Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS01 KWNS 251245
SWODY1
SPC AC 251244

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0744 AM CDT FRI JUL 25 2014

VALID 251300Z - 261200Z

...NO SVR TSTM AREAS FORECAST...

...SUMMARY...
ISOLATED LARGE HAIL AND DAMAGING WIND GUSTS WILL BE POSSIBLE TODAY
INTO TONIGHT WITH A COUPLE OF THUNDERSTORM CLUSTERS ACROSS THE
MIDDLE AND UPPER MISSISSIPPI VALLEY REGION.  OTHER ISOLATED STRONG
WIND GUSTS WILL ALSO BE POSSIBLE THIS AFTERNOON ACROSS CENTRAL AND
EASTERN SOUTH CAROLINA...THE CENTRAL HIGH PLAINS...AND SOUTH CENTRAL
AND SOUTHWEST ARIZONA.

...MIDDLE AND UPPER MS VALLEY REGION THROUGH TONIGHT...
A MIDLEVEL LOW WILL MOVE SLOWLY EWD TODAY OVER SRN SK...AND THEN
BEGIN TO MOVE ESEWD TONIGHT AFTER CRESTING THE MIDLEVEL RIDGE OVER
THE NRN PLAINS.  MEANWHILE...A SERIES OF EMBEDDED LOW-AMPLITUDE
SPEED MAXIMA WILL TRANSLATE FROM THE SRN PERIPHERY OF THE MIDLEVEL
LOW TO THE UPPER MS VALLEY.  ONE SUCH WAVE WILL CONTINUE SEWD FROM
WRN IA THIS MORNING...WITH AN ASSOCIATED SEGMENT OF THE LLJ
SUPPORTING WAA AND CLUSTERS OF ELEVATED THUNDERSTORMS.  ISOLATED
LARGE HAIL AND/OR DAMAGING GUSTS MAY OCCUR WITH THE STRONGER STORMS
ON THE SRN AND WRN FLANKS OF THE CLUSTERS TODAY AS THE LOW LEVELS
DESTABILIZE FROM THE W.  HOWEVER...A WARM EML WILL LIKELY CAP TRUE
SURFACE-BASED THUNDERSTORM DEVELOPMENT ACROSS IA/NRN MO.

LATER THIS AFTERNOON INTO TONIGHT...ANOTHER SPEED MAX WILL PROGRESS
FROM THE DAKOTAS TO MN/WI.  ASCENT IN ADVANCE OF THIS WAVE MAY
SUPPORT THE DEVELOPMENT OF ANOTHER SEWD-MOVING CLUSTER OF STORMS
ACROSS WI AND VICINITY WITH A MARGINAL SEVERE RISK.  LIKE AREAS
FARTHER TO THE S...LOW-LEVEL DESTABILIZATION WILL LIKELY BE OFFSET
BY A STRENGTHENING EML...SUCH THAT SURFACE-BASED THUNDERSTORM
DEVELOPMENT IS IN QUESTION.

...CENTRAL/ERN SC AND VICINITY THIS AFTERNOON...
A LINGERING FRONT/DIFFERENTIAL HEATING ZONE AND WEAK ASSOCIATED
MIDLEVEL TROUGH...ALONG WITH LOCAL SEA BREEZE CIRCULATIONS...WILL
FOCUS THUNDERSTORM DEVELOPMENT THIS AFTERNOON.  THOUGH LAPSE RATES
WILL BE RATHER POOR ALOFT...MLCAPE OF 1500-2000 J/KG AND PW VALUES
NEAR 2 INCHES COULD BE SUFFICIENT FOR A FEW STRONG OUTFLOW GUSTS
WITH WET MICROBURSTS.

...CENTRAL HIGH PLAINS THIS AFTERNOON INTO EARLY TONIGHT...
STRONG SURFACE HEATING AND MIXING OF RESIDUAL LOW-LEVEL MOISTURE
WILL RESULT IN WEAK-MODERATE BUOYANCY AND INVERTED-V PROFILES THIS
AFTERNOON ACROSS ERN CO...WHERE A FEW HIGH-BASED STORMS WITH STRONG
OUTFLOW GUSTS WILL BE POSSIBLE.  REMNANTS OF THIS CONVECTION COULD
SURVIVE INTO WRN KS THROUGH EARLY TONIGHT.  FARTHER N INTO SE
WY...VERTICAL SHEAR WILL BE STRONGER BUT INSTABILITY WILL ONLY BE
MARGINAL FOR AN ISOLATED LARGE HAIL/DAMAGING WIND RISK THIS
AFTERNOON/EVENING.

...S CENTRAL/SW AZ THIS AFTERNOON...
STRONG SURFACE HEATING AND AN INCREASE IN LOW-LEVEL MOISTURE WILL
LEAD TO AFTERNOON MLCAPE VALUES AOA 1500 J/KG ACROSS THE LOWER
DESERTS OF S CENTRAL AND SW AZ...WHERE THUNDERSTORM DEVELOPMENT WILL
BE POSSIBLE.  THERMODYNAMIC PROFILES WILL FAVOR HYBRID
MICROBURSTS...WITH A RISK FOR ISOLATED STRONG/DAMAGING OUTFLOW GUSTS
AND BLOWING DUST.

..THOMPSON/JIRAK.. 07/25/2014



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