-- Discussion containing changed information from previous version are highlighted. --
796
FXUS61 KLWX 271402
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1002 AM EDT Mon May 27 2024

.SYNOPSIS...
A warm and humid air mass will persist through today. A cold
front will push through the area tonight. A secondary cold
front moves in by mid-week before high pressure builds in by
Friday.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
As of 945 AM, rain showers are moving northeast across the area
along and west of the Blue Ridge with some isolated shower
activity in NE Maryland. Shower and thunderstorm activity to the
south of the forecast area has been weakening as it moves
through the area, likely due to residual cloud cover and cooler
temperatures from overnight rain showers. Looking at recent
visible satellite, mostly cloudy skies can be seen across much
of the forecast area with a thin layer of high level clouds
along and east of I-95. How cloud cover evolves this morning and
into the early afternoon will play a role in the amount of
instability and how much the atmosphere recovers for afternoon
and evening convection.

Previous Discussion Follows:
Some notable changes were observed in the latest guidance early
this morning and it is mainly to delay convective initiation
this afternoon and push back the timing of the frontal passage
until mid evening. The severe risk also has shifted more east to
areas along and east of I-95 and east of Rt 15 in northern MD.
Latest CAMs this morning show several broken short line
segments including bows developing across the northern neck of
VA lifting NE into southern MD. Other short line segments are
seeing on the reflectivity products over north central MD into
southern PA. The primary threat remains damaging winds due to
strengthening wind fields and moderate instability (~1500 J/kg),
but a couple of tornadoes and isold large hail are also
possible. Severe risk should diminish quickly after 00Z and be
over completely by 02Z Tue.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Scattered to numerous instability showers are expected Tue and
Wed afternoons as additional shortwave energy rounding the base
of the upper trough axis moves across the region. Shower
activity on Tue may not produce any lightning at all, but has
better chance of generating lightning on Wed due to higher CAPE
values and steeper mid-level lapse rates/cooler temps aloft.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Deep upper troughing will move overhead during the day
Thursday. Skies should start out mostly sunny, but some fair
weather clouds may form in response to daytime heating during
the afternoon. A few sprinkles or a brief light shower can`t be
ruled out either, but most locations should remain dry. High
temperatures are forecast to reach into the upper 60s to mid
70s, with dewpoints only in the mid 40s.

We`ll remain under the influence of upper troughing through the day
Friday, but the trough axis will start to progress off to our east
during the afternoon hours. This will result in another day of below
normal temperatures within northwesterly flow. Sunny skies are
expected, with high temperatures generally in the upper 60s to mid
70s. High pressure will build in from the Great Lakes Friday night.
With clear skies, light to calm winds, and dewpoints only in the low
to mid 40s, it will be a chilly first night of June, with low
temperatures dropping back into the 40s to near 50 for most.

Narrow upper ridging will build overhead next weekend, before the
flow flattens out and turns more zonal in nature early next week.
High pressure at the surface will move overhead Saturday morning,
before progressing offshore later Saturday into Sunday. As this
happens, a slight warming trend in temperatures will occur. Highs on
Saturday are expected to reach into the mid-upper 70s, with upper
70s to lower 80s in the forecast for Sunday. Conditions are expected
to remain predominantly dry this upcoming weekend, but a stray
afternoon shower or thunderstorm can`t be ruled out on Sunday.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
Showers and thunderstorms are likely to impact the main
terminals this afternoon. The highest risk is at BWI and DCA
with lesser chance at IAD and MRB. CHO appears to have the least
risk of experiencing thunderstorms. Severe wind gusts are
possible particularly at BWI and DCA. Threat should end by 00Z
tonight.

Prevailing VFR conditions and northwesterly winds are expected on
both Thursday and Friday.

&&

.MARINE...
SCA conditions expected today through tonight due to gradient
winds. Special Marine Warnings are also likely to be required
for thunderstorm winds greater than 33 kt.

Sub-SCA northwesterly winds are expected on both Thursday and
Friday.

&

.TIDES/COASTAL FLOODING...

With increasing south/southeast flow, there will be a higher
chance of minor flooding with this morning`s high tide. Straits
Point, Annapolis, and DC SW Waterfront will be most
susceptible. Westerly winds behind a cold front will lead to
decreasing anomalies through the middle of the week.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
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DC...Coastal Flood Advisory until 1 PM EDT this afternoon for
     DCZ001.
MD...Coastal Flood Advisory until 1 PM EDT this afternoon for
     MDZ014.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ530-
     535-536-538.
     Small Craft Advisory from 11 AM to 6 PM EDT Tuesday for ANZ530-
     531-539.
     Small Craft Advisory until 3 AM EDT Tuesday for ANZ531>534-537-
     539>543.
-- End Changed Discussion --

&&

$$

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