[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 220537
SWODY1
SPC AC 220535

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1235 AM CDT THU SEP 22 2005

VALID 221200Z - 231200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 25 W
CLE 25 NE DAY 10 NNE SLO 50 NNE SGF 45 SSW EMP 20 SSW SLN 25 NE CNK
30 SW DBQ 45 NE MKE 40 ESE OSC.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 SSE YUM 65 E BLH
45 NE IGM 15 NE PGA 15 NNW CNY 40 WSW CAG 30 ENE CAG 25 N LAR 45 W
BFF 40 SW MHN 25 SE BUB 15 S MCW 40 NNE GRB 20 WSW ANJ ...CONT... 30
NNW BML PSM 25 S BDL 25 WNW EWR HGR 30 NNE CHO 10 SE RIC 20 NE ECG
...CONT... 15 NNE GLS 20 SW ESF 35 W JAN 40 WNW CBM 25 N MSL 20 WNW
BNA 30 NNW HOP 25 NNE UNO UMN 20 W BVO 60 N CDS 40 SE ROW 35 SSE
ELP.

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL GRTLKS TO THE
CNTRL PLAINS...

...SYNOPSIS...
THE STRONGER WLYS ALONG THE NRN TIER OF THE COUNTRY ARE EXPECTED TO
EXPAND SWD ON THU AS A SERIES OF SRN STREAM DISTURBANCES PHASE INTO
THE NRN STREAM ACROSS THE PLAINS TO THE GRTLKS REGION. THE
STRONGEST DISTURBANCE...NOW OVER THE CNTRL PLAINS...WILL MOVE ACROSS
THE UPPER MIDWEST AND CNTRL GRTLKS THU AFTN/EVE.  ANOTHER SHORTWAVE
TROUGH WILL EJECT FROM THE FOUR-CORNERS REGION TOWARD THE CNTRL HIGH
PLAINS LATE THU.

AT THE SURFACE...PRIMARY SURFACE LOW WILL TRAVEL FROM NRN LWR MI
EARLY IN THE PERIOD INTO NRN ONTARIO BY THU NIGHT...IN TANDEM WITH
THE STRONGER UPPER LEVEL IMPULSE.  THE TRAILING COLD FRONT WILL MOVE
EWD FROM THE CNTRL GRTLKS TO WRN NEW ENGLAND BY EARLY FRI.  BUT...
TRAILING PORTION OF THE FRONT WILL SETTLE SLOWLY SWD ACROSS THE
PLAINS/MIDWEST AS IT BECOMES INCREASINGLY ALIGNED WITH WSWLY DEEP
LAYER FLOW.  THIS FRONT WILL BE THE FOCUS FOR TSTMS THU AND THU
NIGHT. 

...CNTRL/LWR GRTLKS TO THE CNTRL PLAINS...
MODEST LOW/MID-LEVEL THETA-E ADVECTION OCCURRING DOWNSTREAM FROM THE
CNTRL PLAINS IMPULSE WILL LIKELY BE SUPPORTING WIDESPREAD TSTMS FROM
NRN LWR MI WWD TO THE UPPER MS VLY EARLY THU.  STRONGEST LARGE SCALE
SUPPORT IS EXPECTED TO MOVE NEWD INTO ONTARIO DURING THE AFTN. 
THUS...TSTMS SHOULD CONTINUE SPREADING EWD FROM THE CNTRL TO THE LWR
GRTLKS THROUGH THE DAY.  SURFACE HEATING ACROSS THESE REGIONS WILL
PROBABLY BE INHIBITED BY CLOUD COVER AND PCPN. AS A RESULT...MOST
OF THE STORMS WILL REMAIN ELEVATED WITH ONLY AN ISOLD HAIL THREAT
ACROSS MOST OF LWR MI.

AHEAD OF THE FRONT...WSWLY LOW/MID-LEVEL FLOW AND STRONGER HEATING
WILL MAINTAIN AN INSTABILITY AXIS FROM MO EWD TO IL...IND AND NRN
OH.  BUT...THE WARM LAYER BETWEEN H85-H7 OBSERVED IN EVENING
SOUNDINGS WILL REMAIN STRONG.  THE CAP WILL BE WEAKEST ACROSS
NRN/CNTRL IL EWD INTO NRN OH WHERE THERE WILL BE AN ADDITIONAL LARGE
SCALE CONTRIBUTION FROM THE SHORTWAVE TROUGH.  HERE... SURFACE BASED
INITIATION COULD OCCUR BY MID-AFTN.  THE MAJORITY OF THE STRONGER
EFFECTIVE SHEAR WILL BE ON THE COLD SIDE OF THE FRONT. AS
SUCH...WHILE A SUPERCELL OR TWO CANNOT BE RULED OUT...MAIN MODE WILL
BE MULTICELL CLUSTERS WITH PERHAPS LARGE HAIL OR DAMAGING WINDS.

FARTHER WEST...CONVECTIVE EVOLUTION IS MORE PROBLEMATIC.  THE EML
WILL BE STRONGER THAN FARTHER EAST.  ADDITIONALLY...THE MASS
CONVERGENCE ALONG THE FRONT WILL WEAKEN TEMPORARILY DURING THE PEAK
HEATING HOURS...BEFORE THE NEXT UPSTREAM UPPER TROUGH EJECTS TOWARD
THE CNTRL PLAINS DURING THE EVENING.  IT IS POSSIBLE THAT SURFACE
BASED STORMS COULD INITIATE BY LATE AFTN ACROSS NRN KS/NRN MO OWING
TO STRONG HEATING.  VERTICAL SHEAR WILL BE SUFFICIENT FOR SUPERCELLS
CONTAINING LARGE HAIL/HIGH WINDS.  BUT...THE MORE LIKELY SCENARIO
WILL BE FOR ELEVATED TSTMS TO DEVELOP NEAR/N OF THE COLD FRONT
MID-EVENING ONWARD ACROSS CNTRL/NRN KS AND NRN MO AS THE MAIN
FORCING FOR LARGE SCALE ASCENT SPREADS EWD.  THESE STORMS COULD
YIELD LARGE HAIL.
  
...FOUR-CORNERS REGION...
DIURNAL TSTMS WILL BE AUGMENTED BY SRN PERIPHERY OF THE EJECTING
SHORTWAVE TROUGH.  PRESENCE OF 30-40 KTS OF MID-LEVEL FLOW AND
RELATIVELY COOL TEMPERATURES ALOFT MAY BE SUFFICIENT FOR ISOLD TSTMS
TO PRODUCE LARGE HAIL.

..RACY/JEWELL.. 09/22/2005

...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.