486  
FXUS61 KALY 171846  
AFDALY  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE ALBANY NY  
246 PM EDT MON AUG 17 2026  
   
WHAT HAS CHANGED
 
 
PATCHY FOG WAS EXPANDED FURTHER ACROSS EASTERN NY AND WESTERN NEW  
ENGLAND TONIGHT IN THE MOIST AIR MASS BEFORE THE COLD ADVECTION  
INCREASES IN THE WAKE OF THE OCCLUDED FRONT LATE TONIGHT.  
 
PATCHY RADIATIONAL MIST/FOG WAS INCLUDED ACROSS THE SHELTERED  
VALLEYS TUE NIGHT/WED MORNING.  
 
FRIDAY INTO THE WEEKEND LOOKS POTENTIALLY UNSETTLED WITH A WAVE  
MOVING ALONG THE BOUNDARY STALLED SOUTH OF THE REGION  
INITIALLY, AS WELL AS A DEEPENING MID AND UPPER LEVEL TROUGH  
OVER THE GREAT LAKES REGION INTO THE NORTHEAST WITH A CLOSED LOW  
THAT MAY BRING PERIODS OF RAIN ESPECIALLY LATE IN THE WEEKEND.  
 

 
   
KEY MESSAGES
 
 
1)SCATTERED SHOWERS AND ISOLATED TO SCATTERED NON-SEVERE  
THUNDERSTORMS WILL MOVE ACROSS THE REGION THIS AFTERNOON THROUGH  
TONIGHT AHEAD OF THE OCCLUDED FRONT.  
 
2) ANOTHER ROUND OF ISOLATED TO SCATTERED SHOWERS, WITH ISOLATED  
THUNDERSTORMS, IS EXPECTED WED PM INTO THU, AS A COLD FRONT  
SLOWLY MOVES ACROSS THE REGION.  
 
3) POTENTIALLY, UNSETTLED WEATHER RETURNS FRI INTO THE WEEKEND  
AS A BROAD MID AND UPPER LEVEL TROUGH SETTLES IN, ALTHOUGH THERE  
IS LOW CONFIDENCE IN THE TIMING, RAINFALL AMOUNTS AND DETAILS  
WITH THIS SYSTEM.  
 

 
   
DISCUSSION
 
 
KEY MESSAGE 1...  
A COLD FRONT ASSOCIATED WITH LOW PRESSURE OVER SOUTHEAST QUEBEC  
IS CATCHING UP TO A WARM FRONT OVER CENTRAL NY AND PA EARLY  
THIS AFTERNOON, AS A SECONDARY LOW MOVES ACROSS SOUTHEAST NEW  
ENGLAND. A MOIST AND HUMID AIR MASS WILL BRIEFLY IMPACT THE  
REGION WITH DEWPOINTS IN THE 60S TO LOWER 70S THIS AFTERNOON.  
AN OCCLUDED FRONT WILL BRING SOME SCATTERED SHOWERS AND ISOLATED  
TO SCATTERED THUNDERSTORMS. PWATS HAVE RISEN INTO THE 1.5-2.0"  
RANGE ACROSS THE FORECAST AREA BASED ON THE SPC RAP  
MESOANALYSIS, AS THE 12Z KALY SOUNDING WAS 1.94". LOW-LEVEL  
STRATUS IS SLOWLY ERODING TO PARTLY TO MOSTLY CLOUDY CONDITIONS  
THIS AFTERNOON. SBCAPE HAS HAD TROUBLE DEVELOPING FROM THE  
HUDSON RIVER VALLEY/I-87 EASTWARD SO FAR. SBCAPES 500-1000 J/KG  
HAVE BEEN MATERIALIZING NORTH AND WEST OVER THE SOUTHWEST  
ADIRONDACKS. THE LATEST HREFS HAS MEAN SBCAPES OF 750-1250 J/KG  
LATE THIS AFTERNOON INTO THIS EVENING FROM SOUTHERN VT, THE  
CAPITAL REGION, AND THE EASTERN CATSKILLS SOUTH AND EAST WITH  
WEAK DEEP SHEAR 15-25 KT. THE BEST 0-6 KM BULK SHEAR 25-35 KT IS  
OVER THE FAR NORTHWEST ZONES, WHERE SOME SHOWERS AND ISOLATED  
THUNDERSTORMS ARE DEVELOPING OVER THE WESTERN ADIRONDACKS. THE  
LACK OF ROBUST INSTABILITY, DEEP SHEAR OVER THE MAJORITY THE  
FORECAST AREA, AND WEAK LAPSE RATES ALOFT SHOULD KEEP THE  
THUNDERSTORMS THAT FORM NON-SEVERE. SOME GUSTY WINDS AND BRIEF  
LOCALIZED DOWNPOURS COULD PRODUCE PONDING OF WATER WITH A FEW  
STORMS.  
 
THE FRONT WILL MOVE ACROSS THE REGION SLOWLY TONIGHT WITH THE  
ABUNDANT LOW-LEVEL MOISTURE REMAINING IN PLACE, AS WIDESPREAD  
PATCHY FOG TO LOCALIZED AREAS OF DENSE FOG WILL LIKELY FORM,  
ESPECIALLY WHERE RAIN OCCURS. LOWS FALL BACK INTO THE MID 50S TO  
MID 60S WITH THE COOLEST READINGS WEST OF THE HUDSON RIVER  
VALLEY OVER THE HIGHER TERRAIN. SOME MODEST COLD ADVECTION WILL  
OCCUR OVER THE NORTHWEST ZONES LATE.  
 
KEY MESSAGE 2...  
 
A FEW LINGERING SHOWERS PERSIST OVER SOUTHERN VT IN THE  
MORNING, AS HIGH PRESSURE BUILDS IN ACROSS THE REGION WITH  
PARTLY TO MOSTLY SUNNY CONDITIONS AND SEASONABLE TEMPS. HIGH  
WILL BE SEASONABLE IN THE THE 80-85F RANGE IN THE VALLEYS AND  
MAINLY 70S OVER THE HILLS AND MTNS. A WINDOW OF MOSTLY CLEAR  
SKIES AND LIGHT TO CALM WINDS WILL ALLOW FOR SOME PATCHY  
RADIATIONAL VALLEY MIST/FOG IN THE SHELTERED VALLEYS, AS LOWS  
WILL BE IN THE 50S AROUND 60F. THE FRONTAL BOUNDARY APPROACHES  
FOR WED WITH A SLIGHT TO LOW CHANCE OF SHOWERS AND THUNDERSTORMS  
ESPECIALLY NORTH AND WEST OF THE CAPITAL REGION OVER THE  
WESTERN DACKS AND WEST-CENTRAL MOHAWK VALLEY. INSTABILITY LOOKS  
WEAK OR LIMITED WITH WEST-SOUTHWEST LOW TO MID-LEVEL FLOW. THE  
FRONT LOOKS TO WEAKEN AT NIGHT WITH THE SHOWERS/THUNDERSTORMS  
DIMINISHING. TEMPS WILL RUN NEAR OR SLIGHTLY ABOVE SEASONAL  
NORMALS WITH 70S TO LOWER/MID 80S. THE FRONTAL BOUNDARY MAKES  
SLOW PROGRESS ACROSS THE REGION BY THU MORNING. THE BEST CHANCE  
FOR ISOLATED TO SCATTERED THUNDERSTORMS WILL BE ALONG AND  
SOUTHEAST OF SOUTHERN VT, THE GREATER CAPITAL REGION, AND THE  
EASTERN CATSKILLS IN THE AFTERNOON. A FEW THUNDERSTORMS COULD  
BECOME STRONG, IF MODERATE INSTABILITY INCREASES, BUT THAT IS  
UNCLEAR AT THIS THIS TIME WITH THE MEDIUM RANGE GUIDANCE/ENSEMBLES.  
 
KEY MESSAGE 3...  
 
SOME UNCERTAINTY CONTINUES FRI INTO THE WEEKEND. SOME OF THE  
MEDIUM RANGE GUIDANCE HAS A WAVE DEVELOPING ALONG THE STALLED  
FRONT TO THE SOUTH OF THE REGION OVER PA AND NJ FOR SOME RAIN TO  
IMPACT LOCATIONS FROM THE CAPITAL REGION SOUTH AND EAST, WHILE  
THE ECMWF AND SOME ENSEMBLES KEEP IT DRY WITH HIGH PRESSURE  
BUILDING IN. OUR LATEST FORECAST FROM WPC FOR DAYS 4-7 KEEPS IT  
DRY OUTSIDE A SLIGHT CHANCE OF SHOWERS CLOSER TO I-84 ON FRI.  
THE DETERMINISTIC, AI AND ENSEMBLE GUIDANCE CONTINUES TO FORECAST  
A BROAD, DEEPENING MID AND UPPER LEVEL TROUGH OVER SOUTHEAST  
CANADA, THE GREAT LAKES REGION AND THE NORTHEAST FOR THE  
UPCOMING WEEKEND INTO EARLY NEXT WEEK. THE CHANCES OF SHOWERS  
AND FEW THUNDERSTORMS CONTINUE LATE SAT INTO SUN FOR THE TROUGH  
AND A POTENTIAL CLOSED LOW. SOME LOCALLY HEAVY RAIN COULD OCCUR  
DEPENDING WHERE THE MID AND UPPER LEVEL LOW TRACK AND ANY  
SURFACE CYCLONES, BUT TIMING, EVOLUTION DETAILS AND THE AMOUNT  
OF RAINFALL STILL LOOK VERY UNCERTAIN AT THIS TIME. WE WILL  
CONTINUE TO CLOSELY MONITOR TRENDS THROUGH THE WEEK, AS THIS  
STORM SYSTEM IS STILL SEVERAL DAYS AWAY. TEMPS TREND SLIGHTLY  
COOLER THAN NORMAL.  
 

 
   
AVIATION /18Z MONDAY THROUGH SATURDAY/
 
 
WE START THE TAF PERIOD WITH EITHER LOW VFR OR MVFR CONDITIONS  
AT ALL TAF SITES. THROUGH 18/00Z, MVFR AND LOW VFR CEILINGS  
CONTINUE TO FLUCTUATE DUE TO PASSING RAIN SHOWERS AND LOW  
STRATUS CLOUDS. BETWEEN 17/20Z AND 18/00Z, ALL TAF SITES COULD  
SEE A PASSING RAIN SHOWER. FORECAST CONFIDENCE IS LOW FOR A  
THUNDERSTORM THIS AFTERNOON, WITH A VICINITY THUNDERSTORM THE  
MOST LIKELY SCENARIO FOR THIS TIMEFRAME. SO WITH HIGHER  
CONFIDENCE FOR RAIN SHOWER ACTIVITY, CONTINUED MENTIONED RAIN  
SHOWERS IN PROB30 GROUPS THROUGH 18/00Z. THEN, LOW STRATUS AND  
PATCHY FOG DEVELOP FOR THE OVERNIGHT HOURS AS WINDS BECOME CALM  
AND CONDITIONS ARE FAVORABLE, ESPECIALLY ANY TAF SITE THAT SEES  
A RAIN SHOWER TODAY. CONFIDENCE IS HIGHEST FOR KPSF TO DEVELOP  
FOG WHICH HAS BEEN INTRODUCED FOR 18/06Z THROUGH 18/13Z WITH  
LIFR/IFR CONDITIONS. KGFL COULD SEE SOME PATCHY FOG FOR MVFR  
CONDITIONS BETWEEN 3Z AND 6Z, BUT LOW CEILINGS DUE TO LOW  
STRATUS WILL LIKELY PERSIST AFTER 6Z THROUGH 12Z. FOR KALB AND  
KPOU, IFR CEILINGS ARE LIKELY IN STORE AFTER 6Z THROUGH 10-12Z  
DUE TO LOW CEILINGS.  
 
OUTLOOK...  
 
TUESDAY NIGHT: NO OPERATIONAL IMPACT. PATCHY FG.  
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.  
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.  
THURSDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.  
THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.  
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.  
FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.  
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.  
 

 
   
ALY WATCHES/WARNINGS/ADVISORIES
 
 
CT...NONE.  
NY...NONE.  
MA...NONE.  
VT...NONE.  
 

 
 

 
 
DISCUSSION...15  
AVIATION...05  
 
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