Tornado and Flash Flooding in Ohio, May 1 to 2, 2007

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
102 PM EDT TUE MAY 1 2007

.AVIATION/18Z-18Z/...
LOW PRES MOVG FM NR SBN EWRD ALG THE SRN SHORE OF LERI THIS EVE WL
PULL A CDFNT TRAILING THE LOW SE ACRS INLAND AREAS FIRST HALF OF
TNGT.  UNSTBL AMS AND SUPPORTING GUD WND SHEAR WL LEAD TO POTENTIAL
FOR STG TO LOCALLY SVR TSRA.  WNDS GUSTING TO 50KT OR MORE ARE
POSSIBLE LATE THIS AFTN THRU EVE. TRYING TO TIME WHEN AND WHERE TSRA
WL OCCUR WL BE TOUGH AS DYNAMICS MAY ALLOW FOR CONVECTION TO DVLP
ALMOST ANYWHERE BUT AT TAF ISSUE TIME WL TRY AND BEST REFLECT SOME
TYPE OF TIMING FM NW TO SE DUE TO PASSAGE OF LOW AND CDFNT. LLVL
MSTR IS SHOWN TO RMN WIDESPREAD OVR AREA LATE TNGT INTO WED MORN
WITH GUIDANCE HINTING AT LOW STRATUS CLDS VERSUS FOG AS WNDS STAY UP
ENUF TO LEAN THE BALANCE TOWARD MORE STRATUS THAN FOG. WL TAKE A
STAB AND GO FOR CIGS OF HI END IFR DURG THIS PD AS THE SHALLOW COOL
AIR MOVS IN. CIGS SHUD START TO BREAK UP BY LATE WED MORN AS AMS
MIXES WITH DRIER AIR ABV THE BNDRY LYR.

&&

.SHORT TERM (THIS AFTERNOON)...
UPDATED FOR TIMING. WILL GO WITH CHC TRW INTO EARLY AFTERNOON THEN
LIKELY FROM MID AFTERNOON ON.

&&

.SHORT TERM/TODAY THROUGH WEDNESDAY NIGHT/...
WARM FRONT ACROSS SRN OH WILL BE MAJOR WX MAKER TDA WITH POTENTIAL
FOR SOME DECENT STORMS LATER IN THE DAY. FIRST THINGS FIRST
THO...LINE OF CONVECTION CONTS TO STRETCH FROM NERN OH ACROSS LERI
AND INTO LOWER MI.  HAS BEEN A SLIGHT DECREASE IN INTENSITY OF THIS
ACTIVITY AND IT APPEARS TO BE SHIFTING OFF TO THE ENE EVER SO
SLOWLY.  AT ANY RATE EXPECT MOST OF IT TO BE GONE BY 12Z OR SO.
SOME MODEL DIFFS TODAY WITH MOVEMENT OF SFC LOW ACROSS NRN OH.  GFS
IS VERY FAST WITH THIS FEATURE WHILE NAM REMAINS SLOWER AND MUCH
MORE CONSISTENT.  GIVEN FLOW ALOFT FEEL NAM MAY BE THE WAY TO GO
TODAY.  WARM FRONT FROM THIS LOW WILL MOVE N ACROSS FORECAST AREA
THIS AFT.  MODELS CONTINUE TO OVERDUE SFC MOISTURE AND PROGS OF SFC
DEWPOINTS IN THE LOW 60S AT 18Z OBVIOUSLY OVERDONE GIVEN FACT YOU
HAVE TO GO AS FAR SW AS ARKANSAS TO FIND SIMILAR DEWPOINTS.  WITH
THAT SAID...FORECASTS OF INSTABILITY AND CAPE TODAY BY BUKFIT ARE
ALSO A LITTLE OVERDONE.  BUT...GIVEN FAIRLY DECENT STRAIT LINE SHEAR
DO EXPECT TSRA TO GET GOING AS FRONT APPROACHES.  COULD BE A FEW
SUPERCELLS TODAY BUT STEEP LAPSE RATES AND FAIRLY UNIDIRECTIONAL
SHEAR PROFILES SUGGEST MORE OF A DAMAGING WIND/LARGE HAIL EPISODE
THIS AFT.  SO...WILL CONT WITH LIKELY WORDING TODAY ALL AREAS AND IN
THE E TONIGHT.  HAVE ADDED SEVERE WORDING TO GRIDS GIVEN SLIGHT RISK
FROM SPC.  TEMPS COULD BE TRICKY TODAY WITH LOW 80S IN THE S AND
UPPER 50S IN NW PA.  DAY CREW WILL HAVE TO WATCH SRN AREAS THIS AFT
AS TEMPS IN SRN OH YDAY WERE VERY WARM.  PRECIP SHOULD WIND DOWN
FROM NW TO SE TONIGHT AS SFC LOW MOVES INTO CENTRAL PA.  DRY AND
RELATIVELY COOL WEATHER FOR THE MIDDLE OF THE WEEK.

&&

.LONG TERM/THURSDAY THROUGH SUNDAY/...
EXTENDED FORECAST CONTINUES TO TREND TOWARD A HIGHLY AMPLIFIED
PATTERN. BUILDING UPPER LEVEL RIDGE BEGINS TO MOVE INTO WESTERN
LAKES THURSDAY WITH UPPER LEVEL LOW NE OF NEW ENGLAND SLOWLY PULLING
OUT. THE RIDGE PROGRESSES SLOWLY INTO THE LOWER LAKES BY MONDAY. AT
SURFACE  CANADIAN HIGH PRESSURE CENTERED OVER HUDSON BAY THURSDAY
WITH RIDGE SOUTH INTO THE EASTERN GREAT LAKES REMAINS OVER THE AREA
THROUGH MONDAY AS THE CENTER OF THE HIGH DRIFTS SOUTH SOUTHEAST
THROUGH THE NORTHEASTERN U.S. AND TO MID ATLANTIC COAST STATES LATE
MONDAY. EXPECTING DRY WEATHER THROUGHOUT THE EXTENDED. TEMPERATURES
WILL INITIALLY AVERAGE LITTLE BELOW NORMAL RISING TO ABOVE BY END
PERIOD AS SOUTHWESTERLY FLOW DEVELOPS AS HIGH MOVES TO THE MID
ATLANTIC COAST. COULD BE COLD ENOUGH THURSDAY/FRIDAY MORNING FOR
SOME FROST IN THE EASTERN AREAS.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.

&&

SHORT TERM...LW/KUBINA
LONG TERM...WCR
AVIATION...ADAMS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CLEVELAND OH
218 PM EDT TUE MAY 1 2007

LEZ145>149-164>169-OHZ010>014-020>023-031>033-038-047-089-PAZ001>003-
021830-
VERMILION TO AVON POINT OH-AVON POINT TO WILLOWICK OH-
WILLOWICK TO GENEVA-ON-THE LAKE OH-GENEVA-ON-THE-LAKE TO CONNEAUT OH-
CONNEAUT OH TO RIPLEY NY-
THE ISLANDS TO VERMILION OH BEYOND 5 NM OF SHORE-
VERMILION TO AVON POINT OH BEYOND 5 NM OF SHORE-
AVON POINT TO WILLOWICK OH BEYOND 5 NM OF SHORE-WILLOWICK TO GENEVA-
ON-THE-LAKE OH BEYOND 5 NM OF SHORE-GENEVA-ON-THE-
LAKE TO CONNEAUT OH BEYOND 5 NM OF SHORE-
CONNEAUT OH TO RIPLEY NY BEYOND 5 NM OF SHORE-LORAIN-CUYAHOGA-LAKE-
GEAUGA-ASHTABULA INLAND-MEDINA-SUMMIT-PORTAGE-TRUMBULL-WAYNE-STARK-
MAHONING-HOLMES-KNOX-ASHTABULA LAKESHORE-NORTHERN ERIE-SOUTHERN ERIE-
CRAWFORD PA-
218 PM EDT TUE MAY 1 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR LAKE ERIE...NORTH CENTRAL
OHIO...NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

THE STORM PREDICTION CENTER HAS INDICATED THAT THERE IS A SLIGHT
RISK FOR SEVERE THUNDERSTORMS TODAY AND THIS EVENING ACROSS
NORTHERN OHIO AND NORTHWESTERN PENNSYLVANIA.

LOW PRESSURE OVER IOWA WILL MOVE ACROSS NORTHERN OHIO THIS
AFTERNOON AND INTO CENTRAL PENNSYLVANIA TONIGHT. A WARM FRONT
EXTENDING SOUTHEAST FROM THE LOW WILL MOVE NORTH ACROSS THE AREA
THIS AFTERNOON. AS THIS HAPPENS...THUNDERSTORMS ARE EXPECTED TO
DEVELOP. A FEW OF THESE STORMS COULD BECOME SEVERE WITH DAMAGING
WINDS AND LARGE HAIL THE MAIN THREAT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED THIS AFTERNOON AND EVENING.

LEZ142>144-162-163-OHZ003-006>009-017>019-027>030-036-037-021830-
MAUMEE BAY TO RENO BEACH OH-RENO BEACH TO THE ISLANDS OH-
THE ISLANDS TO VERMILION OH-
MAUMEE BAY OH TO RENO BEACH OH BEYOND 5 NM OF SHORE-
RENO BEACH TO THE ISLANDS OH BEYOND 5 NM OF SHORE-LUCAS-WOOD-OTTAWA-
SANDUSKY-ERIE OH-HANCOCK-SENECA-HURON-WYANDOT-CRAWFORD-RICHLAND-
ASHLAND-MARION-MORROW-
218 PM EDT TUE MAY 1 2007

...SEVERE THUNDERSTORM WATCH 205 IN EFFECT UNTIL 8 PM EDT THIS
EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR LAKE ERIE...NORTH CENTRAL
OHIO AND NORTHWEST OHIO.

.DAY ONE...THIS AFTERNOON AND TONIGHT

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   SEVERE THUNDERSTORM WATCH

LOW PRESSURE OVER IOWA WILL MOVE ACROSS NORTHERN OHIO THIS
AFTERNOON AND INTO CENTRAL PENNSYLVANIA TONIGHT. A WARM FRONT
EXTENDING SOUTHEAST FROM THE LOW WILL MOVE NORTH ACROSS THE AREA
THIS AFTERNOON. AS THIS HAPPENS...THUNDERSTORMS ARE EXPECTED TO
DEVELOP. A FEW OF THESE STORMS COULD BECOME SEVERE WITH DAMAGING
WINDS AND LARGE HAIL THE MAIN THREAT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED THROUGH THIS EVENING.