As we have been discussing, the weather continues to head toward a more unstable atmosphere. As of 5 PM EDT the Storm Prediction Center has issued a Severe Thunderstorm Watch for much of Central Virginia that is not covered by a tornado watch already. The outline areas are below.

URGENT – IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 486
NWS STORM PREDICTION CENTER NORMAN OK
500 PM EDT WED JUL 4 2007

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

A SMALL PART OF NORTHERN NORTH CAROLINA
CENTRAL AND SOUTHERN VIRGINIA
SOUTHEASTERN WEST VIRGINIA

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 500 PM UNTIL
1000 PM EDT.

HAIL TO 1.5 INCHES IN DIAMETER…THUNDERSTORM WIND GUSTS TO 70
MPH…AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 60
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 40 MILES SOUTH
SOUTHWEST OF BLUEFIELD WEST VIRGINIA TO 45 MILES EAST SOUTHEAST
OF CHARLOTTESVILLE VIRGINIA. FOR A COMPLETE DEPICTION OF THE
WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).

REMEMBER…A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION…CONTINUE…WW 482…WW 483…WW
484…WW 485…

DISCUSSION…WIDELY SCTD STORMS/POSSIBLE SUPERCELLS EXPECTED TO
PERSIST/DEVELOP IN MODERATELY SHEARED LOW LVL THERMAL AXIS ON SRN
FRINGE OF DIFFLUENT SHORTWAVE TROUGH. SUPERCELLULAR NATURE OF
UPDRAFTS MAY LENGTHEN STORM LIFETIMES AND ENHANCE THREAT FOR
HAIL/WIND AND PERHAPS AN ISOLATED TORNADO.

County outline area:

SEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 486
NWS STORM PREDICTION CENTER NORMAN OK
500 PM EDT WED JUL 4 2007

SEVERE THUNDERSTORM WATCH 486 IS IN EFFECT UNTIL 1000 PM EDT
FOR THE FOLLOWING LOCATIONS

VIRGINIA COUNTIES INCLUDED ARE

ALBEMARLE ALLEGHANY AMELIA
AMHERST APPOMATTOX BATH
BEDFORD BLAND BOTETOURT
BUCKINGHAM CAMPBELL CARROLL
CHARLOTTE CRAIG CUMBERLAND
FLOYD FLUVANNA FRANKLIN
GILES GOOCHLAND GRAYSON
HALIFAX HENRY LOUISA
LUNENBURG MECKLENBURG MONTGOMERY
NELSON NOTTOWAY ORANGE
PATRICK PITTSYLVANIA POWHATAN
PRINCE EDWARD PULASKI ROANOKE
ROCKBRIDGE SMYTH SPOTSYLVANIA
TAZEWELL WYTHE

VIRGINIA INDEPENDENT CITIES INCLUDED ARE

BEDFORD BUENA VISTA CHARLOTTESVILLE
COVINGTON DANVILLE GALAX
LEXINGTON LYNCHBURG MARTINSVILLE
RADFORD ROANOKE SALEM

As we discussed earlier conditions have become unstable across the Eastern U.S. and two tornado watches have now been issued. The most recent is near Nelson, but does not include us at this time. I would not be surprised to see the watch area expanded later this evening. Dewpoints are running in the low 70’s so the air is very moist at this time. Again, Nelson is not included in this watch, but is very close to the watch area.

URGENT – IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 483…CORRECTED
NWS STORM PREDICTION CENTER NORMAN OK
205 PM EDT WED JUL 4 2007

CORRECTED TO “MUCH OF MARYLAND” INSTEAD OF “MARYLAND”

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

DISTRICT OF COLUMBIA
MUCH OF DELAWARE
MUCH OF MARYLAND
MUCH OF NEW JERSEY
SOUTHERN AND EASTERN PENNSYLVANIA
NORTHERN AND CENTRAL VIRGINIA
EASTERN WEST VIRGINIA
COASTAL WATERS

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 205 PM UNTIL
1000 PM EDT.

TORNADOES…HAIL TO 1 INCH IN DIAMETER…THUNDERSTORM WIND GUSTS
TO 70 MPH…AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 65 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 5 MILES SOUTH SOUTHEAST OF
TRENTON NEW JERSEY TO 80 MILES WEST SOUTHWEST OF MARTINSBURG WEST
VIRGINIA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).

REMEMBER…A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

OTHER WATCH INFORMATION…CONTINUE…WW 482…

DISCUSSION…TSTMS/POSSIBLE SUPERCELLS EXPECTED TO INCREASE OVER WW
THIS AFTERNOON THROUGH THE EVENING AS HEATING CONTINUES IN
MODERATELY SHEARED /40 KT/ ENVIRONMENT INVOF NW FLOW SHORT WAVE
TROUGH. WHILE INSTABILITY WILL REMAIN FAIRLY LIMITED…SUBSTANTIAL
DIRECTIONAL COMPONENT TO DEEP SHEAR WILL FAVOR A SEMI-DISCRETE MODE
WITH STORMS THAT DO FORM. DECREASING LCLS AND STRENGTHENING LLJ
INVOF WARM FRONT OVER ERN PA MAY ENHANCE POTENTIAL FOR LOW LVL STORM
ROTATION INTO EARLY EVENING EWD INTO NJ.

The atmosphere over Central Virginia is becoming a bit unstable. The storm prediction center is watching area that may require a severe thunderstorm watch later today just to our NE. That is where the bulk of the severe weather should be. We have chances again Thursday. A tornado watch is already in effect to our west in WV

MESOSCALE DISCUSSION 1380
NWS STORM PREDICTION CENTER NORMAN OK
1139 AM CDT WED JUL 04 2007

AREAS AFFECTED…DELMARVA REGION

CONCERNING…SEVERE POTENTIAL…WATCH POSSIBLE

VALID 041639Z – 041745Z

THUNDERSTORMS ARE EXPECTED TO DEVELOP SHORTLY OVER THE HIGHER
TERRAIN OF THE CENTRAL APPALACHIANS…AND THEN INTENSIFY AS THEY
MOVE EWD INTO THE DELMARVA REGION DURING THE MID/LATE AFTERNOON
HOURS. A WW MAY BE NEEDED LATER THIS AFTERNOON.

WV IMAGERY AND MORNING ANALYSIS INDICATES A SHORTWAVE TROUGH IS
CURRENTLY MOVING EWD THROUGH WRN PA AND WV. LARGE SCALE LIFT
ASSOCIATED WITH THESE SYSTEMS SHOULD AID THUNDERSTORM DEVELOPMENT
OVER THE LESS CAPPED HIGHER TERRAIN SHORTLY…WITH STORMS SHIFTING
EWD INTO DELMARVA BY MID/LATE AFTERNOON. ALTHOUGH INSTABILITY WILL
NOT BE PARTICULARLY STRONG…MLCAPES AROUND 1000 J/KG AND
INCREASING DEEP LAYER SHEAR…ASSOCIATED WITH A 50 KT MID LEVEL JET
MAX MOVING THROUGH PA…ARE EXPECTED TO BE FAVORABLE FOR SEVERE
STORMS. ALTHOUGH TORNADOES WILL BE POSSIBLE GIVEN THE STRONG
DIRECTIONAL SHEAR IN LOWER 1-2 KM…THE STRENGTHENING WLY WINDS
ABOVE THE BOUNDARY LAYER SUGGESTS THAT WIND DAMAGE SHOULD BE THE
MAIN THREAT.