DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 071953
SWODY1
SPC AC 071951

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0151 PM CST THU FEB 07 2013

VALID 072000Z - 081200Z

...NO SVR TSTM AREAS FORECAST...

...ERN FL PANHANDLE...FAR SRN GA...
A WEAK SURFACE LOW WILL CONTINUE TO MOVE ENEWD ACROSS THE FL
PANHANDLE AND INTO SRN GA ALONG A QUASI-STATIONARY BOUNDARY. S OF
THIS FRONT...THE AIR MASS WAS MARGINALLY UNSTABLE...WITH BETTER
MOISTURE CONFINED OVER THE WATER OR ALONG THE IMMEDIATE COAST. A
BROKEN LINE OF RAIN AND STORMS MAY CONTINUE TO POSE A MARGINAL
SEVERE THREAT IN THE FORM OF BRIEF WATERSPOUTS OR TORNADOES...BUT
SHOULD DIMINISH THIS EVENING AS THE STRONG FORCING CONTINUES TO LIFT
NEWD AWAY FROM THE INSTABILITY.

...ARKLATEX...
A COLD FRONT EXTENDS FROM NWRN TX INTO SERN OK AS OF 20Z WITH AREAS
OF HEATING COINCIDENT WITH DEWPOINTS IN THE 50S F CREATING WEAK
INSTABILITY. THE FRONT WILL CONTINUE TO DRIFT SWD ACROSS THE REGION
THIS EVENING AND OVERNIGHT...OVERTAKING THE DRYLINE E OF THE I-35
CORRIDOR AFTER 03Z. IT APPEARS THAT THE PRIMARY FORCING ASSOCIATED
WITH THIS FRONT WILL BE MAINLY N OF THE PREVIOUS HAIL PROBABILITIES
WHERE THE INFLUENCE OF THE UPPER SHORTWAVE TROUGH WILL BE
GREATER...FROM NRN AR TO THE OH VALLEY. WHILE CONDITIONAL HAIL
PROBABILITIES ARE GREATER ACROSS NERN TX...IT APPEARS THAT DRY AIR
ALOFT...TIME OF DAY...AND LACK OF APPRECIABLE FORCING MAY LIMIT
SEVERE POTENTIAL.

ONE CAVEAT IS IF A STORM CAN GET GOING BEFORE SUNSET ACROSS SERN
OK/NERN TX. CURRENT SURFACE OBS SHOW A NARROW LOW LEVEL LAPSE RATE
PLUME ALONG AN ACT-DFW LINE...AND VISIBLE IMAGERY DOES SHOW A CU
FIELD DEVELOPING. HOWEVER...ANY STORMS THAT MAY FORM IN THIS
SCENARIO ARE EXPECTED TO BE QUITE ISOLATED...WITH ONLY A NARROW TIME
WINDOW OF MARGINAL HAIL THREAT. THEREFORE...HAVE REMOVED SEVERE HAIL
PROBABILITIES FOR TONIGHT.

..JEWELL.. 02/07/2013

.PREV DISCUSSION... /ISSUED 1015 AM CST THU FEB 07 2013/

MORNING WATER VAPOR LOOPS SHOW TWO SHORTWAVE TROUGHS AFFECTING THE
SOUTHERN UNITED STATES. BOTH OF THESE FEATURES WILL PROVIDE SOME
RISK FOR THUNDERSTORM ACTIVITY THIS AFTERNOON AND TONIGHT.

...AL/FL/GA...
ONE SHORTWAVE TROUGH IS CURRENTLY OVER SOUTHERN MS/AL AND THE FL
PANHANDLE. A BROKEN LINE OF THUNDERSTORMS IS ASSOCIATED WITH THIS
SYSTEM...EXTENDING FROM SOUTHEAST AL INTO THE CENTRAL GULF OF
MEXICO. SURFACE OBSERVATIONS SHOW DEWPOINTS ONLY IN THE 50S AND
LOWER 60S INLAND...WITH TRAJECTORIES SUGGESTING THAT SIGNIFICANT
FURTHER MOISTENING IS UNLIKELY. FORECAST SOUNDINGS USING THESE
SURFACE CONDITIONS INDICATE THAT STORMS ARE LIKELY ELEVATED
EVERYWHERE BUT ALONG THE IMMEDIATE COAST. THE CONVECTION SHOULD
CONTINUE THROUGH THE DAY AND SPREAD EASTWARD INTO SOUTHERN GA AND
NORTH FL. THE STRONGEST CELLS MAY BE CAPABLE OF GUSTY WINDS OR EVEN
A BRIEF TORNADO. HOWEVER...PRESENT INDICATIONS ARE THAT POOR
THERMODYNAMIC PARAMETERS WILL PRECLUDE A MORE ORGANIZED SEVERE
EVENT.

...ARKLATEX...
A SECOND SHORTWAVE TROUGH IS NOTED OVER NORTHEAST NM AND THE TX
PANHANDLE. THIS FEATURE WILL TRACK EASTWARD AND INTO OK BY THIS
EVENING. MEANWHILE...A SURFACE COLD FRONT IS SAGGING SOUTHWARD
ACROSS OK. MODELS ARE IN GENERAL AGREEMENT THAT SCATTERED SHOWERS
AND THUNDERSTORMS WILL DEVELOP ALONG THE FRONT THIS AFTERNOON AND
TONIGHT AS THE UPPER SYSTEM ARRIVES. LOW LEVEL WINDS ARE FORECAST
TO BE WEAK...AND CAPE VALUES WILL BE QUITE LOW. NEVERTHELESS...
COOL TEMPERATURES ALOFT AND STEEP MID LEVEL LAPSE RATES MAY BE
SUFFICIENT FOR A RISK OF HAIL IN THE STRONGEST STORMS.

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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.