Dense Fog in Virginia, June 4, 2016

Area Forecast Discussion...UPDATED
National Weather Service Baltimore MD/Washington DC
941 PM EDT FRI JUN 3 2016

.SYNOPSIS...
A strong cold front will approach the region Sunday before
passing through Sunday night. An upper level trough will build
overhead Monday through Wednesday before surface high pressure
builds into the region Wednesday night and Thursday.

&&

.NEAR TERM /THROUGH SATURDAY/...
High moisture content...wet ground and onshore flow will lead to
low clouds and fog overnight. Already seeing low ceilings and fog
developed in northeast MD and Fort Belvoir respectively. Expect
most areas east of the Blue Ridge to be in low cloud overcast
and/or fog late tonight into early Sat. Lone shower over
Shenandoah should dissipate soon.

&&

.SHORT TERM /SATURDAY NIGHT/...
Moisture and instability build further on Saturday with showers
and thunderstorms likely west of the Blue Ridge moving east into
the metros in the evening. T-storms could produce torrential
downpours which may cause flash flooding of small streams and
creeks.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Sunday is still looking like the most high-impact day of the
weekend, although there are considerable nuances as to how the day
will unfold. Deepening surface low pressure will be lifting out of
the Great Lakes with the attendant cold front trailing to the
southwest. Mid/upper level trough will be taking on a negative tilt,
with Mid-Atlantic situated on the divergent side of an upper level
jet streak. Low-level flow will also be increasing, with 40 kt at 850
mb by Sunday evening. These strong dynamics are expected to overcome
modest lapse rates and considerable cloud cover to produce
widespread showers and thunderstorms. Nevertheless, the severity of
late afternoon/evening thunderstorms (when best height falls and
deep layer shear are expected), will likely depend on the amount of
early-day convection/showers, and if any insolation can be realized.
Would think highest risk would be with damaging wind gusts, followed
by hail depending on the amount of instability. The tornado threat
is non-zero, but the 0-1 km portion of the hodograph isn't terribly
favorable. In addition, with PWATs likely above 1.75 inches and the
potential for multiple rounds of convection, heavy rain and flash
flooding will also be possible.

The cold front will push east Sunday night, with most of the
thunderstorms pushing east of the area by midnight. The chance for
showers will linger a little longer in the upslope region of the
Appalachians. Highs Sunday will likely be able to push into the 80s
despite cloud cover, followed by lows in the 60s Sunday night.

A large upper-level low, the impetus for the Sunday cold front,
will spiral slowly to the north of the area through much of next
week. Deep-layer westerly flow will prevail which usually leads to
a drier pattern. This should also help push low pressure moving up
from the Gulf of Mexico out to sea well south of the area.
However, shortwaves and accompanying surface frontal boundaries
rotating around the upper low could turn the low-level flow
southerly briefly increasing moisture Tuesday and again late in
the week. There is uncertainty to the extent of the moisture, but
mid-level temperatures will be quite cool for early June which
could lend to an unstable atmosphere and aid in the development of
showers or a few thunderstorms. After a somewhat cooler week, a
substantial warming trend should begin next weekend.

&&

.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
Low cigs and fog seem likely overnight. Tafs have IFR and LIFR
conditions in the fcst.

Showers and isolated thunderstorms may be ongoing Sunday morning,
and any light fog/sub-VFR clouds that develop could take until mid
morning to lift. The best chance for severe thunderstorms will be
from mid afternoon to early evening, with potential for strong wind
gusts, hail, and heavy rain with IFR conditions. A cold front will
push east Sunday night, ending the threat of storms.

VFR expected Monday into Monday night with westerly winds
of 10 to 15 knots. A secondary cold front will approach Tuesday and
may spark off a couple of showers or a thunderstorm. This should
also turn winds more southerly Tuesday at around 10 knots.

&&

.MARINE...
No problems foreseen on the waters through Saturday night outside
of possible thunderstorms.

A strong cold front will approach on Sunday, before passing through
Sunday night. A Small Craft Advisory may be needed. There will also
be potential for strong to severe thunderstorms during the afternoon
and evening hours, with potential for hail and wind gusts above 34
kt, and isolated gusts to 50 kt.

Small Craft Advisories may be needed Monday into Tuesday for
gusty westerly winds in the wake of Sunday's strong cold front.
Winds may briefly channel out of the south ahead of a secondary cold
front Tuesday afternoon.

&&

.TIDES/COASTAL FLOODING...
Minor coastal flooding expected at Annapolis and North Beach
overnight into early Sat. Coastal flood advisory issued.

The light onshore flow will continue through Saturday night
before turning toward the south and increasing a bit for Sunday.
This, combined with new moon, will continue to cause elevated
water levels. Minor flooding cannot be ruled out for sensitive
areas during the high tide cycle early Sunday.

Westerly winds will develop behind the cold front Sunday night.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Coastal Flood Advisory from 2 AM to 8 AM EDT Saturday for
     MDZ014-018.
VA...None.
WV...None.
MARINE...None.

&&

SYNOPSIS...LFR
NEAR TERM...LFR
SHORT TERM...LFR
LONG TERM...DFH
AVIATION...LFR/DFH
MARINE...LFR/DFH
TIDES/COASTAL FLOODING...lfr

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
805 PM EDT FRI JUN 3 2016

ANZ530>543-DCZ001-MDZ011-013-014-016>018-508-VAZ052>057-040930-
CHESAPEAKE BAY NORTH OF POOLES ISLAND MD-
CHESAPEAKE BAY FROM POOLES ISLAND TO SANDY POINT MD-
CHESAPEAKE BAY FROM SANDY POINT TO NORTH BEACH MD-
CHESAPEAKE BAY FROM NORTH BEACH TO DRUM POINT MD-
CHESAPEAKE BAY FROM DRUM POINT MD TO SMITH POINT VA-
TIDAL POTOMAC FROM KEY BRIDGE TO INDIAN HEAD MD-
TIDAL POTOMAC FROM INDIAN HEAD TO COBB ISLAND MD-
TIDAL POTOMAC FROM COBB ISLAND MD TO SMITH POINT VA-
PATAPSCO RIVER INCLUDING BALTIMORE HARBOR-
CHESTER RIVER TO QUEENSTOWN MD-EASTERN BAY-
CHOPTANK RIVER TO CAMBRIDGE MD AND THE LITTLE CHOPTANK RIVER-
PATUXENT RIVER TO BROOMES ISLAND MD-
TANGIER SOUND AND THE INLAND WATERS SURROUNDING BLOODSWORTH
ISLAND-DISTRICT OF COLUMBIA-SOUTHERN BALTIMORE-PRINCE GEORGES-
ANNE ARUNDEL-CHARLES-ST. MARYS-CALVERT-SOUTHEAST HARFORD-
PRINCE WILLIAM/MANASSAS/MANASSAS PARK-FAIRFAX-
ARLINGTON/FALLS CHURCH/ALEXANDRIA-STAFFORD-SPOTSYLVANIA-
KING GEORGE-
805 PM EDT FRI JUN 3 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE MARYLAND PORTION OF THE
CHESAPEAKE BAY...TIDAL POTOMAC RIVER...AND ADJACENT COUNTIES IN
CENTRAL MARYLAND AND NORTHERN VIRGINIA AS WELL AS THE DISTRICT OF
COLUMBIA.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

SHOWERS AND THUNDERSTORMS ARE EXPECTED SUNDAY. SOME THUNDERSTORMS
MAY BECOME SEVERE AND PRODUCE DAMAGING WINDS...A FEW TORNADOES AND
HEAVY RAINFALL. TORRENTIAL DOWNPOURS SUNDAY MAY LEAD TO LOCALIZED
FLASH FLOODING OF SMALL STREAMS AND CREEKS AS WELL AS URBAN AREAS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED SUNDAY.

MDZ003>006-501>507-VAZ025>031-036>040-050-051-501>508-WVZ050>053-
055-501>506-040930-
WASHINGTON-FREDERICK MD-CARROLL-NORTHERN BALTIMORE-
EXTREME WESTERN ALLEGANY-CENTRAL AND EASTERN ALLEGANY-
NORTHWEST MONTGOMERY-CENTRAL AND SOUTHEAST MONTGOMERY-
NORTHWEST HOWARD-CENTRAL AND SOUTHEAST HOWARD-NORTHWEST HARFORD-
AUGUSTA-ROCKINGHAM-SHENANDOAH-FREDERICK VA-PAGE-WARREN-CLARKE-
NELSON-ALBEMARLE-GREENE-MADISON-RAPPAHANNOCK-ORANGE-CULPEPER-
NORTHERN FAUQUIER-SOUTHERN FAUQUIER-WESTERN HIGHLAND-
EASTERN HIGHLAND-WESTERN LOUDOUN-EASTERN LOUDOUN-
NORTHERN VIRGINIA BLUE RIDGE-CENTRAL VIRGINIA BLUE RIDGE-
HAMPSHIRE-MORGAN-BERKELEY-JEFFERSON-HARDY-WESTERN GRANT-
EASTERN GRANT-WESTERN MINERAL-EASTERN MINERAL-WESTERN PENDLETON-
EASTERN PENDLETON-
805 PM EDT FRI JUN 3 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN WEST VIRGINIA...
NORTHERN AND CENTRAL VIRGINIA...AND CENTRAL AND WESTERN MARYLAND
WITH THE EXCEPTION OF GARRETT COUNTY.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

SHOWERS AND THUNDERSTORMS ARE EXPECTED SUNDAY. SOME THUNDERSTORMS
MAY BECOME SEVERE AND PRODUCE DAMAGING WINDS...A FEW TORNADOES AND
HEAVY RAINFALL. TORRENTIAL DOWNPOURS SUNDAY MAY LEAD TO LOCALIZED
FLASH FLOODING OF SMALL STREAMS AND CREEKS AS WELL AS URBAN AREAS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED SUNDAY.