[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 161259
SWODY1
SPC AC 161258

DAY 1 CONVECTIVE OUTLOOK CORR 1
NWS STORM PREDICTION CENTER NORMAN OK
0758 AM CDT SUN APR 16 2006

VALID 161300Z - 171200Z

...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF IL...WRN KY AND SW
IND...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS VLY TO THE NC
CST...

CORRECTED FOR PARTS OF STATES IN MDT RISK

...SYNOPSIS...
WRN IA CLOSED LOW EXPECTED TO MOVE ESE ACROSS THE REMAINDER OF THAT
STATE TODAY...BEFORE ACCELERATING ESE ACROSS IL/IND TONIGHT AS THE
SYSTEM WEAKENS AND IS REABSORBED INTO THE WLYS.  ASSOCIATED SURFACE
LOW SHOULD REACH THE QUINCY AREA BY 00Z SUNDAY AS TRAILING PACIFIC
COLD FRONT/DRY LINE SWEEPS E INTO S CNTRL IL.  FRONTAL ZONE
EXTENDING ESE FROM THE LOW INTO KY AND NC SHOULD BECOME MORE SHARPLY
DEFINED TODAY AND LIKELY WILL SHOW LITTLE OVERALL MOVEMENT.

...SRN WI/NRN IL TO LWR OH VLY --- NEAR TERM...
WARM ADVECTION/UPLIFT ON DOWNWIND SIDE OF SLIGHTLY ELEVATED
INSTABILITY AXIS HAS SUPPORTED DEVELOPMENT OF SCATTERED STORMS OVER
PARTS OF IL SWD INTO WRN KY IN THE PAST 2 HRS. SUFFICIENT ELEVATED
INSTABILITY IS PRESENT TO SUPPORT SOME HAIL /MUCAPE TO 800 J PER
KG/.  BUT STORM MERGERS...AND MOVEMENT OF FORCING MECHANISM NEWD
BEYOND LLJ/INSTABILITY AXIS...SUGGEST THAT OVERALL SEVERE THREAT
WILL BE LIMITED /REF MCD 523/.

...MID MS INTO LWR OH VLY...
SURFACE HEATING AND MID LEVEL COLD ADVECTION/ASCENT IN EXIT REGION
OF SPEED MAX ROUNDING BASE OF IA LOW EXPECTED TO FOSTER STORM
DEVELOPMENT BY EARLY AFTERNOON NEAR SURFACE LOW OVER SE IA/WRN IL
AND PERHAPS NE MO.  DEEP SHEAR INVOF THIS INITIAL ACTIVITY WILL NOT
BE ESPECIALLY STRONG.  BUT STEEP LOW TO MID LEVEL LAPSE RATES AND
ENHANCED LOW LEVEL VEERING PROFILES NEAR STATIONARY FRONT SUGGEST
POTENTIAL FOR HAIL AND POSSIBLY A BRIEF TORNADO OR TWO.

WITH CONTINUED HEATING...EXPECT THAT STORMS WILL DEVELOP SWD ALONG
COLD FRONT OVER FAR ERN MO...AND ESE ALONG STATIONARY FRONT INTO IL.
THIS DEVELOPMENT WILL OCCUR AS AFOREMENTIONED JET STREAK ELONGATES
AND RESULTS IN STRENGTHENING OF DEEP SHEAR EWD ALONG STATIONARY
FRONT INTO SRN IL/SW IND AND WRN KY.  BOUNDARY LAYER MOISTURE
AVAILABILITY WILL BE A BIT LIMITED /AVERAGE SURFACE DEWPOINTS AROUND
60 F/ BY COMPARISON TO MORE WIDESPREAD SEVERE WEATHER EVENTS.  BUT
GIVEN STRONG HEATING...SUFFICIENT MOISTURE WILL BE PRESENT TO YIELD
SBCAPE OF 1500-2000 J/KG.  WITH 40+ KT DEEP WNWLY SHEAR ORIENTED
PARALLEL TO STATIONARY FRONT...A CONCENTRATED AREA OF SUSTAINED
SUPERCELLS APPEARS LIKELY.  THESE STORMS WILL HAVE THE POTENTIAL TO
PRODUCE LARGE HAIL/HIGH WIND AND  TORNADOES...ESPECIALLY IN S CNTRL
IL INTO WRN KY/SW IND. INCREASED CIN WITH SWD EXTENT SHOULD
PROHIBIT STORM DEVELOPMENT SWD ALONG COLD FRONT INTO AR/TN.

BY THIS EVENING EXPECT THAT THE STORMS WILL HAVE COALESCED INTO A
COMPLEX...WITH EMBEDDED SUSTAINED STORMS/POSSIBLE SUPERCELLS IN
KY/SRN IND.  COUPLED WITH INCREASINGLY UNIDIRECTIONAL WIND FIELD AND
ORIENTATION OF LOW LEVEL INSTABILITY AXIS EXTENDING TO THE ESE...THE
SETUP COULD SUPPORT EVOLUTION INTO A FORWARD-PROPAGATING SQUALL
LINE.  IF SUCH A SYSTEM DEVELOPS...AN ATTENDANT THREAT FOR HIGH WIND
AND HAIL COULD REACH THE WRN SLOPES OF THE CNTRL/SRN APPALACHIANS
EARLY MONDAY.

...WV/SW VA INTO NC...
A SECONDARY FOCUS FOR STRONG...MAINLY DIURNAL STORM DEVELOPMENT WILL
EXIST ALONG AND JUST S OF ERN EXTENSION OF SAME FRONT AFFECTING THE
OH VLY.  THE DIFFUSE FRONT SHOULD BECOME STATIONARY FROM SRN WV INTO
ERN NC LATER TODAY.  LARGE SCALE FORCING FOR ASCENT WILL REMAIN WEAK
AT BEST...AND INITIATION MAY BE TIED MORE TO OROGRAPHIC SOURCES THAN
TO FRONT.  BUT COMBINATION OF STRONG SURFACE HEATING WITH RELATIVELY
STEEP MID LEVEL LAPSE RATES AND 40-50 KT DEEP UNIDIRECTIONAL WNWLY
SHEAR WILL BE FAVORABLE FOR WIDELY SCATTERED SUSTAINED
STORMS/SUPERCELLS WITH HAIL/HIGH WIND.

...NRN GRT BASIN TO NRN HI PLNS...
BROAD...FAIRLY STRONG E PACIFIC TROUGH WILL MOVE INLAND THIS PERIOD
AS EMBEDDED SHORTWAVE IMPULSE NOW ENTERING NRN CA CONTINUES E INTO
NV.  ELSEWHERE...ASCENT WILL ALSO INCREASE OVER ERN MT/WRN ND...IN
ENTRANCE REGION OF DOWNSTREAM JET STREAK OVER SASKATCHEWAN.
COMBINATION OF SURFACE HEATING WITH INCREASING LARGE SCALE ASCENT
SHOULD FOSTER STORM DEVELOPMENT ALONG ASSOCIATED COLD FRONT FROM THE
NRN HI PLNS SWWD INTO THE NRN GRT BASIN.  THERMODYNAMIC AND 
KINEMATIC ENVIRONMENT SUGGEST POTENTIAL FOR A FEW STORMS WITH SEVERE
OR NEAR SEVERE WINDS ALONG THIS CORRIDOR LATER TODAY THROUGH EARLY
TONIGHT.

..CORFIDI.. 04/16/2006