Area Forecast Discussion Issued by NWS Indianapolis, IN
000
FXUS63 KIND 222254
AFDIND
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
655 PM EDT WED MAY 22 2013
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 325 PM EDT WED MAY 22 2013
AN AMPLIFIED UPPER PATTERN SHOULD KEEP CHANCES FOR RAIN
AND SOME THUNDERSTORMS IN THE FORECAST THROUGH THURSDAY BUT THEN
HIGH PRESSURE BUILDING IN WILL DRY THINGS OUT INTO THE WEEKEND.
SMALL CHANCES FOR THUNDERSTORMS RETURN BY SATURDAY NIGHT AND REMAIN
IN THE FORECAST THROUGH THE EXTENDED WITH THE STRONG UPPER RIDGE TO
THE WEST BREAKING DOWN AND A POSSIBLE PATTERN TRANSITION SETTING UP.
TEMPERATURES WILL BE BELOW NORMAL ON THE BACK SIDE OF THE UPPER LOW
FROM THURSDAY THROUGH MONDAY AND THEN REBOUND.
&&
.NEAR TERM /THIS EVENING AND TONIGHT/...
ISSUED AT 325 PM EDT WED MAY 22 2013
RADAR MOSAIC SHOWS WIDELY SCATTERED SHOWERS OVER EASTERN INDIANA
WITH A LINE OF SHOWERS AND THUNDERSTORMS STRETCHING FROM SOUTH OF
TERRE HAUTE TO NORTH OF LAFAYETTE AT 19Z. THIS LINE IS MOVING
NORTHEAST AROUND 30 MPH AND SHOULD CONTINUE ALONG AT THAT
RATE...POSSIBLY STILL REMAINING OVER THE EASTERN COUNTIES AT 0Z.
THERE ARE ALSO SCATTERED SHOWERS OCCURRING OVER CENTRAL ILLINOIS
BEHIND THE LINE...BUT THESE ARE DIURNAL IN NATURE AND SHOULD START
DISSIPATING AFTER SUNSET. THUS WILL TREND POPS UP WITH THE LINE
ACROSS THE AREA THIS AFTERNOON/EVENING AND BACK DOWN AFTER IT
PASSES. WILL KEEP ISOLATED THUNDER GOING IN THE EAST FOR A FEW HOURS
TONIGHT WITH TIMING OF THE LINE STILL PLACING IT NEARBY UNTIL AFTER
0Z. SEVERE THREAT APPEARS TO BE BETTER EAST OF THE FORECAST
AREA...ALTHOUGH AT THIS TIME STILL REMAIN WITH EAST HALF IN SLIGHT
RISK.
FOR TEMPERATURES GENERALLY WENT NEAR CONSENSUS...WHICH WAS A LITTLE
WARMER THAN MAV OR MET...WITH BROKEN CLOUD COVER EXPECTED AND COLD
ADVECTION NOT AMPING UP UNTIL THURSDAY MORNING.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
ISSUED AT 325 PM EDT WED MAY 22 2013
MODELS ARE IN DECENT AGREEMENT SO WILL GENERALLY USE A CONSENSUS.
UPPER TROUGH AXIS IS FORECAST TO MOVE THROUGH AROUND MIDDAY
THURSDAY. LOOKS LIKE A VORT MAX WILL BE ROTATING THROUGH THE TROUGH
AXIS AS IT MOVES THROUGH...BUT THIS HAPPENS MORE IN THE MORNING IN
THE GFS AND A BIT LATER IN THE NAM. WITH COLD AIR ALOFT MOVING
THROUGH AS WELL...EXPECT TO SEE SOME STRATOCU DEVELOPMENT ALONG WITH
SCATTERED SHOWERS DURING THE DAY THURSDAY. MODELS SHOW SOME
INSTABILITY WORKING INTO THE EASTERN COUNTIES IN THE LATE MORNING TO
AFTERNOON SO ADDED SOME ISOLATED THUNDER THERE. BY EVENING THE AXIS
WILL BE OFF TO THE EAST AND ANY PRECIPITATION SHOULD COME TO AN
END. DRY WEATHER WILL THEN BE IN PLACE THROUGH SATURDAY. ONE CAVEAT
TO THIS IS THAT THE NAM IS SHOWING WHAT LOOKS LIKE AN MCS DEVELOPING
OVER MINNESOTA FRIDAY NIGHT AND RIDING THE RIDGE DOWN INTO THE AREA
SATURDAY MORNING...BUT THE GFS DOESN/T SHOW A SIMILAR FEATURE AND
THINK PREDICTABILITY OF SUCH A FEATURE THIS FAR OUT IS PRETTY SLIM.
FOR TEMPERATURES GENERALLY THOUGHT A MOS CONSENSUS SHOULD WORK OUT
FINE...WITH COLD ADVECTION THURSDAY AND THURSDAY NIGHT BEHIND THE
COLD FRONTAL PASSAGE BUT THEN RELATIVELY STABLE 850 MB TEMPERATURES
FROM FRIDAY ON. TEMPERATURES WILL GENERALLY BE BELOW CLIMATOLOGY IN
THE 60S THURSDAY THROUGH SATURDAY...WITH LOWS BOTTOMING OUT IN THE
LOW TO MID 40S THURSDAY NIGHT AND FRIDAY NIGHT.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 142 PM EDT WED MAY 22 2013
GOOD CORRESPONDENCE BETWEEN MODELS AND MOS DERIVED FROM THEM. IN
PARTICULAR...ENSEMBLE SPREAD IN THE MEN PRODUCT IS QUITE LOW. NO
REASON TO MAKE MAJOR CHANGES IN CENTRAL REGION INITIALIZATION.
&&
.AVIATION /DISCUSSION FOR 230000Z TAF ISSUANCE/...
ISSUED AT 655 PM EDT WED MAY 22 2013
MOSTLY VFR CONDITIONS WILL DROP TO MVFR CEILINGS TOWARDS SUNRISE
THURSDAY. A RATHER UNSETTLED WEATHER PATTERN WILL BE THE RULE AS
LOW PRESSURE MOVES EAST ACROSS THE GREAT LAKES. MOST OF THE SHOWERS
AND THUNDERSTORMS HAVE MOVED OFF TO THE EAST...BUT WIDELY SCATTERED
LIGHT SHOWERS WILL BE THE RULE OVERNIGHT. HOWEVER CHANCES ARE TOO LOW
TO MENTION IN TAFS.
OF MORE SIGNIFICANT WILL AREAS OF MVFR CEILINGS WILL LIKELY SPREAD
ACROSS OUR REGION TOWARDS SUNRISE THURSDAY AS A LARGE AREA OF
WRAP AROUND MOISTURE OVER THE UPPER MIDWEST MOVES OUR WAY AS THE
UPPER TROUGH ROTATES EASTWARD. MODEL SOUNDINGS INDICATE CEILINGS OF
1-2 THOUSAND ARE POSSIBLE. WITH THE UPPER TROUGH MOVING THROUGH AND
SOME DAYTIME HEATING...SCATTERED SHOWERS WILL ALSO BE THE RULE AND
WILL MENTION VCSH IN ALL TAFS THURSDAY.
WINDS WILL BE 8 KNOTS OR LESS OVERNIGHT AND THEN NORTHWEST 15 TO 20
KNOTS BY MIDDAY THURSDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....JK
AVIATION...JH
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