AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
1005 PM EDT MON MAY 20 2013
.SYNOPSIS...
THE AIR MASS WILL BECOME INCREASINGLY MOIST AND UNSTABLE THROUGH MID
WEEK AS AN AREA OF LOW PRESSURE OVER THE UPPER MIDWEST SLOWLY
APPROACHES THE REGION. THIS LOW PRESSURE SYSTEM WILL TRACK THROUGH
THE EASTERN GREAT LAKES LATE WEDNESDAY AND PUSH A COLD FRONT SOUTH
ACROSS THE AREA. HIGH PRESSURE WILL RETURN FOR THE END OF THE
WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
CLUSTER OF THUNDERSTORMS FROM LOWER MI HAVE MOVED EAST INTO
ONTARIO. CLEAR/MOSTLY CLEAR SKIES ACROSS NRN OH/NW PA FOR NOW.
FOCUS NOW TURNS TO CONVECTION ACROSS IL. MESO MODELS BRING THIS
INTO IND...WITH LITTLE REACHING WESTERN OH AROUND 6 OR 8 AM. HAVE
DRY OVERNIGHT FOR EASTERN TWO THIRDS OF THE AREA...BUT KEPT SOME
PRECIPITATION CHANCES ALONG THE I-75 CORRIDOR ESPECIALLY TOWARD
MORNING. AT A MINIMUM DEBRIS CLOUDS WILL MAKE IT INTO THE WEST.
SOME STRATUS MAY DEVELOP ACROSS THE EAST...BUT LESS CONFIDENT
ABOUT THAT. MILD TONIGHT WITH CLOUDS LATE AND A LIGHT SOUTH
BREEZE. THEREFORE HAVE RAISED LOWS A DEGREE OR TWO.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
UPPER LEVEL RIDGE AXIS WILL SHIFT EAST OF THE AREA ON TUESDAY AS THE
APPROACHING LOW PRESSURE SYSTEM MOVES INTO THE WESTERN LAKES REGION.
SHORTWAVE ENERGY IS EXPECTED TO EJECT OUT OF THE TROUGH TOWARDS THE
AREA AND HELP TO INITIATE CONVECTION. MODELS ALSO INDICATE A LOW
LEVEL JET WILL CLIP NW OHIO ON TUESDAY MORNING AND CONVECTION COULD
MOVE INTO THE AREA FROM THE WEST DURING THE MORNING. THERE IS SOME
UNCERTAINTY AS TO HOW ACTIVITY WILL EVOLVE...IF IT WILL CONTINUE
EASTWARD DOWN WIND OF THE LLJ OR IF WAIT UNTIL WE DESTABILIZE TO
INITIATE. CLOUD COVER COULD BE A LIMITING FACTOR FOR DESTABILIZATION
BUT EXPECT WE WILL STILL SEE STRONG WITH TEMPERATURES IN THE LOW 80S
AND DEWPOINTS IN THE 60S. A SPEED MAX AT 500MB WILL ALSO MOVE ACROSS
NW OHIO AND HELP TO SUPPORT CONVECTION. GIVEN THE FAVORABLE SHEAR
AND MODERATE INSTABILITY THE WESTERN HALF OF THE FORECAST AREA IS IN
A SLIGHT RISK FOR SEVERE WEATHER. EXPECTING THE PRIMARY THREAT TO BE
WIND GIVEN THE STRONG FLOW ALOFT. FREEZING LEVELS ARE HIGH NEAR
13.5KFT SO ONLY THE STRONGEST STORMS WILL BE ABLE TO PRODUCE HAIL
AND THE SURFACE FRONT REMAINS TO OUR WEST SO LOW LEVEL SHEAR WILL
NOT BE VERY FAVORABLE FOR TORNADOGENESIS. WITH THAT SAID...A LOW
CHANCE DOES STILL REMAIN FOR BOTH HAIL AND TORNADOES. SHEAR IS
CONSIDERABLY LOWER ACROSS THE EASTERN CWA AND STORM MOTION WILL BE
TO THE NORTHEAST AT ABOUT 35 MPH SO THE SEVERE THREAT WILL BE
LOWER...MAINLY EAST OF I-71.
EXPECTING A LULL IN SHOWERS AND THUNDERSTORMS ON TUESDAY NIGHT SO
WILL JUST HOLD ONTO A CHANCE POP. AN UPPER LEVEL JET WILL ROUND THE
BASE OF THE TROUGH TUESDAY NIGHT WITH THE TROUGH AXIS SWINGING
NORTHEAST TOWARDS THE OHIO VALLEY ON WEDNESDAY. CLOUD COVER IS AGAIN
IN QUESTION BUT LARGE SCALE ASCENT WILL BE STRONGER ON WEDNESDAY AND
EXPECT WIDESPREAD SHOWERS AND THUNDERSTORMS DURING THE DAY. THERE IS
AGAIN A SLIGHT RISK OF SEVERE STORMS ACROSS NEARLY THE ENTIRE
FORECAST AREA WITH BETTER INSTABILITY FOCUSED ACROSS THE EAST.
THE LOW PRESSURE SYSTEM WILL MOVE NORTHEAST THROUGH THE CENTRAL
GREAT LAKES ON WEDNESDAY AND FINALLY PUSH A COLD FRONT SOUTH ACROSS
THE AREA WEDNESDAY NIGHT AND THURSDAY. INSTABILITY AXIS WILL BE TO
OUR EAST FINALLY BY THURSDAY SO ONLY CARRIED THUNDERSTORMS IN THE
SOUTHERN COUNTIES WITH HIGHS NEAR TO JUST SLIGHTLY BELOW NORMAL.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
BY THE START OF THE LONG TERM PERIOD...HIGH PRESSURE IS EXPECTED TO
BE SITUATED OVER THE CENTRAL GREAT LAKES. THIS WILL RESULT IN DRY
NORTHERLY FLOW FOR THE AREA FOR THE ENTIRE WEEKEND. THE ENTIRE FOUR
DAY LONG TERM PERIOD SHOULD BE DRY. TEMPS WILL STRUGGLE TO GET OUT
OF THE MIDDLE 60S ON FRIDAY AND OUT OF THE UPPER 60S BOTH SATURDAY
AND SUNDAY. READINGS SHOULD RETURN TO CLOSE TO NORMAL ON MONDAY AS
A WARM FRONT APPROACHES FROM THE SOUTH.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
DECIDED TO KEEP THE TAF FORECASTS DRY TONIGHT. CANNOT RULE OUT A
SHOWER/STORM POPPING UP OR MOVING IN FROM THE WEST BUT THE ODDS
APPEAR LOW. WOULD RATHER CONCENTRATE THE THUNDERSTORMS IN THE TAF
FORECASTS FOR TUESDAY AFTERNOON WHEN THEY SEEM MORE LIKELY. EARLY
MORNING MVFR FOG AND HAZE LIKELY TUESDAY MORNING. IFR OR MVFR
STRATUS IS POSSIBLE AS WELL TUESDAY MORNING BUT DECIDED TO LIMIT
IT TO EXTREME NE OH/NW PA WHERE IT WOULD SEEM MOST LIKELY. THE
GUSTY SOUTH WIND WILL DIMINISH THIS EVENING AND RESUME AGAIN
TUESDAY MORNING.
.OUTLOOK...NON VFR PROBABLE IN SHOWERS/THUNDERSTORMS WEDNESDAY AND
THURSDAY.
&&
.MARINE...
SOUTH TO SOUTHWEST FLOW WILL CONTINUE ON THE LAKE TILL A COLD FRONT
CROSSES THE LAKE SOMETIME EARLY THURSDAY. SPEEDS SHOULD MAINLY BE
UNDER 15 KNOTS TILL THE FRONT ARRIVES. ONSHORE FLOW COULD DEVELOP ON
THE NEARSHORE WATERS BOTH TUESDAY AND WEDNESDAY. STRONG TO SEVERE
STORMS APPEAR POSSIBLE BOTH TUESDAY AND WEDNESDAY. BOATERS WILL
NEED TO REMAIN ALERT. SMALL CRAFT ADVISORIES APPEAR LIKELY FOR
THURSDAY AND FRIDAY WITH STRONG NORTHWEST FLOW BEHIND THE FRONT.
SOME SHOWERS ARE LIKELY ON THURSDAY. FRIDAY AND SATURDAY WILL BE
DRY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC/OUDEMAN
SHORT TERM...KEC
LONG TERM...KUBINA
AVIATION...KOSARIK
MARINE...KUBINA
