Gaithersburg, Maryland 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

800
FXUS61 KLWX 111425 AAA
AFDLWX

Area Forecast Discussion...UPDATED
National Weather Service Baltimore MD/Washington DC
1025 AM EDT Fri Jul 11 2025

.SYNOPSIS...
A weak front will remain nearby through the weekend with daily
showers and thunderstorms expected. A cold front pushes through the
forecast area early next week with another front approaching the
region by the end of the week.

&&

.NEAR TERM /THROUGH TONIGHT/...

12Z IAD sounding showed that atmosphere has dried out
considerably with PWATs nearly half inch lower since 24 hrs
ago. Significant drying/warming is also seen in the mid levels
on the three GOES WV channels. For today, height rises should
keep coverage isolated to widely scattered along the Blue Ridge
and Appalachian Mountains. Cell motion will be slow around 5
kt, so some brief heavy rain is possible.

Previous afd...

Weak upper level troughing shifts offshore throughout the day as a
front remains to the north. Upper level ridging slowly builds
overhead with temperatures expected to be slightly warmer
compared to yesterday. Highs rise into the 80s to low 90s for
most with those at higher elevations staying in the 70s. A moist
air mass will yield warm dew points with heat indices rising
into the mid to upper 90s for most.

Warm and moist conditions yield plenty of instability with afternoon
showers and thunderstorms expected. Recent model guidance has
convective activity primarily staying west of the Blue Ridge, where
the Storm Prediction Center has a Marginal risk. Should convection
initiate and become strong to severe, damaging wind gusts will be
the primary hazard due to conditions favorable for downbursts.

Convective activity is expected to dwindle this evening with
the loss of daytime heating. Dry conditions and low temperatures
in the 60s and 70s are expected across the forecast area.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Weak high pressure builds to the southwest through the weekend
as a low pressure system and associated cold front approach from
the central plains. Diurnally driven showers and thunderstorms
are expected each afternoon with precipitation chances
increasing each day. Despite weak forcing aloft, a warm and
moist airmass will lead to plenty of instability across the
forecast area. Sunday has the highest chances for strong to
severe thunderstorms with the Storm Prediction Center having a
Marginal Risk for the forecast area. Damaging wind gusts will be
the primary threat due to a threat for downburst within
convection.

High temperatures over the weekend will be in the upper 80s to
low 90s each day with only higher elevations staying in the low
80s. Overnight low temperatures drop into the 60s for most west
of the Blue Ridge and low to mid 70s elsewhere.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
The period begins with a weakening mid-level trough of low pressure
over the Great Lakes region, while a cold front approaches from the
northwest. Ahead of the cold front, Monday is expected to be an
active weather day with high PWATs and moderate CAPE available for
numerous thunderstorms. Cloud cover from this convection and the
approaching front should limit daytime temperatures to the mid 80s
(70s in the mountains), mitigating heat concerns. Despite this
reprieve, chances for isolated flash flooding and/or severe
weather on Monday will need to be monitored in the coming days.

By Tuesday morning, the front is expected to stall across or just
south of the area as weak southerly flow around a Bermuda High
advects warm, moist air northward into the region. As the week
progresses, temperatures should increase to seasonably warm values
with most areas seeing low temperatures in the 70s and high
temperatures in the mid-upper 80s outside of the highest elevations.
Daily chances of showers and thunderstorms are expected, with the
highest coverage occurring over the southern and western
counties.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...


VFR conditions continue through the weekend with the exception
of reduced visibilities and ceilings during afternoon showers
and thunderstorms. Winds remain out of the south/southeast each
day, blowing around 5 knots each afternoon through the weekend.
In addition to flight restrictions, gusty winds and lightning
are possible during thunderstorms.

Monday will likely be the most impactful weather day of the period,
with numerous showers and thunderstorms expected near all TAF sites.
Brief MVFR conditions are possible with any convection, some of
which may be severe. Outside of storms, winds on Monday will be
light from the S and SW, becoming N with the passage of a weakening
cold front overnight into Tuesday.

Tuesday through Thursday will feature light and variable winds, with
daily chances for showers and thunderstorms. KCHO and KMRB will have
the higher chances for convection each afternoon.

&&

.MARINE...
Southerly winds are expected to remain below Small Craft
Advisory criteria through the weekend, blowing 5 knots or less.
Showers and thunderstorms over the waters are possible each
afternoon, leading to a SMW threat, albeit low,  each day.
Otherwise, no marine hazards are expected.

Prevailing winds throughout the week are expected to remain below 10-
15kts, though funneling of southerly winds across the Lower
Chesapeake may lead to gustier winds Thursday. Marine hazards are
possible with any thunderstorms entering the waters each afternoon
and evening. Some storms may be severe on Monday and require
SMWs.

&&

.TIDES/COASTAL FLOODING...
A prolonged period of southerly winds will lead to elevated
tidal anomalies over the weekend. This carries most of the tidal
locations into Action stage, particularly during the higher of
the two astronomical high tide cycles. Sensitive locations,
such as Annapolis, are forecast to hit Minor stage during the
high tide cycle Sunday morning.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.

&&

$$

SYNOPSIS...AVS
NEAR TERM...LFR
SHORT TERM...AVS
LONG TERM...CPB
AVIATION...LFR/CPB
MARINE...LFR/CPB
TIDES/COASTAL FLOODING...AVS