Area Forecast Discussion
Issued by NWS Albany, NY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KALY 202033
AFDALY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
333 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL PASS NORTH OF THE REGION THIS WEEKEND...WHILE
WEAK UPPER LEVEL DISTURBANCES PASS SOUTH OF THE REGION. THESE UPPER
LEVEL IMPULSES WILL BRING AREAS OF CLOUDS THROUGH MONDAY...AND
PERHAPS SOME FLURRIES FOR SOUTHEAST AREAS LATE TONIGHT. UNSETTLED
CONDITIONS WILL PERSIST THROUGH MUCH OF THE UPCOMING WEEK...WITH
A PERIOD OF LOCALLY HEAVY RAIN AND STRONG WINDS POSSIBLE WEDNESDAY
INTO WEDNESDAY NIGHT.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 330 PM THIS AFTERNOON...CLOUDS COVERED THE SOUTHWESTERN
HALF OF THE FA WITH MAINLY CLEAR SKIES ACROSS THE NORTHEASTERN
HALF OF THE FA. CLOUDS ARE EXPECTED TO OVERSPREAD THE REMAINDER OF
THE FA THIS EVENING INTO THE OVERNIGHT. A WEAK TROUGH OF LOW
PRESSURE ALONG THE NEW ENGLAND COAST WILL BE THE FOCUSING
MECHANISM FOR SOME LIGHT SNOW TO BACK IN ACROSS THE BERKSHIRES AND
LITCHFIELD HILLS DURING THE SECOND HALF OF THE OVERNIGHT PERIOD.
DUE TO THE CLOUD COVER OVERNIGHT TEMPS ARE NOT EXPECTED TO DROP
AS MUCH AS THEY DID LAST NIGHT. EXPECT LOW TEMPS TO RANGE FROM THE
MID TEENS NORTHWEST TO MID 20S SOUTHEAST.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
ANY LINGERING SNOW WILL END ACROSS THE BERKSHIRES AND LITCHFIELD
HILLS BY MID DAY SUNDAY. ACCUMULATIONS LOOK TO BE VERY LIGHT WITH
A FEW TENTHS OF AN INCH UP TO AN INCH TOTAL. THE REMAINDER OF THE
DAY IS EXPECTED TO BE CLOUDY ACROSS THE FA AS LOW LEVEL INVERSIONS
REMAIN IN PLACE TRAPPING MOISTURE BENEATH THEM. HIGHS ON SUNDAY
ARE EXPECTED TO RANGE FROM THE UPPER 20S NORTHWEST TO THE MID 30S
SOUTHEAST.

SUNDAY NIGHT AND MONDAY...MOSTLY CLOUDY CONDITIONS WILL CONTINUE
AS MOISTURE STARTS TO LIFT NORTHWARD FROM THE MID ATLANTIC REGION
ON MONDAY AHEAD OF A SURFACE LOW LIFTING NORTHEASTWARD ALONG THE
EASTERN SEABOARD. WHILE IT WILL BE DRY...CLOUDS WILL BE FAIRLY
WIDESPREAD WITH LOWS SUNDAY NIGHT IN THE MID TEENS TO MID 20S AND
HIGHS ON MONDAY IN THE 30S.

ON MONDAY NIGHT MOISTURE STARTS TO OVERSPREAD THE FORECAST AREA AS
THE LOW PRESSURE SYSTEM IS LOCATED OFF THE DELMARVA PENINSULA WITH
A TROUGH OF LOW PRESSURE ALONG THE SOUTHERN NEW ENGLAND COAST.
WEAK ISENTROPIC LIFT IS EXPECTED ACROSS THE FA WITH A PLETHORA OF
PCPN TYPES MONDAY NIGHT ACROSS THE SOUTHERN HALF OF THE FA WITH
MAINLY SNOW ACROSS THE NORTHERN HALF OF THE FA. PCPN SHOULD START
AS SNOW IN ALL AREAS BEFORE THE TRANSITION OCCURS DURING THE
SECOND HALF OF THE NIGHT ACROSS THE SOUTHERN HALF OF THE FA.
PARTIAL THICKNESS VALUES AND MODEL SOUNDINGS SUPPORT SOME LIGHT
FREEZING RAIN AND SLEET MIXING IN ACROSS THE SOUTHERN HALF OF THE
FA. LOWS MONDAY NIGHT WILL BE TRICKY WITH NOT MUCH OF A DROP FROM
DAYTIME HIGHS ON MONDAY. EXPECT LOWS MONDAY NIGHT TO BE IN THE MID
20S TO LOWER 30S.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
UNSETTLED WEATHER WILL BE THE RULE THROUGH AT LEAST WEDNESDAY
NIGHT...PUNCTUATED BY A STRONG STORM SYSTEM TRACKING INTO THE GREAT
LAKES FOR WEDNESDAY AND WEDNESDAY NIGHT. AHEAD OF THE MAIN STORM
SYSTEM...A PERSISTENT MOIST FLOW FROM THE ATLANTIC AND OVERRUNNING
WILL ALLOW FOR WIDESPREAD CLOUDS AND LIGHT PRECIPITATION TUE AND TUE
NT. A SURGE OF ISENTROPIC LIFT AHEAD OF A LEAD UPPER LEVEL IMPULSE
SHOULD ALLOW FOR A GREATER AREAL COVERAGE OF LIGHT PRECIPITATION FOR
TUESDAY...ESP IN THE MORNING. THERMAL PROFILES SUGGEST THAT THE
ONSET OF PRECIPITATION WOULD BE LIGHT SNOW OR A LIGHT WINTRY MIX OF
SNOW...SLEET AND FREEZING RAIN TUESDAY MORNING...BEFORE
TRANSITIONING TO MAINLY LIGHT RAIN OR DRIZZLE BY LATE TUESDAY IN
MOST AREAS. THERE IS A POSSIBILITY THAT SOME POCKETS OF FREEZING
RAIN OR FREEZING DRIZZLE COULD LINGER INTO LATE TUE OR TUE EVE
ACROSS SOME SHELTERED VALLEYS OF THE LAKE GEORGE REGION AND SOUTHERN
VT...AND POSSIBLY EASTERN BERKSHIRE CO. EXPECT TEMPS TO SLOWLY RISE
INTO THE MID AND UPPER 30S BY LATE TUESDAY. FOR TUE NT...MOST TEMPS
SHOULD HOLD NEARLY STEADY IN THE 30S.

THE MAIN STORM SHOULD IMPACT THE REGION WED INTO WED NT...ALTHOUGH
TIMING DIFFERENCES REMAIN IN THE LONG TERM GUIDANCE...AND THE
HANDLING OF POTENTIAL SFC WAVE DEVELOPMENT ALONG A COLD/OCCLUDED
FRONT APPROACHING FROM THE SOUTHWEST. A NARROW COLD FRONTAL RAIN BAND
WILL LIKELY IMMEDIATELY PRECEDE/ACCOMPANY THE FRONT...AND COULD EVEN
CONTAIN SOME RUMBLES OF THUNDER. MOST LONG TERM GUIDANCE SUGGESTS
THAT THIS FRONT PASSES THROUGH BETWEEN 00Z-06Z/THU. THE 12Z/20 ECMWF
SEEMS TO BE MOST AGGRESSIVE WITH WAVE DEVELOPMENT ALONG THE
BOUNDARY. IN FACT...IT ACTUALLY ALLOWS COLDER AIR TO MOVE INTO
PORTIONS OF THE REGION AS THE TRAILING STRATIFORM PORTION OF THE
NARROW COLD FRONTAL BAND PASSES THROUGH...WITH SOME SUGGESTION OF
PRECIP ENDING AS SNOW...AT LEAST ACROSS HIGHER ELEVATIONS. THE
GFS/GEFS ARE MORE PROGRESSIVE AND LESS EMPHATIC WITH WAVE
DEVELOPMENT AND ANY SNOW/MIXED PRECIP. AT THIS TIME...HAVE INDICATED
SOME TRANSITION LATE AT NIGHT TO RAIN/SNOW SHOWERS IN VALLEYS...AND
MAINLY SNOW SHOWERS ACROSS HIGHER ELEVATIONS.

RAINFALL COULD BE LOCALLY HEAVY WED-WED NT...WITH TOTAL QPF RANGING
FROM 0.75-1.5 INCHES...ALTHOUGH HIGHER AMTS WOULD BE POSSIBLE...ESP
SHOULD ANY WAVE DEVELOP ALONG THE BOUNDARY AND SLOW DOWN THE FORWARD
MOTION OF ANY FRONTAL RAIN BAND. THIS HEAVY RAINFALL...COMBINED WITH
SNOWMELT DUE TO STRONG WINDS AND MILD TEMPERATURES/HIGH
DEWPOINTS...COULD LEAD TO SOME HYDROLOGIC ISSUES INCLUDING MINOR
FLOODING. SEE THE HYDROLOGIC DISCUSSION FOR MORE DETAILS.

WINDS WILL ALSO BE QUITE STRONG ACROSS HIGHER ELEVATIONS OF THE
ADIRONDACKS/CATSKILLS...AND WESTERN NEW ENGLAND...WHERE GUSTS OF
30-40 MPH WILL BE POSSIBLE...WITH SOME POTENTIAL FOR EVEN HIGHER
GUSTS. IN VALLEYS...BOUNDARY LAYER STABILITY MAY LIMIT HOW MUCH WIND
REACHES THE SURFACE...BUT WILL CERTAINLY NEED TO ASSESS THIS CLOSER
TO THE EVENT. SOME STRONGER GUSTS COULD ALSO OCCUR WITHIN ANY TALLER
CONVECTIVE ELEMENTS AHEAD OF AND WITH THE ACTUAL FRONT AS WELL. MAX
TEMPS ON WED WILL BE TRICKY...AS THERE IS A POSSIBILITY THAT RAPID
WARMING WELL INTO THE 50S COULD OCCUR AS A WARM FRONT TRANSLATES
NORTHWARD. THIS POTENTIAL WILL BE GREATEST ACROSS THE MID HUDSON
VALLEY AND NW CT. FOR WED NT/THU AM...TEMPS SHOULD EVENTUALLY FALL
BACK INTO THE 30S IN VALLEYS...AND POSSIBLY SOME UPPER 20S ACROSS
HIGHER ELEVATIONS.

IN THE WAKE OF THE MAIN STORM SYSTEM...WINDY AND MOSTLY CLOUDY
CONDITIONS SHOULD PREVAIL FOR THURSDAY...WITH SNOW SHOWERS PREVALENT
ACROSS HIGHER ELEVATIONS AND AREAS NEAR AND NORTH OF INTERSTATE 90.
WILL NEED TO WATCH FOR LAKE ENHANCEMENT ACROSS PORTIONS OF THE
WESTERN ADIRONDACKS AS WELL. TEMPS WILL GENERALLY REMAIN ABOVE
NORMAL...WITH DAYTIME MAXES REACHING THE 30S TO LOWER 40S.

RISING HEIGHTS IN THE WAKE OF THE STORM SHOULD ALLOW FOR A
DECREASING TREND IN AREAL COVERAGE OF SNOW SHOWERS FOR THU NT AND
ESP FRI. THU NT/FRI AM MIN TEMPS SHOULD FALL INTO THE 20S TO AROUND
30...WITH MAX TEMPS FRI MAINLY IN THE LOWER 40S IN VALLEYS AND 30S
ACROSS HIGHER ELEVATIONS...AND OVERNIGHT MINS FOR FRI NT/SAT AM
FALLING INTO THE 20S AND LOWER 30S. AND ANOTHER STORM SYSTEM COULD
BRING SOME RAIN OR SNOW TO THE REGION BY NEXT WEEKEND...WITH MAX
TEMPS REACHING 35-40 IN VALLEYS...AND LOWER/MID 30S ACROSS HIGHER
ELEVATIONS.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL PASS NORTH OF THE REGION THROUGH EARLY SUNDAY.
AN UPPER LEVEL DISTURBANCE WILL PASS JUST SOUTH OF THE REGION
LATER TONIGHT INTO SUNDAY MORNING. THE COMBINATION OF LOW LEVEL
MOISTURE BEING DRAWN NORTHWEST FROM THE ATLANTIC OCEAN...AND WEAK
DYNAMICS FROM THE DISTURBANCE PASSING TO OUR SOUTH....MAY BRING
SOME VERY LIGHT SNOW OR FLURRIES TO SOME OF THE TAF SITES LATER
TONIGHT INTO SUNDAY MORNING.

OVERALL FLIGHT CONDITIONS SHOULD TREND TO VFR THIS AFTERNOON WITH
THE EXCEPTION OF KPSF...WHERE MVFR CIGS SHOULD CONTINUE. VFR LEVEL
CIGS SHOULD GRADUALLY LOWER INTO THE MVFR RANGE LATER
TONIGHT...AND PERSIST THROUGH MIDDAY SUNDAY.

THE CHANCE FOR SOME VERY LIGHT SNOW OR FLURRIES WILL INCREASE
LATER TONIGHT...MAINLY FOR KPSF/KPOU...WITH TIMING OF POSSIBLE
DEVELOPMENT MAINLY AFTER 08Z-10Z/SUN AND LINGERING UNTIL AT LEAST
14Z-16Z/SUNDAY. A PERIOD OF MVFR/IFR CIGS AND VSBYS WILL BE
POSSIBLE DURING THESE TIMES. IT IS MORE UNCERTAIN WHETHER ANY
LIGHT SNOW WILL REACH KALB AND KGFL. FOR NOW...HAVE INDICATED
A CHANCE AT KALB...BUT RADAR TRENDS WILL NEED TO BE WATCHED
OVERNIGHT IN CASE THE AREAL EXPANSION OF ANY LIGHT SNOW/FLURRIES
REACHES FURTHER N.

WINDS WILL BE MAINLY FROM THE N TO NE AT GENERALLY 5-10 KT THIS
AFTERNOON...TRENDING TO LIGHT AND VARIABLE TONIGHT INTO SUNDAY
MORNING.

OUTLOOK...
SUNDAY NIGHT AND MONDAY: NO OPERATIONAL IMPACT.  NO SIG WX.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN...SLEET...DZ.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
TUESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA.
WEDNESDAY: HIGH OPERATIONAL IMPACT.BREEZY DEFINITE RA.
WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE SHRA...RA.
CHRISTMAS DAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.

&&

.HYDROLOGY...
NO HYDROLOGIC ISSUES ARE ANTICIPATED THROUGH TUESDAY NIGHT. A
WIDESPREAD RAINFALL IS EXPECTED WEDNESDAY INTO WEDNESDAY NIGHT AS
A LARGE LOW PRESSURE SYSTEM MOVES ACROSS THE REGION. RAINFALL
AMOUNTS OF 0.75 INCH TO 1.5 INCHES ARE LIKELY ALONG WITH
SIGNIFICANT SNOWMELT WHICH RAISES THE POTENTIAL FOR MINOR FLOODING
AND SIGNIFICANT WITHIN BANK RISES OF LARGER STEM RIVERS. MMEFS
GUIDANCE POINTS TO MANY POINTS AT LEAST REACHING ACTION STAGE
AND HAS GVVN6 HAVING A HIGH PROBABILITY FROM THE GEFS AND NAEFS
GUIDANCE OF REACHING MINOR FLOOD STAGE ON CHRISTMAS DAY. TOO EARLY
TO ISSUE ANY FLOOD WATCHES...HOWEVER WILL MENTION IN THE HWO AT
THIS TIME.

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...KL
NEAR TERM...11
SHORT TERM...11
LONG TERM...KL
AVIATION...KL
HYDROLOGY...11






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.