Sunrise 6:10 AM   Sunset 8:02 PM Moonrise 12:59 AM   Moonset 10:16 AM

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ANZ535 Tidal Potomac From Key Bridge To Indian Head- 1034 Am Edt Tue Apr 30 2024
.small craft advisory in effect through this evening - .
Rest of today - SW winds 10 kt with gusts to 20 kt. Waves 1 ft. Tonight - SW winds 5 to 10 kt. Gusts up to 20 kt early in the evening. Waves 1 ft. A chance of showers. Wed - NW winds 5 kt. Waves less than 1 ft. Wed night - E winds around 5 kt. Waves 1 ft. Thu - SE winds around 5 kt. Waves 1 ft. Thu night - SE winds 5 kt. Waves less than 1 ft. Fri - E winds 5 to 10 kt. Waves 1 ft. A chance of showers through the night. Sat - SE winds 10 kt. Waves 1 ft. Showers likely.

ANZ500 1034 Am Edt Tue Apr 30 2024
Synopsis for the tidal potomac and md portion of the chesapeake bay -
a cold front crosses the waters this evening into Wednesday morning bringing chances for showers and Thunderstorms. High pressure briefly returns Thursday before another slow moving front crosses the local waters over the weekend. Small craft advisories may be needed on Friday and Saturday.

FXUS61 KLWX 301357 AFDLWX

Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 957 AM EDT Tue Apr 30 2024

SYNOPSIS
A cold front will slowly push through the region this afternoon and evening bringing scattered showers and thunderstorms. A few showers linger Wednesday morning with dry high pressure settling back in for the afternoon. Warm and dry conditions continue Thursday before shower and thunderstorm chances return with another front Friday into the start of the weekend.

NEAR TERM /THROUGH TONIGHT/
Subtle relief from the heat in the form of a cold front/lee trough is expected to pass through the region later this afternoon and evening. The front is evident on radar with a band of precipitation extending from Lake Erie south along the Ohio River into eastern Kentucky. This area of precipitation will continue to slowly move east this morning allowing for an uptick in cloud cover across our region heading into early to mid-afternoon. As for precipitation chances, 6z/12z hi-res CAM guidance continues to show varying differences in regards to timing and coverage. Most of the guidance shows the leading edge of the precipitation entering our western most counties (i.e Garrett Co. MD and Pendleton/Hardy Co. WV ) around 2- 4pm with isolated showers along the higher ridgetops of the Blue Ridge/Alleghenies during this same timing window. The main band of shower and thunderstorm activity will work into the I-81/Blue Ridge corridor between 5-8pm before shifting toward the metros and dissipating after sunset. As for the threat of severe weather, it remains low, but not zero. Instability will remain fairly low on the order of 500-1200 j/kg with 0-6km bulk effective shear values running 20-30 kts. Both SPC, CSU Machine Learning, and CIPS analogue products continue to point to a very low probability of severe weather. Even with that said, one or two storms could become strong given the antecedent conditions especially west of the Blue Ridge. Biggest threats with any storms this afternoon and evenings looks to be wind gusts 40-50 mph, frequent lightning, and locally heavy rainfall (PWATS running 0.75-1.25 inches).

High temperatures today will push back into the mid to upper 80s with 70s over the mountains/near the bay. Metro areas could flirt with 90 degrees. Heat index values will remain below 95 degrees given the fact that dewpoints will remain in the mid to upper 50s and low 60s.

Storms move out of the area before midnight, with a slight chance of showers lingering through early Wednesday morning as the front moves to our south and east. Lows tonight will fall back into the upper 50s and low 60s with areas of patchy fog that due see the rain.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/
By Wednesday morning, the aforementioned cold front will be lifting northward as an upper level trough pivots over the area. This will allow for precipitation chances to linger throughout the morning.
Recent model guidance has trended drier for Wednesday, with conditions expected to dry out areawide in the afternoon. Surface low pressure near the Carolinas make so an isolated rain shower cannot be ruled out in the southernmost portions of the area.
However, chances for this remain low as dry air aloft filters into the area.

Dry conditions continue on Thursday as high pressure builds in over the area. A moisture starved cold front will linger over the forecast area, but no precipitation is expected with this. High temperatures each day will be in the 70s to mid 80s with overnight lows dipping into the 50s to low 60s each night.

LONG TERM /FRIDAY THROUGH MONDAY/
Large scale ridge will start breaking down Saturday as successive mid-level perturbations move across the Mid-Atlantic region during the second half of the weekend. Moisture will pool along a decaying/weakening frontal zone Saturday to bring the threat of showers. This frontal zone will be slow to exit the area with the risk of showers persisting through Sunday. Given the slow progression of this front, isolated heavy rain totals exceeding an inch are possible which may cause isolated flooding in the more vulnerable urban areas. The lack of instability suggest any rainfall should be manageable. By Monday, enough dry air appears to make it into the area and the frontal zone dissipates to lower PoP chances allowing sunshine to bring temperatures back up.

AVIATION /14Z TUESDAY THROUGH SATURDAY/
VFR conditions are expected this morning through the early afternoon, ahead of any precipitation expected later today. A cold front moving over the area will bring scattered showers and thunderstorms to all terminals this evening and into the late evening. Some storms may be strong, possibly producing winds gusts of 35 knots or greater, frequent lightning strikes, and heavy rainfall leading to reduced visibilities. Shower and thunderstorms chances move out of all terminals between 03-04 UTC with the exceptions being CHO where conditions dry out earlier around 01 UTC.

Outside of showers and thunderstorms, VFR conditions are expected.
Southwesterly winds today will shift to northwesterly winds on Wednesday. Winds gust between 10-15 knots this afternoon with winds gusting up to 20 knots at DCA. Winds diminish overnight before remaining light on Wednesday, blowing between 5-10 knots. VFR conditions continue on Thursday as high pressure builds in over the area.

Showers are likely on Saturday. Cig restrictions are possible Saturday.

MARINE
A cold front will cross the waters this afternoon and into the overnight, leading to increased chances of showers and thunderstorms. A SCA is in effect for this afternoon and into this evening for southwest winds 10 to 15 knots with gusts up to 20 knots expected. During thunderstorms, higher wind gusts of 35 knots or greater are possible along with lightning. Special Marine Warnings may be required as showers and thunderstorms cross the waters.

By Wednesday morning, showers and thunderstorms will have moved away from the waters. Winds shift to the northwest an are expected to stay below SCA criteria. Winds shift to the south on Thursday, but continue to remain below SCA criteria.

Small Craft Advisory conditions likely Friday through the weekend. Showers appear likely over the weekend, but the threat of thunderstorms remains low.

CLIMATE
Below is a list of record high temperatures for today, April 30th.

Apr 30th Climate Site Record High Forecast High Washington-National (DCA) 92F (1942+) 87F Washington-Dulles (IAD) 86F (2017+) 85F Baltimore (BWI) 92F (1910) 87F Martinsburg (MRB) 91F (1974+) 84F

+ denotes that multiple years reached this value, but the depicted year is the most recent

LWX WATCHES/WARNINGS/ADVISORIES
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory until midnight EDT tonight for ANZ530>543.

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Mount Vernon
Click for Map
Tue -- 12:52 AM EDT     2.19 feet High Tide
Tue -- 01:58 AM EDT     Moonrise
Tue -- 06:11 AM EDT     Sunrise
Tue -- 07:08 AM EDT     0.52 feet Low Tide
Tue -- 11:16 AM EDT     Moonset
Tue -- 12:58 PM EDT     2.50 feet High Tide
Tue -- 08:00 PM EDT     Sunset
Tue -- 08:13 PM EDT     0.45 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION

Mount Vernon, Virginia, Tide feet

Chain Bridge
Click for Map
Tue -- 01:44 AM EDT     2.85 feet High Tide
Tue -- 01:59 AM EDT     Moonrise
Tue -- 06:11 AM EDT     Sunrise
Tue -- 08:06 AM EDT     0.64 feet Low Tide
Tue -- 11:15 AM EDT     Moonset
Tue -- 01:50 PM EDT     3.26 feet High Tide
Tue -- 08:00 PM EDT     Sunset
Tue -- 09:11 PM EDT     0.55 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION

Chain Bridge, D.C., Tide feet

Full Color Weather Map

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Sterling, VA,