Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/23/15
AREA FORECAST DISCUSSION
NWS ALBANY NY
415 PM EST SAT NOV 21 2015
.SYNOPSIS... A LOW PRESSURE WILL RACE NORTHEAST THROUGH THE EASTERN
GREAT LAKES TONIGHT...AND DRAG A COLD FRONT ACROSS THE REGION WITH
SCATTERED RAIN AND SNOW SHOWERS. ANY ACCUMULATION WILL BE CONFINED
TO RIM OF THE MOHAWK VALLEY AND ADIRONDACKS. BREEZY NORTHWEST WINDS
WILL BRING COOLER AIR BACK INTO THE AREA ON SUNDAY...ALONG WITH SOME
LAKE EFFECT SNOW SHOWERS OVER THE ADIRONDACKS. MAINLY DRY AND COLD
WEATHER IS EXPECTED ON MONDAY ALTHOUGH THERE COULD BE ADDITIONAL
SNOW SHOWERS ACROSS THE ADIRONDACKS.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 415 PM EST...STILL DRY ACROSS OUR REGION. HIGH PRESSURE JUST TO OUR
EAST WAS STILL IN CONTROL OF OUR WEATHER...WITH HIGH CLOUDS
INCREASING OVER OUR REGION AHEAD OF THE NEXT DISTURBANCE.
TEMPERATURES WERE GENERALLY IN THE 40S.
THIS DISTURBANCE WAS AN AREA OF LOW PRESSURE OVER OHIO
WHICH HAS PRODUCED A EARLY SEASON SNOWSTORM ACROSS PORTIONS
OF THE GREAT LAKES. THIS STORM WILL TRACK NORTHEASTWARD INTO
ONTARIO. IT WILL DRAG AN OCCLUDED FRONT THROUGH OUR REGION
LATE TONIGHT.
THE BEST FORCING AND MOISTURE WILL STAY WELL NORTH AND EAST
OF THE CAPITAL REGION.
INITIALLY ANY PRECIPITATION WILL START AS A RAIN SNOW MIX OVER
THE ADIRONDACKS BUT SHOULD CHANGE TO ALL SNOW OVERNIGHT. ACCUMULATIONS
LOOK MINOR AS SURFACE TEMPERATURES WILL ONLY BE MARGINALLY COLD
ENOUGH FOR ACCUMULATIONS. FOR TONIGHT WE ARE LOOKING FOR A COATING
TO TWO INCHES OVER THE ADIRONDACK PARK.
FURTHER SOUTH AND EAST SHOWERS WILL BE MOST SCATTERED. SNOW FLAKES
COULD MIX ANYWHERE BUT WILL LIKELY NOT PRODUCE ANY ACCUMULATION
AS THE QPF LOOKS VERY LIGHT WITH SOME AREAS NOT GETTING ANY MEASURABLE
AT ALL...ESPECIALLY SOUTH OF ALBANY.
OVERNIGHT LOWS WILL RANGE FROM THE UPPER 20S TO MID 30S. IN SOME CASES...
THEY MIGHT HAPPEN THIS EVENING BEFORE THICKER CLOUDS AND A BREEZE
KICKS IN WHICH BOTH MIGHT WARM THE BOUNDARY A LITTLE IN THE VALLEYS.
A SOUTH BREEZE WILL AVERAGE 5-15 MPH TONIGHT BECOME WESTERLY BY
DAYBREAK AS THE FRONT MOVES ON BY.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
AS THE FRONT MOVES ON BY...CHILLIER AIR WILL FILTER INTO THE REGION.
HOWEVER...WITH A WSW FLOW AND A GOOD DEAL OF SUNSHINE...TEMPERATURES
WILL ACTUALLY WARM TO NEAR 50 IN THE VALLEYS...WHILE HOLDING CLOSER
TO 40 ACROSS THE HIGHER TERRAIN. KEEP IN MIND THESE VALUES MIGHT
HAPPEN BY MIDDAY...WITH TEMPERATURES FALLING A BIT DURING THE
AFTERNOON.
IT WILL BE BREEZY WITH A WEST WIND 10-15 MPH...GUSTING TO 25 MPH
ESPECIALLY OVER THE HIGHER TERRAIN/MOHAWK VALLEY AND THE CAPITAL REGION.
WHILE MOST OF THE AREA WILL BE DRY WITH PARTIAL SUNSHINE...LAKE ENHANCED
CLOUDS AND PERHAPS SOME SNOW SHOWERS WILL PERSIST OVER
THE ADIRONDACKS. EVEN IF SURFACE TEMPERATURES ARE ABOVE FREEZING
ON SUNDAY...THE AIR WILL BE QUITE CHILLY ALOFT AND CERTAINLY VERTICAL
INSTABILITY AND UPSLOPE COULD GENERATE THESE SNOW SHOWERS EVEN IN
THE ABSENCE OF ANY PURE LAKE EFFECT.
HOWEVER...AFTER EXAMINING THE EXPERIMENTAL KVIE CSTAR PROGRAM...
IT NOW APPEARS THE INLAND LAKE EXTENT OFF OF ONTARIO WILL ONLY
BE ABOUT 50 MILES...LIMITED DUE TO SOME SHEAR IN THE COLUMN AND
DRY AIR IN THE MID LEVELS. THEREFORE PURE LAKE EFFECT SNOW
PLUMES MIGHT ONLY GRAZE HERKIMER AND LIKELY NOT EVEN REACH
HAMILTON COUNTIES. THEREFORE NO HEADLINES WERE ISSUED.
IF CONDITIONS LOOK DIFFERENT LATER ON...HEADLINES WILL BE RECONSIDERED.
ANY ADDITIONAL SNOW ACCUMULATIONS ON SUNDAY OVER THE ADIRONDACKS SHOULD
LIGHT...AN INCH OR LESS.
SUNDAY NIGHT THROUGH MONDAY NIGHT...LARGE HIGH PRESSURE WILL
BUILD TO OUR SOUTH. ADDITIONAL SHORT WAVE ENERGY ALONG
WITH ANOTHER MID LEVEL TROUGH ROLLING TO OUR NORTH...
COULD TRIGGER A FEW MORE BOUTS OF SNOW SHOWERS WITH ADDITIONAL
MAINLY MINOR ACCUMULATIONS OVER OUR ADIRONDACKS AND
PERHAPS CENTRAL MOHAWK VALLEY. THIS AGAIN ASSUMES THE MAIN
PLUMES OFF ONTARIO STAY MAINLY TO OUR WEST. IT WILL BE A CLOSE
CALL BUT RIGHT NOW THEY APPEAR TO JUST MISS MOST OF OUR AREA.
THE POTENTIAL IS THERE FOR 1-4 INCHES OF SNOWFALL WHEN IT IS ALL SAID AND
DONE...SPREAD OUT OVER SEVERAL PERIODS SO AGAIN NO LAKE EFFECT SNOW
ADVISORIES WERE ISSUED WITH THIS PACKAGE. KEEP IN MIND IF ANY
PLUME FROM LAKE ONTARIO WAS ABLE TO PENETRATE INTO HERKIMER OR
HAMILTON COUNTIES...AMOUNTS COULD BE LOCALLY A LITTLE HIGHER.
THE REMAINDER OF THE REGION SHOULD REMAIN MOSTLY DRY ALTHOUGH A SPRINKLE
OR FLURRY IS POSSIBLE ALONG WITH OCCASIONAL CLOUDINESS.
OTHERWISE IT LOOKS CHILLY BUT NOTHING OUT OF THE ORDINARY
FOR LATE NOVEMBER.
LOW TEMPERATURES MONDAY MORNING WILL BE MAINLY IN THE 20S...WITH SOME TEENS
IN THE COLDEST AREAS. HIGHS MONDAY WILL BE ONLY IN THE UPPER 20S TO MID 30S
HIGHER TERRAIN...CLOSE TO 40 IN THE VALLEYS.
BY TUESDAY...AS HIGH PRESSURE SLOWLY BEGINS TO BUILD ALOFT...THERE WILL BE
SLOW MODERATION IN THE AIRMASS. ANY LINGERING SNOW SHOWERS WILL
CEASE ACROSS THE ADIRONDACKS. OTHERWISE IT WILL BE MOSTLY SUNNY.
LOWS TUESDAY MORNING WILL RANGE FROM THE MID TEENS TO MID 20S.
HIGHS TUESDAY WILL RANGE FROM THE 30S OVER THE HIGHER TERRAIN...
LOWER TO MID 40S IN THE VALLEYS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE LONG TERM PERIOD WILL BE CHARACTERIZED BY MAINLY DRY WEATHER
WITH THE NEXT CHANCE FOR PRECIPITATION ACROSS THE REGION FRIDAY INTO
SATURDAY AS A FRONTAL BOUNDARY MOVES ACROSS THE REGION.
AT THE START OF THE LONG TERM PERIOD...THE LONG RANGE GUIDANCE
CONTINUES TO BE IN VERY GOOD AGREEMENT WITH THE EVOLUTION OF THE
LONG TERM PATTERN. MUCH OF THE LONG TERM PERIOD WILL BE DOMINATED BY
HIGH PRESSURE AT THE SURFACE AND UPPER-LEVEL RIDGING ALOFT. THIS
WILL RESULT IN AN EXTENDED PERIOD OF DRY WEATHER TUESDAY NIGHT
THROUGH THURSDAY NIGHT...INCLUDING THANKSGIVING...WITH PARTLY CLOUDY
SKIES.
A FRONTAL BOUNDARY WILL MOVE ACROSS THE REGION FRIDAY INTO THE
SATURDAY TIME PERIOD. THERE IS SOME DIFFERENCE IN THE LONG RANGE
GUIDANCE REGARDING THE TIMING OF THIS FRONTAL BOUNDARY...BUT HAVE
INDICATED CHANCE POPS DURING THIS TIMEFRAME FOR RAIN SHOWERS DURING
THE DAYTIME HOURS...AND A MIX OF RAIN/SNOW SHOWERS DURING THE
NIGHTTIME HOURS WITH THE BEST CHANCE FOR SNOW ACROSS THE HIGHER
TERRAIN.
TEMPERATURES DURING THE LONG TERM PERIOD WILL BE SLIGHTLY ABOVE
NORMAL FOR LATE NOVEMBER. HIGHS ON WEDNESDAY WILL RANGE FROM THE
UPPER 30S/LOW 40S ACROSS THE HIGHER TERRAIN TO THE MID AND UPPER 40S
IN VALLEY AREAS. HIGHS ON THURSDAY AND FRIDAY WILL RANGE FROM THE
UPPER 40S TO MID 50S. HIGHS ON SATURDAY WILL RANGE FROM NEAR 40 TO
NEAR 50. LOWS TUESDAY NIGHT WILL RANGE FROM THE MID TO UPPER
20S...UPPER 20S TO LOWER 30S WEDNESDAY NIGHT...AND MID 30S TO NEAR
40 THURSDAY AND FRIDAY NIGHTS.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL CONTINUE THROUGH THE DAY TODAY...LOWERING TO
MVFR LATER THIS EVENING AS STRATUS WORKS IN FROM THE SOUTH.
A VARIABLE WIND WILL BECOME SOUTH AROUND 10KTS LATER THIS
AFTERNOON OR EARLY EVENING.
A SYSTEM WILL BRING THE CLOUDS THIS EVENING AND SOME SCATTERED
RAIN SHOWERS...POSSIBLY MIXING WITH SNOW FLAKES LATER TOWARD
DAYBREAK. FOR NOW...WE WILL ONLY WENT VCSH INTO EARLY SUNDAY.
A FRONT WILL PASS THROUGH SHIFTING THE WIND TO THE WEST AROUND
10KTS WITH GUSTS TO 20KTS AT KPSF AND KALB. CONDITIONS WILL RETURN
TO VFR WITH GOOD VISIBILITY AT THE TAF SITES SUNDAY.
OUTLOOK...
SUNDAY NIGHT-THANKSGIVING DAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A FRONTAL SYSTEM WILL BRING SOME SHOWERS OF RAIN AND SNOW TONIGHT...
HEAVIEST ACROSS THE ADIRONDACKS WHERE A COUPLE INCHES OF SNOW
COULD ACCUMULATE. OTHERWISE...RAIN SHOWER AMOUNTS WILL BE
VERY LIGHT...WELL UNDER A QUARTER INCH MOST PLACES.
ASIDE FROM ON GOING SNOW SHOWERS ACROSS THE ADIRONDACKS...
THE REMAINDER OF THE REGION LOOKS MAINLY DRY SUNDAY THROUGH
THANKSGIVING DAY. EACH NIGHT WILL SEE A NEAR RECOVERY
OF RR VALUES...DROPPING TO SEASONABLE LEVELS IN THE 40S AND
50S EACH AFTERNOON. AMOUNTS WILL BE HIGHER ACROSS THE ADIRONDACKS
WHERE THERE WILL BE POSSIBLE PRECIPITATION...GENERALLY
IN THE 50S AND EVEN 60S.
IT WILL BE SOMEWHAT BREEZY ON SUNDAY...WITH A WESTERLY
WIND 10-15 MPH WITH GUSTS TO 25 MPH ACROSS THE HIGHER
TERRAIN/MOHAWK VALLEY AND CAPITAL REGION.
THE WIND WILL GENERALLY BE LIGHTER THROUGH THE REMAINDER OF THE WEEK.
THE NEXT CHANCE OF WIDESPREAD PRECIPITATION AFTER TONIGHT DOES NOT
APPEAR TO BE UNTIL LATE FRIDAY OR SATURDAY.
&&
.HYDROLOGY...
NO HYDROLOGY ISSUES ARE EXPECTED THROUGH THE NEXT WEEK. OTHER THAN
THE POTENTIAL FOR SCATTERED SHOWERS TONIGHT AND LAKE
ENHANCED SNOW SHOWERS IN HAMILTON AND HERKIMER COUNTIES SUNDAY...THE
PERIOD WILL BE MAINLY DRY THROUGH FRIDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...IRL
AVIATION...HWJIV
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
338 PM EST SAT NOV 21 2015
.SYNOPSIS...
LOW PRESSURE LOCATED OVER WESTERN OHIO THIS AFTERNOON WILL
PROGRESS NORTHEASTWARD AND INTO QUEBEC ON SUNDAY. THE LOW IS
FORECAST TO PULL A COLD FRONT THROUGH OUR AREA LATE TONIGHT. HIGH
PRESSURE SHOULD NOSE INTO OUR REGION FROM THE SOUTHWEST FOR SUNDAY
INTO MONDAY. THE HIGH IS EXPECTED TO BE LOCATED OVER THE
SOUTHEASTERN STATES ON MONDAY NIGHT. THE CENTER OF THE AIR MASS IS
ANTICIPATED TO MOVE NORTHEASTWARD AND IT SHOULD REACH CANADA`S
MARITIME PROVINCES ON WEDNESDAY. THE HIGH SHOULD CONTINUE TO
INFLUENCE OUR WEATHER INTO FRIDAY. A COLD FRONT APPROACHING FROM
THE NORTHWEST IS FORECAST TO ARRIVE ON SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AT LATE-DAY AN AREA OF HIGH PRESSURE WAS PULLING AWAY FROM OUR
REGION TO THE NORTHEAST AS STRENGTHENING LOW PRESSURE WAS TRACKING
FROM THE UPPER OHIO VALLEY TOWARD THE EASTERN GREAT LAKES. A COLD
FRONT EXTENDED DOWN FROM THE OHIO VALLEY AND INTO THE SOUTHEAST
STATES. THIS BOUNDARY WILL BE APPROACHING OUR AREA LATER TONIGHT,
AND CLOUDS WILL CONTINUE TO THICKEN AND LOWER THROUGH THIS
EVENING. NAM/GFS DATA AS WELL AS THE HRRR AND RAP OVERALL SHOW
DISORGANIZED, WIDELY SCATTERED SHOWERS ASSOCIATED WITH THE FRONT,
MAINLY AFTER MIDNIGHT, AS IT SWEEPS WEST TO EAST ACROSS THE
FORECAST AREA. THE SPEED OF THE FRONT THROUGH THE AREA AND
SOMEWHAT LIMITED MOISTURE ASSOCIATED WITH IT WILL LIMIT OVERALL
PRECIP CHANCES AND AMOUNTS. CURRENT MODEL GUIDANCE CONTINUES TO
FOCUS A BETTER CHANCE FOR SHOWERS FOR THE NORTHERN THIRD OF THE
FORECAST AREA INTO THE POCONOS, LEHIGH VALLEY, AND NORTHERN NEW
JERSEY, AND WE HAVE KEPT LOW CHANCE POPS FOR THESE AREAS, WITH
MAINLY SLIGHT CHANCE ELSEWHERE. IN ADDITION, THERE IS THE
POSSIBILITY FOR SOME WET SNOW TO MIX IN WITH THE RAIN SHOWERS
ACROSS THE FAR NORTH BEFORE THE PRECIP ENDS DEPENDING ON HOW
QUICKLY THE COLDER AIR ARRIVES BEHIND THE PASSING FRONT. OVERALL
QPF AMOUNTS WITH THIS FRONT WILL BE LIGHT, WITH ONLY A FEW
HUNDREDTHS OF AN INCH ANTICIPATED. MINIMUM TEMPERATURES ARE
EXPECTED TO RANGE MOSTLY FROM THE LOWER 40S SOUTH TO THE MIDDLE
30S NORTH, WITH PERHAPS THE HIGHER TERRAIN IN THE POCONOS DROPPING
INTO THE LOWER 30S.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
THE PREVIOUSLY MENTIONED COLD FRONT WILL BE TO OUR EAST AND
OFFSHORE INTO SUNDAY MORNING AS AN AREA OF LOW PRESSURE DEVELOPS
ALONG THE BOUNDARY WELL TO OUR SOUTH, OFF THE COAST OF THE
CAROLINAS. THIS LOW IS FORECAST TO REMAIN OFFSHORE AS IT
PROGRESSES FARTHER NORTHEAST AND OUT TO SEA LATER SUNDAY TO SUNDAY
EVENING. WHILE WE ARE EXPECTING THINNING CLOUDS AND CLEARING
CONDITIONS FOR MUCH OF THE FORECAST AREA DURING THE MORNING,
CLOUDS AND A FEW SHOWERS MAY HANG ON AT THE COAST THROUGH ABOUT
MIDDAY OR SO AS SOME MOISTURE GETS DRAWN NORTHWARD IN THE
SOUTHWEST FLOW ALOFT AHEAD OF THE LOW PRESSURE. OVERALL, WE KEPT
CHANCE POPS IN PLACE THROUGH THE MORNING AT THE COAST AND FOR OUR
COASTAL WATERS.
IN TERMS OF TEMPERATURES AND WINDS, SOME OF THE COOLEST AIR OF
THE AUTUMN SEASON THUS FAR WILL BEGIN SPREADING ACROSS THE REGION
ON GUSTY NORTHWESTERLY WINDS, GUSTING AT TIMES TO AROUND 25 MPH.
WE MOSTLY TOOK A BLEND OF MET/MAV GUIDANCE WITH CONTINUITY FOR
MAXIMUM TEMPERATURES, AND WE EXPECT HIGHS TO MAINLY BE IN THE
UPPER 40S TO LOWER 50S ACROSS THE REGION, WITH ONLY LOWER 40S
EXPECTED INTO THE POCONOS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE COLD FRONT WILL CONTINUE TO MOVE FARTHER OUT TO SEA ON SUNDAY
NIGHT WITH A ROBUST LOW FORECAST TO DEVELOP ALONG THE BOUNDARY.
THE THE MODEL GUIDANCE CONTINUES TO KEEP THE LOW WELL TO OUR EAST.
THE CIRRUS SHIELD ASSOCIATED WITH THE SYSTEM SHOULD BE OVERHEAD ON
SUNDAY EVENING BEFORE MOVING TO OUR EAST LATE ON SUNDAY NIGHT.
A MID LEVEL SHORT WAVE TROUGH APPROACHING FROM THE WEST IS
FORECAST TO PASS OVERHEAD ON MONDAY MORNING. THE COLDEST AIR OF
THE NEW WEEK IS EXPECTED TO ARRIVE IN ITS WAKE FOR MONDAY.
ANOTHER MID LEVEL SHORT WAVE TROUGH FROM THE NORTHWEST IS
ANTICIPATED TO PASS OVER OUR REGION LATE ON MONDAY NIGHT. THE
FEATURE IS EXPECTED TO BE PRECEDED BY SOME MID LEVEL CLOUDS ON
MONDAY EVENING. IT MAY BE ACCOMPANIED AND FOLLOWED BY SOME
STRATOCUMULUS OVER OUR NORTHERN COUNTIES ON MONDAY NIGHT.
A MID LEVEL RIDGE IS FORECAST TO BUILD OVER THE EASTERN STATES
AND THE WESTERN NORTH ATLANTIC DURING THE BALANCE OF THE NEW WEEK.
SURFACE HIGH PRESSURE IS EXPECTED TO MOVE FROM THE SOUTHEASTERN
STATES ON MONDAY NIGHT TO CANADA`S MARITIME PROVINCES ON
WEDNESDAY. A TRAILING SURFACE RIDGE IS FORECAST TO EXTEND INTO OUR
REGION INTO FRIDAY.
WE ARE ANTICIPATING DRY WEATHER FOR THE COMING WEEK. TEMPERATURES
WILL BEGIN ABOUT 10 DEGREES BELOW NORMAL ON MONDAY BUT THEY SHOULD
REBOUND TO AROUND 6 TO 8 DEGREES ABOVE NORMAL FOR THANKSGIVING DAY
AND FRIDAY.
A COLD FRONT IS EXPECTED TO APPROACH FROM THE NORTHWEST ON FRIDAY
NIGHT AND IT SHOULD PASS THROUGH OUR REGION ON SATURDAY. WE WILL
INDICATE A CHANCE OF RAIN SHOWERS AT THAT TIME.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...MAINLY VFR CONDITIONS ARE EXPECTED TO CONTINUE THIS
EVENING AND OVERNIGHT. A COLD FRONT WILL APPROACH THE REGION FROM
THE WEST THIS EVENING, AND WE WILL SEE A GRADUAL THICKENING AND
LOWERING OF VFR CLOUDS. WINDS THROUGH THIS EVENING WILL BE OUT OF
THE EAST-SOUTHEAST AND MAINLY IN THE 5 TO 8 KNOT RANGE. THE COLD
FRONT IS EXPECTED TO SWEEP ACROSS THE AREA BETWEEN ABOUT 07Z TO
12Z, AND AS THE FRONT PASSES THROUGH, WINDS WILL BECOME MORE
WESTERLY TO WEST-NORTHWEST AND INCREASE SOME UP TOWARD 10 TO 12
KNOTS. IN ADDITION WITH THE PASSAGE OF THE FRONT THROUGH THE
OVERNIGHT TO EARLY MORNING, CEILINGS WILL LOWER TOWARD ABOUT 3500
TO 4000 FEET WITH ISOLATED SHOWERS POSSIBLE, BUT AT THIS TIME, WE
DO NOT EXPECT ANY EXTENDED TIME OF SUB-VFR CONDITIONS. SHOWERS
WERE NOT INCLUDED IN THE TAFS AS THEY WILL BE BRIEF AND ISOLATED
IN NATURE.
SUNDAY...VFR CONDITIONS ARE EXPECTED BEHIND THE COLD FRONT WITH
CLOUDS THINNING. NORTHWESTERLY WINDS WILL BECOME GUSTY FOR MOST
SITES IN THE 12Z TO 14Z TIME FRAME AND CONTINUE THROUGH THE BULK
OF THE DAY. GUSTS INTO THE 20 TO 25 KNOT RANGE ARE EXPECTED.
OUTLOOK...
SUNDAY NIGHT THROUGH WEDNESDAY...MAINLY VFR.
WEDNESDAY NIGHT AND THURSDAY...MAINLY VFR. HOWEVER, PATCHY LATE
NIGHT AND EARLY MORNING FOG IS POSSIBLE.
&&
.MARINE...
A COLD FRONT WILL BE CROSSING THE AREA DURING THE OVERNIGHT TO
EARLY MORNING SUNDAY. AS THE FRONT PASSES, WINDS WILL SHIFT FROM
THE SOUTHEAST TO WESTERLY AND THEN NORTHWESTERLY DURING THE
DAYTIME SUNDAY. IN ADDITION, GUSTS WILL ALSO PICK UP BEHIND THE
FRONT, WITH GUSTS AROUND 25 KNOTS PLUS BEGINNING AROUND DAYBREAK
SUNDAY. SEAS WILL ALSO RESPOND WILL SOME 4 TO 5 FOOT SEAS FOR THE
ATLANTIC COASTAL WATERS AND 2 TO 4 FOOT SEAS INTO DELAWARE BAY. WE
HAVE RAISED A SMALL CRAFT ADVISORY FOR OUR COASTAL WATERS AND
DELAWARE BAY BEGINNING 11Z SUNDAY.
OUTLOOK...
SUNDAY NIGHT...A SMALL CRAFT ADVISORY IS IN EFFECT FOR NORTHWEST
WINDS GUSTING TO 25 TO 30 KNOTS.
MONDAY...THE SMALL CRAFT ADVISORY MAY NEED TO BE EXTENDED IN TIME
AS 25 KNOT WIND GUSTS FROM THE NORTHWEST MAY LINGER INTO AT LEAST
PART OF MONDAY.
MONDAY NIGHT THROUGH THURSDAY...NO MARINE HEADLINES ARE
ANTICIPATED.
&&
.TIDES/COASTAL FLOODING...
A DEVELOPING ONSHORE FLOW ALONG WITH THE HIGH ASTRONOMICAL TIDES
ASSOCIATED WITH THE UPCOMING FULL MOON MAY RESULT IN SOME MINOR
COASTAL FLOODING DURING THE SECOND HALF OF THE WEEK. THE MORNING
HIGH TIDE CYCLES ON THURSDAY AND FRIDAY SEEM MOST SUSCEPTIBLE.
POSITIVE DEPARTURES OF ONLY 0.3 TO 0.6 FEET ARE NEEDED FOR MINOR
FLOODING TO BEGIN.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM SUNDAY TO 6 AM EST MONDAY FOR
ANZ430-431-450>455.
&&
$$
SYNOPSIS...IOVINO
NEAR TERM...KLINE
SHORT TERM...KLINE
LONG TERM...IOVINO
AVIATION...IOVINO/KLINE
MARINE...IOVINO/KLINE
TIDES/COASTAL FLOODING...IOVINO
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1015 AM EST SAT NOV 21 2015
...INCREASED RAIN CHANCES THROUGH THIS WEEKEND FOLLOWED BY THE
COOLEST AIR OF THE DRY SEASON THUS FAR...
...HAZARDOUS BOATING CONDITIONS DEVELOPING SUNDAY AND CONTINUING
MOST OF NEXT WEEK...
.UPDATE...
CURRENT...SRLY COMPONENT TO METAR/C-MAN DATA OVER/OFFSHORE PB COUNTY
AND GRAND BAHAMA ISLAND PLACE THE DIFFUSE FRONTAL BDRY (A WARM FRONT
FOR THE TIME BEING) SOMEWHERE NORTH OF JUPITER INLET THIS MORNING.
IT`S PROBABLY OVER NORTH LAKE OKEECHOBEE...BUT BASED ON RADAR HAS
LIKELY LIFTED FARTHER NORTH OVER THE ATLC TO OFFSHORE BREVARD CO.
BDRY ALSO EXTENDS WELL WEST INTO THE GOMEX TO A WEAK LOW PRES WAVE
NEAR/ALONG 92W. WIDESPREAD MULTILAYERED CLOUDS ARE IN PLACE OVER THE
PENINSULA.
MORNING RAOBS SHOW RATHER UNIMPRESSIVE PWAT AT KXMR A LITTLE UNDER
1.5" WHILE DEEPER MEAN MOISTURE LURKS TO THE SOUTH (MFL 1.93") AND
WEST (TBW 1.76"). WATER VAPOR AND RUC MID-UPPER ANLYS FIELDS SHOW
VORTLOBES STUNG OUT ACROSS THE CENTRAL-ERN GOMEX WITH THE LEAD ONE
PUSHING INTO SE FL NEAR PGD/FMY. IMPRESSIVE SRN STREAM 80-90KT H25
JETSTREAK EXTENDS FROM THE GULF ACROSS NORTH FL WITH EXPANSIVE SWATH
OF DIVG OVHD.
REMAINDER OF TODAY...ELEMENTS LOOK TO BE IN PLACE FOR INCREASING CHC
OF RAIN OVER MUCH OF THE AREA AS INCREASING MOISTURE AND DEEP LAYER
FORCED ASCENT BEGIN TO SPREAD EAST AND OVHD THROUGH LATER TODAY.
LOCAL HRRR MODEL GUIDANCE SHOWS A GENEROUS COVERAGE A STRATIFORM
RAIN WITH EMBEDDED CONVECTION WILL DEVELOP BY LATE AFTERNOON AND
CONTINUE WELL INTO THIS EVENING. WHILE THIS MAY BE A TAD OVERDONE
MAV GUIDANCE PAINTS 50-60 POPS FOR TODAY WITH THE MET (60-80) AND
LAV (30-40) ON OPPOSITE SIDES. CURRENT GRIDS SHOW 50...WHICH SEEMS
LIKE A DECENT COMPROMISE GIVEN CURRENT RADAR AND SATELLITE TRENDS.
THINK CHC FOR THUNDER WILL BE QUITE LOW DUE TO ANTICIPATED LACK OF
INSOLATION...BUT NON-ZERO AS IT WILL BE OFFSET TO SOME DEGREE BY
COOLING ALOFT AND SLOWLY STRENGTHENING MEAN VV. ADDITIONALLY...WE
ALREADY HAD ISOLD EMBEDDED THUNDER WITH CELLS ALONG THE TREASURE
COAST AND WELL OFFSHORE BREVARD...SO EXPECT MORE OF THE SAME WITH
MODEST DAYTIME HEATING THROUGH THIS AFTERNOON.
GIVEN EXPECTED CLOUD COVER...NUDGED MAX TEMPS DOWN BY A DEGREE OR
SO...RESULTING IN ALL AREAS REACHING THE U70S TO AROUND 80F OR SO.
&&
.AVIATION...WIDESPREAD VFR OVC-BKN150 WITH LCL-AREAS MVFR BKN CIGS
IN CONVECTIVE CU...INCREASING IN COVERAGE AFT 18Z. LCL IFR VSBYS IN
+SHRA/TS...BUT GREATER COVERAGE OF MVFR VSBYS/CIGS IN PRECIP SHOULD
BECOME MORE PREVALENT.
&&
.MARINE...WARM FRONT MOVING NWD INTO THE MAOR HAS PUT A DENT IN THE
SFC PGRAD. AS A RESULT WINDS ARE 20KT OR LESS WITH SEAS 3-4FT NEAR
SHORE AND 5 TO OCNL 6FT WELL AWAY FROM THE COAST. CURRENT FORECAST
WITH SCEC 20-60NM OFFSHORE NORTH OF SEBASTIAN INLET IS SPOT ON. NO
CHGS NEEDED.
&&
UPDATE/SHORT TERM/AVIATION...CRISTALDI
LONG TERM/IMPACT WX/DSS....BLOTTMAN
&&
.PREV DISCUSSION... /ISSUED 348 AM EST SAT NOV 21 2015/
TONIGHT...SOME OF THE DAYTIME CONVECTION MAY LINGER INTO EVENING...
BUT THE GREATEST LARGE SCALE ASCENT AHEAD OF THE SHORTWAVE WILL BE
AFTER MIDNIGHT. MOS POPS ARE VERY HIGH TONIGHT...75-90 PERCENT...
WHICH LOOKS REASONABLE GIVEN THE IMPRESSIVE DIVERGENCE ALOFT WHICH
IS DEPICTED BY THE GFS. HOWEVER THE BULK OF THIS PRECIP SHOULD BE
QUITE LATE... SO HAVE KEPT OUR PREVIOUS FORECAST FOR AREAWIDE 70
PERCENT CHANCES. WILL ALSO KEEP MENTION OF SLIGHT CHANCE FOR STORMS
OVERNIGHT DUE TO LARGE SCALE ASCENT AND WEAK ELEVATED INSTABILITY.
SUN...AN AMORPHOUS AREA OF LOW PRESSURE WILL STRETCH FROM OFF THE
SOUTHWEST COAST OF FLORIDA TOWARD THE ATLANTIC WATERS OFFSHORE
GEORGIA/SOUTH CAROLINA. THE LOW WILL ORGANIZE NORTH OF THE BAHAMAS
BEFORE ADVANCING QUICKLY TO THE NORTH AND EAST. AS IT DOES SO...A
STRONG COLD FRONT WILL ADVANCE OVER THE AREA LATE SUNDAY INTO EARLY
MONDAY.
LARGE SCALE ASCENT ALOFT WILL BE ONGOING THROUGH THE MORNING AS LOW
LEVEL CONVERGENCE IN ASSOCIATION WITH THE WEAK LOW SHIFTS TOWARDS
THE CENTRAL/SOUTHERN PENINSULA. EXPECT SHOWER COVERAGE TO BE
WIDESPREAD THROUGH AT LEAST THE FIRST HALF OF THE DAY. AS THE SYSTEM
PULLS AWAY LATE SUNDAY...RAIN CHANCES WILL LOWER AND ABATE FROM
NORTH TO SOUTH. CLOUDS WILL HOLD MAXES DOWN ON SUNDAY WHILE COLD AIR
ADVECTION BEGINS IN EARNEST SUNDAY NIGHT. EXPECTING A LARGE SPREAD
IN MINS...UPPER 40S ACROSS THE FAR NORTH AND 60-65 ALONG THE
TREASURE COAST. CONSIDERING THE VERY WARM TEMPERATURES THUS FAR THIS
FALL...AND THE FACT THAT WINDS ARE EXPECTED TO REMAIN BREEZY THROUGH
THE OVERNIGHT AND INTO EARLY MONDAY MORNING...IT WILL FEEL QUITE
CHILLY AS YOU HEAD OUT THE DOOR.
MON-FRI...COLD FRONT WILL BE WELL SOUTH OF THE AREA BY SUNRISE
MONDAY AS NORTHWEST WINDS USHER IN THE COOLEST AIR OF THE SEASON.
MAX HIGHS WILL STRUGGLE TO ESCAPE THE 60S DURING THE DAY ON MONDAY.
AS HAS BEEN THE CASE WITH NEARLY EVERY FROPA THIS SEASON...POST-
FRONTAL WINDS WILL RAPIDLY VEER ONSHORE...MODIFYING THE AIR MASS FOR
THE COASTAL COUNTIES AS EARLY AS MONDAY NIGHT. THIS WILL BE MOST
PRONOUNCED ALONG THE TREASURE COAST GIVEN THE STILL-WARM SHELF WATER
TEMPS THERE.
AS FLOW VEERS ONSHORE LATE MONDAY INTO TUESDAY...WILL LIKELY SEE
SIGNIFICANT MARINE STRATOCU FORM OVER THE ATLANTIC AND SPREAD
INLAND. BRIEF LIGHT RAIN / SPRINKLES POSSIBLE TUESDAY (CONFINED TO
THE COASTAL WATERS IN THIS FORECAST PACKAGE) BEFORE ONSHORE MOVING
SHOWERS RE-ENTER THE PICTURE MID-WEEK AND BEYOND AS MOISTURE
INCREASES IN DEEPENING EAST FLOW. MEANWHILE...TEMPS CLIMB TO NEAR
CLIMO BY WEDNESDAY AND ABOVE THU-FRI.
&&
.AVIATION...
CONDITIONS SO FAR THIS MORNING HAVE MAINLY BEEN VFR EXCEPT FOR A
FEW BRIEF MVFR CEILINGS. EXPECT THIS TREND TO CONTINUE...THEN AS
DAYTIME HEATING CLOUDS FORM...MORE AREAS OF MVFR CEILINGS SHOULD
FORM. SCATTERED SHOWERS AND A FEW STORMS ARE FORECAST DURING THE
AFTERNOON AND EARLY EVENING. A HIGHER COVERAGE OF SHOWERS AND
ISOLATED STORMS SHOULD SPREAD INLAND FROM THE GULF IN THE PRE
DAWN HOURS OF SUNDAY.
&&
.MARINE...
TODAY-TONIGHT...EAST WINDS WILL GRADUALLY VEER TO SOUTHEAST AND
EVEN SOUTH LATE IN THE DAY AS OLD FRONTAL TROUGH LIFTS BACK INTO
THE WATERS. SPEEDS LOOK TO BE 10-15 KNOTS EARLY THIS MORNING AND
EASING TO 10 KNOTS OR LESS THIS AFTERNOON. HAVE CANCELLED THE
SMALL CRAFT ADVISORY AS TIGHTENED PRESSURE GRADIENT WAS BRIEF OVER
OUR NORTHERN WATERS. EXPECT SCATTERED MAINLY AFTERNOON SHOWERS
WITH A SLIGHT CHANCE OF STORMS THROUGH EARLY EVENING. A HIGHER
COVERAGE OF SHOWERS WILL OCCUR IN THE PRE DAWN HOURS OF SUNDAY.
SUN-WED...PRESSURE GRADIENT WILL START OFF RELAXED EARLY SUNDAY
BEFORE TIGHTENING AS LOW PRESSURE ORGANIZES NORTH OF THE BAHAMAS. AS
THE LOW PULLS AWAY TO THE NORTH AND EAST...A STRONG COLD FRONT WILL
MOVE ACROSS THE COASTAL WATERS LATE SUNDAY. STRONG SUSTAINED
NORTHERLY WINDS OF AROUND 25 KNOTS WILL BUILD SEAS BEHIND THE
FRONT...RESULTING IN A QUICK TRANSITION TO HAZARDOUS BOATING/SURF
CONDITIONS THAT WILL LINGER THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK. EXPECT HIGH END SCA CONDITIONS WITH GUSTS NEAR GALE
FORCE...AND SEAS AS HIGH AS 12-13FT IN THE GULF STREAM...PERHAPS
BRIEFLY HIGHER. WE ALSO MAY BE LOOKING AS DANGEROUS BEACH CONDITIONS
EARLY NEXT WEEK WITH HIGH/CHOPPY SURF AND STRONG RIPS WITH POTENTIAL
FOR ADVISORY CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 81 67 69 50 / 50 70 70 30
MCO 84 68 72 52 / 50 70 70 40
MLB 83 69 73 61 / 50 70 70 40
VRB 84 69 75 64 / 50 70 70 40
LEE 82 67 69 47 / 50 70 70 30
SFB 82 67 72 51 / 50 70 70 40
ORL 83 68 71 51 / 50 70 70 40
FPR 84 69 76 64 / 50 70 70 50
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
348 AM EST SAT NOV 21 2015
.DISCUSSION...
...INCREASED RAIN CHANCES THIS WEEKEND...
...HAZARDOUS BOATING CONDITIONS DEVELOPING SUNDAY AND CONTINUING
MOST OF NEXT WEEK...
TODAY-TONIGHT...HIGH MOISTURE BAND VICINITY OF OLD FRONT WAS OVER
SOUTH FLORIDA AND INTO THE GULF OF MEXICO. SHORTWAVE TROUGH WILL
MOVE THROUGH THE MID PART OF THE COUNTRY AND INDUCE A WEAK WAVE OF
LOW PRESSURE ALONG THE BOUNDARY IN THE GULF. THIS WILL ALLOW THE
BOUNDARY AND ASSOCIATED HIGH MOISTURE TO LIFT A LITTLE NORTHWARD.
THOUGH WE WILL HAVE CONSIDERABLE HIGH LEVEL CLOUDINESS TO START
OFF THE DAY...EXPECT A LITTLE HEATING AND WITH 500 MB TEMPS AROUND
MINUS 9 CELSIUS...SUFFICIENT INSTABILITY WILL EXIST FOR ISOLATED
LIGHTNING STORMS.
THE HRRR MODEL HOURLY RUNS HAVE RANGED FROM EARLY CONVECTION
ALONG REMNANT OLD FRONTAL BOUNDARY IN THE SOUTH...TO MORE RECENTLY
HIGHLIGHTING NORTHERN AREAS WITH THE MOST CONVECTION AS EAST COAST
SEA BREEZE MOVES INLAND. EARLY MORNING RADAR HAS NOT BEEN SHOWING
MUCH SHOWER ACTIVITY OVER THE ATLANTIC AND WITH LIMITED DIRECT
SOLAR INSOLATION TODAY...PREFER NOT TO GO WITH LIKELY POPS.
INSTEAD WILL GO 50 PERCENT EVERYWHERE...WHICH IS WHAT THE 00Z MOS
VALUES WERE.
SOME OF THE DAYTIME CONVECTION MAY LINGER INTO EVENING...BUT THE
GREATEST LARGE SCALE ASCENT AHEAD OF THE SHORTWAVE WILL BE AFTER
MIDNIGHT. MOS POPS ARE VERY HIGH TONIGHT...75-90 PERCENT...WHICH
LOOKS REASONABLE GIVEN THE IMPRESSIVE DIVERGENCE ALOFT DEPICTED BY
THE GFS. HOWEVER THE BULK OF THIS PRECIP SHOULD BE QUITE LATE...
SO HAVE KEPT OUR PREVIOUS FORECAST FOR AREAWIDE 70 PERCENT
CHANCES. WILL ALSO KEEP MENTION OF SLIGHT CHANCE FOR STORMS
OVERNIGHT DUE TO LARGE SCALE ASCENT AND WEAK ELEVATED INSTABILITY.
SUN...AN AMORPHOUS AREA OF LOW PRESSURE WILL STRETCH FROM OFF THE
SOUTHWEST COAST OF FLORIDA TOWARD THE ATLANTIC WATERS OFFSHORE
GEORGIA/SOUTH CAROLINA. THE LOW WILL ORGANIZE NORTH OF THE BAHAMAS
BEFORE ADVANCING QUICKLY TO THE NORTH AND EAST. AS IT DOES SO...A
STRONG COLD FRONT WILL ADVANCE OVER THE AREA LATE SUNDAY INTO EARLY
MONDAY.
LARGE SCALE ASCENT ALOFT WILL BE ONGOING THROUGH THE MORNING AS LOW
LEVEL CONVERGENCE IN ASSOCIATION WITH THE WEAK LOW SHIFTS TOWARDS
THE CENTRAL/SOUTHERN PENINSULA. EXPECT SHOWER COVERAGE TO BE
WIDESPREAD THROUGH AT LEAST THE FIRST HALF OF THE DAY. AS THE SYSTEM
PULLS AWAY LATE SUNDAY...RAIN CHANCES WILL LOWER AND ABATE FROM
NORTH TO SOUTH. CLOUDS WILL HOLD MAXES DOWN ON SUNDAY WHILE COLD AIR
ADVECTION BEGINS IN EARNEST SUNDAY NIGHT. EXPECTING A LARGE SPREAD
IN MINS...UPPER 40S ACROSS THE FAR NORTH AND 60-65 ALONG THE
TREASURE COAST. CONSIDERING THE VERY WARM TEMPERATURES THUS FAR THIS
FALL...AND THE FACT THAT WINDS ARE EXPECTED TO REMAIN BREEZY THROUGH
THE OVERNIGHT AND INTO EARLY MONDAY MORNING...IT WILL FEEL QUITE
CHILLY AS YOU HEAD OUT THE DOOR.
MON-FRI...COLD FRONT WILL BE WELL SOUTH OF THE AREA BY SUNRISE
MONDAY AS NORTHWEST WINDS USHER IN THE COOLEST AIR OF THE SEASON.
MAX HIGHS WILL STRUGGLE TO ESCAPE THE 60S DURING THE DAY ON MONDAY.
AS HAS BEEN THE CASE WITH NEARLY EVERY FROPA THIS SEASON...POST-
FRONTAL WINDS WILL RAPIDLY VEER ONSHORE...MODIFYING THE AIR MASS FOR
THE COASTAL COUNTIES AS EARLY AS MONDAY NIGHT. THIS WILL BE MOST
PRONOUNCED ALONG THE TREASURE COAST GIVEN THE STILL-WARM SHELF WATER
TEMPS THERE.
AS FLOW VEERS ONSHORE LATE MONDAY INTO TUESDAY...WILL LIKELY SEE
SIGNIFICANT MARINE STRATOCU FORM OVER THE ATLANTIC AND SPREAD
INLAND. BRIEF LIGHT RAIN / SPRINKLES POSSIBLE TUESDAY (CONFINED TO
THE COASTAL WATERS IN THIS FORECAST PACKAGE) BEFORE ONSHORE MOVING
SHOWERS RE-ENTER THE PICTURE MID-WEEK AND BEYOND AS MOISTURE
INCREASES IN DEEPENING EAST FLOW. MEANWHILE...TEMPS CLIMB TO NEAR
CLIMO BY WEDNESDAY AND ABOVE THU-FRI.
&&
.AVIATION...
CONDITIONS SO FAR THIS MORNING HAVE MAINLY BEEN VFR EXCEPT FOR A
FEW BRIEF MVFR CEILINGS. EXPECT THIS TREND TO CONTINUE...THEN AS
DAYTIME HEATING CLOUDS FORM...MORE AREAS OF MVFR CEILINGS SHOULD
FORM. SCATTERED SHOWERS AND A FEW STORMS ARE FORECAST DURING THE
AFTERNOON AND EARLY EVENING. A HIGHER COVERAGE OF SHOWERS AND
ISOLATED STORMS SHOULD SPREAD INLAND FROM THE GULF IN THE PRE
DAWN HOURS OF SUNDAY.
&&
.MARINE...
TODAY-TONIGHT...EAST WINDS WILL GRADUALLY VEER TO SOUTHEAST AND
EVEN SOUTH LATE IN THE DAY AS OLD FRONTAL TROUGH LIFTS BACK INTO
THE WATERS. SPEEDS LOOK TO BE 10-15 KNOTS EARLY THIS MORNING AND
EASING TO 10 KNOTS OR LESS THIS AFTERNOON. HAVE CANCELLED THE
SMALL CRAFT ADVISORY AS TIGHTENED PRESSURE GRADIENT WAS BRIEF OVER
OUR NORTHERN WATERS. EXPECT SCATTERED MAINLY AFTERNOON SHOWERS
WITH A SLIGHT CHANCE OF STORMS THROUGH EARLY EVENING. A HIGHER
COVERAGE OF SHOWERS WILL OCCUR IN THE PRE DAWN HOURS OF SUNDAY.
SUN-WED...PRESSURE GRADIENT WILL START OFF RELAXED EARLY SUNDAY
BEFORE TIGHTENING AS LOW PRESSURE ORGANIZES NORTH OF THE BAHAMAS. AS
THE LOW PULLS AWAY TO THE NORTH AND EAST...A STRONG COLD FRONT WILL
MOVE ACROSS THE COASTAL WATERS LATE SUNDAY. STRONG SUSTAINED
NORTHERLY WINDS OF AROUND 25 KNOTS WILL BUILD SEAS BEHIND THE
FRONT...RESULTING IN A QUICK TRANSITION TO HAZARDOUS BOATING/SURF
CONDITIONS THAT WILL LINGER THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK. EXPECT HIGH END SCA CONDITIONS WITH GUSTS NEAR GALE
FORCE...AND SEAS AS HIGH AS 12-13FT IN THE GULF STREAM...PERHAPS
BRIEFLY HIGHER. WE ALSO MAY BE LOOKING AS DANGEROUS BEACH CONDITIONS
EARLY NEXT WEEK WITH HIGH/CHOPPY SURF AND STRONG RIPS WITH POTENTIAL
FOR ADVISORY CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 81 67 69 50 / 50 70 70 30
MCO 84 68 72 52 / 50 70 70 40
MLB 83 69 73 61 / 50 70 70 40
VRB 84 69 75 64 / 50 70 70 40
LEE 82 67 69 47 / 50 70 70 30
SFB 82 67 72 51 / 50 70 70 40
ORL 83 68 71 51 / 50 70 70 40
FPR 84 69 76 64 / 50 70 70 50
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...LASCODY
LONG TERM....ULRICH
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
255 PM CST SAT NOV 21 2015
.SHORT TERM...(Tonight)
ISSUED AT 255 PM CST SAT NOV 21 2015
20z/2pm surface analysis shows 1006mb low over west-central Ohio,
with light snow lingering westward across much of the KILX CWA. The
snow has ended and skies are beginning to clear west of the Illinois
River, and this clearing will work its way steadily eastward over
the next few hours. Satellite timing tools suggest the back edge of
the cloud shield will be along a Bloomington to Shelbyville line by
00z/6pm...then will be into Indiana by 04z/10pm. Skies will then be
clear across the board until late tonight when SCT-BKN mid-level
clouds associated with a short-wave trough spill into the W/SW CWA
toward dawn. Strong northwesterly winds gusting to between 20 and
30 mph early this evening will diminish to less than 10 mph and back
to the W/SW overnight. Thanks to the clear skies and diminishing
winds over a fresh snow-cover across the northern half of the CWA,
this will be the coldest night thus far this season. Lows will drop
into the teens in most areas, but will bottom out in the single
digits where the snow cover is deepest across Knox, Stark, and
Marshall counties.
&&
.LONG TERM...(Sunday through Saturday)
ISSUED AT 255 PM CST SAT NOV 21 2015
Cold air moving into the region overnight with clearing skies, and
by Sunday morning, temperatures will drop into the single digits and
teens. Brisk winds in the morning will result in wind chills
dropping to -5C to 11C range. Sundays high temperatures will
struggle into the 30s, with areas in the north and nearer to any
remaining snow will have a hard time reaching the freezing mark,
although southerly winds will assist to counter with some weak waa.
Southwesterly flow aloft assists the warm up with the next system
digging into the desert SW and amplifying the pattern across the
CONUS. Big question for the first part of the week will be how much
of the snow remains in the northern tier of the state. Have pulled
down the temps both Monday and Tuesday from the SuperBlend to
compensate for the influence of the snowpack. Elsewhere,
temperatures start on a warming trend that will continue through the
holiday. By Wednesday and Thursday, temps are above freezing through
the overnight as well and the next system lays out a boundary across
the region, providing a focus for plenty of rain in the Midwest in
time for holiday travel. So far the models are keeping rain
prolonged through Thanksgiving and into Friday. Disparity in the
operational models with respect to the timing/clearing out of the
wave. With ECMWF and the Canadian hinting at a kicker wave digging
in over the Pacific, inclined to point the forecast towards a more
rapid clearing. Cold air will move in again behind the system, with
chilly temperatures back for next weekend.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1218 PM CST SAT NOV 21 2015
IFR conditions will prevail at the central Illinois terminals for
the next few hours...before the low clouds/snow begin to clear the
area from west to east by mid to late afternoon. Latest satellite
imagery shows back edge of clouds currently along the Mississippi
River and advancing steadily eastward. Based on satellite timing
tools and HRRR forecasts...have ended the snow at KPIA by
20z...then further east to KCMI by 22z. Skies will clear at KPIA
by 22z...but will remain overcast further east at KCMI until
around 01z. Northwesterly winds will become strong/gusty this
afternoon through early evening. Current obs are already showing
gusts in the 25 to 30kt range and these will continue/spread
eastward through the remainder of the day. As low pressure lifts
further northeastward and the pressure gradient relaxes...the
gusts will subside by mid-evening. As high pressure
approaches...winds will become light and gradually back to the SW
late tonight into Sunday morning.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until 3 PM CST this afternoon for ILZ038-
043>046-055-057.
&&
$$
SHORT TERM...Barnes
LONG TERM...HJS
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1218 PM CST SAT NOV 21 2015
.UPDATE...
ISSUED AT 1043 AM CST SAT NOV 21 2015
16z/10am surface analysis shows 1012mb low between KDEC and KMTO.
Widespread precipitation is ongoing across all of central and
southeast Illinois, with the rain/snow line along/south of a
Taylorville to Robinson line. As the low shifts eastward into
Indiana, northwesterly winds will cool the atmosphere sufficiently
to support a rain/snow mix as far south as Olney/Lawrenceville
this afternoon. Light to moderate snow will continue across the
northern two-thirds of the KILX CWA through early afternoon before
the precip gradually ends from west to east. Latest satellite
imagery shows the back edge of the cloud/precip shield across
eastern Iowa/northern Missouri and this will advance steadily
eastward over the next few hours. Based on satellite timing tools
and HRRR forecast, have lingered PoPs across the E/NE CWA a bit
longer into the afternoon before ending all precip by 00z. Storm
total snowfall with this system is on track with previous
forecasts: however, have increased the amounts into the 6 to
8-inch range across Knox/Stark counties and have included amounts
of 1 inch or less as far south as a Springfield to Mattoon line.
&&
.SHORT TERM...(Today)
ISSUED AT 336 AM CST SAT NOV 21 2015
the 09z/3am surface analysis shows the center of the low pressure in
south-central Missouri, with a warm front extending across southern
IL, roughly along I-70. The rain-snow line has maintained farther
north...with snow remaining north of a line from Macomb to Peoria to
Pontiac. The Peoria airport just SW of Peoria has little to no snow,
while the north side of Peoria has what looks to be at least an inch
of snow, and possibly more, on grassy surfaces based on IDOT
cameras. Reports of 2.5" of snow have come in from Knox county
observers in Altona and Abingdon earlier tonight.
The RAP and HRRR take the surface low across southern IL, with
deformation band snows continuing in our NW counties. Cold air along
the northern edge of the system will gradually get pulled southward
into our counties, prompting the rain to change to snow
progressively farther south and east. Snowfall amounts look on track
for our NW counties to be in the 3 to 6 inch range, with a sharp
cutoff down to an inch or less. As the deformation band progresses
across central IL into the afternoon, our NE counties could see
snowfall amounts up to an inch or possibly a little more toward
Hoopeston. We did not expand the winter weather advisory eastward, as
snow amounts should remain enough below the 3" criteria for
Champaign and Vermilion counties. The southern row of counties of
our advisory (Fulton, Tazewell, McLean) will be borderline in terms
of snow amounts as well, but will continue with headlines unchanged
as there remains some uncertainty as to how soon the cold air will
surge southward to change rain to snow, and how efficient of
snowfall production will occur in our NW areas.
Temps will remain warm enough for rain south of I-72 for a majority
of the day, with any change to snow coming so late in the event
that little to no snow accumulation is expected south of there.
The center of the surface low is forecast to pull into Indiana by 11
am/17z, so cold air will invade on strong NW winds by early
afternoon. High temps will likely occur by Noon in most areas
because of that, with steady or falling temps this afternoon as
winds increase to 25-30 mph. The snow should generally be too wet to
blow around, but wind chills could drop into the teens in our W-NW
counties.
.LONG TERM...(Tonight through Friday)
ISSUED AT 336 AM CST SAT NOV 21 2015
Strong short wave to lift ne of central IL early this evening with
Canadian high pressure over the central Rockies quickly ridging east
into the mid MS river valley by dawn Sunday. Clouds to decrease from
west to east later this afternoon and into the evening while nw
winds 15-25 mph at sunset today diminish to 5-10 mph overnight.
Diminishing clouds and winds to bring a very cold night to the
area especially over northern CWA where snow cover where lows will
be 7- 13F with mid teens over central parts of CWA and upper teens
to near 20F in southeast IL. Wind chills will lower to 5 above to
5 below zero northern cwa and 10-15 southeast IL. This will be the
coldest night since March 6th over central IL. High pressure
ridges into the Ohio river valley by sunset Sunday while upper
level trof axis shifts east of IL. A mostly sunny but cold day
with highs ranging form lower 30s from i-74 ne, mid 30s central
CWA and upper 30s sw CWA. Winds to become ssw at 7-14 mph by
Sunday afternoon.
After a taste of winter weather this weekend for IL, temperatures to
moderate back above normal during the upcoming work week with upper
level heights rising over the region and nearly zonal upper level
flow Monday becoming sw by mid week with strong upper level ridge in
the east and strong upper level low/trof digging in the western
states. Dry weather expected Monday through Wednesday with temps
warming back up. Lows Sunday night in the mid to upper 20s. Highs
Monday range from lower 40s from I-74 ne where remaining snow cover
likely to melt while upper 40s to near 50F sw CWA. Highs by Wed in
the low to mid 50s and mid to upper 50s on Thanksgiving day. 00Z
models have trended slower with qpf returning to IL Wed night and
Thu and looks like a wet period from Wed night into early Sat. GFS
is quicker than ECMWF model with cold front moving through later Thu
night and Friday with highest pops will likely be. Between 1 and 2
inches of rain appear possible during this time frame. Rain chances
diminish next weekend and colder air returns to central/se IL.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1218 PM CST SAT NOV 21 2015
IFR conditions will prevail at the central Illinois terminals for
the next few hours...before the low clouds/snow begin to clear the
area from west to east by mid to late afternoon. Latest satellite
imagery shows back edge of clouds currently along the Mississippi
River and advancing steadily eastward. Based on satellite timing
tools and HRRR forecasts...have ended the snow at KPIA by
20z...then further east to KCMI by 22z. Skies will clear at KPIA
by 22z...but will remain overcast further east at KCMI until
around 01z. Northwesterly winds will become strong/gusty this
afternoon through early evening. Current obs are already showing
gusts in the 25 to 30kt range and these will continue/spread
eastward through the remainder of the day. As low pressure lifts
further northeastward and the pressure gradient relaxes...the
gusts will subside by mid-evening. As high pressure
approaches...winds will become light and gradually back to the SW
late tonight into Sunday morning.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until 3 PM CST this afternoon for ILZ038-
043>046-055-057.
&&
$$
UPDATE...Barnes
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1043 AM CST SAT NOV 21 2015
.UPDATE...
ISSUED AT 1043 AM CST SAT NOV 21 2015
16z/10am surface analysis shows 1012mb low between KDEC and KMTO.
Widespread precipitation is ongoing across all of central and
southeast Illinois, with the rain/snow line along/south of a
Taylorville to Robinson line. As the low shifts eastward into
Indiana, northwesterly winds will cool the atmosphere sufficiently
to support a rain/snow mix as far south as Olney/Lawrenceville
this afternoon. Light to moderate snow will continue across the
northern two-thirds of the KILX CWA through early afternoon before
the precip gradually ends from west to east. Latest satellite
imagery shows the back edge of the cloud/precip shield across
eastern Iowa/northern Missouri and this will advance steadily
eastward over the next few hours. Based on satellite timing tools
and HRRR forecast, have lingered PoPs across the E/NE CWA a bit
longer into the afternoon before ending all precip by 00z. Storm
total snowfall with this system is on track with previous
forecasts: however, have increased the amounts into the 6 to
8-inch range across Knox/Stark counties and have included amounts
of 1 inch or less as far south as a Springfield to Mattoon line.
&&
.SHORT TERM...(Today)
ISSUED AT 336 AM CST SAT NOV 21 2015
the 09z/3am surface analysis shows the center of the low pressure in
south-central Missouri, with a warm front extending across southern
IL, roughly along I-70. The rain-snow line has maintained farther
north...with snow remaining north of a line from Macomb to Peoria to
Pontiac. The Peoria airport just SW of Peoria has little to no snow,
while the north side of Peoria has what looks to be at least an inch
of snow, and possibly more, on grassy surfaces based on IDOT
cameras. Reports of 2.5" of snow have come in from Knox county
observers in Altona and Abingdon earlier tonight.
The RAP and HRRR take the surface low across southern IL, with
deformation band snows continuing in our NW counties. Cold air along
the northern edge of the system will gradually get pulled southward
into our counties, prompting the rain to change to snow
progressively farther south and east. Snowfall amounts look on track
for our NW counties to be in the 3 to 6 inch range, with a sharp
cutoff down to an inch or less. As the deformation band progresses
across central IL into the afternoon, our NE counties could see
snowfall amounts up to an inch or possibly a little more toward
Hoopeston. We did not expand the winter weather advisory eastward, as
snow amounts should remain enough below the 3" criteria for
Champaign and Vermilion counties. The southern row of counties of
our advisory (Fulton, Tazewell, McLean) will be borderline in terms
of snow amounts as well, but will continue with headlines unchanged
as there remains some uncertainty as to how soon the cold air will
surge southward to change rain to snow, and how efficient of
snowfall production will occur in our NW areas.
Temps will remain warm enough for rain south of I-72 for a majority
of the day, with any change to snow coming so late in the event
that little to no snow accumulation is expected south of there.
The center of the surface low is forecast to pull into Indiana by 11
am/17z, so cold air will invade on strong NW winds by early
afternoon. High temps will likely occur by Noon in most areas
because of that, with steady or falling temps this afternoon as
winds increase to 25-30 mph. The snow should generally be too wet to
blow around, but wind chills could drop into the teens in our W-NW
counties.
.LONG TERM...(Tonight through Friday)
ISSUED AT 336 AM CST SAT NOV 21 2015
Strong short wave to lift ne of central IL early this evening with
Canadian high pressure over the central Rockies quickly ridging east
into the mid MS river valley by dawn Sunday. Clouds to decrease from
west to east later this afternoon and into the evening while nw
winds 15-25 mph at sunset today diminish to 5-10 mph overnight.
Diminishing clouds and winds to bring a very cold night to the
area especially over northern CWA where snow cover where lows will
be 7- 13F with mid teens over central parts of CWA and upper teens
to near 20F in southeast IL. Wind chills will lower to 5 above to
5 below zero northern cwa and 10-15 southeast IL. This will be the
coldest night since March 6th over central IL. High pressure
ridges into the Ohio river valley by sunset Sunday while upper
level trof axis shifts east of IL. A mostly sunny but cold day
with highs ranging form lower 30s from i-74 ne, mid 30s central
CWA and upper 30s sw CWA. Winds to become ssw at 7-14 mph by
Sunday afternoon.
After a taste of winter weather this weekend for IL, temperatures to
moderate back above normal during the upcoming work week with upper
level heights rising over the region and nearly zonal upper level
flow Monday becoming sw by mid week with strong upper level ridge in
the east and strong upper level low/trof digging in the western
states. Dry weather expected Monday through Wednesday with temps
warming back up. Lows Sunday night in the mid to upper 20s. Highs
Monday range from lower 40s from I-74 ne where remaining snow cover
likely to melt while upper 40s to near 50F sw CWA. Highs by Wed in
the low to mid 50s and mid to upper 50s on Thanksgiving day. 00Z
models have trended slower with qpf returning to IL Wed night and
Thu and looks like a wet period from Wed night into early Sat. GFS
is quicker than ECMWF model with cold front moving through later Thu
night and Friday with highest pops will likely be. Between 1 and 2
inches of rain appear possible during this time frame. Rain chances
diminish next weekend and colder air returns to central/se IL.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
ISSUED AT 600 AM CST SAT NOV 21 2015
Conditions are expected to continue at IFR or LIFR for PIA and BMI
where snow will fall through the morning and into early afternoon.
IFR conditions will develop at SPI, DEC and CMI as the morning
progresses, as rain changes to snow. Low pressure will pass south
of the area this morning, roughly just south of I-70. The low will
move into Indiana before Noon/18z, causing winds to shift to the
NE, then N, then NW by afternoon for all TAF sites. Wind speeds
will increase to 15 to 20kt after 15z, with gusts to 30kt at times
this afternoon. Winds will diminish to 8-12kt after 00z.
Initially, surface temps will hover right around or just above
freezing early this morning for a few hours. Ground temperatures
are generally above freezing, so snow accumulation on travel
surfaces will remain lower than grassy areas. 1 inch of slushy
accumulation could occur at PIA, with less than an inch at BMI and
CMI, and little to no snow accumulation at DEC and SPI. IFR
conditions should gradually improve to MVFR during the afternoon
and then to VFR after 00-03z.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until noon CST today for ILZ027>031-
036>038.
&&
$$
UPDATE...Barnes
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1012 AM CST SAT NOV 21 2015
.UPDATE...
915 AM CST
ONLY CHANGE TO HEADLINES WAS TO UPGRADE ADVISORY TO A WINTER STORM
WARNING FOR LAKE AND PORTER COUNTIES IN NORTHWEST INDIANA.
MAJORITY OF FORECAST CONTINUES WELL ON TRACK...INCLUDING FOR THE
MOST PART SNOWFALL TOTALS AND ENDING TIMES TODAY.
THE WELL-DEFINED TROUGH ON SATELLITE THIS MORNING IS SWINGING
INTO THE AREA...PIVOTING SLIGHTLY MORE NEGATIVELY TILTED...WITH
RAPID MID-LEVEL AND DYNAMIC COOLING. AN IMPRESSIVE 500MB
TEMPERATURE DIFFERENCE FROM MPX TO DVN OF 16C HIGHLIGHTS THAT.
THE SURFACE TEMPERATURES ARE STARTING TO SLOWLY FALL IN NORTH
CENTRAL ILLINOIS WITH NORTHERLY WINDS. TEMPERATURES ARE ALSO
BEGINNING TO SLOWLY COOL NEAR THE IMMEDIATE LAKE SHORE OF
NORTHEAST ILLINOIS...INCLUDING DOWNTOWN CHICAGO...WHERE RAIN OR
RAIN/SNOW MIX WITH LITTLE TO NO ACCUMULATION HAS BEEN REPORTED
THUS FAR THIS MORNING. EXPECTING TO SEE THESE LOCATIONS TURN OVER
TO ALL SNOW FOR GOOD OVER THE NEXT COUPLE HOURS.
AS DEFORMATION ENVELOPS THE AREA AS NOTED IN THE PREVIOUS
DISCUSSION...WE SHOULD CONTINUE TO SEE HEAVIER SNOW BLOSSOM ON
RADAR WHICH WE HAVE NOTICED UNDULATE SINCE 7 AM. AREAS OF HALF
MILE AND TEMPORARY QUARTER MILE VISIBILITY HAVE BEEN OBSERVED
UNDER THESE. SNOWFLAKE QUALITY...OR SNOW RATIOS...ALSO APPEAR TO
INCREASE IN THESE AREAS BASED ON OUT OUR WINDOW AND A FEW OTHER
REPORTS. THAT WOULD LINE UP WITH SATURATION PROFILES...ESPECIALLY
WHERE THE WINDS ARE LIGHTER IN THE LOW-LEVELS /LESS FLAKE
FRAGMENTING/...SUCH AS NORTHEAST ILLINOIS AND FAR NORTHWEST
INDIANA AT PRESENT. TEMPORARY ONE INCH PER HOUR RATES WILL BE
MOST FAVORED IN THESE AREAS.
LAKE ENHANCEMENT CONTINUES TO BE SEEN NEAR THE WI/IL STATE
LINE...WITH EVEN SOME 40 MPH GUSTS ON THE IMMEDIATE SOUTHEAST
WISCONSIN SHORE LIKELY INDICATING THE PRESENCE OF SHARPENING
CONVERGENCE AND STEEP LAPSE RATES. THIS ENHANCEMENT WILL SLOWLY
MOVE SOUTHWARD THROUGH EARLY AFTERNOON...WITH THE LONGEST
RESIDENCE TIME JUST NORTH OF CHICAGO IT WOULD APPEAR ON THE HRRR
AND RAP PREDICTED WIND FIELDS. THIS WILL SHIFT INTO NORTHWEST
INDIANA DURING THE MID AFTERNOON OR SO AND FURTHER INCREASE RATES
AND TOTAL SNOW. WHILE SNOWFALL TOTALS IN PARTS OF LAKE AND PORTER
ARE LIKELY TO NOT REACH SIX INCHES...THE COMBINATION OF THE
HEAVIER SYNOPTIC AND EXPECTED LATER MESOSCALE RATES DURING THE
DAYTIME...AND THE FIRST EVENT OF THE YEAR...HAVE COLLABORATED THE
UPGRADE TO WARNING FOR THERE.
MTF
&&
.SHORT TERM...
330 AM CST
THROUGH MONDAY...
A VERY IMPRESSIVE DYNAMIC EARLY SEASON STORM SYSTEM HAS ONLY
PRESENTED ITS FIRST PUNCH TO PORTIONS OF THE AREA. YESTERDAY
EVENING...A VERY STRONGLY FRONTOGENTICALLY FORCED HEAVY SNOW BAND
DEVELOPED OVER FAR NORTHERN ILLINOIS AND DROPPED UP TO 10 INCHES
WITHIN A FEW HOURS. HOWEVER...AREAS FARTHER SOUTH RECEIVED LIGHTER
AMOUNTS OUT OF THIS FIRST PERIOD OF SNOW. THIS IS EXPECTED TO
CHANGE THIS MORNING...HOWEVER...AS ADDITIONAL MODERATE TO
OCCASIONALLY HEAVY BANDS OF SNOW DEVELOP OVER THE AREA AND PRESENT
THE OPPORTUNITY FOR AREAS SOUTH OF YESTERDAY EVENINGS HEAVY SNOW
EVENT TO GET SNOW ACCUMULATION.
THE TRACKS OF THE 850 AND 700 MB LOWS APPEAR QUITE FAVORABLE FOR
HEAVY SNOW ACROSS NORTHERN ILLINOIS AND NORTHWESTERN INDIANA TODAY.
STRONG Q-VECTOR CONVERGENCE IS EXPECTED TO SET UP OVER THE REGION
THIS MORNING AS THE MAIN MID LEVEL SHORT WAVE TRANSITIONS TO A
NEGATIVE TILT. THIS SUGGESTS THE PRESENCE OF STRONG LARGE SCALE
FORCING FOR ASCENT...ESPECIALLY CONSIDERING THE AREA WILL RESIDE
WITHIN THE FAVORABLE LEFT EXIT REGION OF A 120+ KT UPPER LEVEL JET.
AS THE LOWER LEVEL LOW SHIFTS EASTWARD OVER ILLINOIS...THIS WILL
RESULT IN A CORRIDOR OF RATHER STOUT DEFORMATION...AND THE RESULTANT
BANDS OF FRONTOGENESIS SHOULD DIVE AN AREA OF MODERATE...TO
OCCASIONALLY HEAVY SNOW OVER THE AREA TODAY. THIS STRONG FORCING FOR
ASCENT ALSO LOOKS TO BE COMPLEMENTED...AT LEAST OVER NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA...BY FAVORABLE THERMODYNAMICS FOR
LAKE ENHANCEMENT.
SURFACE TEMPERATURES HAVE REMAINED AT...OR A COUPLE OF DEGREES ABOVE
FREEZING THROUGH THE NIGHT IN MOST AREAS OUTSIDE OF NORTH CENTRAL
ILLINOIS...AND THIS HAS RESULTED IN LITTLE SNOW
ACCUMULATION...ESPECIALLY CONSIDERING SNOW RATES HAVE REMAINED
FAIRLY LIGHT OVERNIGHT. SURFACE TEMPERATURES SHOULD BEGIN TO COOL TO
AND BELOW FREEZING DURING THE DAY AS HEAVIER PRECIPITATION RATES
DEVELOP...AND THIS SHOULD ALLOW SNOW TO ACCUMULATE...ESPECIALLY ON
GRASSY AREAS. IT IS A BIT UNCERTAIN HOW MUCH SNOW WILL ACCUMULATE ON
PAVEMENT...DUE TO THE WARMER TEMPERATURES. HOWEVER...AT LEAST SOME
SLUSHY ACCUMS LOOKS POSSIBLE.
AS MENTIONED ABOVE...THERMODYNAMICS SHOULD BECOME INCREASING
FAVORABLE FOR A LAKE ENHANCED BAND OF SNOW TO DEVELOP OVER
NORTHEASTERN ILLINOIS AND EVENTUALLY NORTHWESTERN INDIANA. COOLER
MID-LEVEL TEMPERATURES MOVING OVER THE AREA SHOULD SET UP THESE
FAVORABLE CONDITIONS. HI-RES GUIDANCE IS ACTUALLY PICKING UP ON
THIS...AND SUGGESTS THAT A HEAVY LAKE ENHANCED BAND OF HEAVY SNOW
WILL IMPACT PORTIONS OF NORTHEASTERN ILLINOIS THIS MORNING.
IT APPEARS THAT THE STORM SYSTEM WILL TRACK A BIT FARTHER SOUTH THEN
WHAT WAS ANTICIPATED EARLIER. THEREFORE...IT APPEARS THAT AREAS
OUTSIDE THE CURRENT ADVISORY COULD END UP GETTING A FEW INCHES OF
ACCUMULATION TODAY. BECAUSE OF THIS...WE OPTED TO EXPAND THE WINTER
WX ADVISORY FARTHER SOUTH TO COVER THE REST OF MY AREA. OVERALL...IT
APPEARS THE HEAVIEST SNOW TODAY WILL FALL DURING THE MORNING...THEN
BEGIN TAPERING OFF FROM WEST TO EAST THROUGH THE AFTERNOON. LAKE
ENHANCED SNOW SHOWERS COULD LINGER INTO THE EVENING OVER FAR
NORTHEASTERN PORTER. OTHERWISE...THINGS SHOULD BE DONE IN MOST
AREAS BY LATER THIS AFTERNOON. IT APPEARS THAT AMOUNTS OF 3 TO 7
INCHES COULD FALL ACROSS THE AREA TODAY. THEREFORE...NO CHANGES
ARE PLANED TO THE HEADLINES...ASIDE FROM THE EXPANSION MENTIONED.
NORTH-NORTHWESTERLY WINDS WILL BECOME VERY GUSTY THIS AFTERNOON AS
THE SURFACE LOW TRACKS OVER THE EASTERN GREAT LAKES REGION. THESE
STRONGER WINDS COULD PRODUCE SOME BLOWING SNOW. HOWEVER...DUE TO THE
WETTER NATURE OF THE SNOW...THIS MAY NOT BE TOO BIG OF AN
ISSUE...AND I HAVE OPTED TO LEAVE THE MENTION OUT OF THE FORECAST AT
THIS TIME.
OTHERWISE...EXPECT A VERY COLD NIGHT TONIGHT WITH THE FRESH SNOW ON
THE GROUND. AREAS ACROSS NORTH CENTRAL ILLINOIS LOOK TO DROP INTO
THE SINGLE DIGITS...WITH TEENS LIKELY IN MOST OTHER AREAS.
SUBFREEZING TEMPERATURES WILL CONTINUE SUNDAY...BEFORE TEMPERATURES
BEGIN TO INCH ABOVE FREEZING ON MONDAY.
KJB
&&
.LONG TERM...
238 AM CST
TUESDAY THROUGH FRIDAY...
THE EXTENDED BEGINS QUIETLY WITH HIGH PRESSURE SHIFTING FROM THE
SOUTHEAST U.S. TO NEW ENGLAND BY WEDNESDAY MORNING. WINDS TURN
SOUTH WEDNESDAY USHERING IN WARMER AIR. THIS IS REFLECTED IN HIGH
TEMPS WHICH WILL JUMP FROM THE UPPER 30S TO MID 40S TUESDAY TO THE
LOW TO MID 50S THURSDAY. A WEAKENING MID LEVEL SHORTWAVE TROUGH
PASSES OVER THE REGION WEDNESDAY BRINGING A SLIGHT CHANCE TO CHANCE
OF LIGHT RAIN WITH IT. HAVE MORE CONFIDENCE IN RAIN WEDNESDAY NIGHT
THAN WEDNESDAY AS THE NEXT LOW/S WARM FRONT LIFTS NORTH OVER THE
REGION...BUT ONLY EXPECTING LIGHT RAIN. THE LOW ARRIVES OVER IOWA
THURSDAY MORNING AND CONTINUES NORTHEAST THROUGH LATE IN THE WEEK.
THE GFS IS MORE AGGRESSIVE WITH THE RAIN/S PROGRESSION THURSDAY.
THINKING AREAS WEST OF I-55 WILL LIKELY SEE RAIN WHILE THE GFS
SUGGESTS THE WHOLE WARNING AREA WILL RECEIVE RAIN. GUSTY SOUTH
WINDS ARE ALSO EXPECTED THURSDAY WITH GUSTS UP TO 30 MPH. THE LOW/S
COLD FRONT SWINGS THROUGH FRIDAY LEADING TO COOLER TEMPS...AN END TO
THE RAIN...AND NORTHWEST TO WEST WINDS. HIGH TEMPS FRIDAY WILL STILL
BE AROUND TO SLIGHTLY ABOVE AVERAGE RANGING FROM THE MID 40S TO
AROUND 50.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* ONGOING SNOW THROUGH THE EARLY AFTERNOON. VSBYS WILL DROP AGAIN
TO NEAR 1/2SM WITH A LAKE EFFECT BAND FROM 17-202Z.
* IFR TO LIFR CIGS IMPROVING IN THE AFTERNOON.
* NORTHEAST WINDS ARE SHIFTING NORTHERLY CURRENTLY. ANOTHER SHIFT TO
NNW AND GUST TO 20-25KT EXPECTED THIS AFTN.
MM
//DISCUSSION...UPDATED 12Z...
SNOW WILL INCREASE THIS MORNING WITH 3/4 SM VSBY EXPECTED AT ALL
OF THE TAF SITES. PERIODS OF 1/4 SM VSBY ARE NOT OUT OF THE
QUESTION ACROSS THE EASTERN TERMINALS. A LAKE EFFECT BAND WILL
FORM LATE THIS MORNING AND ROTATE OVER THE EASTERN TERMINALS.
1/4SM WITH HEAVY SNOW IS EXPECTED UNDER THIS BAND ALONG WITH QUICK
ACCUMULATIONS. HOWEVER THE BAND WILL BE TRANSIENT SO THE HEAVY
SNOW WILL LAST ABOUT AN HOUR OR LESS. RFD WILL NOT BE AFFECTED BY
THE BAND AND WILL SEE THE SNOW END FIRST AROUND NOON. EAST WINDS
WILL BE LESS THAN 10 KT EARLY THIS MORNING AND INCREASE TO CLOSE
TO 10 KT LATE THIS MORNING. WINDS WILL BE BACKING LATE THIS
MORNING AND BECOME NORTHWEST GUSTING TO 20-25 KT EARLY THIS AFTN.
FLURRIES OR LIGHT SNOW MAY PERSIST PAST 19Z AT THE EASTERN
TERMINALS...BUT NOT EXPECTING ANY SIGNIFICANT IMPACT FROM THE
LINGERING SNOW.
LIFR CIGS WILL LIFT AFTER THE SNOW TO MVFR AND CLEAR OUT THIS
EVENING WITH WINDS BECOMING SOUTHWEST SUNDAY MORNING.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH ON SNOW VSBYS THE NEXT 2 HOURS...MEDIUM HIGH CONFIDENCE IN
A LAKE EFFECT BAND DEVELOPING...BUT MEDIUM ON TIMING AND LOWESTY
VSBYS.
* HIGH ON CIG TRENDS.
* MEDIUM ON WIND TRENDS.
MM
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR. SOUTHWEST WINDS.
MONDAY...VFR. WEST WINDS.
TUESDAY...VFR. SOUTH WINDS.
WEDNESDAY...SCHC-CHC -RA. SOUTH WINDS.
THURSDAY...RA LIKELY. MVFR PSBL. GUSTY SOUTH WINDS BECOMING WEST.
FRIDAY...CHC RAIN. IMPROVING TO VFR. NORTHWEST WINDS.
JEE
&&
.MARINE...
238 AM CST
NO CHANGES TO CURRENT SMALL CRAFT ADVISORY AND GALE WARNING. WILL
LIKELY NEED ANOTHER GALE HEADLINE FOR THE SOUTHERN HALF OF THE LAKE
SUNDAY EVENING AND NIGHT...BUT WILL HOLD OFF ON ISSUING ONE NOW
GIVEN THE CURRENT HEADLINES.
WINDS WILL BECOME NORTH TO NORTHWEST ACROSS THE LAKE THIS AFTERNOON
AS THE LOW PRESSURE SYSTEM CURRENTLY OVER TEXAS MOVES OVER THE OHIO
RIVER VALLEY. NW WINDS WILL INCREASE TO GALE FORCE ACROSS THE
SOUTHERN HALF OF THE LAKE AND INDIANA NEARSHORE ZONES. WINDS
DIMINISH OVERNIGHT AS THE LOW MOVES OVER QUEBEC. HIGH PRESSURE
SPREADS OVER THE SOUTHERN MISSISSIPPI VALLEY AND SOUTHEAST U.S. AS
ANOTHER LOW SHIFTS SOUTHEAST OVER ONTARIO SUNDAY NIGHT INTO MONDAY.
WINDS BACK TO SOUTHWEST AND GALES ARE EXPECTED SUNDAY NIGHT ACROSS
THE SOUTHERN HALF OF THE LAKE. WINDS DIMINISH AND BECOME WEST BEHIND
THE LOWS COLD FRONT MONDAY. WINDS BACK TO SOUTH AHEAD OF THE NEXT
LOW TUESDAY AND INCREASE TO 15-25 KT WEDNESDAY. THE LOW IS PROGGED
TO PASS JUST NORTHWEST AND NORTH OF THE LAKE THURSDAY NIGHT INTO
FRIDAY WITH SOUTH WINDS INCREASING TO AT LEAST 30 KT THURSDAY
BECOMING WEST 20-25 KT BEHIND THE LOW. SOME GUIDANCE MEMBERS DO
SUGGEST WE COULD HAVE GALES THURSDAY.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ022 UNTIL 3 PM
SATURDAY.
WINTER WEATHER ADVISORY...ILZ021-ILZ023-ILZ032-ILZ033-ILZ039
UNTIL 3 PM SATURDAY.
IN...WINTER STORM WARNING...INZ001-INZ002 UNTIL 6 PM SATURDAY.
WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 6 PM
SATURDAY.
LM...GALE WARNING...ILLINOIS NEARSHORE WATERS UNTIL 9 PM SATURDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...9 PM SATURDAY TO 9
AM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745-LMZ777-LMZ779...3 PM
SATURDAY TO 3 AM SUNDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 3 PM SATURDAY.
&&
$$
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
917 AM CST SAT NOV 21 2015
.UPDATE...
915 AM CST
ONLY CHANGE TO HEADLINES WAS TO UPGRADE ADVISORY TO A WINTER STORM
WARNING FOR LAKE AND PORTER COUNTIES IN NORTHWEST INDIANA.
MAJORITY OF FORECAST CONTINUES WELL ON TRACK...INCLUDING FOR THE
MOST PART SNOWFALL TOTALS AND ENDING TIMES TODAY.
THE WELL-DEFINED TROUGH ON SATELLITE THIS MORNING IS SWINGING
INTO THE AREA...PIVOTING SLIGHTLY MORE NEGATIVELY TILTED...WITH
RAPID MID-LEVEL AND DYNAMIC COOLING. AN IMPRESSIVE 500MB
TEMPERATURE DIFFERENCE FROM MPX TO DVN OF 16C HIGHLIGHTS THAT.
THE SURFACE TEMPERATURES ARE STARTING TO SLOWLY FALL IN NORTH
CENTRAL ILLINOIS WITH NORTHERLY WINDS. TEMPERATURES ARE ALSO
BEGINNING TO SLOWLY COOL NEAR THE IMMEDIATE LAKE SHORE OF
NORTHEAST ILLINOIS...INCLUDING DOWNTOWN CHICAGO...WHERE RAIN OR
RAIN/SNOW MIX WITH LITTLE TO NO ACCUMULATION HAS BEEN REPORTED
THUS FAR THIS MORNING. EXPECTING TO SEE THESE LOCATIONS TURN OVER
TO ALL SNOW FOR GOOD OVER THE NEXT COUPLE HOURS.
AS DEFORMATION ENVELOPS THE AREA AS NOTED IN THE PREVIOUS
DISCUSSION...WE SHOULD CONTINUE TO SEE HEAVIER SNOW BLOSSOM ON
RADAR WHICH WE HAVE NOTICED UNDULATE SINCE 7 AM. AREAS OF HALF
MILE AND TEMPORARY QUARTER MILE VISIBILITY HAVE BEEN OBSERVED
UNDER THESE. SNOWFLAKE QUALITY...OR SNOW RATIOS...ALSO APPEAR TO
INCREASE IN THESE AREAS BASED ON OUT OUR WINDOW AND A FEW OTHER
REPORTS. THAT WOULD LINE UP WITH SATURATION PROFILES...ESPECIALLY
WHERE THE WINDS ARE LIGHTER IN THE LOW-LEVELS /LESS FLAKE
FRAGMENTING/...SUCH AS NORTHEAST ILLINOIS AND FAR NORTHWEST
INDIANA AT PRESENT. TEMPORARY ONE INCH PER HOUR RATES WILL BE
MOST FAVORED IN THESE AREAS.
LAKE ENHANCEMENT CONTINUES TO BE SEEN NEAR THE WI/IL STATE
LINE...WITH EVEN SOME 40 MPH GUSTS ON THE IMMEDIATE SOUTHEAST
WISCONSIN SHORE LIKELY INDICATING THE PRESENCE OF SHARPENING
CONVERGENCE AND STEEP LAPSE RATES. THIS ENHANCEMENT WILL SLOWLY
MOVE SOUTHWARD THROUGH EARLY AFTERNOON...WITH THE LONGEST
RESIDENCE TIME JUST NORTH OF CHICAGO IT WOULD APPEAR ON THE HRRR
AND RAP PREDICTED WIND FIELDS. THIS WILL SHIFT INTO NORTHWEST
INDIANA DURING THE MID AFTERNOON OR SO AND FURTHER INCREASE RATES
AND TOTAL SNOW. WHILE SNOWFALL TOTALS IN PARTS OF LAKE AND PORTER
ARE LIKELY TO NOT REACH SIX INCHES...THE COMBINATION OF THE
HEAVIER SYNOPTIC AND EXPECTED LATER MESOSCALE RATES DURING THE
DAYTIME...AND THE FIRST EVENT OF THE YEAR...HAVE COLLABORATED THE
UPGRADE TO WARNING FOR THERE.
MTF
&&
.SHORT TERM...
330 AM CST
THROUGH MONDAY...
A VERY IMPRESSIVE DYNAMIC EARLY SEASON STORM SYSTEM HAS ONLY
PRESENTED ITS FIRST PUNCH TO PORTIONS OF THE AREA. YESTERDAY
EVENING...A VERY STRONGLY FRONTOGENTICALLY FORCED HEAVY SNOW BAND
DEVELOPED OVER FAR NORTHERN ILLINOIS AND DROPPED UP TO 10 INCHES
WITHIN A FEW HOURS. HOWEVER...AREAS FARTHER SOUTH RECEIVED LIGHTER
AMOUNTS OUT OF THIS FIRST PERIOD OF SNOW. THIS IS EXPECTED TO
CHANGE THIS MORNING...HOWEVER...AS ADDITIONAL MODERATE TO
OCCASIONALLY HEAVY BANDS OF SNOW DEVELOP OVER THE AREA AND PRESENT
THE OPPORTUNITY FOR AREAS SOUTH OF YESTERDAY EVENINGS HEAVY SNOW
EVENT TO GET SNOW ACCUMULATION.
THE TRACKS OF THE 850 AND 700 MB LOWS APPEAR QUITE FAVORABLE FOR
HEAVY SNOW ACROSS NORTHERN ILLINOIS AND NORTHWESTERN INDIANA TODAY.
STRONG Q-VECTOR CONVERGENCE IS EXPECTED TO SET UP OVER THE REGION
THIS MORNING AS THE MAIN MID LEVEL SHORT WAVE TRANSITIONS TO A
NEGATIVE TILT. THIS SUGGESTS THE PRESENCE OF STRONG LARGE SCALE
FORCING FOR ASCENT...ESPECIALLY CONSIDERING THE AREA WILL RESIDE
WITHIN THE FAVORABLE LEFT EXIT REGION OF A 120+ KT UPPER LEVEL JET.
AS THE LOWER LEVEL LOW SHIFTS EASTWARD OVER ILLINOIS...THIS WILL
RESULT IN A CORRIDOR OF RATHER STOUT DEFORMATION...AND THE RESULTANT
BANDS OF FRONTOGENESIS SHOULD DIVE AN AREA OF MODERATE...TO
OCCASIONALLY HEAVY SNOW OVER THE AREA TODAY. THIS STRONG FORCING FOR
ASCENT ALSO LOOKS TO BE COMPLEMENTED...AT LEAST OVER NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA...BY FAVORABLE THERMODYNAMICS FOR
LAKE ENHANCEMENT.
SURFACE TEMPERATURES HAVE REMAINED AT...OR A COUPLE OF DEGREES ABOVE
FREEZING THROUGH THE NIGHT IN MOST AREAS OUTSIDE OF NORTH CENTRAL
ILLINOIS...AND THIS HAS RESULTED IN LITTLE SNOW
ACCUMULATION...ESPECIALLY CONSIDERING SNOW RATES HAVE REMAINED
FAIRLY LIGHT OVERNIGHT. SURFACE TEMPERATURES SHOULD BEGIN TO COOL TO
AND BELOW FREEZING DURING THE DAY AS HEAVIER PRECIPITATION RATES
DEVELOP...AND THIS SHOULD ALLOW SNOW TO ACCUMULATE...ESPECIALLY ON
GRASSY AREAS. IT IS A BIT UNCERTAIN HOW MUCH SNOW WILL ACCUMULATE ON
PAVEMENT...DUE TO THE WARMER TEMPERATURES. HOWEVER...AT LEAST SOME
SLUSHY ACCUMS LOOKS POSSIBLE.
AS MENTIONED ABOVE...THERMODYNAMICS SHOULD BECOME INCREASING
FAVORABLE FOR A LAKE ENHANCED BAND OF SNOW TO DEVELOP OVER
NORTHEASTERN ILLINOIS AND EVENTUALLY NORTHWESTERN INDIANA. COOLER
MID-LEVEL TEMPERATURES MOVING OVER THE AREA SHOULD SET UP THESE
FAVORABLE CONDITIONS. HI-RES GUIDANCE IS ACTUALLY PICKING UP ON
THIS...AND SUGGESTS THAT A HEAVY LAKE ENHANCED BAND OF HEAVY SNOW
WILL IMPACT PORTIONS OF NORTHEASTERN ILLINOIS THIS MORNING.
IT APPEARS THAT THE STORM SYSTEM WILL TRACK A BIT FARTHER SOUTH THEN
WHAT WAS ANTICIPATED EARLIER. THEREFORE...IT APPEARS THAT AREAS
OUTSIDE THE CURRENT ADVISORY COULD END UP GETTING A FEW INCHES OF
ACCUMULATION TODAY. BECAUSE OF THIS...WE OPTED TO EXPAND THE WINTER
WX ADVISORY FARTHER SOUTH TO COVER THE REST OF MY AREA. OVERALL...IT
APPEARS THE HEAVIEST SNOW TODAY WILL FALL DURING THE MORNING...THEN
BEGIN TAPERING OFF FROM WEST TO EAST THROUGH THE AFTERNOON. LAKE
ENHANCED SNOW SHOWERS COULD LINGER INTO THE EVENING OVER FAR
NORTHEASTERN PORTER. OTHERWISE...THINGS SHOULD BE DONE IN MOST
AREAS BY LATER THIS AFTERNOON. IT APPEARS THAT AMOUNTS OF 3 TO 7
INCHES COULD FALL ACROSS THE AREA TODAY. THEREFORE...NO CHANGES
ARE PLANED TO THE HEADLINES...ASIDE FROM THE EXPANSION MENTIONED.
NORTH-NORTHWESTERLY WINDS WILL BECOME VERY GUSTY THIS AFTERNOON AS
THE SURFACE LOW TRACKS OVER THE EASTERN GREAT LAKES REGION. THESE
STRONGER WINDS COULD PRODUCE SOME BLOWING SNOW. HOWEVER...DUE TO THE
WETTER NATURE OF THE SNOW...THIS MAY NOT BE TOO BIG OF AN
ISSUE...AND I HAVE OPTED TO LEAVE THE MENTION OUT OF THE FORECAST AT
THIS TIME.
OTHERWISE...EXPECT A VERY COLD NIGHT TONIGHT WITH THE FRESH SNOW ON
THE GROUND. AREAS ACROSS NORTH CENTRAL ILLINOIS LOOK TO DROP INTO
THE SINGLE DIGITS...WITH TEENS LIKELY IN MOST OTHER AREAS.
SUBFREEZING TEMPERATURES WILL CONTINUE SUNDAY...BEFORE TEMPERATURES
BEGIN TO INCH ABOVE FREEZING ON MONDAY.
KJB
&&
.LONG TERM...
238 AM CST
TUESDAY THROUGH FRIDAY...
THE EXTENDED BEGINS QUIETLY WITH HIGH PRESSURE SHIFTING FROM THE
SOUTHEAST U.S. TO NEW ENGLAND BY WEDNESDAY MORNING. WINDS TURN
SOUTH WEDNESDAY USHERING IN WARMER AIR. THIS IS REFLECTED IN HIGH
TEMPS WHICH WILL JUMP FROM THE UPPER 30S TO MID 40S TUESDAY TO THE
LOW TO MID 50S THURSDAY. A WEAKENING MID LEVEL SHORTWAVE TROUGH
PASSES OVER THE REGION WEDNESDAY BRINGING A SLIGHT CHANCE TO CHANCE
OF LIGHT RAIN WITH IT. HAVE MORE CONFIDENCE IN RAIN WEDNESDAY NIGHT
THAN WEDNESDAY AS THE NEXT LOW/S WARM FRONT LIFTS NORTH OVER THE
REGION...BUT ONLY EXPECTING LIGHT RAIN. THE LOW ARRIVES OVER IOWA
THURSDAY MORNING AND CONTINUES NORTHEAST THROUGH LATE IN THE WEEK.
THE GFS IS MORE AGGRESSIVE WITH THE RAIN/S PROGRESSION THURSDAY.
THINKING AREAS WEST OF I-55 WILL LIKELY SEE RAIN WHILE THE GFS
SUGGESTS THE WHOLE WARNING AREA WILL RECEIVE RAIN. GUSTY SOUTH
WINDS ARE ALSO EXPECTED THURSDAY WITH GUSTS UP TO 30 MPH. THE LOW/S
COLD FRONT SWINGS THROUGH FRIDAY LEADING TO COOLER TEMPS...AN END TO
THE RAIN...AND NORTHWEST TO WEST WINDS. HIGH TEMPS FRIDAY WILL STILL
BE AROUND TO SLIGHTLY ABOVE AVERAGE RANGING FROM THE MID 40S TO
AROUND 50.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* PERIODS OF SNOW THROUGH THE EARLY AFTERNOON WITH VSBYS DROPPING AS
LOW AS 1/4SM DURING HEAVIEST PERIODS OF SNOW.
* IFR TO LIFR CIGS THROUGH THIS MORNING...IMPROVING TO VFR THIS
EVENING.
* EAST WINDS LESS THAN 10 KT BECOME NE AND INCREASE TO ARND 10 KT
LATE THIS MORNING. WINDS THEN BACK TO NNW AND GUST TO 20-25KT
THIS AFTN.
JEE/MM
//DISCUSSION...UPDATED 12Z...
SNOW WILL INCREASE THIS MORNING WITH 3/4 SM VSBY EXPECTED AT ALL
OF THE TAF SITES. PERIODS OF 1/4 SM VSBY ARE NOT OUT OF THE
QUESTION ACROSS THE EASTERN TERMINALS. A LAKE EFFECT BAND WILL
FORM LATE THIS MORNING AND ROTATE OVER THE EASTERN TERMINALS.
1/4SM WITH HEAVY SNOW IS EXPECTED UNDER THIS BAND ALONG WITH QUICK
ACCUMULATIONS. HOWEVER THE BAND WILL BE TRANSIENT SO THE HEAVY
SNOW WILL LAST ABOUT AN HOUR OR LESS. RFD WILL NOT BE AFFECTED BY
THE BAND AND WILL SEE THE SNOW END FIRST AROUND NOON. EAST WINDS
WILL BE LESS THAN 10 KT EARLY THIS MORNING AND INCREASE TO CLOSE
TO 10 KT LATE THIS MORNING. WINDS WILL BE BACKING LATE THIS
MORNING AND BECOME NORTHWEST GUSTING TO 20-25 KT EARLY THIS AFTN.
FLURRIES OR LIGHT SNOW MAY PERSIST PAST 19Z AT THE EASTERN
TERMINALS...BUT NOT EXPECTING ANY SIGNIFICANT IMPACT FROM THE
LINGERING SNOW.
LIFR CIGS WILL LIFT AFTER THE SNOW TO MVFR AND CLEAR OUT THIS
EVENING WITH WINDS BECOMING SOUTHWEST SUNDAY MORNING.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE IN SNOW THROUGH THE MORNING WITH PERIODS OF LIFR
VSBY UNDER HEAVIEST SNOW BANDS.
* MEDIUM-HIGH CONFIDENCE IN OCCURRENCE AND TIMING OF A LAKE EFFECT
BAND WITH 1/4SM VSBY.
* HIGH CONFIDENCE IN CIG AND WIND TRENDS.
JEE/MM
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR. SOUTHWEST WINDS.
MONDAY...VFR. WEST WINDS.
TUESDAY...VFR. SOUTH WINDS.
WEDNESDAY...SCHC-CHC -RA. SOUTH WINDS.
THURSDAY...RA LIKELY. MVFR PSBL. GUSTY SOUTH WINDS BECOMING WEST.
FRIDAY...CHC RAIN. IMPROVING TO VFR. NORTHWEST WINDS.
JEE
&&
.MARINE...
238 AM CST
NO CHANGES TO CURRENT SMALL CRAFT ADVISORY AND GALE WARNING. WILL
LIKELY NEED ANOTHER GALE HEADLINE FOR THE SOUTHERN HALF OF THE LAKE
SUNDAY EVENING AND NIGHT...BUT WILL HOLD OFF ON ISSUING ONE NOW
GIVEN THE CURRENT HEADLINES.
WINDS WILL BECOME NORTH TO NORTHWEST ACROSS THE LAKE THIS AFTERNOON
AS THE LOW PRESSURE SYSTEM CURRENTLY OVER TEXAS MOVES OVER THE OHIO
RIVER VALLEY. NW WINDS WILL INCREASE TO GALE FORCE ACROSS THE
SOUTHERN HALF OF THE LAKE AND INDIANA NEARSHORE ZONES. WINDS
DIMINISH OVERNIGHT AS THE LOW MOVES OVER QUEBEC. HIGH PRESSURE
SPREADS OVER THE SOUTHERN MISSISSIPPI VALLEY AND SOUTHEAST U.S. AS
ANOTHER LOW SHIFTS SOUTHEAST OVER ONTARIO SUNDAY NIGHT INTO MONDAY.
WINDS BACK TO SOUTHWEST AND GALES ARE EXPECTED SUNDAY NIGHT ACROSS
THE SOUTHERN HALF OF THE LAKE. WINDS DIMINISH AND BECOME WEST BEHIND
THE LOWS COLD FRONT MONDAY. WINDS BACK TO SOUTH AHEAD OF THE NEXT
LOW TUESDAY AND INCREASE TO 15-25 KT WEDNESDAY. THE LOW IS PROGGED
TO PASS JUST NORTHWEST AND NORTH OF THE LAKE THURSDAY NIGHT INTO
FRIDAY WITH SOUTH WINDS INCREASING TO AT LEAST 30 KT THURSDAY
BECOMING WEST 20-25 KT BEHIND THE LOW. SOME GUIDANCE MEMBERS DO
SUGGEST WE COULD HAVE GALES THURSDAY.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ022 UNTIL 3 PM
SATURDAY.
WINTER WEATHER ADVISORY...ILZ021-ILZ023-ILZ032-ILZ033-ILZ039
UNTIL 3 PM SATURDAY.
IN...WINTER STORM WARNING...INZ001-INZ002 UNTIL 6 PM SATURDAY.
WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 6 PM
SATURDAY.
LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 9 AM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745-LMZ777-LMZ779...3 PM
SATURDAY TO 3 AM SUNDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 3 PM SATURDAY.
&&
$$
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
National Weather Service Lincoln IL
608 AM CST SAT NOV 21 2015
.SHORT TERM...(Today)
ISSUED AT 336 AM CST SAT NOV 21 2015
the 09z/3am surface analysis shows the center of the low pressure in
south-central Missouri, with a warm front extending across southern
IL, roughly along I-70. The rain-snow line has maintained farther
north...with snow remaining north of a line from Macomb to Peoria to
Pontiac. The Peoria airport just SW of Peoria has little to no snow,
while the north side of Peoria has what looks to be at least an inch
of snow, and possibly more, on grassy surfaces based on IDOT
cameras. Reports of 2.5" of snow have come in from Knox county
observers in Altona and Abingdon earlier tonight.
The RAP and HRRR take the surface low across southern IL, with
deformation band snows continuing in our NW counties. Cold air along
the northern edge of the system will gradually get pulled southward
into our counties, prompting the rain to change to snow
progressively farther south and east. Snowfall amounts look on track
for our NW counties to be in the 3 to 6 inch range, with a sharp
cutoff down to an inch or less. As the deformation band progresses
across central IL into the afternoon, our NE counties could see
snowfall amounts up to an inch or possibly a little more toward
Hoopeston. We did not expand the winter weather advisory eastward, as
snow amounts should remain enough below the 3" criteria for
Champaign and Vermilion counties. The southern row of counties of
our advisory (Fulton, Tazewell, McLean) will be borderline in terms
of snow amounts as well, but will continue with headlines unchanged
as there remains some uncertainty as to how soon the cold air will
surge southward to change rain to snow, and how efficient of
snowfall production will occur in our NW areas.
Temps will remain warm enough for rain south of I-72 for a majority
of the day, with any change to snow coming so late in the event
that little to no snow accumulation is expected south of there.
The center of the surface low is forecast to pull into Indiana by 11
am/17z, so cold air will invade on strong NW winds by early
afternoon. High temps will likely occur by Noon in most areas
because of that, with steady or falling temps this afternoon as
winds increase to 25-30 mph. The snow should generally be too wet to
blow around, but wind chills could drop into the teens in our W-NW
counties.
.LONG TERM...(Tonight through Friday)
ISSUED AT 336 AM CST SAT NOV 21 2015
Strong short wave to lift ne of central IL early this evening with
Canadian high pressure over the central Rockies quickly ridging east
into the mid MS river valley by dawn Sunday. Clouds to decrease from
west to east later this afternoon and into the evening while nw
winds 15-25 mph at sunset today diminish to 5-10 mph overnight.
Diminishing clouds and winds to bring a very cold night to the
area especially over northern CWA where snow cover where lows will
be 7- 13F with mid teens over central parts of CWA and upper teens
to near 20F in southeast IL. Wind chills will lower to 5 above to
5 below zero northern cwa and 10-15 southeast IL. This will be the
coldest night since March 6th over central IL. High pressure
ridges into the Ohio river valley by sunset Sunday while upper
level trof axis shifts east of IL. A mostly sunny but cold day
with highs ranging form lower 30s from i-74 ne, mid 30s central
CWA and upper 30s sw CWA. Winds to become ssw at 7-14 mph by
Sunday afternoon.
After a taste of winter weather this weekend for IL, temperatures to
moderate back above normal during the upcoming work week with upper
level heights rising over the region and nearly zonal upper level
flow Monday becoming sw by mid week with strong upper level ridge in
the east and strong upper level low/trof digging in the western
states. Dry weather expected Monday through Wednesday with temps
warming back up. Lows Sunday night in the mid to upper 20s. Highs
Monday range from lower 40s from I-74 ne where remaining snow cover
likely to melt while upper 40s to near 50F sw CWA. Highs by Wed in
the low to mid 50s and mid to upper 50s on Thanksgiving day. 00Z
models have trended slower with qpf returning to IL Wed night and
Thu and looks like a wet period from Wed night into early Sat. GFS
is quicker than ECMWF model with cold front moving through later Thu
night and Friday with highest pops will likely be. Between 1 and 2
inches of rain appear possible during this time frame. Rain chances
diminish next weekend and colder air returns to central/se IL.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
ISSUED AT 600 AM CST SAT NOV 21 2015
Conditions are expected to continue at IFR or LIFR for PIA and BMI
where snow will fall through the morning and into early afternoon.
IFR conditions will develop at SPI, DEC and CMI as the morning
progresses, as rain changes to snow. Low pressure will pass south
of the area this morning, roughly just south of I-70. The low will
move into Indiana before Noon/18z, causing winds to shift to the
NE, then N, then NW by afternoon for all TAF sites. Wind speeds
will increase to 15 to 20kt after 15z, with gusts to 30kt at times
this afternoon. Winds will diminish to 8-12kt after 00z.
Initially, surface temps will hover right around or just above
freezing early this morning for a few hours. Ground temperatures
are generally above freezing, so snow accumulation on travel
surfaces will remain lower than grassy areas. 1 inch of slushy
accumulation could occur at PIA, with less than an inch at BMI and
CMI, and little to no snow accumulation at DEC and SPI. IFR
conditions should gradually improve to MVFR during the afternoon
and then to VFR after 00-03z.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until noon CST today for ILZ027>031-
036>038.
&&
$$
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Shimon
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
336 AM CST SAT NOV 21 2015
.SHORT TERM...(Today)
ISSUED AT 336 AM CST SAT NOV 21 2015
the 09z/3am surface analysis shows the center of the low pressure in
south-central Missouri, with a warm front extending across southern
IL, roughly along I-70. The rain-snow line has maintained farther
north...with snow remaining north of a line from Macomb to Peoria to
Pontiac. The Peoria airport just SW of Peoria has little to no snow,
while the north side of Peoria has what looks to be at least an inch
of snow, and possibly more, on grassy surfaces based on IDOT
cameras. Reports of 2.5" of snow have come in from Knox county
observers in Altona and Abingdon earlier tonight.
The RAP and HRRR take the surface low across southern IL, with
deformation band snows continuing in our NW counties. Cold air along
the northern edge of the system will gradually get pulled southward
into our counties, prompting the rain to change to snow
progressively farther south and east. Snowfall amounts look on track
for our NW counties to be in the 3 to 6 inch range, with a sharp
cutoff down to an inch or less. As the deformation band progresses
across central IL into the afternoon, our NE counties could see
snowfall amounts up to an inch or possibly a little more toward
Hoopeston. We did not expand the winter weather advisory eastward, as
snow amounts should remain enough below the 3" criteria for
Champaign and Vermilion counties. The southern row of counties of
our advisory (Fulton, Tazewell, McLean) will be borderline in terms
of snow amounts as well, but will continue with headlines unchanged
as there remains some uncertainty as to how soon the cold air will
surge southward to change rain to snow, and how efficient of
snowfall production will occur in our NW areas.
Temps will remain warm enough for rain south of I-72 for a majority
of the day, with any change to snow coming so late in the event
that little to no snow accumulation is expected south of there.
The center of the surface low is forecast to pull into Indiana by 11
am/17z, so cold air will invade on strong NW winds by early
afternoon. High temps will likely occur by Noon in most areas
because of that, with steady or falling temps this afternoon as
winds increase to 25-30 mph. The snow should generally be too wet to
blow around, but wind chills could drop into the teens in our W-NW
counties.
&&
.LONG TERM...(Tonight through Friday)
ISSUED AT 336 AM CST SAT NOV 21 2015
Strong short wave to lift ne of central IL early this evening with
Canadian high pressure over the central Rockies quickly ridging east
into the mid MS river valley by dawn Sunday. Clouds to decrease from
west to east later this afternoon and into the evening while nw
winds 15-25 mph at sunset today diminish to 5-10 mph overnight.
Diminshing clouds and winds to bring a very cold night to the area
especially over northern CWA where snow cover where lows will be 7-
13F with mid teens over central parts of CWA and upper teens to near
20F in southeast IL. Wind chills will lower to 5 above to 5 below
zero northern cwa and 10-15 southeast IL. This will be the coldest
night since March 6th over central IL. High pressure ridges into the
Ohio river valley by sunset Sunday while upper level trof axis
shifts east of IL. A mostly sunny but cold day with highs ranging
form lower 30s from i-74 ne, mid 30s central CWA and upper 30s sw
CWA. Winds to become ssw at 7-14 mph by Sunday afternoon.
After a taste of winter weather this weekend for IL, temperatures to
moderate back above normal during the upcoming work week with upper
level heights rising over the region and nearly zonal upper level
flow Monday becoming sw by mid week with strong upper level ridge in
the east and strong upper level low/trof digging in the western
states. Dry weather expected Monday through Wednesday with temps
warming back up. Lows Sunday night in the mid to upper 20s. Highs
Monday range from lower 40s from I-74 ne where remaining snow cover
likely to melt while upper 40s to near 50F sw CWA. Highs by Wed in
the low to mid 50s and mid to upper 50s on Thanksgiving day. 00Z
models have trended slower with qpf returning to IL Wed night and
Thu and looks like a wet period from Wed night into early Sat. GFS
is quicker than ECMWF model with cold front moving through later Thu
night and Friday with highest pops will likely be. Between 1 and 2
inches of rain appear possible during this time frame. Rain chances
diminish next weekend and colder air returns to central/se IL.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 1055 PM CST FRI NOV 20 2015
Conditions are expected to deteriorate to IFR at all sites after
09z as a storm system tracks across the region. Low pressure will
pass south of the area on Saturday insuring a changeover to snow
at the TAF sites with PIA first in the 06-08z time frame...and
then over to BMI by 09z with CMI the last to see the change to
snow. Initially, surface temps will be above freezing but should
edge close to or just below freezing for a few hours Saturday
morning when we should see the steadier snowfall that will
accumulate. IFR conditions should gradualliy improve to MVFR
during the afternoon and then to VFR by 00z. Southeast to east
winds of 10 to 15 kts will back into the northeast and then
north by morning with speeds increasing to 15 to 25 kts during
the morning, and then continue into the afternoon. Gusts around
30 kts will be possible at times as well before we see northwest
winds diminish to around 10 kts around 00z.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until noon CST today for ILZ027>031-
036>038.
&&
$$
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS GOODLAND KS
506 AM MST SAT NOV 21 2015
.UPDATE...
ISSUED AT 456 AM MST SAT NOV 21 2015
SMALL AREA OF FLURRIES MOVING THROUGH THE SOUTHWEST QUADRANT OF
THE AREA AT THIS TIME. HRRR DOES CATCH THIS SMALL AREA. SO ADDED
SCATTERED FLURRIES TO THE ABOVE MENTIONED AREA FOR THE NEXT FEW
HOURS. ALSO INCREASED SKY COVER TO CATCH CURRENT SATELLITE AND
SURFACE OBSERVATION TRENDS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 210 AM MST SAT NOV 21 2015
MAIN FORECAST PROBLEM WILL BE TEMPERATURES. SATELLITE SHOWING A
SOMEWHAT AMPLIFIED BUT STILL PROGRESSIVE FLOW FROM THE PACIFIC INTO
THE WESTERN ATLANTIC.
AT JET LEVEL...THE ECMWF STARTED OUT BETTER THAN THE REMAINING
OUTPUT. AT MID LEVELS...ALL MODELS STARTED OUT WELL WITH MAYBE THE
GFS/CANADIAN/UKMET HAVING AN EVER SO SLIGHT ADVANTAGE. THE ECMWF WAS
DOING A LITTLE BETTER ON THE SURFACE WIND AND PRESSURE FIELD. THE
ECMWF WAS DOING A LITTLE BETTER THAN THE GFS/CANADIAN ON THE LOW
LEVEL THERMAL FIELD.
TODAY/TONIGHT...AREA REMAINS IN SUBSIDENCE FROM UPPER JET AS MID
LEVEL RIDGE BUILDS IN. COLD AND DRY AIR POURING INTO THE AREA.
SATELLITE STILL SHOWING A NARROW BUT SUBSTANTIAL SNOWFIELD FROM THE
SOUTHWEST CORNER TO NEAR THE NORTHEAST CORNER. BIG DIFFERENCES IN
TEMPERATURES BETWEEN WHERE THERE IS NO SNOW AND THIS SNOW FIELD.
SIGNIFICANT CLEARING SHOULD OCCUR. CONSIDERING THE CHANGE IN AIR
MASS AND YESTERDAYS TEMPERATURES...MADE ONLY SLIGHT ADJUSTMENTS TO
THE TEMPERATURES WITH THE COOLEST IN THE SNOWFIELD. LIGHT WESTERLY
WINDS TONIGHT. SO WOULD EXPECT THE SNOWFIELD AND LOCATIONS JUST
DOWNSTREAM OF THE SNOWFIELD TO BE THE COLDEST.
SUNDAY/SUNDAY NIGHT...SUBSIDENCE AND RIDGING CONTINUE/STRENGTHENS
ACROSS THE AREA. AIR MASS WARMS AND DO HAVE DOWNSLOPE WINDS OVER THE
ENTIRE AREA. HOWEVER THOSE WINDS LOOK TO BE BLOWING ALONG THE LENGTH
OF THAT SNOWFIELD. NOT SURE HOW MUCH THE AIR MASS WILL BE
MODIFIED...ESPECIALLY IN THE SNOWFIELD. TENDED TO WARM TEMPERATURES
FROM THE PREVIOUS FORECAST IN LOCATIONS THAT WILL NOT BE AFFECTED BY
THE SNOWFIELD. MADE LITTLE TO NO ADJUSTMENTS FOR THE SNOWFIELD
AFFECTED AREAS.
WINDS LOOK TO BE A LITTLE STRONGER DURING THE NIGHT WITH MORE WARM
AIR ADVECTION OCCURRING. SO TEMPERATURES WARMER AND MORE UNIFORM.
MONDAY/MONDAY NIGHT...WEAK RIDGING/ZONAL FLOW ALOFT IS OVER THE
REGION. MODELS ARE IN DISAGREEMENT IN WHAT TO DO WITH THE WIND
FIELD. IT IS ALMOST LIKE SOME OF THE MODELS PUSH A WEAK BOUNDARY
INTO THE AREA. OVERALL THE WIND FIELD LOOKS LIGHT WHICH IS NOT
CONDUCIVE TO A BIG WARMUP. THIS COMBINED WITH THE SNOWFIELD MAKES
THE TEMPERATURES A LITTLE MORE DIFFICULT. AGAIN ONLY MADE SLIGHT
ADJUSTMENTS TO THE HIGH TEMPERATURES.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 145 AM MST SAT NOV 21 2015
TUESDAY-WEDNESDAY...CLOSED UPPER LOW DEEPENING OVER THE WESTERN US
RESULTS IN DEEP SW FLOW ACROSS OUR CWA AND GOOD WAA. DEEP DRY AIR
MASS WILL PREVENT ANY SHOWER/THUNDERSTORM DEVELOPMENT DESPITE
INCREASING INSTABILITY AND WEAK SHORTWAVE TROUGHS EMBEDDED WITHIN SW
FLOW. CURRENTLY EXPECTED THESE PERIOD TO REMAIN DRY WITH ABOVE
NORMAL TEMPERATURES BOTH DAYS. I CONTINUED TO ACCOUNT FOR SNOW
FIELD...THOUGH ITS IMPACT SHOULD CONTINUE TO DECREASE AS FURTHER
MELTING OCCURS SUNDAY/MONDAY.
WEDNESDAY NIGHT-THURSDAY...MESSY AND COLD WEATHER PATTERN POSSIBLE
FOR THANKSGIVING AS UPPER LOW BEGINS TO SHIFT EASTWARD AND ARCTIC
FRONT DROPS SOUTH ACROSS THE PLAINS. EXPERIENCE WITH SIMILAR EVENTS
LEADS ME TO FAVOR FASTER FRONTAL TIMING AND COLDER
TEMPERATURES...AND I TRENDED THIS WAY. WITH EXTENSIVE CLOUD
COVER/POSSIBLE PRECIPITATION WE MAY NOT SEE HIGHS OUT OF THE TEENS.
IT IS STILL FAR ENOUGH OUT THAT I ONLY MADE INCREMENTAL ADJUSTMENTS
DOWNWARD ON TEMPERATURES FROM CONSENSUS BLEND. MODELS ARE SHOWING
BEST PRECIP SIGNAL WED NIGHT THROUGH THURSDAY.
TEMPERATURE/MOISTURE PROFILES WED NIGHT AND THURSDAY FAVOR A MIX
OF FREEZING RAIN (MAYBE A SHORT PERIOD OF SLEET) WITH SATURATED
LAYER ABOUT 3-5KFT DEEP 0C TO -8C UNTIL AROUND SUNSET THURSDAY.
AS I MENTIONED...I COULD SEE BL TEMPS COOLER THAN PROJECTED AND
THIS MIGHT FAVOR A TRANSITION TO MAINLY SNOW EARLIER ACROSS THE
NORTH/NORTHWEST. I KEPT MENTION OF FREEZING DRIZZLE/SNOW WHERE
DEEPER COLD LAYER IS MOST LIKELY WITH RAIN/FREEZING RAIN IN OUR
SOUTH/SOUTHEAST. AT THIS TIME IT APPEARS ANY ACCUMULATIONS SHOULD
BE LIGHT IF WE DO SEE ICE OR SNOW. CONDITIONS WILL BE SLICK AND
COLD EITHER WAY THOUGH...SO WE WILL NEED TO CONTINUE MONITORING
THIS AS WE MAY END UP NEEDING SOME FLAVOR OF ADVISORY.
FRIDAY...EVOLUTION OF UPPER LOW AND EROSION OF SHALLOW COLD AIR
MASS IS LESS CERTAIN DURING THESE PERIODS AND MODELS ARE SHOWING
MUCH MORE VARIANCE IN HEIGHT PATTERNS AND A LESS CONSISTENT PRECIP
SIGNAL. THERE IS SIGNIFICANT ENSEMBLE SPREAD WITH GEFS.
DETERMINISTIC GUIDANCE ISNT ANY BETTER WITH ECMWF SHOWING CLOSED
LOW REMAINING WEST AND LARGE SCALE TROUGH ELONGATING ACROSS THE
PLAINS...WHILE GFS/GEM BOTH BREAK DOWN CLOSED CENTER AND PROGRESS
THIS UPPER LOW QUICKLY ACROSS THE PLAINS. EITHER SOLUTION WILL
FAVOR COLD TEMPERATURES FRIDAY...HOWEVER THESE VARIANCES DO LEAD
TO LESS CONFIDENCE IN PRECIP CHANCES BEYOND THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 456 AM MST SAT NOV 21 2015
FOR KGLD...FLURRIES WITH MVFR CEILINGS WILL OCCUR THROUGH THE
FIRST COUPLE HOURS OF THE FORECAST. AFTER THAT...VFR CONDITIONS
ARE EXPECTED THROUGH THE PERIOD. NORTHWEST WINDS AT 5 TO AROUND 10
KNOTS WILL GRADUALLY SHIFT TO THE WEST AND SOUTHWEST THROUGH THE
PERIOD.
FOR KMCK...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD.
NORTHWEST WINDS OF 5 TO NEAR 10 KNOTS WILL GRADUALLY SHIFT TO THE
WEST AND SOUTHWEST THROUGH THE PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...BULLER
LONG TERM...DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1037 PM EST SUN NOV 22 2015
.SYNOPSIS...
LOW PRESSURE WILL DEVELOP ALONG A STATIONARY FRONT EAST OF THE
REGION TONIGHT AND MOVE NORTHEAST MONDAY TOWARD NOVA SCOTIA. HIGH
PRESSURE WILL BUILD TOWARD THE REGION MON NIGHT INTO TUE.
&&
.NEAR TERM /THROUGH MONDAY/...
1040 PM UPDATE...
QUICK UPDATE TO GRIDS TO WARM T/TD VALUES AS THEY RMN SLOW TO
FALL. PER LATEST HRRR DATA 0C 925MB TEMP LINE IS DOWN TO HUL AS OF
04Z AND EXPECT THEY WL BEGIN TO SWITCH OVER TO SNOW BTWN 05 AND
06Z PER LATEST HRRR SNDG. INTERESTING TO NOTE THAT BGR IS
REPORTING RA/SN BUT NO OTHER STATION AROUND THEM IS. THINK THAT
CURRENT FCST IS STILL ON TRACK SO JUST MADE MINOR TWEAKS TO WX
GRIDS WITH NO REAL CHANGE IN OVERALL THINKING.
PREV DISCUSSIONS BLO...
850 PM UPDATE...
SFC LOW CURRENTLY SITTING OFF OF THE VIRGINIA CAPES AND RIDING UP
ALONG FRONTAL BOUNDARY JUST OFFSHORE. FAIRLY TIGHT GRADIENT EXISTS
BTWN PCPN AND NO PCPN AS EXPECTED WITH HUL HVG RAIN AND PQI
NOTHING IN THE WAY OF PCPN. RADAR POPUP SKEW T IS SHOWING HUL
ISOTHERMAL FROM ABOUT 900MB UP WITH BLYR ABV ZERO ALL THE WAY BACK
TO ALLAGASH. THIS AGREES WELL WITH LATEST HRRR DATA THUS HV
ADJUSTED WX GRIDS BASED ON HRRR FCST DATA THRU THE MRNG.
EXPECT THAT PCPN WL BE HIT AND MISS IN NATURE FROM ABOUT PQI
NORTHWARD BUT IF IT CAN GET THIS AFTN NORTH IT SHOULD NOT BEGIN TO
MIX WITH SNOW UNTIL CLOSE TO 03Z. PCPN SHUD GRADUALLY SPREAD NORTH
AFT ABOUT 05Z AS LOW TRACKS CLOSER TO GULF OF MAINE IN COMBINATION
WITH RFQ OF H3 SPEED MAX GETTING EVER CLOSER TO CWA. THIS WL
BRING THE BEST CHC FOR ACCUMULATING SNOW FOR NORTHERN AREAS BFR
DAYBREAK.
AT THIS TIME IT APPEARS THAT QPF AMNTS WL BE LIGHT FOR NRN ZONES
AND WL BE HARD-PRESSED TO SEE MORE THAN AN INCH OF SNOW AND SLEET
FOR AREAS NORTH OF A MILLINOCKET TO HOULTON LINE. THUS WL CONTINUE
WITH MENTION OF AMNTS UP TO AN INCH BY MRNG. FURTHER TO THE SOUTH
HV LOWERED STORM TOTAL SNOW AMNTS BY ARND AN INCH AS IT APPEARS
THAT CLD AIR WL TAKE LONGER TO WRAP IN BHND LOW ESPECIALLY ALONG
THE COAST. HWVR, WL CONT WITH WINTER WX ADVISORY AS STILL
EXPECTING WIDESPREAD 1-4 INCHES ON TOP OF SLEET THAT FALLS. ALL
THIS WL FALL ON ALREADY WET ROADWAYS WHICH WL QUICKLY ICE OVER AS
TEMPS FALL DRG THE DAY TOMORROW. HIGHEST SNOW TOTALS LOOK TO OCCUR
ACRS NRN WASHINGTON CNTY AS WELL AS PARTS OF SE AROOSTOOK CNTY.
PREV DISCUSSION BLO...
LONGER RANGE MODELS HAVE COME INTO BETTER CONSENSUS FOR THIS
AFTN`S FCST UPDATE REGARDING THE COASTAL LOW EVENT MOVG NE FROM
OFF THE MID ATLC STATES TNGT TOWARD THE CNTRL NOVA SCOTIA MON
AFTN. THE 12Z DTMNSTC ECMWF BACKED OFF FROM BEING FURTHER N LIKE
THE PRIOR 00Z ECMWF RUN...BOTH WITH THE PSN OF THE SFC LOW AND
HEAVIER QPF FURTHER N INTO CNTRL AND NRN PTNS OF THE FA. THE
FURTHER SE TRACK OF THE 12Z GFS AND CANGEM MODELS SEEMS TO BE
INITIALLY VERIFYING BASED ON THE TRAJECTORIES OF THE WRN EDGE
OF RADAR REF MOVG INTO THE MID COAST AND DOWNEAST PTNS OF ME LATE
THIS AFTN.
BASED ON THE CURRENT FCST OF THE LOW TRACK...MILD AIR CURRENTLY
OVR THE FA WILL BE REPLACED BY SIG COLDER AIR MOVG E FROM QB AS
THE LOW HELPS ADVECT IT SE INTO OUR FA LATER TNGT INTO MON MORN.
TEMPS WILL FALL FAIRLY QUICKLY...FIRST ACROSS THE NW HLF LATER
THIS EVE THEN SPREADING SE THRU THE REST OF THE FA LATE TNGT INTO
MON MORN...RESULTING IN PRECIP CHGNG FROM RN TO SN NW TO SE ACROSS
THE FA DURG THIS TM...PERHAPS ACCOMPANIED BY A BRIE PD OF SLEET
BASED ON SREF PRECIP TYPES AND FCST SOUNDINGS. THE TRICKY PART OF
THIS FCST WILL BE OVR E CNTRL AND DOWNEAST PTNS OF THE FA WHERE
SIG PRECIP RATES MAY STILL BE GOING ON WHEN TEMPS APCH OR FALL
BELOW FZG...MEANING LCTNS CHGNG TO SNOW LATEST TNGT N OF THE
IMMEDIATE DOWNEAST COAST COULD RECEIVE THE MOST SN DUE TO GREATER
REMAINING QPF LEFT WITH THIS EVENT. SPEAKING OF QPF... STORM TOTAL
QPF WILL RANGE FROM NEAR ZERO OVR THE FAR NW TO NEARLY 2.00 INCHES
OVR THE EXTREME SE. FOR NOW...OUR OFFICIAL MAX SNFL TOTALS ARE 3
TO 5 INCHES OVR NRN AND CNTRL WASHINGTON COUNTIES WITH LESSER
AMOUNTS ELSEWHERE...BUT GIVEN UNCERTAINTIES OF CHGOVR TM AND
POTENTIAL INTENSITY OF SNFL AFT THE CHGOVR...CONFIDENCE WITH MAX
AMOUNTS OVR THIS PTN OF THE FA IS NOT HIGH WITH SIG MORE OR LESS
POSSIBLE. LATER SHIFTS WILL NEED TO MONITOR OBSVD AND MODEL TRENDS
WITH THIS EVENT.
IN ANY EVENT...SN WILL TAPER TO SCT SN SHWRS N AND RN/SN SHWRS
CNTRL AND DOWNEAST MON AFTN AND THEN END BY LATE IN THE DAY. BOTH
LOWS TNGT AND HI TEMPS MON WILL BE COLDER...SPCLY OVR CNTRL AND
DOWNEAST PTNS OF THE FA.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
THE SHORT TERM WILL FEATURE FAIR WEATHER UNDER A BUILDING RIDGE,
THOUGH AT LEAST TUE WILL BE A BIT COOLER THAN NORMAL. AT THE
BEGINNING OF THE SHORT TERM, THE BULK OF THE PRECIP IS EXPECTED TO
HAVE DEPARTED TO THE EAST. HOWEVER, WITH THE BASE OF THE UPR TROF
SWINGING OVER THE AREA MON NIGHT, CAN`T RULE OUT SOME LINGERING
CLOUDS AND A FEW LIGHT SN SHWRS IN THE FAR NRN CWA, AS WAS
REFLECTED IN A FEW MODELS.
BEYOND THAT, HIGH PRESSURE AND RIDGING TUE THRU WED WILL BRING
PARTLY TO MOSTLY SUNNY SKIES TO THE STATE. COLD AIR DRAWN IN
BEHIND THE LOW MON NIGHT AND GOOD RADIATIONAL COOLING WILL SET
THE STAGE FOR SOME OF THE COLDEST TEMPS IN THE CWA THUS FAR THIS
COLD SEASON MON AND TUE NIGHTS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL GRADUALLY SLIDE OFF THE EAST COAST THURSDAY,
KEEPING CONDITIONS DRY FOR THANKSGIVING DAY. THIS WILL ALSO PLACE
THE REGION UNDER SOUTHWEST FLOW ON THE BACKSIDE OF THE HIGH,
ALLOWING TEMPERATURES TO WARM INTO THE MID AND UPPER 40S. HOWEVER,
LOW PRESSURE MOVING BY TO OUR NORTH WILL SLOWLY DRAG A COLD FRONT
EASTWARD ACROSS THE EASTERN US/CANADA THURSDAY NIGHT THROUGH
FRIDAY. THERE`S SOME DISAGREEMENT AMONGST THE LONGER-RANGE MODELS
ON THE EXACT TIMING OF THIS FRONT AND ITS PRECIPITATION, BUT THE
HIGHEST THREAT FOR FRONTAL PASSAGE LOOKS TO OCCUR SOMETIME LATE
FRIDAY THROUGH SATURDAY. IF THE FRONT HOLDS OFF UNTIL FRIDAY
NIGHT, EXPECT WE`LL SEE VERY MILD TEMPERATURES FOR THE DAY AFTER
THANKSGIVING AS HIGHS TOP OUT IN THE UPPER 40S TO LOWER 50S.
HOWEVER, IF THE FRONT MOVES THROUGH A LITTLE FASTER (SIMILAR TO
THE GFS SOLUTION), NORTHERN MAINE MAY HAVE A COOLER AND WETTER
FRIDAY THAN IS CURRENTLY IN THE FORECAST. REGARDLESS, EXPECT MUCH
COLDER AIR WILL MOVE IN BEHIND THE FRONT. SUNDAY LOOKS TO BE THE
COLDEST DAY OF THE WEEKEND AT THE MOMENT, WITH HIGHS ONLY IN THE
20S IN THE NORTH, AND LOWS IN THE TEENS.
&&
.AVIATION /04Z MONDAY THROUGH FRIDAY/...
NEAR TERM: IFR EXPECTED NEXT 24 HOURS AT MOST TERMINALS IN
RAIN/SNOW. EXCEPTION WILL BE FVE WHERE SITE WILL MOST LIKELY BE
AFFECTED BY IFR CIGS WITH PCPN REMAINING TO THE SOUTH. STILL SOME
QUESTION AS TO HOW MUCH CAR AND PQI WILL SEE WITH REGARD TO PTYPE
AS THEY WILL BE ON NORTHERN EDGE OF PCPN SHIELD. HUL WILL SEE
RA/SN MIX AROUND 03Z THEN OVER TO ALL SNOW AFTER 06Z. BGR CAN BE
EXPECTED TO BE RA/SN AFTER 04Z THEN SWITCHING TO SNOW BY 08Z. BHB
WILL BE LATEST TO SEE CHANGEOVER TO RA/SN BY 09Z AND ALL SNOW
AROUND 10Z. BY 18Z MON BHB, BGR AND HUL WILL SEE IMPROVEMENT TO
VFR CIGS WITH FVE, CAR AND PQI VFR BY 15Z. NW WINDS WILL BE GUSTY
DURING THE DAY AT 15G25KTS.
SHORT TERM: ASIDE FROM THE CHC FOR SOME MVFR CIGS AND ISO SN
SHWRS FOR KFVE BEFORE 09ZTUE, ALL TERMINALS ARE EXPECTED TO HAVE
VFR CIGS AND VIS THROUGH WED EVENING. VFR CONDITIONS WILL THEN
CONTINUE THROUGH FRIDAY, THOUGH MVFR CEILINGS WILL BE POSSIBLE AT
THE NORTHERN TERMINALS FRIDAY AFTERNOON AS A COLD FRONT APPROACHES
FROM THE NORTH.
&&
.MARINE...
NEAR TERM: E TO NE WINDS WILL INCREASE TO SCA CRITERIA FOR THE
INNER BAY/HARBOR MZ THIS EVE AND GALES (IN GUSTS) OVR THE OUTER
MZS LATE TNGT...BACKING TO THE N AS THEY CONTINUE INTO MON. GALES
OVR THE OUTER MZS WILL NEED TO BE TRANSITIONED TO AN SCA LATER MON
AFTN. KEPT CLOSE TO WW3 WV GUIDANCE FOR FCST WV HTS.
SHORT TERM: SCA WIND GUSTS AND SEAS LKLY ONGOING OFFSHORE AT THE
START OF THE SHORT TERM. WILL CONTINUE TUE AM BEFORE GRADUALLY
DIMINISHING TUE PM AS HIGH PRES BUILDS INTO THE AREA.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 11 AM EST MONDAY FOR MEZ006-011-
015.
WINTER WEATHER ADVISORY UNTIL 1 PM EST MONDAY FOR MEZ016-017-
029-030-032.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST MONDAY FOR ANZ052.
GALE WARNING UNTIL 1 PM EST MONDAY FOR ANZ050-051.
&&
$$
NEAR TERM...FARRAR/VJN
SHORT TERM...KREDENSOR
LONG TERM...HASTINGS
AVIATION...FARRAR/VJN/KREDENSOR
MARINE...FARRAR/VJN/KREDENSOR
AREA FORECAST DISCUSSION
NWS CARIBOU ME
847 PM EST SUN NOV 22 2015
.SYNOPSIS...
LOW PRESSURE WILL DEVELOP ALONG A STATIONARY FRONT EAST OF THE
REGION TONIGHT AND MOVE NORTHEAST MONDAY TOWARD NOVA SCOTIA. HIGH
PRESSURE WILL BUILD TOWARD THE REGION MON NIGHT INTO TUE.
&&
.NEAR TERM /THROUGH MONDAY/...
850 PM UPDATE...
SFC LOW CURRENTLY SITTING OFF OF THE VIRGINIA CAPES AND RIDING UP
ALONG FRONTAL BOUNDARY JUST OFFSHORE. FAIRLY TIGHT GRADIENT EXISTS
BTWN PCPN AND NO PCPN AS EXPECTED WITH HUL HVG RAIN AND PQI
NOTHING IN THE WAY OF PCPN. RADAR POPUP SKEW T IS SHOWING HUL
ISOTHERMAL FROM ABOUT 900MB UP WITH BLYR ABV ZERO ALL THE WAY BACK
TO ALLAGASH. THIS AGREES WELL WITH LATEST HRRR DATA THUS HV
ADJUSTED WX GRIDS BASED ON HRRR FCST DATA THRU THE MRNG.
EXPECT THAT PCPN WL BE HIT AND MISS IN NATURE FROM ABOUT PQI
NORTHWARD BUT IF IT CAN GET THIS AFTN NORTH IT SHOULD NOT BEGIN TO
MIX WITH SNOW UNTIL CLOSE TO 03Z. PCPN SHUD GRADUALLY SPREAD NORTH
AFT ABOUT 05Z AS LOW TRACKS CLOSER TO GULF OF MAINE IN COMBINATION
WITH RFQ OF H3 SPEED MAX GETTING EVER CLOSER TO CWA. THIS WL
BRING THE BEST CHC FOR ACCUMULATING SNOW FOR NORTHERN AREAS BFR
DAYBREAK.
AT THIS TIME IT APPEARS THAT QPF AMNTS WL BE LIGHT FOR NRN ZONES
AND WL BE HARD-PRESSED TO SEE MORE THAN AN INCH OF SNOW AND SLEET
FOR AREAS NORTH OF A MILLINOCKET TO HOULTON LINE. THUS WL CONTINUE
WITH MENTION OF AMNTS UP TO AN INCH BY MRNG. FURTHER TO THE SOUTH
HV LOWERED STORM TOTAL SNOW AMNTS BY ARND AN INCH AS IT APPEARS
THAT CLD AIR WL TAKE LONGER TO WRAP IN BHND LOW ESPECIALLY ALONG
THE COAST. HWVR, WL CONT WITH WINTER WX ADVISORY AS STILL
EXPECTING WIDESPREAD 1-4 INCHES ON TOP OF SLEET THAT FALLS. ALL
THIS WL FALL ON ALREADY WET ROADWAYS WHICH WL QUICKLY ICE OVER AS
TEMPS FALL DRG THE DAY TOMORROW. HIGHEST SNOW TOTALS LOOK TO OCCUR
ACRS NRN WASHINGTON CNTY AS WELL AS PARTS OF SE AROOSTOOK CNTY.
PREV DISCUSSION BLO...
LONGER RANGE MODELS HAVE COME INTO BETTER CONSENSUS FOR THIS
AFTN`S FCST UPDATE REGARDING THE COASTAL LOW EVENT MOVG NE FROM
OFF THE MID ATLC STATES TNGT TOWARD THE CNTRL NOVA SCOTIA MON
AFTN. THE 12Z DTMNSTC ECMWF BACKED OFF FROM BEING FURTHER N LIKE
THE PRIOR 00Z ECMWF RUN...BOTH WITH THE PSN OF THE SFC LOW AND
HEAVIER QPF FURTHER N INTO CNTRL AND NRN PTNS OF THE FA. THE
FURTHER SE TRACK OF THE 12Z GFS AND CANGEM MODELS SEEMS TO BE
INITIALLY VERIFYING BASED ON THE TRAJECTORIES OF THE WRN EDGE
OF RADAR REF MOVG INTO THE MID COAST AND DOWNEAST PTNS OF ME LATE
THIS AFTN.
BASED ON THE CURRENT FCST OF THE LOW TRACK...MILD AIR CURRENTLY
OVR THE FA WILL BE REPLACED BY SIG COLDER AIR MOVG E FROM QB AS
THE LOW HELPS ADVECT IT SE INTO OUR FA LATER TNGT INTO MON MORN.
TEMPS WILL FALL FAIRLY QUICKLY...FIRST ACROSS THE NW HLF LATER
THIS EVE THEN SPREADING SE THRU THE REST OF THE FA LATE TNGT INTO
MON MORN...RESULTING IN PRECIP CHGNG FROM RN TO SN NW TO SE ACROSS
THE FA DURG THIS TM...PERHAPS ACCOMPANIED BY A BRIE PD OF SLEET
BASED ON SREF PRECIP TYPES AND FCST SOUNDINGS. THE TRICKY PART OF
THIS FCST WILL BE OVR E CNTRL AND DOWNEAST PTNS OF THE FA WHERE
SIG PRECIP RATES MAY STILL BE GOING ON WHEN TEMPS APCH OR FALL
BELOW FZG...MEANING LCTNS CHGNG TO SNOW LATEST TNGT N OF THE
IMMEDIATE DOWNEAST COAST COULD RECEIVE THE MOST SN DUE TO GREATER
REMAINING QPF LEFT WITH THIS EVENT. SPEAKING OF QPF... STORM TOTAL
QPF WILL RANGE FROM NEAR ZERO OVR THE FAR NW TO NEARLY 2.00 INCHES
OVR THE EXTREME SE. FOR NOW...OUR OFFICIAL MAX SNFL TOTALS ARE 3
TO 5 INCHES OVR NRN AND CNTRL WASHINGTON COUNTIES WITH LESSER
AMOUNTS ELSEWHERE...BUT GIVEN UNCERTAINTIES OF CHGOVR TM AND
POTENTIAL INTENSITY OF SNFL AFT THE CHGOVR...CONFIDENCE WITH MAX
AMOUNTS OVR THIS PTN OF THE FA IS NOT HIGH WITH SIG MORE OR LESS
POSSIBLE. LATER SHIFTS WILL NEED TO MONITOR OBSVD AND MODEL TRENDS
WITH THIS EVENT.
IN ANY EVENT...SN WILL TAPER TO SCT SN SHWRS N AND RN/SN SHWRS
CNTRL AND DOWNEAST MON AFTN AND THEN END BY LATE IN THE DAY. BOTH
LOWS TNGT AND HI TEMPS MON WILL BE COLDER...SPCLY OVR CNTRL AND
DOWNEAST PTNS OF THE FA.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
THE SHORT TERM WILL FEATURE FAIR WEATHER UNDER A BUILDING RIDGE,
THOUGH AT LEAST TUE WILL BE A BIT COOLER THAN NORMAL. AT THE
BEGINNING OF THE SHORT TERM, THE BULK OF THE PRECIP IS EXPECTED TO
HAVE DEPARTED TO THE EAST. HOWEVER, WITH THE BASE OF THE UPR TROF
SWINGING OVER THE AREA MON NIGHT, CAN`T RULE OUT SOME LINGERING
CLOUDS AND A FEW LIGHT SN SHWRS IN THE FAR NRN CWA, AS WAS
REFLECTED IN A FEW MODELS.
BEYOND THAT, HIGH PRESSURE AND RIDGING TUE THRU WED WILL BRING
PARTLY TO MOSTLY SUNNY SKIES TO THE STATE. COLD AIR DRAWN IN
BEHIND THE LOW MON NIGHT AND GOOD RADIATIONAL COOLING WILL SET
THE STAGE FOR SOME OF THE COLDEST TEMPS IN THE CWA THUS FAR THIS
COLD SEASON MON AND TUE NIGHTS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL GRADUALLY SLIDE OFF THE EAST COAST THURSDAY,
KEEPING CONDITIONS DRY FOR THANKSGIVING DAY. THIS WILL ALSO PLACE
THE REGION UNDER SOUTHWEST FLOW ON THE BACKSIDE OF THE HIGH,
ALLOWING TEMPERATURES TO WARM INTO THE MID AND UPPER 40S. HOWEVER,
LOW PRESSURE MOVING BY TO OUR NORTH WILL SLOWLY DRAG A COLD FRONT
EASTWARD ACROSS THE EASTERN US/CANADA THURSDAY NIGHT THROUGH
FRIDAY. THERE`S SOME DISAGREEMENT AMONGST THE LONGER-RANGE MODELS
ON THE EXACT TIMING OF THIS FRONT AND ITS PRECIPITATION, BUT THE
HIGHEST THREAT FOR FRONTAL PASSAGE LOOKS TO OCCUR SOMETIME LATE
FRIDAY THROUGH SATURDAY. IF THE FRONT HOLDS OFF UNTIL FRIDAY
NIGHT, EXPECT WE`LL SEE VERY MILD TEMPERATURES FOR THE DAY AFTER
THANKSGIVING AS HIGHS TOP OUT IN THE UPPER 40S TO LOWER 50S.
HOWEVER, IF THE FRONT MOVES THROUGH A LITTLE FASTER (SIMILAR TO
THE GFS SOLUTION), NORTHERN MAINE MAY HAVE A COOLER AND WETTER
FRIDAY THAN IS CURRENTLY IN THE FORECAST. REGARDLESS, EXPECT MUCH
COLDER AIR WILL MOVE IN BEHIND THE FRONT. SUNDAY LOOKS TO BE THE
COLDEST DAY OF THE WEEKEND AT THE MOMENT, WITH HIGHS ONLY IN THE
20S IN THE NORTH, AND LOWS IN THE TEENS.
&&
.AVIATION /01Z MONDAY THROUGH FRIDAY/...
NEAR TERM: IFR EXPECTED NEXT 24 HOURS AT MOST TERMINALS IN
RAIN/SNOW. EXCEPTION WILL BE FVE WHERE SITE WILL MOST LIKELY BE
AFFECTED BY IFR CIGS WITH PCPN REMAINING TO THE SOUTH. STILL SOME
QUESTION AS TO HOW MUCH CAR AND PQI WILL SEE WITH REGARD TO PTYPE
AS THEY WILL BE ON NORTHERN EDGE OF PCPN SHIELD. HUL WILL SEE
RA/SN MIX AROUND 03Z THEN OVER TO ALL SNOW AFTER 06Z. BGR CAN BE
EXPECTED TO BE RA/SN AFTER 04Z THEN SWITCHING TO SNOW BY 08Z. BHB
WILL BE LATEST TO SEE CHANGEOVER TO RA/SN BY 09Z AND ALL SNOW
AROUND 10Z. BY 18Z MON BHB, BGR AND HUL WILL SEE IMPROVEMENT TO
VFR CIGS WITH FVE, CAR AND PQI VFR BY 15Z. NW WINDS WILL BE GUSTY
DURING THE DAY AT 15G25KTS.
SHORT TERM: ASIDE FROM THE CHC FOR SOME MVFR CIGS AND ISO SN
SHWRS FOR KFVE BEFORE 09ZTUE, ALL TERMINALS ARE EXPECTED TO HAVE
VFR CIGS AND VIS THROUGH WED EVENING. VFR CONDITIONS WILL THEN
CONTINUE THROUGH FRIDAY, THOUGH MVFR CEILINGS WILL BE POSSIBLE AT
THE NORTHERN TERMINALS FRIDAY AFTERNOON AS A COLD FRONT APPROACHES
FROM THE NORTH.
&&
.MARINE...
NEAR TERM: E TO NE WINDS WILL INCREASE TO SCA CRITERIA FOR THE
INNER BAY/HARBOR MZ THIS EVE AND GALES (IN GUSTS) OVR THE OUTER
MZS LATE TNGT...BACKING TO THE N AS THEY CONTINUE INTO MON. GALES
OVR THE OUTER MZS WILL NEED TO BE TRANSITIONED TO AN SCA LATER MON
AFTN. KEPT CLOSE TO WW3 WV GUIDANCE FOR FCST WV HTS.
SHORT TERM: SCA WIND GUSTS AND SEAS LKLY ONGOING OFFSHORE AT THE
START OF THE SHORT TERM. WILL CONTINUE TUE AM BEFORE GRADUALLY
DIMINISHING TUE PM AS HIGH PRES BUILDS INTO THE AREA.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 11 AM EST MONDAY FOR MEZ006-011-
015.
WINTER WEATHER ADVISORY FROM 1 AM TO 1 PM EST MONDAY FOR
MEZ016-017-029-030-032.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST MONDAY FOR ANZ052.
GALE WARNING FROM 1 AM TO 1 PM EST MONDAY FOR ANZ050-051.
&&
$$
NEAR TERM...FARRAR/VJN
SHORT TERM...KREDENSOR
LONG TERM...HASTINGS
AVIATION...FARRAR/VJN/KREDENSOR
MARINE...FARRAR/VJN/KREDENSOR
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1238 PM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL CREST OVER THE REGION TODAY. LOW PRESSURE WILL
MOVE NORTHWEST OF THE AREA ON SUNDAY WITH SOME RAIN. A SECOND
AREA OF LOW PRESSURE WILL LIFT ACROSS THE GULF OF MAINE SUNDAY
NIGHT AND THEN INTO THE MARITIMES ON MONDAY WITH MUCH COLDER AIR.
&&
.NEAR TERM /THROUGH TONIGHT/...
1240 PM UPDATE...
SKIES ARE GRADUALLY CLOUDING UP ACRS THE NORTH THIS AFTN AS
EXPECTED. MOSUNNY SKIES THIS MRNG ALLOWED TEMPS TO CLIMB ABV 40F
AT MOST LOCALES ACRS THE NORTH AS OF 17Z THUS HV BUMPED MAXES UP
ABOUT 2 DEGREES FOR TDA. NO OTHER CHGS NEEDED WITH THIS UPDATE.
PREV DISCUSSION BLO...
HIGH PRESSURE WILL BUILD IN FROM THE WEST THIS MORNING WITH
CLEARING EARLY TODAY. THE HIGH PRESSURE SYSTEM WILL CREST OVER THE
REGION TODAY THEN MOVE OFF TO THE EAST THIS EVENING. WEAK LOW
PRESSURE WILL DEVELOP OVER THE GULF OF MAINE BEHIND THE DEPARTING
LOW AND SPREAD RAIN AND SNOW INTO NEW BRUNSWICK TONIGHT. INTENSE
LOW PRESSURE WILL MOVE INTO THE GREAT LAKES TONIGHT THEN MOVE INTO
SOUTHEASTERN QUEBEC PROVINCE EARLY SUNDAY.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
AN INTERESTING SETUP FOR SUNDAY NIGHT INTO EARLY MONDAY.
A FRONTAL SYSTEM IS FORECAST TO SLIDE ACROSS THE AREA ON SUNDAY
W/SOME SHOWERS OR LIGHT RAIN PULLING OUT OF THE AREA IN THE
MORNING. THE 2ND BATCH OF PRECIP IN THE FORM OF RAIN IS EXPECTED
TO SET UP LATER IN DAY AS LOW PRES DEVELOPS OFF THE SOUTHERN NEW
ENGLAND COAST AND LIFTS NNE. THE AREAS THAT WILL SEE MEASURABLE
QPF WILL BE ACROSS THE EASTERN 1/2 OF THE CWA WHERE THE BEST
FORCING AND LLVL CONVERGENCE WILL BE LOCATED. AS THE LOW LIFTS TO
NNE AND THE UPPER TROF DIGS SOME AS IT SWINGS INTO THE NE, COLDER
AIR WILL START TO FILTER INTO THE REGION. THE ECMWF AND GFS ARE IN
AGREEMENT W/THE COLDER AIR COMING IN BY THE EVENING WHILE THE
CANADIAN GEM & NAM HOLD THE COLDER AIR BACK BY 3-6 HRS. DECIDED TO
GO W/A CONSENSUS BLEND OF THE GUIDANCE FOR THIS PACKAGE SHOWING
RAIN GOING OVER TO A PERIOD OF SNOW BY 11 PM OR SO. ALL THE
GUIDANCE IS IN AGREEMENT THAT THE BULK OF THE QPF WILL BE ACROSS
THE EASTERN 3RD OF THE CWA SAY FROM FROM HOULTON DOWN INTO HANCOCK
AND WASHINGTON COUNTY W/UP AROUND 0.50 INCHES. ATTM, IF THERE IS
TO BE ANY SNOWFALL ACCUMULATION, IT WILL BE ACROSS EASTERN
WASHINGTON COUNTY W/A SLUSHY INCH POSSIBLE BEFORE THINGS WIND DOWN
MONDAY MORNING. TEMPERATURES ARE FORECAST TO DROP DOWN INTO THE
LOWER 30S ACROSS EASTERN AREAS AFTER MIDNIGHT W/MID AND UPPER 20S
BACK ACROSS THE W AND NW AREAS.
THE LOW IS FORECAST TO QUICKLY LIFT ACROSS THE MARITIMES ON MONDAY
W/CAA POURING INTO THE REGION AND DRIER CONDITIONS. THERE IS SOME
CONCERN THE CLOUDS ACROSS NORTHERN AND EASTERN MAINE MIGHT HANG ON
THROUGH MONDAY W/A NNW FLOW COMING IN OFF THE OPEN ST. LAWRENCE.
THE GFS SOUNDINGS HINT AT THIS TO BE POSSIBLE W/SOME MOISTURE
SHOWING UP BELOW 3000 FT. THIS SETUP SIMILAR TO THIS SCENARIO TOOK
PLACE LAST WEEK WHEN A CLOUD DECK BELOW 2500 FT HUNG ON LONGER
THAN ANTICIPATED. TEMPERATURES ON MONDAY WILL BE HELD DOWN INTO
THE 30S W/CLOUDS AND A NNW WIND OF 10 TO 20 MPH.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A NNW WIND AND CLOUDS LOOK TO HANG ON ESPECIALLY FOR NORTHERN AND
EASTERN AREAS MONDAY NIGHT W/CAA CONTINUING TO POUR INTO THE
REGION. ANOTHER ITEM TO BE AWARE OF WILL BE POTENTIAL FOR STREAMERS
OF LIGHT SNOW FROM THE OPEN ST. LAWRENCE FOR PORTIONS OF NORTHERN
AND EASTERN MAINE. THE MODEL GUIDANCE TENDS TO HAVE A DIFFICULT
TIME IN PICKING UP THIS MESO-SCALE FEATURE. THE HRRR MODEL AND
NAM12 TEND TO CATCH ON AS WE CLOSE IN CLOSER TO THE EVENT.
CONTINUED BREEZY AND COLD ON TUESDAY W/SOME PARTIAL CLEARING
ACROSS NORTHERN MAINE AS HIGH PRES STARTS TO MOVE IN FROM THE W.
DOWNEAST AND THE COAST SHOULD SEE A DECENT AMOUNT OF SUNSHINE.
DAYTIME TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL FOR LATE
NOVEMBER.
STRONG HIGH PRES IS FORECAST TO BUILD ACROSS THE REGION TUESDAY
NIGHT INTO WEDNESDAY AND THEN LIFT TO THE NE INTO THE NW ATLC ON
THANKSGIVING DAY. THIS WILL MEAN DRY TRAVEL WEATHER FOR THE
THANKSGIVING HOLIDAY W/MODERATING TEMPERATURES.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
NEAR TERM: VFR CONDITIONS THROUGH 06Z TONIGHT THEN CIGS LOWERING
TO MVFR RESTRICTIONS AFTER THIS TIME. IFR EXPECTED AT FVE, HUL AND
BHB WITH LOW MVFR EXPECTED AT CAR, PQI AND BGR BUT CANNOT RULE OUT
THESE TERMINALS WILL DROP TO IFR AT SOME POINT TONIGHT. CONFIDENCE
IS LOW SO HAVE NOT INCLUDED IN TAFS.
SHORT TERM: IFR/MVFR CONDITIONS FOR SUNDAY W/IFR MAINLY FROM KHUL
TO KBHB. MVFR FOR THE REMAINDER OF THE TAF SITES THROUGH SUNDAY
EVENING. CONDITIONS EXPECTED TO IMPROVE TO VFR FOR KBGR AND KBHB
FRO MONDAY WHILE THE NORTHERN TAF SITES COULD SEE PERIODS OF MVFR
CIGS. ATTM, VFR EXPECTED FOR ALL TAF SITES FOR TUESDAY INTO
WEDNESDAY
&&
.MARINE...
NEAR TERM: FOR SUSTAINED WINDS HAVE USED THE NAM12. FOR WAVES:
BUOY OBSERVATIONS INDICATE LONG PERIOD INCOMING SWELL STILL
PRESENT FROM SOUTHEASTERLY FETCH EARLY FRIDAY. EXPECT THIS TO
SUBSIDE RAPIDLY EARLY TODAY WITH OFF-SHORE WIND WAVE BECOMING THE
PREDOMINATE WAVE SYSTEM. SEAS WILL SUBSIDE RAPIDLY TONIGHT ALONG
WITH WINDS WITH LONG PERIOD SOUTHEASTERLY WAVE SYSTEM 1-2 FEET/8
SECONDS ONCE AGAIN BECOMING PREDOMINATE.
SHORT TERM: LOOKING FOR THE POTENTIAL FOR SCA CONDITIONS TO
DEVELOP SUNDAY NIGHT INTO MONDAY ESPECIALLY FOR THE OUTER ZONES.
WINDS ARE EXPECTED TO INCREASE TO 15 TO 20 KT W/GUSTS OF 25 KTS
AND A SWELL GENERATION TAKING PLACE ALLOWING FOR SEAS TO BUILD TO
5 TO 7 FT. AS A MATTER OF FACT, SCA CONDITIONS COULD HANG ON RIGHT
INTO MONDAY AS THE PRES GRADIENT TIGHTENS BETWEEN THE LOW PASSING
ACROSS THE MARITIMES AND STRONG HIGH PRES MOVING IN FROM THE W.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...FARRAR/MIGNONE
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...FARRAR/MIGNONE/HEWITT
MARINE...FARRAR/MIGNONE/HEWITT
AREA FORECAST DISCUSSION
NWS CARIBOU ME
920 AM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL CREST OVER THE REGION TODAY. LOW PRESSURE WILL
MOVE NORTHWEST OF THE AREA ON SUNDAY WITH SOME RAIN. A SECOND
AREA OF LOW PRESSURE WILL LIFT ACROSS THE GULF OF MAINE SUNDAY
NIGHT AND THEN INTO THE MARITIMES ON MONDAY WITH MUCH COLDER AIR.
&&
.NEAR TERM /THROUGH TONIGHT/...
920 AM UPDATE...
CRYSTAL CLR SKIES ACRS NRN AND SERN ZONES THIS MRNG WITH HIGH CLDS
STREAMING NORTH INTO CNTRL SXNS AHD OF S/WV MOVING UP ON SW FLOW.
HV GONE WITH MOSUNNY SKIES THIS MRNG FOR NRN SXNS FOR A FEW MORE
HRS BUT EXPECT MID-HIGH CLDS TO WORK IN BY LATE MRNG. ADJUSTED
GRIDS FOR HRLY T/TD VALUES BUT TEMPS SHUD QUICKLY WARM THIS MRNG.
MAY NEED TO BOOST HIGHS A DEGREE OR TWO WITH NEXT UPDATE. NO OTHER
CHGS NEEDED AT THIS TIME AS HIPRES WL BUILD EAST INTO AREA THIS
AFTN.
PREV DISCUSSION BLO...
HIGH PRESSURE WILL BUILD IN FROM THE WEST THIS MORNING WITH
CLEARING EARLY TODAY. THE HIGH PRESSURE SYSTEM WILL CREST OVER THE
REGION TODAY THEN MOVE OFF TO THE EAST THIS EVENING. WEAK LOW
PRESSURE WILL DEVELOP OVER THE GULF OF MAINE BEHIND THE DEPARTING
LOW AND SPREAD RAIN AND SNOW INTO NEW BRUNSWICK TONIGHT. INTENSE
LOW PRESSURE WILL MOVE INTO THE GREAT LAKES TONIGHT THEN MOVE INTO
SOUTHEASTERN QUEBEC PROVINCE EARLY SUNDAY.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
AN INTERESTING SETUP FOR SUNDAY NIGHT INTO EARLY MONDAY.
A FRONTAL SYSTEM IS FORECAST TO SLIDE ACROSS THE AREA ON SUNDAY
W/SOME SHOWERS OR LIGHT RAIN PULLING OUT OF THE AREA IN THE
MORNING. THE 2ND BATCH OF PRECIP IN THE FORM OF RAIN IS EXPECTED
TO SET UP LATER IN DAY AS LOW PRES DEVELOPS OFF THE SOUTHERN NEW
ENGLAND COAST AND LIFTS NNE. THE AREAS THAT WILL SEE MEASURABLE
QPF WILL BE ACROSS THE EASTERN 1/2 OF THE CWA WHERE THE BEST
FORCING AND LLVL CONVERGENCE WILL BE LOCATED. AS THE LOW LIFTS TO
NNE AND THE UPPER TROF DIGS SOME AS IT SWINGS INTO THE NE, COLDER
AIR WILL START TO FILTER INTO THE REGION. THE ECMWF AND GFS ARE IN
AGREEMENT W/THE COLDER AIR COMING IN BY THE EVENING WHILE THE
CANADIAN GEM & NAM HOLD THE COLDER AIR BACK BY 3-6 HRS. DECIDED TO
GO W/A CONSENSUS BLEND OF THE GUIDANCE FOR THIS PACKAGE SHOWING
RAIN GOING OVER TO A PERIOD OF SNOW BY 11 PM OR SO. ALL THE
GUIDANCE IS IN AGREEMENT THAT THE BULK OF THE QPF WILL BE ACROSS
THE EASTERN 3RD OF THE CWA SAY FROM FROM HOULTON DOWN INTO HANCOCK
AND WASHINGTON COUNTY W/UP AROUND 0.50 INCHES. ATTM, IF THERE IS
TO BE ANY SNOWFALL ACCUMULATION, IT WILL BE ACROSS EASTERN
WASHINGTON COUNTY W/A SLUSHY INCH POSSIBLE BEFORE THINGS WIND DOWN
MONDAY MORNING. TEMPERATURES ARE FORECAST TO DROP DOWN INTO THE
LOWER 30S ACROSS EASTERN AREAS AFTER MIDNIGHT W/MID AND UPPER 20S
BACK ACROSS THE W AND NW AREAS.
THE LOW IS FORECAST TO QUICKLY LIFT ACROSS THE MARITIMES ON MONDAY
W/CAA POURING INTO THE REGION AND DRIER CONDITIONS. THERE IS SOME
CONCERN THE CLOUDS ACROSS NORTHERN AND EASTERN MAINE MIGHT HANG ON
THROUGH MONDAY W/A NNW FLOW COMING IN OFF THE OPEN ST. LAWRENCE.
THE GFS SOUNDINGS HINT AT THIS TO BE POSSIBLE W/SOME MOISTURE
SHOWING UP BELOW 3000 FT. THIS SETUP SIMILAR TO THIS SCENARIO TOOK
PLACE LAST WEEK WHEN A CLOUD DECK BELOW 2500 FT HUNG ON LONGER
THAN ANTICIPATED. TEMPERATURES ON MONDAY WILL BE HELD DOWN INTO
THE 30S W/CLOUDS AND A NNW WIND OF 10 TO 20 MPH.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A NNW WIND AND CLOUDS LOOK TO HANG ON ESPECIALLY FOR NORTHERN AND
EASTERN AREAS MONDAY NIGHT W/CAA CONTINUING TO POUR INTO THE
REGION. ANOTHER ITEM TO BE AWARE OF WILL BE POTENTIAL FOR STREAMERS
OF LIGHT SNOW FROM THE OPEN ST. LAWRENCE FOR PORTIONS OF NORTHERN
AND EASTERN MAINE. THE MODEL GUIDANCE TENDS TO HAVE A DIFFICULT
TIME IN PICKING UP THIS MESO-SCALE FEATURE. THE HRRR MODEL AND
NAM12 TEND TO CATCH ON AS WE CLOSE IN CLOSER TO THE EVENT.
CONTINUED BREEZY AND COLD ON TUESDAY W/SOME PARTIAL CLEARING
ACROSS NORTHERN MAINE AS HIGH PRES STARTS TO MOVE IN FROM THE W.
DOWNEAST AND THE COAST SHOULD SEE A DECENT AMOUNT OF SUNSHINE.
DAYTIME TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL FOR LATE
NOVEMBER.
STRONG HIGH PRES IS FORECAST TO BUILD ACROSS THE REGION TUESDAY
NIGHT INTO WEDNESDAY AND THEN LIFT TO THE NE INTO THE NW ATLC ON
THANKSGIVING DAY. THIS WILL MEAN DRY TRAVEL WEATHER FOR THE
THANKSGIVING HOLIDAY W/MODERATING TEMPERATURES.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: EXPECT VFR CONDITIONS TODAY AND TONIGHT.
SHORT TERM: IFR/MVFR CONDITIONS FOR SUNDAY W/IFR MAINLY FROM KHUL
TO KBHB. MVFR FOR THE REMAINDER OF THE TAF SITES THROUGH SUNDAY
EVENING. CONDITIONS EXPECTED TO IMPROVE TO VFR FOR KBGR AND KBHB
FRO MONDAY WHILE THE NORTHERN TAF SITES COULD SEE PERIODS OF MVFR
CIGS. ATTM, VFR EXPECTED FOR ALL TAF SITES FOR TUESDAY INTO
WEDNESDAY
&&
.MARINE...
UPDATE 0615 AM: HAVE REMOVE SCA FOR ZONES 51 & 52 AND WILL KEEP
SCA FOR ZONE 50 UNTIL 15Z.
NEAR TERM: FOR SUSTAINED WINDS HAVE USED THE NAM12. FOR WAVES:
BUOY OBSERVATIONS INDICATE LONG PERIOD INCOMING SWELL STILL
PRESENT FROM SOUTHEASTERLY FETCH EARLY FRIDAY. EXPECT THIS TO
SUBSIDE RAPIDLY EARLY TODAY WITH OFF-SHORE WIND WAVE BECOMING THE
PREDOMINATE WAVE SYSTEM. SEAS WILL SUBSIDE RAPIDLY TONIGHT ALONG
WITH WINDS WITH LONG PERIOD SOUTHEASTERLY WAVE SYSTEM 1-2 FEET/8
SECONDS ONCE AGAIN BECOMING PREDOMINATE.
SHORT TERM: LOOKING FOR THE POTENTIAL FOR SCA CONDITIONS TO
DEVELOP SUNDAY NIGHT INTO MONDAY ESPECIALLY FOR THE OUTER ZONES.
WINDS ARE EXPECTED TO INCREASE TO 15 TO 20 KT W/GUSTS OF 25 KTS
AND A SWELL GENERATION TAKING PLACE ALLOWING FOR SEAS TO BUILD TO
5 TO 7 FT. AS A MATTER OF FACT, SCA CONDITIONS COULD HANG ON RIGHT
INTO MONDAY AS THE PRES GRADIENT TIGHTENS BETWEEN THE LOW PASSING
ACROSS THE MARITIMES AND STRONG HIGH PRES MOVING IN FROM THE W.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR ANZ050.
&&
$$
NEAR TERM...FARRAR/MIGNONE
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...FARRAR/MIGNONE/HEWITT
MARINE...FARRAR/MIGNONE/HEWITT
AREA FORECAST DISCUSSION
NWS CARIBOU ME
623 AM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL CREST OVER THE REGION TODAY. LOW PRESSURE WILL
MOVE NORTHWEST OF THE AREA ON SUNDAY WITH SOME RAIN. A SECOND
AREA OF LOW PRESSURE WILL LIFT ACROSS THE GULF OF MAINE SUNDAY
NIGHT AND THEN INTO THE MARITIMES ON MONDAY WITH MUCH COLDER AIR.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE 6:15 AM: HAVE ADJUSTED TEMPERATURE AND DEW POINT BASED ON
LATEST OBSERVATIONS. NO OTHER CHANGES.
HIGH PRESSURE WILL BUILD IN FROM THE WEST THIS MORNING WITH
CLEARING EARLY TODAY. THE HIGH PRESSURE SYSTEM WILL CREST OVER THE
REGION TODAY THEN MOVE OFF TO THE EAST THIS EVENING. WEAK LOW
PRESSURE WILL DEVELOP OVER THE GULF OF MAINE BEHIND THE DEPARTING
LOW AND SPREAD RAIN AND SNOW INTO NEW BRUNSWICK TONIGHT. INTENSE
LOW PRESSURE WILL MOVE INTO THE GREAT LAKES TONIGHT THEN MOVE INTO
SOUTHEASTERN QUEBEC PROVINCE EARLY SUNDAY.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
AN INTERESTING SETUP FOR SUNDAY NIGHT INTO EARLY MONDAY.
A FRONTAL SYSTEM IS FORECAST TO SLIDE ACROSS THE AREA ON SUNDAY
W/SOME SHOWERS OR LIGHT RAIN PULLING OUT OF THE AREA IN THE
MORNING. THE 2ND BATCH OF PRECIP IN THE FORM OF RAIN IS EXPECTED
TO SET UP LATER IN DAY AS LOW PRES DEVELOPS OFF THE SOUTHERN NEW
ENGLAND COAST AND LIFTS NNE. THE AREAS THAT WILL SEE MEASURABLE
QPF WILL BE ACROSS THE EASTERN 1/2 OF THE CWA WHERE THE BEST
FORCING AND LLVL CONVERGENCE WILL BE LOCATED. AS THE LOW LIFTS TO
NNE AND THE UPPER TROF DIGS SOME AS IT SWINGS INTO THE NE, COLDER
AIR WILL START TO FILTER INTO THE REGION. THE ECMWF AND GFS ARE IN
AGREEMENT W/THE COLDER AIR COMING IN BY THE EVENING WHILE THE
CANADIAN GEM & NAM HOLD THE COLDER AIR BACK BY 3-6 HRS. DECIDED TO
GO W/A CONSENSUS BLEND OF THE GUIDANCE FOR THIS PACKAGE SHOWING
RAIN GOING OVER TO A PERIOD OF SNOW BY 11 PM OR SO. ALL THE
GUIDANCE IS IN AGREEMENT THAT THE BULK OF THE QPF WILL BE ACROSS
THE EASTERN 3RD OF THE CWA SAY FROM FROM HOULTON DOWN INTO HANCOCK
AND WASHINGTON COUNTY W/UP AROUND 0.50 INCHES. ATTM, IF THERE IS
TO BE ANY SNOWFALL ACCUMULATION, IT WILL BE ACROSS EASTERN
WASHINGTON COUNTY W/A SLUSHY INCH POSSIBLE BEFORE THINGS WIND DOWN
MONDAY MORNING. TEMPERATURES ARE FORECAST TO DROP DOWN INTO THE
LOWER 30S ACROSS EASTERN AREAS AFTER MIDNIGHT W/MID AND UPPER 20S
BACK ACROSS THE W AND NW AREAS.
THE LOW IS FORECAST TO QUICKLY LIFT ACROSS THE MARITIMES ON MONDAY
W/CAA POURING INTO THE REGION AND DRIER CONDITIONS. THERE IS SOME
CONCERN THE CLOUDS ACROSS NORTHERN AND EASTERN MAINE MIGHT HANG ON
THROUGH MONDAY W/A NNW FLOW COMING IN OFF THE OPEN ST. LAWRENCE.
THE GFS SOUNDINGS HINT AT THIS TO BE POSSIBLE W/SOME MOISTURE
SHOWING UP BELOW 3000 FT. THIS SETUP SIMILAR TO THIS SCENARIO TOOK
PLACE LAST WEEK WHEN A CLOUD DECK BELOW 2500 FT HUNG ON LONGER
THAN ANTICIPATED. TEMPERATURES ON MONDAY WILL BE HELD DOWN INTO
THE 30S W/CLOUDS AND A NNW WIND OF 10 TO 20 MPH.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A NNW WIND AND CLOUDS LOOK TO HANG ON ESPECIALLY FOR NORTHERN AND
EASTERN AREAS MONDAY NIGHT W/CAA CONTINUING TO POUR INTO THE
REGION. ANOTHER ITEM TO BE AWARE OF WILL BE POTENTIAL FOR STREAMERS
OF LIGHT SNOW FROM THE OPEN ST. LAWRENCE FOR PORTIONS OF NORTHERN
AND EASTERN MAINE. THE MODEL GUIDANCE TENDS TO HAVE A DIFFICULT
TIME IN PICKING UP THIS MESO-SCALE FEATURE. THE HRRR MODEL AND
NAM12 TEND TO CATCH ON AS WE CLOSE IN CLOSER TO THE EVENT.
CONTINUED BREEZY AND COLD ON TUESDAY W/SOME PARTIAL CLEARING
ACROSS NORTHERN MAINE AS HIGH PRES STARTS TO MOVE IN FROM THE W.
DOWNEAST AND THE COAST SHOULD SEE A DECENT AMOUNT OF SUNSHINE.
DAYTIME TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL FOR LATE
NOVEMBER.
STRONG HIGH PRES IS FORECAST TO BUILD ACROSS THE REGION TUESDAY
NIGHT INTO WEDNESDAY AND THEN LIFT TO THE NE INTO THE NW ATLC ON
THANKSGIVING DAY. THIS WILL MEAN DRY TRAVEL WEATHER FOR THE
THANKSGIVING HOLIDAY W/MODERATING TEMPERATURES.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: EXPECT VFR CONDITIONS TODAY AND TONIGHT.
SHORT TERM: IFR/MVFR CONDITIONS FOR SUNDAY W/IFR MAINLY FROM KHUL
TO KBHB. MVFR FOR THE REMAINDER OF THE TAF SITES THROUGH SUNDAY
EVENING. CONDITIONS EXPECTED TO IMPROVE TO VFR FOR KBGR AND KBHB
FRO MONDAY WHILE THE NORTHERN TAF SITES COULD SEE PERIODS OF MVFR
CIGS. ATTM, VFR EXPECTED FOR ALL TAF SITES FOR TUESDAY INTO
WEDNESDAY
&&
.MARINE...
UPDATE 0615 AM: HAVE REMOVE SCA FOR ZONES 51 & 52 AND WILL KEEP
SCA FOR ZONE 50 UNTIL 15Z.
NEAR TERM: FOR SUSTAINED WINDS HAVE USED THE NAM12. FOR WAVES:
BUOY OBSERVATIONS INDICATE LONG PERIOD INCOMING SWELL STILL
PRESENT FROM SOUTHEASTERLY FETCH EARLY FRIDAY. EXPECT THIS TO
SUBSIDE RAPIDLY EARLY TODAY WITH OFF-SHORE WIND WAVE BECOMING THE
PREDOMINATE WAVE SYSTEM. SEAS WILL SUBSIDE RAPIDLY TONIGHT ALONG
WITH WINDS WITH LONG PERIOD SOUTHEASTERLY WAVE SYSTEM 1-2 FEET/8
SECONDS ONCE AGAIN BECOMING PREDOMINATE.
SHORT TERM: LOOKING FOR THE POTENTIAL FOR SCA CONDITIONS TO
DEVELOP SUNDAY NIGHT INTO MONDAY ESPECIALLY FOR THE OUTER ZONES.
WINDS ARE EXPECTED TO INCREASE TO 15 TO 20 KT W/GUSTS OF 25 KTS
AND A SWELL GENERATION TAKING PLACE ALLOWING FOR SEAS TO BUILD TO
5 TO 7 FT. AS A MATTER OF FACT, SCA CONDITIONS COULD HANG ON RIGHT
INTO MONDAY AS THE PRES GRADIENT TIGHTENS BETWEEN THE LOW PASSING
ACROSS THE MARITIMES AND STRONG HIGH PRES MOVING IN FROM THE W.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR ANZ050.
&&
$$
NEAR TERM...MIGNONE
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...MIGNONE/HEWITT
MARINE...MIGNONE/HEWITT
AREA FORECAST DISCUSSION
NWS CARIBOU ME
458 AM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL CREST OVER THE REGION TODAY. LOW PRESSURE WILL
MOVE NORTHWEST OF THE AREA ON SUNDAY WITH SOME RAIN. A SECOND
AREA OF LOW PRESSURE WILL LIFT ACROSS THE GULF OF MAINE SUNDAY
NIGHT AND THEN INTO THE MARITIMES ON MONDAY WITH MUCH COLDER AIR.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE WILL BUILD IN FROM THE WEST THIS MORNING WITH
CLEARING EARLY TODAY. THE HIGH PRESSURE SYSTEM WILL CREST OVER THE
REGION TODAY THEN MOVE OFF TO THE EAST THIS EVENING. WEAK LOW
PRESSURE WILL DEVELOP OVER THE GULF OF MAINE BEHIND THE DEPARTING
LOW AND SPREAD RAIN AND SNOW INTO NEW BRUNSWICK TONIGHT. INTENSE
LOW PRESSURE WILL MOVE INTO THE GREAT LAKES TONIGHT THEN MOVE INTO
SOUTHEASTERN QUEBEC PROVINCE EARLY SUNDAY.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
AN INTERESTING SETUP FOR SUNDAY NIGHT INTO EARLY MONDAY.
A FRONTAL SYSTEM IS FORECAST TO SLIDE ACROSS THE AREA ON SUNDAY
W/SOME SHOWERS OR LIGHT RAIN PULLING OUT OF THE AREA IN THE
MORNING. THE 2ND BATCH OF PRECIP IN THE FORM OF RAIN IS EXPECTED
TO SET UP LATER IN DAY AS LOW PRES DEVELOPS OFF THE SOUTHERN NEW
ENGLAND COAST AND LIFTS NNE. THE AREAS THAT WILL SEE MEASURABLE
QPF WILL BE ACROSS THE EASTERN 1/2 OF THE CWA WHERE THE BEST
FORCING AND LLVL CONVERGENCE WILL BE LOCATED. AS THE LOW LIFTS TO
NNE AND THE UPPER TROF DIGS SOME AS IT SWINGS INTO THE NE, COLDER
AIR WILL START TO FILTER INTO THE REGION. THE ECMWF AND GFS ARE IN
AGREEMENT W/THE COLDER AIR COMING IN BY THE EVENING WHILE THE
CANADIAN GEM & NAM HOLD THE COLDER AIR BACK BY 3-6 HRS. DECIDED TO
GO W/A CONSENSUS BLEND OF THE GUIDANCE FOR THIS PACKAGE SHOWING
RAIN GOING OVER TO A PERIOD OF SNOW BY 11 PM OR SO. ALL THE
GUIDANCE IS IN AGREEMENT THAT THE BULK OF THE QPF WILL BE ACROSS
THE EASTERN 3RD OF THE CWA SAY FROM FROM HOULTON DOWN INTO HANCOCK
AND WASHINGTON COUNTY W/UP AROUND 0.50 INCHES. ATTM, IF THERE IS
TO BE ANY SNOWFALL ACCUMULATION, IT WILL BE ACROSS EASTERN
WASHINGTON COUNTY W/A SLUSHY INCH POSSIBLE BEFORE THINGS WIND DOWN
MONDAY MORNING. TEMPERATURES ARE FORECAST TO DROP DOWN INTO THE
LOWER 30S ACROSS EASTERN AREAS AFTER MIDNIGHT W/MID AND UPPER 20S
BACK ACROSS THE W AND NW AREAS.
THE LOW IS FORECAST TO QUICKLY LIFT ACROSS THE MARITIMES ON MONDAY
W/CAA POURING INTO THE REGION AND DRIER CONDITIONS. THERE IS SOME
CONCERN THE CLOUDS ACROSS NORTHERN AND EASTERN MAINE MIGHT HANG ON
THROUGH MONDAY W/A NNW FLOW COMING IN OFF THE OPEN ST. LAWRENCE.
THE GFS SOUNDINGS HINT AT THIS TO BE POSSIBLE W/SOME MOISTURE
SHOWING UP BELOW 3000 FT. THIS SETUP SIMILAR TO THIS SCENARIO TOOK
PLACE LAST WEEK WHEN A CLOUD DECK BELOW 2500 FT HUNG ON LONGER
THAN ANTICIPATED. TEMPERATURES ON MONDAY WILL BE HELD DOWN INTO
THE 30S W/CLOUDS AND A NNW WIND OF 10 TO 20 MPH.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A NNW WIND AND CLOUDS LOOK TO HANG ON ESPECIALLY FOR NORTHERN AND
EASTERN AREAS MONDAY NIGHT W/CAA CONTINUING TO POUR INTO THE
REGION. ANOTHER ITEM TO BE AWARE OF WILL BE POTENTIAL FOR STREAMERS
OF LIGHT SNOW FROM THE OPEN ST. LAWRENCE FOR PORTIONS OF NORTHERN
AND EASTERN MAINE. THE MODEL GUIDANCE TENDS TO HAVE A DIFFICULT
TIME IN PICKING UP THIS MESO-SCALE FEATURE. THE HRRR MODEL AND
NAM12 TEND TO CATCH ON AS WE CLOSE IN CLOSER TO THE EVENT.
CONTINUED BREEZY AND COLD ON TUESDAY W/SOME PARTIAL CLEARING
ACROSS NORTHERN MAINE AS HIGH PRES STARTS TO MOVE IN FROM THE W.
DOWNEAST AND THE COAST SHOULD SEE A DECENT AMOUNT OF SUNSHINE.
DAYTIME TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL FOR LATE
NOVEMBER.
STRONG HIGH PRES IS FORECAST TO BUILD ACROSS THE REGION TUESDAY
NIGHT INTO WEDNESDAY AND THEN LIFT TO THE NE INTO THE NW ATLC ON
THANKSGIVING DAY. THIS WILL MEAN DRY TRAVEL WEATHER FOR THE
THANKSGIVING HOLIDAY W/MODERATING TEMPERATURES.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: EXPECT VFR CONDITIONS TODAY AND TONIGHT.
SHORT TERM: IFR/MVFR CONDITIONS FOR SUNDAY W/IFR MAINLY FROM KHUL
TO KBHB. MVFR FOR THE REMAINDER OF THE TAF SITES THROUGH SUNDAY
EVENING. CONDITIONS EXPECTED TO IMPROVE TO VFR FOR KBGR AND KBHB
FRO MONDAY WHILE THE NORTHERN TAF SITES COULD SEE PERIODS OF MVFR
CIGS. ATTM, VFR EXPECTED FOR ALL TAF SITES FOR TUESDAY INTO
WEDNESDAY
&&
.MARINE...
NEAR TERM: FOR SUSTAINED WINDS HAVE USED THE NAM12. FOR WAVES:
BUOY OBSERVATIONS INDICATE LONG PERIOD INCOMING SWELL STILL
PRESENT FROM SOUTHEASTERLY FETCH EARLY FRIDAY. EXPECT THIS TO
SUBSIDE RAPIDLY EARLY TODAY WITH OFF-SHORE WIND WAVE BECOMING THE
PREDOMINATE WAVE SYSTEM. SEAS WILL SUBSIDE RAPIDLY TONIGHT ALONG
WITH WINDS WITH LONG PERIOD SOUTHEASTERLY WAVE SYSTEM 1-2 FEET/8
SECONDS ONCE AGAIN BECOMING PREDOMINATE.
SHORT TERM: LOOKING FOR THE POTENTIAL FOR SCA CONDITIONS TO
DEVELOP SUNDAY NIGHT INTO MONDAY ESPECIALLY FOR THE OUTER ZONES.
WINDS ARE EXPECTED TO INCREASE TO 15 TO 20 KT W/GUSTS OF 25 KTS
AND A SWELL GENERATION TAKING PLACE ALLOWING FOR SEAS TO BUILD TO
5 TO 7 FT. AS A MATTER OF FACT, SCA CONDITIONS COULD HANG ON RIGHT
INTO MONDAY AS THE PRES GRADIENT TIGHTENS BETWEEN THE LOW PASSING
ACROSS THE MARITIMES AND STRONG HIGH PRES MOVING IN FROM THE W.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR
ANZ050>052.
&&
$$
NEAR TERM...MIGNONE
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...MIGNONE/HEWITT
MARINE...MIGNONE/HEWITT
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
1102 AM EST SAT NOV 21 2015
.SYNOPSIS...
A COLD FRONT WILL SPAWN RAIN AND SNOW SHOWERS TONIGHT. SNOW
SHOWERS ON SUNDAY WILL AFFECT AREAS NORTH OF INTERSTATE 80.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRIMARY ADJUSTMENTS THIS MORNING INCLUDE INCREASE IN SKY COVER TO
REFLECT CURRENT MID-LEVEL DECK AND MODEST CHANGES TO MAXIMA GIVEN
PERSISTENT CLOUD DECK. SELY WIND IS EXPECTED TO INCREASE DURING
THE NEXT HOUR OR TWO...WHICH WILL PROVIDE A DOWNSLOPE COMPONENT
AND MAY AID IN INCREASING TEMPS SLIGHTLY VIA COMPRESSIONAL
WARMING. PREVIOUS DISCUSSION FOLLOWS...
THE PREDAWN UPDATE INCLUDED AN UPWARD BUMP IN TEMPS AND WIND GUSTS
BASED ON THE LATEST RAP AND HRR MDL SOUNDINGS WHICH INDICATE LESS
CLOUD COVER AND A HIGHER MIXING HEIGHT IN THE WARM ADVECTION
REGIME OF TODAY.
PRECIP CHANCES WILL BE ON THE INCREASE LATE THIS EVE...CUMULATING
IN LIKELY AND CATEGORICAL NUMBERS FOR THE REGION...AS A COLD FRONT
SWEEPS OUT OF THE MIDWEST WITH LOW PRESSURE DEEPENING OVR THE
GREAT LAKES.
WITH THE SFC LOW PROJECTED TO REMAIN WEST OF THE IMMEDIATE AREA...AND
WITH DRY ENCROACHMENT AND MID LEVEL TROUGH PROGRESSION...THE
PRECIP POTENTIAL IS EXPECTED TO REMAIN WITH THE ACTUAL FRONT. THE
TEMPERATURE GRADIENT IS STILL EXPECTED TO SUPPORT A CHANGE FROM
RAIN...TO SNOW SHOWERS AFTER FRONTAL PASSAGE...ALTHOUGH THE FADING
DYNAMICS PER THE WESTWARD TRACK AND RELATIVELY WARM BOUNDARY LAYER
WILL NOT BE SUPPORTIVE OF ANY SIGNIFICANT ACCUMULATION OUTSIDE OF
THE I 80 CORRIDOR AND RIDGES WHICH COULD SEE AN INCH IN THE
PREDAWN.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
ZONES NORTH OF I 80 AS WELL AS THE RIDGES WILL EXPERIENCE SOME
LINGERING SNOW SHOWER POTENTIAL INTO SUNDAY. THE BETTER
ACCUMULATION POTENTIAL...ALBEIT ON THE ORDER OF AN ANOTHER INCH
GIVEN PROJECTIONS OF A FAIRLY DEEP MIXING LAYER WITH THE LAKE
TAP...IS LIKELY TO BE CONFINED TO EXTREME NORTHERN PORTIONS OF
MERCER AND VENANGO COUNTIES GIVEN THE STRONG WESTERLY WIND
COMPONENT OF THE BOUNDARY LAYER FLOW. OTHERWISE...SUNDAY LOOKS TO
BE DRY/MAYBE SOME FLURRIES...BUT COLD WITH HIGHS FORECAST
APPROXIMATELY 10 DEGREES UNDER THE AVERAGES...WHICH WERE FORECAST
USING A GUIDANCE BLEND.
THE COLD UPPER TROUGH IS PROJECTED TO PIVOT EASTWARD WHILE A
SURFACE HIGH BUILDS OVER THE REGION ON MONDAY. A WEAK SHORTWAVE
EMBEDDED IN THE FLOW MAY PROVIDE FOR ADDITIONAL CLOUD COVER...BUT
TEMPERATURES SHOULD BEGIN TO SLOWLY MODERATE FOR THE START OF THE
WORK-WEEK.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
COLD EARLY WEEK WEATHER WITH THE AFOREMENTIONED PROGRESSIVE UPR TROUGH
IS FORECAST TO MODERATE TOWARD SEASONAL READINGS BY MIDWEEK AS HEIGHTS
RISE/FLATTEN IN ADVANCE OF ANOTHER WRN CONUS LOW. A GUIDANCE BLEND
WAS USED FOR THE LONG TERM FORECAST.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS STILL EXPECTED THROUGH THIS EVENING. LIGHT
PRECIPITATION IS EXPECTED OVERNIGHT AT MOST TERMINALS AS A
FRONTAL BOUNDARY CROSSES THE REGION...BUT UPPER-LEVEL SUPPORT WILL
WANE QUICKLY...SUGGESTING A BRIEF WINDOW FOR PRECIPITATION BEFORE
THE SYSTEM DRY SLOT BRINGS AN END TO ANY PRECIPITATION.
COLD AIR WILL INVADE LATE TONIGHT...WHICH MAY PROVIDE A VERY BRIEF
CHANGE TO LIGHT SNOW AT THE BACK EDGE OF PRECIPITATION. AS COLD
AIR DEPTH INCREASES...LAPSE RATES WILL STEEPEN CONSIDERABLY AND
WILL SUPPORT LAKE-ENHANCED PRECIPITATION...PRIMARILY AT NORTHERN
TERMINALS GIVEN WIND DIRECTION PRIMARILY FROM THE WEST. CONDITIONS
DURING THIS TIME LIKELY WILL SUPPORT IFR-MVFR FLIGHT CATEGORIES
OR LOWER...ESPECIALLY IN ANY SNOW SHOWERS.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY/...
RESTRICTIONS ARE EXPECTED TO CONTINUE THRU SUNDAY NIGHT WITH AN
EASTERN CONUS UPPER TROUGH AND COLD WNWLY FLOW.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
UPDATE...KRAMAR
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
527 AM EST SAT NOV 21 2015
.SYNOPSIS...
A REINFORCING COLD FRONT WILL SPAWN RAIN AND SNOW SHOWERS TONIGHT.
SNOW SHOWERS WILL PLAGUE AREAS NORTH OF I 80 ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE PREDAWN UPDATE INCLUDED AN UPWARD BUMP IN TEMPS AND WIND GUSTS
BASED ON THE LATEST RAP AND HRR MDL SOUNDINGS WHICH INDICATE LESS
CLOUD COVER AND A HIGHER MIXING HEIGHT IN THE WARM ADVECTION
REGIME OF TODAY.
PRECIP CHANCES WILL BE ON THE INCREASE LATE THIS EVE...CUMULATING
IN LIKELY AND CATEGORICAL NUMBERS FOR THE REGION...AS A COLD FRONT
SWEEPS OUT OF THE MIDWEST WITH LOW PRESSURE DEEPENING OVR THE
GREAT LAKES.
WITH THE SFC LOW PROJECTED TO REMAIN WEST OF THE IMMEDIATE AREA...AND
WITH DRY ENCROACHMENT AND MID LEVEL TROUGH PROGRESSION...THE
PRECIP POTENTIAL IS EXPECTED TO REMAIN WITH THE ACTUAL FRONT. THE
TEMPERATURE GRADIENT IS STILL EXPECTED TO SUPPORT A CHANGE FROM
RAIN...TO SNOW SHOWERS AFTER FRONTAL PASSAGE...ALTHOUGH THE FADING
DYNAMICS PER THE WESTWARD TRACK AND RELATIVELY WARM BOUNDARY LAYER
WILL NOT BE SUPPORTIVE OF ANY SIGNIFICANT ACCUMULATION OUTSIDE OF
THE I 80 CORRIDOR AND RIDGES WHICH COULD SEE AN INCH IN THE
PREDAWN.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
ZONES NORTH OF I 80 AS WELL AS THE RIDGES WILL EXPERIENCE SOME
LINGERING SNOW SHOWER POTENTIAL INTO SUNDAY. THE BETTER
ACCUMULATION POTENTIAL...ALBEIT ON THE ORDER OF AN ANOTHER INCH
GIVEN PROJECTIONS OF A FAIRLY DEEP MIXING LAYER WITH THE LAKE
TAP...IS LIKELY TO BE CONFINED TO EXTREME NORTHERN PORTIONS OF
MERCER AND VENANGO COUNTIES GIVEN THE STRONG WESTERLY WIND
COMPONENT OF THE BOUNDARY LAYER FLOW. OTHERWISE...SUNDAY LOOKS TO
BE DRY/MAYBE SOME FLURRIES...BUT COLD WITH HIGHS FORECAST
APPROXIMATELY 10 DEGREES UNDER THE AVERAGES...WHICH WERE FORECAST
USING A GUIDANCE BLEND.
THE COLD UPPER TROUGH IS PROJECTED TO PIVOT EASTWARD WHILE A
SURFACE HIGH BUILDS OVER THE REGION ON MONDAY. A WEAK SHORTWAVE
EMBEDDED IN THE FLOW MAY PROVIDE FOR ADDITIONAL CLOUD COVER...BUT
TEMPERATURES SHOULD BEGIN TO SLOWLY MODERATE FOR THE START OF THE
WORK-WEEK.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
COLD EARLY WEEK WEATHER WITH THE AFOREMENTIONED PROGRESSIVE UPR TROUGH
IS FORECAST TO MODERATE TOWARD SEASONAL READINGS BY MIDWEEK AS HEIGHTS
RISE/FLATTEN IN ADVANCE OF ANOTHER WRN CONUS LOW. A GUIDANCE BLEND
WAS USED FOR THE LONG TERM FORECAST.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH MOST OF TODAY. A COLD FRONT
IS PROGGED FOR A LATE AFTERNOON/EVENING PASSAGE WITH A FEW SHOWERS
AND CONDITIONS DETERIORATION TO MVFR NEAR AND BEHIND THE
FRONT....WITH A PERIOD OF GUSTY W WINDS.
OUTLOOK...SATURDAY NIGHT THROUGH WEDNESDAY/...
RESTRICTIONS ARE EXPECTED TO CONTINUE THRU SUNDAY NIGHT WITH AN
EASTERN CONUS UPPER TROUGH AND COLD W-NW FLOW.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
15/22
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1154 AM CST SAT NOV 21 2015
.SHORT TERM: (Through Tonight)
Issued at 255 AM CST Sat Nov 21 2015
Ongoing precipitation will continue through early afternoon,
eventually tapering off from west to east due to strong
subsidence behind a cold front. A few snowflakes could mix in
with the rain at times almost anywhere across the CWA, especially
just as the rain is ending because that is when the colder air
will also be arriving. However, only the far northern CWA appears
to stay cold enough for long enough to see any accumulation, and
likely only a dusting at best.
Strong CAA behind the aforementioned cold front will produce
falling temperatures during the day across most of the area. The
exception may be across the far eastern CWA where temperatures
could remain steady or perhaps rise by a degree or two before the
front arrives.
Very windy conditions are expected today, especially for the
first few hours after fropa. A tight pressure gradient will lead
to sustained winds of 15-25 mph, and stronger winds aloft will mix
down and produce gusts of 30-40 mph. These values are consistent
with upstream METARs early this morning. BUFKIT soundings from
the RAP and the NAM do suggest that the wind gusts could even be
a bit higher than currently forecast, which would approach
criteria for a wind advisory. However, it does not appear that
wind gusts of that magnitude will be widespread enough to warrant
issuing a wind advisory, therefore no wind headlines are planned
attm. The next shift may revisit the need for wind headlines based
on observational trends. Winds should diminish quickly this
evening.
The coldest temperatures of the season so far are expected
tonight and early tomorrow morning. Overnight lows will likely
drop into the upper teens to lower 20s across the area. Overnight
temperatures would be even lower if it weren`t for the expected
mid/high clouds ahead of a secondary vort max dropping through the
upper trough tonight. These clouds will interfere with radiational
cooling processes.
Kanofsky
.LONG TERM: (Sunday through Friday)
Issued at 255 AM CST Sat Nov 21 2015
A surface high pressure center will be located south of the area
this weekend, keeping winds from the west or west-southwest until
the surface ridge moves farther eastward during the early or
middle part of the week. At that point, winds will likely become
southerly ahead of a developing low pressure system, bringing
warmer air back into the region. Unlike the 00z runs on the last
two days, the current ECMWF/GFS/GEM 00z model runs are in
remarkably good agreement on large scale atmospheric features
through 00z Wed. The primary features of interest are a large,
complex low pressure system over NV/UT and broad southwesterly
flow aloft over MO/IL. Model solutions quickly diverge thereafter,
and confidence in the forecast beyond Tuesday is low.
Kanofsky
&&
.AVIATION: (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1150 AM CST Sat Nov 21 2015
Rapidly moving low pressure system has moved to Indiana taking the
precipitaton with it. Clouds will quickly scatter and clear this
afternoon. Northwest wind will also calm down going light and
variable tonight. High pressure moves east of the area Sunday
bringig a light south wind.
Specifics for KSTL: MVFR clouds looks to scatter and clear around
22z. Clear overnight with wind becoming light and variable after
06z as high pressure moves in. The high quickly moves east Sunday
bringing a light south to southwest wind. An upper level
distubance will bring in some mid clouds overnight.
JPK
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
603 AM CST SAT NOV 21 2015
.SHORT TERM: (Through Tonight)
Issued at 255 AM CST Sat Nov 21 2015
Ongoing precipitation will continue through early afternoon,
eventually tapering off from west to east due to strong
subsidence behind a cold front. A few snowflakes could mix in
with the rain at times almost anywhere across the CWA, especially
just as the rain is ending because that is when the colder air
will also be arriving. However, only the far northern CWA appears
to stay cold enough for long enough to see any accumulation, and
likely only a dusting at best.
Strong CAA behind the aforementioned cold front will produce
falling temperatures during the day across most of the area. The
exception may be across the far eastern CWA where temperatures
could remain steady or perhaps rise by a degree or two before the
front arrives.
Very windy conditions are expected today, especially for the
first few hours after fropa. A tight pressure gradient will lead
to sustained winds of 15-25 mph, and stronger winds aloft will mix
down and produce gusts of 30-40 mph. These values are consistent
with upstream METARs early this morning. BUFKIT soundings from
the RAP and the NAM do suggest that the wind gusts could even be
a bit higher than currently forecast, which would approach
criteria for a wind advisory. However, it does not appear that
wind gusts of that magnitude will be widespread enough to warrant
issuing a wind advisory, therefore no wind headlines are planned
attm. The next shift may revisit the need for wind headlines based
on observational trends. Winds should diminish quickly this
evening.
The coldest temperatures of the season so far are expected
tonight and early tomorrow morning. Overnight lows will likely
drop into the upper teens to lower 20s across the area. Overnight
temperatures would be even lower if it weren`t for the expected
mid/high clouds ahead of a secondary vort max dropping through the
upper trough tonight. These clouds will interfere with radiational
cooling processes.
Kanofsky
.LONG TERM: (Sunday through Friday)
Issued at 255 AM CST Sat Nov 21 2015
A surface high pressure center will be located south of the area
this weekend, keeping winds from the west or west-southwest until
the surface ridge moves farther eastward during the early or
middle part of the week. At that point, winds will likely become
southerly ahead of a developing low pressure system, bringing
warmer air back into the region. Unlike the 00z runs on the last
two days, the current ECMWF/GFS/GEM 00z model runs are in
remarkably good agreement on large scale atmospheric features
through 00z Wed. The primary features of interest are a large,
complex low pressure system over NV/UT and broad southwesterly
flow aloft over MO/IL. Model solutions quickly diverge thereafter,
and confidence in the forecast beyond Tuesday is low.
Kanofsky
&&
.AVIATION: (For the 12z TAFs through 12z Sunday Morning)
Issued at 544 AM CST Sat Nov 21 2015
Surface low nearly on top of STL area attm, with strong pressure
gradient in the wake of the low center really beginning to ramp
up the winds over western sections of the CWA. Rain continues to
work east-northeast in a broad swath from sw MO into s IL, with
the back edge of the rain shield nearly coincident with low level
temps necessary to support snow.
Over the next few hours...band of IFR cigs beneath and west of
the low should sweep into STL Metro TAFS with rain
continuing. Precip here should generallly remain liquid, although
a very brief switch to snow may occur by mid morning before the
precip comes to an end. Meanwhile, at KUIN and KCOU it appears
that low level AMS is just now getting cold enough to support
snow, and there could be a brief period of IFR vsbys with this
brief shot of snow. Ceilings will lift into the MVFR range by
midday, with this cloud deck then clearing from west to east
during the afternoon.
Northwest winds will be gusting to around 35kts throughout the
morning in the wake of the low, with a gradual decrease in speeds
expected during the afternoon.
Specifics for KSTL: IFR cigs will develop/advect into the area
shortly, with the rain possibly changing over to a brief period of
snow before ending around mid morning. As surface low pulls away,
cigs should increase into the MVFR range from late morning into
the afternoon, with this cloud deck clearing by sunset.
Winds will increase rapidly over the next few hours, and expect
northwest winds to gust to around 35kts from mid morning into
early afternoon, with a slow decrease heading into the early
evening hours.
Truett
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
431 AM CST SAT NOV 21 2015
.SHORT TERM: (Through Tonight)
Issued at 255 AM CST Sat Nov 21 2015
Ongoing precipitation will continue through early afternoon,
eventually tapering off from west to east due to strong
subsidence behind a cold front. A few snowflakes could mix in
with the rain at times almost anywhere across the CWA, especially
just as the rain is ending because that is when the colder air
will also be arriving. However, only the far northern CWA appears
to stay cold enough for long enough to see any accumulation, and
likely only a dusting at best.
Strong CAA behind the aforementioned cold front will produce
falling temperatures during the day across most of the area. The
exception may be across the far eastern CWA where temperatures
could remain steady or perhaps rise by a degree or two before the
front arrives.
Very windy conditions are expected today, especially for the
first few hours after fropa. A tight pressure gradient will lead
to sustained winds of 15-25 mph, and stronger winds aloft will mix
down and produce gusts of 30-40 mph. These values are consistent
with upstream METARs early this morning. BUFKIT soundings from
the RAP and the NAM do suggest that the wind gusts could even be
a bit higher than currently forecast, which would approach
criteria for a wind advisory. However, it does not appear that
wind gusts of that magnitude will be widespread enough to warrant
issuing a wind advisory, therefore no wind headlines are planned
attm. The next shift may revisit the need for wind headlines based
on observational trends. Winds should diminish quickly this
evening.
The coldest temperatures of the season so far are expected
tonight and early tomorrow morning. Overnight lows will likely
drop into the upper teens to lower 20s across the area. Overnight
temperatures would be even lower if it weren`t for the expected
mid/high clouds ahead of a secondary vort max dropping through the
upper trough tonight. These clouds will interfere with radiational
cooling processes.
Kanofsky
.LONG TERM: (Sunday through Friday)
Issued at 255 AM CST Sat Nov 21 2015
A surface high pressure center will be located south of the area
this weekend, keeping winds from the west or west-southwest until
the surface ridge moves farther eastward during the early or
middle part of the week. At that point, winds will likely become
southerly ahead of a developing low pressure system, bringing
warmer air back into the region. Unlike the 00z runs on the last
two days, the current ECMWF/GFS/GEM 00z model runs are in
remarkably good agreement on large scale atmospheric features
through 00z Wed. The primary features of interest are a large,
complex low pressure system over NV/UT and broad southwesterly
flow aloft over MO/IL. Model solutions quickly diverge thereafter,
and confidence in the forecast beyond Tuesday is low.
Kanofsky
&&
.AVIATION: (For the 06z TAFs through 06z Saturday Night)
Issued at 1127 PM CST Fri Nov 20 2015
Occasional light rain will affect the terminals overnight
tonight. Ceilings should quickly lower later tonight at KCOU and
KUIN behind the inverted trough from VFR down to IFR. Still
thinking a changeover from rain to snow at KUIN around 1200 UTC
and KCOU at 1300 UTC. Northwest winds will be quite gusty during
Saturday morning...on the order of 30-35 knots. Ceilings will be
slow to improve during the day on Saturday but do look to scatter
out by late Saturday afternoon along with winds becoming lighter.
A clear sky and light NW winds are expected for Saturday night.
Specifics for KSTL:
Occassional light rain will affect the terminal overnight
tonight. Ceilings should quickly lower toward 1200 UTC from VFR
down to IFR behind after surface low passes just to south of KSTL.
Northwest winds will be quite gusty as well by late Saturday
morning...on the order of 30-35 knots. Cannot rule out some wet
snowflakes mixing in with rain or some flurries toward tail end of
precipitation...but left mention out for now. Ceilings will be
slow to improve during the day on Saturday but do look to scatter
out around 2100 UTC Saturday afternoon along with winds becoming
lighter. A clear sky and light NW winds are expected for Saturday
night.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1120 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 826 PM CST FRI NOV 20 2015
FORECAST WAS UPDATED TO CLEAR HEADLINES...AND REMOVE ALL MENTION
OF PRECIPITATION TONIGHT EXCEPT FOR WHAT IS STILL MOVING THROUGH
THE FAR SOUTHEAST CORNER OF THE FORECAST AREA...BUT EVEN THAT
SHOULD BE DONE SOON. ALSO ADJUSTED TEMPERATURES AND WINDS FOR
TONIGHT BASED ON LATEST OBSERVATIONS. A FEW FLURRIES MAY STILL BE
REPORTED THIS EVENING BUT NO REDUCTIONS TO VISIBILITY EXPECTED.
AT 0230Z THERE WAS ANOTHER SMALL BAND OF VERY LIGHT SNOW OVER THE
NEBRASKA PANHANDLE WITH CHADRON DOWN TO 1.25 MI AND 1 MILE AT
SCOTTS BLUFF. THE 01Z RUNS OF THE THE OPERATIONAL AND
EXPERIMENTAL HRRR BRING THIS LIGHT BAND INTO NORTH CENTRAL-SOUTHWEST
NEBRASKA BY 09Z. THESE MODELS INDICATE THAT BAND SHOULD DISSIPATE
BEFORE MOVING INTO EASTERN NEBRASKA...BUT WE WILL KEEP ON EYE ON
THE TRENDS.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 230 PM CST FRI NOV 20 2015
SNOW CONTINUES TO FALL ACROSS NORTHERN PARTS OF THE AREA EARLY
THIS AFTERNOON WITH HIGHEST AMOUNTS REPORTED ALONG THE NORTHERN
BORDER WHERE SNOW HAS BEEN PERSISTENT SINCE THIS MORNING. LATEST
REGIONAL RADARS SHOW BACK EDGE OF SNOW MOVING QUICKLY EAST INTO
NORTHEAST NEBRASKA AT 19Z WITH COLD FRONT PUSHING SOUTH TOWARD
SOUTHEAST NEBRASKA. MAIN SNOW BAND HAS BEEN ORIENTED ALONG
600-700MB AXIS OF FRONTOGENETIC FORCING SINCE THIS MORNING WITH A
SECONDARY BAND OF PRECIP OVER SOUTHWEST IOWA ALONG THE 800-900MB
AXIS. LATEST SHORT RANGE MODELS SHOW THE MID LEVEL FORCING
BECOMING LESS FOCUSED ALONG THE NORTHERN BORDER AND DRIFTING TO
THE SOUTHEAST THROUGH THE EVENING WHILE LOW LEVEL FORCING DROPS
INTO KANSAS AND MISSOURI AS THE COLD AIR MOVES INTO THE AREA.
WILL CONTINUE WITH CURRENT HEADLINES FOR NOW SINCE WINDS WILL BE
PICKING UP BEHIND THE FRONT. CURRENT SNOW AMOUNTS AND ORIENTATION
ALSO LOOKS PRETTY GOOD WITH AMOUNTS DROPPING OFF QUICKLY SOUTH OF
THE PLATTE RIVER INTO SOUTHWEST CORNER OF IOWA. SYSTEM SHOULD BE
PRETTY MUCH OUT OF THE AREA BY MID TO LATE EVENING.
A PERIOD OF DRY WEATHER FOLLOWS BEHIND THIS SYSTEM FOR SATURDAY INTO
MONDAY. COLD TEMPERATURES WILL BE THE RULE THROUGH SUNDAY MORNING
THEN MODERATING A BIT INTO EARLY NEXT WEEK.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 230 PM CST FRI NOV 20 2015
FIRST PART OF THE WEEK STARTS OFF SEASONAL AND DRY BUT ANOTHER
STORM SYSTEM FROM MID TO LATE WEEK WILL BRING THE CHANCE OF MORE
WINTER WEATHER TO A LARGE PART OF THE REGION FOR THE THANKSGIVING
HOLIDAY.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1120 PM CST FRI NOV 20 2015
WINDS WILL SLOWLY DECREASE OVERNIGHT. CURRENT CIGS FROM 1000 TO
2000 FEET WILL LIFT AND BECOME VFR. STILL SOME POTENTIAL FOR SOME
FLURRIES OVERNIGHT BUT GENERALLY SHOULD NOT RESTRICT VSBY BELOW
6 MILES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...NIETFELD
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1107 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 655 PM CST FRI NOV 20 2015
SENT AN UPDATE OUT FOR THIS EVENING...CURTAILING SNOW EARLIER BY 9
AM FOR ALL AREAS AS THE HRRR SEEMS TO HAVE THE BEST GRIP ON LATEST
PRECIPITATION TRENDS AS WELL AS THE RADAR INDICATING THAT MOST
PRECIPITATION IS OUT OF OUR CWA.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 319 PM CST FRI NOV 20 2015
THE MAIN CONCERNS IN THE SHORT TERM FORECAST PERIOD ARE ACTUALLY IN
THE VERY NEAR TERM AS A LARGE UPPER LEVEL DISTURBANCE IS BRINGING
ONGOING PRECIPITATION TO PORTIONS OF NEBRASKA. OTHERWISE THE
REMAINDER OF SHORT TERM IS FAIRLY QUIET AND SEASONABLY COLD.
FOR THE REST OF TODAY...THE UPPER LEVEL TROUGH WILL CONTINUE TO
SURGE EASTWARD ACROSS THE PLAINS...AS A DAUNTING COLD FRONTAL
BOUNDARY SINKS QUICKLY SOUTHEAST. LATEST RADAR TRENDS HAS INDICATED
POCKETS OF HEAVIER PRECIPITATION REMAINING WELL TO THE NORTH OF
INTERSTATE 80 WITH ONLY LIGHT SCATTERED RADAR RETURNS ACROSS THE TRI-
CITIES. OBSERVATIONS AROUND MID AFTERNOON SHOW THE FRONTAL BOUNDARY
HAS SAGGED AS FAR SOUTH AS THE TRI-CITIES. FORECAST SNOW AMOUNTS
COULD BE A BIT HIGH FOR PORTIONS OF POLK COUNTY THIS EVENING.
CHANCES FOR PRECIPITATION WILL LAST THE LONGEST FOR THAT COUNTY AS
THE SYSTEM EXITS. HOWEVER...TEMPERATURES WILL NEED TO WET BULB DOWN
CLOSER TO FREEZING FOR SNOW TO MATERIALIZE. THIS HAPPENED RATHER
QUICKLY ACROSS PORTIONS OF VALLEY AND GREELEY COUNTIES BUT
CONFIDENCE IS RATHER SHAKY FURTHER SOUTHEAST. THUS SNOW AMOUNTS MAY
ACTUALLY BE LOWER THAN FORECAST.
THE COLD FRONT WILL CONTINUE TO SURGE SOUTH THIS EVENING WITH STRONG
NORTHERLY WINDS BEHIND THE FRONT. THIS INCREASED GUSTS COULD LAST
WELL INTO THE OVERNIGHT HOURS BEFORE DECREASING NEAR SUNRISE.
THE FRONT WILL USHER IN MUCH COLDER AIR...IN FACT...PROBABLY THE
COLDEST OF THE SEASON SO FAR. HIGH TEMPERATURES TOMORROW WILL
STRUGGLE TO REACH THE MID TO UPPER 30S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 319 PM CST FRI NOV 20 2015
A COLD SURFACE HIGH PRESSURE SYSTEM WILL SLIDE TO THE SOUTHEAST
SATURDAY NIGHT. TEMPERATURES WILL CONTINUE TO BE COLD SATURDAY
NIGHT. BY SUNDAY MORNING THE WINDS ARE TURNING TO THE WEST AND WITH
WARM ADVECTION AND DOWN SLOPE WINDS...TEMPERATURES SHOULD RECOVER
PRETTY EASILY INTO THE MID 40S TO AROUND 50. WILL HAVE TO WATCH TO
SEE HOW MUCH SNOW FALLS THIS AFTERNOON AND IF IT WILL HAVE ANY
EFFECT ON THE TEMPERATURES ON SUNDAY.
SUNDAY NIGHT THROUGH TUESDAY A WEAK UPPER LEVEL RIDGE MOVES OVER THE
AREA. THE SURFACE HIGH MOVES TO THE EAST AND A SURFACE LOW DEVELOPS
ON THE HIGH PLAINS. WITH WARM ADVECTION AND WINDS TURNING FROM WEST
TO SOUTH...WILL CONTINUE WITH THE WARM TEMPERATURES. READINGS IN THE
50S ARE POSSIBLE DURING THE DAY.
AN UPPER LEVEL WAVE STARTS TO APPROACH THE FORECAST AREA TUESDAY
NIGHT INTO WEDNESDAY. WITH THE SOUTH WINDS ACROSS THE AREA MONDAY
AND TUESDAY THERE IS SOME MOISTURE THAT MOVES NORTH INTO THE
AREA...MOSTLY IN THE EAST. BY WEDNESDAY THE UPPER WAVE IS AFFECTING
THE AREA ENOUGH THAT WITH THE MOISTURE...THERE IS A SMALL CHANCE FOR
SOME LIGHT RAIN...MAINLY NORTH AND EAST IN THE AREA. A COLD FRONT
MOVES INTO THE AREA WEDNESDAY AFTERNOON AND EVENING. THE COLD AIR IS
A LITTLE BEHIND THE FRONT AND DURING THE AFTERNOON EXPECT RAIN.
THE UPPER LEVEL WAVE MOVES INTO THE AREA WEDNESDAY NIGHT AND THE
COLD FRONT MOVES TO THE SOUTH. BY WEDNESDAY NIGHT THE TEMPERATURES
START TO COOL OFF ENOUGH THAT THE PRECIPITATION SHOULD MIX WITH SNOW
FOR MUCH OF THE AREA THEN CHANGE TO SNOW IN THE NORTHWEST. THE
NORTHWEST SHOULD BE COLD ENOUGH DURING THE DAY THURSDAY TO KEEP
SNOW...BUT PORTIONS OF THE AREA COULD HAVE A MIX WITH MOSTLY RAIN IN
THE SOUTHEAST. COLDER AIR CONTINUES TO PUSH INTO THE AREA AND HAVE A
CHANCE FOR SNOW BOTH THURSDAY NIGHT AND FRIDAY. THAT IS THE CURRENT
THINKING. THE ONE MAIN WRENCH IN ALL OF THIS IS THERE IS A TIGHT
TEMPERATURE GRADIENT AT 850MB AS IT MOVES THROUGH THE AREA. THE
CHANGE FROM RAIN TO SNOW COULD CHANGE QUITE A BIT AS THE COLD AIR
COMES IN. ALSO...IF THE TIMING IS OFF A LITTLE BIT IT COULD MAKE
PHASE CHANGE TIMING DIFFERENT AS WELL.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1055 PM CST FRI NOV 20 2015
NORTH WINDS WILL BE GUSTY FOR THE MAJORITY OF THE NIGHT BEFORE
SUBSIDING TOWARDS DAYBREAK ON SATURDAY AS THE SFC GRADIENT RELAXES
AS HIGH PRESSURE SETTLES ONTO THE PLAINS. CANNOT COMPLETELY RULE
OUT A FLURRY POTENTIAL BRIEFLY TONIGHT BUT CHCS ARE FAIRLY
MINIMAL. MVFR CIGS WILL INCREASE TO VFR SATURDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HEINLEIN
SHORT TERM...SALTZMAN
LONG TERM...JCB
AVIATION...FAY
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1249 PM EST SAT NOV 21 2015
.SYNOPSIS...
LOW PRESSURE WILL LIFT NORTHEAST ACROSS THE GREAT LAKES TODAY
WITH A TRAILING COLD FRONT SWEEPING EAST ACROSS THE REGION THIS
AFTERNOON. RAIN SHOWERS WILL CHANGE TO SNOW SHOWERS OR FLURRIES
BEFORE ENDING TONIGHT. MUCH COLDER AIR WILL SETTLE IN BEHIND THE
FRONT FOR THE END OF THE WEEKEND. A WARMING TREND WILL THEN RETURN
BY THE FIRST OF THE WEEK INTO THE THANKSGIVING HOLIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONLY MINOR CHANGES TO GRIDS THIS MORNING AS SURFACE LOW STILL
REMAINS ON TRACK TO BE AROUND KDAY AT 18Z. CURRENT SURFACE
ANALYSIS FROM THIS MORNING SHOWS THE SURFACE LOW CURRENTLY IN
SOUTHERN ILLINOIS WITH A COLD FRONT TRAILING OFF TO THE
SOUTHEAST. THERE WAS ALSO A WEAK WARM FRONT ACROSS NORTHERN
KENTUCKY. DEWPOINTS NORTH OF THE COLD FRONT WERE MAINLY AROUND 20
DEGREES WHILE SOUTH OF THE WARM FRONT AT OR ABOVE 30 DEGREES. KILN
12Z SOUNDING ALSO SHOWS A GOOD DEAL OF DRY AIR BETWEEN 700 AND
1000 MB. FORECAST SOUNDINGS SHOW THE LAYER SLOWLY SATURATING WITH
WEAK WET BULBING FIGHTING WAA AS THE WARM FRONT PUSHES NORTH.
LOOKING AT RAP CRITICAL THICKNESSES IT SEEMS LIKE MOST OF THE
AREA WILL INITIALLY BE RAIN EXCEPT FOR THE POSSIBILITY OF OUR FAR
NORTHERN COUNTIES (DEPENDING ON THE EXACT TRACK OF THE SURFACE LOW
AND WARM FRONT). AS THE FRONT PASSES THERE WILL BE A BRIEF PERIOD
OF RAIN CHANGING OVER TO A RAIN/SNOW MIX AND THEN SNOW. DRIER MID
LEVEL AIR WILL THEN QUICKLY MOVE IN BEHIND THE FRONT. FORECAST
SOUNDINGS STILL SHOW LOW LEVEL SATURATION WHICH WOULD SUPPORT
FLURRIES BEHIND THE FRONT. WIND GUSTS UP TO 35 MPH CAN ALSO BE
EXPECTED ALONG AND BEHIND THE FRONT.
PREV DISCUSSION ->
MID LEVEL ENERGY DROPPING SE INTO THE PLAINS WILL ACT TO SHARPEN
UP AND CARVE OUT A TROF OVER THE NATIONS MID SECTION. AN EMBEDDED
S/W TO ROTATE AROUND THE EAST SIDE OF THIS LONG WAVE TROF THRU THE
MID MS VLY THIS MORNING AND INTO THE GREAT LAKES BY EVENING.
ASSOCIATED SFC LOW OVER THE MID MS VLY TO EJECT NE INTO SW OHIO BY
18Z AND THEN INTO THE EASTERN GREAT LAKES BY EVENING. NUMERICAL
MODEL SOLNS HAVE CLUSTERED COMING INTO BETTER AGREEMENT WITH SFC
LOW NEAR JUST WEST OF DAYTON AT 18Z. COMPARED TO THE 12Z
RUNS...THESE SOLNS HAVE GENERALLY TRENDED FURTHER SOUTH CLOSER TO
THE CONSISTENT ECMWF...ALLOWING FOR A QUICKER CHANGE OVER AND A
LTL MORE SNOW. WILL ALLOW PCPN TO DEVELOP BY AFTN ACROSS THE
WESTERN COUNTIES AND SPREAD EAST. STRONG CAA DEVELOPS WITH 8H
TEMPS GOING FROM AT OR ABOVE 5 DEG C TO -6 DEG C IN THE WEST BY
00Z. WILL BUMP UP SNOW TO AROUND 1 INCH ACROSS THE FAR NW TO ABOUT
ONE TENTH OF AN INCH ON GRASSY AREAS AT ILN. WILL SHOW NON-
DIURNAL TEMPERATURE TREND WITH READINGS FALLING INTO THE 30S IN
THE WEST LATE IN THE DAY. EXPECT WEST WIND GUSTS UP TO 35 MPH WITH
THE FRONTAL PASSAGE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
STRONG SFC COLD FRONT EXPECTED TO PUSH THRU ILN/S EASTERN COUNTIES
DURG THE EARLY EVENING. STRONG CAA TO DEVELOP WITH 8H TEMPS TO
BETWEEN -8 AND -11 DEG C BY SUNDAY MORNING. EXPECT PCPN TO MIX
WITH AND CHANGE TO SNOW ACRS THE ENTIRE FA EARLY TONIGHT. BASED ON
BETTER AGREEMENT OF SOLNS MORE IN LINE WITH COLDER FURTHER SOUTH
ECMWF SOLN...HAVE INCREASED SNOW TO AROUND 1 INCH ACRS THE FAR NW
TO A TENTH OF AN INCH AT ILN. FURTHER SOUTH...EXPECT LITTLE OR NO
ACCUMULATION. EXPECT PCPN TO END OR DIMINISH TO FLURRIES BY LATE
EVENING. AS SFC LOW LIFTS NE INTO SE CANADA...EXPECT DRY SLOW TO
PUSH INTO SW OHIO. WILL ALLOW CLOUDS TO DECREASE ACRS THE WEST
LATE. THE COLDEST AIR OF THE SEASON WILL SETTLE INTO THE OHIO
VALLEY AS SFC HIGH PRESSURE BUILD INTO THE OHIO VALLEY SUNDAY.
EXPECT SAT NIGHTS LOWS TO RANGE FROM THE UPPER TEENS FAR NW TO THE
UPPER 20S SE. SUNDAY WILL OFFER COLD TEMPERATURES WITH A GOOD
AMOUNT OF SUNSHINE. EXPECT SUNDAYS HIGHS TO RANGE FROM THE UPPER
20S NW TO THE MID/UPR 30S SE. TEMPERATURES WILL MODERATE ON THE
BACK SIDE OF THE HIGH MONDAY WITH READINGS FROM NEAR 40 NW TO THE
MID 40S SE.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
UPPER LEVEL TROUGH WILL CROSS THE NORTHERN OHIO VALLEY EARLY MONDAY
AND INCREASE CLOUD COVER HERE WITH GENERALLY SUNNY SKIES TO THE
SOUTH. THE AXIS OF THE SURFACE HIGH WILL PASS EAST OF THE REGION
OVERNIGHT MONDAY AND RETURN FLOW WILL PERMIT A WARMING TREND FOR
NEXT WEEK.
MODELS DIVERGE SIGNIFICANTLY ON THURSDAY NIGHT AS A LONGWAVE TROUGH
RUNS FROM JAMES BAY CANADA TO CALIFORNIA AND A SURFACE FRONT LAYS
OUT FROM TX TO SOUTH OF HUDSON BAY. GFS IS PROGRESSIVE WITH THE
UPPER LOW AND PULLS THE SURFACE LOW INTO CANADA...SWEEPING THE FRONT
THROUGH THE OHIO VALLEY LATER FRIDAY AND OVERNIGHT. THE EUROPEAN
DISJOINTS THE UPPER SYSTEM AND CUTS OFF A H5 CLOSED LOW IN THE GREAT
BASIN WITH A SOMEWHAT PROGRESSIVE NORTHERN S/W PEELING OFF OF THIS
AND CROSSING THE GREAT LAKES OVERNIGHT FRIDAY. THIS KEEPS THE
SURFACE FRONT OVER THE MIDWEST AND PULLS ENERGY NORTHEAST AND AWAY
FROM THE OHIO VALLEY FOR FRIDAY AND OVERNIGHT.
BLENDED THE TWO BUT KEPT FORECAST AREA IN LOW CHANCE POPS ON
FRIDAY...INCREASING THEM BEYOND VALID FORECAST PERIOD.
FORECAST UNCERTAINTY ON FRIDAY IS HIGH AFTER THURSDAY NIGHT DUE TO
THESE DIFFERENCES IN MODELS. TEMPS AT THE END OF THE WEEK SHOULD
RISE INTO AT LEAST THE 50S AND COULD PULL INTO THE 60S IF THE DRIER
EUROPEAN VERIFIES. CLOUDY AND RAINY GFS VERIFICATION WILL LIMIT
HIGHS THIS DAY. TOOK A MIDDLE OF THE ROAD APPROACH BEING THIS FAR
OUT.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
SURFACE LOW PRESSURE CURRENTLY LOCATED JUST EAST OF KIND AT THIS
HOUR WITH SNOW BEING REPORTED NEAR THE LOW WITH MOSTLY RAIN BEING
REPORTED SOUTH OF THE LOW. THE LOW WILL CONTINUE TO TRACK OFF TO
THE ENE AND BE APPROACHING DAYTON IN THE NEXT COUPLE OF HOURS. AS
PRECIP MOVES INTO THE AREA WIDESPREAD MVFR CIGS CAN BE EXPECTED
WITH POCKETS OF IFR IN THE HEAVIER SHOWERS. A SURFACE COLD FRONT
WILL THEN PUSH THROUGH THE AREA BRINGING GUSTY WINDS ACROSS THE
TAF SITES. 850 MB WINDS ARE SHOWING AROUND 35 KTS (VIA GFS/ RAP)
AND WITH STRONG COLD AIR ADVECTION SOME OF THIS SHOULD BE ABLE TO
MIX DOWN. THERE WILL ALSO BE A SLIGHT WINDOW OF WHEN RAIN WILL START
TO MIX WITH SNOW. IN GENERAL AM NOT IMPRESSED WITH THE CHANCES OF
THIS THOUGH (ESP SOUTHERN TAF SITES) AS FORECAST SOUNDINGS QUICKLY
DRY OUT THE MID LEVELS. A LACK OF MOISTURE IN THE SNOW GROWTH
REGION WOULD FAVOR FLURRIES. TOMORROW AFTERNOON SURFACE HIGH
PRESSURE WILL MOVE INTO THE AREA ALLOWING THE AREA TO SLOWLY CLEAR
AND WINDS TO RELAX.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HAINES/AR
NEAR TERM...HAINES/AR
SHORT TERM...AR
LONG TERM...FRANKS
AVIATION...HAINES
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
959 AM EST SAT NOV 21 2015
.SYNOPSIS...
LOW PRESSURE WILL LIFT NORTHEAST ACROSS THE GREAT LAKES TODAY
WITH A TRAILING COLD FRONT SWEEPING EAST ACROSS THE REGION THIS
AFTERNOON. RAIN SHOWERS WILL CHANGE TO SNOW SHOWERS OR FLURRIES
BEFORE ENDING TONIGHT. MUCH COLDER AIR WILL SETTLE IN BEHIND THE
FRONT FOR THE END OF THE WEEKEND. A WARMING TREND WILL THEN RETURN
BY THE FIRST OF THE WEEK INTO THE THANKSGIVING HOLIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONLY MINOR CHANGES TO GRIDS THIS MORNING AS SURFACE LOW STILL
REMAINS ON TRACK TO BE AROUND KDAY AT 18Z. CURRENT SURFACE
ANALYSIS FROM THIS MORNING SHOWS THE SURFACE LOW CURRENTLY IN
SOUTHERN ILLINOIS WITH A COLD FRONT TRAILING OFF TO THE
SOUTHEAST. THERE WAS ALSO A WEAK WARM FRONT ACROSS NORTHERN
KENTUCKY. DEWPOINTS NORTH OF THE COLD FRONT WERE MAINLY AROUND 20
DEGREES WHILE SOUTH OF THE WARM FRONT AT OR ABOVE 30 DEGREES. KILN
12Z SOUNDING ALSO SHOWS A GOOD DEAL OF DRY AIR BETWEEN 700 AND
1000 MB. FORECAST SOUNDINGS SHOW THE LAYER SLOWLY SATURATING WITH
WEAK WET BULBING FIGHTING WAA AS THE WARM FRONT PUSHES NORTH.
LOOKING AT RAP CRITICAL THICKNESSES IT SEEMS LIKE MOST OF THE
AREA WILL INITIALLY BE RAIN EXCEPT FOR THE POSSIBILITY OF OUR FAR
NORTHERN COUNTIES (DEPENDING ON THE EXACT TRACK OF THE SURFACE LOW
AND WARM FRONT). AS THE FRONT PASSES THERE WILL BE A BRIEF PERIOD
OF RAIN CHANGING OVER TO A RAIN/SNOW MIX AND THEN SNOW. DRIER MID
LEVEL AIR WILL THEN QUICKLY MOVE IN BEHIND THE FRONT. FORECAST
SOUNDINGS STILL SHOW LOW LEVEL SATURATION WHICH WOULD SUPPORT
FLURRIES BEHIND THE FRONT. WIND GUSTS UP TO 35 MPH CAN ALSO BE
EXPECTED ALONG AND BEHIND THE FRONT.
PREV DISCUSSION ->
MID LEVEL ENERGY DROPPING SE INTO THE PLAINS WILL ACT TO SHARPEN
UP AND CARVE OUT A TROF OVER THE NATIONS MID SECTION. AN EMBEDDED
S/W TO ROTATE AROUND THE EAST SIDE OF THIS LONG WAVE TROF THRU THE
MID MS VLY THIS MORNING AND INTO THE GREAT LAKES BY EVENING.
ASSOCIATED SFC LOW OVER THE MID MS VLY TO EJECT NE INTO SW OHIO BY
18Z AND THEN INTO THE EASTERN GREAT LAKES BY EVENING. NUMERICAL
MODEL SOLNS HAVE CLUSTERED COMING INTO BETTER AGREEMENT WITH SFC
LOW NEAR JUST WEST OF DAYTON AT 18Z. COMPARED TO THE 12Z
RUNS...THESE SOLNS HAVE GENERALLY TRENDED FURTHER SOUTH CLOSER TO
THE CONSISTENT ECMWF...ALLOWING FOR A QUICKER CHANGE OVER AND A
LTL MORE SNOW. WILL ALLOW PCPN TO DEVELOP BY AFTN ACROSS THE
WESTERN COUNTIES AND SPREAD EAST. STRONG CAA DEVELOPS WITH 8H
TEMPS GOING FROM AT OR ABOVE 5 DEG C TO -6 DEG C IN THE WEST BY
00Z. WILL BUMP UP SNOW TO AROUND 1 INCH ACROSS THE FAR NW TO ABOUT
ONE TENTH OF AN INCH ON GRASSY AREAS AT ILN. WILL SHOW NON-
DIURNAL TEMPERATURE TREND WITH READINGS FALLING INTO THE 30S IN
THE WEST LATE IN THE DAY. EXPECT WEST WIND GUSTS UP TO 35 MPH WITH
THE FRONTAL PASSAGE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
STRONG SFC COLD FRONT EXPECTED TO PUSH THRU ILN/S EASTERN COUNTIES
DURG THE EARLY EVENING. STRONG CAA TO DEVELOP WITH 8H TEMPS TO
BETWEEN -8 AND -11 DEG C BY SUNDAY MORNING. EXPECT PCPN TO MIX
WITH AND CHANGE TO SNOW ACRS THE ENTIRE FA EARLY TONIGHT. BASED ON
BETTER AGREEMENT OF SOLNS MORE IN LINE WITH COLDER FURTHER SOUTH
ECMWF SOLN...HAVE INCREASED SNOW TO AROUND 1 INCH ACRS THE FAR NW
TO A TENTH OF AN INCH AT ILN. FURTHER SOUTH...EXPECT LITTLE OR NO
ACCUMULATION. EXPECT PCPN TO END OR DIMINISH TO FLURRIES BY LATE
EVENING. AS SFC LOW LIFTS NE INTO SE CANADA...EXPECT DRY SLOW TO
PUSH INTO SW OHIO. WILL ALLOW CLOUDS TO DECREASE ACRS THE WEST
LATE. THE COLDEST AIR OF THE SEASON WILL SETTLE INTO THE OHIO
VALLEY AS SFC HIGH PRESSURE BUILD INTO THE OHIO VALLEY SUNDAY.
EXPECT SAT NIGHTS LOWS TO RANGE FROM THE UPPER TEENS FAR NW TO THE
UPPER 20S SE. SUNDAY WILL OFFER COLD TEMPERATURES WITH A GOOD
AMOUNT OF SUNSHINE. EXPECT SUNDAYS HIGHS TO RANGE FROM THE UPPER
20S NW TO THE MID/UPR 30S SE. TEMPERATURES WILL MODERATE ON THE
BACK SIDE OF THE HIGH MONDAY WITH READINGS FROM NEAR 40 NW TO THE
MID 40S SE.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER LEVEL TROUGH WILL CROSS THE NORTHERN OHIO VALLEY EARLY MONDAY
AND INCREASE CLOUD COVER HERE WITH GENERALLY SUNNY SKIES TO THE
SOUTH. THE AXIS OF THE SURFACE HIGH WILL PASS EAST OF THE REGION
OVERNIGHT MONDAY AND RETURN FLOW WILL PERMIT A WARMING TREND FOR
NEXT WEEK.
MODELS DIVERGE SIGNIFICANTLY ON THURSDAY NIGHT AS A LONGWAVE TROUGH
RUNS FROM JAMES BAY CANADA TO CALIFORNIA AND A SURFACE FRONT LAYS
OUT FROM TX TO SOUTH OF HUDSON BAY. GFS IS PROGRESSIVE WITH THE
UPPER LOW AND PULLS THE SURFACE LOW INTO CANADA...SWEEPING THE FRONT
THROUGH THE OHIO VALLEY LATER FRIDAY AND OVERNIGHT. THE EUROPEAN
DISJOINTS THE UPPER SYSTEM AND CUTS OFF A H5 CLOSED LOW IN THE GREAT
BASIN WITH A SOMEWHAT PROGRESSIVE NORTHERN S/W PEELING OFF OF THIS
AND CROSSING THE GREAT LAKES OVERNIGHT FRIDAY. THIS KEEPS THE
SURFACE FRONT OVER THE MIDWEST AND PULLS ENERGY NORTHEAST AND AWAY
FROM THE OHIO VALLEY FOR FRIDAY AND OVERNIGHT.
BLENDED THE TWO BUT KEPT FORECAST AREA IN LOW CHANCE POPS ON
FRIDAY...INCREASING THEM BEYOND VALID FORECAST PERIOD.
FORECAST UNCERTAINTY ON FRIDAY IS HIGH AFTER THURSDAY NIGHT DUE TO
THESE DIFFERENCES IN MODELS. TEMPS AT THE END OF THE WEEK SHOULD
RISE INTO AT LEAST THE 50S AND COULD PULL INTO THE 60S IF THE DRIER
EUROPEAN VERIFIES. CLOUDY AND RAINY GFS VERIFICATION WILL LIMIT
HIGHS THIS DAY. TOOK A MIDDLE OF THE ROAD APPROACH BEING THIS FAR
OUT.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
TAF SITES WILL STAY UNDER VFR THROUGH THE EARLY PART OF THE
FORECAST AS HIGH PRESSURE MOVES EAST. CONDITIONS WILL DETERIORATE
AFTER 18Z WHEN RAIN SHOWERS WITH MVFR WILL MOVE IN AHEAD OF A
STRONG COLD FRONT. SNOW SHOWERS WITH MVFR ARE LIKELY STARTING AT
22Z WHEN COLDER AIR ARRIVES WITH FRONTAL PASSAGE AND A WIND SHIFT
TO WEST. GUSTS OVER 30 KNOTS WILL BE POSSIBLE ALONG AND BEHIND THE
FRONT ESPECIALLY AT DAY. SNOW SHOWERS WILL END AND WINDS WILL
SLOWLY SUBSIDE AFTER 02Z SUNDAY. CVG WILL SEE SCT CLOUDS AND
DECREASING NORTHWEST WINDS AFTER 12Z SUNDAY.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HAINES/AR
NEAR TERM...HAINES/AR
SHORT TERM...AR
LONG TERM...FRANKS
AVIATION...CONIGLIO
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
953 AM EST SAT NOV 21 2015
.SYNOPSIS...
A COLD FRONT CROSSES TONIGHT...MAKING THE SECOND HALF OF THE
WEEKEND MUCH COLDER THAN THE FIRST...WITH MAINLY MOUNTAIN SNOW
SHOWERS. HIGH PRESSURE NEXT WEEK WITH MODERATING TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
945 AM UPDATE...
RAISED TEMPS A FEW DEGREES THIS AFTN OVER THE LOWLANDS. WINDS WILL
PICK UP AHEAD OF THE FRONT AND ESPECIALLY JUST BEHIND THE FRONT
WHERE BUFKIT AND HRRR SUGGESTS 30 TO 35 KT GUSTS THIS EVENING.
AS FOR FIRE CONCERNS...THERE MAY BE ENOUGH OF A REBOUND IN RH
THIS AFTERNOON AS THE WINDS PICK UP TO MITIGATE NEEDING A FIRE
SPS. WILL CONTINUE TO MONITOR TRENDS OVER THE NEXT FEW HRS.
PREV DISCN...
LOW PRESSURE CENTER APPROACHES FROM THE LOWER OHIO
VALLEY TODAY. IT TAKES A LEFT HAND TURN THIS AFTERNOON...REACHING
THE UPPER OHIO VALLEY THIS EVENING...AS ITS ASSOCIATED UPPER LEVEL
S/W TROUGH ROUNDS THE BASE OF THE L/W TROUGH AND STARTS COMING UP
THE E SIDE...TAKING ON A NEGATIVE TILT AS A RESULT. THE SYSTEM IS
PROGGED TO DEEPEN TO THE TUNE OF ABOUT 6 MB / HR THIS AFTERNOON
AND TONIGHT...CROSSING SERN ONTARIO AND MOVING INTO SWRN QUEBEC
TONIGHT.
THE WARM FRONT AHEAD OF THE APPROACHING LOW LIFTS NWD THROUGH THE
AREA THIS MORNING AND MIDDAY...THE ASSOCIATED MID AND HIGH CLOUD
RETREATING NWD WELL AHEAD OF THE SFC FRONT FIRST THING THIS
MORNING. THIS PLACES THE FCST AREA IN THE WARM SECTOR THIS
AFTERNOON. EXITING DRY AIR WILL RESULT IN RH VALUES DIPPING INTO
THE 20S THIS AFTERNOON ACROSS CENTRAL AND NRN WV. WITH GUSTY WARM
SECTOR WINDS THIS AFTERNOON...AND DRYING FUELS...A FIRE DANGER
STATEMENT MAY BE NEEDED...AND THE LOW PROB HWO MENTION WILL
CONTINUE FOR THIS.
SHOWERS ARRIVE JUST AHEAD OF THE COLD FRONT THIS EVENING. COLDER
AIR RUSHES IN BEHIND THE SYSTEM WITH SHARP PRESSURE RISES BEHIND
THE COLD FRONT...ENDING THE PRECIPITATION AS IT ARRIVES. THEREFORE
SEE A VERY NARROW WINDOW OF OPPORTUNITY FOR A FEW SNOW FLAKES OVER
THE LOWLANDS AS THE SHOWERS END...MORE SO N THAN S IF ANYTHING.
THERE IS...OF COURSE...A BETTER CHANCE FOR SNOW IN THE MOUNTAINS
TONIGHT...ESPECIALLY ACROSS THE HIGHER TERRAIN...AS UPSLOPE
ENHANCES LOW LEVEL LIFT DURING THE COLD ADVECTION. AMOUNTS WILL BE
LIMITED BY LACK OF DENDRITIC GROWTH...AS IT WILL TAKE THE UPSLOPE
FLOW OVER THE MOUNTAINS JUST TO GET THE TOP OF THE SATURATED UP
INTO THE -8C AND COLDER LAYER. THOUGHT OVERNIGHT POPS MAY HAVE
BEEN A BIT HIGH FOR THIS REASON BUT OPTED TO LEAVE AS IS. HAVE CUT
BACK ON SNOW AMOUNTS TO UNDER AN INCH EVEN ACROSS THE HIGHEST
RIDGES...MAYBE A TRACE ON NRN LOWLAND HILLTOPS.
USED A MET/MAV/PREV BLEND FOR HIGHS IN THE WARM SECTOR TODAY...AND
A NAM/MET/PREV BLEND FOR HOURLY TEMPERATURES TONIGHT AS THE
BAROCLINIC ZONE MOVES THROUGH...A LITTLE SLOWER ON THE COOLING
THAN PREVIOUS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
FRONT WILL BE THROUGH CWA WITH COLD AIR ADVECTION TAKING PLACE
DURING THE DAY ON SUNDAY AND CONTINUING SUNDAY NIGHT. SURFACE
HIGH PRESSURE BEGINS BUILDING IN FROM THE WEST. 5H TROUGH...WITH
85H THERMAL TROUGH FOLLOWING...WILL MOVE THROUGH DURING THE DAY
SUNDAY. LOW LEVELS DRY OUT FAIRLY QUICKLY...HOWEVER RESIDUAL
MOISTURE WITH SOME ENHANCED DYNAMICS WILL HANG ON TO ALLOW FOR THE
CONTINUATION OF A FEW SNOW SHOWERS...PERHAPS ENDING BY SUNDAY
AFTERNOON. ATMOSPHERIC COLUMN WILL CONTINUE DRYING TREND FOR THE
REST OF THE PERIOD WITH NORTHWEST FLOW USHERING COOLER AIR. WILL
SEE SOME OF THE COLDEST TEMPERATURES MONDAY MORNING. FOR
TEMPS...USED MODEL BLEND ACROSS THE BOARD...AVERAGING VALUES BACK
INTO INHERITED FORECAST.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
MODELS AND ENSEMBLES SHOWING HIGH PRESSURE OVER THE AREA FOR MONDAY
NIGHT THROUGH THURSDAY NIGHT. NEXT SYSTEM ARRIVES LATE IN THE WEEK
OR NEXT WEEKEND. CONFIDENCE IN TIMING OF THIS COLD FRONT IS LOW.
USED A BLEND OF THE GEFS AND ECMWF ENSEMBLE MEANS.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
VFR THROUGH TODAY YIELDS TO MVFR CONDITIONS FROM W TO E
TONIGHT...AS A LOW PRESSURE SYSTEM APPROACHES FROM THE LOWER OHIO
VALLEY. ITS WARM FRONT WILL MOVE NWD THROUGH THE AREA DURING THE
MORNING AND MIDDAY HOURS TODAY. THE LOW ITSELF WILL TAKE A LEFT
HAND TURN THIS AFTERNOON AND REACH THE UPPER OHIO VALLEY BY THIS
EVENING. THIS WILL BRING ITS COLD FRONT TO THE OHIO RIVER NEAR
00Z SUN AND THEN THROUGH THE MOUNTAINS BY 06Z SUN.
SHOWERS WILL ARRIVE JUST AHEAD OF...IF NOT WITH...THE COLD
FRONT...THIS EVENING...LIKELY BRINGING VSBYS DOWN TO MVFR AND
THEN CIGS DOWN TO MVFR AN HOUR OR TWO AFTER THE COLD FRONT PASSES.
THE RAIN SHOWERS WILL SWITCH OVER TO SNOW SHOWERS OVER THE
MOUNTAINS OVERNIGHT TONIGHT. VSBYS WILL IMPROVE TO VFR FROM W TO E
OVERNIGHT AS THE PRECIPITATION ENDS.
LIGHT E TO SE FLOW AHEAD OF THE WARM FRONT THIS MORNING WILL
BECOME S TO SW AND GUSTY IN THE WARM SECTOR AHEAD OF THE COLD
FRONT THIS AFTERNOON AND EVENING...AND THEN W TO SW AND STILL A
BIT GUSTY BEHIND THE COLD FRONT TONIGHT...THEN W TO NW AND
DIMINISHING A BIT TOWARD DAWN SUN. LIGHT SW FLOW ALOFT THIS
MORNING WILL BECOME MODERATE SW THIS AFTERNOON...SHIFTING TO
MODERATE W BEHIND THE COLD FRONT TONIGHT...AND THEN LIGHT TO
MODERATE NW BY DAWN SUN.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: ONSET AND EXTENT OF MVFR IN RAIN SHOWERS AND
CIGS MAY VARY LATE TODAY AND TONIGHT. GUSTY WINDS WILL VARY LATER
TODAY AND TONIGHT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 15 16 17 18 19 20 21 22 23 00 01 02
EST 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY H H H H H H H H H H H M
HTS CONSISTENCY H H H H H H H H H M M H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KMC/TRM
NEAR TERM...TRM/30
SHORT TERM...KMC
LONG TERM...RPY
AVIATION...TRM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
518 PM EST SAT NOV 21 2015
.SYNOPSIS...
A FAST MOVING AREA OF LOW PRESSURE WILL RACE DOWN THE ST LAWRENCE
RIVER VALLEY TONIGHT AND SUNDAY...PUSHING A COLD FRONT ACROSS THE
REGION OVERNIGHT. A WEAK CLIPPER LOW WILL MOVE THROUGH NEW YORK
STATE MONDAY NIGHT...FOLLOWED BY A RIDGE OF HIGH PRESSURE THAT
WILL BUILD OVER THE OHIO VALLEY AND EASTERN US TUESDAY THROUGH
THANKSGIVING DAY. A NEW FRONTAL SYSTEM COULD BRING A RETURN OF
RAIN SHOWERS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
A BRIGHT DAY IS IN PROGRESS OVER MOST OF THE THE REGION AS THE
THICKER FRONTAL CLOUDS REMAIN OVER NWRN PA FOR THE TIME BEING.
RIDGE OF HIGH PRESSURE JUST TO OUR EAST WILL ENSURE DRY
CONDITIONS CONTINUING THROUGH THE DAYLIGHT HOURS. WE`LL SEE SERLY
WINDS MAINLY IN THE 10-20 MPH RANGE...WITH HIGHER GUSTS OF 20-25
MPH SUPPORTED OVER THE HIGHER ELEVATIONS.
THE COLD FRONT SHOULD BE ENTERING THE WESTERN STRIPE OF MY CWA
SHORTLY AFTER MIDNIGHT...AND BE EAST OF THE AREA BY SUNRISE. HRRR
TIMING SHOWS THE LEADING RAIN SHOWERS MOVING INTO THE AREA BETWEEN
ABOUT 10 PM AND MIDNIGHT...WITH COLD AIR CHANGING THE PRECIP TO
SNOW SHOWERS BETWEEN ABOUT MIDNIGHT AND 3 AM AS THE FRONT SWEEPS
EAST. THE BEST CHANCE FOR MEASURABLE PRECIP WILL BE OVER THE
WESTERN AND NORTHERN HIGH TERRAIN WITH SHORT RANGE GUIDANCE ALL
AGREEING IN SHOWING THE PRECIP SHIELD DIMINISHING IN COVERAGE AS
IT ENTERS CENTRAL AND EASTERN PA. OVER THESE CENTRAL AND EASTERN
AREAS VERY LIGHT RAIN SHOWERS WILL TAPER OFF AS LIGHT SNOW SHOWERS
OR FLURRIES VERY LATE TONIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
SUNDAY WILL TURN MARKEDLY COLDER AND BREEZY.
THE COLD AIR...WARM LAKES AND MEAN SFC-800MB 250-270 DEG WINDS
INDICATE A POTENTIAL FOR SINGLE LAKE ERIE SNOW BAND INITIALLY
ALONG THE I-90 CORRIDOR LATER TONIGHT AND SUNDAY MORNING...
TRANSITIONING INTO A MORE MULTI-BAND SETUP DURING THE DAY SUNDAY
INTO SUNDAY NIGHT. AT THIS TIME...LATEST OPERATIONAL MODELS AND
THE SREF IS SUGGESTING 2-4 INCHES OF SNOW POSSIBLE NEAR THE NY
BORDER WITH WARREN COUNTY...BUT BEST SNOW IS LIKELY JUST TO THE
NORTH OF THE PA/NY BORDER.
WE WILL CONTINUE OUR LES WATCH FOR NW WARREN COUNTY AT THIS TIME
WITH THE POTENTIAL FOR A FEW OF THE PERENNIAL SNOWBELT LOCATIONS
ACROSS FAR NW WARREN COUNTY PICKING UP MINIMAL WARNING CRITERIA
SNOWS OF 5-8 INCHES THROUGH MONDAY MORNING. THE REST OF WARREN AND
MCKEAN COUNTIES WOULD LIKELY SEE BETWEEN 1 AND 3 INCHES DURING
THIS SAME PERIOD.
SUNDAY WILL BE COLD AND BREEZY WITH FLURRIES AND A FEW SNOW
SHOWERS ACROSS THE LAURELS...AND AND PERHAPS A FEW LIGHT SNOW
SHOWERS OR FLURRIES BLEEDING INTO THE CENTRAL MOUNTAINS AT TIMES.
HIGH TEMPS WILL RANGE FROM NEAR 32 ACROSS THE NRN AND WRN
MOUNTAINS...AND UPPER 30S TO L40S ACROSS THE CENTRAL AND SE
VALLEY LOCATIONS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
LOOKING AT A SEE-SAW WEATHER PATTERN THIS PERIOD AS WE START OFF
THE PERIOD WITH A DEEPENING RELATIVE CHILL AS A SERIES OF
SHORTWAVE TROFS REINFORCE COOLER AIR ESTABLISHED OVER THE REGION
THIS WEEKEND...BEFORE THE START OF THE LONG TERM PERIOD. EARLY NEXT
WEEK THE PATTERN IS FORECAST TO TRANSITION TO A ZONAL FLOW THEN HEIGHTS
RISE OVER THE EASTERN U.S. IN RESPONSE TO A DIGGING UPPER TROF
OVER THE CENTRAL ROCKIES.
THE COLD AIR SHOULD SLOWLY EASE ON MONDAY INTO MONDAY NIGHT. WE
BOTTOM OUT -1 TO -1.5SD BELOW NORMAL FOR 850 MB TEMPS SUNDAY INTO
MONDAY EVENING.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
MAIN AVIATION CONCERN THIS EVENING WILL BE THE POSSIBILITY OF
LLWS...AS CORE OF STRONG WINDS ALOFT OVERSPREAD THE AREA IN
ADVANCE OF APPROACHING COLD FRONT. LATEST BUFKIT SOUNDINGS SUPPORT
A BRIEF PERIOD OF LLWS CRITERIA ACROSS MUCH OF CENTRAL PA LATE
THIS EVENING.
COLD FRONT WILL SWEEP THRU CENTRAL PA BTWN 04Z-07Z...ACCOMPANIED
BY A FEW SHRA ACROSS THE W MTNS. MVFR CONDS COULD ACCOMPANY THE
FRONTAL SHOWERS AT KBFD/KJST. HOWEVER...A BIGGER CONCERN MAY
STRONG...GUSTY WSW WINDS ACCOMPANYING AND IMMEDIATELY FOLLOWING
THE FRONTAL PASSAGE. HRRR AND LATEST NAM SOUNDINGS INDICATE THE
POSSIBILITY OF GUSTS BTWN 35-40KTS AT KBFD/KJST BTWN 04Z-07Z...WITH
SOMEWHAT WEAKER GUSTS FURTHER EAST.
COLD AIR FLOWING OVER THE GREAT LAKES WILL PRODUCE LAKE EFFECT
SNOW SHOWERS ACROSS PORTIONS OF NW PA LATE TONIGHT AND SUNDAY.
HOWEVER...LATEST MDL DATA SUGGESTS THE SIG VIS REDUCTIONS WILL
REMAIN JUST NORTHWEST OF KBFD. ELSEWHERE...WIDESPREAD VFR CONDS
APPEAR VERY LIKELY THRU SUNDAY WITH THE POSSIBLE EXCEPTION OF OCNL
MVFR CIGS AT KJST.
OUTLOOK...SUNDAY-WEDNESDAY
MON-TUE...MVFR WITH CHC -SHSN NW. VFR/NO SIG WX ELSEWHERE.
WED-THU...VFR/NO SIG WX.
&&
.CLIMATE...
ISSUED AT 148 AM EST SAT NOV 21 2015
WITH 10 DAYS LEFT IN THE MONTH...PRELIMINARY CLIMATE DATA
INDICATES THAT NOVEMBER 2015 IS CURRENTLY ON TRACK TO BE THE
WARMEST NOVEMBER ON RECORD AT OUR TWO LONG TERM CLIMATE SITES:
HARRISBURG AND WILLIAMSPORT. A CONTINUOUS WEATHER RECORD HAS BEEN
KEPT AT EACH SITE SINCE 1888 AND 1895 RESPECTIVELY.
THROUGH 11/20...
THE AVG. MONTHLY TEMPERATURE AT HARRISBURG IS 53.2 DEGREES OR
+7.2 DEGREES ABOVE NORMAL.
THE AVG. MONTHLY TEMPERATURE AT WILLIAMSPORT IS 50.9 DEGREES OR
+7.5 DEGREES ABOVE NORMAL.
THE TOP 5 WARMEST NOVEMBERS (CURRENT RANKINGS)
MDT: 2015 (53.2), 1931 (51.3), 1975 (50.0), 1999 (49.3), 1994
(49.0)
IPT: 2015 (50.9), 1931 (48.8), 1902 (47.3), 2009/1972 (47.2), 1913
(46.3)
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW WATCH FROM 1 AM EST SUNDAY THROUGH LATE
SUNDAY NIGHT FOR PAZ004.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...GRUMM/GARTNER
AVIATION...FITZGERALD/LA CORTE
CLIMATE...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
148 AM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL RAPIDLY MOVE OVER AND THEN EAST OF OUR AREA
OVERNIGHT AS A FAST WAVE AND COLD FRONT APPROACHES FROM THE WEST
SATURDAY AFTERNOON. THIS WILL TRIGGER RAIN TO SNOW SHOWERS
OVERNIGHT SATURDAY INTO SUNDAY AND POSSIBLE LAKE EFFECT SNOW IN
NORTHWEST PENNSYLVANIA SUNDAY INTO SUNDAY NIGHT. IT WILL BE A TAD
COLDER THEN NORMAL SUNDAY-MONDAY. A RIDGE WILL BUILD TO OVER THE
CENTRAL US TUESDAY INTO THANKSGIVING PROVIDING A RELATIVELY DRY
PERIOD AND WARMING TREND. DEEP SOUTHWESTERLY FLOW LATE NEXT WEEK
COULD BRING A CHANCE OF RAIN/RAIN SHOWERS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
03Z IR LOOP SHOWING MID/HIGH LVL CLOUDINESS MOVING INTO CENTRAL
PA...AS WAA ALOFT OVERSPREADS THE REGION AHEAD OF SHORTWAVE OVR
THE PLAINS STATES. LATEST NEAR TERM MDL DATA SUGGESTS THE CLOUD
COVER WILL BE THICKEST ARND 06Z...THEN THIN OUT AND PUSH NORTHEAST
OF THE AREA TOWARD DAWN. THE LGT WIND AND VERY DRY AIR ASSOC WITH
SFC HIGH PRES WILL ALLOW TEMPS TO FALL INTO THE 20S FOR MOST OF
THE AREA. LATEST HRRR TIMESERIES SHOW TEMPS BOTTOMING OUT ARND
04Z...RISING A BIT AS CLOUDS ARRIVE...THEN REACHING A SECOND MIN
AT DAWN.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
RIDGE OF HIGH PRES ALONG THE E COAST SHOULD ENSURE A DRY SATURDAY
ACROSS CENTRAL PA. LIGHT WINDS EXPECTED FOR MOST...ALTHOUGH THE
HIGHER ELEVATIONS OF THE ALLEGHENY HIGHLANDS WILL SEE SOME
INCREASING SOUTHEAST BREEZES IN THE AFTERNOON. BUFKIT SUPPORTS
AFTN GUSTS BTWN 20-25KTS.
LATEST MDL DATA INDICATES 8-7H BAROCLINIC ZONE AND ASSOC MID LVL
CLOUDINESS WILL SHIFT NORTH OF PA ON SATURDAY. WILL MAINTAIN MCLDY
SKIES FOR NOW ACROSS THE N MTNS. HOWEVER...MUCH OF CENTRAL PA
SHOULD EXPERIENCE A MSUNNY SATURDAY. ENS MEAN 925MB TEMPS NR 2C
SHOULD BE SUPPORTIVE OF MAX TEMPS BTWN 45-50F.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A FAST MOVING WAVE AND STRONG COLD FRONT WILL TRIGGER SOME LIGHT
RAIN WHICH WILL TURN TO SNOW QUICKLY IN THE NORTHWESTERN AREAS
SATURDAY NIGHT. FARTHER EAST VERY LIGHT RAIN LIKELY ENDING AS
SNOW SHOWERS OR FLURRIES SUNDAY. IT WILL TURN MARKEDLY COLDER
EARLY SUNDAY AND BREEZY.
THE COLD AIR...WARM LAKES AND WESTERLY WINDS INDICATE A POTENTIAL
ERIE SNOW BAND. AT THIS TIME SREF IS SUGGESTING 2-4 INCHES
POSSIBLE NEAR NY BORDER...BUT BEST SNOW IS LIKELY TO THE NORTH OF
THE PA/NY BORDER. WE WILL WAIT TO SEE 3KM NCAR ENSEMBLE TONIGHT
AND HOW IT FORECASTS THE SNOW. WE SHOWED GENERALLY 1-3 INCHES AT
THIS TIME IN THE LES EVENT AND WILL WAIT FOR HIGHER RESOLUTION
GUIDANCE.
SUNDAY WILL BE COLD AND BREEZY. THE COLD AIR SHOULD SLOWLY EASE ON
MONDAY INTO MONDAY NIGHT. WE BOTTOM OUT -1 TO -1.5SD BELOW NORMAL
FOR 850 MB TEMPS SUNDAY INTO MONDAY EVENING.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT...
ISSUED AT 120 AM EST SAT NOV 21 2015...
VFR WILL CONTINUE TODAY WITH SOME DETERIORATION IN FLYING
CONDITIONS EXPECTED LATER SATURDAY NIGHT INTO EARLY SUNDAY. SFC
WINDS FROM 100-150 DEGREES WILL INCREASE AS LOW PRESSURE
INTENSIFIES TRACKING ENEWD FROM THE LOWER OH VALLEY INTO THE LOWER
GREAT LAKES. ADDED LLWS TO THE WESTERN TAFS DUE TO 40-50KT
SOUTHERLY LOW LEVEL FLOW IN ADVANCE OF THE LOW AND TRAILING COLD
FRONT. RAIN SHOWERS SHOULD REACH THE WESTERN 1/3 OF THE AIRSPACE
BY 06Z SATURDAY AND EVENTUALLY TRANSITION TO -SHSN WITH IFR VIS
POSSIBLE AT BFD.
OUTLOOK...SUNDAY-WEDNESDAY
SUN...MVFR CIGS WEST TO VFR EAST. IFR VIS PSBL NW IN SHSN.
MON...MVFR/VFR CIGS WEST. VFR CENTRAL/EAST. NO SIG WX.
TUE...MVFR WITH CHC -SHSN NW. VFR/NO SIG WX ELSEWHERE.
WED...VFR/NO SIG WX.
&&
.CLIMATE...
ISSUED AT 148 AM EST SAT NOV 21 2015
WITH 10 DAYS LEFT IN THE MONTH...PRELIMINARY CLIMATE DATA
INDICATES THAT NOVEMBER 2015 IS CURRENTLY ON TRACK TO BE THE
WARMEST NOVEMBER ON RECORD AT OUR TWO LONG TERM CLIMATE SITES:
HARRISBURG AND WILLIAMSPORT. A CONTINUOUS WEATHER RECORD HAS BEEN
KEPT AT EACH SITE SINCE 1888 AND 1895 RESPECTIVELY.
THROUGH 11/20...
THE AVG. MONTHLY TEMPERATURE AT HARRISBURG IS 53.2 DEGREES OR
+7.2 DEGREES ABOVE NORMAL.
THE AVG. MONTHLY TEMPERATURE AT WILLIAMSPORT IS 50.9 DEGREES OR
+7.5 DEGREES ABOVE NORMAL.
THE TOP 5 WARMEST NOVEMBERS (CURRENT RANKINGS)
MDT: 2015 (53.2), 1931 (51.3), 1975 (50.0), 1999 (49.3), 1994
(49.0)
IPT: 2015 (50.9), 1931 (48.8), 1902 (47.3), 2009/1972 (47.2), 1913
(46.3)
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...GRUMM
AVIATION...STEINBUGL
CLIMATE...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
123 AM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL RAPIDLY MOVE OVER AND THEN EAST OF OUR AREA
OVERNIGHT AS A FAST WAVE AND COLD FRONT APPROACHES FROM THE WEST
SATURDAY AFTERNOON. THIS WILL TRIGGER RAIN TO SNOW SHOWERS
OVERNIGHT SATURDAY INTO SUNDAY AND POSSIBLE LAKE EFFECT SNOW IN
NORTHWEST PENNSYLVANIA SUNDAY INTO SUNDAY NIGHT. IT WILL BE A TAD
COLDER THEN NORMAL SUNDAY-MONDAY. A RIDGE WILL BUILD TO OVER THE
CENTRAL US TUESDAY INTO THANKSGIVING PROVIDING A RELATIVELY DRY
PERIOD AND WARMING TREND. DEEP SOUTHWESTERLY FLOW LATE NEXT WEEK
COULD BRING A CHANCE OF RAIN/RAIN SHOWERS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
03Z IR LOOP SHOWING MID/HIGH LVL CLOUDINESS MOVING INTO CENTRAL
PA...AS WAA ALOFT OVERSPREADS THE REGION AHEAD OF SHORTWAVE OVR
THE PLAINS STATES. LATEST NEAR TERM MDL DATA SUGGESTS THE CLOUD
COVER WILL BE THICKEST ARND 06Z...THEN THIN OUT AND PUSH NORTHEAST
OF THE AREA TOWARD DAWN. THE LGT WIND AND VERY DRY AIR ASSOC WITH
SFC HIGH PRES WILL ALLOW TEMPS TO FALL INTO THE 20S FOR MOST OF
THE AREA. LATEST HRRR TIMESERIES SHOW TEMPS BOTTOMING OUT ARND
04Z...RISING A BIT AS CLOUDS ARRIVE...THEN REACHING A SECOND MIN
AT DAWN.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
RIDGE OF HIGH PRES ALONG THE E COAST SHOULD ENSURE A DRY SATURDAY
ACROSS CENTRAL PA. LIGHT WINDS EXPECTED FOR MOST...ALTHOUGH THE
HIGHER ELEVATIONS OF THE ALLEGHENY HIGHLANDS WILL SEE SOME
INCREASING SOUTHEAST BREEZES IN THE AFTERNOON. BUFKIT SUPPORTS
AFTN GUSTS BTWN 20-25KTS.
LATEST MDL DATA INDICATES 8-7H BAROCLINIC ZONE AND ASSOC MID LVL
CLOUDINESS WILL SHIFT NORTH OF PA ON SATURDAY. WILL MAINTAIN MCLDY
SKIES FOR NOW ACROSS THE N MTNS. HOWEVER...MUCH OF CENTRAL PA
SHOULD EXPERIENCE A MSUNNY SATURDAY. ENS MEAN 925MB TEMPS NR 2C
SHOULD BE SUPPORTIVE OF MAX TEMPS BTWN 45-50F.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A FAST MOVING WAVE AND STRONG COLD FRONT WILL TRIGGER SOME LIGHT
RAIN WHICH WILL TURN TO SNOW QUICKLY IN THE NORTHWESTERN AREAS
SATURDAY NIGHT. FARTHER EAST VERY LIGHT RAIN LIKELY ENDING AS
SNOW SHOWERS OR FLURRIES SUNDAY. IT WILL TURN MARKEDLY COLDER
EARLY SUNDAY AND BREEZY.
THE COLD AIR...WARM LAKES AND WESTERLY WINDS INDICATE A POTENTIAL
ERIE SNOW BAND. AT THIS TIME SREF IS SUGGESTING 2-4 INCHES
POSSIBLE NEAR NY BORDER...BUT BEST SNOW IS LIKELY TO THE NORTH OF
THE PA/NY BORDER. WE WILL WAIT TO SEE 3KM NCAR ENSEMBLE TONIGHT
AND HOW IT FORECASTS THE SNOW. WE SHOWED GENERALLY 1-3 INCHES AT
THIS TIME IN THE LES EVENT AND WILL WAIT FOR HIGHER RESOLUTION
GUIDANCE.
SUNDAY WILL BE COLD AND BREEZY. THE COLD AIR SHOULD SLOWLY EASE ON
MONDAY INTO MONDAY NIGHT. WE BOTTOM OUT -1 TO -1.5SD BELOW NORMAL
FOR 850 MB TEMPS SUNDAY INTO MONDAY EVENING.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT...
ISSUED AT 120 AM EST SAT NOV 21 2015...
VFR WILL CONTINUE TODAY WITH SOME DETERIORATION IN FLYING
CONDITIONS EXPECTED LATER SATURDAY NIGHT INTO EARLY SUNDAY. SFC
WINDS FROM 100-150 DEGREES WILL INCREASE AS LOW PRESSURE
INTENSIFIES TRACKING ENEWD FROM THE LOWER OH VALLEY INTO THE LOWER
GREAT LAKES. ADDED LLWS TO THE WESTERN TAFS DUE TO 40-50KT
SOUTHERLY LOW LEVEL FLOW IN ADVANCE OF THE LOW AND TRAILING COLD
FRONT. RAIN SHOWERS SHOULD REACH THE WESTERN 1/3 OF THE AIRSPACE
BY 06Z SATURDAY AND EVENTUALLY TRANSITION TO -SHSN WITH IFR VIS
POSSIBLE AT BFD.
OUTLOOK...SUNDAY-WEDNESDAY
SUN...MVFR CIGS WEST TO VFR EAST. IFR VIS PSBL NW IN SHSN.
MON...MVFR/VFR CIGS WEST. VFR CENTRAL/EAST. NO SIG WX.
TUE...MVFR WITH CHC -SHSN NW. VFR/NO SIG WX ELSEWHERE.
WED...VFR/NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...GRUMM
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
302 AM EST SAT NOV 21 2015
.SHORT TERM (TODAY AND TONIGHT)...
TRANQUIL WEATHER CONDITIONS ACROSS THE AREA EARLY THIS MORNING.
CURRENT WATER VAPOR IMAGERY AND RAP UPPER AIR ANALYSIS INDICATES A
LARGE SCALE TROUGH ACROSS THE CENTRAL CONUS. AT THE SURFACE...HIGH
PRESSURE IS IN PLACE ACROSS THE MID-ATLANTIC WITH A SURFACE LOW
CURRENTLY ACROSS SOUTHERN MISSOURI WITH A COLD FRONT TRAILING INTO
THE SOUTHERN PLAINS. TEMPERATURES SHOULD WARM QUICKLY INTO THE MID
50S BY LATE THIS MORNING AS THE SURFACE LOW TRACKS TO THE NORTH OF
THE AREA THIS AFTERNOON. MOISTURE RETURN WITH THE SYSTEM WILL NOT
BE OVERLY IMPRESSIVE. IT WILL TAKE SOME TIME BEFORE LOW LEVEL WINDS
SWITCH AROUND TO THE SOUTH WITH THE SURFACE HIGH TO THE NORTHEAST.
THIS DELAY WILL CREATE A BRIEF AND NARROW WINDOW OF DEWPOINTS IN
THE 40S AND PW VALUES IN THE 0.75-0.85 INCH RANGE. THESE VALUES ARE
A BIT ABOVE NORMAL FOR THIS TIME OF YEAR...BUT AGAIN THIS MOISTURE
IS NOT EXPECTED TO LAST LONG. HAVE CONTINUED WITH THE HIGHEST POPS
AFTER 3PM WITH THE MOISTURE BEING LIMITED TO RIGHT ALONG THE
FRONTAL BOUNDARY. THE COLDEST AIR OF THE SEASON WILL MOVE IN BEHIND
THE FRONT LATE THIS EVENING INTO THE OVERNIGHT HOURS. ALL OF THE
MODELS INDICATE ENOUGH MOISTURE HANGING AROUND FOR A FEW LIGHT SNOW
SHOWERS/FLURRIES ACROSS THE HIGHER TERRAIN. AGAIN...MOISTURE IS
EXTREMELY LIMITED BUT THERE WILL BE SOME OROGRAPHIC LIFT WITH
LIMITED LOW LEVEL MOISTURE IN PLACE. IT APPEARS THE BEST TIME FOR
SNOW IN THE HIGH TERRAIN WILL BE FROM 06-12Z SUNDAY. THERE COULD
BE SOME MINOR ACCUMULATIONS OF UP TO HALF AN INCH IN THE HIGHEST
TERRAIN LATE TONIGHT INTO EARLY TOMORROW MORNING.
.LONG TERM (SUNDAY THROUGH FRIDAY)...
THE EXTENDED BEGINS WITH VERY COLD AIR MOVING INTO THE SOUTHERN
APPALACHIAN REGION. HIGHS ON SUNDAY WILL STRUGGLE TO REACH INTO THE
40S ACROSS THE TN VALLEY...WITH ONLY 30S OVER THE MOUNTAINS. COLD
AIR CONTINUES TO PUSH IN SUNDAY NIGHT WITH LOWS FALLING INTO THE
TEENS IN THE MOUNTAINS AND 20S ACROSS LOWER VALLEY LOCATIONS.
TEMPERATURES WILL SLOWLY BEGIN TO MODERATE ON MONDAY AS FLOW ALOFT
BEGINS LESS NORTHERLY. HOWEVER...THE WARMING TREND WILL BEGIN IN
EARNEST TUESDAY AND WEDNESDAY AS UPPER FLOW BECOME ZONAL. BY
THURSDAY AND FRIDAY...AN UPPER RIDGE BUILDS INTO THE REGION
ALLOWING DAYTIME HIGHS TO ONCE AGAIN REACH INTO THE 60S ACROSS MUCH
LOWER ELEVATIONS. OVERALL...WE WILL BE IN A QUIET WEATHER PATTERN
WITH DRY CONDITIONS EXPECTED THROUGHOUT THE EXTENDED. ONLY CONCERN
WILL BE AN APPROACHING WEATHER SYSTEM ON FRIDAY. CURRENT MODEL RUNS
BEGIN TO BRING MID AND HIGH CLOUDS IN BY FRIDAY BUT FOR NOW KEEP
ASSOCIATED PRECIP TO THE WEST UNTIL AFTER THE EXTENDED PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 59 33 46 27 / 20 20 0 0
KNOXVILLE MCGHEE TYSON AIRPORT, TN 60 33 43 23 / 20 40 10 0
OAK RIDGE, TN 60 33 42 23 / 30 30 0 0
TRI CITIES AIRPORT, TN 58 32 41 20 / 10 40 10 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
MA/MJB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1118 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 740 PM CST FRI NOV 20 2015
LOOKING A LOT MORE LIKE LATE NOVEMBER OUT THERE...AT LEAST FOR
PARTS OF THE AREA. NICE TO SEE THAT THIS STORM SYSTEM OVERALL IS
UNFOLDING AS EXPECTED THE PAST 24-36 HOURS...WITH INCOMING AMOUNTS
ACROSS MUCH OF THE CURRENT WARNING AREA MAINLY IN THE 4-7 INCH
RANGE SO FAR...HEAVIEST OF COURSE WHERE INDIVIDUAL STRONGER FGEN
BANDED ELEMENTS HAVE LAID OUT THE LONGEST...PRIMARILY SOUTH OF
HIGHWAY 18. FARTHER NORTH...AMOUNTS HAVE TAPERED CONSIDERABLY...
GENERALLY ONLY PUSHING AN INCH OR TWO ALONG THE IA/MN BORDER PER
REPORTS...AND ONLY A DUSTING TO PERHAPS A HALF INCH JUST SOUTH OF
THE I-90 CORRIDOR. THESE AMOUNTS ARE PRETTY MUCH IN LINE WITH
EARLIER THINKING..
DON`T PLAN ANY BIG CHANGES TO GOING HEADLINES...THOUGH MAY
ULTIMATELY HAVE TO DITCH THE WARNING FOR RICHLAND COUNTY PER RADAR
TRENDS...AS THE STRONGER FGEN BAND HAS REALLY WEAKENED OVER THAT
AREA THE PAST HOUR OR TWO. ALSO...WILL LIKELY NEED TO SPEED UP THE
EXIT TIME OF WIDESPREAD PRECIP PER RADAR TRENDS...THOUGH WITH THE
ARRIVAL OF THE ACTUAL UPPER WAVE...WE MAY TEND TO SEE SOME
REDEVELOPMENT WITHIN AN ELONGATING MID LEVEL DEFORMATION AXIS INTO
FAR SOUTHWEST WISCONSIN AND NORTHEAST IOWA. REGARDLESS OF THE
ACTUAL TIME...CURRENT HEADLINES DO COVER THE BIGGER ISSUE...WHICH
HAS BEEN IMPACT WITH QUITE A FEW REPORTS OF ACCIDENTS...CERTAINLY
NOT HELPED BY THE FACT THAT THIS IS THE FIRST EVENT OF THE SEASON.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 217 PM CST FRI NOV 20 2015
HAVE BEEN TRYING TO INTEGRATE CURRENT RADAR AND SURFACE
OBSERVATIONS INTO THE FORECAST TO FINE TUNE STORM. BOTTOM LINE IS
THE ADVISORIES AND WARNINGS LOOK ON TRACK FOR LOCATION. WE DID
UPDATE THE START TIME. HAVE LEFT THE END TIME ON SATURDAY AS THE
NORTHWEST WINDS OF 15 TO 25 MPH WILL CAUSE SOME DRIFTING...
ESPECIALLY ON THE HIGHER TERRAIN OF SWRN WI AND NERN IA.
CURRENT SNOW BAND IS IMPRESSIVE WITH AMOUNTS NEAR 15 INCHES NEAR
SIOUX FALLS SD TODAY AND MESSY ROADS EXTENDING NOW INTO PARTS OF
NERN IA UNDER THE SNOW BAND. GIVEN A MODERATE SNOW
RATE IN THE CENTRAL-EASTERN IA SNOW BAND...ACCUMULATING SNOW AND
SLICK ROADS HAPPEN FAIRLY QUICK AFTER ONSET. THIS BAND IS WELL
REPRESENTED BY 600-700 MB FRONTOGENESIS FORCING PER RAP ANALYSIS.
THE BAND SHOULD CONTINUE TO SHIFT NORTHEAST THROUGH EARLY EVENING. PER
VIGOROUS SHORTWAVE TROUGH IN KS/NEB MOVING AT US...THE
FRONTOGENESIS THEN REINVIGORATES A BIT LATER EVENING ON A NE-SW
ARC OVER THE SOUTHERN FORECAST AREA...WITH THE MAIN HEAVY SNOW
BAND NEAR HIGHWAY 20 TO I-80 WITH STRONGER FRONTOGENESIS INDICATED
IN THE SHORT TERM MODELS.
BIG PICTURE REMAINS THE SAME FOR THIS STORM. WE HAVEN`T CHANGED
THE TOTAL LIQUID FROM THIS STORM MUCH...BUT DO HAVE SOME CONCERNS
WITH SNOW RATIOS IN THE WARNING...ESPECIALLY CLOSER TO DUBUQUE AND
THE SOUTHERN HALF OF THE FAYETTE-CLAYTON-GRANT COUNTIES. THE
LATEST RAP AND 20.12Z NAM/GFS OUTPUT RUN THROUGH THE DENDRITIC
GROWTH ZONE COBB TECHNIQUE SUGGEST RATIOS COULD BE IN THE 20-24 TO
1 RANGE. WE HAVE INCREASED THOSE RATIOS TO 17 TO 1 ACROSS THE
WARNING WITH A 150-200 MB DENDRITE GROWTH ZONE SUGGESTED. THIS
RAISES TOTALS TOWARD A FOOT. WINDS WILL INCREASE ACROSS THE SOUTH
INTO THE 15 TO 25 MPH RANGE SATURDAY FOR A BIT OF DRIFTING SNOW.
MAIN MESSAGE IS THE SAME...WITH POSSIBLY A BIT MORE IMPACT ACROSS
THE FAR SOUTH /IA HIGHWAY 3/ WITH 10-12 INCHES AND SOME DRIFTING
SNOW. BELIEVE ACCUMULATING SNOW WILL REALLY BE SOUTH OF I-90...AND
THE HAZARDS LOOK LIKE THEY ARE PLACED WELL.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 217 PM CST FRI NOV 20 2015
NORTHWEST FLOW CONTINUES WITH A COLD WEEKEND. CONSENSUS
DETERMINISTIC MODEL RUNS FROM 20.12Z AGREED WELL ON A DYNAMIC
SYSTEM SHIFTING THROUGH NERN WI RAPIDLY SUNDAY NIGHT. THIS LOOKS
LIKE IT COULD SPREAD SOME SNOW ACROSS NORTHCENTRAL WI...LEAVING BY
MONDAY.
THE WEEK THEN BEGINS TO WARM AS ANOTHER LONGWAVE TROUGH DIGS IN
THE WEST. BY MID-WEEK PRECIPITATION WORKS INTO THE AREA ON A
MOIST FLOW. A CLOUDY PERIOD WITH POSSIBLY PRECIPITATION TYPE
ISSUES. AT THIS TIME IT APPEARS MAINLY LIKE A RAIN/SNOW SCENARIO
BUT DEPENDING ON HOW MOISTURE ARRIVES...SOME FREEZING DRIZZLE
COULD BE AROUND. THE MAIN IDEA NOW IS WARMING AND PRECIPITATION BY
MID-WEEK INTO THANKSGIVING. CONFIDENCE MODERATE WITH GOOD
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1118 PM CST FRI NOV 20 2015
SNOW WILL WIND DOWN FROM WEST TO EAST FOR BOTH KRST AND KLSE
THROUGH 07Z...LEAVING LINGERING MID CLOUDS FOR A TIME BEFORE
THINGS CLEAR BY SUNRISE. HOWEVER...THERE REMAINS CONSIDERABLE
QUESTIONS ABOUT JUST HOW MUCH ADDITIONAL STRATOCUMULUS WE MIGHT BE
ABLE TO MUSTER UP HEADING INTO MIDDAY AND THE AFTERNOON...WITH
QUITE CHILLY AIR ALOFT BUT DRYING DOWN LOW. UPSTREAM CLOUD TRENDS
ARE SOMEWHAT TELLING...WITH A STEADY SOUTHWARD EXPANSION OF LOWER
STRATUS. HOWEVER...ARRIVAL OF THAT STUFF DURING PEAK HEATING (SUCH
AS IT IS IN LATE NOVEMBER) DOES SUGGEST THINGS WILL REMAIN MORE
SCATTERED AT THIS TIME. DEFINITELY SOMETHING TO WATCH CLOSELY FOR
AVIATION INTERESTS...AS ANY CEILING TODAY WILL LIKELY BE MVFR.
OTHERWISE...A RETURN TO CLEAR SKIES IS EXPECTED TONIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR WIZ054-055-061.
WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR WIZ053.
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ094-095.
WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR MNZ096.
IA...WINTER STORM WARNING UNTIL 6 AM CST SATURDAY FOR IAZ008-009-018-
019.
WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR IAZ010-011-029-
030.
&&
$$
UPDATE...LAWRENCE
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...LAWRENCE
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1025 PM CST FRI NOV 20 2015
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 1006 PM CST FRI NOV 20 2015
LATEST TREND OF THE HRRR SUPPORTS THE 00Z NAM TO KEEP THE ACCUM
SNOW FURTHER SOUTH. WILL CANCEL THE ADVISORY.
UPDATE
ISSUED AT 915 PM CST FRI NOV 20 2015
TREND OF THE LAST FEW HOURS INDICATE A SOUTHERN SHIFT WITH THE
HEAVY SNOW BAND OVER SOUTHERN WISCONSIN. GRB SOUNDING THIS
EVENING SUGGESTS A LOT OF DRY AIR TO OVERCOME. BEST 850-700 FGEN
REGION WELL SOUTH. NORMALLY WOULD DROP THE ADVISORY WITH AMOUNTS
MINIMAL...BUT NEED TO CONSIDER THE FIRST SNOW OF THE SEASON.
THE 00Z NAM INDICATES A DIRECTION OF DROPPING THE ADVISORY...WILL
TRY TO TAKE A QUICK PEAK AT THE EARLY PART OF THE GFS THE NEXT
HOUR...AND GO FROM THERE. WE DO HAVE THE UPPER TROUGH DROPPING IN
TONIGHT INTO SATURDAY WHICH COULD PIVOT THE LIGHTER SNOW NORTH A
BIT...BUT THIS SYSTEM IS ALSO TRACKING A BIT FASTER.
&&
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 242 PM CST FRI NOV 20 2015
PRIMARY FOCUS TO BE ON THE SNOW POTENTIAL OVER SRN SECTIONS OF THE
FCST AREA LATE TNGT/SAT MORNING AS A SYSTEM PASSES BY TO OUR
SOUTH. MODEL INCONSISTENCY HAS BEEN A PROBLEM ALL WEEK...BUT IT
NOW APPEARS THAT THE 12Z RUN HAS AT LEAST TRIED TO ZERO ON A
TRACK/NRN EDGE OF SNOW. A SECONDARY FOCUS TO BE ON INCREASING LK
EFFECT FOR N-CNTRL WI AS WINDS GRADUALLY SHIFT TO THE NW AND COLD
AIR FLOWS OVER LK SUPERIOR.
THE 20Z MSAS SFC ANALYSIS SHOWED AN AREA OF HI PRES OVER THE OHIO
RIVER VALLEY WITH STRONG LOW PRES OVER HUDSON BAY AND WEAK LOW
PRES OVER THE CNTRL HI PLAINS. RADAR MOSAIC INDICATED A NARROW...
BUT INTENSE BAND OF SNOW OVER SE SD...NE NEBRASKA AND NRN IA.
SNOWFALL RATES WITHIN THIS INTENSE BAND WERE 2-3" PER HOUR!
EVEN AT THIS LATE DATE...THE NRN EDGE OF THE MAIN SNOW BAND WAS
NOT SET IN STONE AS THE MODELS CONTINUED TO TWEAK NORTH (NAM/GFS)
OR SOUTH (GEM). MODELS DO AGREE ON THE STRONG FRONTOGENETICAL
FORCING SIGNAL THAT RUNS FROM CNTRL IA E-NE INTO SRN WI/NRN IL
TNGT...THUS HIGHEST ACCUMULATION NUMBERS WL STAY TO OUR SOUTH.
HOWEVER...DO ANTICIPATE LIGHT ACCUMULATIONS (< 1") ALONG OUR SRN
TIER OF COUNTIES BY DAYBREAK. WE WL ALSO HAVE TO WATCH SFC WINDS
AS ANY SLIGHT VEERING TO THE NE COULD ADD TO ACCUMULATIONS OVER
MANITOWOC COUNTY.
LIGHT SNOW WL CONT OVER E-CNTRL WI THRU AT LEAST SAT MORNING AS
THE SFC LOW LIFTS NE FROM THE MID-MS VALLEY TOWARD THE ERN GREAT
LAKES AND MID-LEVEL FRONTOGENETICAL FORCING BEGINS TO SHIFT FROM
SE WI INTO LWR MI. AN ADDITIONAL INCH OR TWO OF ACCUMULATION IS
POSSIBLE OVER E-CNTRL WI...THUS PLAN ON ISSUING A WINTER WEATHER
ADVY FOR WINNEBAGO...CALUMET AND MANITOWOC COUNTIES FROM 03Z-21Z
SAT (PRIMARILY FOR SRN SECTIONS OF THESE COUNTIES). TRAILING THIS
SYSTEM IS A SHRTWV TROF THAT IS FCST TO SWEEP INTO THE WRN GREAT
LAKES ON SAT. WHILE THE BULK OF THE SYNOPTIC MOISTURE TO BE TIED
UP WITH THE INITIAL STORM...WINDS ARE EXPECTED TO TURN NW AND
INTRODUCE LK EFFECT SNOW SHWRS TO N-CNTRL WI. THERE IS A POTENTIAL
FOR AN INCH OR TWO OF ACCUMULATION...ESPECIALLY OVER THE SNOWBELT
REGION OF VILAS CNTY. MAX TEMPS TO ONLY BE IN THE MID TO UPR 20S
N-CNTRL...TO THE MID 30S E-CNTRL WI. ADD IN A NW WIND AT 10 TO 20
MPH AND WIND CHILL VALUES WL ONLY BE IN THE UPR TEENS TO LWR 20S.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 242 PM CST FRI NOV 20 2015
SEVERAL CONCERNS TO DEAL WITH INCLUDE LAKE EFFECT SNOW SHOWERS
ACROSS THE NORTH SATURDAY NIGHT INTO SUNDAY MORNING...A CLIPPER
SYSTEM SUNDAY NIGHT INTO MONDAY MORNING AND THEN ABOVE NORMAL
TEMPERATURES AND UNSETTLED WEATHER FOR THANKSGIVING DAY AND
BLACK FRIDAY.
PERUSAL OF THE BUFKIT SOUNDING OVER WESTERN LAKE SUPERIOR
SATURDAY NIGHT PRETTY IMPRESSIVE SATURDAY NIGHT. ABUNDANT
MOISTURE UP TO TEN THOUSAND FEET...EQL LEVELS OF TWELVE TO
FIFTEEN THOUSAND FEET AND LAKE TO 850MB TEMPERATURE DIFFERENCES
APPROACHING 20C. LOW LEVEL WINDS ARE NOT AS FAVORABLE...BUT
CLOSE ENOUGH TO WARRANT INCREASING SNOWFALL TOTALS FROM PREVIOUS
FORECAST. CONTEMPLATED LAKE EFFECT SNOW WATCH THINKING THE SNOW
BELT REGION OF VILAS COUNTY COULD SEE OVER 6 INCHES IN A FEW SPOTS
IF BANDS SET UP. PER COORDINATION WITH DULUTH AND MARQUETTE...WILL
HOLD OFF FOR NOW AND MIDNIGHT SHIFT MAY GO WITH AN ADVISORY.
A CLIPPER SYSTEM WILL MOVE ACROSS THE REGION SUNDAY NIGHT...BRINGING
A CHANCE OF LIGHT SNOW ACROSS THE SOUTH AND LIGHT SNOW LIKELY ACROSS
THE NORTH. AN INCH OR TWO IS EXPECTED ACROSS THE NORTH WITH LIGHTER
AMOUNTS TO THE SOUTH.
ATTENTION THEN TURNS TO WEDNESDAY THROUGH FRIDAY WITH AN UNSETTLED
PERIOD EXPECTED. PRECIPITATION SHOULD BE MAINLY RAIN ACROSS
CENTRAL AND NORTHEAST WISCONSIN...WITH MORE OF A MIX OF RAIN AND
SNOW ACROSS NORTH-CENTRAL WISCONSIN. LATEST ECMWF HAS PUSHED THE
FRONT FURTHER SOUTH ON FRIDAY WHERE THE NORTH MAY BE DRY. PLENTY
OF TIME TO WORK OUT THE DETAILS. BELOW NORMAL TEMPERATURES THIS
WEEKEND SHOULD RETURN TO OR ABOVE NORMAL BY THE MIDDLE OF NEXT
WEEK.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1025 PM CST FRI NOV 20 2015
VFR CIGS EXPECTED OVER MOST AREAS TONIGHT INTO SATURDAY.
EXCEPTIONS INCLUDE LOCALIZED MVFR CIGS WITH LIGHT SNOW MAINLY
SOUTH OF HIGHWAY 10 INCLUDING THE ATW AND MTW TAFS OVERNIGHT INTO
SATURDAY. ANOTHER EXCEPTION FOR PATCHY MVFR CIGS AND VSBYS INCLUDE
NORTH CENTRAL WISCONSIN LATE TONIGHT INTO SATURDAY NIGHT WITH
INCLUDES THE RHI TAF.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........TDH
SHORT TERM.....KALLAS
LONG TERM......ECKBERG
AVIATION.......TDH
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
1006 PM CST FRI NOV 20 2015
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 1006 PM CST FRI NOV 20 2015
LATEST TREND OF THE HRRR SUPPORTS THE 00Z NAM TO KEEP THE ACCUM
SNOW FURTHER SOUTH. WILL CANCEL THE ADVISORY.
UPDATE
ISSUED AT 915 PM CST FRI NOV 20 2015
TREND OF THE LAST FEW HOURS INDICATE A SOUTHERN SHIFT WITH THE
HEAVY SNOW BAND OVER SOUTHERN WISCONSIN. GRB SOUNDING THIS
EVENING SUGGESTS A LOT OF DRY AIR TO OVERCOME. BEST 850-700 FGEN
REGION WELL SOUTH. NORMALLY WOULD DROP THE ADVISORY WITH AMOUNTS
MINIMAL...BUT NEED TO CONSIDER THE FIRST SNOW OF THE SEASON.
THE 00Z NAM INDICATES A DIRECTION OF DROPPING THE ADVISORY...WILL
TRY TO TAKE A QUICK PEAK AT THE EARLY PART OF THE GFS THE NEXT
HOUR...AND GO FROM THERE. WE DO HAVE THE UPPER TROUGH DROPPING IN
TONIGHT INTO SATURDAY WHICH COULD PIVOT THE LIGHTER SNOW NORTH A
BIT...BUT THIS SYSTEM IS ALSO TRACKING A BIT FASTER.
&&
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 242 PM CST FRI NOV 20 2015
PRIMARY FOCUS TO BE ON THE SNOW POTENTIAL OVER SRN SECTIONS OF THE
FCST AREA LATE TNGT/SAT MORNING AS A SYSTEM PASSES BY TO OUR
SOUTH. MODEL INCONSISTENCY HAS BEEN A PROBLEM ALL WEEK...BUT IT
NOW APPEARS THAT THE 12Z RUN HAS AT LEAST TRIED TO ZERO ON A
TRACK/NRN EDGE OF SNOW. A SECONDARY FOCUS TO BE ON INCREASING LK
EFFECT FOR N-CNTRL WI AS WINDS GRADUALLY SHIFT TO THE NW AND COLD
AIR FLOWS OVER LK SUPERIOR.
THE 20Z MSAS SFC ANALYSIS SHOWED AN AREA OF HI PRES OVER THE OHIO
RIVER VALLEY WITH STRONG LOW PRES OVER HUDSON BAY AND WEAK LOW
PRES OVER THE CNTRL HI PLAINS. RADAR MOSAIC INDICATED A NARROW...
BUT INTENSE BAND OF SNOW OVER SE SD...NE NEBRASKA AND NRN IA.
SNOWFALL RATES WITHIN THIS INTENSE BAND WERE 2-3" PER HOUR!
EVEN AT THIS LATE DATE...THE NRN EDGE OF THE MAIN SNOW BAND WAS
NOT SET IN STONE AS THE MODELS CONTINUED TO TWEAK NORTH (NAM/GFS)
OR SOUTH (GEM). MODELS DO AGREE ON THE STRONG FRONTOGENETICAL
FORCING SIGNAL THAT RUNS FROM CNTRL IA E-NE INTO SRN WI/NRN IL
TNGT...THUS HIGHEST ACCUMULATION NUMBERS WL STAY TO OUR SOUTH.
HOWEVER...DO ANTICIPATE LIGHT ACCUMULATIONS (< 1") ALONG OUR SRN
TIER OF COUNTIES BY DAYBREAK. WE WL ALSO HAVE TO WATCH SFC WINDS
AS ANY SLIGHT VEERING TO THE NE COULD ADD TO ACCUMULATIONS OVER
MANITOWOC COUNTY.
LIGHT SNOW WL CONT OVER E-CNTRL WI THRU AT LEAST SAT MORNING AS
THE SFC LOW LIFTS NE FROM THE MID-MS VALLEY TOWARD THE ERN GREAT
LAKES AND MID-LEVEL FRONTOGENETICAL FORCING BEGINS TO SHIFT FROM
SE WI INTO LWR MI. AN ADDITIONAL INCH OR TWO OF ACCUMULATION IS
POSSIBLE OVER E-CNTRL WI...THUS PLAN ON ISSUING A WINTER WEATHER
ADVY FOR WINNEBAGO...CALUMET AND MANITOWOC COUNTIES FROM 03Z-21Z
SAT (PRIMARILY FOR SRN SECTIONS OF THESE COUNTIES). TRAILING THIS
SYSTEM IS A SHRTWV TROF THAT IS FCST TO SWEEP INTO THE WRN GREAT
LAKES ON SAT. WHILE THE BULK OF THE SYNOPTIC MOISTURE TO BE TIED
UP WITH THE INITIAL STORM...WINDS ARE EXPECTED TO TURN NW AND
INTRODUCE LK EFFECT SNOW SHWRS TO N-CNTRL WI. THERE IS A POTENTIAL
FOR AN INCH OR TWO OF ACCUMULATION...ESPECIALLY OVER THE SNOWBELT
REGION OF VILAS CNTY. MAX TEMPS TO ONLY BE IN THE MID TO UPR 20S
N-CNTRL...TO THE MID 30S E-CNTRL WI. ADD IN A NW WIND AT 10 TO 20
MPH AND WIND CHILL VALUES WL ONLY BE IN THE UPR TEENS TO LWR 20S.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 242 PM CST FRI NOV 20 2015
SEVERAL CONCERNS TO DEAL WITH INCLUDE LAKE EFFECT SNOW SHOWERS
ACROSS THE NORTH SATURDAY NIGHT INTO SUNDAY MORNING...A CLIPPER
SYSTEM SUNDAY NIGHT INTO MONDAY MORNING AND THEN ABOVE NORMAL
TEMPERATURES AND UNSETTLED WEATHER FOR THANKSGIVING DAY AND
BLACK FRIDAY.
PERUSAL OF THE BUFKIT SOUNDING OVER WESTERN LAKE SUPERIOR
SATURDAY NIGHT PRETTY IMPRESSIVE SATURDAY NIGHT. ABUNDANT
MOISTURE UP TO TEN THOUSAND FEET...EQL LEVELS OF TWELVE TO
FIFTEEN THOUSAND FEET AND LAKE TO 850MB TEMPERATURE DIFFERENCES
APPROACHING 20C. LOW LEVEL WINDS ARE NOT AS FAVORABLE...BUT
CLOSE ENOUGH TO WARRANT INCREASING SNOWFALL TOTALS FROM PREVIOUS
FORECAST. CONTEMPLATED LAKE EFFECT SNOW WATCH THINKING THE SNOW
BELT REGION OF VILAS COUNTY COULD SEE OVER 6 INCHES IN A FEW SPOTS
IF BANDS SET UP. PER COORDINATION WITH DULUTH AND MARQUETTE...WILL
HOLD OFF FOR NOW AND MIDNIGHT SHIFT MAY GO WITH AN ADVISORY.
A CLIPPER SYSTEM WILL MOVE ACROSS THE REGION SUNDAY NIGHT...BRINGING
A CHANCE OF LIGHT SNOW ACROSS THE SOUTH AND LIGHT SNOW LIKELY ACROSS
THE NORTH. AN INCH OR TWO IS EXPECTED ACROSS THE NORTH WITH LIGHTER
AMOUNTS TO THE SOUTH.
ATTENTION THEN TURNS TO WEDNESDAY THROUGH FRIDAY WITH AN UNSETTLED
PERIOD EXPECTED. PRECIPITATION SHOULD BE MAINLY RAIN ACROSS
CENTRAL AND NORTHEAST WISCONSIN...WITH MORE OF A MIX OF RAIN AND
SNOW ACROSS NORTH-CENTRAL WISCONSIN. LATEST ECMWF HAS PUSHED THE
FRONT FURTHER SOUTH ON FRIDAY WHERE THE NORTH MAY BE DRY. PLENTY
OF TIME TO WORK OUT THE DETAILS. BELOW NORMAL TEMPERATURES THIS
WEEKEND SHOULD RETURN TO OR ABOVE NORMAL BY THE MIDDLE OF NEXT
WEEK.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 517 PM CST FRI NOV 20 2015
VFR CIGS EXPECTED OVER MOST AREAS TONIGHT. THE ONLY EXCEPTION
WOULD BE FOR A WEST TO EAST MVFR OR LOWER END VFR CIG DEVELOPING
SOUTH OF HIGHWAY 29 TONIGHT AS A STORM SYSTEM TRACKS OVER NORTHERN
ILLINOIS. CONDITIONS WILL DETERIORATE FURTHER SOUTH OVER SOUTHERN
WISCONSIN. AS THIS SYSTEM DEPARTS SATURDAY MORNING CONDITIONS
EXPECTED TO IMPROVE. HOWEVER PATCHY MVFR CIGS OVER NORTHERN
WISCONSIN LATE TONIGHT MAY BECOME MORE WIDESPREAD ON SATURDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 3 PM CST SATURDAY FOR WIZ048>050.
&&
$$
UPDATE.........TDH
SHORT TERM.....KALLAS
LONG TERM......ECKBERG
AVIATION.......TDH
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
250 AM CST MON NOV 23 2015
...Updated Short and Long Term Discussion...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 248 AM CST MON NOV 23 2015
A northwesterly flow across the Central Rockies will become more
westerly during the day. This improving westerly flow will result
in a developing trough of low pressure along the lee of the
Rockies and some warming in the 950mb to 850mb level. Based on the
weak net 24 hour warming trend in the 950mb to 850mb level along
with the mixing potential and 00z Tuesday temperatures at this
height the highs today are expected to 3-5F warmer than yesterday.
Tonight the surface winds will be a little stronger than the past
few nights. This combined with increasing low level moisture will
tend towards staying close to the latest MET/MAV guidance.
.LONG TERM...(Tuesday THROUGH Sunday)
ISSUED AT 248 AM CST MON NOV 23 2015
Models remain in good agreement with an upper level storm system
moving from the coast of British Columbia into the western United
States during the first half of the work week. This will result in
the westerly flow across the Central Rockies early in the week
backing to the Southwest by early Wednesday. Subtle upper waves
embedded in this developing southwesterly flow still evident based
on 500mb to 400mb potential vorticity. One of which will be
crossing western Kansas on Wednesday and then a stronger wave on
Thursday. A cold front moving south across the Northern Plains on
Tuesday will extend from eastern Colorado into north central
Kansas by early Wednesday. Ahead of this surface boundary a
southerly flow will continue to draw more humid air northward into
central and portions of western Kansas. Early morning stratus and
fog appears possible south of this front based on model soundings.
At this time the depth of the low level moisture does not appear
deep enough to support drizzle but later shifts may wish to
reevaluate this. By Wednesday evening warm air advection will
begin to improve across western Kansas. Given this lift along
increasing moisture will keep the chance for rain showers and even
a few thunderstorms developing Wednesday night, especially east of
highway 283.
Chance for precipitation will continue on Thursday with the
precipitation type being mainly in the form of liquid early in the
the day as the cold front moves across southwest Kansas. During
the afternoon the colder air moving into western Kansas behind the
cold front will cool that atmosphere enough for the rain to change
over to snow from northwest to southeast. BUFR soundings even
suggest there may be a brief period of freezing rain or sleet
before the change over to snow. Given how far out this event is
will keep precipitation type simple at this time.
On Thursday night the ongoing precipitation will continue early
and then begin to taper off from north to south as a 700mb
baroclinic zone moves across western Kansas. At this time it
appears that the prevailing precipitation type will be snow with
the possible exception of portions of south central Kansas. Upper
level jet dynamics shift north and northeast early and isentropic
downglide observed in the I285 to I295 level by 06z Friday.
Frontogenesis also not that strong near the 700mb baroclinic zone.
The better moisture and lift appears to be focused above the 700mb
level so can not rule out some light snow but accumulations should
be light. Possible exception will be near the OK border,
especially in far southwest Kansas, where up to an inch may not be
completely out of the question.
On Friday any lingering light snow will end, however Friday still
appears to be cloudy and cold as a surface ridge axis begins to
build into western Kansas. Based on 950mb and 850mb temperatures
at 18z Friday and 00z Saturday the previous forecast with highs
only in the 30s still look on track.
On Friday night and Saturday moisture and isentropic lift begins
to improve across western Kansas in the i285 to i300 levels as the
cold dome of high pressure begins to build into western Kansas and
the next upper level wave begins to approach the area from the
southwest. Over parts of western Kansas a southeast upslope flow
is also evident west of the surface ridge axis. Given moisture
return and lift late Friday night into Saturday there will be
improving chances for snow across all of western Kansas early this
weekend. This chance for precipitation will continue through early
Sunday. Some snow accumulations will be possible from this weekend
event, however at how much snow and where is still unclear.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Monday NIGHT)
ISSUED AT 1145 PM CST SUN NOV 22 2015
VFR conditions are expected overnight and Monday based on BUFR
soundings moisture profiles along with the latest RUC and HRRR.
The winds will be west to southwest at less than 10 knots.
Southwesterly winds on Monday are expected to increase to around
15 knots by the early afternoon as a the weak surface trough axis,
located across eastern Colorado, remains nearly stationary and
deepens.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 34 60 38 / 0 0 0 0
GCK 63 28 59 31 / 0 0 0 0
EHA 63 31 66 37 / 0 0 0 0
LBL 64 32 63 35 / 0 0 0 0
HYS 62 33 57 37 / 0 0 0 0
P28 64 35 61 47 / 0 0 0 0
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...Burgert
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
1147 PM CST SUN NOV 22 2015
...Updated Synopsis and Aviation discussions...
.SYNOPSIS...
ISSUED AT 1145 PM CST SUN NOV 22 2015
At 00z Monday a 500mb trough extended from the Upper Great Lakes
to the Tennessee Valley. A 500mb ridge axis was located along the
western United states. Over the Central United States a northwest
flow was evident at the 700mb and 500mb level. Across Kansas and
Nebraska earlier this evening 850mb temperatures varied from +3 at
Topeka to +8C at Dodge City and North Platte.
&&
.SHORT TERM...(THIS EVENING THROUGH Monday)
ISSUED AT 316 PM CST SUN NOV 22 2015
Northwest flow aloft will persist through the next couple of days.
Weak westerly surface flow will give way to south winds once again
on Monday as the surface trough develops over eastern Colorado. As
more broad zonal flow develops by Monday night, an initial lead
westerly shortwave will be approaching the region. Models suggest
this will be mainly a dry/ non-precipitation events, with probably
an increase in cloud cover heading into the Tuesday period.
Continually but slightly increasing high temperatures are likely in
the meantime as the boundary layer temperatures rise sue to
adiabatically warmed air from the higher terrain. The snow over
extreme western Hamilton county will likely be eliminated, and highs
could reach the low 60s area wide on Monday. The latest ECMWF model
temperatures have appear to do the best in the medium range and were
generally followed.
.LONG TERM...(Monday NIGHT THROUGH Sunday)
ISSUED AT 316 PM CST SUN NOV 22 2015
The more amplified wave will be on the heels right around the
Thanksgiving travel period. Initially higher surface winds will
likely mean slower warming Tuesday and perhaps slightly cooler
highs. An increase in cirrus clouds should occur by late Tuesday
with the aforementioned shortwave before stronger surface pressure
falls develop ahead of the strong cold front all the models show
by Thanksgiving day. The main problem will be precipitation, how
much and what type. Rain and thunderstorms are possible in the
prefrontal environment as the models indicate modest moisture
transport, but it is possible most of this will be well to the
east in eastern Kansas as well. It is possible our far western
Kansas counties will be on the low end for precipitation
probabilities, but fare better after the frontal passage for
ra/sn. The models indicate another system on its heels by around
saturday, and precipitation probabilities remain in the forecast
through the rest of the extended.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Monday NIGHT)
ISSUED AT 1145 PM CST SUN NOV 22 2015
VFR conditions are expected overnight and Monday based on BUFR
soundings moisture profiles along with the latest RUC and HRRR.
The winds will be west to southwest at less than 10 knots.
Southwesterly winds on Monday are expected to increase to around
15 knots by the early afternoon as a the weak surface trough axis,
located across eastern Colorado, remains nearly stationary and
deepens.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 29 61 33 59 / 0 0 0 0
GCK 26 59 28 56 / 0 0 0 0
EHA 26 60 33 62 / 0 0 0 0
LBL 27 61 32 59 / 0 0 0 0
HYS 28 60 31 55 / 0 0 0 0
P28 30 61 34 59 / 0 0 0 0
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SYNOPSIS...Burgert
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1246 AM EST MON NOV 23 2015
.SYNOPSIS...
LOW PRESSURE WILL DEVELOP ALONG A STATIONARY FRONT EAST OF THE
REGION TONIGHT AND MOVE NORTHEAST MONDAY TOWARD NOVA SCOTIA. HIGH
PRESSURE WILL BUILD TOWARD THE REGION MON NIGHT INTO TUE.
&&
.NEAR TERM /THROUGH TODAY/...
UPDATE 1240 AM: HAVE ADJUSTED TEMPERATURE... DEWPOINT AND WIND. NO
OTHER CHANGES.
SFC LOW CURRENTLY SITTING OFF OF THE VIRGINIA CAPES AND RIDING UP
ALONG FRONTAL BOUNDARY JUST OFFSHORE. FAIRLY TIGHT GRADIENT EXISTS
BTWN PCPN AND NO PCPN AS EXPECTED WITH HUL HVG RAIN AND PQI
NOTHING IN THE WAY OF PCPN. RADAR POPUP SKEW T IS SHOWING HUL
ISOTHERMAL FROM ABOUT 900MB UP WITH BLYR ABV ZERO ALL THE WAY BACK
TO ALLAGASH. THIS AGREES WELL WITH LATEST HRRR DATA THUS HV
ADJUSTED WX GRIDS BASED ON HRRR FCST DATA THRU THE MRNG.
EXPECT THAT PCPN WL BE HIT AND MISS IN NATURE FROM ABOUT PQI
NORTHWARD BUT IF IT CAN GET THIS AFTN NORTH IT SHOULD NOT BEGIN TO
MIX WITH SNOW UNTIL CLOSE TO 03Z. PCPN SHUD GRADUALLY SPREAD NORTH
AFT ABOUT 05Z AS LOW TRACKS CLOSER TO GULF OF MAINE IN COMBINATION
WITH RFQ OF H3 SPEED MAX GETTING EVER CLOSER TO CWA. THIS WL
BRING THE BEST CHC FOR ACCUMULATING SNOW FOR NORTHERN AREAS BFR
DAYBREAK.
AT THIS TIME IT APPEARS THAT QPF AMNTS WL BE LIGHT FOR NRN ZONES
AND WL BE HARD-PRESSED TO SEE MORE THAN AN INCH OF SNOW AND SLEET
FOR AREAS NORTH OF A MILLINOCKET TO HOULTON LINE. THUS WL CONTINUE
WITH MENTION OF AMNTS UP TO AN INCH BY MRNG. FURTHER TO THE SOUTH
HV LOWERED STORM TOTAL SNOW AMNTS BY ARND AN INCH AS IT APPEARS
THAT CLD AIR WL TAKE LONGER TO WRAP IN BHND LOW ESPECIALLY ALONG
THE COAST. HWVR, WL CONT WITH WINTER WX ADVISORY AS STILL
EXPECTING WIDESPREAD 1-4 INCHES ON TOP OF SLEET THAT FALLS. ALL
THIS WL FALL ON ALREADY WET ROADWAYS WHICH WL QUICKLY ICE OVER AS
TEMPS FALL DRG THE DAY TOMORROW. HIGHEST SNOW TOTALS LOOK TO OCCUR
ACRS NRN WASHINGTON CNTY AS WELL AS PARTS OF SE AROOSTOOK CNTY.
PREV DISCUSSION BLO...
LONGER RANGE MODELS HAVE COME INTO BETTER CONSENSUS FOR THIS
AFTN`S FCST UPDATE REGARDING THE COASTAL LOW EVENT MOVG NE FROM
OFF THE MID ATLC STATES TNGT TOWARD THE CNTRL NOVA SCOTIA MON
AFTN. THE 12Z DTMNSTC ECMWF BACKED OFF FROM BEING FURTHER N LIKE
THE PRIOR 00Z ECMWF RUN...BOTH WITH THE PSN OF THE SFC LOW AND
HEAVIER QPF FURTHER N INTO CNTRL AND NRN PTNS OF THE FA. THE
FURTHER SE TRACK OF THE 12Z GFS AND CANGEM MODELS SEEMS TO BE
INITIALLY VERIFYING BASED ON THE TRAJECTORIES OF THE WRN EDGE
OF RADAR REF MOVG INTO THE MID COAST AND DOWNEAST PTNS OF ME LATE
THIS AFTN.
BASED ON THE CURRENT FCST OF THE LOW TRACK...MILD AIR CURRENTLY
OVR THE FA WILL BE REPLACED BY SIG COLDER AIR MOVG E FROM QB AS
THE LOW HELPS ADVECT IT SE INTO OUR FA LATER TNGT INTO MON MORN.
TEMPS WILL FALL FAIRLY QUICKLY...FIRST ACROSS THE NW HLF LATER
THIS EVE THEN SPREADING SE THRU THE REST OF THE FA LATE TNGT INTO
MON MORN...RESULTING IN PRECIP CHGNG FROM RN TO SN NW TO SE ACROSS
THE FA DURG THIS TM...PERHAPS ACCOMPANIED BY A BRIE PD OF SLEET
BASED ON SREF PRECIP TYPES AND FCST SOUNDINGS. THE TRICKY PART OF
THIS FCST WILL BE OVR E CNTRL AND DOWNEAST PTNS OF THE FA WHERE
SIG PRECIP RATES MAY STILL BE GOING ON WHEN TEMPS APCH OR FALL
BELOW FZG...MEANING LCTNS CHGNG TO SNOW LATEST TNGT N OF THE
IMMEDIATE DOWNEAST COAST COULD RECEIVE THE MOST SN DUE TO GREATER
REMAINING QPF LEFT WITH THIS EVENT. SPEAKING OF QPF... STORM TOTAL
QPF WILL RANGE FROM NEAR ZERO OVR THE FAR NW TO NEARLY 2.00 INCHES
OVR THE EXTREME SE. FOR NOW...OUR OFFICIAL MAX SNFL TOTALS ARE 3
TO 5 INCHES OVR NRN AND CNTRL WASHINGTON COUNTIES WITH LESSER
AMOUNTS ELSEWHERE...BUT GIVEN UNCERTAINTIES OF CHGOVR TM AND
POTENTIAL INTENSITY OF SNFL AFT THE CHGOVR...CONFIDENCE WITH MAX
AMOUNTS OVR THIS PTN OF THE FA IS NOT HIGH WITH SIG MORE OR LESS
POSSIBLE. LATER SHIFTS WILL NEED TO MONITOR OBSVD AND MODEL TRENDS
WITH THIS EVENT.
IN ANY EVENT...SN WILL TAPER TO SCT SN SHWRS N AND RN/SN SHWRS
CNTRL AND DOWNEAST MON AFTN AND THEN END BY LATE IN THE DAY. BOTH
LOWS TNGT AND HI TEMPS MON WILL BE COLDER...SPCLY OVR CNTRL AND
DOWNEAST PTNS OF THE FA.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
THE SHORT TERM WILL FEATURE FAIR WEATHER UNDER A BUILDING RIDGE,
THOUGH AT LEAST TUE WILL BE A BIT COOLER THAN NORMAL. AT THE
BEGINNING OF THE SHORT TERM, THE BULK OF THE PRECIP IS EXPECTED TO
HAVE DEPARTED TO THE EAST. HOWEVER, WITH THE BASE OF THE UPR TROF
SWINGING OVER THE AREA MON NIGHT, CAN`T RULE OUT SOME LINGERING
CLOUDS AND A FEW LIGHT SN SHWRS IN THE FAR NRN CWA, AS WAS
REFLECTED IN A FEW MODELS.
BEYOND THAT, HIGH PRESSURE AND RIDGING TUE THRU WED WILL BRING
PARTLY TO MOSTLY SUNNY SKIES TO THE STATE. COLD AIR DRAWN IN
BEHIND THE LOW MON NIGHT AND GOOD RADIATIONAL COOLING WILL SET
THE STAGE FOR SOME OF THE COLDEST TEMPS IN THE CWA THUS FAR THIS
COLD SEASON MON AND TUE NIGHTS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL GRADUALLY SLIDE OFF THE EAST COAST THURSDAY,
KEEPING CONDITIONS DRY FOR THANKSGIVING DAY. THIS WILL ALSO PLACE
THE REGION UNDER SOUTHWEST FLOW ON THE BACKSIDE OF THE HIGH,
ALLOWING TEMPERATURES TO WARM INTO THE MID AND UPPER 40S. HOWEVER,
LOW PRESSURE MOVING BY TO OUR NORTH WILL SLOWLY DRAG A COLD FRONT
EASTWARD ACROSS THE EASTERN US/CANADA THURSDAY NIGHT THROUGH
FRIDAY. THERE`S SOME DISAGREEMENT AMONGST THE LONGER-RANGE MODELS
ON THE EXACT TIMING OF THIS FRONT AND ITS PRECIPITATION, BUT THE
HIGHEST THREAT FOR FRONTAL PASSAGE LOOKS TO OCCUR SOMETIME LATE
FRIDAY THROUGH SATURDAY. IF THE FRONT HOLDS OFF UNTIL FRIDAY
NIGHT, EXPECT WE`LL SEE VERY MILD TEMPERATURES FOR THE DAY AFTER
THANKSGIVING AS HIGHS TOP OUT IN THE UPPER 40S TO LOWER 50S.
HOWEVER, IF THE FRONT MOVES THROUGH A LITTLE FASTER (SIMILAR TO
THE GFS SOLUTION), NORTHERN MAINE MAY HAVE A COOLER AND WETTER
FRIDAY THAN IS CURRENTLY IN THE FORECAST. REGARDLESS, EXPECT MUCH
COLDER AIR WILL MOVE IN BEHIND THE FRONT. SUNDAY LOOKS TO BE THE
COLDEST DAY OF THE WEEKEND AT THE MOMENT, WITH HIGHS ONLY IN THE
20S IN THE NORTH, AND LOWS IN THE TEENS.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
NEAR TERM: IFR EXPECTED NEXT 24 HOURS AT MOST TERMINALS IN
RAIN/SNOW. EXCEPTION WILL BE FVE WHERE SITE WILL MOST LIKELY BE
AFFECTED BY IFR CIGS WITH PCPN REMAINING TO THE SOUTH. STILL SOME
QUESTION AS TO HOW MUCH CAR AND PQI WILL SEE WITH REGARD TO PTYPE
AS THEY WILL BE ON NORTHERN EDGE OF PCPN SHIELD. HUL WILL SEE
RA/SN MIX AROUND 03Z THEN OVER TO ALL SNOW AFTER 06Z. BGR CAN BE
EXPECTED TO BE RA/SN AFTER 04Z THEN SWITCHING TO SNOW BY 08Z. BHB
WILL BE LATEST TO SEE CHANGEOVER TO RA/SN BY 09Z AND ALL SNOW
AROUND 10Z. BY 18Z MON BHB, BGR AND HUL WILL SEE IMPROVEMENT TO
VFR CIGS WITH FVE, CAR AND PQI VFR BY 15Z. NW WINDS WILL BE GUSTY
DURING THE DAY AT 15G25KTS.
SHORT TERM: ASIDE FROM THE CHC FOR SOME MVFR CIGS AND ISO SN
SHWRS FOR KFVE BEFORE 09ZTUE, ALL TERMINALS ARE EXPECTED TO HAVE
VFR CIGS AND VIS THROUGH WED EVENING. VFR CONDITIONS WILL THEN
CONTINUE THROUGH FRIDAY, THOUGH MVFR CEILINGS WILL BE POSSIBLE AT
THE NORTHERN TERMINALS FRIDAY AFTERNOON AS A COLD FRONT APPROACHES
FROM THE NORTH.
&&
.MARINE...
NEAR TERM: E TO NE WINDS WILL INCREASE TO SCA CRITERIA FOR THE
INNER BAY/HARBOR MZ THIS EVE AND GALES (IN GUSTS) OVR THE OUTER
MZS LATE TNGT...BACKING TO THE N AS THEY CONTINUE INTO MON. GALES
OVR THE OUTER MZS WILL NEED TO BE TRANSITIONED TO AN SCA LATER MON
AFTN. KEPT CLOSE TO WW3 WV GUIDANCE FOR FCST WV HTS.
SHORT TERM: SCA WIND GUSTS AND SEAS LKLY ONGOING OFFSHORE AT THE
START OF THE SHORT TERM. WILL CONTINUE TUE AM BEFORE GRADUALLY
DIMINISHING TUE PM AS HIGH PRES BUILDS INTO THE AREA.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
MEZ006-011-015.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MEZ016-017-029-030-032.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR ANZ052.
SMALL CRAFT ADVISORY UNTIL 3 AM EST EARLY THIS MORNING FOR
ANZ050-051.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR ANZ050-051.
&&
$$
NEAR TERM...MIGNONE
AREA FORECAST DISCUSSION
NWS GRAY ME
1239 AM EST MON NOV 23 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE NORTHEASTWARD THROUGH THE GULF OF MAINE
TONIGHT ALLOWING FOR SOME RAIN AND SNOW ON THE COASTAL PLAIN. HIGH
PRESSURE WILL BEGIN TO BUILD INTO THE REGION MONDAY MORNING WHILE
LOW PRESSURE TRACKS TO OUR EAST. THE HIGH WILL SHIFT OFFSHORE ON
WEDNESDAY AND A BROAD UPPER LEVEL RIDGE BUILDS OVER NEW ENGLAND.
THIS WILL BRING ABOVE AVERAGE TEMPERATURES THROUGH THE END OF THE
WORK WEEK. HIGH PRESSURE WILL HOLD OFFSHORE THROUGH FRIDAY AND THE
NEXT CHANCE FOR RAIN WILL COME OVER THE WEEKEND POSSIBLY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPDATE...
COLD AIR CONTINUES TO ADVECT SOUTH AND EASTWARD OVERNIGHT WHILE
HEIGHTS LOWER ALOFT. THIS WILL CONTINUE TO ALLOW THE RA TO CHANGE
TO SN OVERNIGHT. MODERATE SNOW AS FAR SOUTH AS THE GYX OFFICE AS
OF MIDNIGHT ACCORDING TO SOCIAL MEDIA AND TELCON REPORTS.
LATEST HRRR RUN CONTINUES TO SHOW A NICE BAND SETTING UP FROM
COASTAL CUMBERLAND COUNTY AND POINTS NORTHEASTWARD THROUGH THE I95
CORRIDOR AND POINTS TO THE EAST AT 09Z. BEST FOCUS SHIFTS EAST
INTO THE KNOW/WALDO COUNTY AREAS BY 12Z. SOME OF THE FIRST
ACCUMULATING SNOWS OF THE SEASON WILL BE OCCURRING DURING THAT
TIME PERIOD...LEADING TO HAZARDOUS TRAVEL CONDITIONS.
PREV DISC...
11 PM UPDATE: RADAR SHOWS RAIN SHIELD MOVING INTO
COASTAL AND MIDCOAST AREAS AS FORECAST. QUICK PEEK AT LATEST
MODELS SHOW GOOD CONTINUITY FROM PRIOR RUN. COLD AIR WORKING IN
INTO THE LOWER LEVELS OVER THE NEXT SEVERAL HOURS WILL GRADUALLY
CHANGE PTYPE TO SNOW. ONLY MINOR TWEAKS TO TEMPS OTRW NO CHANGES
NEEDED ATTM.
630 PM UPDATE: UPDATED TEMPS BASED ON LATEST OBS DATA. ALSO ADDED
SOME AREAS OF FOG FOR COASTAL AND THE ADJACENT AREAS OF ME/NH FOR
NEXT FEW HOURS BEFORE WINDS WINDS AND INCREASING MIXING IN THOSE
AREAS INCREASE.
PREVIOUS DISCUSSION:
CHALLENGING FORECAST THIS SUNDAY AFTERNOON AS WE/LL BE DEALING
WITH A TIGHT PRECIPITATION GRADIENT OVERNIGHT. A SOUTHERN STREAM
SHORT WAVE TROUGH CURRENTLY EJECTING OFF THE CAROLINA COAST THIS
EVENING WILL MOVE NORTHEAST OVERNIGHT. THIS TROUGH AND ASSOCIATED
SFC LOW PRESSURE WILL COME CLOSE ENOUGH TO THE NEW ENGLAND COAST
TO ALLOW FOR THE SHIELD OF PRECIPITATION TO MOVE INTO THE COASTAL
PLAIN OF MAINE AND NEW HAMPSHIRE. HOWEVER...THE QUESTION IS HOW
FAR WEST...HOW MUCH QPF...AND HOW MUCH WILL FALL AS SNOW?
THE 12Z MODELS AND ENSEMBLES HAVE COME MORE OR LESS INTO GENERAL
AGREEMENT WITH THE WESTERN EXTENT OF THE STRONG FORCING FOR
ASCENT. HOWEVER...SHARP BACK EDGES ARE ALWAYS TRICKY SINCE 5 TO
10 MILES COULD MEAN THE DIFFERENCE BETWEEN NO PRECIPITATION AND UP
TO A HALF INCH LIQUID OR LIQUID EQUIVALENT. USED A CONSENSUS
APPROACH FOR THE OVERNIGHT HOURS...AND GAVE THE LATEST MESOSCALE
MODELS /HRRR AND RAP/ A LITTLE MORE CREDENCE IN THE BLEND. THIS
WAS ALSO THE CASE WITH TIMING OF POPS AS WELL.
AT THE SAME TIME...THE COLUMN AS A WHOLE WILL GRADUALLY GET
COLDER OVERNIGHT...AND THIS INCLUDES A CONTRIBUTION FROM DYNAMIC
COOLING THAT SHOULD OCCUR ONCE THE HEAVIER PRECIPITATION GETS
GOING. SO BLENDING THE ABOVE IDEAS WITH TEMPERATURE AND POP
TRENDS ALONG WITH A CONSENSUS-BASED QPF FORECAST...IT LOOKS AS
THOUGH SOME ACCUMULATING SNOW IS IN THE CARDS TONIGHT FOR THE
COASTAL PLAIN AS WELL AS PORTIONS OF CENTRAL MAINE.
RAIN THIS EVENING SHOULD GRADUALLY FLIP OVER TO WET SNOW AFTER
MIDNIGHT FROM WEST TO EAST AS A COLUMN COOLS. THEREAFTER...IT
DEPENDS ON HOW HARD IT IS PRECIPITATING THAT WILL DETERMINE HOW
MUCH SNOW STICKS. USING OUR CURRENT IDEAS...WE ARE FORECASTING UP
TO AN INCH OF SNOW ON THE MAINE COASTAL PLAIN...WITH 1 TO 3 INCHES
ON THE MID COAST NORTHWARD INTO PARTS OF CENTRAL MAINE. HIGHER
ELEVATIONS NEAR THE MID COAST SUCH AS THE CAMDEN HILLS NORTHWARD
TO THE HILLY SPOTS IN WALDO COUNTY NEAR ROUTES 202 AND 139 COULD
ALSO EXPERIENCE HIGHER AMOUNTS. PERHAPS UP TO 4 INCHES DEPENDING
HOW FAST THE PRECIP CHANGES OVER AND HOW HARD IT FALLS. AT THIS
TIME...SNOW AMOUNTS SHOULD BE MINIMAL ENOUGH TO AVOID WIDESPREAD
POWER OUTAGE PROBLEMS. HOWEVER...ISOLATED OUTAGES WILL BE
POSSIBLE GIVEN THE EXPECTED HEAVY AND WET NATURE TO THE SNOW AFTER
THE CHANGEOVER COMBINED WITH INCREASING NORTHERLY WINDS.
OTHERWISE...FURTHER SOUTH DOWN I-95 INTO
AUGUSTA...LEWISTON...GRAY...AND PORTLAND...UP TO AN INCH WILL BE
POSSIBLE /PERHAPS A LITTLE BIT MORE IN AUGUSTA/WATERVILLE
CORRIDOR/. TEMPERATURES WILL FALL TO NEAR FREEZING IN THESE AREAS
TOWARD MORNING SO IT/S POSSIBLE ANY WET SNOW AND STANDING WATER
COULD FREEZE AND THIS MAY ALLOW FOR SOME SLIPPERY SPOTS FOR THE AM
COMMUTE. IF THE IMPACTS LOOK TO BE A LITTLE MORE SUBSTANTIAL LATER
ON...AN ADVISORY MAY BE ISSUE FURTHER SOUTH. FOR NOW...WE HAVE A
WINTER WEATHER ADVISORY FOR JUST WALDO AND KNOX COUNTY WHERE THE
POTENTIAL FOR ACCUMULATING SNOW IS GREATEST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
ANY SNOW WILL MOVE OUT EARLY MONDAY MORNING...WITH SUNNY SKIES
QUICKLY MOVING IN. OVERALL...COLD TEMPERATURES AND BLUSTERY WINDS
WILL BE THE RULE MONDAY. HIGH PRESSURE MOVES IN MONDAY NIGHT ALLOW
FOR A COLD AND CLEAR NIGHT.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THE MODELS ARE IN GENERAL AGREEMENT ON THE LONG WAVE PATTERN
THROUGH LATE NEXT WEEK. THE UPPER TROUGH ACROSS THE REGION AT THE
START OF THE PERIOD WILL LIFT OUT INTO THE MARITIMES BY
WEDNESDAY...REPLACED BY A BROAD RIDGE AND WEST-SOUTHWEST FLOW
ALOFT...IN RESPONSE TO DIGGING PACIFIC SHORTWAVE ENERGY CARVING
OUT A DEEP TROUGH OVER THE WESTERN CONUS. BY FRIDAY...SIGNIFICANT
DIFFERENCES EMERGE IN NUMERICALS WITH GFS MOST PROGRESSIVE WITH
HANDLING OF WESTERN TROUGH...WITH SLOWER ECMWF/CMC-GLOBAL
SCENARIO REMAINING THE PREFERRED SOLUTION FOR NOW.
IN THE DAILIES...A FEW CLOUDS TUESDAY AS THE UPPER TROUGH SWINGS
ACROSS THE AREA. RISING HEIGHTS WITH HIGH PRESSURE AND DRY AIR
BRINGS MODERATING TEMPERATURES FOR WEDNESDAY AND THURSDAY. THE
PREFERRED AND SLOWER ECMWF/CMC-GLOBAL SOLUTIONS KEEP THE RIDGE
ACROSS THE AREA AND THE APPROACHING FRONTAL SYSTEM WELL TO OUR
WEST ON FRIDAY. THE COLD FRONT SHOULD CROSS THE AREA ON SATURDAY...WITH
SHARPLY COLDER TEMPERATURES AND SOME UPSLOPE SNOW SHOWERS IN ITS
WAKE TO ROUND OUT NEXT WEEKEND.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MVFR TO IFR CONDITIONS ARE PROBABLE TONIGHT ON THE
COASTAL PLAIN WHERE RAIN CHANGING TO SNOW IS LIKELY. VFR
CONDITIONS RESUME MONDAY MORNING AND CONTINUE THROUGH MONDAY
NIGHT. GUSTY NORTHWESTERLY WINDS TO 25 KT WILL BE LIKELY LATE
TONIGHT AND MONDAY.
LONG TERM...
NO SIGNIFICANT OPERATIONAL IMPACTS DUE TO WEATHER EXPECTED.
&&
.MARINE...
SHORT TERM...SMALL CRAFT ADVISORIES HAVE BEEN HOISTED FOR TONIGHT
THROUGH MONDAY. NOT OUT OF THE QUESTION THESE WILL NEED TO BE
UPGRADED TO GALES FOR A TIME LATE TONIGHT INTO MONDAY. WINDS AND
SEAS DIMINISH MONDAY NIGHT.
LONG TERM...
THU - FRI...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE WITH GUSTS
TO NEAR GALE OUTSIDE THE BAYS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 8 AM EST THIS MORNING FOR MEZ022-
027-028.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EST TUESDAY FOR ANZ150>154.
&&
$$
JC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
450 AM EST MON NOV 23 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 450 AM EST MON NOV 23 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A TROF EXTENDING S THRU
THE GREAT LAKES REGION. SHEARED OUT SHORTWAVE/LEFT EXIT OF 120+KT
UPPER JET EXTENDING FROM SASKATCHEWAN INTO THE UPPER MISSISSIPPI
VALLEY HAS GENERATED SOME AREAS OF -SN INTO WRN UPPER MI OVERNIGHT.
MODELS OVER THE LAST DAY OF RUNS CORRECTLY TRENDED LIGHTER WITH THIS
PCPN AS SNOW THAT HAS OCCURRED HAS BEEN VERY LIGHT WITH NOT MUCH
MORE THAN A DUSTING OF ACCUMULATION WHERE SNOW HAS FALLEN PER
WEBCAMS. TO THE E...JUST AS SOME HIGH RES MODELS WERE INDICATING 24
HRS AGO...THE REGIONAL CANADIAN IN PARTICULAR...A BURST OF HVY SNOW
MOVED N OFF NRN LAKE MI INTO PARTS OF THE ERN U.P. OVER THE LAST
SEVERAL HRS. IT APPEARS THE EXTREME SE CORNER OF LUCE COUNTY
PROBABLY SAW A VERY BRIEF PERIOD OF MDT TO HVY SNOW AROUND 06Z. THAT
AREA OF MDT/HVY SNOW HAS SHIFTED E INTO THE STRAITS VCNTY SINCE
THEN.
THERE IS STILL SOME CONCERN FOR LAKE ENHANCED SNOW OFF NRN LAKE MI
TO SHIFT/REFORM BACK TO THE W TODAY. ON THE HIGH EXTREME IS THE
REGIONAL CANADIAN WHICH GENERATES 0.3 INCHES OF QPF IN THE FAR SE
CORNER OF LUCE COUNTY BTWN 15Z AND 00Z. SINCE THE MAJORITY OF AVBL
HIGH RES GUIDANCE...INCLUDING THE HIGH RES CANADIAN...KEEPS THE BULK
OF REDEVELOPING LAKE ENHANCED SNOW JUST E OF LUCE COUNTY...WILL KEEP
SNOW AMOUNTS UNDER ADVY CRITERIA WITH PERHAPS 1.5-2 INCHES TO THE SE
OF KERY. ELSEWHERE....PATCHY -SN MOVING ACROSS WRN UPPER MI ATTM
SHOULD DISSIPATE OVER THE NEXT SEVERAL HRS AS IT SHIFTS E AND HAS TO
OVERCOME INITIAL DRY LOWER LEVEL AIR. THEN...A SFC LOW PRES TROF
WILL SWING INTO WRN UPPER MI LATE MORNING/AFTN...BRINGING A WIND
SHIFT TO THE W TO NW. EXPECT -SHSN TO ACCOMPANY THE TROF AS OVERLAKE
INSTABILITY WITH 850MB TEMPS AROUND -7C WILL BE MORE THAN SUFFICIENT
TO GENERATE -SHSN ALONG THE TROF/CONVERGENCE ZONE AS IT CROSSES WRN
LAKE SUPERIOR. THIS WILL THEN TRANSITION TO SCT LAKE EFFECT
-SHSN INTO TONIGHT FOR AREAS FAVORED BY NW WINDS AS 850MB TEMPS DROP
A DEGREE OR TWO C. INITIALLY...INVERSION IS UP AROUND 7KFT THIS
EVENING...BUT FALLS TO AROUND 4KFT W OVERNIGHT AND TO AROUND 5KFT E
LATE. DESPITE THE DECENTLY HIGH INVERSION HEIGHTS...SNOW
ACCUMULATIONS WILL BE LIMITED DUE TO THE DGZ BEING ABOVE THE
CONVECTIVE LAYER. AT THIS POINT...EXPECT ACCUMULATIONS MOSTLY UNDER
1 INCH...BUT IF ANY RELATIVELY STATIONARY BANDS SET UP...THERE
CERTAINLY COULD BE ISOLATED 2-3 INCH AMOUNTS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 422 AM EST MON NOV 23 2015
...RAIN CHANGING TO SNOW WED NIGHT INTO THANKSGIVING DAY WITH
ACCUMULATING SNOW POSSIBLE INTO THU NIGHT...
IN LARGER SCALE...DEEP TROUGH OVER EASTERN CONUS SLIDES TO EASTERN
CANADA ON TUE WHILE SPLIT FLOW TROUGHING DEVELOPS WESTERN CANADA TO
WESTERN CONUS. 1000-850MB TROUGH FORMING ON TUE OVER ROCKIES AND
ADJACENT PLAINS AND LOW-LEVEL HIGH PRESSURE SETTLING TO SOUTHEAST
CONUS WILL ALLOW S/SE WINDS AT SFC TO BRING INCREASING MOISTURE OFF
THE GULF OF MEXICO TOWARD THE MIDDLE MISSISSIPPI RIVER VALLEY. WILL
STAY DRY OVER UPR LAKES ON TUE BUT LATE TUE NIGHT INTO WED MORNING
SOUNDINGS SHOW INCREASING MOISTURE BLO H9 INTO UPPER GREAT LAKES.
IF THERE IS ANY PRECIP AROUND ON WED MORNING...IT LIKELY WOULD TAKE
FORM OF DZ/FZDZ DEPENDING ON SFC TEMPS. BEST CHANCE FOR LIGHT ICING
WOULD BE OVER INTERIOR CNTRL CWA FM IRON/DICKINSON INTO BARAGA AND
WESTERN MARQUETTE COUNTY. MODELS SOMETIMES ARE TOO OVERDONE ON THIS
TYPE OF LOW-LEVEL MOISTENING BUT IN THIS CASE THERE IS DECENT SNOW
PACK JUST TO THE SOUTH SO THAT MAY HELP THE EXPANSION OF LOW-LEVEL
MOISTURE.
LATER ON WEDNESDAY DEEPER MOISTURE AND LARGER SCALE FORCING INCREASE
STEADILY AHEAD OF SHORTWAVE TROUGH SLIDING OVER MANTIOBA AND
NORTHERN ONTARIO. LOW-LEVEL THETA-E ADVECTION INCREASES BRIEFLY
BEFORE BEING SHUNTED TO THE SOUTH AND EAST ON WED NIGHT. SHOULD SEE
LIGHT RAIN BECOME MORE WIDESPREAD...BUT WITHOUT MUCH OF STRONG
MOISTURE TAP AHEAD OF THE TROUGH WITH THE NORTHERN STREAM SHORTWAVE
TROUGH...RAINFALL AMOUNTS SHOULD BE LIGHT. COOLER AIR WITH H85 TEMPS
DOWN BLO -2C SLIDES IN AFTER MIDNIGHT WED NIGHT OVER THE WEST AND
THAT SHOULD TURN ANY LINGERING RAIN TO SNOW. GFS SOUNDINGS AND H85-
H7 RH FIELDS FM THE ECMWF INDICATE MID-LEVEL DRYING MAY LEAD TO
CHANCES OF FREEZING DRIZZLE OR DRIZZLE INSTEAD OF SNOW LATE WED
NIGHT INTO THANKSGIVING MORNING WITH MOIST LAYER AT TEMPS BLO 0C BUT
MUCH WARMER THAN -10C. UPSLOPE FLOW OFF LK SUPERIOR WOULD ALSO AID
IN LOW-LEVEL LIFT AND MAYBE LEAD TO GREATER CHANCES OF DRIZZLE FOR
WEST AND NCNTRL UPR MICHIGAN. ADDED MENTION OF DZ/FZDZ IN THE GRIDS
FOR THESE AREAS.
ATTN LATER ON THANKSGIVING TURNS TO WAVE OF LOW PRESSURE THAT RIDES
NORTHEAST ALONG THE TROUGH OVER THE UPR GREAT LAKES. 00Z ECMWF
TRENDED FARTHER WEST WITH THE WAVE WHILE THE GFS TRENDED FARTHER
EAST. IF THE ECMWF IS CORRECT SWATH OF MODERATE PRECIP WOULD LIFT
BACK OVER AT LEAST THE SOUTH AND EAST CWA THANKSGIVING AFTN INTO
THU NIGHT. SINCE THE INITIAL TROUGH/COLD FRONT IS THROUGH MOST CWA
PTYPE WOULD MOSTLY BE SNOW...EXCEPT OVER FAR SCNTRL WHERE WARM AIR
LINGERS AS EVEN ECMWF SHOWS H85 TEMPS AT LEAST +1C WHEN HEAVIER QPF
IS FORECAST TO MOVE THROUGH. SFC TEMPS STILL MID 30S AS WELL SO NO
RISK OF ANY FREEZING PRECIP EITHER. JUST INLAND OVER SOUTH CENTRAL
AND OVER MOST OF THE EASTERN CWA /N WINDS LEADING TO OFFSHORE WINDS
AT ESC AND ISQ/ COULD SEE SEVERAL INCHES OF WET SNOW WITH THE ECMWF
SOLN AS 12 HR QPF BTWN 18Z THU AND 06Z FRI IS AT LEAST 0.5 IF NOT UP
TO 0.75 INCH. MEANWHILE...LATEST GFS BARELY IS OVER 0.25 INCHES FOR
THAT TIME FRAME. GEM IS MORE LIKE THE ECMWF WITH TOTAL QPF...BUT MUCH
WARMER AND WOULD RESULT IN MOSTLY RAIN FOR THOSE AREAS. WPC PREFERRED
CONSENSUS OF GFS/ECMWF/GEM. WILL CONTINUE TO MENTION THE RAIN TO SNOW
AND SOME ACCUMULATING SNOW IN THE HWO...BUT CANNOT PLAY UP THE SNOW
TOO MUCH OR GET TOO SPECIFIC YET GIVEN THE UNCERTAINTIES THAT REMAIN.
BEHIND THIS SYSTEM...TURNS COLD ENOUGH FOR LAKE EFFECT SNOW SHOWERS
OFF LK SUPERIOR FRI INTO FRI NIGHT. ON FRI...AREAS FAVORED BY N
WINDS MAY SEE SOME SNOW FOR A CHANGE...THEN WOULD BE MAINLY NW FLOW
AREAS FRI NIGHT. DRY LOW-LEVEL AIRMASS WITH STRONG HIGH BUILDING IN
SHOULD LIMIT EXTENT OF LES. BASED ON CURRENT MODEL SOLUTIONS IT IS
DOUBTFUL AMOUNTS WOULD REACH ADVY LEVELS FRI-FRI NIGHT. SLIGHT
WARMING TREND WITH GENERALLY DRY WEATHER IS EXPECTED FOR NEXT
WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1225 AM EST MON NOV 23 2015
A DISTURBANCE MOVING THROUGH THE REGION WILL BRING LIGHT SNOW INTO
THE WEST HALF OF UPPER MI. THIS SHOULD GRADUALLY DROP CONDITIONS
INTO THE MVFR RANGE LATE IN THE NIGHT. EVEN THOUGH ANY SNOW TODAY
WILL BE LIGHT...MVFR CONDITIONS WILL PERSIST AS LOW LEVEL MOISTURE
LINGERS ACROSS THE REGION. HOWEVER...WNW WINDS WITH MORE OF A
DOWNSLOPE COMPONENT WILL FAVOR VFR CIGS AT KSAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 AM EST MON NOV 23 2015
NO GALES ARE EXPECTED ON LAKE SUPERIOR THRU THE END OF THE WEEK.
PREVIOUSLY...THERE WERE INDICATIONS OF A GALE EVENT THU NIGHT/FRI
AFTER A COLD FRONT PASSES. HOWEVER...IT NOW APPEARS THAT THE FRONT
WILL BE WEAKER SO THAT WINDS WILL REMAIN BLO GALE FORCE. LIGHTEST
WINDS THIS WEEK WILL OCCUR TUE AS A HIGH PRES RIDGE QUICKLY SHIFTS
ACROSS THE UPPER GREAT LAKES. STRONGEST WINDS THIS WEEK WILL OCCUR
LATE TUE NIGHT/WED OVER THE E HALF OF LAKE SUPERIOR IN THE SOUTHERLY
FLOW AHEAD OF THE AFOREMENTIONED COLD FRONT AND THEN LATE THU/FRI
AFTER THE FRONT PASSES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
207 AM EST MON NOV 23 2015
.SYNOPSIS...
A HIGH AMPLITUDE UPPER TROUGH EXTENDING FROM CENTRAL CANADA TO
THE EASTERN U.S. WILL BRING MAINLY DRY CONDITIONS AND BELOW
NORMAL TEMPERATURES THROUGH TUESDAY. A GRADUAL WARMUP AND
CONTINUED DRY WEATHER WILL FOLLOW FOR WEDNESDAY THROUGH FRIDAY AS
A LARGE AREA OF HIGH PRESSURE DRIFTS EAST AND OFF THE MID ATLANTIC
SEABOARD. A COLD FRONT WILL MOVE SOUTHEAST ACROSS THE STATE LATE
FRIDAY INTO SATURDAY WITH THE NEXT CHANCE OF RAIN
SHOWERS...CHANGING TO SCATTERED SNOW SHOWERS ON SATURDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
A LOW PWAT AIR MASS...RELATIVELY LOW SUBSIDENCE INVERSION HGTS OF
JUST 4-5 KFT AGL OR SO...AND LIMITED MFLUX OFF OF LK ERIE FROM
CROSS LAKE/NWRLY FLOW WILL LEAD TO CLOUDS AND THE LIKELIHOOD OF
MAINLY LIGHT SNOW SHOWERS ACROSS WARREN AND MCKEAN COUNTIES EARLY
TODAY... WHILE SKIES ACROSS MUCH OF THE REST OF THE REGION WILL
BE CLEAR TO PARTLY CLOUDY.
05Z HRRR SHOWS ALMOST NO MEASURABLE SNOW FALLING FROM THE
GENERALLY SHALLOW STRATO CU DECK ACROSS THE NW MTNS...THOUGH SFC
OBS BENEATH THIS CLOUD SHIELD /SUCH AS KELZ/ SUGGESTS THAT
ADDITIONAL LIGHT ACCUMS OF SNOW /ANOTHER COATING TO 1.5 INCHES/
COULD OCCUR THIS MORNING INVOF KBFD AND AREAS TO THE WEST ACROSS
WARREN COUNTY.
LOW TEMPS EARLY THIS MONDAY SHOULD DIP INTO THE UPPER TEENS
ACROSS SOME NORTHERN AND WESTERN MTN LOCATIONS...WITH THE REST OF
THE REGION SEEING MINS IN THE 20S.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
A WEAK CLIPPER WILL MOVE QUICKLY SE FROM THE UPPER GLAKES THIS
AFTERNOON INTO TUESDAY. WAA AHEAD OF THIS SYSTEM COULD PRODUCE A
BIT OF LGT SNOW/FLURRIES THIS EVENING...MAINLY OVR THE NW MTNS.
BLEND OF LATEST MDL OUTPUT SUPPORTS NOTHING MORE THAN A FRESH
DUSTING OVER THE NW COUNTIES.
HIGH TEMPS THIS AFTERNOON WILL RANGE FROM NEAR 32F OVR THE HIGHER
TERRAIN OF NRN AND WRN PENN...TO THE LOWER 40S ACROSS THE
SOUTHEAST PART OF OUR CWA.
IN GENERAL...WINDS SHOULD BE FAIRLY LIGHT BENEATH SFC RIDGE AS IT
SLIDES EAST ACROSS PENN TODAY. HOWEVER...BUFKIT SUGGESTS SW WINDS
COULD GUST AS HIGH AS 20KTS ACROSS THE W MTNS LATE TODAY...AS
THE LLVL P-GRADIENT TIGHTENS BETWEEN WEAK LOW PRESSURE OVR THE
GRT LKS...AND HIGH PRES OVR THE SOUTHERN STATES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
A MODERATION OF TEMPERATURES WILL BE STARTING NEAR THE BEGINNING
OF THE LONG TERM PERIOD AS UPPER PATTERN TRANSITIONS TOWARD MORE
ZONAL FLOW EARLY IN THE WEEK...THEN SOUTHWESTERLY FLOW IN RISING
HEIGHTS IN RESPONSE TO A DIGGING UPPER TROF OVER THE WESTERN U.S.
INTERMOUNTAIN REGION.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT
ISSUED AT 134 AM EST MON NOV 23 2015
IR SATELLITE LOOP SHOWS AREA OF MVFR TO LOW VFR CIGS COVERING THE
NW 1/3 OF THE AIRSPACE PUSHING SOUTHEAST APPROACHING FIG/UNV/IPT.
LIGHT SNOW SHOWERS/FLURRIES MAY ALSO EXPAND ACROSS THIS AREA BUT
ISOLD VIS RESTRICTIONS SHOULD BE LIMITED TO MVFR. EXPECT LINGERING
SNOW TO DIMINISH BY THE AFTERNOON WITH MAINLY VFR CONDITIONS. SFC
WINDS 8-10KTS FROM 280-320 DEGREES THROUGH THE AFTERNOON /GUSTS
15-20KTS AT MDT-LNS/ WILL DECREASE AND BACK TO 200-250 DEGREES BY
TONIGHT. VFR SHOULD PREVAIL AT MOST SITES OVERNIGHT BUT MVFR CIGS
COULD RETURN TO THE NW AIRSPACE BY EARLY TUESDAY MORNING.
OUTLOOK...TUESDAY-FRIDAY
TUE...MVFR CIGS AND SCATTERED SNOW SHOWERS PSBL NW.
WED...VFR/NO SIG WX EXPECTED.
THU...LOW CIGS PSBL/NO SIG WX EXPECTED.
FRI...VFR/MVFR WITH RAIN SHOWERS PSBL MAINLY FRIDAY NIGHT.
&&
.CLIMATE...
UPDATED AT 210 AM EST MON NOV 23 2015
WITH 8 DAYS LEFT IN THE MONTH...PRELIMINARY CLIMATE DATA
INDICATES THAT NOVEMBER 2015 CURRENTLY RANKS AS THE WARMEST
NOVEMBER ON RECORD AT OUR TWO LONG TERM CLIMATE SITES: HARRISBURG
AND WILLIAMSPORT. A CONTINUOUS WEATHER RECORD HAS BEEN KEPT AT
EACH SITE SINCE 1888 AND 1895 RESPECTIVELY.
THROUGH 11/22...
THE AVG. MONTHLY TEMPERATURE AT HARRISBURG IS 52.2 DEGREES OR
+6.6 DEGREES ABOVE NORMAL.
THE AVG. MONTHLY TEMPERATURE AT WILLIAMSPORT IS 50.0 DEGREES OR
+6.9 DEGREES ABOVE NORMAL.
THE TOP 5 WARMEST NOVEMBERS (8 DAYS LEFT FOR 2015)
MDT: 2015 (52.2), 1931 (51.3), 1975 (50.0), 1999 (49.3), 1994
(49.0)
IPT: 2015 (50.0), 1931 (48.8), 1902 (47.3), 2009/1972 (47.2),
1913 (46.3)
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...FITZGERALD/LAMBERT
SHORT TERM...FITZGERALD/LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...STEINBUGL
CLIMATE...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
200 AM EST MON NOV 23 2015
.SYNOPSIS...
A HIGH AMPLITUDE UPPER TROUGH EXTENDING FROM CENTRAL CANADA TO
THE EASTERN U.S. WILL BRING MAINLY DRY CONDITIONS AND BELOW
NORMAL TEMPERATURES THROUGH TUESDAY. A GRADUAL WARMUP AND
CONTINUED DRY WEATHER WILL FOLLOW FOR WEDNESDAY THROUGH FRIDAY AS
A LARGE AREA OF HIGH PRESSURE DRIFTS EAST AND OFF THE MID ATLANTIC
SEABOARD. A COLD FRONT WILL MOVE SOUTHEAST ACROSS THE STATE LATE
FRIDAY INTO SATURDAY WITH THE NEXT CHANCE OF RAIN
SHOWERS...CHANGING TO SCATTERED SNOW SHOWERS ON SATURDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
A LOW PWAT AIR MASS...RELATIVELY LOW SUBSIDENCE INVERSION HGTS OF
JUST 4-5 KFT AGL OR SO...AND LIMITED MFLUX OFF OF LK ERIE FROM
CROSS LAKE/NWRLY FLOW WILL LEAD TO CLOUDS AND THE LIKELIHOOD OF
MAINLY LIGHT SNOW SHOWERS ACROSS WARREN AND MCKEAN COUNTIES EARLY
TODAY... WHILE SKIES ACROSS MUCH OF THE REST OF THE REGION WILL
BE CLEAR TO PARTLY CLOUDY.
05Z HRRR SHOWS ALMOST NO MEASURABLE SNOW FALLING FROM THE
GENERALLY SHALLOW STRATO CU DECK ACROSS THE NW MTNS...THOUGH SFC
OBS BENEATH THIS CLOUD SHIELD /SUCH AS KELZ/ SUGGESTS THAT
ADDITIONAL LIGHT ACCUMS OF SNOW /ANOTHER COATING TO 1.5 INCHES/
COULD OCCUR THIS MORNING INVOF KBFD AND AREAS TO THE WEST ACROSS
WARREN COUNTY.
LOW TEMPS EARLY THIS MONDAY SHOULD DIP INTO THE UPPER TEENS
ACROSS SOME NORTHERN AND WESTERN MTN LOCATIONS...WITH THE REST OF
THE REGION SEEING MINS IN THE 20S.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 8 AM TUESDAY/...
A WEAK CLIPPER WILL MOVE QUICKLY SE FROM THE UPPER GLAKES THIS
AFTERNOON INTO TUESDAY. WAA AHEAD OF THIS SYSTEM COULD PRODUCE A
BIT OF LGT SNOW/FLURRIES THIS EVENING...MAINLY OVR THE NW MTNS.
BLEND OF LATEST MDL OUTPUT SUPPORTS NOTHING MORE THAN A FRESH
DUSTING OVER THE NW COUNTIES.
HIGH TEMPS THIS AFTERNOON WILL RANGE FROM NEAR 32F OVR THE HIGHER
TERRAIN OF NRN AND WRN PENN...TO THE LOWER 40S ACROSS THE
SOUTHEAST PART OF OUR CWA.
IN GENERAL...WINDS SHOULD BE FAIRLY LIGHT BENEATH SFC RIDGE AS IT
SLIDES EAST ACROSS PENN TODAY. HOWEVER...BUFKIT SUGGESTS SW WINDS
COULD GUST AS HIGH AS 20KTS ACROSS THE W MTNS LATE TODAY...AS
THE LLVL P-GRADIENT TIGHTENS BETWEEN WEAK LOW PRESSURE OVR THE
GRT LKS...AND HIGH PRES OVR THE SOUTHERN STATES.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
A MODERATION OF TEMPERATURES WILL BE STARTING NEAR THE BEGINNING
OF THE LONG TERM PERIOD AS UPPER PATTERN TRANSITIONS TOWARD MORE
ZONAL FLOW EARLY IN THE WEEK...THEN SOUTHWESTERLY FLOW IN RISING
HEIGHTS IN RESPONSE TO A DIGGING UPPER TROF OVER THE WESTERN U.S.
INTERMOUNTAIN REGION.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT
ISSUED AT 134 AM EST MON NOV 23 2015
IR SATELLITE LOOP SHOWS AREA OF MVFR TO LOW VFR CIGS COVERING THE
NW 1/3 OF THE AIRSPACE PUSHING SOUTHEAST APPROACHING FIG/UNV/IPT.
LIGHT SNOW SHOWERS/FLURRIES MAY ALSO EXPAND ACROSS THIS AREA BUT
ISOLD VIS RESTRICTIONS SHOULD BE LIMITED TO MVFR. EXPECT LINGERING
SNOW TO DIMINISH BY THE AFTERNOON WITH MAINLY VFR CONDITIONS. SFC
WINDS 8-10KTS FROM 280-320 DEGREES THROUGH THE AFTERNOON /GUSTS
15-20KTS AT MDT-LNS/ WILL DECREASE AND BACK TO 200-250 DEGREES BY
TONIGHT. VFR SHOULD PREVAIL AT MOST SITES OVERNIGHT BUT MVFR CIGS
COULD RETURN TO THE NW AIRSPACE BY EARLY TUESDAY MORNING.
OUTLOOK...TUESDAY-FRIDAY
TUE...MVFR CIGS AND SCATTERED SNOW SHOWERS PSBL NW.
WED...VFR/NO SIG WX EXPECTED.
THU...LOW CIGS PSBL/NO SIG WX EXPECTED.
FRI...VFR/MVFR WITH RAIN SHOWERS PSBL MAINLY FRIDAY NIGHT.
&&
.CLIMATE...
UPDATED AT 138 AM EST SUN NOV 22 2015
WITH 9 DAYS LEFT IN THE MONTH...PRELIMINARY CLIMATE DATA
INDICATES THAT NOVEMBER 2015 CURRENTLY RANKS AS THE WARMEST
NOVEMBER ON RECORD AT OUR TWO LONG TERM CLIMATE SITES: HARRISBURG
AND WILLIAMSPORT. A CONTINUOUS WEATHER RECORD HAS BEEN KEPT AT
EACH SITE SINCE 1888 AND 1895 RESPECTIVELY.
THROUGH 11/21...
THE AVG. MONTHLY TEMPERATURE AT HARRISBURG IS 52.7 DEGREES OR
+6.9 DEGREES ABOVE NORMAL.
THE AVG. MONTHLY TEMPERATURE AT WILLIAMSPORT IS 50.4 DEGREES OR
+7.1 DEGREES ABOVE NORMAL.
THE TOP 5 WARMEST NOVEMBERS (CURRENT RANKINGS)
MDT: 2015 (52.7), 1931 (51.3), 1975 (50.0), 1999 (49.3), 1994
(49.0)
IPT: 2015 (50.4), 1931 (48.8), 1902 (47.3), 2009/1972 (47.2),
1913 (46.3)
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT/FITZGERALD
LONG TERM...LAMBERT/GARTNER
AVIATION...STEINBUGL
CLIMATE...STEINBUGL
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
928 AM EST MON NOV 23 2015
...WIDESPREAD FROST AND FREEZE CONDITIONS LIKELY TONIGHT AWAY FROM
THE COAST...
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND ACROSS THE REGION THROUGH THE END OF THE
WEEK. A WEAK COASTAL TROUGH COULD FORM DURING THE MIDDLE OF THE WEEK
JUST OFF THE SOUTHEAST COAST. A COLD FRONT IS EXPECTED TO DROP
THROUGH THE AREA FROM THE NORTH OVER THE WEEKEND...FOLLOWED BY A
STORM SYSTEM FROM THE WEST EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL EXTEND ACROSS THE REGION TODAY. LOW-LEVEL
THICKNESS SCHEMES COUPLED WITH THE LATEST RAP FORECAST SOUNDINGS
SUPPORT HIGHS FROM THE LOWER 50S NORTH TO THE UPPER 50S ALONG THE
ALTAMAHA RIVER. WINDS HAVE DIMINISHED ENOUGH ON LAKE MOULTRIE TO
CANCEL THE LAKE WIND ADVISORY A BIT EARLY. THE FORECAST IS VERY
MUCH ON TRACK AND DID NOT REQUIRE ANY MEANINGFUL CHANGES.
WITH REGARDS TO TONIGHT...A WIDESPREAD FREEZE IS EXPECTED ACROSS
INLAND AREAS. INCOMING DATA SUPPORT THE ONGOING FREEZE WARNING
AREA WHERE A FREEZE OF 4-7 HOURS IS LIKELY. THE FREEZE IS A BIT
MORE MARGINAL ACROSS ALONG THE LOWER SOUTH CAROLINA COASTAL
COUNTIES AND SOUTH OF THE I-16 CORRIDOR...THERE A FREEZE WATCH IS
CURRENTLY VALID. THE FREEZE WATCH WILL EITHER BE UPGRADED TO A
FREEZE WARNING OR A FROST ADVISORY LATER TODAY AFTER THE FULL
SUITE OF 12Z MODEL DATA ARE REVIEWED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
TONIGHT...HIGH PRESSURE WILL NUDGE CLOSER SETTING UP SOUTHEAST
MONDAY NIGHT...SETTING UP FAVORABLE RADIATIONAL COOLING. WITH
DEWPOINTS IN THE 20S TEMPERATURES WILL FALL QUICKLY AFTER SUNSET
AND SHOULD REACH NEAR 30 FOR MOST INLAND AREAS AND CLOSER TO 40
NEAR THE COAST. WE HAVE A FREEZE WARNING UP FOR NORTHERN AND
WESTERN PORTIONS OF THE FORECAST AREA WHERE THERE IS A HIGHER
LIKELIHOOD OF FREEZING TEMPERATURES...MAINLY NORTH AND WEST OF
CHARLESTON...BEAUFORT...SAVANNAH AND CLAXTON. ELSEWHERE EXCEPT
ALONG THE GEORGIA COAST THERE IS A FREEZE WATCH FOR THE POTENTIAL
OF FREEZING TEMPERATURES...MAINLY INLAND OF HWY 17 IN SOUTH
CAROLINA AND WEST OF I-95 IN GEORGIA. IN ADDITION...MOST AREAS
AWAY FROM THE IMMEDIATE COAST SHOULD SEE FROST SO THOSE FOLKS WITH
SENSITIVE VEGETATION ARE URGED TO TAKE PROPER PRECAUTIONS.
TUESDAY AND TUESDAY NIGHT...BENEATH A NEARLY ZONAL FLOW ALOFT...A
LARGE AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
NORTHWEST. A VERY DRY ATMOSPHERIC COLUMN WILL RESULT IN MAINLY CLEAR
SKIES THROUGH AT LEAST TUESDAY EVENING. TEMPERATURES WILL REMAIN
BELOW NORMAL...BUT START A SLOW MODERATING TREND WITH HIGHS IN THE
LOWER 60S AND NIGHTTIME LOWS IN THE MID TO UPPER 30S WELL INLAND AND
LOWER TO MID 40S CLOSER TO THE COAST...BUT NEAR 50 ALONG PARTS OF
THE IMMEDIATE GEORGIA COAST.
WEDNESDAY AND WEDNESDAY NIGHT...THE SURFACE HIGH WILL BUILD
SOUTHWARD INTO THE REGION AS IT SHIFTS ACROSS NEW ENGLAND ON
WEDNESDAY AND EVENTUALLY EAST OF NOVA SCOTIA WEDNESDAY NIGHT. AS
THIS OCCURS...A WEAK COASTAL TROUGH IS EXPECTED TO TAKE SHAPE JUST
OFF THE SOUTHEAST U.S. COAST. AN ENHANCED NORTHEAST FLOW WILL ADVECT
LOW LEVEL MOISTURE ONSHORE RESULTING IN AN INCREASE IN CLOUD COVER.
ISOLATED SHOWERS COULD DEVELOP ALONG THE IMMEDIATE SOUTHEAST GEORGIA
COAST ON WEDNESDAY...AND BECOME MORE PROBABLE FOR ALL COASTAL AREAS
BY WEDNESDAY NIGHT. HIGHS DURING THE DAY WILL BE IN THE MID 60S MOST
AREAS...WITH LOWS WEDNESDAY NIGHT RANGING FROM THE MID 40S WELL
INLAND TO THE MID 50S ALONG THE GEORGIA COAST.
THANKSGIVING DAY...UPPER LEVEL RIDGING WILL EXPAND OVER THE REGION
FROM THE SOUTHERN GULF OF MEXICO AS SURFACE HIGH PRESSURE SHIFTS
WELL OUT INTO THE ATLANTIC...HELPING TO MAINTAIN A NORTHEAST FLOW
ACROSS THE AREA. ISOLATED SHOWERS WILL STILL BE POSSIBLE FOR COASTAL
AREAS GIVEN THE INFLUX OF ATLANTIC MOISTURE AND SOME LOW LEVEL
CONVERGENCE NEAR THE COAST. BENEATH THE STRENGTHENING RIDGE...HIGHS
SHOULD BE IN THE UPPER 60S TO AROUND 70 ACROSS THE AREA.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
UPPER LEVEL RIDGING WILL EXTEND OVER THE REGION FROM THE GULF OF
MEXICO LATE IN THE WEEK INTO THE START OF THE WEEKEND...BEFORE
FLATTENING OUT AS AN UPPER LEVEL TROUGH PASSES OFF THE MID-ATLANTIC
COAST LATE SATURDAY AND SATURDAY NIGHT. A POTENT UPPER LEVEL LOW
WILL THEN TRACK EASTWARD FROM THE NORTHERN PLAINS TO THE UPPER
MISSISSIPPI VALLEY/OHIO VALLEY LATE IN THE WEEKEND INTO EARLY NEXT
WEEK. MEANWHILE AT THE SURFACE...HIGH PRESSURE WILL PREVAIL OVER THE
AREA ON FRIDAY. MODELS THEN DIVERGE WITH THE GFS INDICATING A
BACKDOOR COLD FRONT DROPPING THROUGH THE AREA OVER THE WEEKEND...BUT
THE ECMWF KEEPS THE FRONT TO THE NORTH. A STORM SYSTEM THEN
APPROACHES FROM THE WEST EARLY NEXT WEEK.
AS FOR EXPECTED WEATHER CONDITIONS...RAIN-FREE CONDITIONS WILL
PREVAIL ON FRIDAY AND SATURDAY...BUT A SLIGHT CHANCE OF SHOWERS IS
POSSIBLE ON SUNDAY DEPENDING ON THE POSITION OF THE FRONT. RAIN
PROBABILITIES THEN INCREASE WELL INTO THE CHANCE CATEGORY SUNDAY
NIGHT THROUGH MONDAY WITH THE APPROACHING STORM SYSTEM. TEMPERATURES
WILL RISE ABOVE NORMAL FRIDAY AND SATURDAY...THEN LIKELY FALL BELOW
NORMAL FOR SUNDAY AND MONDAY.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
VFR.
EXTENDED AVIATION OUTLOOK...VFR.
&&
.MARINE...
TODAY AND TONIGHT...HIGH PRESSURE WILL BUILD INTO THE AREA MEANING
GENERALLY IMPROVING CONDITIONS AS THE PRESSURE GRADIENT AND COLD
ADVECTION DIMINISH. SMALL CRAFT ADVISORIES REMAIN UP FOR THE NEAR
SHORE WATERS THROUGH EARLY AFTERNOON AND BEYOND 20 NM THROUGH
AROUND MIDNIGHT.
TUESDAY THROUGH SATURDAY...HIGH PRESSURE WILL CONTINUE TO BUILD OVER
THE WATERS AND PERSIST INTO MID-WEEK. A TROUGH OF LOW PRESSURE WILL
THEN DEVELOP MID-WEEK...LEADING TO A STRONGER PRESSURE GRADIENT OVER
THE COASTAL WATERS WITH ENHANCED NORTHEAST FLOW. SMALL CRAFT
ADVISORIES APPEAR TO RETURN ON WEDNESDAY FOR MOST WATERS OUTSIDE THE
CHARLESTON HARBOR...AND COULD PERSIST INTO AT LEAST LATE WEEK.
&&
.TIDES/COASTAL FLOODING...
TIDE LEVELS WILL BE ELEVATED THROUGH THE WEEK DUE TO THE FULL
MOON...LUNAR PERIGEE AND PERSISTENT NORTHEAST WINDS. TIDAL
FLOODING COULD REACH MODERATE LEVELS BY THE TUESDAY MORNING HIGH
TIDE...AND MINOR TO MODERATE TIDAL FLOODING WILL THEN BE POSSIBLE
WITH EACH HIGH TIDE CYCLE THROUGH AT LEAST MID-WEEK...IF NOT
LONGER. THE MORNING HIGH TIDE CYCLE APPEARS TO BE THE GREATER OF
THE TWO...AND THERE IS INCREASING CONCERN THAT MAJOR COASTAL
FLOODING COULD BE AN ISSUE WEDNESDAY AND POSSIBLY THURSDAY MORNING
GIVEN STRONG NORTHEAST WINDS JUST OFFSHORE.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...FREEZE WARNING FROM 1 AM TO 9 AM EST TUESDAY FOR GAZ087-088-
099>101.
FREEZE WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING FOR
GAZ114>116-118-137-138.
SC...FREEZE WARNING FROM 1 AM TO 9 AM EST TUESDAY FOR SCZ040-
042>045-047-052.
FREEZE WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING FOR
SCZ048>051.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR AMZ350-
352.
SMALL CRAFT ADVISORY UNTIL 1 AM EST TUESDAY FOR AMZ374.
SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ330.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
646 AM EST MON NOV 23 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 450 AM EST MON NOV 23 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A TROF EXTENDING S THRU
THE GREAT LAKES REGION. SHEARED OUT SHORTWAVE/LEFT EXIT OF 120+KT
UPPER JET EXTENDING FROM SASKATCHEWAN INTO THE UPPER MISSISSIPPI
VALLEY HAS GENERATED SOME AREAS OF -SN INTO WRN UPPER MI OVERNIGHT.
MODELS OVER THE LAST DAY OF RUNS CORRECTLY TRENDED LIGHTER WITH THIS
PCPN AS SNOW THAT HAS OCCURRED HAS BEEN VERY LIGHT WITH NOT MUCH
MORE THAN A DUSTING OF ACCUMULATION WHERE SNOW HAS FALLEN PER
WEBCAMS. TO THE E...JUST AS SOME HIGH RES MODELS WERE INDICATING 24
HRS AGO...THE REGIONAL CANADIAN IN PARTICULAR...A BURST OF HVY SNOW
MOVED N OFF NRN LAKE MI INTO PARTS OF THE ERN U.P. OVER THE LAST
SEVERAL HRS. IT APPEARS THE EXTREME SE CORNER OF LUCE COUNTY
PROBABLY SAW A VERY BRIEF PERIOD OF MDT TO HVY SNOW AROUND 06Z. THAT
AREA OF MDT/HVY SNOW HAS SHIFTED E INTO THE STRAITS VCNTY SINCE
THEN.
THERE IS STILL SOME CONCERN FOR LAKE ENHANCED SNOW OFF NRN LAKE MI
TO SHIFT/REFORM BACK TO THE W TODAY. ON THE HIGH EXTREME IS THE
REGIONAL CANADIAN WHICH GENERATES 0.3 INCHES OF QPF IN THE FAR SE
CORNER OF LUCE COUNTY BTWN 15Z AND 00Z. SINCE THE MAJORITY OF AVBL
HIGH RES GUIDANCE...INCLUDING THE HIGH RES CANADIAN...KEEPS THE BULK
OF REDEVELOPING LAKE ENHANCED SNOW JUST E OF LUCE COUNTY...WILL KEEP
SNOW AMOUNTS UNDER ADVY CRITERIA WITH PERHAPS 1.5-2 INCHES TO THE SE
OF KERY. ELSEWHERE....PATCHY -SN MOVING ACROSS WRN UPPER MI ATTM
SHOULD DISSIPATE OVER THE NEXT SEVERAL HRS AS IT SHIFTS E AND HAS TO
OVERCOME INITIAL DRY LOWER LEVEL AIR. THEN...A SFC LOW PRES TROF
WILL SWING INTO WRN UPPER MI LATE MORNING/AFTN...BRINGING A WIND
SHIFT TO THE W TO NW. EXPECT -SHSN TO ACCOMPANY THE TROF AS OVERLAKE
INSTABILITY WITH 850MB TEMPS AROUND -7C WILL BE MORE THAN SUFFICIENT
TO GENERATE -SHSN ALONG THE TROF/CONVERGENCE ZONE AS IT CROSSES WRN
LAKE SUPERIOR. THIS WILL THEN TRANSITION TO SCT LAKE EFFECT
-SHSN INTO TONIGHT FOR AREAS FAVORED BY NW WINDS AS 850MB TEMPS DROP
A DEGREE OR TWO C. INITIALLY...INVERSION IS UP AROUND 7KFT THIS
EVENING...BUT FALLS TO AROUND 4KFT W OVERNIGHT AND TO AROUND 5KFT E
LATE. DESPITE THE DECENTLY HIGH INVERSION HEIGHTS...SNOW
ACCUMULATIONS WILL BE LIMITED DUE TO THE DGZ BEING ABOVE THE
CONVECTIVE LAYER. AT THIS POINT...EXPECT ACCUMULATIONS MOSTLY UNDER
1 INCH...BUT IF ANY RELATIVELY STATIONARY BANDS SET UP...THERE
CERTAINLY COULD BE ISOLATED 2-3 INCH AMOUNTS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 422 AM EST MON NOV 23 2015
...RAIN CHANGING TO SNOW WED NIGHT INTO THANKSGIVING DAY WITH
ACCUMULATING SNOW POSSIBLE INTO THU NIGHT...
IN LARGER SCALE...DEEP TROUGH OVER EASTERN CONUS SLIDES TO EASTERN
CANADA ON TUE WHILE SPLIT FLOW TROUGHING DEVELOPS WESTERN CANADA TO
WESTERN CONUS. 1000-850MB TROUGH FORMING ON TUE OVER ROCKIES AND
ADJACENT PLAINS AND LOW-LEVEL HIGH PRESSURE SETTLING TO SOUTHEAST
CONUS WILL ALLOW S/SE WINDS AT SFC TO BRING INCREASING MOISTURE OFF
THE GULF OF MEXICO TOWARD THE MIDDLE MISSISSIPPI RIVER VALLEY. WILL
STAY DRY OVER UPR LAKES ON TUE BUT LATE TUE NIGHT INTO WED MORNING
SOUNDINGS SHOW INCREASING MOISTURE BLO H9 INTO UPPER GREAT LAKES.
IF THERE IS ANY PRECIP AROUND ON WED MORNING...IT LIKELY WOULD TAKE
FORM OF DZ/FZDZ DEPENDING ON SFC TEMPS. BEST CHANCE FOR LIGHT ICING
WOULD BE OVER INTERIOR CNTRL CWA FM IRON/DICKINSON INTO BARAGA AND
WESTERN MARQUETTE COUNTY. MODELS SOMETIMES ARE TOO OVERDONE ON THIS
TYPE OF LOW-LEVEL MOISTENING BUT IN THIS CASE THERE IS DECENT SNOW
PACK JUST TO THE SOUTH SO THAT MAY HELP THE EXPANSION OF LOW-LEVEL
MOISTURE.
LATER ON WEDNESDAY DEEPER MOISTURE AND LARGER SCALE FORCING INCREASE
STEADILY AHEAD OF SHORTWAVE TROUGH SLIDING OVER MANTIOBA AND
NORTHERN ONTARIO. LOW-LEVEL THETA-E ADVECTION INCREASES BRIEFLY
BEFORE BEING SHUNTED TO THE SOUTH AND EAST ON WED NIGHT. SHOULD SEE
LIGHT RAIN BECOME MORE WIDESPREAD...BUT WITHOUT MUCH OF STRONG
MOISTURE TAP AHEAD OF THE TROUGH WITH THE NORTHERN STREAM SHORTWAVE
TROUGH...RAINFALL AMOUNTS SHOULD BE LIGHT. COOLER AIR WITH H85 TEMPS
DOWN BLO -2C SLIDES IN AFTER MIDNIGHT WED NIGHT OVER THE WEST AND
THAT SHOULD TURN ANY LINGERING RAIN TO SNOW. GFS SOUNDINGS AND H85-
H7 RH FIELDS FM THE ECMWF INDICATE MID-LEVEL DRYING MAY LEAD TO
CHANCES OF FREEZING DRIZZLE OR DRIZZLE INSTEAD OF SNOW LATE WED
NIGHT INTO THANKSGIVING MORNING WITH MOIST LAYER AT TEMPS BLO 0C BUT
MUCH WARMER THAN -10C. UPSLOPE FLOW OFF LK SUPERIOR WOULD ALSO AID
IN LOW-LEVEL LIFT AND MAYBE LEAD TO GREATER CHANCES OF DRIZZLE FOR
WEST AND NCNTRL UPR MICHIGAN. ADDED MENTION OF DZ/FZDZ IN THE GRIDS
FOR THESE AREAS.
ATTN LATER ON THANKSGIVING TURNS TO WAVE OF LOW PRESSURE THAT RIDES
NORTHEAST ALONG THE TROUGH OVER THE UPR GREAT LAKES. 00Z ECMWF
TRENDED FARTHER WEST WITH THE WAVE WHILE THE GFS TRENDED FARTHER
EAST. IF THE ECMWF IS CORRECT SWATH OF MODERATE PRECIP WOULD LIFT
BACK OVER AT LEAST THE SOUTH AND EAST CWA THANKSGIVING AFTN INTO
THU NIGHT. SINCE THE INITIAL TROUGH/COLD FRONT IS THROUGH MOST CWA
PTYPE WOULD MOSTLY BE SNOW...EXCEPT OVER FAR SCNTRL WHERE WARM AIR
LINGERS AS EVEN ECMWF SHOWS H85 TEMPS AT LEAST +1C WHEN HEAVIER QPF
IS FORECAST TO MOVE THROUGH. SFC TEMPS STILL MID 30S AS WELL SO NO
RISK OF ANY FREEZING PRECIP EITHER. JUST INLAND OVER SOUTH CENTRAL
AND OVER MOST OF THE EASTERN CWA /N WINDS LEADING TO OFFSHORE WINDS
AT ESC AND ISQ/ COULD SEE SEVERAL INCHES OF WET SNOW WITH THE ECMWF
SOLN AS 12 HR QPF BTWN 18Z THU AND 06Z FRI IS AT LEAST 0.5 IF NOT UP
TO 0.75 INCH. MEANWHILE...LATEST GFS BARELY IS OVER 0.25 INCHES FOR
THAT TIME FRAME. GEM IS MORE LIKE THE ECMWF WITH TOTAL QPF...BUT MUCH
WARMER AND WOULD RESULT IN MOSTLY RAIN FOR THOSE AREAS. WPC PREFERRED
CONSENSUS OF GFS/ECMWF/GEM. WILL CONTINUE TO MENTION THE RAIN TO SNOW
AND SOME ACCUMULATING SNOW IN THE HWO...BUT CANNOT PLAY UP THE SNOW
TOO MUCH OR GET TOO SPECIFIC YET GIVEN THE UNCERTAINTIES THAT REMAIN.
BEHIND THIS SYSTEM...TURNS COLD ENOUGH FOR LAKE EFFECT SNOW SHOWERS
OFF LK SUPERIOR FRI INTO FRI NIGHT. ON FRI...AREAS FAVORED BY N
WINDS MAY SEE SOME SNOW FOR A CHANGE...THEN WOULD BE MAINLY NW FLOW
AREAS FRI NIGHT. DRY LOW-LEVEL AIRMASS WITH STRONG HIGH BUILDING IN
SHOULD LIMIT EXTENT OF LES. BASED ON CURRENT MODEL SOLUTIONS IT IS
DOUBTFUL AMOUNTS WOULD REACH ADVY LEVELS FRI-FRI NIGHT. SLIGHT
WARMING TREND WITH GENERALLY DRY WEATHER IS EXPECTED FOR NEXT
WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 644 AM EST MON NOV 23 2015
A DISTURBANCE MOVING ACROSS THE REGION WILL BRING SOME PATCHY -SN
THIS MORNING. WITH THE PASSAGE OF A SFC TROF...LAKE EFFECT -SHSN
WILL DEVELOP FOR AREAS FAVORED BY NW WINDS THIS AFTN AND TONIGHT.
FOR KCMX/KIWD...THIS MEANS MVFR CONDITIONS SHOULD PREVAIL THRU THE
FCST PERIOD. AT KSAW...VFR CONDITIONS SHOULD PREVAIL THIS MORNING
UNDER LINGERING DRIER AIR AT THE LOW LEVELS...THOUGH THERE MAY A
PERIOD OF MVFR VIS IN -SN. VFR SHOULD CONTINUE INTO THE MID AFTN
WITH A DOWNSLOPE WESTERLY WIND. MVFR CONDITIONS SHOULD THEN DEVELOP
AT KSAW LATE AFTN AND CONTINUE THRU TONIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 AM EST MON NOV 23 2015
NO GALES ARE EXPECTED ON LAKE SUPERIOR THRU THE END OF THE WEEK.
PREVIOUSLY...THERE WERE INDICATIONS OF A GALE EVENT THU NIGHT/FRI
AFTER A COLD FRONT PASSES. HOWEVER...IT NOW APPEARS THAT THE FRONT
WILL BE WEAKER SO THAT WINDS WILL REMAIN BLO GALE FORCE. LIGHTEST
WINDS THIS WEEK WILL OCCUR TUE AS A HIGH PRES RIDGE QUICKLY SHIFTS
ACROSS THE UPPER GREAT LAKES. STRONGEST WINDS THIS WEEK WILL OCCUR
LATE TUE NIGHT/WED OVER THE E HALF OF LAKE SUPERIOR IN THE SOUTHERLY
FLOW AHEAD OF THE AFOREMENTIONED COLD FRONT AND THEN LATE THU/FRI
AFTER THE FRONT PASSES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GLASGOW MT
904 AM MST MON NOV 23 2015
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH WEDNESDAY...
MORNING UPDATE...
CHANGES FOR THIS MORNING WERE FOCUSED ON THE LIGHT ECHOS ACROSS
THE AREA. A LARGE HOLE EXISTS AROUND THE RADAR ON COMPOSITE MODE
AND THEREFORE MOST OF THESE ECHOS ARE NOT REACHING THE GROUND.
HOWEVER... WHERE ECHOS EXCEED ROUGHLY 20 TO 25 DBZ SOME LIGHT
FLURRIES WILL BE POSSIBLE. SO, HAVE UPDATED WX GRIDS TO INCLUDE
FLURRIES THROUGH THE EARLY AFTERNOON. RAP WAS USED TO BLEND INTO
THE POPS TO ACCOUNT FOR FLURRIES AS IT SEEMS TO BE ABOUT THE MOST
ACCOUNTABLE MODEL AT THE MOMENT. SKY CONDITIONS WERE ALSO TWEAKED
SLIGHTLY TO INCLUDE THESE BANDS OF ECHOS PASSING THROUGH. GAH
PREVIOUS SHORT TERM DISCUSSION...
THE UPPER LEVEL RIDGE FLATTENS OUT TODAY RESULTING IN ZONAL FLOW
ALOFT. OFF TO THE WEST A FAST MOVING UPPER TROUGH WILL BE DROPPING
SOUTH FROM THE GULF OF ALASKA AND NORTHERN BC. THIS WILL PUSH
COLDER AIR SOUTH INTO NORTHEAST MONTANA TODAY. BY 00Z THIS EVENING
THE BASE OF THE TROUGH WILL BE TO THE WEST OF WASHINGTON AND BC
EJECTING MOISTURE INTO THE SOUTHERN BC AND ALBERTA. THE FLOW
DIRECTION WILL AVOID OUR AREA UNTIL TUESDAY. SO EXPECT COOLER BUT
CONTINUED DRY CONDITIONS THROUGH TONIGHT. MODELS SUGGEST TUESDAY
MORNING AND MUCH OF TUESDAY AFTERNOON STAYING DRY WHILE CLOUDS
INCREASE FROM THE NORTHWEST AS THE COLD FRONT DESCENDS INTO
MONTANA. THE TROUGH BEGINS TO SPLIT APART WITH THE SOUTHERN
PORTION HEADING INTO NORTHERN CALIFORNIA...WHERE IT KEEPS PICKING
UP PACIFIC MOISTURE.
TUESDAY NIGHT AND WEDNESDAY...THE FAST-MOVING STORM IMPACTS THE
LOCAL REGION WITH CAA FROM WIND THAT SHIFTS TO THE NORTH AND
PRECIPITATION THAT STARTS AS RAIN...BUT TURNS INTO ACCUMULATING
SNOW. AT 00Z WEDNESDAY...LIGHT PRECIPITATION IS JUST MOVING INTO
OUR WESTERN COUNTIES. THEN IT SPREADS TOTALLY ACROSS THE AREA
OVERNIGHT. AS THE MODELS EVOLVE CLOSER TO THE EVENT...GFS QPF
CONTINUES TO TREND LOWER FOR THE CWA...AS EVIDENCED BY THE WPC
WINTER DESK ANALYSIS. THE HEAVIEST GFS QPF WILL BE THROUGH
CENTRAL MONTANA...THEN SOUTHEAST MONTANA. LOCALLY...QPF SHOULD BE
HEAVIEST IN OUR SOUTHWEST AREAS. THE NAM IS MUCH MORE WET WITH QPF
AMOUNTS ACROSS SOUTHERN PORTIONS OF THE CWA. DUE TO MODEL
DIFFERENCES...WILL CONTINUE TO GO WITH A BLEND. MOST
PRECIPITATION WILL END NORTH OF THE MISSOURI RIVER BEFORE NOON
WEDNESDAY...AND BEFORE MIDNIGHT SOUTH OF THE MISSOURI. WHAT WILL
BE LEFT ARE ROADS THAT MAY BE AFFECTED BY SNOW AND ICE WHICH COULD
CAUSE HOLIDAY TRAVEL PROBLEMS. SCT
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...
HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE AREAS WEDNESDAY
NIGHT. THIS WILL PUSH THE SNOW COMPLETELY SOUTH OF THE FORECAST
AREA DURING THE NIGHT POSSIBLY SOONER. WILL MAINTAIN A CHANCE OF
SNOW IN THE SOUTH FOR NOW. TEMPERATURES WILL BE SOMEWHAT COLDER
THAN NORMAL BUT NOT BITTER COLD AS LOWS IN THE SINGLE DIGITS ARE
EXPECTED IN MOST AREAS.
THE SURFACE HIGH WILL CONTINUE TO BRING DRY WEATHER ON THURSDAY. A
NORTH TO NORTHWEST FLOW ALOFT IN THE NORTHERN BRANCH UPPER TROUGH
WILL KEEP TEMPERATURE ABOUT 10 DEGREES BELOW NORMAL.
UPPER LEVEL HIGH BUILDS INTO WESTERN CANADA FRIDAY AND SATURDAY
WHILE CLOSED UPPER LOW REMAINS OVER NEVADA AND CALIFORNIA. THIS
WILL RESULT IN AN UNUSUAL NORTHEAST TO EAST FLOW ALOFT. SINCE THE
FLOW ALOFT WILL BE ANTI-CYCLONIC...LOOK FOR DRY WEATHER TO
CONTINUE WITH MODERATING TEMPERATURES.
MODEL DIFFERENCES START APPEARING OVER THE WEEKEND AS THE GFS
WANTS TO BRING THE UPPER LOW TO THE SOUTH TOWARDS MONTANA ON
SUNDAY WHILE ECMWF WANTS TO RIDGE THE UPPER HIGH INTO THE AREA AND
KEEP THE LOW TO THE SOUTH. WILL LEAN TOWARDS THE DRIER ECMWF FOR
NOW AND CONTINUE THE WARMING TREND FOR NOW. THE ECMWF MAINTAINS
THAT RIDGE ON MONDAY WHILE THE GFS MOVES THE LOW TO THE EAST. FORRESTER
&&
.AVIATION...
VFR WITH A MIX OF MID AND HIGH CLOUDS TODAY AND TONIGHT. A FEW
FLURRIES MAY ALSO OCCUR AS A WARM FRONT LIFTS ACROSS THE REGION
TODAY.
VARIABLE WINDS LESS THAN 10 KNOTS EARLY WILL BECOME EAST TO
SOUTHEAST 10 TO 15 KNOTS BY AFTERNOON AND CONTINUE TONIGHT.
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS BISMARCK ND
638 AM CST MON NOV 23 2015
.UPDATE...
ISSUED AT 635 AM CST MON NOV 23 2015
NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE CYCLE OTHER THAN
BLENDING RECENT OBSERVATIONS WITH SHORT TERM MODEL GUIDANCE. RADAR
ECHOES IN NORTHEASTERN MT REFLECT AN INCREASE IN MIDDLE- AND HIGH-
LEVEL CLOUDS AND NOT PRECIPITATION DUE TO A DRY LOWER ATMOSPHERE.
THAT SCENARIO IS WELL-REFLECTED BY RECENT HRRR ITERATIONS AND THUS
THE DRY FORECAST FOR TODAY APPEARS TO BE WELL IN HAND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 337 AM CST MON NOV 23 2015
QUIET WEATHER HIGHLIGHTS THE SHORT TERM PERIOD.
CURRENTLY...THE STRONG LOW PRESSURE SYSTEM ASSOCIATED WITH
YESTERDAY`S WINDY CONDITIONS WAS CENTERED OVER THE BORDER OF
MANITOBA/ONTARIO/MINNESOTA. A WEAK HIGH PRESSURE AXIS EXTENDED FROM
SOUTHERN ALBERTA SOUTHEASTWARD INTO EASTERN MONTANA AND THE WESTERN
DAKOTAS...WITH BROAD LOW PRESSURE DEVELOPING IN THE LEE OF THE
ROCKIES.
TODAY THE STRONG LOW PRESSURE SYSTEM IS FORECAST TO MOVE EAST
TOWARDS THE GREAT LAKES AND HUDSON BAY...AND THE SURFACE HIGH
PRESSURE RIDGE AXIS MOVES EASTWARD INTO THE CENTRAL AND EASTERN
DAKOTAS AS AN UPPER LEVEL RIDGE BUILDS/EXPANDS FROM THE ROCKIES INTO
THE WESTERN PLAINS. MAINLY PARTLY CLOUDY SKIES TODAY WITH
MIDDLE/HIGH CLOUDS MOVING EAST INTO NORTH DAKOTA. WARMER AIR IN
SOUTHWESTERN NORTH DAKOTA WITH HIGHS IN THE LOWER 40S...WITH COOLER
AIR TO THE NORTHEAST WITH HIGHS IN THE MID TO UPPER 30S.
TONIGHT THE BROAD UPPER LEVEL RIDGE MIGRATES EASTWARD AND THE FLOW
OVER THE ROCKIES BECOMES SOUTHWESTERLY ALOFT. IN RESPONSE...BROAD
SURFACE LOW PRESSURE DEVELOPS OVER THE ROCKIES AND FRONT RANGE...AND
A LONG BROAD FETCH OF SOUTHERLY SURFACE WINDS DEVELOPS FROM THE
SOUTHERN PLAINS NORTHWARD INTO THE NORTHERN PLAINS. A LOW LEVEL JET
DEVELOPS...AND THIS WILL ALLOW LOW LEVEL MOISTURE TO STREAM
NORTHWARD INTO SOUTH CENTRAL CANADA. LOOK FOR INCREASING LOW CLOUDS
WITH SOUTHEASTERLY SURFACE WINDS...AND INCREASING MID LEVEL CLOUDS
MOVING IN FROM THE WEST/SOUTHWEST. LOW TEMPERATURES ARE EXPECTED TO
BE IN THE 20S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 337 AM CST MON NOV 23 2015
THE FOCUS IN THE LONG TERM IS ON LIGHT SNOW POTENTIAL CENTERED ON
WEDNESDAY. WE ARE BECOMING MORE CONFIDENT THAT ACCUMULATIONS WILL
BE RELATIVELY LOW WITH THIS EVENT...POTENTIALLY LIMITING IMPACTS.
THE 00 UTC MODEL SUITE WAS IN RELATIVELY GOOD AGREEMENT IN SHOWING
LIGHT SNOW DEVELOPING IN WESTERN ND BY EARLY WEDNESDAY MORNING AND
SPREADING EASTWARD DURING THE DAY. THE MULTI-MODEL CONSENSUS CALLS
FOR LIQUID-EQUIVALENT MOISTURE VALUES OF 0.05 TO 0.15 INCHES /MOST
IN FAR SOUTHWESTERN ND/...WHICH SHOULD CONTRIBUTE TO SNOW AMOUNTS
RANGING FROM LESS THAN ONE-HALF INCH TO THE NORTH AND EAST OF THE
MISSOURI RIVER...TO 1 TO 2 INCHES SOUTH AND WEST OF THE MISSOURI
RIVER. OUR OFFICIAL FORECAST PRODUCED 3 INCH SNOW TOTALS ONLY IN
EXTREME SOUTHWESTERN ND...BOWMAN AND SLOPE COUNTIES...WEDNESDAY
THROUGH WEDNESDAY NIGHT.
THE SNOW WILL BE GENERATED IN A POST-FRONTAL ENVIRONMENT...DRIVEN
MAINLY BY DYNAMICS ASSOCIATED WITH A SHORTWAVE TROUGH EMBEDDED IN
THE NORTHERN STREAM OF A SPLIT FLOW. THE 03 UTC SREF LINGERED THE
SNOW LONGER THAN THE 00 UTC DETERMINISTIC GUIDANCE...SO A BIT OF
UNCERTAINTY REMAINS...BUT IN GENERAL GUIDANCE CONTINUED TO SUGGEST
THAT THE PRIMARY VERTICAL MOTION ASSOCIATED WITH THE 500-MB LOW IN
THE GREAT BASIN WILL REMAIN DISPLACED SOUTH OF ND. IF THAT IS THE
CASE...THANKSGIVING DAY MAY END UP COLD...BUT DRY IN MOST AREAS.
ONE OTHER ISSUE WE WILL NEED TO CONSIDER IS WHETHER FOG DEVELOPS
TUESDAY NIGHT...AND WHETHER LINGERING WARM AND DRY AIR ALOFT IS
CAPABLE OF PRODUCING ANY LIGHT FREEZING RAIN OR LIGHT FREEZING
DRIZZLE TUESDAY NIGHT INTO WEDNESDAY MORNING. FORECAST SOUNDINGS
ARE NOT PARTICULARLY SUGGESTIVE OF THAT POTENTIAL THOUGH...SO WE
ARE NOT MESSAGING THAT RISK AT THIS POINT.
A REX BLOCK WILL DEVELOP ALOFT OVER THE WESTERN UNITED STATES BY
NEXT WEEKEND AS THE GREAT BASIN LOW GETS PINCHED OFF TO THE SOUTH
OF A DEVELOPING 500-MB RIDGE OVER WESTERN CANADA. THIS SCENARIO IS
EXPECTED TO GENERATE A WARMING TREND AND MAINLY DRY WEATHER ACROSS
THE AREA NEXT WEEKEND...THOUGH THE 00 UTC GFS /AND THE 00 UTC GFS
ALONE/ DOES SUGGEST SOME SNOW POTENTIAL RETURNING NEXT SUNDAY WHEN
IT BREAKS THE BLOCK DOWN AND KICKS THE REMNANT LOW ALOFT EASTWARD
FURTHER NORTH THAN THE REST OF THE 00 UTC MODEL GUIDANCE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 635 AM CST MON NOV 23 2015
VFR CONDITIONS EXPECTED UNTIL AROUND 02Z-06Z MONDAY EVENING...WHEN
INCREASING LOW CLOUDS WILL RESULT IN MVFR CIGS AT ALL TAF SITES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...JV
LONG TERM...CJS
AVIATION...JV
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1221 PM EST MON NOV 23 2015
...FROST AND FREEZE CONDITIONS TONIGHT...
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND ACROSS THE REGION THROUGH THE END OF THE
WEEK. A WEAK COASTAL TROUGH COULD FORM DURING THE MIDDLE OF THE WEEK
JUST OFF THE SOUTHEAST COAST. A COLD FRONT IS EXPECTED TO DROP
THROUGH THE AREA FROM THE NORTH OVER THE WEEKEND...FOLLOWED BY A
STORM SYSTEM FROM THE WEST EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO CHANGES WERE NEEDED FOR THE EARLY AFTERNOON UPDATE. SEE THE
SHORT TERM PERIOD BELOW FOR INFORMATION ABOUT CHANCES TO THE
FROST/FREEZE HEADLINES.
HIGH PRESSURE WILL EXTEND ACROSS THE REGION TODAY. LOW-LEVEL
THICKNESS SCHEMES COUPLED WITH THE LATEST RAP FORECAST SOUNDINGS
SUPPORT HIGHS FROM THE LOWER 50S NORTH TO THE UPPER 50S ALONG THE
ALTAMAHA RIVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
TONIGHT...CANADIAN HIGH PRESSURE WILL BECOME CENTERED JUST THE
NORTH OVERNIGHT AS HEIGHTS BUILD ALOFT IN THE WAKE OF THE
DEPARTING LONGWAVE TROUGH OFF NEW ENGLAND. THE BOUNDARY LAYER IS
POISED TO DECOUPLE QUICKLY AFTER SUNSET WITH CALM WINDS
DOMINATING FOR MOST LOCATIONS. CALM WINDS...LOW DEWPOINTS AND
CLEAR SKIES WILL PROMOTE STRONG RADIATIONAL COOLING WITH THE
STEEPEST THERMAL DECLINES OCCURRING DURING THE EVENING HOURS. THE
23/12Z GUIDANCE HAS TRENDED SLIGHTLY COOLER SO CONFIDENCE HAS
INCREASED ENOUGH TO UPGRADE THE REMAINING FREEZE WATCH AREA TO A
FREEZE WARNING. A FROST ADVISORY HAS ALSO BEEN ISSUED FOR INLAND
MCINTOSH COUNTY WHERE SCATTERED FROST IS LIKELY...BUT A FREEZE IS
NOT AS CERTAIN. FREEZE DURATIONS OF 5-8 HOURS ARE LIKELY ACROSS
THE FAR INLAND COUNTIES WITH 2-4 HOURS FARTHER EAST AND SOUTH. A
FREEZE IS UNLIKELY FOR DOWNTOWN CHARLESTON AND THE HEART OF
DOWNTOWN SAVANNAH. LOWS WILL RANGE FROM THE UPPER 20S WELL INLAND
TO THE UPPER 40S ALONG THE BEACHES OF NORTH COASTAL GEORGIA.
THERE WILL BE A LARGE THERMAL GRADIENT ACROSS THE SOUTH CAROLINA
COASTAL ZONES TONIGHT WITH TEMPERATURES RANGING FROM 31-32 WEST
OF HIGHWAY 17 AND OUTSIDE OF THE 526 LOOP WITH UPPER 30S IN
DOWNTOWN CHARLESTON AND MID 40S AT THE BEACHES. FOR THE GEORGIA
COASTAL ZONES...THERE MAY BE JUST ENOUGH OF AN ONSHORE COMPONENT
THERE TO KEEP TEMPERATURES WARM ENOUGH TO PRECLUDE SCATTERED
FROST. WILL HOLD OFF ON A FROST ADVISORY FOR THOSE ZONES...ALTHOUGH
IT MAY BE CLOSE IN COMMUNITIES SUCH AS BETHESDA...FAR WESTERN
PORTIONS OF SKIDAWAY ISLAND...HALFMOON LANDING...SHELLMAN BLUFF
AND DARIEN. LOWS LOOK TO GO NO LOWER THAN THE UPPER 40S FOR THE
IMMEDIATE GEORGIA COAST...INCLUDING TYBEE ISLAND.
TUESDAY AND TUESDAY NIGHT...BENEATH A NEARLY ZONAL FLOW ALOFT...A
LARGE AREA OF HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
NORTHWEST. A VERY DRY ATMOSPHERIC COLUMN WILL RESULT IN MAINLY CLEAR
SKIES THROUGH AT LEAST TUESDAY EVENING. TEMPERATURES WILL REMAIN
BELOW NORMAL...BUT START A SLOW MODERATING TREND WITH HIGHS IN THE
LOWER 60S AND NIGHTTIME LOWS IN THE MID TO UPPER 30S WELL INLAND AND
LOWER TO MID 40S CLOSER TO THE COAST...BUT NEAR 50 ALONG PARTS OF
THE IMMEDIATE GEORGIA COAST.
WEDNESDAY AND WEDNESDAY NIGHT...THE SURFACE HIGH WILL BUILD
SOUTHWARD INTO THE REGION AS IT SHIFTS ACROSS NEW ENGLAND ON
WEDNESDAY AND EVENTUALLY EAST OF NOVA SCOTIA WEDNESDAY NIGHT. AS
THIS OCCURS...A WEAK COASTAL TROUGH IS EXPECTED TO TAKE SHAPE JUST
OFF THE SOUTHEAST U.S. COAST. AN ENHANCED NORTHEAST FLOW WILL ADVECT
LOW LEVEL MOISTURE ONSHORE RESULTING IN AN INCREASE IN CLOUD COVER.
ISOLATED SHOWERS COULD DEVELOP ALONG THE IMMEDIATE SOUTHEAST GEORGIA
COAST ON WEDNESDAY...AND BECOME MORE PROBABLE FOR ALL COASTAL AREAS
BY WEDNESDAY NIGHT. HIGHS DURING THE DAY WILL BE IN THE MID 60S MOST
AREAS...WITH LOWS WEDNESDAY NIGHT RANGING FROM THE MID 40S WELL
INLAND TO THE MID 50S ALONG THE GEORGIA COAST.
THANKSGIVING DAY...UPPER LEVEL RIDGING WILL EXPAND OVER THE REGION
FROM THE SOUTHERN GULF OF MEXICO AS SURFACE HIGH PRESSURE SHIFTS
WELL OUT INTO THE ATLANTIC...HELPING TO MAINTAIN A NORTHEAST FLOW
ACROSS THE AREA. ISOLATED SHOWERS WILL STILL BE POSSIBLE FOR COASTAL
AREAS GIVEN THE INFLUX OF ATLANTIC MOISTURE AND SOME LOW LEVEL
CONVERGENCE NEAR THE COAST. BENEATH THE STRENGTHENING RIDGE...HIGHS
SHOULD BE IN THE UPPER 60S TO AROUND 70 ACROSS THE AREA.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
UPPER LEVEL RIDGING WILL EXTEND OVER THE REGION FROM THE GULF OF
MEXICO LATE IN THE WEEK INTO THE START OF THE WEEKEND...BEFORE
FLATTENING OUT AS AN UPPER LEVEL TROUGH PASSES OFF THE MID-ATLANTIC
COAST LATE SATURDAY AND SATURDAY NIGHT. A POTENT UPPER LEVEL LOW
WILL THEN TRACK EASTWARD FROM THE NORTHERN PLAINS TO THE UPPER
MISSISSIPPI VALLEY/OHIO VALLEY LATE IN THE WEEKEND INTO EARLY NEXT
WEEK. MEANWHILE AT THE SURFACE...HIGH PRESSURE WILL PREVAIL OVER THE
AREA ON FRIDAY. MODELS THEN DIVERGE WITH THE GFS INDICATING A
BACKDOOR COLD FRONT DROPPING THROUGH THE AREA OVER THE WEEKEND...BUT
THE ECMWF KEEPS THE FRONT TO THE NORTH. A STORM SYSTEM THEN
APPROACHES FROM THE WEST EARLY NEXT WEEK.
AS FOR EXPECTED WEATHER CONDITIONS...RAIN-FREE CONDITIONS WILL
PREVAIL ON FRIDAY AND SATURDAY...BUT A SLIGHT CHANCE OF SHOWERS IS
POSSIBLE ON SUNDAY DEPENDING ON THE POSITION OF THE FRONT. RAIN
PROBABILITIES THEN INCREASE WELL INTO THE CHANCE CATEGORY SUNDAY
NIGHT THROUGH MONDAY WITH THE APPROACHING STORM SYSTEM. TEMPERATURES
WILL RISE ABOVE NORMAL FRIDAY AND SATURDAY...THEN LIKELY FALL BELOW
NORMAL FOR SUNDAY AND MONDAY.
&&
.AVIATION /17Z MONDAY THROUGH FRIDAY/...
VFR.
EXTENDED AVIATION OUTLOOK...VFR.
&&
.MARINE...
TODAY AND TONIGHT...HIGH PRESSURE WILL BUILD INTO THE AREA MEANING
GENERALLY IMPROVING CONDITIONS AS THE PRESSURE GRADIENT AND COLD
ADVECTION DIMINISH. A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR
THE GEORGIA OFFSHORE WATERS UNTIL 7 PM.
TUESDAY THROUGH SATURDAY...HIGH PRESSURE WILL CONTINUE TO BUILD OVER
THE WATERS AND PERSIST INTO MID-WEEK. A TROUGH OF LOW PRESSURE WILL
THEN DEVELOP MID-WEEK...LEADING TO A STRONGER PRESSURE GRADIENT OVER
THE COASTAL WATERS WITH ENHANCED NORTHEAST FLOW. SMALL CRAFT
ADVISORIES APPEAR TO RETURN ON WEDNESDAY FOR MOST WATERS OUTSIDE THE
CHARLESTON HARBOR...AND COULD PERSIST INTO AT LEAST LATE WEEK.
&&
.TIDES/COASTAL FLOODING...
TIDE LEVELS WILL BE ELEVATED THROUGH THE WEEK DUE TO THE FULL
MOON...LUNAR PERIGEE AND PERSISTENT NORTHEAST WINDS. TIDAL
FLOODING COULD REACH MODERATE LEVELS BY THE TUESDAY MORNING HIGH
TIDE...AND MINOR TO MODERATE TIDAL FLOODING WILL THEN BE POSSIBLE
WITH EACH HIGH TIDE CYCLE THROUGH AT LEAST MID-WEEK...IF NOT
LONGER. THE MORNING HIGH TIDE CYCLE APPEARS TO BE THE GREATER OF
THE TWO...AND THERE IS INCREASING CONCERN THAT MAJOR COASTAL
FLOODING COULD BE AN ISSUE WEDNESDAY AND POSSIBLY THURSDAY MORNING
GIVEN STRONG NORTHEAST WINDS JUST OFFSHORE.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...FREEZE WARNING FROM 1 AM TO 9 AM EST TUESDAY FOR GAZ087-088-
099>101-114>116-118-137-138.
FROST ADVISORY FROM 4 AM TO 9 AM EST TUESDAY FOR GAZ140.
SC...FREEZE WARNING FROM 1 AM TO 9 AM EST TUESDAY FOR SCZ040-
042>045-047>052.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR AMZ374.
&&
$$
ST
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
310 PM CST MON NOV 23 2015
.SHORT TERM...(Tonight)
ISSUED AT 310 PM CST MON NOV 23 2015
Main short-term forecast concern continues to be potential for fog
development tonight as high pressure slides overhead and winds go
light/variable. Several factors point to at least patchy fog,
including nearly calm winds after sunset and increasing boundary
layer moisture due to snow melt. However, the possible fly-in-the-
ointment will be increasing high clouds currently seen on visible
satellite imagery streaming from the Dakotas into Iowa.
All models suggest these clouds will spread into Illinois late
this afternoon then persist through much of the night. Whether
they will be thick enough to limit radiational cooling and prevent
widespread fog is still in question. Several models such as the
NAM and GFS indicate little or no restriction to visby tonight,
while the HRRR is showing fog developing from mid-evening through
the overnight hours. At this point, will mention patchy fog over the
snow cover, generally along/north of the I-74 corridor. Overnight
lows will be in the middle to upper 20s.
&&
.LONG TERM...(Tuesday through Monday)
ISSUED AT 310 PM CST MON NOV 23 2015
Upper level ridging will build into central IL Tuesday providing for
dry conditions with some mid and high cloud cover. The warming trend
will continue slowly with highs reaching the low to mid 40s I-74
northward where snow cover remains...to the low to mid 50s south of
I-70. Lows Tuesday night should drop to only the mid to upper 30s as
increased winds and cloud cover prevent further cooling at the
surface.
By Wednesday...this ridge will slip east of IL allowing increased
southerly flow and a plume of Gulf moisture to nudge eastward into
Illinois. The result will be a continued warming trend with highs
reaching around 50 north of I-74 to the upper 50s from I-70
southward. Chances for precipitation will be arriving in western
portions of the state by evening. 12Z models currently keep this
precipitation light until Thursday/Thanksgiving evening...then
spread heavier amounts around 0.50 inches per 6 hours across the
state from Thursday afternoon through Friday morning. Total rainfall
amounts look to be around 1 to 1.25 inches southeast of Champaign-
Decatur, and 1.5 to 1.75 inches to the northwest. Could see a mix of
light snow with the light rain over central IL Friday night before
ending. Highs Thursday should be in the mid 50s to around 60,
cooling to the low to mid 40s over the IL river valley to the mid to
upper 50s in southeast IL.
High pressure will build into the Midwest region on Saturday for a
good chance for dry conditions, although GFS is quicker returning
moisture back into central IL and perhaps some precipitation will
return Saturday night into Sunday if this turns out. Chance for
precipitation with this next system looks to linger through Monday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1150 AM CST MON NOV 23 2015
Main aviation forecast concern continues to be potential for fog
development tonight as high pressure slides overhead and winds go
light/variable. Several factors point to at least patchy fog,
including nearly calm winds after sunset and increasing boundary
layer moisture due to snow melt. However, the possible fly-in-
the-ointment will be increasing high clouds currently seen on
visible satellite imagery streaming from the Dakotas into Iowa.
All models suggest these clouds will spread into Illinois late
this afternoon then persist through much of the night. Whether
they will be thick enough to limit radiational cooling and prevent
widespread fog is still in question. Several models such as the
NAM and GFS indicate little or no restriction to visby tonight,
while the HRRR is showing fog developing from mid-evening through
the overnight hours. At this point, will continue to feature
visbys down to around 3SM tonight where snow cover exists at the
I-74 terminals, but will maintain unrestricted visbys at both KSPI
and KDEC.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Onton
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1150 AM CST MON NOV 23 2015
.UPDATE...
ISSUED AT 950 AM CST MON NOV 23 2015
High pressure over the Deep South is providing a mild southwesterly
flow across central Illinois this morning. Thanks to abundant
sunshine, 15z/9am temperatures have already risen into the upper
30s and lower 40s across areas without a snow cover. Further north
over the deeper snow field, readings remain in the lower 30s
along/north of I-74. With only a few high/thin clouds expected to
stream into the area this afternoon, am expecting nearly full
sunshine and continued southwesterly winds. Based on current rate
of temp rise, have adjusted afternoon highs up a few degrees
across the southern two-thirds of the KILX CWA. Highs will range
from the upper 30s from Galesburg to Lacon...to around 50 degrees
along/southwest of a Jacksonville to Flora line.
&&
.SHORT TERM...(Today)
ISSUED AT 330 AM CST MON NOV 23 2015
A weak sfc trough will move through the CWA this morning, switching
southerly winds to westerly. Pressure gradient is currently tighter
ahead of this trough so winds this morning will be higher than this
afternoon, after the trough passes through and sfc ridging begins to
build into the area. Satellite trends indicate lots of clear skies
over the area for the day. Will see some warmer temps today, which
will melt some of the snow, but without any good waa on the sfc and
still fairly good snow pack in the north and northeast, the warmer
temps will be limited to mostly areas south of I-74. Temps over the
snow pack should still be above freezing, but overall below normal
temps expected today.
.LONG TERM...(Tonight through Sunday)
ISSUED AT 330 AM CST MON NOV 23 2015
Surface high pressure ridge settling into the southeast states
tonight and ridging nw into central IL will bring lighter winds to
the area tonight. These lighter winds along with boundary layer
moisture from snow melt will likely develop patchy fog over snow
pack of northern CWA later tonight into mid morning Tue. Models
continue to show streaks of mid/high clouds affecting central and
especially ne CWA tonight with weak upper level disturbances in wnw
flow. Main over level trof and short wave energy will be ne of IL
over the Great Lakes region where more cloud cover expected. Lows
tonight range from lower 20s north of Peoria to upper 20s sw CWA.
00Z models continue to show upper level ridge building into IL and
the ohio river valley Tue/Wed. Meanwhile surface high pressure
strengths as it moves into the mid Atlantic states and New England
Tue night into Wed. Increasing pressure gradient over IL Tue/Wed to
bring breezier south winds along with milder temperatures by Wed.
Highs Tue range from lower 40s from I-74 ne where lingering snow
pack to lower 50s sw CWA. Southeast winds of 8-15 mph on Tuesday.
Added patchy fog to northern CWA overnight Tue night until mid
morning Wed where more moisture from snow melt. Lows Tue night in
the low to mid 30s, with upper 30s from Springfield and Jacksonville
sw.
Strong cutoff upper level low/trof digging into northern CA by
12Z/Wed and moving into the central Rockies on Thanksgiving Day.
Increasing WAA and moisture well ahead of this storm system
possibly getting rain showers into the IL river valley later Wed and
Wed evening. Shower chances increase from nw to se overnight Wed
night into Thursday. Southeast IL likely to stay dry Wed night and
into Thu. Milder highs Wed near 50F from I-74 ne to mid 50s sw CWA
and in southeast IL. Highs Thu in the upper 50s to near 60F. Highest
chances of rain appears to be over the IL river valley Thu and
across the area Thu night and east of the IL river Friday. Better
chance of isolated thunderstorms appears to be sw of central IL Thu
and Thu night. But heavier rains of 1-1.5 inches with locally higher
amounts before diminishing from nw to se during Friday night. Could
see a mix of light snow with the light rain over central IL Friday
night especially overnight before ending. Highs Fri range from low
to mid 40s over IL river valley to the mid to upper 50s in southeast
IL.
High pressure builds into the Great Lakes region on Saturday and
Saturday night bringing cooler temperatures to IL along with drier
conditions. Lingered slight chances of light rain/snow over far
southern 6 counties closer to cold front pressing southward into the
TN river valley. GFS is quicker returning moisture back into central
IL Sunday while ECMWF model waits until Sunday night to bring back
precipitation. Will stay close to superblend pops for now that far
out.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1150 AM CST MON NOV 23 2015
Main aviation forecast concern continues to be potential for fog
development tonight as high pressure slides overhead and winds go
light/variable. Several factors point to at least patchy fog,
including nearly calm winds after sunset and increasing boundary
layer moisture due to snow melt. However, the possible fly-in-
the-ointment will be increasing high clouds currently seen on
visible satellite imagery streaming from the Dakotas into Iowa.
All models suggest these clouds will spread into Illinois late
this afternoon then persist through much of the night. Whether
they will be thick enough to limit radiational cooling and prevent
widespread fog is still in question. Several models such as the
NAM and GFS indicate little or no restriction to visby tonight,
while the HRRR is showing fog developing from mid-evening through
the overnight hours. At this point, will continue to feature
visbys down to around 3SM tonight where snow cover exists at the
I-74 terminals, but will maintain unrestricted visbys at both KSPI
and KDEC.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Auten
LONG TERM...07
AVIATION...Barnes
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1220 PM EST MON NOV 23 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 450 AM EST MON NOV 23 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A TROF EXTENDING S THRU
THE GREAT LAKES REGION. SHEARED OUT SHORTWAVE/LEFT EXIT OF 120+KT
UPPER JET EXTENDING FROM SASKATCHEWAN INTO THE UPPER MISSISSIPPI
VALLEY HAS GENERATED SOME AREAS OF -SN INTO WRN UPPER MI OVERNIGHT.
MODELS OVER THE LAST DAY OF RUNS CORRECTLY TRENDED LIGHTER WITH THIS
PCPN AS SNOW THAT HAS OCCURRED HAS BEEN VERY LIGHT WITH NOT MUCH
MORE THAN A DUSTING OF ACCUMULATION WHERE SNOW HAS FALLEN PER
WEBCAMS. TO THE E...JUST AS SOME HIGH RES MODELS WERE INDICATING 24
HRS AGO...THE REGIONAL CANADIAN IN PARTICULAR...A BURST OF HVY SNOW
MOVED N OFF NRN LAKE MI INTO PARTS OF THE ERN U.P. OVER THE LAST
SEVERAL HRS. IT APPEARS THE EXTREME SE CORNER OF LUCE COUNTY
PROBABLY SAW A VERY BRIEF PERIOD OF MDT TO HVY SNOW AROUND 06Z. THAT
AREA OF MDT/HVY SNOW HAS SHIFTED E INTO THE STRAITS VCNTY SINCE
THEN.
THERE IS STILL SOME CONCERN FOR LAKE ENHANCED SNOW OFF NRN LAKE MI
TO SHIFT/REFORM BACK TO THE W TODAY. ON THE HIGH EXTREME IS THE
REGIONAL CANADIAN WHICH GENERATES 0.3 INCHES OF QPF IN THE FAR SE
CORNER OF LUCE COUNTY BTWN 15Z AND 00Z. SINCE THE MAJORITY OF AVBL
HIGH RES GUIDANCE...INCLUDING THE HIGH RES CANADIAN...KEEPS THE BULK
OF REDEVELOPING LAKE ENHANCED SNOW JUST E OF LUCE COUNTY...WILL KEEP
SNOW AMOUNTS UNDER ADVY CRITERIA WITH PERHAPS 1.5-2 INCHES TO THE SE
OF KERY. ELSEWHERE....PATCHY -SN MOVING ACROSS WRN UPPER MI ATTM
SHOULD DISSIPATE OVER THE NEXT SEVERAL HRS AS IT SHIFTS E AND HAS TO
OVERCOME INITIAL DRY LOWER LEVEL AIR. THEN...A SFC LOW PRES TROF
WILL SWING INTO WRN UPPER MI LATE MORNING/AFTN...BRINGING A WIND
SHIFT TO THE W TO NW. EXPECT -SHSN TO ACCOMPANY THE TROF AS OVERLAKE
INSTABILITY WITH 850MB TEMPS AROUND -7C WILL BE MORE THAN SUFFICIENT
TO GENERATE -SHSN ALONG THE TROF/CONVERGENCE ZONE AS IT CROSSES WRN
LAKE SUPERIOR. THIS WILL THEN TRANSITION TO SCT LAKE EFFECT
-SHSN INTO TONIGHT FOR AREAS FAVORED BY NW WINDS AS 850MB TEMPS DROP
A DEGREE OR TWO C. INITIALLY...INVERSION IS UP AROUND 7KFT THIS
EVENING...BUT FALLS TO AROUND 4KFT W OVERNIGHT AND TO AROUND 5KFT E
LATE. DESPITE THE DECENTLY HIGH INVERSION HEIGHTS...SNOW
ACCUMULATIONS WILL BE LIMITED DUE TO THE DGZ BEING ABOVE THE
CONVECTIVE LAYER. AT THIS POINT...EXPECT ACCUMULATIONS MOSTLY UNDER
1 INCH...BUT IF ANY RELATIVELY STATIONARY BANDS SET UP...THERE
CERTAINLY COULD BE ISOLATED 2-3 INCH AMOUNTS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 422 AM EST MON NOV 23 2015
...RAIN CHANGING TO SNOW WED NIGHT INTO THANKSGIVING DAY WITH
ACCUMULATING SNOW POSSIBLE INTO THU NIGHT...
IN LARGER SCALE...DEEP TROUGH OVER EASTERN CONUS SLIDES TO EASTERN
CANADA ON TUE WHILE SPLIT FLOW TROUGHING DEVELOPS WESTERN CANADA TO
WESTERN CONUS. 1000-850MB TROUGH FORMING ON TUE OVER ROCKIES AND
ADJACENT PLAINS AND LOW-LEVEL HIGH PRESSURE SETTLING TO SOUTHEAST
CONUS WILL ALLOW S/SE WINDS AT SFC TO BRING INCREASING MOISTURE OFF
THE GULF OF MEXICO TOWARD THE MIDDLE MISSISSIPPI RIVER VALLEY. WILL
STAY DRY OVER UPR LAKES ON TUE BUT LATE TUE NIGHT INTO WED MORNING
SOUNDINGS SHOW INCREASING MOISTURE BLO H9 INTO UPPER GREAT LAKES.
IF THERE IS ANY PRECIP AROUND ON WED MORNING...IT LIKELY WOULD TAKE
FORM OF DZ/FZDZ DEPENDING ON SFC TEMPS. BEST CHANCE FOR LIGHT ICING
WOULD BE OVER INTERIOR CNTRL CWA FM IRON/DICKINSON INTO BARAGA AND
WESTERN MARQUETTE COUNTY. MODELS SOMETIMES ARE TOO OVERDONE ON THIS
TYPE OF LOW-LEVEL MOISTENING BUT IN THIS CASE THERE IS DECENT SNOW
PACK JUST TO THE SOUTH SO THAT MAY HELP THE EXPANSION OF LOW-LEVEL
MOISTURE.
LATER ON WEDNESDAY DEEPER MOISTURE AND LARGER SCALE FORCING INCREASE
STEADILY AHEAD OF SHORTWAVE TROUGH SLIDING OVER MANTIOBA AND
NORTHERN ONTARIO. LOW-LEVEL THETA-E ADVECTION INCREASES BRIEFLY
BEFORE BEING SHUNTED TO THE SOUTH AND EAST ON WED NIGHT. SHOULD SEE
LIGHT RAIN BECOME MORE WIDESPREAD...BUT WITHOUT MUCH OF STRONG
MOISTURE TAP AHEAD OF THE TROUGH WITH THE NORTHERN STREAM SHORTWAVE
TROUGH...RAINFALL AMOUNTS SHOULD BE LIGHT. COOLER AIR WITH H85 TEMPS
DOWN BLO -2C SLIDES IN AFTER MIDNIGHT WED NIGHT OVER THE WEST AND
THAT SHOULD TURN ANY LINGERING RAIN TO SNOW. GFS SOUNDINGS AND H85-
H7 RH FIELDS FM THE ECMWF INDICATE MID-LEVEL DRYING MAY LEAD TO
CHANCES OF FREEZING DRIZZLE OR DRIZZLE INSTEAD OF SNOW LATE WED
NIGHT INTO THANKSGIVING MORNING WITH MOIST LAYER AT TEMPS BLO 0C BUT
MUCH WARMER THAN -10C. UPSLOPE FLOW OFF LK SUPERIOR WOULD ALSO AID
IN LOW-LEVEL LIFT AND MAYBE LEAD TO GREATER CHANCES OF DRIZZLE FOR
WEST AND NCNTRL UPR MICHIGAN. ADDED MENTION OF DZ/FZDZ IN THE GRIDS
FOR THESE AREAS.
ATTN LATER ON THANKSGIVING TURNS TO WAVE OF LOW PRESSURE THAT RIDES
NORTHEAST ALONG THE TROUGH OVER THE UPR GREAT LAKES. 00Z ECMWF
TRENDED FARTHER WEST WITH THE WAVE WHILE THE GFS TRENDED FARTHER
EAST. IF THE ECMWF IS CORRECT SWATH OF MODERATE PRECIP WOULD LIFT
BACK OVER AT LEAST THE SOUTH AND EAST CWA THANKSGIVING AFTN INTO
THU NIGHT. SINCE THE INITIAL TROUGH/COLD FRONT IS THROUGH MOST CWA
PTYPE WOULD MOSTLY BE SNOW...EXCEPT OVER FAR SCNTRL WHERE WARM AIR
LINGERS AS EVEN ECMWF SHOWS H85 TEMPS AT LEAST +1C WHEN HEAVIER QPF
IS FORECAST TO MOVE THROUGH. SFC TEMPS STILL MID 30S AS WELL SO NO
RISK OF ANY FREEZING PRECIP EITHER. JUST INLAND OVER SOUTH CENTRAL
AND OVER MOST OF THE EASTERN CWA /N WINDS LEADING TO OFFSHORE WINDS
AT ESC AND ISQ/ COULD SEE SEVERAL INCHES OF WET SNOW WITH THE ECMWF
SOLN AS 12 HR QPF BTWN 18Z THU AND 06Z FRI IS AT LEAST 0.5 IF NOT UP
TO 0.75 INCH. MEANWHILE...LATEST GFS BARELY IS OVER 0.25 INCHES FOR
THAT TIME FRAME. GEM IS MORE LIKE THE ECMWF WITH TOTAL QPF...BUT MUCH
WARMER AND WOULD RESULT IN MOSTLY RAIN FOR THOSE AREAS. WPC PREFERRED
CONSENSUS OF GFS/ECMWF/GEM. WILL CONTINUE TO MENTION THE RAIN TO SNOW
AND SOME ACCUMULATING SNOW IN THE HWO...BUT CANNOT PLAY UP THE SNOW
TOO MUCH OR GET TOO SPECIFIC YET GIVEN THE UNCERTAINTIES THAT REMAIN.
BEHIND THIS SYSTEM...TURNS COLD ENOUGH FOR LAKE EFFECT SNOW SHOWERS
OFF LK SUPERIOR FRI INTO FRI NIGHT. ON FRI...AREAS FAVORED BY N
WINDS MAY SEE SOME SNOW FOR A CHANGE...THEN WOULD BE MAINLY NW FLOW
AREAS FRI NIGHT. DRY LOW-LEVEL AIRMASS WITH STRONG HIGH BUILDING IN
SHOULD LIMIT EXTENT OF LES. BASED ON CURRENT MODEL SOLUTIONS IT IS
DOUBTFUL AMOUNTS WOULD REACH ADVY LEVELS FRI-FRI NIGHT. SLIGHT
WARMING TREND WITH GENERALLY DRY WEATHER IS EXPECTED FOR NEXT
WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1220 PM EST MON NOV 23 2015
WITH THE PASSAGE OF A SFC TROF...LAKE EFFECT -SHSN WILL DEVELOP FOR
AREAS FAVORED BY NW WINDS THIS AFTN AND TONIGHT. FOR
KCMX/KIWD...THIS MEANS MVFR CONDITIONS SHOULD PREVAIL THRU THE FCST
PERIOD. AT KSAW...VFR CONDITIONS SHOULD CONTINUE INTO THE MID AFTN
WITH A DOWNSLOPE WESTERLY WIND. MVFR CONDITIONS SHOULD THEN DEVELOP
AT KSAW LATE AFTN AND CONTINUE THRU TUE MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 AM EST MON NOV 23 2015
NO GALES ARE EXPECTED ON LAKE SUPERIOR THRU THE END OF THE WEEK.
PREVIOUSLY...THERE WERE INDICATIONS OF A GALE EVENT THU NIGHT/FRI
AFTER A COLD FRONT PASSES. HOWEVER...IT NOW APPEARS THAT THE FRONT
WILL BE WEAKER SO THAT WINDS WILL REMAIN BLO GALE FORCE. LIGHTEST
WINDS THIS WEEK WILL OCCUR TUE AS A HIGH PRES RIDGE QUICKLY SHIFTS
ACROSS THE UPPER GREAT LAKES. STRONGEST WINDS THIS WEEK WILL OCCUR
LATE TUE NIGHT/WED OVER THE E HALF OF LAKE SUPERIOR IN THE SOUTHERLY
FLOW AHEAD OF THE AFOREMENTIONED COLD FRONT AND THEN LATE THU/FRI
AFTER THE FRONT PASSES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
240 PM CST MON NOV 23 2015
.SYNOPSIS...
ISSUED AT 239 PM CST MON NOV 23 2015
BROAD NWRLY FLOW ALOFT FORMED BY A SLOWLY EXITING LONG WAVE TROUGH
ACROSS THE EASTERN STATES AND BROAD...WEAK RIDGING IN THE WEST. OFF
THE BC COAST...A DEVELOPING LONG WAVE TROUGH WHICH WILL BE SLIDING
EWD TO THE WEST COAST. LEAD SHORT WAVE/PV ANOMALY MOVING ONTO THE
CENTRAL CA COAST CURRENTLY PRODUCING BAROCLINIC LEAF OVER NV. CLOSER
TO HOME...SATELLITE IMAGERY SHOWING SNOW FIELD ACROSS PORTIONS OF NC
NEB CONTINUING TO ERRODE SLOWLY AS TEMPS WARM QUICKLY UNDER MOSTLY
FULL SUNSHINE AND DESPITE LIGHT WIND.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 239 PM CST MON NOV 23 2015
BIGGEST CONCERN OVERNIGHT IS THE POTENTIAL FOR FOG/LOW CLOUDS IN
PORTIONS OF THE NC FCST AREA. NAM/SREF HAVE BEEN CONSISTENT AT
SUGGESTING THIS AND NAM BUFR SOUNDINGS SHOW A LAYER OF TRAPPED COLD
AIR FROM THE SFC TO ABOUT 600 FT. NAM HAS ISSUES WITH LOWER
LAYER IN AND NEAR SNOW COVER...BUT COULD STILL BE SUGGESTING A
REALISTIC POTENTIAL. SREF VSBY PROBS SHOW GOOD POTENTIAL FOR
REDUCED VSBY IN THE 06-12Z TUES TIME FRAME. MEANWHILE THE RAP BUFR
SOUNDINGS ARE NOT SHOWING THIS AND GFS LAMP GUIDANCE HAS BACKED
OFF. FROM AN OBSERVATIONAL PERSPECTIVE LIGHT SOUTHEASTERLY WINDS
OVERNIGHT IN CONCERT WITH ANY RESIDUAL MOISTURE FROM MELTING SNOW
WOULD SUGGEST NAM COULD BE ON TO SOMETHING. HAVE ADDED PATCHY FOG
TO THE FCST THOUGH WILL HAVE TO MONITOR FOR MORE STRONGER WORDING
IF DEVELOPMENT DOES OCCUR.
PREVIOUSLY MENTIONED LEAD SHORT WAVE WILL PIVOT NEWD INTO THE HIGH
PLAINS DURING THE DAY TUES. ASSOCIATED HEIGHT FALLS WILL SERVE TO
KICK THE PREVIOUSLY DEVELOPED SFC TROUGH EWD DURING THE DAY
WHICH...BECAUSE OF DRY LOWER LEVELS...SHOULD ONLY RESULT IN A WIND
SHIFT FROM SERLY TO SRLY OR SWRLY BEHIND SFC TROUGH. WEAK LARGE
SCALE LIFT WILL TEMPER HIGHS A BIT TMRW...BUT BY LATE IN THE DAY
SUBSIDENCE BECOMES RE-ESTABLISHED AND WOULD EXPECT TEMPS TO RETURN
TO ABOVE NORMAL VALUES AGAIN. HAVE TRENDED FCST TWD THE HIGH END OF
THE ENVELOPE OF POSSIBILITIES AS A RESULT AND ALSO BECAUSE TEMPS
HAVE WARMED ABOVE EXPECTTED LEVELS THE LAST TWO DAYS. TEMPS WILL
CONTINUE TO BE HELD DOWN WHERE SNOW COVER STILL REMAINS IN NC NEB
AND ALSO IF CLOUDS DO FORM THEY WILL INHIBIT INSOLATION DURING THE
MORNING HOURS. OTHERWISE LITTLE IN THE WAY OF FCST CONCERNS FOR
TUES.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 239 PM CST MON NOV 23 2015
SOUTHERLY LOW LEVEL FLOW WILL BEGIN TO DRAW MOISTURE NORTHWARD INTO
THE CENTRAL PLAINS TUESDAY NIGHT. MODELS INDICATE THAT STRATUS
WILL DEVELOP AND SPREAD NORTHWARD TUESDAY NIGHT. RIGHT NOW IT
APPEARS THAT MOST OF THAT WILL BE DIRECTED TOWARD CENTRAL AND EASTERN
NEBRASKA...BUT MAY CLIP THE VERY FAR EASTERN PORTIONS OF THE AREA.
HAVE INTRODUCED PATCHY FOG INTO THE SRN ZONES LATE TUESDAY NIGHT
INTO EARLY WEDNESDAY MORNING.
AN ARCTIC COLD FRONT WILL SWEEP SOUTH THROUGH THE AREA WEDNESDAY.
AT THE SAME TIME A LEAD WAVE WILL BEGIN TO EJECT EASTWARD FROM THE
WESTERN CONUS UPPER LOW. EXPECT FALLING TEMPERATURES WEDNESDAY
AFTERNOON AS THE COLD FRONT PASSES AS WELL AS AN INCREASE IN MID
AND UPPER LEVEL CLOUDS. MAY NOT SEE THE HIGHER CLOUDS
HOWEVER...AS LOW STRATUS CLOUDS WILL QUICKLY INCREASE/DEVELOP
SOUTHWARD BEHIND THE FRONT.
ARCTIC AIR WILL BE FILTERING SOUTH THROUGH THE AREA WEDNESDAY NIGHT
BEHIND THE COLD FRONT. A PERIOD OF LIGHT DRIZZLE AND FREEZING
DRIZZLE DURING THE EVENING TO FREEZING DRIZZLE/SNOW AFTER
MIDNIGHT. NAM BUFKIT SOUNDING INDICATE A FREEZING DRIZZLE
SOUNDING...WHILE THE GFS KEEPS THE LOWEST LEVELS DRIER. WITH
CONSIDERABLE DRY AIR ALOFT NOT SURE WE WILL SEE MUCH SNOW. MAY BE
MORE FREEZING DRIZZLE.
THE LEAD WAVE WILL CROSS THE CENTRAL AND SOUTHERN PLAINS
THANKSGIVING. MOST OF THE PRECIPITATION WILL REMAIN EAST AND
SOUTHEAST OF THE IMMEDIATE AREA...BUT SOME VERY LIGHT SNOW IS
POSSIBLE WITH ACCUMULATIONS EXPECTED TO REMAIN A DUSTING. NOT MUCH
CHANGE TO HIGHS WITH MID TO UPPER 20S FCST. NORTH TO NORTHEAST
WINDS 10 TO 20 MPH HOWEVER WILL GIVE WIND CHILLS IN THE TEENS.
FOR THE WEEKEND...PARTICULARLY SATURDAY INTO MONDAY...OPERATIONAL
MODELS EJECT THE LARGE UPPER LEVEL TROUGH EASTWARD INTO THE
CENTRAL PLAINS. PLENTY OF QUESTIONS REGARDING TIMING. FOR NOW
WILL CARRY A SLIGHT TO LOW CHANCE POP FOR SNOW SATURDAY INTO
MONDAY. OTHERWISE CONTINUED COLD WITH BELOW NORMAL TEMPERATURES
IN THE MID 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1130 AM CST MON NOV 23 2015
VFR CONDITIONS THROUGH THE FIRST PART OF THE FCST BUT SOME CONCERN
FOR VSBY RESTRICTIONS AND IFR CIGS LATE TONIGHT AT KVTN.
TRANSITORY RIDGING ALOFT WILL MOVE ACROSS THE PLAINS AS LONG WAVE
TROUGH OVER THE EAST MOVES OUT. THE RESULT WILL BE A MORE ZONAL
FLOW ALOFT WHICH WILL SERVE TO DEVELOP LOW PRESSURE ALONG THE LEE
OF THE ROCKIES. SFC RESULT IS A WEAK FRONTAL BOUNDARY RETREATING
EWD AS WARM AIR DESCENDS FROM THE WEST. SOME MID/HIGH CLOUDS
RESULTING FROM THE ISENTROPIC LIFT THIS AFTERNOON PUSHING EWD.
THIS WILL SETUP A FAVORABLE PATTERN TONIGHT FOR LOW CLOUDS AND
FOG...WHICH THE NAM AND THE 23.09Z SREF PICK UP ON. SKEPTICAL OF
THE NAM DUE ITS TENDENCY TO NOT MIX THE LOW LAYERS ENOUGH DURING
THE DAY AND DEVELOP TOO MUCH COLD AIR NEAR THE SFC AT NIGHT.
BUT...SINCE THIS IS A PATTERN FAVORABLE HAVE TRENDED THE FCST FOR
KVTN IN THAT MANNER THOUGH CONFIDENCE IS ONLY MEDIUM AT THIS
POINT. NO RESTRICTIONS IN THE FCST AT THIS TIME FOR KLBF.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STOPPKOTTE
SHORT TERM...STOPPKOTTE
LONG TERM...ROBERG
AVIATION...STOPPKOTTE
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1259 PM CST MON NOV 23 2015
.UPDATE...
ISSUED AT 1256 PM CST MON NOV 23 2015
FOR THE EARLY AFTERNOON UPDATE BUMPED TEMPERATURES UP A FEW
DEGREES MOST AREAS. DID TEMPER HIGHS A LITTLE OVER THE FAR
SOUTHWEST WHERE PERSISTENT MID AND HIGH LEVEL CLOUDS REMAIN.
OTHERWISE NO SIGNIFICANT CHANGES TO THE GOING FORECAST.
UPDATE ISSUED AT 959 AM CST MON NOV 23 2015
HIGH PRESSURE WILL CONTINUE TO MOVE EAST ACROSS THE FORECAST AREA
TODAY. HIGH LEVEL CLOUDS WILL CONTINUE TO INCREASE FROM WEST TO
EAST. SOME MID LEVEL WARM ADVECTION CLOUDINESS SPREADING FROM
EASTERN MONTANA INTO SOUTHWEST NORTH DAKOTA TODAY COULD PRODUCE A
FEW FLURRIES...BUT NOT WORTH A MENTION AT THIS TIME. ADJUSTED
CLOUDS HIGHER WEST AND LOWER EAST THROUGH THE MORNING.
TEMPERATURES LOOK REASONABLE AND NO ADJUSTMENTS OTHER THAN
POPULATING THE LATEST OBSERVATIONS.
UPDATE ISSUED AT 635 AM CST MON NOV 23 2015
NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE CYCLE OTHER THAN
BLENDING RECENT OBSERVATIONS WITH SHORT TERM MODEL GUIDANCE. RADAR
ECHOES IN NORTHEASTERN MT REFLECT AN INCREASE IN MIDDLE- AND HIGH-
LEVEL CLOUDS AND NOT PRECIPITATION DUE TO A DRY LOWER ATMOSPHERE.
THAT SCENARIO IS WELL-REFLECTED BY RECENT HRRR ITERATIONS AND THUS
THE DRY FORECAST FOR TODAY APPEARS TO BE WELL IN HAND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 337 AM CST MON NOV 23 2015
QUIET WEATHER HIGHLIGHTS THE SHORT TERM PERIOD.
CURRENTLY...THE STRONG LOW PRESSURE SYSTEM ASSOCIATED WITH
YESTERDAY`S WINDY CONDITIONS WAS CENTERED OVER THE BORDER OF
MANITOBA/ONTARIO/MINNESOTA. A WEAK HIGH PRESSURE AXIS EXTENDED FROM
SOUTHERN ALBERTA SOUTHEASTWARD INTO EASTERN MONTANA AND THE WESTERN
DAKOTAS...WITH BROAD LOW PRESSURE DEVELOPING IN THE LEE OF THE
ROCKIES.
TODAY THE STRONG LOW PRESSURE SYSTEM IS FORECAST TO MOVE EAST
TOWARDS THE GREAT LAKES AND HUDSON BAY...AND THE SURFACE HIGH
PRESSURE RIDGE AXIS MOVES EASTWARD INTO THE CENTRAL AND EASTERN
DAKOTAS AS AN UPPER LEVEL RIDGE BUILDS/EXPANDS FROM THE ROCKIES INTO
THE WESTERN PLAINS. MAINLY PARTLY CLOUDY SKIES TODAY WITH
MIDDLE/HIGH CLOUDS MOVING EAST INTO NORTH DAKOTA. WARMER AIR IN
SOUTHWESTERN NORTH DAKOTA WITH HIGHS IN THE LOWER 40S...WITH COOLER
AIR TO THE NORTHEAST WITH HIGHS IN THE MID TO UPPER 30S.
TONIGHT THE BROAD UPPER LEVEL RIDGE MIGRATES EASTWARD AND THE FLOW
OVER THE ROCKIES BECOMES SOUTHWESTERLY ALOFT. IN RESPONSE...BROAD
SURFACE LOW PRESSURE DEVELOPS OVER THE ROCKIES AND FRONT RANGE...AND
A LONG BROAD FETCH OF SOUTHERLY SURFACE WINDS DEVELOPS FROM THE
SOUTHERN PLAINS NORTHWARD INTO THE NORTHERN PLAINS. A LOW LEVEL JET
DEVELOPS...AND THIS WILL ALLOW LOW LEVEL MOISTURE TO STREAM
NORTHWARD INTO SOUTH CENTRAL CANADA. LOOK FOR INCREASING LOW CLOUDS
WITH SOUTHEASTERLY SURFACE WINDS...AND INCREASING MID LEVEL CLOUDS
MOVING IN FROM THE WEST/SOUTHWEST. LOW TEMPERATURES ARE EXPECTED TO
BE IN THE 20S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 337 AM CST MON NOV 23 2015
THE FOCUS IN THE LONG TERM IS ON LIGHT SNOW POTENTIAL CENTERED ON
WEDNESDAY. WE ARE BECOMING MORE CONFIDENT THAT ACCUMULATIONS WILL
BE RELATIVELY LOW WITH THIS EVENT...POTENTIALLY LIMITING IMPACTS.
THE 00 UTC MODEL SUITE WAS IN RELATIVELY GOOD AGREEMENT IN SHOWING
LIGHT SNOW DEVELOPING IN WESTERN ND BY EARLY WEDNESDAY MORNING AND
SPREADING EASTWARD DURING THE DAY. THE MULTI-MODEL CONSENSUS CALLS
FOR LIQUID-EQUIVALENT MOISTURE VALUES OF 0.05 TO 0.15 INCHES /MOST
IN FAR SOUTHWESTERN ND/...WHICH SHOULD CONTRIBUTE TO SNOW AMOUNTS
RANGING FROM LESS THAN ONE-HALF INCH TO THE NORTH AND EAST OF THE
MISSOURI RIVER...TO 1 TO 2 INCHES SOUTH AND WEST OF THE MISSOURI
RIVER. OUR OFFICIAL FORECAST PRODUCED 3 INCH SNOW TOTALS ONLY IN
EXTREME SOUTHWESTERN ND...BOWMAN AND SLOPE COUNTIES...WEDNESDAY
THROUGH WEDNESDAY NIGHT.
THE SNOW WILL BE GENERATED IN A POST-FRONTAL ENVIRONMENT...DRIVEN
MAINLY BY DYNAMICS ASSOCIATED WITH A SHORTWAVE TROUGH EMBEDDED IN
THE NORTHERN STREAM OF A SPLIT FLOW. THE 03 UTC SREF LINGERED THE
SNOW LONGER THAN THE 00 UTC DETERMINISTIC GUIDANCE...SO A BIT OF
UNCERTAINTY REMAINS...BUT IN GENERAL GUIDANCE CONTINUED TO SUGGEST
THAT THE PRIMARY VERTICAL MOTION ASSOCIATED WITH THE 500-MB LOW IN
THE GREAT BASIN WILL REMAIN DISPLACED SOUTH OF ND. IF THAT IS THE
CASE...THANKSGIVING DAY MAY END UP COLD...BUT DRY IN MOST AREAS.
ONE OTHER ISSUE WE WILL NEED TO CONSIDER IS WHETHER FOG DEVELOPS
TUESDAY NIGHT...AND WHETHER LINGERING WARM AND DRY AIR ALOFT IS
CAPABLE OF PRODUCING ANY LIGHT FREEZING RAIN OR LIGHT FREEZING
DRIZZLE TUESDAY NIGHT INTO WEDNESDAY MORNING. FORECAST SOUNDINGS
ARE NOT PARTICULARLY SUGGESTIVE OF THAT POTENTIAL THOUGH...SO WE
ARE NOT MESSAGING THAT RISK AT THIS POINT.
A REX BLOCK WILL DEVELOP ALOFT OVER THE WESTERN UNITED STATES BY
NEXT WEEKEND AS THE GREAT BASIN LOW GETS PINCHED OFF TO THE SOUTH
OF A DEVELOPING 500-MB RIDGE OVER WESTERN CANADA. THIS SCENARIO IS
EXPECTED TO GENERATE A WARMING TREND AND MAINLY DRY WEATHER ACROSS
THE AREA NEXT WEEKEND...THOUGH THE 00 UTC GFS /AND THE 00 UTC GFS
ALONE/ DOES SUGGEST SOME SNOW POTENTIAL RETURNING NEXT SUNDAY WHEN
IT BREAKS THE BLOCK DOWN AND KICKS THE REMNANT LOW ALOFT EASTWARD
FURTHER NORTH THAN THE REST OF THE 00 UTC MODEL GUIDANCE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1256 PM CST MON NOV 23 2015
A BAND OF MID TO HIGH LEVEL CLOUDS WILL MOVE ACROSS NORTH DAKOTA
MONDAY AFTERNOON AND EVENING...FROM THE SOUTHWEST TO NORTHEAST. AS
WE APPROACH THE OVERNIGHT HOURS...LOWER LEVEL MOISTURE WILL
INCREASE...BRINGING MVFR CEILINGS TO KDIK...AND POSSIBLY TO ALL
OTHER SITES. MORE UNCERTAINTY REGARDING LOWER CEILINGS EXIST ACROSS
THESE OTHER SITES...SO MODEL TRENDS WILL HAVE TO BE MONITORED
CLOSELY. FOR NOW WILL JUST KEEP SCATTERED LOWER CLOUDS IN THE
FORECAST FOR KISN/KMOT/KBIS/KJMS. VARIABLE LIGHT WINDS WILL PREVAIL
ACROSS ALL SITES THROUGH THE PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JV
LONG TERM...CJS
AVIATION...ZH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1005 AM CST MON NOV 23 2015
.UPDATE...
ISSUED AT 959 AM CST MON NOV 23 2015
HIGH PRESSURE WILL CONTINUE TO MOVE EAST ACROSS THE FORECAST AREA
TODAY. HIGH LEVEL CLOUDS WILL CONTINUE TO INCREASE FROM WEST TO
EAST. SOME MID LEVEL WARM ADVECTION CLOUDINESS SPREADING FROM
EASTERN MONTANA INTO SOUTHWEST NORTH DAKOTA TODAY COULD PRODUCE A
FEW FLURRIES...BUT NOT WORTH A MENTION AT THIS TIME. ADJUSTED
CLOUDS HIGHER WEST AND LOWER EAST THROUGH THE MORNING.
TEMPERATURES LOOK REASONABLE AND NO ADJUSTMENTS OTHER THAN
POPULATING THE LATEST OBSERVATIONS.
UPDATE ISSUED AT 635 AM CST MON NOV 23 2015
NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE CYCLE OTHER THAN
BLENDING RECENT OBSERVATIONS WITH SHORT TERM MODEL GUIDANCE. RADAR
ECHOES IN NORTHEASTERN MT REFLECT AN INCREASE IN MIDDLE- AND HIGH-
LEVEL CLOUDS AND NOT PRECIPITATION DUE TO A DRY LOWER ATMOSPHERE.
THAT SCENARIO IS WELL-REFLECTED BY RECENT HRRR ITERATIONS AND THUS
THE DRY FORECAST FOR TODAY APPEARS TO BE WELL IN HAND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 337 AM CST MON NOV 23 2015
QUIET WEATHER HIGHLIGHTS THE SHORT TERM PERIOD.
CURRENTLY...THE STRONG LOW PRESSURE SYSTEM ASSOCIATED WITH
YESTERDAY`S WINDY CONDITIONS WAS CENTERED OVER THE BORDER OF
MANITOBA/ONTARIO/MINNESOTA. A WEAK HIGH PRESSURE AXIS EXTENDED FROM
SOUTHERN ALBERTA SOUTHEASTWARD INTO EASTERN MONTANA AND THE WESTERN
DAKOTAS...WITH BROAD LOW PRESSURE DEVELOPING IN THE LEE OF THE
ROCKIES.
TODAY THE STRONG LOW PRESSURE SYSTEM IS FORECAST TO MOVE EAST
TOWARDS THE GREAT LAKES AND HUDSON BAY...AND THE SURFACE HIGH
PRESSURE RIDGE AXIS MOVES EASTWARD INTO THE CENTRAL AND EASTERN
DAKOTAS AS AN UPPER LEVEL RIDGE BUILDS/EXPANDS FROM THE ROCKIES INTO
THE WESTERN PLAINS. MAINLY PARTLY CLOUDY SKIES TODAY WITH
MIDDLE/HIGH CLOUDS MOVING EAST INTO NORTH DAKOTA. WARMER AIR IN
SOUTHWESTERN NORTH DAKOTA WITH HIGHS IN THE LOWER 40S...WITH COOLER
AIR TO THE NORTHEAST WITH HIGHS IN THE MID TO UPPER 30S.
TONIGHT THE BROAD UPPER LEVEL RIDGE MIGRATES EASTWARD AND THE FLOW
OVER THE ROCKIES BECOMES SOUTHWESTERLY ALOFT. IN RESPONSE...BROAD
SURFACE LOW PRESSURE DEVELOPS OVER THE ROCKIES AND FRONT RANGE...AND
A LONG BROAD FETCH OF SOUTHERLY SURFACE WINDS DEVELOPS FROM THE
SOUTHERN PLAINS NORTHWARD INTO THE NORTHERN PLAINS. A LOW LEVEL JET
DEVELOPS...AND THIS WILL ALLOW LOW LEVEL MOISTURE TO STREAM
NORTHWARD INTO SOUTH CENTRAL CANADA. LOOK FOR INCREASING LOW CLOUDS
WITH SOUTHEASTERLY SURFACE WINDS...AND INCREASING MID LEVEL CLOUDS
MOVING IN FROM THE WEST/SOUTHWEST. LOW TEMPERATURES ARE EXPECTED TO
BE IN THE 20S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 337 AM CST MON NOV 23 2015
THE FOCUS IN THE LONG TERM IS ON LIGHT SNOW POTENTIAL CENTERED ON
WEDNESDAY. WE ARE BECOMING MORE CONFIDENT THAT ACCUMULATIONS WILL
BE RELATIVELY LOW WITH THIS EVENT...POTENTIALLY LIMITING IMPACTS.
THE 00 UTC MODEL SUITE WAS IN RELATIVELY GOOD AGREEMENT IN SHOWING
LIGHT SNOW DEVELOPING IN WESTERN ND BY EARLY WEDNESDAY MORNING AND
SPREADING EASTWARD DURING THE DAY. THE MULTI-MODEL CONSENSUS CALLS
FOR LIQUID-EQUIVALENT MOISTURE VALUES OF 0.05 TO 0.15 INCHES /MOST
IN FAR SOUTHWESTERN ND/...WHICH SHOULD CONTRIBUTE TO SNOW AMOUNTS
RANGING FROM LESS THAN ONE-HALF INCH TO THE NORTH AND EAST OF THE
MISSOURI RIVER...TO 1 TO 2 INCHES SOUTH AND WEST OF THE MISSOURI
RIVER. OUR OFFICIAL FORECAST PRODUCED 3 INCH SNOW TOTALS ONLY IN
EXTREME SOUTHWESTERN ND...BOWMAN AND SLOPE COUNTIES...WEDNESDAY
THROUGH WEDNESDAY NIGHT.
THE SNOW WILL BE GENERATED IN A POST-FRONTAL ENVIRONMENT...DRIVEN
MAINLY BY DYNAMICS ASSOCIATED WITH A SHORTWAVE TROUGH EMBEDDED IN
THE NORTHERN STREAM OF A SPLIT FLOW. THE 03 UTC SREF LINGERED THE
SNOW LONGER THAN THE 00 UTC DETERMINISTIC GUIDANCE...SO A BIT OF
UNCERTAINTY REMAINS...BUT IN GENERAL GUIDANCE CONTINUED TO SUGGEST
THAT THE PRIMARY VERTICAL MOTION ASSOCIATED WITH THE 500-MB LOW IN
THE GREAT BASIN WILL REMAIN DISPLACED SOUTH OF ND. IF THAT IS THE
CASE...THANKSGIVING DAY MAY END UP COLD...BUT DRY IN MOST AREAS.
ONE OTHER ISSUE WE WILL NEED TO CONSIDER IS WHETHER FOG DEVELOPS
TUESDAY NIGHT...AND WHETHER LINGERING WARM AND DRY AIR ALOFT IS
CAPABLE OF PRODUCING ANY LIGHT FREEZING RAIN OR LIGHT FREEZING
DRIZZLE TUESDAY NIGHT INTO WEDNESDAY MORNING. FORECAST SOUNDINGS
ARE NOT PARTICULARLY SUGGESTIVE OF THAT POTENTIAL THOUGH...SO WE
ARE NOT MESSAGING THAT RISK AT THIS POINT.
A REX BLOCK WILL DEVELOP ALOFT OVER THE WESTERN UNITED STATES BY
NEXT WEEKEND AS THE GREAT BASIN LOW GETS PINCHED OFF TO THE SOUTH
OF A DEVELOPING 500-MB RIDGE OVER WESTERN CANADA. THIS SCENARIO IS
EXPECTED TO GENERATE A WARMING TREND AND MAINLY DRY WEATHER ACROSS
THE AREA NEXT WEEKEND...THOUGH THE 00 UTC GFS /AND THE 00 UTC GFS
ALONE/ DOES SUGGEST SOME SNOW POTENTIAL RETURNING NEXT SUNDAY WHEN
IT BREAKS THE BLOCK DOWN AND KICKS THE REMNANT LOW ALOFT EASTWARD
FURTHER NORTH THAN THE REST OF THE 00 UTC MODEL GUIDANCE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 959 AM CST MON NOV 23 2015
VFR CONDITIONS EXPECTED UNTIL AROUND 02Z-06Z MONDAY EVENING...WHEN
INCREASING LOW CLOUDS WILL RESULT IN MVFR CIGS AT ALL TAF SITES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...JV
LONG TERM...CJS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
320 PM CST MON NOV 23 2015
.TONIGHT - CONFIDENCE...MEDIUM.
PER WATER VAPOR/RAP LOOP BROAD MID/UPPER LEVEL ANTICYCLONIC FLOW
SHIFTING EASTWARD INTO WI. SFC/850 RIDGE AXES DRAW CLOSER WITH TIME
WHICH RESULTS IN GRADUAL EROSION OF THE LOW LEVEL THERMAL TROUGH SO
THINKING MUCH OF THE CLOUD COVER UPSTREAM ACROSS NRN MN AND NRN WI
WILL NOT MAKE IT INTO OUR AREA PLUS SOME OF THIS IS DIURNALLY DRIVEN
AS WELL. HOWEVER SREF CIG/VSBY PROGS ALONG WITH MET MOS ARE KEYING
ON SOME FOG/STRATUS DEVELOPMENT AS THE NIGHT WEARS ON AND THIS WOULD
MAKE THE MOST SENSE NEAR THE DEEPER SNOWFIELD ACROSS THE SRN CWA AND
IN CLOSER PROXIMITY TO ARRIVING LIGHTER WIND REGIME ASSOC WITH RIDGE
AXIS. VSBL SATELLITE ANIMATION DOES SHOW SOME EROSION OF THE
SNOWPACK FROM THE EDGES AND SOME THINNING FROM WITHIN. LLVL RH
PROGS/GFS MOS AND RAP SOUNDINGS ARE NOT TOO EXCITED ABOUT
STRATUS/FOG DEVELOPMENT AND WITH MAINLY CIRRUS UPSTREAM NOTHING.
HAVE ADDED PATCHY FOG IN THE SOUTHERN CWA AND BOOSTED SKY COVER A
BIT LATER IN THE NIGHT.
.TUESDAY - CONFIDENCE...MEDIUM
SFC RIDGE AXIS SHIFTS EAST. WITH LIGHT WIND REGIME EARLY WITH
SURFACE/850 RIDGE AXIS NEARBY ANY STRATUS/FOG EROSION MAY BE SLOW
UNTIL BETTER SOUTHERLY FLOW SETS UP. THIS RETURN FLOW WILL HELP TO
FURTHER MODIFY THE LOW LEVEL THERMAL PATTERN. HAVE BOOSTED TEMPS TO
ACCOUNT FOR ADDITIONAL EROSION IN SNOWCOVER AND 925 TEMPS INCHING
FURTHER ABOVE 0C ESP DURG THE AFTN WHEN SOUTHERLY FLOW RAMPS UP A
BIT MORE.
.TUESDAY NIGHT THROUGH THURSDAY - FORECAST CONFIDENCE...MEDIUM.
NO SIGNIFICANT CHANGES FOR THIS PERIOD. ZONAL STEERING FLOW
TRANSITIONS TO MORE SOUTHWEST FLOW AS LONG WAVE TROF
PROGRESSES SOUTHEAST ACROSS WESTERN CONUS. NORTHERN PORTION OF TROF
BREAKS AWAY AND BECOMES MORE PROGRESSIVE ACROSS NORTHERN CONUS WHILE
CUTOFF LOW LINGERS OVER WESTERN CONUS. AHEAD OF THIS APPROACHING
TROF...INCREASING SOUTHERLY WINDS IN THE LOW LEVELS WILL GRADUALLY
PULL DEEPER MOISTURE NORTHWARD INTO THE AREA BEGINNING WEDNESDAY.
COLUMN PWAT EXPECTED TO INCREASE TO OVER 1 INCH BY THU AFTN...WHICH
WOULD BE NEAR OR SLIGHTLY ABOVE THE RECORD PWAT FOR NORTHWEST IL PER
SPC SOUNDING CLIMATOLOGY AND STILL IN THE NEIGHBORHOOD OF 3
STANDARD DEVIATIONS FROM NORMAL.
MAIN PERIOD OF RAIN LIKELY TO BE LATER THURSDAY INTO THURSDAY NIGHT
WHEN DEEP MOISTURE WILL BE IN PLACE AND LOW LEVEL JET SURGES INTO
THE TRI-STATE AREA OF SRN WI/NRN IL AND ERN IA. IN ADDITION...RIGHT
ENTRANCE REGION OF UPPER JET PASSES ACROSS THIS SAME AREA DURING
THE PERIOD. OF SHORT TERM GUIDANCE...GFS REMAINS OUTLIER WITH MORE
PROGRESSIVE SOLUTION WITH STRONGEST SYNOPTIC FORCING JUST TO THE
SOUTH OF WI. 18Z NAM...GEH-NH AND ECMWF REMAIN FOCUSED FARTHER
NORTH SO ALONG WITH WPC...WILL LEAN ON THIS CONCENSUS WHICH
INCREASES THE THREAT FOR A PERIOD OF HEAVY RAINFALL ACROSS SRN WI ON
THU/THU NIGHT.
STILL THINKING 1-1.5 INCHES MAY FALL IN A 6 TO 12 HOUR PERIOD. BY
THAT TIME...THINKING THAT CURRENT SNOW COVER WILL BE CUT IN HALF DUE
TO GRADUAL MELTING THE NEXT FEW DAYS. THREAT FOR THICKER FOG AND
RELEASE OF LATENT HEAT OF CONDENSATION BEGINS WED NGT SO EXPECT SNOW
COVER TO BEGIN DECREASING MORE RAPIDLY THEN. GROUND NOT FROZEN AND
REMAINING SNOW SHOULD ABSORB SOME OF THE INITIAL RAIN. HOWEVER WITH
LINGERING SNOW ACROSS FAR SOUTHERN COUNTIES AND PERIOD OF HEAVY
RAIN...WOULD EXPECT RAPID RESPONDING RIVERS TO RISE THU
NGT...INCLUDING THE FOX AND PECATONICA RIVERS. THE ROCK RIVER WILL
ALSO LIKELY RESPOND BUT MORE SLOWLY IN ROCKCOUNTY. DUE TO THIS
THREAT...WL UPDATE HYDROLOGIC OUTLOOK STATEMENT.
.EXTENDED PERIOD...THURSDAY NIGHT THROUGH MONDAY...FORECAST
CONFIDENCE - MEDIUM TRENDING TO LOW.
WITH LARGE SCALE TROF SWEEPING EASTWARD ACROSS THE WESTERN GREAT
LAKES EARLY IN THE PERIOD AND WEAKER MID-LEVEL SHORT WAVE ENERGY
MOVING NORTHEAST ALONG BAROCLINIC ZONE DRAPED ACROSS SRN WI AND THE
ADJOINING REGION...WL CONTINUE CATEGORICAL POPS THURSDAY NIGHT.
CURRENTLY GFS OUTLIER WITH FASTER SOUTHEAST PROGRESS OF SFC FRONT
AND TIGHT BAROCLINIC ZONE THURSDAY NIGHT...WHICH WOULD HAVE GREATER
IMPACT ON LOW LEVEL THERMAL PROFILE. THIS WOULD INCREASE THE
PROBABILITY OF THE RAIN BECOMING MIXED WITH OR CHANGING OVER TO SNOW
ACROSS THE NORTHERN AND WESTERN CWA BEFORE THE PRECIP ENDS ON
FRIDAY. BOTH ECMWF AND GEM-NH SHOWING SLIGHTLY FASTER EWD
PROGRESSION AS WELL SO WL CONTINUE TO MENTION POTENTIAL FOR MIX OR
CHANGEOVER FROM WEST TO EAST 06Z-18Z FRI BEFORE PRECIP ENDS. NOT
EXPECTING ANY LAKE EFFECT OR ENHANCEMENT ON FRIDAY AS COLD AIR
SETTLES IN AS LOW LEVEL WINDS ANTICIPATED TO BE MORE NORTH TO
NORTHWEST WHILE DEEPER LOW LEVEL RH IS IN THE AREA. LOW LEVEL WINDS
DO VEER MORE NORTHEAST LATE FRI AND FRI NGT...HOWEVER LOW LEVEL
MOISTURE VERY LIMITED AT THIS TIME...AND WIND SPEEDS RAPIDLY
DIMINISH.
925H TEMPS FALL 10 TO 15C BY 00Z/SAT AND THESE COLDER TEMPERATURES
SHOULD REMAIN ENTRENCHED OVER SRN WI THROUGH THE WEEKEND INTO THE
FIRST DAYS OF DEC AS SHORT WAVE RIDGEING AND QUIETER CONDITIONS
AFFECT WISCONSIN. LATEST GFS MORE AGRESSIVE ON STRONGER PIECE OF
SHORT WAVE ENERGY MOVING NORTHEAST INTO THE CENTRAL MS VALLEY
INTO PARTS OF THE WESTERN GTLAKES ON MONDAY. ECMWF DOES SHOW
THIS STRENGTHENING LOW PRESSURE BUT WELL EAST AND SOUTH OF THE
REGION. WPC MEDIUM RANGE DESK TRENDING AWAY FROM DETERMINISTIC GFS
EARLY NEXT WEEK AND LEANING MORE ON DRIER ECMWF AND ECMWF ENSEMBLE.
HENCE WL KEEP POPS LOW FOR THE MONDAY TIMEFRAME.
&&
.AVIATION/00Z TAFS/...PRONOUNCED DRYING UPSTREAM PER VSBL SATELLITE
IMAGERY AND EXPECT QUIET CONDITIONS TO CONTINUE INTO TUESDAY WITH
HIGH PRESSURE RIDGE AXIS SLIDING INTO THE AREA TONIGHT AND THEN
SHIFTING OFF TO THE EAST ON TUESDAY. A LITTLE MORE UNCERTAINTY
ARISES LATER TONIGHT INTO TUESDAY MORNING. SREF CIG/VSBY PROG
SHOWING SOME HIGHER CONFIDENCE IN FOG/STRATUS DEVELOPMENT IN SRN WI
AS IS THE NAM MOS. TEMPS HAVE WARMED ABOVE FREEZING AND VSBL IMAGERY
SHOWS SOME MELTING HAS OCCURRED TODAY SO AS RIDGE AXIS DRAWS CLOSER
SOME FOG/STRATUS DEVELOPMENT POSSIBLE LATER TONIGHT INTO TUESDAY
MORNING...ESPECIALLY NEAR THE DEEPER SNOWCOVER IN FAR SRN WI.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
$$
TONIGHT AND TUESDAY/AVIATION...PC
TUESDAY NIGHT THROUGH MONDAY...MBK