428
FXUS61 KLWX 191929
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
329 PM EDT Tue May 19 2026
.WHAT HAS CHANGED...
Nothing.
&&
.KEY MESSAGES...
- Record heat continues through Wednesday. A strong cold front brings
widespread strong to severe thunderstorm chances Wednesday
afternoon and evening.
- Conditions remain showery and cool Thursday into early next
week, bringing much needed rain to the region.
&&
.DISCUSSION...
KEY MESSAGE 1...Record heat continues through Wednesday. A strong cold
front brings widespread strong to severe thunderstorm chances
Wednesday afternoon and evening.
KEY MESSAGE 1 DESCRIPTION...
Scattered showers and thunderstorms have developed over the
Shenandoah River Valley along a lee-side trof in a hot unstable
air mass. These thunderstorms will track to the ENE around 10 kt
reaching the metros after 5 PM and dissipating by 9 PM, if not
sooner. Warm and muggy night on tap with lows in the 70s.
A lee-side trof will develop Wed afternoon well ahead of a
strong cold front expected to move through the area late Wed
night. Expect numerous showers and thunderstorms Wed afternoon
into the early evening with a threat of mainly downburst winds
given very hot and unstable air mass. Believe there will be
enough coverage of severe thunderstorms for a Severe
Thunderstorm Watch to be issued. Convection should start to
wane after 9 PM, but showers could linger well into the
overnight as cdfnt crosses the area.
KEY MESSAGE 2...Conditions remain showery and cool Thursday into early next
week, bringing much needed rain to the region.
KEY MESSAGE 2 DESCRIPTION...
The synoptic scale pattern will remain relatively stagnant through
the long term period, with weak upper troughing off to our west over
the Ohio Valley, and surface high pressure off to our north and
northeast. This will lead to a pattern where marine influence low-
level easterly flow is nearly continuously overrun by south to
southwesterly flow aloft. This persistent warm advection regime
aloft atop stable low-level air will lead to cloudy skies with on
and off showers Thursday through Monday. This will bring much
needed, beneficial rains to the forecast area, with ensemble means
showing around one to two inches of rain across much of the forecast
area during that time.
Highs Thursday will take a 25 to 30 degree dive behind the front
with many locations struggling to push 70 degrees. Temperatures
will continue to run below normal on Friday, struggling to make it
into the 60s. Ensemble guidance shows much larger spread in
temperatures Saturday through Monday, with some solutions keeping us
locked into low cloud cover and temperatures in the 50s/60s, while
some other solutions try to break us out of the low clouds, causing
temperatures to climb into the 70s.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Prob30 group added for all terminals this afternoon mainly
between 20Z-00Z. Numerous showers and thunderstorms Wed
afternoon.
Some low CIGS may hang on through Wednesday night before
lifting Thursday as the front sits south of the region. Periodic
rain showers moving through the region on Thursday afternoon
and evening bring additional sub-VFR periods at terminals Wind
gusts could reach 15-20 knots on Thursday before gradually
decreasing. Sub-VFR conditions appear likely on Friday and
Saturday in association with low clouds and showers. Winds will
generally be out of the east to southeast on both Friday and
Saturday.
&&
.MARINE...
SCA southerly channeling can be expected again this afternoon and
evening. Winds will remain out of the south and southwest with gusts
up to 25 kts.
Winds may near low-end SCA levels in south to southwesterly flow on
Wednesday, and then again in northerly flow on Thursday. SMWs appear
possible Wednesday into Wednesday night as thunderstorms move over
the waters.
East to southeasterly winds may near low-end SCA levels late
Thursday through Saturday.
&&
.CLIMATE...
Here are some daily temperature records during the May 19-20,
2026 timeframe:
A `+` sign indicates multiple years currently hold that record.
A `!` sign indicates the record is forecast to be tied or broken.
***TUESDAY, MAY 19TH, 2026***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
Washington-National (DCA) 96F (1997)+ 72F (2015)!
Washington-Dulles (IAD) 92F (1997)+! 66F (2017)+!
Baltimore (BWI) 98F (1962) 75F (1877)
Baltimore Inner Harbor (DMH) 98F (1962) 78F (1962)
Martinsburg (MRB) 98F (1911) 69F (1996)!
Charlottesville (CHO) 97F (1962) 72F (1997)
Annapolis (NAK) 96F (1962) 71F (1911)!
Hagerstown (HGR) 97F (1996) 69F (2017)+!
***WEDNESDAY, MAY 20TH, 2026***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
Washington-National (DCA) 96F (1996) 73F (2019)
Washington-Dulles (IAD) 93F (1996) 69F (2019)
Baltimore (BWI) 95F (1962) 71F (2019)+
Baltimore Inner Harbor (DMH) 97F (1962) 74F (1998)+
Martinsburg (MRB) 97F (1911) 70F (1998)
Charlottesville (CHO) 96F (1996) 73F (1996)
Annapolis (NAK) 98F (1997) 76F (1898)
Hagerstown (HGR) 97F (1996) 66F (1998)
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until 2 AM EDT Wednesday for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 2 AM EDT Wednesday for ANZ530>534-
537>543.
Small Craft Advisory from 3 PM to 8 PM EDT Wednesday for
ANZ534-543.
&&
$$
DISCUSSION...LFR/KJP
AVIATION...LFR
MARINE...LFR
NWS LWX Office Area Forecast Discussion