-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBGM 120616
AFDBGM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BINGHAMTON NY
216 AM EDT WED MAR 12 2014

.SYNOPSIS...
A POTENT WINTER STORM SYSTEM WILL BRING A WINTRY MIX RANGING FROM
RAIN IN NORTHEAST PENNSYLVANIA TO HEAVY SNOW ALONG AND NORTH OF
THE NEW YORK THRUWAY ON WEDNESDAY. THE WINTRY MIX WILL DRIVE SOUTH
BY WEDNESDAY NIGHT WITH A SHARP CHANGE BACK TO ALL SNOW. THE
WINTRY GRIP WILL TAKE HOLD AGAIN THROUGH THURSDAY WITH CONTINUED
SNOW SHOWERS AND TEMPERATURES STRUGGLING TO GET OUT OF THE TEENS.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
1030 PM UPDATE...
ALL THINGS STILL LOOK ON TRACK FOR IMPENDING WINTER STORM. STRONG
H5 TROF DIGGING THRU PLAINS STATES AT THIS TIME WITH 998MB SFC LOW
NOW SITTING ACRS THE OZARKS. LGT ECHOES ARE BREAKING OUT IN AREA
OF RRQ OF UL JET STREAK CURRENTLY MVG THRU SRN CANADA. HWVR, WITH
LOWEST 200-300MB OF THE ATMOSPHERE DRY, ONLY AN OCNL SPIT CAN
SNEAK THRU, THUS HV KEPT TONIGHT DRY THRU 06Z WHEN UPGLIDE
COMMENCES ON 285K LYR AND MOST OF THE FA BREAKS OUT IN
PRECIPITATION.

ACRS THE FAR NORTH, LATEST NAM HAS H9 TEMPS ABV 0C FM 06Z-09Z THEN
QUICKLY DROPPING BLO ZERO. THUS HV GONE WITH MORE OF A RAIN/SNOW
MIX ACRS NRN ZONES THRU 09Z BFR BCMG ALL SNOW.

WL LV THE FINER DETAILS TO LATER SHIFTS ON TIMING OF CHANGEOVER
WHEN MORE MODELS ARE AVAILABLE, HWVR 00Z NAM AS WELL AS 12Z EURO
INDICATED WED BTWN 18Z AND 00Z WL BE PRIMETIME FOR HEAVIEST SNOW
TO FALL IN AN ONEIDA TO YATES LINE WITH LATEST NAM INDICATING UP
TO 1 INCH OF QPF IN THIS TIME. WHILE THIS SEEMS TO BE OVERDONE,
CANNOT RULE OUT 0.6 TO 0.7 INCHES THAT WPC IS FCST DRG THIS TIME.
INTERESTING TO NOTE THAT THIS AREA IS IN THE COUPLED JET LOCATION
OF 250MB SPEED MAXES AND ALSO IN THE REGION OF STRONGEST
FRONTOGENETICAL FRCG.

PREV DISCOS BLO...

730 PM UPDATE...
TEMPS LOOK TO BE ON TRACK FOR TONIGHT WITH MINS PROJECTED TO BE IN
THE LWR 30S ACRS THE FAR NORTH AND FALLING FM THERE. FURTHER TO
THE SOUTH EXPECT TEMPS TO DROP INTO THE M/U 30S AND RISE THRU THE
MRNG BFR DROPPING FM THERE. HV UPDATED GRIDS TO RMV MENTION OF
PCPN FOR TONIGHT AS ATMOSPHERE IS TAKING AWHILE TO SATURATE. MOST
ECHOES ON REGIONAL RADARS LOOK TO BE MID-CLOUD.

EXPECT THESE SHUD BEGIN TO SATURATE DOWN TWD MIDNIGHT ACRS THE
WEST AND PROGRESS EAST FM THERE. THERMAL PROFILES LOOK TO BE CLD
ENUF FOR ALL SNOW ACRS EXTRM NRN ZONES, WHILE SYRACUSE AREA LOOKS
TO BE RIGHT ON THE EDGE OF RAIN/SNOW LINE, THO THIS LOOKS TO ONLY
BE FOR A COUPLE OF HRS. AREAS CLOSER TO THE SRN TIER LOOK TO START
OFF AS ALL RAIN AND SLOWLY TRANSITION DRG THE MRNG HRS.

12Z EURO AND 18Z NAM INDICATING HEAVIEST SNOW SHUD FALL BTWN 18Z
AND 00Z TOMORROW ACRS NRN ZONES FM ONEIDA SWRD TWD YATES CNTY IN
THE CLD AIR. THIS IS IN AGREEMENT WITH LATEST WPC QPF GRIDS. THIS,
COMBINED WITH FRONTOGENESIS BEING SHOWN BY ALL MODELS FOR THIS
AREA MIGHT LEAD TO HIGHER SNOW TOTALS DRG THE AFTN.

4 PM UPDATE...
SPRING LIKE CONDITIONS...WHICH GOT A LITTLE AHEAD OF OUR
FORECASTS...TODAY WILL ABRUPTLY END IN THE NEXT 24 HOURS. THIS
EVENING LOOKS TRANQUIL AND RATHER MILD AS TEMPERATURES GRDLY FALL
BACK INTO THE 30S. LOW PRESSURE MOVING OUT OF THE MIDWEST WILL
BEGIN TO INFLUENCE WESTERN PORTIONS OF CENTRAL NEW YORK AS ISENTROPIC
LIFT INCREASES AHEAD OF WARM FRONT. TEMPERATURES OVERNIGHT ARE
MARGINAL AT THE SURFACE. MOST AREAS WILL START OFF AS A LIGHT
RAIN...MIXING WITH SOME SNOW ACROSS THE NORTH.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
STORM WILL MOVE THROUGH THE REGION ON WEDNESDAY AND WEDNESDAY
NIGHT WITH MANY FORECAST CONCERNS BOTH IN TIME AND GEOGRAPHIC
SPACE. BREAKING IT DOWN...

CHANGES...UPGRADED PREVIOUS ADVISORY TO LOW END WARNING. ADDED
NEXT GROUP OF COUNTIES SOUTHWARD ACROSS THE SRN TIER NY INTO AN
ADVISORY.

WHY?...12Z GFS SHOWED GOOD RUN-RUN CONSISTENCY AND STILL HAD A
SLIGHTLY WARM PROFILE ALOFT. LOOKED SIMILAR TO 00Z ECMWF AND QUICK
LOOK AT 12Z EURO SAYS THE SAME THING. 12Z NAM IMPROVED POSITION AND
TRACKING OF SFC LOW ACROSS THE MASON-DIXON LINE WHICH IS NOW
SIMILAR WITH OTHER MODEL CONSENSUS...BUT WAS A BIT COOLER ON
THERMALS. SO...SYNOPTICALLY THE SOLUTION LOOKS PRETTY CLOSE
NOW...BUT THE DETAILS OF THE THERMAL PROFILES UNFORTUNATELY ARE
WHAT WE ARE COUNTING ON SINCE WE ARE IN THE BATTLE ZONE. IN ORDER TO
RETAIN SOME CONSISTENCY IN THE FCST...WE EQUALLY BLENDED THE PREV
FORECAST WITH THE NEW GUIDANCE. THIS COOLED THINGS JUST ENOUGH TO
INCREASE SNOW-LIQUID RATIOS AND ALSO TIMING OF SOUTHWARD PUSH OF
COLDER AIR TOMORROW AFTN AND EVENING. GOOD FRONTOGENETIC FORCING
TO THE NORTH OF THE 850 MB LOW WHICH IS PROGGED TO MOVE ACROSS
NORTHERN PA SUGGESTS HEAVY PRECIP CENTRAL AND NRN NY. BLENDED QPF
AMOUNTS ACTUALLY LOOK REASONABLE WITH AREAS OVER 1 INCH LIQUID.

WITH SOME AREAS NOW BEING IN THE COLDER AIRMASS...AND LONGER...THE
SNOW ACCUMULATION NUMBERS ARE SHAKING OUT HIGHER AND A LITTLE
FURTHER SOUTH...ESPECIALLY SINCE MODELS SUGGEST THE DEFORMATION
ZONE SNOWS ON THE BACK SIDE OF DEEPENING CYCLONE WILL LINGER
THROUGH MUCH OF WEDNESDAY EVENING. THIS CAUSED THE PREVIOUS
ADVISORY AREA ACCUMS TO JUST NUDGE INTO WARNING CRITERIA AND
FORCED THE NEXT GROUP OF COUNTIES INTO ADVISORY. THINGS TO NOTE
ARE THAT MUCH OF THIS SNOWFALL IN THE SOUTHERN TIER AND CATSKILLS
WILL BE TOMORROW AFTERNOON AND NIGHT...WHILE MUCH OF THE NORTH
WILL BE IN IT ALL DAY. FOR NORTHEAST PA...THE TRANSITION TO COLDER
WEATHER OCCURS LATE WITH A BRIEF PERIOD OF MIXED PRECIP AND SNOW.
LIGHTER ACCUMS THERE DO NOT WARRANT ANY HIGHLIGHTED PRODUCTS.
NEEDLESS TO SAY...OUR CONFIDENCE IS LOW ON THE SNOW ACCUMULATIONS
AND ANOTHER SUBTLE JOG TO THE EXPECTED TEMPERATURES COULD CAUSE
MORE CHANGES.

WHAT EVERYONE SHOULD ALSO NOTE...IS THE RAPID TRANSITION TO MUCH
COLDER WEATHER AND BLUSTERY CONDITIONS AS THE DEEPENING LOW MOVES
EAST DURING THE AFTERNOON. THERE COULD BE A FLASH FREEZE ON AREA
ROADS THAT HAVE BEEN WET FROM EITHER MELTING SNOW TODAY AND
TONIGHT...TO RAIN...SLEET OR WET SNOW.

BEYOND THIS HODGE PODGE OF CONFUSING WEATHER...THE BITTER COLD OF
WINTER INFUSES THE REGION AGAIN THROUGH THURSDAY WITH HIGHS
STRUGGLING TO GET OUT OF THE TEENS...AND THEY PROBABLY WON/T. SNOW
SHOWERS WILL BE LIKELY OFF THE BIG LAKE UP NORTH...AND SCATTERED
TO FLURRIES FURTHER SOUTH. THE PROBLEM FOR THURSDAY MAY BE
SIGNIFICANTLY STRONG WIND GUSTS AND THE THREAT FOR DANGEROUS WIND
CHILLS. THIS HAS CURRENTLY BEEN ADDRESSED IN THE WINTER WEATHER
PRODUCTS ON THE STREET NOW...BUT MAY NEED THEIR OWN HEADLINES
LATER ON AS THE SNOW PROBLEMS DIMINISH.

TEMPERATURES WEDNESDAY ARE NOT EXPECTED TO BEHAVE NORMALLY...AND
FALL THROUGH THE DAY AND NIGHT. WELL BELOW NORMAL HIGHS THURSDAY
AND COLD THURSDAY NIGHT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
2 PM UPDATE...

FOLLOWED WPC GUIDANCE. CONTINUED UNSETTLED AND COLDER THAN NORMAL.
FRIDAY DRY WITH WAA ON BACK SIDE OF A LARGE HIGH OVER THE MID
ATLANTIC. A LOW DROPS SE INTO THE UPPER LEVEL TROF BRINGING A PAIR
OF COLD FRONT THROUGH THE CWA FRI NGT AND SAT. ENOUGH WARM AIR
AHEAD OF IT SO PRECIP WILL BE MIXED. ANOTHER COLD FRONT GOES
THROUGH SAT NGT FOLLOWED BY ANOTHER ROUND OF LAKE EFFECT SNOW.
MONDAY AN ARCTIC HIGH CENTERED OVER THE CWA SO DRY AND COLD.
TUESDAY ANOTHER SYSTEM COMES IN WITH MOSTLY SNOW.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
OUTSIDE OF KAVP, WIDESPREAD RESTRICTIONS DEVELOPING THIS MORNING
MAINLY IN LIGHT RAIN. MAINLY MVFR CIGS, WITH IFR VSBYS. UP NORTH
AT KSYR/KRME, COLDER AIR WILL CHANGE TO THE RAIN OVER TO SNOW BY
12Z. ELSEWHERE RAIN IS EXPECTED UNTIL LATER THIS MORNING. READ
BELOW FOR SOME SPECIFICS.

AT KSYR/KRME, VSBYS WILL FALL UNDER 1/2SM FROM 16Z ON, WITH
AIRPORT MINS LIKELY BEING MET THIS AFTERNOON UNDER HEAVY SNOW.
VSBYS IMPROVE SLIGHTLY EARLY TONIGHT BUT INCREASING WINDS ALONG
WITH MODERATE SNOW WILL KEEP VSBYS UNDER 1SM. THESE WILL BE THE
WORST IMPACTED TERMINALS.

AT KITH/KELM, RAIN THIS MORNING WILL TRANSITION TO SNOW BETWEEN
14Z AND 18Z. IFR VSBYS WILL ALREADY BE PRESENT DUE TO THE RAIN,
BUT WITH THE TRANSITION TO SNOW VSBYS WILL FALL UNDER 1SM AND
REMAIN THAT WAY THROUGH EARLY TONIGHT. DURING THE AFTERNOON
AIRPORT MINS MAY BE MET, WITH AT LEAST MODERATE SNOW (1/2SM) BUT
AT TIMES HEAVY (1/4SM).

AT KBGM, THE TRANSITION TO SNOW WILL TAKE LONGER. IFR VSBYS IN
RAIN WILL CONTINUE THROUGHOUT THE DAY, WITH A TRANSITION TO SNOW
BETWEEN 21Z AND 0Z. IFR VSBYS WILL FALL UNDER 1SM DURING THIS TIME
AND CONTINUE THROUGH EARLY TONIGHT. COULD NOT RULE OUT A BRIEF
PERIOD OF HEAVY SNOW WITH AIRPORT MINS BEING MET, BUT NOT AS
CONFIDENT AS I AM FARTHER NORTH AND WEST.

AT KAVP, VFR THROUGH THIS MORNING. LIGHT RAIN DEVELOPS BY 18Z WITH
MVFR CIGS. STEADIER RAIN ARRIVES BY 21Z WITH IFR VSBYS LIKELY. A
QUICK TRANSITION TO SNOW IS EXPECTED BY EARLY TONIGHT, WITH IFR
VSBYS IN LIGHT SNOW DURING THAT TIME.

LIGHT WINDS WILL INCREASE ALL TERMINALS BY EARLY TONIGHT OUT OF
THE NORTHWEST. SUSTAINED 15 TO 20 KTS, WITH GUSTS OVER 30 KTS
LIKELY.


OUTLOOK...

THU...IFR RESTRICTIONS IN SNOW AND BLOWING SNOW WITH GUSTY
NORTHWEST WINDS...DIMINISHING THU AFTERNOON.

THU NGT/FRI...VFR...EXCEPT MVFR AT SYR AND MAYBE ITH RME BGM IN
LES.

FRI NGT TO SUN...MVFR/IFR IN MIXED PRECIP FRI NGT/SAT CHANGING TO
SNOW. MULTIPLE COLD FRONTS.
-- End Changed Discussion --

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
PA...NONE.
NY...WINTER WEATHER ADVISORY FROM NOON TODAY TO 8 AM EDT THURSDAY
     FOR NYZ055>057.
     WINTER STORM WARNING FROM 10 AM THIS MORNING TO 8 AM EDT
     THURSDAY FOR NYZ024-025-044>046.
     WINTER STORM WARNING UNTIL 8 AM EDT THURSDAY FOR NYZ009-
     015>018-022-023-036-037.
-- End Changed Discussion --

&&

$$
SYNOPSIS...JAB
NEAR TERM...JAB/PVN
SHORT TERM...JAB
LONG TERM...TAC
AVIATION...HEDEN