[SWODY2] SWODY2

[SWODY2 at goshenarc.org]

ACUS02 KWNS 111746
SWODY2
SPC AC 111745

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1245 PM CDT WED MAY 11 2005

VALID 121200Z - 131200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 90 SW
P07 15 S HOB 25 W GCK 35 SW GLD 40 N GLD 15 SSW HSI 10 E OMA 35 S
FOD 25 NW CID 25 SSE DBQ 35 SW RFD 20 SSW MMO 20 SW BMI 40 S UIN 30
NNW TBN 25 N FYV 15 ESE TUL 40 SSE OKC 10 WNW BWD 65 W COT.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 45 W MRF 45 N ROW 15
SE LHX 20 WSW COS 35 N 4BL 55 W U24 45 SSE TWF 25 SSW MQM 30 S BIL
40 WSW PHP 45 ENE PIR 60 SSW BJI 10 NE IWD 30 S TVC 20 NE CLE HLG 15
SSW SHD 25 ENE ECG ...CONT... 20 SSE SAV 20 WSW ATL 35 S LUL 50 W
MLU 25 ESE FSM 30 N DUA 10 SE TPL 25 ESE MFE.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE
CENTRAL/SRN PLAINS TO THE UPPER MIDWEST...

...SYNOPSIS...
LARGE UPPER LOW OVER THE WRN STATES WILL DE-AMPLIFY FROM DAY 1 INTO
DAY 2 AS IT TRACKS NEWD TOWARD THE NRN PLAINS ON THURSDAY.  THIS LOW
WILL EVOLVE INTO AN OPEN WAVE ACROSS THE DAKOTAS THURSDAY NIGHT AS
IT BEGINS TO MERGE WITH NRN STREAM FLOW OVER CANADA.  A COUPLE OF
SHORT WAVE TROUGHS ASSOCIATED WITH THE UPPER LOW ARE PROGGED TO MOVE
ENEWD ACROSS THE CENTRAL PLAINS TO UPPER MIDWEST BEGINNING LATE
THURSDAY AFTERNOON...WITH STRONGEST HEIGHT FALLS EXPECTED GENERALLY
AFTER 00Z.

AT THE SURFACE...A LOW INITIALLY OVER SRN NEB WILL WEAKEN AS IT
TRACKS EWD TOWARD SRN IA BY 13/00Z...WITH A TRAILING COLD FRONT
MOVING SLOWLY EWD ACROSS CENTRAL KS.  DRY LINE EXTENDING SWD ACROSS
THE OK/TX PANHANDLES TO WRN TX WILL REMAIN QUASI-STATIONARY THIS
PERIOD.  MEANWHILE...A BOUNDARY EXTENDING ESEWD TO THE OH VALLEY
FROM THE NEB SURFACE LOW SHOULD REMAIN MAINLY STATIONARY...BUT
RETREAT NWD OVER MID MS AND LOWER OH VALLEYS.

...CENTRAL/SRN PLAINS EWD INTO THE UPPER MIDWEST...
ELEVATED MCS...POTENTIALLY SEVERE...SHOULD BE ONGOING AT THE START
OF THE PERIOD ACROSS PORTIONS OF CENTRAL/ERN NEB AND NRN KS ALONG
NOSE OF SWLY LLJ.  THIS ACTIVITY IS EXPECTED TO DIMINISH IN
INTENSITY AS THE LLJ WEAKENS/REDEVELOPS FROM THE SRN PLAINS TO LOWER
MO RIVER VALLEY BY AFTERNOON.  AXIS OF RICH MOISTURE WILL REMAIN
ACROSS THE WARM SECTOR WITH SURFACE DEWPOINTS IN THE UPPER 60S
CONTRIBUTING TO STRONG INSTABILITY.  SURFACE HEATING IS EXPECTED TO
BE THE PRIMARY IMPETUS FOR THUNDERSTORM DEVELOPMENT ALONG THE DRY
LINE AND NEWD ALONG THE COLD FRONT TO THE SURFACE LOW...GIVEN THE
LACK OF A WELL DEFINED MID LEVEL SYSTEM MOVING OVER THIS REGION
DURING THE AFTERNOON.

LARGE SCALE ASCENT WITHIN THE ENTRANCE REGION OF A 50-60 KT SSWLY
MID LEVEL JET...TRANSLATING NEWD ACROSS THE CENTRAL PLAINS TO NRN MS
VALLEY...WILL AID IN SUSTAINED UPDRAFTS AS STORMS BECOME RAPIDLY
SEVERE ALONG THE DRY LINE FROM NWRN TX INTO WRN OK AND SWRN-SOUTH
CENTRAL KS WITHIN A VERY UNSTABLE AIR MASS.  DEEP LAYER SHEAR
VECTORS CROSSING THE DRY LINE WILL SUPPORT SUPERCELLS WITH VERY
LARGE HAIL...DAMAGING WINDS AND TORNADOES POSSIBLE.  STORMS WILL
ALSO DEVELOP NEWD ALONG THE COLD FRONT TO THE VICINITY OF THE
SURFACE LOW AS IT TRACKS INTO SRN IA.  MODERATE INSTABILITY AND DEEP
LAYER SHEAR VECTORS ORIENTED ALONG THE BOUNDARY WOULD FAVOR A
GREATER POTENTIAL FOR LINE SEGMENTS OVER THIS AREA.

AS HEIGHT FALLS SPREAD EWD ACROSS THE CENTRAL PLAINS TO UPPER
MIDWEST...SWLY LLJ WILL STRENGTHEN TO 40-45 KT NOSING INTO NRN
OK/SRN KS.  THIS SUGGESTS UPSCALE DEVELOPMENT INTO AN MCS WITH HAIL
AND DAMAGING WINDS BEING THE PRIMARY THREATS AS ACTIVITY SPREADS EWD
TOWARD WRN MO BY 12Z FRIDAY.

...MID MS/OH VALLEYS...
MODELS SUGGEST CONVECTION WILL DEVELOP ALONG THE SURFACE BOUNDARY
FROM SRN WV/SWRN VA WNWWD ACROSS KY TO SRN IL/SERN IA. ALTHOUGH THE
AIR MASS WILL BE MODERATELY UNSTABLE...MODEST DEEP LAYER SHEAR
SHOULD SUPPORT MULTICELLS.  PINPOINTING A HIGHER RISK FOR SEVERE
POTENTIAL IS DIFFICULT ATTM GIVEN SOME UNCERTAINTY WITH LOCATION OF
SURFACE BOUNDARY.  THUS HAVE MAINTAINED FORECAST OF LOW
PROBABILITIES.

..PETERS.. 05/11/2005

...NOTICE...
THE STATION RELATIVE POINTS IN THIS PRODUCT ARE NOW AVAILABLE
SEPARATELY UNDER THE WMO HEADINGS WUUS01 PTSDY1...
WUUS02 PTSDY2...WUUS03 PTSDY3.  THE INCLUSION OF POINTS
IN THIS DISCUSSION WILL BE DISCONTINUED AFTER THE 2005
CONVECTIVE SEASON.  A PUBLIC NOTIFICATION STATEMENT (PNS)
WILL PROVIDE DETAILS ON THE TRANSITION.