Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS02 KWNS 261719
SWODY2
SPC AC 261718

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1218 PM CDT MON SEP 26 2016

VALID 271200Z - 281200Z

...NO SVR TSTM AREAS FORECAST...

...SUMMARY...
THE RISK FOR SEVERE THUNDERSTORMS STILL APPEARS NEGLIGIBLE ACROSS
THE U.S. TUESDAY THROUGH TUESDAY NIGHT.

...SYNOPSIS...
MODELS INDICATE THAT THE DEEP CYCLONE OVER NORTHERN ONTARIO AND THE
UPPER GREAT LAKES REGION WILL BECOME INCREASINGLY OCCLUDED BY 12Z
TUESDAY.  THROUGH THE DAY TUESDAY INTO 12Z WEDNESDAY...SURFACE
PRESSURE/HEIGHTS NEAR THE CENTER OF THE CIRCULATION ARE FORECAST TO
SLOWLY RISE...WHILE IT GRADUALLY REDEVELOPS SOUTH SOUTHEAST OF LAKE
SUPERIOR AND UPPER MICHIGAN...DOWNSTREAM OF AMPLIFIED RIDGING WITHIN
THE PRIMARY BRANCH OF MID-LATITUDE WESTERLIES.  SOME SUPPRESSION OF
THIS RIDGING APPEARS POSSIBLE WITH THE INLAND MIGRATION OF A
SIGNIFICANT SHORT WAVE IMPULSE ACROSS THE CANADIAN ROCKIES...TOWARD
THE NORTHWEST TERRITORIES...BUT MODELS SUGGEST THAT THIS WILL BE
LIMITED/SHORT-LIVED...AHEAD OF ANOTHER SIGNIFICANT IMPULSE DIGGING
ACROSS THE NORTHEASTERN PACIFIC.  AND IT APPEARS THAT THE GREAT
LAKES MID/UPPER LOW CENTER MAY BEGIN TO BECOME CUT OFF FROM THE
WESTERLIES.

WELL SOUTH OF THE STRONGER WESTERLIES...A MID/UPPER CLOSED LOW NOW
MIGRATING SLOWLY WESTWARD ACROSS BAJA APPEARS LIKELY TO GRADUALLY
TURN NORTHWARD INTO SOUTHERN CALIFORNIA AND THE LOWER COLORADO
VALLEY.  THIS MAY BE ACCOMPANIED BY SOME MOISTENING...WEAK
DESTABILIZATION AND A RISK FOR SCATTERED THUNDERSTORM ACTIVITY
TUESDAY INTO TUESDAY NIGHT.

OTHERWISE...THE RISK FOR THUNDERSTORM ACTIVITY IS EXPECTED TO BE
LARGELY CONFINED TO AREAS ALONG/SOUTH OF A COLD FRONT ASSOCIATED
WITH THE GREAT LAKES CYCLONE.  BY OR SHORTLY AFTER 12Z TUESDAY...THE
FRONT APPEARS LIKELY TO ADVANCE INTO/ACROSS FAR SOUTHEASTERN NEW
ENGLAND AND MID ATLANTIC COASTAL AREAS...WHILE STALLING NEAR OR TO
THE EAST OF THE SOUTHERN APPALACHIANS INTO WESTERN GULF COASTAL
AREAS.  GENERALLY MODEST TO WEAK DESTABILIZATION AND/OR WEAK
VERTICAL SHEAR SHOULD MINIMIZE ANY SEVERE WEATHER POTENTIAL.

..KERR.. 09/26/2016

$$



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