859
FXUS61 KALY 021849
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
249 PM EDT WED SEP 2 2026
WHAT HAS CHANGED
LOWERED TEMPERATURES AND DEW POINTS THIS AFTERNOON, AND INCREASED
POPS THROUGH THE NEXT FEW HOURS FOR AREAS SOUTH OF I-90 AS REMNANT
SHOWERS FROM THE MORNING MCS SHOULD CONTINUE TO WEAKEN AS THEY TRACK
EASTWARDS. SEVERE WEATHER AND FLASH FLOODING REMAIN POSSIBLE TONIGHT
WITH ANOTHER EXPECTED MCS.
KEY MESSAGES
1) SCATTERED SHOWERS AND A FEW NON-SEVERE THUNDERSTORMS ARE EXPECTED
ACROSS SOUTHERN AREAS THIS AFTERNOON. THEN, MORE NUMEROUS
SHOWERS AND STORMS ARE EXPECTED THIS EVENING INTO TONIGHT WITH
STRONG WINDS, LARGE HAIL, AND HEAVY RAIN LEADING TO FLASH
FLOODING ALL POSSIBLE.
3) GENERALLY TRANQUIL WEATHER WITH NEAR TO SLIGHTLY BELOW NORMAL
TEMPERATURES EXPECTED FRIDAY INTO EARLY NEXT WEEK.
DISCUSSION
KEY MESSAGE 1...AS OF 2:50 PM EDT...AN AREA OF SHOWERS THAT ARE
REMNANTS OF AN EARLY MORNING MCS THAT MOVED ACROSS WESTERN NY
ARE CURRENTLY TRACKING ACROSS OUR REGION SOUTH OF I-90. THESE
SHOWERS HAVE SUSTAINED THEMSELVES A LITTLE LONGER THAN
PREVIOUSLY THOUGHT LIKELY DUE TO MULTIPLE MCVS THAT HELPED TO
LOCALLY INCREASE LIFT. HOWEVER, CURRENT MESOANALYSIS SHOWS A
VERY TIGHT INSTABILITY GRADIENT NEAR OUR WESTERN BORDER WITH
BGM, SO THEY SHOULD CONTINUE TO WEAKEN THE FURTHER EAST THEY
TRACK. SO, NO SEVERE WEATHER OR FLOODING EXPECTED THROUGH THE
FEW HOURS. MOST OF OUR REGION IS ACTUALLY IN A COLD AIR DAMMING
SETUP THANKS TO SFC HIGH PRESSURE LOCATED OVER SOUTHEASTERN
CANADA. WE LOWERED TEMPS AND DEW POINTS SEVERAL DEGREES FROM THE
NBM, WITH AFTERNOON HIGHS EXPECTED TO BE MAINLY IN THE 60S
(TERRAIN) TO LOW 70S (VALLEYS).
FOR THIS EVENING AND TONIGHT: GOES 16 WV IMAGERY SHOWS A STRONG
COSED UPPER LOW NEAR JAMES BAY, WITH A CLOSER UPPER RIDGE CENTERED
OVER TENNESSEE. BETWEEN THESE FEATURES, AN UPPER IMPULSE EMBEDDED IN
THE FAST FLOW ALOFT WILL TRACK OVER THE GREAT LAKES AND NORTHEAST
THIS EVENING INTO TONIGHT. CURRENT RADAR ALREADY SHOWS STORMS FIRING
OVER SOUTHERN ONTARIO WITH THIS FEATURE, AND THESE ARE EXPECTED TO
GROW UPSCALE INTO AN MCS THIS AFTERNOON/EVENING BEFORE TRACKING INTO
OUR AREA.
A N/S ORIENTED WARM FRONT IS CURRENTLY LOCATED OVER CENTRAL NY,
SEPARATING A VERY MOIST AND UNSTABLE AIRMASS FROM A MUCH COOLER AND
MORE STABLE AIRMASS. HOW FAR EAST THIS FRONT IS ABLE TO MAKE IT THIS
EVENING WILL DETERMINE HOW FAR EAST THE THREAT FOR SEVERE WEATHER
WILL EXTEND. OUTFLOW FROM THE AM CONVECTION SEEMS TO HAVE REINFORCED
THE COOL SIDE OF THE BOUNDARY/PUSHED IT BACK WEST DOWN TOWARDS THE
CATSKILLS AND SOUTHERN TIER. HOWEVER, CURRENT SATELLITE IMAGERY
SHOWS QUITE A BIT OF CLEARING AND INSTABILITY BEGINNING TO
BUILD WEST OF OUR MOHAWK VALLEY AND VERY CLOSE TO OUR ADKS. IF
THE WARM FRONT AND INSTABILITY ARE ABLE TO PUSH CLOSER/INTO THE
ADKS AND WESTERN MOHAWK VALLEY, THIS WOULD INCREASE THE SEVERE
THREAT FOR THESE AREAS THIS EVENING. FURTHER EAST, GUIDANCE IS
IN GOOD AGREEMENT FOR STEEPENING MID-LEVEL LAPSE RATES
ASSOCIATED WITH A WEAK EML PLUME TO ALLOW FOR SOME ELEVATED
INSTABILITY TO WORK ITS WAY INTO OUR AREA, ALTHOUGH SBCAPE LOOKS
TO BE VERY LIMITED. GIVEN EXPECTED SHARP INSTABILITY GRADIENT,
THERE REMAINS SOME UNCERTAINTY IN JUST HOW FAR EAST THE SEVERE
THREAT WILL EXTEND. SPC HAS LEFT THEIR D1 CONVECTIVE OUTLOOK
ACROSS OUR REGION UNCHANGED, WITH THE MARGINAL RISK MAINLY JUST
FOR OUR WESTERN AREAS. HOWEVER, GIVEN CURRENT SATELLITE AND
MESOANALYSIS TRENDS, WE CAN'T RULE OUT A FEW STRONGER STORMS AS
FAR EAST AS THE HUDSON VALLEY OR EVEN TACONICS THIS
EVENING/TONIGHT. MAIN THREATS WOULD BE DAMAGING WINDS WITH THE
MCS THAT IS EXPECTED TO DEVELOP, BUT LARGE HAIL ALSO VERY MUCH
REMAINS ON THE TABLE GIVEN THE PRESENCE OF ELEVATED INSTABILITY,
VERY FAVORABLE SHEAR PROFILES (LONG STRAIGHT HODOGRAPHS), AND
ELEVATED CONVECTION TRACKING ON THE COOL SIDE OF THE SFC
BOUNDARY. CLOSER TO THE BOUNDARY ITSELF IN WESTERN HERKIMER
COUNTY, THERE LOOKS TO BE MORE HELICITY (>200 M2S2 0-1 KM
LAYER), SO AN ISOLATED TORNADO CAN'T TOTALLY BE RULED OUT
ALTHOUGH THE PROBABILITY IS RELATIVELY LOW.
OTHER THREAT THIS EVENING/TONIGHT WITH THE MCS WILL BE FOR HEAVY
RAIN LEADING TO FLASH FLOODING. THERE WAS SOME CONSIDERATION TO
ISSUING A FLOOD WATCH FOR THE WESTERN MOHAWK VALLEY AND EASTERN
CATSKILLS ALONG OUR BORDER WITH BGM, BUT OPTED NOT TO AS THE HEAVIER
RAIN THIS MORNING LEADING TO MORE PRIMED SOILS REMAINED MAINLY WEST
US. OUR CWA ONLY SAW 0.1 TO 0.25 INCHES PER THE NYS MESONET, AND THE
AREAS THAT DID SEE RAIN (MAINLY CATSKILLS) ALSO MISSED SOME OF THE
HEAVIER RAIN OVER THE LAST COUPLE DAYS. NEVERTHELESS, THE
ENVIRONMENT LOOKS FAVORABLE FOR HEAVY RAIN THIS EVENING AND TONIGHT
WITH PWATS EXPECTED TO 1.7 - 1.9" AND WARM CLOUD DEPTHS >12 KFT.
RAINFALL RATES OF 1-2" PER HOUR WILL BE POSSIBLE WITH THE MCS. MAIN
CONCERNS WOULD BE ON THE SOUTHERN SIDE WHERE MORE BACKBUILDING AND
TRAINING IS POSSIBLE. WHERE TRAINING OCCURS, ISOLATED 2-3" RAINFALL
AMOUNTS CAN'T BE RULED OUT. WPC HAS MAINTAINED THEIR MARGINAL TO
SLIGHT RISK ERO FOR OUR REGION, SO WILL MENTION ISOLATED TO MAYBE
SCATTERED INSTANCES OF FLASH FLOODING ARE POSSIBLE, BUT JUST NOT
WIDESPREAD ENOUGH TO JUSTIFY A FLOOD WATCH AT THIS TIME.
TIMING OF THIS MCS HAS SPED UP SLIGHTLY COMPARED TO YESTERDAY'S
FORECAST, SO IT SHOULD LARGELY BE OUT OF OUR AREA BY OR AROUND 12Z
THURSDAY. THE WARM FRONT MAY LIFT BACK NORTH INTO THE MID HUDSON
VALLEY TOMORROW, WITH UP TO 1000-2000 J/KG OF SBCAPE EXPECTED TO
BUILD SOUTH OF I-90. DEEP LAYER SHEAR REMAINS IMPRESSIVE AT 35-45
KT, SO ON PAPER THE ENVIRONMENT APPEARS FAVORABLE FOR A FEW STRONG
STORMS. HOWEVER, THERE REMAINS A SIGNAL FOR FAIRLY STRONG MID-LEVEL
SUBSIDENCE AND DRYING IN THE WAKE OF THE UPPER SHORTWAVE TOMORROW
AFTERNOON ACROSS OUR REGION. THE SUBSIDENCE WILL ALSO HELP REINFORCE
A CAPPING INVERSION, AND ALL OF THIS MAY MAKE IT VERY HARD FOR
STORMS TO TAKE ADVANTAGE OF THIS FAVORABLE ENVIRONMENT. SO, SEVERE
THREAT IS VERY CONDITIONAL ON STORMS BEING ABLE TO OVERCOME THESE
MITIGATING FACTORS. SPC JUST HAS A GENERAL THUNDER RISK FOR TOMORROW
FOR SOUTHERN AREAS. TOMORROW WILL BE THE WARMEST OF THE NEXT FEW
DAYS WITH HIGHS REACHING THE LOW TO MID 80S FOR MANY VALLEY
AREAS.
KEY MESSAGE 2...THURSDAY NIGHT INTO FRIDAY, THE FRONT FINALLY PUSHES
WELL SOUTH OF OUR REGION, THUS ENDING THE THREAT FOR SEVERE WEATHER
THROUGH THE REMAINDER OF THE FORECAST PERIOD. AN UPPER TROUGH/ULL
OVER THE GOLF OF MAINE COULD LEAD TO A FEW ISOLATED SHOWERS FRIDAY
OR SATURDAY (SLIGHTLY BETTER CHANCE AS A SHORTWAVE ROTATES AROUND
THE ULL), ESPECIALLY FOR WESTERN NEW ENGLAND. AS THE UPPER LOW
DEPARTS TO THE EAST SUNDAY INTO EARLY NEXT WEEK AND UPPER RIDGING
BUILDS BACK OVERHEAD, SFC HIGH PRESSURE BUILDS DOWN FROM THE NORTH.
THIS SHOULD LEAD TO MAINLY DRY AND TRANQUIL WEATHER THROUGH EARLY
NEXT WEEK. TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY BELOW NORMAL
FOR THE WEEKEND AND EARLY NEXT WEEK.
AVIATION /18Z WEDNESDAY THROUGH MONDAY/
AS OF 18 UTC/02, WIDESPREAD MVFR CIGS CONTINUE WITH AN AREA OF
SHOWERS TRACKING FROM WEST TO EAST THROUGH ALB AND POU. THESE
SHOWERS LOOK TO REACH PSF SHORTLY AFTER 18 UTC WITH A FEW BRIEF
SHOWERS NEAR GFL. A THUNDERSTORM IS JUST SOUTH OF POU SO
INCLUDED VCTS FOR THIS SITE ONLY THROUGH 21 UTC. SHOWERS
DIMINISH BY 20 - 21 UTC FROM WEST TO EAST WITH A BRIEF FOR DRY
WEATHER THROUGH EARLY EVENING WITH CIGS AT GFL AND ALB EVEN
TRENDING UPWARDS BACK TO VFR FOR A PERIOD. HOWEVER, GUIDANCE
REMAINS IN GOOD AGREEMENT WITH AN ORGANIZED AREA OF RAIN AND
EMBEDDED THUNDERSTORMS TRACKING FROM WESTERN/CENTRAL NY EASTWARD
REACHING ALB/GFL FIRST FOLLOWED BY PSF/POU NEXT BETWEEN 03 - 06
UTC. WHILE INSTABILITY WILL BE ELEVATED, THERE IS ENOUGH
EVIDENCE THAT RUMBLES OF THUNDER AND PERIODS OF MODERATE TO
HEAVY RAIN CAN OCCUR AT ALL TERMINALS FOR A BRIEF WINDOW SO
INCLUDE A TEMPO GROUP FROM 03 - 08 UTC TONIGHT THAT RESULT IN
IFR CIGS AND VIS. THE HEAVIEST RAIN AND ANY STORMS SHOULD END BY
07-08 UTC WITH LINGERING RAIN SHOWERS ENDING FROM NORTHWEST TO
SOUTHEAST BY 09 - 11 UTC. CIGS AT GFL/PSF LOOK TO DROP IFR
DURING THIS PERIOD WHILE ALB/POU CIGS SHOULD RETURN TO MVFR. IFR
CIGS AT PSF/GFL SHOULD IMPROVE TO MVFR TOWARDS THE END OF THE
TAF PERIOD WITH VFR CONDITIONS LIKELY RETURNING TO ALL TERMINALS
SHORTLY AFTER THE TAF PERIOD ENDS.
SOUTHEASTERLY WINDS 5-12KTS WITH GUSTS UP TO 15-20KTS THROUGH
THIS EVENING SHIFT TO THE WEST - NORTHWEST AS THE AREA OF RAIN
AND EMBEDDED THUNDERSTORMS PUSHES THROUGH THE TERMINALS
OVERNIGHT. WESTERLY WINDS CONTINUE THROUGH THE END OF THE TAF
PERIOD SUSTAINED 5-10KTS WITH GUSTS UP TO 15KTS.
OUTLOOK...
THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: LOW OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
LABOR DAY: NO OPERATIONAL IMPACT. NO SIG WX.
ALY WATCHES/WARNINGS/ADVISORIES
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
DISCUSSION...35
AVIATION...31
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