[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 231221
SWODY1
SPC AC 231219

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0719 AM CDT SAT OCT 23 2004

VALID 231300Z - 241200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 10 WSW
BLV 35 ESE MLI LNR 20 NNE LSE 30 WSW RHI 40 NNW GRB 10 SSW MTW 25 E
MKE 15 SSE SBN IND 25 NW SDF BWG CBM 30 WNW HEZ 10 N SHV HOT 20 NW
ARG 10 WSW BLV.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 45 N ERI PIT 20 NE
BKW HKY 20 SSE AHN 35 N PNS 35 WSW PNS ...CONT... 25 S CRP 35 WNW
MFE ...CONT... 65 S MRF 30 S MRF 30 SSW FST 40 WNW SJT 30 ESE ABI 10
E FTW 25 W FSM 30 SSE SGF 10 ESE JEF 30 SSW BRL 20 SE CID 55 NNE ALO
35 NNW RST 30 WSW MSP 30 WSW RWF 15 ENE BKX 65 N ATY 35 WNW BJI 35
ESE RRT.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 35 NW CTB 15 W GTF 25
SW LWT 70 NNE BIL 65 ENE BIL 50 ESE BIL 40 NW JAC 30 SW SUN 60 SSW
BOI 50 NE 4LW 25 NW MFR 50 NNW 4BK.

...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN AND EVE ACROSS PARTS
OF THE MISSISSIPPI VALLEY....

RATHER SHARP MID/UPPER RIDGING IS STILL EVIDENT IN LATEST SATELLITE
IMAGERY...EXTENDING ALONG AN AXIS FROM WESTERN GULF OF MEXICO HIGH
CENTER NORTHEASTWARD TO ANOTHER DEVELOPING HIGH CENTER ACROSS THE
EASTERN CANADIAN PROVINCES.  UPSTREAM ...A SHORT WAVE TROUGH
CONTINUES TO LIFT NORTHEASTWARD ACROSS THE MISSOURI AND UPPER
MISSISSIPPI VALLEYS...AS ANOTHER TROUGH MIGRATES EASTWARD ACROSS THE
PACIFIC NORTHWEST AND NORTHERN INTERMOUNTAIN REGION.  BOTH FEATURES
WILL GENERALLY REMAIN PROGRESSIVE...AS YET ANOTHER STRONG SHORT WAVE
TROUGH DIGS SOUTH OF THE GULF OF ALASKA.

LEAD SHORT WAVE TROUGH WILL REMAIN MOST PROMINENT WITH REGARD TO
CONVECTIVE OUTLOOK THROUGH THIS FORECAST PERIOD...AND MODELS ARE
FAIRLY SIMILAR IN ITS FORECAST EVOLUTION...AS IT PROGRESSES INTO/
THROUGH DOWNSTREAM RIDGE AXIS. SYSTEM IS PROGGED TO BREAK DOWN INTO
A COUPLE SMALLER SCALE TROUGHS...WITH NORTHERN PORTION CONTINUING
SLOWLY EASTWARD INTO THE GREAT LAKES...WHILE SOUTHERN PORTION
ACCELERATES EAST SOUTHEASTWARD ACROSS THE LOWER OHIO/TENNESSEE
VALLEYS INTO THE SOUTHEAST STATES BY LATE TONIGHT.  THIS WILL LEAD
TO WEAKENING OF BOTH MID/UPPER RIDGE...AND ATLANTIC COAST STATES
SURFACE RIDGE. DESTABILIZATION...HOWEVER...APPEARS UNLIKELY TO
BECOME SUFFICIENT TO SUPPORT STRONG/SEVERE CONVECTIVE
DEVELOPMENT...EXCEPT PERHAPS IN A NARROW CORRIDOR NEAR/EAST OF THE
MISSISSIPPI RIVER.

...MISSISSIPPI VALLEY...
COLD FRONT ASSOCIATED WITH SHORT WAVE TROUGH CURRENTLY EXTENDS FROM
MINNESOTA SURFACE LOW SOUTHWARD ACROSS WESTERN IOWA AND NORTHWEST
MISSOURI...THROUGH SOUTHEAST KANSAS INTO CENTRAL OKLAHOMA AND
NORTHWEST TEXAS.  AHEAD OF FRONT...TONGUE OF 60F+ DEW POINTS IS
EVIDENT IN SURFACE ANALYSIS FROM THE WESTERN/CENTRAL GULF COAST
NORTHWARD THROUGH THE UPPER MISSISSIPPI VALLEY.  WITH COOL/DRY
ATLANTIC COAST SURFACE RIDGE SLOW TO WEAKEN...AND FRONT ADVANCING
EASTWARD INTO THE MISSISSIPPI VALLEY...MOIST TONGUE WILL GRADUALLY
NARROW THROUGH THE DAY.

HOWEVER...MID-LEVEL DRY SLOT HAS OVERSPREAD WARM SECTOR AIR
MASS...AND APPEARS TO LIKELY TO ALLOW AT LEAST NARROW CORRIDOR OF
HEATING AND SURFACE-BASED DESTABILIZATION AS FORECAST BY MODELS. 
MEAN MIXED LAYER CAPE UP TO 1000 J/KG IS POSSIBLE BY EARLY THIS
AFTERNOON FROM PARTS OF SOUTHEAST MISSOURI AND SOUTHERN ILLINOIS
INTO CENTRAL WISCONSIN.  THIS SHOULD BECOME SUPPORTIVE OF AT LEAST
SCATTERED THUNDERSTORM ACTIVITY...AS COOLING/LIFT NEAR UPPER COLD
TROUGH SPREADS INTO REGION. SHEAR PROFILES WILL REMAIN SUFFICIENT TO
SUPPORT AT LEAST BRIEF UPDRAFT ROTATION...ENHANCING RISK FOR LARGE
HAIL/DAMAGING WIND GUSTS IN MOST VIGOROUS CELLS.  FORCING NEAR FRONT
MAY ULTIMATELY CONTRIBUTE TO EVOLUTION OF NARROW SQUALL LINE...BUT
ACTIVITY SHOULD WEAKEN FAIRLY QUICKLY DURING THE EARLY EVENING HOURS
WITH LOSS OF DAYTIME HEATING.

FARTHER SOUTH...SEPARATE AREA OF STRONGER FORCING MAY SUPPORT
DEVELOPMENT OF PRE-FRONTAL CONVECTIVE LINE BY LATE AFTERNOON/EARLY
EVENING...FROM PARTS OF EASTERN ARKANSAS/NORTHERN LOUISIANA INTO
WESTERN TENNESSEE AND MISSISSIPPI.  ACTIVITY APPEARS LIKELY TO BE
BASED IN WEAK TO MODERATELY UNSTABLE BOUNDARY LAYER WITH 70F+ DEW
POINTS.  WHILE CAPE MAY BE LARGE ENOUGH TO SUPPORT VIGOROUS
UPDRAFTS...WARM/MOIST THERMODYNAMIC ENVIRONMENT WITH HIGH
FREEZING/WET-BULB ZERO LEVELS DOES NOT APPEAR TO FAVOR LARGE HAIL. 
HOWEVER...A FEW STRONG WIND GUSTS MAY ACCOMPANY LINE BEFORE IT
WEAKENS/SHIFTS INTO THE EASTERN GULF STATES LATER TONIGHT.

..KERR/JEWELL.. 10/23/2004

...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.