000
FXUS61 KBGM 111225
AFDBGM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BINGHAMTON NY
725 AM EST THU MAR 11 2010

.SYNOPSIS...
A LARGE STORM SYSTEM WILL REMAIN IN PLACE OVER THE MIDWEST THROUGH
THE END OF THE WEEK BEFORE HEADING EAST. THIS SYSTEM WILL
APPROACH THE AREA AND REORGANIZE OVER THE WEEKEND...SPREADING RAIN
INTO THE REGION BEGINNING FRIDAY. RAIN WILL BECOME MORE STEADY ON
SATURDAY AND CONTINUE INTO SUNDAY...WITH HEAVY RAIN POSSIBLE. MILD
TEMPERATURES ARE EXPECTED TO CONTINUE THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 725 AM...GIVEN TRENDS HAVE GONE MORE OPTIMISTIC FOR
TDA`S SKY COVER. RETAINED SLGT CHC POPS FOR PSBLTY OF ISOLD -SHRA
THIS AFTN BUT MOST AREAS TO SEE A PARTLY SUNNY AND DRY DAY. PREV
BLO...

LARGE SCALE CLOSED LOW SPINNING ACRS CENTER HALF OF NATION TONIGHT
IS SPREADING MOISTURE UP INTO THE PLAINS STATES/MS VLY AREA. H5
RIDGING AHD OF SYSTEM HAS HELPED MAINTAIN A MOSTLY DRY AIRMASS ACRS
FA. WK S/WV ASSOC WITH H5 SYSTEM CURRENTLY TRAVERSING UPSTATE NY
WITH AN AREA OF LGT PCPN NOTED ON REGIONAL WSR-88DS. NOTHING BEING
REPORTED WITH THESE ECHOES AND EXPECT ONLY A VRY LGT SHOWER OR
SPRINKLE AS THIS AREA MVS THRU.

S/WV WL LIFT NORTH AND MOSTLY OUT OF THE AREA BY 12Z. BHND
THIS...SUBSIDENCE WL LKLY KEEP FA DRY RMNDR OF THE DAY. CANNOT RULE
OUT AN ISOLD SHOWER OR SPRINKLE AT ANY TIME TODAY BUT NOT MUCH IN
THE WAY OF MEASURABLE PCPN EXPECTED THRU 00Z TONIGHT.

11U-3.9U SATELLITE IMAGERY SHOWS WIDESPREAD CLD CVR ACRS ALL OF NY
STATE. HWVR CLRNG HAS WORKED INTO WRN/CNTRL SXNS OF PA AND IS HEADED
FOR FA. MAY SEE PCLDY SKIES WORK INTO AREAS WEST OF I-81 THIS
MRNG...HELPING BOOST TEMPS AGAIN TO NR 60 DEGREES. HV ONCE AGAIN
TRENDED TWD MET/MAV BIAS-CORRECTED GRIDS AS THEY SEEM TO BE FAIRLY
REASONABLE GIVEN PROGGED H9 TEMPS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
SFC LOW WL SIT AND SPIN OVR CNTRL PLAINS THRU TONIGHT BFR HEADING
EAST INTO THE OH VLY. SFC WMFNT STRETCHED FROM LOW CNTR INTO OH/PA
WL BASICALLY BCM STATIONARY AND SLOWLY WASH OUT. PREVIOUS 00Z RUNS
LIFTED FRONT THRU WITH FAIRLY GOOD SWATH OF RAIN OCCURRING FM FRI
MRNG INTO THE AFTN. LATEST RUNS BRING ONLY LGT RAIN INTO FA DRG THE
DAY FRIDAY. UNTIL THEN VRY LITTLE FRCG EXISTS FOR PCPN AND HV
TRIMMED BACK ON POPS FOR TONIGHT AND EVEN INTO FRIDAY...DROPPING BY
A CATEGORY EACH PD.

MODELS CONT TO ADVERTISE LOPRES CNTR RIDING UP THE EASTERN SEABOARD
FM THE SOUTHEAST WITH OH VLY LOW ULTIMATELY CONSOLIDATING WITH THIS
SYSTEM. PLACEMENT OF THIS SYSTEM WL DETERMINE AXIS OF HEAVIEST QPF.
NAM IS MUCH SLOWER TO BRING SYSTEM NORTHWARD...THO IT DOES DVLP
QUITE A BIT OF PCPN AHD OF FEATURE WITH H8 LLJ OF 50+ KTS PUMPING IN
SIGNIFICANT MOISTURE OFF THE ATLANTIC BY SAT MRNG.

EURO A LITTLE QUICKER MVG SYSTEM NORTH ALTHO IT IS STILL AS DELAYED
ON PCPN...WITH LLM NOT INCRSG SIGNIFICANTLY UNTIL SAT MRNG AND
LIKEWISE FOR THE GFS. STILL APPEARS THAT TARGETED AREAS FOR HVY RAIN
LOOK TO BE NEPA/CATSKILLS WITH 2-3 INCHES POSSIBLE THROUGHOUT THE
WEEKEND. MODELS CONTINUE TO HINT AT LIGHTER AMNTS BACK TO THE NORTH
AND WEST INITIALLY...LKLY DUE TO SHADOWING AFFECT OF HIGHER TERRAIN
TO THE EAST. MAY SEE SOME SHOTS OF HVY QPF LATE IN THE SHORT TERM
WORK NORTH TWD UPSTATE NY AS PCPN AXIS SHIFTS NORTH BFR PULLING EAST
OF AREA.

WL NOT BE ISSUING ANY WATCH PRODUCTS AT THIS TIME DUE TO MODEL
TRENDS IN DELAYING SIGNIFICANT RAINFALL UNTIL SATURDAY. STILL
CONCERNED ABOUT POTENTIAL FOR RIVER FLOODING OVER SRN AND ERN SXNS
OF THE REGION. A LITTLE MORE UNCERTAINTY EXISTS TO THE NORTH AND
WEST. HWVR...ANY MVMNT TO THE NORTH OF THE HVY RAIN WUD PLACE RISK
FOR FLOODING INTO THE UPPER SUSQUEHANNA BASIN. THEREFORE...WL
CONTINUE TO HIGHLIGHT THREAT ACRS THE ENTIRE AREA AS MODERATE RAIN
COMBINED WITH MELTING SNOWPACK POSES A THREAT OVR MUCH OF UPSTATE NY
AND NEPA.

ANOTHER ISSUE FOR CONCERN WL FOCUS ON WINDS LATE IN THE PD. LL WINDS
INCRS FRI NGT AND SAT...WITH H9 WINDS INCRSG TO +40KTS. HIGHER
TERRAIN OF POCONOS/WRN CATS MAY EASILY SEE GUSTS APPCH 45-50MPH DRG
THIS TIME. THIS WL ALSO HELP ACCELERATE LOSS OF SNOWPACK.

TEMPS THRU THE PD WL BE WELL ABV NORMAL WITH AFTN MAXES TOPPING OUT
IN THE 50S EACH DAY. HV GONE ABV MOS GUIDANCE AGAIN ON FRIDAY AND
FRI NGT WHERE MOS GUIDANCE WUD INDICATE SOME FRZG RAIN POTENTIAL
ACRS THE NORTH AND EAST. CANNOT SEE TEMPS DROPPING ANY LOWER THAN
MID-30S...THUS ALL RAIN EXPECTED.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
LITTLE CHANGE TO THE LONG TERM FORECAST. WET START THEN DRYING
BEGINNING OF THE WORK WEEK SO THAT BY WED DRY.

PREVIOUS DISCUSSION...
VERY UNSETTLED CONDITIONS WILL REMAIN UPON US FOR THE START OF
THE EXTENDED PERIOD AS THE LARGE CUTOFF LOW REMAINS ENTRENCHED
ALONG THE EAST COAST. GFS STILL HIGHLY SUPPORTIVE OF A HIGH DEGREE OF
ISENTROPIC ASCENT BEING FOCUSED ALONG THE 295-300K THETA SURFACES
AS A LOW-LEVEL JET OF 65 KTS CONTINUES TO TRANSPORT HIGH AMOUNTS
OF ATLANTIC MOISTURE WESTWARD THROUGHOUT THE DAY ON SUNDAY. QUICK
LOOK AT GFS PWAT VALUES SUGGEST VALUES IN EXCESS OF 1" ACROSS
EASTERN MASS...WITH AN AXIS EXTENDING WEST INTO NORTHERN/CENTRAL
NY. MAIN FORCING ALOFT WILL CONTINUE TO BE MAIN CUTOFF LOW
CENTERED TO THE SOUTH ACROSS THE MID-ATLANTIC...WITH PERIODIC
POCKETS OF ENERGY EXPECTED TO ROTATE INTO THE AREA ALONG ITS
NORTHERN PERIPHERY. TO THE NORTH...UPPER RIDGING WILL BEGIN NOSING
WESTERN QUEBEC...WHICH WILL SUPPORT A WELL DEFINED DEFORMATION
AXIS TO JUST TO THE NORTH. ECMWF AND GFS APPEAR TO BE IN FAIRLY
GOOD AGREEMENT WITH THIS SCENARIO...WITH THE MAIN QPF AXIS
POSITIONED SLIGHTLY FURTHER NORTH ON THE ECMWF. BASED ON THE
ABOVE...FEEL NO REASON NOT TO INCREASE POPS ACROSS
CENTRAL/NORTHERN ZONES IN RESPONSE TO WHERE MODELS ARE BEGINNING
TO AGREE ON PLACEMENT OF MAX QPF AXIS THROUGHOUT THE DAY ON SUNDAY.

PRECIP WILL LIKELY END FROM NORTH TO SOUTH ON MONDAY AS RIDGING TO
THE NORTH BECOMES COMPRESSED IN ADVANCE OF ANOTHER SHORTWAVE
TROUGH SHIFTING SOUTH FROM NORTHERN ONTARIO PROVINCE. GFS/ECMWF
DIFFER SLIGHTLY ON THIS SCENARIO WITH THE LATTER BRINGING THE
SHORTWAVE IN APPROX. 12 HRS LATER (00Z WED). IN ANY
EVENT...HOPEFULLY THE ARRIVAL OF THIS FEATURE WILL BE ENOUGH TO
FINALLY SHUNT THE CUTOFF OUT TO SEA WITH A PERIOD OF DRIER WEATHER
FINALLY IN STORE FOR THE REGION TOWARDS THE CONCLUSION OF THE
FORECAST PERIOD.

&&

.AVIATION /13Z THURSDAY THROUGH MONDAY/...
VFR SHOULD PREVAIL THROUGH 20Z THIS AFTERNOON. A FEW SHOWERS
OUT OF A 7K FT CIG WILL MOVE EAST THROUGH RME DURING THE HOUR.
SATELLITE TRENDS SHOWING SOME SUN MAKING IT TO ELM AND MAYBE THE
REST OF THE TAF SITES EARLY AFTN. LATE AFTN AND THIS EVE CIGS
SHOULD FALL TO MVFR FROM S TO N...AS BETTER MOISTURE COMES IN FROM
THE SE AS THE MID LEVEL WINDS INCREASE. CONFIDENCE MODERATE THAT
MVFR WILL HAPPEN TONIGHT GIVEN CONTINUED MOIST SE UPSLOPE FLOW. A
LITTLE LESS CONFIDENCE FOR SYR AND RME. SOME OF THE GUIDANCE EVEN
HAS IFR CIGS TONIGHT WHICH I DID NOT INCLUDE DUE TO LOW
CONFIDENCE. MOS GUIDANCE HAS BEEN TOO PESSIMISTIC THE LAST
SEVERAL DAYS. AT SOME POINT CIGS WILL FALL TO IFR GIVEN THE
DEEPENING SATURATION...AND THE CONTINUED AND STRENGTHENING SE FLOW
AHEAD OF THE BIG STORM AND OFF THE OCEAN. MOST LIKELY AT BGM...AVP
AND ITH...IN THAT ORDER.

EAST TO SOUTHEAST WINDS AT 5 KTS OR LESS THIS MORNING INCREASING
DURING THE DAY TO 5-10 KT...THEN DROPPING SLIGHTLY TO AROUND 5 KTS
TONIGHT.


OUTLOOK...

FRIDAY INTO SUNDAY NGT...IFR/MVFR IN RAIN/FOG...ESPECIALLY LATE
FRIDAY NIGHT INTO SUNDAY MORNING.

MON...IMPRVG TO VFR.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.

&&

$$
SYNOPSIS...PVN
NEAR TERM...
SHORT TERM...PVN
LONG TERM...CMG
AVIATION...TAC

NWS bgm Office Area Forecast Discussion