Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS01 KWNS 251925
SWODY1
SPC AC 251923

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0123 PM CST THU DEC 25 2014

VALID 252000Z - 261200Z

...NO TSTM AREAS FORECAST...
..DARROW.. 12/25/2014

.PREV DISCUSSION... /ISSUED 1015 AM CST THU DEC 25 2014/

...SYNOPTIC SETUP...
E CST TROUGH WILL PROGRESS STEADILY E INTO THE ATLANTIC...LEAVING A
BROAD SWATH OF ZONAL FLOW ACROSS THE ERN HALF OF THE U.S. FARTHER
W...GRT BASIN TROUGH SHOULD AMPLIFY SEWD INTO A CLOSED LOW OVER THE
FOUR CORNERS EARLY FRI AS UPSTREAM RIDGE BUILDS NEWD INTO BC.
RELATIVELY MILD BUT DRY AIR WILL PREVAIL OVER MOST OF THE CONUS AT
LWR LVLS.

...AZ AREA LATER TODAY/TNGT...
CONTINUED SE MOVEMENT/AMPLIFICATION OF GRT BASIN TROUGH...COUPLED
WITH DIURNAL HEATING...WILL YIELD A CORRIDOR OF WEAK SFC-BASED
BUOYANCY OVER NRN AZ LATER TODAY. GIVEN COMPARATIVELY COOL MID-LVL
TEMPS /AOB MINUS 25C AT 500 MB/ AND PRESENCE OF TERRAIN
CIRCULATIONS...SETUP MAY SUPPORT SUFFICIENT DEEPENING OF SCTD...
DIURNALLY-ENHANCED CONVECTION TO YIELD SPORADIC LIGHTNING
STRIKES...BUT VERY LIMITED MOISTURE SHOULD KEEP SUCH ACTIVITY VERY
ISOLD.

A SEPARATE AREA OF DEEPENING CONVECTION AND POSSIBLE THUNDER MAY
EVOLVE LATE TODAY INTO TNGT ACROSS SRN AND SE AZ...WHERE UPR
DIVERGENCE WILL STRENGTHEN AS EXIT REGION OF JET STREAK NOW OVER THE
CNTRL CA CST OVERSPREADS REGION. LOW-LVL MOISTURE WILL REMAIN SCANT.
BUT RIBBON OF MODEST MID-LVL MOISTURE /PW AOA 0.50 INCH/ SPREADING
EWD IN BASE OF THE TROUGH...IN CONJUNCTION WITH INCREASING FORCING
FOR ASCENT...COULD YIELD A BAND OF MID-LVL CONVECTION SUFFICIENTLY
DEEP TO PRODUCE A COUPLE LIGHTNING STRIKES THROUGH EARLY FRI.



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