000
ACUS11 KWNS 280329
SWOMCD
SPC MCD 280328
NJZ000-MDZ000-DEZ000-VAZ000-NCZ000-280530-

MESOSCALE DISCUSSION 1494
NWS STORM PREDICTION CENTER NORMAN OK
1028 PM CDT SUN JUL 27 2014

AREAS AFFECTED...PARTS OF SRN NJ...DE...ERN MD AND CNTRL/ERN
VA...INCLUDING THE DISTRICT OF COLUMBIA...AND N CNTRL NORTH CAROLINA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 280328Z - 280530Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...IT STILL APPEARS POSSIBLE THAT A SUBSTANTIVE SEVERE
WEATHER THREAT COULD DEVELOP OVERNIGHT ACROSS THE MID ATLANTIC COAST
REGION.  CONVECTIVE TRENDS WILL CONTINUE TO BE CLOSELY MONITORED FOR
THIS POSSIBILITY...AND THE NEED FOR ONE OR MORE SEVERE WEATHER
WATCHES.

DISCUSSION...AS A SEASONABLY STRONG SHORT WAVE TROUGH CONTINUES TO
TURN EAST SOUTHEAST OF THE UPPER GREAT LAKES REGION...INCREASINGLY
CYCLONIC AND STRENGTHENING /50-70 KT/ MID-LEVEL FLOW APPEARS LIKELY
TO NOSE EAST OF THE CENTRAL APPALACHIANS THROUGH THE MID ATLANTIC
COAST BY THE 06-09Z TIME FRAME.  VERTICAL SHEAR IS ALREADY BECOMING
SUFFICIENTLY STRONG FOR ORGANIZED SEVERE CONVECTION IN THE PRESENCE
OF A CONDITIONALLY UNSTABLE ENVIRONMENT CHARACTERIZED BY SEASONABLY
HIGH MOISTURE CONTENT.  SOME FURTHER STRENGTHENING AND BACKING OF
LOW-LEVEL FLOW FIELDS ALSO APPEARS POSSIBLE AS A SURFACE LOW DEEPENS
TO THE LEE OF THE LOWER GREAT LAKES.  GIVEN THESE CONDITIONS...IT
DOES NOT APPEAR OUT OF THE QUESTION THAT ONGOING SCATTERED
THUNDERSTORM ACTIVITY...NOW SPREADING ACROSS THE UPPER OHIO
VALLEY/CENTRAL APPALACHIANS REGION...COULD GRADUALLY
CONSOLIDATE/ORGANIZE AND INTENSIFY AS IT DEVELOPS EASTWARD ACROSS
THE MID ATLANTIC PIEDMONT AND COASTAL PLAIN OVERNIGHT.  IF THIS
OCCURS...IT WOULD PROBABLY BE ACCOMPANIED BY A CONSIDERABLE RISK FOR
POTENTIALLY DAMAGING WIND GUSTS AND...PERHAPS...A COUPLE OF
TORNADOES.

..KERR/EDWARDS.. 07/28/2014

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...PHI...AKQ...LWX...RAH...RNK...

LAT...LON   37847891 38087811 38597751 38827682 39057641 39407560
            39757505 39677457 38067559 36927678 35937846 35847970
            36188062 37007972 37847891