Area Forecast Discussion
Issued by NWS Cleveland, OH

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FXUS61 KCLE 021340
AFDCLE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
ISSUED BY NATIONAL WEATHER SERVICE BUFFALO NY
940 AM EDT WED SEP 2 2015

.SYNOPSIS...
HIGH PRESSURE WILL MOVE SLOWLY NORTHEAST ACROSS THE OHIO VALLEY
THROUGH THURSDAY. THE HIGH WILL EVENTUALLY BECOME BY HIGH PRESSURE
NORTH OF MAINE BY FRIDAY. AN INVERTED TROUGH OF LOW PRESSURE WILL
EXTEND NORTHEAST ACROSS THE AREA SATURDAY INTO SUNDAY. THE HIGH
PRESSURE NORTH OF MAINE WILL SLIDE SOUTH ALONG THE EASTERN
SEABOARD AND DOMINATE THE LOCAL AREA DURING THE SECOND HALF OF THE
LABOR DAY WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...12Z SOUNDINGS ACROSS THE LOWER GREAT LAKES REGION ALL
SHOW A LOW LEVEL INVERSION WITH AMPLE CAPE ABOVE ABOUT 950MB...YET
WITH LITTLE SHEAR. A WEAK CUTOFF AREA OF CIRCULATION OVER
SOUTHEAST OH IS PROVIDING ENOUGH LIFT FOR CONVECTION NEAR THE
VERY WEAK COMMA HEAD OF THIS FEATURE. THIS AREA IS BARELY WITHIN
THE CLE FORECAST AREA AND SHOULD BE OF LITTLE/LESSENING INTEREST
AS THE CIRCULATION MOVES SLOWLY EAST THIS AFTERNOON.

ANOTHER SEPARATE AREA OF CONVECTION IS OVER FAR NW OH/SE MI THIS
MORNING. THIS AREA IS A LITTLE MORE CONCERNING WITH SOME
CONCENTRATED AREAS OF THUNDERSTORMS FORMING THROUGHOUT THE
MORNING. WILL INCREASE THE PROBABILITY OF PRECIPITATION A TOUCH
OVER THE TOLEDO AREA AND POINTS S/SE FOR INTO THE AFTERNOON HOURS
FOR SCATTERED/CHANCE CONVECTION.

PREVIOUS UPDATE...
OVERALL...MINOR UPDATE TO ADJUST HOURLY TEMPERATURES. ERIE PA FOLKS
I MADE A BLUNDER AND DID NOT INCREASE TEMPERATURES HIGH ENOUGH
RIGHT ALONG THE LAKE SHORE. I INCREASED MAXIMUM TEMPERATURES FOR
TODAY TO THE MIDDLE 80S. I DONT ANTICIPATE THE LAKE BREEZE WILL
KEEP TEMPERATURES DOWN.

A WEAKENING OUTFLOW BOUNDARY IS MOVING EAST ACROSS SOUTHERN LOWER
MICHIGAN AND AND INDIANA. A THUNDERSTORM DEVELOPED ALONG THE
OUTFLOW OVER MICHIGAN. I WILL KEEP A SLIGHT CHANCE IN THIS MORNING
FOR THE WESTERN PORTIONS OF THE FORECAST AREA TO ACCOUNT FOR THE
OUTFLOW. ACTIVITY TODAY WILL LIKELY BE THE RESULT OF OUTFLOW
BOUNDARIES THAT DEVELOP AS A RESULT OF OTHER CONVECTION IN THE
AREA.

PREVIOUS DISCUSSION...
TIME TO TAKE OUT THE RUBBER STAMP AND USE IT FOR THE FORECAST OVER
THE NEXT SEVERAL DAYS. SUMMER PATTERN SET UP OVER THE REGION WITH
UPPER LEVEL RIDGE IN PLACE KEEPING HIGH PRESSURE OVER THE AREA
TODAY. THE HIGH IS PROGGED TO MOVE SLOWLY NORTHEAST OUT OF THE OHIO
VALLEY. THE COMBINATION OF THE SURFACE HIGH AND UPPER LEVEL RIDGE
WILL PRODUCE SOME SUBSIDENCE. HOWEVER...AN UPPER LEVEL POSITIVE
VORTICITY MAXIMUM WILL SLIDE SOUTHEAST ACROSS THE WEST CENTRAL AND
SOUTH CENTRAL PORTIONS OF OHIO TODAY. THIS FEATURE WILL SPREAD SOME
POSITIVE VORTICITY ADVECTION ACROSS THE FORECAST AREA AND AID IN THE
DEVELOPMENT OF SHOWERS AND THUNDERSTORMS. ONCE AGAIN...UPPER LEVEL
WINDS HARDLY EXISTS. MAXIMUM WINDS UP TO 35000 FEET AVERAGING AROUND
7 TO 10 KNOTS TODAY.  THIS EXPLAINS THE VERY SLOW MOVEMENT IF ANY OF
THE STORMS LAST EVENING. ACTUALLY...THE STORMS MORPHED THEIR MOTION
RATHER THAN MOVED. I ANTICIPATE THE ACTIVITY THAT DOES DEVELOP
TODAY WILL DO THE SAME WITH LOCALLY HEAVY RAINERS EXPECTED. THE
NORTHEAST PORTION OF THE FORECAST AREA WILL LIKELY ESCAPE AND
REMAIN DRY THROUGH THE DAY.

HERE IS WHERE THE RUBBER STAMP COMES IN. PROVIDED PRECIPITATION
HOLDS OFF UNTIL PEAK HEATING OF THE DAY...MAXIMUM TEMPERATURES TODAY
WILL LIKELY BE VERY SIMILAR TO YESTERDAY. SO WILL NOT DEVIATE TOO
MUCH FROM YESTERDAYS HIGH TEMPERATURES AS WE REMAIN IN THE SAME AIR
MASS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
UPPER LEVEL PATTERN REALLY GETS AMPLIFIED OVER THE NEXT SEVERAL DAYS
AS OVERALL PATTERN SHIFTS ON THE WEST COAST OF THE LOWER 48. DEEP
DIGGING UPPER LEVEL TROUGH DIVES INTO THE WEST COAST OVER THE NEXT
FEW DAYS CAUSING THE UPPER LEVEL RIDGE IN THE EASTERN UNITED STATES
TO AMPLIFY. WHAT DOES THIS MEAN FOR OUR LOCAL AREA...MORE HIGH
PRESSURE...WARM TEMPERATURES...AND MUGGY CONDITIONS TO PRODUCE
SCATTERED SHOWERS AND THUNDERSTORMS THROUGH THE REST OF THE WORK
WEEK.

ONCE THE SURFACE HIGH PRESSURE OVER THE LOCAL AREA BECOMES ABSORBED
IN THE SURFACE HIGH NORTH OF MAINE...AN INVERTED SURFACE TROUGH WILL
DEVELOP OVER THE LOCAL AREA SATURDAY INTO SUNDAY. MOISTURE FLUX FROM
THE GULF OF MEXICO WILL BE CUT OFF AS THE HIGH PRESSURE NORTH OF
MAINE BUILDS SOUTH ALONG THE EASTERN SEABOARD. THIS WILL LIMIT THE
THREAT FOR SHOWERS AND THUNDERSTORMS ONCE WE GET INTO THE EARLY PART
OF THE WEEKEND. ONCE AGAIN...MORE OF THE SAME WARM TEMPERATURES AND
FAIR WEATHER FOR SATURDAY AND SATURDAY NIGHT.

TEMPERATURES THROUGH THE PERIOD ARE GOING TO BE VERY SIMILAR EACH
DAY. AS A MATTER OF FACT...I THINK THIS IS THE FIRST I HAVE SEEN
THIS BUT THE LATEST MAV GUIDANCE SAYS EXACTLY THE SAME MIN/MAX
TEMPERATURES FOR THEIR RESPECTIVE PERIODS INDICATING WHAT I HAVE
BEEN SAYING ALL ALONG...NO CHANGE. I DONT REALLY SEE ANY CHANGE IN
THE AIR MASS THROUGH THE MIDDLE PART OF NEXT WEEK.

&&

.LONG TERM /SUNDAY THROUGH TUESDAY/...
NOT MANY CHANGES TO THE LONG TERM THIS MORNING.  THE
WEEKEND IS STILL LOOKING WARM AND HUMID. THERE COULD BE A FEW POP
UPS EACH DAY BUT GIVEN LACK OF FORCING IT IS IMPOSSIBLE TO KNOW WHEN
AND WHERE THEY WILL OCCUR.  COVERAGE SHOULD BE UNDER 10 PERCENT SO
WILL KEEP THE DRY FORECAST GOING.  DIFFERENCES IN THE MODELS BEGIN
TO SHOW UP BY THE END OF THE PERIOD.  THE ECMWF REMAINS QUICKER
BRINGING A COLD FRONT ACROSS THE AREA ON TUESDAY.  THE GFS DOESN`T
HAVE THIS FRONT ARRIVING TILL TUESDAY NIGHT.  THE PREVIOUS FORECAST
ALREADY HAD A CHANCE MENTION FOR BOTH PERIODS AND GIVEN THE
UNCERTAINTY WILL JUST CONTINUE WITH THAT FOR NOW.  TEMPS BOTH
SUNDAY AND MONDAY SHOULD TOP OUT IN THE UPPER 80S MOST AREAS WITH
SLIGHTLY COOLER READINGS ON TUESDAY.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
A WEAK UPPER LEVEL DISTURBANCE HAS MOVED INTO SOUTHEAST OHIO AND
THIS HAS CAUSED A FEW SHOWERS TO DEVELOP. LATEST GUIDANCE KEEPS
THIS ACTIVITY GOING FOR A FEW HOURS AND THEN DISSIPATES IT BEFORE
IT GETS EAST OF I-71. AFTER THAT THE BIG QUESTIONS REMAIN AS TO
HOW MUCH MORE PRECIP THERE WILL BE THIS AFTERNOON. IT SHOULD BE
MORE ACTIVE THAN THE PAST COUPLE OF DAYS BUT COVERAGE SHOULD STILL
BE 30 PERCENT OR LESS. AS A RESULT WILL GO WITH A VICINITY
MENTION IN THE WEST THIS MORNING AND THEN DRY THE REMAINDER OF THE
PERIOD. A BROKEN WEAK LINE MAY MAKE IT THROUGH KTOL THIS
MORNING...WILL UPDATE THE WESTERN TAFS AS NECESSARY WHILE CONVECTION
EVOLVES ALONG A WEAK BOUNDARY.  STEERING FLOW IS MINIMAL TODAY SO
ANY STORMS THAT DO DEVELOP WILL BE SLOW MOVERS. MORE CUMULUS IS
EXPECT BY MIDDAY. LIGHT SW FLOW WILL BECOME W TODAY WITH AN
ONSHORE NORTHERLY COMPONENT AT BOTH KERI AND KCLE.

OUTLOOK...AREAS OF NON VFR EACH MORNING IN FOG AND HAZE. ISOLATED
THUNDERSTORMS MAY DEVELOP EACH AFTERNOON/EVENING.

&&

.MARINE...
LIGHT FLOW WILL CONTINUE ON THE LAKE MOST OF THE PERIOD.
THIS WILL RESULT IN ONSHORE FLOW DEVELOPING ON THE NEARSHORE WATERS
DURING THE AFTERNOON. A BACK DOOR COLD FRONT IS STILL EXPECTED TO
DROP SOUTH ACROSS THE LAKE THURSDAY.  THIS WILL CAUSE THE FLOW TO
BECOME EAST TO NORTHEAST FOR A TIME.  SPEEDS SHOULD REMAIN UNDER 15
KNOTS SO DO NOT THINK WE WILL NEED ANY HEADLINES.  THE FLOW WILL
RETURN TO THE SOUTH OVER THE WEEKEND.  GIVEN THE LACK OF PRESSURE
GRADIENT...SPEEDS MOST OF THE TIME WILL BE UNDER 10 KNOTS.

&&

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

&&

$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY/ZAFF
SHORT TERM...LOMBARDY
LONG TERM...KUBINA
AVIATION...KUBINA/ZAFF
MARINE...KUBINA



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