DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 280441
SWODY1
SPC AC 280439

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1139 PM CDT WED MAR 27 2013

VALID 281200Z - 291200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
THE LARGE-SCALE PATTERN WILL BE CHARACTERIZED BY A BROAD UPPER RIDGE
ENCOMPASSING MUCH OF THE WRN CONUS...WHILE AN UPPER TROUGH INITIALLY
OVER THE MID-ATLANTIC MOVES OFFSHORE. A SERIES OF WEAK IMPULSES WILL
EJECT NEWD FROM A PARENT OFFSHORE UPPER LOW OVER THE ERN PACIFIC AND
INTO THE PARTS OF THE PAC NW AND WRN GREAT BASIN. A MODEST NWD
RETURN OF GULF MOISTURE WILL OCCUR FROM TX NWD INTO THE LOWER-MO
VALLEY AS A LEE SFC TROUGH BECOMES ESTABLISHED OVER THE SRN HIGH
PLAINS.

...PARTS OF THE SRN PLAINS AND LOWER-MO VALLEY...
DEEP BOUNDARY LAYER MIXING OVER THE TX S PLAINS SWD TOWARDS THE
DAVIS MTNS WILL OCCUR BENEATH STEEP MIDLEVEL LAPSE RATES...YIELDING
ESTIMATED MLCAPE VALUES OF 200-500 J/KG DURING PEAK HEATING. A FEW
HIGH-BASED TSTMS COULD DEVELOP INVOF A LEE SFC TROUGH/DRYLINE WHERE
CINH IS MINIMIZED. TSTMS SHOULD QUICKLY DISSIPATE WITH THE ONSET OF
DIURNAL COOLING AS THE BOUNDARY LAYER STABILIZES.

A SEPARATE AREA OF TSTM DEVELOPMENT IS FORECAST TO OCCUR PRIMARILY
AFTER 28/00Z FROM PARTS OF OK NEWD INTO CNTRL MO WITHIN A WEAK
LOW-LEVEL WAA REGIME...AS AN UPPER IMPULSE PASSES THROUGH THE MID-MO
AND UPPER-MS VALLEYS. HOWEVER...MARGINAL INSTABILITY WILL PRECLUDE
INTRODUCTION OF SVR PROBABILITIES.

...NERN ORE AND W-CNTRL ID...
AN UPPER IMPULSE /POSITIONED APPROXIMATELY 500 W SFO AS OF 28/04Z
PER WATER VAPOR IMAGERY/ WILL TRANSLATE NEWD AND REACH NERN ORE
DURING PEAK HEATING. ALTHOUGH GRADUAL MIDLEVEL HEIGHT RISES ARE
FORECAST TO OCCUR THROUGHOUT THE DAY...SUFFICIENT DAYTIME
HEATING/DESTABILIZATION COULD SUPPORT A FEW TSTMS DURING THE
AFTERNOON/EARLY EVENING.

..ROGERS/GRAMS.. 03/28/2013

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.