[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 101621
SWODY1
SPC AC 101617

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1117 AM CDT FRI SEP 10 2004

VALID 101630Z - 111200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 70 ENE
ELO HIB 40 NW BRD 45 ENE FAR 20 ESE GFK 45 W RRT.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 15 W CZZ 40 NNE SAN
15 SW RAL 25 N LAX 15 NW PMD 30 ESE EDW 15 NE DAG 50 NE DAG 65 WSW
LAS 65 SSW DRA 45 ENE NID 50 WSW DRA 65 NNE DRA 40 S ELY 15 ENE U24
40 SE EVW 35 ESE RIW 40 ENE WRL 65 ENE BIL 40 N MLS ISN 55 NNW MOT
...CONT... 50 W ANJ 35 NNE MSN 50 ENE ALO OFK 30 SE LBF 50 SSW LAA
55 WSW RTN 70 SE PGA 65 NNW GBN 70 SSW GBN.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 55 WSW COT 15 NNE HDO
10 NNE CLL 30 NW HOU 35 NE HOU 25 WNW LCH 25 SSE POE 35 N BTR 20 SSE
LUL 40 SSW AHN 45 NW FLO 40 N HSE.

...THERE IS A SLGT RISK OF SVR TSTMS OVER NRN MN...

...NRN PLAINS/UPPER MS VALLEY...
SATELLITE IMAGERY SHOWS WELL-DEFINED SHORT WAVE TROUGH MOVING EWD
ACROSS MT AS PROGRESSIVE FLOW PATTERN CONTINUES OVER THE NRN STATES.
MODELS INDICATE THIS TROUGH WILL AMPLIFY AS IT MOVES ACROSS THE NRN
PLAINS IN RESPONSE TO Q-G THERMAL ADVECTION PROCESSES. A SURFACE
COLD FRONT CURRENTLY EXTENDING FROM EXTREME NWRN MN SWWD ACROSS
CENTRAL SD THEN WWD INTO WY WILL MOVE EWD THIS AFTERNOON...REACHING
N CENTRAL MN/ERN SD BY THIS EVENING AND WRN LAKE SUPERIOR/SWRN
MN/NRN NEB BY 11/12Z.

12Z SOUNDINGS SHOW A PLUME OF STEEP MID LEVEL LAPSE RATES FROM THE
NRN/CENTRAL ROCKIES EWD ACROSS THE NRN PLAINS AND UPPER MS VALLEY. 
THIS IS ASSOCIATED WITH A WARM LAYER BASED NEAR 850 MB THAT IS
EFFECTIVELY CAPPING SURFACE PARCELS FROM REACHING THE LFC. HOWEVER
SEVERAL AREAS OF ELEVATED CONVECTION /SWRN MN..NRN ND...AND NRN CO
INTO WRN NEB/ ARE SPREADING EWD AND NEWD IN ADVANCE OF WEAKER SHORT
WAVE TROUGHS MIGRATING ALONG THE SRN EDGE OF THE WESTERLIES. LOW
LEVEL MOISTURE IN THE WARM SECTOR IS EXPECTED TO BE LIMITED EXCEPT
OVER PARTS OF MN WHERE SURFACE DEW POINTS IN THE 55-60F RANGE WILL
BE COMMON.  VISIBLE SATELLITE IMAGERY SUGGESTS STRONGER DIURNAL
HEATING WILL OCCUR FROM SD INTO NRN MN WHERE CLEAR SKIES ARE
LOCATED...CONTRIBUTING TO UNSTABLE ENVIRONMENT NEAR THE FRONT WITH
MLCAPE OF 1000-1500 J/KG THIS AFTERNOON AND EVENING.

THE CAP IS LIKELY TO INHIBIT DEVELOPMENT OF SURFACE-BASED CONVECTION
THROUGH MUCH OF THE AFTERNOON...ALTHOUGH COMBINATION OF LOW LEVEL
HEATING AND LARGE SCALE ASCENT IN ADVANCE OF THE MT SHORT WAVE
TROUGH WILL GRADUALLY WEAKEN THE CAP.  NONETHELESS... MODEL GUIDANCE
FROM THE 12Z RUC/ETA/GFS AND 09Z SREF INDICATE THAT COVERAGE OF DEEP
CONVECTION IN THE WARM SECTOR WILL BE LIMITED...WITH THE HIGHER
THUNDERSTORM PROBABILITIES CONFINED TO PARTS OF NRN MN.  ADDITIONAL
CONVECTION MAY DEVELOP BEHIND THE FRONT WHERE DYNAMIC FORCING
ASSOCIATED WITH THE TROUGH WILL BE OCCURRING.  ALTHOUGH COVERAGE OF
DEEP CONVECTION MAY BE SOMEWHAT LIMITED...THE PRESENCE OF 40-50 KT
WSWLY MID LEVEL WINDS AND RESULTANT STRONG VERTICAL SHEAR OF 35-45
KT IN THE LOWEST 6 KM WILL ENHANCE STORM ORGANIZATION OF CELLS THAT
CAN DEVELOP.  THUS...THERE WILL BE POTENTIAL FOR A FEW STRONG/SEVERE
STORMS TO DEVELOP LATER THIS AFTERNOON AND EVENING WITH THREAT FOR
HAIL AND STRONG WIND GUSTS.

..WEISS/JEWELL.. 09/10/2004

...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.