Marine Weather Net

Tidal Potomac from Indian Head to Cobb Island MD Marine Forecast




5 - 10


5 - 10



The Marine Weather Forecast In Detail:
ANZ536 Forecast Issued: 437 PM EDT Tue Jun 22 2021

Rest Of This Afternoon...N Winds 10 Kt With Gusts To 20 Kt. Waves 1 Ft. Scattered Showers.
Tonight...N Winds 5 To 10 Kt With Gusts To 20 Kt. Waves 1 Ft.
Wed...Ne Winds 5 To 10 Kt. Waves 1 Ft.
Wed Night...E Winds Around 5 Kt. Waves 1 Ft.
Thu...E Winds Around 5 Kt. Waves 1 Ft.
Thu Night...E Winds Around 5 Kt. Waves 1 Ft.
Fri...Se Winds 5 To 10 Kt. Waves 1 Ft.
Sat...S Winds 5 To 10 Kt. Waves 1 Ft.
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Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
259pm EDT Tuesday Jun 22 2021

A cold front will exit the region this evening. High pressure will build into our region on Wednesday and remain nearby through the end of this week. A cold front will remain situated off to the west this weekend through early next week leading to continued chances for precipitation.

Near Term - Until 6am Wednesday Morning
A cold front is slowly moving off to the southeast of our region this afternoon. The anafrontal nature of the cold front has led to continued showers along with isolated thunderstorms impacting parts of our region behind the front. The rain has for the most part moved east of the Blue Ridge Mountains with the majority of precipitation focused along and east of the I-95 corridor. As the front continues to shift further away from our region, the precipitation will start to diminish from west to east. Current timing of the showers along with most recent high Res Guidance suggests that the threat for showers and storms should end after 21Z this afternoon. Areas well behind the frontal passage are starting to see the low overcast clouds starting to break up and become broken to scattered in nature. The daily high temperatures likely occurred earlier this morning with highs peaking in the low to mid 70s. Currently, temperatures are hovering in the low to mid 60s with near a saturated atmosphere.

As the front continues to pull away from the region, winds are expected to become more northwesterly leading to cooler and drier air being advected into our region. Skies will become mostly clear overnight into Wednesday morning with lows dropping down into the mid to upper 40s west of the Blue ridge and down into the 50s along and east of the I-95 corridor.

Short Term - 6am Wednesday Morning Through Thursday Night
High pressure will build into our region from the west on Wednesday as weak upper level ridging moves overhead. Dry conditions are expected through Thursday with temperatures peaking in the 70s on Wednesday. Overnight lows on Wednesday will be cooler in the 50s as winds remain light and skies mostly clear.

High pressure will begin to shift off-shore late Wednesday and into Thursday. Models suggest that the high will wedge back over our region on Thursday which will lead to winds becoming more east to southeasterly. The onshore flow will likely lead to increasing moisture and cloud cover on Thursday along with continued mild highs in the lower 80s. The continued onshore flow will keep overnight lows elevated on Thursday in the mid to upper 50s to lower 60s.

Long Term - Friday Through Monday
A fairly stagnant upper-level pattern is setting up for the long term period. A strong upper-ridge over the Pacific NW will stay locked in place, with a trough over the center of the country, and finally another weaker upper ridge over the western Atlantic. At the surface, Bermuda high pressure remain locked in, bringing warm and moist air back into the region Friday through Monday. Highs Friday only reach the low to mid 80s as there may still be an easterly component to the winds before we really turn more southwesterly. However, as the return flow really kicks in Sat-Mon, temps rise into the mid-upper 80s each day, along with dew points in the mid 60s to low 70s. As a result of this warmth and moisture, and the lack of much upper-level flow, thunderstorms could develop each afternoon along the Bay Breeze and terrain circulation and be rather slow moving. Overnight lows each night only dip into the upper 60s to low 70s.

SCA (Small Craft Advisory) level winds are expected through the overnight periods due to channeling northwest flow. SubSCA (Small Craft Advisory) conditions expected Wednesday and Thursday.

Winds remain below SCA (Small Craft Advisory) criteria Friday through Sunday. However, could see some afternoon showers and storms each afternoon that could potentially lead to more short fused wind events.

Tides / Coastal Flooding
Water levels have gradually begun to drop off in response to the post-frontal north-northwesterlies. Tidal anomalies should remain on the lower side the next 24 hours before rising by mid-week from light easterly flow. A few sites move into the Action Stage early Thursday with perhaps further rises late in the week given southerly warm advection.

NOAA Baltimore MD/Washington DC Office: Watches - Warnings - Advisories
DC...None. MD...None. VA...None. WV...None.
Small Craft Advisory until 8am EDT Wednesday for ANZ531>534- 537-539>543. Small Craft Advisory until 8pm EDT this evening for ANZ530- 535-536-538.