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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
425 PM EDT MON MAY 4 2015

.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 228 PM EDT MON MAY 4 2015

A FRONTAL SYSTEM IS EXPECTED TO STALL OVER THE AREA TUESDAY...BEFORE 
DISSIPATING BY WEDNESDAY. ANOTHER FRONTAL SYSTEM MAY AFFECT THE AREA 
BY NEXT WEEKEND.

&&

.NEAR TERM /REST OF THIS AFTERNOON AND TONIGHT/...
ISSUED AT 228 PM EDT MON MAY 4 2015

TAIL END OF VORTICITY CENTER THAT IS CURRENTLY MOVING INTO NORTHWEST 
OHIO EXTENDS BACK INTO ILLINOIS. SHORT TERM MODELS SUGGEST THIS 
FEATURE WILL MOVE INTO THE LOCAL AREA BY LATE THIS AFTERNOON AND 
EVENING. SCATTERED CONVECTION MAY DEVELOP NEAR THIS FEATURE AS IT 
MOVES INTO THE AREA. 

THINK THE BETTER CHANCES FOR MORE ORGANIZED SHOWER/THUNDERSTORM 
ACTIVITY WILL BE LATE TONIGHT OVER THE NORTHERN ZONES AS THE LOW 
LEVEL JET INCREASES. MODELS SUGGEST THE JET WON/T BE TOO 
IMPRESSIVE...BUT IT APPEARS IT WILL BE IN THE RIGHT SPOT FOR GOOD 
POTENTIAL FOR PRECIPITATION DEVELOPMENT. WILL GO WITH LIKELY POPS 
OVER THE NORTH FOR MAINLY LATE TONIGHT...TAPERING TO CHANCE POPS 
FARTHER SOUTH.

THE GFS MOS LOWS TONIGHT LOOK REASONABLE BASED ON LOW LEVEL 
THICKNESSES...SO ONLY MINOR ADJUSTMENTS PLANNED.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
ISSUED AT 228 PM EDT MON MAY 4 2015

MODEL DATA SUGGEST FRONTAL ZONE OFF TO THE NORTH MAY SAG INTO THE 
NORTHERN OR CENTRAL ZONES BY TUESDAY EVENING BEFORE WASHING OUT BY 
WEDNESDAY UNDER BUILDING UPPER RIDGE. CONVECTIVE POTENTIAL NEAR THE 
FRONT SHOULD DIMINISH WITH TIME AS HEIGHTS RISE. WILL KEEP SOME 
CHANCE POPS GOING FOR TUESDAY AND TUESDAY EVENING...MAINLY OVER THE 
CENTRAL AND NORTHERN ZONES. 

SOME OF THE MODEL DATA CONTINUE TO SUGGEST A POTENTIAL FOR WIDELY 
SCATTERED DIURNAL TYPE CONVECTION BOTH WEDNESDAY AND THURSDAY. 
APPEARS CONVECTIVE TEMPERATURES SHOULD EASILY BE REACHED BOTH 
DAYS...BUT LAPSE RATES TAIL OFF BY THEN AS MID LEVELS WARM. WILL 
CONTINUE WITH A DRY FORECAST AFTER TUESDAY NIGHT FOR NOW.

DON/T HAVE TOO MUCH OF A PROBLEM WITH THE GFS TEMPERATURES GUIDANCE 
IN THE LATER PERIODS BASED ON PROGGED LOW LEVEL THICKNESSES.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 241 PM EDT MON MAY 4 2015

WARM AND INCREASINGLY UNSETTLED WEATHER EXPECTED FOR THE WEEKEND
AND INTO EARLY NEXT WEEK AS THE UPPER LEVEL FLOW REMAINS HIGHLY
AMPLIFIED ACROSS THE CONTINENTAL U S.

COASTAL SYSTEM OFF THE SOUTHEAST STATES AND STRONG UPPER LOW IN
THE FOUR CORNERS WILL MAINTAIN BROAD RIDGE OVER THE OHIO VALLEY
INTO THE WEEKEND. THE RIDGE WILL SLOWLY FLATTEN AND EVOLVE INTO A
MOIST SOUTHWEST FLOW INTO EARLY NEXT WEEK AS THE INFLUENCE OF THE
ATLANTIC COAST SYSTEM IS LOST AND THE WESTERN UPPER LOW TRACKS
NORTHEAST INTO THE UPPER MIDWEST. THIS WILL ENABLE A FRONTAL
BOUNDARY TO SAG INTO THE REGION OVER THE WEEKEND WITH INCREASING
CHANCES FOR THUNDERSTORMS.

SCATTERED CONVECTION WILL DEVELOP FRIDAY NIGHT AND SATURDAY...WITH
THE GREATEST POTENTIAL FOR STORMS SUNDAY AND MONDAY AS A STRONG LOW
PRESSURE SYSTEM TRACKS INTO THE GREAT LAKES. HIGHS IN THE 80S WILL
PERSIST THROUGH SUNDAY...WITH POTENTIAL FOR WARMEST DAY ON FRIDAY
UNDER THE RIDGE. AS CLOUDS AND CONVECTION INCREASE ACROSS THE OHIO
VALLEY...HIGHS WILL SLIDE BACK INTO THE 70S OVER MUCH OF THE
REGION BY NEXT MONDAY. LOWS WILL RANGE FROM THE UPPER 50S TO MID
60S THROUGHOUT THE EXTENDED.

&&

.AVIATION /DISCUSSION FOR 042100Z KIND TAF UPDATE/...
ISSUED AT 1248 PM EDT MON MAY 4 2015

MINOR TWEAKS MADE TO KIND TAF TO BETTER MATCH CURRENT CONDITIONS.
NO OTHER CHANGES ARE NEEDED AT THIS TIME.

PREVIOUS AVIATION DISCUSSION FOLLOWS...
RESTRICTIONS POSSIBLE WITHIN CONVECTION...OTHERWISE VFR EXPECTED.

SHOWERS HAVE DIMINISHED AT ALL TERMINALS EARLY THIS AFTERNOON AS
A SUBTLE WAVE ALOFT SHIFTS EAST. SKIES WILL BRIGHTEN OVER THE NEXT
FEW HOURS WITH SATELLITE IMAGERY SHOWING PREDOMINANTLY THIN
MID/HIGH LEVEL CLOUDS EXTENDING BACK TO NEAR THE MISSISSIPPI
RIVER. AS THE AIRMASS DESTABILIZES BY LATE AFTERNOON...EXPECT VFR
CU FORMATION ALONG WITH SCATTERED CONVECTION DEVELOPING OVER THE
FORECAST AREA. PRIMARY IMPACTS WILL BE NEAR AND NORTH OF I-70...BUT
WILL CARRY VCTS MENTION AT ALL SITES FROM 20-22Z THROUGHOUT THE
EVENING AS ALL HI-RES DATA CAPTURING LATE DAY CONVECTIVE
REDEVELOPMENT. COULD SEE SOUTHWEST WIND GUSTS TO NEAR 20KTS AT
TIMES INTO EARLY EVENING.

INSTABILITY WILL DIMINISH ONCE AGAIN WITH SHOWERS AND EMBEDDED
THUNDER PERSISTING OVERNIGHT AS CONVECTIVE CLUSTER SLATED TO
ORGANIZE OVER THE MID MISSISSIPPI VALLEY THIS EVENING MIGRATES
INTO THE NORTHERN FORECAST AREA AFTER MIDNIGHT. FRONTAL BOUNDARY
OVER NORTHERN INDIANA WILL BEGIN TO LIFT BACK NORTH LATE
TONIGHT...WITH PRECIPITATION EVENTUALLY SHIFTING NORTH OF BOTH
KHUF AND KIND BETWEEN 06Z AND 12Z. IMPACTS AT KLAF HOWEVER MAY
LINGER THROUGH DAYBREAK TUESDAY. LIGHT SOUTHERLY FLOW OVERNIGHT
WILL INCREASE TO 10-15KTS FROM THE SOUTHWEST ON TUESDAY.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE. 

&&

$$

SYNOPSIS...JAS
NEAR TERM...JAS
SHORT TERM...JAS
LONG TERM....RYAN
AVIATION...RYAN/JH

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