[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 272001
SWODY1
SPC AC 271959

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0159 PM CST SUN NOV 27 2005

VALID 272000Z - 281200Z

THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 30 E
ELD 35 SE TXK 10 N DEQ 10 NNW FSM 15 SSW JLN 20 WNW EMP 10 E MHK 10
NNW FLV 40 WNW COU 20 NNE VIH 40 NNW POF 10 WSW JBR 55 ENE PBF 30 E
ELD.

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 45 S
BPT 25 NW UTS 40 N PRX 25 WSW MKO 10 S TUL PNC 20 E P28 30 W HUT 25
ENE RSL 30 SW LNK 20 NE DNS 45 NE ALO 25 SE LNR 40 WNW CGX 25 NNE
DNV 20 NNE HOP 20 SSW CBM 65 SSE 7R4.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 55 ENE SSI OGB 35 NW
FLO 10 WNW FAY 15 W OAJ 75 ESE ILM.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 ESE CRP 30 SE CLL
15 NNE CRS 35 SSW MLC 25 SSE CQB 35 ESE END 25 W END 35 SW AVK 20
NNE GAG 40 SSW DDC 25 N GCK 20 E LBF 15 WNW MHE 15 SSW VVV 25 S DLH
20 N CMX 25 E TVC JXN 25 S MIE 15 WSW BWG 15 E TCL 40 WNW ABY 30 SW
VLD 40 SSW CTY.

...THERE IS A MDT RISK OF SVR TSTMS OVER MUCH OF AR...SRN AND WRN
MO...AND ERN KS...

...THERE IS A SLGT RISK OF SVR TSTMS FROM E TX/LA NWD TO IA/IL...

...E TX/LA NWD ACROSS ERN OK/KS...AR...AND MO...
RAPID DEEPENING OF THE SURFACE LOW HAS COMMENCED EARLY THIS AFTN
WITH A 984MB CENTER OVER CNTRL KS.  THE DRYLINE HAS MIXED EWD AND AT
MID-AFTN EXTENDED FROM THE LOW SWD ACROSS ERN OK TO NCNTRL/CNTRL TX.
 A COLD FRONT WAS ACCELERATING ACROSS NWRN OK AND THE TX S PLAINS. 
A PERSISTENT WARM SECTOR CONFLUENCE ZONE HAS MOVED INTO THE ARKLATEX
REGION.

THE LOW SHOULD SLOWLY MOVE TOWARD SERN NEB/NWRN MO/NERN KS THROUGH
THIS EVENING AS THE UPPER LOW BEGINS TO TURN NEWD...THEN ACCELERATE
NEWD INTO THE CORN BELT BY MORNING AS THE SYSTEM BECOMES VERTICALLY
STACKED. THE COLD FRONT WILL OVERTAKE THE DRYLINE...AS IT MOVES
ENEWD ACROSS THE OZARKS AND INTO THE MS VLY LATER TONIGHT.

TWO PRIMARY REGIONS OF SEVERE TSTMS APPEARS IMMINENT...ONE OVER THE
CNTRL PLAINS AND THE OTHER FARTHER S ACROSS THE ARKLATEX REGION. 
THIS SCENARIO FOLLOWS THE VERY PERSISTENT WRF-4KM GUIDANCE FROM THE
PAST COUPLE OF DAYS.

1.  CNTRL PLAINS:  TSTMS HAVE ALREADY INITIATED VCNTY/NE OF THE
SURFACE LOW AND DRYLINE AND ALONG THE NOSE OF STEEPER LOW-LEVEL
LAPSE RATES FROM CNTRL KS SWD INTO NCNTRL OK AT MID-AFTN. 
NEODESHA...LAMONT AND HILLSBORO PROFILERS INDICATE THE STORMS ARE
DEVELOPING ALONG THE NWRN EDGE OF 40-45 KT VERTICAL SHEAR AND ISOLD
CELLS HAVE SHOWN SUPERCELL CHARACTERISTICS.

GIVEN ORIENTATION OF THE DRYLINE...ARCING NWWD INTO THE SURFACE
LOW...2-6KM MEAN WIND VECTORS REMAIN SOMEWHAT NORMAL TO THE
BOUNDARY.  THUS...AS THE TSTMS INTENSIFY DOWNSTREAM ACROSS ERN KS
INTO WRN MO...POTENTIAL FOR DISCRETE CELLS AND SHORT-LINE SEGMENTS
WILL EXIST.  LOW-LEVEL WIND PROFILES HAVE BACKED OWING TO PRESSURE
FALLS OVER CNTRL KS...AND ARE BECOMING MORE FAVORABLE FOR
TORNADOES...ESPECIALLY WITH THE MORE DISCRETE SUPERCELLS THAT MANAGE
TO MOVE OFF THE DRYLINE.  OTHERWISE...VERY STEEP MID-LEVEL LAPSE
RATES WILL SUPPORT LARGE HAIL AND DAMAGING WINDS.

ACTIVITY SHOULD EVOLVE INTO A BROKEN SQUALL LINE OVERNIGHT AND MAY
JOIN WITH NRN-EXTENT OF TSTMS DEVELOPING OVER THE LWR MS VLY. 
DAMAGING WINDS...ISOLD TORNADOES AND HAIL MAY OCCUR AS FAR E AS IL
AND SRN IA LATER TONIGHT.

2.  SRN MO...AR...ERN TX...LA: LOW-LEVEL WINDS HAVE BEEN VEERING
SUBSTANTIALLY WITH DRYING OCCURRING RAPIDLY JUST BEHIND THE WARM
SECTOR CONFLUENCE ACROSS THE ARKLATEX THROUGH MID-AFTN.  PRESENCE OF
INCREASED PRESSURE FALLS SUGGEST THAT THE UPSTREAM W TX MID-LEVEL
IMPULSE MAY BE AFFECTING THE REGION.  WARM SECTOR HAS BECOME MORE
UNSTABLE AS TEMPERATURES WARM AND LOWER 60S DEW POINTS NOSE NWD INTO
THE AR/SRN MO...WEAKENING CINH OBSERVED ON THE 18Z LITTLE ROCK
SOUNDING.  EXPECT TSTMS TO INITIATE ALONG THIS BOUNDARY FROM SWRN AR
INTO EXTREME NERN TX AND ALONG THE MAIN DRYLINE ALONG THE AR/OK
BORDER THROUGH LATE AFTN.

STRONG VERTICAL SHEAR SUGGESTS SUPERCELLS WILL BE LIKELY AND GIVEN
CROSS-BOUNDARY MEAN FLOW VECTORS...DISCRETE CELLS WILL EXIST.  SOME
OF THESE CELLS WILL EVENTUALLY EVOLVE INTO LINE SEGMENTS WITH
DAMAGING WINDS /A FEW SIGNIFICANT WIND EVENTS POSSIBLE/. 
OTHERWISE...TORNADOES WILL BE A THREAT WITH THE MORE DISCRETE
STORMS...WITH ONE OR TWO STRONG TORNADOES POSSIBLE.

THIS ACTIVITY WILL LIKELY JOIN TSTMS DEVELOPING ACROSS MO LATER
TONIGHT...REACHING PARTS OF WRN TN...WRN MS AND CNTRL LA LATER
TONIGHT WITH THE THREATS FOR DAMAGING WINDS...ISOLD TORNADOES AND
HAIL CONTINUING.

..RACY.. 11/27/2005

...NOTICE...
THE STATION RELATIVE POINTS IN THIS PRODUCT WILL BE
DISCONTINUED ON 14 FEBRUARY 2006 BUT WILL REMAIN AVAILABLE
IN THE FOLLOWING PRODUCTS:

   WMO HEADER:       AWIPS ID:
   WUUS01            PTSDY1
   WUUS02            PTSDY2
   WUUS03            PTSDY3

A SERVICE CHANGE NOTICE ...SCN05-39... PROVIDES DETAILS
ON THE TRANSITION. FOR ADDITIONAL DETAILS SEE THE FOLLOWING
WEB ADDRESS USING LOWER CASE LETTERS:
WWW.NWS.NOAA.GOV/OM/NOTIF.HTM