2% Tornado Risk for Southern California 2/16/09
The Storm Prediction Center in Norman, Oklahoma has issued a 2% Tornado Risk for Southern California in response the the major storm system barreling down on the area on Monday, February 16, 2009. Here are the details:
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SPC AC 160538
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1138 PM CST SUN FEB 15 2009
VALID 161200Z - 171200Z
...NO SVR TSTM AREAS FORECAST...
...SRN CA...
AN UPPER-LEVEL LOW OFF THE COAST OF NRN CA WILL MOVE SLOWLY SEWD
TODAY. PLENTIFUL LARGE-SCALE ASCENT SOUTHEAST OF THE LOW AND COLD
AIR ALOFT IN THE CORE OF THE SYSTEM WILL PROVIDE SUPPORT FOR
ISOLATED THUNDERSTORMS TODAY FROM THE CNTRL CA COAST AND SRN
SACRAMENTO VALLEY SSEWD TO THE LA BASIN. LIFT SHOULD BE MAXIMIZED IN
LA BASIN THIS AFTERNOON AS THE EXIT REGION OF A MID-LEVEL JET ROUNDS
THE BASE OF THE TROUGH AND MOVES OVER SRN CA. FORECAST SOUNDINGS
ACROSS THE LA BASIN THIS AFTERNOON SHOW STRONG VERTICAL SHEAR
ASSOCIATED WITH THE MID-LEVEL JET. THIS ALONG WITH THE COLD AIR
ALOFT MAY BE ENOUGH FOR A HAIL THREAT WITH THUNDERSTORMS THAT
DEVELOP LATE THIS MORNING THROUGH THE AFTERNOON WHEN SFC TEMPS WILL
BE A BIT WARMER. IN ADDITION...THE MODELS MOVE A 40 TO 50 KT
LOW-LEVEL JET SSEWD FROM THE CNTRL CA COAST SEWD INTO THE LA BASIN
TODAY. THIS ALONG WITH OROGRAPHIC EFFECTS FROM THE SURROUNDING
MOUNTAIN RANGES IN THE LA BASIN WILL LOCALLY ENHANCE LOW-LEVEL SHEAR
SUPPORTING A MARGINAL TORNADO THREAT WITH LOW-TOPPED THUNDERSTORMS
THAT INITIATE LATE THIS MORNING OR EARLY THIS AFTERNOON.
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Although I am recovering from the flu, I may venture out for a quick chase as I have a good feeling that I may see some form of funnel today. The LA Basin is a large area so this is going to be a good test for me to interpret the soundings and other factors to help put me in the right spot. Problem is, the geography of SoCal is complex and our mountains can create havoc on wind shears, but there are certain convergence zones and other types of land effects that will help me pinpoint the right place to be in. Let's see how I do.....
----------------------
SPC AC 160538
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1138 PM CST SUN FEB 15 2009
VALID 161200Z - 171200Z
...NO SVR TSTM AREAS FORECAST...
...SRN CA...
AN UPPER-LEVEL LOW OFF THE COAST OF NRN CA WILL MOVE SLOWLY SEWD
TODAY. PLENTIFUL LARGE-SCALE ASCENT SOUTHEAST OF THE LOW AND COLD
AIR ALOFT IN THE CORE OF THE SYSTEM WILL PROVIDE SUPPORT FOR
ISOLATED THUNDERSTORMS TODAY FROM THE CNTRL CA COAST AND SRN
SACRAMENTO VALLEY SSEWD TO THE LA BASIN. LIFT SHOULD BE MAXIMIZED IN
LA BASIN THIS AFTERNOON AS THE EXIT REGION OF A MID-LEVEL JET ROUNDS
THE BASE OF THE TROUGH AND MOVES OVER SRN CA. FORECAST SOUNDINGS
ACROSS THE LA BASIN THIS AFTERNOON SHOW STRONG VERTICAL SHEAR
ASSOCIATED WITH THE MID-LEVEL JET. THIS ALONG WITH THE COLD AIR
ALOFT MAY BE ENOUGH FOR A HAIL THREAT WITH THUNDERSTORMS THAT
DEVELOP LATE THIS MORNING THROUGH THE AFTERNOON WHEN SFC TEMPS WILL
BE A BIT WARMER. IN ADDITION...THE MODELS MOVE A 40 TO 50 KT
LOW-LEVEL JET SSEWD FROM THE CNTRL CA COAST SEWD INTO THE LA BASIN
TODAY. THIS ALONG WITH OROGRAPHIC EFFECTS FROM THE SURROUNDING
MOUNTAIN RANGES IN THE LA BASIN WILL LOCALLY ENHANCE LOW-LEVEL SHEAR
SUPPORTING A MARGINAL TORNADO THREAT WITH LOW-TOPPED THUNDERSTORMS
THAT INITIATE LATE THIS MORNING OR EARLY THIS AFTERNOON.
-------------------------
-------------------------
Although I am recovering from the flu, I may venture out for a quick chase as I have a good feeling that I may see some form of funnel today. The LA Basin is a large area so this is going to be a good test for me to interpret the soundings and other factors to help put me in the right spot. Problem is, the geography of SoCal is complex and our mountains can create havoc on wind shears, but there are certain convergence zones and other types of land effects that will help me pinpoint the right place to be in. Let's see how I do.....
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Update 6:30am 2/16/09....... SPC now issued a SLGT and 15% hail for SoCal today.... niiiice....
posted by Will Wilkens at
12:06 AM
