342
FXUS63 KIWX 052324
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
724 PM EDT SAT JUL 5 2008
AVIATION
SIMILAR SET UP TO LAST NIGHT WITH HIGH PRESSURE OVER THE AREA AND
LIGHT WINDS. SOME INTERESTING DEW POINT BOUNDARIES SEEN IN
OBSERVATIONS WITH SOME VERY DRY POCKETS AND OTHER HIGHER MOISTURE
POCKETS. WITH CLEAR SKIES AND LIGHT WINDS...MVFR BR POSSIBLE AGAIN
TONIGHT. CONTINUED WITH PREVIOUS TAF TRENDS OF MVFR VIS FOR A FEW
HOURS LATE TONIGHT. OTHERWISE VFR ON SUNDAY WITH FEW CLOUDS.
SHORT TERM
HIGH PRESSURE ESTABLISHED AT SFC PROVIDING A FINE SUNNY DAY FOR THE
CWA WITH HIGH CLOUDS TO OUR SOUTH ASSOCIATED WITH DEEPENING H5 TROF
AND CU DEVELOPMENT BEGINNING OVER SOUTHERN COUNTIES WHERE DWPTS ARE
HIGHEST. DEEP SFC LOW LOCATED OVER MANITOBA SLIDING WEST WHILE
TRAILING COLD FRONT MOVING INTO DAKOTAS AND STRONG UPPER FLOW
SITUATED OFF TO THE NORTH. TEMPS RUNNING SIMILAR TODAY...JUST A
COUPLE OF DEGREES WARMER IN MOST PLACES EXCEPT FOR SE COUNTIES
WHERE IT WAS CLOUDY/COOLER YESTERDAY. LIGHT WINDS TURNING
SOUTHERLY OVERNIGHT WITH MOSTLY CLEAR SKIES SHOULD ONCE AGAIN ALLOW
FOR SOME PATCHY FOG IN THE EARLY MORNING HOURS.
MODELS CLOSE OFF H5 LOW SUNDAY WITH GOOD AGREEMENT ON LOCATION TO
OUR SE NEAR KY/OH. CWA REMAINS NW OF LOW/BACK SIDE OF H5 TROF IN
AREA OF SUBSIDENCE RESULTING IN ANOTHER NICE DRY SUNDAY. TEMPS
WILL WARM ANOTHER FEW DEGREES UNDER JULY SUN. SOUTHERLY LL FLOW
INCREASES MOISTURE THROUGH THE DAY...WITH SUNDAY NIGHT LOW TEMPS
SEVERAL DEGREES WARMER AS A RESULT. AS LOW OVER CANADA MOVES EAST
ASSOCIATED SFC FRONT WILL DIP INTO THE UPPER MIDWEST. CONVECTION
IS INDICATED IN MODELS AHEAD OF THE FRONT WHICH 12Z RUNS TRY TO
SNEAK INTO NORTHERN ILLINOIS/SOUTHERN WISCONSIN BY MONDAY
MORNING...BUT AT THIS TIME BELIEVE IT WILL HOLD TO THE WEST
THROUGH THIS PERIOD EVEN IF THE MORE EASTERLY PROPAGATION OCCURS
LONG TERM
VERY LITTLE ADJUSTMENT NEEDED...MODELS HAVE BEEN FAIRLY CONSISTENT
EARLY IN THE PERIOD...AND ARE STARTING TO BE SLIGHTLY MORE
CONSISTENT LATER. HIGHER CONFIDENCE MON AND TUES (4 OF 5)...WITH
NEAR AVG CONFIDENCE FROM WED ON INTO THE WEEKEND (3 OF 5).
MONDAY THROUGH TUESDAY...
CONTINUED CONCERNS OF POSSIBLE MCS ACTIVITY AS FRONTAL BOUNDARY
PUSHES EAST TOWARDS THE REGION...AND WEAK RIDGING NUDGES INTO THE
REGION ALLOWING FOR WNW OR WEST FLOW ACROSS THE REGION. DECENT
INSTABILITY SEEN THROUGH THE AFTERNOON/EARLY EVENING MONDAY ALLOWING
FOR MODERATE CAPES NEAR 1500-2000 J/KG...AND THE BIT OF CAPPING
LOOKING TO BREAK IN THE LATE AFTERNOON MOST LIKELY. WILL ALTER
WORDING TO SCTD AS THE SHOWERS/TSTORMS WILL MOST LIKELY BE HIT AND
MISS. MAIN CONCERN WOULD BE THREAT OF LOCALLY HEAVY RAINFALL WITH
HIGH PWATS NEAR 1.7 INCHES AND DECENT WARM CLOUD LAYER AROUND 11.5 K
FT.
FRONTAL BOUNDARY PUSHES INTO THE REGION TUESDAY. SIGNAL THERE FOR
ALL THE INGREDIENTS NECESSARY FOR STORMS...BOUNDARY AS A
TRIGGER...SIGNIFICANT MOISTURE WITH PWATS NEARING 2 INCHES...AND
INSTABILITY WITH HEATING PRODUCING CAPES NEAR 2000-2500 J/KG BY LATE
AFTERNOON/EARLY EVENING AND DECENT MID LVL SPEED MAX PUSHING THRU
THE AREA. BUMPED UP THE POPS TO VERY LOW END LIKELY FOR THE TUESDAY
18Z TO 00Z WEDNESDAY TIMEFRAME. MODEST UNIDIRECTIONAL FLOW ALONG THE
BOUNDARY...WARM CLOUD LAYERS AOA 13 KFT...DECENT LOW LVL JET...MAIN
CONCERN WILL BE TRAINING STORMS PRODUCING LARGER RAINFALL TOTALS AND
POSSIBLE FLOODING. WITH THAT SAID...AS PREVIOUSLY MENTIONED IN THE
LAST DISCUSSION WET MICROBURSTS CAN NOT BE ENTIRELY RULED OUT. WILL
MENTION BOTH OF THESE THREATS IN THE HWO.
WEDNESDAY THROUGH SATURDAY...
SFC HIGH PRESSURE WILL START TO WORK INTO THE REGION...WITH
TROUGHINESS DEVELOPING ACROSS THE NORTHEASTERN CONUS AND GREAT
LAKES. TRENDED TEMPS COOLER FOR THE WED-THU PERIOD...THEN WARMING AS
THE SFC HIGH PUSHES EAST AND WARMER SOUTHERLY FLOW STRENGTHENS
FRIDAY INTO THE WEEKEND AND MORE ZONAL FLOW DEVELOPS WITH
SIGNIFICANT RIDGING ACROSS THE SOUTHEASTERN CONUS AND MUCH OF THE
OHIO VALLEY. H850 TEMPS AROUND 8 TO 10C WED/THU CLIMB TO ABOUT 15C
FOR FRIDAY...AND PUSH NEAR 18 TO 20C BY SATURDAY.
HAVE THE ENTIRE PERIOD DRY WITH LITTLE SIGNAL FOR PRECIP IN ANY
MODEL...THE ONLY POSSIBLE DEBATE MAY BE HOW FAST THE FRONT PUSHES
THRU TUESDAY NIGHT. IF SLOWER SOLUTION WERE TO DEVELOP THEN A SLIGHT
CHC OF PRECIP MAY EXIST FOR THE FIRST HALF OF WEDNESDAY...
EXPERIENCE IS THAT THESE SUMMER SYSTEMS CAN BE TRICKY AS THEY CAN
STALL A BIT MORE NORTHERLY THAN EXPECTED SOME TIMES AS THEY PUSH
INTO A SE CONUS RIDGE...STRONG MODEL SUPPORT HERE THAT THIS WILL NOT
BE THE CASE AND PUSH WELL INTO THE OH AND TN VLY BY EARLY WED
MORNING.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
SHORT TERM...LUDINGTON
LONG TERM...SCHOTT
AVIATION...LASHLEY
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