Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS01 KWNS 011952
SWODY1
SPC AC 011950

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0150 PM CST SUN MAR 01 2015

VALID 012000Z - 021200Z

...NO SVR TSTM AREAS FORECAST...

...SUMMARY...
WIDELY SCATTERED THUNDERSTORMS WILL OCCUR MAINLY TODAY OVER PARTS OF
CENTRAL AND SOUTHERN CALIFORNIA...OVER SOUTHEAST TEXAS AND THE LOWER
MISSISSIPPI VALLEY...AND OVER CENTRAL FLORIDA.

NO CHANGES ARE MADE TO THE OUTLOOK FOR THIS ISSUANCE.

..BROYLES.. 03/01/2015

.PREV DISCUSSION... /ISSUED 1029 AM CST SUN MAR 01 2015/

...SYNOPTIC SETUP...
SPLIT FLOW WILL PERSIST ACROSS THE LWR 48...DOWNSTREAM FROM
AMPLIFIED E PACIFIC RIDGE. ELONGATED CA/FAR E PACIFIC LOW EXPECTED
TO EDGE ONLY SLOWLY SSE UNTIL LATE IN THE PERIOD...WHEN SYSTEM
SHOULD TURN AND ACCELERATE NE IN RESPONSE TO SHORTWAVE IMPULSE NOW
OVER THE BC CST. E OF THE CA SYSTEM...ZONAL FLOW WILL PREVAIL FROM
THE PLNS TO THE E CST. HEIGHTS SHOULD REBOUND OVER THE SRN PLNS
LATER IN THE PERIOD AS NRN STREAM DISTURBANCE NOW OVER THE NRN PLNS
CONTINUES E TO THE LWR GRT LKS.

WITH THE EXCEPTION OF CNTRL/SRN FL AND FAR SE TX/PARTS OF
LA...SHALLOW ARCTIC OR MODIFIED POLAR AIR WILL LINGER OVER MOST
AREAS E OF THE RCKYS. SLIGHTLY ELEVATED WAA/MOISTURE TRANSPORT
REGIME WILL PERSIST OVER E TX AND THE LWR MS VLY...BUT WILL BE
INCREASINGLY UNDERCUT WITH TIME BY SEWD PROGRESSION OF SHALLOW
COOL-AIR SURGE NOW EVOLVING OVER THE SRN PLNS. SIMILARLY IN CNTRL
FL...OVERALL THERMAL ADVECTION WILL BE MINIMAL. WHILE DAYTIME MIXING
MAY PERMIT A SLIGHT NWD DRIFT TO OLD W-E FRONT STALLED OVER THE
CNTRL PART OF THE STATE...OVERALL CONDITIONS SHOULD REMAIN LARGELY
UNCHANGED.

...CNTRL FL TODAY...
MODERATE DAYTIME HEATING OF MARITIME TROPICAL AIR WITH MOIST
ADIABATIC TEMPERATURE PROFILES MAY YIELD SCTD AFTN SHOWERS/TSTMS
OVER PARTS OF CNTRL AND PERHAPS SRN FL. WEAK CIN AND ABSENCE OF
SIGNIFICANT THERMAL ADVECTION ACROSS REGION SUGGEST THAT ACTIVITY
WILL REQUIRE SOME DEGREE OF CONVERGENCE TO BE REALIZED...WITH THE
LATTER LIKELY BEING MAXIMIZED NEAR INTERSECTION OF OLD W-E FRONT AND
SEA-BREEZE BOUNDARIES OVER THE W CNTRL PART OF THE STATE. WHILE PW
WILL REMAIN FAIRLY HIGH...WEAK SHEAR WILL LIMIT POTENTIAL FOR ANY
SUSTAINED WIND THREAT.

...CNTRL/SRN CA TODAY/TNGT...
THE AREA OF COLDEST AIR ALOFT/STRONGEST FORCING FOR ASCENT WITH UPR
LOW/TROUGH WILL REMAIN OFF THE SRN CA CST TODAY AS UPR LOW PIVOTS
SLOWLY SSE ACROSS REGION. BUT MODERATE TO STRONG SFC HEATING BENEATH
ASSOCIATED TROUGH AXIS...AND TERRAIN CIRCULATIONS...SHOULD SUPPORT
WDLY SCTD AFTN SHOWERS/STORMS OVER PARTS OF CNTRL/SRN CA. ALTHOUGH
SMALL HAIL COULD ACCOMPANY SOME CELLS...BUOYANCY WILL BE WEAK
/AROUND 250 J/KG MUCAPE/ AND DEEP SHEAR MODEST GIVEN PROXIMITY OF
TROUGH. THUS...SUSTAINED SVR WEATHER IS NOT EXPECTED.

...E TX/LWR MS VLY THROUGH EARLY MON...
OTHER THAN A SLIGHT WEAKENING AND AFOREMENTIONED UNDERCUTTING...
LITTLE OVERALL CHANGE IS EXPECTED IN ELEVATED WAA/MOISTURE TRANSPORT
REGIME NOW IN PROGRESS OVER E TX AND THE LWR MS VLY. COUPLED WITH
ABSENCE OF MID- AND UPR-LVL FORCING FOR ASCENT...THE PROSPECTS FOR
STRONG TO SVR CONVECTION APPEAR MINIMAL. NEVERTHELESS...SPORADIC
CLUSTERS OF SLIGHTLY ELEVATED TSTMS LIKELY WILL PERSIST AND SPREAD
SLIGHTLY NEWD WITH TIME.




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