SPC AC 081702
DAY 3 CONVECTIVE OUTLOOK RESENT 1
NWS STORM PREDICTION CENTER NORMAN OK
1202 PM CDT SUN AUG 08 2004
VALID 101200Z - 111200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CNTRL/SRN
PLNS...
...SYNOPSIS...
WRN RIDGE/ERN TROUGH PATTERN ALREADY ESTABLISHED EXPECTED TO AMPLIFY
ON TUESDAY AS IMPULSE NOW ENTERING NRN AB DEEPENS UPON CONTINUING SE
FROM SASKATCHEWAN/MB INTO MN/WI. THIS WILL USHER A NEW SURGE OF
POLAR AIR INTO THE N CNTRL U.S...AND REINFORCE EXISTING COLD FRONT
LIKELY TO EXTEND FROM THE MID MS VLY TO THE CNTRL HI PLNS AT THE
START OF THE PERIOD. THE FRONT SHOULD ACCELERATE S ACROSS THE CNTRL
PLNS LATER TUESDAY...AND REACH A W TX TO KY AXIS BY 12Z WEDNESDAY.
...CNTRL PLNS...
WNWLY MID LEVEL FLOW DOWNSTREAM FROM WRN STATES RIDGE WILL MAINTAIN
PLUME OF STEEP MID LEVEL LAPSE RATES ACROSS CNTRL PORTIONS OF THE
PLNS ON TUESDAY. COMBINATION OF SURFACE HEATING...MODEST BOUNDARY
LAYER MOISTURE INFLOW AND CONVERGENCE ALONG COLD FRONT SHOULD
SUPPORT DEVELOPMENT OF DIURNALLY ENHANCED STORMS/STORM CLUSTERS OVER
PARTS OF SE CO/SRN KS/NRN AND WRN OK AND THE TX PANHANDLE.
POTENTIAL WILL ALSO EXIST FOR ELEVATED POST FRONTAL STORMS NWD/WWD
INTO PARTS OF NEB AND NE CO AS SHALLOW COOL AIR MASS SURGES SWD
BENEATH PERSISTENT WNWLY MID LEVEL FLOW.
GIVEN STEEP MID LEVEL LAPSE RATES AND PRESENCE OF MODERATE /25 KT/
DEEP NWLY SHEAR...THREAT WILL EXIST FOR HAIL AND LOCALLY DAMAGING
WIND WITH THE STRONGEST SURFACE-BASED STORMS/POSSIBLE SUPERCELLS IN
KS/SE CO AND OK. HAIL MAY ALSO ACCOMPANY POST FRONTAL CELLS IN
NEB/NRN KS AND NE CO. SOME OF THE SRN KS/OK/TX PANHANDLE ACTIVITY
MAY EVOLVE INTO A LARGE CLUSTER THAT MOVES SSE AHEAD OF THE FRONT
TUESDAY NIGHT/EARLY WEDNESDAY.
...ERN STATES...
UPPER IMPULSE NOW IN ND EXPECTED TO WEAKEN AND LIFT NWD INTO
ONTARIO/QUEBEC ON TUESDAY AS UPSTREAM SYSTEM AMPLIFIES SEWD INTO MN.
AS A RESULT...LARGE SCALE FORCING FOR ASCENT WILL BE WEAK ACROSS
THE UPR OH VLY/NRN APLCNS AND MID ATLANTIC REGION. MID LEVEL LAPSE
RATES WILL ALSO BE WEAK. BUT SURFACE HEATING AND LINGERING
CONVERGENCE ALONG ASSOCIATED COLD FRONT/PREFRONTAL TROUGHS MAY
NEVERTHELESS SUPPORT A FEW STRONG AFTERNOON/EVENING STORMS GIVEN
PRESENCE OF 25-30 KT DEEP WSWLY SHEAR AND MLCAPE APPROACHING 1000
J/KG.
..CORFIDI.. 08/08/2004
...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.
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED FOR 1100Z
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