Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS03 KWNS 250731
SWODY3
SPC AC 250730

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT FRI JUL 25 2014

VALID 271200Z - 281200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF THE OH VALLEY
EWD TO THE MID ATLANTIC...

...SUMMARY...
VERY LARGE HAIL...DAMAGING WINDS AND A FEW TORNADOES WILL ALL BE
POSSIBLE ON SUNDAY ACROSS MUCH OF THE OHIO VALLEY AND EXTENDING
EASTWARD TO THE MID ATLANTIC STATES. THE GREATEST RISK WILL BE
ACROSS MUCH OF KENTUCKY...SOUTHERN INDIANA...OHIO...WEST VIRGINA AND
TENNESSEE.

...SYNOPSIS...
A STRONG SUMMERTIME UPPER TROUGH WILL SWING SEWD ACROSS THE GREAT
LAKES WITH A BROAD AREA OF CYCLONIC FLOW ALOFT STRETCHING FROM THE
UPPER MS VALLEY EWD TO THE ATLANTIC COAST. WINDS ALOFT WILL BE
CHARACTERIZED BY 60 TO 80 KT MID TO UPPER-LEVEL FLOW WHICH WILL MOVE
INTO THE OH VALLEY BY 00Z. BY LATE AFTERNOON...LOW PRESSURE WILL
SETTLE OVER LOWER MI WITH A COLD FRONT EXTENDING SWWD FROM INDIANA
INTO SRN MO.

AHEAD OF THE FRONT...A VERY MOIST AND UNSTABLE AIR MASS WILL EXIST
WITHIN A SHEARED ENVIRONMENT QUITE FAVORABLE FOR SEVERE STORMS.

...OH/TN VALLEYS EWD TO THE MID ATLANTIC...
A SEVERE MCS CAPABLE OF DAMAGING WINDS MAY BE ONGOING ACROSS SRN
OH...NRN KY AND WV SUNDAY MORNING. THIS SYSTEM MAY CONTINUE EWD
ACROSS WV AND INTO VA...BUT WOULD LIKELY WEAKEN FROM ITS EARLIER
INTENSITY. STILL...A WIND/HAIL THREAT WOULD BE PRESENT ACROSS VA AND
THE DELMARVA...AIDED BY STRONG MEAN WLY FLOW ALOFT.

BEHIND THE MORNING ACTIVITY...HEATING AND MOISTENING WILL OCCUR
BENEATH STEEP LAPSE RATES ALOFT...RESULTING IN STRONG INSTABILITY.
CONDITIONALLY...VERY LARGE HAIL WILL BE POSSIBLE OVER A LARGE AREA
OWING TO THE JUXTAPOSITION OF SAID THERMODYNAMICS AND DEEP-LAYER
SHEAR ON THE ORDER OF 50 KT. HODOGRAPHS APPEAR TO BE LARGELY
STRAIGHT-LINE BUT LOW-LEVEL SHEAR MAY BE MAXIMIZED ALONG ANY OUTFLOW
BOUNDARY FROM EARLIER STORMS...WITH SRH FORECAST TO BE HIGHEST
ACROSS SRN OH...ERN KY...AND WV. A STRONG TORNADO IS CONDITIONALLY
POSSIBLE NEAR SAID OUTFLOW BOUNDARY.

AFTERNOON STORM DEVELOPMENT WILL BE MOST LIKELY TO OCCUR FIRST ALONG
THE PRIMARY COLD FRONT...FROM NRN INDIANA INTO NRN OH...AND
EXTENDING NEWD ACROSS WRN NY. STORMS SHOULD THEN FILL IN SWWD AROUND
00Z ACROSS KY. SUPERCELLS WILL BE THE DOMINANT STORM MODE WITH VERY
LARGE HAIL AND A TORNADO OR TWO WITH THE MOST DEVIANTLY-MOVING
CELLS...ESPECIALLY THOSE NEAR ANY PRE-EXISTING BOUNDARIES.

SOME CELL MERGERS MAY EVENTUALLY OCCUR...WITH DAMAGING WINDS
EXTENDING SEWD ACROSS TN AND FAR WRN VA BY EVENING.

..JEWELL.. 07/25/2014




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