Area Forecast Discussion
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FXUS61 KLWX 270037
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
837 PM EDT Fri Aug 26 2016
A dry cold front will move through the area this
evening. High pressure will build tonight through early Sunday.
Another cold front will move through the area middle of next week.
.NEAR TERM /THROUGH SATURDAY/...
A weak boundary over the area this evening currently extends
across northern Virginia into southern Maryland. There is a
dewpoint gradient along the boundary...and a couple showers and
thunderstorms develop to the south of this boundary across central
Virginia. This activity should dissipate this evening due to the
loss of daytime heating.
The boundary will slowly shift south tonight and a ridge of high
pressure both at the surface and aloft will build over the area
Mainly clear skies and light winds will cause patchy fog in
sheltered valleys and rural areas...but widespread fog is not
expected at this time. Plenty of sunshine is expected Saturday and
unseasonably hot conditions will continue...but not quite as hot
as Friday with max temps forecast to be in the upper 80s to lower
90s across most locations.
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
Surface high pressure will shift to the coast Saturday night and
a light easterly flow is expected. This may lead to low clouds
toward morning across eastern portions of the CWA. For locations
west of the Blue Ridge Mountains...mainly clear skies are expected
with patchy fog. Latest GFS suggests some increase in moisture
with some light showers over the mtns Sun as easterly flow
continues. Think this is largely overdone given vertically
stacked high pressure center over the area resulting in strong
subsidence. Will downplay precip potential. Hot again with temps
in the low 90s.
.LONG TERM /MONDAY THROUGH FRIDAY/...
Ridge of high pressure will begin to weaken Mon with a
dissipating front to the north and west. The weakening ridge and
increasing warmth and instability may result in isolated showers
and t-storms over the mtns. Heights will fall more sharply Tue and
Wed as a pair of nrn stream disturbances move across. The stronger
of these will help push a cdfnt through the area Wed night
bringing better precip potential to the area Wed afternoon. Trough
pushes east Thu with high pressure building again Thu through the
Labor Day weekend. Hotter and more humid Mon through Wed with
temps in the mid 90s and heat indices above 100F. Much cooler Thu
and Fri behind front with temps in the mid 80s.
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
Patchy fog may develop overnight into early Saturday. MVFR vsbys
are possible across KMRB and KCHO during this time. Easterly flow
may impact the terminals late Saturday night through Sunday night.
Areas of low clouds and fog are possible during the late night and
early morning hours each day. Precip chances increase Tue and Wed
with showers/t-storms possible especially Wed.
Winds increase somewhat Sat and Sun afternoons, but
will likely remain below SCA criteria. T-storms possible Wed
afternoon with a frontal passage.
High temperature tied the old record of 95 degrees at Washington
Dulles Airport today. The old record of 95 occurred in
1998...1993 and 1975.
Ranking of summer 2016 in terms of average temperature (JUN 1 - AUG 25)
Site RankAverage Temperature
DC 3 (tie with 2012)80.4
Balt 19 (tie with 2 other years) 77.2
IAD 3 77.2