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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
550 PM EDT SUN MAY 24 2015

.SYNOPSIS...
A WARM FRONT WILL LIFT NORTH ACROSS THE GREAT LAKES 
TONIGHT...BRINGING A FEW HIGH CLOUDS AND A CHANCE OF SHOWERS TO THE 
SAINT LAWRENCE VALLEY. BEHIND THE WARM FRONT...LOOK FOR VERY WARM 
AND GENERALLY DRY CONDITIONS FOR THE MEMORIAL DAY HOLIDAY. WITH HIGH 
PRESSURE REMAINING ANCHORED OFF THE EAST COAST...WARM AND MOIST 
RETURN FLOW WILL KEEP SUMMER-LIKE TEMPERATURES AND A CHANCE OF 
SHOWERS AND THUNDERSTORMS IN THE FORECAST THROUGH MUCH OF THE 
UPCOMING WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
SUNSHINE IS BECOMING MORE FILTERED ACROSS WESTERN AND NORTH-CENTRAL 
NEW YORK THIS AFTERNOON AS HIGH CLOUDS ARE STARTING TO STREAM ACROSS 
THE AREA IN ASSOCIATION WITH WARM ADVECTION ALOFT AHEAD OF AN 
APPROACHING SURFACE WARM FRONT. THE FRONT WILL LIFT NORTH ACROSS THE 
GREAT LAKES TONIGHT...HOWEVER AS THE LOW LEVEL JET AND THUS THE BULK 
OF THE ISENTROPIC UPLIFT WILL BE DISPLACED WELL TO OUR WEST ACROSS 
EASTERN ONTARIO AND THE OTTAWA VALLEY...EXPECT IT TO REMAIN DRY 
ACROSS THE FORECAST AREA TONIGHT WITH ONLY A SLIGHT CHANCE OF 
SHOWERS ACROSS THE SAINT LAWRENCE VALLEY LATE. THE WARM AIR SURGING 
NORTH ACROSS THE REGION WILL RESULT IN A VERY MILD NIGHT WITH LOWS 
IN THE MID TO UPPER 50S. 

MEMORIAL DAY WILL USHER IN A RETURN TO SUMMER AS THE AREA WILL BE 
LOCATED FIRMLY WITHIN THE WARM SECTOR OF A SURFACE/MID-LEVEL LOW 
OVER THE WESTERN GREAT LAKES. WARM AIR ALOFT WILL LARGELY STYMIE ANY 
CONVECTION ACROSS MUCH OF THE FORECAST AREA...THOUGH WITH INCREASING 
DEWPOINTS ON RETURN FLOW...CANNOT RULE OUT A FEW SHOWERS FIRING 
ALONG THE LAKE ERIE LAKE BREEZE IN THE AFTERNOON. THE ONLY OTHER 
AREA WHERE WE MAY SEE A CHANCE OF SHOWERS AND POSSIBLY A 
THUNDERSTORM OR TWO WILL BE ACROSS THE NORTH COUNTRY...CLOSER TO THE 
WARM FRONTAL BOUNDARY. THE AFOREMENTIONED SOUTHERLY RETURN FLOW WILL 
BOOST TEMPERATURES WELL INTO THE 80S...WITH READINGS HITTING THE MID 
TO UPPER 80S ALONG AND NORTH OF THE THRUWAY WHERE SOUTHERLY 
DOWNSLOPING WILL HELP BUMP READINGS UP A COUPLE OF DEGREES. THE ONLY 
AREAS THAT MAY REMAIN IN THE 70S WILL BE IMMEDIATELY ADJACENT TO THE 
COOLER LAKES AND THE NORTH COUNTRY...WHERE A SYNOPTICALLY ENHANCED 
LAKE BREEZE AND CLOUDINESS ASSOCIATED WITH THE WARM FRONT WILL KEEP 
TEMPERATURES DOWN SLIGHTLY.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
MONDAY NIGHT A SURFACE WARM FRONT WILL FINISH ITS NORTHWARD EXIT 
THROUGH THE CWA USHERING IN WARMER...AND MORE HUMID AIR. A FEW 
SHOWERS AND THUNDERSTORMS WILL LIKELY LINGER EAST OF LAKE ONTARIO 
MONDAY EVENING IN THE VICINITY OF THE WARM FRONT. ADDITIONALLY 
SHOWERS AND THUNDERSTORMS OVER THE OHIO VALLEY MONDAY 
AFTERNOON...FORMING TO THE LEE OF A BUILDING UPPER LEVEL RIDGE MAY 
SNEAK INTO WESTERN NEW YORK DURING THE EVENING HOURS. WITH THE LOSS 
OF DAYTIME HEATING AFTERNOON AND EVENING CONVECTION WILL DIMINISH 
THROUGH THE MID AND LATE EVENING HOURS. IT WILL REMAIN WARM 
OVERNIGHT WITH LOWS ONLY IN THE LOW TO MID 60S. 

TUESDAY WILL HAVE A TASTE OF SUMMER TO THE DAY AS A LARGE UPPER 
LEVEL RIDGE OF HIGH PRESSURE BUILDS ALONG THE EASTERN COASTLINE. 
INITIALLY THE LOWER ATMOSPHERE WILL BE CAPPED...WITH SUNSHINE AND 
CLOUDS AROUND. WITH 850 HPA TEMPERATURES AROUND +15C SURFACE HEATING 
THROUGH THE DAY WILL BRING SBCAPES 500 TO 1000 J/KG. THIS 
INSTABILITY...AND THE WEAKENING OF THE CAP SHOULD ALLOW FOR 
AFTERNOON SHOWERS AND THUNDERSTORMS TO BLOSSOM. THERE SHOULD BE 
ENOUGH WIND ALOFT...0-6KM SHEAR OF 30 KNOTS TO ALLOW THESE STORMS TO 
GROW...WITH A FEW POSSIBLE INLAND STRONG STORMS IN THE AFTERNOON.  

A WEAK WAVE ALOFT WILL PASS THROUGH THE CENTRAL GREAT LAKES/LAKE 
ERIE REGION TUESDAY NIGHT AND EARLY WEDNESDAY WHICH WILL MAINTAIN 
CHANCES FOR SHOWERS AND THUNDERSTORMS TUESDAY NIGHT. WITH NO CHANGE 
IN AIRMASS THE AIR TEMPERATURES TUESDAY NIGHT WILL BE SIMILAR TO THE 
PRIOR NIGHT WITH LOWS IN THE LOW TO MID 60S. 

ON WEDNESDAY A WEAK SURFACE FRONT ACCOMPANYING UPPER LEVEL SHORTWAVE 
TROUGH WILL SLIDE ACROSS THE REGION. WILL CONTINUE WITH HIGH CHANCE 
POPS...AND EVEN SOME LIKELY POPS AS MORE FAVORABLE LIFTING WILL BE 
FOUND THIS DAY IN ADDITION TO FAVORABLE INSTABILITY AND MOISTURE. 
ADDITIONAL CLOUD COVER ON WEDNESDAY WILL BRING AFTERNOON 
TEMPERATURES A FEW DEGREES COOLER WITH TEMPERATURES IN THE MID 70S 
TO LOWER 80S.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE STRONG RIDGE OF 
HIGH PRESSURE OVER THE EAST COASTLINE EARLY WEEK...WILL NOW BE OFF 
THE ATLANTIC COASTLINE TO START THIS TIME PERIOD. THIS WILL ALLOW 
SUBTLE SHORTWAVES TO TRACK CLOSER TO THE EASTERN GREAT LAKES REGION 
AND MAINTAIN LOW CHANCES FOR SHOWERS AND THUNDERSTORMS. GREATEST 
CHANCES THURSDAY AND FRIDAY WILL BE INLAND AND ALONG LAKE BREEZES 
WHERE AFTERNOON INSTABILITY AIDED BY LIFT FROM LAKE BREEZE 
CIRCULATION SHOULD TRIGGER A FEW SHOWERS AND THUNDERSTORMS. WITH THE 
UPPER LEVEL RIDGE NOW EASTWARD WE SHOULD NOT BE AS CAPPED AS EARLIER 
IN THE WEEK...ALLOWING MORE FAVORABLE CONDITIONS FOR STORMS TO BREW. 
WILL MAINTAIN LOW CHANCES POPS IN THE GRIDS...THOUGH MUCH OF THE 
TIME SHOULD BE RAIN FREE.  

AS WE HEAD TOWARDS THE WEEKEND 12Z GLOBAL MODELS INDICATE A COLD 
FRONT WITH MORE WIDESPREAD SHOWERS AND THUNDERSTORMS WILL PASS 
THROUGH THE REGION. DIFFERENCES ARE THAT THE GFS IS A BIT 
FASTER...WHILE THE ECMWF WITH SEVERAL CONVECTIVE SURFACE WAVES ON 
THE FRONT IS SLOWER. WILL HAVE HIGH CHANCES POPS FOR BOTH WEEKEND 
DAYS TO ACCOUNT FOR THE UNCERTAINTY...BUT NONE THE LESS THIS FRONT 
REPRESENTS THE GREATEST CHANCES FOR SHOWERS AND THUNDERSTORMS THIS 
TIME PERIOD. 

TEMPERATURES WILL CONTINUE TO AVERAGE ABOVE NORMAL. WARMEST PERIOD 
WILL LIKELY BE FRIDAY/SATURDAY AHEAD OF THE COLD FRONT WHERE UPPER 
70S TO MID 80S WILL BE FOUND ACROSS THE REGION. IT WILL TURN BRIEFLY 
COOLER BEHIND THE FRONT TO CLOSE OUT THE WEEKEND.

&&

.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
HIGH CLOUDS ARE INCREASING IN COVERAGE ACROSS THE FORECAST AREA THIS 
AFTERNOON AS A WARM FRONT APPROACHES THE REGION. CLOUDS WILL THICKEN 
AND LOWER INTO A MID-LEVEL DECK AROUND 10KFT LATER THIS EVENING AS 
THE FRONT LIFTS NORTH ACROSS THE LOWER GREAT LAKES TONIGHT. THE BULK 
OF THE CONVERGENCE AND LIFT ASSOCIATED WITH THE FRONT WILL REMAIN 
FOCUSED WELL TO THE NORTH ACROSS ONTARIO/QUEBEC...SUGGESTING THAT 
THE BULK OF ANY CONVECTION SHOULD OCCUR ACROSS CANADA LATE TONIGHT 
AND INTO MONDAY. THAT SAID THE FRONT WILL BE DRAPED CLOSE ENOUGH TO 
THE AREA TO WARRANT AT LEAST A CHANCE OF SHOWERS/ISOLATED 
THUNDERSTORMS ACROSS THE SAINT LAWRENCE VALLEY ON MONDAY. 

OTHERWISE...THE REST OF THE FORECAST AREA WILL REMAIN DRY THROUGH 
TONIGHT. INCREASING SOUTHERLY RETURN FLOW BEHIND THE FRONT MAY PUMP 
UP SFC DEWPOINTS ENOUGH TO TRIGGER A FEW SHOWERS ALONG LAKE ERIE 
LAKE BREEZE MONDAY AFTERNOON...HOWEVER WARM TEMPERATURES ALOFT IN 
SHOULD LARGELY SUPPRESS CONVECTION ACROSS THE FORECAST AREA WITH VFR 
CONDITIONS PREVAILING THROUGH THE REST OF THE PERIOD.

OUTLOOK... 
MONDAY THROUGH THURSDAY...MAINLY VFR WITH ISOL/SCT -SHRA/TSRA.

&&

.MARINE...
HIGH PRESSURE DOCKED OFF THE MID ATLANTIC COAST WILL EXTEND BACK 
ACROSS THE LOWER GREAT LAKES THROUGH TONIGHT...AND THIS WILL KEEP A 
RELATIVELY WEAK SFC PRESSURE GRADIENT IN PLACE. THE RESULT WILL BE 
GENTLE TO MODERATE WINDS FOR BOTH LAKES ERIE AND ONTARIO WITH WAVES 
AVERAGING 2 FEET OR LESS.

THE HIGH WILL REMAIN IN PLACE OFF THE MID ATLANTIC COAST THROUGH AT 
LEAST MID WEEK...AND THIS WILL KEEP A MODERATE SOUTHWEST FLOW IN 
PLACE ACROSS THE LOWER GREAT LAKES. WHILE GENERALLY SUB SMALL CRAFT 
ADVISORY CONDITIONS ARE EXPECTED... THERE WILL BE THE RISK FOR 
NEARLY DAILY THUNDERSTORM ACTIVITY ALONG WITH A LIGHT 
CHOP...PARTICULARLY ON THE EAST ENDS OF THE LAKES.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...WOOD
NEAR TERM...WOOD
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...WOOD
MARINE...CHURCH/WOOD

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