Severe Storm Outlook Narrative (AC)
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000
ACUS11 KWNS 271412
SWOMCD
SPC MCD 271412
AZZ000-UTZ000-NVZ000-CAZ000-271615-

MESOSCALE DISCUSSION 1769
NWS STORM PREDICTION CENTER NORMAN OK
0912 AM CDT SAT SEP 27 2014

AREAS AFFECTED...NV...AZ...UT

CONCERNING...SEVERE THUNDERSTORM WATCH 507...

VALID 271412Z - 271615Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 507
CONTINUES.

SUMMARY...STRONG TO ISOLATED SEVERE STORMS REMAIN POSSIBLE FROM
NORTHWEST AZ INTO SOUTHWEST UT EARLY THIS MORNING.

DISCUSSION...CYCLONICALLY-CURVED JET WITH MID-LEVEL SPEED MAX AROUND
75KT WAS ROUNDING THE BASE OF A SUBSTANTIAL MID/UPPER TROUGH OVER CA
THIS MORNING. ABUNDANTLY MOIST AIRMASS /PW VALUES 1-1.5 INCHES/
STREAMING NORTH AHEAD OF THIS SYSTEM WAS CONTRIBUTING TO A
PERSISTENT BAND OF VIGOROUS CONVECTION FOCUSED ALONG A LOW-LEVEL
CONFLUENCE ZONE OVER WESTERN AZ WHERE DEEP-LAYER ASCENT WAS
MAXIMIZED AHEAD OF THE UPPER TROUGH. DOWNSLOPE FLOW OFF THE SOUTHERN
SIERRA CREST HAS LIKELY CONTRIBUTED TO A DRYLINE ON THE WESTERN EDGE
OF THE STRONGER CONVECTION AND EXPECT SEVERE THREAT HAS ENDED FOR
NOW ACROSS SOUTHERN NV.

EFFECTIVE DEEP-LAYER SHEAR OF 35-40KT WILL CONTINUE TO SUPPORT
TRANSIENT SUPERCELL STRUCTURES AND LINE SEGMENTS TRACKING
NORTH-NORTHEAST AROUND 30KT AS STRONG LIFT ACTS ON MOIST AND
SUFFICIENTLY UNSTABLE AIRMASS FROM WESTERN AZ NORTHWARD INTO UT. A
FEW OF THESE STORMS COULD PRODUCE DAMAGING WINDS...MARGINALLY SEVERE
HAIL AROUND 1 INCH...AND PERHAPS A BRIEF TORNADO. TRAINING NATURE OF
THE CONVECTION WILL ALSO RESULT IN LOCALIZED FLASH FLOODING.

..CARBIN/MEAD.. 09/27/2014

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...FGZ...SLC...PSR...VEF...LKN...

LAT...LON   34131241 34131416 36131512 38131608 38151423 38131240
            36131154 34131066 34131241



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