Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS01 KWNS 121941
SWODY1
SPC AC 121940

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0140 PM CST FRI FEB 12 2016

VALID 122000Z - 131200Z

...NO SVR TSTM AREAS FORECAST...

...SUMMARY...
A FEW THUNDERSTORMS MAY OCCUR TODAY INTO TONIGHT OVER PARTS OF
WESTERN WASHINGTON.

...20Z OUTLOOK UPDATE...
NO CHANGES HAVE BEEN MADE TO THE ONGOING CONVECTIVE OUTLOOK.

..KERR.. 02/12/2016

.PREV DISCUSSION... /ISSUED 0933 AM CST FRI FEB 12 2016/

...SYNOPTIC SETUP...
VERY SLOWLY PROGRESSIVE WRN RIDGE/ERN TROUGH PATTERN WILL PERSIST
THROUGH SAT. ON WRN FLANK OF THE RIDGE...TWO-PART SHORTWAVE TROUGH
NOW LOCATED OFF THE WA CST BETWEEN 130 AND 140W WILL DEAMPLIFY AS
ITS CONTINUES GENERALLY E INTO WA/ORE. POLAR AIR WILL ONCE AGAIN
DOMINATE THE LWR LVLS E OF THE RCKYS...WITH MODEST ONSHORE FLOW
CONFINED TO THE PAC NW.

...WRN WA TODAY INTO TNGT...
LEAD PORTION OF AFOREMENTIONED SHORTWAVE TROUGH EXPECTED TO CONTINUE
SHEARING NE ACROSS FAR WRN WA AND WRN BC LATER TODAY.
FEEBLE...SLIGHTLY ELEVATED INSTABILITY MAY BE ACCOMPANIED BY AN
OCCASIONAL LIGHTNING STRIKE IN THE ASSOCIATED FRONTAL BAND...BUT
APPRECIABLE THUNDER IS NOT EXPECTED.

A SOMEWHAT GREATER CHANCE FOR ISOLD THUNDER WILL OCCUR LATER TODAY
INTO TNGT AS ASCENT/MID-LVL COOLING INCREASE WITH THE APPROACH OF
THE SECOND PART OF THE LARGER-SCALE TROUGH. THE LATTER DISTURBANCE
IS NEARING 130W ATTM...AND SHOULD SWEEP INLAND LATER TODAY.
ATTENDANT STEEPENING OF LOW TO MID-LVL LAPSE RATES AND UPSLOPE FLOW
SHOULD SUPPORT SUFFICIENT DEEPENING OF EXISTING CONVECTION TO YIELD
THUNDER.

$$


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