLOUDS WILL REMAIN THE MOST CHALLENGING
ASPECT OF THE TAFS. A LOWERING INVERSION HAS LED TO AN EXTENSIVE
AREA OF IFR CEILINGS ACROSS NRN INDIANA AND FAR SW LOWER MI...ON THE
DOORSTEP OF METRO DETROIT AS OF 0930Z. THE INFLUENCE OF THE WEST-
SOUTHWEST FLOW ACROSS LAKE MI MAY HOLD THE INVERSION BASE UP A
LITTLE HIGHER...THUS KEEPING CIGS ON THE LOW END OF THE MVFR RANGE.
WARMER AND DRIER LOW LEVEL AIR WILL SLOWLY WORK FROM W TO E ACROSS
THE AREA LATE THIS MORNING INTO THE AFTERNOON. THE LOW LEVEL FLOW
WILL ALSO BECOME MORE ANTICYCLONIC DURING THIS TIME PERIOD. THIS
WILL PLACE THE MOST PROBABLE TIME PERIOD FOR CLEARING DURING THE 17Z
TO 20Z TIME FRAME. THERE HAS HOWEVER BEEN SOME FAIRLY SIGNIFICANT
BREAKS ACROSS NE LOWER MI...AN AFFECT OF SOME ADDED DOWNSLOPE.
CONSIDERING THE VERY SHALLOW NATURE OF THE MOISTURE. THIS DOWNSLOPE
MAY LEAD TO MORE BREAKS IN AND AROUND MBS MUCH EARLIER. ASIDE FROM
THE CLOUDS...WINDS HAVE ACTUALLY INCREASED OVERNIGHT /GUSTING UP TO
20 KNOTS AT TIMES/. THERE WILL BE A SLOW BUT STEADY DECREASE IN THE
WINDS DURING THE MORNING AND AFTERNOON AS THE GRADIENT WEAKENS.
FOR DTW....ANY CLEARING AT METRO PRIOR TO 18Z WILL NEED SOME MORNING
BREAKS TO DEVELOP OVER NRN IND/SW LOWER MI. RECENT SATELLITE TRENDS
SUGGEST THIS IS NOT GOING TO HAPPEN. IN FACT...THE HRRR KEEPS THE
CLOUDS IN THROUGH 21Z. WHILE CERTAINLY POSSIBLE...AT THIS TIME THE
CONCERNS OF EARLIER CLEARING UPSTREAM SUGGESTS ONLY PUSHING THE
CLEARING BACK TO 19Z.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILINGS BELOW 5000 FEET THIS MORNING. LOW CONFIDENCE ON
TIMING OF CLEARING THIS AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 237 AM EST FRI DEC 4 2015
DISCUSSION...
A LARGE AREA OF SURFACE HIGH PRESSURE WILL MAINTAIN QUIET WEATHER
THROUGH THE WEEKEND AS OVERALL MID LATITUDE FLOW REMAINS INNOCUOUS
FOR EARLY DECEMBER WITH AN EVEN WEAKER SUB-TROPICAL JET LENDING
LITTLE TO NO SUPPORT FOR ANY NOTABLE JET STREAM PHASING INTO EARLY
NEXT WEEK. THIS WILL LEAD TO A LARGELY DRY WEATHER PATTERN. THE NEXT
VERY SMALL CHANCE OF RAIN WILL COME EARLY NEXT WEEK AS A SHORTWAVE
MEANDERS EASTWARD INTO THE OHIO VALLEY. THIS SYSTEM REMAINS CUT OFF
FROM THE MAIN BAND OF WESTERLIES WITH NO INDICATIONS OF PHASING WITH
THE SUB-TROPICAL JET UNTIL IT APPROACHES THE EAST COAST. SO...ANY
PRECIPITATION THAT MAY BRUSH THE AREA IS EXPECTED TO BE TRIVIAL AT
THIS TIME.
FOR TODAY...SKY CONDITIONS WILL BE THE MAIN CHALLENGE AS CLEARING
WITHIN SUBSIDENCE REGION IN WAKE OF PASSING WEAK TROUGH HAS BEEN
SLOW TO OCCUR GIVEN THE REFORMATION OF STRATUS TO THE LEE OF LAKE
MICHIGAN. AS DRIER AIR CONTINUES TO WORK INTO AREA WITH EXPANDING
SURFACE HIGH PRESSURE...STILL EXPECT SKIES TO CLEAR WITH TIME DURING
THE DAY. IT JUST MAY TAKE HALF OR MORE OF THE DAY. THIS WILL HAVE
SOME AFFECT ON TEMPERATURES...ALTHOUGH STEADY WEST TO SOUTHWEST FLOW
WILL ALLOW FOR DECENT MIXING...SO EXPECT HIGHS TO CLIMB INTO THE MID
TO UPPER 40S AS A WEAK WARM AIR ADVECTION PATTERN ENSUES AS UPPER
RIDGING EXPANDS OVER THE AREA.
MILD WEATHER WILL PERSIST THROUGH THE WEEKEND AS THIS RIDGE SLOWLY
PROGRESSES TO THE EAST COAST...BUT AREA REMAINS WITHIN SOUTHWESTERLY
UPPER LEVEL FLOW. EXPECT HIGHS IN THE MID 40S TO AROUND 50 BOTH
DAYS.
WHILE THE ABOVE AVERAGE START TO DECEMBER WILL PERSIST THROUGH MID
TO LATE NEXT WEEK...OVERALL WEATHER PATTERN BECOMES INCREASINGLY
DIFFICULT AS THE MID LATITUDE JET STREAM COMING ONSHORE OVER THE
WESTERN CONUS INCREASES SUBSTANTIALLY WITH TIME NEXT WEEK. COUPLE
THIS WITH AN GRADUAL ENHANCEMENT IN THE SUBTROPICAL JET...AND ANY
SHORTWAVE ENERGY EJECTING INTO THE PLAINS/MIDWEST WILL HAVE A MUCH
BETTER CHANCE OF DEVELOPING INTO A DECENT STORM AS COMPARED TO THE
SHORTER TERM UPPER LEVEL CONDITIONS ACROSS THE CONUS THROUGH THE
WEEKEND.
MARINE...
A TIGHTENING OF THE GRADIENT OVER LAKE HURON THIS MORNING HAS LED TO
SOME GUSTY WEST-SOUTHWEST WINDS...GUSTING OVER 25 KNOTS AT TIMES. A
SURFACE TROUGH AXIS NOW ROTATING ACROSS THE NORTHERN GREAT
LAKES...PASSING ATOP THE NORTHERN PERIPHERY OF STRONG HIGH PRESSURE
CENTERED OVER THE MID MISSISSIPPI VALLEY...IS SUSTAINING THIS GRADIENT.
THIS TROUGH AXIS WILL TRACK EAST OF THE REGION TODAY. THE SURFACE
HIGH WILL THEN EXPAND NORTHWARD INTO THE GREAT LAKES. THIS ALONG
WITH LOW LEVEL WARM AIR ADVANCING ACROSS THE LAKES WILL LEAD TO A
STEADY DECREASING TREND IN WINDS AND WAVES TODAY. THE HIGH WILL
DRIFT TO THE MID ATLANTIC DURING THE COURSE OF THE WEEKEND...PLACING
LAKE HURON WITHIN A SOUTH-SOUTHWESTERLY RETURN FLOW. THE WARM LOW
LEVEL AIR WILL HINDER MIXING POTENTIAL OVER THE LAKES...SO GUSTS ARE
EXPECTED TO REMAIN LARGELY UNDER 20 KNOTS. HIGH PRESSURE WILL EXPAND
BACK ACROSS THE GREAT LAKES EARLY NEXT WEEK...PROVIDING FAIRLY LIGHT
WINDS MONDAY INTO AT LEAST TUESDAY.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......CB
AVIATION.....SC
DISCUSSION....DG
MARINE.......SC
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS RALEIGH NC
947 AM EST FRI DEC 4 2015
.SYNOPSIS...HIGH PRESSURE WILL BUILD INTO CENTRAL NC TODAY...THEN
LINGER OVERHEAD THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 945 AM FRIDAY...
WATER VAPOR SHOWED VERY DRY MID-LEVEL AIR OVER CENTRAL NORTH
CAROLINA...AND RAP SOUNDINGS SHOW DRY AIR CONTINUING THROUGH THE
COLUMN THROUGH TODAY...AND INTO TONIGHT. ALTHOUGH THERE IS A
WEAKNESS IN HEIGHTS ALOFT AND A MODEST SHEAR AXIS IN PLACE AS ALSO
NOTED ON WATER VAPOR AND ON THE FORECAST GUIDANCE...K INDICES ARE
VERY NEGATIVE AND SUBSIDENCE PREVAILS. CIRRUS WAS FINALLY MOVING OFF
TO THE EAST AS THE UPPER- AND MID-LEVEL JETS MOVE EAST...WHICH BY
THE MID AFTERNOON SHOULD BE AT OR JUST OFF OF THE NORTH CAROLINA
COAST. A FEW GUSTS WITH MIXING IN THE TEENS KNOTS...TO EARLY
AFTERNOON...SHOULD GRADUALLY SUBSIDE WITH LIGHT WINDS THROUGHOUT
CENTRAL NORTH CAROLINA BY EVENING. HIGHEST GUSTS IN A RELATIVE SENSE
SHOULD BE TOWARD KFAY...KCTZ... KGSB...AND KRWI WHERE THE SURFACE
GRADIENT IS JUST SLIGHTLY TIGHTER AND 925MB WINDS ARE
STRONGER...THOUGH THESE SUBSIDE TO LESS THAN 10KT THIS AFTERNOON.
TEMPERATURES HAVE RISEN QUICKLY WITH SUN EARLY THIS MORNING AND
OPTED TO RAISE MAXES IN MOST LOCATIONS BUT JUST A DEGREE OR
TWO...CLOSER TO THE MAV MOS GUIDANCE AND IN CONJUNCTION WITH VALUES
NOTED BY 1000-850MB THICKNESSES.
DRY AND SEASONABLY COOL CONDITIONS CONTINUE THROUGH SATURDAY. MIN
TEMPS TONIGHT WILL MAINLY BE NEAR OR SLIGHTLY BELOW FREEZING THOUGH
THE NORMALLY COLDER LOCATIONS WILL BE IN THE UPPER 20S. HIGH
TEMPERATURES SATURDAY WILL AVERAGE A DEGREE OR TWO WARMER...MID
TO UPPER 50S.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 320 AM FRIDAY...
HIGH PRESSURE AT THE SURFACE AND ALOFT WILL REMAIN OVERHEAD SATURDAY
NIGHT THROUGH SUNDAY THEN DRIFT EAST AND WEAKEN SUNDAY NIGHT. THE
LOW LEVEL AIR MASS WILL CONTINUE TO MODIFY...SUPPORTING HIGH TEMPS
SUNDAY WELL INTO THE 50S TO AROUND 60. STILL CHILLY SATURDAY NIGHT
WITH MIN TEMPS NEAR FREEZING...UPPER 20S AT THE NORMALLY COLDER
LOCATIONS. INCREASING MOISTURE THROUGH THE COLUMN WILL RESULT IN
"WARMER" OVERNIGHT TEMPS IN THE 30S TO AROUND 40. BASED ON MODEL
TRENDS OF A SLOWER ARRIVAL OF DEEPER MOISTURE AND ENOUGH LIFT TO
GENERATE LIGHT PRECIP...HAVE REMOVED THE MENTION OF SLIGHT CHANCE
POPS FROM THE FORECAST FOR SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 225 AM FRIDAY...
MONDAY THROUGH TUESDAY: MEDIUM RANGE MODELS CONTINUE TO STRUGGLE
WITH THE TRACK AND TIMING OF A MID LEVEL LOW EXPECTED TO SHIFT
EASTWARD FROM THE TN/OH VALLEY REGION MONDAY MORNING TO OFF THE MID
ATLANTIC COAST BY AT LEAST TUESDAY EVENING. BOTH THE ECMWF AND GFS
HAVE TRENDED NORTHWARD WITH THE TRACK OF THE MID LEVEL LOW THOUGH...
AND FURTHER OFFSHORE WITH A DEVELOPING COASTAL LOW DURING THIS TIME
FRAME. THIS WOULD RESULT IN LESS OF A CHANCE OF RAIN ON MONDAY INTO
TUESDAY FOR CENTRAL NC. HOWEVER... GIVEN THE DRAMATIC SHIFT IN THE
OPERATIONAL RUNS OF THE GFS AND ECMWF OVER THE LAST 24 HOURS WILL
CONTINUE TO HOLD ONTO SOME LOW END CHANCE POPS FOR MONDAY INTO
MONDAY NIGHT... WITH THE BEST CHANCE ACROSS THE SOUTHEAST/EASTERN
PORTIONS OF CENTRAL NC (GENERALLY EAST OF RALEIGH). GIVEN THIS TREND
IN THE MODELS WILL RAISE HIGH TEMPS SOME FOR MONDAY AND KEEP HIGHS
SIMILAR FOR TUESDAY. THIS YIELDS HIGHS IN THE MID TO UPPER 50S...
WITH EVEN A FEW LOCATIONS POSSIBLY TOUCHING 60. LOW TEMPS TUESDAY
MORNING ARE EXPECTED TO RANGE FROM THE MID 30S NW TO THE LOWER TO
MID 40S SE (DEPENDING ON THE AMOUNT OF CLOUD COVER AND POSSIBLE
PRECIP). OVERALL... HAVE TREND THE FORECAST MORE TO THE LAST TWO
RUNS OF THE ECMWF... GIVEN BETTER RUN TO RUN CONTINUITY.
TUESDAY NIGHT THROUGH THURSDAY: AFTER A BRIEF PERIOD OF MID LEVEL
S/W RIDGING... MEDIUM RANGE MODELS STRUGGLE WITH A FAIRLY
PROGRESSIVE PATTERN OF FAST MOVING MID LEVEL DISTURBANCES IN A
GENERAL MEAN L/W BROAD TROUGH ACROSS THE EASTERN HALF OF THE
COUNTRY. GIVEN THESE HARD TO TIME DISTURBANCES EXPECTED TO MOVE
ACROSS THE REGION DURING THIS TIME FRAME... WILL KEEP TEMPS NEAR
NORMAL AS LOW LEVEL THICKNESS VALUES ARE PROGGED TO REMAIN NEAR
NORMAL. THIS YIELDS HIGHS IN THE MID TO UPPER 50S GENERALLY... WITH
LOWS IN THE 30S TO NEAR 40 SE... AND DRY CONDITIONS FOR NOW.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 635 AM FRIDAY...
THERE IS HIGH CONFIDENCE THAT VFR CONDITIONS WILL EXISTS ACROSS
CENTRAL NC THROUGH SUNDAY. HIGH PRESSURE WILL BUILD INTO THE REGION
TODAY...AND SETTLE OVERHEAD THROUGH THE WEEKEND. SFC WINDS LATER
TODAY WILL BE NORTH-NORTHEAST BETWEEN 07-12KTS...BECOMING LIGHT AND
VARIABLE THIS EVENING.
FORECAST CONFIDENCE LOWERS EARLY NEXT WEEK AS THE MODELS HAVE BEEN
INCONSISTENT IN ITS HANDLING OF AN AREA OF LOW PRESSURE APPROACHING
OUR REGION. STILL...THERE IS POTENTIAL FOR A BRIEF PERIOD OF SUB VFR
CEILINGS MONDAY INTO EARLY TUESDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MLM
NEAR TERM...WSS/DJF
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
921 AM CST FRI DEC 4 2015
.UPDATE...
ISSUED AT 920 AM CST FRI DEC 4 2015
THE MAIN CHALLENGE WILL BE TEMPS AND WINDS. WINDS MAY APPROACH
ADVISORY LEVELS LATE THIS AFTERNOON THROUGH ABOUT 6Z IN THE
VALLEY...WHEN 925MB WINDS INCREASE TO ABOUT 60KT. THERE WILL BE A
VERY STEEP INVERSION SO MIXING THESE WINDS WILL BE TOUGH...BUT IF
WE CAN WARM TO AROUND 40 THEN WE SHOULD MIX AT LEAST 45KT OR SO.
THE SNOW FREE AREAS WILL LIKELY HAVE THE STRONGEST WINDS...SO WE
WILL INCREASE WINDS TO NEAR ADVISORY LEVELS AND CONTINUE TO
MONITOR...WITH GUSTS TO AT LEAST 40MPH LATER TODAY/THIS EVENING.
TEMPS LOOK GOOD AND WE WON/T ADJUST THEM MUCH AT ALL WITH PLENTY
OF SUNSHINE AND INCREASING WINDS HELPING MIX SOME WARM AIR DOWN.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 325 AM CST FRI DEC 4 2015
MAIN FORECAST CHALLENGE WILL BE TEMPERATURES. GOOD AGREEMENT WITH
MODELS ON MAIN DETAILS.
TEMPERATURES WILL BE THE PRIMARY CHALLENGE THROUGH THE PERIOD
BETWEEN AREAS WITH SNOW COVER VS NO SNOW. OVER A 20 DEGREES SPREAD
IN MAXIMUM TEMPERATURES YESTERDAY BASED JUST ON SNOW COVER. THIS
TREND WILL LIKELY CONTINUE AS LONG AS SNOW COVER EXISTS.
FOR TODAY SURFACE PRESSURE GRADIENT INCREASES FOR BREEZY
CONDITIONS HOWEVER WITH VERY SHALLOW MIXED LAYER STRONGER WINDS
ALOFT NOT LIKELY TO MIX DOWN. WARM COLUMN REMAINS IN PLACE SO MILD
TEMPERATURES TO CONTINUE. DIFFERENCE TODAY FROM YESTERDAY WILL BE
SOUTHERLY VS WESTERLY SURFACE WINDS. A SOUTH WIND COMING ACROSS
SNOW FIELD MAY SOMEWHAT LIMIT TEMPERATURE CLIMB ACROSS SNOW FREE
REGION ACROSS THE NORTHERN FA. MODEL GUIDANCE HAS STRUGGLED WITH
TEMPERATURES AS A RESULT OF SNOW COVER. RUC APPEARED MOST
REALISTIC WITH TEMPERATURES SO GENERALLY FOLLOWED ITS FORECAST.
NORTHERN AREAS MAY STAY JUST SHY OF 50 WITH REMAINDER OF FA
HOLDING IN THE 30S TO AROUND 40.
MIXING WILL HOLD TEMPERATURES UP TONIGHT WITH MINIMUMS AT OR ABOVE
AVERAGE HIGHS FOR THIS TIME OF THE YEAR.
BROAD MID LEVEL TROUGH WILL CROSS THE FA THIS WEEKEND. A WEAK COLD
FRONT WILL CROSS THE REGION SATURDAY. COLUMN LACKING MOISTURE SO A
BIT MORE CLOUD COVER AND WSHFT WILL BE THE ONLY AFFECTS WITH
FROPA. COLUMN COOLER SO TEMPERATURES MAY BE MORE UNIFORM ACROSS
THE FA BUT STILL WELL ABOVE AVERAGE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 AM CST FRI DEC 4 2015
MINIMAL WEATHER IMPACTS WILL CONTINUE REMAINDER OF THE WEEKEND.
WELL ABOVE AVERAGE TEMPERATURES WILL CONTINUE TO WORK ON SHRINKING
EXISTING SNOW PACK. APPEARS TO BE ENOUGH MIXING TO LIMIT NIGHT
TIME FOG DEVELOPMENT WITH DAY TIME MELTING BUT WILL NEED TO
MONITOR.
MODELS INITIALIZED WELL AND CONTINUE TO SHOW A GENERAL BROAD RIDGE
ACROSS THE NRN PLAINS. WITH THE UPPER RIDGE REMAINING IN
PLACE...EXPECT TEMPERATURES TO REMAIN ABOVE NORMAL. HOWEVER...TEMPS
WILL DEPEND ON ANY REMAINING SNOW PACK...AND INDICATIONS ARE IT WILL
CONTINUE TO ERODE...AS HIGH TEMPS LOOK TO BE IN THE UPPER 30S TO LOW
40S THRU THE PERIOD. OTHERWISE...A FEW IMPULSES OF ENERGY WILL
PROPAGATE THRU THE FLOW...BUT WITH A GENERALLY DRY COLUMN DO NOT
ANTICIPATE MUCH IN THE WAY OF PCPN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 620 AM CST FRI DEC 4 2015
WILL SEE INCREASING SOUTH WINDS TODAY OTHERWISE VFR CONDITIONS
EXPECTED WITH NO CIGS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...VOELKER
LONG TERM...HOPKINS/VOELKER
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
622 AM CST FRI DEC 4 2015
.UPDATE...
ISSUED AT 620 AM CST FRI DEC 4 2015
NO UPDATE NECESSARY.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 325 AM CST FRI DEC 4 2015
MAIN FORECAST CHALLENGE WILL BE TEMPERATURES. GOOD AGREEMENT WITH
MODELS ON MAIN DETAILS.
TEMPERATURES WILL BE THE PRIMARY CHALLENGE THROUGH THE PERIOD
BETWEEN AREAS WITH SNOW COVER VS NO SNOW. OVER A 20 DEGREES SPREAD
IN MAXIMUM TEMPERATURES YESTERDAY BASED JUST ON SNOW COVER. THIS
TREND WILL LIKELY CONTINUE AS LONG AS SNOW COVER EXISTS.
FOR TODAY SURFACE PRESSURE GRADIENT INCREASES FOR BREEZY
CONDITIONS HOWEVER WITH VERY SHALLOW MIXED LAYER STRONGER WINDS
ALOFT NOT LIKELY TO MIX DOWN. WARM COLUMN REMAINS IN PLACE SO MILD
TEMPERATURES TO CONTINUE. DIFFERENCE TODAY FROM YESTERDAY WILL BE
SOUTHERLY VS WESTERLY SURFACE WINDS. A SOUTH WIND COMING ACROSS
SNOW FIELD MAY SOMEWHAT LIMIT TEMPERATURE CLIMB ACROSS SNOW FREE
REGION ACROSS THE NORTHERN FA. MODEL GUIDANCE HAS STRUGGLED WITH
TEMPERATURES AS A RESULT OF SNOW COVER. RUC APPEARED MOST
REALISTIC WITH TEMPERATURES SO GENERALLY FOLLOWED ITS FORECAST.
NORTHERN AREAS MAY STAY JUST SHY OF 50 WITH REMAINDER OF FA
HOLDING IN THE 30S TO AROUND 40.
MIXING WILL HOLD TEMPERATURES UP TONIGHT WITH MINIMUMS AT OR ABOVE
AVERAGE HIGHS FOR THIS TIME OF THE YEAR.
BROAD MID LEVEL TROUGH WILL CROSS THE FA THIS WEEKEND. A WEAK COLD
FRONT WILL CROSS THE REGION SATURDAY. COLUMN LACKING MOISTURE SO A
BIT MORE CLOUD COVER AND WSHFT WILL BE THE ONLY AFFECTS WITH
FROPA. COLUMN COOLER SO TEMPERATURES MAY BE MORE UNIFORM ACROSS
THE FA BUT STILL WELL ABOVE AVERAGE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 AM CST FRI DEC 4 2015
MINIMAL WEATHER IMPACTS WILL CONTINUE REMAINDER OF THE WEEKEND.
WELL ABOVE AVERAGE TEMPERATURES WILL CONTINUE TO WORK ON SHRINKING
EXISTING SNOW PACK. APPEARS TO BE ENOUGH MIXING TO LIMIT NIGHT
TIME FOG DEVELOPMENT WITH DAY TIME MELTING BUT WILL NEED TO
MONITOR.
MODELS INITIALIZED WELL AND CONTINUE TO SHOW A GENERAL BROAD RIDGE
ACROSS THE NRN PLAINS. WITH THE UPPER RIDGE REMAINING IN
PLACE...EXPECT TEMPERATURES TO REMAIN ABOVE NORMAL. HOWEVER...TEMPS
WILL DEPEND ON ANY REMAINING SNOW PACK...AND INDICATIONS ARE IT WILL
CONTINUE TO ERODE...AS HIGH TEMPS LOOK TO BE IN THE UPPER 30S TO LOW
40S THRU THE PERIOD. OTHERWISE...A FEW IMPULSES OF ENERGY WILL
PROPAGATE THRU THE FLOW...BUT WITH A GENERALLY DRY COLUMN DO NOT
ANTICIPATE MUCH IN THE WAY OF PCPN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 620 AM CST FRI DEC 4 2015
WILL SEE INCREASING SOUTH WINDS TODAY OTHERWISE VFR CONDITIONS
EXPECTED WITH NO CIGS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...VOELKER
LONG TERM...HOPKINS/VOELKER
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
904 AM EST FRI DEC 4 2015
.SYNOPSIS...
SURFACE HIGH PRESSURE OVER THE MID MISSISSIPPI VALLEY WILL MOVE
SLOWLY EAST ACROSS THE OHIO VALLEY AND MOVE OFF THE MID ATLANTIC
COAST SUNDAY. THIS WILL ALLOW AN UPPER LEVEL TROUGH TO MOVE
ACROSS THE OHIO VALLEY EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...LOW STRATUS TRAPPED UNDER AN INVERSION REMAINS STUCK
ACROSS THE AREA THIS MORNING. THERE IS A DRY SLOT WITH THE EDGE
FROM ROUGHLY KCMH TO KYNG. HOWEVER THE CLOUD LINE IS EITHER
STATIONARY OR DRIFTING SLOWLY EAST. BIG QUESTION IS WHETHER IT
ERODES TOWARD THE WEST OR CONTINUES TO DRIFT SLOWLY EAST AS IT
ERODES. GIVEN THE STRENGTH OF THE INSOLATION (INCOMING SOLAR
RADIATION)...AM NOT OPTIMISTIC. ON THE OTHER SIDE...THE WESTERN
EDGE IS WELL WEST AND NORTHWEST ALONG THE LAKE MICHIGAN SHORE.
FOLLOWING THE HRRR THIS DRIFTS EAST-SOUTHEAST WITH CLEARING INTO
NWRN OHIO MID/LATE AFTERNOON. THE BIG TAKE HERE IS THAT FOR MOST
OF THE AREA...CLOUDS WILL LIKELY BE THE FLAVOR OF THE DAY.
ORIGINAL DISCUSSION...
FORECAST PROBLEM OF THE DAY IS HOW FAST THE CLOUD DECK ACROSS THE
CENTRAL AND EASTERN LAKES WILL ERODE. NONE OF THE MODELS HAVE A
CLUE ABOUT THE CLOUD COVER SINCE INVERSION TRAPPING MOISTURE BELOW
925MB. THERE ARE A FEW CLOUD BREAKS NOW...BUT THE 925 MB RIDGE AXIS
DOESNT REACH NW OHIO UNTIL THIS AFTERNOON SO HAVE SLOWED THE TIMING
OF THE CLOUD DECK UNTIL THIS AFTERNOON. IN FACT DO NOT THINK THE
EAST WILL TOTALLY CLEAR OUT UNTIL TONIGHT. AS A RESULT LOWER
FORECAST HIGHS A FEW DEGREES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
LAST REMAINING CLOUDS IN THE EAST SHOULD CLEAR OUT OVERNIGHT AS
THE RIDGE FINALLY MOVES OVER THE FORECAST AREA. SURFACE RIDGE
SHIFTS EAST OF THE AREA SATURDAY ALLOWING FOR A WARMUP. TEMPS
SHOULD WARM INTO THE UPPER 40S TO LOWER 50S THIS WEEKEND...WHICH
IS ROUGHLY 5-10 DEGREES ABOVE NORMAL FOR EARLY DECEMBER. MODELS
CONTINUE TO MOVE THE HIGH OFF THE MID ATLANTIC COAST EARLY SUNDAY.
THIS WILL ALLOW AN UPPER LEVEL TROUGH TO MOVE ACROSS THE OHIO
VALLEY ON MONDAY. BEST MOISTURE REMAINS WELL SOUTH OF THE FORECAST
AREA SO WILL CONTINUE WITH A DRY FORECAST THROUGH THE PERIOD.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
UNUSUALLY QUIET WEATHER WILL CONTINUE DURING THE LONG TERM PERIOD AS
HIGH PRESSURE AT THE SURFACE IS EXPECTED TO DOMINATE. HAVE MADE
ONLY MINOR CHANGES TO THE FORECAST. SOME MODEL DIFFERENCES BEGIN TO
CROP UP AT THE VERY END OF THE FORECAST PERIOD BUT WILL LET LATER
SHIFTS DEAL WITH THAT. TEMPERATURES DURING THE PERIOD WILL AVERAGE
5 TO 10 DEGREES ABOVE NORMAL WITH PARTLY CLOUDY SKIES MUCH OF THE
TIME.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
A SMALL AREA OF CLEARING HAS MADE IT`S WAY TO NE OHIO. IT SHOULD
LINGER OVER KCAK FOR ANOTHER HOUR AND AT KYNG FOR A COUPLE OF
HOURS. AFTER THAT IFR/MVFR CIGS WILL OVERSPREAD THE AREA AGAIN. IT
REMAINS VERY DRY ALOFT BUT THE BOUNDARY LAYER IS MOIST. TILL WE
GET ENOUGH MIXING THE LOW CLOUDS WILL PERSIST. BEST GUESS NOW IS
THAT THE CLOUDS WILL BEGIN TO BREAK UP AROUND MIDDAY. WILL KEEP
THE WESTERN SITES IFR TILL THEN AND BRING IFR INTO KCAK AND KYNG
IN A FEW HOURS. THERE SHOULD BE JUST ENOUGH DOWNSLOPING SW FLOW TO
KEEP CIGS AT KCLE AND KERI MVFR. ONCE THE CLOUDS BREAK UP SKIES
THE REMAINDER OF THE PERIOD SHOULD BE MAINLY CLEAR. SW TO WSW FLOW
WILL CONTINUE. WINDS SHOULD GRADUALLY LESSEN TODAY.
OUTLOOK...VFR CONDITIONS INTO EARLY NEXT WEEK AS HIGH PRESSURE
REMAINS IN CONTROL.
&&
.MARINE...
NO SIGNIFICANT CHANGES TO THE MARINE FORECASTS THIS
MORNING. MARGINAL SMALL CRAFT CONDITIONS WILL CONTINUE IN THE EAST
TODAY SO WILL LEAVE THE HEADLINES AS IS. HIGH PRESSURE WILL BUILD
OVER THE LAKE FROM THE SOUTH OVER THE WEEKEND. THIS WILL MAINTAIN A
LIGHT W TO SW FLOW. THE HIGH WILL EVENTUALLY LIFT OFF TO THE
NORTHEAST EARLY NEXT WEEK WITH VARIABLE FLOW UNDER 15 KNOTS
CONTINUING.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
LEZ147>149.
&&
$$
SYNOPSIS...DJB
NEAR TERM...DJB/TK
SHORT TERM...DJB
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1225 PM EST FRI DEC 4 2015
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO INFLUENCE OUR WEATHER THROUGH THE
WEEKEND BEFORE MOVING OFFSHORE LATE SUNDAY INTO MONDAY. A LOW
PRESSURE SYSTEM IS FORECAST TO DEVELOP ALONG THE MID ATLANTIC COAST
ON MONDAY, THEN TRACK NORTHEAST TUESDAY AND WEDNESDAY WHILE
REMAINING OFFSHORE. HIGH PRESSURE WILL NOSE DOWN FROM THE NORTH FOR
WEDNESDAY AND THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A VERY NICE DAY WITH SURFACE HIGH PRESSURE PUSHING IN FROM THE
WEST. AFTERNOON TEMPS WILL BE ABOUT NORMAL WITH FULL SUN. WELL,
WE WENT WITH THE HRRR EARLIER THIS MORNING AND ADDED A FEW MORE
CLOUDS BACK INTO THE GRIDS ACROSS THE NORTHERN AND WESTERN ZONES.
FOR THIS UPDATE, WE`RE GOING TO REMOVE THEM. THE SUBSIDENCE HAS
ARRIVED.
PREVIOUS DISCUSSION
WITH THE FORECAST ON TRACK, THERE WAS MINIMAL GRID WORK WITH THIS
UPDATE. I DID CHANGE SOME SPURIOUS TEMP/DEWPOINT GRIDS WHICH ALSO
AFFECTED A COUPLE OF OTHER RELATED GRIDS AS WELL.
SOME OF THE SKY GRIDS WERE ADJUSTED. THE VIS SAT PIC DOES SHOW
STRATOCU DISSIPATING, AS FORECAST, ACROSS THE LEHIGH VALLEY, SE
PA, AND WESTERN NJ. BUT WE FEEL THE CLOUDS WILL HANG ON FURTHER
INTO THE DAY ACROSS THE POCONOS AND NW NJ.
PREVIOUS DISCUSSION...
UPPER LEVEL SHORT WAVE RIDGE OVER THE NORTHERN PLAINS NOW WILL SLIDE
EAST INTO THE GREAT LAKES REGION BY THE END OF THE DAY. AT THE SAME
TIME, THE SURFACE HIGH, CURRENTLY CENTERED OVER KENTUCKY AND
INDIANA, WILL STRENGTHEN.
WHAT THIS MEANS FOR OUR REGION IS TRANQUIL WEATHER. THE MID LEVEL
CLOUDS OVER THE WESTERN PORTIONS OF THE REGION NOW, COULD PERSIST
THROUGH EARLY THIS AFTERNOON, AS MID LEVEL NORTHWESTERLY FLOW
CONTINUES. HOWEVER, BY MID AFTERNOON, SUBSIDENCE SHOULD LEAD TO
CLEARING SKIES. HIGHS SHOULD RANGE FROM THE LOWER 40S (GENERALLY
OVER THE POCONOS WHERE THE CLOUDS WILL BE SLOWER TO DISSIPATE) TO
THE LOWER 50S OVER THE COASTAL PLAINS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
HIGH SLIDES A BIT CLOSER TO THE REGION TONIGHT, LEADING TO CLEARING
SKIES AND SUBSIDENCE. AS SUCH, EXPECT PRIME RADIATIONAL COOLING
CONDITIONS FOR TONIGHT. THUS, WENT ON THE LOWER SIDE OF GUIDANCE,
WITH LOWS RANGING FROM THE MID 20S TO MID 30S.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
STRONG HIGH PRESSURE WILL CONTINUE TO INFLUENCE OUR WEATHER THROUGH
THIS WEEKEND. THE HIGH WILL CREST OVER THE AREA ON SUNDAY AND THEN
START TO PUSH TO THE EAST LATE SUNDAY, FINALLY MOVING FULLY OFFSHORE
BY EARLY MONDAY. THE WEATHER SHOULD REMAIN DRY AND SKIES WILL REMAIN
CLOUDLESS FOR THE MOST PART AS SUBSIDENCE INCREASES ACROSS THE AREA
UNDER THE RIDGE.
THE NEXT PART OF THE EXTENDED IS STILL A BIT UNCERTAIN BUT THE
MODELS ARE STARTING TO COME TOGETHER ON A MORE OFFSHORE SCENARIO FOR
THE POTENTIAL COASTAL LOW. THERE IS STILL A GOOD DEAL OF DIFFERENCE
IN THE TIMING AND STRENGTH OF THE LOW AS WELL AS JUST WHERE IT MAY
FORM OFFSHORE. THE 00Z GFS IS MUCH CLOSER TO THE COAST AND FORMS THE
LOW FURTHER TO THE SOUTH AND CLOSER TO THE COAST THAN THE 00Z ECMWF
AND AS A RESULT SHOWS MORE OF AN IMPACT ACROSS OUR AREA.
EVEN THOUGH THE GUIDANCE APPEARS TO BE TRENDING TO THE EAST WITH THE
LOW, IT DOES NOT MEAN THAT WE WILL BE OUT OF THE WOODS. THERE WILL
REMAIN A RISK FOR SOME HEAVY RAINS AND GUSTY WINDS, WHICH WOULD BE
MORE LIKELY ACROSS OUR SOUTHERN ZONES AND ALONG THE COASTAL AREAS.
ANY SHIFT TO THE WEST WOULD CERTAINLY INCREASE THE CHANCES INLAND.
WITH A POTENTIALLY STRONG NORTHEASTERLY FLOW, WE WOULD ALSO NEED TO
MONITOR ANY COASTAL CONCERNS.
SHOWERS ARE EXPECTED TO START MOVING INTO THE AREA LATER MONDAY,
MAINLY ONLY INTO OUR SOUTHERN ZONES, WITH A FEW SHOWERS POSSIBLE BY
LATE AFTERNOON. FOR THE MOST PART, THE SHOWERS WILL CONFINED CLOSER
TO THE COAST WITH DECREASING CHANCES AS YOU MOVE FURTHER INLAND.
HOWEVER, THIS IS HIGHLY DEPENDENT ON JUST HOW CLOSE THE LOW REMAINS
TO THE COAST AND HOW MUCH IT INTENSIFIES AS IT MOVES TO THE NORTH
AND EAST. OVERALL, EXPECT SHOWERS TO START TO DECREASE ACROSS THE
REGION LATE TUESDAY INTO WEDNESDAY WITH WEDNESDAY EXPECTED TO BE A
MOSTLY DRY DAY.
ONCE THE LOW PUSHES FURTHER EAST, WE SHOULD SEE A (BRIEF) RETURN TO
HIGH PRESSURE. BOTH THE GFS AND THE ECMWF SHOW HIGH PRESSURE NOSING
IN FROM THE NORTH WITH A MID LEVEL WAVE CROSSING THE AREA WEDNESDAY
INTO THURSDAY. IT`S AT THIS POINT WE START TO SEE SOME CONSIDERABLE
DIFFERENCES IN THE MODELS. THE GFS KEEPS HIGH PRESSURE OVER US AS WE
HEAD INTO THE WEEKEND WHILE THE ECMWF TRACKS A DISTURBANCE ACROSS THE
REGION LATE THURSDAY INTO FRIDAY. BOTH MODELS SHOW THAT A MID LEVEL
LOW WILL TRACK TOWARDS THE REGION BUT THE LOCATION OF THE LOW
DIFFERS WHICH LEADS TO THE VARYING SOLUTIONS. PLENTY OF TIME TO SEE
HOW THESE FEATURES MAY UNFOLD.
&&
.AVIATION /17Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY, AND SURROUNDING AREAS.
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. A CLOUD DECK
AROUND 3000 TO 4000 FT AGL COULD PERSIST THROUGH 18Z, BUT AFTER
THAT, FEW, IF ANY, CLOUDS ARE EXPECTED.
WIND DIRECTION MAY VARY BETWEEN WESTERLY AND NORTHWESTERLY THROUGH
THE TAF PERIOD, BUT WIND SPEEDS WILL GENERALLY BE NEAR OR BELOW
10KT, THOUGH A FEW GUSTS TO 15 KT ARE POSSIBLE BETWEEN 15 AND 21Z.
OUTLOOK...
SATURDAY THROUGH SUNDAY...MAINLY VFR CONDITIONS EXPECTED. NORTHWEST
WINDS AROUND 5 TO 10 KNOTS, BECOMING WEST TO SOUTHWEST ON SUNDAY.
MONDAY...MAINLY VFR CONDITIONS EXPECTED. NORTHWEST WINDS EARLY,
BECOMING NORTH TO NORTHEAST THROUGH THE DAY. WIND SPEEDS AROUND 5 TO
10 KNOTS.
TUESDAY...NORTHEAST WINDS EXPECTED WITH 20 KT GUSTS POSSIBLE,
ESPECIALLY CLOSER TO THE COAST. SUB-VFR CONDITIONS POSSIBLE IN
RAIN AS A COASTAL SYSTEM PASSES OFF THE MID ATLANTIC COAST.
&&
.MARINE...
WINDS AND SEAS SHOULD STAY BELOW SMALL CRAFT ADVISORY CONDITIONS
TODAY AND TONIGHT. A FEW GUSTS ABOVE 20 KT WILL BE POSSIBLE
THROUGH SUNRISE, BUT WINDS WILL CONTINUE TO SLOWLY SUBSIDE THROUGH
THE MORNING HOURS.
OUTLOOK...
SATURDAY THROUGH SUNDAY...EXPECT WINDS AND SEAS TO REMAIN BELOW
SMALL CRAFT ADVISORY CRITERIA THROUGH SUNDAY.
MONDAY...A NORTH TO NORTHEAST FLOW WILL DEVELOP ACROSS THE REGION
AND WINDS WILL GRADUALLY INCREASE, WITH POTENTIAL GUSTS AROUND 25
KNOTS LATE MONDAY NIGHT INTO EARLY TUESDAY. SEAS WILL ALSO START TO
BUILD BUT SHOULD REMAIN BELOW 5 FEET ON MONDAY.
TUESDAY...NORTHEAST WINDS WILL INCREASE AND GUSTS WILL EXCEED 25
KNOTS ON TUESDAY AS LOW PRESSURE IS FORECAST TO ORGANIZE TO THE
SOUTH OF OUR WATERS. SEAS WILL RISE IN THE EASTERLY FLOW AND ARE
EXPECTED TO START REACHING 5 FEET LATER ON TUESDAY.
AT THIS TIME, A SMALL CRAFT ADVISORY LOOKS LIKE IT WILL LIKELY BE
NEEDED. HOWEVER, UNCERTAINTY WITH THE TIMING, STRENGTH, AND
POSITION OF THE LOW WILL HAVE A DIRECT EFFECT ON OUR AREA WATERS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MEOLA
NEAR TERM...JOHNSON/KRUZDLO
SHORT TERM...JOHNSON
LONG TERM...MEOLA
AVIATION...JOHNSON/NIERENBERG/MEOLA
MARINE...JOHNSON/NIERENBERG/MEOLA
AREA FORECAST DISCUSSION
NWS MIAMI FL
1251 PM EST FRI DEC 4 2015
.AVIATION...
AFTER A BRIEF LULL LATE THIS MORNING...SHOWERS ARE AGAIN SPREADING
NORTHWESTWARD OVER MIAMI-DADE TERMINALS...AND WILL LIKELY IMPACT
BROWARD TAF SITES BY 19Z. THUS...SHRA IN FORECAST THROUGH THIS
EVENING EAST COAST...THEN COVERAGE SHOULD BECOME MORE SCATTERED
AND WENT WITH PREVAILING VCSH FOR DURATION OF PERIOD. NAPLES MAY
NOT RECEIVE MUCH ADDITIONAL SHOWERS...BUT LOW CIGS...AT LEAST
MVFR...ARE EXPECTED TO PERSIST INTO SATURDAY MORNING. FOR EASTERN
TERMINALS...PERIODS OF MVFR ARE EXPECTED...BUT THINK VFR
CONDITIONS WILL BE MORE DOMINANT...SO WENT WITH ONLY TEMPO MVFR
CIGS FOR REMAINDER OF TODAY. WIND 5-10 KT TODAY WILL BECOME NE
AROUND 10 KT TONIGHT AND SATURDAY.
&&
.PREV DISCUSSION... /ISSUED 1007 AM EST FRI DEC 4 2015/
UPDATE...
RAIN COVERAGE ACROSS SOUTH FLORIDA IS FINALLY BEGINNING TO
SUBSIDE. WATER VAPOR IMAGERY SHOWING THE DEEPER MOISTURE HAS MOVED
OFFSHORE. THE RAP13 ANALYSIS OF THE UPPER LEVEL WIND SHOWING THE
BEST DIVERGENCE ALOFT HAS MOVED TO THE SOUTHEAST, WHICH
CORRESPONDS TO THE BETTER RAIN COVERAGE, AS WELL AS THE HEAVIER
SHOWERS AND THUNDERSTORMS. THE HRRR HAS BEEN HANDLING THE COVERAGE
FAIRLY WELL AND HAS MOST OF THE RAIN ENDING, EXCEPT FOR SOME
SHOWER ACTIVITY REDEVELOPING IN THE LAKE REGION. HAVE BROUGHT
POPS DOWN SOME, BUT HAVE LEFT LIKELY POPS IN THE FORECAST FOR MOST
OF THE ATLANTIC COASTAL METRO AREAS, ESPECIALLY FROM BROWARD,
NORTH.
PREV DISCUSSION... /ISSUED 729 AM EST FRI DEC 4 2015/
AVIATION...
WIDESPREAD RAIN AND SHOWERS LOOK TO CONTINUE THROUGH MUCH OF THE
DAY. PERIODS OF SIGNIFICANT RESTRICTIONS ARE POSSIBLE...BUT
MAJORITY OF TIME EXPECT VFR CONDITIONS. EAST WIND AROUND 10 KT
THROUGH THE PERIOD.
PREV DISCUSSION... /ISSUED 400 AM EST FRI DEC 4 2015/
DISCUSSION...
COLD FRONT EARLY THIS MORNING WAS ALIGNED FROM MAINLAND MONROE
COUNTY TO NORTHERN BROWARD COUNTY. THIS FRONT IS FORECAST TO SAG
SLOWLY SOUTHEASTWARD AND BE POSITIONED OFF THE SOUTHEAST FLORIDA
COAST TONIGHT. HIGH PRESSURE BUILDING NORTH OF THE FRONT WILL LEAD
TO INCREASING NORTHEASTERLY WINDS FROM N-S BEHIND THIS FRONT.
DEEP TROPICAL MOISTURE WILL CONTINUE ACROSS BROWARD/MIAMI-DADE
NEAR THE FRONTAL BOUNDARY TODAY-TONIGHT BEFORE DRIER AIR MOVES IN
FROM THE NORTHWEST. GPS MET DATA SHOWS PW AT MIAMI AT AROUND 2.25
INCHES. VERY IMPRESSIVE AND NEAR THE MAXIMUM RECORDED FOR THE
MONTH OF DECEMBER! PW AT BOTH NAPLES AND OKEECHOBEE WAS NEAR 1.9
INCHES. GIVEN THE IMPRESSIVE MOISTURE, THE ATMOSPHERE IS RIPE FOR
HEAVY RAINFALL PRODUCTION NEAR/IN ADVANCE OF THE FRONT OVER MIAMI-
DADE AND BROWARD. WAVES OF LOCALLY HEAVY RAINFALL ARE FORECAST TO
CONTINUE TO MOVE IN FROM THE SOUTHWEST TODAY ACROSS BROWARD/MIAMI-
DADE WITH LESS INTENSITY POINTS NORTH AND WEST. GIVEN RECENT HEAVY
RAINFALL IN SOME LOCALES OVER THE PAST 24 HOURS...ADDITIONAL
LOCALIZED HEAVY RAINFALL (3"+ POSSIBLE) COULD LEAD TO FLOODING AT
SOME LOCALES ACROSS THE MIAMI AND FORT LAUDERDALE METRO AREAS. AS
SUCH...CONTINUED THE FLOOD WATCH FOR BROWARD /MIAMI-DADE THROUGH
SAT MORNING. RAIN INTENSITY IS EXPECTED TO BE LESS POINTS NORTH
AND WEST...SO NO NEED TO EXPAND THE WATCH ELSEWHERE.
A FEW TSTORMS WILL CONTINUE...ESPECIALLY ACROSS THE ATLANTIC
WATERS, BUT POSSIBLE OVER LAND AS WELL TODAY. THE LACK THOUGH OF
APPRECIABLE INSTABILITY IS EXPECTED TO KEEP TSTORMS ORDINARY IN
NATURE WITH LIGHTNING/HEAVY RAIN THE THREATS.
AS WINDS TURN NORTHEAST BEHIND THE FRONT AND MOISTURE LAGS
BEHIND...CONVERGENCE ALONG THE EAST COAST IS FORECAST TO KEEP
SHOWERS GOING, ESPECIALLY ALONG THE COAST WHERE THE HEAVY RAIN
THREAT COULD CONTINUE THROUGH TONIGHT INTO EARLY SATURDAY.
THE FORECAST SUNDAY INTO MID WEEK FEATURES CONTINUED CHANCES OF
SHOWERS AS A NE WIND CONTINUES ALONG WITH SUFFICIENT MOISTURE TO
SUPPORT SHOWERS FOCUSED ALONG THE ATLANTIC COAST...WITH LESSER
CHANCES INLAND AND TO THE GULF COAST. BOTH GFS AND ECMWF SHOW
A SHORTWAVE MOVING ACROSS THE GULF DURING THE MIDDLE PART OF NEXT
WEEK WHICH COULD LEAD TO PERHAPS INCREASED SHOWER ACTIVITY THEN.
TEMPS CONTINUE ABOVE AVERAGE THROUGH NEXT WEEK...AND NO SIGNS OF
ANY SIGNIFICANT COOLING HERE. IN FACT, THE 540DM 1000-500 MB
THICKNESS LINE (OFTEN LOOKED AT FOR RAIN-SNOW LINE), RESIDES IN
CANADA TO THE NORTH OF MINNESOTA FOR MUCH OF NEXT WEEK...VERY
IMPRESSIVE FOR DECEMBER! #ELNINO /GREGORIA
MARINE...
COLD FRONT OVER THE LOCAL WATERS, STRETCHING EARLY THIS MORNING
FROM OFF THE BROWARD COUNTY COAST TO THE GULF WATERS OFF THE
MAINLAND MONROE COUNTY COAST, WILL SAG SLOWLY SOUTHEAST THROUGH
TONIGHT WITH NORTHEASTERLY WINDS INCREASING BEHIND THE FRONT. HIGH
PRESSURE BUILDING NORTH OF THE FRONT WILL RESULT IN A MODERATE TO
FRESH NORTHEAST WIND FLOW PREVAILING THROUGH THE WEEKEND.
A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR THE OFFSHORE GULF
WATERS EFFECTIVE THIS AFTERNOON THROUGH EARLY MONDAY.
A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR THE ATLANTIC WATERS
EFFECTIVE THIS EVENING THROUGH MONDAY MORNING AS GULF STREAM SEAS
BUILD TO 7+ FEET. /GREGORIA
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 74 82 76 83 / 40 60 50 50
FORT LAUDERDALE 69 80 72 81 / 50 60 50 50
MIAMI 71 81 73 82 / 50 60 50 50
NAPLES 66 84 68 84 / 30 40 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH THROUGH SATURDAY MORNING FOR FLZ071>074-172>174.
AM...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY
FOR AMZ650-651-670-671.
GM...SMALL CRAFT ADVISORY UNTIL 10 AM EST SUNDAY FOR GMZ676.
&&
$$
SHORT TERM...13/SI
LONG TERM....57/DG
AVIATION...23/SK
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1143 AM CST FRI DEC 4 2015
.UPDATE...
ISSUED AT 1047 AM CST FRI DEC 4 2015
High pressure still building into the region, with light winds
under the ridge. However, short term in eastern Illinois is
dominated by the persistent fog that is slow to burn off. Have
extended the fog advisory through midday. Sat imagery starting to
show some erosion on the western border of the fog bank. Some
minor updates to the hourlies based on the slower response of the
diurnal curve in the east as a result of the fog. Will be altering
some of the high temps as well. Update out momentarily.
&&
.SHORT TERM...(Today)
ISSUED AT 328 AM CST FRI DEC 4 2015
Persistent area of low clouds continues to blanket locations east of
the I-55 corridor early this morning. 09z/3am obs also show
widespread dense fog across this area, prompting the issuance of a
Dense Fog Advisory along/east of a Bloomington...to Decatur...to
Taylorville line. With high pressure centered over the Ohio River
Valley, very light S/SW low-level flow has been noted across the
northern half of the CWA: however, winds on the back side of the
high are beginning to take on a S/SE component across south-central
Illinois. IR satellite imagery is showing the low clouds/fog
inching westward just south of Taylorville, with the latest HRRR
suggesting this moisture might curl northward into the Springfield
and Lincoln areas in the next few hours. Will keep an eye on
satellite trends to see if this comes to pass and advisory needs to
be expanded westward to I-55. Due to the low sun angle and only
light low-level flow, fog will be slow to dissipate today. In fact,
HRRR suggests the far E/NE CWA near the Indiana border may remain
overcast for much of the day. Have extended the Dense Fog Advisory
until 17z/11am, but have kept skies mostly cloudy along and
northeast of a Champaign to Paris line until mid to late afternoon.
The evolution of the fog/clouds will have a big impact on high
temperatures. Based on expected trends, have kept readings coolest
in the lower 40s near Danville and Paris, with highs reaching the
upper 40s to around 50 elsewhere.
.LONG TERM...(Tonight through Thursday)
ISSUED AT 328 AM CST FRI DEC 4 2015
While the HRRR and Rapid Refresh have generally done a good job with
the low clouds/fog this morning, the NAM and especially the GFS have
not. In fact, GFS soundings indicate mostly clear skies and
unrestricted visbys today! As a result, am very skeptical about
forecast soundings from both models tonight. The GFS is again
clear: however, the NAM hints at low-level saturation and possible
fog. The high pressure center currently near Evansville, Indiana is
expected to shift into southern Ohio tonight, with the corresponding
ridge axis extending southwestward into the Ozarks. This will
result in the lightest winds across the E/SE CWA, with only a light
S/SW flow further north and west. Given persistent weather pattern,
have decided to include patchy fog mention along/southeast of a
Champaign to Taylorville line once again tonight. Once any morning
fog burns off, mostly sunny skies will prevail on Saturday. Thanks
to a good deal of sunshine and light southerly winds, afternoon high
temperatures will climb at least 10 degrees above normal for this
time of year into the lower 50s.
00z Dec 4 models are still having difficulty with the exact timing
and track of the next approaching short-wave early next week. The
ECMWF is about 6-12 hours faster with the wave than the GFS,
bringing it across central Illinois Sunday afternoon. Meanwhile,
the GFS is more amplified and slower, tracking the feature across
the area Sunday night into Monday. Run-to-run consistency remains
poor with both models, but will stick with the slightly more stable
GFS here. As synoptic lift increases ahead of the wave, clouds will
be on the increase on Sunday. The airmass will initially be quite
dry due to the presence of the strong surface ridge early in the
period, so moisture will remain limited. As a result, will only
feature a slight chance PoP for rain across the W/SW CWA Sunday
afternoon, then mainly across the S/SE Sunday night. These low
chance PoPs may need to be extended into Monday as well if the GFS
verifies. After that, models bring a series of ill-defined weak
short-waves across the CONUS through next week. Pinning down the
exact timing of these features within the zonal flow pattern will be
difficult. Given this fact and the overall lack of deep-layer
moisture, will continue with a mild and dry forecast through the
remainder of the extended.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
ISSUED AT 1141 AM CST FRI DEC 4 2015
Aviation concerns remain the same. Longevity of the VLIFR in the
east is finally abating at CMI and DEC to LIFR, and slow
improvement is expected in the next few hours. However, the longer
it lasts, the less of the llvl RH mixes out and the chances for
the fog returning in the morning goes up considerably. Have at
least started the trend for CMI to drop with a predominant, and
DEC with a tempo. Without the fog, SKC and light southerly flow
anticipated.
&&
.ILX Watches/Warnings/Advisories...
Dense Fog Advisory until 1 PM CST this afternoon for ILZ043>046-
053>057-061>063-066>068-071>073.
&&
$$
UPDATE...HJS
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...HJS
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1117 AM CST FRI DEC 4 2015
.UPDATE...
ISSUED AT 1047 AM CST FRI DEC 4 2015
High pressure still building into the region, with light winds
under the ridge. However, short term in eastern Illinois is
dominated by the persistent fog that is slow to burn off. Have
extended the fog advisory through midday. Sat imagery starting to
show some erosion on the western border of the fog bank. Some
minor updates to the hourlies based on the slower response of the
diurnal curve in the east as a result of the fog. Will be altering
some of the high temps as well. Update out momentarily.
&&
.SHORT TERM...(Today)
ISSUED AT 328 AM CST FRI DEC 4 2015
Persistent area of low clouds continues to blanket locations east of
the I-55 corridor early this morning. 09z/3am obs also show
widespread dense fog across this area, prompting the issuance of a
Dense Fog Advisory along/east of a Bloomington...to Decatur...to
Taylorville line. With high pressure centered over the Ohio River
Valley, very light S/SW low-level flow has been noted across the
northern half of the CWA: however, winds on the back side of the
high are beginning to take on a S/SE component across south-central
Illinois. IR satellite imagery is showing the low clouds/fog
inching westward just south of Taylorville, with the latest HRRR
suggesting this moisture might curl northward into the Springfield
and Lincoln areas in the next few hours. Will keep an eye on
satellite trends to see if this comes to pass and advisory needs to
be expanded westward to I-55. Due to the low sun angle and only
light low-level flow, fog will be slow to dissipate today. In fact,
HRRR suggests the far E/NE CWA near the Indiana border may remain
overcast for much of the day. Have extended the Dense Fog Advisory
until 17z/11am, but have kept skies mostly cloudy along and
northeast of a Champaign to Paris line until mid to late afternoon.
The evolution of the fog/clouds will have a big impact on high
temperatures. Based on expected trends, have kept readings coolest
in the lower 40s near Danville and Paris, with highs reaching the
upper 40s to around 50 elsewhere.
.LONG TERM...(Tonight through Thursday)
ISSUED AT 328 AM CST FRI DEC 4 2015
While the HRRR and Rapid Refresh have generally done a good job with
the low clouds/fog this morning, the NAM and especially the GFS have
not. In fact, GFS soundings indicate mostly clear skies and
unrestricted visbys today! As a result, am very skeptical about
forecast soundings from both models tonight. The GFS is again
clear: however, the NAM hints at low-level saturation and possible
fog. The high pressure center currently near Evansville, Indiana is
expected to shift into southern Ohio tonight, with the corresponding
ridge axis extending southwestward into the Ozarks. This will
result in the lightest winds across the E/SE CWA, with only a light
S/SW flow further north and west. Given persistent weather pattern,
have decided to include patchy fog mention along/southeast of a
Champaign to Taylorville line once again tonight. Once any morning
fog burns off, mostly sunny skies will prevail on Saturday. Thanks
to a good deal of sunshine and light southerly winds, afternoon high
temperatures will climb at least 10 degrees above normal for this
time of year into the lower 50s.
00z Dec 4 models are still having difficulty with the exact timing
and track of the next approaching short-wave early next week. The
ECMWF is about 6-12 hours faster with the wave than the GFS,
bringing it across central Illinois Sunday afternoon. Meanwhile,
the GFS is more amplified and slower, tracking the feature across
the area Sunday night into Monday. Run-to-run consistency remains
poor with both models, but will stick with the slightly more stable
GFS here. As synoptic lift increases ahead of the wave, clouds will
be on the increase on Sunday. The airmass will initially be quite
dry due to the presence of the strong surface ridge early in the
period, so moisture will remain limited. As a result, will only
feature a slight chance PoP for rain across the W/SW CWA Sunday
afternoon, then mainly across the S/SE Sunday night. These low
chance PoPs may need to be extended into Monday as well if the GFS
verifies. After that, models bring a series of ill-defined weak
short-waves across the CONUS through next week. Pinning down the
exact timing of these features within the zonal flow pattern will be
difficult. Given this fact and the overall lack of deep-layer
moisture, will continue with a mild and dry forecast through the
remainder of the extended.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 505 AM CST FRI DEC 4 2015
Variable conditions exist across the TAF forecast area with VLIFR
conditions prevailing just east of I-55, while MVFR and IFR
conditions are being reported west of the interstate. This will
continue through about 17z before we see a significant improvement
with confidence low for DEC and CMI where sounding data suggests
it may not be until 19z before vsbys and cigs improve. Even if we
do see cigs and vsbys come up across the east this afternoon, it
appears the setup will be about the same tonight as the surface
high and light wind fields prevail across the forecast area. Look
for light southerly winds today with speeds of 10 kts or less. The
winds will gradually back into a light southeast flow tonight.
&&
.ILX Watches/Warnings/Advisories...
Dense Fog Advisory until 1 PM CST this afternoon for ILZ043>046-
053>057-061>063-066>068-071>073.
&&
$$
UPDATE...HJS
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
557 PM EST FRI DEC 4 2015
.SYNOPSIS...
ISSUED AT 300 PM EST FRI DEC 4 2015
LOW CLOUDS AND FOG WILL QUICKLY FORM TONIGHT ACROSS MUCH OF THE
AREA AND PERSIST INTO AT LEAST SATURDAY MORNING. SOME OF THE FOG
COULD BE LOCALLY DENSE WITH VISIBILITIES LESS THAN ONE QUARTER
MILE...ESPECIALLY NORTHEAST OF ROUTE 30. LOWS WILL DROP INTO THE
UPPER 20S. CLOUDS AND FOG SHOULD SLOWLY LIFT THROUGH THE DAY
SATURDAY WITH HIGHS REACHING WELL INTO THE 40S.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 300 PM EST FRI DEC 4 2015
FAIRLY DRASTIC OVERALL TO GRIDS FOR TONIGHT INTO SATURDAY MORNING
TO REFLECT INCREASING CONCERNS FOR RAPID REDEVELOPMENT OF WIDESPREAD
STRATUS AND FOG (POSSIBLY DENSE) ACROSS THE AREA. VIS SAT AND
OBSERVATIONS SHOW SCOURING OUT OF STRATUS DECK CONTINUES...BUT WILL
LIKELY REACH THE END OF THIS OCCURRING IN THE NEXT HOUR OR 2 AS PEAK
HEATING AND MIXING DIMINISHES. DESPITE THE CLEARING A SLOW INCREASE
IN LOW LEVEL MSTR COMBINED WITH LIGHT WINDS AND MOSTLY CLEAR TO
CLEAR SKIES WILL SET THE STAGE FOR RAPID DEVELOPMENT OF STRATUS
ACROSS THE AREA THIS EVENING. HRRR HAS BEEN HANDLING OVERALL SETUP
QUITE WELL BOTH LAST NIGHT AND TODAY AND QUICKLY BRINGS STRATUS AND
DENSE FOG BACK IN BETWEEN 3 AND 6Z SAT. GRIDS NOW REFLECT A RETURN
TO CLOUDY SKIES BY LATE EVENING WITH PATCHY FOG
INITIALLY...EVENTUALLY GOING TO AREAS OF FOG. WHERE FULL CLEARING
HAS TAKEN PLACE...A MENTION OF PATCHY DENSE FREEZING FOG HAS BEEN
ADDED AS TEMPS DROP BELOW FREEZING ACROSS THE AREA AND GREATER
CONCENTRATION OF WATER DROPLETS MAY GIVE A LIGHT GLAZE ON ELEVATED
SURFACES. FOR NOW WILL HOLD OFF ON ANY HEADLINES AND DEFER TO EVE
SHIFT TO MONITOR TRENDS AS COULD END UP MAINLY THE STRATUS ISSUE AND
VSBYS BEHAVE THEMSELVES.
NEXT CHALLENGE WILL BE IF THE STRATUS/FOG CAN LIFT DURING THE DAY
SATURDAY AS INVERSION REMAINS IN PLACE. CLEARING MAY BE HIGHLY
DEPENDENT ON ACTUAL DEPTH OF THE STRATUS DECK. TODAY IT WAS ON
THE THINNER SIDE AND ALLOWED AT LEAST SOME MIXING. THIS MAY NOT BE
THE CASE TOMORROW AS RIDGE AXIS SHIFTS OVERHEAD AND POTENTIALLY
TRAPS THE LOW CLOUDS AND SOME FOG THROUGH THE DAY. FOR NOW WILL
KEEP WITH AT LEAST SOME CLEARING...BUT EXTENSIVE UPDATE CHANGES
MAY BE NEEDED IN LATER FORECASTS. WILL GO WITH GENERAL PERSISTENCE
ON TEMPS AS WELL WITH BUST POTENTIAL MODERATE TO HIGH.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 300 PM EST FRI DEC 4 2015
LONG TERM PERIOD BEGINS QUIETLY...WITH LARGE SCALE RIDGE AXIS
CENTERED EAST OF THE REGION SUNDAY AND UPPER TROF/CUTOFF LOW
APPROACHING THE REGION FROM THE WEST. CONTINUED WITH A DRY FORECAST
OF 14 POPS OR LESS SUNDAY NIGHT/EARLY MONDAY AS THIS SYSTEM PASSES
THROUGH THE REGION...WITH A BULK OF THE FORCING AND MOISTURE
REMAINING SOUTH OF THE REGION.
A ZONAL FLOW REGIME TAKES HOLD ACROSS THE CONUS THROUGH MUCH OF NEXT
WEEK. THE MAIN FORECAST CHALLENGE WILL BE EMBEDDED SHORTWAVES
TRACKING THROUGH THIS ZONAL FLOW REGIME AND POTENTIAL PRECIPITATION
FOR THE FORECAST AREA. LONG TERM MODEL SOLUTIONS DIFFER WITH THE
HANDLING OF THESE SYSTEMS. WENT WITH A CONSENSUS BLEND APPROACH
WHICH YIELDED SLIGHT CHANCE POPS WEDNESDAY THROUGH THE END OF THE
PERIOD. HONED THESE POPS DOWN TO WEDNESDAY AND WED NIGHT
TIMEFRAME...WHICH QUICK MOVING WAVE TRACKS SOMEWHERE THROUGH THE
REGION...BUT KEPT POPS LESS THAN 20 PERCENT. WENT WITH A CONTINUED
DRY FORECAST THURSDAY AND THURSDAY NIGHT...BUT KEPT THE CONSENSUS
BLEND SOLUTION FOR FRIDAY WITH VERY LOW CHANCE POPS. TOWARD THE END
OF NEXT WEEK...THE OVERALL PATTERN BECOMES MORE AMPLIFIED AS STRONG
EPAC UPPER JET BUCKLES...WITH DEEPER TROUGHING OVER THE WRN CONUS
AND DOWNSTREAM ERN CONUS RIDGING. WHEN THIS ENERGY EJECTS THROUGH
THE REGION SOMETIME TOWARDS THE END OF THE WEEK/NEXT WEEKEND...THIS
WOULD INCREASE PRECIPITATION CHANCES GREATLY. HOWEVER LONG RANGE
MODELS DIFFER GREATLY WITH TIMING/EVOLUTION OF THIS SYSTEM...WHICH
COULD BRING A DECENT RAINFALL TO THE AREA DEPENDING ON THE
EVOLUTION. FOR NOW...WITH STICK WITH THE LOW CHANCE POPS FOR
FRIDAY...BUT THIS WILL BE THE TIME PERIOD TO WATCH FOR THE NEXT
CHANCE OF A DECENT RAINFALL FOR THE REGION.
OTHERWISE...TEMPS THROUGH THE PERIOD WILL BE MILD FOR EARLY/MID
DECEMBER STANDARDS...WITH HIGHS IN THE LOW TO MID 40S SUNDAY THROUGH
TUESDAY...AND MID TO UPPER 40S AND POSSIBLE 50S LATER IN THE PERIOD.
LOW TEMPS THROUGH THE PERIOD WILL START OUT AT OR BELOW FREEZING SAT
NIGHT AND SUN NIGHT...THEN WARMING THROUGH THE 30S EACH NIGHT
THROUGH THE END OF THE PERIOD. THIS WOULD YIELD POTENTIAL AVERAGE
TEMPS NEARLY 10 DEGREES ABOVE NORMAL BY THE END OF THE FORECAST
PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 557 PM EST FRI DEC 4 2015
WIDESPREAD IFR CONDS XPCD AGAIN OVERNIGHT INTO SAT AM AS STAGNANT
SFC RIDGE PERSISTS THROUGH THE OH VALLEY. MOIST BNDRY LYR REMAINS
TRAPPED BENEATH LL THERMAL INVERSION. PRIOR WK DIURNALLY PEAKED
MIXING HAS DIMINISHED W/SUNDOWN AND ALREADY SEEING A INCREASING
NEWD EXPANSION OF EXISTING WEDGE CNTRD ACRS WRN IN. BOTH NR AND
SHRT TERM GUIDANCE OUTSIDE HRRR SOLUTION WORTHLESS W/CURRENT AND
PROGGED SCENARIO GOING FWD THUS SIDED SIG GRID UPDATE TWD HRRR.
NEWD PROGRESSION OF SFC RIDGE CNTR TWD WRN LK ERIE SAT AM ALG
W/INCREASING SWRLY FLW ALG WRN FLANK DOES PORTENT BTR MIXING
POTENTIAL TWD ERLY AFTN AND WILL FOLLOW OBSVD PERSISTENCE OB
TRENDS FM TDA IN 00Z TERMINAL FCSTS.
OTRWS HYDRO LAPSE RATES SUGGEST FOG WILL BECOME MORE OF AN ISSUE
ESP TWD SUNRISE W/A PD OF LIFR VSBYS PSBL.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...FISHER
SHORT TERM...FISHER
LONG TERM...NG
AVIATION...T
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
304 PM EST FRI DEC 4 2015
.SYNOPSIS...
ISSUED AT 300 PM EST FRI DEC 4 2015
LOW CLOUDS AND FOG WILL QUICKLY FORM TONIGHT ACROSS MUCH OF THE
AREA AND PERSIST INTO AT LEAST SATURDAY MORNING. SOME OF THE FOG
COULD BE LOCALLY DENSE WITH VISIBILITIES LESS THAN ONE QUARTER
MILE...ESPECIALLY NORTHEAST OF ROUTE 30. LOWS WILL DROP INTO THE
UPPER 20S. CLOUDS AND FOG SHOULD SLOWLY LIFT THROUGH THE DAY
SATURDAY WITH HIGHS REACHING WELL INTO THE 40S.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 300 PM EST FRI DEC 4 2015
FAIRLY DRASTIC OVERALL TO GRIDS FOR TONIGHT INTO SATURDAY MORNING
TO REFLECT INCREASING CONCERNS FOR RAPID REDEVELOPMENT OF WIDESPREAD
STRATUS AND FOG (POSSIBLY DENSE) ACROSS THE AREA. VIS SAT AND
OBSERVATIONS SHOW SCOURING OUT OF STRATUS DECK CONTINUES...BUT WILL
LIKELY REACH THE END OF THIS OCCURRING IN THE NEXT HOUR OR 2 AS PEAK
HEATING AND MIXING DIMINISHES. DESPITE THE CLEARING A SLOW INCREASE
IN LOW LEVEL MSTR COMBINED WITH LIGHT WINDS AND MOSTLY CLEAR TO
CLEAR SKIES WILL SET THE STAGE FOR RAPID DEVELOPMENT OF STRATUS
ACROSS THE AREA THIS EVENING. HRRR HAS BEEN HANDLING OVERALL SETUP
QUITE WELL BOTH LAST NIGHT AND TODAY AND QUICKLY BRINGS STRATUS AND
DENSE FOG BACK IN BETWEEN 3 AND 6Z SAT. GRIDS NOW REFLECT A RETURN
TO CLOUDY SKIES BY LATE EVENING WITH PATCHY FOG
INITIALLY...EVENTUALLY GOING TO AREAS OF FOG. WHERE FULL CLEARING
HAS TAKEN PLACE...A MENTION OF PATCHY DENSE FREEZING FOG HAS BEEN
ADDED AS TEMPS DROP BELOW FREEZING ACROSS THE AREA AND GREATER
CONCENTRATION OF WATER DROPLETS MAY GIVE A LIGHT GLAZE ON ELEVATED
SURFACES. FOR NOW WILL HOLD OFF ON ANY HEADLINES AND DEFER TO EVE
SHIFT TO MONITOR TRENDS AS COULD END UP MAINLY THE STRATUS ISSUE AND
VSBYS BEHAVE THEMSELVES.
NEXT CHALLENGE WILL BE IF THE STRATUS/FOG CAN LIFT DURING THE DAY
SATURDAY AS INVERSION REMAINS IN PLACE. CLEARING MAY BE HIGHLY
DEPENDENT ON ACTUAL DEPTH OF THE STRATUS DECK. TODAY IT WAS ON
THE THINNER SIDE AND ALLOWED AT LEAST SOME MIXING. THIS MAY NOT BE
THE CASE TOMORROW AS RIDGE AXIS SHIFTS OVERHEAD AND POTENTIALLY
TRAPS THE LOW CLOUDS AND SOME FOG THROUGH THE DAY. FOR NOW WILL
KEEP WITH AT LEAST SOME CLEARING...BUT EXTENSIVE UPDATE CHANGES
MAY BE NEEDED IN LATER FORECASTS. WILL GO WITH GENERAL PERSISTENCE
ON TEMPS AS WELL WITH BUST POTENTIAL MODERATE TO HIGH.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 300 PM EST FRI DEC 4 2015
LONG TERM PERIOD BEGINS QUIETLY...WITH LARGE SCALE RIDGE AXIS
CENTERED EAST OF THE REGION SUNDAY AND UPPER TROF/CUTOFF LOW
APPROACHING THE REGION FROM THE WEST. CONTINUED WITH A DRY FORECAST
OF 14 POPS OR LESS SUNDAY NIGHT/EARLY MONDAY AS THIS SYSTEM PASSES
THROUGH THE REGION...WITH A BULK OF THE FORCING AND MOISTURE
REMAINING SOUTH OF THE REGION.
A ZONAL FLOW REGIME TAKES HOLD ACROSS THE CONUS THROUGH MUCH OF NEXT
WEEK. THE MAIN FORECAST CHALLENGE WILL BE EMBEDDED SHORTWAVES
TRACKING THROUGH THIS ZONAL FLOW REGIME AND POTENTIAL PRECIPITATION
FOR THE FORECAST AREA. LONG TERM MODEL SOLUTIONS DIFFER WITH THE
HANDLING OF THESE SYSTEMS. WENT WITH A CONSENSUS BLEND APPROACH
WHICH YIELDED SLIGHT CHANCE POPS WEDNESDAY THROUGH THE END OF THE
PERIOD. HONED THESE POPS DOWN TO WEDNESDAY AND WED NIGHT
TIMEFRAME...WHICH QUICK MOVING WAVE TRACKS SOMEWHERE THROUGH THE
REGION...BUT KEPT POPS LESS THAN 20 PERCENT. WENT WITH A CONTINUED
DRY FORECAST THURSDAY AND THURSDAY NIGHT...BUT KEPT THE CONSENSUS
BLEND SOLUTION FOR FRIDAY WITH VERY LOW CHANCE POPS. TOWARD THE END
OF NEXT WEEK...THE OVERALL PATTERN BECOMES MORE AMPLIFIED AS STRONG
EPAC UPPER JET BUCKLES...WITH DEEPER TROUGHING OVER THE WRN CONUS
AND DOWNSTREAM ERN CONUS RIDGING. WHEN THIS ENERGY EJECTS THROUGH
THE REGION SOMETIME TOWARDS THE END OF THE WEEK/NEXT WEEKEND...THIS
WOULD INCREASE PRECIPITATION CHANCES GREATLY. HOWEVER LONG RANGE
MODELS DIFFER GREATLY WITH TIMING/EVOLUTION OF THIS SYSTEM...WHICH
COULD BRING A DECENT RAINFALL TO THE AREA DEPENDING ON THE
EVOLUTION. FOR NOW...WITH STICK WITH THE LOW CHANCE POPS FOR
FRIDAY...BUT THIS WILL BE THE TIME PERIOD TO WATCH FOR THE NEXT
CHANCE OF A DECENT RAINFALL FOR THE REGION.
OTHERWISE...TEMPS THROUGH THE PERIOD WILL BE MILD FOR EARLY/MID
DECEMBER STANDARDS...WITH HIGHS IN THE LOW TO MID 40S SUNDAY THROUGH
TUESDAY...AND MID TO UPPER 40S AND POSSIBLE 50S LATER IN THE PERIOD.
LOW TEMPS THROUGH THE PERIOD WILL START OUT AT OR BELOW FREEZING SAT
NIGHT AND SUN NIGHT...THEN WARMING THROUGH THE 30S EACH NIGHT
THROUGH THE END OF THE PERIOD. THIS WOULD YIELD POTENTIAL AVERAGE
TEMPS NEARLY 10 DEGREES ABOVE NORMAL BY THE END OF THE FORECAST
PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1259 PM EST FRI DEC 4 2015
VFR CONDITIONS HAVE ARRIVED AT KSBN AND SHOULD PERSIST THROUGH AT
LEAST 6Z. CLOUD BASES WERE SLOWLY RISING AT KFWA WITH FULL MIXING
OUT OCCURRING BETWEEN 19 AND 20Z. INCREASING CONCERN FOR FOG
DEVELOPMENT...ESPECIALLY KSBN CLOSER TO SAT MORNING AS MOIST
BOUNDARY LAYER WILL BE IN PLACE WITH IDEAL COOLING SETUP TO ALLOW
FOR PATCHY GROUND FOG. HAVE INTRODUCED A TEMPO GROUP TO KSBN 10 TO
14Z OF MVFR/IFR VSBYS WITH UPPER END MVFR AT KFWA. FURTHER CHANGES
WILL LIKELY BE NEEDED FOR 00Z TAFS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...FISHER
SHORT TERM...FISHER
LONG TERM...NG
AVIATION...FISHER
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
National Weather Service Paducah KY
220 PM CST FRI DEC 4 2015
.SHORT TERM...(This evening through Sunday)
Issued at 206 PM CST FRI DEC 4 2015
Once again today, there is a strong subsidence inversion just off
the surface, keeping this morning`s fog/low stratus trapped
beneath 1000 FT AGL. This area had shriveled northward by mid
morning, where it has remained nearly stationary thru the
day...just barely beyond our northern CWA border. Differential
heating right along its southern extent has eaten away at it
gradually in the last hour or two...and may preclude its sag back
into the FA tonight, as temps even on our northern periphery have
bounded upwards closer to the rest of the FA. Even so, that area
will need to be closely monitored, in case our northern tier
counties end up having it develop again.
The center of the surface high shifts eastward tonight and light
selys at and just off the surface will hopefully preclude that
from happening. Still anticipate another cool night, with lows
again at or just below climo (u20s/nr 30).
More robust warm air advection will begin tmrw, and continue thru
the weekend. It will take awhile to warm (and moisten) the dry
atmos column, so most of the weekend should remain dry, as temps
rebound into/thru the 50s/30s for highs/lows.
.LONG TERM...(Sunday night through Friday)
Issued at 206 PM CST FRI DEC 4 2015
A minor mid level shrtwv/closed low is progged by the models to be
moving through the PAH forecast area Sun night. Moist return flow
will be very limited with this system, but there will be at least
the passage of a sfc cold front with it, triggering light amounts of
rain mainly east of the MS river. The probability for actual
measurable pcpn remains quite low. The disturbance should be out of
our region after 12Z Mon.
The Pacific train of low-amplitude shrtwvs will apparently continue
through most of the week. Another impulse and sfc front may affect
the region Wed, and again on Fri. The timing of these impulses is
quite variable among the med range models, especially for day 6 and
7. For now, we will go with a forecast of a couple of low PoP, low
QFP rain events, with partly cloudy and relatively mild conditions
in between, especially toward Day 7. In fact, just beyond Day 7, the
ECENES/GEFS are beginning to suggest a change to the recent pattern
aloft, to a longwave trof west/ridge east, which would promote
warmer swrly flow aloft for our region.
&&
.AVIATION...
Issued at 206 PM CST FRI DEC 4 2015
Strong subsidence inversion precludes parcels uvm above 1000 FT
AGL, so SKC abounds. Nearby, do see trapped morning fogs/low
stratus beneath said inversion, and will have to watch this area
closely in case it sags southward down the Wabash valley and
impacts KEVV (or KOWB). For now, will just hit a little MVFR late
night fog all terminals as depression temps close. Otherwise
little to note in light wind regime with surface high slowly
nudging to the east with time.
&&
.PAH Watches/Warnings/Advisories...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
[top]
Area Forecast Discussion
National Weather Service Louisville KY
254 PM EST FRI DEC 4 2015
.SHORT TERM (Now through Sunday)...
Issued at 245 PM EST Fri Dec 4 2015
Main short-term challenge is the extent and impact of potential
freezing fog late tonight into Sat morning. This morning saw quite a
bit of fog, with most of the valleys finally breaking out just
before midday while a more extensive area of stratus/fog held on in
our northernmost counties in southern Indiana.
Thinking is that we will see a repeat of the valley fog late
tonight, but a few factors weigh against any expansion onto the
higher/flatter terrain even though winds will be light and RH fields
could support a "sunrise surprise." Strong surface high draped
across northern Kentucky and southern Indiana/Ohio will start
retreating to the east, establishing a light easterly low-level
flow. This carries a slight downslope component, and should limit
fog to just the more sheltered areas. Also we are finally starting
to see some thin spots in the stratus over central Indiana and
western Ohio, and guidance suggests these clouds will dissipate in
the evening when the easterly flow sets up. Therefore will limit the
mention of fog to the valleys, but where it does occur freezing fog
will be a concern. Will highlight that in the HWO, and let later
shifts hone in on where the real problem areas will be.
Once the valley fog dissipates Sat morning, it looks like an
unusually pleasant December weekend with seasonable temps and quite
a bit of sunshine. Temps should run just above climo by day and just
below by night. Max temp forecasts favored the GFS MOS, with
Saturday just a bit milder than Sunday out of respect for the cloud
shield that will arrive Sunday afternoon ahead of the next system.
Sat night min temp forecast is below guidance, as it still looks
favorable for radiational cooling, and the long night should still
allow a sharp and shallow inversion to develop underneath the weak
return flow.
.LONG TERM (Sunday night through Friday)...
Issued at 245 PM EST Fri Dec 4 2015
Progressive pattern will remain in place for much of next week, with
a series of closed upper lows rolling through. First system comes
through Sunday night and Monday, and without any opportunity for the
Gulf to open up, it looks like a low-POP, low-QPF scenario. Not much
change to the going forecast there, and daytime temps are knocked
back a couple degrees to climo.
Flat pattern Monday night through Tuesday night will amplify again
on Wednesday, with the next upper low closing off as it swings
through the Ohio Valley. This system draws enough moisture northward
to support low chance POPs. Will keep QPF low for now, but the ECMWF
is the more bullish of the models here and could provide a decent
shot of rain if it verifies.
By Friday yet another upper trof will be headed our way, this time a
southern stream system lifting out of the Desert Southwest. Not
confident enough in the timing to go any higher than chance POPs for
Friday, but when this system does come through, higher POPs and
higher QPF will be warranted as it could start to take on enough of
a negative tilt to tap into better moisture. Still expect the main
impact of this system to be beyond the scope of this 7-day forecast.
&&
.AVIATION (18Z TAF Update)...
Updated at 1210 PM EST Fri Dec 4 2015
Tougher forecast for tonight than would appear given that 99% of the
troposphere looks dry. Cigs over a lot of Indiana are in the
LIFR/VLIFR range still this morning. HRRR did a better job with
these clouds overnight and it now is calling for a southward
expansion of those clouds in patches over central Kentucky. The
patchy nature makes it hard to go all out over the terminals
tonight. For now will go with few-sct very low deck and some
reduction in vsby toward daybreak, but cannot rule out much worse
conditions. Will amend as more hi-res near-term guidance comes in.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Short Term........RAS
Long Term.........RAS
Aviation..........RJS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1220 PM EST FRI DEC 4 2015
.UPDATE...
ISSUED AT 1132 AM EST FRI DEC 4 2015
VIS SAT NOW SHOWING THAT MOST OF THE RIVER VALLEY FOG HAS CLEARED
OUT THIS LATE MORNING HOUR. THEREFORE WILL UPDATE THE
NDFD GRIDS...ZFP...AND HWO TO REFLECT THIS THOUGHT. OTHERWISE
JUST SOME MINOR TWEAKS TO LATEST OBS AND TRENDS.
UPDATE ISSUED AT 958 AM EST FRI DEC 4 2015
VIS SAT CONTINUES TO SHOW RIVER VALLEY FOG...WHICH GIVEN THE TEMPS
THIS MORNING WILL LIKELY BE FREEZING FOG. NO ISSUES ROAD WISE ARE
EXPECTED THIS MORNING. THIS VALLEY FOG WILL CONTINUE TO DISSIPATE
THROUGH THE MORNING HOURS. UPDATED GRIDS TO REFLECT VALLEY FOG
LOCATIONS...OTHERWISE NOT MAJOR CHANGES NEEDED THIS UPDATE. DID
OPT TO UPDATE THE TEMP...DEWS... AND WINDS WITH LATEST OBS AND
TRENDS. GRIDS HAVE BEEN SENT TO NDFD.
UPDATE ISSUED AT 727 AM EST FRI DEC 4 2015
SINCE ALL TEMPERATURES ACROSS THE REGION ARE BELOW FREEZING...IT
IS LIKELY THAT WHATEVER PATCHY FOG HAS DEVELOPED ACROSS THE REGION
IS OF THE FREEZING VARIETY. AS SUCH...CHANGED WEATHER GRIDS FOR
THE NEXT COUPLE HOURS TO REFLECT PATCHY FREEZING FOG INSTEAD.
ALSO HIGHLIGHTED POTENTIAL IMPACTS IN THE HWO. HOWEVER...GIVEN THE
PATCHY NATURE OF THE FOG AND WITH LITTLE TO NO IMPACTS REPORTED
THUS FAR...DID NOT ISSUE ANY FURTHER PRODUCTS. MOST REPORTS THIS
MORNING HAVE BEEN FOR FROST RATHER THAN FOG. REGARDLESS...ANY
REMAINING FOG SHOULD BURN OFF OVER THE NEXT HOUR OR TWO AS WE
CONTINUE TO WARM UP. LOADED IN THE LATEST OBSERVATIONS TO MAKE
SURE THE NEAR TERM FORECAST WAS WELL ON TRACK WITH THE CURRENT
CONDITIONS. A NEW FORECAST PACKAGE WAS SENT OUT TO REFLECT THE
CHANGES IN FOG WORDING. ALL GRIDS WERE PUBLISHED AND SENT TO
NDFD/WEB.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 242 AM EST FRI DEC 4 2015
HIGH PRESSURE IS CURRENTLY DIRECTLY OVERHEAD THE STATE OF KENTUCKY
AS OF 7Z. THIS IS PROVIDING LIGHT WINDS AND STRONG SUBSIDENCE DURING
THE OVERNIGHT HOURS. WENT AHEAD AND LOWERED SOME OF THE DEEPER
VALLEY LOCATIONS LOW TEMPERATURES FOR EARLY THIS MORNING GIVEN THE
CURRENT OBSERVATIONS.
OTHERWISE...EXPECT QUIET AND CLEAR CONDITIONS THROUGH THE DURATION
OF THE SHORT TERM PERIOD AS THE HIGH PRESSURE REMAINS OVERHEAD.
AFTERNOON TEMPERATURES WILL CONTINUE TO SHOW AN INCREASING
TREND...WITH HIGHS TODAY TOPPING OUT AROUND THE 50 DEGREE
MARK...THEN CLIMBING TO THE MID TO UPPER 50S BY TOMORROW. STRONG
SUBSIDENCE AND MAXIMUM RADIATIONAL COOLING OVERNIGHT TONIGHT WILL
PROMOTE ANOTHER RIDGE VALLEY SPLIT AND SIGNIFICANT DIURNAL
DROPS...WITH UPPER 20S TO AROUND 30 EXPECTED ON THE RIDGES FOR
LOWS...AND LOW TO MID 20S IN THE VALLEYS.
THE ONE CONCERN DURING THIS FORECAST PERIOD WILL BE THE AMOUNT OF
DRY AIR BEING USHERED INTO THE REGION UNDER THE INFLUENCE OF THIS
HIGH PRESSURE SYSTEM. THIS WILL CREATE LOW DEW POINTS AND LOW RH
SITUATIONS BOTH THIS AFTERNOON...AND EVEN MORE SO SATURDAY
AFTERNOON. LUCKILY...WINDS WILL BE LIGHT AND PREVIOUS DAYS RAINS
WILL HELP TO MITIGATE SOME OF THE FIRE CONCERNS...BUT THIS WILL
CONTINUE TO BE SOMETHING TO MONITOR THROUGH THE UPCOMING WEEKEND.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 458 AM EST FRI DEC 4 2015
THE EXTENDED PERIOD WILL START OUT DRY AND PLEASANT...WITH ABOVE
NORMAL TEMPERATURES EXPECTED DURING THE DAY ON SUNDAY.
HOWEVER...CONDITIONS WILL START OUT QUITE COLD ACROSS THE AREA ON
SUNDAY MORNING...WITH LOWS DROPPING INTO THE LOW TO MID 20S IN OUR
VALLEYS...WHILE THE SURROUNDING RIDGES ONLY FALL INTO THE LOW TO
MID 30S. THE WEATHER IS EXPECTED TO REMAIN DRY THROUGH EARLY
MONDAY EVENING. AFTER MONDAY EVENING...HOWEVER...THE MODEL DATA
BEGINS TO DIVERGE...LEAVING US WITH AN UNCERTAIN FORECAST FROM
MONDAY NIGHT ONWARD. FOR NOW...WITH THE MODELS SHOWING A SERIES OF
FAST MOVING SHORT WAVES EJECTING OUT OF THE PLAINS AND ACROSS THE
EASTERN THIRD OF THE CONUS...DECIDED TO GO WITH LOW PRECIPITATION
CHANCES SUNDAY NIGHT THROUGH LATE MONDAY NIGHT. AFTER ANOTHER
POSSIBLE DRY PERIOD TUESDAY AND TUESDAY NIGHT...INTRODUCED MORE
RAIN CHANCES WEDNESDAY THROUGH THURSDAY...AS THE ECMWF MODEL TRIES
TO BRING A FAIRLY WELL DEVELOPED AREA OF LOW PRESSURE OUT OF THE
PLAINS AND ACROSS THE UPPER MISSISSIPPI VALLEY AND GREAT LAKES
REGIONS. THE SURFACE FRONT THAT WOULD BE ASSOCIATED WITH THIS
UPPER LOW WOULD WHAT WOULD BRING RAINFALL TO OUR AREA.
HOWEVER...THE GFS MODEL IS DRY FOR THURSDAY...WHEN THE ECMWF HAS
AN AREA OF RAINFALL AFFECTING THE AREA. WITH THAT IN MIND...WENT
WITH ONLY A SLIGHT CHANCE OF RAIN ACROSS EASTERN KENTUCKY FOR THE
WEDNESDAY THURSDAY TIME FRAME.
TEMPERATURES ACROSS THE AREA ARE EXPECTED TO BE GENERALLY ABOVE
NORMAL THROUGH OUT THE PERIOD...WITH DAY TIME HIGHS IN THE MID TO
UPPER 50S AND OVERNIGHT LOWS IN THE MID TO UPPER 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1220 PM EST FRI DEC 4 2015
HIGH PRESSURE IS LEADING TO VFR CONDITIONS ACROSS THE REGION THIS
AFTERNOON. THIS IS EXPECTED TO BE THE STORY FOR THE TAF PERIOD IN
GENERAL. THIS MORNING WE HAD A FEW INSTANCES OF MAINLY RIVER
VALLEY FREEZING FOG...SOUNDINGS DO SUGGEST A SOME LOW LEVEL
MOISTURE ON SATURDAY MORNING. RIGHT NOW NOT CONFIDENT THIS WILL
MAKE IT INTO ANY OF THE TAF SITES...SO HAVE OPTED NOT TO INCLUDE
IN THIS TAF CYCLE. THIS SURFACE HIGH PRESSURE IS ALSO INTRODUCING
LIGHT AND VARIABLE WINDS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...JMW
LONG TERM...AR
AVIATION...DJ
Area Forecast Discussion
National Weather Service Louisville KY
1209 PM EST FRI DEC 4 2015
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1055 AM Fri Dec 4 2015
Fog is finally dissipating in a lot of the valleys, but the more
extensive area of fog/stratus over Indiana is going nowhere fast.
Have updated products to remove the fog mention, except over our
northernmost counties in southern Indiana, where the clouds/fog will
hang on for much of the afternoon. Temps are just warm enough that
in daylight conditions, freezing fog should not be as much of an
issue as it had been earlier. Therefore will just keep it plain old
fog. Have clipped max temps by several degrees where the clouds and
fog remain, but if it`s persistent enough, even the mid 40s in the
revised forecast may be too generous. Still on track for around 50
elsewhere.
Issued at 925 AM Fri Dec 4 2015
Patchy freezing fog is mostly dissipating based on latest METARs and
area webcams. Still seeing some of the deeper river valleys pretty
well socked in, so will take a bit slower approach to removing the
early fog wording from the ZFP. A more extensive area of fog/stratus
sits over Indiana just north of our CWA boundary, and I have little
confidence that it will go anywhere given poor mixing under a 1037mb
high pressure, and low December sun angle. That said, the current
forecast should be pretty well on track, so will just refresh to
pull the fog wording as the valleys finally start to mix a bit, and
will keep an eye on whether the stratus deck tries to creep into our
Indiana counties.
.SHORT TERM (Now through Saturday)...
Issued at 300 AM EST Fri Dec 4 2015
In the near term, high pressure will drift overhead early this
morning and then move slowly eastward during the day today. IR
satellite imagery reveals clear skies across the region. A decent
ridge/valley decoupling has taken place with the cooler valleys
presently sitting in the mid 20s with upper 20s to around 30
elsewhere. Dry air is abundant aloft across the region. However,
we do have some low-level moisture down near the surface which may
result in some areas of freezing fog this morning. The best chances
for the fog look to be across our southern Indiana counties and in
the KY river valley region of central KY. Temperatures may cool a
few more degrees before sunrise with most locations seeing readings
in the low-mid 20s in the valleys and in the mid-upper 20s elsewhere.
For Today through Saturday, quiet weather is expected as high
pressure will continue to dominance our weather pattern. Highs this
afternoon will warm into the upper 40s to around 50 in the north
with lower 50s likely across southern KY. Another cool night looks
likely tonight with lows in the valleys cooling into the lower-mid
20s with mid-upper 20s elsewhere. We will pick up a bit more
southerly flow on Saturday with mostly sunny skies. Temperatures
look to warm into the lower 50s in the north with low-mid 50s across
the south.
.LONG TERM (Saturday Night through Thursday)...
Issued at 323 AM EST Fri Dec 4 2015
In the long term period, a progressive flow will remain in place
aloft with a series of compact upper level lows rolling from east to
west across the CONUS. The first of these will transverse our
region late Sunday and into the day on Monday. Moisture is not all
that plentiful with the system as return flow from the Gulf will not
have sufficient time to moisten up the column. However, model time-
height cross sections do suggest plenty of mid-high level cloud
cover to push through with this system. Ascent is not overly
strong, but forcing with the upper low (mainly due to steep lapse
rates) look to be enough to continue low chance PoPs in the Sunday
night/Monday time frame.
The upper flow will then flatten back out by Tuesday, only to re-
amplify as the next upper level low crosses the region Wednesday
night into Thursday as it ejects from the northern Plains. Again,
large scale ascent with this system is not overly impressive, but
enough moisture and lift look available to warrant low chance PoPs
in the Wed night/Thursday time frame...despite the blended guidance
being a little more optimistic on dry conditions.
Temperatures through the period look to run a little above seasonal
normals. Typical early December highs average in the upper 40s. The
latest guidance suggests daily highs in the lower to middle 50s with
overnight lows in the mid-upper 30s. The warmest day looks to be
Thursday where some upper 50s across the south will be possible.
Overall, not much in the way of change from the previous forecast.
Looking further out, a more active weather pattern looks to take
shape as we head into late next week and into the mid part of
December. Latest teleconnection pattern suggest a
+AO/+NAO/+PNA/+EPO pattern in place by late next week. These
indices would support the series of rolling upper level lows across
the CONUS. However, as we head down the road, the models suggest a
downward trend in all the indices as we head toward mid-month. As
this downward trend occurs, we`re likely to see an active weather
pattern set up across the central US and eventually into the Ohio
Valley.
Initially, we`ll be on the warm side of the pattern with the threat
of additional heavy rainfall and milder than normal temperatures. As
the indices slide toward the neutral/negative range, we`ll
gradually see the sensible weather catch up with a more seasonal
cold pattern emerging after mid-month. It should be noted that the
long term models have struggled with timing of the downtrend in the
teleconnection indices. Past verification shows that they tend to
drop the indices too quick...so it would not be surprising to see
the eventual return to seasonal cold to be delayed slightly in later
forecasts.
&&
.AVIATION (18Z TAF Update)...
Updated at 1210 PM EST Fri Dec 4 2015
Tougher forecast for tonight than would appear given that 99% of the
troposphere looks dry. Cigs over a lot of Indiana are in the
LIFR/VLIFR range still this morning. HRRR did a better job with
these clouds overnight and it now is calling for a southward
expansion of those clouds in patches over central Kentucky. The
patchy nature makes it hard to go all out over the terminals
tonight. For now will go with few-sct very low deck and some
reduction in vsby toward daybreak, but cannot rule out much worse
conditions. Will amend as more hi-res near-term guidance comes in.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........RAS
Short Term.....MJ
Long Term......MJ
Aviation.......RJS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1132 AM EST FRI DEC 4 2015
.UPDATE...
ISSUED AT 1132 AM EST FRI DEC 4 2015
VIS SAT NOW SHOWING THAT MOST OF THE RIVER VALLEY FOG HAS CLEARED
OUT THIS LATE MORNING HOUR. THEREFORE WILL UPDATE THE
NDFD GRIDS...ZFP...AND HWO TO REFLECT THIS THOUGHT. OTHERWISE
JUST SOME MINOR TWEAKS TO LATEST OBS AND TRENDS.
UPDATE ISSUED AT 958 AM EST FRI DEC 4 2015
VIS SAT CONTINUES TO SHOW RIVER VALLEY FOG...WHICH GIVEN THE TEMPS
THIS MORNING WILL LIKELY BE FREEZING FOG. NO ISSUES ROAD WISE ARE
EXPECTED THIS MORNING. THIS VALLEY FOG WILL CONTINUE TO DISSIPATE
THROUGH THE MORNING HOURS. UPDATED GRIDS TO REFLECT VALLEY FOG
LOCATIONS...OTHERWISE NOT MAJOR CHANGES NEEDED THIS UPDATE. DID
OPT TO UPDATE THE TEMP...DEWS... AND WINDS WITH LATEST OBS AND
TRENDS. GRIDS HAVE BEEN SENT TO NDFD.
UPDATE ISSUED AT 727 AM EST FRI DEC 4 2015
SINCE ALL TEMPERATURES ACROSS THE REGION ARE BELOW FREEZING...IT
IS LIKELY THAT WHATEVER PATCHY FOG HAS DEVELOPED ACROSS THE REGION
IS OF THE FREEZING VARIETY. AS SUCH...CHANGED WEATHER GRIDS FOR
THE NEXT COUPLE HOURS TO REFLECT PATCHY FREEZING FOG INSTEAD.
ALSO HIGHLIGHTED POTENTIAL IMPACTS IN THE HWO. HOWEVER...GIVEN THE
PATCHY NATURE OF THE FOG AND WITH LITTLE TO NO IMPACTS REPORTED
THUS FAR...DID NOT ISSUE ANY FURTHER PRODUCTS. MOST REPORTS THIS
MORNING HAVE BEEN FOR FROST RATHER THAN FOG. REGARDLESS...ANY
REMAINING FOG SHOULD BURN OFF OVER THE NEXT HOUR OR TWO AS WE
CONTINUE TO WARM UP. LOADED IN THE LATEST OBSERVATIONS TO MAKE
SURE THE NEAR TERM FORECAST WAS WELL ON TRACK WITH THE CURRENT
CONDITIONS. A NEW FORECAST PACKAGE WAS SENT OUT TO REFLECT THE
CHANGES IN FOG WORDING. ALL GRIDS WERE PUBLISHED AND SENT TO
NDFD/WEB.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 242 AM EST FRI DEC 4 2015
HIGH PRESSURE IS CURRENTLY DIRECTLY OVERHEAD THE STATE OF KENTUCKY
AS OF 7Z. THIS IS PROVIDING LIGHT WINDS AND STRONG SUBSIDENCE DURING
THE OVERNIGHT HOURS. WENT AHEAD AND LOWERED SOME OF THE DEEPER
VALLEY LOCATIONS LOW TEMPERATURES FOR EARLY THIS MORNING GIVEN THE
CURRENT OBSERVATIONS.
OTHERWISE...EXPECT QUIET AND CLEAR CONDITIONS THROUGH THE DURATION
OF THE SHORT TERM PERIOD AS THE HIGH PRESSURE REMAINS OVERHEAD.
AFTERNOON TEMPERATURES WILL CONTINUE TO SHOW AN INCREASING
TREND...WITH HIGHS TODAY TOPPING OUT AROUND THE 50 DEGREE
MARK...THEN CLIMBING TO THE MID TO UPPER 50S BY TOMORROW. STRONG
SUBSIDENCE AND MAXIMUM RADIATIONAL COOLING OVERNIGHT TONIGHT WILL
PROMOTE ANOTHER RIDGE VALLEY SPLIT AND SIGNIFICANT DIURNAL
DROPS...WITH UPPER 20S TO AROUND 30 EXPECTED ON THE RIDGES FOR
LOWS...AND LOW TO MID 20S IN THE VALLEYS.
THE ONE CONCERN DURING THIS FORECAST PERIOD WILL BE THE AMOUNT OF
DRY AIR BEING USHERED INTO THE REGION UNDER THE INFLUENCE OF THIS
HIGH PRESSURE SYSTEM. THIS WILL CREATE LOW DEW POINTS AND LOW RH
SITUATIONS BOTH THIS AFTERNOON...AND EVEN MORE SO SATURDAY
AFTERNOON. LUCKILY...WINDS WILL BE LIGHT AND PREVIOUS DAYS RAINS
WILL HELP TO MITIGATE SOME OF THE FIRE CONCERNS...BUT THIS WILL
CONTINUE TO BE SOMETHING TO MONITOR THROUGH THE UPCOMING WEEKEND.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 458 AM EST FRI DEC 4 2015
THE EXTENDED PERIOD WILL START OUT DRY AND PLEASANT...WITH ABOVE
NORMAL TEMPERATURES EXPECTED DURING THE DAY ON SUNDAY.
HOWEVER...CONDITIONS WILL START OUT QUITE COLD ACROSS THE AREA ON
SUNDAY MORNING...WITH LOWS DROPPING INTO THE LOW TO MID 20S IN OUR
VALLEYS...WHILE THE SURROUNDING RIDGES ONLY FALL INTO THE LOW TO
MID 30S. THE WEATHER IS EXPECTED TO REMAIN DRY THROUGH EARLY
MONDAY EVENING. AFTER MONDAY EVENING...HOWEVER...THE MODEL DATA
BEGINS TO DIVERGE...LEAVING US WITH AN UNCERTAIN FORECAST FROM
MONDAY NIGHT ONWARD. FOR NOW...WITH THE MODELS SHOWING A SERIES OF
FAST MOVING SHORT WAVES EJECTING OUT OF THE PLAINS AND ACROSS THE
EASTERN THIRD OF THE CONUS...DECIDED TO GO WITH LOW PRECIPITATION
CHANCES SUNDAY NIGHT THROUGH LATE MONDAY NIGHT. AFTER ANOTHER
POSSIBLE DRY PERIOD TUESDAY AND TUESDAY NIGHT...INTRODUCED MORE
RAIN CHANCES WEDNESDAY THROUGH THURSDAY...AS THE ECMWF MODEL TRIES
TO BRING A FAIRLY WELL DEVELOPED AREA OF LOW PRESSURE OUT OF THE
PLAINS AND ACROSS THE UPPER MISSISSIPPI VALLEY AND GREAT LAKES
REGIONS. THE SURFACE FRONT THAT WOULD BE ASSOCIATED WITH THIS
UPPER LOW WOULD WHAT WOULD BRING RAINFALL TO OUR AREA.
HOWEVER...THE GFS MODEL IS DRY FOR THURSDAY...WHEN THE ECMWF HAS
AN AREA OF RAINFALL AFFECTING THE AREA. WITH THAT IN MIND...WENT
WITH ONLY A SLIGHT CHANCE OF RAIN ACROSS EASTERN KENTUCKY FOR THE
WEDNESDAY THURSDAY TIME FRAME.
TEMPERATURES ACROSS THE AREA ARE EXPECTED TO BE GENERALLY ABOVE
NORMAL THROUGH OUT THE PERIOD...WITH DAY TIME HIGHS IN THE MID TO
UPPER 50S AND OVERNIGHT LOWS IN THE MID TO UPPER 30S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 656 AM EST FRI DEC 4 2015
A FEW INSTANCES OF PATCHY FOG HAVE BEEN REPORTED AT KSME AND KSYM
THIS MORNING...AND GIVEN THAT TEMPERATURES ARE BELOW FREEZING AT
THESE LOCATIONS...THIS IS LIKELY A FREEZING FOG SET UP. IMPACTS
SHOULD BE MINIMAL HOWEVER...AND FOG TO BURN OFF OVER THE NEXT 1
TO 2 HOURS AS WE START WARMING. OTHERWISE...HIGH PRESSURE WILL
REMAIN IN CONTROL OF THE REGION THROUGHOUT THE TAF PERIOD...
RESULTING IN LIGHT WINDS AND VFR/CLEAR CONDITIONS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...JMW
LONG TERM...AR
AVIATION...JMW
Area Forecast Discussion
National Weather Service Louisville KY
1057 AM EST FRI DEC 4 2015
...Forecast Update...
Issued at 1055 AM Fri Dec 4 2015
Fog is finally dissipating in a lot of the valleys, but the more
extensive area of fog/stratus over Indiana is going nowhere fast.
Have updated products to remove the fog mention, except over our
northernmost counties in southern Indiana, where the clouds/fog will
hang on for much of the afternoon. Temps are just warm enough that
in daylight conditions, freezing fog should not be as much of an
issue as it had been earlier. Therefore will just keep it plain old
fog. Have clipped max temps by several degrees where the clouds and
fog remain, but if it`s persistent enough, even the mid 40s in the
revised forecast may be too generous. Still on track for around 50
elsewhere.
Issued at 925 AM Fri Dec 4 2015
Patchy freezing fog is mostly dissipating based on latest METARs and
area webcams. Still seeing some of the deeper river valleys pretty
well socked in, so will take a bit slower approach to removing the
early fog wording from the ZFP. A more extensive area of fog/stratus
sits over Indiana just north of our CWA boundary, and I have little
confidence that it will go anywhere given poor mixing under a 1037mb
high pressure, and low December sun angle. That said, the current
forecast should be pretty well on track, so will just refresh to
pull the fog wording as the valleys finally start to mix a bit, and
will keep an eye on whether the stratus deck tries to creep into our
Indiana counties.
.SHORT TERM (Now through Saturday)...
Issued at 300 AM EST Fri Dec 4 2015
In the near term, high pressure will drift overhead early this
morning and then move slowly eastward during the day today. IR
satellite imagery reveals clear skies across the region. A decent
ridge/valley decoupling has taken place with the cooler valleys
presently sitting in the mid 20s with upper 20s to around 30
elsewhere. Dry air is abundant aloft across the region. However,
we do have some low-level moisture down near the surface which may
result in some areas of freezing fog this morning. The best chances
for the fog look to be across our southern Indiana counties and in
the KY river valley region of central KY. Temperatures may cool a
few more degrees before sunrise with most locations seeing readings
in the low-mid 20s in the valleys and in the mid-upper 20s elsewhere.
For Today through Saturday, quiet weather is expected as high
pressure will continue to dominance our weather pattern. Highs this
afternoon will warm into the upper 40s to around 50 in the north
with lower 50s likely across southern KY. Another cool night looks
likely tonight with lows in the valleys cooling into the lower-mid
20s with mid-upper 20s elsewhere. We will pick up a bit more
southerly flow on Saturday with mostly sunny skies. Temperatures
look to warm into the lower 50s in the north with low-mid 50s across
the south.
.LONG TERM (Saturday Night through Thursday)...
Issued at 323 AM EST Fri Dec 4 2015
In the long term period, a progressive flow will remain in place
aloft with a series of compact upper level lows rolling from east to
west across the CONUS. The first of these will transverse our
region late Sunday and into the day on Monday. Moisture is not all
that plentiful with the system as return flow from the Gulf will not
have sufficient time to moisten up the column. However, model time-
height cross sections do suggest plenty of mid-high level cloud
cover to push through with this system. Ascent is not overly
strong, but forcing with the upper low (mainly due to steep lapse
rates) look to be enough to continue low chance PoPs in the Sunday
night/Monday time frame.
The upper flow will then flatten back out by Tuesday, only to re-
amplify as the next upper level low crosses the region Wednesday
night into Thursday as it ejects from the northern Plains. Again,
large scale ascent with this system is not overly impressive, but
enough moisture and lift look available to warrant low chance PoPs
in the Wed night/Thursday time frame...despite the blended guidance
being a little more optimistic on dry conditions.
Temperatures through the period look to run a little above seasonal
normals. Typical early December highs average in the upper 40s. The
latest guidance suggests daily highs in the lower to middle 50s with
overnight lows in the mid-upper 30s. The warmest day looks to be
Thursday where some upper 50s across the south will be possible.
Overall, not much in the way of change from the previous forecast.
Looking further out, a more active weather pattern looks to take
shape as we head into late next week and into the mid part of
December. Latest teleconnection pattern suggest a
+AO/+NAO/+PNA/+EPO pattern in place by late next week. These
indices would support the series of rolling upper level lows across
the CONUS. However, as we head down the road, the models suggest a
downward trend in all the indices as we head toward mid-month. As
this downward trend occurs, we`re likely to see an active weather
pattern set up across the central US and eventually into the Ohio
Valley.
Initially, we`ll be on the warm side of the pattern with the threat
of additional heavy rainfall and milder than normal temperatures. As
the indices slide toward the neutral/negative range, we`ll
gradually see the sensible weather catch up with a more seasonal
cold pattern emerging after mid-month. It should be noted that the
long term models have struggled with timing of the downtrend in the
teleconnection indices. Past verification shows that they tend to
drop the indices too quick...so it would not be surprising to see
the eventual return to seasonal cold to be delayed slightly in later
forecasts.
&&
.AVIATION (12Z TAF Update)...
Updated at 610 AM EST Fri Dec 4 2015
Patchy fog/mist this morning at SDF/LEX/BWG will burn off between 13-
14z. Latest satellite imagery shows a LIFR stratus deck over east-
central IL and central IN, trying to expand southward. HRRR is
capturing this somewhat, best of the hi-res models, and takes it
southward to near the Ohio River in a few hours. It then should
either scatter out due to daytime mixing or retreat back to the
north. Given this though, still think SDF will remain clear but will
have to watch trends closely as models sometime poorly handle
shallow moisture within an inversion.
Otherwise, expect light/variable winds through the period. Another
clear/calm night will promote light fog formation at all sites,
starting after 06z.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........RAS
Short Term.....MJ
Long Term......MJ
Aviation.......ZBT
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
534 PM EST FRI DEC 4 2015
.SYNOPSIS...
RIDGE OF HIGH PRESSURE WILL BRING DRY WEATHER AND SLOWLY
MODERATING TEMPERATURES THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
WITH 530PM UPDATE...UPDATED HOURLY TEMPERATURE TRENDS AS WELL AS
SKY COVER. AS THE PREVIOUS DISCUSSION ALREADY MENTIONED...STRATUS
REMAINS OVER OHIO AND PENNSYLVANIA...BUT JUST OUTSIDE OF THE
FORECAST AREA. ALTHOUGH THE HRRR SHOWS THE STRATUS MOVING INTO THE
REGION AS IT CONTINUES TO BURN OFF...IT IS ALSO THE ONLY MODEL
THAT DEPICTS THE CLOUDS...SOMETHING THE OTHER MODELS ARE CLEARLY
FAILING ON. ESSENTIALLY WILL CONTINUE WITH THE PERSISTENCE
FORECAST. PREVIOUS DISCUSSION FOLLOWS.
MAINLY CLEAR SKIES ARE ANTICIPATED OVERNIGHT AS RIDGE OF HIGH
PRESSURE MOVES OVER THE REGION. THE HRRR MODEL SUGGESTS THAT
REMAINING STRATUS OVER OHIO THAT DOESN`T BURN OFF THIS AFTERNOON
MAY MOVE OVER THE REGION...BUT NOT CONFIDENT THAT THIS IS
REALISTIC SINCE THE BACK EDGE IS BURNING OFF RATHER QUICKLY. WITH
THIS IN MIND...EXPECT RADIATIONAL COOLING TO SUPPORT TEMPERATURES
IN THE 20`S CWA-WIDE.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
CLEAR AND DRY CONDITIONS WILL PERSIST THROUGH THE WEEKEND AS HIGH
PRESSURE SETTLES OVERHEAD. ALTHOUGH THERE WILL BE LITTLE
MIXING...ABUNDANT SUNSHINE AND WARMING MID LEVELS SHOULD SUPPORT
ABOVE NORMAL DAYTIME TEMPERATURES. NIGHTTIME TEMPERATURES
HOWEVER...SHOULD REMAIN NEAR NORMAL WITH STRONG RADIATIONAL
COOLING EXPECTED.
ON MONDAY...THE APPROACH OF AN UPPER TROUGH WILL BRING AN INCREASE
IN CLOUD COVER AND COOLER TEMPERATURES HOWEVER MOST OF THE
MOISTURE AND LIFT WILL REMAIN SOUTH...SO LOW CHANCE POPS WERE
CARRIED THROUGH THE END OF THE PERIOD.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
BLEND OF MODELS CONSISTENT IN MOVING LOW PRESSURE SOUTH AND EAST
OF REGION THROUGH TUESDAY KEEPING CLOUDS ACROSS THE REGION.
GENERAL ZONAL FLOW ALOFT WILL KEEP TEMPERATURES MILD THROUGH THE
EXTENDED PERIOD. HARD TO TIME SHORTWAVES IN FAST FLOW MAY BRING
A LOW CHANCE FOR SHOWERS LATE WEEK.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
MIXING UNDER HIGH PRESSURE WILL BRING GENERAL VFR WITH LIGHT WEST
WINDS INTO THE EVENING. MAINLY CLEAR WITH LIGHT WINDS OVERNIGHT.
.OUTLOOK...SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS THROUGH THE PERIOD.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
309 PM EST FRI DEC 4 2015
.SYNOPSIS...
RIDGE OF HIGH PRESSURE WILL BRING DRY WEATHER AND SLOWLY
MODERATING TEMPERATURES THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
MAINLY CLEAR SKIES ARE ANTICIPATED OVERNIGHT AS RIDGE OF HIGH
PRESSURE MOVES OVER THE REGION. THE HRRR MODEL SUGGESTS THAT
REMAINING STRATUS OVER OHIO THAT DOESN`T BURN OFF THIS AFTERNOON
MAY MOVE OVER THE REGION...BUT NOT CONFIDENT THAT THIS IS
REALISTIC SINCE THE BACK EDGE IS BURNING OFF RATHER QUICKLY. WITH
THIS IN MIND...EXPECT RADIATIONAL COOLING TO SUPPORT TEMPERATURES
IN THE 20`S CWA-WIDE.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
CLEAR AND DRY CONDITIONS WILL PERSIST THROUGH THE WEEKEND AS HIGH
PRESSURE SETTLES OVERHEAD. ALTHOUGH THERE WILL BE LITTLE
MIXING...ABUNDANT SUNSHINE AND WARMING MID LEVELS SHOULD SUPPORT
ABOVE NORMAL DAYTIME TEMPERATURES. NIGHTTIME TEMPERATURES
HOWEVER...SHOULD REMAIN NEAR NORMAL WITH STRONG RADIATIONAL
COOLING EXPECTED.
ON MONDAY...THE APPROACH OF AN UPPER TROUGH WILL BRING AN INCREASE
IN CLOUD COVER AND COOLER TEMPERATURES HOWEVER MOST OF THE
MOISTURE AND LIFT WILL REMAIN SOUTH...SO LOW CHANCE POPS WERE
CARRIED THROUGH THE END OF THE PERIOD.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
BLEND OF MODELS CONSISTENT IN MOVING LOW PRESSURE SOUTH AND EAST
OF REGION THROUGH TUESDAY KEEPING CLOUDS ACROSS THE REGION.
GENERAL ZONAL FLOW ALOFT WILL KEEP TEMPERATURES MILD THROUGH THE
EXTENDED PERIOD. HARD TO TIME SHORTWAVES IN FAST FLOW MAY BRING
A LOW CHANCE FOR SHOWERS LATE WEEK.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
STRATUS STILL HOLDING ON AT KFKL BUT SHOULD MIX OUT BY 20Z OR SO.
OTHERWISE MIXING UNDER HIGH PRESSURE WILL BRING GENERAL VFR WITH
LIGHT WEST WINDS INTO THE EVENING. MAINLY CLEAR WITH LIGHT WINDS
OVERNIGHT.
.OUTLOOK...SATURDAY THROUGH TUESDAY/...
VFR CONDITIONS THROUGH THE PERIOD.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
115 PM EST FRI DEC 4 2015
.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY WEATHER AND SLOWLY MODERATING
TEMPERATURES THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
CURRENT SATELLITE REFLECTS THE HRRR MODEL FORECAST FROM THIS
MORNING. THUS...NO NEAR TERM CHANGES WERE NEEDED AS SUNSHINE AND
MIXING SHOULD CONTINUE TO BURN OFF STRATUS ACROSS THE WESTERNMOST
ZONES THROUGH EARLY AFTERNOON AND HIGH TEMPERATURES SHOULD REACH
OR EXCEED NORMAL VALUES.
MAINLY CLEAR SKIES ARE ANTICIPATED OVERNIGHT AS RIDGE OF HIGH
PRESSURE MOVES OVER THE REGION. THE HRRR MODEL SUGGESTS THAT
REMAINING STRATUS OVER OHIO THAT DOESN`T BURN OFF THIS AFTERNOON
MAY MOVE OVER THE REGION...BUT NOT CONFIDENT THAT THIS IS
REALISTIC SINCE THE BACK EDGE IS BURNING OFF RATHER QUICKLY. WITH
THIS IN MIND...EXPECT RADIATIONAL COOLING TO SUPPORT TEMPERATURES
IN THE 20`S CWA-WIDE.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
CLEAR AND DRY CONDITIONS WILL PERSIST THROUGH THE WEEKEND AS HIGH
PRESSURE SETTLES OVER THE REGION. ALTHOUGH THERE WILL BE LITTLE
MIXING...ABUNDANT SUNSHINE AND WARMING MID LEVELS SHOULD SUPPORT
ABOVE NORMAL DAYTIME TEMPERATURES. NIGHTTIME TEMPERATURES
HOWEVER...SHOULD REMAIN NEAR NORMAL WITH STRONG RADIATIONAL
COOLING EXPECTED.
ON MONDAY...THE APPROACH OF AN UPPER TROUGH WILL BRING AN INCREASE
IN CLOUD COVER AND COOLER TEMPERATURES HOWEVER MOST OF THE
MOISTURE AND LIFT WILL REMAIN SOUTH...SO LOW CHANCE POPS WERE
CARRIED THROUGH THE END OF THE PERIOD.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
BLEND OF MODELS CONSISTENT IN MOVING LOW PRESSURE SOUTH AND EAST
OF REGION THROUGH TUESDAY KEEPING CLOUDS ACROSS THE REGION.
GENERAL ZONAL FLOW ALOFT WILL KEEP TEMPERATURES MILD THROUGH THE
EXTENDED PERIOD. HARD TO TIME SHORTWAVES IN FAST FLOW MAY BRING
A LOW CHANCE FOR SHOWERS LATE WEEK.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
STRATUS STILL HOLDING ON AT KFKL BUT SHOULD MIX OUT BY 20Z OR SO.
OTHERWISE MIXING UNDER HIGH PRESSURE WILL BRING GENERAL VFR WITH
LIGHT WEST WINDS INTO THE EVENING. MAINLY CLEAR WITH LIGHT WINDS
OVERNIGHT.
.OUTLOOK...SATURDAY THROUGH TUESDAY/...
VFR CONDITIONS THROUGH THE PERIOD.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1247 PM EST FRI DEC 4 2015
.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY WEATHER AND SLOWLY MODERATING
TEMPERATURES THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
MADE A NEAR TERM UPDATE TO SLIGHTLY ADJUST CLOUD COVER THROUGH THE
DAY BASED ON THE LATEST HI RES MODELS THAT SEEMED TO KEY ON THE
STRATUS OVER OHIO. WHILE THE HRRR SLIDES IT JUST INTO OUR
WESTERN-MOST ZONES...THAT APPEARS THAT WILL BE AS FAR AS IT GETS
BEFORE LOW LEVEL MIXING RESUMES AND SCATTERS OUT WHAT`S LEFT OF
THE CLOUD DECK OVER THE REGION.
TEMPERATURES WILL REMAIN RATHER STAGNANT UNTIL THE STRATUS
CLEARS. AFTER THAT TIME...SUFFICIENT INSOLATION SHOULD SUPPORT
HIGH TEMPERATURES JUST A TOUCH ABOVE NORMAL BY AFTERNOON.
CLEAR SKIES WILL CONTINUE INTO TONIGHT. DEWPOINTS WILL REMAIN LOW
AND SURFACE HIGH PRESSURE WILL MEANDER NEARBY. THIS SHOULD ALLOW
FOR FAIRLY EFFICIENT RADIATIONAL COOLING WITH WIDESPREAD LOWS IN
THE 20S.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
CLEAR AND DRY CONDITIONS WILL PERSIST THROUGH THE WEEKEND AS HIGH
PRESSURE SETTLES OVER THE REGION. UNDER ABUNDANT SUNSHINE...HIGH TEMPERATURES
WILL WARM THROUGH THE WEEKEND AS AXIS OF THE UPPER RIDGE SLOWLY
SHIFTS EAST AND CALM WINDS STIR FROM THE SOUTH. NIGHTTIME LOWS
WILL REMAIN NEAR OR JUST BELOW FREEZING AS THE CLEAR CONDITIONS
WILL LEAD TO RADIATIONAL COOLING AND DE-COUPLING OF THE LOWER
ATMOSPHERE. TAX
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
BLEND OF MODELS CONSISTENT IN MOVING LOW PRESSURE SOUTH AND EAST
OF REGION THROUGH TUESDAY KEEPING CLOUDS ACROSS THE REGION.
GENERAL ZONAL FLOW ALOFT WILL KEEP TEMPERATURES MILD THROUGH THE
EXTENDED PERIOD. HARD TO TIME SHORTWAVES IN FAST FLOW MAY BRING
A LOW CHANCE FOR SHOWERS LATE WEEK.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
STRATUS STILL HOLDING ON AT KFKL BUT SHOULD MIX OUT BY 20Z OR SO.
OTHERWISE MIXING UNDER HIGH PRESSURE WILL BRING GENERAL VFR WITH
LIGHT WEST WINDS INTO THE EVENING. MAINLY CLEAR WITH LIGHT WINDS
OVERNIGHT.
.OUTLOOK...SATURDAY THROUGH TUESDAY/...
VFR CONDITIONS THROUGH THE PERIOD.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
322 PM CST FRI DEC 4 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 323 PM CST FRI DEC 4 2015
SOUTHWEST FLOW WILL CONTINUE TO BRING SEASONABLY WARM
TEMPERATURES ACROSS THE UPPER MIDWEST. THE MAIN CONCERN IS THE
WIND POTENTIAL ON THE LEE SIDE OF THE BUFFALO RIDGE ACROSS FAR
WESTERN MN. A FEW OF THE HIRES MODELS SHOW GUST NEAR 50KTS...BUT
THOSE MODELS ARE CURRENTLY OVER DOING THE WINDS ACROSS THE
DAKOTAS. BUFR SOUNDINGS OFF THE RAP AND HRRR KEEP THE WINDS ABOVE
THE BOUNDARY LAYER. WITH THAT SAID...COULD SEE 35-40KT GUSTS LATE
TONIGHT AS WINDS CROSS THE RIDGE...AND MAY NEED A WIND HEADLINE
TONIGHT FOR YELLOW MEDICINE OR LAC QUI PARLE COUNTIES IF THE WINDS
ARE ABLE TO BREAK THROUGH THE INVERSION DOWN TO THE SURFACE.
CONFIDENCE WAS TOO LOW TO ISSUE ONE AT THIS TIME.
A NARROW LONG WAVE TROUGH WILL APPROACH THE REGION FROM THE WEST
LATE SATURDAY. EXPECT CLOUDS TO INCREASE IN RESPONSE TO THIS
WAVE...AND FORECAST SOUNDINGS SHOW SOME DRIZZLE/SPRINKLES POSSIBLE
AS WELL. SATURDAYS TEMPS WILL BE SIMILAR TO TODAY...WITH MID 40S
COMMON ACROSS THOSE AREAS THAT DO NOT HAVE SNOW COVER.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 323 PM CST FRI DEC 4 2015
CONTINUANCE OF ABOVE NORMAL TEMPERATURES AND DRY WEATHER WILL
DESCRIBE THE BULK OF THE LONG TERM PERIOD.
TO START OFF THE PERIOD HOWEVER...A WEAK COLD FRONT WILL BE
TRACKING ACROSS THE AREA ON SATURDAY NIGHT. ASSOCIATED MOISTURE
AND FORCING ARE NEGLIGIBLE...SO EXPECT ANY RESULTANT PRECIP TO BE
MOSTLY IN THE FORM OF DRIZZLE. ABSENCE OF MOISTURE IN THE
DENDRITIC LAYER SHOULD MEAN THE PRECIP WILL BE OF THE LIQUID
VARIETY.
SUNDAY INTO THE UPCOMING WEEK FEATURES THE PERSISTENCE OF MID
LEVEL RIDGING...WITH TEMPERATURES AVERAGING 12-18 DEGREES ABOVE
CLIMATOLOGICAL NORMALS.
WHILE THE MAJORITY OF NEXT WEEK LOOKS DRY AND WARM...THE RIDGE
DOES LOOK TO BREAK DOWN LATE IN THE WEEK. THERE ARE STILL NOTABLE
DIFFERENCES BETWEEN THE GFS AND ECMWF...BUT THERE WOULD LIKELY BE
ANOTHER UPTICK IN TEMPERATURES AHEAD OF THE SYSTEM TOWARD THE END
OF THE WEEK FOLLOWED BY RAIN/SNOW CHANCES FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1200 PM CST FRI DEC 4 2015
VFR CONDITIONS WILL GIVE WAY TO MVFR/IFR CEILINGS LATER TONIGHT
AND ON SATURDAY. A FEW RAIN SHOWERS ARE POSSIBLE BUT THERE IS NOT
SUFFICIENT MOISTURE FOR WIDESPREAD PRECIPITATION. SOUTHERLY WINDS
WILL INCREASE AT THE SURFACE WITH GUSTS NEAR 20KTS...BUT MORE
IMPORTANTLY A LOW LEVEL JET WILL DEVELOP WITH 50KTS OF WIND AT
2000FT AGL...SO WIND SHEAR WILL ALSO BE AN ISSUE.
KMSP...
IN ADDITION TO THE GENERAL DISCUSSION ABOVE...FORECAST SOUNDINGS
SHOW LOW LEVEL MOISTURE LATER TONIGHT THROUGH SATURDAY...SO HAVE
GONE WITH MVFR CLOUDS DURING THIS PERIOD. LOW LEVEL WIND SHEAR IS
MORE SPEED RELATED THAN DIRECTIONAL.
/OUTLOOK FOR KMSP/
SAT NIGHT...VFR. SLGT CHC -RA LATE. WINDS SW 10-15 KTS GUSTING 20
KTS.
SUN...VFR. WINDS W TO SW 5 KTS.
MON...VFR. WINDS S 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...LS
AVIATION...JRB
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1250 PM EST FRI DEC 4 2015
.SYNOPSIS...HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE
WEEKEND. LOW PRESSURE MOVES NORTH OFF OF THE CAROLINA COAST EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 945 AM FRIDAY...
WATER VAPOR SHOWED VERY DRY MID-LEVEL AIR OVER CENTRAL NORTH
CAROLINA...AND RAP SOUNDINGS SHOW DRY AIR CONTINUING THROUGH THE
COLUMN THROUGH TODAY...AND INTO TONIGHT. ALTHOUGH THERE IS A
WEAKNESS IN HEIGHTS ALOFT AND A MODEST SHEAR AXIS IN PLACE AS ALSO
NOTED ON WATER VAPOR AND ON THE FORECAST GUIDANCE...K INDICES ARE
VERY NEGATIVE AND SUBSIDENCE PREVAILS. CIRRUS WAS FINALLY MOVING OFF
TO THE EAST AS THE UPPER- AND MID-LEVEL JETS MOVE EAST...WHICH BY
THE MID AFTERNOON SHOULD BE AT OR JUST OFF OF THE NORTH CAROLINA
COAST. A FEW GUSTS WITH MIXING IN THE TEENS KNOTS...TO EARLY
AFTERNOON...SHOULD GRADUALLY SUBSIDE WITH LIGHT WINDS THROUGHOUT
CENTRAL NORTH CAROLINA BY EVENING. HIGHEST GUSTS IN A RELATIVE SENSE
SHOULD BE TOWARD KFAY...KCTZ... KGSB...AND KRWI WHERE THE SURFACE
GRADIENT IS JUST SLIGHTLY TIGHTER AND 925MB WINDS ARE
STRONGER...THOUGH THESE SUBSIDE TO LESS THAN 10KT THIS AFTERNOON.
TEMPERATURES HAVE RISEN QUICKLY WITH SUN EARLY THIS MORNING AND
OPTED TO RAISE MAXES IN MOST LOCATIONS BUT JUST A DEGREE OR
TWO...CLOSER TO THE MAV MOS GUIDANCE AND IN CONJUNCTION WITH VALUES
NOTED BY 1000-850MB THICKNESSES.
DRY AND SEASONABLY COOL CONDITIONS CONTINUE THROUGH SATURDAY. MIN
TEMPS TONIGHT WILL MAINLY BE NEAR OR SLIGHTLY BELOW FREEZING THOUGH
THE NORMALLY COLDER LOCATIONS WILL BE IN THE UPPER 20S. HIGH
TEMPERATURES SATURDAY WILL AVERAGE A DEGREE OR TWO WARMER...MID
TO UPPER 50S.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 320 AM FRIDAY...
HIGH PRESSURE AT THE SURFACE AND ALOFT WILL REMAIN OVERHEAD SATURDAY
NIGHT THROUGH SUNDAY THEN DRIFT EAST AND WEAKEN SUNDAY NIGHT. THE
LOW LEVEL AIR MASS WILL CONTINUE TO MODIFY...SUPPORTING HIGH TEMPS
SUNDAY WELL INTO THE 50S TO AROUND 60. STILL CHILLY SATURDAY NIGHT
WITH MIN TEMPS NEAR FREEZING...UPPER 20S AT THE NORMALLY COLDER
LOCATIONS. INCREASING MOISTURE THROUGH THE COLUMN WILL RESULT IN
"WARMER" OVERNIGHT TEMPS IN THE 30S TO AROUND 40. BASED ON MODEL
TRENDS OF A SLOWER ARRIVAL OF DEEPER MOISTURE AND ENOUGH LIFT TO
GENERATE LIGHT PRECIP...HAVE REMOVED THE MENTION OF SLIGHT CHANCE
POPS FROM THE FORECAST FOR SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 225 AM FRIDAY...
MONDAY THROUGH TUESDAY: MEDIUM RANGE MODELS CONTINUE TO STRUGGLE
WITH THE TRACK AND TIMING OF A MID LEVEL LOW EXPECTED TO SHIFT
EASTWARD FROM THE TN/OH VALLEY REGION MONDAY MORNING TO OFF THE MID
ATLANTIC COAST BY AT LEAST TUESDAY EVENING. BOTH THE ECMWF AND GFS
HAVE TRENDED NORTHWARD WITH THE TRACK OF THE MID LEVEL LOW THOUGH...
AND FURTHER OFFSHORE WITH A DEVELOPING COASTAL LOW DURING THIS TIME
FRAME. THIS WOULD RESULT IN LESS OF A CHANCE OF RAIN ON MONDAY INTO
TUESDAY FOR CENTRAL NC. HOWEVER... GIVEN THE DRAMATIC SHIFT IN THE
OPERATIONAL RUNS OF THE GFS AND ECMWF OVER THE LAST 24 HOURS WILL
CONTINUE TO HOLD ONTO SOME LOW END CHANCE POPS FOR MONDAY INTO
MONDAY NIGHT... WITH THE BEST CHANCE ACROSS THE SOUTHEAST/EASTERN
PORTIONS OF CENTRAL NC (GENERALLY EAST OF RALEIGH). GIVEN THIS TREND
IN THE MODELS WILL RAISE HIGH TEMPS SOME FOR MONDAY AND KEEP HIGHS
SIMILAR FOR TUESDAY. THIS YIELDS HIGHS IN THE MID TO UPPER 50S...
WITH EVEN A FEW LOCATIONS POSSIBLY TOUCHING 60. LOW TEMPS TUESDAY
MORNING ARE EXPECTED TO RANGE FROM THE MID 30S NW TO THE LOWER TO
MID 40S SE (DEPENDING ON THE AMOUNT OF CLOUD COVER AND POSSIBLE
PRECIP). OVERALL... HAVE TREND THE FORECAST MORE TO THE LAST TWO
RUNS OF THE ECMWF... GIVEN BETTER RUN TO RUN CONTINUITY.
TUESDAY NIGHT THROUGH THURSDAY: AFTER A BRIEF PERIOD OF MID LEVEL
S/W RIDGING... MEDIUM RANGE MODELS STRUGGLE WITH A FAIRLY
PROGRESSIVE PATTERN OF FAST MOVING MID LEVEL DISTURBANCES IN A
GENERAL MEAN L/W BROAD TROUGH ACROSS THE EASTERN HALF OF THE
COUNTRY. GIVEN THESE HARD TO TIME DISTURBANCES EXPECTED TO MOVE
ACROSS THE REGION DURING THIS TIME FRAME... WILL KEEP TEMPS NEAR
NORMAL AS LOW LEVEL THICKNESS VALUES ARE PROGGED TO REMAIN NEAR
NORMAL. THIS YIELDS HIGHS IN THE MID TO UPPER 50S GENERALLY... WITH
LOWS IN THE 30S TO NEAR 40 SE... AND DRY CONDITIONS FOR NOW.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1250 PM FRIDAY...
VFR CONDITIONS PERSIST THROUGH...AND BEYOND...THE 18Z VALID TAF
PERIOD. NORTH-TO-NORTHEAST SURFACE WINDS DIMINISH SOME THIS EVENING.
MODEST GUSTINESS...IN THE TEENS KNOTS AND RELATIVELY A LITTLE HIGHER
TOWARD KFAY AND KRWI...WITH MIXING OCCURS AGAIN SATURDAY MORNING.
THE NAM GUIDANCE SUGGESTS THE POTENTIAL FOR VERY LOW-LEVEL MOISTURE
MOVING INTO CENTRAL NORTH CAROLINA TOWARD INTERSTATE 95 ON THE
NORTHEAST FLOW EARLY SUNDAY MORNING. THE GFS IS DRIER...AND
CURRENTLY IT WOULD SEEM THE HIGHER PROBABILITY OF ANY LOW CLOUDS
WILL REMAIN CLOSER TO THE COAST WHERE THE AXIS OF HIGHER MOISTURE
SHOULD BE ON THE CONSENSUS OF BOTH NAM AND GFS MOISTURE FIELDS BELOW
1000MB. THERE IS A CHANCE OF SUB-VFR CONDITIONS IN CENTRAL NORTH
CAROLINA OVERNIGHT SUNDAY AND MONDAY...WITH THE HIGHER CHANCES AGAIN
TOWARD KFAY AND KRWI RELATIVE TO THE REST OF CENTRAL NORTH CAROLINA.
GOOD PROBABILITIES OF VFR CONDITIONS FOLLOW FOR TUESDAY AND
WEDNESDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...WSS/DJF
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
320 PM CST FRI DEC 4 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 320 PM CST FRI DEC 4 2015
MILD AND QUIET WEATHER WILL CONTINUE THROUGH SATURDAY.
AS OF 21 UTC...IT IS APPARENT THAT THE LOW-LEVEL INVERSION IS ONLY
SLOWLY BEING ERODED IN SOUTHERLY FLOW...AS SURFACE GUSTS ARE BEING
HELD UNDER 30 KT EVEN IN THE JAMES RIVER VALLEY. FORECAST SOUNDING
PROFILES FROM THE RAP AND HRRR CONTINUE TO SUPPORT WINDS AROUND
60 KT WITHIN 2000 FT AGL THROUGH EARLY EVENING IN EAST CENTRAL ND
AND SO WE WILL HAVE TO MONITOR FOR STRONGER GUSTS...BUT THE CHANCE
OF ADVISORY-TYPE GUSTS APPEARS TO BE DWINDLING.
A MODEST COLD FRONT WILL CROSS THE AREA TONIGHT...TURNING WINDS TO
THE WEST...AND COOLING THE AIR MASS A BIT BY SATURDAY WHEN 850-MB
TEMPERATURES ARE EXPECTED TO DROP TO +1 TO +3 C. HOWEVER...GIVEN
THE FAVORABLE LOW-LEVEL WESTERLY FLOW AND CONTINUED EROSION OF THE
SNOW PACK...WE STILL EXPECT HIGHS IN THE 40S F IN MANY PLACES ON
SATURDAY. IT ALSO APPEARS THAT THE NEAR-SURFACE LAYER WILL BE TOO
TURBULENT TO SUPPORT FOG FORMATION TONIGHT IN AREAS THAT HAVE HAD
SNOWMELT DURING THE DAY.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 320 PM CST FRI DEC 4 2015
THE MAIN HIGHLIGHTS IN THE LONG TERM PERIOD ARE ABOVE NORMAL HIGH
TEMPERATURES THROUGH THE PERIOD...WITH HIGHS IN THE 40S AND SOME 50S
ESPECIALLY SUNDAY AND WEDNESDAY. A COOLING TREND INITIATES FRIDAY
AND CONTINUES THROUGH THE UPCOMING WEEKEND. ALTHOUGH COOLER
CONDITIONS EXPECTED FRIDAY...HIGH TEMPERATURES STILL REMAIN ABOVE
NORMAL WITH HIGHS 35F TO 40F. THE OVERALL PATTERN OF A NEAR ZONAL
FLOW CONTINUES WITH QUICK MOVING SHORTWAVES AND ASSOCIATED SURFACE
FEATURES SLIDING ACROSS WESTERN AND CENTRAL NORTH DAKOTA. THE MAIN
DIFFERENCE ON THE 12Z GFS/ECMWF MODELS RUNS TODAY IS A MORE
WIDESPREAD CHANCE OF MOSTLY RAIN SHOWERS ON TUESDAY ACROSS WESTERN
AND CENTRAL NORTH DAKOTA. ALTHOUGH SOME SNOW SHOWERS ARE POSSIBLE
DURING THE EARLY MORNING. ANOTHER FAIRLY WEAK SHORTWAVE IS SLATED
FOR THURSDAY INTO THURSDAY NIGHT....WITH A POTENTIALLY STRONGER
SHORTWAVE FRIDAY INTO THE WEEKEND. HOWEVER IT IS EVIDENT JUST FROM
THE GFS ENSEMBLE HEIGHTS THAT NEXT WEEKENDS SHORTWAVE HAS A LOT OF
UNCERTAINTY...WITH SEVERAL POSSIBLE SOLUTIONS. THE SUPERBLEND
CURRENTLY HAS A SLIGHT CHANCE/CHANCE OF RAIN AND SNOW FRIDAY/FRIDAY
NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 320 PM CST FRI DEC 4 2015
SOUTHERLY WIND GUSTS OF 20 TO 30 KT ARE EXPECTED IN SOUTH CENTRAL
ND THIS AFTERNOON AND EARLY EVENING. EVEN STRONGER WINDS OF 50 TO
60 KT ARE EXPECTED AROUND 2000 FT AGL...PRODUCING LOW-LEVEL WIND
SHEAR AND SUGGESTIVE OF SOME RISK FOR SURFACE GUSTS OVER 30 KT.
VFR WEATHER IS GENERALLY EXPECTED THROUGH 18 UTC SATURDAY...BUT
THERE IS A LOW PROBABILITY OF MVFR CEILINGS AT BOTH KJMS AND KMOT
TONIGHT AND SATURDAY MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CJS
LONG TERM...KS
AVIATION...CJS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1228 PM CST FRI DEC 4 2015
.UPDATE...
ISSUED AT 1225 PM CST FRI DEC 4 2015
THE MAIN CHANGE WILL BE TO LOWER TEMPS OVER THE SNOW FIELD IN THE
VALLEY WITH TEMPS STRUGGLING IN THE MID/UPPER 20S WHILE LANGDON IS
48. THEREFORE...WILL TAILOR TEMPS TO THE SNOW/NO SNOW AREAS ONCE
AGAIN. IT STILL LOOKS WINDY WITH THE STRONGEST WINDS ALOFT IN THE
VALLEY IN THE 00-06Z TIMEFRAME...AND WE WILL BE VERY CLOSE IF NOT
INTO WIND ADVISORY CRITERIA AND WILL CONTINUE TO MONITOR.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 325 AM CST FRI DEC 4 2015
MAIN FORECAST CHALLENGE WILL BE TEMPERATURES. GOOD AGREEMENT WITH
MODELS ON MAIN DETAILS.
TEMPERATURES WILL BE THE PRIMARY CHALLENGE THROUGH THE PERIOD
BETWEEN AREAS WITH SNOW COVER VS NO SNOW. OVER A 20 DEGREES SPREAD
IN MAXIMUM TEMPERATURES YESTERDAY BASED JUST ON SNOW COVER. THIS
TREND WILL LIKELY CONTINUE AS LONG AS SNOW COVER EXISTS.
FOR TODAY SURFACE PRESSURE GRADIENT INCREASES FOR BREEZY
CONDITIONS HOWEVER WITH VERY SHALLOW MIXED LAYER STRONGER WINDS
ALOFT NOT LIKELY TO MIX DOWN. WARM COLUMN REMAINS IN PLACE SO MILD
TEMPERATURES TO CONTINUE. DIFFERENCE TODAY FROM YESTERDAY WILL BE
SOUTHERLY VS WESTERLY SURFACE WINDS. A SOUTH WIND COMING ACROSS
SNOW FIELD MAY SOMEWHAT LIMIT TEMPERATURE CLIMB ACROSS SNOW FREE
REGION ACROSS THE NORTHERN FA. MODEL GUIDANCE HAS STRUGGLED WITH
TEMPERATURES AS A RESULT OF SNOW COVER. RUC APPEARED MOST
REALISTIC WITH TEMPERATURES SO GENERALLY FOLLOWED ITS FORECAST.
NORTHERN AREAS MAY STAY JUST SHY OF 50 WITH REMAINDER OF FA
HOLDING IN THE 30S TO AROUND 40.
MIXING WILL HOLD TEMPERATURES UP TONIGHT WITH MINIMUMS AT OR ABOVE
AVERAGE HIGHS FOR THIS TIME OF THE YEAR.
BROAD MID LEVEL TROUGH WILL CROSS THE FA THIS WEEKEND. A WEAK COLD
FRONT WILL CROSS THE REGION SATURDAY. COLUMN LACKING MOISTURE SO A
BIT MORE CLOUD COVER AND WSHFT WILL BE THE ONLY AFFECTS WITH
FROPA. COLUMN COOLER SO TEMPERATURES MAY BE MORE UNIFORM ACROSS
THE FA BUT STILL WELL ABOVE AVERAGE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 AM CST FRI DEC 4 2015
MINIMAL WEATHER IMPACTS WILL CONTINUE REMAINDER OF THE WEEKEND.
WELL ABOVE AVERAGE TEMPERATURES WILL CONTINUE TO WORK ON SHRINKING
EXISTING SNOW PACK. APPEARS TO BE ENOUGH MIXING TO LIMIT NIGHT
TIME FOG DEVELOPMENT WITH DAY TIME MELTING BUT WILL NEED TO
MONITOR.
MODELS INITIALIZED WELL AND CONTINUE TO SHOW A GENERAL BROAD RIDGE
ACROSS THE NRN PLAINS. WITH THE UPPER RIDGE REMAINING IN
PLACE...EXPECT TEMPERATURES TO REMAIN ABOVE NORMAL. HOWEVER...TEMPS
WILL DEPEND ON ANY REMAINING SNOW PACK...AND INDICATIONS ARE IT WILL
CONTINUE TO ERODE...AS HIGH TEMPS LOOK TO BE IN THE UPPER 30S TO LOW
40S THRU THE PERIOD. OTHERWISE...A FEW IMPULSES OF ENERGY WILL
PROPAGATE THRU THE FLOW...BUT WITH A GENERALLY DRY COLUMN DO NOT
ANTICIPATE MUCH IN THE WAY OF PCPN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1225 PM CST FRI DEC 4 2015
VFR CONDS BUT WINDY. SOUTH WINDS WILL INCREASE BY LATE
AFTERNOON AS INVERSION ERODES AND MOST SITES WILL BE BREEZY
THROUGHOUT THE NIGHT. VFR TOMORROW MORNING WITH WINDS TURNING MORE
WESTERLY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...VOELKER
LONG TERM...HOPKINS/VOELKER
AVIATION...DK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1208 PM EST FRI DEC 4 2015
.SYNOPSIS...
SURFACE HIGH PRESSURE OVER THE MID MISSISSIPPI VALLEY WILL MOVE
SLOWLY EAST ACROSS THE OHIO VALLEY AND MOVE OFF THE MID ATLANTIC
COAST SUNDAY. THIS WILL ALLOW AN UPPER LEVEL TROUGH TO MOVE
ACROSS THE OHIO VALLEY EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...LOW STRATUS EVOLVING LARGELY AS EXPECTED. SATELLITE DOES
SHOW THE THINNING HINTED AT ON THE HRRR ACROSS NERN INDIANA AND
NWRN OH. DID ADJUST SKY GRIDS THERE JUST A BIT TO BE MORE
OPTIMISTIC FOR GETTING SUN INTO THE AREA FOR THE
AFTERNOON(...ANTICIPATED TO OCCUR FROM MID AFTERNOON ON). ALSO
THINNING AS EXPECTED ALONG THE EASTERN EDGE WHICH HAS ERODED
CLOUDS IN SERN MAHONING COUNTY AS WELL AS A PORTION OF STARK AND
HOLMES COUNTY. THIS WILL LIKELY PERSIST THROUGH THE AFTERNOON BUT
NOT OPTIMISTIC FOR A LARGE SCALE CLEARING FROM THE SOUTHEAST JUST
YET. EARLIER UPDATE ALSO INCLUDED A TEMPERATURE DECREASE FOR THE
AFTERNOON AND WILL REMAIN CLOSE TO THOSE NUMBERS.
ORIGINAL DISCUSSION...
FORECAST PROBLEM OF THE DAY IS HOW FAST THE CLOUD DECK ACROSS THE
CENTRAL AND EASTERN LAKES WILL ERODE. NONE OF THE MODELS HAVE A
CLUE ABOUT THE CLOUD COVER SINCE INVERSION TRAPPING MOISTURE BELOW
925MB. THERE ARE A FEW CLOUD BREAKS NOW...BUT THE 925 MB RIDGE AXIS
DOESNT REACH NW OHIO UNTIL THIS AFTERNOON SO HAVE SLOWED THE TIMING
OF THE CLOUD DECK UNTIL THIS AFTERNOON. IN FACT DO NOT THINK THE
EAST WILL TOTALLY CLEAR OUT UNTIL TONIGHT. AS A RESULT LOWER
FORECAST HIGHS A FEW DEGREES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
LAST REMAINING CLOUDS IN THE EAST SHOULD CLEAR OUT OVERNIGHT AS
THE RIDGE FINALLY MOVES OVER THE FORECAST AREA. SURFACE RIDGE
SHIFTS EAST OF THE AREA SATURDAY ALLOWING FOR A WARMUP. TEMPS
SHOULD WARM INTO THE UPPER 40S TO LOWER 50S THIS WEEKEND...WHICH
IS ROUGHLY 5-10 DEGREES ABOVE NORMAL FOR EARLY DECEMBER. MODELS
CONTINUE TO MOVE THE HIGH OFF THE MID ATLANTIC COAST EARLY SUNDAY.
THIS WILL ALLOW AN UPPER LEVEL TROUGH TO MOVE ACROSS THE OHIO
VALLEY ON MONDAY. BEST MOISTURE REMAINS WELL SOUTH OF THE FORECAST
AREA SO WILL CONTINUE WITH A DRY FORECAST THROUGH THE PERIOD.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
UNUSUALLY QUIET WEATHER WILL CONTINUE DURING THE LONG TERM PERIOD AS
HIGH PRESSURE AT THE SURFACE IS EXPECTED TO DOMINATE. HAVE MADE
ONLY MINOR CHANGES TO THE FORECAST. SOME MODEL DIFFERENCES BEGIN TO
CROP UP AT THE VERY END OF THE FORECAST PERIOD BUT WILL LET LATER
SHIFTS DEAL WITH THAT. TEMPERATURES DURING THE PERIOD WILL AVERAGE
5 TO 10 DEGREES ABOVE NORMAL WITH PARTLY CLOUDY SKIES MUCH OF THE
TIME.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
A SMALL AREA OF CLEARING HAS MADE IT`S WAY TO NE OHIO. IT SHOULD
LINGER OVER KCAK FOR ANOTHER HOUR AND AT KYNG FOR A COUPLE OF
HOURS. AFTER THAT IFR/MVFR CIGS WILL OVERSPREAD THE AREA AGAIN. IT
REMAINS VERY DRY ALOFT BUT THE BOUNDARY LAYER IS MOIST. TILL WE
GET ENOUGH MIXING THE LOW CLOUDS WILL PERSIST. BEST GUESS NOW IS
THAT THE CLOUDS WILL BEGIN TO BREAK UP AROUND MIDDAY. WILL KEEP
THE WESTERN SITES IFR TILL THEN AND BRING IFR INTO KCAK AND KYNG
IN A FEW HOURS. THERE SHOULD BE JUST ENOUGH DOWNSLOPING SW FLOW TO
KEEP CIGS AT KCLE AND KERI MVFR. ONCE THE CLOUDS BREAK UP SKIES
THE REMAINDER OF THE PERIOD SHOULD BE MAINLY CLEAR. SW TO WSW FLOW
WILL CONTINUE. WINDS SHOULD GRADUALLY LESSEN TODAY.
OUTLOOK...VFR CONDITIONS INTO EARLY NEXT WEEK AS HIGH PRESSURE
REMAINS IN CONTROL.
&&
.MARINE...
NO SIGNIFICANT CHANGES TO THE MARINE FORECASTS THIS
MORNING. MARGINAL SMALL CRAFT CONDITIONS WILL CONTINUE IN THE EAST
TODAY SO WILL LEAVE THE HEADLINES AS IS. HIGH PRESSURE WILL BUILD
OVER THE LAKE FROM THE SOUTH OVER THE WEEKEND. THIS WILL MAINTAIN A
LIGHT W TO SW FLOW. THE HIGH WILL EVENTUALLY LIFT OFF TO THE
NORTHEAST EARLY NEXT WEEK WITH VARIABLE FLOW UNDER 15 KNOTS
CONTINUING.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
LEZ147>149.
&&
$$
SYNOPSIS...DJB
NEAR TERM...DJB/TK
SHORT TERM...DJB
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA