325
FXUS61 KLWX 190131
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
931 PM EDT Sat May 18 2024

.SYNOPSIS...
Low pressure will drift off the Carolina Coast through Sunday.
High pressure will build overhead Monday into Tuesday. A cold
front will approach from the Midwest Wednesday, then cross by
Friday.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
A longwave trough axis is positively tilted from New England to
the Tennessee Valley. Primary stationary front is located across
North Carolina, but a secondary wind shift appears to be located
across Pennsylvania. A shortwave trough is departing to the
east, taking earlier rain with it. Most of the night should
largely be dry, but a few showers could develop late tonight as
the convergence axis drop south into the area. Most guidance
indicates the isolated shower chance along the I-95 corridor.

Breaks in the clouds have been occurring in the Potomac
Highlands, and this may continue into the night, possibly
including the Shenandoah Valley. This area will have the
greatest chance of fog development. Low clouds will remain in
place across much of the rest of the area. Low temperatures will
be in the 50s to near 60.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
Sunday starts off with cloud cover over most of the area, with
possible breaks along our western periphery similar to today.
Shower activity on Sunday appears to be less than previously
forecast since the system responsible has made a swift exit and
high pressure builds in from the north, but a few showers and
isolated thunderstorms can`t be ruled out in the afternoon quite
yet, primarily west of the Blue Ridge. Cloud cover will
decrease through the day and high temperatures are expected to
reach into the 70s for much of the area. Low temperatures will
be in the 50s. With available moisture from recent rainfall and
high pressure moving in, some fog could develop late Sunday
night into Monday morning.

Monday begins our reprieve from unsettled conditions with dry
weather and sunny skies in the forecast. High temperatures rise
to the mid-upper 70s, starting a warming trend as well.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
A broad upper level ridge is forecast to be remain in place over the
eastern seaboard on Tuesday with high pressure at the surface. A
southerly return flow will lead to increasingly warming
temperatures through the middle parts of next week. The SFC high
pressure on Tuesday will keep the region dry, but an approaching
cold front from the west will bring increasing chances for showers
and thunderstorms Wednesday through Friday. Model guidance has
trended slower with the mid-week system and there remains some
uncertainty if there will be enough instability (CAPE) that overlaps
with the favorable period for shear to produce a threat for severe
weather. SPC is focusing on the Ohio Valley for SVR weather
Wednesday into Thursday, but the CIPS machine learning model
continues to suggest that there is a chance for isolated severe
weather in our region during the middle and later parts of next
week.

&&

.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
Forecast is somewhat uncertain for the next several hours as
most guidance is not capturing the current ceilings teetering
between MVFR and VFR. There is a general consensus of decreasing
ceilings through the night, most likely to IFR. This could occur
as early as 04-06Z or as late as 08-10Z. There is a lower
probability of LIFR ceilings. The greatest chance for
visibility reduced in fog will be for MRB and CHO. Any shower
chance will be isolated/light for the remainder of the night.

Conditions should improve to VFR by late morning/early afternoon
on Sunday as high pressure builds in.

VFR conditions are favored Tuesday through Friday with winds likely
to be out of the south to southeast.  Brief aviation restrictions
will be possible with shower and thunderstorms Wednesday through
Friday.

&&

.MARINE...
Wind forecast has been trending downward for tonight, and
observations are backing that up. Therefore may be canceling the
existing Small Craft Advisory. E/SE winds become N/NE by Sunday
morning. High pressure builds in on Sunday and winds remain
sub- SCA and out of the E/NE through Monday.

Sub-SCA conditions are favored on Tuesday, but a southerly
channeling flow on Wednesday may require Small Craft Advisories.

&&

.TIDES/COASTAL FLOODING...
Persistent onshore flow (albeit light) is expected to persist into
early next week. Repeated rounds of flooding are possible,
especially along vulnerable shoreline. Given the light nature of the
flow, flooding should stay in the minor realm. Have reconfigured
advisories based on the latest forecast. In short, Straits
Point, Annapolis, and DC SW Waterfront are most likely to see
minor flooding, especially during the higher high tide cycles.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Coastal Flood Advisory until 7 PM EDT Sunday for DCZ001.
MD...Coastal Flood Advisory until 7 AM EDT Sunday for MDZ014.
     Coastal Flood Advisory until 2 AM EDT Sunday for MDZ017.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 6 AM EDT Sunday for ANZ534-537-543.

&&

$$

SYNOPSIS...DHOF
NEAR TERM...ADS
SHORT TERM...CAS
LONG TERM...JMG
AVIATION...ADS/JMG/CAS
MARINE...ADS/JMG/CAS
TIDES/COASTAL FLOODING...ADS