Area Forecast Discussion
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FXUS61 KLWX 260126 AAA
Area Forecast Discussion...UPDATED
National Weather Service Baltimore MD/Washington DC
926 PM EDT Tue Apr 25 2017
Low pressure off of the Delmarva will move slowly northeastward
away from the Mid-Atlantic coast Wednesday. A cold front will
approach the region Thursday night and dissipate on Friday. A
cold front will pass through the region early next week.
.NEAR TERM /THROUGH WEDNESDAY/...
Light rain will continue overnight along the western shore of
the Chesapeake Bay along inverted trof north of weakening sfc
low. West of the Blue Ridge, increasing mid-level subsidence
overnight will lead to areas of dense fog.
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
Coastal low pressure will be off the Ocean City MD coast
Wednesday morning. Rain will still be around the region in the
morning as wrap- around moisture moves around the storm system.
Winds will become NW Wednesday however dry air will take time
to move into the region. Clouds will diminish from west to east
throughout the day. Temps will climb to near 70 Wednesday.
Ridging is expected across the region Wed night and dry
conditions are expected. Low-level moisture is expected Wed
night and fog is likely into Thursday morning. Southerly flow
increases Thursday and temps rebound into the 80s by afternoon.
A cold front will cross the region Thursday night. Showers and a
few rumbles of thunder are possible.
.LONG TERM /FRIDAY THROUGH TUESDAY/...
A cold front should slide across our region Friday before stalling
across central or eastern portions of Virginia later in the day then
inching northward as a weak warm front Friday night. There is a
slight chance of a shower or thunderstorm during the period with
high temperatures remaining on the warm side.
On Saturday, high pressure will be to our southeast with a front now
along the Mason-Dixon line. Temperatures will remain warm with a
slight chance of a shower or thunderstorm mainly across the northern
half of our region.
By Sunday into Sunday night, the high to the southeast will break
down with the front meandering across the northern half of our
region. The chance for showers and thunderstorms will become more
prominant, mainly Sunday night into Monday due to the ridge breaking
An increasing southerly wind will usher in warmer and more humid air
to help fuel showers and thunderstorms later Monday into Monday
evening. A strong cold front should works its way eastward across
the region Monday night.
Gusty westerly winds and drier and cooler air will filter into the
region Tuesday behind the cold front as high pressure builds in from
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
IFR conditions will continue through tonight as low-level moisture
from low pressure continues to influence the terminals. -RA and DZ
are expected with variable fog which may reduce conditions to LIFR
tonight. Uncertainty exists in the timing of reduced vsbys due to
FG overnight and therefore kept most terminals at 3SM overnight. IFR
conditions continue into Wed morning. Dry air will take time to
bring terminals to VFR Wed so thinking MVFR will likely stick around
for most of the morning. Winds begin as NE this afternoon and will
become NW by Wednesday.
Winds become S Wednesday night into Thursday. BR/FG expected
Wednesday night into Thursday morning and flight restrictions are
Vfr conditions Friday through Saturday. Mvfr conditions in any
isolated shower or thunderstorm. Mvfr to ifr conditions Saturday
night in shower or thunderstorm activity, mainly near MRB, IAD, BWI
and MTN terminals. Winds southwest 5 knots Friday and Friday night.
Winds southwest 5 to 10 knots Saturday and Saturday night.
Winds will continue to diminish this evening with only the upper
Chesapeake Bay seeing SCA winds. These should drop off after
A southerly flow will develop Wednesday and the southerly flow will
strengthen ahead of a cold front Thursday into Thursday night. A
Small Craft Advisory may be needed for portions of the waters
Thursday into Thursday night.
No marine hazards expected Friday through Saturday night. Winds
southwest 5 to 10 knots Friday and Friday night. Winds southwest
around 10 knots Saturday and Saturday night.
The flow should gradually turn northerly tonight into Wednesday
as the low moves away from the area. Water levels should begin
to decrease during this time...though minor coastal flooding
will remain possible through tonights and tomorrow morning tide
cycles at the most sensitive sites.
DC...Coastal Flood Advisory from 5 AM to noon EDT Wednesday for
MD...Coastal Flood Advisory until 6 AM EDT Wednesday for MDZ017.
VA...Coastal Flood Advisory from 5 AM to noon EDT Wednesday for
MARINE...Small Craft Advisory until midnight EDT tonight for ANZ530-531.