Special Weather Statement, NWS Buffalo, NY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
201 PM EDT FRI JUL 5 2013

.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL MAINTAIN A
SOUTHERLY FLOW OF WARM AND VERY HUMID AIR OVER OUR REGION THROUGH
THE WEEKEND. THUNDERSTORMS THAT DEVELOP WITHIN THIS HUMID AIRMASS
WILL BE CAPABLE OF PRODUCING VERY HEAVY RAIN AND GUSTY WINDS...BUT
THERE WILL BE FREQUENT RAINFREE PERIODS AS WELL.

&&

.NEAR TERM /THROUGH SATURDAY/...
NUMEROUS SHOWERS ARE DEVELOPING IN THE UNSTABLE AIRMASS WITH ABOUT
40 KTS OF SHEAR OVER MUCH OF WESTERN AND CENTRAL NY...ENOUGH FOR
SOME WEAK SUPERCELL DEVELOPMENT AT TIMES. EXPECT STORMS TO
CONTINUE TO DEVELOP AS A 60 KT 500MB JET PASSES OVERHEAD PER LATEST
AMDAR DATA AND RAP ANALYSIS...WITH STRONGEST STORMS MOVING OFF TO
THE NORTHEAST EARLY THIS AFTERNOON.  THERE IS LESS SHEAR AND
STABILITY FURTHER UPSTREAM OVER CENTRAL LAKE ERIE/NW PA...SO EXPECT
A LOWER THREAT FOR ANY SEVERE WEATHER DEVELOPMENT LATE TODAY.  AN
ISOLATED THREAT CONTINUES FOR FLOODING...ALTHOUGH THIS THREAT
APPEARS TO BE DIMINISHING WITH TIME.  HOWEVER...WITH PLENTY OF
DAYTIME HEATING LEFT...WILL HAVE TO WATCH FOR THE POSSIBILITY OF
TRAINING CELLS.

LATER THIS EVENING...EXPECT A DIMINISHING TREND TO CONVECTION AS
SHORTWAVE TROUGH MOVES OFF TO THE NORTHEAST AND DAYTIME HEATING
WANES.  WILL FORECAST A LULL IN RAIN POTENTIAL LATER TONIGHT INTO
SATURDAY MORNING.

ON SATURDAY...WILL AGAIN HAVE TO CONTEND WITH ABUNDANT MOISTURE AS
THE BLOCKED UPPER LEVEL PATTERN CONTINUES TO FORCE A PLUME OF
MOISTURE NORTHWARD FROM THE GULF ACROSS THE EASTERN GREAT LAKES
REGION.  WITH THE UPPER LEVEL FLOW A BIT MORE OUT OF THE WEST
INSTEAD OF SW...EXPECT STORM DEVELOPMENT TO BE SUPPRESSED A BIT TO
THE SOUTH/SOUTHEAST COMPARED TO TODAY/FRIDAY...WITH RENEWED
DEVELOPMENT ALONG THE LAKE ERIE BREEZE BOUNDARY AND INTO THE INLAND
SOUTHERN TIER AND PORTIONS OF THE GENESEE VALLEY.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
THE UNSETTLED PATTERN WILL CONTINUE THROUGH THE SHORT TERM AS A MID
LEVEL CUTOFF LOW DRIFTS SLOWLY FROM THE MID MISSISSIPPI VALLEY TO
THE OHIO VALLEY THROUGH THE PERIOD. A STRONG BERMUDA HIGH WILL ALSO
REMAIN IN PLACE...WITH DEEP SOUTHERLY FLOW BETWEEN THESE TWO
FEATURES KEEPING A FEED OF DEEP TROPICAL MOISTURE FROM THE GULF OF
MEXICO FLOWING NORTHWARD INTO THE REGION. NUMEROUS LOW AMPLITUDE AND
DIFFICULT TO TIME SHORTWAVES WILL PROPAGATE AROUND THE WESTERN
PERIPHERY OF THE BERMUDA HIGH THROUGH THE PERIOD AND SUPPORT
ENHANCED COVERAGE OF SHOWERS AND A FEW THUNDERSTORMS AT TIMES. THIS
WILL BE SUPERIMPOSED ON THE DIURNAL CYCLE...WHICH IN GENERAL WILL
SUPPORT BEST COVERAGE OF SHOWERS DURING THE AFTERNOON AND EARLY
EVENING WITH LESSER COVERAGE DURING THE LATE NIGHT AND EARLY MORNING
HOURS.

SATURDAY EVENING MOST OF THIS ACTIVITY WILL SLOWLY DISSIPATE WITH
THE LOSS OF DAYTIME HEATING. LATE SATURDAY NIGHT ONE OR TWO WEAK
SHORTWAVES WILL AGAIN CROSS THE LOWER LAKES REGION ALONG WITH AN
INCREASE IN DEEP LAYER MOISTURE. THIS MAY PRODUCE A FEW WIDELY
SCATTERED SHOWERS LATE.

BY SUNDAY THE MID LEVEL CUTOFF LOW OVER THE MIDWEST WILL BEGIN TO
OPEN UP AND RE-ENGAGE WITH THE WESTERLIES. THIS WILL SPREAD HEIGHT
FALLS AND DPVA INTO THE LOWER LAKES REGION WHICH WILL SUPPORT AN
INCREASE IN LARGE SCALE ASCENT. THIS WILL AGAIN PRODUCE AT LEAST
SCATTERED SHOWERS AND A FEW THUNDERSTORMS...WITH THE GREATEST
COVERAGE EXPECTED FROM THE SOUTHERN TIER INTO THE FINGER LAKES AND
CENTRAL NY WITH SOME HELP FROM THE DIURNAL CYCLE AND ASSOCIATED
DIFFERENTIAL HEATING BOUNDARIES. SUNDAY NIGHT THE MID LEVEL CUTOFF
WILL CONTINUE TO MAKE HEADWAY EAST AND APPROACH THE REGION. THE
INCREASE IN LARGE SCALE ASCENT MAY KEEP A FEW SHOWERS GOING INTO THE
NIGHT DESPITE THE LOSS OF DAYTIME HEATING.

PWAT THROUGH THE PERIOD WILL RUN CLOSE TO 2 INCHES AT TIMES. THIS
WILL CONTINUE TO SUPPORT A RISK FOR TORRENTIAL DOWNPOURS AND
ASSOCIATED ISOLATED FLOOD RISK FROM ANY THUNDERSTORM WHICH
DEVELOPS...ESPECIALLY IF TRAINING OCCURS ALONG ANY OF THE LOW LEVEL
BOUNDARIES.

IT WILL REMAIN MUGGY THROUGH THE PERIOD WITH WARM OVERNIGHT LOWS AND
HIGHS JUST SLIGHTLY ABOVE AVERAGE.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
A SLOW IMPROVING TREND IN SENSIBLE WEATHER WILL TAKE PLACE DURING
THE LONG TERM AS THE PATTERN ACROSS NORTH AMERICA EVOLVES. A ZONAL
PATTERN WILL TAKE HOLD ALONG THE US/CANADIAN BORDER WHICH IN TIME
WILL FORCE DEEPER TROPICAL MOISTURE BACK SOUTH AND AWAY FROM THE
REGION. THE BERMUDA HIGH WILL ALSO WEAKEN A LITTLE AND MOVE FARTHER
OFFSHORE...ENDING THE SOUTHERLY PUMP OF DEEP MOISTURE INTO THE
NORTHEAST STATES.

AT THE START OF THE PERIOD MONDAY AND MONDAY NIGHT THE OLD
MIDWEST CUTOFF LOW WILL PASS BY JUST TO THE SOUTH OF THE AREA. THIS
WILL CONTINUE TO SUPPORT A FEW SCATTERED SHOWERS AND THUNDERSTORMS.
BY TUESDAY A WEAK BUBBLE OF HIGH PRESSURE WILL BUILD INTO THE GREAT
LAKES AND PROVIDE A MUCH NEEDED MAINLY DRY DAY.

BY WEDNESDAY BOTH THE GFS AND ECMWF REMAIN CONSISTENT IN BRINGING A
STRONGER NORTHERN STREAM SHORTWAVE AND ASSOCIATED SURFACE LOW INTO
THE GREAT LAKES REGION. THIS WILL BRING BACK THE CHANCE OF SHOWERS
AND THUNDERSTORMS. THIS SYSTEM WILL PUSH EAST OF THE AREA BY
THURSDAY WITH A RETURN TO MAINLY DRY WEATHER.

TEMPERATURES WILL CONTINUE TO RUN A LITTLE ABOVE AVERAGE THROUGH
MOST OF THE PERIOD WITH VERY MUGGY CONDITIONS. THIS WILL IMPROVE BY
THURSDAY WITH A DRIER AND LESS HUMID AIRMASS BUILDING INTO THE
REGION BEHIND A STRONGER COLD FRONT.

LOOKING A LITTLE FARTHER AHEAD...SOME PROMISE IS SEEN FOR A MORE
EXTENDED PERIOD OF DRYING LATER NEXT WEEK THROUGH NEXT WEEKEND AS A
BAROCLINIC ZONE GETS FORCED MAINLY SOUTH OF THE AREA AS A TROUGH
DIGS INTO EASTERN CANADA. THIS WOULD PUT OUR REGION ON THE DRIER AND
LESS HUMID SIDE OF THE BOUNDARY...WITH LOWER RH DAYS GIVING SOILS A
CHANCE TO DRY OUT.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
A MOISTURE LADEN AIRMASS WILL REMAIN IN PLACE ACROSS THE REGION
THROUGH THE TAF PERIOD. A SHORT WAVE TROUGH WILL PUSH EAST ACROSS
CENTRAL NEW YORK DURING THIS AFTERNOON AND INTERACT WITH VERY MOIST
AIR WITH THUNDERSTORMS ONCE AGAIN DEVELOPING IN THE INCREASINGLY
UNSTABLE AIRMASS.  THESE STORMS WILL SLOWLY HEAD NE DURING THE
REMAINDER OF THE AFTERNOON.  WITH THE LOSS OF DAYTIME
HEATING...EXPECT A LULL IN ANY THUNDERSTORM DEVELOPMENT OVERNIGHT.
RENEWED CONVECTION IS EXPECTED IN THE SOUTHERN TIER BY ABOUT 18Z
SATURDAY.

WHILE MAINLY VFR CIGS ARE EXPECTED...ANY PASSING THUNDERSTORM COULD
PRODUCE HEAVY RAIN AND LOWER VSBYS TO MVFR OR IFR FOR A BRIEF TIME.

OUTLOOK...
SUNDAY....MAINLY VFR. A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS.
MONDAY AND TUESDAY...MAINLY VFR. CHANCE OF SHOWERS AND THUNDERSTORMS.

&&

.MARINE...
A RELATIVELY WEAK PRESSURE GRADIENT OVER THE LOWER LAKES WILL KEEP
WIND AND WAVES WELL BELOW SCA CRITERIA TODAY THROUGH TODAY.
THE EXCEPTION  TO THIS GENERAL TREND WILL BE IN THE VICINITY OF
PASSING THUNDERSTORMS WHICH WILL MAY BE ACCOMPANIED BY VERY HEAVY
RAIN AND GUSTY WINDS.

SOUTHWEST WINDS WILL PICK UP A BIT THIS WEEKEND...BUT SCA CONDITIONS
ARE NOT EXPECTED.

&&

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

&&

SYNOPSIS...TJP
NEAR TERM...ZAFF
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...ZAFF
MARINE...TJP

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BUFFALO NY
519 AM EDT FRI JUL 5 2013

NYZ001>008-010>014-019>021-085-060930-
NIAGARA-ORLEANS-MONROE-WAYNE-NORTHERN CAYUGA-OSWEGO-JEFFERSON-LEWIS-
NORTHERN ERIE-GENESEE-WYOMING-LIVINGSTON-ONTARIO-CHAUTAUQUA-
CATTARAUGUS-ALLEGANY-SOUTHERN ERIE-
519 AM EDT FRI JUL 5 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND NORTH CENTRAL NEW
YORK.

.DAY ONE...TODAY AND TONIGHT.

SCATTERED THUNDERSTORMS WILL DEVELOP AGAIN TODAY. THE MOST
WIDESPREAD COVERAGE IS EXPECTED ACROSS WESTERN NY THROUGH EARLY
AFTERNOON BEFORE MORE SCATTERED THUNDERSTORMS DEVELOP THROUGHOUT
THE REGION LATER THIS AFTERNOON WITH DAYTIME HEATING. ANY
THUNDERSTORM MAY PRODUCE VERY HEAVY RAINFALL AND POOR DRAINAGE
FLOODING IN LOCALIZED AREAS.

NO WIDESPREAD SEVERE WEATHER IS EXPECTED...BUT AN ISOLATED STORM
WITH DAMAGING WINDS AND HAIL CANNOT BE RULED OUT.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

SCATTERED THUNDERSTORMS ARE EXPECTED ON A DAILY BASIS THROUGH
EARLY NEXT WEEK. A FEW STORMS MAY PRODUCE VERY HEAVY RAINFALL AND
POOR DRAINAGE FLOODING IN LOCALIZED AREAS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

THIS PRODUCT...ALONG WITH OTHER WATCHES...WARNINGS...ADVISORIES...
AND STATEMENTS ISSUED BY THE NATIONAL WEATHER SERVICE OFFICE IN
BUFFALO CAN BE FOUND ON THE INTERNET AT HTTP://WWW.WEATHER.GOV/BUF

LEZ020-040-041-LOZ042>045-062>065-SLZ022-024-060930-
UPPER NIAGARA RIVER AND BUFFALO HARBOR-
LAKE ERIE NEARSHORE WATERS FROM RIPLEY TO DUNKIRK-
LAKE ERIE NEARSHORE WATERS FROM DUNKIRK TO BUFFALO-
LAKE ONTARIO NEARSHORE WATERS FROM THE NIAGARA RIVER TO HAMLIN BEACH-
LAKE ONTARIO NEARSHORE WATERS FROM HAMLIN BEACH TO SODUS BAY-
LAKE ONTARIO NEARSHORE WATERS FROM SODUS BAY TO MEXICO BAY-
LAKE ONTARIO NEARSHORE WATERS FROM MEXICO BAY TO THE SAINT LAWRENCE
RIVER-
LAKE ONTARIO OPEN WATERS FROM THE NIAGARA RIVER TO HAMLIN BEACH-
LAKE ONTARIO OPEN WATERS FROM HAMLIN BEACH TO SODUS BAY-
LAKE ONTARIO OPEN WATERS FROM SODUS BAY TO MEXICO BAY-
LAKE ONTARIO OPEN WATERS FROM MEXICO BAY TO THE SAINT LAWRENCE RIVER-
SAINT LAWRENCE RIVER FROM CAPE VINCENT TO OGDENSBURG-
SAINT LAWRENCE RIVER FROM OGDENSBURG TO SAINT REGIS-
519 AM EDT FRI JUL 5 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE ERIE...LAKE
ONTARIO AND SAINT LAWRENCE RIVER.

.DAY ONE...TODAY AND TONIGHT.

SCATTERED THUNDERSTORMS WILL DEVELOP AGAIN TODAY. A FEW STORMS MAY
PRODUCE GUSTY WINDS AND LOCALLY HIGHER WAVES. BRIEF DOWNPOURS WILL
LIMIT VISIBILITY AT TIMES.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

SCATTERED THUNDERSTORMS WILL CONTINUE ON A DAILY BASIS THROUGH
EARLY NEXT WEEK. A FEW STORMS MAY PRODUCE GUSTY WINDS AND LOCALLY
HIGHER WAVES. BRIEF DOWNPOURS WILL LIMIT VISIBILITY AT TIMES.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

THIS PRODUCT...ALONG WITH OTHER WATCHES...WARNINGS...ADVISORIES...
AND STATEMENTS ISSUED BY THE NATIONAL WEATHER SERVICE OFFICE IN
BUFFALO CAN BE FOUND ON THE INTERNET AT HTTP://WWW.WEATHER.GOV/BUF

HITCHCOCK

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
1245 PM EDT FRI JUL 5 2013

NYZ003>006-013-014-021-052000-
MONROE-WAYNE-NORTHERN CAYUGA-OSWEGO-LIVINGSTON-ONTARIO-ALLEGANY-
INCLUDING THE CITIES OF...ROCHESTER...NEWARK...FAIR HAVEN...
OSWEGO...GENESEO...CANANDAIGUA...WELLSVILLE
1245 PM EDT FRI JUL 5 2013

...STRONG STORMS WITH HEAVY RAIN...WIND AND SMALL HAIL THIS AFTERNOON...

SCATTERED THUNDERSTORMS DEVELOPING EARLY THIS AFTERNOON ARE
EXPECTED TO BECOME MORE WIDESPREAD LATER TODAY. WHILE NOT ALL
LOCATIONS WILL RECEIVE RAIN...SOME AREAS MAY EXPERIENCE HEAVY
RAIN UNDER SLOW MOVING THUNDERSTORMS. IN ADDITION...SOME OF THESE
STORMS MAY CONTAIN SMALL HAIL AND GUSTY WINDS. BE ON THE LOOKOUT
TO THE SOUTHWEST FOR DEVELOPING STORMS THIS AFTERNOON. HEAD
INDOORS STORMS ARE MOVING YOUR WAY.

ZAFF

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BUFFALO NY
211 PM EDT FRI JUL 5 2013

NYZ006-007-051915-
JEFFERSON NY-OSWEGO NY-
211 PM EDT FRI JUL 5 2013

...STRONG THUNDERSTORM MOVING INTO THE AREA...

* AT 207 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  STRONG THUNDERSTORM CAPABLE OF PRODUCING SMALL HAIL...STRONG GUSTY
  WINDS...AND HEAVY RAIN. THIS STORM WAS LOCATED NEAR OSWEGO...
  AND MOVING EAST AT 30 MPH.

* SOME LOCATIONS AFFECTED BY THE STRONG THUNDERSTORM MAY INCLUDE...
  SCRIBA...
  NINE MILE POINT...
  NEW HAVEN...
  MEXICO...
  PULASKI...
  SANDY CREEK...
  LACONA AND ALTMAR...

THIS STORM HAS THE POTENTIAL TO BECOME SEVERE AND PRODUCE LARGE HAIL
AND/OR DAMAGING WINDS.

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE
INDOORS IMMEDIATELY!

THIS STORM HAS THE POTENTIAL TO PRODUCE VERY HEAVY RAIN...AND COULD
CAUSE LOCALIZED FLOODING OF ROADS AND POOR DRAINAGE AREAS.

LAT...LON 4347 7589 4343 7659 4344 7659 4348 7649
      4353 7642 4354 7636 4352 7635 4354 7624
      4358 7621 4367 7621 4372 7599

REYNOLDS