323
FXUS61 KALY 211853
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
253 PM EDT TUE JUL 21 2026
WHAT HAS CHANGED
TORNADO WATCH #507 ISSUED FOR WESTERN ADIRONDACKS, MID-HUDSON
VALLEY, NORTHERN/EASTERN CATSKILLS, MOHAWK VALLEY AND NW CT
THROUGH 9PM TONIGHT.
KEY MESSAGES
1) WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED LATE THIS
AFTERNOON INTO THE EVENING, WITH SOME SCATTERED SHOWERS AND
STORMS RETURNING TOMORROW, ESPECIALLY WEST OF THE HUDSON RIVER.
STORMS WILL BE CAPABLE OF PRODUCING HEAVY DOWNPOURS RESULTING
IN LOCALIZED FLOODING AS WELL AS BRIEF GUSTY WINDS, ESPECIALLY
SOUTH AND WEST OF THE CAPITAL DISTRICT.
2) TRANQUIL WEATHER WITH TEMPERATURES TRENDING SLIGHTLY ABOVE NORMAL
THURSDAY INTO THIS WEEKEND.
DISCUSSION
KEY MESSAGE 1...WIDESPREAD CLOUD COVERAGE OVER EASTERN NY AND
WESTERN NEW ENGLAND CONTINUES INTO THIS AFTERNOON AS WE REMAIN
NORTH OF A SFC WARM FRONT POSITIONED IN FAR SOUTHEASTERN
NY/NORTHERN NJ. HOWEVER, THE MID-LEVEL WARM FRONT HAS STARTED TO
ADVANCE NORTHEASTWARD AND DEW POINTS ARE CREEPING FURTHER INTO
THE UPPER 60S TO LOW 70S. WITH THE LATEST VISIBLE SATELLITE
SHOWING SOME THINNING TO THE CLOUD COVERAGE, THE INCREASED
INSOLATION COMBINED WITH AN INCREASINGLY MOIST ENVIRONMENT IS
CONTRIBUTING TO INCREASED INSTABILITY. THE LATEST SPC MESOSCALE
ANALYSIS SHOWS MEAGER ML CAPE VALUES AROUND 500 - 1000 J/KG
MAINLY SOUTH AND WEST OF THE HUDSON RIVER WITH INSTABILITY
QUICKLY TRENDING DOWNWARDS INTO THE CAPITAL DISTRICT AND NORTH
AND EAST. PWATS ARE QUITE HIGH TODAY WELL OVER 1.5" AS THE
LATEST ALPW SATELLITE CHANNELS SHOW A MOISTURE PLUME FROM THE
SOUTHEAST U.S AND WESTERN ATLANTIC NOSING NORTHWARD. FORECAST
SOUNDINGS ALSO SHOW THAT THIS HIGHLY MOIST ENVIRONMENT WILL ALSO
FEATURE HIGH FREEZING LEVEL HEIGHTS 12-13 KFT AND HIGH EL
HEIGHTS SUPPORTING A TALL- SKINNY CAPE SOUNDING. WITH EFFECTIVE
SHEAR ALSO DECENT AT 25 - 35KTS, TODAY IS A CLASSIC ENVIRONMENT
THAT FAVORS HEAVY DOWNPOURS AND THIS CONTINUES TO BE THE PRIMARY
HAZARD FOR TODAY. WE CONSIDERED A FLOOD WATCH FOR THE MID-
HUDSON VALLEY WHERE WPC MAINTAINS ITS SLIGHT RISK IN THE DAY 1
EXCESSIVE RAINFALL OUTLOOK; HOWEVER, DECIDED TO HOLD OFF GIVEN
THIS AREA MISSED OUT ON THE HEAVY RAIN THIS MORNING AND IT
REMAINED MAINLY TO THE SOUTH. WHILE THE LATEST 3-HRLY
PRECIPITATION PMM FROM THE HREF STILL SHOWS A 10 TO LOCALIZED
30% CHANCE FOR 3" OF RAIN IN THREE HOURS IN THE MID-HUDSON
VALLEY AND EASTERN CATSKILLS LATE THIS AFTERNOON INTO THIS
EVENING, THE LATEST 3-HR FFG REMAIN QUITE HIGH AT 2.5 - 3.5".
THUS, EVEN IF THESE RAINFALL RATES ARE REALIZED, RAINFALL
AMOUNTS MAY JUST REACH FFG. IF HEAVY RAIN REPEATEDLY IMPACTS A
GIVEN AREA, IT WILL LIKELY BECOME VULNERABLE TO LOCALIZED
FLOODING INCLUDING EVEN ISOLATED TO SCATTERED FLASH FLOODING BUT
CONFIDENCE IS TOO LOW TO WARRANT A FLOOD WATCH.
BESIDES HEAVY RAIN RESULTING IN LOCALIZED FLOODING, SEVERE
THUNDERSTORMS RESULTING IN DAMAGING WINDS IS A SECONDARY HAZARD
FOR TODAY. AS WAS MENTIONED, FORECAST SOUNDING OVERALL MEAGER
INSTABILITY WITH THE HIGHEST VALUES SOUTH/EAST OF THE CAPITAL
DISTRICT. HOWEVER, FAVORABLE EFFECTIVE SHEAR 30 - 40KTS COMBINED
WITH SUFFICIENT INSTABILITY CAN SUPPORT BOWING SEGMENTS AND
QLCS TYPE STRUCTURES AS THE WARM FRONT LIFTS NORTHWARD.
DAMAGING WINDS ARE THE PRIMARY HAZARD FROM ANY SEVERE STORMS
BUT SOUTHEAST WINDS IN THE LOW-LEVELS QUICKLY VEERING TO THE
WEST-SOUTHWEST ALOFT HAVE LED TO CURVED HODOGRAPHS AND ENHANCED
EFFECTIVE HELICITY VALUES ALONG THE WARM FRONT TO 100-200M2/S2.
THIS MEANS ISOLATED TORNADOES ARE NOT RULED OUT, ESPECIALLY
GIVEN LOW LCLS VALUES. THUS, WE HAVE COLLABORATED WITH SPC AND
NEIGHBORING WFOS TO ISSUE A TORNADO WATCH THROUGH 9PM THIS
EVENING FOR THE MOHAWK VALLEY, WESTERN ADIRONDACKS, NORTHERN AND
EASTERN CATSKILLS, MID-HUDSON VALLEY AND NW CT. VERY HIGH EL
HEIGHTS ALSO MAKES THIS A FAVORABLE ENVIRONMENT FOR FREQUENT
LIGHTNING. LATEST CAMS HAVE STRUGGLED CAPTURING LATEST RADAR
TRENDS BUT AS CONVECTION FROM THE SOUTHERN TIER AND SOUTHEAST NY
TRACKS NORTH AND EAST LATER THIS AFTERNOON, IT WILL RUN INTO A
LESS FAVORABLE ENVIRONMENT AND WEAKEN. THUS, THE LATEST TORNADO
WATCH DOES NOT EXTEND INTO THE CAPITAL DISTRICT OR AREAS NORTH
AND EAST. ANY INITIAL STRONG TO SEVERE STORMS SHOULD WEAKEN
LATE THIS AFTERNOON AS THE ENVIRONMENTS GETS WORKED OVER AND
TRANSITION TO MORE OF A HYDRO CONCERN. SOME SHOWERS WILL STILL
BE AROUND TONIGHT AS THE WARM FRONT FINALLY PUSHES NORTH AND
EAST BUT WILL DIMINISH IN COVERAGE. OTHERWISE, IT WILL REMAIN
VERY MUGGY.
THE WARM SECTOR SHIFTS EASTWARD TOMORROW AS THE MAIN COLD FRONT
AND TROUGH AXIS SWINGS INTO THE NORTHEAST. GIVEN THE EARLY
ARRIVAL OF THE COLD FRONT PUSHING INTO THE EASTERN NY BY 15 - 18
UTC, THE HIGHEST CHANCE FOR THE WARM SECTOR TO HAVE ENOUGH TIME
TO DESTABILIZE BEFORE THE STRONGEST FORCING ARRIVES LOOK TO BE
IN AREAS MAINLY EAST OF THE HUDSON RIVER, ESPECIALLY IN WESTERN
NEW ENGLAND. THE LATEST DAY 2 SPC OUTLOOK CONTINUES TO PLACE A
MARGINAL (LEVEL 1 OF 5) RISK FOR SEVERE WEATHER IN SOUTHERN
BERKSHIRE AND LITCHFIELD COUNTIES WHERE THERE IS A FAVORABLE
OVERLAP OF 500-1000J/KG OF SB CAPE AND 40-45KTS OF DEEP LAYER
SHEAR. LATEST CAMS SHOWS AN INITIAL LINE OF SHOWERS DEVELOPING
ALONG THE INCOMING COLD FRONT LATE MORNING THAT GROWS UPSCALE
INTO LINE SEGMENTS AND STORM CLUSTERS AS IT ENTERS WESTERN NEW
ENGLAND AND THE MORE UNSTABLE ENVIRONMENT MAINLY AFTER 17-18
UTC. DAMAGING WINDS WILL ALSO AGAIN BE THE MAIN HAZARD THROUGH
LATE AFTERNOON BEFORE THE FRONT FINALLY PUSHES EASTWARD INTO
NEW ENGLAND. OTHERWISE, HUMIDITY WILL TREND DOWNWARDS BEHIND
THE COLD FRONT FROM WEST TO EAST THROUGH THE DAY WITH CLEARING
SKIES.
KEY MESSAGE 2...WE WILL ENJOY A STRETCH OF PLEASANT AND DRY WEATHER
THURSDAY THROUGH THIS WEEKEND AS HIGH PRESSURE BUILDS OVERHEAD.
TEMPERATURES TREND UPWARDS FRIDAY INTO THE WEEKEND AS HIGH
PRESSURE BUILDS OFF SHORE PROMOTING SOUTHWESTERLY RETURN FLOW
BUT WE DO NOT EXPECT OPPRESSIVE HEAT. ANOTHER SHORTWAVE
APPROACHES LATE THIS WEEKEND INTO EARLY NEXT WEEK BUT THERE IS
STILL UNCERTAINTY ON TIMING AND PLACEMENT OF ANY SHOWERS OR
CONVECTION.
AVIATION /18Z TUESDAY THROUGH SUNDAY/
THROUGH 18Z WEDNESDAY... MVFR CONDITIONS PREVAIL ACROSS ALL TERMINALS THROUGHOUT THIS AFTERNOON AND EVENING,
DRIVEN BY LOWER CIGS FROM RAIN SHOWERS. MODERATE WINDS OUT OF THE SOUTH TO SOUTHWEST WITH GUSTS UP TO 20-25
KTS WILL ALSO PREVAIL ACROSS ALL TERMINALS THROUGH THE FIRST SEVERAL HOURS OF THIS TAF PERIOD. THERE IS A CHANCE
OF THUNDERSTORMS THIS EVENING AT ALL TERMINALS, WHICH COULD BRING PERIODS OF IFR VIS, LOWER CIGS, AND STRONGER
WINDS/GUSTS. AS RAIN AND STORMS BEGIN TO TAPER OUT IN THE OVERNIGHT HOURS, LOW-LEVEL MOISTURE IS EXPECTED TO STICK
AROUND, LEADING TO WIDESPREAD/MARGINAL IFR CIGS AT ALL TERMINALS, ALTHOUGH VIS WILL BEGIN TO IMPROVE THROUGHOUT THIS
PERIOD. WINDS WILL ALSO SLIGHTLY WEAKEN OVERNIGHT AND WILL START TO VEER TO OUT OF THE SOUTHWEST.
CONDITIONS ARE EXPECTED TO GRADUALLY IMPROVE AFTER SUNRISE ON WEDNESDAY, WITH CIGS RISING BACK UP TO MVFR AND VFR AT
ALL TERMINALS BY THE EARLY AFTERNOON HOURS. WINDS ARE EXPECTED TO STRENGTHEN AGAIN ON WEDNESDAY MORNING AND EARLY AFTERNOON,
WITH THE RETURN OF GUSTS UP TO 15-25 KTS, WHILE SHIFTING TO
PREVAIL OUT OF THE WEST.
OUTLOOK...
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
ALY WATCHES/WARNINGS/ADVISORIES
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
DISCUSSION...31
AVIATION...23
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