Tidal Potomac from Key Bridge to Indian Head MD Marine Forecast
|Today...Ne Winds 5 To 10 Kt. Waves 1 Ft. Rain.|
|Tonight...Ne Winds 5 To 10 Kt. Waves 1 Ft. Rain Likely.|
|Mon...E Winds 10 To 15 Kt. Waves 1 Ft. Rain Likely.|
|Mon Night...E Winds 10 To 15 Kt. Waves 1 Ft. Rain Likely.|
|Tue...Se Winds 5 To 10 Kt. Waves 1 Ft. A Chance Of Rain.|
|Tue Night...S Winds 5 Kt. Waves Less Than 1 Ft.|
|Wed...W Winds 5 Kt. Waves Less Than 1 Ft. A Chance Of Showers In The Morning. Showers Likely.|
|Thu...E Winds Around 5 Kt. Waves 1 Ft Or Less. Showers Likely, Mainly In The Morning.|
|Area Forecast Discussion|
National Weather Service Baltimore MD/Washington DC
404am EDT Sunday September 23 2018
Synopsis: High pressure will continue to build across northern New England through Monday, then move off the coast Tuesday. The next cold front will move across the area during the middle part of the week.
Near Term - Through Tonight
Overrunning/warm advection pattern is expected to strengthen later this morning and will be aided by RRQ jet dynamics to result in a period of moderate rain today. Heaviest amts are expected across eastern WV (Grant, Mineral into Hampshire and Hardy counties). Rainfall amounts are likely to average around 0.75 inches with up to 1.5 inches possible as suggested by GEFS and EPS members. Given that the rain is expected to be stratiform in nature and fall in a 12-hr period, most places should be able to handle this amount of rain, so no flooding issues are anticipated.
Rain should become much lighter late tonight as upper forcing weakens and shortwave ridge builds in.
Short Term - Monday Through Tuesday Night
Another round of light to moderate rain appears likely late Mon into Tuesday morning as h85 warm front lifts through the area aided by shortwave energy and h25 jet dynamics. Rain should taper off Tuesday afternoon, but with low clouds remaining.
Long Term - Wednesday Through Saturday
The upper levels during the second half of next week and into the weekend will be undergoing a change from a pattern featuring large scale ridging off the southeastern US coastline and large scale troughing over the upper midwest to a pattern that is much more zonal in nature.
A low pressure system will be intensifying and moving northeastward through the Great Lakes on Wednesday, placing the region in southwesterly flow out ahead of an approaching cold front. The cold front will make its way eastward during the day, likely crossing into the area during the afternoon and evening hours. Thus, there will be increased chances of showers/thunderstorms, especially Wednesday afternoon and evening. Temperatures should be above normal with morning lows in the 60s to near 70F and highs in the 80s.
The frontal boundary will likely stall or wash out near the region Wednesday night through Thursday night, although there is uncertainty with how far south/east the front can progress. With a possible frontal boundary nearby, good jet dynamics aloft, southwest flow in the mid/upper levels, and northeasterly surface flow induced by a strong high pressure over SE Canada, will favor model solutions depicting rain chances continuing on Thursday/Thursday night. Temperatures should cool behind the boundary to near normals, although will be dependent on evolution of clouds/rain.
As the pattern continues to transition, another system will pass near or north of the region on Friday, allowing high pressure to build into the area over the weekend. Will keep lingering shower chances (although lower) on Friday, with drying shown by Saturday. Highs in the 70s, lows in the 50s to near 60F.
Will likely be issuing Small Craft Advisory for the lower bay and lower Potomac, winds then expected to strengthen later today and remain gusty through at least Monday as pressure gradient tightens.
Potential exists for Small Craft Advisory conditions to develop by Wednesday afternoon ahead of an approaching cold front. Chances for showers/thunderstorms will be increasing as well. Sub-Small Craft Advisory conditions likely Thursday as a front stalls near or south of the waters
NOAA Baltimore MD/Washington DC Office: Watches - Warnings - Advisories
DC...None. MD...None. VA...None. WV...None.
Small Craft Advisory from 8am this morning to 6pm EDT Monday for ANZ532>534-537-541>543