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ANZ535 Tidal Potomac From Key Bridge To Indian Head- 1232 Am Est Thu Nov 30 2023
Overnight..SW winds 5 kt. Waves less than 1 ft.
Thu..S winds 5 to 10 kt. Waves 1 ft.
Thu night..S winds 5 to 10 kt. Waves 1 ft.
Fri..S winds 5 to 10 kt. Waves 1 ft. Showers likely.
Fri night..SW winds 5 to 10 kt. Waves 1 ft. A chance of showers.
Sat..SW winds 5 kt. Waves less than 1 ft.
Sat night..NW winds 5 kt. Waves less than 1 ft. A chance of showers.
Sun..N winds 5 to 10 kt...becoming E in the afternoon, then becoming w. Waves 1 ft. A chance of showers.
Mon..NW winds 10 to 15 kt. Waves 1 ft. A chance of showers through the day.

ANZ500 1232 Am Est Thu Nov 30 2023
Synopsis for the tidal potomac and md portion of the chesapeake bay..
high pressure will continue to slide offshore through Thursday. Another frontal system and area of low pressure push through the area Friday into Saturday. A stronger frontal system looks to cross the waters early next week. Small craft advisories possible Thursday night and Friday night.

FXUS61 KLWX 300155 AFDLWX

Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 855 PM EST Wed Nov 29 2023

SYNOPSIS
High pressure over the region slides offshore on Thursday. Warming temperatures through late week. Rain chances return Friday as an area of low pressure and it's associated cold front push east from the Ohio River Valley. Additional precipitation chances are expected through the weekend into early next week.

NEAR TERM /UNTIL 6 AM THURSDAY MORNING/
Surface high pressure is centered across the southeastern states tonight. The area of mid level clouds associated with a perturbation in WNW flow aloft will continue to push east and exit the area by midnight. Some cirrus will enter the area later tonight.

Low temperatures may exhibit wide ranges across short distances as forecast soundings show a very shallow but sharp nocturnal surface inversion with the antecedent dry airmass (dew points in the teens). A low level jet above the inversion may limit temperature falls for a time. These winds will relax the second half of the night, but will likely be strong enough to prevent full radiational cooling. The other wild card is the cirrus, which some guidance indicates could be thicker west of I-81. In the forecast database, have trended toward cooler guidance in valleys/rural areas along and east of I-81 and brought up temperatures a pinch on the ridges and urban areas. Practically, that translates to the clear/cold valleys dropping to near/below 20, most areas ranging through the 20s, and the cities, bayshore, and some ridges in the 30s.

SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/
High pressure slides offshore Thursday as dry conditions persist.
Warm advection brings afternoon temps back to the low to mid 50s across most of the area. Cloud cover increases Thursday night as a strong shortwave through approaches from the Mid-South. Not as cold Thursday night with lows in the low to mid 30s.

As the shortwave trough crosses the region Friday, there could be periods of showers Friday afternoon into Friday evening. However, ample dry air remains at the surface, and it will take some time to saturate the low-levels. Any rain is likely to be light and short duration given most of the energy associated with this system will remain north of the area. Highs in the upper 40s to low 50s, with milder temps Friday night in the upper 30s to mid 40s.

LONG TERM /SATURDAY THROUGH WEDNESDAY/
Broad troughing will be centered over the center of the CONUS on Saturday, placing us in southwesterly flow aloft. Multiple disturbances will rotate through this broader scale trough as it builds eastward this weekend. Meanwhile, large scale ridging will become established along the West Coast. As these various disturbances rotate through, we'll have an extended period of cloudy conditions this weekend into early next week, along with occasional chances for showers. As of now, the greatest chance for some showers appears to be Sunday into Monday.

Eventually a cold front will move through at the surface, somewhere in the Monday to Tuesday timeframe, with colder air filtering back into the area behind the front. Chances for precipitation will decrease within downslope northwesterly flow to the east of the mountains, but chances for upslope showers will linger through the middle of the week to the west of the Allegheny Front within upslope flow. By later Monday into Tuesday, the precipitation will likely be in the form of snow to the west of the Allegheny Front, with accumulating snow possible.

AVIATION /02Z THURSDAY THROUGH MONDAY/
VFR conditions are expected through Thursday night as high pressure moves over, then east of the area. Low level wind shear (or at least turbulence) may briefly and locally near the critical threshold of 30 kt tonight due to a low level jet above a sharp nocturnal surface inversion, but that value appears unlikely to affect the TAF sites. Southwest to south winds prevail during the afternoon/evening each day, with occasional gusts to 15KT possible at the TAF sites.

An area of low pressure will move just north of the area Friday into Friday night, possibly bringing a period of sub-VFR conditions to some of the TAF sites. Rain showers likely on Friday, though most are expected to be light. Southerly winds continue on Friday, gusting to 15-20KT in the afternoon and evening.

Sub-VFR conditions may be possible at times on both Saturday and Sunday. Winds will be out of the south to southwest on Saturday, and then light and variable on Sunday.

MARINE
High pressure over the region tonight will slide offshore on Thursday, as south to southwest winds prevail through Thursday night. A low level jet is resulting in an increase in southwest winds this evening. SCAs are in effect for all the waters through midnight, with the bay/wider waters continuing until 6 AM Thursday morning. So far this evening, it appears the narrower inland waters have decoupled sufficiently to prevent the stronger winds from mixing to the surface, so this advisory may be cancelled early.

Southerly channeling Thursday evening could result in the need for SCAs for portions of the waters, mostly in the open bay. An area of low pressure will move north of the area on Friday, with another brief increase in winds possible Friday evening.

Sub-SCA southerly winds are expected on Saturday. Light and variable winds are expected on Sunday.

LWX WATCHES/WARNINGS/ADVISORIES
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 6 AM EST Thursday for ANZ530>534- 537-539>541-543.
Small Craft Advisory until midnight EST tonight for ANZ535-536- 538-542.

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Glymont
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Thu -- 03:35 AM EST     -0.06 feet Low Tide
Thu -- 07:06 AM EST     Sunrise
Thu -- 09:11 AM EST     1.66 feet High Tide
Thu -- 10:26 AM EST     Moonset
Thu -- 03:23 PM EST     0.00 feet Low Tide
Thu -- 04:47 PM EST     Sunset
Thu -- 07:34 PM EST     Moonrise
Thu -- 09:21 PM EST     1.89 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION

Glymont, Maryland, Tide feet

Deep Point
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Thu -- 03:10 AM EST     -0.05 feet Low Tide
Thu -- 07:06 AM EST     Sunrise
Thu -- 08:46 AM EST     1.48 feet High Tide
Thu -- 10:26 AM EST     Moonset
Thu -- 02:58 PM EST     0.00 feet Low Tide
Thu -- 04:48 PM EST     Sunset
Thu -- 07:35 PM EST     Moonrise
Thu -- 08:56 PM EST     1.69 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION

Deep Point, Mattawoman Creek, Maryland, Tide feet

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