699  
FXUS61 KALY 131927  
AFDALY  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE ALBANY NY  
327 PM EDT MON JUL 13 2020  
   
SYNOPSIS
 
 
A FRONTAL SYSTEM WILL MOVE EAST OF THE AREA THIS EVENING WITH  
SCATTERED SHOWERS AND THUNDERSTORMS ENDING AROUND SUNSET. A  
SLIGHTLY DRYER AIR MASS WILL FOLLOW BEHIND THE FRONT. UPPER  
LEVEL LOW PRESSURE WILL BRING SCATTERED SHOWERS AND  
THUNDERSTORMS TO THE AREAR AGAIN LATE TONIGHT THROUGH TUESDAY,  
THEN HIGH PRESSURE WILL BRING SEASONABLY WARM WEATHER ON  
WEDNESDAY.  
 

 
   
NEAR TERM /UNTIL 6 AM TUESDAY MORNING/
 
 
A COUPLE OF MID- LEVEL SHORT WAVES ARE TRACKING ACROSS THE AREA  
THIS AFTERNOON, WHILE A SURFACE COLD FRONT TRACKS ACROSS AND  
EAST OF THE AREA BY EARLY EVNEING. THESE SYSTEMS WILL TRIGGER  
SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON, DIMINISHING  
BY EVENING. DRYER AIR AT THE SURFACE AND ALOFT IS ALREADY  
FILTERING INTO THE AREA THIS AFTERNOON SUCH THAT IT APPEARS THAT  
THE THREAT FOR ANY HEAVY RAIN TODAY IS DIMINISHING. ANY SHOWERS  
SHOULD BE OVER BY SUNSET.  
 
AFTER A LULL IN THE RAIN CHANCES LATE THIS EVENING, A MID-  
LEVEL LOW PRESSURE AREA WILL TRACK FROM THE EASTERN GREAT LAKES  
ACROSS NORTHERN NEW YORK LATER TONIGHT. THIS SYSTEM WILL  
INCREASE THE CHANCE OF RAIN SHOWERS FOR AWHILE LATE TONIGHT INTO  
TUESDAY MORNING, MAINLY FOR THE NORTHERN HALF OF THE AREA NORTH  
OF THE CAPITAL DISTRICT. THERE MAY BE ENOUGH ELEVATED  
INSTABILITY FOR SOME THUNDER WITH THESE SHOWERS AS THEY MOVE  
ACROSS THE AREA LATE TONIGHT THROUGH EARLY TUESDAY MORNING.  
 

 
   
SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/
 
 
MID-LEVEL LOW PRESSURE WILL CLOSE OFF OVER NORTHEASTERN NY AND  
NORTHERN NEW ENGLAND FOR A TIME ON TUESDAY, BEFORE WEAKENING AND  
LIFTING EAST-NORTHEAST LATER IN THE DAY. THE DAY MAY START WITH  
A FEW SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THE UPPER LOW,  
WITH THE BEST CHANCES NORTH AND EAST OF THE CAPITAL DISTRICT.  
AFTER ANOTHER LULL IN THE RAIN CHANCES LATER TUESDAY MORNING,  
SCATTERED SHOWERS AND THUNDERSTORMS WILL LIKELY DEVELOP TUESDAY  
AFTERNOON WITH THE MAXIMUM OF DIURNAL HEATING. WIND FIELDS AND  
INSTABILITY ON TUESDAY AFTERNOON WILL BE QUITE MODEST AND THE  
RISK FOR ANY SEVERE WEATHER WITH THESE STORMS LOOKS TO BE QUITE  
LOW AT THIS TIME. TEMPERATURES TUESDAY WILL BE A BIT COOLER THAN  
TODAY WITH HIGHS NEAR 80 IN THE VALLEYS AND IN THE 70S OVER  
HIGHER TERRAIN.  
 
A STRONG RIDGE OF THE SOUTH CENTRAL U.S. WILL BEGIN TO BUILD  
NORTHEAST TOWARD OUR AREA LATER TUESDAY AND WEDNESDAY, PUSHING  
THE MID-LEVEL TROUGH OFF TO THE EAST AND SETTING THE STAGE FOR  
ANOTHER ROUND OF WARM AND MOSTLY DRY WEATHER. TEMPERATURES  
WEDNESDAY SHOULD BE ABOUT 5 DEGREES WARMER THAN TUESDAY WITH  
HIGHS MOSTLY IN THE 80S AND LITTLE TO NO CHANCE OF RAIN.  
 

 
   
LONG TERM /THURSDAY THROUGH MONDAY/
 
 
THE LONG TERM WILL BEGIN WITH A PAIR OF UPPER-LEVEL SHORTWAVES  
PASSING ACROSS THE REGION, ONE ON THURSDAY AND ANOTHER ON FRIDAY. AT  
THE SURFACE, AN AREA OF LOW PRESSURE WILL TRACK FROM THE OHIO VALLEY  
THROUGH THE ST. LAWRENCE VALLEY. IT IS UNCERTAIN WHETHER THE COLD  
FRONT WILL PASS THROUGH OR PART OF THE REGION, OR STALL TO OUR NORTH  
AND WEST.  
 
THURSDAY WILL LIKELY BEGIN WITH SOME PARTS OF THE REGION IN A LOW-  
LEVEL STRATUS DECK DUE TO A SOUTHEASTERLY ONSHORE FLOW. PARTIAL  
CLEARING IS ANTICIPATED DURING THE AFTERNOON HOURS. AREAS WELL TO  
THE NORTH AND WEST OF THE CAPITAL DISTRICT WILL HAVE THE HIGHER  
CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS, GIVEN THE  
INSTABILITY AND FORCING IS GREATER ACROSS THAT REGION. FROM THE  
CAPITAL DISTRICT AND POINTS SOUTH AND EAST, LITTLE IF ANY  
INSTABILITY SHOULD LEAD TO NOTHING MORE THAN SOME ISOLATED SHOWERS  
AT BEST. ANY LINGERING SHOWERS WILL PROGRESS EASTWARD ACROSS THE  
ENTIRE REGION OVERNIGHT.  
 
ON FRIDAY, WE STILL LOOK TO BE IN THE WARM SECTOR OF THIS SYSTEM,  
WHERE GREATER INSTABILITY SHOULD LEAD TO MORE SCATTERED COVERAGE OF  
SHOWERS AND THUNDERSTORMS, PENDING ON HOW LONG IT TAKES ANY  
LINGERING CLOUDS AND SHOWERS FROM THE MORNING TO DISSIPATE. THIS  
SYSTEM DEPARTS THE REGION FRIDAY NIGHT.  
 
FROM SATURDAY THROUGH MONDAY, UPPER-LEVEL RIDGING REBUILDS; HOWEVER,  
THERE ARE MODEL DIFFERENCES REGARDING THE STRENGTH OF THE RIDGE AND  
WHETHER ANY UPPER-LEVEL FEATURES PUSH ACROSS THE REGION. FOR NOW,  
WILL MAINTAIN SLIGHT CHANCE POPS FOR AFTERNOON/EVENING SHOWERS AND  
THUNDERSTORMS SATURDAY AND SUNDAY DUE TO THE HOT AND HUMID  
CONDITIONS. ON MONDAY, A COLD FRONT MAY APPROACH FROM THE NORTH AND  
WEST AND LEAD TO AT LEAST SCATTERED SHOWER/T-STORM COVERAGE.  
 
TEMPERATURES TO BEGIN THE PERIOD WILL RANGE FROM THE MID- TO UPPER  
70S IN THE HIGHER TERRAIN TO THE LOW TO MID-80S IN THE VALLEYS, THEN  
TREND UPWARDS TO THE 80S IN THE HIGHER TERRAIN AND LOW TO MID-90S IN  
THE VALLEYS.  
 

 
   
AVIATION /20Z MONDAY THROUGH SATURDAY/
 
 
THE MAIN FORECAST CONCERN FOR THE TERMINALS THROUGH THE TAF PERIOD  
WILL FOCUS ON THE COVERAGE, TIMING, AND PROBABILITY OF SHOWERS AND  
THUNDERSTORMS. OUTSIDE OF ANY RAIN SHOWERS OR THUNDERSTORMS THAT  
COULD BRING CIGS/VSBYS TO MVFR LEVELS, VFR CONDITIONS WILL PERSIST  
THROUGH THE TAF PERIOD.  
 
THE FA AREA THROUGH THE TAF PERIOD WILL HEAVILY BE UNDER THE  
INFLUENCE OF MEAN UPPER LEVEL TROUGHING OVERHEAD AND MULTIPLE MID-  
UPPER LEVEL IMPULSES ASSOCIATED WITH IT. AIDED BY AFTERNOON HEATING,  
SHOWERS AND THUNDERSTORMS IS EXPECTED TO INCREASE IN COVERAGE OVER  
THE FA THIS AFTERNOON/EVENING. THIS IS EVIDENT VIA THE HI-RES  
MODELS. SHOWER AND THUNDERSTORM ACTIVITY DEPICTED FROM THE MODELS  
ARE ISOLATED TO WIDELY SCATTERED. GIVEN THE NATURE OF THIS, HAVE  
INCLUDED VCSH AND VCTS FOR THE TAF SITES TO START THE PERIOD. KGFL  
IS THE SITE THAT HAS THE BEST CHANCE AND COVERAGE FOR SHOWERS AND  
THUNDERSTORMS THROUGH THE TAF PERIOD AS IT'S IN BETTER  
POSITION/PROXIMITY TO THE AFOREMENTIONED UPPER TROUGH AND ASSOCIATED  
SMALL MID-UPPER LEVEL IMPULSES. FOR KGFL, THUNDER ACTIVITY SHOULD BE  
REDUCED TO MAINLY SHOWERY (NON-CONVECTIVE) ACTIVITY AFTER 00Z. FOR  
KALB AND KPSF, VCSH SHOULD DIE DOWN AT OR AROUND 21Z AND POSSIBLY  
PICK UP AGAIN DURING THE OVERNIGHT HOURS. FOR KPOU, VCTS SHOULD COME  
TO AN END AROUND 20Z. BEING FURTHEST TO THE SOUTH, KPOU HAS THE BEST  
CHANCE COMPARED TO THE OTHER SITES TO REMAIN DRY THEREAFTER.  
 
ISOLATED TO SCATTERED SHOWERS AND STORMS ARE POSSIBLE TOMORROW  
MORNING/AFTERNOON PRIMARILY FOR AREAS ALONG AND NORTH OF I-90.  
 
WINDS GENERALLY WILL BE OUT OF THE WEST-NORTHWEST 5-10 KTS DURING  
THE DAY TAPERING DOWN TO LESS THAN 5 KTS AT NIGHT.  
 
OUTLOOK...  
 
TUESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.  
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.  
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.  
THURSDAY: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHRA.  
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SHRA.  
FRIDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.  
FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.  
SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.  
 

 
   
FIRE WEATHER
 
 
A FRONTAL SYSTEM AND UPPER LEVEL DISTURBANCE WILL BRING  
SCATTERED SHOWERS TO THE AREA LATE THIS AFTERNOON THROUGH  
TUESDAY. HUMIDITY LEVELS WILL DROP JUST A BIT LATE THIS  
AFTERNOON, BEFORE RISING BACK TO 90 TO 100 PERCENT LATE TONIGHT.  
FAIR CONDITIONS RETURN FOR WEDNESDAY, BEFORE HUMIDITY LEVELS AND  
CHANCES FOR SHOWERS AND THUNDERSTORMS INCREASE BY LATE NEXT  
WEEK. TEMPERATURES WILL ALSO TREND BACK TOWARDS THE 90S BY NEXT  
WEEKEND.  
 
RH VALUES WILL INCREASE TO 90 TO 100 PERCENT LATE TONIGHT,  
BEFORE FALLING TO 50 TO 60 PERCENT ON TUESDAY AFTERNOON.  
SOUTHWEST TO NORTHWEST WINDS WILL AVEERAGE 5 TO 10 KTS TONIGHT,  
BECOMING LIGHT NORTHWESTERLY ON TUESDAY.  
 

 
   
HYDROLOGY
 
 
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED  
INTO TUESDAY. LOCALIZED RAINFALL AMOUNTS OF UP TO AROUND HALF AN  
INCH WILL CAUSE PONDING IN POOR DRAINAGE AREA, BUT SIGNIFICANT  
FLOODING IS NOT EXPECTED. WATER LEVELS ON THE MAIN RIVERS WILL  
REMAIN STEADY THROUGH THIS WEEK.  
 
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...MSE  
NEAR TERM...MSE/NAS  
SHORT TERM...MSE  
LONG TERM...RATHBUN  
AVIATION...EVBUOMA  
FIRE WEATHER...MSE/NAS  
HYDROLOGY...NAS/MSE  
 
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