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625
FXUS61 KLWX 271803
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
203 PM EDT Sat Apr 27 2024

.SYNOPSIS...
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Surface high pressure moves south along the eastern Appalachians
today. A warm front lifts through the area by Sunday bringing a
significant warm up heading into early next week. The next chance
for widespread precipitation arrives with a series of cold fronts
Tuesday into Wednesday next week.
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.NEAR TERM /THROUGH TONIGHT/...
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A band of light to moderate showers continues to move east across
the region, located around the I-95 corridor at this time. Most
guidance had this band of showers dissipating earlier, but it
is holding strong. Think this trend continues as it moves to our
east, so have increased POPs this afternoon further east. Expect
around a tenth of an inch of rainfall or so, perhaps two tenths
in some of the heavier elements. Not seeing much in terms of
lightning potential however, as instability remains zero over
the entire area.

As we move into the evening hours, another round of showers may
slide across the region from the west. Again, most guidance tears
this band apart, and I am inclined to buy that trend as the energy
associated with that band of showers is a bit weaker.

Most areas should be dry by midnight with cloudcover gradually
decreasing through daybreak. Lows tonight will be mild in the
50s.
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.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
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Well above normal temperatures Sunday into Monday as a deep ridge
moves across the Southeast and Mid-Atlantic states. Highs are forecast
to reach the low to mid 80s Sunday, then mid to upper 80s Monday
with a few spots hitting 90F. Even in the mountains, highs are
forecast to reach the 70s both days. A couple of climate sites
could tie or be near their daily record highs for April 30 /
Monday. Very mild overnight lows mostly in the 60s, with 50s in
the mountains. A few showers and thunderstorms are possible each
afternoon.
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.LONG TERM /TUESDAY THROUGH FRIDAY/...
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High pressure will remain off the southeast coast Tuesday while a
cold front approaches from the Ohio Valley. A lee trough will likely
be situated across the local area. Showers, and eventually
thunderstorms, will develop across the area in response to the
surface features and a shortwave trough aloft. With dew points only
around 60F, instability will be on the weaker side of the spectrum.
Bulk shear values around 30 kt would support some strong storms if
enough instability can develop. Increasing clouds may knock a few
degrees off temperatures, but it will still be very warm with highs
in the mid 80s to around 90. Some showers and storms could linger
into the night depending on the timing of the forcing.

The front will likely push through the area by Wednesday and the
influence of high pressure in New England will likely stabilize the
area. However, temperature/dew point contrast behind the front won`t
be high, with highs still well above normal in the upper 70s to mid
80s. What`s left of the front will lift back northward Thursday in
response to low pressure moving into the Great Lakes. Thursday
should be dry for most of the area as forcing remains to the west.

Timing of the system`s progression then becomes more uncertain.
Therefore a chance of showers and thunderstorms will persist through
Friday and Saturday. Temperatures will remain well above normal
during this time.
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.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
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Moderate showers are now along/east of the I-95 corridor, bringing
some moderate showers to BWI/MTN at this time. Elsewhere, after
some earlier VSBY restrictions from these showers, conditions
are improving. CIGs remain MVFR however, and will around there
through the early evening before improvement arrives.

VFR conditions return this evening and remain in place through
Monday as high pressure builds across the region. Winds vary between
southwest to west at around 5-10 knots Sunday through Monday.

There is a chance of showers and thunderstorms Tuesday afternoon and
evening ahead of a cold front. Southwesterly wind gusts up to 20 kt
are possible Tuesday afternoon. VFR conditions are expected
Wednesday and Thursday with light winds.
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&&

.MARINE...
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Southeast to south winds around 10-15 knots continue most of
the day today with a few light showers possible.

Southerly channeling is expected to produce SCA conditions once
again late this afternoon into tonight, mainly in the main channel
of the Chesapeake Bay. Some surrounding tidal rivers and bays on the
Eastern Shore could see SCA winds this evening, though confidence is
too low to issue a SCA at this time.

High pressure builds over the region Sunday into Monday, keeping
winds below SCA levels. Winds vary from southwest to west at or
around 10 knots.

Marginal SCA conditions are possible Tuesday in southwest flow.
There is a chance of showers and thunderstorms Tuesday afternoon and
evening, which could bring strong wind gusts. High pressure will
likely provide lighter winds Wednesday and Thursday.
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&&

.TIDES/COASTAL FLOODING...
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Tidal anomalies seem to be on the decrease at this time, so no
further tidal flooding is expected over the next several high
tide cycles at this time for most areas. DC could remain somewhat
elevated for the next high tide cycle or two, so perhaps could
be close during the Sunday morning high tide, but the trend is
certainly down at this time.

A steady southwest flow could bring some water up the Chesapeake
Bay early in the week, but it isn`t the most favorable direction
to cause tidal issues.
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&&

.CLIMATE...
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Near-record to record warmth is possible on Monday afternoon.
Below is a list of record high temperatures for April 29th, and
the year the record was set.

                                       Apr 29th
Climate Site                  Record High     Forecast High
Washington-National (DCA)     91F (2017+)     90F
Washington-Dulles (IAD)       89F (2017)      89F
Baltimore (BWI)               91F (1951)      88F

+ denotes that multiple years reached this value, but the depicted
  year is the most recent.
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&&

.LWX WATCHES/WARNINGS/ADVISORIES...
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DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory from 5 PM this afternoon to 4 AM EDT
     Sunday for ANZ531>534-537-543.
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&&

$$

SYNOPSIS...KRR
NEAR TERM...CJL
SHORT TERM...CJL/KRR
LONG TERM...ADS
AVIATION...ADS/CJL
MARINE...ADS/CJL
TIDES/COASTAL FLOODING...CJL
CLIMATE...CJL