Bel Air South, Maryland 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

545
FXUS61 KLWX 220124
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
924 PM EDT Sat Jun 21 2025

.SYNOPSIS...
A prolonged period of very hot weather is expected Sunday
through the middle part of next week as a large ridge of high
pressure builds over the eastern United States. A risk of
showers and thunderstorms returns during the middle to latter
portions of the week as a frontal system approaches from the
north.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
Evening update: Earlier cumulus clouds are dissipating with loss
of daytime heating. Just a few passing cirrus clouds remain
aloft. No major changes were made to the forecast for tonight.
Previous discussion follows...

Return flow will help increase temperatures and dew points
heading into tonight. Forecast lows should mainly range from
the mid 60s to low 70s, while being closer to 75 degrees in D.C.
and Baltimore. Mainly clear skies will prevail, with only a few
patches of valley fog possible.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
The anomalous mid/upper ridge spreads eastward Sunday and
Monday, while the surface high shifts southward. This allows for
increasing heat each day. Interestingly, given the position of
the ridge, higher dew points may be found rotating clockwise to
our north, so it`s possible Pennsylvania will have higher dew
points than Virginia, at least for Sunday. Air temperatures
reach the mid to upper 90s Sunday with heat index values near or
above 100 in much of the area. This warrants a Heat Advisory
west of the Blue Ridge where criteria is 100. On Monday, air
temperatures should tick up slightly more, with upper 90s to
around 100 expected. W/NW winds may increase mixing (with the
help of downsloping), which would support hotter temperatures
and lower dew points, but still resulting in heat index values
of 100-110 for much of the area. An Extreme Heat Watch has been
issued for northern portions of the area. West of the Blue
Ridge, heat index values should easily approach 105. To the
east, reaching 110 is a little more uncertain, but it may be
close in some areas, so thought it was worth highlighting with
a Watch so people can start preparing for what will be an
extended period of very hot conditions. Overnights will not
offer much relief, with 60s relegated to the higher elevations,
and downtown Washington and Baltimore potentially staying in the
80s. For those vulnerable to the heat, please ensure to find
ways to stay cool and hydrated, particularly at night. The
following website provides more about heat safety:
weather.gov/safety/heat.

Overall, the strong ridge should suppress convective
development. Terrain circulations and bay breeze convergence
could always be the source of a rogue shower/storm, however. SPC
also notes outflow from MCSs well to our north could also be a
trigger on Sunday afternoon, as depicted in the 12Z WRF-ARW.
Therefore, they painted a broad conditional Marginal Risk for
severe thunderstorms that includes northeastern Maryland
(meaning storm development is very uncertain, but if they do
develop, they could turn locally severe). One minor change to
the forecast this evening was to add mentionable PoPs in
northeastern MD late Sunday afternoon into Sunday evening.
Chances for thunderstorm development look to be very low, but if
storms were to form, the environment (characterized by high
CAPE, high DCAPE, and steep lapse rates in the low-mid levels)
looks to be very favorable for strong winds. The only other
weather of note through the period is potential for patchy river
valley fog during the overnights.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
A ridge of high pressure will remain in place into at least the
middle of next week. Hot and humid conditions are expected during
this time. High temperatures are expected to be in the middle to
upper 90s each day, possibly reaching the lower 100s in the metros
Monday and Tuesday. Heat index values could reach 100 to 110 in many
places. Low temperatures at night will be persistently in the middle
70s to near 80. The next chance for showers or thunderstorms is
Tuesday afternoon or evening, but an even higher chance of showers
and thunderstorms is evident on Wednesday when the ridge of high
pressure begins to flatten or weaken. Additional thunderstorm
chances remain through the end of the work week as a frontal zone
slowly approaches from the north.

&&

.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
VFR conditions are expected through the weekend and into early
next week with strong high pressure in place, although diurnal
cumulus development will occur. Winds will be around 10 knots
or less, with southerly winds through tonight turning more
westerly or northwesterly Sunday and Monday. Can`t totally rule
out a rogue shower or storm on the bay breeze each afternoon
near MTN (as was seen earlier today).

VFR conditions at all terminals Tuesday through Tuesday night. A few
restrictions cannot be ruled out on Wednesday given a slight chance
for afternoon/evening thunderstorms. Winds northwest 5 to 10 knots
through the period.

&&

.MARINE...
High pressure across the area has kept marine wind gusts
mainly at 10 knots or less, with diurnal wind shifts noted.
However, this ridge is moving offshore with southerly channeling
picking up this evening into the overnight hours. Consequently,
gusts up to 20 knots are possible over the Chesapeake Bay with
a Small Craft Advisory in effect. A second period of southerly
channeling may occur Sunday evening, but it currently looks more
marginal and brief. Lighter winds are expected Monday. While
unlikely, a rogue shower or storm could pop up along the
shore/bay breeze convergence each afternoon.

Sub-SCA winds for Tuesday through Wednesday night. Winds northwest 5
to 10 knots through the period. A slight chance of thunderstorms on
Wednesday afternoon/evening could bring brief hazardous conditions
to the waters.

&&

.TIDES/COASTAL FLOODING...
A return to southerly flow will nudge tidal anomalies higher
through Sunday. Although flooding is not forecast at this time,
some guidance has Annapolis in particular very close to minor
flood stage during the evenings this weekend.

&&

.CLIMATE...
Here are some daily high temperature records during the June 21-27
timeframe:

A `+` sign indicates multiple years currently hold that record.

                   ***SATURDAY, JUNE 21ST, 2025***
LOCATION                   RECORD HIGH (YEAR)  RECORD WARM LOW (YEAR)
Washington-National (DCA)      99F (2012)          78F (2012)
Washington-Dulles (IAD)        98F (1988)          71F (2015)
Baltimore (BWI)               100F (2012)+         79F (1931)
Baltimore Inner Harbor (DMH)  103F (2012)          82F (2012)
Martinsburg (MRB)             102F (1931)          72F (2015)+
Charlottesville (CHO)          99F (1933)          77F (1924)
Annapolis (NAK)               100F (1988)          78F (2012)+
Hagerstown (HGR)               97F (1923)          72F (2012)+

                  ***SUNDAY, JUNE 22ND, 2025***
LOCATION                   RECORD HIGH (YEAR)  RECORD WARM LOW (YEAR)
Washington-National (DCA)     101F (1988)          78F (2015)
Washington-Dulles (IAD)       100F (2024)          75F (2024)
Baltimore (BWI)               101F (2024)          77F (1933)
Baltimore Inner Harbor (DMH)  104F (1988)          84F (1988)
Martinsburg (MRB)             102F (1933)          71F (1934)
Charlottesville (CHO)         101F (1933)          76F (1933)
Annapolis (NAK)               101F (1988)          81F (1896)
Hagerstown (HGR)              100F (1988)          76F (2024)

                 ***MONDAY, JUNE 23RD, 2025***
LOCATION                   RECORD HIGH (YEAR)  RECORD WARM LOW (YEAR)
Washington-National (DCA)      99F (2024)          81F (2024)
Washington-Dulles (IAD)        98F (2024)          78F (2024)
Baltimore (BWI)                98F (2024)          81F (2024)
Baltimore Inner Harbor (DMH)   99F (2024)+         83F (2024)
Martinsburg (MRB)             100F (1934)          72F (2024)+
Charlottesville (CHO)         100F (1894)          76F (1996)
Annapolis (NAK)                98F (1988)          77F (2011)
Hagerstown (HGR)               98F (2010)          78F (2024)

                 ***TUESDAY, JUNE 24TH, 2025***
LOCATION                   RECORD HIGH (YEAR)  RECORD WARM LOW (YEAR)
Washington-National (DCA)     100F (2010)          78F (2010)
Washington-Dulles (IAD)        97F (2010)          73F (2010)
Baltimore (BWI)               100F (2010)          76F (2010)+
Baltimore Inner Harbor (DMH)  101F (2010)+         82F (2010)
Martinsburg (MRB)              97F (1943)          70F (2024)+
Charlottesville (CHO)         101F (1930)          74F (1914)
Annapolis (NAK)                97F (2000)+         81F (1896)
Hagerstown (HGR)               96F (2010)+         75F (2010)

                 ***WEDNESDAY, JUNE 25TH, 2025***
LOCATION                   RECORD HIGH (YEAR)  RECORD WARM LOW (YEAR)
Washington-National (DCA)     100F (1977)          76F (2010)+
Washington-Dulles (IAD)        97F (1966)          71F (1981)
Baltimore (BWI)                99F (1997)          77F (1949)+
Baltimore Inner Harbor (DMH)  104F (1997)          79F (1998)+
Martinsburg (MRB)              99F (1997)          72F (1949)
Charlottesville (CHO)          99F (1997)          77F (1951)
Annapolis (NAK)                98F (2000)+         78F (1997)+
Hagerstown (HGR)               98F (1952)          75F (1949)

                 ***THURSDAY, JUNE 26TH, 2025***
LOCATION                   RECORD HIGH (YEAR)  RECORD WARM LOW (YEAR)
Washington-National (DCA)     101F (1952)          77F (1952)+
Washington-Dulles (IAD)        99F (2024)          72F (2023)+
Baltimore (BWI)                99F (2024)+         80F (1952)
Baltimore Inner Harbor (DMH)  104F (1998)          83F (1952)
Martinsburg (MRB)             102F (1943)          75F (1949)
Charlottesville (CHO)          99F (1998)          78F (1952)
Annapolis (NAK)                98F (1998)+         81F (1952)
Hagerstown (HGR)               98F (1954)+         75F (1952)

                 ***FRIDAY, JUNE 27TH, 2025***
LOCATION                   RECORD HIGH (YEAR)  RECORD WARM LOW (YEAR)
Washington-National (DCA)      99F (2010)          80F (1952)
Washington-Dulles (IAD)       100F (1964)          72F (2021)+
Baltimore (BWI)               100F (2010)          78F (1949)+
Baltimore Inner Harbor (DMH)  101F (2010)          83F (1998)
Martinsburg (MRB)             101F (1943)          75F (1952)
Charlottesville (CHO)         100F (1952)          79F (1952)
Annapolis (NAK)                98F (1911)          79F (1943)
Hagerstown (HGR)               99F (2010)          77F (1952)

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Extreme Heat Watch from Monday morning through Monday evening
     for DCZ001.
MD...Small Craft Advisory until 4 AM EDT Sunday for MDZ008.
     Extreme Heat Watch from Monday morning through Monday evening
     for MDZ003>006-008-011-013-014-016-503>508.
     Heat Advisory from noon to 8 PM EDT Sunday for MDZ003-502.
VA...Extreme Heat Watch from Monday morning through Monday evening
     for VAZ027>031-053>055-502-505-506-526-527.
     Heat Advisory from noon to 8 PM EDT Sunday for VAZ027>031.
WV...Extreme Heat Watch from Monday morning through Monday evening
     for WVZ052-053.
     Heat Advisory from noon to 8 PM EDT Sunday for WVZ050>053-055-
     502-504.
MARINE...Small Craft Advisory until 4 AM EDT Sunday for ANZ530>534-
     537>541-543.
     Extreme Heat Watch from Monday morning through Monday evening
     for ANZ530.

&&

$$

SYNOPSIS...ADS
NEAR TERM...ADS/KJP
SHORT TERM...ADS/KJP
LONG TERM...KLW/DHOF
AVIATION...ADS/DHOF
MARINE...ADS/DHOF
TIDES/COASTAL FLOODING...ADS
CLIMATE...BRO