Area Forecast Discussion
Issued by NWS Sterling, VA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
FXUS61 KLWX 261358

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
958 AM EDT Wed Oct 26 2016

High pressure will remain over the region through tonight. A cold
front will cross the area Thursday afternoon and evening. High
pressure returns Friday and Friday night. A secondary cold front
crosses the area this weekend with high pressure then into at
least the middle of next week.


First freeze for IAD and BWI - please see climate section below.

As of 9am, a 1038mb surface high is over northern Ontario with a
surface ridge extending south to the central Mid-Atlantic. A
1013mb surface high is over IA with a warm front extending east to
Cleveland. This warm front will extend east across PA through this
evening and the low crosses the eastern Great Lakes through

The surface high pressure ridge drifts east today and a weak
onshore flow beginning this afternoon. Max temps in the 50s and
40s in the mountains are expected. A warm front will move
northward across the Ohio Valley region this afternoon and
evening. High pressure in place across the Mid-Atlantic will keep
the warm front from moving northward across the region, however,
mid-high clouds will increase from west to east today and tonight
in response to the warm front aloft. As moisture advects
northward, showers are also possible, however, they should stay
west and north of the Mid- Atlantic region as the associated low
pressure system moves into the Great Lakes region by Thursday


Low pressure will move across Lake Erie and Lake Ontario Thursday
while a cold front approaches the Mid-Atlantic region. The warm
front will move through the region by Thursday afternoon. Clouds
and showers are expected, however, the greatest forcing will be
associated with the sfc low to our north. Rainfall amounts should
not exceed a half inch into Thursday night. Winds will also
increase ahead of the cold front Thursday afternoon and then
behind the front Thursday evening. Winds at higher elevations will
also be greater and gusts up to 35-40 mph will be possible during
this time.

The cold front moves to the east by Friday morning. Dry conditions
are expected with the exception of showers tapering off across the
Allegheny Front. High pressure will move overhead by Friday
evening, however, it should quickly move east of the region by
Saturday morning.


Heights will be rising on Sat with H85 temps climbing to 13C
close to the 90% percentile for late Oct. This will support warm
temperatures well into the 70s and close to 80F in
Charlottesville. Will need to watch Rh`s closely on Sat for an
enhanced fire weather threat in case dewpoints do not recover as
models suggest. A shortwave-trough and associated cdfnt cross the
area Sun afternoon. A few showers appear possible along the Mason-
Dixon line Sun morning. Temperatures could actually turn out to be
warmer on Sun especially south of the Potomac River due to
downslope flow. A brief cool down expected on Mon but temps
expected to rebound again for the middle part of next week as
ridge of high pressure amplifies over the southeast U.S. into the
mid-Atlantic. Temperatures likely to rise well into the 70s and
possibly low 80s middle of next week.


VFR conditions are expected through tonight. Clouds will increase
from west to east this afternoon. A cold front will approach the
region Thursday and showers are possible. Cigs will lower with
these showers and MVFR conditions are possible at this time. Winds
will increase Thursday as well and gusts up to 20-30kts are
possible in the afternoon and evening. VFR conditions are expected
Friday-Friday night.

VFR conditions expected Sat and Sun.


NE winds around 10kts expected on the waters today and tonight.
Southerly winds will increase ahead of a cold front Thursday. The
cold front will pass through Thursday evening and gusty northwest
winds are expected behind the front overnight Thursday. A Small
Craft Advisory is in effect Thursday through Thursday night.
Winds may approach gale conditions mainly across the main channel
of the Bay Thursday/Thursday night however confidence is low if a
gale warning will be needed. Showers associated with the cold
front will be gusty and may require special marine warnings,
particularly Thursday evening.

NW winds will continue Friday and SCA conditions are expected
during this time. Winds should diminish Friday night.

Small craft conditions are possible Sat afternoon and Sat night.


Baltimore-Washington International Thurgood Marshall Airport
(BWI) near Baltimore MD dropped to 32 degrees this morning,
marking the first time since April 10th that the temperature has
dropped to freezing (low on April 10 was 26 degrees).

Washington Dulles International Airport (IAD) in northern Virginia
dropped to 30 degrees, which is the first time the temperature has
fallen below freezing there since April 14th (when the low was
31 degrees).

Ronald Reagan National Airport near Washington DC (DCA) was 41
degrees this morning. Its last day at or below freezing was 31
degrees on April 10.


MARINE...Small Craft Advisory from 10 AM Thursday to 6 AM EDT Friday
     for ANZ530>532-535-536-538>542.
     Small Craft Advisory from 7 AM Thursday to 6 AM EDT Friday for


CLIMATE...DFH is the U.S. government's official web portal to all federal, state and local government web resources and services.