Choptank River to Cambridge MD and the Little Choptank River Marine Forecast
|This Afternoon...N Winds 15 Kt With Gusts To 20 Kt. Waves 2 Ft. Isolated Showers.|
|Tonight...N Winds 10 To 15 Kt With Gusts To 20 Kt. Waves 2 Ft.|
|Sat...N Winds 10 To 15 Kt With Gusts To 20 Kt. Waves 2 Ft.|
|Sat Night...N Winds 10 Kt With Gusts To 20 Kt. Waves 1 Ft.|
|Sun...N Winds 10 To 15 Kt. Waves 1 To 2 Ft.|
|Sun Night...N Winds 5 To 10 Kt. Waves 1 Ft.|
|Mon...N Winds 10 To 15 Kt...Becoming E 5 To 10 Kt. Waves 1 Ft.|
|Tue...Ne Winds 5 To 10 Kt. Waves 1 Ft.|
| Area Forecast Discussion|
National Weather Service Baltimore MD/Washington DC
945am EDT Fri September 29 2023
An inverted surface trough will remain along the Atlantic coast through tonight. Meanwhile, an upper level trough will cross the area tonight. The trough will push offshore for the start of the weekend as upper level ridging aloft and high pressure builds back into the region. Strong upper-level ridging remains locked in through at least the middle of next week.
Near Term - Through Tonight
An upper-level trough will move into the area from the west this afternoon and evening before moving off to the east later tonight. Low pressure offshore will continue to move off to the northeast today while surface high pressure remains to the north.
An onshore flow will turn northerly today, but low-level moisture will continue to wrap around the low over the Atlantic, resulting in low clouds trapped underneath the subsidence inversion. The low clouds will mix out (have already in some instances) across central Virginia into the Allegheny and Potomac Highlands where low-level moisture is not quite as deep. A few showers and perhaps even a thunderstorm are possible this afternoon across these areas due to limited instability that will develop from the sunshine and colder air aloft associated with the upper-level trough. A few showers are also possible across northeastern MD as moisture wraps around low pressure offshore. Areas of drizzle with the low clouds late this morning should gradually dissipate for most areas this afternoon, but it may hang around across northeastern MD where low-level moisture is deepest. Highs will range from the lower to middle 60s across northeastern MD where clouds and drizzle are expected, to the upper 60s/near 70 around the Washington Metro area, to the mid and upper 70s in central Virginia as well as the valleys of the Potomac Highlands.
A northerly flow is expected to continue tonight as high pressure draws closer from the north. However, low-level moisture will likely remain trapped underneath the subsidence inversion, resulting in more low clouds for most areas. Some radiation fog is possible in the valleys of the Potomac Highlands into the central Shenandoah Valley where there will be less low clouds to start this evening. A few showers and drizzle are still possible, mainly across northeastern MD and near the Bay where low-level moisture will be deepest.
Short Term - Saturday Through Sunday Night
Upper ridging will begin to build quickly over the region early on Saturday leading to mid-level drying and subsidence. However, stubborn low clouds/stratus will more than likely persist through the day Sat with perhaps patchy light drizzle. Pleasant day on Sunday with clear skies and temperatures approaching 80.
Long Term - Monday Through Thursday
An omega block pattern across the central CONUS sets up during the long term period, with strong upper ridging expected across the entire eastern third of the CONUS. This will yield warmer temperatures and mostly sunny skies through most of the long term period. Highs each day will top out right around 80 with overnight lows in the 50s.
The trough across the central CONUS will gradually be pushing eastward throughout this period, but Thursday looks to be the earliest that we would see any precipitation. Introduced some slight chance POPs late Thursday as a result.
SCAs (Small Craft Advisories) have been extended through Sat and may need to be extended further in time through Sunday. Winds should start diminishing quickly Sunday afternoon.
Strong upper-level ridging will dominate the weather pattern through mid-week at least. Winds will remain mostly calm during this time, staying well below SCA (Small Craft Advisory) criteria.
Tides / Coastal Flooding
Water levels have begun to drop over the Chesapeake Bay and Potomac River as winds have taken on a more NNE component. For now, am keeping as advisories and warnings as is, but will revisit them before 7AM. Will probably be canceling some advisories in northern areas and downgrading St. Mary's to an advisory.
NOAA Baltimore MD/Washington DC Office: Watches - Warnings - Advisories
DC...Coastal Flood Advisory until 11pm EDT this evening for DCZ001. MD...Coastal Flood Advisory until 5pm EDT this afternoon for MDZ016. Coastal Flood Advisory from noon today to 5am EDT Saturday for MDZ017. VA...Coastal Flood Advisory until 5pm EDT this afternoon for VAZ057. WV...None.
Small Craft Advisory until 6pm EDT Saturday for ANZ530>534- 537-539>541-543.