206
FXUS61 KLWX 091845
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
245 PM EDT Fri Oct 9 2026
.WHAT HAS CHANGED...
Added a mention of possible gale conditions over the lower
Chesapeake Bay on Sunday as a result of passing remnants of
Hurricane Isaias.
&&
.KEY MESSAGES...
- 1) Remnants of Hurricane Isaias to bring rain, breezy
conditions Sunday into Sunday night.
- 2) No hazardous weather expected next week.
&&
.DISCUSSION...
KEY MESSAGE 1...Remnants of Hurricane Isaias to bring rain,
breezy conditions Sunday into Sunday night.
The pattern remains quiet through the first half of the weekend
as surface high pressure strengthens over the northeastern U.S.
However, this lengthy period of tranquil weather will come to an
end as this ridge retreats northward ahead of Isaias. Until
then, a thick area of high cirrus should continue to track
poleward. Daily highs will be in the low/mid 70s, with 60s
across mountain locations.
The main weather impact to the region over the next week is going to
be from the remnants of what is now Hurricane Isaias (Cat 3
strength). Model guidance is in generally good agreement that
Hurricane Isaias` surface low weakens and broadens as the system
moves into the TN Valley Saturday night into Sunday. The mid-
level circulation amplifies and becomes a strong cutoff low over
KY/TN that moves slowly east across the Mid- Atlantic Sunday
into Monday. Periods of rain are likely across the area at times
Saturday evening through Sunday night. Rainfall amounts of 1-2
inches are expected across the area. Higher rain totals are
certainly possible, but will depend on a few other smaller scale
features.
Tropical moisture surges north into our area Saturday night into
Sunday, with the highest PWAT values at or above 2" (most likely
east of the Blue Ridge). While the main cutoff low associated with
the remnants of Isaias remain west of the Appalachians on Saturday,
expect light rain to move in from south to north in the evening.
Forcing for ascent increases Saturday night, and especially Sunday
morning into Sunday afternoon as mid-level heights fall with the
approach of the cutoff low. There is going to be enhanced low-level
convergence somewhere over the region as the surface high to the
east and cutoff low to the west interact. Easterly flow into the
Blue Ridge could also produce enhanced rain amounts due to
orographic effects. Additionally, an inverted trough or wave of low
pressure tries to develop in lee of the Appalachians Sunday as it
crosses Virginia to the Delmarva.
Uncertainty remains regarding the exact evolution and timing of
these features, which will ultimately determine where / if any
locally heavy rain occurs. Continue to monitor the forecast over the
next couple of days. No Flood Watches are planned at this time as we
are still over 48 hours from the main slug of rain.
Additionally, there is a non-zero risk of isolated tornadoes on
Sunday. These post-tropical environments can be tricky as low-
level spin ups do occur. For now, the Storm Prediction Center
has maintained a Day 3 Marginal Risk area.
It is going to be noticeably breezy, especially in the mountains
where winds begin to pick up Saturday evening. The strongest winds
are most likely on Sunday. The current forecast for peak wind gusts
is 30-40 mph in the Alleghenies and 20-30 mph elsewhere.
Conditions dry out Monday morning into Monday afternoon as the
remnants of Isaias push offshore. Looking at mostly mild
temperatures for most of next week. A series of cold fronts cross
the region during the middle to late part of next week as the
synoptic pattern becomes more active. Aside from mountain rain
showers, most of the area looks to remain dry. The strongest cold
front arrives late next week, possibly bringing rain and colder air
behind it.
KEY MESSAGE 2...No hazardous weather expected next week.
In the wake of the remnants of Isaias, high pressure will build
briefly over the area Monday night and Tuesday. A mainly dry cold
front will move across the area late Tuesday night, but may bring
some scattered-numerous rain showers to the Allegheny Mountains late
Tuesday night into Wednesday in upslope flow.
Temperatures will start trending cooler during the middle and second
half of next toward near normal.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR conditions expected throughout the day Saturday. Beginning
Saturday night and into Sunday, lowering CIGs and VSBYs are
anticipated as the remnants of Hurricane Isaias move in from the
west. Low clouds and reduced visibility from steady rain will be the
primary impacts. While not directly impacting forecasted airfield
sites, some low-level wind shear is possible across the Blue Ridge
on Sunday morning as the system approaches for any low-flying
aircraft. Wind gusts up to 20-30 knots possible throughout the day
Sunday as the system moves through.
As the system begins to transition east offshore late Sunday into
Monday, winds should diminish. VFR conditions return Monday and
Tuesday as weak high pressure builds in.
&&
.MARINE...
Winds stay below SCA criteria through Saturday afternoon, then
gradually pick up overnight. Remnants from Hurricane Isaias will
track through the Mid-Atlantic throughout the day Sunday, with winds
up to 30 knots across the Chesapeake Bay possible. Winds will be
stronger to the south, and could approach gale thresholds before
diminishing some overnight as the system passes through. Winds
likely stay within SCA criteria through Monday, diminishing by
Tuesday.
&&
.TIDES/COASTAL FLOODING...
Minor coastal flooding seems likely at sensitive locations Sunday
evening due to rising water levels due to strengthening east to
southeast winds combined with high astronomical tides due to a new
moon. Based on the latest forecast, Annapolis could near
moderate flooding levels on Sunday evening, but confidence is
low at this time. Winds turn offshore Monday allowing tide
levels to recede.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory from 4 AM to 7 PM EDT Sunday for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory from 4 AM to 7 PM EDT Sunday for ANZ530-
531-535-538-539.
Small Craft Advisory from 1 AM to 7 PM EDT Sunday for ANZ532-
533-536-540>542.
Small Craft Advisory from 7 PM Saturday to 7 PM EDT Sunday for
ANZ534-537-543.
&&
$$
DISCUSSION...LFR/BRO/KRR/SRT
AVIATION...LFR/KRR/SRT
MARINE...LFR/KRR/SRT
NWS LWX Office Area Forecast Discussion