Scientific Forecaster Discussion

NWS Discussion
			
				
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
341 PM EDT TUE JUN 18 2013

.SYNOPSIS...
A BROAD AREA OF HIGH PRESSURE WILL SETTLE OVER THE GREAT LAKES 
REGION TONIGHT AND REMAIN OVER THE NORTHEAST THROUGH THE END OF THE 
WORK WEEK. THIS AREA OF HIGH PRESSURE WILL PROMOTE FAIR 
WEATHER...COMFORTABLE LEVELS OF HUMIDITY...AND COOL NIGHTS. THE 
WEEKEND WILL BECOME WARMER WITH INCREASING LEVELS OF HUMIDITY.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
EARLY THIS AFTERNOON A BROAD AREA OF HIGH PRESSURE IS FOUND JUST 
NORTH OF THE GREAT LAKES...AND THIS FEATURE WILL CONTINUE TO SLOWLY 
BUILD SOUTHEASTWARD TONIGHT. WE ARE SEEING SOME CLEARING ACROSS THE 
NORTH COUNTRY THIS EARLY AFTERNOON AND AS THE SURFACE HIGH PRESSURE 
CONTINUES TO PUSH SOUTHEASTWARD...COUPLED WITH DEPLETION OF MID 
LEVEL MOISTURE CLOUDS WILL QUICKLY ERODE THROUGH THE LATE AFTERNOON 
AND EVENING FROM NORTH TO SOUTH. 

FOR TONIGHT EXPECT SKIES TO BE MAINLY CLEAR. A FEW PATCHES OF MID 
LEVEL CLOUDS ARE POSSIBLE AS BOTH THE NAM AND GFS BRING AN INCREASE 
OF MOISTURE AROUND 5K FEET FROM JUST NORTH OF LAKE ONTARIO TO ACROSS 
WNY. LIGHT NORTHERLY WINDS WITH THE CENTER OF THE SFC HIGH PRESSURE 
BUILDING TO CENTRAL MICHIGAN. IT WILL BE A COOL NIGHT WITH LOWS 
DROPPING DOWN INTO THE 40S...MID 40S ACROSS THE INTERIOR 
VALLEYS...AND UPPER/AROUND 50 NEAR THE LAKE SHORES. 

FOR TOMORROW HIGH PRESSURE WILL PUSH FROM MICHIGAN TO LAKE ERIE 
THROUGH THE DAY. DAYTIME HEATING WILL BRING FAIR WEATHER CU ACROSS 
THE REGION...MOST PLENTIFUL ACROSS THE HILLS SOUTH OF BUFFALO WHERE 
FOR A TIME SKIES WILL BE PARTY CLOUDY. TEMPERATURES ALOFT AT 850 HPA 
WILL AVERAGE +5 TO +6C WHICH WILL BRING COOL AFTERNOON HIGHS IN THE 
MID TO UPPER 60S.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
LATEST MODELS CONTINUING TO SUPPORT A STRETCH OF FAIR WEATHER FOR 
WESTERN AND CENTRAL NEW YORK AS HIGH PRESSURE REMAINS OVERHEAD. 
TEMPERATURES WILL CONTINUE TO BE COOLER THAN NORMAL THROUGH 
THURSDAY. AS THE HIGH SHIFTS OFF TO THE EAST FRIDAY....WARMTH FROM 
THE OHIO VALLEY WILL BEGIN TO SHIFT OUR WAY WITH A BUILDING UPPER 
RIDGE. THIS WILL TAKE HIGHS FRIDAY TO AROUND 80...JUST IN TIME FOR 
THE SUMMER SOLSTICE.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
THE FOCUS FOR THIS PORTION OF THE FORECAST WILL CENTER ON THE 
EVOLUTION OF THE PACIFIC NORTHWEST UPPER TROUGH AND EXPECTED 
DOWNSTREAM MID/UPPER RIDGE AMPLIFICATION ACROSS EASTERN CONUS 
THROUGH THE WEEKEND AND EARLY NEXT WEEK. STRENGTHENING SOUTHWEST
LOW LEVEL FLOW AND INCREASED LOW LEVEL Theta-e ADVECTION WILL TAKE 
HOLD BY THE WEEKEND. THIS PATTERN SEEMS TO SUPPORT AT LEAST THE 
POSSIBILITY FOR SOME SCATTERED CONVECTION TO DEVELOP AT LEADING EDGE 
OF THIS Theta-e ADVECTION AND JUST AHEAD OF PRONOUNCED EASTWARD 
ADVANCING MID LEVEL THERMAL RIDGE AND SURFACE WARM FRONT SATURDAY. 

LATEST ECMWF APPEARS TO BE SHOWING SOME TREND TO THE PAST SEVERAL 
RUNS OF THE GFS IN ADVERTISING A MORE ROBUST UPPER RIDGE ACROSS THE 
REGION FOR LATER IN THE WEEKEND AND INTO EARLY NEXT WEEK. CONFIDENCE 
IN PRECIPITATION POTENTIAL AT THIS FORECAST DISTANCE IS QUITE LOW 
GIVEN THE POTENTIAL OF RIDGE RIDING SHORT WAVES TO INDUCE CONVECTIVE 
DEVELOPMENT THAT COULD DROP SOUTHEAST ACROSS THE AREA DURING THIS 
PERIOD. STRENGTH OF ANY CAPPING ALSO WILL BE HIGHLY DEPENDENT ON LOW 
LEVEL DEW POINT TRENDS WHICH REMAIN UNCERTAIN. AT THIS POINT...WILL 
MAINTAIN LOW END CHANCE CATEGORY PROBABILITIES ACROSS THE AREA IN 
THE SUNDAY THROUGH TUESDAY TIME FRAME. 

THERE IS MORE CONFIDENCE IN A MUCH WARMER PERIOD WITH MOST OF THE 
MEDIUM RANGE GUIDANCE AND ENSEMBLE SPREAD SUGGESTING HIGHS IN THE 
80S. IF CAP DOES HOLD THROUGH MUCH OF THIS PERIOD...A POSSIBILITY 
DOES EXIST FOR EVEN WARMER CONDITIONS LATE WEEKEND/EARLY NEXT WEEK 
THAN CURRENTLY FORECAST.

&&

.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
AT 18Z A FEW PATCHES OF MVFR CIGS ARE FOUND ACROSS WNY. AS MID LEVEL 
MOISTURE DIMINISHES AND SURFACE HIGH PRESSURE FROM THE NORTHERN 
GREAT LAKES BUILDS SOUTHEASTWARD A FULL RETURN TO VFR IS EXPECTED BY 
EARLY EVENING...WITH VFR FLIGHT CONDITIONS UNDER LIGHT NORTHERLY 
WINDS CONTINUING THROUGH THE REMAINDER OF THE TAF PERIOD. 

OUTLOOK...  
WEDNESDAY THROUGH FRIDAY...VFR.
SATURDAY AND SUNDAY...VFR WITH A CHANCE OF SHOWERS AND 
THUNDERSTORMS.

&&

.MARINE...
HIGH PRESSURE BUILDING SOUTHEAST ACROSS THE LOWER GREAT LAKES WILL 
RESULT IN LIGHT WINDS AND NEGLIGIBLE WAVES INTO WEDNESDAY. FINE 
BOATING CONDITIONS WITH PLENTY OF SUNSHINE IS EXPECTED THROUGH 
FRIDAY.

&&

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

&&

$$

SYNOPSIS...THOMAS
NEAR TERM...THOMAS
SHORT TERM...TMA
LONG TERM...TMA
AVIATION...THOMAS
MARINE...THOMAS