Area Forecast Discussion
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FXUS61 KLWX 161508
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1108 AM EDT Sat Jul 16 2016
A surface trough will remain overhead through the weekend. The
boundary will dissipate Monday before a cold front moves into the
area Monday night into Tuesday. The boundary will stall just
to the south during the middle portion of next week.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Weak remnant of a frontal boundary settles near the area and
stalls out this afternoon. This combined with an impulse of
energy aloft will be enough to trigger some scattered showers and
thunderstorms this afternoon. While not expecting much in the way
of a widespread severe threat, could see an isolated stronger
storm or two with the development of 1000-1500 J/KG of MLCAPE and
around 30 knots of 0-6KM shear. It should be noted that if
convection can build tall enough, there is significantly more
shear available above 6KM AGL.
Another very warm near-seasonal summer day expected with highs in
the mid 80s to around 90F.
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
Convection ongoing this evening will weaken and dissipate heading
into tonight. Also expecting gradual clearing, which may lead to
the development of some patchy fog, especially in areas that see
rain this afternoon/evening. Lows 60s to mid 70s.
Sunday will be the best day of the weekend with mostly sunny skies
as high pressure moves in overhead. Temperatures similar to today,
but likely a degree or two warmer, mid 80s to low 90s.
Temperatures increase further Monday, the hottest of the next
several days, out ahead of an approaching frontal system. Highs
expected to reach the low to mid 90s, but with higher dew point
values slow to return, should not be overly oppressive, with heat
indices currently forecast to remain below 100F. Some showers and
thunderstorms may approach from the northwest late in the day.
Cold front moves towards the region for Monday night. Mid level
lapse rates increase, and some MLCAPE modeled to remain over the
region, so will have to watch to see if some of the
showers/thunderstorms likely ongoing Monday evening upstream over
the Ohio Valley can make it into the region Monday night.
.LONG TERM /TUESDAY THROUGH FRIDAY/...
A cold front will will pass through the area Tuesday into Tuesday
night and it will stall out just to the south Wednesday and
Thursday. Showers and thunderstorms are possible...especially
along and ahead of the boundary Tuesday. The best chance for
thunderstorms will be across central Virginia into southern
Maryland where heat and humidity will be a bit higher.
Weak high pressure will build in the area behind the front for
Wednesday and Thursday. Seasonably hot conditions are expected
during this time...but humidity will be a bit lower. The high will
shift offshore and weaken late in the week while a cold front
moves through the central Conus. A southwest flow will likely
allow for the return of more hot and humid conditions for Friday
and Saturday. Much of the time should turn out dry for Wednesday
and Thursday due to lower humidity...but also for Friday and
Saturday too due to a westerly component to the low-level wind
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
Generally VFR through the TAF period. Mostly clear skies expected
for the remainder of the early morning hours. Some patchy fog
possible at CHO for a few hours, so have maintained some MVFR in
Scattered showers and thunderstorms expected to develop this
afternoon, so have shown a VCTS. Activity too scattered to
warrant TSRA yet.
VFR Sunday aside from any patchy early fog potential. VFR
conditions expected to prevail through much of Monday.
The next chance for some showers/thunderstorms will be late
VFR conditions are expected most of Tuesday through Wednesday. A
couple showers and thunderstorms are possible Tuesday...with the
best chance toward KCHO.
Winds are 18 knots this morning, but may again briefly approach
criteria later this afternoon and evening. Will leave gusts below
18 knots for now. Risk of gusty thunderstorms later this afternoon
and evening as well, with potential for Marine Weather
Statements/Special Marine Warnings.
Sunday expected to be tranquil with sub-SCA winds, but southerly
channeling ahead of next front will bring potential for SCA winds
Sunday night, and more likely late Monday/Monday night.
A cold front will pass through the area Tuesday into Tuesday
night. A few showers and thunderstorms are possible. The best
chance for thunderstorms will be across the lower Tidal Potomac
River and middle portions of the Bay. Any thunderstorms that do
develop may contain gusty winds. High pressure will settle
overhead for Wednesday and Thursday. A pressure surge behind the
cold front may cause gusts around SCA criteria Tuesday night.