000
FXUS63 KIWX 132029
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
429 PM EDT MON MAY 13 2013

.SYNOPSIS...
ISSUED AT 1020 AM EDT MON MAY 13 2013

A RIDGE OF HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE AREA
THIS AFTERNOON AND TONIGHT RESULTING IN CONTINUED DRY CONDITIONS
AND THE BEGINNING OF A MODERATING TEMPERATURE TREND. SOUTHERLY
FLOW WILL DEVELOP ACROSS THE REGION TONIGHT AS THIS HIGH SHIFTS
OFF TO THE EAST...ALLOWING FOR MUCH WARMER CONDITIONS ON TUESDAY
AND WEDNESDAY. A FRONTAL BOUNDARY WILL SLOW ACROSS THE AREA ON
WEDNESDAY...PROVIDING A CHANCE OF SHOWERS AND THUNDERSTORMS
WEDNESDAY AFTERNOON AND NIGHT.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 428 PM EDT MON MAY 13 2013


A STRONG WARM FRONT WILL BEGIN TO LIFT NORTHEAST TONIGHT. AT THE
ONSET...VERY DRY AIR WAS IN THE LOW LEVELS WITH SFC DEW POINTS IN
THE 20S...AND EVEN SOME TEENS. ADDED A SLIGHT CHANCE FOR A SHOWER
OVER FAR NORTH AREAS TONIGHT AND EARLY TUESDAY TO MATCH THE BEST
AREA OF 850 MB THETA E CONVERGENCE WHERE SHOWERS HAVE THE BEST
CHANCE OF FORMING. OTHERWISE...VERY WARM AIR WILL STREAM NORTHEAST
TOMORROW...WITH TEMPS MUCH WARMER TUESDAY. RAISED HIGHS CONSIDERABLY
TUESDAY...ESPECIALLY OVER NORTHEAST AREAS GIVEN 850 MB TEMPS FROM
11C NORTHEAST TO ABOVE 17C OVER FAR WEST AREAS. EXPECT AFTERNOON
TEMPS WILL BE ABLE TO MIX WITH A FULL DRY ADIABATIC RATE FROM 850
MB...YIELDING MID 70S NORTHEAST INTO THE 80S WEST. RAISED HIGHS
ABOUT 2 DEGREES OVER WEST AREAS...BUT AREAS WEST OF HIGHWAY 31 MAY
BE ABLE TO CLIMB IN THE MID TO UPPER 80S...ESPECIALLY FROM LAPORTE
SOUTH TO LOGANSPORT. A LOW LEVEL JET WILL TRANSLATE SOUTHEAST INTO
NW INDIANA AND FAR SW LOWER MICHIGAN EARLY TUESDAY. EXPECT WIND
GUSTS WILL BE HIGHEST EARLY...AND THEN WEAKEN BY EARLY AFTERNOON.
EXPECT WIND GUSTS TO AROUND 30 MPH OVER NW AREAS BY MID TO LATE
MORNING WILL DIMINISH RATHER QUICKLY DURING THE AFTERNOON.

&&

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 428 PM EDT MON MAY 13 2013

AGAIN FEW CHANGES WITH REGARDS TO LATER PERIODS. RATHER DUBIOUS WITH
RESPECT TO SUCH CONTINUAL LONG DURATION OF LOW RANGE CHANCES FOR
CONVECTION MIDWEEK INTO THE WEEKEND...SANS ASCERTAINMENT OF EMBEDDED
DRY PERIODS. NONETHELESS HAVE INTRODUCED AND/OR CONTINUED SOME
MODIFICATIONS IN ATTEMPT AT BETTERMENT. NORTHWEST PACIFIC COASTAL
SYSTEM TO CUT THROUGH HIGHER BELTED CANADIAN CONVEYOR...REACHING
WESTERN ONTARIO EARLY TUESDAY NIGHT. CONVECTION ASSOCIATED WITH THIS
SYSTEM SHOULD REMAIN NORTH OF AREA...FOCUSED ON NORTHERN TERMINUS OF
LOW LEVEL JET...TO PROVIDE FOCUS FOR ASCENT ACROSS EASTERN
MN/WESTERN WI. DECAY ALONG SOUTHERN FRINGE APPEARS LIKELY GIVEN WELL
NORTHERLY PLACEMENT OF CONVERGENT JET FOCUS...THAT LIES OUT EASTWARD
OVERNIGHT THROUGH NORTHERN WI/CENTRAL LOWER MICHIGAN TO SOUTHERN
LAKE HURON...AND COINCIDENT WITH GRADUALLY WITHERING MUCAPE POOL.
HIGH LOW LEVEL CONDENSATION PRESSURE DEFICITS GREATER THAN 100 MB
SHOULD ALSO ADD TO POOR CONVECTIVE MAINTENANCE ALONG SOUTHERN
PERIPHERY DESPITE SERLY STEERING VECTORS. FRONTAL BOUNDARY DIVES
SSEWD INTO SOUTH FORECAST AREA BY EARLY WED AFTERNOON...HOWEVER
TIMING OF PASSAGE RATHER DISJOINTED WITH MID/UPPER SUPPORT...AND AS
SUCH HAVE CONTINUED TREND TOWARDS SLIGHTLY LOWER WED AFTERNOON POPS.
REFOCUS OF UPSTREAM CONVECTIVE SYSTEMS...MORE PROBABLE WELL UPSTREAM
WED EVENING ACROSS CENTRAL MO/SOUTHERN IL...PERHAPS IMPLICATING
SOUTHERN CWA WED NIGHT INTO THU. SUFFICIENT SOUTHWARD SHUNT OF
SFC-8H THETA-E SUGGESTS ALL BUT FAR SOUTHERN/SOUTHWESTERN CWA LIKELY
DRY THU NIGHT INTO FRIDAY. CONTINUED TREND OF LOW AMPLITUDE TROF
FORMATION ACROSS NORTHERN ROCKIES/INTERMOUNTAIN REGIONS INTO EARLY
THIS WEEKEND WITH HEIGHTS BUILDING SLOWLY ACROSS WESTERN GREAT
LAKES...HAVE TRENDED A BIT WARMER AND DRIER WITH GRADUAL EASTERLY
EJECTION OF TROF...PER GENERAL EC/GFS AGREEMENT...NOT LIKELY TO
BRING SURFACE FRONTAL FOCUS AND DECREASED STABILITY FOR MORE CERTAIN
CONVECTION CHANCES UNTIL LATE WEEKEND/EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 133 PM EDT MON MAY 13 2013

SCATTERED STRATOCU FORMED BY THE SPREADING OUT OF CU AT THE BASE OF
THE SUBSIDENCE INVERSION WILL DISSIPATE BY LATE TODAY AS THIS
LAYER WARMS UP AND DRIES OUT. WARM AIR ADVECTION WILL INCREASE
TONIGHT...ALONG WITH MID AND SOME LOWER LEVEL CLOUDS. CONDITIONS
SHOULD REMAIN VFR THROUGH THE PERIOD. AN AXIS OF LOW LEVEL WINDS
WILL TRANSLATE SOUTHEAST INTO NW INDIANA BY 12Z. SOME OF THE
HIGHER MOMENTUM WINDS AT 925 MB SHOULD BE ABLE TO MIX DOWN BY 15Z
WITH GUSTS TO 25 KNOTS AT SBN.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SYNOPSIS...MARSILI/KG
SHORT TERM...SKIPPER
LONG TERM...MURPHY
AVIATION...SKIPPER


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