FXUS61 KALY 210906 AFDALY AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ALBANY NY 506 AM EDT SUN MAR 21 2010 .SYNOPSIS... THE COLD FRONT THAT MOVED ACROSS THE REGION SATURDAY WILL STALL TO OUR SOUTH ACROSS THE NEW YORK METROPOLITAN AREA TODAY. LOW PRESSURE OVER THE DEEP SOUTH WILL MOVE NORTHEASTWARD ALONG THE BOUNDARY REACHING THE OHIO VALLEY MONDAY AND SOUTHERN NEW ENGLAND DURING THE DAY TUESDAY. AS THE LOW APPROACHES...A STEADY RAIN WILL OVERSPREAD THE AREA MONDAY WITH RAIN CONTINUING THROUGH TUESDAY. && .NEAR TERM /THROUGH TONIGHT/... WEAK SURFACE HIGH PRESSURE CENTERED TO OUR NORTH OVER QUEBEC WILL MOVE EASTWARD ACROSS NORTHERN NEW ENGLAND. IN THE MEANTIME...THE COLD FRONT THAT MOVED ACROSS THE REGION SATURDAY WILL STALL TO OUR SOUTH ACROSS THE NEW YORK METROPOLITAN AREA. DESPITE THE SURFACE HIGH MID AND HIGH LEVEL CLOUDS WILL DOMINATE THE REGION TODAY AND TONIGHT. THERE IS LITTLE FORCING PRESENT AND ATMOSPHERE RATHER DRY SO CHANCES FOR PRECIPITATION ARE RATHER LOW TODAY AND TONIGHT. AS FOR TEMPERATURES TODAY DESPITE THE CLOUD COVER ANOTHER ABOVE NORMAL DAY. EXPECTING HIGHS INTO THE 60S UP THE HUDSON RIVER VALLEY WITH 40S ACROSS THE SOUTHERN ADIRONDACKS AND 50S ELSEWHERE. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... THE CUT OFF LOW AND ITS ASSOCIATED SURFACE LOW WILL MOVE NORTHEASTWARD ALONG A NEARLY STATIONARY BOUNDARY. THE STORM IS EXPECTED TO REACH THE OHIO VALLEY ON MONDAY AND MOVE TOWARD THE NORTHEAST MONDAY NIGHT. AS THE LOW APPROACHES AND ITS ASSOCIATED LOW LEVEL JET...25 TO 30 KNOTS...MOVES INTO THE REGION...A STEADY RAIN WILL OVERSPREAD THE AREA DURING THE DAY MONDAY AND CONTINUE MONDAY NIGHT. THE MODELS ARE IN AGREEMENT THAT THE CUT OFF LOW WILL TRANSITION INTO THE LONGWAVE TROUGH TUESDAY AND WILL SHOULD SEE A JUMP IN ENERGY AT THE SURFACE TO THE SOUTHERN NEW ENGLAND...CAPE COD AREA. THE RAIN WILL CONTINUE ON TUESDAY AND GRADUALLY TAPER OFF SOUTHWEST TO NORTHEAST TUESDAY NIGHT WITH COLDER AIR FILTERING IN CHANGING THE LINGERING RAIN TO SNOW ESPECIALLY ACROSS THE HIGHER TERRAIN. ONLY LIGHT ACCUMULATION ARE EXPECTED AT THIS TIME. AS FOR QPF AMOUNTS...THE SREF AND MREF PLUMES HAVE BEEN FAIRLY CONSISTENT INDICATING AROUND AN INCH FOR ALBANY. THE MODELS ARE NOT PAINTING A CLEAR PICTURE ON QPF AMOUNTS AND DISTRIBUTION. THE 00Z/SUNDAY NAM12 DID COME IN WITH MUCH HIGHER QPF AMOUNTS BUT THE 06Z/SUNDAY NAM12 RUN HAS PULLED BACK. GENERALLY 1 TO 2 INCHES OF RAIN IS EXPECTED AT THIS TIME WITH SOME LOCALLY HIGHER AMOUNTS EXCEEDING 2 INCHES POSSIBLE. IN ADDITION TO THE RAINFALL...SNOWMELT WILL CONTINUE ACROSS THE HIGHER TERRAIN. A FLOOD WATCH MAY BE NEEDED. AT THIS TIME WILL CONTINUE TO HIGHLIGHT IN THE HAZARDOUS WEATHER OUTLOOK WITH A FOCUS SOUTH AND EAST OF THE CAPITAL DISTRICT. REFER TO THE HYDROLOGY SECTION FOR MORE DETAILS. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... THE EXTENDED OPENS WITH THE PESKY CUTOFF LOW THAT WILL BRING THE WET WEATHER MON INTO TUE...LIFTING NORTH AND EAST TOWARDS NOVA SCOTIA. ISOLD-SCT RAIN OR SNOW SHOWERS WILL PERSIST FROM THE CAPITAL REGION NORTH AND EAST ON WED. H850 TEMPS DIP BACK WELL BELOW 0C ACROSS THE REGION...AS MAX TEMPS WILL TREND CLOSER TO NORMAL VALUES FOR MARCH. THE FIRST IN A SERIES OF COLD FRONTS WILL APPROACH THE REGION LATE IN THE DAY. WED NIGHT...A COLD FRONT WILL SWING THROUGH WITH STRONG COLD AIR ADVECTION ENCROACHING THE REGION. THERE WILL BE ISOLD-SCT SNOW SHOWERS AROUND. THE GFS HAS H850 TEMPS PLUMMETING TO -5C TO -10C OR SO ACROSS THE REGION BY 1200 UTC THU. THU INTO FRI...SFC HIGH PRESSURE WILL RIDGE IN FROM THE OHIO VALLEY ON THU WITH DRIER WEATHER. A STRONG NRN STREAM DISTURBANCE WILL APPROACH THE NRN GREAT LAKES ON THU. THE COLD FRONT IS SITUATED ALONG THE THE LEADING EDGE OF THE POLAR VORTEX. THE ECMWF/GFS/GLOBAL ENSEMBLES HAVE THIS FRONT DIVING SOUTHEAST ACROSS THE REGION THU NIGHT INTO EARLY FRIDAY. IT WILL BECOME BLUSTERY AND COLD. TEMPS MAY ACTUALLY FALL SOME DURING THE DAY...AS MID LEVEL THICKNESSES DROP INTO THE 510-530 DECAMETER RANGE. THE GEFS HAVE H850 TEMPS 1-2 STANDARD DEVIATIONS BELOW NORMAL. THERE WILL LIKELY BE A BATCH OF -SHRA/-SHSN/S WITH THE FRONT. SATURDAY...NW FLOW ALOFT DOMINATES ASSOCIATED WITH A STRONG UPPER LEVEL TROUGH OVER ERN CANADA AND THE NORTHEAST. H850 TEMPS SATURDAY MORNING COULD BE AROUND -15C OVER THE CAPITAL REGION. MAX TEMPS WILL BE A FAR CRY FROM THIS CURRENT WEEKENDS WELL ABOVE NORMAL READINGS. EXPECT MAX TEMPS TO BE IN THE MID TO UPPER 30S OVER THE MTNS...AND LOWER TO MID 40S IN THE VALLEYS. OVERALL...PCPN LOOKS BELOW NORMAL IN THE LONG TERM...BUT TEMPS WILL TREND BACK NORMAL TO SLIGHTLY BELOW NORMAL READINGS. && .AVIATION /09Z SUNDAY THROUGH THURSDAY/... SFC HIGH PRESSURE CONTINUES TO BUILD IN FROM QUEBEC WITH THE COLD FRONT BECOMING STATIONARY OVER LONG ISLAND...EXTREME SOUTHERN NEW ENGLAND...NRN NJ...AND PA THIS MORNING. VFR CONDITIONS WILL PREVAIL THE NEXT 24 HOURS WITH PLENTY OF MID AND HIGH CLOUDS AROUND NORTH OF THE BOUNDARY. THERE IS NOT MUCH FORCING NORTH OF THE BOUNDARY WITH PERHAPS A FEW SPRINKLES OUT OF A MID LEVEL DECK OF CLOUDS IN THE LATE MORNING/AFTERNOON FROM KALB NORTHWARD. WE PLACED A FEW VCSH GROUPS THERE. FOLLOWED THE NAM SOUNDING PROFILES FOR THE PERIOD WHICH WERE DRIER IN THE LOW LEVELS. WINDS WILL BE LIGHT FROM THE N/NW THIS MORNING AT 5 KTS OR LESS. THEY WILL BE VARIABLE FROM THE E/SE AT AROUND 5 KTS OR LESS...AND WILL BECOME LIGHT TO CALM SUNDAY EVENING. OUTLOOK... MON AM...MAINLY VFR...CHC -SHRAS. MON PM-TUE...MVFR/IFR CIGS AND VSBYS WITH PERIODS OF RA. TUE NGT...IMPROVING TO VFR...NO SIG WX. WED-WED NIGHT...VFR...SLIGHT CHC -SHRA/-SHSN N/NW OF KALB. THU...VFR...NO SIG WX. && .FIRE WEATHER... THE COLD FRONT THAT MOVED ACROSS THE REGION SATURDAY WILL STALL TO OUR SOUTH ACROSS THE NEW YORK METROPOLITAN AREA TODAY. LOW PRESSURE OVER THE DEEP SOUTH WILL MOVE NORTHEASTWARD ALONG THE BOUNDARY REACHING THE OHIO VALLEY MONDAY AND SOUTHERN NEW ENGLAND DURING THE DAY TUESDAY. AS THE LOW APPROACHES...A STEADY RAIN WILL OVERSPREAD THE AREA MONDAY WITH RAIN CONTINUING THROUGH TUESDAY. MINIMUM RELATIVE HUMIDITY VALUES THIS AFTERNOON WILL BE 40 TO 50 PERCENT WITH 50 TO 60 PERCENT ACROSS THE SOUTHERN ADIRONDACKS. RELATIVE HUMIDITY VALUES WILL RECOVER TO NEAR 100 PERCENT AND RAIN WILL OVERSPREAD THE AREA MONDAY. && .HYDROLOGY... SUNDAY WILL BE MAINLY DRY ACROSS THE REGION WITH HIGH PRESSURE DOMINATING FROM QUEBEC. DIURNAL SNOW MELT WILL CONTINUE TO INCREASE STREAM AND RIVER FLOWS IN THE ADIRONDACKS...CATSKILLS... BERKSHIRES...SOUTHERN VERMONT...AND OTHER AREAS WHERE SNOW REMAINS. THERE IS STILL 4 TO 10 INCHES OF WATER IN THE SNOWPACK OVER AREAS OF THE ADIRONDACKS...CATSKILLS...SOUTHERN GREEN MOUNTAINS...AND BERKSHIRES. A CUTOFF LOW WILL MOVE INTO THE MID ATLANTIC REGION MONDAY NIGHT. THIS STORM HAS THE POTENTIAL TO BRING ONE TO ONE AND A HALF INCHES OF RAIN TO THE FORECAST AREA STARTING MONDAY AFTERNOON AND ENDING TUESDAY AFTERNOON. SOME LOCALLY HIGHER AMOUNTS EXCEEDING 2 INCHES COULD OCCUR ALONG THE EAST FACING SLOPES OF THE CATSKILLS AND ADIRONDACKS. THE HEAVIEST RAINFALL WILL OCCUR MONDAY NIGHT THRU TUESDAY MORNING. SOME WET SNOW MAY OCCUR OVER THE SRN ADIRONDACKS...AND SRN GREEN MTNS TUESDAY NIGHT. THE RUNOFF FROM THIS RAIN ALONG WITH MELTING SNOW...SATURATED GROUND AND HIGH EXISTING FLOWS ON THE HOUSATONIC RIVER...AND ERN CATSKILLS BASINS MAY RESULT IN THE POSSIBILITY OF STREAMS AND RIVERS OVERFLOWING THEIR BANKS STARTING TUESDAY MORNING. IF THE POSSIBILITY OF FLOODING BECOMES MORE DEFINITE...THEN A WATCH MAY BE ISSUED. THE MOST VULNERABLE LOCATIONS FOR POTENTIAL HYDRO ISSUES APPEAR TO BE SOUTH AND EAST OF THE CAPITAL DISTRICT AT THIS TIME. PLEASE REFER TO THE WINTER/SPRING FLOOD OUTLOOK /ALBESFALY/ FOR MORE DETAILS ON THE POTENTIAL FOR SPRING FLOODING. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS... PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...IAA NEAR TERM...IAA SHORT TERM...IAA LONG TERM...WASULA AVIATION...WASULA FIRE WEATHER...IAA HYDROLOGY...WASULA