[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 220540
SWODY1
SPC AC 220539

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1139 PM CST SAT JAN 21 2006

VALID 221200Z - 231200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 60 NE BRO 20 N ALI 45
NW BAZ 25 WNW SEP 50 NNW FTW 20 ESE ADM 45 WNW DEQ 30 WSW HOT 55 E
LIT 15 WNW MKL 30 SSE CKV 45 NW CSV 20 SW TYS 50 NW AND 10 E AHN 40
ENE MCN 35 ENE ABY 25 NW TLH 55 WSW AAF.

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...

AN AMPLIFIED LARGE-SCALE PATTERN IS FORECAST OVER THE CONUS DURING
THE DAY ONE PERIOD. IN THE W...A REX-TYPE BLOCK WILL SLOWLY
EVOLVE...WHILE FARTHER E OVER THE PLAINS INTO MS VALLEY...
DISTURBANCES EMBEDDED WITHIN A SPLIT FLOW REGIME WILL MOVE EWD INTO
A PROGRESSIVELY MORE CONFLUENT MID-LEVEL PATTERN IN PLACE ACROSS THE
ERN THIRD OF THE NATION.

IN THE LOW-LEVELS...WEAK LOW PRESSURE INITIALLY OVER THE MIDDLE TX
COAST WILL DEVELOP NEWD ALONG INTENSIFYING FRONTAL BOUNDARY INTO
CNTRL OR NRN MS BY LATE AFTERNOON/EARLY EVENING...AND EVENTUALLY THE
CNTRL APPALACHIANS BY MONDAY MORNING.

...LOWER MS VALLEY...

SRN STREAM DISTURBANCE INITIALLY OVER THE SRN HIGH PLAINS IS
FORECAST TO WEAKEN AS IT MOVES INTO THE REGION LATER TODAY. 
HOWEVER...LOWER BRANCH OF COUPLED UPPER-LEVEL JET STREAK CIRCULATION
WILL MAINTAIN A BROAD ZONE OF WAA/ISENTROPIC ASCENT THROUGHOUT THE
PERIOD OVER THE LOWER MS AND TN VALLEYS.  THIS FORCING FOR ASCENT
WILL LIKELY MAINTAIN A LARGE PRECIPITATION SHIELD FROM N OF THE
SURFACE FRONT SWD INTO THE DEVELOPING WARM SECTOR.  DESPITE THE
INCREASING BOUNDARY-LAYER MOISTURE...THE CONSIDERABLE
CLOUDS/PRECIPITATION AND RESULTANT MOIST ADIABATIC LAPSE RATES WILL
LIMIT AIR MASS DESTABILIZATION WITH SBCAPES OF 500-800 J/KG FORECAST
BY AFTERNOON FROM ERN LA INTO MS AND AL.

IT APPEARS THAT A MORE ORGANIZED SEVERE WEATHER THREAT WILL BE
LIMITED BY THE MARGINAL INSTABILITY.  HOWEVER...SOME POTENTIAL FOR 
AN ISOLATED SEVERE STORM OR TWO WILL EXIST THIS AFTERNOON INTO
EVENING...ESPECIALLY AHEAD OF MIGRATORY...WEAK SURFACE LOW WHERE LOW
AND DEEP-LAYER SHEAR WILL BE LOCALLY ENHANCED. THE STRONGEST/MOST
ORGANIZED STORMS WILL BE CAPABLE OF AN ISOLATED WEAK TORNADO OR TWO
AND/OR MARGINAL WIND/HAIL...PRIOR TO AIR MASS SLOWLY STABILIZING
OVERNIGHT.  SHOULD IT BECOME APPARENT ENVIRONMENT WILL BECOME MORE
UNSTABLE THAN IS CURRENTLY ANTICIPATED...PORTIONS OF REGION MAY NEED
TO BE UPGRADED TO A SLIGHT RISK.

..MEAD.. 01/22/2006

...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