Marine Weather and Tide Forecast for Kings Park, VA

NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/
01Z radar imagery shows a convective system across Ohio, Kentucky, and West Virginia moving east at a decent rate of speed. It is starting to become less organized with continued cells popping up along the cold pool of the system, but the cold pool is slowly outracing the system. Most guidance has this system moving into the western portions of the area by about midnight, with it slowly dissipating by the time it makes it towards the US-15 corridor. Cannot rule out a rogue severe gust, but most thermodynamics are starting to diminish givin loss of diurnal heating
Previous discussion follows

For the remainder of the overnight hours, a continued warm advection regime favors a very mild night with lows in the low/mid 60s (50s across mountain locales). This is easily 10 to 20 degrees above late April climatology. Winds do gradually shift to southwest to westerly as a cold front slowly pushes through. Aside from some lingering showers along the Alleghenies, most shower activity should abate through the night.

SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/
The aforementioned cold front is expected to continue its south and eastward trajectory through the day. This yields a shift to mainly north to northwesterly flow. Although temperatures should remain plenty warm with highs in the upper 70s to low 80s, this does come with a drop in dew points. North of this boundary, dew points may fall into the 40s, while low/mid 60s are more commonplace off to the south in the warm sector. After a mainly dry start to the day, some overrunning showers may impact those south of I-66. Depending on the coverage of this activity, these could inhibit some of the expected warming.
Overall skies should consist of a mix of sun and clouds. Any threat for showers is expected to gradually diminish into Wednesday night. Forecast lows will be a bit cooler owing to the drier air mass. Under a light northeast to easterly wind, low temperatures drop into the 50s with a few low 60s possible along I-64.

Thursday brings a return of the frontal zone that had moved to the south the preceding day. Most guidance favor bringing this system poleward as a warm front. This yields a return to mainly south to southeasterly winds, increasing dew points, and more instability to work with. Forecast highs on Thursday are in the upper 70s to low 80s, but with some ensemble spread noted. This is likely due to the timing of upstream showers and thunderstorms that begin to impact the region. Models show a decent shortwave tracking in from the Ohio and Tennessee Valleys during the evening hours. The mid-level flow is a bit stronger as well, generally averaging around 35 to 45 knots.
This carries a non-zero threat for severe thunderstorms, but details remain nebulous at this time. A mild air mass persists into the night ahead of the next cold front. Lows are forecast to be in the low/mid 60s, with mid/upper 50s back over the higher terrain.

LONG TERM /FRIDAY THROUGH TUESDAY/
A low pressure system will move northeast across the eastern Great Lakes to the north of New England on Friday into Friday night. A leeside trough of low pressure will extend from this low and become aligned with the leeside ridgeline of the Blue Ridge during the same timeframe. This trough will become the focal zone of developing showers and isolated thunderstorms Friday afternoon into Friday evening. Some of this activity could make its way across the metros and toward the Chesapeake Bay region. A cold front, also extending from the low pressure system, will slide into the Appalachians by Friday night. A mid- level low pressure system will drop southeastward from the Upper Midwest U.S. into our western zones as well. The combination of the lift from the surface cold front and the mid-level support could ignite more showers and thunderstorms Friday night into Saturday morning. Considering this additional convection would more likely form overnight into early the next day, instability could be minimal with a little wind shear. Therefore, convection Friday night and early Saturday may not be as strong as Friday afternoon and evening. High temperatures Friday should be on the warm side with temperatures reaching the middle 80s. Friday night's lows will only drop into the lower 60s.

Throughout the day Saturday into Saturday evening, showers and any thunderstorms will gradually end from west to east. The main low pressure system well to the northeast and its associated cold front, along with its mid-level support, will be progressive in moving eastward. High pressure will build in from the west later Saturday and through the day on Sunday into Sunday night. Highs Saturday should be cooler but reasonably close to average for early May.
Temperatures will top out in the lower to middle 70s Saturday.
Saturday night's lows will drop into the upper 40s as cooler and drier air work into the region. Sunday's highs could be cooler than Saturday with highs in the upper 60s, followed by lows near 50.

While high pressure should be the flavor of the day on Monday, bringing seasonable air and dry conditions to the CWA, models tend to think there may be a backdoor cold front arrive from the north or a retrograding low pressure system arriving from the northeast or east. If this is the case, then our temperatures will be cooler Monday and our rain chances will be chance at least in some places.
For now, high temperatures seem to be near 70.

AVIATION /01Z WEDNESDAY THROUGH SUNDAY/
VFR conditions will persist through the evening, with gusts up to 20 kts out of the S to SW. Looking upstream, a complex of thunderstorms, currently located over Ohio, West Virginia, and Kentucky, will eventually push into our region much later this evening. Low confidence of rain making it to MRB, but even that is uncertain. Cannot rule out some showers get to DCA/BWI/MTN.

Thereafter, a cold front moves through later tonight which yields a gradual shift to southwest to westerly winds. VFR conditions are expected on Wednesday as this boundary continues to sink southward. Winds should be mainly northerly through the day before shifting to a light northeast to easterly by Wednesday night. Some showers are possible south of I-66 (i.e., near KCHO) which could warrant a few brief restrictions.
Eventually this frontal zone returns northward as a warm front on Thursday which brings back southerly flow and thunderstorm chances.

VFR conditions Friday. MVFR conditions more probable at MTN, BWI, DCA and IAD with showers or thunderstorms along a leeside trough late Friday into Friday night. MVFR to IFR conditions at all terminals possible with showers and thunderstorms Saturday. VFR conditions returning Saturday night. Winds southwest 10 to 15 knots gusts 20 knots Friday into Friday evening. Winds southwest becoming northwest 5 to 15 knots Saturday into Saturday evening.

MARINE
Small Craft Advisories remain in effect for all marine locations through midnight as a strong southerly flow developes as high pressure pulls offshore. Advisories linger through daybreak across the southern waters.

A cold front moves through later tonight before sagging off to the south on Wednesday, yielding a shift to northerly winds.
This front will then lift northward as a warm front on Thursday which yields a shift to southerly flow and more thunderstorm chances. In response, winds increase on Thursday which may warrant a return to SCA conditions.

Small craft advisories likely Friday and Friday evening. Small craft advisories possible Saturday. Winds southwest 10 to 15 knots gusts 20 knots Friday and Friday evening. Winds southwest becoming northwest 10 to 15 knots Saturday into Saturday evening.

TIDES/COASTAL FLOODING
Given a modest uptick in southerly flow, some of the typically higher guidance (SFAS, CBOFS) approaches minor flood stage at vulnerable sites like Annapolis during the astronomically higher morning tides through Wednesday. However, given the brevity of the southerly flow and its relatively low magnitude, feel that flooding seems unlikely at this time.

LWX WATCHES/WARNINGS/ADVISORIES
DC...None.
MD...Small Craft Advisory until midnight EDT tonight for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory until midnight EDT tonight for ANZ530>532- 535-536-538>540-542.
Small Craft Advisory until 6 AM EDT Wednesday for ANZ533-534- 537-541-543.