493
FXUS61 KLWX 010110
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
910 PM EDT Sun Jun 30 2024

.SYNOPSIS...
A cold front will push through this evening. A strong area of
high pressure settles over the area Monday and Tuesday before
drifting offshore the second half of the week. A warm front
nears the region by mid-week yielding a warming trend.

&&

.NEAR TERM /THROUGH MONDAY/...
A cold front extends from far northeastern Maryland, to just
northwest of Washington DC, and southwest into the central
Shenandoah Valley. Ahead of this cold front, clusters of strong
to severe thunderstorms have developed and are moving to the
southeast. Multiple severe thunderstorm warnings and special
marine warnings are in effect for another hour or so. To the
northwest of this front, northwest to north winds have developed
and will continue through the rest of the evening and into the
overnight. The main threat with the severe thunderstorms will be
wind gusts 60 to 80 mph with quarter to golf ball size hail. An
isolated tornado or waterspout can`t be ruled out. Showers and
thunderstorms may not clear far southern Maryland and the
central Chesapeake Bay until around midnight or shortly
thereafter.

Cooler and much drier air will be ushered into our CWA overnight
behind the cold front. Lows will drop back into the mid 50s to
mid 60s, with 40s possible in the higher elevations.

Upper trough axis will pass through Monday as strong (1025 mb) surface
high pressure build in from the Great Lakes. This will result in
gusty northerly winds through the day and very comfortable
conditions for early July standards. Highs will be in the upper
70s to lower 80s with dew points ranging from the upper 40s to
mid 50s.

&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
Dry and cooler conditions continue with diminishing winds Monday
night with the high passing to the north. Lows in the 50s will
be common, but the I-95 corridor likely stays in the 60s.

With the ridge axis progressing to the east Tuesday, it will be
a little milder, and there may be some extra cloud cover at
times. Dew points will remain in the 50s though, resulting in
continued comfortable weather.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Mostly dry conditions are expected Wednesday as high pressure
holds on before scooting further offshore with large disturbance
approaching from the west. Warm, moist air will build in during
the day on Wednesday, allowing a warm up compared to the
previous few days with highs in the upper 80s to low 90s. Winds
will be elevated out of the SSE, gusting to 20 knots at times
during the afternoon. Overnight lows fall into the upper 60s to
low 70s for most areas.

A large area of low pressure center over the central Canadian
provinces will slowly track further east along a secondary low
across the heart of the CONUS. Showers and thunderstorm chances will
continue from July 4th holiday through the early part of the weekend
with renewed PoPs each afternoon and evening. Should the forcing
became more sufficient locally and convective parameters increase,
strong to severe thunderstorms may be possible during the period but
there remains a lot of uncertainty in this. The heat continues
through the remainder of the week with highs in the low to mid 90s
and heat indices reaching triple digits.

&&

.AVIATION /01Z MONDAY THROUGH FRIDAY/...
Strong to severe thunderstorms have cleared MRB, CHO and IAD
terminals. DCA, BWI and MTN will be cleared from showers and
thunderstorms between 0130z and 0230z Monday. Northerly winds
will take precedence overnight into Monday.

VFR conditions will prevail after storms exit. As the ridge of
high pressure pushes off toward the New England coast, winds
shift to east-southeasterly on Tuesday, before becoming
southerly Tuesday night. VFR continues.

VFR conditions are expected Wednesday and Thursday for the
terminals. Showers and thunderstorms return Thursday, especially
further west, so some isolated instances of sub-VFR conditions is
not completely out of the question for the holiday period.

&&

.MARINE...
Special Marine Warnings are in effect over large pieces of the
Chesapeake Bay and Tidal Potomac for another hour or so.
Otherwise, once the cold front moves southeast of the region,
small craft advisories will be the main story into Monday. The
small craft advisories may need to be extended into Monday
evening for portions of the waters. Winds turn more east-
southeasterly on Tuesday with high pressure to the north,
staying below advisory thresholds.

SCAs are expected Wednesday as high pressure exits to the east and
incoming low pressure and associated frontal features approach from
the west. Winds diminish by July 4th but SMWs may be needed Thursday
afternoon for any strong showers or thunderstorms that cross the
waters.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 2 PM EDT Monday for ANZ530-531-535-
     536-538-539.
     Small Craft Advisory until 10 PM EDT this evening for
     ANZ532>534-537-540>543.
     Small Craft Advisory from midnight tonight to 6 PM EDT Monday
     for ANZ532>534-537-540>543.

&&

$$

SYNOPSIS...ADS
NEAR TERM...ADS/KLW
SHORT TERM...ADS
LONG TERM...ADM
AVIATION...ADS/KLW/ADM
MARINE...ADS/KLW/ADM