[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 131258
SWODY1
SPC AC 131255

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0755 AM CDT THU MAY 13 2004

VALID 131300Z - 141200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 20 WSW
BVE 30 E HEZ 60 N HOT 10 WNW UNO 25 S STL DEC 30 SE MLI 30 NW BRL 15
WNW COU 25 SE PNC 25 ENE LTS 35 SSW CDS 40 ENE BGS 55 NNE P07 55 W
JCT 15 NNW SAT 30 SSW PSX.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 S P07 25 WNW BGS
45 SSW LBB 50 NNE HOB 20 W ROW 15 N 4CR 60 SW ALS 35 E CNY 30 S SLC
65 NNE BOI 25 SSE GEG 45 NE 63S 40 ENE CTB 20 WNW GCC 35 NE DGW 45 E
CYS 40 WSW IML 50 W EAR 40 ENE BUB 20 SSW FSD 40 SW STC 40 SW DLH 25
NNW ELO ...CONT... 10 ESE SSI 15 SSW CTY.

...THERE IS A SLGT RISK OF SVR TSTMS FROM W CENTRAL IL SWD / SWWD
INTO OK / TX AND THE LOWER MS VALLEY REGION...

...SYNOPSIS...
WHILE UPPER HIGH PERSISTS ACROSS THE ERN THIRD OF THE CONUS...LARGE
UPPER TROUGH OVER THE ROCKIES ATTM WILL CONTINUE MOVING EWD INTO THE
PLAINS THROUGH THE END OF THE PERIOD.  SEVERAL SMALLER SCALE
FEATURES ARE FORECAST TO EJECT EWD / NEWD IN MODERATE CYCLONIC FLOW
AROUND SRN AND ERN PERIPHERY OF MAIN TROUGH.

AT THE SURFACE...COLD FRONT NOW EXTENDS FROM UPPER MI / WI SWWD
ACROSS THE UPPER MS / LOWER MO VALLEYS INTO WRN OK / NWRN TX.  THIS
BOUNDARY IS FORECAST TO CONTINUE MOVING EWD / SEWD WITH TIME...AND
BY THE END OF THE PERIOD SHOULD EXTEND FROM LOWER MI SWWD INTO THE
HILL COUNTRY REGION OF CENTRAL / S TX. THIS FRONT AND A DRYLINE
WHICH SHOULD SET UP ACROSS W CENTRAL TX SHOULD BE A FOCUS FOR
CONVECTIVE DEVELOPMENT THROUGH THE PERIOD...WHILE CLUSTERS OF STORMS
 ARE ALSO FORECAST TO PERSIST / MOVE SLOWLY EWD IN WARM ADVECTION
REGION ACROSS ERN TX INTO THE LOWER MS VALLEY.

...SWRN MO SWWD INTO W CENTRAL TX...
COLD FRONT CONTINUES MOVING SWD ACROSS THE TX PANHANDLE / TX SOUTH
PLAINS ATTM...WHILE OUTFLOW-ENHANCED PORTION OF BOUNDARY ACROSS NRN
OK IS MOVING MORE SLOWLY SWD.  AS STORMS NOW OVER CENTRAL OK MOVE
EWD...DAYTIME HEATING SHOULD COMMENCE ACROSS CENTRAL AND SWRN OK
INTO ADJACENT NWRN TX INTO THE TRANSPECOS REGION.  WITH MORNING FTW
/ OUN RAOBS SHOWING A LOW-LEVEL CAPPING INVERSION...EXPECT
CONVECTIVE INITIATION ALONG FRONT FROM CENTRAL OK SWWD TO BE
INHIBITED THROUGH EARLY AFTERNOON...WHILE AIRMASS BECOMES MODERATELY
TO STRONGLY UNSTABLE.  

BY EARLY TO MID AFTERNOON...EXPECT A HEATING-INDUCED LOW TO DEVELOP
OVER NWRN TX...WITH A DRYLINE EXTENDING SSWWD FROM THE LOW INTO THE
TRANSPECOS REGION.  AS THIS OCCURS...STORMS ARE EXPECTED TO DEVELOP
ACROSS SWRN OK AND NWRN TX IN INCREASING LOW-LEVEL CONVERGENCE INVOF
LOW / COLD FRONT / DRYLINE.

DESPITE ONLY 20 TO 30 KT MID-LEVEL FLOW FORECAST OVER THE WARM
SECTOR THIS AFTERNOON...MODERATE / VEERING FLOW WITH HEIGHT COMBINED
WITH DEGREE OF INSTABILITY SHOULD RESULT IN ORGANIZED / SUPERCELL
STORMS.  VERY LARGE HAIL AND LOCALLY DAMAGING WINDS ARE
EXPECTED...AND A COUPLE OF TORNADOES MAY ALSO OCCUR -- PARTICULARLY
ACROSS A SMALL PORTION OF WRN N TX / SWRN OK INVOF SURFACE LOW AND
ASSOCIATED DRYLINE / COLD FRONT INTERSECTION.  THE TORNADO THREAT
WILL LIKELY BE RELATIVELY SHORT-LIVED HOWEVER...AS CONVECTION SHOULD
INCREASE IN COVERAGE AND EVOLVE INTO ONE OR MORE MCSS WITH TIME
ACROSS OK / NRN AND CENTRAL TX.  DESPITE A POTENTIALLY SHORT-LIVED
TORNADO THREAT...THREAT FOR LARGE HAIL AND DAMAGING WINDS SHOULD
CONTINUE WELL INTO THE EVENING / OVERNIGHT AREA AHEAD OF SLOW-MOVING
FRONT.

...PORTIONS OF IL / MO...
ALTHOUGH INSTABILITY IS FORECAST TO BE MUCH MORE LIMITED AHEAD OF
COLD FRONT ACROSS THIS REGION...SUFFICIENT INSTABILITY SHOULD EXIST
FOR A CONTINUATION OF SCATTERED STORMS THROUGH MUCH OF THE PERIOD. 
ALTHOUGH DEEP-LAYER WIND FIELD IS EXPECTED TO REMAIN FAIRLY WEAK
OVER THIS REGION...SUFFICIENT SHEAR / INSTABILITY SHOULD EXIST FOR
AT LEAST A LOW-PROBABILITY SEVERE THREAT -- PARTICULARLY THIS
AFTERNOON ACROSS W CENTRAL IL AND CENTRAL MO WHEN INSTABILITY SHOULD
BE AT ITS MAXIMUM.

...ERN TX EWD INTO THE LOWER MS VALLEY...
HAVE ADDED A LARGE AREA OF SLIGHT RISK FROM ERN / SERN TX EWD ACROSS
LA...AHEAD OF SHORT-WAVE TROUGH MOVING ACROSS CENTRAL TX ATTM IN
ADVANCE OF MAIN UPPER SYSTEM.

STORMS HAVE DEVELOPED ACROSS ERN / SERN TX THIS MORNING...APPARENTLY
WITHIN ZONE OF WARM ADVECTION ON THE COOL SIDE OF REMNANT OUTFLOW
LEFT OVER FROM EARLIER LOWER MS VALLEY CONVECTIVE CLUSTER.  WITH
DEWPOINTS IN THE LOWER TO MID 70S ACROSS THIS REGION...VERY MOIST
LOW-LEVEL AIRMASS IS CONTRIBUTING TO MODERATE INSTABILITY.  WITH
MODEL FORECASTS AND LATEST VAD / VWP DATA INDICATING MODERATE
DEEP-LAYER WIND FIELD WHICH VEERS WITH HEIGHT... A THREAT FOR HAIL /
LOCALLY DAMAGING WINDS WILL BE POSSIBLE WITH A FEW OF THE STRONGER
STORMS.  ADDITIONALLY...AN ISOLATED TORNADO OR TO WILL ALSO BE
POSSIBLE GIVEN MOIST BOUNDARY LAYER / LOW LCLS AND FAIRLY STRONG
LOW-LEVEL SHEAR.  STORMS SHOULD DEVELOP / SPREAD SLOWLY EWD THIS
AFTERNOON AS UPPER TROUGH CROSSES TX...WITH A LOW-PROBABILITY SEVERE
THREAT EXTENDING AS FAR EWD AS SERN MS.

..GOSS/TAYLOR.. 05/13/2004

...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.