Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS03 KWNS 010705
SWODY3
SPC AC 010703

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0203 AM CDT WED OCT 01 2014

VALID 031200Z - 041200Z

...NO SVR TSTM AREAS FORECAST...

...SUMMARY...
SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG/AHEAD OF COLD
FRONT FROM THE OHIO VALLEY TO THE GULF COAST FRIDAY...ESPECIALLY THE
SOUTHEASTERN US.

...EASTERN U.S...

STRONG MID-LEVEL SPEED MAX WILL INTENSIFY AS IT DIGS INTO THE BASE
OF MIDWEST UPPER TROUGH.  LATEST MODEL GUIDANCE SUGGEST 100KT+ 500MB
SPEED MAX WILL ROUND THE BASE OF THE TROUGH OVER THE LOWER OH VALLEY
THEN EJECT NNEWD INTO SERN ONTARIO LATE IN THE PERIOD.  SFC LOW IS
EXPECTED TO DEEPEN OVER THE UPPER GREAT LAKES AND THE TRAILING COLD
FRONT WILL SHARPEN AS IT SURGES INTO THE OH VALLEY EARLY IN THE
PERIOD.  THERE IS SOME CONCERN THAT ROBUST THUNDERSTORMS COULD
EVOLVE BY MID-DAY ACROSS OH/WRN PA AS LARGE SCALE FORCING SHOULD
ENCOURAGE CONVECTION ALONG THE WIND SHIFT.  HOWEVER...IT/S NOT CLEAR
HOW MUCH MOISTURE WILL ADVANCE INTO THIS PORTION OF THE OH VALLEY
PRIOR TO FRONTAL PASSAGE AND INSTABILITY MAY BE TOO WEAK TO WARRANT
STRONG UPDRAFTS.  FOR THIS REASON WILL NOT INTRODUCE SEVERE PROBS.
IF IT BECOMES APPARENT A NARROW CORRIDOR OF MODEST INSTABILITY WILL
DEVELOP ACROSS THIS REGION THEN LOW SEVERE PROBS MAY BE ADDED TO
ACCOUNT FOR LOCALLY DAMAGING WINDS WITH LOW-TOPPED CONVECTION.

FARTHER SOUTH...SCT THUNDERSTORMS ARE EXPECTED ACROSS MUCH OF THE
GULF STATES/SERN U.S. WHERE AMPLE MOISTURE/INSTABILITY WILL BE
PRESENT FOR CONVECTION TO DEVELOP WITH FRONTAL UPLIFT.  GIVEN THE
RELATIVELY WEAK LAPSE RATES IT APPEARS MOST STORMS SHOULD REMAIN
BELOW SEVERE LEVELS WITH STRONGEST CONVECTION PRODUCING MOSTLY
SUB-SEVERE WIND GUSTS.

..DARROW.. 10/01/2014




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