TM () > WX — Thursday, September 19, 2019
DC Climate ReportDCwxWeatherSunrise: 6:53; Solar Noon: 1:02; Sunset: 7:11

Last 72 Hours: ObservationsCurrently: 75°F  — USNO Clear Sky Chart

Coastal Flood Advisory

Today: Sunny, with a high near 73°. Calm wind becoming northeast 5 to 8 mph in the morning.

Tonight: Clear, with a low around 54°. Southeast wind around 6 mph becoming calm after midnight.

Friday: Sunny, with a high near 80°. Southwest wind 3 to 6 mph.

Friday Night: Clear, with a low around 60°. Southwest wind around 5 mph becoming calm in the evening.

Saturday: Sunny, with a high near 87°. Light west wind.

Saturday Night: Mostly clear, with a low around 63°.

Sunday: Sunny, with a high near 91°.

Sunday Night: Mostly clear, with a low around 68°.

Monday: Mostly sunny, with a high near 88°.

Monday Night: A chance of showers after 9pm. Mostly cloudy, with a low around 66°. Chance of precipitation is 30%.

Tuesday: A chance of showers. Mostly sunny, with a high near 82°. Chance of precipitation is 30%.

Tuesday Night: Mostly clear, with a low around 62°.

Wednesday: Mostly sunny, with a high near 82°.

Latest Forecast | Forecast Archive | Observations Archive

ISS Sightings over Washington, D.C.

FXUS61 KLWX 190120

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
920 PM EDT Wed Sep 18 2019

High pressure will remain in place over the region through this
weekend. The high that was sitting over our region will sink
southeasterly out of our region as a weak cold front approaches from
the northwest.


High pressure will remain overhead for tonight, bringing dry and
cool conditions. Light winds and mainly clear skies will allow
for radiational cooling. Min temps will range from the 40s in
the colder valleys and rural areas, to the 50s across most other
locations. Patchy fog is expected in the sheltered valleys,
especially over the Potomac Highlands and some of that may be
locally dense. However, with lower dewpoints widespread fog is
not expected.


A strong upper level ridge will remain in place over the eastern
half of the United States through Friday evening. High pressure will
be in place over our region during this period. Dry conditions along
with mostly clear to partly cloudy conditions expected during this
period. Winds will begin out of the northeast to east on Thursday
and slowly become southerly by Friday. Daytime temperatures will
continue to be mild in the 70s with overnight temps in the 40s and
the low 50s. Temps will trend upwards into the upper 70s to low 80s
on Friday with more mild overnight temps in the mid 50s to low


Mid-upper level ridge will be in control through Sunday
leading to hot and dry weather. The ridge pattern starts
breaking down Sunday night as a trof extending from James Bay
to the eastern Great Lks swings through the Northeast U.S.
An associated cold front will cross the area late Monday night
or Tue morning. This front will lack deep moisture, frontal
convergence, and will be passing through during an unfavorable
time of day to support widespread convection. Expect only few-
sct showers Mon night with only light precip amounts expected as
the front moves through. The trof axis will cross the area on
Tue with upper level convergence and surface high pressure
building on its wake leading to continued above normal
temperatures and mainly dry conditions.


High pressure will remain over the region through Friday.
VFR conditions are expected for most of the time, but a period
of MVFR cigs/vsbys are possible near KCHO overnight into
Thursday morning, and again Thursday night into Friday morning.

VFR conditions expected with no significant weather this weekend
through Monday.


Small craft advisories are in effect for the Tidal Potomac and the
central Chesapeake Bay this evening through the tomorrow morning. No
marine hazards expected Thursday through Friday night at this

Possible SCA conditions Monday in westerly flow ahead of a


A persistent onshore flow has caused anomalies to increase, and
the onshore flow is expected to continue through Thursday before
dissipating Thursday night and turning slightly offshore Friday.

Anomalies to the south are a touch higher than to the north, and
with lighter winds in place these anomalies should creep up.
Therefore, minor flooding is expected with the tide cycle
Thursday morning for Anne Arundel, Calvert, St Marys, and
Washington DC/Alexandria. It will be very close for Calvert
County (Solomons Island) and Alexandria, but with the higher
anomalies south, we decided to lean a little more pessimistic
with forecast values just above minor flooding thresholds.

For Baltimore northward, water levels will be very close to
minor flooding thresholds late this evening and overnight, but
confidence is too low for an advisory at this time. The high
tide cycle Thursday morning/early afternoon will be the lower of
the two, so confidence is not as high for minor flooding.
Therefore, and advisory has not been issued at this time.

The high tide cycle later Thursday afternoon into Thursday night
is likely to cause minor flooding for most areas. Moderate
flooding is not expected at this time since the flow will be
weakening a bit.


DC...Coastal Flood Advisory until 3 PM EDT Thursday for DCZ001.
MD...Coastal Flood Advisory from 3 AM to 10 AM EDT Thursday for
Coastal Flood Advisory until 11 AM EDT Thursday for MDZ014.
Coastal Flood Advisory until 9 AM EDT Thursday for MDZ017.
Coastal Flood Advisory until 10 AM EDT Thursday for MDZ016.
VA...Coastal Flood Advisory until 10 AM EDT Thursday for VAZ057.
Coastal Flood Advisory until 3 PM EDT Thursday for VAZ054.



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