Severe Storm Outlook Narrative (AC)
Issued by NWS

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004
ACUS02 KWNS 250555
SWODY2
SPC AC 250554

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1254 AM CDT SUN SEP 25 2016

VALID 261200Z - 271200Z

...THERE IS A MRGL RISK OF SVR TSTMS ACROSS THE UPPER OH
VALLEY/APPALACHIANS...

...SUMMARY...
A FEW STRONG TO SEVERE THUNDERSTORMS MAY OCCUR MONDAY ACROSS
PORTIONS OF THE UPPER OHIO RIVER VALLEY AND NEARBY APPALACHIANS
VICINITY.

...UPPER OH RIVER VALLEY/APPALACHIANS VICINITY INCLUDING WV/PA...
AN UPPER TROUGH WILL BECOME INCREASINGLY CLOSED OVER THE GREAT LAKES
AND ONTARIO ON MONDAY...WITH A RELATED STEADY STRENGTHENING OF
DEEP-LAYER SOUTHWESTERLY WINDS ACROSS THE REGION IN CONJUNCTION WITH
AN EAST/NORTHEASTWARD PIVOT OF THE BASE OF THE UPPER TROUGH. AS THIS
OCCURS...MODEST LOW-LEVEL MOISTENING WILL PRECEDE AN EASTWARD-MOVING
COLD FRONT...WITH THE POSSIBILITY OF NEAR 60F SURFACE DEWPOINTS
REACHING AS FAR NORTH-NORTHEAST AS FAR EASTERN OH/WESTERN PA WITHIN
A RELATIVELY NARROW PRE-FRONTAL MOIST CORRIDOR.

WHILE MID-LEVEL LAPSE RATES WILL NOT BE STEEP AND THE POSSIBILITY OF
EARLY-DAY CLOUD COVER/SCATTERED PRECIPITATION CASTS UNCERTAINTY...IT
APPEARS THAT AT LEAST WEAK PRE-FRONTAL DESTABILIZATION SHOULD OCCUR
WITHIN THE NARROW WARM/MOIST SECTOR WEST OF THE APPALACHIANS. IN THE
PRESENCE OF AMPLE FORCING FOR ASCENT AND INCREASINGLY STRONG
DEEP-LAYER SOUTHWESTERLY WINDS /STRENGTHENING TO 50+ KT AT 500
MB/...LINEAR BANDS OF CONVECTION SHOULD EVOLVE/INTENSIFY MONDAY
AFTERNOON WITH SOME POTENTIAL FOR LOCALIZED WIND DAMAGE THROUGH THE
EARLY EVENING HOURS.

...TN VALLEY/SOUTHERN APPALACHIANS TO FL...
THESE REGIONS WILL BE REMOVED FROM THE STRONGER HEIGHT
FALLS/DEEP-LAYER SHEAR...BUT A MODERATELY UNSTABLE AIR MASS MAY
NONETHELESS ALLOW FOR SOME STRONGER STORMS MONDAY AFTERNOON...EITHER
SEMI-FOCUSED NEAR THE ADVANCING FRONT ACROSS THE TN VALLEY/SOUTHERN
APPALACHIANS OR WITH SEA BREEZE CIRCULATIONS ACROSS THE FL
PENINSULA. LOCALLY STRONGER WIND GUSTS BE THE MAIN POTENTIAL.

..GUYER.. 09/25/2016

$$



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