National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCLE 200757
AFDCLE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
357 AM EDT MON MAY 20 2013

.SYNOPSIS...
-- Changed Discussion --
AN UPPER RIDGE ACROSS THE AREA TODAY WILL MOVE EAST TONIGHT. A
WEAK WARM FRONT WILL MOVE ACROSS THE REGION TODAY. AN AREA OF LOW
PRESSURE OVER THE NORTHERN PLAINS WILL SLOWLY PROGRESS EASTWARD
ACROSS THE GREAT LAKES REGION THROUGH MID WEEK. THE AIRMASS WILL
BECOME INCREASINGLY MOIST AND UNSTABLE AS THIS FEATURE APPROACHES.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
TODAY IS A TOUGH FORECAST. THE HRRR AND RUC/RAP MODELS HAVE BEEN
FORECASTING A NARROW BAND OF SHOWERS/THUNDERSTORMS TO DEVELOP OVER
EASTERN INDIANA EARLY THIS MORNING AND THEN MOVE EAST. AT 3 AM EDT
THE ILN 88D WAS INDICATING A FINE LINE OVER SE INDIANA. AS EACH HOUR
HAS GONE ON THE MODELS ARE DELAYING THE DEVELOPMENT AND INTENSITY OF
THE PRECIPITATION. NOW THEY DON`T HAVE ANY PRECIPITATION DEVELOPING
ON THIS LINE UNTIL AROUND 8 OR 9 AM MAINLY FROM CLE SOUTH.
SOME OF THE RADAR FORECAST OUTPUT FROM SPC STORM-SCALE
ENSEMBLE OF OPPORTUNITY MODELS ARE ALL OVER THE PLACE FOR
TODAY...SOME WITH NO SHOWER OR THUNDERSTORM DEVELOPMENT IN THE
FORECAST AREA AND SOME WITH A LITTLE DEVELOPMENT. THE 4KM WRF NMM
MODEL HAS SOME ISOLATED SHOWERS DEVELOPING. CONFIDENCE IS LOW IN
THIS BECAUSE OF SO MUCH RIDGING ALOFT...BUT WILL FORECAST A CHANCE
OF SPRINKLES MAINLY THIS AM AS THIS LINE MOVES THROUGH.  WILL
MONITOR THIS AND UPDATE AS NEEDED.

ANY FOG THAT DEVELOPS THROUGH DAYBREAK SHOULD NOT BE SIGNIFICANT
ENOUGH TO BE MENTIONED IN THE ZONES/GRIDS.

OTHER THEN THIS NOT EXPECTING ANY SHOWERS AND THUNDERSTORMS TO
DEVELOP TODAY...THEY SHOULD HOLD OFF UNTIL AFTER 6 PM. NOT EXPECTING
MUCH OF A LAKE BREEZE AS THE GRADIENT WILL BE TOO STRONG. ERIE MAY
GET A LAKE BREEZE FOR A TIME THIS AFTERNOON. WENT ON THE WARMER SIDE OF
GUIDANCE FOR HIGHS BECAUSE OF AN INCREASING SOUTHWEST FLOW AND
WARMER AIR ALOFT.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
-- Changed Discussion --
THE UPPER LOW AND SURFACE LOW NOW OVER THE NORTHERN PLAINS WILL
MOVE SLOWLY EAST AND BE OVER THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT. IN THE MEANTIME THE CHALLENGE IS FIGURING OUT THE
SHOWER AND THUNDERSTORM CHANCES.

FOR TONIGHT THE UPPER RIDGE MOVES EAST AND WITH SOME MOISTURE AND A
WEAK IMPULSE MOVING THROUGH KEPT CHANCE POPS MAINLY OVER THE
NORTHERN PORTION OF THE FORECAST AREA. THE RADAR FORECAST FROM THE
4KM WRF NMM 00Z MODEL SEEMS REASONABLE WITH SOME THUNDERSTORMS
BRUSHING THE NORTHERN PORTION OF THE FORECAST AREA.

FOR TUESDAY CHANCE POPS MOST AREAS BUT DID CONTINUE LIKELY POPS
EXTREME NORTHWEST OHIO. ON THE EDGE ABOUT THAT BASED ON THE LACK
OF MOISTURE ALOFT. THE AIRMASS IS UNSTABLE. FOR TUESDAY NIGHT
AGAIN...CHANCE POPS AS THE AIRMASS IS BECOMING MORE MOIST AND
CONTINUED UNSTABLE. FOR WEDNESDAY INTO THURSDAY WITH THE FRONT
GETTING CLOSE WEDNESDAY AND THEN SAGGING THROUGH ON THURSDAY
LIKELY POPS AT TIMES LOOKS VERY GOOD. AS WE GET CLOSER WE WILL BE
ABLE TO PUT MORE RESOLUTION INTO THE FORECAST.

USED A BLEND OF GUIDANCE AND THE PREVIOUS FORECAST FOR THE HIGHS AND
LOWS. THE HIGHS TUESDAY AND WEDNESDAY ARE TRICKY IF WE GET TOO MUCH
CONVECTION AND CLOUDS THIS WILL HAVE A TREMENDOUS IMPACT ON THE
TEMPERATURES.

RAINFALL AMOUNTS ARE EXPECTED TO BE LESS THAN INCH FOR THIS
WEEK...EXCEPT LOCALLY HIGHER AMOUNTS IN SOME THUNDERSTORMS.

THE AIRMASS FOR TONIGHT WILL BE SOMEWHAT DRY ALOFT AND THIS WILL
LEAD TO POSSIBLE SIGNIFICANT DOWNDRAFTS AS PER THE DELTA THETA E...WILL
MENTION THAT IN THE HAZARDOUS WEATHER OUTLOOK. WILL ALSO MENTION
RISK OF SEVERE TUESDAY THROUGH WEDNESDAY NIGHT ESPECIALLY.
-- End Changed Discussion --

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
-- Changed Discussion --
LITTLE CHANGE IN THE EXTENDED.  BOTH GFS AND ECMWF MOVE HIGH
PRESSURE OVER THE AREA FRIDAY...WHICH LINGERS THROUGH THE WEEKEND.
EXTENDED LOOKS DRY WITH MORE SEASONAL TEMPS THROUGH THE WEEKEND.
-- End Changed Discussion --

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
WITH DEW POINTS CREEPING INTO THE 60S DO EXPECT MORE MVFR BR THIS
MORNING...BUT WIND SHOULD HELP IT FROM BEING TOO WIDESPREAD. SHORT
TERM MODELS NOT IN AGREEMENT ON THE TSRA IN ILLINOIS...LATEST HRR
MOVE TSRA INTO NW OH BY 12Z. FOR NOW WILL ONLY ADD VCTS TO TOL AND
FDY SINCE CONFIDENCE IS LOW AT THIS TIME.


.OUTLOOK...NON VFR PROBABLE IN SHOWERS/THUNDERSTORMS MONDAY
EVENING THROUGH THURSDAY.

&&

.MARINE...
-- Changed Discussion --
PREDOMINATELY A SOUTH TO SOUTHEAST FLOW TODAY ALTHOUGH COULD SEE A
WEAK LAKE BREEZE EAST HALF FOR A FEW HOURS.  EXPECT SOUTHWEST FLOW
TO DEVELOP TOMORROW AHEAD OF NEXT SYSTEM.  MODELS IN GOOD AGREEMENT
PUSHING THE NEXT FRONT THROUGH ON THURSDAY.  WITH NORTH TO NORTHEAST
FLOW DEVELOPING BEHIND THE SYSTEM WILL APPROACH SMALL CRAFT ADVISORY
CRITERIA.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...KIELTYKA
NEAR TERM...KIELTYKA
SHORT TERM...KIELTYKA
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB