Area Forecast Discussion
Issued by NWS Sterling, VA
FXUS61 KLWX 142002
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
302 PM EST Tue Feb 14 2017
A disturbance will move offshore later this afternoon as a brief
area of high pressure noses into the region. This high will be
short-lived as a low pressure system over the northern Great
Lakes swings a strong cold front southeastward Wednesday. This
front will bring colder air and gusty winds Wednesday into
Wednesday evening. A southern disturbance will bring a chance
for rain across parts of southern Maryland Wednesday into
.NEAR TERM /THROUGH WEDNESDAY/...
Clouds are breaking and dissipating from northwest to southeast
across the region as a disturbance moves east and offshore later
this afternoon. Temperatures have been struggling to climb into
the middle 40s during this afternoon due to the cloud cover. Partial
clearing skies tonight before clouds move back into the region
with an approaching cold front. Temperatures will gradually fall
into the middle 30s tonight. A chance for a little light rain
or snow in the Appalachian Mountains and just to the east
overnight, while some light rain will look to move into southern
Maryland and eastern Virginia from the south as a series of
upper level disturbances ride along the southern branch of the
jet stream. The best chance will be before daybreak Wednesday
throughout Wednesday morning. High temperatures will rise to
about where they were today...in the middle 40s. Colder air and
strong gusty northwest winds will follow the strong cold front
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
As the main upper level trough of low pressure pivots to the
east of our region Wednesday night, gusty northwest winds will
usher in drier air to help alleviate us from any rain showers to
the south and mix of rain and snow showers to the west. Some
upslope snow showers will develop on the backside of the upper
level trough due to a gusty west-northwest to northwest flow.
Accumulations at this time are expected to be light in most
locations. As for Thursday into Thursday night, northwest winds
should gradually diminish, as well as the upslope snow showers.
There could be a few locations across the Central Appalachian
that receive a small accumulation. Dry conditions elsewhere to
the east of the Appalachian Front with temperatures about 10 to
15 degrees colder Thursday and Thursday night than Wednesday
and Wednesday night.
.LONG TERM /FRIDAY THROUGH TUESDAY/...
Quiet weather in the long term forecast starting Friday as
high pressure is centered to our south. Northwesterly flow will
become southwesterly as high pressure moves off the southeast
coast Friday night into Saturday, increasing the weekend
temperatures in the 50s and 60s.
An upper level disturbance could increase PoPs for Saturday night
into Sunday morning as it moves to our south... but seeing mainly
dry conditions over our CWA, and little impact to temperatures. High
pressure builds back after this disturbance returning the dry
weather late Sunday into Tuesday with high temperatures in the 50s
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
Vfr conditions this afternoon through Thursday. Winds this
afternoon southwest 5 to 10 knots. Winds becoming west-northwest
15 to 20 knots gusts 25 knots Wednesday night through Thursday.
Dry conditions expected Friday into Saturday, with
maybe some showers Saturday night into early Sunday as an upper
level disturbance moves near by. Dry conditions return Sunday into
Monday. VFR conditions expected during this period.
A marine weather statement is in effect through mid-afternoon
for gusty south to southwest winds. No marine hazards expected
late this afternoon and tonight. Small craft advisories are in
effect Wednesday through Thursday for gusty northwest winds. A
gale warning may be needed for portions of the waters Wednesday
night into Thursday.
Dry conditions expected Friday into Saturday, with maybe some
showers Saturday night into early Sunday as an upper level
disturbance moves near by. Dry conditions return Sunday into
Monday. Winds expected to remain below the small craft advisory
threshold, so not anticipating an advisory during this period at
MARINE...Small Craft Advisory from 9 AM to 6 PM EST Wednesday for