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000
FXUS63 KILX 130506
AFDILX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1206 AM CDT THU JUN 13 2013

.DISCUSSION...
ISSUED 853 PM CDT WED JUN 12 2013
EVOLUTION OF STORMS QUITE A BIT DIFFERENT THAN PREVIOUSLY
FORECAST. COLD POOL NOT DEVELOPING AS EXPECTED...AND CORFIDI
VECTORS MAINTAINING A MORE EASTERLY MOTION TO THE SYSTEM OVERALL.
SCT TS PASSING ACROSS THE NORTH AND NORTHEAST...BUT THE STRONGER
DYNAMICS REMAIN WELL TO THE NORTH...EVEN THOUGH THE REMAINDER OF
ILX STILL HAS PLENTY OF INSTABILITY. WILL KEEP POPS IN FOR THE
OVERNIGHT HOURS...SHOULD ANY SHOWERS BE ABLE TO DEVELOP CLOSER TO
THE FRONT ITSELF...OR ANY WEAK BOUNDARIES ASSOCIATED WITH THE
SHOWERS TO THE NORTH. FOR NOW...SPC IS REDUCING THE OVERALL SEVERE
WEATHER RISK FOR MUCH OF THE CENTRAL PORTIONS OF THE STATE. MINOR
UPDATES OUT MOMENTARILY...BUT WILL KEEP POPS IN FOR SCT TS THROUGH
TONIGHT.



&&

.AVIATION...
ISSUED 1155 PM CDT WED JUN 12 2013
NOT MUCH OF A SHIFT IN THE FORECAST OVERALL. MAINTAINING VFR FOR A
BIT WITH VCTS MENTION IN PIA CMI AND BMI CLOSER TO THE UPPER WAVE
PASSING THROUGH. COLD FRONT PASSING AS WELL...WILL RESULT IN A
WIND SHIFT THAT IS ALREADY SLOWLY VEERING THE WINDS TO MORE NWRLY
FOR ALL TERMINALS. NORTHERLY WINDS FOR TOMORROW...WITH A STOUT
PRESSURE GRADIENT KEEPING THE WINDS UP A BIT TOMORROW. CLOUDS
LATER TONIGHT...BEHIND THE FRONT ARE DROPPING TO LOW MVFR/IFR
CUSP. CIGS AROUND 1000-1500 FT...BREAKING UP WITH THE
SUNRISE...AND RETURNING TO VFR AND GUSTY NRLY WINDS TOMORROW. PREV
CONCERN FOR DROPPING VIS A BIT LESS OF A CONCERN WITH LIMITED LLVL
MOISTURE AND DROPPING DWPTS.


HJS
&&

.PREV DISCUSSION...
ISSUED 237 PM CDT WED JUN 12 2013

MAIN FOCUS TODAY IS THE MAJOR CONVECTIVE DEVELOPMENT OF SEVERE
WEATHER...DERECHO TYPE EVENT POSSIBLE.

SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT.
MORNING UPPER AIR DEPICTED SD SHORTWV WITH UPPER LEVEL JET PUSHING
EAST BENEATH THE WAVE. MOISTURE CHANNEL IMAGERY SHOWS THE SD UPPER
CIRCULATION HAD MOVED EAST TO EASTERN SD BY 19Z AND WAS TURNING A
LITTLE TO THE ESE NOW. DRYING BENEATH THE WAVE IN IMAGERY SUGGESTS
SHORTWV AXIS FROM CENTRAL IA TO NORTHEAST KS...MOVING RAPIDLY NOW
TO EAST. SURFACE DATA ANALYSIS THIS AFTERNOON HAS LOW CENTER IN
CENTRAL IA AND WARM FRONT EXTENDED TO THE EAST OVER NORTHERN
IL...WITH COLD FRONT TO SOUTHWEST INTO KS. SPC MESOSCALE ANALYSIS
SHOWS 4000 MUCAPES IN WARM SECTOR OVER CENTRAL IL...HOWEVER ILX
18X SPECIAL SOUNDING DISPLAYS CAP STILL PRESENT THAT WILL INHIBIT
CONVECTIVE DEVELOPMENT. CONVERGENCE SHOWING UP IN SURFACE DATA IN
IA IN AREA OF LOW AND TO EAST ALONG WARM FRONT. EXPECT DEVELOPMENT
OF CONVECTION TO OCCUR NEXT FEW HOURS IN CONVERGENCE AREA WITH
POSSIBLE DISCRETE STORMS IN THE DEVELOPMENT PHASE. COOL POOL FROM
STORMS SHOULD CONGEAL ACTIVITY INTO LINEAR SYSTEM THAT WILL THEN
TRACK TO THE ESE AND THEN SE TOWARD THE MOST UNSTABLE AIR THIS
EVENING. DAMAGING WINDS...LARGE HAIL POSSIBLE...WITH A FEW
TORNADOES ON EMBEDDED CIRCULATIONS DUE TO THE STRONG SHEER PRESENT
IN THIS SYSTEM. BEST POSSIBLE TORNADIC DEVELOPMENT AREA WILL BE
OVER NORTHERN IL THOUGH...DUE TO WARM FRONTAL BOUNDARY LOCATION.
SOUTHWEST EXTENT OF THE CONVECTION WILL BE INCREASED TO THE
SOUTHWEST OF THE CONVECTIVE LINE...AS CONVERGENCE ON THE COLD
FRONT WILL INCREASE WITH THE FURTHER EASTWARD APPROACH OF THE
UPPER LEVEL SHORTWAVE INTO THE EVENING.

SYSTEM WILL MOVE EAST OF IL BY LATE TONIGHT...LEAVING DRY CONDITIONS


&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$