000
FXUS61 KALY 262047
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
347 PM EST WED FEB 26 2014
.SYNOPSIS…
WEAK HIGH PRESSURE WILL BRIEFLY BUILD INTO THE REGION THIS EVENING
INTO THE OVERNIGHT HOURS. ANOTHER CLIPPER WILL BRING A CHANCE OF
MORE SNOW SHOWERS AND SNOW SQUALLS ON THURSDAY WITH SOME BITTERLY
COLD AIR FOR EASTERN NEW YORK AND WESTERN NEW ENGLAND THURSDAY
NIGHT INTO FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/…
AS OF 345 PM EST…CLIPPER TYPE LOW CONTINUES TO MOVE ACROSS SRN
QUEBEC TOWARDS NRN ME AND NEW BRUNSWICK. THE COLD FRONT HAS MOVED
THROUGH WITH SNOW SHOWERS AND FLURRIES. THE MOST CONCENTRATED AREA
OF SNOW AT THIS TIME IS ACROSS THE TUG HILL PLATEAU INTO NORTHERN
AREAS OF HERKIMER COUNTY. AS WE GO INTO THE AFTERNOON HOURS…THE
INLAND EXTENT OF LAKE ONTARIO ORIGIN SNOWBANDS WILL RETREAT CLOSER
TO THE LAKE SHORE AND WITH A WESTERLY FLOW ESTABLISHED…THE BAND
WILL ESTABLISH A 260 TO 270 DEGREE LINE WHICH WILL FAVOR A
NORTHERN HERKIMER COUNTY EVENT. THIS HAS INCREASED OUR CONFIDENCE IN
THE DECISION TO DROP THE LAKE EFFECT SNOW ADVISORY FOR SOUTHERN
HERKIMER COUNTY AT THIS TIME. THE LATEST LOCAL MODEL RUNS AND 3KM
HRRR SHOWS THE LAKE EFFECT BAND OFF OF LAKE ONTARIO TO CONTINUE TO
AFFECT THE WESTERN ADIRONDACKS GOING INTO 00Z THURSDAY. PROJECTED
SNOWFALL TOTALS IN THE MOST PERSISTENT BANDS IN THE LAKE EFFECT
ADVISORY AREA MAY RANGE BETWEEN 3-6 INCHES GOING INTO 00Z
THURSDAY.
TONIGHT….BLUSTERY CONDITIONS WILL PERSIST THROUGH THE EVENING
HOURS AND THE LAKE EFFECT BAND WILL COME TO AN END AS WE WORK OUR
WAY THROUGH THE OVERNIGHT HOURS. A WEAK RIDGE OF HIGH PRESSURE
WILL MOVE EAST OVER THE REGION TEMPORARILY PROVIDING ONLY A SLIGHT
CHANCE OF A SNOW SHOWER IN THE FAR NORTHWESTERN AREAS OF THE CWA.
WINDS WILL BE LIGHT OUT OF THE WEST WHICH WILL GRADUALLY SWITCH TO
SOUTHWESTERLY AS WE GO THROUGH THE OVERNIGHT PERIOD. LOW
TEMPERATURES ACROSS THE REGION WILL BE WELL BELOW NORMAL. LOW
TEMPERATURES WILL RANGE FROM THE SINGLE DIGIT RANGE OF 0 TO 5
ACROSS THE MOHAWK VALLEY AND THE IMMEDIATE CAPITAL REGION ALONG
WITH AREAS SOUTH AND EAST OF THE IMMEDIATE CAPITAL REGION. ACROSS
THE LAKE GEORGE SARATOGA REGION….ADIRONDACKS AND SOUTHERN
VERMONT…LOW TEMPERATURES WILL RANGE FROM 0 TO 7 OR 8 BELOW ZERO
…ESPECIALLY ACROSS THE ADIRONDACKS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/…
THU-THU NIGHT….THE SECOND CLIPPER TYPE SYSTEM IMPACTS THE FA AS
IT MOVES ACROSS SOUTHERN QUEBEC. THIS SECOND CLIPPER SYSTEM
MAGNITUDE WILL BE SLIGHTLY STRONGER THAN THE FIRST ONE…AS A DEEPER
TROUGH AXIS WILL PIVOT AROUND THE MAIN UPPER LEVEL FEATURE ACROSS
WESTERN QUEBEC. CHANCES OF SNOW SHOWERS WILL FIRST OCCUR IN THE
EARLY MORNING HOURS ON THURSDAY. WITH A HIGHER SUN ANGLE
ESTABLISHED AT THIS TIME…SURFACE TO 800 HPA TEMPERATURES GIVEN
THE LATEST MODEL GUIDANCE SOUNDING SHOW GREAT TEMPERATURE
DIFFERENCES. THIS ACCOMPANIED BY DECENT PERTURBATIONS OF OMEGA
VALUES FOR LIFT AND A DEVELOPING NEGATIVE TILTED UPPER LEVEL
TROUGH WITH AN AXIS REACHING SOUTH INTO THE ADIRONDACKS AS WE GO
BETWEEN 18Z AND 00Z FRIDAY…EMBEDDED PERIODS OF SNOW SQUALLS ARE
POSSIBLE DURING THIS TIME FRAME. THE GREATEST PROBABILITIES OCCUR
ACROSS AREAS NORTH OF THE IMMEDIATE CAPITAL REGION AND ACROSS
SOUTHERN VERMONT WHERE SNOWFALL BANDS MAY PRODUCE UP TO HALF AN
INCH PER HOUR IN ISOLATED AREAS. UPPER LEVEL INSTABILITY VALUES
MAY REACH A MAXIMUM IN THE DENDRITIC GROWTH ZONE…AS THE CORE OF
THE UPPER LEVEL ENERGY WILL BE IN OUR NORTHERN AREAS BETWEEN 18Z
THURSDAY AND 00Z FRIDAY AS THE UPPER LEVEL WAVE MOVES ACROSS THE
AREA AT THIS TIME. A TRAILING COLD FRONT BEHIND THE DEPARTING
SURFACE LOW MAY ALSO PROVIDE A BRIEF PERIOD OF MODERATE TO HEAVY
SNOW ACROSS THE BAROCLINIC ZONE ALONG THE FRONT NEAR THE 00Z
FRIDAY HOUR AS IT MOVES WEST TO EAST ACROSS THE REGION. SNOWFALL
AMOUNTS WILL RANGE BETWEEN 1-2 INCHES WITH THE HIGHER AMOUNTS IN
THE MOST PERSISTENT SNOWFALL BANDS OR SNOW SQUALLS. HIGH
TEMPERATURES ON THURSDAY WILL RANGE FROM THE UPPER TEENS IN THE
ADIRONDACKS TO MID 20S IN VALLEY LOCATIONS. WINDS WILL BE ALSO
QUIET BRISK WITH GUSTS TO NEAR 30 MPH AT TIMES…ESPECIALLY IN THE
AFTERNOON HOURS.
THE UPPER LEVEL SHORTWAVE AND FRONTAL SYSTEM WILL EXIT THE REGION
THURSDAY NIGHT. A PASSING SNOW SHOWER CLOSER CONFINED TO THE GREAT
LAKES IS POSSIBLE…BUT IT WILL BE A VERY COLD NIGHT ONCE AGAIN
ACROSS THE REGION. WIND CHILL ADVISORIES MAY NEED TO BE ISSUED AT
A FUTURE UPDATE. LOW TEMPERATURES WILL RANGE FROM 0 TO 5 ABOVE
FROM THE IMMEDIATE CAPITAL REGION POINTS SOUTH AND EAST AND BELOW
ZERO FROM THE LAKE GEORGE SARATOGA REGION POINTS NORTH AND WEST
WITH SOME AREAS IN THE ADIRONDACKS NEAR 10 BELOW ZERO.
FRIDAY AND FRIDAY NIGHT HIGH PRESSURE WILL PROVIDE PLENTY OF
SUNSHINE TO THE REGION ALTHOUGH IT WILL STILL BE VERY COLD AND
BLUSTERY. EXPECT HIGH ON FRIDAY TO BE IN THE TEENS TO AROUND 20
WITH PERHAPS ONLY SINGLE DIGITS ACROSS PORTIONS OF THE WESTERN
ADIRONDACKS. LOWS FRIDAY NIGHT WILL BE IN THE 10 BELOW TO 5 ABOVE
ZERO RANGE ONCE AGAIN.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/…
COMING SOON…
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/…
PREDOMINATELY VFR CONDITIONS WILL PREVAIL THROUGHOUT THE TAF PERIOD
WITH SCATTERED SNOW SHOWERS DIMINISHING BY THIS EVENING.
THIS AFTERNOON…WIDELY SCATTERED SNOW SHOWERS ASSOCIATED WITH A
WEAK CLIPPER AND COLD FRONT WILL CONTINUE THROUGH THE AFTERNOON
HOURS…ESPECIALLY AT KGFL WHERE SOME LAKE MOISTURE WILL ALSO BE
TAPPED. HAVE INCLUDED A TEMPO GROUP AT KGFL UNTIL 20Z TO ACCOUNT FOR
ANY BRIEF IFR REDUCTIONS IN HEAVIER SNOW SHOWERS…AND VCSH AT THE
OTHER TAF SITES DUE TO WIDELY SCATTERED NATURE OF THE SHOWERS.
WESTERLY WINDS WILL BE GUSTY THIS AFTERNOON…GUSTING 20-25 KNOTS
EXCEPT AT KALB AND KPSF WHERE GUSTS AS HIGH AS 35 KNOTS WILL BE
POSSIBLE.
TONIGHT INTO THURSDAY…THE LOSS OF DAYTIME HEATING WILL HELP WINDS
SUBSIDE THIS EVENING ALONG WITH GRADUALLY CLEARING SKIES AS WEAK
HIGH PRESSURE BUILDS ACROSS THE REGION. MID CLOUDS WILL GRADUALLY
BUILD FROM WEST TO EAST ACROSS THE REGION AHEAD OF ANOTHER
APPROACHING CLIPPER SYSTEM WITH VCSH DEVELOPING BY THE END OF THE
TAF PERIOD…ESPECIALLY NORTH AND WEST.
WINDS WILL BE LIGHT AND VARIABLE TONIGHT GENERALLY LESS THAN 8 KNOTS
BEFORE INCREASING AFTER DAYBREAK THURSDAY OUT OF THE SOUTHWEST AT
10-15 KNOTS WITH GUSTS 20-25 KNOTS.
OUTLOOK…
THURSDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY SLIGHT CHANCE OF SHSN.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
&&
.HYDROLOGY…
NO HYDRO IMPACTS ARE EXPECTED ON THE MAIN STEM RIVERS THE NEXT 5
DAYS. AN ARCTIC AIR MASS WILL REMAIN ACROSS THE HYDRO SERVICE AREA
INTO THE WEEKEND…WHICH WILL ALLOW ICE TO REFORM…THICKEN…AND
STRENGTHEN ON AREA RIVERS AND LAKES THROUGH THE WEEK.
LIGHT PRECIPITATION IS EXPECTED INTO THE MAJORITY OF THE WEEKEND…
AND ANY THAT DOES OCCUR WILL BE IN THE FORM OF SNOW SHOWERS OR
LIGHT SNOW FROM CLIPPER LOWS OR LAKE EFFECT.
A SIGNIFICANT STORM SYSTEM MAY BRING HEAVY PCPN MAINLY IN THE FORM
OF SNOWFALL LATE SUNDAY NIGHT INTO MONDAY. THE TRACK WILL MAKE THE
DIFFERENCE IN THE AMOUNT OF QPF.
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 ADVISORY UNTIL 10 PM EST THIS EVENING FOR
NYZ032.
MA…NONE.
VT…NONE.
&&
$$
SYNOPSIS…LFM
NEAR TERM…LFM/NAS/WASULA
SHORT TERM…LFM
LONG TERM…ELH
AVIATION…IRL
HYDROLOGY…LFM/WASULA/11
