Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS02 KWNS 201725
SWODY2
SPC AC 201725

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1225 PM CDT SUN APR 20 2014

VALID 211200Z - 221200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF CENTRAL AND
NERN TX...

...SUMMARY...
SCATTERED STRONG STORMS...A FEW POSSIBLY SEVERE...ARE EXPECTED TO
DEVELOP FROM THE HILL COUNTRY OF CENTRAL TEXAS INTO NORTHEASTERN
TEXAS DURING THE DAY MONDAY.

...SYNOPSIS...
PHASING OF NRN AND SRN STREAM VORTICITY MAXIMA OVER THE CENTRAL U.S.
WILL CONTINUE THROUGH THE DAY 2 PERIOD...WITH AN INCREASINGLY
CONSOLIDATED TROUGH PROGGED TO SHIFT EWD INTO THE ERN HALF OF THE
COUNTRY.  AS THIS OCCURS...A WEAK COOL FRONT WILL PROGRESS EWD
ACROSS THE MIDWEST AND SEWD ACROSS THE MID MS/LOWER MO/RED RIVER
VALLEYS INTO AR/TX INTO THE EVENING HOURS.  THIS FRONT WILL FOCUS AN
AREA OF SHOWER/STORM DEVELOPMENT CENTERED OVER TX DURING THE
AFTERNOON.

ELSEWHERE...A MUCH STRONGER UPPER TROUGH CROSSING THE ERN PACIFIC
WILL APPROACH THE W COAST LATE...WITH A COLD FRONT CROSSING CA AND
THE GREAT BASIN THROUGH THE PERIOD.

...THE TX HILL COUNTRY ENEWD INTO NERN TX...
DIURNAL DESTABILIZATION IS FORECAST ACROSS A LARGE PORTION OF E TX
DAY 2...AS AFTERNOON HEATING OF A MODEST BOUNDARY LAYER MOISTURE
/UPPER 50S TO LOW 60S DEWPOINTS/ COMMENCES BENEATH STEEP MID-LEVEL
LAPSE RATES SPREADING INTO CENTRAL TX.  WITH 1500 TO 2000 J/KG
MIXED-LAYER CAPE EXPECTED TO EVOLVE THROUGH THE AFTERNOON ABOVE A
DEEPENING/WELL-MIXED BOUNDARY LAYER...ISOLATED STORMS ARE FORECAST
TO DEVELOP NEAR AND AHEAD OF THE WEAK/SEWD-MOVING COOL FRONT.

WITH RELATIVELY MODEST MID-LEVEL WLYS /AROUND 25 TO 30 KT AT H5/ --
PARTICULARLY ACROSS CENTRAL TX WHERE THE MOST UNSTABLE ENVIRONMENT
IS FORECAST...ORGANIZED/SUSTAINED UPDRAFTS ARE EXPECTED.  COOL
MID-LEVEL TEMPERATURES/STEEP LAPSE RATES SUPPORT A HAIL RISK WITH
STRONGER STORMS GIVEN THE KINEMATIC ENVIRONMENT...WHILE THE DEEP
MIXED LAYER ALSO SUGGESTS POTENTIAL FOR LOCALLY DAMAGING WINDS.

STORMS MAY LOCALLY GROW UPSCALE INTO MULTICELL CLUSTERS INTO LATE
AFTERNOON...POSSIBLY ENHANCING THE RISK FOR DAMAGING WINDS LOCALLY.
WITH TIME HOWEVER...THE LOSS OF DAYTIME HEATING WILL YIELD A FAIRLY
RAPID STABILIZATION OF THE BOUNDARY LAYER...AND A SUBSEQUENT
DECREASE IN CONVECTIVE INTENSITY/COVERAGE.

..GOSS.. 04/20/2014




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