AFDLWX AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 621 AM EDT SAT JUL 9 2011 .SYNOPSIS... A COLD FRONT WILL PUSH OFF THE COAST OVERNIGHT. HIGH PRESSURE WILL BUILD IN FROM THE OHIO VALLEY THROUGH THE WEEKEND. A SECOND FRONT WILL PUSH SOUTH ACROSS THE MID ATLANTIC LATE MONDAY INTO TUESDAY...WITH HIGH PRESSURE RETURNING FOR THE SECOND HALF OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATE...CANCELLED NORTHEASTERN PORTION OF THE DENSE FOG ADVISORY...W/ THESE AREAS SEEING OVERALL IMPROVEMENT W/ ONLY PATCHY AREAS OF 1-2SM FOG. THE REST OF THE ADVISORY AREAS /WEST OF THE BLUE RIDGE AND THE LOWER LEE-BLUE RIDGE FOOTHILL AREAS/ REMAINS IN EFFECT THRU 9 AM. PREV DISC... THOUGH THE FRONTAL BOUNDARY IS NO LONGER A MID ATLANTIC RESIDENT...THERE IS VERY LITTLE OVERALL CHANGE IN THE AIRMASS. LOW LEVEL MOISTURE REMAINS HIGH...AIDED BY THE RECENT RAINFALL. ONLY A FEW ISOLATED AREAS OF DENSE FOG...MOST OBS SHOWING A 3-5SM VARIETY OF VSBYS. WILL CONTINUE TO MONITOR IN THE EVENT A WIDESPREAD REGION OF VSBYS DROP TO 1/4SM...WHICH THERE IS THE POTENTIAL. BEHIND THE EXITING UPPER TROF AXIS THOUGH...GUIDANCE SHOWS A WAVE OF 5KT NLY WINDS SLIDING DOWN THE REGION WHICH MAY BE ENOUGH TO MIX-OUT THE THICKER FOG AND KEEP IN AT 3-5SM PATCHES. AFTER SUNRISE...SKIES WILL BE MAINLY CLEAR OUTSIDE OF A FEW PASSING STREAMS OF LEFTOVER MID LEVEL DECKS FROM THE PROXIMITY OF THE FRONTAL BOUNDARY STILL WORKING ITS WAY OFF THE CAROLINA COAST. LOW LEVEL MOISTURE WILL REMAIN FAIRLY INTACT TODAY. DEWPOINTS WILL DROP INTO THE L60S OVER THE HIGHER TERRAIN AND NWRN QUADRANT OF THE CWA BUT THE METRO AREAS WILL STAY IN THE M60S AND U60S ACROSS THE SRN SUBURBS. EVEN W/ TEMPS CLIMBING ONLY INTO THE U80S AND L90S...CONDITIONS WILL AGAIN FEEL LESS THAN COMFORTABLE DURING THE AFTN HRS. A LIGHT NLY BREEZE WILL HELP TO CUT DOWN A BIT ON THE DISCOMFORT. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/... SKIES WILL CLEAR OUT AGAIN OVERNIGHT AND WINDS WILL SWITCH FROM NLY TO SLY OVER THE COURSE THE NIGHT. DEWPOINTS WILL DROP A FEW DEGREES FROM AFTN LEVELS...ALLOWING FOR TEMPS TO DROP A COUPLE MORE DEGREES FOR OVERNIGHT LOWS THAN IN PREV NIGHTS /L-M60S - 70 IN THE METRO AREAS/. && .LONG TERM /SUNDAY THROUGH FRIDAY/... NO CHANGES TO THE LONG TERM PORTION OF THE FORECAST. HIGH PRESSURE CONTINUES OVERHEAD ON SUNDAY...BUT MOVES OFFSHORE EARLY MONDAY. COLD FRONT MOVES THROUGH LATE MONDAY INTO TUESDAY...BRINGING SCATTERED SHOWERS AND THUNDERSTORMS. HIGH PRESSURE RETURNS FOR THE LATTER HALF OF THE WEEK. && .AVIATION /10Z SATURDAY THROUGH WEDNESDAY/... FOG CONCERNS OVERNIGHT. OBS E OF THE BLUE RIDGE MAINLY SHOWING DROPS IN THE VSBYS...WHILE SHENANDOAH VLY OBS HAVE LOW CIGS AS WELL AS LOW VSBYS. THIS WILL CONTINUE OVER THE NEXT FEW HRS TILL JUST AFTER SUNRISE. METRO DC/BALT AREAS SHOULD ONLY SEE A HIGH-END MVFR VSBY DROP...THOUGH AN OUTSIDE CHANCE OF LOWER VSBYS POSSIBLE IF WINDS DROP OFF - A WEAK NLY BREEZE HOWEVER MAY PREVENT THIS. THRU THE REST OF THE MORNING AFT SUNRISE...FOG WILL MIX OUT AND SKIES WILL CLEAR OUT. A FEW PATCHES OF 4-5KFT CU/STRATOCU MAY DEVELOP LATE MRNG-AFTN. A STIFF NLY BREEZE 5-10KT THIS AFTN...DROPPING TO CALM CONDITIONS OVERNIGHT. NO CIG/VSBY RESTRICTIONS ANTICIPATED SUNDAY OR EARLY MONDAY. COLD FRONT MOVES THROUGH THE REGION LATE MONDAY INTO TUESDAY...WITH SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE. HIGH PRESSURE BUILDS IN FOR WEDNESDAY AND REMAINS IN PLACE FOR THE REMAINDER OF THE WEEK. && .MARINE... LIGHT NLY WINDS OVER THE WATERS...ONLY BRIEF 10KT GUSTS OCCASIONALLY. ADD A COUPLE OF KTS FOR THE DAYTIME HRS...THEN A DROP OFF LATER TODAY AS WINDS TURN TOWARD SLY INTO EARLY SUNDAY. NO HEADLINES ANTICIPATED THROUGH THE LONG TERM. HIGH PRESSURE MOVES OFFSHORE BY EARLY MONDAY AS A COLD FRONT APPROACHES FROM THE WEST. COLD FRONT MOVES THROUGH THE WATERS ON TUESDAY...WITH HIGH PRESSURE RETURNING FOR THE SECOND HALF OF THE WEEK. && .EQUIPMENT... PIKESVILLE NWR WENT DOWN LAST NGT DUE TO A LIGHTNING STRIKE ON A COMMERCIAL POWER TRANSFORMER. TECHS ARE WORKING THE ISSUE...AND WILL DO THEIR BEST TO RETURN SERVICE TODAY. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR MDZ501-502. VA...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR VAZ025>027- 029-030-036>038-503-504. WV...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR WVZ050-055- 501>506. MARINE...NONE. && $$ UPDATE...GMS