579
FXUS61 KAKQ 051012
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
612 AM EDT Sun May 5 2024

.SYNOPSIS...
Off and on showers are expected to continue through Sunday night.
Summerlike conditions return to the area for next week with
daily chances of showers and storms.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 320 AM EDT Sunday...

Early morning wx analysis indicates Friday`s backdoor cold
front now pushing back N as a warm front, draped across the
southeastern portion of the FA as of 3am. This is evident not
only from the winds having turned to the SE, but also the
temperature gradient across the area this morning. Latest obs
show upper 60s in the SE with dewpoints also in the 60s and low
50s in the NW for both temps and dewpoints. As the front
continues northward, temps will remain stable in the SE and rise
a few degrees elsewhere. Aloft, a weak shortwave is traveling
across the region, aiding in the continuation of showers. Latest
radar shows widespread, light precip W of I-95 and isolated-
scattered showers elsewhere. Heavier showers near the RIC metro
have dropped 1.0-1.5" of rain tonight, spurring a Flood Advisory
just south of RIC. These heavier showers have weakened, though,
and moved to the ENE.

Shortwave energy within the SW flow aloft as well as the front
advancing N will lead to additional rounds of showers and
tstorms today. Expect the highest coverage will stay in the
piedmont through the morning, then expand to all areas W of the
bay (~70% PoP) this afternoon. Coverage is then expected to
decrease later in the evening and into tonight as the main axis
of precip progresses E. Chnc PoPs then continue E of I-95
through the night. Instability of 600-700 J/KG (mean HREF SCAPE)
means there will be a decent chance for thunder. Regarding QPF,
expecting widespread 0.25-0.5" with higher amounts of 1.0-1.5"
within heavier showers/storms. Highs today will be in the mid-
upper 70s in the SE and upper 60s-low 70s elsewhere. Remaining
mild overnight with lows in the mid-60s.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 350 AM EDT Sunday...

Key messages:

- Continued unsettled pattern with on and off rain to start the week

- A warming trend expected with above normal temps and humid conditions


Mon and Tues mark the start of a summer-like pattern that will
persist through the week. Multiple rounds of shortwaves in the
(fairly weak) SW flow aloft plus a lee trough will lead to off and
on shower/storm chances. These will likely follow a generally
diurnal pattern with the best chances in the afternoon through late
evening. Temps climb into the low 80s on Monday with dewpoints as
high as the upper 60s. HREF mean CAPE shows values over 1000 J/KG,
but shear will be weak. Therefore, severe weather is not expected
outside of a strong storm or two. Highest coverage in precip on Mon
looks to be across the south (roughly S of US-460) during the
afternoon hours as of latest guidance. Tuesday is less certain, as
models are still showing some disagreement regarding coverage and
timing of precip. Highs will be in the mid 80s across the south
of low 80s in the north. Lows both nights will be in the mid-
upper 60s.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 350 AM EDT Sunday...

Key messages:

-A summer-like pattern will bring unsettled conditions and
 above-normal temps Wednesday through Friday.

-There is the potential for severe weather mid to late week.

An unsettled, summertime continues through the rest of the week.
A ridge aloft starts to break down Wed. The GFS and ECMWF both
suggest stronger 500mb flow of up to 50 kt by Wed-Thurs.
Additionally, several waves of weak shortwave energy will pass
over the area. As of latest guidance, the strongest of these
looks to pass through Thu ahead of an UL trough dropping into
the Great Lakes. A stronger system (i.e. cold front) will then
cross the area Thu night into Fri. These features along with
plentiful daytime heating/instability will allow for daily
rounds of showers/tstms. Will be monitoring this time period for
severe weather given the support aloft and steep mid-level
lapse rates. The CSU Machine Learning Probabilities have picked
up on the aforementioned parameter space and suggest at least a
slight risk for severe weather Thu for the entire area. Mainly
dry weather will return for Sat. Highs will be in the mid 80s
to lower 90s Wed and Thu, in the upper 70s to lower 80s Fri, and
in the lower to mid 70s Sat.

&&

.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
As of 145 AM EDT Sunday...

IFR CIGs still prevail at RIC late tonight with MVFR/VFR at
SBY/ORF/PHF/ECG. The backdoor cold front that crossed the area
Friday will slowly lift back north as a warm front through the
period. CIGs improve to MVFR (with occasional periods of VFR)
as winds become SE-SSE after the front moves north of a given
terminal. It looks like IFR CIGs likely hang on until late
morning at RIC. In addition, showers will once again overspread
RIC tonight. Showers are likely at all terminals on Sun, with
isolated- scattered tstms possible during the aftn/evening.

Outlook...Sub-VFR conditions are expected at times from Sunday night-
Monday, due to an unsettled weather pattern. Sunday night should be
mostly dry, but more tstms are possible Mon aftn-late Mon evening.
A warmer, more summerlike pattern returns Tue through Thu, with
chances for storms each aftn/evening.

&&

.MARINE...
As of 320 AM EDT Sunday...

Key Message:

- All Small Craft Advisories have been discontinued.

Strong sfc high pressure (>1030mb) is centered across Atlantic
Canada early this morning, with a stationary front in vicinity
of the NC Outer Banks slowly pushing N. E-SE winds prevail, but
the wind speeds have generally been under-performing over the
past 12 hrs and as such, have decided to cancel all remaining
SCA headlines. Conditions today will still be less than ideal
for boating as SE winds average 10-15 kt with gusts to ~20 kt
and waves of 2-3 ft in the Bay and 1-2 ft in the rivers. Seas
are 3-4ft.

The stationary front will continue to lift back N as a warm
front later today, with winds becoming more from the S at
10-15 kt tonight, and then to the SSW by Monday. Winds will
average ~10 kt with gusts less than 20 kt through the week so outside
of any tstms, conditions will be sub-SCA. The winds may increase
a bit Thu- Fri as the pressure gradient tightens with the
approach of a stronger cold front.

&&

.TIDES/COASTAL FLOODING...
As of 600 AM EDT Sunday...

Key Messages:

- Coastal Flood Advisory remains in effect for the northern Neck
  through late tonight/early Monday for minor flooding.

- A new Coastal Flood Advisory is in effect for the high tide
  cycle late tonight/early Monday for the bayside of the
  Maryland eastern shore.

Ebb tide currents have been stronger over the past 18-24 hrs,
leading to a slight lowering of tidal departures in the Bay and
tidal rivers (departures are now mainly +1.0 to +1.25 ft above
astro tide). The upcoming high tide cycle later this
morning/early this aftn will likely fall short of Minor Flood
thresholds given the latest obs and trends, with the following
cycle late tonight/early Monday morning expected to reach into
Minor flood thresholds. This is due to a few extra tenths of a
foot of surge (from SSE winds) in tandem with astro tides that
will also be a few tenths higher during this timeframe. Coastal
Flood Advisories are in effect to cover this period (for the
northern Neck the Advisory is also in effect for 1st tide today
given the product was already in effect). Water levels are
expected to drop off by ~0.5 ft later Monday as winds shift to
the SW and water flushes out of the mouth of the Bay. Some
nuisance to localized low- end minor flooding will still be
possible with the higher diurnal astro tides late Mon
night/early Tue AM and again late Tue night/early Wed AM.


&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...Coastal Flood Advisory from 9 PM this evening to 6 AM EDT
     Monday for MDZ021>023.
NC...None.
VA...Coastal Flood Advisory until 4 AM EDT Monday for VAZ075>078.
MARINE...None.

&&

$$

SYNOPSIS...TMG
NEAR TERM...AM
SHORT TERM...AM/TMG
LONG TERM...AM/TMG
AVIATION...AM/ERI
MARINE...AJZ/LKB
TIDES/COASTAL FLOODING...AKQ