010
FXUS61 KALY 082317
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
617 PM EST THU DEC 8 2022
SYNOPSIS
CLOUDS GRADUALLY CLEAR TONIGHT GIVING WAY TO A CHILLIER NIGHT.
EXPECT ABUNDANT SUNSHINE TOMORROW WITH SEASONABLY COOL
TEMPERATURES AND A SLIGHT NORTHERLY BREEZE. SUNSHINE ON SATURDAY
WILL SLOWLY FADE BEHIND INCREASING CLOUDS LATE SATURDAY INTO
SATURDAY NIGHT. OUR NEXT DISTURBANCE ARRIVES SUNDAY INTO SUNDAY
NIGHT RESULTING IN A PERIOD OF SNOW AND LIGHT SNOW
ACCUMULATIONS WHICH MAY GIVE US SLIPPERY TRAVEL CONDITIONS.
NEAR TERM /UNTIL 6 AM FRIDAY MORNING/
AS OF 615 PM, FORECAST IS IN GOOD SHAPE WITH NO CHANGES NEEDED.
PREVIOUS DISCUSSION...
CLOUDY SKIES THIS EVENING WILL GRADUALLY GIVE WAY TO CLEARING;
HOWEVER, GUIDANCE STILL SUGGESTS CLOUDS LINGER IN WESTERN NEW
ENGLAND AND INTO PARTS OF THE CAPITAL REGION AND THE EASTERN
CATSKILLS. TEMPERATURES WILL LIKELY BE CONTINGENT ON CLOUD
COVERAGE MEANING WHERE CLOUDS CAN CLEAR OUT (LIKELY
SOUTHERN/WESTERN ADIRONDACKS AND UPPER HUDSON VALLEY)
TEMPERATURES WILL FALL WELL INTO THE 20S AND EVEN UPPER TEENS.
WHERE CLOUDS ARE STUBBORN TO ERODE, TEMPERATURES WILL STAY A BIT
ELEVATED AND MAY ONLY FALL INTO THE MID TO UPPER 20S. ADJUSTED
CLOUD COVERAGE TO BETTER MATCH THE HIGH RESOLUTION GUIDANCE (I.E
HRRR AND NAM) WHICH IS CATCHING ON TO THE FACT THAT CLOUDS MAY
LINGER IN PARTS OF THE REGION. OTHERWISE, NORTHWEST WINDS SHIFT
TO THE NORTH AND DECREASE TO UNDER 5KTS. NORTHERLY FLOW WILL
HELP FUNNEL COOLER AND A MUCH DRIER AIR MASS INTO EASTERN NY AND
WESTERN NEW ENGLAND.
SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/
QUIET AND SEASONABLY COOL TEMPERATURES WILL ENSUE FOR FRIDAY
AND SATURDAY AS HIGH PRESSURE CENTERED NEAR THE HUDSON BAY IN
CANADA STRENGTHENS IMPRESSIVELY TOWARDS 1045 - 1050HPA. DESPITE
THE CENTER OF THE HIGH DISPLACED WELL TO OUR NORTH, IT WILL NOSE
SOUTHWARD INTO THE NORTHEAST. UNDER THE INFLUENCE OF THE HIGH,
EXPECT ABUNDANT SUNSHINE TOMORROW THROUGHOUT THE DAY WITH
NORTHERLY WINDS FUNNELING SEASONABLY COOL AND VERY DRY AIR DOWN
THE NORTH-SOUTH ORIENTED CHAMPLAIN AND HUDSON VALLEY. WITH A
COASTAL LOW OFF THE NEW ENGLAND COAST, THE PRESSURE GRADIENT
OVERHEAD WILL TIGHTEN RESULTING IN SLIGHTLY BREEZY WINDS,
ESPECIALLY DOWN THE VALLEY, RANGING 5 - 10KTS WITH GUSTS UP TO
15-20KTS AT TIMES.
CLEAR SKIES AND NORTHERLY FLOW CONTINUING TO FUNNEL CHILLY AND
VERY DRY AIR DOWN THE VALLEY WILL LIKELY RESULT IN A COLD NIGHT
FRIDAY NIGHT. WE TRENDED TEMPERATURES DOWNWARD COMPARED TO THE
NBM GUIDANCE GIVEN THE CLEAR SKIES AND NORTHERLY FLOW. NORMALLY
CLEAR SKIES AND ANY KIND OF WIND USUALLY IMPEDES TEMPERATURES
FROM COOLING AS MUCH AS THEY COULD BUT IN THIS SITUATION, THE
NORTHERLY WINDS WILL BE ADVECTING IN A CHILLY AIR MASS. THUS, WE
FELT CONFIDENT ENOUGH TO BLEND IN NBM25TH PERCENTILE AND TREND
TEMPERATURES LOWER. DEW POINTS IN THE TEENS AND CLEAR SKIES
WILL ALSO ASSIST COOLING. WE SHOW LOWS REACHING INTO THE MID TO
UPPER TEENS WITH NEAR 20 DEGREES IN THE VALLEY. THE MET/MOS
GUIDANCE ACTUALLY SHOW EVEN COOLER VALUES IN THE LOW TO MID
TEENS BUT WE DID NOT FEEL CONFIDENT TO GO THAT COLD GIVEN THE
SOMEWHAT BREEZY WINDS.
SUNNY SKIES AND CHILLY TEMPERATURES CONTINUE INTO SATURDAY AS
THE ~1045HPA MAINTAINS CONTROL. THE LOW SUBSIDENCE INVERSION
HEIGHT WILL LIKELY LIMIT BOUNDARY LAYER MIXING AND THUS KEEP
HIGH TEMPERATURES SEASONABLY COOL WITH HIGHS IN THE MID TO
UPPER 30S DESPITE THE SUNSHINE. LUCKILY, THE PRESSURE GRADIENT
RELAXES SO NORTHERLY WINDS WILL BE WEAKER COMPARED TO FRIDAY.
CLEAR SKIES SATURDAY NIGHT WILL GRADUALLY FADE BEHIND INTRUDING
CIRRUS CLOUDS FROM SOUTHWEST TO NORTHEAST. TEMPERATURES SHOULD
NOT BE AS COLD AS FRIDAY NIGHT BUT STILL END UP CHILLY FROM
RADIATIONAL COOLING DURING THE FIRST HALF OF THE NIGHT
(ESPECIALLY FOR AREAS NORTH OF I-90 WHERE SKIES STAY CLEAR
LONGER). EXPECT LOWS IN THE LOW TO MID 20S WITH UPPER TEENS IN
THE SOUTHERN ADIRONDACKS WHERE RADIATIONAL COOLING WILL HAVE A
LONGER INFLUENCE.
LONG TERM /SUNDAY THROUGH THURSDAY/
MAIN FOCUS FOR THE LONG TERM IS A SYSTEM THAT WILL BRING A PERIOD OF
LIGHT SNOW TO THE REGION SUNDAY AND SUNDAY NIGHT. THEN, THE FIRST
HALF OF NEXT WEEK LOOS TRANQUIL AND DRY WITH BELOW NORMAL
TEMPERATURES. ANOTHER WEATHER SYSTEM IS POSSIBLE TOWARDS THE END OF
NEXT WEEK, BUT CONFIDENCE IS LOW SURROUNDING THIS SYSTEM. MORE
DETAILS BELOW...
LONG TERM PERIOD BEGINS SUNDAY WITH A STRONG 1040+MB SURFACE HIGH
LOCATED OVER QUEBEC, WITH A SURFACE PRESSURE RIDGE EXTENDING
SOUTHWARDS INTO OUR REGION. AT THE SAME TIME, AN UPER-LEVEL
DISTURBANCE AND ASSOCIATED AREA OF LOW PRESSURE WILL BE TRACKING
ACROSS THE GREAT LAKES SUNDAY AND OVER OUR REGION SUNDAY NIGHT. THIS
CLIPPER SYSTEM SHOULD HAVE ENOUGH MOISTURE AND FORCING FOR ASCENT
(CYCLONIC VORTICITY ADVECTION, LEFT EXIT OF AN UPPER JET STREAK OVER
OUR AREA) TO PRODUCE A LIGHT SNOWFALL FOR MUCH OF THE REGION. IT IS
STILL EARLY TO TALK ABOUT SNOWFALL AMOUNTS, BUT A GENERAL 1-3/2-4"
SNOWFALL SEEMS PLAUSIBLE. SOME RAIN MAY MIX IN IN THE VALLEYS DURING
THE AFTERNOON, BUT ALL AREAS SHOULD SEE A CHANGE TO SNOW BY THE
EVENING, SO EVEN VALLEY AREAS COULD SEE LIGHT SNOWFALL
ACCUMULATIONS. ONSET TIMING OF SNOW LOOKS TO RANGE FROM MID-DAY IN
THE WESTERN MOHAWK VALLEY TO MID TO LATE AFTERNOON IN WESTERN NEW
ENGLAND.
NOW, THERE ARE STILL SOME FORECAST INTRICACIES THAT HAVE TO BE
IRONED OUT. FIRST, AS THE UPPER DISTURBANCE EMERGES OVER THE
ATLANTIC OCEAN SUNDAY NIGHT, THE PRIMARY LOW WILL WEAKEN AND A NEW
SURFACE LOW FORMS OFF THE MID-ATLANTIC COAST. A NORLUN/INVERTED
TROUGH IS EXPECTED TO EXTEND BACK FROM THE COASTAL LOW TOWARDS THE
DECAYING PRIMARY LOW, WHICH WILL BECOME VERTICALLY STACKED BENEATH
THE UPPER LOW. LOCALLY HEAVIER SNOW IS POSSIBLE WITH THIS FEATURE,
BUT WHERE EXACTLY THIS FEATURE SETS UP REMAINS UNCERTAIN, AND THESE
INVERTED TROUGHS OFTEN END UP FURTHER SOUTH THAN MODELED.
ADDITIONALLY, RECENT FORECAST TRENDS HAVE BEEN FOR MORE AMPLIFIED
RIDGING OVER THE CENTER OF THE COUNTRY, WHICH WOULD LEAD TO A
FURTHER NORTH TRACK OF THE SURFACE LOW. THE OTHER FEATURE THAT WILL
NEED TO BE MONITORED IS A CLOSED UPPER LOW DIVING SOUTHWARDS OVER
SOUTHEAST ATLANTIC CANADA ON SUNDAY. IF THIS FEATURE IS
FASTER/FURTHER SOUTH, THEN IT COULD FORCE THE CLIPPER SYSTEM TO
TRACK FURTHER SOUTH, POTENTIALLY LIMITING SNOWFALL ACCUMULATIONS FOR
NORTHERN AREAS. AT THIS TIME, WILL CONTINUE TO MENTION LIGHT
SNOWFALL, WITH A FEW AREAS POTENTIALLY NEEDING WINTER WEATHER
ADVISORIES. HIGHEST CONFIDENCE IN ACCUMULATING SNOW REMAINS FOR
AREAS ALONG AND SOUTH OF I-90.
AS THE SYSTEM PULLS AWAY FROM OUR AREA MONDAY, A RIDGE OF HIGH
PRESSURE BUILDS BACK INTO THE REGION FROM THE NORTH. THIS WILL
RESULT IN COOL BUT TRANQUIL WEATHER FOR THE FIRST HALF OF THE WEEK.
THEN, A MORE IMPRESSIVE STORM SYSTEM MAY APPROACH THE REGION TOWARDS
THE END OF THE WEEK, BUT DUE TO LOW CONFIDENCE WILL JUST MENTION
CHANCES FOR RAIN AND SNOW AT THIS POINT IN TIME.
AVIATION /23Z THURSDAY THROUGH TUESDAY/
THROUGH 00Z SATURDAY...A RIDGE OF HIGH PRESSURE BUILDING OVER THE
REGION FROM THE NORTH WILL RESULT IN DRY AND TRANQUIL WEATHER
THROUGH AT LEAST THE END OF THE TAF PERIOD. FEW TO SCT MID-LEVEL
CLOUDS ARE EXPECTED THROUGH TONIGHT, ESPECIALLY AT GFL AND PSF, BUT
STILL EXPECTING CONDITIONS TO REMAIN VFR. TOMORROW MORNING, ANY MID-
LEVEL CLOUDS DISSIPATE DURING THE MORNING WITH CLEAR SKIES THROUGH
AT LEAST 00Z. WINDS WILL BE AT 5-10 KT FROM THE NORTH/NORTHWEST AT
ALL TAF SITES TONIGHT, THEN WILL BECOME MORE NORTH/NORTHEASTERLY AT
5-10 KT THROUGH THE DAY TOMORROW WHILE REMAINING NORTHWESTERLY AT 5-
10 KT AT PSF.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: MODERATE OPERATIONAL IMPACT. LIKELY SHSN...SN.
SUNDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SHSN.
MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
ALY WATCHES/WARNINGS/ADVISORIES
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
SYNOPSIS...SPECIALE
NEAR TERM...THOMPSON/SPECIALE
SHORT TERM...SPECIALE
LONG TERM...MAIN
AVIATION...MAIN
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