FXUS61 KALY 222115
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
415 PM EST TUE DEC 22 2009
.SYNOPSIS...
HIGH PRESSURE...CENTERED SOUTH OF HUDSON BAY...WILL DOMINATE OUR
WEATHER THROUGH THURSDAY...WITH COLD AND MAINLY DRY WEATHER. A WEAK
DISTURBANCE WILL BRING SOME CLOUDS AND SCATTERED SNOW SHOWERS MAINLY
NORTH OF ALBANY LATE TONIGHT INTO WEDNESDAY. A LOW PRESSURE SYSTEM
WILL MOVE NORTH FROM THE SOUTHERN PLAINS INTO CENTRAL CANADA LATE IN
THE WEEK...WHICH WILL LIKELY BRING MIXED PRECIPITATION TO OUR REGION
STARTING FRIDAY NIGHT AND LINGERING INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
QUIET WEATHER WITH A VIRTUALLY CLEAR CLOUD SKY OVER OUR REGION.
TEMPERATURES ONCE AGAIN WELL BELOW NORMAL AND MOSTLY BELOW FREEZING.
THE ONLY EXCEPTION IS ACROSS OUR EXTREME SOUTHERN AREAS WHERE TO THE
LEE OF THE CATSKILLS...TEMPERATURES HAVE MUSCLED THEIR WAY JUST
ABOVE THE FREEZING MARK. ELSEWHERE...20S ARE THE RULE...EXCEPT ONLY
TEENS ACROSS THE SOUTHERN GREENS AND DACKS.
A POTENT LOOKING UPPER AIR SYSTEM IS EVIDENT ON THE H20 VAPOR
LOOP...WORKING ACROSS NORTHERN NEW YORK STATE. PWATS WITH THIS
FEATURE ARE ONLY AROUND 0.1 INCHES WITH NO REAL MOISTURE SOURCE.
NEVERTHELESS...COOLING CLOUD TOPS BEING NOTED ON ITS NORTHSIDE
ACROSS EASTERN CANADA IN THE AREA OF INCREASING DEFORMATION. THIS
FEATURE WILL SETUP A TROWAL LIKE FEATURE...HOOKING UP WITH THE
REMNANTS OF THE HISTORICAL SNOWSTORM...STILL LURKING OFF THE
CANADIAN MARITIMES. THIS WILL RESULT IN AN INCREASE IN SNOW SHOWER
ACTIVITY ACROSS THE ADIRONDACKS LATER TONIGHT. AS THE UPPER AIR LOW
MOVES SLIPS OFFSHORE...SOME OF THESE SNOW SHOWERS COULD APPROACH THE
CAPITAL REGION TOWARD DAWN.
THE PRESSURE GRADIENT BETWEEN LOW PRESSURE TO OUR NORTHEAST AND HUGE
HIGH PRESSURE RIDGING FROM CANADA ACROSS JAMES BAY...WILL CONTINUE
TO PRODUCE A BITING BREEZE THROUGH THE NIGHT...EXCEPT THOSE
SHELTERED MOUNTAIN VALLEYS.
HENCE... IT WILL BE ANOTHER COLD ONE TONIGHT...BUT NOT UNUSUALLY
COLD FOR THIS LATE IN DECEMBER. EXPECT OVERNIGHT LOWS TO BE MAINLY
IN THE TEENS...EXCEPT 0-10 NORTH. THE CLOUDS AND A BIT OF BREEZE
NORTHWEST 5 TO 15 MPH...SHOULD KEEP READINGS ESPECIALLY SLIGHTLY
HIGHER THAN LAST NIGHT. A BLEND OF THE MET/MAV ACCEPTED.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/...
BY WEDNESDAY MORNING...ISOLATED TO SCATTERED SNOW SHOWERS LOOK TO
PIVOT SOUTHWARD INTO THE CAPITAL REGION AND EVEN POINTS SOUTH. ANY
ACCUMULATION SNOW (AND THAT SHOULD BE LIGHT...AROUND AN INCH OR
LESS) WILL BE CONFINED TO THE MOUNTAIN AREAS...MAINLY NORTH OF
ALBANY. THERE WILL BE MORE CLOUDS THAN SUNSHINE. H850 TEMPERATURES
WILL RANGE FROM -15C TO -17C ACROSS OUR REGION SO TEMPERATURES WILL
REMAIN BELOW FREEZING EVERYWHERE..EVEN TO OUR SOUTH. WENT WITH
COLDER MET NOS WHICH HAS HIGH TEMPERATURES AROUND 20 TO OUR
NORTH...TO AROUND 30 IN OUR SOUTHERN ZONES.
LINGERING CLOUDS AND SNOW SHOWERS WILL BE CONFINED TO THE MOUNTAINS
BY WEDNESDAY NIGHT WITH LITTLE IF ANY ADDITIONAL ACCUMULATION. WITH
H850 TEMPERATURES ACTUALLY WARMING SEVERAL DEGREES DUE TO THE MEAN
FLOW BRINGING MARITIME AIR IN FROM OUR NORTHEAST...LOW TEMPERATURES
WILL NOT BE QUITE AS COLD WITH LOWS AROUND 5 DEGREES TO OUR
NORTH...15 TO AROUND THE SOUTH.
BY THURSDAY...HIGH PRESSURE WILL BUILD NEARLY OVERHEAD ACROSS THE
REGION. THE GRADIENT WILL RELAX A LITTLE AND OUR FLOW WILL BE VERY
ANTICYLONIC...NOT CONDUCIVE TO ANY LAKE EFFECT. TEMPERATURES WILL
MODERATE BACK TO SEASONABLE LEVELS WHICH RANGE FROM THE UPPER 20S
FAR NORTH AND MOUNTAIN AREAS...TO MID 30S TO OUR SOUTH. WITH LESS
WIND...NOT AS COLD TEMPERATURES AND A CONSIDERABLE AMOUNT OF
SUNSHINE IT WILL BE MORE BEARABLE TO BE OUTDOORS...EVEN FOR AN
EXTENDED TIME.
AS WE ROLL INTO THE HOLIDAY TIME...IT NOW APPEARS IT WILL REMAIN DRY
THROUGH MUCH IF NOT ALL OF FRIDAY. IT WILL BE DRY AND PARTLY CLEAR
FOR ALL HOLIDAY SERVICE THURSDAY NIGHT AS LOW TEMPERATURES DROP TO
BETWEEN 10 AND 20 DEGREES...WITH THE COLDEST READINGS IN OUR STILL
SNOW COVERED ADIRONDACKS AND SOUTHERN GREENS. FRIDAY TEMPERATURES
WILL TOP OUT IN THE 30S.
IT NOW APPEARS...THAT THE NEXT SIGNIFICANT STORM...WHICH WILL BE
WORKING INTO THE NORTHWEST US...WILL BE APPROACHING OUR REGION FROM
THE WEST ON FRIDAY NIGHT. BY THIS TIME...THE STRONG RIDGE THAT HAD
BEEN LOCATED OVER GREENLAND...IS FORECAST BY BOTH THE GFS AND
EUROPEAN TO RETROGRADE EASTWARD AND BUILD BACK INTO EASTERN CANADA.
THIS WILL INSURE THAT THE IMPENDING STORM WILL BE FORECAST TO OUR
WEST.
HOWEVER...WITH ENOUGH COLD AIR IN PLACE NEAR THE SURFACE...A
SECONDARY LOW WILL FORM ALONG THE TRIPLE POINT TO OUR SOUTHWEST.
THIS SECONDARY STORM THOUGH LOOKS TO TRACK INLAND ALONG THE I-95
CORRIDOR WHICH WOULD MEAN WHILE IT MIGHT PINCH WARM AIR FROM
REACHING OUR AREA...WARMING ALOFT WILL BE UNINHIBITED. THE PRIMARY
WILL TRACK WELL TO OUR NORTHWEST INTO THE GREAT LAKES REGION.
THERE ARE STILL TIMING ISSUES BETWEEN THE 12Z GFS VERSUS THE 12Z
ECMWF WITH THE LATTER STILL SLOWER (BY ABOUT 12 HOURS) AND WARMER.
THE ECMWF IS GENERALLY A BETTER LONG RANGE FORECASTING MODEL BUT THE
DIFFERENCES IN THIS CASE ARE NOT THAT LARGE FOR BEING FOUR DAYS
OUT.
FOR NOW...WENT WITH A COMPROMISE BETWEEN THE TWO WHICH WOULD BRING
PRECIPITATION INTO OUR REGION BY 12Z SATURDAY AND CONTINUE INTO
SATURDAY NIGHT. MODEL SOUNDINGS OFF THE GFS ARE SUSPECT IN THAT THEY
ARE ACTUALLY DRY INTO LATE SATURDAY. WITH THIS TYPE OF
SETUP...P-TYPES USUALLY BECOMES AN ISSUE. INTERESTING...THE 15Z MREF
PLUMES INDICATE VERY LITTLE FREEZING RAIN FOR ALBANY...NOT MUCH MORE
SLEET...AND MOSTLY RAIN.
STILL...WE DO THINK THE PRECIPITATION WILL START AS SNOW OR SLEET BY
12Z SATURDAY...THEN QUICKLY TRANSITION TO RAIN OR FREEZING RAIN FROM
ALBANY SOUTH. UP NORTH...THE TRANSITION MIGHT MIGHT TAKE A BIT
LONGER. BASED ON THE ORIENTATION OF THE RETREATING SURFACE
HIGH...ORIENTATED NORTH SOUTH AND WELL NORTHEAST...THIS DOES NOT
LOOK LIKE A CLASSIC ICING EVENT BY ANY MEANS. ANY FREEZING RAIN FROM
ALBANY SOUTH LOOKS TO BE BRIEF...BUT IT COULD BE A LITTLE MORE
PROLONGED AT PLACES LIKE GLENS FALLS.
A WARM TONGUE WILL LIKELY CHANGE EVERYONE TO RAIN...AT LEAST BRIEFLY
BY LATE SATURDAY. THEN...COLDER AIR WILL WORK BACK IN FROM THE WEST
SATURDAY NIGHT...TURNING PRECIPITATION BACK TO A MIX OR SNOW.
OBVIOUSLY...THERE IS STILL A LOT OF UNCERTAINTY WITH P-TYPES AND
EVEN AMOUNTS. THE EUROPEAN IS A LITTLE WETTER THAN THE 12Z GFS. THE
15Z MREFS GIVE NEARLY AN INCH TO ALBANY. WILL CONTINUE TO ADDRESS
CONCERNS IN THE HWO.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
MOS GUIDANCE WORKS WELL TODAY WITH TEMPERATURES...AND REASONABLE
TIMING WITH THE DEPARTING CHRISTMAS WEEKEND STORM...WHICH BEGINS
LIFTING OUT OF OUR AREA SUNDAY... AND A BROAD...COLD WESTERLY WIND
FLOW PATTERN SETS UP. THIS WILL RESULT IN FAIRLY WIDESPREAD LAKE
ENHANCED WRAPAROUND SNOW SHOWERS AND FLURRIES. BECAUSE OF THIS...WE
KEEP CHANCE POPS ACROSS THE ENTIRE FORECAST AREA THROUGH MONDAY.
THEREAFTER...THE LAKE EFFECT CONTINUES FOR THE WESTERN ADIRONDACKS.
AMOUNTS WILL BE GENERALLY LIGHT...WITH THE GFS GIVING LITTLE MORE
THAN A COUPLE HUNDREDTHS OF AN INCH THROUGH MONDAY...MORE THAN THAT
IN THE WESTERN ADIRONDACKS...WHERE AS MUCH AS A QUARTER INCH IS
POSSIBLE THROUGH TUESDAY. GIVEN THE TYPICAL FLUFF FACTOR WITH LAKE
EFFECT...THIS COULD MEAN SIGNIFICANT ACCUMULATIONS IN THE WESTERN
ADIRONDACKS...ACCOMPANIED BY ADDED DRIFTING.
DAYTIME HIGH TEMPERATURES WILL BE MOSTLY IN THE 30S SUNDAY...COOLING
A FEW DEGREES EACH DAY. OVERNIGHT LOWS MOSTLY IN THE TEENS AND
LOWER 20S SUNDAY NIGHT WILL BE MAINLY IN THE SINGLE DIGITS AND TEENS
FOR THE BALANCE OF THE WEEK.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
VFR CONDITIONS WILL CONTINUE THROUGH THE ENTIRE TAF PERIOD. SKC WILL
DOMINATE THE AFTN HOURS AT ALL TERMINALS. WINDS WILL REMAIN GUSTY AT
KALB AS AIR FUNNELS DOWN THE MOHAWK VALLEY WITH GUSTS TO 25
KTS...BUT KPOU/KGFL WILL BE SHELTERED ENOUGH FOR LIGHTER WINDS
/GENERALLY LESS THAN 10 KTS/.
A SLOW MOVING CUTOFF UPPER LEVEL LOW SITUATED OVER NEW ENGLAND MAY
BEGIN TO SPREAD SOME SCT STRATO CLOUDS BACK TOWARDS THE AREA TONIGHT
INTO WED MORN...MAINLY FOR KGFL AND KALB...BUT CONDITIONS WILL
REMAIN VFR AND LITTLE IF ANY PRECIP IS EXPECTED. WITH THE LOSS OF
DAYTIME HEATING...WINDS WILL DECREASE AT KALB BACK DOWN TO ABOUT 10
KTS OR SO FOR TONIGHT. WINDS MAY PICK UP AGAIN BY WED MIDDAY AT KALB
AS THE PRESSURE GRADIENT REMAINS TIGHT ENOUGH FOR A FEW GUSTS TO
REACH 20 KTS...BUT WINDS AT OTHER TERMINALS SHOULD REMAIN ABOUT 10
KTS OR LESS.
OUTLOOK...
WED PM-FRI...VFR...NO SIG WX.
FRI NIGHT...VFR/MVFR CIG WITH A CHANCE FOR A WINTRY MIX LATE.
SAT...MVFR-IFR CIG WITH A WINTRY MIX LIKELY CHANGING TO RAIN.
SUN...MVFR...CIG CHC IFR IN RESIDUAL SNOW OR RAIN SHOWERS.
&&
.HYDROLOGY...
NOTE...THE WATERFORD GAGE /WTFN6/ CONTINUE TO EXPERIENCE ICE ON THE
SENSOR AND IS RESULTING IN INACCURATE READINGS AT TIMES. RFC/USGS
AND WATERFORD POLICE DEPARTMENT HAVE BEEN CONTACTED SINCE NO
FLOODING NOR ICE JAMS ARE OCCURRING. THE AHPS WEB PAGE HAS BEEN
NOTATED AT THIS TIME.
THE MONITORING EQUIPMENT ON THE MOHAWK AT LITTLE FALLS HAS ALSO
BECOME FROZEN AND IT IS INOPERATIVE. GAGES ON THE MOOSE RIVER AT
MCKEEVER AND ON THE SCHOHARIE CREEK AT PRATTSVILLE ARE WORKING
BUT READING ABOUT TWO FEET HIGHER DUE TO THE EFFECT OF ICE IN
THE RIVER.
A COLD WEATHER PATTERN WILL CONTINUE ACROSS THE REGION THROUGH
LATE IN THE WEEK. OVER THE NEXT FOUR DAYS...TEMPERATURES ARE
FORECAST TO AVERAGE WELL BELOW FREEZING ACROSS THE ENTIRE FORECAST
AREA. THE COLD TEMPERATURES WILL LIKELY RESULT IN THE FORMATION OF
AN ADDITIONAL SEVERAL INCHES OF ICE ON MANY RIVERS. ACCUMULATING ICE
MAY CAUSE SOME RIVER LEVELS TO RISE EVEN THOUGH FLOWS CONTINUE TO
DIMINISH.
ANY PRECIP THROUGH THURSDAY WILL BE IN THE FORM OF SNOW AND HAVE
NO DIRECT EFFECT ON THE RIVERS...WITH NO MELTING EXPECTED THROUGH
THURSDAY. A MIXED PRECIPITATION EVENT IS POSSIBLE FOR FRIDAY INTO
SATURDAY...STARTING AS SNOW BUT MIXING AND CHANGING TO VARIOUS
FORMS OF WINTRY PRECIP AND EVENTUALLY TO RAIN OVER MUCH OF THE
REGION ON SATURDAY. TEMPERATURES ARE FORECAST TO RISE ABOVE
FREEZING DURING THE DAY THEN DROP BACK BELOW AT NIGHT...SO AT
THIS TIME IT APPEARS THAT LITTLE...IF ANY...MELT AND RUNOFF WILL
OCCUR. BUT IT IS STILL TOO FAR INTO THE FUTURE WITH THIS TYPE OF
STORM TO HAVE A GOOD HANDLE ON PRECIP TYPES AND QPF AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...ELH
AVIATION...FRUGIS
HYDROLOGY...RCK