Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/26/12

AREA FORECAST DISCUSSION

NWS ALBANY NY

640 PM EST SUN NOV 25 2012

.SYNOPSIS...
THE PERSISTENT CHILLY PATTERN WILL CONTINUE INTO AT LEAST THE
FIRST HALF OF THE WORK WEEK. A FEW UPPER LEVEL DISTURBANCES WILL
TRANSVERSE THE REGION PROVIDING PERIODS OF CLOUDS AND SOME LIGHT
SNOW OR SNOW SHOWERS. THOSE SNOW SHOWERS WILL BE MORE PROBLEMATIC
DOWNWIND OF THE GREAT LAKES AND IMPACT PORTIONS OF THE ADIRONDACKS
AND WESTERN MOHAWK VALLEY.

.NEAR TERM /THROUGH MONDAY/...
AS OF 600 PM EST...WE HAVE GONE AHEAD AN UPGRADED THE LAKE EFFECT
SNOW ADVISORY TO A LAKE EFFECT SNOW WARNING. THIS WAS DONE BASED ON
THE FACT THAT WE HAD GROUND TRUTH REPORTS THAT ALREADY 4 INCHES OF
SNOW ACCUMULATED JUST SINCE THE AFTERNOON ACROSS PORTIONS OF
NORTHERN HERKIMER COUNTY. THE LATEST RUC AND NAM CONTINUE TO PORTEND
THAT IF ANYTHING...THE LAKE BANDS CURRENTLY FOUND OVER THIS
REGION...WILL GO MORE ROBUST AND AS THE LOW LEVEL LAPSE RATE
ACTUALLY INCREASES...AND THE BAND MIGHT ACTUALLY BECOME MORE
CONCENTRIC WITH TIME THROUGH AROUND MIDNIGHT. THE LIQUID TO SNOW
RATIO LOOKS TO BE ABOUT 20:1 SO IT WON`T TAKE MUCH TO PILE IT UP TO
AROUND 8 INCHES ACROSS LOCALITIES IN NORTHERN HERKIMER COUNTY.

ALSO...SATELLITE PICTURES SUGGEST A TELECONNECTION HAS SETUP
BETWEEN GEORGIAN BAY AND LAKE ONTARIO WHICH WOULD SERVE TO
SIGNIFICANTLY ENHANCE THE LAKE BAND...ALLOWING IT TO MOVE FURTHER
INLAND.

FOR THE REMAINDER OF THE REGION...ONLY MINOR TWEAKS HERE AND THERE.
WE ARE SEEING SOME DBZ VALUES AROUND 20 LOCALLY BUT SO FAR ONLY
FLURRIES WITH THAT...MUCH OF WHAT WE SAW THROUGHOUT THE DAY.

RECENT RADAR TRENDS CONTINUE TO REVEAL AN INTENSIFYING BAND OF SNOW
COMING ASHORE ACROSS OSWEGO COUNTY AND 1KM ENHANCED VISIBLE IMAGERY
SUGGESTS THE CU/STRATOCU EXTENDS APPROX 120 MILES WESTWARD ACROSS
LAKE ONTARIO WITH HINTS OF CONTRIBUTIONS FROM SOUTHERN LAKE HURON.
FORECAST INVERSION HEIGHTS FROM THE BUFKIT PROFILES ACROSS THE
WESTERN MOHAWK VALLEY AND DOWNWIND OF LAKE ONTARIO SUGGEST LEVELS
WILL AVERAGE AROUND 9K FEET WHERE THE TOP OF THE INVERSION TOUCHES
THE -18 TO -20C. THIS WOULD POINT TOWARD THE POTENTIAL FOR SOME
LIGHTNING BUT WILL NOT INCLUDE IN THE GRIDS. HOWEVER...THIS WILL
ENHANCE SNOWFALL RATES AS THESE BANDS PROPAGATE INLAND. PER THE
CSTAR LAKE RESEARCH OF INLAND PENETRATION OF THESE LAKE BANDS
SUGGESTS OVER 100 MILE INLAND ASSUMING WE CONTINUE WITH SOUTHERN
LAKE HURON CONTRIBUTION. IF WE LOSE UPSTREAM CONNECTION...WE CAN CUT
THIS INLAND PENETRATION TO HALF WHICH WILL BE AN ISSUE FOR NORTHERN
HERKIMER COUNTY WITH ACCUMULATING SNOWFALL. FOR NOW...WE WILL FAVOR
THE WETTER SOLUTION AND THUS THE LAKE EFFECT SNOW WARNING FOR
NORTHERN HERKIMER COUNTY AND THE CONTINUATION OF THE LAKE EFFECT
ADVISORY FOR HAMILTON COUNTY. H2O VAPOR IMAGERY DOES SUGGEST A
COUPLE OF SHORT WAVES TRACKING ACROSS THE NORTHERN GREAT LAKES
REGION WHICH MAY DISRUPT THE FLOW AND BACK IT TO TAKE THE BAND A
LITTLE FURTHER NORTH BEFORE RETURNING TO A MORE WEST TO EAST FLOW
OVERNIGHT. REMAINDER OF THE REGION...EXPECTATIONS FOR ADDITIONAL
STRATUS CLOUDS AND PERHAPS SOME FLURRIES OR LIGHT SNOW SHOWERS WHICH
WILL BE MORE AN ISSUE ACROSS THE HIGHER TERRAIN AND ESPECIALLY INTO
THE CATSKILLS WITH LOWS RANGING FROM THE UPPER TEENS TO THE UPPER
20S /HIGHER VALUES ACROSS THE MID HUDSON VALLEY/.

WE HAVE ISSUED A PUBLIC STATEMENT (ALBPNSALY) REGARDING SNOWFALL
TOTALS. PLEASE REFER TO THE STATEMENT FOR ALL THE LATEST SNOWFALL
ACCUMULATIONS.

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
AS THE AFOREMENTIONED SHORT WAVE/S/ TRACK EAST OF THE REGION BY
SUNRISE MONDAY...LAKE BANDS WILL BEGIN TO SHIFT SOUTHWARD ACROSS
THE MOHAWK VALLEY AND WEAKEN AS DRIER AIR ALOFT AND LOWERING
INVERSION HEIGHTS COMMENCE. HOWEVER...THERE SHOULD REMAIN AN AMPLE
SCT-BKN STRATUS DECK THROUGHOUT THE REGION DESPITE SURFACE
PRESSURES RISING THROUGH THE DAY. HIGH TEMPERATURES MONDAY WILL
NOT BE TOO MUCH DIFFERENT THAN SUNDAYS HIGHS WITH MAINLY 20S FOR
THE HIGHER TERRAIN AND 30S ELSEWHERE.

SHORT WAVE...AS SEEN IN THE H2O VAPOR LOOP IMAGERY...WAS
APPROACHING THE BIG SKY COUNTRY OF MONTANA. THIS WAVE WILL DIVE
INTO THE NORTHERN TIER OF THE CONUS THROUGH MONDAY AND TRACK
SOUTHEAST ALONG THE FOOTHILLS OF THE ROCKIES. THE DOWNSTREAM UPPER
FLOW REMAINS RATHER CONFLUENT WHICH SUGGESTS THIS WAVE WILL NOT
TAP INTO THE SOUTHERN CONUS MOISTURE AND WILL HAVE TO UTILIZE THE
PACIFIC MOISTURE THAT WAS STREAMING ACROSS THE CENTRAL ROCKIES.
EXPECTATION...AS HAS BEEN WELL ADVERTISED IN THE ECMWF THE PAST
SEVERAL DAYS...IS FOR THIS WAVE TO TRACK MAINLY SOUTH OF THE
REGION MONDAY NIGHT INTO TUESDAY. THERE WILL BE ANOTHER
OPPORTUNITY FOR ADDITIONAL CLOUD SEEDING ACROSS THE GREAT LAKES
WITH AN RENEWED ENHANCEMENT OF LAKE ACTIVITY THROUGH THIS PERIOD.
ACCUMULATIONS UP TO A COUPLE OF INCHES ARE POSSIBLE ACROSS
NORTHERN HERKIMER AND HAMILTON COUNTIES WITH THIS LAKE
ENHANCEMENT. OTHERWISE...WITH RESPECT TO THE WAVE PASSING BY TO
OUR SOUTH...GLOBAL AND SHORT TERM MODELS CONTINUE TO SHOW A MORE
DRIER SOLUTION SOUTH OF ALBANY. FOR NOW...WE WILL CONTINUE WITH
THE CURRENT CHC-SCT POPS FOR LIGHT SOUTH SOUTH OF THE CAPITAL
DISTRICT AND FLURRY POTENTIAL ELSEWHERE. AS CLOUDS WILL BE
PREVALENT...HAVE KEPT TEMPS CLOSE TO OR SLIGHTLY COOLER THAN MOS
NUMBERS.

BY TUESDAY NIGHT...WE FIND OURSELVES IN-BETWEEN THE DEPARTING
SYSTEM TO OUR SOUTH AND THE NEXT UPSTREAM WAVE APPROACHING THE
CENTRAL GREAT LAKES REGION. WITH AN BRIEF ANTICYCLONIC SURFACE
FLOW AT THE SURFACE AND LACK OF UPPER LEVEL TRIGGERS...WE WILL
FORGO ANY MENTION OF PRECIP AT THIS TIME. SINCE SEVERAL BREAKS IN
THE OVERCAST ARE EXPECTED...WE WILL FOLLOW A COLDER SOLUTION WITH
RESPECT TO OVERNIGHT LOWS...ESPECIALLY WHERE FRESH SNOW COVER IS
EXPECTED.

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
THE EXTENDED OR LONG TERM PERIOD WILL BEGIN WITH A FRONTAL BOUNDARY
OR MAYBE TWO OF THEM CROSSING THE REGION ON WEDNESDAY. THE FRONTAL
BOUNDARY(S) COULD BRING SOME INNOCUOUS SNOW SHOWERS MAINLY TO AREAS
NORTH AND WEST OF THE CAPITAL DISTRICT...BUT ANY AMOUNTS SHOULD BE
FAIRLY LIGHT AND SCATTERED.

BEHIND THE FRONT...ANOTHER ROUND OF CHILLY NORTHWESTERLY FLOW WITH
H850 TEMPERATURES AROUND -10C...WILL LIKELY PRODUCE ANOTHER ROUND OF
LAKE EFFECT SNOW SHOWERS. AT THIS VANTAGE POINT...THIS DOES NOT LOOK
LIKE A SIGNIFICANT EVENT AS THE FLOW LOOKS TOO NORTHWESTERLY (AS
OPPOSED TO WESTERLY) AND ANTICYCLONIC. (A NORTHWESTERLY FLOW TENDS
TO BREAK THE BANDS APART MITIGATING HEAVIER AMOUNTS OF SNOWFALL AS
WELL AS KEEPING A LOT OF THE BANDS TO OUR WEST THE ANTICYCLONIC FLOW
SUPPRESSES ASCENT AND THUS LEFT MOISTURE AVAILABLE TO PRECIPITATE
OUT OF THE CLOUDS).

OF COURSE THIS SCENARIO WILL BE CLOSELY MONITORED AS GET CLOSER TO
THIS TIME FRAME TO SEE IF THERE ARE ANY CHANGES TO THIS CURRENT
THINKING.

MOST OF LAKE EFFECT ACTION WILL TAKE PLACE NORTH AND WEST OF ALBANY
(THE USUAL SUSPECTS...ADIRONDACKS/MOHAWK VALLEY...CATSKILLS).

BY THURSDAY...A BACK DOOR COLD FRONT IS FORECAST TO SLIP SOUTH
THROUGH OUR REGION...ENFORCING THE CHILLY AIR MASS...AND PERHAPS
BRINGING A FEW MORE SNOW SHOWERS TO OUR NORTHWESTERN AREAS.

A SMALL CANADIAN HIGH IS FORECAST TO QUICKLY BUILD IN THURSDAY
NIGHT TO BRING PERHAPS THE COLDEST NIGHT OF THE YEAR...ESPECIALLY
THOSE AREAS WHERE A SNOW PACK WILL BE IN PLACE (DOWNWIND OF LAKE
ONTARIO - MOHAWK VALLEY AND ADIRONDACKS). DRY COLD WEATHER LOOKS TO
HOLD INTO FRIDAY.

AFTER THAT...AS THE SURFACE HIGH WILL BEGIN TO SLIP
OFFSHORE...AND A SOUTHERLY FLOW WILL INITIALLY WARM THE MID LAYERS
OF THE ATMOSPHERE. OVERRUNNING OF THIS WARMER SLIGHTLY MORE MOIST
AIR COULD BRING A ROUND OF LIGHT WINTRY PRECIPITATION...BUT THIS
FAR OUT...WE WILL ONLY GO WITH SLIGHT CHANCES FRIDAY NIGHT THROUGH
SATURDAY NIGHT SINCE TIMING ISSUES ARE IMPOSSIBLE TO NAIL DOWN
THIS FAR OUT.

BY SUNDAY...THE SOUTHERLY FLOW SHOULD BRING MILDER TEMPERATURES BUT
STILL THE THREAT OF MAINLY LIQUID RAIN SHOWERS.

TEMPERATURES WILL CONTINUE TO RUN BELOW NORMAL THROUGH FRIDAY...WITH
HIGHS MAINLY IN THE 30S VALLEY LOCATIONS...20S HIGHER TERRAIN.
OVERNIGHT LOWS WILL BE IN THE 20S FROM ALBANY SOUTH AND EAST...TEENS
NORTH AND WEST...AND EVEN SINGLE NUMBERS COME FRIDAY MORNING IN
THOSE COLD SHELTERED SNOW COVERED MOUNTAIN VALLEYS.

SATURDAY/S HIGHS WILL BEGIN TO RETURN TO MORE SEASONABLE
LEVELS...STILL CHILLY IN THE 30S TO LOWER 40S...BUT THEN WARMING TO
HIGHER INTO THE 40S MOST PLACES BY SUNDAY.

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
MAINLY VFR CONDITIONS WILL LIKELY PREVAIL THROUGH MONDAY.

STILL DEALING WITH PLENTY OF LAKE EFFECT CLOUDS AT ALL BUT KPOU
WHERE OCCASIONALLY THEY FORM A CEILING THERE AS WELL. FOR THE MOST
PART...THESE ARE VFR CLOUDS WITH CLOUD BASES 4-6 KFT. LAKE EFFECT
SNOW SHOWERS HAVE HAPPENED AT KALB...BUT THUS FAR REALLY ONLY
FLURRIES WITH VERY LITTLE RESTRICTION TO VISIBILITY. WE DID INCLUDE
A TEMPO FOR 6 SM -SHSN THERE THROUGH 04Z AND WE DID INCLUDE A TEMPO
FOR A CIG OVC030.

AS THE FLOW BECOMES MORE SW ALOFT...THE LAKE EFFECT BAND WILL LIFT
NORTH POSSIBLY IMPACTING KGFL BUT UNLIKELY.

AT THE OTHER SITES VFR WILL PREVAIL WITH SIMILAR CLOUD BASES EXCEPT
KPOU WHICH LOOKS TO REMAIN MORE SCATTERED AT THE 4-6 KFT LEVEL.

THE CLOUDS AT ALL THE OTHER TAF SITES LOOK TO BECOME SCATTERED
OVERNIGHT.

THE GUSTY WINDS HAVE CEASED AND SHOULD BE WSW UNDER 10KTS THROUGHOUT
THE NIGHT.

A SURFACE TROUGH WILL MOVE THROUGH DURING MONDAY. BEHIND THAT
FEATURE THE WIND WILL VEER TO THE WEST AGAIN AND PICK UP IN SPEED A
BIT BY AFTERNOON...GENERALLY AROUND 12KTS...GUSTING TO AROUND 20KTS
AT MOST OF THE SITES. LOW LEVEL INSTABILITY AND LAKE ENHANCEMENT
WILL TEND TO PRODUCE VFR CIGS AGAIN...GENERALLY IN THE 4-6K FT
RANGE.

OUTLOOK...
MON NITE...VFR. NO SIG WX.
TUE-TUE NIGHT...VFR...CHC -SHSN SOUTH.
WED-FRI...VFR. NO SIG WX.

.HYDROLOGY...
NO HYDROLOGIC PROBLEMS ARE EXPECTED THROUGH THE NEXT 5 DAYS.

LAKE EFFECT SNOWS WILL IMPACT PORTIONS OF THE WESTERN ADIRONDACKS
AND WESTERN MOHAWK VALLEY THROUGH TONIGHT WHERE SEVERAL INCHES OF
NEW SNOW IS EXPECTED. OTHERWISE...A LIGHT ACCUMULATION OF SNOW MAY BE
POSSIBLE TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT TUESDAY
INTO TUESDAY NIGHT AS AN AREA OF LOW PRESSURE PASSES SOUTH OF LONG
ISLAND.

WITH THE COLDER AIRMASS IN PLACE SOME ICE WILL START TO DEVELOP ON
RIVERS AND PONDS ESPECIALLY ACROSS THE NORTH COUNTRY AND THE
HIGHER TERRAIN. SOME ICE EFFECTS COULD BE SEEN ON GAGES BY LATE
IN THE WEEK.

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...LAKE EFFECT SNOW WARNING UNTIL NOON EST MONDAY FOR NYZ032.
LAKE EFFECT SNOW ADVISORY UNTIL NOON EST MONDAY FOR NYZ033.
MA...NONE.
VT...NONE.

$$
SYNOPSIS...BGM
NEAR TERM...HWJIV/BGM
SHORT TERM...BGM
LONG TERM...HWJIV
AVIATION...HWJIV
HYDROLOGY...IAA/BGM

AREA FORECAST DISCUSSION

NWS ALBANY NY

610 PM EST SUN NOV 25 2012

ALSO...SATELLITE PICTURES SUGGEST A TELECONNECTION HAS SETUP
BETWEEN GEORGIAN BAY AND LAKE ONTARIO WHICH WOULD SERVE TO
SIGNIFICANTLY ENHANCE THE LAKE BAND...ALLOWING IT TO MOVE FURTHER
INLAND.

FOR THE REMAINDER OF THE REGION...ONLY MINOR TWEAKS HERE AND THERE.
WE ARE SEEING SOME DBZ VALUES AROUND 20 LOCALLY BUT SO FAR ONLY
FLURRIES WITH THAT...MUCH OF WHAT WE SAW THROUGHOUT THE DAY.

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
THE EXTENDED WILL BEGIN WITH A FRONTAL BOUNDARY OR MAYBE TWO OF THEM
CROSSING THE REGION ON WEDNESDAY. THE FRONTAL BOUNDARY(S) COULD
BRING SOME INNOCUOUS SNOW SHOWERS MAINLY TO AREAS NORTH AND WEST OF
THE CAPITAL DISTRICT...BUT ANY AMOUNTS SHOULD BE FAIRLY LIGHT AND
SCATTERED.

OF COURSE THIS SCENARIO WILL BE CLOSELY MONITORED AS GET CLOSER TO
THIS TIME FRAME TO SEE IF THERE ARE ANY CHANGES TO THIS CURRENT
THINKING.

MOST OF LAKE EFFECT ACTION WILL TAKE PLACE NORTH AND WEST OF ALBANY
(THE USUAL SUSPECTS...ADIRONDACKS/MOHAWK VALLEY...CATSKILLS).

BY THURSDAY...A BACK DOOR COLD FRONT IS FORECAST TO SLIP SOUTH
THROUGH OUR REGION...ENFORCING THE CHILLY AIR MASS...AND PERHAPS
BRINGING A FEW MORE SNOW SHOWERS TO OUR NORTHWESTERN AREAS.

BY SUNDAY...THE SOUTHERLY FLOW SHOULD BRING MILDER TEMPERATURES BUT
STILL THE THREAT OF MAINLY LIQUID RAIN SHOWERS.

SATURDAY/S HIGHS WILL BEGIN TO RETURN TO MORE SEASONABLE
LEVELS...STILL CHILLY IN THE 30S TO LOWER 40S...BUT THEN WARMING TO
HIGHER INTO THE 40S MOST PLACES BY SUNDAY.

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
STRATOCU CLOUDS OF AROUND 4-5 KFT ASSOCIATED WITH LAKE EFFECT
ACTIVITY WILL CONTINUE TO IMPACT THE REGION THROUGH THE TAF
PERIOD. A FEW LAKE EFFECT SNOW SHOWERS OR FLURRIES MAY MOVE
NEAR/ACROSS KALB THIS AFTN AND KGFL OVERNIGHT...BUT FLYING
CONDITIONS WILL REMAIN VFR AS VSBYS WILL REMAIN GREATER THAN 6SM
AT ALL TIMES. A FEW UPSLOPE CLOUDS ALONG WITH A NEARBY FLURRY MAY
ALLOW FOR SOME HIGH END MVFR CIGS AT KPSF THIS AFTN...BUT THIS
LOOKS TO BE BRIEF...AND IT WILL BE VFR THERE MOST OF THE TIME THIS
AFTN/EVENING.

CLOUDS WILL SCT OUT AT KPOU/KPSF/KALB OVERNIGHT AS THE BEST LAKE
MOISTURE SHIFT NORTH OF THESE SITES. KGFL MAY STILL SEE BKN-OVC CIGS
AROUND 4 KFT OVERNIGHT.

VFR CONDITIONS WILL CONTINUE ON MONDAY. SOME DIURNAL CLOUDS ARE
POSSIBLE...ESP FOR THE NORTHERN AND HIGHER TERRAIN SITES...DURING
THE DAY ON MONDAY BUT CIGS WILL REMAIN HIGH ENOUGH TO STAY VFR.

WESTERLY WINDS WILL CONTINUE TO BE GUSTY THIS AFTN...WITH A FEW
GUSTS OF 20-25 KTS POSSIBLE. THE GRADIENT WILL WEAKEN OVERNIGHT
ALLOWING FOR WINDS 10 KTS OR LESS AS THE WIND SWITCHES TO A SW
DIRECTION. DURING DAYTIME MIXING ON MONDAY...WINDS WILL RETURN TO A
WESTERLY DIRECTION AND BE A LITTLE GUSTY AT TIMES...WITH GUSTS UP TO
20 KTS POSSIBLE.

OUTLOOK...
SUN NITE-MON...VFR. NO SIG WX.
TUE-TUE NIGHT...VFR...CHC -SHSN SOUTH.
WED-FRI...VFR. NO SIG WX.

.HYDROLOGY...
NO HYDROLOGIC PROBLEMS ARE EXPECTED THROUGH THE NEXT 5 DAYS.

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL NOON EST MONDAY FOR NYZ032.
LAKE EFFECT SNOW ADVISORY UNTIL NOON EST MONDAY FOR NYZ033.
MA...NONE.
VT...NONE.

$$
SYNOPSIS...BGM
NEAR TERM...HWJIV/BGM
SHORT TERM...BGM
LONG TERM...HWJIV
AVIATION...FRUGIS
HYDROLOGY...IAA/BGM

AREA FORECAST DISCUSSION

NWS TAUNTON MA

436 PM EST SAT NOV 24 2012

.SYNOPSIS...
COOL AND BLUSTERY CONDITIONS ARE EXPECTED FOR THE REMAINDER OF
THE WEEKEND INTO EARLY NEXT WEEK. UNCERTAINTY REMAINS REGARDING
THE TRACK AND INTENSITY OF A STORM TUESDAY AND WEDNESDAY. MUCH
COLDER WEATHER IS EXPECTED BEHIND THE STORM LATE NEXT WEEK.

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
430 PM UPDATE... WINDS HAVE INCREASED LATE THIS AFTERNOON AS THE
MIXING DEPTH GETS TO NEAR 850 MB. A GUST TO 44 KTS JUST OCCURRED
AT WORCESTER AT 4 PM... WITH 32 KTS WAS REPORTED AT ORANGE MA AND
33 KTS AT PITTSFIELD AT 3 PM. THE NORTHWEST PRESSURE GRADIENT WILL
CONTINUE TO TIGHTEN UP THIS EVENING AND OVERNIGHT IN THE WAKE OF
AN UPPER LEVEL TROUGH SWINGING ACROSS NORTHERN NEW ENGLAND. WINDS
AT 3000-5000 FT OFF THE GROUND ARE FORECAST TO INCREASE TO 40-45
KNOTS OVERNIGHT. IT IS A TRICKY CALL FOR THE WINDS TONIGHT. BUFKIT
SHOWS THAT DESPITE THE COLD AIR ADVECTION...THE WINDS DIMINISH TO
15 KT OVER MOST OF THE INTERIOR AS THE TEMPERATURE DROPS AND THE
MIXING LEVEL IS NOT AS DEEP. A MAJOR EXCEPTION IS ALONG THE
COAST...EVERYWHERE FROM CAPE ANN TO CAPE COD AND ON THE RI
COAST...WHERE IT SHOULD REMAIN GUSTING TO 25 TO 30 KTS OVERNIGHT.

FOR THE MOST PART...LAKE EFFECT SNOW SHOWERS HAVE BEEN CONFINED TO
THE BERKSHIRES. HOWEVER...A LIGHT SPRINKLE WAS REPORTED AT 3 PM IN
NASHUA NH... SO SOME OF THE PRECIPITATION IS HITTING THE GROUND.
CANNOT RULE OUT A FLAKE OF SNOW MAINLY WEST OF THE CONNECTICUT
RIVER THIS EVENING BUT ACTIVITY SHOULD DIMINISH WITH NIGHTFALL.
THE RAP MODEL SHOWS NO PRECIPITATION AFTER 04Z.

LOWS MAINLY IN THE UPPER TEENS TO MID 20S EXCEPT NEAR 30 ALONG THE
IMMEDIATE SOUTH COAST.

&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
SUNDAY...
SHOULD BE RATHER SIMILAR TO TODAY. SUNSHINE SHOULD GIVE WAY TO A
FAST MOVING BATCH OF MID LEVEL CLOUDINESS IN THE AFTERNOON LEADING
TO PARTLY TO MOSTLY CLOUDY SKIES. USED A 50-50 BLEND OF GFS AND
NAM FOR SKY GRIDS SINCE THEY DIFFERED ON THE TIMING OF THESE CLOUDS.
IT WILL AGAIN BECOME WINDY WITH GUSTS TO 20 TO 30 KTS FROM MID
MORNING THROUGH MID AFTERNOON AS THE MIXING INCREASES. WINDS
SHOULD DIMINISH LATE IN THE AFTERNOON. HIGHS MAINLY IN THE 40S.

SUNDAY NIGHT...
BECOMING MOSTLY CLEAR WITH LIGHT WINDS AND LOWS 20-30.

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
* COLDER...DRY WEATHER EXPECTED EARLY NEXT WEEK
* A STORM IS LIKELY TO AFFECT THE AREA MID WEEK
* COLDER WEATHER EXPECTED LATE NEXT WEEK

24/12Z MODELS ARE STARTING TO SHOW SOME CONSISTENCY THROUGHOUT THE
LONG TERM PORTION OF THE FORECAST. THERE IS STILL PLENTY OF
UNCERTAINTY REGARDING THE MID WEEK STORM...THOUGH THE 06Z GFS/00Z
ECMWF/12Z GFS ALL HAVE SIMILAR SOLUTIONS WITH LOW PRESSURE MOVING
OFF THE MID ATLANTIC COAST AND TRAVELING JUST SOUTH OF THE 40/70
BENCHMARK AND BRINGING SNOW TO MUCH OF THE AREA WITH A FOCUS ON THE
SOUTHERN PORTIONS OF SOUTHERN NEW ENGLAND. HOWEVER...THE 12Z NAM
/AN OUTLIER AT THIS POINT/ SIMPLY HAS HIGH PRESSURE OVER THE REGION
AND NO INDICATION OF PRECIP AT ALL. WILL TREND TOWARD A
ECMWF/GFS/HPC SOLUTION... HOWEVER...KEEPING IN MIND ALL THE FLIP
FLOPPING AND UNCERTAINTY WILL ONLY TREND TOWARD IT.

ASIDE FROM THE STORM...THE WEATHER IS FAIRLY QUIET BOTH EARLY AND
LATE NEXT WEEK WITH NORTHWESTERLY FLOW BRINGING COLDER TEMPERATURES.

MONDAY...STRONG NORTHWESTERLY FLOW WILL CONTINUE TO KEEP TEMPS
SLIGHTLY BELOW NORMAL. HIGH PRESSURE BUILDS IN KEEPING MOSTLY CLEAR
SKIES THROUGH THE DAY AND INTO THE EVENING.

TUESDAY INTO WEDNESDAY...GIVEN THE NUMEROUS SOLUTIONS OVER THE LAST
SEVERAL DAYS AM STILL HESITANT TO MAKE A RUN FOR A SINGLE SOLUTION.
THAT SAID...THE ECMWF AND GFS HAVE STARTED TO FOCUS TOWARDS LOW
PRESSURE ON A SOUTHERLY TRACK ALONG OR JUST SOUTH OF THE 40/70
BENCHMARK FOR WINTER STORMS. AT THIS POINT...THIS SOLUTION BRINGS
HEAVY SNOW...LIKELY FOCUSED MORE ON THE SOUTHERN AREAS OF THE CWA
MAINLY ON TUESDAY NIGHT INTO WEDNESDAY. THERE ARE STILL OTHER
SOLUTIONS...THE NAM HAS HIGH PRESSURE OVER THE REGION TUESDAY.
HOWEVER...AT THIS POINT...THE ECMWF/GFS SOLUTION APPEARS THE MOST
LIKELY. WILL TREND TOWARD THIS SOLUTION...BUT CONFIDENCE IS STILL
LOW.

THURSDAY AND FRIDAY...DESPITE ALL THE DISCREPANCIES/UNCERTAINTY FOR
EARLIER IN THE PERIOD...THESE TWO PERIODS HAVE FAIRLY GOOD AGREEMENT
AMONGST THE MODELS. NORTHWESTERLY FLOW WITH THE COOLEST TEMPS OF
THE SEASON THUS FAR MOVING IN ON STRONG COLD AIR ADVECTION. LOOKS
LIKE A COLD AND BRISK END TO THE WEEK.

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT

OVERVIEW...MODERATE TO HIGH CONFIDENCE.
VFR CONDITIONS THROUGH SUNDAY NIGHT. SCATTERED LIGHT SNOW SHOWERS
SHOULD BE CONFINED TO BERKSHIRES THIS EVENING ALTHOUGH A FLAKE OR
TWO CANNOT BE RULED OUT AS FAR EAST AS THE CONNECTICUT RIVER
BEFORE 04Z. W-NW WINDS GUSTING TO 20-30 KTS MOST AREAS. WINDS MAY
DIMINISH TO 15 KTS IN THE INTERIOR OVERNIGHT. WINDS DIMINISHING
AGAIN IN THE LATE AFTERNOON SUNDAY EXCEPT ALONG THE COAST.

KBOS TAF...MODERATE TO HIGH CONFIDENCE.
VFR THROUGH SUNDAY NIGHT. W-NW WINDS WITH GUSTS TO 20-30 KT
TONIGHT AND SUNDAY.

KBDL TAF...HIGH CONFIDENCE. VFR THROUGH SUNDAY NIGHT. SLIGHT
CHANCE OF A FLURRY THIS EVENING. W-NW WINDS WITH GUSTS 20-30 KT
THIS EVENING AND AGAIN SUNDAY MID MORNING THROUGH MID AFTERNOON.

OUTLOOK...MONDAY THROUGH THURSDAY...

MONDAY...HIGH CONFIDENCE. VFR.

TUESDAY THROUGH WEDNESDAY MORNING...LOW CONFIDENCE. MVFR/IFR
CONDITIONS POSSIBLE IN POTENTIAL RA/SN/FZRA/SNPL.

WEDNESDAY AFTERNOON THROUGH THURSDAY...MODERATE TO HIGH CONFIDENCE.
VFR.

.MARINE...
MODERATE CONFIDENCE INTO SUNDAY NIGHT...

GALE WARNINGS CONTINUE FOR THE COASTAL WATERS INCLUDING NANTUCKET
SOUND...EXCEPT FOR THE INNER HARBORS AND BAYS WHERE SMALL CRAFT
ADVISORIES ARE POSTED. AS AN UPPER LEVEL SHORT WAVE TROUGH SWINGS
THROUGH NORTHERN NEW ENGLAND OVERNIGHT...W TO NW WINDS WILL
CONTINUE TO INCREASE OVER THE COASTAL WATERS...REACHING 35 KTS
OVER THE GALE WARNING AREA AND CONTINUING INTO MUCH OF SUNDAY.
THERE IS A CHANCE THAT A FEW GUSTS TO GALE FORCE COULD OCCUR
CLOSER TO THE COAST IN THE SMALL CRAFT ADVISORY AREA...BUT
FREQUENT GUSTS ARE NOT EXPECTED. ONE CONCERN IS A GUST TO 44 KTS
AT WORCESTER AIRPORT RIGHT AT 4 PM... BUT WE ARE THINKING THAT
THIS IS ELEVATIONAL AND STILL RELATED TO THE MAXIMUM MIXING OF THE
AFTERNOON. WE WILL NEED TO WATCH THIS CLOSELY IN CASE GALES ARE
NEEDED EVERYWHERE ALONG THE COAST OVERNIGHT.

SEAS ARE FORECAST TO CONTINUE TO BUILD TO 8 TO 11 FEET ACROSS THE
OUTER WATERS TONIGHT.

WINDS SHOULD BEGIN TO DIMINISH TO BELOW GALE FORCE IN THE
AFTERNOON BUT SMALL CRAFT ADVISORY LEVEL WIND GUSTS TO 25 KTS MAY
CONTINUE OVER THE OUTER WATERS THROUGH SUNDAY NIGHT. SLOWLY
SUBSIDING SEAS SUNDAY NIGHT.

OUTLOOK...MONDAY THROUGH THURSDAY...

MODERATE CONFIDENCE THROUGH THE PERIOD.

SEAS WILL FALL BELOW 5 FEET LATE MONDAY AND REMAIN BELOW THROUGH
LATE TUESDAY. THEN SEAS WILL BUILD AGAIN AS LOW PRESSURE APPROACHES
THE WATERS LATE TUESDAY INTO WEDNESDAY AND REMAIN ABOVE 5 FEET
THROUGH THE PERIOD. WINDS WILL REMAIN BELOW 25 KTS THROUGH TUESDAY.
WINDS INCREASE TO 25 TO 30 KTS WEDNESDAY AND THURSDAY AS LOW
PRESSURE MOVES ACROSS THE WATERS. LOW PROBABILITY OF GALES LATE
WEDNESDAY INTO THURSDAY.

.FIRE WEATHER...
NO HEADLINES ARE ANTICIPATED BUT FELT IT WAS WORTH MENTIONING THAT
THE MINIMUM RELATIVE HUMIDITIES WILL BE DOWN AROUND 30 PERCENT
SUNDAY AFTERNOON. WINDS WILL BE GUSTING TO 20 TO 30 MPH BUT WILL
BE DIMINISHING IN THE MID TO LATE AFTERNOON AT THE TIME OF THE
MINIMUM HUMIDITIES.

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...GALE WARNING UNTIL 10 AM EST SUNDAY FOR ANZ232>235-237-256.
SMALL CRAFT ADVISORY UNTIL 7 PM EST SUNDAY FOR ANZ230-231-236-
251.
GALE WARNING UNTIL 1 PM EST SUNDAY FOR ANZ250-254-255.

$$
SYNOPSIS...RLG/GAF
NEAR TERM...GAF
SHORT TERM...GAF
LONG TERM...RLG
AVIATION...RLG/GAF
MARINE...RLG/GAF
FIRE WEATHER...GAF

AREA FORECAST DISCUSSION

NWS TAUNTON MA

1036 AM EST SAT NOV 24 2012

.SYNOPSIS...
COOLER AND BLUSTERY CONDITIONS ARE EXPECTED FOR THE REMAINDER OF
THE WEEKEND INTO EARLY NEXT WEEK. UNCERTAINTY REMAINS REGARDING
THE TRACK AND INTENSITY OF A POTENTIAL STORM NEXT TUESDAY AND
WEDNESDAY.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1030 AM UPDATE... COLD FRONT WAS EXITING THE COASTAL WATERS. WEST
TO NORTHWEST WINDS WERE GUSTING AS HIGH AS 30 KT AT BOS AND 28 KT
AT CEF. AM EXPECTING WIND GUSTS TO REMAIN IN THE 20-25 KT RANGE
THIS AFTERNOON WITH A FEW HIGHER GUSTS. SURFACE WINDS MAY INCREASE
TOWARD EVENING IN WESTERN AREAS AS 850 MB WINDS STRENGTHEN.

DRIER AIR HAS FILTERED IN WITH DEWPOINTS ALREADY IN THE UPPER
TEENS AND LOWER 20S ACROSS THE REGION. AFTER INITIAL
SUNSHINE...SOME CUMULUS CLOUDS HAD ALREADY FORMED IN SOUTHWEST NH
AND WESTERN MA. THESE SHOULD SPREAD EAST ACROSS MUCH OF THE
INTERIOR BUT MAY NOT REACH THE SOUTHERN COASTAL AREAS. NO CHANGES
TO TEMPERATURES FROM PREVIOUS FORECAST...WITH HIGHS IN THE MID 40S
AND HOLDING RELATIVELY STEADY OR SLOWLY FALLING INTO THE UPPER
30S.

A PERSISTENT LAKE EFFECT SNOW SHOWER BAND WAS MOVING ACROSS NEW
YORK AND IT WAS FLURRYING AT ALBANY AS OF 10 AM. THE RAP MODEL
SHOWS FLURRIES MAKING IT INTO BERKSHIRE COUNTY AND SOUTHERN VT
BUT NOT ANY FURTHER WITH THE DOWNSLOPE DRYING FLOW. WILL KEEP AN
EYE ON THIS.

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
TONIGHT...

THE CONTINUED STRONG COLD AIR ADVECTION THRU THE MAJORITY OF THE
ATMOS COLUMN WILL KEEP LOW-LVLS WELL-MIXED TO H8. WIND GUSTS LIKELY
TO CONTINUE AT 25 TO 30 MPH /GALES OVER THE WATERS/. H85 W/NW FLOW
WILL BE SLIGHTLY STRONGER WITHIN THE TIGHTER PRES GRADIENT. LOOKING
AT H85 TEMPS AROUND -10 TO -12C. WHILE LOOKING TO REMAIN MOSTLY
CLEAR... WINDS WILL DIMINISH THE POTENTIAL FOR EFFECTIVE NOCTURNAL
COOLING. STILL...ANTICIPATING LOWS DOWN INTO THE LOW 20S WITH UPR
TEENS TO THE N/W INTERIOR NEW ENGLAND.

SUNDAY...

ANOTHER DAY OF CONTINUED BLUSTERY W/NW CONDITIONS WITH GUSTS 25 TO
30 MPH /POTENTIAL FOR CONTINUED GALES ACROSS THE WATERS/. VERY
LITTLE CHANGE IN THE AIRMASS WITH H85 TEMPS AROUND -8 TO -10C...SO
EXPECTING MAX TEMPS AROUND THE LOW 40S WITH PERHAPS INCREASING
CLOUDS LATE WITH WEAK WAVE ENERGY TRANSLATING THRU THE LONGWAVE
PATTERN /CLIPPER SYSTEM/.

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
* COLDER...DRY WEATHER EXPECTED EARLY NEXT WEEK
* A STORM IS LIKELY TO AFFECT THE AREA MID WEEK

OVERVIEW AND MODEL PREFERENCES...
24/00Z MODEL GUIDANCE SUITE CONTINUES TO SHOW DECENT RUN-TO-RUN
CONSISTENCY AND GOOD AGREEMENT BETWEEN EACH OTHER THROUGH THE MID
TERM PERIOD. THEY HAVE ALSO BEGUN TO CONVERGE ON THE MID WEEK
SYSTEM THAT HAS BEEN DISCUSSED OF LATE. THIS IS NOT TO SAY ITS A
SLAM DUNK AT THIS POINT...BUT MODELS ARE NOW CLOSER TO ONE ANOTHER
IN THE LOW TRACK THAN PREVIOUS RUNS. ESSENTIALLY...WITH THE ZONAL
PROGRESSIVE FLOW ALOFT SUGGESTED IN ALL MODELS...THE GFS/ECMWF AND
RESPECTIVE ENSEMBLE MEANS NOW SUPPORT CYCLOGENESIS OFFSHORE OF THE
MID ATLANTIC STATES AND PUSHING THAT LOW FURTHER E THAN
/ESPECIALLY THE GFS AND GEFS/ GUIDANCE WAS PREVIOUSLY.
THEREFORE...THERE IS A BIT MORE SUPPORT FOR A COASTAL STORM RATHER
THAN ONE THAT PUSHES INLAND. THIS ALSO FAVORS A COOLER SOLN AS
WELL. THERE ARE STILL SIGNIFICANT TRACK DIFFERENCES THOUGH AS THE
GFS AND GEFS MEAN BRINGS THE LOW IN CLOSE PROXIMITY TO THE 40/70
BENCHMARK WHILE ECMWF/ECENS ARE MUCH FURTHER OFFSHORE WITH LITTLE
IMPACT ON SRN NEW ENGLAND. WILL BEGIN TO TREND GRIDS TOWARD THIS
COASTAL/COOL SOLN BUT WITH AN EYE TOWARD UNCERTAINTY IN FINAL
IMPACTS...WHICH WILL NEED TO BE MONITORED THROUGH THE WEEKEND AND
EARLY NEXT WEEK. COOL HIGH PRES BOOKEND THIS STORM EARLY THIS
COMING WEEK AND AGAIN LATE IN THE WEEK...AND GUIDANCE IS ACTUALLY
IN GOOD AGREEMENT HERE SO CONFIDENCE IS HIGHER IN COOL/DRY
CONDITIONS SURROUNDING THE STORM TEMPORALLY.

DETAILS...

SUN NIGHT INTO EARLY TUE...
STRONG UPPER LVL ZONAL JET WITH COOL NW FLOW AT THE SFC SUPPORT
TEMPS GENERALLY BELOW NORMAL AND OCCASIONALLY BLUSTERY CONDITIONS
THROUGH THIS PERIOD. MON...A FAST MOVING SHORTWAVE MAY ENHANCE THE
LOW LVL COLD ADVECTION AND USHER IN SOME LOW CLOUDS ASSOCIATED
WITH STRATO-CU DEVELOPMENT DOWNSTREAM OF THE GREAT LAKES. AT THIS
POINT...THE STRONG COLD ADVECTION SHOULD PREEMPT ANY PRECIP
DEVELOPMENT WITH THIS WAVE...SO DRY CONDITIONS ARE LIKELY TO
CONTINUE.

TUE AFTERNOON INTO WED NIGHT...
AS MENTIONED EARLIER CONFIDENCE IS /ALBEIT A LITTLE BIT/ HIGHER
THAN PREVIOUS FORECASTS REGARDING THE TRACK OF A LOW PRES DURING
THE MID WEEK TIMEFRAME. MOST GUIDANCE NOW SUPPORTS THE LOW TRACKS
OFFSHORE...A SUGGESTION THE THE ECENS/OPERATIONAL ECMWF HAS
SUPPORTED FOR SOME TIME NOW. THEREFORE...A COLDER SOLN IS
POSSIBLE...BUT GIVEN THE TRACK COULD BE CLOSE TO THE BENCHMARK
/THE GFS/CMC TRACK/ OR WELL OFFSHORE /THE ECMWF TRACK/ THE ACTUAL
EFFECTS ON SRN NEW ENGLAND REMAIN A BIT OF A QUESTION MARK. AT
THIS POINT THE MID LVL FLOW REGIMES ON BOTH OPERATIONAL MODELS DO
SO SOME POSSIBLE DEFORMATION...SO FORCING FOR PRECIP IS POSSIBLE
PARTICULARLY IN THE ERN HALF OF THE FA. AS MENTIONED EARLIER WILL
TREND GRIDS TOWARD THIS MORE OFFSHORE SOLN WITH THIS UPDATE...BUT
CARRY POPS ACROSS THE ENTIRE REGION AS THERE ARE STILL SOME
FACTORS THAT WILL HAVE TO BE IRONED OUT IN THE NEXT FEW DAYS. WILL
ALSO CONTINUE TO SHOW SOME SNOWFALL POSSIBLE PARTICULARLY W OF THE
I-495 AND I-95 CORRIDOR ALTHOUGH AMOUNTS WILL BE STRONGLY
CORRELATED TO THE FINAL TRACK...WHICH REMAINS IN QUESTION.

THU INTO EARLY WEEKEND...
WITH SOME ISSUES REGARDING THE TRACK OF THE SFC LOW AND ITS
ASSOCIATED WAVE THERE ARE STILL A FEW QUESTIONS REGARDING ANY FAST
MOVING SHORTWAVES DIVING OVER SRN NEW ENGLAND IN THE NW FLOW.
SUSPECT THAT MUCH OF THIS PERIOD WILL BE DRY AS MOST GUIDANCE
SUPPORTS HIGH PRES BUILDING IN ESPECIALLY FRI. WILL LEAN ON A DRY
COOL FORECAST GIVEN THE NW FLOW ATTM.

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT

OVERVIEW...MODERATE TO HIGH CONFIDENCE.
VFR CONDITIONS IN THE WAKE OF A COLD FRONT THIS AFTERNOON.
BKN-OVC CUMULUS CLOUDS AT 4000-5000 FT IN WESTERN AND CENTRAL
PORTIONS THROUGH THIS AFTERNOON. W-NW WINDS GUSTING TO 20-30 KT.
AN ISOLATED FLURRY POSSIBLE IN THE NRN BERKSHIRES AND EXTREME SWRN
NH. VFR TONIGHT.

KBOS TAF...MODERATE TO HIGH CONFIDENCE.
VFR. GUSTS TO 20-30 KT THIS AFTERNOON INTO TONIGHT.

KBDL TAF...HIGH CONFIDENCE. VFR. W-NW WINDS WITH GUSTS AROUND
25 KT INTO THIS EVENING.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

SUNDAY NIGHT THROUGH MONDAY...HIGH CONFIDENCE.
VFR. MAYBE SOME MVFR CIGS IN THE ERN SLOPES OF THE BERKSHIRES.

TUESDAY AND WEDNESDAY...LOW CONFIDENCE.
MVFR/IFR CONDITIONS POSSIBLE IN POTENTIAL
RA/SN/FZRA/SNPL...DEPENDENT ON THE TRACK OF LOW PRES.

.MARINE...
MODERATE TO HIGH CONFIDENCE INTO SUNDAY...

GALE WARNINGS HOISTED IN EXPECTATION OF STRONG W/NWLY FLOW IN WAKE
OF THE COLD FRNT DEVELOPING BY MIDDAY WITH GUSTS AT OR EXCEEDING 34
KTS. WILL KEEP SMALL CRAFT ADVISORIES POSTED FOR THE INNER HARBORS
AND BAYS. DUE TO THE STRONG W/NW FLOW...SEAS WILL BUILD TO 8 TO
10 FEET ACROSS THE OUTER WATERS INTO THIS EVENING.

WINDS ALOFT INCREASE THIS EVENING AND TONIGHT. WILL BE EVALUATING
TO SEE WHETHER GALE WARNINGS NEED TO BE EXTENDED TO THE INNER
HARBORS AND BAYS.

OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...

MODERATE CONFIDENCE THROUGH THE PERIOD.

SEAS...
SEAS DROP BRIEFLY BELOW 5 FT ESPECIALLY NEAR SHORE WATERS MON.
HOWEVER...SWELL WILL HAVE LITTLE TIME TO SUBSIDE BELOW 5 FT
THROUGH THE PERIOD ON THE OUTER WATERS. SO EXPECT AFTER BRIEF
PERIOD OF DIMINISHING SEAS INTO MON THAT SWELL WILL ONCE AGAIN
BUILD IN ADVANCE OF LOW PRES TUE INTO WED. WITH SEAS OF 5-8 FT
POSSIBLE ONCE AGAIN BY MID WEEK.

WINDS...
SUN NIGHT INTO MON WINDS OF 20-25 KT ARE LIKELY. WINDS DIMINISH
OVER THE WATERS TUE AND TUE NIGHT. HOWEVER A COASTAL STORM MAY
BRING ANOTHER CHANCE FOR GALE FORCE WINDS /AT LEAST SMALL CRAFT
LEVEL/ BY WED.

OVERALL...VERY NARROW WINDOW FOR CONDITIONS BELOW SMALL CRAFT
THRESHOLDS MON NIGHT INTO EARLY TUE. OTHERWISE...WHETHER IT BE
SEAS OR WINDS...SMALL CRAFT ADVISORIES ARE LIKELY THROUGH MUCH OF
THE PERIOD. THERE IS ALSO THE POSSIBILITY OF SOME GALES BY WED
DEPENDING ON THE TRACK OF LOW PRES.

.FIRE WEATHER...
MUCH COOLER AND DRIER AIR THIS AFTERNOON WITH W/NW WINDS GUSTING
UP TO 30 MPH. WHILE WE HAVE NOT SEEN A DECENT RAINFALL SINCE
NOVEMBER 13TH...AND STRONG WINDS ARE FORECAST...RELATIVE
HUMIDITIES ARE ANTICIPATED TO REMAIN AT OR ABOVE THE 30 PERCENT
THRESHOLD. THEREFORE WEATHER CONDITIONS WILL REMAIN JUST AT OR
ABOVE CRITERIA FOR ISSUING FIRE WEATHER HEADLINES.

$$
SYNOPSIS...DOODY/SIPPRELL
NEAR TERM...FIELD
SHORT TERM...SIPPRELL
LONG TERM...DOODY
AVIATION...FIELD/SIPPRELL/DOODY
MARINE...FIELD/SIPPRELL/DOODY
FIRE WEATHER...FIELD/SIPPRELL

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

407 PM CST SAT NOV 24 2012

.DISCUSSION...
234 PM CST

THE FORECAST CHALLENGES FOR TODAY ARE MAINLY TEMPERATURES AS
READINGS LOOK TO WARM LATER THIS EVENING THROUGH THE DAY SUNDAY
THEN A COOL DOWN INTO MONDAY...FOLLOWED BY A WARM-UP WITH WHAT
LOOKS TO POTENTIALLY BE 50S TO END NOVEMBER AND START
METEOROLOGICAL WINTER.

THE STUBBORN CYCLONIC FLOW AND ITS PESKY STRATUS IS ON THE WAY OUT
WITH A SURFACE RIDGE AXIS MOVING QUICKLY OVER THE AREA THIS EVE.
MID-LEVEL WARM AIR ADVECTION CLOUDS ARE ALREADY SPREADING OVER THIS
RIDGE ACROSS WESTERN IL AND SHOULD QUICKLY EXPAND EAST THROUGH THE
EVE. BEFORE THE ARRIVAL OF THESE CLOUDS IN THE HOURS AFTER
SUNSET...EASTERN AREAS SHOULD SEE TEMPERATURE DROPS THROUGH THE
20S GIVEN LIGHT WINDS. A GRADUAL CLIMB IN TEMPERATURES IS THEN
EXPECTED AREA WIDE AS PRESSURE FALLS AND RETURN FLOW SPREAD IN.
TEMPERATURES ARE LIKELY TO CLIMB BACK TO THE UPPER 20S TO MID 30S
BY DAYBREAK ON SUNDAY.

THE WARM AIR ADVECTION CLOUDS TONIGHT ARE ASSOCIATED WITH A STRONG
UPPER LEVEL LOW MOVING EAST ACROSS NORTHERN SASKATCHEWAN AND
MANITOBA...AND MORE SO WITH A RELATED PV ANOMALY AND SHORT WAVE
EXTENDING SOUTHWARD. THIS WILL TRANSLATE INTO WI BY OVERNIGHT AND
ALREADY TO THE EASTERN GREAT LAKES BY SUNDAY MORNING. SUPPORT FOR
UPWARD MOTION DOES SPREAD THIS FAR SOUTH AS REFLECTED IN RAP AND
NAM Q-VECTOR CONVERGENCE FIELDS. HOWEVER...SATURATION AND MID-
LEVEL MOISTURE CONVERGENCE IS BETTER SITUATED TO THE NORTH. THIS
DISJOINT WILL LIKELY KEEP PRECIPITATION TO THE NORTH...THOUGH
FLURRIES COULD GET CLOSE TO THE WI/IL STATE LINE LATER THIS EVE.

THE WARM SECTOR OF THIS CLIPPER-LIKE SYSTEM WILL CONTINUE OVER THE
AREA INTO SUNDAY. THIS HAS OFFERED 40S TO THE WEST OF THE REGION
IN NEBRASKA TODAY...AND ENVISION LOWER TO MID 40S DURING THE DAY
SUNDAY HERE. AS THE COLD FRONT MOVES THROUGH...WINDS WILL TURN
MORE NORTHWEST BY NIGHT AND TEMPERATURES WILL FALL BACK INTO THE
20S FOR LOWS.

TRENDS CONTINUE TO SUPPORT THIS LOW-LEVEL COOL AIR AND RIDGING
PUSH FROM THE NORTH TO EVOLVE THE PRIMARY BAROCLINIC ZONE TO THE
SOUTH OF THE AREA ON MON NIGHT AND TUE...AND THUS KEEP THE
PRIMARY FORCING FOR PRECIPITATION THERE AS WELL. AS THIS UNFOLDS
THOUGH...THERE STILL IS A WINDOW FOR SMALL CHANCES OF LIGHT SNOW
ACROSS THE SOUTHERN FORECAST AREA...MAINLY LATER MONDAY AFTERNOON
AND NIGHT. THE SPREAD IN THE SREF AND GEFS MEMBERS IS NOW LOW OVER
THE AREA...SO CONFIDENCE ON THIS IS FAIRLY HIGH.

BEYOND THIS...TEMPERATURES WILL SLOWLY MODERATE THROUGH MID WEEK
AS UPPER LEVEL RIDGING ACROSS THE WESTERN STATES EASES EAST.
WITH A LARGE CLOSED LOW OFF THE WEST COAST FORECAST CONSISTENTLY
BY GUIDANCE...THERE WILL BE LITTLE PROGRESSION OF MAJOR WEATHER
SYSTEMS. A QUICK MOVING UPPER LEVEL JET MAX AND ASSOCIATED SHORT
WAVE IS SEEN ON THU NIGHT/FRIDAY WITHIN THE SUITE OF LONG RANGE
GUIDANCE. AGAIN THERE CONTINUES TO BE DECENT BUT SHORT-LIVED
DYNAMICS FORECAST WITH THIS. HAVE INCREASED POPS SOME FROM A
PROVIDED GUIDANCE BLEND. TEMPERATURE SPREAD BY DAYS 6 AND 7 IN THE
FORECAST REALLY INCREASES IN GUIDANCE...SO CONFIDENCE
DROPS...HOWEVER GUIDANCE IS FAVORING TEMPERATURES TO BE ABOVE
NORMAL. ONE OF THE REASONS FOR SUCH SPREAD LOOKS TO BE CLOUD
COVER...AS THE DETERMINISTIC GFS DRAGS UP QUITE A BIT OF LOW-LEVEL
JUICE WITH THE THU NIGHT/FRI WAVE THAT MAY BE TOUGH TO SCOUR THIS
TIME OF YEAR.

MTF

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 22Z...

* NONE.

BMD

//DISCUSSION...UPDATED 18Z...

HIGH PRESSURE IS BUILDING INTO NORTHERN ILLINOIS AND NORTHWEST
INDIANA AT MIDDAY. THIS IS FINALLY ERODING THE CLOUD DECK THAT
HAS PERSISTED THROUGH THE MORNING. HOWEVER THE CLEARING WILL BE
SHORT LIVED AS MIDDLE AND HIGH LEVEL CLOUDS AHEAD OF AN
APPROACHING UPPER LEVEL TROUGH ARE ALREADY INTO EASTERN IA AND
MOVING TO THE EAST. THESE VFR-LEVEL CEILINGS WILL MOVE INTO ALL THE
TERMINALS LATE THIS AFTERNOON INTO THE EVENING HOURS. THE TROUGH
HAS LIMITED MOISTURE TO WORK WITH...SO NOT EXPECTING ANY
PRECIPITATION WITH IT. THE BIGGEST IMPACT WILL BE TO SHIFT THE
WINDS TO THE NORTHWEST AND SCATTER OUT THE CEILINGS AS IT MOVES
ACROSS THE AREA ON SUNDAY.

PAW

//ORD AND MDW CONFIDENCE...UPDATED 22Z...

* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.

BMD

//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...

SUNDAY NIGHT...VFR.
MONDAY...VFR. CHC OF LGT SN AND MVFR IN THE EVENING.
TUESDAY...CHC OF MVFR EARLY...TRENDING VFR LATE.
WEDNESDAY THROUGH THURSDAY...VFR.
FRIDAY...VFR. SLIGHT CHC LGT RA/SN AND PATCHY MVFR.

BEACHLER

.MARINE...

217 PM...A RIDGE OF HIGH PRESSURE WILL PASS ACROSS LAKE MICHIGAN
EARLY THIS EVENING AS LOW PRESSURE OVER SOUTHERN MANITOBA MOVES
EAST ACROSS THE NORTHERN LAKES SUNDAY AND WEAKENS SUNDAY NIGHT.
THE GRADIENT WILL TIGHTEN TONIGHT BETWEEN THE APPROACHING LOW AND
THE WEAKENING RIDGE. WEST WINDS WILL SHIFT SOUTHWESTERLY THIS
EVENING AND STEADILY INCREASE TO 15-25KTS BY LATE EVENING AND
OVERNIGHT. SOME GUSTS TO 30 KTS ARE POSSIBLE ESPECIALLY OVER THE
SOUTHERN PART OF THE LAKE WHERE THE GRADIENT WILL BE TIGHTEST. A
TRAILING COLD FRONT FROM THIS LOW WILL MOVE ACROSS THE LAKE SUNDAY
AFTERNOON SHIFTING WINDS WESTERLY. AS ANOTHER AREA OF HIGH
PRESSURE MOVES SOUTHEAST FROM THE NORTHERN PLAINS SUNDAY NIGHT TO
THE SOUTHERN LAKES AND OHIO VALLEY MONDAY...THE GRADIENT WILL ONCE
AGAIN TIGHTEN WITH NORTHWEST WINDS 20-25KTS EXPECTED. GRADIENT
COULD BE STRONG ENOUGH FOR GUSTS TO 30KTS OVER NORTHERN LAKE
MICHIGAN. AS THIS HIGH SETTLES SOUTH OF THE LAKE ON TUESDAY...
WINDS WILL TURN SOUTHWESTERLY AND SHOULD RAPIDLY STRENGTHEN
TUESDAY AFTERNOON AS ANOTHER LOW MOVES ACROSS ONTARIO AND THE
NORTHERN LAKES WITH 30KTS AGAIN POSSIBLE OVER THE NORTHERN HALF OF
THE LAKE. ANOTHER AREA OF HIGH PRESSURE WILL MOVE ACROSS THE
MIDWEST AND LAKES REGION MID WEEK. CMS

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

234 PM CST SAT NOV 24 2012

.DISCUSSION...
234 PM CST

MTF

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 20Z...

* LIGHT SOUTHWEST TO WEST WIND.

PAW

//DISCUSSION...UPDATED 18Z...

HIGH PRESSURE IS BUILDING INTO NORTHERN ILLINOIS AND NORTHWEST
INDIANA AT MIDDAY. THIS IS FINALLY ERODING THE CLOUD DECK THAT
HAS PERSISTED THROUGH THE MORNING. HOWEVER THE CLEARING WILL BE
SHORT LIVED AS MIDDLE AND HIGH LEVEL CLOUDS AHEAD OF AN
APPROACHING UPPER LEVEL TROUGH ARE ALREADY INTO EASTERN IA AND
MOVING TO THE EAST. THESE VFR-LEVEL WILL CEILINGS TO MOVE INTO
ALL THE TERMINALS LATE THIS AFTERNOON INTO THE EVENING HOURS. THE
TROUGH HAS LIMITED MOISTURE TO WORK WITH...SO NOT EXPECTING ANY
PRECIPITATION WITH IT. THE BIGGEST IMPACT WILL BE TO SHIFT THE
WINDS TO THE NORTHWEST AND SCATTER OUT THE CEILINGS AS IT MOVES
ACROSS THE AREA ON SUNDAY.

PAW

//ORD AND MDW CONFIDENCE...UPDATED 20Z...

* HIGH CONFIDENCE IN WIND TREND.

PAW

//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...

BEACHLER

.MARINE...

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 4 PM SATURDAY.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

217 PM CST SAT NOV 24 2012

.DISCUSSION...
930 AM CST

HAVE MADE SOME ADJUSTMENTS TO THE FORECAST TO HOLD ONTO CLOUDS
LONGER...PARTICULARLY ACROSS NORTHEAST IL AND NORTHWEST IN...AND
ACCORDINGLY HAVE LOWERED FORECAST HIGH TEMPS BY A COUPLE DEGREES
IN PLACES.

THE GOES WATER VAPOR LOOP THIS MORNING IS REFLECTING DRYING MOVING
EASTWARD OVER THE AREA...AND REGIONAL SOUNDINGS REFLECTED THAT IN
THE MID-LEVELS. HOWEVER...HEIGHT RISES AT 700 MB WERE NEUTRAL THIS
MORNING INDICATING LIMITED OVERALL SUPPRESSION...AS WAS 700 TO
850 MB TEMPERATURE ADVECTION /DVN AND GRB EVEN COOLED AT 700 MB/.
WITH PROFILERS ALSO INDICATING MORE OF A NORTHERLY FLOW IN THE
LOW-LEVELS...GENERAL CYCLONIC FLOW APPEARS TO BE HANGING ON
LONGER THAN INITIAL THOUGHT...ESPECIALLY ACROSS EASTERN AREAS.
THIS REGIME WILL NOT AID THE CLOUDS IN CLEARING THROUGH EARLY
AFTERNOON...EVEN WITH THE MOIST LAYER AT THE CLOUD HEIGHT
REMAINING SHALLOW /1000 FT OR LESS/ ON AMDAR SOUNDINGS AND THE GRB
RAOB THIS MORNING. ADAPTING AN AREA AMDAR SOUNDING IT WOULD SEEM
THAT SURFACE TEMPS IN THE MID 30S WOULD BE NEEDED TO MIX OUT SOME
OF THE CLOUD COVER...AND WITH NO WARMING HAPPENING UNDER THE HEART
OF THE CLOUDS AND MUCH LOWER STARTING TEMPERATURES THIS MORNING AT
THE PERIPHERY OF THE CLOUD SHIELD...DO NOT SEE THIS HAPPENING
ANYTIME SOON. SO OUTSIDE OF A COUPLE HOLES FROM THE WEAK TO
SUPPRESSION ALOFT...THE CLOUD SHIELD SHOULD ONLY OOZE ITS WAY
EAST THROUGH EARLY AFTERNOON THEN INCREASE IN SPEED WITH THE WARM
AIR ADVECTION PATTERN. EVEN AT 3 PM THOUGH...PARCEL TRAJECTORIES
OVER EASTERN AREAS ARE FROM CLOUD COVERED SOUTH CENTRAL WI AT
PRESENT. THE RAP 900 MB RH FORECAST SEEMS TO CAPTURE THE EVOLUTION
WELL...AND IS IN GOOD AGREEMENT WITH THE NARRE-TL CLOUD FORECAST.
SO HAVE COLLABORATED THESE IDEAS INTO THE CLOUD COVER FORECAST
AND KEPT TEMPERATURES CLIMBING AT ABOUT 1 DEGREE PER TWO HOURS
ACROSS THE EAST THROUGH EARLY AFTERNOON. OVERALL THIS TOOK HIGHS
DOWN 1 TO 3 DEGREES IN PLACES.

MTF

//PREV DISCUSSION...
352 AM CST

FOLLOWING AN ACTIVE HOLIDAY WEEK WITH DENSE FOG THANKSGIVING EVE
MORNING FOLLOWED BY NEAR RECORD WARMTH ON THANKSGIVING DAY... AND
THEN A JOLT BACK TO REALITY COURTESY OF A STRONG COLD FRONT ON
BLACK FRIDAY... THE COMING WEEKEND WILL BE RELATIVELY QUIET WITH
CHILLY DAYTIME HIGHS SATURDAY ONLY IN THE 30S... WITH MAX TEMPS
SUNDAY RETURNING TO AROUND SEASONAL NORMS.

AS DEEP SURFACE LOW PRESSURE OVER QUEBEC CONTINUES TO PUSH NE AWAY
FROM THE GREAT LAKES... RIDGING WILL BUILD QUICKLY INTO NRN IL/NW IN
THIS MORNING. THE STRENGTHENING ANTI-CYCLONIC FLOW COMBINED WITH
INCREASED SUBSIDENCE THROUGH THE MID LEVELS SHOULD DRY OUT STUBBORN
LINGERING SC FAIRLY QUICKLY FROM WEST TO EAST THROUGH THE MID
MORNING HOURS. DESPITE SUNSHINE THROUGH THE REMAINDER OF THE DAY...
TEMPS WILL ONLY RISE INTO THE MID 30S WITH COLD AIR AT 850 MB
HANGING AROUND UNTIL THE BETTER WARM AID ADVECTION (WAA) PATTERN
SETS UP ACROSS THE AREA THIS EVENING.

WITH LOW LEVEL WAA COMBINED WITH RISING HEIGHTS ALOFT EXPECT MIN
TEMPS TONIGHT TO BE REALIZED THIS EVENING WITH TEMPS THEN STEADYING
OUT BY LATE EVENING AND PROBABLY EVEN RISING A FEW DEGREES DURING
THE OVERNIGHT. EXPECT CLOUDS TO INCREASE AHEAD OF A FAIRLY POTENT
SECONDARY SHORTWAVE TROUGH DROPPING INTO THE UPPER GREAT LAKES
TONIGHT INTO EARLY SUNDAY. ANY FORCING OF CONSEQUENCE REMAINS NORTH
OF THE LOCAL AREA HOWEVER AND HENCE EXPECT PRECIP TO DO LIKEWISE.

SUNDAY SHAPING UP TO BE A FAIRLY TYPICAL LATE NOVEMBER DAY WITH
CLOUDS GIVING WAY TO SOME SUN AND TEMPS TOPPING OUT IN THE MID 40S.
A WEAK COLD FRONT ASSOCIATED WITH AFOREMENTIONED UPPER SHORTWAVE
TROUGH WILL SWEEP ACROSS THE REGION DURING THE AFTERNOON BUT SHOULD
RESULT IN LITTLE MORE THAN A WIND SHIFT AS COLDEST CORE OF AIR
BEHIND IT WILL REMAIN TO OUR NORTH.

MODELS CONTINUE TO TREND FARTHER SOUTH WITH LOW PRESSURE DEVELOPING
OVER THE SOUTHERN PLANS ON MONDAY AND THEN TRACKING ACROSS THE LOWER
MISSISSIPPI VALLEY MONDAY NIGHT AND ACROSS THE SOUTH ON TUES. WITH
THIS TREND BECOMING MORE PRONOUNCED... WILL CONTINUE PREVIOUS
FORECAST TREND OF LOWERING POPS ACROSS THE CWFA ANOTHER NOTCH FOR
THE MON NIGHT-TUES TIME PERIOD. SHOULD THIS MORE SOUTHERN TRACK
VERIFY... AT LEAST THE NORTHERN 2/3 OF THE CWFA IF NOT THE ENTIRE
AREA WILL PROBABLY SEE NO PRECIP AT ALL... HOWEVER GIVEN SOME
UNCERTAINTY REMAINING IN THE ENSEMBLE SPREAD... WOULD LIKE TO SEE
ANOTHER MODEL RUN BEFORE PULLING COMPLETELY.

A DRY NORTHWESTERLY FLOW ALOFT SETS UP FOR WED AND THURS WITH
BROAD HIGH PRESSURE DOMINATING AT THE SURFACE AND SEASONAL TEMPS.
THEN LEE SIDE CYCLOGENEIS DEVELOPS IN RESPONSE TO AN UPPER LEVEL
TROUGH MOVING INTO THE CENTRAL PLAINS LATER ON THURSDAY AND MOVES
INTO THE LOCAL AREA LATE THURSDAY NIGHT INTO FRIDAY. HAVE
INTRODUCED LOW POPS WITH THIS FEATURE AS DYNAMICS INITIALLY
APPEAR REASONABLY IMPRESSIVE HOWEVER AT DAYS 6-7 WOULD LIKE TO
SEE GREATER MODEL CONSISTENCY BEFORE INTRODUCING MENTION OF
ANYTHING MORE THAN A SLIGHT CHANCE OF PRECIP. THE AIR MASS IN
PLACE AT THE TIME WILL BE SUFFICIENTLY COLD ENOUGH TO SUPPORT A
MIX OF RAIN AND SNOW INITIALLY EARLY FRIDAY BEFORE INCREASING WAA
WARMS THE COLUMN TO AT OR ABOVE THE FREEZING MARK.

ED F

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 20Z...

* LIGHT SOUTHWEST TO WEST WIND.

PAW

//DISCUSSION...UPDATED 18Z...

HIGH PRESSURE IS BUILDING INTO NORTHERN ILLINOIS AND NORTHWEST
INDIANA AT MIDDAY. THIS IS FINALLY ERODING THE CLOUD DECK THAT
HAS PERSISTED THROUGH THE MORNING. HOWEVER THE CLEARING WILL BE
SHORT LIVED AS MIDDLE AND HIGH LEVEL CLOUDS AHEAD OF AN
APPROACHING UPPER LEVEL TROUGH ARE ALREADY INTO EASTERN IA AND
MOVING TO THE EAST. THESE VFR-LEVEL WILL CEILINGS TO MOVE INTO
ALL THE TERMINALS LATE THIS AFTERNOON INTO THE EVENING HOURS. THE
TROUGH HAS LIMITED MOISTURE TO WORK WITH...SO NOT EXPECTING ANY
PRECIPITATION WITH IT. THE BIGGEST IMPACT WILL BE TO SHIFT THE
WINDS TO THE NORTHWEST AND SCATTER OUT THE CEILINGS AS IT MOVES
ACROSS THE AREA ON SUNDAY.

PAW

//ORD AND MDW CONFIDENCE...UPDATED 20Z...

* HIGH CONFIDENCE IN WIND TREND.

PAW

//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...

BEACHLER

.MARINE...

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 4 PM SATURDAY.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

148 PM CST SAT NOV 24 2012

.DISCUSSION...
930 AM CST

MTF

//PREV DISCUSSION...
352 AM CST

ED F

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 20Z...

* LIGHT SOUTHWEST TO WEST WIND.

PAW

//DISCUSSION...UPDATED 18Z...

HIGH PRESSURE IS BUILDING INTO NORTHERN ILLINOIS AND NORTHWEST
INDIANA AT MIDDAY. THIS IS FINALLY ERODING THE CLOUD DECK THAT
HAS PERSISTED THROUGH THE MORNING. HOWEVER THE CLEARING WILL BE
SHORT LIVED AS MIDDLE AND HIGH LEVEL CLOUDS AHEAD OF AN
APPROACHING UPPER LEVEL TROUGH ARE ALREADY INTO EASTERN IA AND
MOVING TO THE EAST. THESE VFR-LEVEL WILL CEILINGS TO MOVE INTO
ALL THE TERMINALS LATE THIS AFTERNOON INTO THE EVENING HOURS. THE
TROUGH HAS LIMITED MOISTURE TO WORK WITH...SO NOT EXPECTING ANY
PRECIPITATION WITH IT. THE BIGGEST IMPACT WILL BE TO SHIFT THE
WINDS TO THE NORTHWEST AND SCATTER OUT THE CEILINGS AS IT MOVES
ACROSS THE AREA ON SUNDAY.

PAW

//ORD AND MDW CONFIDENCE...UPDATED 20Z...

* HIGH CONFIDENCE IN WIND TREND.

PAW

//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...

BEACHLER

.MARINE...
258 AM CST

OCCASIONAL GALES CONTINUE ACROSS THE NORTHERN HALF OF LAKE MICHIGAN
EARLY THIS MORNING...HOWEVER THE FREQUENCY CONTINUES TO DIMINISH.
THUS IT APPEARS THE GALE WARNING WILL BE ALLOWED TO EXPIRE AT
ISSUANCE OF THE NEW GLF. WILL MENTION AN OCCASIONAL GALE FORCE GUST
TO 35 KT THROUGH DAYBREAK. THEN EXPECT WINDS TO STEADILY DIMINISH.
HIGH PRESSURE WILL BEGIN TO BUILD IN FROM THE WEST...WHICH WILL
ALLOW WINDS TO FURTHER DIMINISH AND BECOME WESTERLY THIS
AFTERNOON. WILL CONTINUE TO FEATURE THE SMALL CRAFT ADVISORY
THROUGH EARLY THIS AFTERNOON...POSSIBLY ENDING EARLIER FOR THE
ILLINOIS NEARSHORE WATERS. WINDS WILL CONTINUE TO DIMINISH
THROUGHOUT THE AFTERNOON AND EARLY EVENING...HOWEVER THE HIGH
PRESSURE WILL QUICKLY DRIFT SOUTHEAST OF THE REGION. THIS WILL
ALLOW ANOTHER TIGHT GRADIENT TO RETURN LATE TONIGHT WITH WINDS
INCREASING FROM THE W/SW TO 15-25 KT. THIS WILL ALLOW WAVES ACROSS
THE NORTHERN TIER OF LAKE MICHIGAN TO BUILD TONIGHT. THEN ANOTHER
BOUNDARY WILL SLIDE ACROSS THE LAKE SUNDAY THAT WILL ONCE AGAIN
ALLOW WINDS TO TURN NORTHWEST. WITH COLD AIR FLOWING OVER LAKE
MICHIGAN...WAVES SHOULD EASILY BUILD LATER IN THE WEEKEND. THEN
YET ANOTHER AREA OF HIGH PRESSURE APPEARS TO BUILD INTO THE REGION
EARLY IN THE UPCOMING WEEK...WHICH SHOULD ALLOW WINDS TO DIMINISH
MONDAY TO AROUND 10-20 KT BEFORE INCREASING AHEAD OF YET ANOTHER
WEAK LOW PRESSURE AND FRONTAL BOUNDARY.

CONFIDENCE...MEDIUM/LOW.

BEACHLER

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 4 PM SATURDAY.

AREA FORECAST DISCUSSION

NWS LINCOLN IL

1157 AM CST SAT NOV 24 2012

.DISCUSSION...
ISSUED 1030 AM CST SAT NOV 24 2012

UPDATED THE FORECAST TODAY FOR DECREASING LOW CLOUDS OVER EAST
CENTRAL IL AND ALONG THE WABASH RIVER VALLEY IN SOUTHEAST IL TODAY.
ALSO HAVE INCREASING MID/HIGHL CLOUDS OVER WESTERN AND CENTRAL IL
DURING THIS AFTERNOON. SO VARIABLE CLOUD COVER ACROSS CENTRAL AND
SE IL TODAY. ANOTHER CHILLY LATE FALL DAY WITH HIGHS IN THE MID TO
UPPER 30S. BUT LIGHTER NW WINDS OF 5 TO 10 MPH TODAY AS HIGH
PRESSURE RIDGE DRIFTS EAST FROM THE MS VALLEY ACROSS IL DURING
THIS AFTERNOON.

LOW STRATOCUMULUS CLOUD DECK WITH CEILING FROM 1500-2500 FT DRIFTED
SOUTHWARD ACROSS EASTERN IL THIS MORNING AND CURRENTLY EXTEND
ALONG AND EAST OF A LACON TO LINCOLN TO EFFINGHAM TO OLNEY LINE.
THESE CLOUDS BLANKET MUCH OF IN/MI AND EASTERN WI TOO. MEANWHILE MID/HIGH
CLOUDS ABOVE 8K FT WERE OVER MUCH OF IA/MO AND THE CENTRAL/NORTHERN
PLAINS AND DRIFTING SE TOWARD WEST CENTRAL IL WITH CIRRUS CLOUDS
20-25K FT OVER MO AND SW IL. 10 AM TEMPS WERE IN THE MID TO UPPER
20S WITH OLNEY AND SPRINGFIELD UP TO 30F. DEWPOINTS WERE IN THE
UPPER TEENS TO AROUND 20F. WNW WINDS LESS THAN 10 MPH PREVAILED
THIS MORNING.

1031 MB HIGH PRESSURE OVER EAST TEXAS AND RIDGING ACROSS THE MS
VALLEY WILL SETTLE ACROSS THE GULF COAST STATES BY 06Z/MIDNIGHT
TONIGHT AND RIDGING NORTHWARD INTO THE TN/OH VALLEYS. RIDGE AXIS
TO DRIFT EAST OF IL BY SUNSET WITH WNW WINDS UNDER 10 MPH TURNING
SSW LATE TODAY AND EVENING. 850 MB TEMPS OF MINUS 4-6C AT 12Z MODIFY
FROM SW TO NE DURING THE AFTERNOON REACHING MINUS 3C TO 1C BY
SUNSET BUT LIMITED SURFACE WARM AIR ADVECTION PLUS SOME CLOUD
COVER AND COLD START TO DAY WILL KEEP HIGHS IN THE MID TO UPPER
30S WITH MILDEST READINGS FROM SPRINGFIELD SW.

.AVIATION...
ISSUED 1155 AM CST SAT NOV 24 2012

MVFR BROKEN TO OVERCAST CEILINGS 1.5-2K FT FROM STRATOCUMULUS DECK
OVER EASTERN IL AT CMI WILL SCATTERED OUT BY MID AFTERNOON AS DEC
RECENTLY HAS SCATTERED OUT AND BMI WILL TOO IN THE NEXT HOUR.
MEANWHILE BROKEN TO TO OVERCAST MID/HIGH CLOUDS ABOVE 8K FT OVER
IA AND WEST CENTRAL IL WILL SPREAD INTO CENTRAL IL FROM WEST TO
EAST DURING THE AFTERNOON AND REMAIN IN PLACE TONIGHT AND SUNDAY
MORNING. AIRMASS QUITE DRY WITH DEWPOINTS IN THE UPPER TEENS TO
AROUND 20F SO NO FOG EXPECTED NEXT 24 HOURS. THOUGH DEC HAD MVFR
VSBYS 4-5 MILES WITH HAZE THIS MORNING BUT VSBY HAS RECENTLY ROSE
TO 7 MILES. 1030 MB HIGH PRESSURE OVER EAST TX AND RIDGING ACROSS
THE MS VALLEY WILL DRIFT EAST ACROSS THE SOUTHEAST STATES BY
18Z/NOON SUNDAY. WSW WINDS 5-9 KTS THIS AFTERNOON TO TURN SOUTH
THIS EVENING AND THEN W/SW 9-13 KTS SUNDAY MORNING AS A WEAKENING
FRONT MOVES INTO CENTRAL IL BY MIDDAY SUNDAY.

.PREV DISCUSSION...
ISSUED 225 AM CST SAT NOV 24 2012

LATEST SURFACE MAP SHOWING HIGH PRESSURE RIDGE EXTENDING FROM
OKLAHOMA NORTHWARD INTO MINNESOTA. WIDESPREAD STRATOCUMULUS IN THE
CYCLONIC FLOW OVER THE GREAT LAKES HAS PUSHED SOUTHWARD TO ABOUT A
PONTIAC TO PARIS LINE AS OF 2 AM. LARGE SHIELD OF MID AND HIGH
CLOUDS ALSO DROPPING SOUTHEAST FROM THE NORTHERN AND CENTRAL PLAINS.

THE PRIMARY FORECAST CONCERN INVOLVES THE PRECIPITATION POTENTIAL
MONDAY AND MONDAY NIGHT...INCLUDING ANY WINTER PRECIP TYPES...AS A
STORM SYSTEM PASSES TO OUR SOUTH.

SHORT TERM...TODAY THROUGH MONDAY NIGHT...

LATEST RAP MODEL AND VAD WIND PROFILES AT 925 MB SUGGEST THE
LOWER CLOUDS SHOULD NOT MAKE MUCH FURTHER WESTWARD PROGRESS...AND
BEGIN TO PULL EASTWARD LATER THIS MORNING. HIGH CLOUDS STREAMING
IN FROM THE NORTHWEST WILL YIELD PARTLY TO MOSTLY SUNNY CONDITIONS
TODAY. TEMPERATURES EXPECTED TO REMAIN RATHER CHILLY TODAY WITH
MID TO UPPER 30S COMMON...AS THE RIDGE AXIS MOVES OVERHEAD.
RETURN FLOW EXPECTED TO BEGIN SETTING UP AROUND SUNSET.
TEMPERATURES ACROSS THE WESTERN CWA EXPECTED TO LEVEL OFF BY
MIDNIGHT...AND PERHAPS RISE A COUPLE DEGREES LATE. HIGHS ON SUNDAY
SHOULD BE ABOUT 10-15 DEGREES WARMER.

LARGE UPPER TROUGH OVER THE EASTERN CONUS TO BREAK DOWN THIS
WEEKEND AS SOME AMPLIFICATION TAKES PLACE ALONG THE WEST COAST.
FAST MOVING JET STREAK OF AROUND 75 KNOTS AT 500 MB WILL PUSH A
BOUNDARY ACROSS THE CWA ON SUNDAY...BUT CLOUDS WILL BE THE MAIN
EFFECT FROM IT. OF MORE CONCERN IS A STORM SYSTEM DEVELOPING ALONG
THE TEXAS/OKLAHOMA BORDER LATE SUNDAY NIGHT AND MONDAY. WHILE THE
EVENING MODELS ALL KEEP THE PARENT SURFACE LOW WELL TO OUR
SOUTH...MOISTURE WILL BE DRAWN NORTH AS A SHORTWAVE IN THE
NORTHERN JET STREAM MOVES INTO THE PLAINS. GFS/CANADIAN MODELS
DRAW THE PRECIPITATION AS FAR NORTH AS ABOUT THE I-72 CORRIDOR BY
MONDAY EVENING...WHILE THE NAM/ECMWF MODELS KEEP ALL THE PRECIP TO
OUR SOUTH. THESE LATTER MODELS MAY BE A LITTLE ON THE FASTER
SIDE...ESPECIALLY THE ECMWF...SO WILL LEAN MORE TOWARD THE SLOWER
SOLUTIONS. AS SUCH...WILL HAVE THE HIGHEST POPS ACROSS THE
SOUTHEAST CWA...ESPECIALLY MONDAY AFTERNOON AND NIGHT. FORECAST
SOUNDINGS INDICATE A RAIN TO SNOW TRANSITION MONDAY EVENING ACROSS
THE SOUTHEAST CWA AND LIGHT SNOW ELSEWHERE...BUT A PERSISTENT DRY
NORTHEAST FLOW WILL KEEP PRECIP TOTALS DOWN. HAVE KEPT AREAS
NORTHWEST OF THE ILLINOIS RIVER WITH MAINLY SLIGHT CHANCE
POPS...WHERE HIGH PRESSURE WILL BUILD IN TO THE AREA.

LONG TERM...TUESDAY THROUGH FRIDAY...

MAINLY QUIET CONDITIONS EXPECTED DURING THIS TIME FRAME. UPPER
RIDGING OVER THE WESTERN U.S. SHOULD TRANSITION TO MORE OF A ZONAL
FLOW AS THE WEEK PROGRESSES...WITH MODERATING TEMPERATURES. LONGER
RANGE MODELS PUSH A FAST MOVING SHORTWAVE THROUGH THE STATE LATE
THURSDAY NIGHT OR EARLY FRIDAY. THE GFS IS THE WETTER OF THE
MODELS WITH THIS FEATURE BUT MAINLY KEEPS THE PRECIPITATION JUST
TO OUR NORTH...SO WILL KEEP THE EXTENDED FORECAST DRY.

GEELHART

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

1137 AM CST SAT NOV 24 2012

.DISCUSSION...
930 AM CST

MTF

//PREV DISCUSSION...
352 AM CST

ED F

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 18Z...

* LIGHT WEST WINDS BECOMING LIGHT SOUTHWEST BY LATE AFTERNOON.

* CEILINGS AT 2500-3000 FT BECOMING SCATTERED CLOUDS BY 19Z.

PAW

//DISCUSSION...UPDATED 18Z...

HIGH PRESSURE IS BUILDING INTO NORTHERN ILLINOIS AND NORTHWEST
INDIANA AT MIDDAY. THIS IS FINALLY ERODING THE CLOUD DECK THAT
HAS PERSISTED THROUGH THE MORNING. HOWEVER THE CLEARING WILL BE
SHORT LIVED AS MIDDLE AND HIGH LEVEL CLOUDS AHEAD OF AN
APPROACHING UPPER LEVEL TROUGH ARE ALREADY INTO EASTERN IA AND
MOVING TO THE EAST. THESE VFR-LEVEL WILL CEILINGS TO MOVE INTO
ALL THE TERMINALS LATE THIS AFTERNOON INTO THE EVENING HOURS. THE
TROUGH HAS LIMITED MOISTURE TO WORK WITH...SO NOT EXPECTING ANY
PRECIPITATION WITH IT. THE BIGGEST IMPACT WILL BE TO SHIFT THE
WINDS TO THE NORTHWEST AND SCATTER OUT THE CEILINGS AS IT MOVES
ACROSS THE AREA ON SUNDAY.

PAW

//ORD AND MDW CONFIDENCE...UPDATED 18Z...

* HIGH CONFIDENCE IN WIND TREND.

* HIGH CONFIDENCE IN CEILING TREND AND TIMING.

PAW

//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...

BEACHLER

.MARINE...
258 AM CST

CONFIDENCE...MEDIUM/LOW.

BEACHLER

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 4 PM SATURDAY.

AREA FORECAST DISCUSSION

NWS LINCOLN IL

1030 AM CST SAT NOV 24 2012

.DISCUSSION...
ISSUED 1030 AM CST SAT NOV 24 2012

.AVIATION...
ISSUED 503 AM CST SAT NOV 24 2012

A LARGE AREA OF MVFR CLOUDS IS AFFECTING BMI AND CMI THIS MORNING.
BASED ON SATELLITE TRENDS...APPEARS THIS CLOUD DECK WILL NOT GET
ANY FURTHER WEST THIS MORNING...THOUGH IT IS COMING CLOSE TO DEC
AND PIA. MODELS DO NOT HAVE A GOOD HANDLE ON THIS LOW LEVEL
MOISTURE AT THIS TIME...SO WILL TRY TO FORECAST CLEARING AT BMI
AND PIA BASED ON SHIFTING OF HIGH PRSS RIDGE...WHICH SHOULD BE
SOMETIME LATER THIS MORNING. SPI/PIA/DEC WILL REMAIN CLEAR THIS
MORNING. ALL SITES WILL ALSO SEE AN INCREASE...AND LOWERING...OF
MID CLOUDS THIS AFTERNOON...IN RESPONSE TO THE WAA THAT BEGINS TO
RETURN THIS AFTERNOON ONCE THE HIGH PRSS RIDGE MOVES EAST OF THE
AREA. ONCE THIS MOVES THROUGH...THE HIGH CIRRUS CLOUDS SHOULD BE
THE RULE FOR THE NIGHT. WINDS WILL BE LIGHT WEST-NORTHWESTERLY
THIS MORNING AND THEN BECOME SOUTH-SOUTHWESTERLY THIS AFTERNOON
AND THEN CONTINUE INTO THE NIGHT. WINDS SPEEDS WILL NOT INCREASE
TO AFTER 06Z LATE TONIGHT.

AUTEN
&&

.PREV DISCUSSION...
ISSUED 225 AM CST SAT NOV 24 2012

THE PRIMARY FORECAST CONCERN INVOLVES THE PRECIPITATION POTENTIAL
MONDAY AND MONDAY NIGHT...INCLUDING ANY WINTER PRECIP TYPES...AS A
STORM SYSTEM PASSES TO OUR SOUTH.

SHORT TERM...TODAY THROUGH MONDAY NIGHT...

LONG TERM...TUESDAY THROUGH FRIDAY...

GEELHART

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

947 AM CST SAT NOV 24 2012

.DISCUSSION...
930 AM CST

MTF

//PREV DISCUSSION...
352 AM CST

ED F

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 16Z...

* CEILINGS IN THE 2500-3000 FT RANGE THROUGH ABOUT 18Z...THEN
BECOMING SCATTERED.

* WEST TO NORTHWEST WIND 10 KT OR LESS GRADUALLY BECOMING MORE
SOUTHWEST TO WEST BY LATE AFTERNOON.

PAW

//DISCUSSION...UPDATED 16Z...
CLOUD DECK HAS BEEN SLOW TO ERODE FROM THE WEST THIS MORNING SO
HAVE SLOWED DOWN THE IMPROVEMENT BY A COUPLE HOURS. MAY HAVE TO
SLOW IT EVEN FURTHER.

PREVIOUS DISCUSSION FROM 12Z...
LOW PRESSURE CONTINUES TO DEPART THE REGION WITH AN AREA OF HIGH
PRESSURE SLOWLY BUILDING INTO THE WESTERN GREAT LAKES FROM THE
CENTRAL PLAINS. BETWEEN THE TWO SYSTEMS A STRATUS LAYER HAS
REMAINED ACROSS NORTHERN IL/NORTHWEST IN AIRFIELDS EARLY THIS
MORNING...AND WILL PERSIST THRU 16Z. THEN DRY WILL CONTINUE TO
ERODE THE OVC CIGS...THINNING THE STRATUS DECK TO A SCT DECK ARND
MID-MORNING. IN ADDITION WINDS WILL TURN W/SW BY MIDDAY/EARLY
AFTN. THIS WILL ALLOW ADDTL DRY AIR TO FILTER INTO THE
REGION...LIFTING THE BORDERLINE MVFR OR LOW END VFR CIGS TO ALL
VFR CONDS. WINDS WILL THEN SLOWLY TURN S BY THIS EVE...HOWEVER
REMAIN AT OR LESS THAN 10 KT. AFT 06Z SUN...THE GRADIENT BEGINS TO
RETURN AND GUIDANCE SUGGESTS THAT WINDS WILL BEGIN TO INCREASE
TOWARDS DAYBREAK SUN FROM THE S TO AROUND 10 TO 15 KT. OTHERWISE
VFR CONDS WILL PREVAIL WITH JUST SOME MID-DECK CLOUDS ARND 8KFT
AGL SLIDING OVERHEAD.

BEACHLER

//ORD AND MDW CONFIDENCE...UPDATED 16Z...

* HIGH CONFIDENCE IN WIND TREND.

* HIGH CONFIDENCE IN CEILING TREND...MEDIUM CONFIDENCE IN TIMING.

PAW

//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...

BEACHLER

.MARINE...
258 AM CST

CONFIDENCE...MEDIUM/LOW.

BEACHLER

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 4 PM SATURDAY.

AREA FORECAST DISCUSSION...UPDATED

NWS CHICAGO/ROMEOVILLE IL

931 AM CST SAT NOV 24 2012

.DISCUSSION...
930 AM CST

MTF

.PREV DISCUSSION...
352 AM CST

ED F

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 14Z...

* CEILINGS IN THE 2500-3000 FT RANGE THROUGH 16Z...THEN BECOMING
SCATTERED.

* NORTHWEST WINDS AROUND 10 KT BECOMING WEST BY MIDDAY AND
SOUTHWEST BY LATE AFTERNOON.

PAW

//DISCUSSION...UPDATED 12Z...

LOW PRESSURE CONTINUES TO DEPART THE REGION WITH AN AREA OF HIGH
PRESSURE SLOWLY BUILDING INTO THE WESTERN GREAT LAKES FROM THE
CENTRAL PLAINS. BETWEEN THE TWO SYSTEMS A STRATUS LAYER HAS
REMAINED ACROSS NORTHERN IL/NORTHWEST IN AIRFIELDS EARLY THIS
MORNING...AND WILL PERSIST THRU 16Z. THEN DRY WILL CONTINUE TO
ERODE THE OVC CIGS...THINNING THE STRATUS DECK TO A SCT DECK ARND
MID-MORNING. IN ADDITION WINDS WILL TURN W/SW BY MIDDAY/EARLY
AFTN. THIS WILL ALLOW ADDTL DRY AIR TO FILTER INTO THE
REGION...LIFTING THE BORDERLINE MVFR OR LOW END VFR CIGS TO ALL
VFR CONDS. WINDS WILL THEN SLOWLY TURN S BY THIS EVE...HOWEVER
REMAIN AT OR LESS THAN 10 KT. AFT 06Z SUN...THE GRADIENT BEGINS TO
RETURN AND GUIDANCE SUGGESTS THAT WINDS WILL BEGIN TO INCREASE
TOWARDS DAYBREAK SUN FROM THE S TO AROUND 10 TO 15 KT. OTHERWISE
VFR CONDS WILL PREVAIL WITH JUST SOME MID-DECK CLOUDS ARND 8KFT
AGL SLIDING OVERHEAD.

BEACHLER

//ORD AND MDW CONFIDENCE...UPDATED 14Z...

* HIGH CONFIDENCE IN WIND TREND.

* HIGH CONFIDENCE IN CEILING TREND...MEDIUM CONFIDENCE IN TIMING.

PAW

//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...

BEACHLER

.MARINE...
258 AM CST

CONFIDENCE...MEDIUM/LOW.

BEACHLER

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 4 PM SATURDAY.

AREA FORECAST DISCUSSION

NWS LINCOLN IL

503 AM CST SAT NOV 24 2012

.DISCUSSION...
ISSUED 225 AM CST SAT NOV 24 2012

THE PRIMARY FORECAST CONCERN INVOLVES THE PRECIPITATION POTENTIAL
MONDAY AND MONDAY NIGHT...INCLUDING ANY WINTER PRECIP TYPES...AS A
STORM SYSTEM PASSES TO OUR SOUTH.

SHORT TERM...TODAY THROUGH MONDAY NIGHT...

LONG TERM...TUESDAY THROUGH FRIDAY...

GEELHART
&&

.AVIATION...
ISSUED 503 AM CST SAT NOV 24 2012

AUTEN
&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS LINCOLN IL

226 AM CST SAT NOV 24 2012

.DISCUSSION...
ISSUED 225 AM CST SAT NOV 24 2012

THE PRIMARY FORECAST CONCERN INVOLVES THE PRECIPITATION POTENTIAL
MONDAY AND MONDAY NIGHT...INCLUDING ANY WINTER PRECIP TYPES...AS A
STORM SYSTEM PASSES TO OUR SOUTH.

SHORT TERM...TODAY THROUGH MONDAY NIGHT...

LONG TERM...TUESDAY THROUGH FRIDAY...

GEELHART

.AVIATION...
ISSUED 1149 PM CST FRI NOV 23 2012

MVFR CEILINGS CURRENTLY OVER NORTHERN ILLINOIS HAVE BEEN CREEPING
SLOWLY SOUTHWARD THIS EVENING AND ARE NOW NEARING THE I-74 TERMINALS.
CLOUDS ARE BEING PUSHED SOUTHWARD AS A RESULT OF N/NW FLOW ON THE
BACK SIDE OF A DEPARTING UPPER LOW OVER QUEBEC. GIVEN N/NW FLOW
NOTED ON AREA VAD WIND PROFILERS AND CURRENT SATELLITE TRENDS...HAVE
ADDED A PERIOD OF LOW VFR CEILINGS OF 3500FT AT BOTH KBMI AND
KCMI BETWEEN 06Z AND 11Z. CLOUDS WILL DROP S/SE...THEN GRADUALLY
SHIFT EASTWARD EARLY SATURDAY MORNING AS UPPER LOW PULLS FURTHER
AWAY. SKIES WILL THEN BE MOSTLY CLEAR ACROSS THE BOARD...UNTIL
MID/HIGH CLOUDS INCREASE FROM THE WEST DURING THE AFTERNOON/EVENING.
MODELS HAVE BEEN SUGGESTING A PERIOD OF WARM ADVECTION TYPE CLOUDS
AOA 9000FT SPREADING INTO KPIA AND KSPI BY AROUND 18Z...THEN
FURTHER EAST TO KCMI BY 21Z. WINDS WILL INITIALLY BE FROM THE
NORTHWEST AT 5 TO 10KT TONIGHT INTO SATURDAY MORNING...THEN WILL
BACK TO THE SOUTH BY EVENING.

BARNES
&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

545 PM EST SAT NOV 24 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.

.SYNOPSIS...
ISSUED AT 324 PM EST SAT NOV 24 2012

DRY CONDITIONS WILL PERSIST INTO MONDAY AS HIGH PRESSURE PASSES TO
THE SOUTH OF THE REGION. A SURFACE LOW WILL TRACK ALONG A REMNANT
COLD FRONT THROUGH THE TENNESSEE VALLEY MONDAY NIGHT. MOISTURE
ASSOCIATED WITH THE LOW WILL LOFT INTO THE REGION...BRINGING CLOUDS
AND LIGHT RAIN CHANGING TO SNOW. COLD DRY WEATHER WILL RETURN FOR
MUCH OF THE REST OF THE WEEK AS BROAD HIGH PRESSURE BUILDS ACROSS
THE OHIO VALLEY.

.NEAR TERM /TONIGHT/...

ISSUED AT 324 PM EST SAT NOV 24 2012

TEMPS HAVE BEEN HELD DOWN SO FAR TODAY AS EXTENSIVE STRATOCU DECK
REMAINS ACROSS MOST OF THE FORECAST AREA. AT 19Z...TEMPERATURES
RANGED FROM THE UPPER 20S TO LOWER 30S ACROSS THE REGION.

STRATOCU DECK IS THE INITIAL FOCUS OF THE FORECAST. VISIBLE
SATELLITE SHOWING EROSION OF THE STRATOCU ACROSS THE WABASH VALLEY
OVER THE LAST HOUR OR TWO AS LOW LEVEL FLOW BACKING IN RESPONSE TO
THE ARRIVAL OF THE RIDGE AXIS. EXPECT LOW CLOUDS TO GRADUALLY THIN
FROM THE WEST THROUGH THE REMAINDER OF THE AFTERNOON WITH SOME
SUNSHINE ANTICIPATED WEST OF I-65 PRIOR TO SUNSET. FURTHER
EAST...STRATOCU APPEARS MORE FIRMLY ENTRENCHED ON BACK SIDE OF DEEP
UPPER TROUGH. HAVE TRENDED TOWARDS RAP 900-925MB RH PROGS WHICH KEEP
CLOUDS INTO THE EVENING BEFORE THEY GIVE WAY FROM THE WEST.

ANY CLEARING HOWEVER IS LIKELY TO BE TEMPORARY ACROSS THE FORECAST
AREA AS MID AND HIGH LEVEL CLOUDS ARE ALREADY RAPIDLY EXPANDING EAST
ACROSS THE MID MISSISSIPPI VALLEY AND WILL ENCOMPASS THE REGION
OVERNIGHT. DEEP MOISTURE PRESENT ABOVE 600MB AFTER MIDNIGHT WITH
ISENTROPIC LIFT NOTED AT 300K AND HIGHER ALL SUGGESTIVE OF FAIRLY
DENSE CLOUD COVER LATE TONIGHT...ESPECIALLY OVER THE NORTHERN HALF
OF THE FORECAST AREA.

TEMPS...ENDED UP NEAR MAVMOS FOR LOWS OVERNIGHT AS COOLER THAN
EXPECTED TEMPS TODAY COUNTERACT POTENTIAL FOR TEMPS TO STAY UP WITH
CLOUDS TONIGHT. SHOULD END UP IN THE MID 20S MOST PLACES OVERNIGHT.

.SHORT TERM /SUNDAY THROUGH TUESDAY/...

ISSUED AT 324 PM EST SAT NOV 24 2012

FORECAST CHALLENGES FOCUS ON PRECIP CHANCES AND TYPE WITH SURFACE
WAVE TRACKING THROUGH THE TENNESSEE VALLEY MONDAY NIGHT.

COLD FRONT WILL DROP SOUTH INTO THE REGION DURING THE DAY SUNDAY...
MAINTAINING MID AND HIGH LEVEL CLOUDS ACROSS THE NORTHERN HALF OF
THE FORECAST AREA. MODEL SOUNDINGS CONTINUE TO SHOW AN AXIS OF DEEP
MOISTURE ABOVE 10KFT AHEAD OF THE FRONT...GRADUALLY SHIFTING NORTH
BY LATE AFTERNOON AND EVENING AS MOISTURE PROFILES DECREASE AND
BOUNDARY LOSES ITS SURFACE CHARACTERISTICS AS IT SLIDES SOUTH.

WHATS LEFT OF THE BOUNDARY WILL SHIFT SOUTH OF THE OHIO RIVER ON
MONDAY AND BECOME NEARLY STATIONARY AS A SURFACE WAVE DEVELOPS OVER
TEXAS AND TRACKS NORTHEAST ALONG IT. MODEL CONSENSUS OVER THE LAST
COUPLE DAYS CONTINUE TO SHIFT THE TRACK OF THE LOW AND POSITION OF
THE BOUNDARY STEADILY SOUTH INTO THE TENNESSEE VALLEY BY LATE
MONDAY...LIKELY DUE AS MODELS CAPTURE THE STRENGTH OF THE
APPROACHING HIGH OVER THE NORTHERN PLAINS TO A GREATER DEGREE. THE
FURTHER SOUTH TRACK TO THIS SYSTEM IS PRESENTING SOME CHANGES NOT
ONLY IN THE AMOUNT OF PRECIPITATION BUT ALSO IN POTENTIAL PRECIP
TYPE AS COLDER AIR FILTERS INTO CENTRAL INDIANA MUCH QUICKER ON
MONDAY NIGHT.

HAVE LEANED TOWARDS THE CONSENSUS APPROACH BEING OFFERED BY THE
ECMWF/OP GFS/SREF WHICH BRING THE MOISTURE PLUME NORTH INTO THE OHIO
VALLEY LATE MONDAY AFTERNOON AHEAD OF THE UPPER LEVEL TROUGH AND
NORTH OF THE SURFACE WAVE...SPREADING EAST ACROSS THE REGION MONDAY
NIGHT. BEST ISENTROPIC LIFT NOW CONFINED TO MAINLY SOUTHERN PORTIONS
OF THE FORECAST AREA MONDAY NIGHT...AND EXPECT THE MOST WIDESPREAD
PRECIPITATION WILL SET UP FROM FAR SOUTHERN COUNTIES SOUTH INTO
KENTUCKY. FURTHER NORTH WHERE MOISTURE PROFILES ARE NOT AS
IMPRESSIVE...EXPECT LIGHTER PRECIP TO THE TUNE OF LESS THAN A TENTH
OF AN INCH. ANALYSIS OF MODEL SOUNDINGS AND LOW LEVEL THICKNESSES
SUGGESTIVE OF MAINLY LIGHT SNOW ALONG AND NORTH OF I-70 MONDAY
EVENING...WITH RAIN GRADUALLY MIXING WITH AND CHANGING OVER TO LIGHT
SNOW FURTHER SOUTH AS THE NIGHT WEARS ON. SOME HINTS OF A BAND OF
ENHANCED PRECIP SETTING UP NEAR OR JUST SOUTH OF THE FORECAST AREA
LATE MONDAY NIGHT AND SHOULD THE COLDER AIR ARRIVE FAST ENOUGH...
COULD SEE A QUICK BURST OF SNOW WITH A POSSIBLE ACCUM OF A FEW
TENTHS ACROSS FAR SOUTHERN COUNTIES BEFORE THE BETTER LIFT SHIFTS
EAST AROUND DAYBREAK TUESDAY. WITH THE CONSISTENT SHIFT SOUTH OF THE
TRACK OF THE SURFACE LOW THE LAST FEW DAYS...CONFIDENCE IS LOW ON
WHETHER THAT BAND OF ENHANCED PRECIP WILL SET UP OVER FAR SOUTHERN
COUNTIES OR IF ITS CLOSER TO THE OHIO RIVER. ANY LINGERING PRECIP
WILL END TUESDAY MORNING AS THE BROAD HIGH PRESSURE SHIFTS EAST INTO
THE REGION. COLD DRY WEATHER WILL THEN RESUME FOR CENTRAL INDIANA
FOR MIDWEEK.

TEMPS...LEANED TOWARDS COOLER MAVMOS FOR SUNDAY WITH POTENTIAL FOR
MORE CLOUDS ACROSS THE REGION. UNDERCUT MOS ON MONDAY WITH
INCREASING CLOUDS AND NORTHERLY FLOW AND AGAIN TUESDAY WITH COLD
ADVECTION IN WAKE OF THE STORM SYSTEM. NEAR MOS FOR LOWS TONIGHT...
THEN WENT ABOVE GUIDANCE FOR MONDAY NIGHT WITH MOS APPEARING TO
OVERDO THE COLD AIR INTRUSION.

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...

ISSUED AT 324 PM EST SAT NOV 24 2012

HIGH PRESSURE WILL BE IN CONTROL FOR THE MAJORITY OF THE EXTENDED
PERIOD RESULTING IN A COOL/DRY AIRMASS OVER CENTRAL INDIANA. TEMPS
WILL GRADUALLY WARM THROUGH THE COURSE OF THE PERIOD...AND
INITIALIZATION HAS A GOOD HANDLE ON IT...SO NO DEVIATIONS.
INITIALIZATION IS HINTING AT SOME PRECIP OVER THE NORTHERN PORTIONS
OF THE FORECAST AREA AT THE END OF THE PERIOD AS AN UPPER LEVEL
SHORTWAVE TRAVERSES CENTRAL INDIANA. THERE ARE A LOT OF
DISCREPANCIES IN THE MODELS AT THIS TIME THOUGH...SO WILL NOT MAKE
ANY CHANGES TO LATEST PRECIP INITIALIZATION. THE EURO AND GEM BARELY
HINT AT THE SHORTWAVE ON THURSDAY NIGHT/FRIDAY MORNING...WHILE
THE GFS SHOWS A SOMEWHAT DEVELOPED UPPER LEVEL LOW.

.AVIATION /DISCUSSION FOR THE 25/0000Z TAF ISSUANCE/...

ISSUED AT 545 PM EST SAT NOV 24 2012

STRATOCU DECK SHOULD BE NORTHEAST OF THE TAF SITES BY ISSUANCE TIME
PER MODEL 925 MILLIBAR RH PROGS. MEANWHILE...THICK HIGH AND MID
CLOUDS WILL ALSO BE MOVING IN FROM THE WEST AND COVER THE SKY
THROUGH THE REMAINDER OF THE TAF PERIOD. SOUTH AND SOUTHWEST WINDS 5
KNOTS OR LESS WILL INCREASE TO NEAR 10 KNOTS TOWARD 12Z AND 15 KNOTS
AFTER 15Z WITH GUSTS TO 20 KNOTS OR MORE. WINDS WILL THEN DIMINISH
TO LESS THAN 10 KNOTS AND BECOME SOUTHWEST AND WEST AFTER 21Z BEHIND
A DRY COLD FRONT.

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....TDUD
AVIATION...MK

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

330 PM EST SAT NOV 24 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.

.SYNOPSIS...
ISSUED AT 324 PM EST SAT NOV 24 2012

.NEAR TERM /TONIGHT/...

ISSUED AT 324 PM EST SAT NOV 24 2012

TEMPS HAVE BEEN HELD DOWN SO FAR TODAY AS EXTENSIVE STRATOCU DECK
REMAINS ACROSS MOST OF THE FORECAST AREA. AT 19Z...TEMPERATURES
RANGED FROM THE UPPER 20S TO LOWER 30S ACROSS THE REGION.

TEMPS...ENDED UP NEAR MAVMOS FOR LOWS OVERNIGHT AS COOLER THAN
EXPECTED TEMPS TODAY COUNTERACT POTENTIAL FOR TEMPS TO STAY UP WITH
CLOUDS TONIGHT. SHOULD END UP IN THE MID 20S MOST PLACES OVERNIGHT.

.SHORT TERM /SUNDAY THROUGH TUESDAY/...

ISSUED AT 324 PM EST SAT NOV 24 2012

FORECAST CHALLENGES FOCUS ON PRECIP CHANCES AND TYPE WITH SURFACE
WAVE TRACKING THROUGH THE TENNESSEE VALLEY MONDAY NIGHT.

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...

ISSUED AT 324 PM EST SAT NOV 24 2012

.AVIATION /DISCUSSION FOR THE 24/2100Z TAF UPDATE/...

ISSUED AT 330 PM EST SAT NOV 24 2012

PERSISTENT STRATOCU DECK IS KEEPING CEILINGS AT MVFR CATEGORY AT THE
SITES AND SHOULD REMAIN THAT WAY THROUGH LATE AFTERNOON /23Z/ WHEN
THE CLOUDS SHOULD SCATTER OUT AND RETURN TO VFR CONDITIONS. AS LOW
LEVEL CLOUDS START TO SCATTER...HIGH CLOUDS WILL THEN START
FILTERING INTO TAF SITES THIS EVENING AHEAD OF AN APPROACHING COLD
FRONT. THIS WILL NOT IMPACT TAF SITES THOUGH...AND CONDITIONS WILL
REMAIN AT VFR CATEGORY FOR THE REMAINDER OF TAF PERIOD. WINDS WILL
BACK TO THE SOUTHWEST THIS EVENING AND BE SUSTAINED AT 3 TO 6 KTS.

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....TDUD
AVIATION...TDUD/CP

AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

324 PM EST SAT NOV 24 2012

.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW.

.SYNOPSIS...
ISSUED AT 324 PM EST SAT NOV 24 2012

.NEAR TERM /TONIGHT/...

ISSUED AT 324 PM EST SAT NOV 24 2012

TEMPS HAVE BEEN HELD DOWN SO FAR TODAY AS EXTENSIVE STRATOCU DECK
REMAINS ACROSS MOST OF THE FORECAST AREA. AT 19Z...TEMPERATURES
RANGED FROM THE UPPER 20S TO LOWER 30S ACROSS THE REGION.

TEMPS...ENDED UP NEAR MAVMOS FOR LOWS OVERNIGHT AS COOLER THAN
EXPECTED TEMPS TODAY COUNTERACT POTENTIAL FOR TEMPS TO STAY UP WITH
CLOUDS TONIGHT. SHOULD END UP IN THE MID 20S MOST PLACES OVERNIGHT.

.SHORT TERM /SUNDAY THROUGH TUESDAY/...

ISSUED AT 324 PM EST SAT NOV 24 2012

FORECAST CHALLENGES FOCUS ON PRECIP CHANCES AND TYPE WITH SURFACE
WAVE TRACKING THROUGH THE TENNESSEE VALLEY MONDAY NIGHT.

HAVE LEANED TOWARDS THE CONSENSUS APPROACH BEING OFFERED BY THE
ECMWF/OP GFS/SREF WHICH BRING THE MOISTURE PLUME NORTH INTO THE OHIO
VALLEY LATE MONDAY AFTERNOON AHEAD OF THE UPPER LEVEL TROUGH AND
NORTH OF THE SURFACE WAVE...SPREADING EAST ACROSS THE REGION MONDAY
NIGHT. BEST ISENTROPIC LIFT NOW CONFINED TO MAINLY SOUTHERN PORTIONS
OF THE FORECAST AREA MONDAY NIGHT...AND EXPECT THE MOST WIDESPREAD
PRECIPITATION WILL SET UP FROM FAR SOUTHERN COUNTIES SOUTH INTO
KENTUCKY. FURTHER NORTH WHERE MOISTURE PROFILES ARE NOT AS
IMPRESSIVE...EXPECT LIGHTER PRECIP TO THE TUNE OF LESS THAN A TENTH
OF AN INCH. ANALYSIS OF MODEL SOUNDINGS AND LOW LEVEL THICKNESSES
SUGGESTIVE OF MAINLY LIGHT SNOW ALONG AND NORTH OF I-70 MONDAY
EVENING...WITH RAIN GRADUALLY MIXING WITH AND CHANGING OVER TO LIGHT
SNOW FURTHER SOUTH AS THE NIGHT WEARS ON. SOME HINTS OF A BAND OF
ENHANCED PRECIP SETTING UP NEAR OR JUST SOUTH OF THE FORECAST AREA
LATE MONDAY NIGHT AND SHOULD THE COLDER AIR ARRIVE FAST ENOUGH...
COULD SEE A QUICK BURST OF SNOW WITH A POSSIBLE ACCUM OF A FEW TENTHS
ACROSS FAR SOUTHERN COUNTIES BEFORE THE BETTER LIFT SHIFTS EAST
AROUND DAYBREAK TUESDAY. WITH THE CONSISTENT SHIFT SOUTH OF THE
TRACK OF THE SURFACE LOW THE LAST FEW DAYS...CONFIDENCE IS LOW ON
WHETHER THAT BAND OF ENHANCED PRECIP WILL SET UP OVER FAR SOUTHERN
COUNTIES OR IF ITS CLOSER TO THE OHIO RIVER. ANY LINGERING PRECIP
WILL END TUESDAY MORNING AS THE BROAD HIGH PRESSURE SHIFTS EAST INTO
THE REGION. COLD DRY WEATHER WILL THEN RESUME FOR CENTRAL INDIANA
FOR MIDWEEK.

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...

ISSUED AT 324 PM EST SAT NOV 24 2012

.AVIATION /DISCUSSION FOR THE 24/1800Z TAF ISSUANCE/...

ISSUED AT 1230 PM EST SAT NOV 24 2012

PERSISTENT STRATOCU DECK IS KEEPING CEILINGS AT MVFR CATEGORY AT
KBMG AND KHUF AND SHOULD REMAIN THAT WAY THROUGH LATE AFTERNOON.
AFTER THAT...KBMG AND KHUF WILL RETURN TO VFR CONDITIONS.
MEANWHILE...KIND AND KLAF HAVE ALREADY REACHED VFR CATEGORY BUT
REMAIN OVERCAST. AS LOW LEVEL CLOUDS START TO SCATTER...HIGH
CLOUDS WILL THEN START FILTERING INTO TAF SITES THIS EVENING AHEAD
OF AN APPROACHING COLD FRONT. THIS WILL NOT IMPACT TAF SITES
THOUGH...AND CONDITIONS WILL REMAIN AT VFR CATEGORY FOR THE
REMAINDER OF TAF PERIOD. WINDS WILL BACK TO THE SOUTHWEST THIS
EVENING AND BE SUSTAINED AT 3 TO 6 KTS.

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....TDUD
AVIATION...TDUD

AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

1221 PM EST SAT NOV 24 2012

.AVIATION...

CEILINGS WILL GRADUALLY IMPROVE THROUGH THE AFTERNOON AS DRIER AIR
WORKS INTO THE REGION AND LOW LEVEL WINDS BACK TO A MORE
SOUTHWESTERLY DIRECTION. THIS WILL TAKE SOME TIME THOUGH WITH
PERSISTENT CYCLONIC FLOW OVER THE AREA. STRATOCU DECK WILL SCATTER
COMPLETELY BY LATE THIS EVENING WITH VFR CONDITIONS CONTINUING
THROUGH THE REST OF THE PERIOD. A PASSING SHORTWAVE TROUGH WILL
BRING AN INCREASE IN MIDLEVEL CLOUDS ASSOCIATED WITH WAA ALOFT BUT
CEILINGS WILL STAY WELL ABOVE 5 KFT.

.PREV DISCUSSION... /ISSUED 1032 AM EST SAT NOV 24 2012/

UPDATE...

LATEST RADAR AND SURFACE OBSERVATIONS SHOW LITTLE MORE THAN
FLURRIES ACROSS THE AREA THIS MORNING THANKS TO IMPRESSIVE DRY AIR
ENTRAINMENT. CEILINGS ARE HOVERING AROUND 2500 FT WITH VERY DRY
AIR ABOVE 5-6 KFT...SEVERELY LIMITING SNOW POTENTIAL. UPDATED
FORECAST TO REMOVE ALL POPS AND TO EXPAND FLURRIES IN THE
NORTHEAST. THIS RELATIVELY THIN LAYER OF STRATOCU HAS BEEN SLOW
TO ERODE TO OUR SOUTHWEST THOUGH AND MADE SOME ADJUSTMENTS TO SKY
COVER AS WELL. EXPECT CLOUDS AND FLURRIES WILL CONTINUE UNTIL LATE
THIS AFTERNOON WHEN THE FLOW BECOMES INCREASINGLY ANTICYCLONIC
WITH BUILDING MIDLEVEL HEIGHTS AND LARGE SCALE SUBSIDENCE. ALSO
SHAVED A DEGREE OR TWO OFF HIGH TEMPS OWING TO MORE PESSIMISTIC
CLOUD FORECAST.

PREV DISCUSSION... /ISSUED 341 AM EST SAT NOV 24 2012/

SHORT TERM...
FAILED LES RESPONSE ALG WRN PERIPHERY OF LK MI SO FAR OWING TO
DEGREE OF DRY ENTRAINMENT ONGOING OUT OF WI. MOST FVRBL LK SP FETCH
PRECONDITIONING 2 INTENSE BANDS ACRS NRN LWR STRETCHING SEWD INTO
THE THUMB. SOME INDICATION IN RECENT RADAR IMAGERY OF WK BANDING
DVLPG ALG A KMKG-KBIV LINE AND IF THAT INDEED DVLPS AS RUC SOLUTIONS
SUGGEST THAT CONTD SHALLOW BNDRY LYR VEERING SHLD ALLOW THAT TO SAG
SWD THROUGH MID MORNING. HWVR GIVEN THE DEARTH OF ADDNL MSTR ALOFT
WILL BACK POPS OFF CONSIDERABLY.

OTHERWISE CONTD QUITE COLD TDA W/LG AREA OF STRATO CU LOCKED IN
BENEATH FAIRLY SHARP LL INVERSION. FLW BACKS LT AFTN WHICH WILL
ERODE SWRN EDGE AND PROMOTE LIMITED INSOLATION BUT CONSIDERED TOO
LATE TO APPRECIABLE PROMOTE MORE OF A DIURNAL RESPONSE. GREATER CLRG
XPCD GOING INTO THIS EVENING AHD OF INCOMING HIGH CLD SHIELD
ASSOCD/W FAST MOVING DISTURBANCE OVR SWRN CANADA. LOSS OF DEEPER SC
UNDERNEATH ENVELOPING BUT THIN HIGH CLD SHIELD PERPLEXING GIVEN COLD
MOS GUIDANCE IN LIGHT OF SWRLY RTN FLW DVLPG ON BACKSIDE OF
DEPARTING RIDGE AXIS. THUS WILL ONLY MAKE SLIGHT ADJUSTMENTS FOR
TYPICAL LOCAL COLD SPOTS.

UPSTREAM SYS WILL DEAMPLIFY QUICKLY SEWD ON SUN. WAA AHD OF THIS FTR
AND PARTIAL SUN WILL YIELD A BTR DIURNAL RESPONSE W/ANTICIPATED
GREATER MIXING AND GAVE A +1 BUMP HIGHER.

LONG TERM...MONDAY THROUGH FRIDAY

MAIN FOCUS REMAINS ON DWINDLING CHANCES FOR SNOW WITH SYSTEM NOW
PROGGED TO TRACK THROUGH THE TN/OH VALLEYS LATE MONDAY AFTERNOON
THROUGH TUESDAY MORNING. 12/00Z GFS/GEFS/GEM ITERATIONS HAVE ALL
TRENDED TOWARD THE LESS AMPLIFIED AND THEREFORE FARTHER SOUTH
SOLUTION OF THE ECMWF WITH A SFC LOW TRACK FROM THE SOUTHERN PLAINS
EAST THROUGH THE TN VALLEY. THIS SOUTHERLY TRACK WOULD RESULT IN
DRY/COLD CONDITIONS LOCALLY WITH SFC HIGH PRESSURE BUILDING INTO THE
SOUTHERN GREAT LAKES. HOWEVER...WOULD NOT BE SURPRISED TO SEE MODELS
TREND BACK A LITTLE TO THE NORTH AND MORE AMPLIFIED WITH THIS
POSITIVE PV ANOMALY AS IT DROPS SOUTHEAST INTO THE MIDWEST. INITIAL
PROGRESSIVE POSITIVE TILT AND CONFLUENCE ACROSS THE LAKES WILL KEEP
IT FROM MAKING IT TOO FAR NORTH BUT CANNOT RULE OUT NORTHERN FRINGE
OF PCPN SHIELD CLIPPING OUR AREA. GUIDANCE OFTEN WEAKENS OR LOSES A
STORM IN THE 4-5 DAY PERIOD ONLY TO LATCH BACK ONTO A STRONGER
SOLUTION WITHIN 72 HOURS AS WAVE FINALLY REACHES OUR RADIOSONDE
NETWORK. HAVE BEEN BURNT BY THIS SEVERAL TIMES SO OPTED TO RETAIN
LOWER CHANCE POPS MAINLY MONDAY NIGHT...HIGHEST SOUTH. THIS WILL
NEED TO BE MONITORED CLOSELY GIVEN PROSPECTS FOR A NARROW SWATH OF
ACCUMULATING SNOW ON THE NORTHERN FLANK OF THIS SYSTEM.

ATTENTION FOR THE MID TO LATE WEEK PERIOD WILL TURN TO TEMPERATURES
AND CLOUD COVER. TOUGH FORECAST AS AREA LIKELY TO BE NEAR A FRONTAL
BOUNDARY ON THE SOUTHWESTERN FRINGE OF A RETREATING POLAR
JET...ESPECIALLY BY THURSDAY AND FRIDAY. A DEVELOPING NEGATIVE
NAO/AO WILL HELP MAINTAIN NORTH ATLANTIC/EASTERN CANADA
BLOCKING...WHILE -PNA AND NORTHEAST PACIFIC NEGATIVE HEIGHT ANOMALY
ALLOW RIDGING/WARMTH TO OVERSPREAD THE PLAINS/MIDWEST. WE`LL BE IN
BETWEEN MAKING IT A DIFFICULT FORECAST. GIVEN THE UNCERTAINTIES
OPTED TO LOAD AND GO WITH THE 00Z ALLBLEND WHICH DOESN`T LOOK TOO
BAD AT THIS POINT WITH TEMPS TRENDING UP TO NEAR NORMAL BY
THURSDAY/FRIDAY. CLOUDS WITH ANY MOISTURE STARVED (LOW AMPLITUDE)
SHORTWAVES IN WNW FLOW WILL ALSO IMPACT TEMPS...ESPECIALLY LATE
THURSDAY INTO FRIDAY PER A ECMWF/GFS/GEFS COMPROMISE. GUIDANCE ALSO
PRINTING OUT SOME LIGHT QPF WITH THIS WAVE BUT WILL HOLD OFF ADDING
ANY POPS GIVEN TIMING DIFFERENCES AND LACK OF MOISTURE/FORCING WITH
SHEARED WAVE(S).

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR LMZ043-046.

SHORT TERM...T
LONG TERM...STEINWEDEL
AVIATION...AGD
UPDATE...AGD

AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

1032 AM EST SAT NOV 24 2012

.UPDATE...

.PREV DISCUSSION... /ISSUED 341 AM EST SAT NOV 24 2012/

UPSTREAM SYS WILL DEAMPLIFY QUICKLY SEWD ON SUN. WAA AHD OF THIS FTR
AND PARTIAL SUN WILL YIELD A BTR DIURNAL RESPONSE W/ANTICIPATED
GREATER MIXING AND GAVE A +1 BUMP HIGHER.

LONG TERM...MONDAY THROUGH FRIDAY

AVIATION...
MVFR CONDS THIS MORNING WILL GRADUALLY IMPROVE INTO THIS AFTN
W/CONTD LL DRY ENTRAINMENT. SIG SHSN AT KSBN LOOKING MORE AND MORE
DOUBTFUL AND WILL MOST LIKELY BE DROPPED W/12Z ISSUANCE AS DRY AIR
CLEARLY WINNING OUT SO FAR.

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR LMZ043-046.

SHORT TERM...T
LONG TERM...STEINWEDEL
AVIATION...T
UPDATE...AGD

AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

341 AM EST SAT NOV 24 2012

.SHORT TERM...
FAILED LES RESPONSE ALG WRN PERIPHERY OF LK MI SO FAR OWING TO
DEGREE OF DRY ENTRAINMENT ONGOING OUT OF WI. MOST FVRBL LK SP FETCH
PRECONDITIONING 2 INTENSE BANDS ACRS NRN LWR STRETCHING SEWD INTO
THE THUMB. SOME INDICATION IN RECENT RADAR IMAGERY OF WK BANDING
DVLPG ALG A KMKG-KBIV LINE AND IF THAT INDEED DVLPS AS RUC SOLUTIONS
SUGGEST THAT CONTD SHALLOW BNDRY LYR VEERING SHLD ALLOW THAT TO SAG
SWD THROUGH MID MORNING. HWVR GIVEN THE DEARTH OF ADDNL MSTR ALOFT
WILL BACK POPS OFF CONSIDERABLY.

UPSTREAM SYS WILL DEAMPLIFY QUICKLY SEWD ON SUN. WAA AHD OF THIS FTR
AND PARTIAL SUN WILL YIELD A BTR DIURNAL RESPONSE W/ANTICIPATED
GREATER MIXING AND GAVE A +1 BUMP HIGHER.

.LONG TERM...MONDAY THROUGH FRIDAY

.AVIATION...
MVFR CONDS THIS MORNING WILL GRADUALLY IMPROVE INTO THIS AFTN
W/CONTD LL DRY ENTRAINMENT. SIG SHSN AT KSBN LOOKING MORE AND MORE
DOUBTFUL AND WILL MOST LIKELY BE DROPPED W/12Z ISSUANCE AS DRY AIR
CLEARLY WINNING OUT SO FAR.

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR LMZ043-046.

SHORT TERM...T
LONG TERM...STEINWEDEL
AVIATION...T

AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

548 PM EST SAT NOV 24 2012

.SYNOPSIS...
SNOW CURRENTLY AFFECTING A LARGE PORTION OF THE FORECAST AREA WILL
DIMINISH TONIGHT. TEMPERATURES WILL REMAIN BELOW NORMAL THROUGH THE
WEEK...WITH THE NEXT CHANCE FOR SNOW COMING MONDAY NIGHT INTO
TUESDAY.

.NEAR TERM /THROUGH SUNDAY/...
INVERSION HEIGHTS PER THE NAM AND RAP ARE ALREADY FALLING OFF THIS
EVENING DOWNWIND OF LAKE ERIE. THEY STARTED OUT ABOVE 8 KFT
EARLIER...AND SHOULD FALL TOWARD 5 KFT WITHIN THE NEXT FEW HOURS.
WHILE INSTABILITY IS STILL RATHER IMPRESSIVE GIVEN LAKE
TEMPERATURES AROUND +7 TO +8C AND MODEL 850 MB TEMPERATURES AROUND
-11C...THE LENGTH OF FETCH OVER THE LAKE AS WELL AS UPSTREAM
ANTECEDENT CONDITIONS REALLY ARE NOT. BOUNDARY LAYER DEWPOINTS
NORTH OF LAKE HURON ARE RUNNING NEAR 10F...WHILE IS YIELDING
DEWPOINT DEPRESSIONS OF 10-20F IN SOUTHERN ONTARIO. THIS IS JUST A
BIT TOO DRY TO GET LAKE EFFECT HUMMING ALONG WITHOUT MULTI-LAKE
FLOW CONDITIONS. AS IT STANDS...WE NEVER FULLY GOT A MULTI-LAKE
CONNECTION BETWEEN LAKE HURON AND LAKE ERIE TO GET THE BANDING
GOING OVER OUR AREA AS THE LOW LEVEL FLOW COMPONENT WAS A BIT TOO
WESTERLY. AS A RESULT...WHILE WIDESPREAD SNOW SHOWERS DID STILL
OCCUR...THE BANDING THAT FLOWED OVER MORE THAN ONE LAKE REMAINED
MAINLY IN NORTHERN LOWER MICHIGAN (SUPERIOR/MICHIGAN) AND UPSTATE
NEW YORK (HURON/ERIE). AS LOW LEVEL FLOW BACKS AGAIN TONIGHT IN
RESPONSE TO ANOTHER SHORT WAVE DIVING SOUTHWARD...THIS SHOULD EVEN
BRING THE SNOW SHOWERS AND FLURRIES WE HAVE AROUND THIS EVENING TO
AN END.

BECAUSE OF THE AFOREMENTIONED PROBLEMS FOR MODERATE SNOWFALL
ACCUMULATIONS...THE LAKE EFFECT SNOW ADVISORY HAS BEEN DROPPED.
ANY ENHANCED BANDS THAT MAY PERK UP THIS EVENING WILL BE HANDLED
WITH SPECIAL WEATHER STATEMENTS...HOWEVER THE LIKELIHOOD OF
STRONGER BANDS IS DECREASING BY THE HOUR ACROSS THE AREA. FRIES

PREVIOUS DISCUSSION ABOUT TOMORROW FOLLOWS...
A SHORTWAVE IS EXPECTED TO SPEED TO THE EAST TOMORROW...RACING
FROM LOWER MICHIGAN IN THE MORNING TO NEW JERSEY IN THE EVENING.
OVER THE LAST FEW DAYS...MODELS HAVE VERY GRADUALLY INTENSIFIED
THE SHORTWAVE IN ADDITION TO BRINGING IT FARTHER TO THE SOUTH.
APPEARS THAT ANY PRECIPITATION ASSOCIATED WITH THE SHORTWAVE WILL
JUST GLANCE THE LOCAL FORECAST AREA...AND ALTHOUGH POPS COME A BIT
FARTHER SOUTH THAN PREVIOUS FORECAST...HAVE NOT GONE MUCH FARTHER
SOUTH THAN INTERSTATE 80. EXPECT SOME MINOR IMPROVEMENT IN HIGH
TEMPERATURES COMPARED TO TODAY WITH SOUTHWESTERLY WINDS AT 10-15
MPH...BUT TEMPERATURES WILL STILL BE SEVERAL DEGREES BELOW NORMAL.

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
WEAK HIGH PRESSURE WILL MOVE INTO THE SOUTHEASTERN UNITED
STATES...ALLOWING FOR AT LEAST ONE DAY OF DRY WEATHER FOR ALL
COUNTIES SUNDAY NIGHT INTO MONDAY. MODELS THEN FOLLOW THE HIGH
PRESSURE WITH A CYCLONE...WITH MUCH OF THE PRECIPITATION FALLING
TO THE NORTH OF THE SURFACE LOW. MODELS HAVE BEEN QUITE
INCONSISTENT WITH THE STORM DURING THE LAST COUPLE OF DAYS...AND
THEREFORE HAVE DECIDED NOT TO MAKE ANY MAJOR CHANGES TO THIS
PORTION OF THE FORECAST. MADE SOME SLIGHT TWEAKS WITH TIMING OF
SYSTEM...BUT OTHERWISE WILL KEEP GENERAL FORECAST OF CHANCE
POPS...WITH SOME LIKELY POPS CREEPING INTO THE RIDGES. ANY
PRECIPITATION IS EXPECTED TO START AS SNOW MONDAY NIGHT...WITH
MOST PLACES CHANGING OVER TO RAIN ON TUESDAY. TEMPERATURES WILL
REMAIN BELOW NORMAL.

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A CHANCE OF A RAIN SNOW MIX OVER MOST OF THE REGION TUESDAY NIGHT
INTO WEDNESDAY AS SURFACE LOW MOVES TOWARD THE UPPER OHIO VALLEY.
THIS SYSTEM THEN MOVES EASTWARD BY WEDNESDAY WITH ANOTHER SHOT OF
NORTHWEST FLOW AGAIN BRINGING THE CHANCE FOR A SHORT PERIOD OF
LAKE EFFECT SNOW FLURRIES AND SHOWERS. THEN BY WEDNESDAY NIGHT DRY
AND CONTINUED SEASONABLE THROUGH SATURDAY.

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
MVFR CONDS EXPECTED THRU EARLY TONIGHT...WITH LAKE EFFECT SNOW
SHOWERS OCCURRING AT MOST TERMINALS EXCEPT ZZV. IMPROVEMENT TO VFR
CONDITIONS OVERNIGHT. WINDS WILL TURN MORE WEST AS SURFACE RIDGE
SHIFTS EAST OVERNIGHT.

.OUTLOOK.../SUNDAY THROUGH THURSDAY/...
A CLIPPER MOVING THROUGH THE REGION AHEAD OF NEXT SYSTEM WILL
BRING CLOUDS FROM OVERRUNNING SUNDAY. CHANCE FOR MVFR/IFR WITH
RAIN/SNOW LATE MONDAY INTO TUESDAY...LINGERING IN THE NORTHERN
AREAS WEDNESDAY. CONDITIONS SHOULD DRY OUT BY THURSDAY.

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

1010 PM EST SUN NOV 25 2012

.UPDATE...
ISSUED AT 1010 PM EST SUN NOV 25 2012

OVERALL...GOING FCST APPEARS TO BE IN GOOD SHAPE. UPSTREAM 00Z KINL
SOUNDING SHOWED MOIST LOW LEVELS UP TO AROUND 800MB...BUT WITH SHARP
INVERSION AT 850MB. 850MB TEMP WAS -20C WHICH WILL MEAN THAT AS THE
NIGHT WEARS ON...THE DGZ WILL INTERSECT A GOOD PORTION OF THE
CONVECTIVE LAYER...LEADING TO HIGHER SNOW-TO-WATER RATIOS. THERE ARE
A COUPLE OF FCST CONCERNS. FIRST...CONVERGENCE OVER WRN LAKE
SUPERIOR HAS LED TO MORE PERSISTENT LES OVER NE ONTONAGON COUNTY
ACROSS CNTRL/SRN HOUGHTON COUNTY INTO BARAGA COUNTY. OPTED TO
INCLUDE SRN HOUGHTON COUNTY IN LES ADVY WITH FOCUS ALONG M-38.
CONSIDERED ADDING BARAGA COUNTY...BUT SO FAR...WHILE LES HAS BEEN
MORE PERSISTENT...REFLECTIVITIES AREN`T EXCEEDING 28DBZ...AND THE
POCKETS OF HEAVIER SNOW HAVE BEEN TRANSIENT. RAISED 12HR SNOW
ACCUMULATIONS TO 2-4 INCHES (UNDER ADVY CRITERIA FOR LES). FARTHER
S...NOT MUCH HAS BEEN GOING ON ACROSS THE REST OF ONTONAGON/GOGEBIC
COUNTIES. WITH WINDS VEERING A LITTLE MORE TO THE NW OVER WRN LAKE
SUPERIOR...LES SHOULD PICK UP IN THIS AREA DURING THE NIGHT. LAND
BREEZE COMPONENT TO WIND SHOULD LEAD TO ENHANCED CONVERGENCE/MORE
DOMINANT LES INTO THE AREA BTWN KIWD AND THE PORCUPINE MTNS LATER IN
THE NIGHT.

AS HAS BEEN THE CASE THIS EVENING...THE HEAVIEST SNOW WILL CONTINUE
TO BE FOCUSED OVER THE NE FCST AREA WHERE LAKE INDUCED TROFFING AND
LONGER FETCH WILL LEAD TO HEAVIER SNOW. BUMPED UP SNOW ACCUMULATIONS
BY A COUPLE OF INCHES OVER LUCE COUNTY GIVEN THE PERSISTENCE OF
HEAVIER LES THIS EVENING. COULD BE CLOSE TO WARNING AMOUNTS OVER NRN
PORTIONS OF THE COUNTY. STILL EXPECT HEAVIEST LES TO ORGANIZE LATE
TONIGHT THRU MON AFTN AS SHARPENING SFC TROF DRIFTS S OVER ERN LAKE
SUPERIOR. HIGH RES GUIDANCE STILL POINTS TOWARD ROUGHLY THE E HALF
OF ALGER COUNTY INTO NRN SCHOOLCRAFT FOR GREATEST SNOW TOTALS AS SFC
TROF WILL TEND TO HANG UP IN THAT AREA MON.
&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 428 PM EST SUN NOV 25 2012

WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW
THROUGH THE NRN CONUS. A SHORTWAVE TROUGH EXTENDED FROM NRN ONTARIO
(NEAR CYGQ) INTO NRN WI. A WEAKER UPSTREAM SHRTWV WAS LOCATED OVER
SW MANITOBA. AT THE SFC...LOW PRES WAS LOCATED JUST NORTHEAST OF
LAKE SUPERIOR RESULTING IN WNW LOW LEVEL WINDS. CYCLONIC FLOW AND
ABUNDANT 850-700 MB MOISTURE IN THE WAKE OF THE LOW ALONG WITH 850
MB TEMPS IN THE -11C TO -14C RANGE SUPPORTED AN INCREASE IN LES BAND
INTENSITY. THE STRONGEST BANDS WERE LOCATED NEAR HOUGHTON AND INTO THE
ERN CWA JUST TO THE EAST OF MUNISING.

MAIN FCST CONCERNS ARE LES TRENDS.

EXPECT LES TO CONTINUE FOR LOCATIONS FAVORED BY A 290-310
FLOW...INCLUDING MOST OF THE WRN CWA AND LOCATIONS FROM MUNISING
EASTWARD. THE HIGH RES MODELS IN AGREEMENT SHOWING A GRADUAL
VEERING TREND THIS EVENING WHICH SHOULD HELP TO KEEP THE BANDS FOR
IMPACTING NARROW AREAS FOR AN EXTENDED PERIOD OF TIME. THIS SHOULD
ALSO RESULT IN DECREASING LES INTENSITY INTO THE KEWEENAW WITH A LES
FAVORABLE NW FETCH.

THE HIGH RES MODELS WERE ALSO CONSISTENT IN SHOWING A MORE PRONOUNCED
LOW LEVEL CONV ZONE AIDED BY LAKE INDUCED TROUGHING OVER ERN LAKE
SUPERIOR. THIS SHOULD PROVIDE THE FOCUS FOR THE HEAVIES LES LATE
TONIGHT INTO MONDAY AFTERNOON FOR EASTER ALGER AND NORTHWEST
SCHOOLCRAFT COUNTIES.

INVERSION HEIGHTS IN THE 5K TO 7K FOOT RANGE...GREATEST EAST...ALONG
WITH A DEEP PORTION OF THE CONVECTIVE CLOUDS IN THE DENDRITIC GROWTH
ZONE SHOULD KEEP SNOW/WATER RATIOS IN THE HIGHER SIDE...AT OR ABOVE
20/1. OVERALL SNOWFALL AMOUNTS IN THE 6 TO 12 INCH RANGE STILL LOOK
POSSIBLE FOR SOME LOCATIONS IN ALGER/NSCHOOLCRAFT ZONES WHILE 3 TO 7
INCH AMOUNTS ARE MORE LIKELY OVER THE WEST...GREATEST IN THE HIGHER
TERRAIN BTWN HOUGHTON AND BERGLAND. WITH INVERSION HEIGHTS BEGIN
LOWERING FROM WEST TO EAST MONDAY PREVIOUS FCST TIMING WHICH ENDS
THE LES ADVY OVER THE WEST AT 10 AM LOOKS ON TRACK.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 428 PM EST SUN NOV 25 2012

MON NGT...AS A HI PRES RDG AXIS EXTENDING NEWD FM THE ACYC CENTER IN
THE CENTRAL PLAINS APRCHS...THE LLVL FLOW WL SHIFT STEADILY TO A
MORE WSW DIRECTION. WITH THIS BACKING FLOW...SOME HEAVIER SHSN MIGHT
IMPACT THE KEWEENAW FOR A TIME...BUT LIMITED RESIDENCE TIME WITH
STEADILY SHIFTING WINDS AS WELL AS LOWERING INVRN BASE/WARMING H85
TEMPS SHOULD LIMIT OVERALL ACCUMS. OVER THE E...LLVL CNVGC/LES
INTENSITY MIGHT SHARPEN FOR A TIME WITH BACKING LARGER SCALE
FLOW/LAND BREEZE ENHANCED BY NOCTURNAL COOLING OVER THE CENTRAL
CWA...BUT LES BANDS SHOULD SHIFT OFFSHORE BY 12Z TUE. ALTHOUGH SOME
HEAVIER LES MAY LINGER NEAR THE SHORE FM GRAND MARAIS TO WHITEFISH
POINT LONGER THAN THE 03Z EXPIRATION TIME OF THE GOING LES WARNING
FOR ALGER COUNTY...DID NOT MAKE ANY CHANGES TO THE WARNING NOW TO
AVOID POTENTIAL VERIFICATION PENALTY. ALTHOUGH THE BACKING FLOW WL
ADVECT MORE UNMODIFIED COLD AIR INTO THE CWA...INCRSG WAD CLD IN
ADVANCE OF NEXT CLIPPER DISTURBANCE DIGGING SEWD TOWARD THE UPR LKS
WL TEND TO LIMIT THE DIURNAL TEMP FALL SOMEWHAT.

TUE...COLD FNT ASSOCIATED WITH THIS INCOMING CLIPPER SHRTWV/SFC LO
MOVING THRU NW ONTARIO IS PROGGED TO REACH THE WRN CWA BY 00Z WED.
PCPN IN ADVANCE OF THIS FNT WL BE LIMITED BY LLVL DRY AIR/ABSENCE OF
SGNFT MSTR INFLOW...BUT SUSPECT A PERIOD OF HEAVIER SHSN MIGHT
IMPACT THE W LATER IN THE DAY WITH SOME ENHANCEMENT OFF LK SUP IN
LLVL W FLOW WITH H85 TEMPS ARND -10C UNDER DPVA/DEEP LYR QVECTOR
CNVGC. NO MORE THAN CHC POPS WL BE APPROPRIATE OVER THE REST OF THE
CWA EXCEPT FOR THE E...WHERE SOME MOISTENING OF THE LLVLS IN SW FLOW
OFF LK MI WITH SUFFICIENTLY COLD AIR TO GENERATE LES MIGHT RESULT IN
SOME SHSN. GOING FCST DRY WX FOR THE FAR SCENTRAL SEEMS ON TRACK.

TUE NGT/WED...THE COLD FNT IS FCST TO SWING THRU THE UPR LKS AND
USHER IN A VERY CHILLY AIRMASS WITH H85 TEMPS AS LO AS -16C BY 12Z
WED. DESPITE THIS INCOMING CHILL...LES IN THE WAKE OF THE FROPA WL
BE STUNTED SOMEWHAT BY FAIRLY QUICK TRANSITION TO GENERAL ACYC FLOW
UNDER SHARP NVA/DEEP LYR QVECTOR DVGC/SUBSIDENCE THAT IS FCST TO
LOWER INVRN BASE OVER THE W TO BTWN 3-4K FT AGL BY 12Z WED. DESPITE
THESE NEGATIVES...OPTED TO GO WITH LIKELY POPS IN THE FAVORED NW
WIND SN BELTS...ESPECIALLY OVER THE E WITH LONGER FETCH AND SOME LK
NIPIGON PRE MOISTENING...GIVEN SUFFICIENT COLD AIR INFLUX/LK-H85
DELTA T APRCHG 20C. ON WED...THE LES IN THE NW WIND SN BELTS WL
DIMINISH WITH ARRIVAL OF SFC RDG AXIS/LOWERING INVRN BASE TO 2-3K FT
AGL/BACKING LLVL WINDS TOWARD THE W-SW.

EXTENDED...LONGER RANGE MODELS REMAIN VERY CONSISTENT SHOWING A
MAJOR PATTERN CHG LATER THIS COMING WEEK THAT WL FEATURE A ZONAL
FLOW OF UNSEASONABLY WARM PACIFIC AIR NEXT WEEKEND AS TROF IN ERN
CANADA LIFTS TO THE NE. ON THU...COLD CNDN HI PRES OVER ONTARIO
UNDER WNW FLOW ALF WL STILL BE DOMINATING THE UPR LKS...BUT
STRENGTHENING ISENTROPIC ASCENT ASSOCIATED WITH OVERRUNNING OF THE
RETREATING ARCTIC AIRMASS WL RESULT IN INCRSG CLDS TO THE NE OF WARM
FGEN IN THE NRN PLAINS TO LOWER LKS. AFTER THU...SOME VARIANCE
CREEPS INTO THE MODEL BLEND. RECENT ECMWF RUNS HAVE BEEN VERY
CONSISTENT INDICATING SOME -SN MAY DVLP ON THU NGT AND FRI AS THE
WARM FNT MOVES TO THE N. THE ECMWF INDICATES PCPN MAY EVEN
TRANSITION TO SOME -FZDZ AS DEEPER MSTR SHIFTS TO THE N AS LINGERING
NEAR SFC COLD AIR BECOMES SHALLOWER WITH LOWERING WARM FRONTAL INVRN
HGT. ON THE OTHER HAND...THE MAJORITY OF RECENT GFS RUNS SHOW THE
WARM FNT REMAINING FARTHER S AS A WAVE OF LO PRES ASSOCIATED WITH A
STRONGER SHRTWV RIPPLING THRU THE UPR MIDWEST RUNS W-E ALONG THIS
BNDRY. GIVEN THE LARGER SCALE TRENDS TOWARD RISING HGTS IN THE GRT
LKS AND CONSISTENCY OF THE ECMWF...WHICH IS ALSO PREFERRED BY
NCEP...TENDED TO USE THE ECMWF AS A GUIDE FOR PTYPE DURING THIS
TIME. BULK OF MODELS SHOW ANOTHER SHRTWV WL APRCH ON SAT. IF THE
ECMWF IS CORRECT...PCPN SHOULD BE MAINLY RA. ONLY MARITIME POLAR AIR
WL FOLLOW THIS DISTURBANCE FOR SUN UNDER THE ZONAL FLOW ALF...SO ANY
LES ON SUN SHOULD BE MINIMAL.
&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 655 PM EST SUN NOV 25 2012

ARRIVAL OF COLDER AIR WILL GENERATE MORE LAKE EFFECT -SHSN TONIGHT
THRU MON...MAINLY AT KIWD AND KCMX DUE TO WNW/NW FLOW. AT KCMX...
EXPECT A TREND TOWARD PREDOMINANTLY MVFR CONDITIONS THIS EVENING. AT
KIWD...ENHANCED LOW-LEVEL CONVERGENCE SHOULD LEAD TO A TREND TOWARD
PREDOMINANTLY IFR CONDITIONS THIS EVENING. AS ALWAYS WITH LAKE
EFFECT SHSN...CONDITIONS WILL BE QUITE VARIABLE. WOULD NOT BE
SURPRISED TO SEE CONDITIONS BRIEFLY AS LOW AS LIFR AND AS HIGH AS
VFR AT KIWD AND KCMX. AT KSAW...DOWNSLOPE NATURE OF WNW WINDS SHOULD
LEAD TO GENERALLY VFR CONDITIONS WITH FLURRIES/-SHSN AT TIMES.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 428 PM EST SUN NOV 25 2012

EXPECT NW WINDS TO 30 KTS TONIGHT AS LOW PRESSURE JUST NORTHEAST OF
LAKE SUPERIOR MOVES QUICKLY OFF TO THE EAST. THERE MAY ALSO BE A FEW
GALE GUSTS TO 35 KTS TONIGHT OVER NORTHERN AND EASTERN PORTIONS OF
LK SUPERIOR. WINDS WILL DIMINISH TO 15 TO 25 KT MONDAY AS HIGH
PRESSURE BUILDS INTO THE UPPER MS VALLEY AND THE WESTERN GREAT
LAKES.

AS HI PRES RIDGE MOVES THRU THE UPPER GREAT LAKES ON MON NIGHT...
EXPECT DIMINISHING WINDS BACKING TO THE SW. THIS SW WIND WILL
INCREASE UP TO 25 TO 30 KTS ON TUE AHEAD OF AN APPROACHING COLD
FRONT. FOLLOWING THE FRONTAL PASSAGE ON LATE TUE/TUE NIGHT...PLAN ON
A WIND SHIFT TO THE NW UP TO 30 KTS AS MUCH COLDER AIR MOVES OVER
LAKE SUPERIOR AND ENHANCES MIXING OF THE STRONGER WINDS TO THE
SURFACE. THE APPROACH OF ANOTHER HI PRES WILL BRING DIMINISHING
WINDS FOR WED. WITH RELATIVELY WEAK PRES GRADIENT IN PLACE THEN FOR
THU/FRI...WINDS SHOULD BE UNDER 25 KTS.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST MONDAY FOR MIZ006-085.

LAKE EFFECT SNOW ADVISORY UNTIL 5 AM EST TUESDAY FOR MIZ007.

LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST /9 AM CST/ MONDAY FOR
MIZ002-003-009-084.

LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

UPDATE...ROLFSON
SHORT TERM...JLB
LONG TERM...KC
AVIATION...ROLFSON
MARINE...JLB/KC

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

655 PM EST SUN NOV 25 2012

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 428 PM EST SUN NOV 25 2012

MAIN FCST CONCERNS ARE LES TRENDS.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 428 PM EST SUN NOV 25 2012

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 655 PM EST SUN NOV 25 2012

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 428 PM EST SUN NOV 25 2012

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST MONDAY FOR MIZ006-085.

LAKE EFFECT SNOW ADVISORY UNTIL 5 AM EST TUESDAY FOR MIZ007.

LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST /9 AM CST/ MONDAY FOR
MIZ002-003-009.

LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

SHORT TERM...JLB
LONG TERM...KC
AVIATION...ROLFSON
MARINE...JLB/KC

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

353 PM EST SAT NOV 24 2012

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 350 PM EST SAT NOV 24 2012

12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALF OVER
THE GRT LKS BTWN TROF OVER ERN NAMERICA AND A RDG OVER THE ROCKIES.
RIGHT NOW...THERE IS A SHRTWV RDG ALF DOMINATING THE UPR LKS...WITH
SFC HI PRES RDG AXIS STRETCHING FM NOW ONTARIO S INTO THE UPPER
MIDWEST. DESPITE THE APRCH OF THIS RDG AXIS AND LO INVRN BASE SHOWN
ON THE 12Z INL/MPX RAOBS THAT HAS ALLOWED AT LEAST PARTIAL CLEARING
OF LO CLDS OVER MN...THE SC OVER THE CWA HAS BEEN QUITE RESILIENT
WITH H925-85 THERMAL TROF /H85 TEMPS IN THE -12C TO -15C RANGE/
UNDER HIER INVRNS H85-5 AS SHOWN ON THE 12Z GRB/APX RAOBS IN THE
LLVL NW FLOW E OF THE INCOMING SFC HI PRES RDG. THESE LO CLDS ARE
TENDING TO BREAK UP MORE AGGRESSIVELY OVER THE FAR SCENTRAL CWA WITH
DOWNSLOPE NATURE OF THE LLVL FLOW. ALTHOUGH LOWERING SUBSIDENCE
INVRN HAS TENDED TO CAUSE THE LES IN THE CHILLY NW FLOW TO DIMINISH
WITH TIME...THE SHSN HAVE BEEN MOST PERSISTENT NEAR MUNISING WITH
UPSTREAM MOISTENING OFF LK NIPIGON AND MORE LLVL CNVGC ENHANCING THE
LES IN THAT AREA. LOOKING TO THE W...SKIES ARE PCLDY CLOSE TO THE
SFC RDG AXIS...BUT THICKER CLDS ASSOCIATED WITH WAD IN THE SSW FLOW
AHEAD OF ANOTHER SHRTWV NEAR LK WINNIPEG THAT HAS BEEN RIDING OVER
THE ROCKIES RDG ARE MOVING STEADILY TO THE E INTO ERN MN THIS AFTN.
SOME -SN HAS MOVED INTO NW MN THIS AFTN UNDER DEEP ISENTROPIC
ASCENT/SOME UPR DVGC IN THE EXIT REGION OF 120KT H3 JET MAX
SUPPORTING THE SHRTWV.

MAIN FCST CONCERNS THRU SUN INCLUDE TIMING OF SN AND PCPN AMOUNTS
TNGT IN ADVANCE OF CLIPPER TYPE SHRTWV NEAR LK WINNIPEG AND THEN
TRANSITION TO LES ON SUN IN ITS WAKE.

TNGT...AS SFC HI PRES RDG SHIFTS TO THE ERN GRT LKS...EXPECT SW
FLOW/ISENTROPIC ASCENT BTWN DEPARTING RDG AND SHRTWV NEAR LK
WINNIPEG TRACKING TO THE ESE ACRS ONTARIO TO DOMINATE. SINCE THE
MAIN PV ANOMALY WL BE PASSING TO THE N...SHARPER ISENTROPIC ASCENT
BEST SHOWN ON THE 280-290K SFCS /H8-65/ WL BE TRANSIENT AS WARM
CONVEYOR BELT MSTR AXIS SWINGS THRU THE UPR LKS AHEAD OF DRY
SLOTTING ON THE SRN FLANK OF PV ANOMALY TRACK. -SN SHOULD ARRIVE
OVER THE W IN THE EVNG AND PUSH TO ERY AFTER 06Z...WHEN THE PCPN WL
BEGIN TO DIMINISH W-E FOLLOWING THE SHIFT OF THE WARM CONVEYOR BELT
RIBBON TO THE E. PCPN CHCS WL BE ENHANCED BY RIBBON OF H85-7 FGEN...
SOME UPR DVGC IN LEFT EXIT REGION OF H3 JET MAX SUPPORTING THE
ONTARIO SHRTWV...AND SOME DPVA ASSOCIATED WITH ANOTHER SHRTWV
TRACKING THRU THE UPR MIDWEST ON THE SRN FLANK OF THE MAIN PV
ANOMALY. GIVEN FCST H7 SPECIFIC HUMIDITY UP TO 2 G/KG AND A 3-6 HR
PERIOD OF -SN WITH TRANSIENT WARM CONVEYOR BELT/DEEP ASCENT...LOOKS
LIKE 1 TO 2 INCHES OF SN IS LIKELY WITH DECENT OMEGA IN THE DGZ. 12Z
GUIDANCE SHOWS THE SHARPER ISENTROPIC ASCENT/FGEN IMPACTING THE WI
BORDER AREA WITH HIER QPF/SN AMOUNTS ARND 2 INCHES MOST LIKELY
THERE. SOME OF THE MODELS ALSO HINT THERE COULD BE SOME LK
ENHANCEMENT OFF LK MI...BUT THE H925 WINDS LOOK TO BACK TO A MORE
FAVORABLE SW DIRECTION ONLY BRIEFLY TO ALLOW FOR TOO MUCH
ENHANCEMENT AT ISQ-ERY. WITH RELATIVELY QUICK ARRIVAL OF THICKER
CLDS/WAD THIS EVNG...EXPECT NEAR STEADY TEMPS MUCH OF THE NGT AFTER
EARLY MODEST DIURNAL TEMP FALL.

SUN...LINGERING -SN OVER THE E WL END SOON AFTER 12Z FOLLOWING EXIT
OF WARM CONVEYOR BELT MSTR RIBBON TO THE E AND ARRIVAL OF DRY
SLOTTING. HOWEVER...12Z MODELS HAVE TENDED TO DIG THE PV ANOMALY
MORE TO THE ESE OVER NE LK SUP DURING THE DAY. SO AS THE DAY GOES
ON...A COLD CYC NW FLOW WL DVLP IN THE WAKE OF COLD FROPA AS
ASSOCIATED SFC LO SHIFTS TO JUST E OF LK SUP BY 00Z MON. AT THE SAME
TIME...AN AXIS OF SHARPER QVECTOR CNVGC/DPVA AND SOME DEEPER MSTR WL
IMPACT MAINLY THE NE HALF OF THE FA CLOSER TO THE TRACK OF THE
SHRTWV. WITH H85 TEMPS PROGGED TO FALL AS LO AS -15C OVER THE W HALF
OF LK SUP IN THE AFTN...EXPECT MORE WDSPRD LES TO DEVELOP IN THAT
AREA. ALSO BUMPED UP POPS OVER THE NE IN THE AFTN ESPECIALLY NEAR LK
SUP GIVEN FAVORABLE ALIGNMENT OF ONSHORE WNW FLOW...DEEPER MSTR/
DPVA/QVECTOR CNVGC...AND COOLING. THE DAY SHOULD BE DRY OVER THE
SCENTRAL WITH DOWNSLOPE FLOW IN THE ABSENCE OF ANY DYNAMIC
SUPPORT/DEEP MSTR THERE.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 350 PM EST SAT NOV 24 2012

THE MAIN FOCUS IN THE LONG TERM REVOLVES AROUND THE CHANCE FOR
MODERATE LAKE EFFECT SNOW ACCUMULATION EAST NEAR LAKE SUPERIOR
LATE SUNDAY NIGHT THROUGH MONDAY. EXACT LOCATIONS OF THIS POTENTIAL
ARE STILL UNCERTAIN...THOUGH THE MAIN THREAT APPEARS TO BE IN ALGER
COUNTY FROM MUNISING TO GRAND MARAIS AND SOUTH INTO NORTHERN
SCHOOLCRAFT COUNTY. ANOTHER ROUND OF LIGHT SNOW VERY SIMILAR TO
TONIGHTS SYSTEM WILL MOVE THROUGH THE AREA TUESDAY NIGHT. MILDER
PATTERN CHANGES WILL THEN BE IN THE MAKING TOWARD THE END OF THE
WEEK.

SUNDAY NIGHT THROUGH MONDAY NIGHT...THE SHORTWAVE TROUGH ASSOCIATED
WITH THE CLIPPER SYSTEM NOTED IN THE SHORT TERM WILL BE CROSSING
NORTH-CENTRAL LAKE SUPERIOR AND WESTERN UPPER MI AT THE START OF THE
PERIOD. THE ECMWF AND REGIONAL GEM HAVE BEEN QUICKER WITH THE
SHORTWAVE WITH EACH PROGRESSIVE RUN...AND HAVE COME IN LINE WITH THE
GFS AND NAM SOLUTIONS. TRENDS FROM BOTH THE GFS AND ECMWF ARE TO ADD
SUBTLE AMPLIFICATION TO THE WNW FLOW IN THE MID-LEVELS OVER THE
GREAT LAKES...WHILE THE REGIONAL GEM HAS TRENDED TO A LESS AMPLIFIED
FLOW. PREFER THE IDEA PRESENTED BY THE GFS/ECMWF AS THE NICE SHOT OF
CAA BEHIND THE LOW-LEVEL CLIPPER WILL LIKELY ADD SOME AMPLIFICATION
TO THE MID-LEVEL TROUGHING.

LINGERING LIGHT SNOW FROM THE CLIPPER WILL BE ENDING ACROSS THE
EASTERN PORTION OF THE CWA AT 00Z MONDAY AS THE LOW DEPARTS INTO SE
ONTARIO. CAA IMMEDIATELY BEHIND THE SYSTEM IS NOT ALL THAT
IMPRESSIVE...WITH H8 TEMPS ONLY AROUND -10C OVER EASTERN LAKE
SUPERIOR AT 06Z MONDAY. HOWEVER...H8 TEMPS BEGIN TO FALL FOR THE
WESTERN HALF...REACHING -14C BY 06Z MONDAY. AT THE SAME TIME...A
WEAK RIDGE BETWEEN THE DEPARTING TROUGH AND INCOMING AMPLIFYING
TROUGH WILL BE PASSING OVERHEAD AND LIKELY DISRUPT THE LOW-LEVEL
SURFACE FLOW. WHAT MAKES THIS CONCERNING IS THAT SFC TO H8 FLOW FROM
THE NW WOULD PUT A DOMINANT LES BAND INTO FAR EASTERN ALGER COUNTY
BEGINNING SUNDAY EVENING...WHILE A BACKING OF THE FLOW BEHIND THE
SUBTLE RIDGE WOULD TEMPORARILY PUSH THE BAND ALONG THE SHORE. STILL
BEING TWO DAYS OUT...THE CONNECTION BETWEEN THE MID-LEVEL FLOW AND
SFC LES SET-UP IS SOMEWHAT UNCLEAR...BUT WOULD NOT BE SURPRISED IF
THE BAND WOBBLES BETWEEN EASTERN ALGER COUNTY AND NORTHERN LUCE
COUNTY ON EARLY MONDAY MORNING. THEN...THE SECONDARY TROUGH WILL AID
LES INTENSITY ACROSS THE WHOLE NORTH SHORE OF UPPER MI LATER MONDAY
MORNING INTO THE AFTERNOON. THIS WILL OCCUR AS THE BEST CAA AND
COLDEST H8 TEMPS...AROUND -15 TO -16C...WILL BE MOVING OVER THE
LAKE. ADDITIONALLY...LAKE-INDUCED EQUILIBRIUM VALUES BASED OFF OF A
CONSERVATIVE LAKE WATER TEMPERATURE OF 5C WILL BE UPWARDS OF 7KFT
ACROSS THE WEST AND 9KFT FOR THE EAST. FINALLY...THE DGZ WILL BE
LOCATED IN THE HIGHEST 3KFT OF THE CONVECTIVE LAYER IN THE
EAST...LEADING TO THE POTENTIAL FOR INCREASED AGGREGATION FROM
DENDRITES AND THUS HIGHER SNOW RATIOS OF ABOUT 20 TO 1.
THEREFORE...EXPECT THE HIGHEST LES INTENSITY MONDAY MORNING INTO
EARLY AFTERNOON OVER THE EAST NEAR LAKE SUPERIOR.

THE NAM...GEM...AND LOCAL WRF ALL HAVE A DOMINANT BAND WITH
SIGNIFICANT LES FOR CENTRAL ALGER AND NORTHERN SCHOOLCRAFT COUNTY. A
BLEND OF NAM AND LOCAL WRF QPF RESULTED IN ACCUMULATIONS OF 6-10
INCHES CENTERED OVER MELSTRAND. ONLY USED THIS BLEND TO SEE
POTENTIAL AND WILL USE A MORE CONSERVATIVE APPROACH GIVEN THE
UNCERTAINTY OF BAND PLACEMENT. NEEDLESS TO SAY...HEADLINES MAY BE
NEEDED IF HI-RES MODELS REMAIN CONSISTENT WITH LES BAND PLACEMENT.

DRY AIR ADVECTION FROM THE SOUTHWEST IN THE LOW LEVELS...AND H8 WAA
OVERNIGHT MONDAY WILL BEGIN TO ERODE LES FROM WEST TO EAST ACROSS
THE CWA. INVERSION HEIGHTS WILL ALSO CRASH FROM AROUND 9KFT 00Z
TUESDAY TO <5KFT BY 09Z TUESDAY. MEANWHILE WINDS WILL BEGIN BACKING
AND SHOULD PUSH REMAINING LES OFFSHORE...WITH LITTLE ACTIVITY
REMAINING BY TUESDAY MORNING.

TUESDAY THROUGH WEDNESDAY...ANOTHER SHORTWAVE TROUGH DIGGING ESE OUT
OF CANADA WILL IMPACT THE CWA BY TUESDAY AFTERNOON AND BRING A ROUND
OF LIGHT SNOW TO MAINLY THE NORTHERN CWA. THE BEST UPPER LEVEL PV
ANOMALY AND MID-LEVEL Q-VECTOR DIVERGENCE ARE PROGGED TO MOVE
THROUGH TUESDAY AFTERNOON AND EVENING. THE LEFT EXIT OF A 120KT NW
TO SE ORIENTED UPPER JET WILL BE TRACKING ACROSS CENTRAL WI...SO
BEST FEATURES DO NOT QUITE LINE UP. THE LOWEST LEVELS WILL BE DRY
ENOUGH TO THE SOUTH TO PREVENT INITIAL PRECIP FROM REACHING THE
GROUND. DID NOT MAKE MANY CHANGES TO THE PREVIOUS FORECAST OTHER
THAN INCREASE POPS SLIGHTLY FOR THE ENTIRE CWA. THE TROUGH AXIS WILL
THEN PASS THROUGH THE CWA BY 12Z WEDNESDAY AND USHER IN
ANOTHER...YET SHORT-LIVED AND WEAKER...LES EVENT. INVERSION HEIGHTS
COLLAPSE QUITE QUICKLY TO ABOUT 4KFT BY WEDNESDAY AFTERNOON...AND
THE AIR BEHIND THIS SYSTEM IS CONSIDERABLY DRY THROUGHOUT THE
COLUMN. THEREFORE...EXPECTATION IS THAT THERE WILL BE A QUICK LES
EVENT WEDNESDAY MORNING INTO EARLY AFTERNOON FOR THE NW
SNOWBELTS...MAINLY ACROSS THE KEWEENAW PENINSULA AND EAST OF
MUNISING WHERE MOISTURE IS MORE ABUNDANT.

WEDNESDAY NIGHT THROUGH SATURDAY...THE PATTERN TURNS QUIET FOR MUCH
OF THE UPPER GREAT LAKES FOR THE SECOND HALF OF THE WEEK. OTHER THAN
SOME LIGHT LES POSSIBLE EAST NEAR LAKE SUPERIOR ON THURSDAY
NIGHT...NO REAL SIGNIFICANT PRECIP CHANCES PRESENT THEMSELVES AS THE
MAIN ENERGY REMAINS SOUTH OF THE CWA WITH AN UPPER LEVEL DISTURBANCE
MOVING ACROSS THE MID MISSISSIPPI VALLEY ON FRIDAY. THOUGH ON THE
EDGE OF THE FORECAST PERIOD...A STRONG RIDGE WITHIN PACIFIC FLOW
LOOKS TO BRING WELL-ABOVE AVERAGE TEMPS TO BEGIN DECEMBER.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 350 PM EST SAT NOV 24 2012

EXPECT MVFR CIGS AT ALL 3 SITES TO GIVE WAY TO VFR CONDITIONS BY
THIS EVNG WITH THE ARRIVAL OF A SFC HI PRES RDG AXIS. SOME -SN IN
ADVANCE OF THE NEXT CLIPPER TYPE LO PRES SYSTEM WL THEN ARRIVE W-E
LATER THIS EVNG...LIKELY DROPPING VSBYS TO IFR RANGE DURING THE
EXPECTED 3-6HR PERIOD OF -SN. AFTER THE -SN ENDS W-E...EXPECT
LINGERING MVFR CIGS WITH RESIDUAL LLVL MSTR. THE ARRIVAL OF COLDER
AIR WL GENERATE MORE LK EFFECT -SHSN ON SUN MRNG...ESPECIALLY AT IWD
AND ESPECIALLY CMX WHERE THE FCST W WIND WL UPSLOPE. ON THE OTHER
HAND...CONDITIONS ARE LIKELY TO TREND TO VFR ON SUN AT SAW WITH
DOWNSLOPE WIND COMPONENT.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 350 PM EST SAT NOV 24 2012

EXPECT S-SW WINDS UP TO 20 KTS IN ADVANCE OF A CLIPPER SYSTEM
TONIGHT TO VEER TO THE WNW ON SUN AS THE LO MOVES TO THE E OF LAKE
SUP AND DRAGS A COLD FRONT ACROSS THE AREA.

NORTHWEST WINDS OF 20 TO 30 KNOTS DUE TO HIGH PRESSURE QUICKLY
IMPINGING ON A DEPARTING LOW OVER FAR EASTERN UPPER MICHIGAN WILL BE
POSSIBLE SUNDAY NIGHT...WITH EVEN A FEW GALE FORCE GUSTS UP TO 35
KNOTS NOT OUT OF THE QUESTION. EXPECT THESE WINDS TO QUICKLY
DECREASE ON MONDAY AS A HIGH PRESSURE RIDGE SETTLES OVER THE UPPER
GREAT LAKES. SOUTHWEST WINDS OF 20 TO 25 KNOTS WILL THEN BE
POSSIBLE...MAINLY FOR THE WEST HALF OF LAKE SUPERIOR ON TUESDAY
AHEAD OF A COLD FRONT. ONCE THE FRONT PASSES TUESDAY AFTERNOON AND
EVENING...WINDS WILL VEER TO THE W/NW AND INCREASE TO 20 TO 25 KNOTS
FOR THE EAST HALF OF THE LAKE THROUGH WEDNESDAY. EXPECT WINDS TO
REMAIN BELOW 20 KNOTS FOR THE REMAINDER OF THE PERIOD.

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

SHORT TERM...KC
LONG TERM...KLUBER
AVIATION...KC
MARINE...KC/KLUBER

AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

309 PM CST SAT NOV 24 2012

.DISCUSSION...

A SHORT WAVE AND CLIPPER LIKE LOW PRESSURE SYSTEM OVER EASTERN ND
AT MID AFTERNOON WILL MOVE SOUTHEAST ACROSS THE MN/WI TONIGHT.
THERE IS A DECENT PV ANOMALY AS WELL THAT WILL PASS BETWEEN THE
TWIN CITIES AND DULUTH THIS EVENING. THIS SITUATION IS SOMEWHAT
SIMILAR TO THAT OF THURSDAY EVENING...EXCEPT THE SYSTEM TONIGHT IS
A LITTLE WEAKER AND THE ORIENTATION IS NW TO SE. PLENTY OF FORCING
AND DEEP LAYER SATURATION IS SEEN BY THE VARIOUS MODEL SOLUTIONS
PASSING ACROSS EAST CENTRAL MN AND WEST CENTRAL WI THIS EVENING.
EVEN THE SOUTHERN EDGE OF THE THALER QG INSTANTANEOUS PRECIPITATION
RATE NICKS THE TWIN CITIES THIS EVENING. HOWEVER...MUCH LIKE
THURSDAYS SNOW EVENT...THE MODEL SOLUTIONS ARE VERY DRY FOR MUCH
OF OUR CWA. THE EXCEPTION IS NEAR RUSK COUNTY WHERE A FEW
HUNDREDTHS OF AN INCH ARE SEEN.

THIS SEEMS UNREALISTIC WITH THE DEEP SATURATION SEEN COMBINED WITH
THE OMEGA AND SNOW GROWTH ALMOST COLLOCATED. GRANTED IT ONLY LASTS
FOR A FEW HOURS. RECENT RADAR TRENDS SHOWING SOME BANDING ACROSS
EASTERN ND AND NW MN WITH MID LEVEL FRONTOGENESIS EVIDENT IN THE
RAP JUST TO THE WEST. THEREFORE...USED LIKELY POPS THIS EVENING
ALONG AND EAST OF A LINE FROM MILLE LACS TO EAU CLAIRE WITH AROUND
AN INCH OF SNOW ACCUMULATION. CHANCE POPS FOR LITTLE FALLS..ST
CLOUD...THE TWIN CITIES AND RED WING WITH ACCUMULATIONS LESS THAN
AN INCH. KEPT CHANCE POPS IN PLACE OVER THE LADYSMITH AND AUGUSTA
AREAS FOR THE OVERNIGHT HOURS.

ANOTHER COLD DAY ON SUNDAY ALONG WITH BRISK NORTHWEST WINDS IN THE
WAKE OF THE LOW AND COLD FRONT. HIGHS FROM THE LOWER 20S TO LOWER 30S
FROM NORTH TO SOUTH. SKY COVER IS A LITTLE PROBLEMATIC ON SUNDAY.
THE MORNING MAY BEGIN WITH SOME SUNSHINE BUT EXTENSIVE LOW
CLOUDINESS MAY PUSH SOUTHWARD ACROSS THE FA DURING THE AFTERNOON
AND NIGHT. CONFIDENCE IS NOT HIGH AND THIS COULD AFFECT THE
OVERNIGHT LOW FOR SUNDAY NIGHT. AT THIS TIME...MONDAY SHOULD BE THE
COLDEST DAY IN THE FORECAST PERIOD AS THE LOW LEVEL COLD TROUGH
MOVES BY. HIGHS ARE ONLY FORECAST IN THE TEENS TO LOWER 20S.

THE LONGER RANGE PORTION OF THE FORECAST THROUGH NEXT SATURDAY
LOOKS DRY ALONG WITH A SLOW WARMING TREND. SOME PRECIPITATION IS
LIKELY WELL NORTH OF OUR AREA ON TUESDAY AND PERHAPS AGAIN ON
FRIDAY. BOTH THE EC AND GFS HAVE A LOW PRESSURE STORM SYSTEM
DEVELOPING OVER THE CENTRAL AND NORTHERN PLAINS NEXT WEEKEND. THIS
COULD BRING ANOTHER SURGE OF VERY MILD AIR INTO THE AREA FOR
SUNDAY AND MONDAY. 850MB TEMPS ARE PROGGED INTO THE 8-12 DEG C
RANGE. SOME EXTENDED GUIDANCE HIGHS ARE ALREADY NEAR 50 FOR THE
TWIN CITIES NEXT SATURDAY. THE NORMAL HIGH IS 32.

.AVIATION... /18Z TAF ISSUANCE/

MAIN AVIATION CONCERN IS ONSET OF -SN THIS EVENING...AND HOW LOW
THE VSBYS/CIGS COULD GET DEPENDING UPON THE STRENGTH OF THE SHRTWV
MOVING ACROSS THE FA LATE THIS AFTN/EVENING.

PREVIOUS TAFS HAD -SNSH FOR MOST AREAS EXCEPT RWF... WHICH SEEMS
REASONABLE DUE TO UPSTREAM OBS AND THE STRENGTH OF THE SHRTWV.
LATEST RAP HAS A FAIRLY STRONG WAA PATTERN DEVELOPING BY 21Z-00Z
WHICH WOULD BE THE START OF SATURATION FROM THE TOP...DOWN. AFT
00Z...AS THE CONCENTRATION THE FAVORED DENDRITIC ZONE AND AMPLE
LIFT DEVELOPS...COULD SEE VSBYS DROP TO 1-2SM IN THE NE FA IN SNOW.
MAINLY AFFECTING RNH/EAU. ELSEWHERE...THE FAST NATURE OF THIS WAVE
AND LIMITED TIME TO SATURATE THE LOWER LAYERS OF THE
ATMOSPHERE...WILL ONLY HAVE -SN...WITH NO RESTRICTIONS TO VSBY.
WINDS WILL START FROM THE SOUTH...BECOME MORE SW THIS
EVENING...THEN SHIFT TO THE NW AND INCREASE OVERNIGHT...AND SUNDAY
MORNING. A FEW GUSTS OVER 20 KTS ARE POSSIBLE BY 18Z. ANOTHER
CONCERN IS WHETHER WE GET MVFR/IFR CIGS BEHIND THE FRONT LATE
TONIGHT/SUNDAY MORNING. UPSTREAM OBS IN SOUTH CENTRAL CANADA HAVE
BEEN IN THE IFR/MVFR RANGE THIS MORNING...AND THIS WOULD BE THE
SOURCE REGION AS THIS AIR MASS MOVES SE OVERNIGHT. HAVE DECIDED TO
ONLY INTRODUCE SCT012...BUT LATER SHIFTS WILL NEED TO UPDATE AS
NECESSARY.

KMSP...

AS PREVIOUSLY STATED...FAST SHRTWV ACROSS SOUTH CENTRAL CANADA WILL
PROVIDE INCREASING CLOUDINESS THIS AFTN/EVENING...WITH CLDS
LOWERING TO LOW END VFR BY 00-03Z. HAVE KEPT VSBY UNRESTRICTED AS
THE MAIN -SN SHOULD BE FURTHER TO THE E/NE OF MSP AIRFIELD...BUT
LATER SHIFTS MAY CONSIDER LOWERING THESE VSBY TO MVFR IF THE
SHRTWV IS STRONGER. WINDS WILL START FROM THE SSE...BECOME MORE
SSW THIS EVENING...THEN SHIFT TO THE NW BY MORNING...WITH GUSTS
LIKELY AFT 15-18Z. STILL NOT CONFIDENT ON MVFR CIGS BY SUNDAY
AFTN...BUT SOMETHING TO CONSIDER DUE TO THE DEPTH OF THE MOISTURE
BLW 3K IN THE LATEST MODEL RUN.

/OUTLOOK FOR KMSP/

SUN/MON...MVFR CIGS POSSIBLE WITH -SNSH. WINDS WNW AT 10G20KTS.
TUE...VFR. WINDS SSW AT 10 TO 15 KTS.
WED...VFR. WINDS NE/E AT 5 TO 10 KTS.

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

RAH/JLT

AREA FORECAST DISCUSSION...UPDATED

NWS DULUTH MN

1138 AM CST SAT NOV 24 2012

.AVIATION.../18Z TAF ISSUANCE/

A RIDGE OF HIGH PRESSURE IS OFFERING A SHORT WINDOW OF VFR
CONDITIONS ACROSS NE MINNESOTA AND NW WISCONSIN EARLY THIS
AFTERNOON...EXCEPT AT KHYR WHERE THERE IS LINGERING MVFR CIGS. THE
S WINDS WILL INCREASE THIS AFTERNOON AHEAD OF AN APPROACHING LOW
PRESSURE SYSTEM. CLOUDS ARE EXPECTED TO INCREASE AND CIGS LOWER FROM
WEST TO EAST THROUGH THIS AFTERNOON AND INTO THIS EVENING IN
ADVANCE OF THE APPROACHING COLD FRONT ASSOCIATED WITH SYSTEM.
THERE WILL BE PERIODS OF IFR/MVFR CONDITIONS THROUGH TONIGHT DUE
TO CIGS AND REDUCED VIS FROM THE COMBINATION OF WIND AND -SN.
THE WINDS WILL BECOME NW LATE THIS EVENING AND OVERNIGHT. THE -SN
WILL DIMINISH OR MOVE OFF TO THE EAST LATE TONIGHT AND TOMORROW
MORNING. THERE SHOULD BE LINGERING MVFR CIGS TOMORROW
MORNING.

PREV DISCUSSION... /ISSUED 402 AM CST SAT NOV 24 2012/

SHORT TERM...TODAY THROUGH SUNDAY.

AT 330 AM...A VARIETY OF CONDITIONS WERE FOUND ACROSS THE
NORTHLAND. THERE WAS A LARGE AREA OF LOW CLOUDS ACROSS NW WI WITH
SOME SNOW SHOWERS. A CHECK OF WEBCAMS IN THE HURLEY AREA INDICATED
LITTLE SNOW ACTIVITY BUT LIKELY SOME SNOW SHOWERS OR FLURRIES.
THERE WAS ANOTHER AREA OF LOW CLOUDS ACROSS WESTERN AREAS OF THE
CWA WITH SOME SNOW SHOWERS AND FLURRIES AS WELL. CLEAR SKIES WERE
FOUND IN A NW TO SE AREA IN BETWEEN. TEMPERATURES RANGED FROM THE
TEENS IN CLOUDY AREAS TO THE SINGLE DIGITS ABOVE AND BELOW ZERO IN
THE CLEAR AREAS.

A STRENGTHENING SHORTWAVE AND SURFACE LOW PRESSURE SYSTEM NOW
MOVING INTO SASKATCHEWAN AND MONTANA WILL AFFECT THE WEATHER
ACROSS THE REGION STARTING THIS AFTERNOON AND CONTINUING INTO
SUNDAY. SKIES WILL BE PARTLY SUNNY FOR MOST AREAS THIS
MORNING...BUT CLOUDS WILL QUICKLY INCREASE FROM THE WEST DURING
THE DAY. A COMBINATION OF FAVORABLE JET DYNAMICS...Q-VECTOR
CONVERGENCE AND FGEN WILL PRODUCE AN INCREASE IN SNOW STARTING
THIS AFTERNOON AND CONTINUING INTO TONIGHT. THE HRRR AND 4KM WRF
SEEM TO HAVE A GOOD HANDLE ON THE EVOLUTION OF THIS SYSTEM. WILL
INCREASE POPS CONSIDERABLY ACROSS THE BOARD...WITH CATEGORICAL
POPS ACROSS THE NORTH AND LIKELY FOR MOST AREAS LATER TODAY AND
THIS EVENING. CURRENT THINKING IS THAT THERE WILL BE WIDESPREAD 1
TO 3 INCH AMOUNTS...WITH 2 TO 4 INCHES ACROSS MUCH OF NORTHERN MN.
COULD ALSO BE SOME HIGHER AMOUNTS ACROSS THE NORTH SHORE OF LAKE
SUPERIOR...AS SOUTHWEST WINDS LEND SOME OROGRAPHIC LIFT ALONG THE
NORTH SHORE. MAY NEED TO RAISE AMOUNTS THERE IN LATER FORECASTS.
DRIER AIR WILL MOVE IN BEHIND THE SYSTEM TONIGHT AND INTO
SUNDAY...WITH GUSTY WEST TO NORTHWEST WINDS BECOMING THE MAIN
STORY FOR THE NORTHLAND ON SUNDAY. COULD STILL BE SOME LINGERING
SNOW SHOWERS...ESPECIALLY ACROSS THE NORTH...AND LAKE EFFECT SNOW
SHOWERS SHOULD DEVELOP FOR THE SOUTH SHORE.

LONG TERM...SUNDAY NIGHT THROUGH SATURDAY.
NW FLOW WILL BRING A CONTINUED CAA REGIME THROUGH THE WEEKEND.
MODELS ARE IN GOOD AGREEMENT THAT H85 TEMPS FALL INTO THE NEGATIVE
UPPER TEENS TO AROUND NEGATIVE 20 C EARLY MONDAY MORNING. HAVE
LOWERED TEMPS SUNDAY NIGHT AND MONDAY TO ACCOUNT FOR THIS COLD AIR.
THE NW TRAJECTORIES AND COLD H85 TEMPS WILL BRING AN OPPORTUNITY FOR
LK EFFECT SNOW ALONG THE SOUTH SHORE OF LK SUPERIOR SUNDAY NIGHT
INTO MONDAY WHERE LIGHT SNOW ACCUMULATION WILL BE POSSIBLE ALONG THE
GOGEBIC RANGE. LATEST NAM BUFR SOUNDINGS SHOW THE STEEP LAPSE RATES
ASSOCIATED WITH THE COLD AIR...AND A SHALLOW LAYER OF
MOISTURE...REMAINS OVER THE ARROWHEAD ZONES THROUGH SUNDAY NIGHT
WHERE FLURRIES OR VERY LIGHT SHSN MAY LINGER.

LONG TERM MODELS CONTINUE TO SHOW ANOTHER SHORT WAVE DROPS OUT OF
CANADA AND SWEEPS OVER THE NORTHLAND MID-WEEK. HAVE KEPT SMALL POPS
IN THE NRN ZONES TUESDAY.

.POINT TEMPS/POPS...
DLH 19 24 8 19 / 70 10 10 10
INL 15 19 6 17 / 70 10 10 10
BRD 19 25 6 17 / 30 10 10 0
HYR 20 28 10 20 / 60 10 10 0
ASX 22 30 15 22 / 70 10 20 10

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 4 AM CST SUNDAY
FOR LSZ140.

SHORT TERM...BERDES
LONG TERM....GROCHOCINSKI
AVIATION...GROCHOCINSKI

AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

1124 AM CST SAT NOV 24 2012

.DISCUSSION...
OVERALL IT LOOKS TO BE A QUIET UPCOMING WEEK... ALTHOUGH THERE ARE
A FEW ITEMS OF CONCERN. THE MAIN ISSUES PRESENT THEMSELVES OVER
THE FIRST 36-48 HOURS OF THE FORECAST AS WE SEE ANOTHER CHANCE FOR
SOME LIGHT SNOW ACROSS A PORTION OF THE AREA... FOLLOWED BY A
REINFORCING BLAST OF COLD AIR. IN THE BIG PICTURE... THE RIDGE OUT
WEST WILL REMAIN IN PLACE FOR THE EARLY PART OF THE WEEK AS UPPER
ENERGY CURRENTLY CRESTING IT WORKS THROUGH OUR AREA AND HELPS
MAINTAIN THE EASTERN TROUGH. HOWEVER... BY THE END OF THE WEEK THE
ECMWF AND GFS BOTH SUGGEST THE PATTERN WILL BECOME MORE ZONAL AS A
TROUGH STARTS TO SETUP OFF THE WEST COAST. INDICATIONS ARE THAT
THIS WILL EVENTUALLY LEAD TO A DECENT RIDGE OVER THE
CENTER/EASTERN PART OF THE COUNTRY TOWARD THE END OF NEXT WEEKEND
INTO THE FOLLOWING WEEK... BUT FOR NOW WE NEED NOT WORRY ABOUT
THAT AND WILL GENERALLY BE DEALING WITH BELOW NORMAL TEMPERATURES
AND DRY WEATHER.

INCREASING RETURN FLOW AND WARM ADVECTION TODAY WILL BRING
INCREASING MID-HIGH CLOUDS THROUGH THE DAY. SHORTWAVE CURRENTLY
WORKING THROUGH THE CANADIAN ROCKIES WILL DROP EAST-SOUTHEAST
LATER TODAY AND THIS EVENING AND HELP DRIVE A SURFACE LOW BY TO
OUR NORTH WHILE IT PUSHES A SURFACE TROUGH ACROSS OUR AREA. THE
BEST UPPER LEVEL DIVERGENCE AND COMBINATION OF ISENTROPIC
LIFT/SATURATION WILL STAY TO OUR NORTH... BUT WE SHOULD MANAGE TO
SEE SOME SOUTHWARD EXTENSION OF PCPN ALONG/AHEAD OF THE TROUGH
AXIS FROM LATE THIS AFTERNOON INTO TONIGHT. KEPT SOME CHANCE POPS
GOING FOR THE NORTHERN PART OF THE CWFA... AND BRACKETED THEM WITH
FLURRIES TO THE SOUTH. REMOVED THE MENTION OF FREEZING PCPN SINCE
IT APPEARS THAT ANY ELEVATED WARM LAYER WILL STAY JUST SOUTH OF
THE AREA OF PCPN. IF PCPN GETS FARTHER SOUTH THE FORECAST
SOUNDINGS FROM THE NAM AND GFS WOULD SUGGEST THAT THE ELEVATED
ABOVE 0C WARM LAYER SHOULD COOL TO THE WET BULB AND WOULD DROP
BELOW FREEZING WITH ANY PCPN. OBVIOUSLY IF THE RETURN FLOW IS
STRONG THAN EXPECTED AND THE WARM NOSE GETS FARTHER NORTH THEN
THERE COULD BE AN ISSUE WITH SOME LIGHT FZRA OR SLEET ON THE
SOUTHERN END OF THE PCPN AREA... BUT FOR NOW IT LOOKS LIKE WE
SHOULD AVOID THAT SCENARIO.

THE MAIN COLD FRONTAL BOUNDARY WILL DROP SOUTH THROUGH THE AREA
SUNDAY AFTERNOON AND EVENING... WITH A BLAST OF COLD AIR ARRIVING
FOR MONDAY. A FEW FLURRIES COULD BE SEEN IN THE WAKE OF THE
FRONT... BUT FOR NOW IT LOOKS LIKE THOSE SHOULD STAY TO OUR
NORTH/NORTHEAST AS ANTICYCLONIC BOUNDARY LAYER FLOW QUICKLY WORKS
INTO OUR AREA. WINDS WILL STAY UP SOME THROUGH THE NIGHT SUNDAY
NIGHT... WHICH WILL COMBINE WITH FALLING TEMPERATURES TO CREATE
SOME BELOW ZERO WIND CHILLS ACROSS A GOOD PART OF THE AREA.
MONDAY/S HIGHS WILL ONLY BE IN THE TEENS OVER THE NORTHWEST AND
NORTH CENTRAL PORTION OF THE AREA... WITH MOST OTHER LOCATIONS
BARELY ECLIPSING 20. IF CLOUD COVER STICKS AROUND MORE THAN
EXPECTED THEN 20 COULD EVEN BE A STRETCH. THE REMAINDER OF THE
WEEK WILL SEE PROGRESSIVELY WARMER TEMPERATURES... WITH READINGS
NEAR OR PERHAPS A BIT ABOVE NORMAL BY THE END OF THE WEEK AS
NORTHWEST UPPER FLOW BECOMES WESTERLY. THERE MAY EVENTUALLY BE A
NEED TO INCLUDE SOME CHANCE OF PCPN FOR FRIDAY WITH BOTH THE ECMWF
AND GFS SUGGESTING A SURFACE WAVE TO OUR SOUTH AND THE MAIN
BAROCLINIC ZONE LOITERING NEARBY. HOWEVER... WITH VIRTUALLY NO
RETURN FLOW INTO THE REGION THROUGH THE WEEK... IT IS TOO EARLY TO
HAVE MUCH FAITH IN ANY PCPN BEING GENERATED AT THIS POINT.

.AVIATION.../18Z TAF ISSUANCE/

MAIN AVIATION CONCERN IS ONSET OF -SN THIS EVENING...AND HOW LOW
THE VSBYS/CIGS COULD GET DEPENDING UPON THE STRENGTH OF THE SHRTWV
MOVING ACROSS THE FA LATE THIS AFTN/EVENING.

KMSP...

/OUTLOOK FOR KMSP/

SUN/MON...MVFR CIGS POSSIBLE WITH -SNSH. WINDS WNW AT 10G20KTS.
TUE...VFR. WINDS SSW AT 10 TO 15 KTS.
WED...VFR. WINDS NE/E AT 5 TO 10 KTS. ..JLT..

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

TRH/JLT

AREA FORECAST DISCUSSION

NWS DULUTH MN

637 AM CST SAT NOV 24 2012

.AVIATION.../12Z TAF ISSUANCE/
COLD NWLY FLOW WILL RESULT IN OCCASIONAL -SHSN AND IFR/MVFR
CIGS....MAINLY AROUND KBRD AND KHYR THIS MORNING. A RIDGE OF HIGH
PRESSURE WILL ALLOW FOR A BRIEF PERIOD OF CLEARING AS IT
TRANSLATES ACROSS THE REGION TODAY. HOWEVER...THE NEXT LOW
PRESSURE SYSTEM WILL QUICKLY DROP OUT OF CANADA AND INTO NORTHWEST
MINNESOTA THIS AFTERNOON. THE LOW WILL SPREAD SNOW SHOWERS WITH LOWERING
CEILINGS/VSBYS ACROSS THE FORECAST AREA THROUGH THE LATE
AFTERNOON AND OVERNIGHT HOURS. THE LOWEST CIGS AND GREATEST
SNOWFALL ACCUMULATION WILL BE ACROSS THE BORDERLAND AND INTO THE
ARROWHEAD REGION...INCLUDING THE KINL AND KHIB TERMINALS.

.PREV DISCUSSION... /ISSUED 402 AM CST SAT NOV 24 2012/

SHORT TERM...TODAY THROUGH SUNDAY.

LONG TERM MODELS CONTINUE TO SHOW ANOTHER SHORT WAVE DROPS OUT OF
CANADA AND SWEEPS OVER THE NORTHLAND MID-WEEK. HAVE KEPT SMALL POPS
IN THE NRN ZONES TUESDAY.

.POINT TEMPS/POPS...
DLH 24 16 25 9 / 50 70 10 0
INL 25 14 20 8 / 80 70 10 10
BRD 26 17 25 7 / 20 30 10 0
HYR 27 17 29 10 / 20 60 10 0
ASX 28 20 31 16 / 30 70 10 20

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&

SHORT TERM...DAP
LONG TERM....GRANING
AVIATION...GRANING

AREA FORECAST DISCUSSION

NWS DULUTH MN

402 AM CST SAT NOV 24 2012

.SHORT TERM...TODAY THROUGH SUNDAY.

.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY.
NW FLOW WILL BRING A CONTINUED CAA REGIME THROUGH THE WEEKEND.
MODELS ARE IN GOOD AGREEMENT THAT H85 TEMPS FALL INTO THE NEGATIVE
UPPER TEENS TO AROUND NEGATIVE 20 C EARLY MONDAY MORNING. HAVE
LOWERED TEMPS SUNDAY NIGHT AND MONDAY TO ACCOUNT FOR THIS COLD AIR.
THE NW TRAJECTORIES AND COLD H85 TEMPS WILL BRING AN OPPORTUNITY FOR
LK EFFECT SNOW ALONG THE SOUTH SHORE OF LK SUPERIOR SUNDAY NIGHT
INTO MONDAY WHERE LIGHT SNOW ACCUMULATION WILL BE POSSIBLE ALONG THE
GOGEBIC RANGE. LATEST NAM BUFR SOUNDINGS SHOW THE STEEP LAPSE RATES
ASSOCIATED WITH THE COLD AIR...AND A SHALLOW LAYER OF
MOISTURE...REMAINS OVER THE ARROWHEAD ZONES THROUGH SUNDAY NIGHT
WHERE FLURRIES OR VERY LIGHT SHSN MAY LINGER.

LONG TERM MODELS CONTINUE TO SHOW ANOTHER SHORT WAVE DROPS OUT OF
CANADA AND SWEEPS OVER THE NORTHLAND MID-WEEK. HAVE KEPT SMALL POPS
IN THE NRN ZONES TUESDAY.

.AVIATION.../06Z TAF ISSUANCE/
COLD NWLY FLOW ALOFT WILL ALLOW INTERMITTENT BKN IFR/MVFR CIGS
AROUND BRD/HIB/DLH TONIGHT WITH PERIODS OF LIGHT SNOW POSSIBLE.
HYR WILL REMAIN UNDER LOW-END MVFR CIGS TONIGHT WITH FLURRIES. INL
SHOULD REMAIN SKC WITH MUCH DRIER AIR TO THE NORTH. HIGH PRESSURE
WILL MOVE ACROSS THE REGION TONIGHT AND AID IN THE CLEARING
SOMEWHAT...BUT BE QUICKLY OVERTAKEN BY THE NEXT LOW PRESSURE
SYSTEM MOVING IN FROM THE WEST BY EARLY FRI AFTERNOON. WILL SEE
-SN DEVELOP AND CIGS DROP BY 20Z FRIDAY AROUND BRD/INL...AND
SHORTLY AFTER AT HIB AND DLH. BEST CHC OF ACCUMULATING SNOW WILL
BE ACROSS THE NORTH...WITH REDUCED IFR VSBYS POSSIBLE AS WELL
EARLY FRI EVENING. WINDS SHOULD REMAIN LESS THAN 15 KTS.

.POINT TEMPS/POPS...
DLH 24 16 25 9 / 50 70 10 0
INL 25 14 20 8 / 80 70 10 10
BRD 26 17 25 7 / 20 30 10 0
HYR 27 17 29 10 / 20 60 10 0
ASX 28 20 31 16 / 30 70 10 20

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&

SHORT TERM...DAP
LONG TERM....GRANING
AVIATION...TENTINGER

AREA FORECAST DISCUSSION

NWS BILLINGS MT

844 PM MST SUN NOV 25 2012

.SHORT TERM...VALID FOR MON AND TUE...

THE FORECAST IS LARGELY ON TRACK THIS EVENING...THOUGH WE DID MAKE
A FEW SMALL ADJUSTMENTS TO KEEP SLIGHT CHANCE POPS IN PLACE BEYOND
06 UTC FOR MORE OF SOUTH CENTRAL MT...AND TO INCREASE THE COVERAGE
OF FOG FROM 06 TO 18 UTC. OUT OF RESPECT TO THE POTENTIAL FOG...WE
CHOSE TO INCREASE LOW TEMPERATURES A BIT IN SOME AREAS TOO. THE 00
UTC NAM AND 02 UTC RAP SOLUTIONS BACKED UP THAT DECISION.

AS OF 03 UTC...THE BACK EDGE OF RELATIVELY SIGNIFICANT SNOW SHOWER
ACTIVITY IS MAKING ITS WAY THROUGH BILLINGS. THIS PRECIPITATION IS
BEING DRIVEN BY A HEALTHY AREA OF 300-500 HPA Q-VECTOR CONVERGENCE
TIED TO A MODEST SHORT WAVE TROUGH IN AN ENVIRONMENT CHARACTERIZED
BY STEEP MID-LEVEL LAPSE RATES. THE 18 AND 00 UTC MODELS PICKED UP
ON THIS SCENARIO...AND THEY ALL TAKE THE Q-VECTOR CONVERGENCE INTO
THE SHERIDAN AREA BY AROUND 06 UTC...WHICH LINES UP WITH TRENDS IN
RADAR DATA AS OF MID EVENING. WE PICKED UP A SOLID INCH OF SNOW IN
DOWNTOWN BILLINGS WITH THIS ACTIVITY...SO IT STANDS TO REASON THAT
BIG HORN AND SHERIDAN COUNTIES WILL SEE ANOTHER INCH OR TWO AS THE
SHORT WAVE DROPS DOWN INTO THOSE AREAS TOO. THUS WE WILL LEAVE OUR
WINTER WEATHER ADVISORY IN PLACE UNTIL THE 4 AM FORECAST. WE CHOSE
TO LEAVE THE ADVISORY UP FOR THE BEARTOOTH AND RED LODGE FOOTHILLS
AS WELL SINCE THERE IS LIGHT SNOW ONGOING THERE AS OF 03 UTC...BUT
IT IS NOT CLEAR THEY WILL GET MUCH MORE ACCUMULATION OVERNIGHT. WE
ALSO USED MID-EVENING RADAR TRENDS AS THE BASIS FOR KEEPING SLIGHT
CHANCES OF SNOW IN PLACE AFTER 06 UTC FOR PLACES LIKE BILLINGS.

WHERE FOG IS CONCERNED...A RELATIVELY MOIST BOUNDARY LAYER AND THE
ONSET OF CLEARING OVERNIGHT BOTH ARGUE FOR ITS FORMATION. THIS HAS
ALREADY OCCURRED UPSTREAM IN PLACES LIKE GREAT FALLS...AND IN FACT
THE VISIBILITY THERE HAS FALLEN TO A QUARTER OF A MILE. WE BELIEVE
BILLINGS COULD BE IN A PRETTY GOOD POSITION FOR FOG...PARTICULARLY
UP ON THE RIMS AS A LIGHT SOUTH-SOUTHWEST WIND DEVELOPS BY 12 UTC.
HOWEVER...IT IS INTERESTING TO NOTE THAT FORECAST SOUNDINGS SHOW A
MODESTLY MIXED NEAR-SURFACE LAYER CONTINUING OVERNIGHT...WHICH WAS
ENOUGH TO MAKE SOME BUFKIT-BASED ALGORITHMS CALL FOR STRATUS...AND
NOT FOG. SCHULTZ

.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...

MODELS OVERALL IN PRETTY GOOD AGREEMENT THROUGH NEXT WEEKEND...
THOUGH WITH SOME SMALL DETAILS TO BE WORKED OUT. HAVE MADE LITTLE
CHANGE TO THE FORECAST TODAY.

UPPER LEVEL RIDGE WILL REMAIN OVER THE REGION WEDNESDAY...
RESULTING IN DRY WX FOR US...BUT SHORTWAVE IN CANADA COMBINED WITH
A RIDGE AXIS TO OUR WEST AND SLIGHTLY CONFLUENT FLOW ALOFT MAY
RESULT IN A BACKDOOR FRONT GETTING INTO SOUTHEAST MONTANA EITHER
WEDNESDAY AFTERNOON OR EVENING. MODELS HAVE TRENDED A BIT MORE
AGGRESSIVE HERE...SO HAVE BROUGHT IN EAST WINDS AND COOLED TEMPS
SLIGHTLY WEDNESDAY NIGHT. THIS DESERVES TO BE WATCHED AS IF THE
BACKDOOR COOLING IS STRONG ENOUGH A COOLER AIRMASS MAY LINGER INTO
THURSDAY...AS THE CANADIAN SUGGESTS...THOUGH WOULD EXPECT WEAK
WEDNESDAY NIGHT SHORTWAVE TO HELP SHIFT THE SFC TROF BACK TO THE
EAST BY THEN. WILL KEEP LOW POPS FOR OUR WESTERN MOUNTAINS PER
THIS PACIFIC ENERGY...A FEATURE WHICH WILL BE KICKED EAST BY
DEVELOPING DEEPER TROF OFF THE PACIFIC COAST.

SOUTHWEST-WEST FLOW ALOFT WILL SET UP FOR THE FRIDAY-SUNDAY
PERIOD WITH A LOW HEIGHT ANOMALY REMAINING OFF THE COAST. THIS
PATTERN WITH A MOISTENING PACIFIC FLOW WILL FAVOR OUR WESTERN
SLOPES THE MOST AND WILL KEEP HIGHEST POPS OVER THE BEARTOOTH
ABSAROKAS DURING THIS PERIOD. THERE WILL PROBABLY BE A COUPLE
SHORTWAVES EMBEDDED IN THIS FLOW THAT COULD BRING A FEW SHOWERS
TO THE LOWER ELEVATIONS BRIEFLY...PERHAPS FRIDAY AND SUNDAY...BUT
BIGGER IMPACT WILL LIKELY BE WIND. WILL KEEP SLIGHT CHANCE POPS
FOR THE WESTERN LOWER ELEVATIONS...AND WILL NEED TO KEEP A WATCH
FOR ANY PERIODS OF ENHANCED WINDS.

TEMPS WILL GENERALLY REMAIN ABOVE NORMAL...AGAIN PENDING BACKDOOR
FRONT WEDNESDAY NIGHT...WITH HIGHS IN THE MID 40S TO MID 50S AND
MILD NIGHTS PER SOME WIND AND CLOUD COVER. COULD SEE A WARMER
PREFRONTAL DAY BY SUNDAY IF THE LATEST MODEL RUNS VERIFY.

JKL

.AVIATION...

AREAS OF MODERATE SNOW SHOWERS WILL CONTINUE TO AFFECT SOUTHERN
MONTANA AND THE NORTHERN WYOMING REGION OF THE BIG HORNS THROUGH
AROUND 07Z. IFR TO LOCAL LIFR CAN BE EXPECTED IN THE HEAVIER SNOW
SHOWERS. THE PRECIPITATION WILL TAPER OFF LATE...BUT FOG IS
EXPECTED TO DEVELOP AND SPREAD ACROSS THE AREA BY MORNING. EXPECT
WIDESPREAD MVFR TO IFR FLIGHT CONDITIONS...WITH LOCALIZED
LIFR/VLIFR DUE TO FOG. THESE REDUCTIONS WILL BE MOST LIKELY AT
SITES KBIL...KSHR AND KMLS. EARLY MORNING AIRPORT OPERATIONS MAY
VERY WELL BE SIGNIFICANTLY IMPACTED AT KBIL MONDAY. BT

.PRELIMINARY POINT TEMP/POPS...

MON TUE WED THU FRI SAT SUN
-----------------------------------------------------------
BIL 021/036 024/046 028/052 028/052 032/055 033/052 037/054
60/F 00/B 00/B 00/B 00/B 11/B 12/W
LVM 014/035 018/047 029/051 029/050 032/052 032/050 034/049
40/N 00/N 00/N 21/N 12/W 22/W 22/W
HDN 022/037 019/048 021/049 024/051 026/051 029/053 031/055
61/F 00/B 00/B 00/B 00/B 11/B 11/B
MLS 016/036 019/041 022/045 022/046 027/050 029/050 031/051
41/F 00/B 00/B 01/B 00/B 11/B 11/B
4BQ 019/035 020/045 021/049 024/048 026/051 027/052 029/055
71/B 00/B 00/B 00/B 00/U 00/B 00/B
BHK 014/034 018/041 020/046 019/041 025/046 029/048 030/050
21/F 00/B 00/B 00/B 00/U 11/B 11/U
SHR 021/035 016/049 022/051 024/049 027/052 029/051 030/055
+1/F 00/U 00/B 00/B 00/B 00/B 01/B

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 AM MST MONDAY FOR
ZONES 38-56-66.
WY...WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 AM MST MONDAY FOR
ZONES 98-99.

$$
WEATHER.GOV/BILLINGS

AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

1044 PM EST SUN NOV 25 2012

.SYNOPSIS...
LAKE EFFECT SNOWS WILL IMPACT THE TUG HILL PLATEAU REGION
TONIGHT...AND THEN DROP BACK SOUTH TO COVER MORE OF CENTRAL NEW
YORK WITH SNOW SHOWERS FOR THE FIRST HALF OF MONDAY. SNOW SHOWERS
DIMINISH FOR A TIME MONDAY AFTERNOON...BEFORE A FAST MOVING LOW PRESSURE
SYSTEM BRINGS A PERIOD OF LIGHT SNOW AND FLURRIES TO NORTHERN
PENNSYLVANIA AND SOUTHERN NEW YORK LATE MONDAY NIGHT AND EARLY
TUESDAY. TEMPERATURES WILL REMAIN BELOW NORMAL THROUGH MIDWEEK.

.NEAR TERM /THROUGH MONDAY/...
1030 PM UPDATE...
LAKE BAND CONTINUING TO MOVE NORTH THIS HR AS EVIDENCED ON LATEST
RADAR TRENDS. FURTHER SOUTH...GENERAL LIGHT SYNOPTIC SNOW
CONTINUING TO ALSO FALL ACROSS PORTIONS OF THE FINGER LAKES AND
SUSQUEHANNA VALLEY REGIONS OF CENTRAL NEW YORK. SYNOPTIC ACTIVITY
IS BEING FORCED BY THE COMBINATION OF A WEAK SHEARED OUT SHORTWAVE
TRAVELING OVER THE REGION AND INCREASING WARM AIR ADVECTION IN
ADVANCE OF A WEAK SFC LOW TRAVELING THROUGH SOUTHERN CANADA. THAT
SAID...SYNOPTIC ACTIVITY WILL COME TO AN END IN THE NEXT FEW HRS
WITH ALL ATTENTION REMAINING ON LAKE EFFECT ACTIVITY EAST OF LAKE
ONTARIO.

18Z LOCALLY RUN WRF AND LATEST RAPID REFRESH (FORMALLY THE RUC)
ACCURATELY SHOWING THE NORTHWARD MOVEMENT OF THE BAND OVER THE
PAST FEW HRS. THIS IS OCCURRING AS THE LOW-LEVEL FLOW BACKS IN
ADVANCE OF THE AFOREMENTIONED SFC LOW TRAVELING TO OUR NORTH.
UPSTREAM OBSERVATIONS ACROSS SOUTHERN ONTARIO AND EASTERN MI
SHOWING A GRADUAL WIND SHIFT TO THE WNW BEHIND THE LOW. GIVEN
THIS SCENARIO...WE EXPECT THE LAKE BAND TO GRADUALLY BEGIN
SHIFTING SOUTH AFTER 09Z AS WINDS VEER BEHIND THE FEATURE. ONCE
THIS OCCURS...LAKE BAND CHARACTERIZED BY HOURLY SNOWFALL RATES OF
OVER 1"/HR WILL MOVE BACK INTO NORTHERN ONEIDA COUNTY WHERE
ADDITIONAL SNOWFALL MAY PUSH STORM TOTALS OVER THE 10-12" MARK.
SNOWS WILL CONTINUE THROUGH A GOOD PORTION OF THE MORNING HRS
ACROSS CENTRAL AND NORTHERN ONEIDA COUNTY BEFORE DRIER AIR MOVES
INTO THE REGION TOWARDS MIDDAY...ULTIMATELY DECREASING LAKE EFFECT
INTENSITY AND ORGANIZATION. REMAINDER OF THE FCST AREA OUTSIDE OF
LAKE ACTIVITY SHOULD SEE MAINLY DRY CONDITIONS THROUGH THE DAY ON
MONDAY WITH HIGH TEMPS TOPPING OUT IN THE MIDDLE TO UPPER 30S.

745 PM UPDATE... SINGLE LAKE EFFECT BAND EAST OF LAKE ONTARIO
ONGOING THIS HR WITH RADAR INDICATIONS SUGGESTING BAND IS
BEGINNING LIFT NORTH AS EXPECTED. NORTHWARD SHIFT IS THE RESULT OF
BACKING LOW-LEVEL FLOW IN ADVANCE OF A WEAK AREA OF LOW PRESSURE
NOW MOVING THROUGH SOUTHERN ONTARIO. WITH TIME OVERNIGHT...MAIN
BAND IS AGAIN EXPECTED TO BEGIN DRIFTING SOUTH AS WINDS BEGIN
VEERING BEHIND DEPARTING SFC WAVE. LATEST MODEL TRENDS FROM BOTH
THE LOCALLY RUN WRF AND RR SHOW SOUTHWARD MIGRATION AFTER 06Z
FAIRLY WELL AS FLOW AGAIN AGAIN BECOMES WEST-NORTHWESTERLY. NO
RECENT SNOWFALL REPORTS HOWEVER REPORTS EARLIER THIS EVENING
INDICATED THAT SNOWFALL TOTALS WERE RAPIDLY APPROACHING 6". AS THE
BAND DRIFTS SOUTH INTO THE REGION AGAIN AFTER MIDNIGHT...HOURLY
SNOWFALL RATES OF 2-3"/HR WILL BE POSSIBLE UNDER THE MOST INTENSE
PART OF THE BAND...BRINGING STORM TOTAL SNOWFALLS IN THE 10-15"
RANGE BEFORE ALL IS SAID AND DONE EARLY MON AFTERNOON. WILL
CONTINUE TO ADJUST SNOWFALL FCST AS NEW MODEL GUIDANCE COMES IN.
ELSEWHERE...REGIONAL RADARS DEPICTING -SN ACROSS MUCH OF CENTRAL
NY AS ASSOCIATED UPPER SHORTWAVE MOVES OVER THE REGION. LITTLE TO
NO SNOW ACCUMULATIONS ARE EXPECTED WITH THIS ACTIVITY HOWEVER AS
ALL ACCUMULATIONS WILL BE CONFINED TO THE SINGLE LAKE BAND EAST OF
LAKE ONTARIO.

445 PM UPDATE... HAVE RECEIVED A FEW REPORTS OF OVER SIX INCHES
OF SNOW ACROSS NORTHERN PORTIONS OF ONEIDA COUNTY. LATEST RADAR
TRENDS SHOW A WELL DEVELOPED LAKE BAND EXTENDING INLAND FROM LAKE
ONTARIO...WITH LITTLE INDICATION SNOWS WILL STOP ANYTIME SOON.
BAND WILL LIKELY LIFT NORTH OF THE AREA FOR A TIME LATER THIS
EVENING BEFORE SHIFTING SOUTH ACROSS NORTHERN ONEIDA COUNTY ONCE
AGAIN AS WINDS AGAIN BECOME WESTERLY AFTER MIDNIGHT. THAT
SAID...HAVE DECIDED TO UPGRADE THE ADVISORY TO A WARNING AS
ADDITIONAL ROUNDS OF SNOW COMBINED WITH SNOW THAT IS OCCURRING NOW
WILL LIKELY PUSH ACCUMULATIONS ABOVE WARNING CRITERIA. NEW WSW
ALREADY POSTED. WILL CONTINUE TO MONITOR.

PREVIOUS NEAR TERM DISCUSSION...
MADE SEVERAL CHANGES TO THE FCST FOR TODAY THROUGH TONIGHT.
NAMELY HAD TO ADJUST POPS HIGHER AS UPPER WAVE CAME IN FROM THE
WEST FOR A HIGH OCCURRENCE/LOW QPF EVENT WITH GENERALLY LIGHT
SNOW/FLURRIES ACROSS THE REGION. WITHIN THE GENERAL LIGHT SNOW
AREA REMAINS THE EMBEDDED LAKE BANDS...AND THE ONEIDA CENTRIC BAND
WAS BECOMING RE- ESTABLISHED ON A 280 FLOW PATTERN THIS AFTERNOON.
SOME REPORTS OF 2-3 INCHES HAVE BEEN RECEIVED FROM ROME NORTHWARD
SINCE THIS MORNING. BAND SHOULD BE ABLE TO PRODUCE ANOTHER FEW
INCHES THIS AFTERNOON AND EARLY EVENING BEFORE PULLING JUST NORTH
OF THE COUNTY LATER IN THE EVENING. FOLLOWED OUR LOCAL WRF MODEL
IN REGARDS TO TIMING AND PLACEMENT OF LIFT/MOISTURE AND QPF
FIELDS...ALTHOUGH NAM12 AND RAP MODEL BUFKIT FIELDS ARE
COMPARABLE. THE BAND THEN LOOKS TO COME BACK IN JUST PRIOR TO
DAYBREAK MONDAY WITH ANOTHER FEW INCHES POSSIBLE. SHEAR ALONG WITH
WEAKENING FLOW AND DIURNAL DISRUPTION OF THE LAKE INSTABILITY
PROCESSES ALLOW FOR WEAKENING MONDAY AFTERNOON WITH NOMINAL
ACCUMS.

SEE LITTLE VARIATION IN TEMPERATURES WITH LOWS IN THE UPR 20S
TONIGHT AND HIGHS MONDAY GENERALLY MID 30S.

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
NEXT ITEM TO FOCUS ON WILL BE APPROACHING OPEN WAVE AND WEAK LOW
PRESSURE ON MONDAY NIGHT AND EARLY TUESDAY. THIS LOOKS TO BE A
RATHER MINIMAL EVENT WITH SNOW BREAKING OUT OVER THE LOWER OH/TN
VALLEY REGION DUE TO ISENTROPIC LIFT AHEAD OF THE UPPER WAVE WHICH
THEN LIFTS NORTH INTO MAINLY THE SOUTHERN HALF OF NY AND NEPA.
GFS/NAM IN REASONABLE AGREEMENT THAT WE NEED TO SPEED UP TIMING BY
A GOOD 6 HOURS AS WAA PRECIP DOES TEND TO DEVELOP QUICKER AND
THESE TRENDS SUPPORT THAT. WILL BRING IN LIGHT SNOW BETWEEN 06Z-12Z
TUESDAY...WITH A QUICK HITTING EVENT THAT APPEARS TO BE OUT OF THE
PICTURE BY EARLY AFTERNOON. THIS...ALONG WITH MARGINAL TEMPERATURES
AND MINIMAL LIFT SHOULD BE A LIGHT EVENT WITH NOMINAL ACCUMULATIONS
RANGING FROM A DUSTING TO AN INCH...POSSIBLY 2 INCHES IN THE
MOUNTAINS OF NEPA. THE NORTHERN EXTENT LOOKS TO BE AROUND THE
SOUTHERN TIER OF NY...WITH POSSIBLY A FEW FLURRIES UP NORTH.

HIGH PRESSURE THEN BUILDS IN FROM THE SOUTHWEST...BUT BROAD
CYCLONIC FLOW ALOFT AND INCREASING LOW LEVEL MOISTURE ON NWLY LOWER
ATMOSPHERE FLOW SHOULD SPELL A BROAD AREA OF FLURRIES DEVELOPING
BY WEDNESDAY AFTERNOON.

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
GFS/ECMWF IN GOOD AGREEMENT THROUGH THURSDAY... THEN SOME
DIFFERENCES DEVELOP WITH THE NEXT SYSTEM APPROACHING THE AREA FROM
THE MIDWEST. WEDNESDAY NIGHT THROUGH THURSDAY WILL BE COLD WITH
SCATTERED SNOW SHOWERS NEAR LAKE ONTARIO... OTHERWISE DRY. THE GFS
BRINGS PRECIPITATION ASSOCIATED WITH THE NEXT SYSTEM FRIDAY NIGHT
AND SATURDAY... WHILE THE ECMWF IS MUCH SLOWER AND MORE AMPLIFIED
WITH THIS SYSTEM... NOT BRINGING ANY PRECIPITATION INTO THE AREA
UNTIL AROUND SUNDAY. AT THIS POINT HAVE GONE WITH THE HPC SCENARIO
WHICH FAVORS THE SLOWER ECMWF. BASED ON THIS HAVE KEPT
PRECIPITATION OUT OF THE FORECAST THROUGH SATURDAY. TEMPERATURES
THURSDAY THROUGH SATURDAY WILL BE NEAR TO SLIGHTLY BELOW NORMAL...
WITH HIGHS MAINLY IN THE 30S AND LOWS IN THE 20S.

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
MAIN WX FEATURE THIS EVENING IS THE LE SNOW BAND OVER NRN NY. MAIN
BODY OF THE BAND WILL STAY NORTH OF RME AND SYR FOR THE NEXT SVRL
HRS...WITH JUST SOME SCT SNOW SHWRS DRFTG THRU SOUTH OF THE BAND.
LTR TNGT AND EARLY ON MON...BAND WILL DRIFT SWRD AND BRING IFR
CONDS TO RME AND YR FOR A FEW HRS BEFORE WEAKENING LTR IN THE DAY.
TO THE SOUTH...ITH/BGM/ELM WILL REMAIN VFR OR MVFR THRU THE TAF PD
WITH SCT SNOW SHWRS. BETTER CHANCE OF LWRD CONDS RETURNS ON MON AS
SOME PIECES OF THE NRN BAND DRIFT THRU. AVP IS WELL SOUTH OF THE
ACTIVITY WILL REMAIN VFR THRU THE PD.

OUTLOOK...

TUE...VFR-MVFR WITH CHC IFR AS STORM SYSTEM SLIDES JUST TO THE
SOUTH...ESPECIALLY AVP AND BGM.

WED...VFR-MVFR WITH CHC IFR IN LAKE SNOW SHOWERS...MAINLY CNTRL NY.

THU/FRI...VFR.

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 1 PM EST MONDAY FOR NYZ009.

$$
SYNOPSIS...JAB
NEAR TERM...CMG/JAB
SHORT TERM...JAB
LONG TERM...MSE
AVIATION...DGM/MSE

AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

757 PM EST SUN NOV 25 2012

.NEAR TERM /THROUGH MONDAY/...
745 PM UPDATE...
SINGLE LAKE EFFECT BAND EAST OF LAKE ONTARIO ONGOING THIS HR WITH
RADAR INDICATIONS SUGGESTING BAND IS BEGINNING LIFT NORTH AS
EXPECTED. NORTHWARD SHIFT IS THE RESULT OF BACKING LOW-LEVEL FLOW
IN ADVANCE OF A WEAK AREA OF LOW PRESSURE NOW MOVING THROUGH
SOUTHERN ONTARIO. WITH TIME OVERNIGHT...MAIN BAND IS AGAIN
EXPECTED TO BEGIN DRIFTING SOUTH AS WINDS BEGIN VEERING BEHIND
DEPARTING SFC WAVE. LATEST MODEL TRENDS FROM BOTH THE LOCALLY RUN
WRF AND RR SHOW SOUTHWARD MIGRATION AFTER 06Z FAIRLY WELL AS FLOW
AGAIN AGAIN BECOMES WEST-NORTHWESTERLY. NO RECENT SNOWFALL REPORTS
HOWEVER REPORTS EARLIER THIS EVENING INDICATED THAT SNOWFALL
TOTALS WERE RAPIDLY APPROACHING 6". AS THE BAND DRIFTS SOUTH INTO
THE REGION AGAIN AFTER MIDNIGHT...HOURLY SNOWFALL RATES OF 2-3"/HR
WILL BE POSSIBLE UNDER THE MOST INTENSE PART OF THE BAND...BRINGING
STORM TOTAL SNOWFALLS IN THE 10-15" RANGE BEFORE ALL IS SAID AND
DONE EARLY MON AFTERNOON. WILL CONTINUE TO ADJUST SNOWFALL FCST AS
NEW MODEL GUIDANCE COMES IN. ELSEWHERE...REGIONAL RADARS DEPICTING
-SN ACROSS MUCH OF CENTRAL NY AS ASSOCIATED UPPER SHORTWAVE MOVES
OVER THE REGION. LITTLE TO NO SNOW ACCUMULATIONS ARE EXPECTED WITH
THIS ACTIVITY HOWEVER AS ALL ACCUMULATIONS WILL BE CONFINED TO
THE SINGLE LAKE BAND EAST OF LAKE ONTARIO.

SEE LITTLE VARIATION IN TEMPERATURES WITH LOWS IN THE UPR 20S
TONIGHT AND HIGHS MONDAY GENERALLY MID 30S.

.AVIATION /01Z MONDAY THROUGH FRIDAY/...
MAIN WX FEATURE THIS EVENING IS THE LE SNOW BAND OVER NRN NY. MAIN
BODY OF THE BAND WILL STAY NORTH OF RME AND SYR FOR THE NEXT SVRL
HRS...WITH JUST SOME SCT SNOW SHWRS DRFTG THRU SOUTH OF THE BAND.
LTR TNGT AND EARLY ON MON...BAND WILL DRIFT SWRD AND BRING IFR
CONDS TO RME AND YR FOR A FEW HRS BEFORE WEAKENING LTR IN THE DAY.
TO THE SOUTH...ITH/BGM/ELM WILL REMAIN VFR OR MVFR THRU THE TAF PD
WITH SCT SNOW SHWRS. BETTER CHANCE OF LWRD CONDS RETURNS ON MON AS
SOME PIECES OF THE NRN BAND DRIFT THRU. AVP IS WELL SOUTH OF THE
ACTIVITY WILL REMAIN VFR THRU THE PD.

OUTLOOK...

TUE...VFR-MVFR WITH CHC IFR AS STORM SYSTEM SLIDES JUST TO THE
SOUTH...ESPECIALLY AVP AND BGM.

WED...VFR-MVFR WITH CHC IFR IN LAKE SNOW SHOWERS...MAINLY CNTRL NY.

THU/FRI...VFR.

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 1 PM EST MONDAY FOR NYZ009.

$$
SYNOPSIS...JAB
NEAR TERM...CMG/JAB
SHORT TERM...JAB
LONG TERM...MSE
AVIATION...DGM/MSE

AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

645 PM EST SUN NOV 25 2012

.NEAR TERM /THROUGH MONDAY/...
445 PM UPDATE...
HAVE RECEIVED A FEW REPORTS OF OVER SIX INCHES OF SNOW ACROSS
NORTHERN PORTIONS OF ONEIDA COUNTY. LATEST RADAR TRENDS SHOW A
WELL DEVELOPED LAKE BAND EXTENDING INLAND FROM LAKE ONTARIO...WITH
LITTLE INDICATION SNOWS WILL STOP ANYTIME SOON. BAND WILL LIKELY
LIFT NORTH OF THE AREA FOR A TIME LATER THIS EVENING BEFORE
SHIFTING SOUTH ACROSS NORTHERN ONEIDA COUNTY ONCE AGAIN AS WINDS
AGAIN BECOME WESTERLY AFTER MIDNIGHT. THAT SAID...HAVE DECIDED TO
UPGRADE THE ADVISORY TO A WARNING AS ADDITIONAL ROUNDS OF SNOW
COMBINED WITH SNOW THAT IS OCCURRING NOW WILL LIKELY PUSH
ACCUMULATIONS ABOVE WARNING CRITERIA. NEW WSW ALREADY POSTED. WILL
CONTINUE TO MONITOR.

SEE LITTLE VARIATION IN TEMPERATURES WITH LOWS IN THE UPR 20S
TONIGHT AND HIGHS MONDAY GENERALLY MID 30S.

.AVIATION /00Z MONDAY THROUGH FRIDAY/...

MAIN WX FEATURE THIS EVENING IS THE LE SNOW BAND OVER NRN NY. MAIN
BODY OF THE BAND WILL STAY NORTH OF RME AND SYR FOR THE NEXT SVRL
HRS...WITH JUST SOME SCT SNOW SHWRS DRFTG THRU SOUTH OF THE BAND.
LTR TNGT AND EARLY ON MON...BAND WILL DRIFT SWRD AND BRING IFR
CONDS TO RME AND YR FOR A FEW HRS BEFORE WEAKENING LTR IN THE DAY.
TO THE SOUTH...ITH/BGM/ELM WILL REMAIN VFR OR MVFR THRU THE TAF PD
WITH SCT SNOW SHWRS. BETTER CHANCE OF LWRD CONDS RETURNS ON MON AS
SOME PIECES OF THE NRN BAND DRIFT THRU. AVP IS WELL SOUTH OF THE
ACTIVITY WILL REMAIN VFR THRU THE PD.

OUTLOOK...

TUE...VFR-MVFR WITH CHC IFR AS STORM SYSTEM SLIDES JUST TO THE
SOUTH...ESPECIALLY AVP AND BGM.

WED...VFR-MVFR WITH CHC IFR IN LAKE SNOW SHOWERS...MAINLY CNTRL NY.

THU/FRI...VFR.

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 1 PM EST TUESDAY FOR NYZ009.

$$
SYNOPSIS...JAB
NEAR TERM...CMG/JAB
SHORT TERM...JAB
LONG TERM...MSE
AVIATION...DGM/MSE

AREA FORECAST DISCUSSION...UPDATED

NWS GRAND FORKS ND

859 PM CST SUN NOV 25 2012

.DISCUSSION...
MAIN ISSUE TONIGHT IS TEMPERATURES. FOREAST GOING ABOUT AS
EXPECTED WITH MAIN CLEARING HAVING REACHED A COOPERSTOWN TO FARGO
TO WADENA LINE AT 0230Z. UPSTREAM SKIES MAINLY CLEAR THOUGH THERE
ARE SOME SMALL PATCHES OF STRATOCU AND A LITTLE CIRRUS. IN CLEAR
AREA OVER NRN ND INTO FAR NW MN WINDS HAVE DIMINISHED TO AROUND 5
KTS AND TEMPS ARE IN THE SINGLE DIGITS...MOSTLY LOWER SINGLE
DIGITS. THAT SAID IF A CLOUD PATCH DOES MOVE OVER TEMPS TO RISE A
FEW DEGREES. AS SKIES CLEAR IN SE ND DO EXPECT TEMPS TO FALL MORE
RAPIDLY THERE....THOUGH THE FAR SOUTHWEST FCST AREA (SOUTH OF A
VALLEY CITY TO WAHPETON LINE) HAVE NO SNOW COVER AND THUS WILL
STAY THE WARMEST.

GOING WITH LATEST RUC IT DOES BRING IN NEGATIVE TEENS FOR LOWS
INTO THE CANDO-LANGDON-PEMBINA AREAS AND WILL STICK WITH WHAT WE
HAVE GOING WHICH IS A BIT WARMER BUT STILL AROUND THAT -10 TO -12F
RANGE IN THAT REGION WITH LOWS CLOSER TO ZERO FROM ABOUT NEW
ROCKFORD TO MAYVILLE TO BEMIDJI WITH ABOVE ZERO TEMPS SOUTH OF
THAT AREA. AS USUAL WITH LOW TEMPS...YOU CAN EXPECT LOW TEMPS TO
VARY GIVEN TEMPEATURE SITE LOCATION AND EXACT CLOUD COVER. HIGH
PRESSURE AT 12Z WILL BE IN CNTRL ND SO IN FAVORABLE REGION FOR
COLDEST TEMPS.

SEEING SOME CLOUDS AND SNOW SHOWERS OFF LAKE OF THE WOODS SO KEPT
IN SNOW SHOWERS THRU 06Z AT BAUDETTE.

&&
.AVIATION...
TAF SITES WILL SEE A MAINLY CLEAR SKY OVERNIGHT INTO MONDAY
MORNING...THOUGH RANDOM PATCHES OF STRATOCU MAY BRIEFLY DROP SITES
INTO LOW END MVFR CAT. EXPECT INCREASE IN HIGH AND THEN MID LEVEL
CLOUDS MON AFTN AS NORTHWEST WINDS 5 TO 10 KTS TURN SOUTHWEST AND
THEN SOUTHERLY ON MONDAY.

.PREV DISCUSSION... /ISSUED 307 PM CST SUN NOV 25 2012/

SHORT TERM... /TONIGHT THROUGH WEDNESDAY/
FORECAST CHALLENGE FOR THIS SHORT TERM PERIOD WILL BE SKY COVER
AND ASSOCIATED TEMPERATURES. SHORT TERM MODELS IN GENERAL
AGREEMENT WITH SFC FEATURES AS NO MAJOR WX SYSTEMS WILL IMPACT THE
AREA. LOOKING AT RECENT STATS...THE COLDER GEM HAS A SLIGHT EDGE
OVER OTHER MODELS AND AM LEANING TOWARD A GEM SOLUTION FOR TEMPERATURES.

CURRENT SATELLITE SHOWING MUCH OF THE NORTHERN VALLEY AND
NORTHWEST MINNESOTA IS SEEING SOME SUNSHINE AND
CLEARING...ALTHOUGH SKIES ARE STILL SCATTERED TO BROKEN. THE
EVOLUTION OF THE CLEARING SKIES WILL BE A MAJOR FACTOR FOR
OVERNIGHT LOWS.

TONIGHT...COLDEST TEMPERATURES WILL BE ACROSS THE NORTH WHERE SOME
RADIATIONAL COOLING WILL OCCUR. SEEING DEWPOINTS IN NORTHERN SASK
AND MB IN THE 10 TO 15 BELOW RANGE. THIS DRIER AIR SHOULD WORK ITS
WAY SOUTH OVERNIGHT. THE COLDEST MODEL SOLUTION IS THE GEM...WHICH
PLUMMETS DEWPOINTS DOWN INTO THE 20S BELOW ZERO. MOST OTHER MODELS
WERE WARMER THAN OUR PREV FCST. GIVEN THE DRIER AIR UPSTREAM AND
CLEARING SKIES WORKING THEIR WAY SOUTH...WILL LEAN TOWARD COLDER
GEM BUT NOT QUITE AS DRASTIC. LOOKING AT PARTS OF NORTHEAST ND TO
DROP INTO THE 8 TO 12 BELOW RANGE...CENTRAL ZONES IN THE ZERO TO
10 BELOW RANGE...AND ZERO TO FIVE ABOVE ACROSS THE SOUTH. THIS
WILL AGAIN BE VERY DEPENDENT ON SKY TRENDS.

MONDAY...WITH A COLD START TO THE DAY AND SOME CLOUD COVER...WILL BE
TOUGH FOR TEMPS TO CLIMB OUT OF THE MID TEENS. SOUTHWEST FLOW
WILL SET UP BY AFTN HOURS AND THE WARMEST TEMPS SHOULD BE IN THE
LOWER SHEYENNE VALLEY...WITH TEMPS BARELY TAPPING INTO THE 20S.
NORTHERN ZONES WILL SEE INCREASING CLOUD COVER AS A WEAK SYSTEM
MOVES ACROSS SOUTHERN CANADA.

MONDAY NIGHT INTO TUESDAY...WEAK SFC LOW WILL WORK ITS WAY ACROSS
CNTRL SASK/MB AND MODELS CONTINUE TO BRUSH SOME LIGHT PRECIP
ACROSS NORTHERN ZONES...WITH BEST CONFIDENCE OF ANY MEASURABLE
SNOWFALL IN THE FAR NORTHEAST. BEST ENERGY/LIFT WILL BE OVER SRN
CANADA...SO WITH LOW QPF VALUES EXPECT ANY SNOW ACCUMULATION TO BE
LESS THAN ONE INCH. SOUTHERN HALF OF CWA SHOULD SEE SOME SOLAR IN
ADDITION TO MODEST RETURN FLOW...ALLOWING TEMPS TO CLIMB INTO THE
UPPER 20S OR EVEN TAP INTO THE 30S IN THE FAR SOUTHERN VALLEY.

TUESDAY NIGHT AND WEDNESDAY...CANADIAN HIGH WILL DROP INTO THE
NORTHERN TIER AND TRANSIT THE CWA TUE NIGHT. THIS SHOULD BRING
FAIRLY CLEAR SKIES AND LIGHT WINDS. THUS EXPECTING ANOTHER COLD
NIGHT WITH TEMPS IN THE DOUBLE DIGITS BELOW ZERO POSSIBLE ACROSS
FAR NORTHERN ZONES. ONCE AGAIN LEANED TOWARD THE COLDER GEM
GUIDANCE FOR THIS TIME PERIOD. RETURN FLOW THEN SETS UP FOR
WEDNESDAY...ALLOWING TEMPS TO REBOUND INTO THE 20S BY WED AFTN.

LONG TERM...
MODELS ARE ALL IN FAIRLY GOOD AGREEMENT ON THE OVERALL PATTERN OF
NEAR ZONAL FLOW ALOFT AS AN UPPER LOW HANGS OFF THE WEST COAST...BUT
HAVE DIFFERENCES IN THE DETAILS. CONDITIONS SHOULD CONTINUE TO BE
FAIRLY COLD AT THE START OF THE PERIOD WITH COLD HIGH PRESSURE
WEDNESDAY NIGHT AND INTO THURSDAY. SEVERAL OF THE DETERMINISTIC
MODELS BREAK OUT SOME PRECIP IN THE NORTHERN COUNTIES
THURSDAY/THURSDAY NIGHT AS A WEAK SHORTWAVES MOVES THROUGH.
DIFFERENCES OF TIMING AND PLACEMENT ABOUND WITH THE GFS STRONGER AND
SLOWER THAN THE ECMWF AND GEM. ALLBLEND HAS SOME LOW POPS ALONG THE
CANADIAN BORDER AND THIS SEEMS REASONABLE GIVEN THE HIGH UNCERTAINTY
OF TIMING. TEMPS SHOULD BEGIN TO WARM SOMEWHAT FRIDAY AND INTO THE
WEEKEND AS HEIGHTS RISE OVER THE PLAINS. THE 12Z ECMWF BRINGS OUT A
FAIRLY SIGNIFICANT SHORTWAVE ON SATURDAY...WITH PLENTY OF PRECIP
OVER THE NORTHERN PLAINS. THE GFS IS MUCH WEAKER AND FURTHER
NORTH. GIVEN THAT THE 00Z RUN OF THE ECMWF WAS NOT NEARLY AS STRONG
WITH THE SATURDAY SYSTEM AND NAEFS MEMBERS SHOWING PRECIP ALL OVER
THE PLACE...WILL KEEP THE ALLBLEND SOLUTION OF A MORE NORTHERLY
SOLUTION FOR NOW BUT WILL KEEP A CLOSE EYE ON THE SYSTEM. SUNDAY
SHOULD BE QUIET BUT A BIT COOLER.

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$
RIDDLE/SPEICHER

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

700 AM EST SAT NOV 24 2012

.SYNOPSIS...
STRONG NORTHWEST WINDS AND COLD AIR CROSSING THE GREAT LAKES WILL
GENERATE LAKE EFFECT SNOW SHOWERS ACROSS THE WESTERN MOUNTAINS
INTO TONIGHT. FAST WEST-NORTHWEST FLOW ALOFT WILL BRING A COUPLE
OF WEAK LOW PRESSURE SYSTEMS ACROSS THE GREAT LAKES ON SUNDAY AND
AGAIN MONDAY. A WEAK TROUGH OF LOW PRESSURE WILL FORM OVER THE
LOWER MISSISSIPPI VALLEY ON MONDAY. AN AREA OF LOW PRESSURE COULD
DEVELOP AND SLIDE PRECIPITATION INTO THE REGION FROM THE
SOUTHWEST FOR MONDAY NIGHT INTO TUESDAY NIGHT.

.NEAR TERM /UNTIL 5 PM THIS AFTERNOON/...
LAKE EFFECT SNOW ADVISORY CONTINUES FOR WARREN AND MCKEAN
COUNTIES. A SLIGHT VEERING OF THE MEAN WIND HAS OCCURRED IN THE
LOWER LAYERS THIS MORNING. THIS HAS CHANGED THE CHARACTER OF THE
LAKE EFFECT SNOWS FROM THE EARLIER BROKEN CLUMP OF SHSN INTO MORE-
LINEAR BANDS. HOWEVER...THERE IS LITTLE ORGANIZATION TO THEM AT
1130Z. THERE IS A CONNECTION FROM LAKE HURON JUST SOUTH OF KBUF
AND INTO KELM. A SECOND WIDE/BROAD AREA OF CONVERGENCE TO THE
SOUTH OF THAT FROM KJHW INTO THE NRN MTS. THE BETTER-ALIGNED FLOW
IN THE LOW LEVELS WILL TRY TO MAKE THE PRECIP MORE BANDED THROUGH
THE DAY. BUT STRONG VERTICAL SPEED SHEAR AND SOME MEAGER DAYTIME
HEATING/MIXING WILL TRY TO COUNTERACT THAT TENDENCY. THUS...THE
CONVECTION WILL BE MORE CELLULAR THAN TRUE BANDS FOR MOST OF THE
AREA. THAT SAID...THE HIGH RES MODELS DO PLAY UP A HURON
CONNECTION WHICH COULD STRING MOD SNOW INTO THE CENTRAL MTS OR
EVEN THE POCONOS THIS AFTN. STILL...LITTLE ACCUMS ARE POSSIBLE OFF
THE ALLEGHENY PLATEAU AS TEMPS RISE INTO THE U30S/L40S AS YOU MOVE
OFF THE HIGHLANDS INTO THE SERN COS. THE SUBSIDENCE INVERSION
REMAIN BELOW 7KFT AT KBFD ALL DAY PER THE RUC FCST SOUNDINGS. THE
QPF REMAINS MEAGER WITH SREF AND DETERMINISTIC MODELS ALL MAKING
BETWEEN A TENTH AND TWO TENTHS OF AN INCH OF LIQUID TODAY. SLR/S
RUN GENERALLY 15:1 FOR THE DAY...BUT COULD BE 20:1 IN THE ADVY
AREA AS THE TOP OF THE CLOUDS APPEAR TO STAY IN THE GOOD DENDRITIC
GROWTH ZONE. THUS...WILL CONTINUE THE ADVY IN PLACE. HOWEVER...LOW
LEVEL AIR IS VERY DRY AND CIGS HIGHER THAN WHAT WOULD NORMALLY BE
EXPECTED FOR HEAVY SNOW. THIS AND THE TRANSIENT NATURE OF THE SHSN
TODAY WILL LIMIT THE ACCUMS...AND NO EXPANSION OF THE ADVY IS
NECESSARY. WINDS WILL MAKE IT FEEL VERY RAW...ESPECIALLY WITH
RESPECT TO THE RECENT MILD WEATHER WE HAVE EXPERIENCED.

.SHORT TERM /5 PM THIS AFTERNOON THROUGH MONDAY/...
THE NW FLOW CONTINUES INTO THE EVENING AND EARLY TONIGHT.
HOWEVER...THE 8H TEMPS DO START TO TURN UPWARD AFTER MIDNIGHT. THE
WINDS IN THE LOW LAYERS WILL BACK TO A MORE-SWRLY FLOW AS WELL.
THIS SHOULD DWINDLE THE SHSN...BUT SOME MAY LINGER INTO SUNDAY.
THE REAL ACCUMS SHOULD BE OVER BY MIDNIGHT. THE TOTALS BY THE END
OF THE EVENT WILL STRUGGLE TO MEET ADVY NUMBERS EXCEPT IN THE FAR
NWRN PART OF THE ADVY AREA...PLACES CLOSEST TO THE LAKE...DUE TO
THE SHORT FETCH EXPECTED FOR MUCH OF THE EVENT.

FLOW ALOFT REMAINS VERY FAST AND NWRLY ON SUNDAY. A CLIPPER-LIKE
SHORTWAVE DROPS ACROSS THE LAKES ON SUNDAY AND WILL MAKE SOME SHSN
IN THE NRN MTS AT THE NOSE OF SOME SLIGHT WAA. BUT THE GLANCING
BLOW IS HARDLY WORTH ANY MORE OF A MENTION. A NEW SHOT OF COLD AIR
MOVES DOWN FROM THE NW LATE MONDAY...BUT ANY MSTR ASSOCIATED WITH
IT SHOULD GET DRIED UP...AND PROBABLY NOT ARRIVE AFTER THIS SHORT
TERM PERIOD.

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS STILL HAVE SOME DIFFERENCES TO THE DEVELOPMENT OF A SYSTEM
WHICH WILL LIKELY IMPACT THE REGION MON NITE INTO TUESDAY. WHILE
THE 00Z ECMWF IS MORE GFS-LIKE NOW...THE OVERALL CONFIDENCE IN THE
MED RANGE FORECAST HAS GROWN ONLY A SLIGHT BIT. A WEAK INVERTED
TROUGH SHOULD DRAW MOISTURE NE FROM THE LOWER MS VALLEY MONDAY
NIGHT AND DEEPEN A LITTLE LOW OVER THE SRN APP MTS MONDAY
NIGHT/TUES. A GOOD DEAL OF QPF IS GENERATED TO THE NORTH OF THE
TRACK OF THIS WEAK SFC LOW BACK INTO THE COLD AIR OVER PA. THE EC
AND NAM SHOWS A WEAKER/FASTER LOW AND SHORTER TIME FRAME FOR
PRECIP OVER C PA. HAVE NUDGED THE FORECAST FOR MON NITE-TUES NITE
TOWARD THE CONGEALING CONSENSUS. THIS WILL PRETTY MUCH KEEP THE
FORECAST A 30-50 PCT CHANCE OF PRECIP IN THAT TIME FRAME AND MAKE
IT MORE SNOW P-TYPE THAN RAIN...SINCE A GENERALLY COLD SOLUTION IS
MORE LIKELY WITH THE SFC LOW TRACK/TROUGH TO THE S OF THE AREA.

NO CHANGES TO FCST FROM WED ONWARD.

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
GUSTY WEST TO NORTHWEST WINDS WILL PERSIST TODAY...AND BRING LAKE
EFFECT CLOUDS /STRATOCU/ TO MOST AIRFIELDS...THOUGH CIGS AFTER
SUNRISE SHOULD GENERALLY BE VFR EXCEPT AT BFD AND JST WHERE THEY
WILL REMAIN MVFR FOR SEVERAL HOURS THIS MORNING. FLURRIES AND ISOLD
SNOW SHOWERS WILL FLOW OFF THE LAKES AS WELL...BUT ANY HEAVY
ENOUGH TO CAUSE VSBY REDUCTIONS BELOW VFR SHOULD BE CONFINED TO BFD
AND JST.

IMPROVING CONDITIONS ARE EXPECTED THIS AFTERNOON THROUGH SUNDAY
AS WINDS SHIFT MORE TO THE WEST THIS AFTERNOON AND EVENING AND
THEN TO THE SW ON SUNDAY.

OUTLOOK... SUN...SHSN/MVFR CIGS NW MTNS...VFR ELSEWHERE.
MON- WED...VFR TO MVFR. CHC OF PCPN TUE-WED.

.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
PAZ004-005.

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...DANGELO/TYBURSKI
AVIATION...GARTNER/MARTIN

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

648 AM EST SAT NOV 24 2012

NO CHANGES TO FCST FROM WED ONWARD.

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
GUSTY NORTHWEST WINDS WILL PERSIST TODAY...AND BRING LAKE EFFECT
CLOUDS /STRATOCU/ TO MOST AIRFIELDS...AND SCT SNOW SHOWERS MAINLY
TO THE HIER ELEVATIONS SITES. VSBY/CIG REDUCTIONS LIKELY AT BFD
AND JST.

BFD AND JST WILL BOUNCE BACK AND FORTH BETWEEN VFR AND MVFR EARLY
THIS MORNING AS ROUNDS OF MAINLY LIGHT SNOW SHOWERS MOVE ACROSS.
LATEST RADAR AND 11-3.9 SATELLITE IMAGERY SHOW LATEST ROUND OF
THICKER CLOUDS REACHING LOWER SUSQ VALLEY...MDT/LNS...ATTM WITH
EVEN AN ISOLD FLURRY PSBL...BUT NO REDUCTIONS EXPECTED. UNV AND
AOO WILL SEE A FEW SNOW SHOWERS AND BRIEF MVFR CIGS AT TIMES.

IMPROVING CONDITIONS ARE EXPECTED FOR SUNDAY AS WINDS SHIFT MORE
TO THE WEST AND SW.

OUTLOOK...
SUN...SHSN/MVFR CIGS NW MTNS...VFR ELSEWHERE.
MON-WED...VFR TO MVFR. CHC OF PCPN TUE-WED.

.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
PAZ004-005.

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...DANGELO/TYBURSKI
AVIATION...GARTNER/MARTIN

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

502 AM EST SAT NOV 24 2012

.NEAR TERM /UNTIL 4 PM THIS AFTERNOON/...
LAKE EFFECT SNOW ADVISORY CONTINUES FOR WARREN AND MCKEAN
COUNTIES. A SLIGHT VEERING OF THE MEAN WIND HAS OCCURRED IN THE
LOWER LAYERS THIS MORNING. THIS HAS CHANGED THE CHARACTER OF THE
LAKE EFFECT SNOWS FROM THE EARLIER BROKEN CLUMP OF SHSN INTO MORE-
LINEAR BANDS. HOWEVER...THERE IS LITTLE ORGANIZATION TO THEM AT
09Z. THERE IS THE BEGINNING OF A CONNECTION FROM LAKE HURON
STARTING TO GO THROUGH KBUF WITH A SECOND WIDE/BROAD AREA OF
CONVERGENCE TO THE SOUTH OF THAT INTO THE NRN MTS. THE BETTER-
ALIGNED FLOW IN THE LOW LEVELS WILL HELP TO MAKE THE PRECIP MORE
BANDED THROUGH THE DAY. BUT STRONG VERTICAL SPEED SHEAR AND MEAGER
DAYTIME HEATING/MIXING WILL TRY TO COUNTERACT THAT TENDENCY.
THUS...THE CONVECTION WILL BE MORE CELLULAR THAN TRUE BANDS FOR
MOST OF THE AREA. THAT SAID...THE HIGH RES MODELS DO PLAY UP A
HURON CONNECTION WHICH COULD STRING MOD SNOW INTO THE CENTRAL MTS
OR EVEN THE POCONOS THIS AFTN. STILL...LITTLE ACCUMS ARE POSSIBLE
OFF THE ALLEGHENY PLATEAU AS TEMPS RISE INTO THE U30S/L40S AS YOU
MOVE OFF THE HIGHLANDS INTO THE SERN COS. THE SUBSIDENCE INVERSION
REMAIN BELOW 7KFT AT KBFD ALL DAY PER THE RUC FCST SOUNDINGS. THE
QPF REMAINS MEAGER WITH SREF AND DETERMINISTIC MODELS ALL MAKING
BETWEEN A TENTH AND TWO TENTHS OF AN INCH OF LIQUID TODAY. SLR/S
RUN GENERALLY 15:1 FOR THE DAY...BUT COULD BE 20:1 IN THE ADVY
AREA AS THE TOP OF THE CLOUDS APPEAR TO STAY IN THE GOOD DENDRITIC
GROWTH ZONE. THUS...WILL CONTINUE THE ADVY IN PLACE. HOWEVER...LOW
LEVEL AIR IS VERY DRY AND CIGS HIGHER THAN WHAT WOULD NORMALLY BE
EXPECTED FOR HEAVY SNOW. THIS AND THE TRANSIENT NATURE OF THE SHSN
TODAY WILL LIMIT THE ACCUMS...AND NO EXPANSION OF THE ADVY IS
NECESSARY. WINDS WILL MAKE IT FEEL VERY RAW...ESPECIALLY WITH
RESPECT TO THE RECENT MILD WEATHER WE HAVE EXPERIENCED.

.SHORT TERM /4 PM THIS AFTERNOON THROUGH MONDAY/...
THE NW FLOW CONTINUES INTO THE EVENING AND EARLY TONIGHT.
HOWEVER...THE 8H TEMPS DO START TO TURN UPWARD AFTER MIDNIGHT. THE
WINDS IN THE LOW LAYERS WILL BACK TO A MORE-SWRLY FLOW AS WELL.
THIS SHOULD DWINDLE THE SHSN...BUT SOME MAY LINGER INTO SUNDAY.
THE REAL ACCUMS SHOULD BE OVER BY MIDNIGHT. THE TOTALS BY THE END
OF THE EVENT WILL STRUGGLE TO MEET ADVY NUMBERS EXCEPT IN THE FAR
NWRN PART OF THE ADVY AREA...PLACES CLOSEST TO THE LAKE...DUE TO
THE SHORT FETCH EXPECTED FOR MUCH OF THE EVENT.

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS STILL HAVE SOME DIFFERENCES TO THE DEVELOPMENT OF A SYSTEM
WHICH WILL LIKELY IMPACT THE REGION MON NITE INTO TUESDAY. WHILE
THE 00Z ECMWF IS MORE GFS-LIKE NOW...THE OVERALL CONFIDENCE IN THE
MED RANGE FORECAST HAS GROWN ONLY A SLIGHT BIT. A WEAK INVERTED
TROUGH SHOULD DRAW MOISTURE NE FROM THE LOWER MS VALLEY MONDAY
NIGHT AND DEEPEN A LITTLE LOW OVER THE SRN APP MTS MONDAY
NIGHT/TUES. A GOOD DEAL OF QPF IS GENERATED TO THE NORTH OF THE
TRACK OF THIS WEAK SFC LOW BACK INTO THE COLD AIR OVER PA. THE EC
AND NAM SHOWS A WEAKER/FASTER LOW AND SHORTER TIME FRAME FOR
PRECIP OVER C PA. WILL STICK WITH GOING FCST WITHOUT MUCH CHANGE
IN FORECASTER CONFIDENCE. THIS WILL KEEP THE FORECAST A 30-50 PCT
CHANCE OF PRECIP FROM MON NIGHT INTO TUESDAY NIGHT...AND CHC RA OR
SN WORDING...BUT A GENERALLY COLD SOLUTION IS MORE LIKELY WITH THE
SFC LOW TRACK/TROUGH TO THE S OF THE AREA.

.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
GUSTY NORTHWEST WINDS WILL PERSIST TODAY...AND BRING LAKE EFFECT
CLOUDS /STRATOCU/ TO MOST AIRFIELDS...AND SCT SNOW SHOWERS MAINLY
TO THE HIER ELEVATIONS SITES. VSBY/CIG REDUCTIONS LIKELY AT BFD
AND JST.

IMPROVING CONDITIONS ARE EXPECTED FOR SUNDAY AS WINDS SHIFT MORE
TO THE WEST AND SW.

OUTLOOK...
SUN...SHSN/MVFR CIGS NW MTNS...VFR ELSEWHERE.
MON-WED...VFR TO MVFR. CHC OF PCPN TUE-WED.

.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
PAZ004-005.

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...DANGELO/TYBURSKI
AVIATION...GARTNER/MARTIN

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA

NWS SIOUX FALLS SD

930 PM CST SUN NOV 25 2012

.DISCUSSION.../ISSUED AT 930 PM CST/
FORECAST FOR TONIGHT LOOKS IN PRETTY GOOD SHAPE. LOW LEVEL DRY AIR
HAS KEPT THE LIGHT SNOW ASSOCIATED WITH THE MID LEVEL FRONT TO THE
SOUTHWEST OF OUR CWA. THINK THIS WILL REMAIN THE CASE THROUGH THE
NIGHT...WITH JUST SOME FLURRIES POSSIBLE ALONG AND SOUTH OF THE
MISSOURI RIVER. LOW LEVEL FRONT AND PUSH OF COLDER AIR WILL MOVE
ACROSS THE CWA TONIGHT FROM NORTH TO SOUTH. THINKING WE SEE ANOTHER
BATCH OF STRATUS BEHIND THIS FRONT AT LEAST ACROSS THE NORTHEAST
HALF OF THE CWA. THIS SHOULD KEEP TEMPERATURES FROM DROPPING AS MUCH
AS THEY COULD...BUT STILL EXPECTING LOWS FROM THE LOWER TEENS NORTH
TO LOWER 20S SOUTH. STRATUS MAY LINGER INTO MID MORNING...BEFORE
GIVING WAY TO INCREASING SUN TOMORROW...AS MID AND HIGH CLOUDS ALSO
EXIT THE REGION. /CHENARD

.PREVIOUS DISCUSSION.../ISSUED AT 250 PM CST/
MAIN CHALLENGES TONIGHT LIE IN THE AMOUNT OF CLOUD COVER ACROSS THE
AREA...WITH POTENTIAL IMPACTS ON OVERNIGHT LOWS...AND PRECIPITATION
POTENTIAL IN OUR FAR SOUTHWEST. STRATUS WHICH RESIDED ACROSS THE
AREA EARLIER IN THE DAY HAS NOW DISSIPATED OVER THE ENTIRE CWA.
TEMPERATURES HAVE BEEN A BIT TRICKY WITH BREAKS IN THE CLOUDS
ALLOWING FOR A RELATIVELY RAPID RISE IN TEMPERATURES IN CLEAR
AREAS...THEN TEMPERED BACK OR FALLING SLIGHTLY WITH THE RETURN OF
CLOUDS. CLOUDS ARE BEGINNING TO FILL BACK IN WITH TWO AREAS
CONVERGING FROM THE NORTH AND SOUTH...MID CLOUDS ACROSS THE SOUTH
AND LOWER CLOUDS DROPPING SOUTHWARD OUT OF NORTH DAKOTA AND NORTHERN
SOUTH DAKOTA AT THIS TIME. MAY SEE A RETURN OF STRATUS...AT LEAST IN
OUR EAST TONIGHT...WITH GFS/NAM/AND RAP INDICATING THE PREVIOUSLY
MENTIONED STRATUS TO OUR NORTH ADVECTING SOUTHWARD ON A
NORTH/NORTHWESTERLY LOW LEVEL FLOW.

WHILE WE DID HAVE A COOLER DAY ACROSS THE AREA...EVEN COLDER AIR IS
POISED TO DRAIN INTO THE REGION TONIGHT BEHIND A SHORTWAVE TRACKING
THROUGH THE UPPER MIDWEST AND INTO THE GREAT LAKES REGION OVERNIGHT.
WITH THIS...WE WILL SEE MUCH COLDER LOWS TONIGHT...MADE SOMEWHAT
CHALLENGING BY WHEN/WHERE THERE IS CLOUD COVER TONIGHT. WITH WINDS
REMAINING FAIRLY LIGHT OVERNIGHT...IF ANY CLEARING TAKES PLACE
READINGS WILL DROP RATHER QUICKLY. AT THIS POINT...HAVE LOWS IN THE
LOWER TEENS NORTH...WHERE COLD AIR ADVECTION WILL BE MOST REALIZED
OVERNIGHT...TO THE LOWER 20S THROUGH OUR FAR SOUTH.

AS FAR AS PRECIPITATION POTENTIAL...RADAR IMAGES HAVE SHOWN RETURNS
THROUGH MUCH OF THE DAY FROM SOUTHWESTERN SOUTH DAKOTA INTO
NORTHEASTERN NEBRASKA...INCLUDING OUR FAR SOUTHERN MISSOURI RIVER
CORRIDOR ZONES...IN THE VICINITY OF A MIDLEVEL BOUNDARY...THOUGH
WITH LOW LEVEL DRY AIR IN PLACE THE ONLY LOCALES REPORTING
PRECIPITATION THUS FAR HAVE BEEN OVER SOUTHWESTERN SOUTH DAKOTA AND
NORTH CENTRAL NEBRASKA. KEPT ONLY SMALL CHANCE POPS IN OUR
SOUTHWESTERN AREAS AS A SHORTWAVE TRACKS OUT OF THE NORTHERN ROCKIES
OVERNIGHT...THOUGH STILL APPEARS THAT THE MIDLEVEL BOUNDARY WILL
BEGIN TO WEAKEN AND SAG SOUTHWARD LATE BEFORE THE BETTER UPPER LEVEL
SUPPORT MOVES INTO THE REGION.

THE COLDEST THERMAL PROFILES WILL BE DRAPED ACROSS OUR AREA ON
MONDAY...ESPECIALLY IN OUR NORTHEAST...WITH HIGHS RANGING FROM THE
LOWER 20S OVER THAT AREA TO THE LOWER 30S THROUGH THE MISSOURI
RIVER CORRIDOR. ALL MODEL RH TIME SECTIONS SHOWING CLOUDS EVENTUALLY
CLEARING OUT BY MONDAY AFTERNOON...SO SHOULD SEE MOSTLY SUNNY SKIES
BY THAT TIME OVER AT LEAST THE NORTHERN TWO THIRDS OF OUR CWA. /JM

SPLIT JET ACROSS THE US IS EXPECTED TO FOCUS MAINLY ON THE NORTHERN
BRANCH THROUGHOUT THE WEEK AS THE SOUTHERN BRANCH WEAKENS.
THROUGHOUT THE WEEK...THE NORTHERN BRANCH OF THE JET IS EXPECTED TO
BUCKLE NORTH AS NORTHWEST FLOW TRANSITIONS TO ZONAL FLOW IN THE MID
LEVELS OF THE ATMOSPHERE. THIS WOULD TYPICALLY RESULT IN A WARMING
TREND...HOWEVER...CLOUD COVER WILL LIKELY HAVE THE MAIN EFFECT ON
TEMPERATURES.

A WEAK COLD FRONT WILL MOVE THROUGH THE AREA ON TUESDAY AFTERNOON.
BOUNDARY IS MAINLY FOCUSED IN THE LOWER LEVELS WITH LITTLE IN THE
WAY OF COLD AIR BEHIND THE FRONT. STILL APPEARS AS THOUGH SOME
STRATUS MAY WORK INTO THE FORECAST AREA FROM THE NORTH TUESDAY NIGHT
LIMITING RADIATIONAL IMPACT. WITH WEAK FLOW ACROSS THE AREA ON
WEDNESDAY...WILL BE A STRUGGLE FOR AREAS IN THE EAST TO WARM IF
STATUS IS ABLE TO PENETRATE INTO THE FORECAST AREA. FOR NOW...HAVE
COOLED FORECAST HIGHS IN SOUTHWEST MINNESOTA...CLOSE TO 925 HPA
ISOTHERMAL...THOUGH MAY HAVE TO EXPAND THE COOLING AS CONFIDENCE IN
THE STRATUS INCREASES.

WEDNESDAY NIGHT A WEAK BOUNDARY APPROACHES FROM THE WEST WITH NO
UPPER LEVEL SUPPORT. MODELS HINT THAT THE BOUNDARY MAY STALL ACROSS
WESTERN PORTIONS OF THE FORECAST AREA...LEAVING THE EAST IN MILD
SOUTHERLY FLOW. THE EAST MAY STILL BE DEALING WITH STRATUS
CONCERNS...SO HAVE SQUASHED DIURNAL RANGE A BIT THURSDAY INTO
FRIDAY. OVERALL...HAVE A GRADUAL WARMING TREND AS 925 HPA TEMPS
WARM FROM 5 TOWARDS 10 DEGREES C.

MODELS SHOW ANOTHER COLD FRONT MOVING THROUGH THE AREA LATE ON
SATURDAY...THOUGH THE STRENGTH OF THE FRONT IS UNDER DEBATE. RIGHT
NOW...THE GFS IS MUCH WEAKER WITH THE FRONT THAN THE ECMWF. WHILE
THE MID LEVEL PATTERN IS MORE ACTIVE...MOISTURE STILL APPEARS TO BE
QUITE LIMITED SO KEPT DRY FORECAST THROUGH NEXT WEEKEND.

STILL APPEARS AS THOUGH A MORE SIZABLE SYSTEM WILL WORK THROUGH THE
NORTHERN PLAINS EARLY THE FOLLOWING WEEK...THOUGH MODELS HAVE BEEN
TRENDING NORTH OF THE FORECAST AREA WITH THE MIDLEVEL WAVE.
&&

.AVIATION.../FOR THE 00Z TAF ISSUANCE/
OCCASIONAL MVFR CEILINGS NORTH OF A MHE-SPW LINE THROUGH 10Z AND
THEN VFR. VFR CONDITIONS TO THE SOUTH WITH A CHANCE OF LIGHT SNOW
SOUTH OF A 9V9-YKN LINE THROUGH 12Z MONDAY.

.FSD WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
MN...NONE.
NE...NONE.
SD...NONE.

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA

NWS SIOUX FALLS SD

537 PM CST SUN NOV 25 2012

.DISCUSSION.../ISSUED AT 250 PM CST/
MAIN CHALLENGES TONIGHT LIE IN THE AMOUNT OF CLOUD COVER ACROSS THE
AREA...WITH POTENTIAL IMPACTS ON OVERNIGHT LOWS...AND PRECIPITATION
POTENTIAL IN OUR FAR SOUTHWEST. STRATUS WHICH RESIDED ACROSS THE
AREA EARLIER IN THE DAY HAS NOW DISSIPATED OVER THE ENTIRE CWA.
TEMPERATURES HAVE BEEN A BIT TRICKY WITH BREAKS IN THE CLOUDS
ALLOWING FOR A RELATIVELY RAPID RISE IN TEMPERATURES IN CLEAR
AREAS...THEN TEMPERED BACK OR FALLING SLIGHTLY WITH THE RETURN OF
CLOUDS. CLOUDS ARE BEGINNING TO FILL BACK IN WITH TWO AREAS
CONVERGING FROM THE NORTH AND SOUTH...MID CLOUDS ACROSS THE SOUTH
AND LOWER CLOUDS DROPPING SOUTHWARD OUT OF NORTH DAKOTA AND NORTHERN
SOUTH DAKOTA AT THIS TIME. MAY SEE A RETURN OF STRATUS...AT LEAST IN
OUR EAST TONIGHT...WITH GFS/NAM/AND RAP INDICATING THE PREVIOUSLY
MENTIONED STRATUS TO OUR NORTH ADVECTING SOUTHWARD ON A
NORTH/NORTHWESTERLY LOW LEVEL FLOW.

STILL APPEARS AS THOUGH A MORE SIZABLE SYSTEM WILL WORK THROUGH THE
NORTHERN PLAINS EARLY THE FOLLOWING WEEK...THOUGH MODELS HAVE BEEN
TRENDING NORTH OF THE FORECAST AREA WITH THE MIDLEVEL WAVE.
&&

.FSD WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
MN...NONE.
NE...NONE.
SD...NONE.

AREA FORECAST DISCUSSION

NWS NEW YORK NY

100 AM EST MON NOV 26 2012

.SYNOPSIS...
HIGH PRESSURE PASSES TO THE SOUTH THROUGH MONDAY...WHILE DEEPENING
LOW PRESSURE LIFTS NORTH ACROSS THE CANADIAN MARITIMES. ANOTHER
WEAKER LOW WILL PASS WELL SOUTH OF THE AREA TUESDAY INTO TUESDAY
NIGHT...FOLLOWED BY HIGH PRESSURE FOR THE SECOND HALF OF THE
WEEK.

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
CLOUDS HAVE BUILT BACK IN FROM THE NORTHWEST OVER THE LAST FEW
HOURS...IN TURN SIGNIFICANTLY SLOWING RADIATIONAL COOLING ACROSS A
LARGE PORTION OF THE AREA. THEREFORE...HAVE SLOWED THE RATE OF
COOLING OVERNIGHT AND BUMPED UP THE LOWS A FEW DEGREES. MAINLY
JUST THE INTERIOR SECTIONS SHOULD SEE TEMPS DIP INTO THE 20S.

THE 03Z RAP HAS A FAIRLY GOOD HANDLE ON THE CLOUD COVER AND KEEPS
IT IN PLACE UNTIL AROUND 09Z OR SO. BASED ON CURRENT TRENDS...THIS
SEEMS PLAUSIBLE...SO HAVE ADJUSTED THE SKY FORECAST TO REFLECT
THIS THINKING. REST OF FORECAST IS ON TRACK.

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
A NEARLY ZONAL FLOW WILL SEND A DIGGING SHORT WAVE FROM THE
NORTHERN PLAINS SOUTHEAST INTO THE MID SECTION OF THE COUNTRY BY
MON NIGHT. MODELS HAVE TRENDED WEAKER AND FLATTER WITH THIS WAVE
AS IT WILL AID THE DEVELOPMENT OF SURFACE LOW OVER THE TN VLY.
THIS LOW WILL THEN TRACK NE TO OFF THE MID ATLANTIC COAST ON TUE.

PRIOR TO THAT TIME...A DRY WESTERLY FLOW ON MON WILL ALLOW FOR
PLENTY OF SUN WITH HIGHS REBOUNDING INTO THE UPPER 40S...STILL A
FEW DEGREES BELOW NORMAL. CLOUDS WILL THEN BE ON THE INCREASE MON
NIGHT IN ASSOC WITH THE AFOREMENTIONED LOW. THERE IS A SLIGHT CHC
OF SNOW...POSSIBLY MIXED AT THE COAST DEVELOPING NEAR DAYBREAK.
ANY PCPN WILL BE LIGHT WITH LITTLE OR NO ACCUMULATION. LOWS WILL
RANGE FROM THE MID 20S WELL NORTH AND WEST...TO THE LOWER 30S
COAST...AND MID 30S NYC METRO.

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
OPERATIONAL MODELS AND GEFS ARE COMING INTO BETTER AGREEMENT ABOUT
THE COASTAL LOW DEVELOPMENT AT THE BEGINNING OF THE LONG TERM
PERIOD. A FIRST NORTHERN SHORTWAVE DIGS INTO THE MIDWEST MONDAY
NIGHT AND BECOMES THE FOCUS FOR THE LOW DEVELOPMENT. AS IT TRACKS
EAST...A WEAK SURFACE WAVE DEVELOPS NEAR THE DELMARVA REGION AND
PRECIP EXPANDS NORTHWARD. THIS WAVE TRACKS EAST AND A SECOND
NORTHERN SHORTWAVE THEN DIGS INTO THE TENNESSEE VALLEY...HELPING TO
STRENGTHEN THE LOW PRESSURE EAST OF THE 40/70 LAT/LON BENCHMARK.
WITH THESE TWO STREAMS NOT PHASING SOON ENOUGH...IT ALLOWS THE LOW
TO STRENGTHEN FARTHER OFFSHORE TUESDAY NIGHT.

EVEN WITH THE MODELS IN DECENT AGREEMENT...THERE ARE STILL
VARIATIONS IN THE EXACT LOCATION OF THE LOW AND HOW CLOSE IT TRACKS
TO THE COAST. THIS WILL EFFECT THE BOUNDARY LAYER TEMPERATURES...HOW
MUCH PRECIP ACTUALLY MAKES IT OVER LAND AND THE TYPE OF PRECIP THAT
FALLS. THE GFS HAS CONSISTENTLY BEEN A COOLER SOLUTION WITH THE
ECMWF NOW FOLLOWING SUIT. THE NAM HAS A BOUNDARY LAYER A FEW DEGREES
WARMER THAN THE OTHER MODELS...LEAVING A MOSTLY RAIN SOLUTION FOR
THE COASTS/LONG ISLAND. THE KEY HERE IS THE BOUNDARY LAYER
TEMPERATURES BECAUSE MUCH OF THE COLUMN IS COLD ENOUGH TO SUPPORT
SNOW.

AS FOR TYPE AND AMOUNTS OF PRECIP...GFS/GEFS/NAM/CMC HAVE BEEN
SHOWING A CONSISTENTLY DRIER SOLUTION. ECMWF 00Z IS ONE OF THE
WETTER AND SLOWER SOLUTIONS WITH THE 12Z COMING IN JUST SLIGHTLY
DRIER THAN THE 00Z. THEREFORE...HAVE DROPPED QPF AMOUNTS OVERALL FOR
THE SYSTEM AND KEPT MOST QPF ON TUESDAY WITH DRY WEATHER ON
WEDNESDAY AS THE SYSTEM IS MOVING QUICKLY. HIGHER QPF AMOUNTS ARE
EXPECTED ALONG LONG ISLAND/NYC/SOUTHERN CT AS THE LOW STRENGTHENS
OFFSHORE. FOR THE LOWER HUDSON VALLEY/INTERIOR CT AND INTERIOR
PORTIONS OF NE NJ...ALL SNOW IS EXPECTED BUT WITH THE LOW QPF
VALUES...LIKELY WILL ONLY SEE 1-2 INCHES OF SNOW. HIGHER ELEVATIONS
HAVE A CHANCE OF EXPERIENCING SLIGHTLY HIGHER AMOUNTS. FOR LONG
ISLAND/NYC/COASTAL CT...TEMPERATURES ARE GOING TO BE RIGHT ON THE
BORDER OF A RAIN/SNOW MIX OR RAIN EVENT. LOOKS TO START OUT AS A
MIX...TRANSITION TO RAIN DURING THE DAY TUESDAY AND END TUESDAY
NIGHT AS A RAIN/SNOW MIX AGAIN. IF A HEAVIER BAND OF PRECIP SETS UP
OVER THOSE AREAS...COULD SEE A BRIEF PERIOD OF SNOWFALL BUT WILL NOT
ACCUMULATE TO ANY MORE THAN A HALF AN INCH IF THAT OCCURS. THERE IS
STILL UNCERTAINTY IN THE TEMPERATURES BECAUSE OF THE TRACK OF THE
LOW AND SUBSEQUENT FORECASTS MAY MAKE CHANGES ACCORDINGLY.

BEHIND THE COASTAL STORM...WINDS PICK UP WEDNESDAY AND THURSDAY AS
THE LOW DEEPENS WELL OFFSHORE AND THE GRADIENT TIGHTENS BETWEEN IT
AND THE HIGH PRESSURE BUILDING IN FROM THE WEST. THIS LARGE AREA OF
HIGH PRESSURE COVERING MUCH OF THE EAST COAST WILL BUILD IN AT THE
SURFACE AND MOSTLY ZONAL FLOW ALOFT RETURNS AS THE REMAINING UPPER
LOW IN CANADA MOVES AWAY. HIGH TEMPERATURES DURING THE WEEK WILL
REMAIN BELOW NORMAL WITH A BIT OF A WARM UP EXPECTED FOR THE WEEKEND
AHEAD OF AN APPROACHING FRONTAL SYSTEM. LOWS FOR THE WEEK WILL
REMAIN AT OR BELOW FREEZING FOR MOST OF THE AREA WITH LOWS WARMING
UP INTO THE WEEKEND.

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
DEEP LOW PRESSURE OVER EASTERN CANADA WILL MOVE SLOWLY NORTH
THROUGH THIS AFTERNOON...WHILE HIGH PRESSURE BUILDS TO THE SOUTH.
ANOTHER HIGH WILL BUILD IN FROM THE WEST LATE IN THE PERIOD AS A
WAVE OF LOW PRESSURE APPROACHES FROM THE SW.

VFR. BKN-OVC060 VFR CIGS LIKELY TO HANG ON UNTIL AT LEAST 10Z.
WESTERLY FLOW WILL CONTINUE WITH WINDS 260-290 TRUE...BACKING TO
280-300 TRUE BY 15Z AND INCREASING TO 10-12 KT WITH GUSTS JUST SHY
OF 20 KT. AFTER 21Z MON WINDS SHOULD DIMINISH AGAIN BELOW 10 KT...
AND THEN BECOME LIGHT AND VARIABLE MON NIGHT.

.OUTLOOK FOR 06Z TUE THROUGH FRI...

.LATE MON NIGHT...VFR.

.TUE...IFR CONDS POSSIBLE IN PRECIPITATION. KSWF/KHPN SHOULD
REMAIN ALL SNOW WITH SOME LIGHT ACCUMULATION ON RUNWAYS...WHILE
OTHER TERMINALS COULD SEE MORNING SNOW CHANGING TO AN AFTERNOON
SNOW/RAIN MIX...THEN CHANGING BACK TO SNOW AT NIGHT...WITH LITTLE
TO NO ACCUMULATION ON RUNWAYS.

.WED...POSSIBLE MVFR CIGS IN THE MORNING. NW FLOW G20KT.

.THU...VFR. WNW FLOW G20KT.

.FRI...VFR.

.MARINE...
WINDS AND SEAS WERE A BIT LOW ON THE OCEAN WATERS...SO MINOR
ADJUSTMENTS UPWARD MADE EARLY THIS MORNING. SCA CONDITIONS
CONTINUE ON THE OCEAN AND EASTERN WATERS THROUGH TONIGHT. SCA FOR
SEAS MAY NEED TO BE EXTENDED ON THE EASTERN OCEAN WATERS FOR A
LITTLE WHILE MON MORNING...BUT WILL WATCH TRENDS THE NEXT FEW
HOURS AND ADDRESS THIS IN THE EARLY MORNING FORECAST PACKAGE.

WINDS AND WAVES WILL REMAIN BELOW SCA CRITERIA AS HIGH PRESSURE
IS OVERHEAD THROUGH TUESDAY AFTERNOON. AS THE LOW PRESSURE
OFFSHORE ON TUESDAY DEEPENS...THE PRESSURE GRADIENT WILL TIGHTEN
AND WINDS AND WAVES WILL PICK BACK UP. WINDS SHOULD BE ABOVE SCA
CRITERIA BY TUESDAY NIGHT/WEDNESDAY MORNING AND WILL LIKELY
CONTINUE THROUGH FRIDAY MORNING. WITH THE CONTINUED WINDS...WAVES
WILL ALSO INCREASE AND COULD BE ABOVE 5FT BY THURSDAY MORNING. DUE
TO THE UNCERTAINTY STILL WITH THE EXACT TRACK AND STRENGTH OF THE
LOW... THE TIMING OF THE STRONGEST WINDS/HIGHEST WAVES MAY VARY
SLIGHTLY

.HYDROLOGY...
LOW PRESSURE AFFECTING THE REGION TUE INTO EARLY WED COULD BRING
UP TO 1/4 INCH LIQUID QPF...WITH THE HIGHEST AMOUNTS ALONG THE
COAST. SOME OF THIS MAY BE IN THE FORM OF SNOW WITH AMOUNTS UP TO
AN INCH.

.TIDES/COASTAL FLOODING...
A FULL MOON IS EXPECTED ON WED. BASED ON THE TRENDS OF TIMING...
TRACK AND INTENSITY OF LOW PRESSURE EXPECTED TO AFFECT THE AREA
TUE INTO EARLY WED...THE PROBABILITY FOR MINOR COASTAL FLOODING
REMAINS LOW FOR VULNERABLE LOW-LYING LOCATIONS.

.EQUIPMENT...
KOKX WSR-88D IS OUT OF SERVICE DUE TO A MAJOR NON STORM RELATED
MECHANICAL FAILURE. OSF RADAR OPERATIONS CENTER TECHS HAVE
ARRIVED TO BEGIN WORK...AND THE RADAR IS EXPECTED TO RETURN TO
SERVICE BY THE FIRST WEEK OF DECEMBER.

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
ANZ330-340-350-353-355.

AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

343 AM EST MON NOV 26 2012

.SHORT TERM...
NO SENSIBLE WX CONCERNS THIS PD. WK SW OVR MT WILL AMPLIFY SEWD THIS
PD AND EFFECTIVELY SHUNT SRN STREAM IMPULSE DOWN ALG THE GULF COAST
AS COLD SFC RIDGE EXPANDS SEWD THROUGH THE OH VALLEY. AS A RESULT
SECONDARY LL CAA SURGE TAKES PLACE TDA AND BROADER SCALE FLW VEERS
MORE NRLY AND IN LIGHT OF CURRENT EXTENSIVE MID CLD SHIELD AND
INCOMING SC DECK SEEPING SWD OUT OF WI/MI XPC A LIMITED DIURNAL.
HWVR CLDS XPCD TO ERODE OUT OVERNIGHT AWAY FM LK MI AND W/SFC RIDGE
BLDG IN PREFER COLDEST TEMP BLENDS W/SIMILAR XPCN FOR TUE.

BENIGN WX THIS PD AS SFC RIDGE BLDS SEWD OUT OF SRN CANADA IN BEHIND
WK SW DEAMPLIFYING EWD THROUGH THE NRN LAKES TDA. AND OTHER THAN
CURRENT PATCH OF MID CLDS THAT EXTENDS WWD INTO ERN IA...XPC CLRG
THIS AFTN IN ASSOCN/W LG SCALE DRY SLOT PROGRESSING SEWD OUT OF MN.
MODEST WAA PUSH AHD OF THIS SYS WILL MAKE FOR QUITE A BIT WARMER
TEMPS COMPARED TO YDA W/GENERAL LOW 40S XPCD.

.LONG TERM...WEDNESDAY THROUGH SUNDAY

MAIN FOCUS THIS PERIOD REMAINS ON WARMING TREND AND LOW CHANCES FOR
LIGHT RAIN SHOWERS FRIDAY INTO THE WEEKEND...

AN UPPER TROUGH WILL DROP SOUTHEAST THROUGH THE NORTHERN GREAT LAKES
TUESDAY NIGHT FORCING A WEAK COLD FRONT THROUGH THE LOCAL AREA EARLY
WEDNESDAY MORNING. BRIEF VEERING OF LOW LEVEL WINDS TO WNW AND
LAKE-8H TEMP DIFFERENTIALS IN THE 13-15C RANGE WILL LIKELY SUPPORT A
DEVELOPING SCATTERED TO BROKEN STRATUM`S DECK NORTH OF HWY 30 ON
WEDNESDAY. DRY PROFILE AND MARGINAL OVER LAKE INSTABILITY SHOULD
MITIGATE SNOW POTENTIAL TO NOTHING MORE THAN A FEW FLURRIES ALONG
AND NORTH OF I-80 IN INDIANA/MICHIGAN.

THE LONGWAVE PATTERN WILL BECOME MORE ZONAL LATE THIS WEEK INTO NEXT
WEEKEND. A SERIES OF LOW AMPLITUDE SHORTWAVE TROUGHS EMANATING
OUT OF A LARGE CLOSED LOW OFF THE WEST COAST WILL PROPAGATE EAST
THROUGH THE NORTHERN TIER OF THE US DAYS 5-7. EACH SYSTEM COULD
BRING SOME LIGHT RAIN SHOWER ACTIVITY TO THE REGION...BEST CHANCES
(15-30%) ACROSS THE NORTHERN HALF OF THE FA FRIDAY/FRIDAY NIGHT AND
AGAIN SATURDAY NIGHT/SUNDAY MORNING PER LATEST MODEL ITERATIONS. AT
THE SFC...GUIDANCE CONTINUES TO HINT AT A WEAK FRONTAL BOUNDARY
DEVELOPING IN WEST TO EAST FASHION OVER OR JUST NORTH OF THE FA
FRIDAY...LIFTING WELL NORTH OF THE LOCAL AREA OVER THE WEEKEND. THIS
WILL ALLOW MUCH WARMER AIR TO ADVECT IN WITH HIGHS LIKELY REACHING
THE UPPER 40S TO MID 50S BY SATURDAY. ECMWF/GFS ALSO CONTINUE TO BE
VERY MOIST IN THE 925-850 MB LAYER WITHIN INCREASING SSW FLOW...
WHICH SUPPORTS GOING MOSTLY CLOUDY TO CLOUDY SKY FCST ALONG WITH
DECREASE IN DIURNAL TEMP RANGES.

.AVIATION...
VFR CONDS TO START W/GRADUAL MOISTENING XPCD AT KSBN INTO THIS
AFTN IN CONJUNCTION W/LL CAA SURGE AND VEERING LL FLW YIELDING AN
INCREASING LK MSTR FLUX. 06Z TIMING OF MVFR CIG DVLPMNT MAY BE A
BIT TOO OPTIMISTIC AS 07Z RUC OUTPUT INDICATES DVLPMNT AS EARLY AS 21Z.
OTHERWISE LWR BOUND VFR RANGE SC CLD DVLPMNT TIMING AT KFWA ON
TARGET.

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR LMZ043-046.

SHORT TERM...T
LONG TERM...STEINWEDEL
AVIATION...T

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

1227 AM EST MON NOV 26 2012

.UPDATE...
ISSUED AT 1010 PM EST SUN NOV 25 2012

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 428 PM EST SUN NOV 25 2012

MAIN FCST CONCERNS ARE LES TRENDS.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 428 PM EST SUN NOV 25 2012

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1225 AM EST MON NOV 26 2012

COLDER AIR MOVING INTO THE UPPER LAKES WILL CONTINUE TO GENERATE
LAKE EFFECT -SHSN THRU TODAY...MAINLY AT KIWD AND KCMX DUE TO WNW/NW
FLOW. AT KCMX...MVFR CONDITIONS SHOULD GENERALLY PREVAIL. BACKING
WINDS THIS EVENING AND THE RESULTING CONVERGENCE ZONE MAY BRING A
PERIOD OF HEAVIER SNOW/IFR CONDITIONS THIS EVENING. AT KIWD...
ENHANCED LOW-LEVEL CONVERGENCE SHOULD LEAD TO OCNL HEAVIER SNOW/IFR
CONDITIONS OVERNIGHT. OTHERWISE...MVFR CONDITIONS SHOULD GENERALLY
PREVAIL. AS WINDS BACK THIS EVENING...CONDITIONS WILL IMPROVE TO VFR
AS LAKE EFFECT SHSN END. AT KSAW...DOWNSLOPE NATURE OF WNW WINDS
SHOULD LEAD TO GENERALLY VFR CONDITIONS WITH FLURRIES/-SHSN AT
TIMES.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 428 PM EST SUN NOV 25 2012

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THIS EVENING FOR MIZ006-
085.

LAKE EFFECT SNOW ADVISORY UNTIL 5 AM EST TUESDAY FOR MIZ007.

LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST /9 AM CST/ THIS
MORNING FOR MIZ002-003-009-084.

LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

UPDATE...ROLFSON
SHORT TERM...JLB
LONG TERM...KC
AVIATION...ROLFSON
MARINE...JLB/KC

AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

351 AM CST MON NOV 26 2012

.DISCUSSION...WATCHING RADAR TRENDS VERY CLOSELY EARLY THIS MORNING.
RAPID UPDATE MODEL /RAP/ SUGGESTS A TIGHTENING BAND OF
FRONTOGENESIS THIS MORNING FROM NEAR ALLIANCE SOUTHEAST THROUGH
NORTH PLATTE. THIS APPEARS TO BE OCCURRING...BUT MORE ACROSS NORTH
CENTRAL NEBRASKA...WHERE A TIGHTENING BAND OF SNOW IS EVIDENT ON
RADAR...WHICH IS SLOWLY DROPPING SOUTH. THIS IS LIKELY IN RESPONSE
TO A WEAK UPPER LEVEL DISTURBANCE APPROACHING FROM UPSTREAM OVER
WYOMING. THE RAP MODEL SUGGESTS A COUPLE OF INCHES MAY ACCUMULATE
THIS MORNING...AND A CROSS SECTION OF THE RAP SUGGESTS STRONG LIFT
AND SOME INSTABILITY WITHIN THE BAND OF FRONTOGENESIS...SO WILL
MONITOR THIS VERY CAREFULLY FOR ANY DEVELOPMENT OF BANDED SNOW
WHICH COULD OCCUR FOR A TIME.

OTHERWISE A WINTER WEATHER ADVISORY WAS ISSUED LAST NIGHT FOR NORTH
CENTRAL NEBRASKA...WHERE LIGHT TO MODERATE SNOW FELL ALL DAY SUNDAY.
FOUR INCHES OF SNOW HAD ACCUMULATED AT VALENTINE AS OF
MIDNIGHT...AND ANOTHER INCH WAS STILL EXPECTED TO FALL. TRAVEL HAD
SLOWED CONSIDERABLE ON THE MAIN HIGHWAYS...AND WANTED TO GET THE
WORD OUT THAT TRAVEL MAY BE RATHER DIFFICULT DURING THE MORNING
HOURS. SNOWFALL AMOUNTS RANGED FROM 2 TO 5 INCHES ACROSS
NORTH CENTRAL AND NORTHWEST NEBRASKA. FORTUNATELY WIND WAS
LIGHT...SO BLOWING AND DRIFTING WAS NOT A PROBLEM.

ANY SNOW WHICH DEVELOPS THIS MORNING ASSOCIATED WITH THE WEAK
DISTURBANCE MOVING ACROSS SHOULD END EARLY THIS AFTERNOON. MODELS
SUGGEST THAT CLOUD COVER MAY LINGER WELL INTO THE AFTERNOON...AND
HAVE SLOWED DOWN THE CLEARING OF SKIES SOME.

A WARM UP IS STILL EXPECTED TUESDAY AND BEYOND AS BRIEF RIDGING
ALOFT TUESDAY AND WEDNESDAY TRANSITIONS TO NEAR ZONAL FLOW THURSDAY
INTO THE UPCOMING WEEKEND. AFTER THE SNOW TODAY...THE REST OF THE
WEEK LOOKS DRY. ANY ARCTIC AIR WILL REMAIN BOTTLED UP TO OUR NORTH.
HIGHS WILL GENERALLY RANGE FROM THE 40S NORTHERN NEBRASKA...TO THE
50S SOUTHERN NEBRASKA TUESDAY THROUGH THURSDAY. 50S THEN EXPECTED
ALL AREAS FRIDAY INTO THE WEEKEND...WITH A FEW 60 DEGREE READINGS
POSSIBLE ACROSS WESTERN AND SOUTHWEST NEBRASKA.

.AVIATION...EXPECTING MAINLY MVFR CONDITIONS WITH 5SM -SN AT KVTN
THROUGH 12Z.VFR CONDITIONS SHOULD PREVAIL BY 15Z.

SNOWFALL AREA TO DEVELOP SOUTH OVERNIGHT INTO MONDAY MORNING AS
A SHORTWAVE TROUGH MOVES ACROSS EASTERN WYOMING INTO THE NEBRASKA
PANHANDLE. CURRENT VFR CONDITIONS AT KLBF SHOULD TRANSITION TO
MVFR CEILINGS BETWEEN 09Z-12Z WITH P6SM -SN WITH TEMPO OF 2SM -SN
AFTER 12Z. MVFR CONDITIONS COULD PERSIST INTO THE AFTERNOON IF
SYSTEM SLOWS OR IS MORE EXPANSIVE THAN INDICATED BY MODELS.

.LBF WATCHES/WARNINGS/ADVISORIES...WINTER WEATHER ADVISORY UNTIL
NOON CST /11 AM MST/ TODAY FOR
NEZ004>006-008-009-094.

DISCUSSION...TAYLOR
AVIATION...CDC

AREA FORECAST DISCUSSION

NWS BINGHAMTON NY

1253 AM EST MON NOV 26 2012

.NEAR TERM /THROUGH TODAY/...
1030 PM UPDATE...
LAKE BAND CONTINUING TO MOVE NORTH THIS HR AS EVIDENCED ON LATEST
RADAR TRENDS. FURTHER SOUTH...GENERAL LIGHT SYNOPTIC SNOW
CONTINUING TO ALSO FALL ACROSS PORTIONS OF THE FINGER LAKES AND
SUSQUEHANNA VALLEY REGIONS OF CENTRAL NEW YORK. SYNOPTIC ACTIVITY
IS BEING FORCED BY THE COMBINATION OF A WEAK SHEARED OUT SHORTWAVE
TRAVELING OVER THE REGION AND INCREASING WARM AIR ADVECTION IN
ADVANCE OF A WEAK SFC LOW TRAVELING THROUGH SOUTHERN CANADA. THAT
SAID...SYNOPTIC ACTIVITY WILL COME TO AN END IN THE NEXT FEW HRS
WITH ALL ATTENTION REMAINING ON LAKE EFFECT ACTIVITY EAST OF LAKE
ONTARIO.

SEE LITTLE VARIATION IN TEMPERATURES WITH LOWS IN THE UPR 20S
TONIGHT AND HIGHS MONDAY GENERALLY MID 30S.

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
NEXT ITEM TO FOCUS ON WILL BE APPROACHING OPEN WAVE AND WEAK LOW
PRESSURE ON MONDAY NIGHT AND EARLY TUESDAY. THIS LOOKS TO BE A
RATHER MINIMAL EVENT WITH SNOW BREAKING OUT OVER THE LOWER OH/TN
VALLEY REGION DUE TO ISENTROPIC LIFT AHEAD OF THE UPPER WAVE WHICH
THEN LIFTS NORTH INTO MAINLY THE SOUTHERN HALF OF NY AND NEPA.
GFS/NAM IN REASONABLE AGREEMENT THAT WE NEED TO SPEED UP TIMING BY
A GOOD 6 HOURS AS WAA PRECIP DOES TEND TO DEVELOP QUICKER AND
THESE TRENDS SUPPORT THAT. WILL BRING IN LIGHT SNOW BETWEEN 06Z-12Z
TUESDAY...WITH A QUICK HITTING EVENT THAT APPEARS TO BE OUT OF THE
PICTURE BY EARLY AFTERNOON. THIS...ALONG WITH MARGINAL TEMPERATURES
AND MINIMAL LIFT SHOULD BE A LIGHT EVENT WITH NOMINAL ACCUMULATIONS
RANGING FROM A DUSTING TO AN INCH...POSSIBLY 2 INCHES IN THE
MOUNTAINS OF NEPA. THE NORTHERN EXTENT LOOKS TO BE AROUND THE
SOUTHERN TIER OF NY...WITH POSSIBLY A FEW FLURRIES UP NORTH.

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
06Z UPDATE...
LAKE EFFECT SNOW BAND OFF OF LAKE ONTARIO IS MAIN FEATURE OF
INTEREST. WINDS THAT BACKED TO WSW AHEAD OF INCOMING WAVE IN THE
EVENING...WILL BEGIN TO VEER TO W TO EVEN WNW WITHIN A FEW HOURS AS
WAVE PASSES. THIS WILL SEND LAKE ONTARIO BAND ACROSS NY THRUWAY
CORRIDOR INCLUDING KRME AND KSYR...DEGRADING CONDITIONS INTO IFR
AT TIMES THROUGH ABOUT 15Z-18Z...BEFORE BAND BREAKS UP TO MORE
CELLULAR IN NATURE. FOR REMAINDER OF CENTRAL NY TERMINALS...GREAT
LAKES MOISTURE WILL MAINTAIN MVFR OR LOW END VFR CIGS AND
OCCASIONAL FLURRIES BUT WITHOUT SIGNIFICANT VIS DEGRADATION. KAVP
MEANWHILE WILL REMAIN VFR. MOST TERMINALS BY LATE IN THE DAY LOSE
MVFR CIG...HOWEVER...CIGS WILL START LOWERING AGAIN TOWARDS 06Z AS
NEXT SYSTEM APPROACHES FROM THE SOUTHWEST.

OUTLOOK...

TUE...VFR-MVFR WITH CHC IFR AS STORM SYSTEM SLIDES JUST TO THE
SOUTH...ESPECIALLY AVP AND BGM.

WED...VFR-MVFR WITH CHC IFR IN LAKE SNOW SHOWERS...MAINLY KSYR-
KRME.

THU/FRI...VFR.

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
NYZ009.

$$
SYNOPSIS...JAB
NEAR TERM...CMG/JAB
SHORT TERM...JAB
LONG TERM...MSE
AVIATION...MDP

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA

NWS SIOUX FALLS SD

1045 PM CST SUN NOV 25 2012

STILL APPEARS AS THOUGH A MORE SIZABLE SYSTEM WILL WORK THROUGH THE
NORTHERN PLAINS EARLY THE FOLLOWING WEEK...THOUGH MODELS HAVE BEEN
TRENDING NORTH OF THE FORECAST AREA WITH THE MIDLEVEL WAVE.
&&

.AVIATION.../FOR THE 06Z TAF ISSUANCE/
OCCASIONAL MVFR CEILINGS MAINLY NORTH OF A HON-FSD-SPW LINE THROUGH
12Z MONDAY. OTHERWISE VFR CONDITIONS THROUGH 06Z TUESDAY.

.FSD WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
MN...NONE.
NE...NONE.
SD...NONE.

AREA FORECAST DISCUSSION

NWS DENVER/BOULDER CO

327 AM MST MON NOV 26 2012

.SHORT TERM...THE UPPER LEVEL TROF WILL MOVE SKIRT ACROSS NORTHERN
COLORADO TODAY BUT THE BRUNT OF THE PRECIP WILL BE FURTHER NORTH
INTO WYOMING AND NEBRASKA. THE SURFACE COLD FRONT AS MOVED THROUGH
MUCH OF THE NORTHEAST PLAINS AND THE STRATUS AND FOG DECK IS
JUST BEGINNING TO SPREAD SOUTHWEST ACROSS THE FAR NORTHEAST
PLAINS. ANOTHER PATCH OF STRATUS HAS JUST MATERIALIZED FROM
BOULDER TO DENVER AND THIS WILL ALSO EXPAND OVER THE FRONT RANGE
BEFORE DAYBREAK. OVERALL THIS MOISTURE IS VERY SHALLOW AND DON`T
EXPECT MORE THAN JUST A FEW FLURRIES. WE CURRENTLY HAVE FREEZING
DRIZZLE IN THE FORECAST BUT THINK THE MOIST IS LAYER IS EVEN TOO
SHALLOW FOR THAT. MAY BE A BIT OPTIMISTIC ON THE DISSIPATION OF
THE STRATUS TODAY AS LATEST RUC KEEPS CLOUDS IN THROUGH EARLY
AFTERNOON. OVERALL...HAVE LOWER HIGH TEMPS ON THE PLAINS INTO THE
30S AND KEPT CLOUD COVER IN A BIT LONGER. BEST CHANCE OF LIGHT
SNOW WILL TOWARDS THE WYOMING AND NEBRASKA BORDERS AND THAT IS
WHERE THE HIGHEST POPS WILL BE.

CLEARING SKIES BY TONIGHT BUT LOOKS LIKE THE WIND WILL INCREASE
AGAIN OVER THE MOUNTAINS AND EAST SLOPES. POSSIBLY SOME HIGHER
GUSTS UP TO 50 MPH LATE TONIGHT OVER WIND PRONE AND EXPOSED
SLOPES. WILL KEEP WARMER OVERNIGHT LOWS NEAR THE HILLS WITH COLDER
TEMPERATURES IN LOW LYING AREAS OF THE PLAINS.

.LONG TERM...EXPECT AN EXTENDED PERIOD OF DRY AND WARMER THAN
NORMAL TEMPERATURES THROUGH THE LONG TERM PERIOD AS LOW AMPLITUDE
RIDGES AND ZONAL FLOW DOMINATE. THE HIGHER MOUNTAINS WILL
GENERALLY BE BREEZY IN THIS PATTERN AS WELL.

TUESDAYS AND WEDNESDAYS HIGHS WILL BE BACK UP INTO THE MID 50S
AND 60S FOR THE PLAINS AND IN THE 40S FOR THE MOUNTAINS WITH CLEAR
SKIES. WINDS WILL BE A BIT GUSTY COMING OUT OF THE MOUNTAINS AND
FOOTHILLS INTO THE WESTERN URBAN CORRIDOR TUESDAY MORNING...THEN
SHOULD SETTLE DOWN OVER THE LOWER FOOTHILLS AND PLAINS THROUGH
WEDNESDAY. THE HIGHER MOUNTAINS WILL CONTINUE TO HAVE BREEZY
CONDITIONS.

A VERY WEAK SHORTWAVE TROUGH WILL MOVE EAST OVER THE STATE
THURSDAY. MODELS HAVE TRENDED DOWN WITH THE STRENGTH OF THIS
FEATURE OVER THE LAST SEVERAL RUNS...ENOUGH THAT I LOWERED POPS TO
JUST A FEW AREAS OF A SLIGHT CHANCE IN THE NORTHERN MOUNTAINS.
THESE POPS MAY BE ABLE TO BE COMPLETELY TAKEN OUT DEPENDING ON
THE NEXT RUN OR TWO. THE SHORTWAVE IS EXPECTED TO SEND A WEAK COOL
FRONT OVER NORTHEASTERN COLORADO HOWEVER...WITH THE ONLY EFFECT
BEING TO COOL TEMPERATURES A COUPLE DEGREES AT MOST.

FRIDAY AND SATURDAY WILL FEATURE A LOW AMPLITUDE RIDGE WITH A
POSSIBLE WEAK SHORTWAVE TO BRING A SLIGHT CHANCE OF SNOW TO THE
NORTHERN MOUNTAINS WITH DRY AND WARM CONDITIONS REMAINING OVER THE LOWER
ELEVATIONS. ON SUNDAY...MODELS ARE SHOWING A DEEPER TROUGH MOVING
IN OVER THE WEST COAST. DO NOT HAVE CONFIDENCE IN THIS FEATURE
THAT FAR OUT...WILL CONTINUE THE DRY AND WARM FORECAST.

.AVIATION...LOW CLOUDS HAVE QUICKLY DEVELOPED FROM LMO...BJC TO
DEN AND SPREADING EAST AND SOUTH AND SHOULD BE INTO APA AROUND
11Z. WILL LIKELY BE MORE PESSIMISTIC ABOUT THE CLEARING A FEW
HOURS TODAY AND REFLECT THIS IN NEXT 12Z TAF ISSUANCE. THERE MAY
BE A FEW FLURRIES THIS AM BUT THE MOIST AIRMASS IS SO SHALLOW
DOUBT THERE WILL BE ANY ACCUMULATION. SURFACE WINDS WILL BE FROM
THE NORTH AND NORTHEAST THIS AM THEN SHIFTING EAST AND SOUTHEAST
THIS AFTERNOON.

.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...ENTREKIN
LONG TERM....KRIEDERMAN
AVIATION...ENTREKIN

AREA FORECAST DISCUSSION

NWS GRAND JUNCTION CO

326 AM MST MON NOV 26 2012

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 326 AM MST MON NOV 26 2012

HIGH CLOUDINESS ACROSS SE UT/SW CO EARLY THIS MORNING AND ASSOCIATED
WITH THE REMAINS OF A SHEARED SHORTWAVE WILL CONTINUE TO THIN AND
SHOULD BE SOUTH OF OUR AREA BY ABOUT SUNRISE. SATELLITE REVEALED LOW
CLOUDS CREEPING SOUTHWARD THROUGH SOUTH-CENTRAL WY IN COLD ADVECTION
AND WEAK UPSLOPE. THE NAM12...AND RUC13 TO SOME EXTENT... SHOW THIS
COLD ADVECTION PUSHING INTO EXTREME NW CO BEFORE FADING AFTER
MID-MORNING AS A SHORTWAVE CURRENTLY NEAR YELLOWSTONE MOVES ACROSS
NE WY AND INTO THE PLAINS BY AFTERNOON. LOW CLOUDS HAVE RETURNED TO
MT WERNER /K3MW/ ABOVE STEAMBOAT AS OF 10Z...THOUGH ANY PRECIP OVER
THE ELKHEADS/PARK RANGES FROM THESE CLOUDS EARLY THIS MORNING
WILL BE NEGLIGIBLE. HAVE ADDED SOME CLOUDINESS TO THE SKY GRIDS
FOR THE NRN CO MTNS TO ACCOUNT FOR THIS...AND TO A LESSER EXTENT
ALONG THE NORTH SLOPE OF THE ERN UINTA MTNS AS THE SHALLOW
NORTHERLY FLOW ARRIVES. HOWEVER...WITH DRYING WESTERLY FLOW ALOFT
AT 700 MB IN THE MODELS...DO NOT EXPECT THESE CLOUDS TO LAST MUCH
PAST MID-MORNING.

SUNNY SKIES ARE EXPECTED ACROSS THE ENTIRE FORECAST AREA THIS
AFTERNOON. TEMPS WILL BE A BIT COOLER THAN YESTERDAY ESPECIALLY
ACROSS THE NORTH. AN UPPER RIDGE PUMPING UP ALONG THE WEST THIS
MORNING PUSHES INLAND TONIGHT AND REACHES UT/WRN CO ON TUE FOR SUNNY
AND STABLE CONDITIONS TOMORROW AS TEMPS BEGIN TO REBOUND.

.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 326 AM MST MON NOV 26 2012

WARM RIDGE OVER THE INTERMOUNTAIN WEST DOMINATES TUESDAY NIGHT AND
WEDNESDAY...BUT BEGINS TO TAKE PUNCHES AS EARLY AS WEDNESDAY
NIGHT. DEEP POLAR VORTEX WILL BE COVERING A SOLID CHUNCK OF THE
ERN PACIFIC WITH POTENT SHORT WAVES SLAMMING INTO THE WEST
COAST...THIS DOES NOT DO TOO MUCH FOR THE CENTRAL ROCKIES AS SHORT
WAVE ENERGY WILL BE ROTATING TOWARD THE NRN ROCKIES. BUT EACH
PASSING SHORT WAVE WILL BE FLATTENING THE LONG WAVE RIDGE.

THE FIRST SHORT WAVE (OR VORTICITY LOBE ROTATING AROUND POLAR
VORTEX) CROSSES THE FORECAST AREA WEDNESDAY NIGHT. DYNAMICAL FORCING
IS OVER THE NRN ROCKIES...BUT THERE IS SOME MOISTURE ADVECTION AND
POTENTIAL VORTICITY THAT QUICKLY SWEEPS ACROSS WRN COLORADO. THE
SREF AND NAM12 SHOWS SPOTTY LIGHT QPF OVER THE MOUNTAIN TOPS...BUT
GFS AND ECMWF KEEP THINGS DRY. ALTHOUGH CONFIDENCE IS LOW...WILL
HEDGE OUR BETS AND EXPECT SOME FLURRIES OVER THE HIGH COUNTRY WITH
THIS PASSING SHORT WAVE.

THE NEXT CHANCE FOR ANY MOUNTAIN SNOW WILL BE FRIDAY NIGHT...AT
LEAST THE ECMWF SHOWS BETTER STRUCTURE WITH PROGRESSIVE SHORT WAVE
WITH THE TAIL END BRUSHING THE NRN MOUNTAINS. THE GFS SHOWS THE
MOISTURE PLUME AIMED AT THE NRN ROCKIES AND NW WYOMING...MISSING
WRN COLORADO COMPLETELY. BOTH SOLUTIONS ARE PLAUSIBLE AND THE
CONSENSUS MODEL BLEND ADVERTISES LOW POPS...A REASONABLE COMPROMISE FOR
RIGHT NOW.

SATURDAY AND SUNDAY...SUBSTANTIAL MOISTURE WITH THE PACIFIC WAVE
TRAIN POINTED AT THE NRN INTERMOUNTAIN REGION. THE NRN PART OF THE
FORECAST AREA IS ON THE EXTREME SRN FRINGE OF THIS ACTIVITY AND
MOST LIKELY THERE IS NOT SUFFICIENT DYNAMICAL FORCING FOR MUCH IF
ANY PCPN. BUT EXPECT A FEW CLOUDS ACROSS THE NORTH...AND GRADIENT
FLOW WILL BE STRONG ENOUGH FOR SOME AFTERNOON BREEZES ACROSS THE
NORTH. THE SYNOPTIC PATTERN SCREAMS MILD WEATHER THIS WEEKEND...SO
MUCH SO THAT THE GFSX MOS GUIDANCE SHOW NEAR RECORD HIGH
TEMPERATURES ON SUNDAY. HOW WARM?...HOW ABOUT LOWER 50S ACROSS THE
UPPER YAMPA AND UPPER GUNNISON RIVER VALLEYS OR LOWER 60S IN THE
DESERT VALLEYS OF SERN UTAH. WHEN DOES DECEMBER ARRIVE?

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 326 AM MST MON NOV 26 2012

LOCAL CIGS BKN010 OVER KSBS WITH MOUNTAIN TOPS PARTIALLY OBSCURED
UNTIL 16Z...OTHERWISE VFR DOMINATES FOR EASTERN UTAH AND WESTERN COLORADO.

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

SHORT TERM...JAD
LONG TERM...PF
AVIATION...PF

AREA FORECAST DISCUSSION...CORRECTION

NWS NORTHERN INDIANA

950 AM EST MON NOV 26 2012

.LONG TERM...WEDNESDAY THROUGH SUNDAY

MAIN FOCUS THIS PERIOD REMAINS ON WARMING TREND AND LOW CHANCES FOR
LIGHT RAIN SHOWERS FRIDAY INTO THE WEEKEND...

AN UPPER TROUGH WILL DROP SOUTHEAST THROUGH THE NORTHERN GREAT LAKES
TUESDAY NIGHT FORCING A WEAK COLD FRONT THROUGH THE LOCAL AREA EARLY
WEDNESDAY MORNING. BRIEF VEERING OF LOW LEVEL WINDS TO WNW AND
LAKE-8H TEMP DIFFERENTIALS IN THE 13-15C RANGE WILL LIKELY SUPPORT A
DEVELOPING SCATTERED/BROKEN STRATOCU DECK NORTH OF HWY 30 ON
WEDNESDAY. DRY PROFILE AND MARGINAL OVER LAKE INSTABILITY SHOULD
MITIGATE SNOW POTENTIAL TO NOTHING MORE THAN A FEW FLURRIES ALONG
AND NORTH OF I-80 IN INDIANA/MICHIGAN.

.AVIATION...
VFR CONDS TO START W/GRADUAL MOISTENING XPCD AT KSBN INTO THIS
AFTN IN CONJUNCTION W/LL CAA SURGE AND VEERING LL FLW YIELDING AN
INCREASING LK MSTR FLUX. 06Z TIMING OF MVFR CIG DVLPMNT MAY BE A BIT
TOO OPTIMISTIC AS 07Z RUC OUTPUT INDICATES DVLPMNT AS EARLY AS 21Z.
OTHERWISE LWR BOUND VFR RANGE SC CLD DVLPMNT TIMING AT KFWA ON
TARGET.

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.

SHORT TERM...T
LONG TERM...STEINWEDEL
AVIATION...T

AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

1048 AM EST MON NOV 26 2012

.SYNOPSIS...
A BROAD AREA OF HIGH PRESSURE WILL ALLOW FOR A DRY START TO THE
WEEK. A WEAK SURFACE LOW WILL MOVE FROM GULF STATES INTO THE
MID-ATLANTIC TONIGHT INTO TUESDAY...WITH SOME ACCUMULATING SNOW
SOUTHEAST OF PITTSBURGH FOR THE COMMUTE TUESDAY MORNING. HIGH
PRESSURE BUILDING IN FROM THE WEST WILL THEN ALLOW FOR A MOSTLY DRY
REMAINDER OF THE WEEK.

.NEAR TERM /THROUGH TUESDAY/...
15Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO INCREASE
POPS AND SNOW ACCUMULATION AMOUNTS FOR THE RIDGES OF WV/MD.

THE LATEST RAP MID-LEVEL ANALYSIS INDICATES THE UPPER OHIO VALLEY IN
A ZONAL FLOW. A WEAK ELONGATED VORT LOBE IS SLIDING ACROSS THE
SOUTHERN GREAT LAKES. WITH THE WEAK NATURE OF THIS FEATURE...THERE
ARE ONLY MID DECK CLOUDS IN ITS ASSOCIATION. AT THE
SURFACE...LOCALLY THE REGION IS UNDER A BROAD AREA OF HIGH PRESSURE
BETWEEN HIGHS CENTERED ACROSS THE NORTHERN PLAINS AND THE SOUTHEAST.
UPSTREAM...A 1010MB LOW IS DEVELOPING ACROSS TEXAS. A FRONTAL
BOUNDARY EXTENDS NORTHEAST OF THIS FEATURE INTO KY/TN.

WEAK HIGH PRESSURE WILL REMAIN IN CONTROL TODAY WITH CLOUD COVERAGE
LIMITED TO SOME MID DECK AS THE AFOREMENTIONED H5 VORT SLIDES
NORTHEAST OF THE AREA. FOR TEMPS...RECENT TRENDS...ABUNDANT SUNSHINE
THIS MORNING...ALONG WITH LAMP GUIDANCE HAVE LED TO TEMPS BEING
ADJUSTED UP A DEGREE ACROSS THE AREA AND 2-3 DEGREES SOUTH OF I-70.
HIGHS TODAY WILL RANGE FROM THE UPPER 30S NORTH OF I-80 TO THE UPPER
40S ACROSS THE LOWLANDS SOUTH OF I-70.

TONIGHT INTO TUESDAY...THE SURFACE LOW ACROSS TEXAS WILL TRACK
ACROSS THE GULF STATES INTO THE SOUTHERN APPALACHIANS BY 12Z TUESDAY
AND QUICKLY LIFT INTO THE MID-ATLANTIC BY 18Z. 700MB OMEGA SUPPORTS
FORCING MOVING INTO NORTH-CENTRAL WV AND THE SOUTHEAST RIDGES BY 06Z
WITH THE WEAK INVERTED TROUGH ASSOCIATED WITH THE LOW AND
OVERRUNNING AHEAD OF THE LOW. FORCING APPEARS SUFFICIENT FOR AROUND
0.25-0.35 QPF SOUTHEAST OF PITTSBURGH WITH THIS SYSTEM BETWEEN
AROUND 03Z AND 15Z TUESDAY. MODEL THICKNESSES AND SOUNDINGS SUPPORT
THAT THERMAL PROFILE WILL BE COLD ENOUGH FOR PRECIP TO BE ALL SNOW
WITH THIS SYSTEM. WITH THIS IN MIND...BELIEVE SLIGHT ELEVATION
ENHANCEMENT ALONG WITH 10:1-12:1 SNOW-TO-LIQUID RATIOS WILL
CONTRIBUTE TO MAKE THIS AN ADVISORY SNOWFALL EVENT. IN
ADDITION...THE TIMING OF THIS EVENT...AROUND THE MORNING
COMMUTE...WILL INCREASE THE IMPACTS OF THIS SNOWFALL.

FOR SNOW AMOUNTS...FORECAST IS ON THE HIGH END OF GUIDANCE...TAKING
INTO ACCOUNT THE BETTER RESOLUTION OF THE 12KM NAM AND HOW ITS
RESOLVING ENHANCED PRECIP ACROSS THE RIDGES. WITH THAT IN
MIND...ANTICIPATE 2 TO 5 INCHES ACROSS PRESTON...TUCKER...AND
GARRETT COUNTIES WITH THE HIGHEST AMOUNTS ALONG THE HIGHEST RIDGES.
GENERALLY 1 TO 2 INCHES OF SNOW IS FORECAST FOR A TIER OF COUNTIES
TO THE WEST...WHICH WOULD BE A SUFFICIENT AMOUNT OF SNOW TO ALSO
IMPACT THE MORNING COMMUTE...ALBEIT WITH SUB-ADVISORY LEVELS.
OTHERWISE...ACROSS THE PITTSBURGH METRO AND TO THE NORTH AND
WEST...EXPECT LITTLE OR NO ACCUMULATION.

PRECIP WITH THIS SYSTEM LOOKS TO SHIFT EAST OF THE AREA BY 18Z
TUESDAY WITH A DRY REMAINDER OF THE DAY AS HIGH PRESSURE BEGINS TO
BUILD IN FROM THE WEST. FOR TEMPS...LAMP GUIDANCE SEEMS REASONABLE
SOUTHEAST OF PITTSBURGH WITH LOWS IN THE UPPER 20S TO LOWER 30S.
FURTHER NORTH...WENT A FEW DEGREES BELOW GUIDANCE FOR LOWS IN THE
MID 20S. CLOUD COVERAGE WILL CONTRIBUTE TO LIMIT TEMPS FOR HIGHS
ON TUESDAY...GENERALLY IN THE MID TO UPPER 30S ACROSS THE AREA.

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD INTO THE UPPER OHIO VALLEY WITH A DRY AND
COLD TUESDAY NIGHT EXPECTED.

A WEAK UPPER LEVEL DISTURBANCE WILL MOVE ACROSS ONTARIO AND THE
EASTERN GREAT LAKES ON WEDNESDAY. SYNOPTIC MOISTURE WILL MAKE ITS
WAY INTO THE NORTHERN COUNTIES...BUT THIS MAY ONLY PROVIDE CLOUDS
AND NO PRECIPITATION. IT REMAINS TO BE SEEN WHETHER WINDS WILL ALIGN
TO PROVIDE LAKE MOISTURE BEFORE THE SHORTWAVE PUSHES EAST OF THE
REGION. WILL PROBABLY JUST KEEP SLIGHT CHANCE POPS FOR NOW.

NOT MUCH IMPROVEMENT WITH TEMPERATURES WEDNESDAY WITH TEMPS ABOUT
5-10 DEGREES BELOW NORMAL THROUGH THE PERIOD.

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A LARGE SURFACE HIGH WILL BRING CHILLY CONDITIONS MID WEEK. THEN
BY LATE WEEK THERE WILL BE A RETURN OF SOUTHERLY SURFACE WINDS ON
THE BACKSIDE OF HIGH PRESSURE WILL TAKE TEMPERATURES BACK TO
NORMAL. HIGHS WILL PUSH BACK UP INTO THE UPPER 40S AND LOWER 50S
TOWARD THE END OF THE PERIOD. DRY CONDITIONS THROUGH SATURDAY
NIGHT..THEN A CHANCE OF SHOWERS AHEAD OF NEXT SYSTEM ON SUNDAY IN
WEST.

.AVIATION /16Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL KEEP VFR CONDITIONS THROUGH THIS EVENING...WITH
THE POSSIBILITY OF MVFR RESTRICTIONS DEVELOPING SOUTH OF
PITTSBURGH LATE TONIGHT AS LIGHT SNOW MOVES INTO THE AREA.

.OUTLOOK.../TUESDAY THROUGH FRIDAY/...
SNOW SHOWERS WILL PASS THROUGH THE REGION IN THE SOUTH AND EAST
EARLY TUESDAY MORNING THROUGH LATE AFTERNOON. EXPECT IFR TO MVFR
CONDITIONS IN SOUTHERN AND EASTERN TERMINALS DURING THIS TIME
WHILE THE REMAINING TERMINALS SHOULD REMAIN VFR. VFR CONDITIONS
WILL RETURN FOR THE REST OF THE WEEK ONCE LOW PRESSURE SYSTEM
MOVES EASTWARD.

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

SYNOPSIS...WOODRUM
NEAR TERM...WOODRUM

AREA FORECAST DISCUSSION...UPDATED

NWS MARQUETTE MI

1008 AM EST MON NOV 26 2012

.UPDATE...
ISSUED AT 1007 AM EST MON NOV 26 2012

MAIN QUESTION FOR THE MORNING UPDATE IS THE HANDLING OF THE LAKE
EFFECT SNOW ADVISORY FOR MARQUETTE COUNTY. STRONGER BAND THAT WAS
SETUP OVER BIG BAY THIS MORNING HAS DISSIPATED AS LOW LEVEL WINDS
HAVE SHIFTED MORE OUT OF THE WEST AND AT TIMES SOUTHWEST. THIS HAS
WEAKENED THE ENTIRE BAND...EVEN TOWARDS MUNISING WHERE VISIBILITIES
WERE LESS THAN A HALF MILE BASED OFF WEBCAMS. WITH THIS BAND
DIMINISHING...ATTENTION TURNS TO STRONGER BAND LOCATED ALONG THE
SURFACE TROUGH OVER EASTERN LAKE SUPERIOR...MAINLY FROM THE TIP OF
THE KEWEENAW TO WHITEFISH POINT. WINDS HAVE SHIFTED TO THE NORTH
BEHIND THIS TROUGH AND HAVE BEEN AIDING A SOUTHWARD PUSH OVER THE
LAST COUPLE OF HOURS. QUESTION WITH THIS BAND IS WHERE IT WILL
BECOME FOCUSED LATER THIS AFTERNOON AND INTO TONIGHT. LATEST RUC RUN
AND 00Z NCEP WRF-ARW/NMM FOCUSES IT OVER ALGER AND NORTHERN
SCHOOLCRAFT...WHILE OUR LOCAL 12Z WRF...12Z NAM...AND 06Z NCEP
WRF-ARW/NMM HOLDS IT OVER LUCE COUNTY WITH A WEAKER NORTHERLY PUSH
OVER EASTERN LAKE SUPERIOR. BOTH CASES LIMIT THE WESTWARD EXTENT DUE
TO THE LOWERING INVERSIONS AND DRIER AIR FROM A SURFACE RIDGE MOVING
OVER WESTERN UPPER MICHIGAN THIS AFTERNOON. SINCE THERE IS ALREADY
AN ADVISORY OUT FOR LUCE...WILL KEEP IT AS IS AT THIS POINT...BUT
WILL MONITOR FOR POTENTIAL UPGRADE TO WARNING IF BAND HOLDS UP IN
LUCE COUNTY.

AS FOR MARQUETTE...THINKING OF DROPPING THE ADVISORY SINCE THE MAIN
BAND THAT IT WAS ISSUED FOR HAS DISSIPATED. THERE IS SOME CONCERN
FOR N-S BANDS DEVELOPING NEAR THE TIP OF THE KEWEENAW...BUT THE
GENERAL MORE NORTHWESTERLY FLOW AHEAD OF THE TROUGH SHOULD PUSH IT
EAST OF BIG BAY AND MUCH OF MARQUETTE COUNTY.
&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 431 AM EST MON NOV 26 2012

WNW FLOW ALOFT SEEN ON WV LOOP AND 00Z RAOBS. ONE SHORTWAVE WORKED
THROUGH THE AREA SUNDAY EVENING AND ANOTHER WEAKER WAVE IS POISED
TO MOVE ACROSS LATE THIS MORNING/EARLY AFTN. BASED ON RADAR AND SFC
OBS APPEARS THAT OUTSIDE OF STRONGEST CONVERGENCE ZONE OVER EASTERN
LK SUPERIOR CLOSER TO SFC LOW/TROUGH...AIRMASS IS ONLY CONDITIONALLY
UNSTABLE FOR STRONG LK EFFECT SNOW /LES/ DESPITE AMPLE OVER-WATER
INSTABILITY /SFC-H85 DELTA T/S OVER 20C AND LAKE EQUILIBRIUM LEVELS
OVR 7KFT/. IN THE NEXT FEW HOURS...H85 COLD FRONT OVER NORTHWEST LK
SUPERIOR WILL MAKE ITS WAY ACROSS WESTERN LK SUPERIOR. EXPECT
CYCLONIC WNW-NW FLOW TO AFFECT WESTERN LK SUPERIOR AND INTO WESTERN
CWA RESULTING IN THE WEAKLY ORGANIZED LK EFFECT WHICH IS PRESENT TO
SPIKE IN INTENSITY. ALREADY SEEING SIGNS OF THIS AT KIWD WITH VSBY
BRIEFLY DOWN TO 1 1/4SM AND MODERATE SNOW NOTED PER WEBCAM FROM
IRONWOOD. PERIOD FOR PICKUP IN SNOW LOOKS TO LAST THROUGH THE
MORNING BEFORE INVERSIONS FALL BLO 5KFT AND DRY AIR IN BLYR /SFC
DWPNTS BLO 10F UPSTREAM/ COMBINE TO DECREASE SNOW INTENSITY. SNOW
AMOUNTS FOR THE MORNING OF 3-5 INCHES SEEM LIKELY IN ADVY AREA.
GIVEN POTENTIAL OF HEAVIER SNOW BANDS LINGERING THROUGH
MIDDAY...DELAYED EXPIRATION OF ADVY TIL 18Z.

OVER THE EASTERN CWA...CURRENT LES TRENDS AND VERY CONSISTENT OUTPUT
FROM HIGHER RESOLUTION GUIDANCE LAST DAY OR TWO SUPPORT EXPANSION OF
HEAVY LES FROM MUNISING TO GRAND MARAIS TO PINE STUMP JUNCTION
THROUGH THE DAY. ARRIVAL OF H85 TROUGH SHOULD RESULT IN SFC TROUGH
OVER EASTERN LK SUPERIOR SINKING TOWARD THE SHORELINE THIS MORNING.
NET RESULT IS STRONG AREA OF SFC CONVERGENCE SETTING UP/PERSISTING
OVER SOUTHEAST LK SUPERIOR INTO ALGER/NORTHERN SCHOOLCRAFT COUNTIES
THROUGH THE AFTN. UNLIKE THE WESTERN CWA...CONDITIONS OVER EASTERN
LK SUPERIOR WILL NOT BE NEAR AS HOSTILE TO LES THIS AFTN AS
INVERSION/LAKE EQL REMAINS TOWARD 8KFT/10KFT THROUGH MUCH OF THE
DAY...PLACING BULK OF LES CONVECTIVE LAYER WITHIN DGZ/HIGHER SNOW
RATIOS. CONVERGENCE ALREADY STRONGER IN THIS AREA CURRENTLY SO NO
REASON TO BELIEVE LES WILL NOT INTENSIFY TODAY. CURRENT LES WARNING
LOOKS ON TRACK. EXPECT TOTAL DAYTIME SNOWFALL UP TO 8
INCHES...CENTERED ON MUNISING AND MELSTRAND. ALREADY SEEING
CONVERGENCE BAND OF ENHANCE SNOW SETUP IN THESE AREAS CURRENTLY. DID
THINK ABOUT GOING WITH WARNING FOR LUCE AS WELL...BUT SINCE MAJORITY
OF SNOW EARLY THIS MORNING HAS STAYED MAINLY OFFSHORE...EXPECTED
SNOW TOTALS THROUGH THE DAY SUPPORT KEEPING THE ADVY. UPGRADE COULD
BE POSSIBLE DEPENDING ON LES TRENDS THIS MORNING. FARTHER
SOUTH...THOUGHT ABOUT AN ADVY FOR THE DAY OVER SOUTHERN SCHOOLCRAFT
COUNTY. SOME HIGHER RESOULTION MODELS...ESPECIALLY LOCAL WRF AND
NCEP WRF-ARW INDICATE DOMINANT BAND AROUND MUNISING MAY MAKE IT INTO
GOOD PART OF SOUTHERN SCHOOLCRAFT. AT THIS POINT...LOW-LEVEL
CONVERGENCE IS EXPECTED TO BE SHARP BUT PRETTY FOCUSED INTO MAINLY
ALGER COUNTY...SO DECIDED AGAINST ADVY.

AWAY FROM LES TODAY...COLD AIR ADVECTION THROUGH DAY SHOULD LEAD TO
PRETTY STEADY TEMPS OVER CWA...ESPECIALLY GIVEN FAIRLY RESILIENT
CLOUD COVER. FAR WEST PROBABLY STAYS LOCKED INTO THE TEENS WITH
READINGS FALLING THIS AFTN SLIGHTLY. TEMPS IN THE LOW-MID 20S COVER
IT ELSEWHERE.

NO BIG CHANGE TO PREVIOUS THINKING FOR LES TRENDS TONIGHT. HIGH
PRESSURE NEARING FROM THE PLAINS RESULTS IN SFC-H85 WINDS TO
STEADILY BACK WNW IN THE EVENING AND MORE TO THE WSW OVERNIGHT.
HEADLINES CONTINUE OVER NORTHEAST CWA THROUGH EVENING...WITH A FEW
MORE INCHES OF SNOW LIKELY. AWAY FROM LES...BACKING WINDS SHOULD
ALLOW SKIES TO CLEAR IN THE EVENING WITH POSSIBLY THE COLDEST NIGHT
OF THE LATE FALL ON TAP. EXPECT TEMPS TO DROP QUICKLY INTO THE LOWER
TEENS AND SINGLE DIGITS OVERNIGHT. ANOTHER CLIPPER SYSTEM NEARING IN
WNW FLOW SPREADS A MID CLOUD DECK ACROSS MUCH OF CWA AFTER MIDNIGHT.
TEMPS LIKELY WILL BECOME STEADY BY THAT TIME SO TEMPS TONIGHT WILL
NOT END UP AS COLD AS THEY WOULD BE OTHERWISE WITH SIMILAR SETUP TO
START THE NIGHT. STILL...MAY SEE MIDDLE SINGLE DIGITS IN THE COLDER
SPOTS OF THE INTERIOR CENTRAL IF SKIES STAY CLEAR LONGER.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 431 AM EST MON NOV 26 2012

A SHORTWAVE TROUGH/SFC TROUGH AND ASSOCIATED COLD FRONT WILL MOVE
ACROSS THE CWA FROM LATE TUE AFTERNOON INTO WED NIGHT...WITH DRY SFC
RIDGING MOVING INTO THE WRN CWA BY 18Z WED. LOW LEVEL FLOW WILL
INITIALLY BE FROM THE WSW WITH 850MB TEMPS OF -8C TO -14C FROM W TO
E RESPECTIVELY. LES SHOULD BE SITTING PRIMARILY OVER THE WRN LAKE
AND NRN KEWEENAW PENINSULA...WITH SOME LES OCCASIONALLY DRIFTING OVER
OTHER LAND AREAS OR WRN UPPER MI. LOW LEVEL WINDS TURN MORE WLY BY
00Z WED THEN NW BY 06Z WED AS 850MB TEMPS DROP TO AROUND -15C. BL
MOISTURE DECREASES PRETTY QUICKLY FROM W TO E LATE WED NIGHT INTO
WED AS THE RIDGE MOVES IN...DIMINISHING /OR AT LEAST SIGNIFICANTLY
WEAKENING/ LES. THE ONE PLACE WHERE LES MAY HANG ON ALL DAY WED IS
OVER THE FAR NE U.P. SINCE ANOTHER SHORTWAVE MOVES INTO NE LAKE
SUPERIOR LATE WED INTO WED NIGHT. LOOKS LIKE ALL BUT THE SOUTH
CENTRAL CWA WILL SEE SNOW FROM THE SHORTWAVE/LES...WITH THE TYPICAL
NW WIND SNOWBELTS SEEING THE MOST SNOW. AT THIS POINT...THE HIGHER
TERRAIN OF THE NW CWA LOOKS TO SEE 3-5 INCHES OF SNOW...AND THE ERN
CWA 2-4 INCHES.

NW LOW LEVEL WINDS WILL VEER AROUND TO THE SE BY FRI NIGHT AS A SFC
HIGH PASSES JUST NE OF THE CWA...BUT CONDITIONS WILL NOT BE
FAVORABLE FOR ANY SIGNIFICANT LES WITH THE MORE N/NE WINDS DURING
THE TRANSITION TO SE WINDS.

GENERAL TREND TOWARD WARMER TEMPS LOOKS IN ORDER FOR FRI INTO THE
WEEKEND. MODELS GENERALLY AGREE THAT LOW PRESSURE AT THE SFC WILL
DOMINATE THE NE CONUS INTO THE PLAINS STATES...AND A SHORTWAVE/WAA
REGIME THAT WOULD BRING SNOW TO THE AREA FRI. CONFIDENCE DECREASES
SIGNIFICANTLY SAT AND SUN AS MODEL AGREEMENT DECREASES AND MODEL RUN
TO RUN CONTINUITY IS POOR. USED A CONSENSUS OF GUIDANCE FOR MUCH OF
THIS PERIOD GIVEN THE DECREASED CONFIDENCE IN ANY ONE MODEL.
&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 643 AM EST MON NOV 26 2012

COLDER AIR MOVING INTO THE UPPER LAKES WILL CONTINUE TO GENERATE
LAKE EFFECT -SHSN THRU TODAY...MAINLY AT KIWD AND KCMX DUE TO WNW/NW
FLOW. AT KCMX...IFR TO MVFR CONDITIONS SHOULD PREVAIL TODAY. BACKING
WINDS THIS EVENING AND THE RESULTING CONVERGENCE ZONE MAY BRING A
PERIOD OF HEAVIER SNOW/IFR CONDITIONS THIS EVENING. AT KIWD...
ENHANCED LOW-LEVEL CONVERGENCE SHOULD LEAD TO OCNL HEAVIER SNOW/IFR
CONDITIONS THIS MORNING. OTHERWISE...MVFR CONDITIONS SHOULD
GENERALLY PREVAIL. AS WINDS BACK THIS EVENING...CONDITIONS WILL
IMPROVE TO VFR AS LAKE EFFECT SHSN END. AT KSAW...DOWNSLOPE NATURE
OF WNW WINDS SHOULD LEAD TO GENERALLY VFR CONDITIONS WITH
FLURRIES/-SHSN AT TIMES.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 431 AM EST MON NOV 26 2012

WITH GENERALLY WEAK CLIPPER SYSTEMS BEING THE MAIN WIND PRODUCERS
OVER THE NEXT FEW DAYS...WINDS OF 20 TO 30 KTS WILL BE COMMON BUT NO
GALES ARE EXPECTED.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THIS EVENING FOR MIZ006-
085.

LAKE EFFECT SNOW ADVISORY UNTIL 5 AM EST TUESDAY FOR MIZ007.

LAKE EFFECT SNOW ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
MIZ005.

LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR MIZ002-003-009-084.

LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

UPDATE...SRF
SHORT TERM...JLA
LONG TERM...TITUS
AVIATION...ROLFSON/JLA
MARINE...TITUS

AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

732 AM CST MON NOV 26 2012

.UPDATE...
THE FRONTOGENETICALLY FORCED BAND OF LIGHT TO MODERATES CONTINUES
TO MOVE SOUTH THIS MORNING PROMPTING THE ADDITION OF ANOTHER TIER
OF COUNTIES TO THE WINTER WEATHER ADVISORY. NONE OF THE MODELS
SEEM TO HAVE A GOOD HANDLE ON THE SOUTHWARD PROGRESSION OF THE
SNOW BAND. GIVEN THE TIME OF DAY AND NEBRASKA DEPARTMENT OF ROADS
REPORTS IT LOOKS LIKE THE SNOW BAND COULD PRODUCE HAZARDOUS TRAVEL
FOR A FEW HOURS THIS MORNING ALONG HIGHWAY 92 AND ACROSS AT LEAST
THE NORTHERN HALF OF CUSTER COUNTY.

WHAT REMAINS TO BE DETERMINED IS THE IMPACT ON INTERSTATE 80. ONE
POSITIVE WOULD BE THE EFFECT OF DAYLIGHT AND THE PREVIOUS DAYS
HIGH TEMPERATURES IN THE 50S. THIS COULD CERTAINLY MINIMIZE THE
TRAVEL HAZARD.

.PREV DISCUSSION... /ISSUED 529 AM CST MON NOV 26 2012/

UPDATE...

AVIATION...
IFR IS EXPECTED THROUGH ROUGHLY 16-18Z THIS AM AS THE SNOW AND LOW
CIGS GRADUALLY WEAKEN. NOTE THE SNOW ARRIVAL AT KLBF IS BASED ON
THE CURRENT RADAR TRENDS WHICH COULD CHANGE AT ANY TIME AS AN
UPPER LEVEL KICKER ACROSS NERN WYOMING THIS MORNING APPROACHES
WHICH WOULD CAUSE THE SNOW BAND TO FALL APART. ALSO THE SNOW
ENDING TIME AT KVTN IS ESSENTIALLY A MODEL GUESS AS THE RADAR IS
OVERSHOOTING THE SNOW AT THAT LOCATION SUGGESTING THE SNOW WILL
END AT ANY TIME.

VFR COULD BE WIDESPREAD BY 18Z AND CONTINUE OVERNIGHT AS HIGH
PRESSURE BUILDS INTO THE REGION.

PREV DISCUSSION... /ISSUED 437 AM CST MON NOV 26 2012/

UPDATE...
REPORTS FROM FROM THE NEBRASKA DEPARTMENT OF ROADS AND RADAR
SUGGEST SNOW WILL CONTINUE TO ACCUMULATE ON ROADWAYS THROUGH
AT LEAST SUNRISE. ADDITIONAL COUNTIES HAVE BEEN ADDED TO THE
WINTER WEATHER ADVISORY. TEMPERATURES CONTINUE TO FALL INTO THE
LOWER 20S ACROSS NRN NEBRASKA SUGGESTING A HIGH PROBABILITY OF
ICING ON ROADWAYS WITH ROAD SFCS LIKELY CROSSING THE FREEZING
MARK.

THE FRONTOGENETICALLY FORCED SNOW BAND ACROSS THE SANDHILLS IS
SHOWING SIGNS OF TIGHTENING UP AS VERY COLD 700MB AIR DRIVES SOUTH
AND COLLIDES WITH WARM MID LEVEL TO THE SOUTH NEAR KLBF.

PREV DISCUSSION... /ISSUED 351 AM CST MON NOV 26 2012/

DISCUSSION...WATCHING RADAR TRENDS VERY CLOSELY EARLY THIS MORNING.
RAPID UPDATE MODEL /RAP/ SUGGESTS A TIGHTENING BAND OF
FRONTOGENESIS THIS MORNING FROM NEAR ALLIANCE SOUTHEAST THROUGH
NORTH PLATTE. THIS APPEARS TO BE OCCURRING...BUT MORE ACROSS NORTH
CENTRAL NEBRASKA...WHERE A TIGHTENING BAND OF SNOW IS EVIDENT ON
RADAR...WHICH IS SLOWLY DROPPING SOUTH. THIS IS LIKELY IN RESPONSE
TO A WEAK UPPER LEVEL DISTURBANCE APPROACHING FROM UPSTREAM OVER
WYOMING. THE RAP MODEL SUGGESTS A COUPLE OF INCHES MAY ACCUMULATE
THIS MORNING...AND A CROSS SECTION OF THE RAP SUGGESTS STRONG LIFT
AND SOME INSTABILITY WITHIN THE BAND OF FRONTOGENESIS...SO WILL
MONITOR THIS VERY CAREFULLY FOR ANY DEVELOPMENT OF BANDED SNOW
WHICH COULD OCCUR FOR A TIME.

AVIATION...EXPECTING MAINLY MVFR CONDITIONS WITH 5SM -SN AT KVTN
THROUGH 12Z.VFR CONDITIONS SHOULD PREVAIL BY 15Z.

.LBF WATCHES/WARNINGS/ADVISORIES...WINTER WEATHER ADVISORY UNTIL NOON
CST /11 AM MST/ TODAY FOR NEZ004>006-008>010-023>028-035>038-094.

SHORT TERM/EXTENDED...CDC
AVIATION...CDC

AREA FORECAST DISCUSSION

NWS HASTINGS NE

558 AM CST MON NOV 26 2012

.AVIATION...12Z KGRI TAF...AN APPROACHING DISTURBANCE WILL BRING
MVFR CIGS AND VSBYS TO THE TERMINAL DURING THE MORNING HOURS
TODAY...WITH CIGS EXPECTED TO EVENTUALLY LIFT...AND VFR CONDS TO
RETURN...BY EARLY EVENING. AS OF 11Z...HAVE SEEN SOME IFR CIGS
DEVELOP AT ORD...ASSOCIATED WITH AN APPROACHING UPPER LEVEL
DISTURBANCE. EXPECT CIGS TO ALSO LOWER AT GRI AS THIS SYSTEM SAGS
A BIT FURTHER SOUTH OVER THE NEXT FEW HOURS...WITH THE ATMOSPHERE
SATURATING AND SOME -SN DEVELOPING. EXPECT ANY PRECIP THAT DOES
DEVELOP...AS WELL AS THE LOWER CIGS...TO DIMINISH BY 18Z...WITH
IMPROVING CONDITIONS BY AFTERNOON/EVENING...WITH LITTLE IF ANY
SNOWFALL ACCUMULATION AT THE TERMINAL ITSELF. WINDS WILL
GENERALLY BE OUT OF THE NORTH AT 10-12KTS THROUGH THE AFTERNOON
HOURS...BECOMING LIGHT AND VARIABLE AFTER SUNSET AS AN AREA OF
SURFACE HIGH PRESSURE BUILDS IN ACROSS THE REGION.

.PREV DISCUSSION... /ISSUED 416 AM CST MON NOV 26 2012/

SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT

MAIN THEME: WINTER MAKES A BRIEF APPEARANCE TODAY WITH SOME MINOR
ACCUMULATION N OF I-80...THEN A RAPID RECOVERY IN TEMPS TOMORROW
AND CONTINUED WARMING THRU MID-WEEK.

UPPER-LEVELS: LONGWAVE TROF CONTS TO ORGANIZE OVER THE E PACIFIC...
DOWNSTREAM OF THE BERING SEA BLOCKING HIGH. A RIDGE WAS BUILDING
ALONG THE W COAST. AS MULTIPLE SHORTWAVE TROFS ORBIT AROUND THE
DEVELOPING CUT-OFF LOW /WITHIN THE LONGWAVE TROF/ THE RIDGE WILL
GRADUALLY HEAD E TO THE FRONT RANGE OF THE ROCKIES BY WED NGT.
BOTTOM LINE...NW FLOW THRU TUE NGT THEN BACKING TO W FLOW WED.

AT 09Z A VORT MAX/SHORTWAVE TROF WAS OVER MT/WY AND DROPPING SE. IN
ADVANCE OF THIS VORT MAX A BATCH -SN WAS OCCURRING WITHIN A PULSE OF
QG FORCING/RRQ OF A 120 KT JET ON THE TROPOPAUSE. THE VORT MAX WILL
CONT SE INTO NEB THIS MRNG.

SURFACE: COLD/STRONG ARCTIC HIGH PRES WAS OVER ND WITH NE LOW-LEVEL
FLOW PROVIDING AN UPSLOPE COMPONENT. THIS HIGH WILL EXPAND AND SINK
SWD OVER THE CNTRL PLAINS BY THIS EVNG...THEN INTO THE LOWER MS
VALLEY TUE AND THE TN VALLEY WED.

00Z RAOBS SHOW LOTS OF DRY AIR TO OVERCOME. SOME OF THE LIFT WILL GO
TOWARD SATURATION WHICH COULD DELAY THE START TIME. USED RAP/NAM
925-850 MB RH OF 90% TO GUIDE OUR POPS AS THAT ISOHUME LINED UP
FAIRLY WELL WITH OBSERVED -SN.

AFTER A FEW FLURRIES AROUND 06Z...STEADY -SN BEGAN AT ORD AT 08Z.

EXPECTATION IS THAT BATCH OF -SN WILL DROP S AND AFFECT MOST OF THE
FCST AREA...THOUGH NRN KS COULD ONLY SEE FLURRIES...IF THAT. THIS
SWD TREND IS SEEN VIA 00Z/06Z NAM LOW-LEVEL RH.

LIFT: THE "BEST" LIFT /QG FORCING COUPLED WITH WEAK FGEN AND MODEST
MID-LEVEL INSTABILITY/ OCCURS UNTIL 18Z WHEN TROF PASSES AND
SUBSIDENCE TAKES OVER. OVERALL MAGNITUDE OF LIFT IS UNIMPRESSIVE AND
IS MOSTLY BELOW THE DENDRITIC GROWTH ZONE /DGZ/. THIS WILL RESULT
IN MOSTLY SMALLER RIMED FLAKES. SO EXPECT LOWER SNOW-LIQUID
RATIOS.

SNOWFALL: AS WE SEE IT NOW A HALF INCH OR LESS ALONG AND N OF I-80
WITH AROUND 1 INCH OVER PARTS OF VALLEY/SHERMAN COUNTIES AND
GREELEY/HOWARD COUNTIES COULD END UP CLOSE. JUST A DUSTING FROM HWY
6 UP TO I-80.

WHERE CAN THIS ACCUM FCST BREAK DOWN? VALLEY/GREELEY COUNTIES. THE
4KM NMM SNOW ALGORITHM OUTPUTS UP TO 3.5 INCHES. BELIEVE THIS IS A
LOW PROBABILITY...BUT SOMETHING TO MONITOR AS WE ARE WATCHING THE
THE 30 DBZ SNOWBAND DROPPING SLOWLY DUE S ON LXN RADAR /FROM CNTRL
CHERRY COUNTY E TO AINSWORTH AND ONEIL/. ANW VSBY HAS AVERAGED 2 SM
AND HAS BEEN AS LOW AS 1 1/2 SM. LESSER QUALITY OF DENDRITES/SMALLER
FLAKE SIZES WILL PROBABLY KEEP ACCUMS BELOW ADVISORY LEVEL /3
INCHES/. IF THIS BAND HOLDS TOGETHER...WE COULD SEE 1" IN DAWSON/
BUFFALO COUNTIES.

THE COBB ALGORITHM OFFERS 1.4 AT ORD FROM THE 08Z RAP AND 2.4 FROM
THE 00Z NAM. HOWEVER...GIVEN ITS SNOW:LIQUID RATIOS LOOK INFLATED
GIVEN WEAK VERTICAL MOTION.

UNCERTAINTIES: HOW FAR S WITH THE SNOW FALL? WE COULD BE A LITTLE
TOO FAR S WITH POPS FOR MEASURABLE LIQUID EQUIV. RAP/NAM SOUNDINGS
HAVE A REMNANT DRY LAYER BELOW 4K FT UNTIL 16Z AT HSI. ALSO UNSURE
HOW QUICKLY TO DECREASE CLOUD COVER BY 21Z. WE SEE THE CLEAR SKIES
OVER NRN SD ON SATELLITE.

AFTER 18Z...PCPN INTENSITY WILL DROP OFF SIGNIFICANTLY AND BY 21Z
SKIES SHOULD START SEE CLEARING.

MODEL DWPTS LOOK TOO LOW ONCE SNOW BEGINS. SO INCREASED DWPTS WHERE
WE EXPECT SNOW TO BE FALLING TO CLOSE DWPT DEPRESSIONS.

TEMPS PROBABLY GO NOWHERE OVER NEB THRU MIDDAY. AS CLOUDS START TO
THIN FROM THE N IN THE AFTN...THEN WE SHOULD SEE SOME RISE. OVER NRN
KS THINNER CLOUDS IN THE MRNG WILL ALLOW FOR SOME RISE WHICH
PROBABLY STALLS MIDDAY IN THICKENING CLOUDS.

TNGT: M/CLEAR. HIGH PRES DRIFTS S OF THE FCST AREA. WINDS TURN LIGHT
OR CALM IN THE EVNG THEN DEVELOP FROM THE SW. TEMPS ARE BIAS
CORRECTED BLEND OF 2M TEMPS AND THE PREVIOUS GID FCST IN AN ATTEMPT
TO CAPTURE BIG RADIATORS /ODX AND LXN/. EXPECT TEENS MOST LOCATIONS
EXCEPT FROM HDE-HSI-GRI WHICH WILL REMAIN IN THE LOW 20S.

WITH FRESH SNOWCOVER AND WINDS EXPECTED TO GO CALM AT ORD...WOULDN`T
BE SURPRISED TO SEE TEMPS END UP IN THE SINGLE DIGITS THERE!

TUE: SUNNY AND BREEZY AS TEMPS RETURN TO NORMAL /43-55F/. SW WINDS
GUST 20-30 MPH.

TUE NGT: M/CLEAR WITH LIGHT/CALM WINDS. ANOTHER COLD NGT WITH AREAS
IN VICINITY OF LEXINGTON/ORD IN THE TEENS AGAIN. USED BIAS CORRECTED
GUIDANCE TO HELP WITH THESE USUAL COLD SPOTS AND THEIR ASSOCIATED
TEMP CURVES...ESPECIALLY IN RAPID DROP-OFF IN THE EVNG.

WED: SUNNY. A LITTLE WARMER AND LESS WIND. 46-59F WHICH IS ABOUT 5F
ABOVE NORMAL.

WED NGT: M/CLEAR WITH A LIGHT SW WIND. 21-32F. ORD PROBABLY GOES
CALM FOR A TIME A DECOUPLES AGAIN.

LONG TERM...THURSDAY THROUGH SUNDAY...AN UNSEASONABLY WARM AND DRY
STRETCH OF WEATHER APPEARS TO BE ON TAP FOR THE LOCAL AREA AS AN
UPPER LEVEL RIDGE OF HIGH PRESSURE FLATTENS OUT OVER THE PLAINS AND
A FAIRLY ZONAL TO SOUTHWESTERLY FLOW ESTABLISHES ITSELF ALOFT...WITH
NO NOTABLE DISTURBANCES CAUGHT IN THIS FLOW TO SPEAK OF.

THE 12Z RUN OF THE EC DID HINT AT A WEAK DISTURBANCE POTENTIALLY
CROSSING THE LOCAL AREA DURING THE FRIDAY NIGHT/SATURDAY MORNING
TIME PERIOD...BUT THE 00Z RUN NOW INDICATES A MORE DIFFUSE UPPER
LEVEL DISTURBANCE...AND THE GFS STEERS THIS SAME UPPER LEVEL ENERGY
WELL TO OUR NORTH. AS A RESULT...MAINTAINED DRY FORECAST THROUGH
NEXT WEEKEND...WITH TEMPERATURES POTENTIALLY CLIMBING INTO THE UPPER
50S AND LOWER 60S FRIDAY THROUGH SUNDAY...WITH LOW TEMPERATURES
EXPECTED TO REMAIN ABOVE FREEZING OVER THE SAME TIME PERIOD. NORMAL
HIGH TEMPERATURES OVER THIS TIME FRAME GENERALLY RUN IN THE LOWER 40S
AND NORMAL LOW TEMPERATURES RUN IN THE LOWER 20S.

LOOKING BEYOND THE CURRENT EXTENT OF THE FORECAST...NO HINTS AT AN
END TO THIS WARM A DRY PERIOD IN MODEL DATA THROUGH AT LEAST THE
MIDDLE OF FOLLOWING WEEK AT THIS TIME.

CLIMATE...WITH THE END OF THE YEAR NOW IN SIGHT...IF ANOTHER 2.16
INCHES OF LIQUID PRECIPITATION DOES NOT ACCUMULATE AT THE CENTRAL
NEBRASKA REGIONAL AIRPORT IN GRAND ISLAND...2012 STANDS TO BE THE
DRIEST FULL YEAR ON RECORD SINCE 1896...WHEN THE FIRST FULL YEAR OF
RECORD KEEPING BEGAN IN THE GRAND ISLAND AREA.

.GID WATCHES/WARNINGS/ADVISORIES...

NE...NONE.
KS...NONE.

SHORT TERM...HALBLAUB
LONG TERM/AVIATION...ROSSI

AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

529 AM CST MON NOV 26 2012

.UPDATE...

.AVIATION...
IFR IS EXPECTED THROUGH ROUGHLY 16-18Z THIS AM AS THE SNOW AND LOW
CIGS GRADUALLY WEAKEN. NOTE THE SNOW ARRIVAL AT KLBF IS BASED ON
THE CURRENT RADAR TRENDS WHICH COULD CHANGE AT ANY TIME AS AN
UPPER LEVEL KICKER ACROSS NERN WYOMING THIS MORNING APPROACHES
WHICH WOULD CAUSE THE SNOW BAND TO FALL APART. ALSO THE SNOW
ENDING TIME AT KVTN IS ESSENTIALLY A MODEL GUESS AS THE RADAR IS
OVERSHOOTING THE SNOW AT THAT LOCATION SUGGESTING THE SNOW WILL
END AT ANY TIME.

VFR COULD BE WIDESPREAD BY 18Z AND CONTINUE OVERNIGHT AS HIGH
PRESSURE BUILDS INTO THE REGION.

.PREV DISCUSSION... /ISSUED 437 AM CST MON NOV 26 2012/

THE FRONTOGENETICALLY FORCED SNOW BAND ACROSS THE SANDHILLS IS
SHOWING SIGNS OF TIGHTENING UP AS VERY COLD 700MB AIR DRIVES SOUTH
AND COLLIDES WITH WARM MID LEVEL TO THE SOUTH NEAR KLBF.

PREV DISCUSSION... /ISSUED 351 AM CST MON NOV 26 2012/

AVIATION...EXPECTING MAINLY MVFR CONDITIONS WITH 5SM -SN AT KVTN
THROUGH 12Z.VFR CONDITIONS SHOULD PREVAIL BY 15Z.

.LBF WATCHES/WARNINGS/ADVISORIES...WINTER WEATHER ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
NEZ004>006-008>010-023>028-094.

SHORT TERM/EXTENDED...CDC
AVIATION...CDC

AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

437 AM CST MON NOV 26 2012

.UPDATE...
REPORTS FROM FROM THE NEBRASKA DEPARTMENT OF ROADS AND RADAR
SUGGEST SNOW WILL CONTINUE TO ACCUMULATE ON ROADWAYS THROUGH
AT LEAST SUNRISE. ADDITIONAL COUNTIES HAVE BEEN ADDED TO THE
WINTER WEATHER ADVISORY. TEMPERATURES CONTINUE TO FALL INTO THE
LOWER 20S ACROSS NRN NEBRASKA SUGGESTING A HIGH PROBABILITY OF
ICING ON ROADWAYS WITH ROAD SFCS LIKELY CROSSING THE FREEZING
MARK.

THE FRONTOGENETICALLY FORCED SNOW BAND ACROSS THE SANDHILLS IS
SHOWING SIGNS OF TIGHTENING UP AS VERY COLD 700MB AIR DRIVES SOUTH
AND COLLIDES WITH WARM MID LEVEL TO THE SOUTH NEAR KLBF.

.PREV DISCUSSION... /ISSUED 351 AM CST MON NOV 26 2012/

AVIATION...EXPECTING MAINLY MVFR CONDITIONS WITH 5SM -SN AT KVTN
THROUGH 12Z.VFR CONDITIONS SHOULD PREVAIL BY 15Z.

.LBF WATCHES/WARNINGS/ADVISORIES...WINTER WEATHER ADVISORY UNTIL NOON
CST /11 AM MST/ TODAY FOR NEZ004>006-008>010-023>028-094.

SHORT TERM/EXTENDED...CDC
AVIATION...CDC

AREA FORECAST DISCUSSION

NWS HASTINGS NE

416 AM CST MON NOV 26 2012

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT