Flash Flooding and Lightning Strike in New York, August 5, 2003

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE ALBANY NY
1148 AM EDT TUE AUG 5 2003

.DISC...WILL UPDATE ZONES TO REFLECT CURRENT THINKING OF ISSUING A
FLASH FLOOD WATCH FOR PORTIONS OF  THE CWA THAT HAVE RECD SEVERAL
INCHES OF RAIN THIS PAST WEEK. WL UPDATE ZNS TO ACCOUNT FOR THIS
WATCH WHICH WILL RUN THROUGH 1130 PM. SAME AIRMASS OVER THE CWA SO
EXPECT SAME WX FOR TODAY AS THE PAST FEW DAYS WITH SHWRS/TSTMS LKLY
ACRS THE CWA WITH TORRENTIAL DOWNPOURS POSSIBLE. CANNOT RULE OUT
SOME PLACES RECEIVING 2 TO 4 INCHES OF RAIN OR MORE IF CELLS DEVLOP
AND TRAIN OVER A PARTICULAR AREA SO WITH THAT IN MIND HAVE OPTED FOR
THE FFA FOR THESE COUNTIES.

NO OTHER CHNAGE PLANNED ATTM FOR THE REMAINDER OF THE PDS.

.....................................................................

...FROM PREVIOUS

.DISCUSSION...
THE LARGE UPPER-LEVEL GYRE TO OUR WEST HAS PROGRESSED SLOWLY TO THE
EAST SINCE FORMING OVER THE NORTHEASTERN PLAINS OF THE UNITED STATES
ON JULY 30.  MONDAY EVENING IT WAS NEARLY VERTICAL THROUGH A DEEP
LAYER OF THE ATMOSPHERE.  THE WATER VAPOR IMAGERY SUGGESTED A SPLIT
IN VORTICITY MAXIMUMS.  ONE WAS NEAR JAMES BAY, ANOTHER WAS NEAR THE
THE SOUTH SHORE OF LAKE HURON.  THE HIGH-LEVEL TROUGH HAS BEEN
SHARPENING, AND THAT IS FORECAST TO CONTINUE TODAY AS THE TROUGH
TRENDS TOWARD A SLIGHT NEGATIVE TILT.  THE TOTAL PRECIPITABLE WATER
IS NOT FORECAST TO BE QUITE AS HIGH FOR TODAY AS IT WAS YESTERDAY
WHEN VALUES IN EXCESS OF 2 INCHES WERE FORECAST IN THE EASTERN
ZONES.  TODAY, THE TOTAL PRECIPITABLE WATER ACROSS THE REGION
AVERAGES JUST SHY OF AN INCH AND THREE QUARTERS.  PERHAPS THIS IS THE
RESULT OF A LITTLE DRIER AIR HAVING COME IN AT THE HIGH ALTITUDES.
THERES BEEN NO APPARENT CHANGES IN THE LOW LAYERS OF THE ATMOSPHERE.

A STRONG LOW-LEVEL JET IS FORECAST OFF THE ATLANTIC COAST TODAY,
WITH WINDS IN EXCESS OF 50 KNOTS IN THE CORE OF THIS FEATURE.  THE
STRONGEST LOW-LEVEL SHEAR IS OFF THE ATLANTIC COAST AS WELL.  MUCH
LIGHTER LOW-LEVEL WIND IS FORECAST ACROSS EASTERN NEW YORK AND
WESTERN NEW ENGLAND.  A HIGH-LEVEL WIND MAXIMUM, APPROACHING 90
KNOTS, IS FORECAST TO DRIFT EASTWARD AND BE OVER THE WESTERN ZONES
THIS EVENING.  SOME DYNAMICS ARE SUGGESTED LATE TODAY IN THE
VICINITY OF THE WESTERN ZONES IN ASSOCIATION WITH THIS FEATURE.  THE
LOW-LEVEL WIND MAXIMUM OFF THE ATLANTIC COAST FAVORS THE BEST
LOW-LEVEL CONVERGENCE ALONG, OR OFF THE ATLANTIC COAST.  THESE
SIGNATURES SEEM TO FAVOR THE LOWEST PROBABILITY OF PRECIPITATION IN
THE EASTERN OR CENTRAL PORTION OF THE COUNTY WARNING AREA TODAY.
HOWEVER, THERE ARE DIFFERENCES IN MODEL FORECASTS OF MEASURABLE
PRECIPITATION, AND THESE ARE REFLECTED IN DIFFERENCES IN THE MODEL
PROBABILITIES TOO.  THE AVIATION HAS THE LOWEST PROBABILITIES IN THE
WEST.  BUT ALL THE MODELS SHOW AT LEAST LIKELY VALUES TODAY, AND ALL
ARE FORECASTING AT LEAST LIGHT MEASURABLE PRECIPITATION.  THE
CANADIAN REGIONAL MODEL HAS THE LEAST WET SOLUTION FOR TODAY. THE
ZONE FORECAST THAT WILL BE RELEASED LATER THIS MORNING WILL BE GOING
WITH LIKELY PROBABILITIES THROUGHOUT THE COUNTY WARNING AREA (60 OR
70 PERCENT).  LITTLE CHANGE IN MAXIMUM TEMPERATURE FROM THAT NOTED
OVER THE PAST SEVERAL DAYS HAS BEEN FORECAST BY THE NEW GUIDANCE.

THE MODELS SUGGEST THAT A SHORT WAVE WILL EVOLVE OUT OF THE SHARP
UPPER-LEVEL TROUGH TO THE WEST OF THE COUNTY WARNING AREA LATER
TODAY.  THIS IS FORECAST TO MOVE EAST AND SHOULD BEGIN TO ENHANCE
THE PRECIPITATION LATE TONIGHT OR EARLY WEDNESDAY IN EASTERN NEW
YORK AND WESTERN NEW ENGLAND.  THERE ARE DIFFERENCES IN TIMING THIS
FEATURE.  THE CANADIAN REGIONAL MODEL IS SLIGHTLY SLOWER THAN THE
ETA MODEL.  THE AVIATION AND ETA INDICATED THAT THE HIGH-LEVEL WIND
MAXIMUM WOULD ALIGN FAVORABLY FOR SIGNIFICANT UPPER LEVEL DIVERGENCE
AS THE TROUGH MOVED TOWARD THE COUNTY WARNING AREA.  THE NESTED
GRID MODEL WAS NOT AS FAVORABLE AS IT FORECAST A WEAKER WIND MAXIMUM
FURTHER EAST THAN THE ETA OR AVIATION.  MODEL CONSENSUS ON THE IDEA
THAT SOME SORT OF WAVE WOULD ENHANCE PRECIPITATION, SUGGESTS THAT IT
WOULD BE PRUDENT TO KEEP THE PROBABILITY OF PRECIPITATION AT LEAST
AT THE LIKELY LEVEL IN MUCH, IF NOT ALL OF THE COUNTY WARNING AREA
FOR TONIGHT AND WEDNESDAY.  LITTLE CHANGE IN MINIMUM OR MAXIMUM
TEMPERATURES ARE INDICATED BY THE LATEST GUIDANCE, AND THIS IS
REASONABLE AS THE SAME AIR MASS WILL CONTINUE TO COVER THE REGION.

THE SHORT-WAVE SHOULD BE EAST OF THE AREA WEDNESDAY NIGHT, AND THE
UPPER-LEVEL WIND MAXIMUM WILL BE FAR ENOUGH EAST, SO THAT SOME
SINKING CAN OCCUR OVER THE COUNTY WARNING AREA.  THEREFORE IT IS
BELIEVED THAT THERE MAY BE A BREAK IN THE PRECIPITATION WEDNESDAY
NIGHT.  NEVERTHELESS, THE MAIN UPPER-LEVEL TROUGH AXIS WILL CONTINUE
TO LIE TO THE WEST OF THE EASTERN NEW YORK, WHICH MAKES IT LESS
CERTAIN THAT IT WILL BE ENTIRELY DRY WEDNESDAY NIGHT.  THE MODEL
GUIDANCE PROBABILITIES ALL SUGGEST A CHANCE OF RAIN FOR WEDNESDAY
NIGHT.  THE LOWER AVIATION VALUES ARE PREFERRED.

FOR SEVERAL RUNS, THE AVIATION AND CANADIAN GLOBAL MODELS HAVE BEEN
LATCHING ONTO A WEAK WAVE IN THE SOUTHEASTERN UNITED STATES AND
MOVING IT NORTHEAST THROUGH THE ATLANTIC COASTAL REGION.  THIS COULD
HAVE AN IMPACT ON THE COUNTY WARNING AREA, ESPECIALLY THE EASTERN
PORTION.  THE IDEA OF THE WAVE CONTINUES ON THE LATEST RUN OF THE
AVIATION AND CANADIAN GLOBAL MODELS, HOWEVER, THE CANADIAN GLOBAL
PLACES LESS EMPHASIS ON IT THAN SOME OF THE PREVIOUS MODEL RUNS.
THE ETA FAVORS AN EVEN DRIER SOLUTION FOR THURSDAY.

MONDAYS ZONE FORECAST FOR THURSDAY HAD ONLY A SLIGHT CHANCE OF
PRECIPITATION.  HOWEVER, IN VIEW OF THE HISTORY OF THE MODEL RUNS,
AND THE LOCATION OF THE UPPER-LEVEL TROUGH TO THE WEST, A 30 OR 40
PERCENT CHANCE OF RAIN AS IS FORECAST BY THE LATEST AVIATION
GUIDANCE DOES NOT SEEM UNREASONABLE.  THE SLIGHT CHANCE
PROBABILITIES FOR THURSDAY WILL BE BUMPED UP SLIGHTLY ON THE NEXT
FORECAST.

THE AVIATION AND CANADIAN GLOBAL MODELS CONTINUE TO FORECAST
MEASURABLE PRECIPITATION LATE IN THE WEEK.  MONDAYS ZONE FORECAST
HAD A CHANCE OF PRECIPITATION.  NO CHANGES WILL BE MADE TO THE
EXTENDED PART OF THE FORECAST.

.HYDROLOGICAL DISCUSSION...
WITH THE TROPICAL AIR MASS REMAINING OVER THE REGION FOR SEVERAL
MORE DAYS, THERES THE THREAT OF GULLY-WASHERS, ESPECIALLY DURING
THE AFTERNOON AND EARLY EVENING HOURS.  HOWEVER, IT IS ALL BUT
IMPOSSIBLE TO PINPOINT THE LOCATION OF THESE, AND THE CHANCE OF
FLOODING AT ANY PARTICULAR LOCATION IS BELOW 30 PERCENT, SO NO FLOOD
WATCHES WILL BE ISSUED.

.ALY...NONE.

CTZ001-013-MAZ001-025-NYZ032-033-038>043-047>054-058>061-063>066-
082>084-VTZ013>015-060330-

HAZARDOUS WEATHER OUTLOOK...CORRECTION
NATIONAL WEATHER SERVICE ALBANY NY
1142 AM EDT TUE AUG 5 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN NEW YORK AND ADJACENT
WESTERN NEW ENGLAND.

.DAY ONE...TODAY AND THIS EVENING...A FLASH FLOOD WATCH HAS BEEN
ISSUED FOR THE FOLLOWING COUNTIES...SCHOHARIE...MONTGOMERY...
GREENE...ULSTER...SCHENECTADY...SOUTHERN HERKIMER...SARATOGA...
SOUTHEAST WARREN...WASHINGTON...FULTON...BENNINGTON AND WINDHAM.

TORRENTIAL DOWNPOURS MAY BE POSSIBLE IN THESE AREAS THAT HAVE
ALREADY RECEIVED SEVERAL INCHES OF RAIN THE PAST FEW DAYS.

.DAYS TWO THOUGH SEVEN...
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED.

CORRECTED FOR EXPIRATION TIME