643  
FXUS61 KALY 261955  
AFDALY  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE ALBANY NY  
355 PM EDT FRI MAY 26 2017  
   
SYNOPSIS
 
 
RAIN SHOWERS NORTH AND EAST OF THE CAPITAL DISTRICT WILL SLOWLY  
DIMINISH INTO THIS EVENING AS LOW PRESSURE DEPARTS, SETTING UP A  
MILDER AND MAINLY DRY SATURDAY. IT WILL BE SLIGHTLY WARMER STILL  
ON SUNDAY WITH A MIXTURE OF SUN AND CLOUDS. SHOWERS AND POSSIBLY  
A FEW THUNDERSTORMS ARE LIKELY SUNDAY NIGHT INTO MEMORIAL DAY.  
 

 
   
NEAR TERM /UNTIL 6 AM SATURDAY MORNING/
 
 
STACKED UPPER LOW STILL CHURNING OVER THE GULF OF MAINE. NARROW  
DEFORMATION ZONE WITHIN ENHANCED MIDLEVEL THETA-E CORRIDOR  
WRAPPING BACK INTO THE SYSTEM FROM THE NORTH AND WEST IS LEADING  
TO THE CONTINUATION OF SHOWERS MAINLY FROM THE WESTERN  
ADIRONDACKS TO THE CAPITAL DISTRICT TO THE BERKSHIRES AND POINTS  
NORTH AND EAST. JUST A FEW SHOWERS TO THE SOUTH AND WEST WHERE  
SHALLOW CONVECTION AND ALSO A FEW CLOUD BREAKS ARE OCCURRING.  
HI-RES MODELS INDICATE THE STEADIER ACTIVITY BREAKING UP AFTER  
22Z OR SO, SO HAVE TAPERED POPS BACK TO CHANCE AFTERWARD. A GOOD  
DEAL OF CLOUD COVER SHOULD CONTINUE OVERNIGHT FOR MUCH OF THE  
AREA AS THERE IS PLENTIFUL CLOUD COVER UPSTREAM AND NOT A REAL  
GOOD DRYING SIGNAL, THOUGH HAVE WORKED IN A VERY GRADUAL PARTIAL  
CLEARING TREND FROM SOUTHWEST TO NORTHEAST. WITH THE CLOUD  
COVER, LOWS TONIGHT IN THE MID-40S TO LOW 50S WILL BE SLIGHTLY  
ABOVE SEASONAL NORMALS.  
 

 
   
SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/
 
 
MEAN UPPER RIDGING BUILDS IN SATURDAY INTO SUNDAY, WHICH SHOULD  
RESULT IN MAINLY QUIET WEATHER FOR THE FIRST PART OF THE HOLIDAY  
WEEKEND. ONLY FLY IN THE OINTMENT APPEARS TO BE TIED TO THE MCV  
NOW TRACKING ACROSS ILLINOIS. MODEL CONSENSUS IS FOR THE MCV TO  
DAMPEN OUT AS IT TRACKS INTO THE MEAN RIDGING. GFS, WHICH HAD  
BEEN THE MOST AMPLIFIED WITH THE MCV, HAS NOW TRENDED LESS-  
AMPLIFIED. THE UPSHOT IS THAT MOST AREAS WILL REMAIN DRY ON  
SATURDAY; HOWEVER, HAVE CONTINUED SLIGHT CHANCE POPS OVER OUR  
SOUTHERN TIER OF COUNTIES SATURDAY AFTERNOON/EVENING AS THE  
NORTHERN FRINGE OF THE PRECIP ASSOCIATED WITH THE MCV MAY JUST  
BRUSH THE REGION. OTHERWISE, AT LEAST PARTIAL SUNSHINE IS  
EXPECTED, THOUGH UPSTREAM CLOUD COVER AND ONLY WEAK HIGH  
PRESSURE/SUBSIDENCE SUGGESTS A HEALTHY CLOUD FRACTION WILL  
REMAIN. HIGH TEMPS WILL BE SEVERAL DEGREES WARMER THAN RECENT  
DAYS, THOUGH LIKELY STILL COMING UP A BIT SHORT OF NORMAL. QUIET  
ONCE AGAIN SATURDAY NIGHT UNDER SUBSIDENT NORTHWESTERLY FLOW.  
SOME FOG IS NOT OUT OF THE QUESTION DEPENDING ON THE DEGREE OF  
CLEARING AS THE BOUNDARY LAYER WILL REMAIN SOMEWHAT MOIST.  
 
UPPER RIDGING WILL CREST OVER THE REGION SUNDAY, GIVING WAY TO  
WEAK HEIGHT FALLS SUNDAY NIGHT AS THE FIRST IN A SERIES OF  
IMPULSES EMANATING FROM A DEEP AND EXPANSIVE UPPER LOW NEAR LAKE  
SUPERIOR APPROACHES. SUNDAY IS EXPECTED TO BE A TAD WARMER THAN  
SATURDAY AS 925 MB TEMPS WARM BY AROUND 4C UNDER PARTIAL CLOUD  
COVER. HOWEVER, CLOUDS WILL BE INCREASING LATE IN THE DAY AHEAD  
OF THE IMPULSE. INCREASING LOW-LEVEL JET/MOISTURE TRANSPORT  
AHEAD OF THE IMPULSE WILL BRING A CHANCE OF SHOWERS TO THE  
FORECAST AREA SUNDAY NIGHT, WITH LIKELY POPS AFTER 06Z WEST OF  
THE HUDSON VALLEY. HOWEVER, MODELS HAVE TRENDED SLOWER WITH THIS  
SYSTEM AS OF LATE, SO LATEST FORECAST SLOWS DOWN THE ARRIVAL OF  
POPS. SOME ELEVATED INSTABILITY WORKS INTO AREAS WEST OF THE  
HUDSON VALLEY, SO HAVE KEPT SLIGHT CHANCE THUNDER IN THE  
FORECAST SUNDAY NIGHT.  
 

 
   
LONG TERM /MONDAY THROUGH THURSDAY/
 
 
THE EXTENDED PORTION OF THE FORECAST CONTINUES TO LOOK UNSETTLED FOR  
MUCH OF NEXT WEEK WITH A MEAN LONGWAVE TROUGH OVER SOUTH/SOUTHEAST  
CANADA, THE UPPER MIDWEST, GREAT LAKES REGION INTO THE NORTHEAST.  
SEVERAL DISTURBANCES WILL IMPACT THE FORECAST AREA UNTIL LATE IN THE  
WORK WEEK.  
 
MEMORIAL DAY... A SHORT-WAVE IN THE SOUTHWESTERLY FLOW ALOFT QUICKLY  
APPROACHES THE REGION MONDAY MORNING. AFTER A WARM FRONTAL PASSAGE,  
A WEAK COLD/OCCLUDED FRONT WILL FOCUS SHOWERS AND A SLIGHT CHC OF  
THUNDERSTORMS DURING THE LATE MORNING INTO THE AFTERNOON BASED ON  
THE LATEST GEFS/GFS/ECMWF/CAN GGEM. THE SHOWALTER STABILITY INDICES  
BRIEFLY BECOME NEGATIVE WITH SOME ELEVATED INSTABILITY COUPLED WITH  
MUCAPE VALUES GENERALLY 500 J/KG OR LESS ESPECIALLY WEST OF THE  
HUDSON RIVER VALLEY. POPS WERE RAISED TO LIKELY VALUES FROM WEST TO  
EAST ACROSS THE ENTIRE FORECAST AREA, AS WELL AS AN AREA OF  
CATEGORICAL VALUES WAS USED NORTH AND EAST OF THE CAPITAL REGION  
DURING THE DAY. H850 TEMPS ARE IN THE +8C TO +10C RANGE, BUT LOTS OF  
CLOUDS AND THE RAIN COOLED AIR SHOULD KEEP MAX TEMPS COOLER THAN  
NORMAL WITH HIGHS GENERALLY IN THE UPPER 60S TO AROUND 70F IN THE  
VALLEYS, AND UPPER 50S TO MID 60S OVER THE HILLS AND MOUNTAINS.  
 
MONDAY NIGHT INTO TUESDAY...A SURFACE LOW MAY FORM ALONG THE FRONT  
AND PASS SOUTH OF NEW ENGLAND MONDAY NIGHT FOR SOME SCATTERED  
SHOWERS TO LINGER ESPECIALLY SOUTH AND EAST OF THE CAPITAL REGION.  
THE UPPER LEVEL TROUGH AMPLIFIES AND THE GEFS HAS H500 HEIGHT OVER  
THE UPPER MIDWEST/GREAT LAKES REGION 1 TO 2 STANDARD DEVIATIONS  
BELOW NORMAL. ANOTHER SHORT-WAVE ROUNDS THE BASE OF THE TROUGH FROM  
THE OH VALLEY AND EASTERN GREAT LAKES REGION WITH ANOTHER ROUND OF  
SHOWERS AND SLIGHT CHANCE OF THUNDERSTORMS AHEAD OF A COLD FRONT.  
THE 12Z GFS HAS A BIT MORE INSTABILITY /MUCAPES IN THE 500-1000+  
J/KG RANGE/AND 0-6 KM BULK SHEAR VALUES OF 50 KTS, SO SOME OF THE  
THUNDERSTORMS COULD BE ON THE STRONG SIDE IF ENOUGH HEATING OCCURS.  
THERE ARE SOME SIGNALS OF STEEPENING MID LEVEL LAPSE RATES TO 6.5-  
7C/KM. WE KEPT THE THUNDERSTORM THREAT AT A SLIGHT CHANCE FOR NOW,  
BUT THIS MAY HAVE TO BE RAISED LATER IF THE THUNDERSTORM THREAT  
BECOMES CLEARER. AFTER LOWS IN THE UPPER 40S TO MID 50S, MAX TEMPS  
WILL BE SEASONABLE IN THE MID 60S TO MID 70S ACROSS THE FORECAST  
AREA.  
 
TUESDAY NIGHT INTO THURSDAY...THE BROAD UPPER LEVEL TROUGH DRIFTS  
OVER SOUTHEAST CANADA, THE GREAT LAKES REGION AND NORTHEAST. A  
SERIES OF SFC TROUGHS AND MID LEVEL SHORT-WAVES MOVE ACROSS THE  
REGION IN THE CYCLONIC FLOW. SCATTERED SHOWERS TIED TO THE DIURNAL  
HEATING WILL BE POSSIBLE WED AND THU AFTERNOONS. THERE COULD BE  
SOME SMALL HAIL, AS THE COLD POOL MOVES NEAR THE REGION. THE SHOWERS  
COVERAGE SHOULD DISSIPATE EACH EVENING, ALTHOUGH THE BETTER CYCLONIC  
VORTICITY ADVECTION INITIALLY WILL SET-UP NORTH AND WEST OF THE  
CAPITAL REGION ON WED. LOWS WILL RANGE FROM THE MID/UPPER 40S OVER  
THE MTNS TO LOWER TO MID 50S IN THE VALLEYS EACH NIGHT WITH UPPER  
60S TO MID 70S FOR HIGHS IN THE LOWER ELEVATIONS, AND UPPER 50S TO  
MID 60S OVER THE HILLS AND MOUNTAINS, AS THESE TEMPS ARE A SHADE  
BELOW NORMAL FOR LATE MAY INTO EARLY JUNE.  
 
THU NIGHT INTO FRIDAY, THERE ARE SOME SIGNALS IN THE MEDIUM RANGE  
GUIDANCE THAT THE LONGWAVE TROUGH AXIS MOVES DOWNSTREAM AS WELL AS  
THE CORE OF THE COLDEST AIR ALOFT WITH SOME RIDGING BUILDING  
EASTWARD FROM THE GREAT LAKES REGION. A SLIGHT CHC OF SHOWERS WAS  
KEPT IN THE GRIDS, BUT THIS LOOKS LIKE THE BEST CHANCE OF A DRY DAY  
BASED ON THE LATEST EC/GFS. TEMPS STILL LOOK SLIGHTLY BELOW NORMAL  
FOR EARLY JUNE.  
 

 
   
AVIATION /19Z FRIDAY THROUGH WEDNESDAY/
 
 
LOW PRESSURE CONTINUES MOVE NORTHEAST TOWARDS NOVA SCOTIA THIS  
AFTERNOON. THE UPPER LEVEL TROUGH TO THE SYSTEM AND MOIST  
CYCLONIC FLOW WILL CONTINUE TO IMPACT THE TAF SITES WITH  
SCATTERED SHOWERS ESPECIALLY FROM KALB-KSPF NORTH AND EAST INTO  
THIS EVENING. LOW-LEVEL MOISTURE WILL LINGER MOST OF THE  
OVERNIGHT PERIOD INTO TOMORROW MORNING, AS SOME WEAK RIDGING  
BEGINS TO BUILD IN ACROSS THE REGION FOR SATURDAY.  
 
MVFR CONDITIONS PREVAIL AT THE TAF SITES THIS AFTERNOON WITH  
SOME CIGS LOWERING TO IFR LEVELS AT KGFL/KPSF IN THE LIGHT  
RAIN/SHOWERS. IFR CONDITIONS WILL BE POSSIBLE AT KGFL AND KPSF  
UNTIL 21Z-00Z. THE CIGS CONTINUE TO INCREASE TO HIGH MVFR  
LEVELS AT KPOU WITH SOME LIGHT RAIN/DRIZZLE AT KALB WITH MVFR  
CIGS. THE TRENDS WILL BE FOR THE SHOWERS TO DECREASE THIS  
EVENING, BUT THE MODEL SOUNDINGS CONTINUE TO SHOW LOW-LEVEL  
MOISTURE TRAPPED BENEATH AN INVERSION MOST OF THE NIGHT TIME  
PERIOD. CIGS IN THE 1.5-3.0 KFT AGL RANGE WILL BE COMMON AT  
KGFL/KALB/KPSF. THERE IS THE POSSIBILITY OF LIFR/IFR CIGS AT  
KPSF IF A LITTLE CLEARING OCCURS AFTER 06Z, BUT WE DID NOT  
INCLUDE IT AT THIS TIME DUE TO LOW CONFIDENCE. KPOU MAY BRIEFLY  
RISE TO LOW VFR LEVELS LATE THIS AFTERNOON INTO THE EARLY  
EVENING, BUT HIGH MVFR CIGS AT 3 KFT AGL ARE POSSIBLE ONCE AGAIN  
AFTER 04Z/SAT THERE.  
 
THE CIGS WILL SLOWLY INCREASE FROM MVFR LEVELS TO VFR BETWEEN  
12Z-16Z/SAT AS SOME SUBSIDENCE INCREASES IN THE WAKE OF THE  
DEPARTING CYCLONE AND SOME WEAK RIDGING BUILDS IN. KPSF WILL  
LINGER THE LONGEST WITH HIGH MVFR CIGS UNTIL THE LATE  
MORNING/EARLY AFTERNOON.  
 
THE WINDS WILL BE FROM THE N TO NW AT 5-10 KTS LATE THIS  
AFTERNOON, AND WILL GENERALLY BE LIGHT FROM THE NORTHWEST AT 5  
KTS OR LESS TONIGHT. LIGHT AND VARIABLE DIRECTION WINDS OF 5  
KTS OR LESS ARE LIKELY LATE TOMORROW MORNING INTO THE EARLY  
AFTERNOON.  
 
OUTLOOK...  
 
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.  
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.  
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.  
MEMORIAL DAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA.  
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.  
TUESDAY: HIGH OPERATIONAL IMPACT. LIKELY SHRA...TSRA.  
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.  
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.  
 

 
   
FIRE WEATHER
 
 
SLIGHTLY WARMER AND DRIER SATURDAY WITH LIGHT NORTHWESTERLY  
WINDS. A BIT WARMER STILL ON SUNDAY WITH LIGHT SOUTHERLY WINDS.  
RH VALUES WILL BOTTOM OUT IN THE 50S BOTH DAYS. SHOWERS AND A  
FEW THUNDERSTORMS BECOME LIKELY SUNDAY NIGHT INTO MEMORIAL DAY.  
 

 
   
HYDROLOGY
 
 
MAINLY DRY WEATHER IS EXPECTED SATURDAY AND SUNDAY. AN  
APPROACHING SYSTEM WILL BRING THE LIKELIHOOD OF SHOWERS AND A  
FEW THUNDERSTORMS SUNDAY NIGHT INTO MEMORIAL DAY, WITH TOTAL QPF  
RANGING FROM 0.25-0.75" EXPECTED. ADDITIONAL PERIODS OF SHOWERS  
AND THUNDERSTORMS ARE LIKELY TUESDAY AND WEDNESDAY.  
 
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.  
 

 
   
EQUIPMENT
 
 
THE ASOS IN GLENS FALLS AT THE FLOYD BENNETT MEMORIAL AIRPORT  
CONTINUES TO EXPERIENCE OUTAGES WITH HOURLY METARS OCCASIONALLY  
MISSING. THIS WILL CONTINUE UNTIL COMMUNICATIONS ARE FULLY  
RESTORED.  
 

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

 
 

 
SYNOPSIS...THOMPSON  
NEAR TERM...THOMPSON  
SHORT TERM...THOMPSON  
LONG TERM...WASULA  
AVIATION...WASULA  
FIRE WEATHER...THOMPSON  
HYDROLOGY...THOMPSON  
EQUIPMENT...WFO ALY  
 
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