Area Forecast Discussion Issued by NWS Sterling, VA
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000
FXUS61 KLWX 191404
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1004 AM EDT Thu May 19 2022
.SYNOPSIS...
After a warm front lifts north of the region this morning, a
weak cold front will nose into the region this afternoon. The
front will then return northward as a warm front Friday. A
stronger cold front is expected to approach from the Midwest
over the weekend, likely crossing the region late Sunday into
Monday. The front may stall nearby early next week.
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.NEAR TERM /THROUGH FRIDAY/...
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Temperatures have been slow to moderate this morning due to the
eroding clouds lingering on a little longer than most guidance
had, but otherwise forecast remains on track. Keeping an eye on
the late tonight into Friday morning timeframe for where the
remnants of an MCV tracks. Otherwise, previous discussion
follows.
Today will be warmer than Wednesday with highs into the 80s for
most, some clouds, and westerly breezes.
The cold front that drops through today will return northward as
a warm front tonight. There are hints of a wave aloft forming as
a result of thunderstorms over the Plains. This wave may crest
over the warm front Friday, and could bring some showers and
thunderstorms. There is a conditional risk of strong to severe
storms given much stronger CAPE (2000+ J/kg) and modest mid-
level flow (i.e. 25-35 kt 850-500 hPa).
After a mild and muggy start Friday morning, temperatures may
crack 90 over much of the area Friday afternoon. Heat index
values in the mid to upper 90s are possible.-- End Changed Discussion --
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.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
Ridging will build over the area aloft through Saturday as
Bermuda high pressure sets up offshore. This will likely result
in record heat, with heat index values of 95 to 100. It will be
very unstable, but with less shear and not much of a trigger,
thunderstorm risks may be limited to terrain circulations near
and west of the Blue Ridge Mountains during the afternoon and
early evening. A wave of low pressure may develop over the
Midwest, which could subtly enhance convective activity near the
Alleghenies late Saturday.
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.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
On Sunday morning, low pressure will likely be near or east of
Michigan, with a cold front trailing to the southwest. This slower
trend to the front means one more hot day is becoming increasingly
likely for Sunday. Thicknesses will be a little lower, and clouds
may begin to increase, so lower to perhaps mid 90s is the most
likely outcome. Showers and thunderstorms will be developing along
the front and/or a prefrontal trough as they progress eastward
during the afternoon. With a lack of upper level support and
marginal shear, thunderstorm coverage and intensity is in question,
but it still looks like a potentially active period during the
afternoon and evening.
The front may not push fully through the area until early Monday,
but there is good model agreement that it will push far enough south
to result in a much cooler day. However, confidence lowers on
precipitation chances for Monday and Tuesday as the front likely
lurks to the south and high pressure to the north builds southward
along the Appalachains. Should more pronounced waves of low pressure
develop along the front, it would result in greater rain chances.
Overall, it`s looking like a cooler and more unsettled period. By
Wednesday, the front may try to return northward as low pressure
moves into the Great Lakes. This will keep a chance of showers in
the forecast, albeit with slightly warmer temperatures.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
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VFR conditions are expected through Saturday outside of any
TSRA, the chance of which remains low/conditional overall.
Light and variable winds early this morning will shift to
westerly by mid to late morning. Winds may gust 20-25 knots this
afternoon as a weak cold front crosses. S/SW flow returns Friday
into Saturday with a few gusts of 15-20 knots possible at times.
Cold front approaches Sunday afternoon and exits early Monday.
Showers and thunderstorms will be possible with passage. The front
will likely stall to the south Monday, which could result in some
showers and intermittent sub-VFR ceilings.-- End Changed Discussion --
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.MARINE...
S flow will pivot to W by mid morning, abating over the mid bay
and lower tidal Potomac by late morning. Near shore W gusts are
likely this afternoon. Thereafter, light winds are expected
overall through Saturday, though near shore gustiness is
possible during the afternoon, with southerly channeling kicking
up winds over the open waters possible at night. A few
thunderstorms are possible at times through Saturday, but
chances remain low.
Small Craft Advisories may be needed for portions of Sunday into
early Monday as a cold front crosses and shifts winds from southwest
to northwest. Gusty thunderstorms are also possible. Lighter winds
are expected by Monday.
&&
.TIDES/COASTAL FLOODING...
Stronger southerly winds have pushed water up the bay overnight, and
it appears Annapolis will reach minor flood thresholds this morning.
It will be close at Baltimore, Havre de Grace and DC SW Waterfront,
so will monitor for potential advisories there as the morning
progresses. As a front slips to the south today, winds will shift
and anomalies should decrease.
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.CLIMATE...
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Hot weather is forecast Friday through Sunday with temperatures
likely 10 to 20 degrees above normal. Below is a list of
temperature records Friday through Sunday (May 20th-22nd).
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Record Daily High Temperatures for May 20th
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Washington DC area........96 F (set in 1996)..................
Baltimore MD area.........95 F (set in 1962)..................
Sterling/Dulles VA area...93 F (set in 1996)..................
Martinsburg WV area.......97 F (set in 1911)..................
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Record Daily Warm Low Temperatures for May 21st
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Washington DC area........71 F (set in 1996)..................
Baltimore MD area.........71 F (set in 1934)..................
Sterling/Dulles VA area...67 F (set in 2013 and 1996).........
Martinsburg WV area.......65 F (set in 1996 and 1911).........
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Record Daily High Temperatures for May 21st
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Washington DC area........95 F (set in 1934)..................
Baltimore MD area.........96 F (set in 1934)..................
Sterling/Dulles VA area...92 F (set in 1996)..................
Martinsburg WV area......100 F (set in 1934)..................
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Record Daily Warm Low Temperatures for May 22nd
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Washington DC area........71 F (set in 1959)..................
Baltimore MD area.........71 F (set in 1903)..................
Sterling/Dulles VA area...67 F (set in 1975)..................
Martinsburg WV area.......68 F (set in 1959)..................
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Record Daily High Temperatures for May 22nd
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Washington DC area........96 F (set in 1941)..................
Baltimore MD area.........98 F (set in 1941)..................
Sterling/Dulles VA area...89 F (set in 2021)..................
Martinsburg WV area.......98 F (set in 1934)..................
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Temperature records for the Washington DC area have been
recorded at what is now Ronald Reagan Washington National
Airport (KDCA) since 1941. The official weather record consists
of that data back to 1945, and observations taken in downtown
Washington from 1872 through 1944.
Temperature records for the Baltimore MD area have been
recorded at what is now Baltimore-Washington International
Thurgood Marshall Airport (KBWI) since 1950. The official
weather record consists of that data, and observations taken in
downtown Baltimore from 1872 through 1949.
Temperature records for the Sterling/Dulles VA area have been
recorded at what is now Washington Dulles International Airport
(KIAD) since 1960. The official weather record consists solely of
that data.
Temperature records for the Martinsburg WV area have been
recorded at what is now Eastern West Virginia Regional Airport
(KMRB) since 1938. The official weather record consists of that
data back to 1944, and observations taken in downtown
Martinsburg from 1891 through 1943.
All climate data is considered preliminary until reviewed and
certified by the National Centers for Environmental Information
(NCEI).-- End Changed Discussion --
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
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DC...None.
MD...Coastal Flood Advisory until 11 AM EDT this morning for MDZ014.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for
ANZ530>532-535-538.
Small Craft Advisory until noon EDT today for ANZ533-534-536-
537-541>543.-- End Changed Discussion --
&&
$$
SYNOPSIS...DHOF
NEAR TERM...DHOF/CPB
SHORT TERM...DHOF/CPB
LONG TERM...ADS
AVIATION...ADS/DHOF/CPB
MARINE...ADS/DHOF/CPB
TIDES/COASTAL FLOODING...ADS
CLIMATE... LWX