[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 171959
SWODY1
SPC AC 171956

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0256 PM CDT MON MAY 17 2004

VALID 172000Z - 181200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 40 NNW
CLE 20 W SPI 30 SW CNU 30 NNW GAG GCK 45 N LAA 35 SE LIC 50 ENE LIC
40 ESE GLD 10 WNW LNK MCW EAU 15 ENE MQT.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 65 WNW HVR 45 N BIL
45 W 4BQ 35 SSE REJ 40 SSW PHP 50 SSW MHE 30 ENE FSD 30 NE MSP 30 NE
IWD ...CONT... 25 NE EFK 10 SSW BTV 30 WNW ALB 15 W ISP ...CONT...
25 NE ECG RDU CLT AHN 15 E MCN 60 SE MCN AGS 20 SSE FLO 20 NE OAJ
HSE ...CONT... 35 N MLB 25 SE AGR 55 SSW MIA ...CONT... 30 SSE CRP
ALI 15 ENE NIR CLL 40 SE MLC FYV 35 WSW UNO SGF JLN BVO PNC 40 ENE
GAG GAG CDS 45 SE LBB BGS 60 E FST 35 ESE P07 ...CONT... 65 SE ELP
40 SW ROW 45 SSE LVS RTN 15 ENE ASE 50 ESE VEL 45 NW PUC 45 N ENV 45
WNW OWY 35 SE RBL 35 NNW UKI EKA.

...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN/EVE FROM THE GREAT
LAKES REGION INTO THE CNTRL PLAINS....

...UPPER MISSISSIPPI VALLEY INTO LOWER GREAT LAKES REGION...
MID-LEVEL SPEED MAXIMUM...WHICH EMANATED FROM SOUTHERN BRANCH TROUGH
OVER THE NORTHEAST PACIFIC/NORTHWESTERN U.S...CONTINUES TO
ACCELERATE EAST NORTHEASTWARD ACROSS THE UPPER GREAT LAKES REGION. 
STRONG FORCING FOR UPWARD VERTICAL MOTION WITH THIS FEATURE IS
RAPIDLY SHIFTING ACROSS EASTERN ONTARIO/WESTERN QUEBEC...BUT
ADDITIONAL CONVECTIVE DEVELOPMENT HAS OCCURRED IN ITS WAKE ACROSS
LOWER MICHIGAN.  THIS ACTIVITY APPEARS TO HAVE BEEN SUPPORTED BY
FORCING ASSOCIATED WITH WEAKENING WAVE/CYCLONIC VORTICITY CENTER
LIFTING OUT OF THE MIDDLE MISSISSIPPI VALLEY INTO THE SOUTHERN GREAT
LAKES REGION...JUST SOUTH OF STRONGER WESTERLIES.  MEAN MIXED LAYER
CAPE AROUND 1000 J/KG IS SUPPORTING A FEW VIGOROUS UPDRAFTS. 
EVOLUTION OF SLIGHTLY MORE ORGANIZED CONVECTIVE SYSTEM APPEARS
POSSIBLE AS SURFACE COLD POOL DEVELOPS/PROPAGATES ACROSS SOUTHERN
ONTARIO/LAKE ERIE AREA LATE THIS AFTERNOON

OTHERWISE...ANOTHER LOW AMPLITUDE SHORT WAVE TROUGH IS EVIDENT IN
SATELLITE IMAGERY OVER THE DAKOTAS/WESTERN NEBRASKA.  SYSTEM IS
LIFTING NORTHEASTWARD TOWARD THE UPPER GREAT LAKES REGION...AND
MODELS SUGGEST FORCING WILL BECOME SUFFICIENT TO SUPPORT INCREASING
CONVECTIVE DEVELOPMENT ALONG/AHEAD OF SURFACE FRONT ACROSS THE UPPER
MISSISSIPPI VALLEY.  FRONT CURRENTLY TRAILS FROM ONTARIO SURFACE LOW
SOUTHWARD ACROSS NORTHWEST WISCONSIN/SOUTHEAST MINNESOTA/NORTHWEST
IOWA...WITH MOIST BOUNDARY LAYER AHEAD OF IT NOW MODERATELY UNSTABLE
WITH CAPE IN EXCESS OF 1000 J/KG.  THIS IS SUPPORTIVE OF STRONG
UPDRAFTS CAPABLE OF PRODUCING LARGE HAIL.

FORCING ASSOCIATED WITH TROUGH IS ALREADY EVIDENT IN ONGOING
CONVECTIVE DEVELOPMENT TO THE WEST OF FRONT...FROM CENTRAL NEBRASKA
INTO NORTHWEST IOWA.  AS THIS SPREADS ACROSS UNSTABLE PRE-FRONTAL
ENVIRONMENT...MODELS SUGGEST EVOLUTION OF CLUSTER OR LINE OF STORMS
IS POSSIBLE ACROSS PARTS OF EASTERN IOWA/WISCONSIN/NORTHERN ILLINOIS
BY AROUND 18/03Z.  30 TO 40 KT MEAN FLOW REGIME WILL ENHANCE
POTENTIAL FOR DAMAGING WINDS WITH ACTIVITY.  THREAT MAY PERSIST INTO
THE OVERNIGHT HOURS...SPREADING EASTWARD ACROSS LOWER MICHIGAN...
WHERE WESTERLY LOW-LEVEL JET IS PROGGED TO STRENGTHEN IN RESPONSE TO
MERGING SOUTHERN AND NORTHERN BRANCH SHORT WAVE TROUGHS.

...CENTRAL PLAINS...
POTENTIAL FOR ORGANIZED CONVECTIVE DEVELOPMENT THROUGH THE REMAINDER
OF THIS FORECAST PERIOD APPEARS BEST NORTH/NORTHEAST OF SURFACE LOW
OVER SOUTHWEST KANSAS. AHEAD OF COLD FRONT NOSING SOUTHWARD THROUGH
SOUTHERN NEBRASKA/NORTHWEST KANSAS...MEAN MIXED LAYER CAPE IS NOW ON
THE ORDER OF 1000 TO 1500 J/KG.  FURTHER DESTABILIZATION IS LIKELY
WITH ADDITIONAL HEATING...AND AREA OF FOCUSED LOW-LEVEL CONVERGENCE
MAY SUPPORT CONVECTIVE DEVELOPMENT NEAR/NORTHWEST OF DODGE CITY INTO
THE RUSSELL/ CONCORDIA AREAS BY 18/00Z.  VERTICAL SHEAR/INSTABILITY
WILL BE SUFFICIENT FOR ISOLATED SUPERCELLS.

EVOLUTION OF LARGER CLUSTER OF STORMS IS LIKELY THIS EVENING ACROSS
WESTERN/CENTRAL KANSAS.  THIS WILL BE SUPPORTED BY
DIFLUENT/DIVERGENT UPPER FLOW FIELD IN EXIT REGION OF MID/UPPER JET
NOSING INTO/ THROUGH THE FOUR CORNERS REGION...AND FORCING ON NOSE
OF INTENSIFYING SOUTHERLY LOW-LEVEL JET.  AS THIS OCCURS... PRIMARY
THREAT WILL TRANSITION FROM LARGE HAIL TO OCCASIONAL STRONG WIND
GUSTS ASSOCIATED WITH DEVELOPING SURFACE COLD POOLS.  DAMAGING WIND
POTENTIAL MAY PERSIST INTO THE OVERNIGHT HOURS... WITH ACTIVITY
GRADUALLY DEVELOPING EASTWARD ACROSS KANSAS IN RESPONSE TO VEERING
LOW-LEVEL JET.

..KERR.. 05/17/2004

...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.