Marine Weather and Tide Forecast for Deale, MD

KEY MESSAGES
- 1) A strong cold front pushes across the forecast area Monday, bringing gusty winds and potential for severe thunderstorms capable of producing significant damaging winds and tornadoes.

- 2) Unseasonably Cold Conditions Tuesday and Wednesday.

DISCUSSION
KEY MESSAGE 1...A strong cold front pushes across the forecast area Monday, bringing gusty winds and potential for severe thunderstorms capable of producing significant damaging winds and tornadoes.

Precipitation chances begin increasing Sunday as a potent low pressure system traverses across the Great Lakes into Canada, pushing the associated fronts across the Mid-Atlantic. The associated warm front lifts through the area Sunday night with the cold front tracking across the region during the day Monday. Aloft, a robust trough digs across the central CONUS, becoming slightly negatively tilted as it approaches and pivots across the east coast Monday. This will push the aforementioned cold front across the forecast area, bringing impactful weather throughout the day.

In the wake of the warm front lifting through Sunday night, high temperatures on Monday will be in the mid 60s to mid 70s.
Additionally, with southerly flow, dewpoints rise into the upper 50s to low 60s across much of the forecast area ahead of the cold front. Storms may initiate Monday morning with any shower/storm capable of producing gusty winds due to a strong wind field aloft. Later Monday morning and into the afternoon, storms develop along the cold front as it moves through from west to east. Damaging winds are likely with severe storms capable of producing significant damaging wind and tornadoes.
With such a strong wind field aloft, there is the potential for wind gusts of 70 to 80 mph within severe storms.

Current model guidance shows 300-400 m2/s2 SRH and up to 1400 J/kg SBCAPE which is compatible with a tornado risk across the area. SPC has the forecast area along and east of the I-81 corridor in an enhanced risk for severe weather with the rest of the forecast area in a slight risk. PWATS will be seasonably high, although a fast storm motion limits the flooding risk.

Outside of convective wind gusts, a tight pressure gradient will lead to gusty winds ahead of and behind the front. Cold air will be rushing in immediately following the frontal passage. At a minimum, the Allegheny Mountains will change to snow for a time in upslope conditions. It remains uncertain if any post-frontal precipitation lingers to the east long enough to change over.
For now, have a trace across the forecast area as temperatures plummet with lingering precipitation.

Cold and windy conditions linger into Tuesday with the upper trough overhead. Tuesday night will likely be the coldest night of the stretch with widespread temperatures in the teens and 20s. A warming trend will then take place the remainder of the week as surface high pressure slides off the coast.

KEY MESSAGE 2...Unseasonably Cold Conditions Tuesday and Wednesday.

Below normal temperatures are likely to overspread the region Tuesday into Wednesday behind a powerful FROPA early in the week.
Highs in the 30s to low 40s Tuesday (with below freezing temps in the mountains) moderate some to the 30s to 40s on Tuesday. The coldest night of the week is likely to be Tuesday night when lows drop to the teens to low 20s.

Tuesday is likely to be blustery as northwest winds gust around 25- 35 mph during the afternoon. Reasonable higher gusts around 40-50 mph are possible if deeper mixing occurs by help of the departing upper trough and downsloping off the higher terrain. This keeps wind chills in the 20s for much of the day Tuesday.

Temperatures moderate through the end of next week with mostly dry conditions.

AVIATION /00Z SUNDAY THROUGH THURSDAY/
VFR conditions continue through the day tomorrow as surface high pressure remains overhead. Winds diminish this evening and then gradually shift from the north to east overnight, and then southeast Sunday morning as surface high pressure shifts offshore. Precipitation chances increase as a warm front lifts through the terminals Sunday night. Sub-VFR conditions are possible beginning Sunday night during precipitation and low ceilings. Low-level wind shear will also be possible at times Sunday night into Monday. Winds shift to southerly in the wake of the warm front Monday before turning northwesterly in the wake of the cold front Monday night.

Sub-VFR conditions are likely during strong thunderstorms late Monday morning and through the afternoon. Storms will be capable of producing significant damaging wind gusts between 70 and 80 mph and tornadoes.

VFR conditions likely Tuesday into Wednesday. Northwest winds gust around 25-30 knots for much of Tuesday morning to afternoon, then winds diminish Tuesday night.

MARINE
Winds remain below SCA criteria overnight before increasing Sunday morning. SCAs have been issued for all waters during the day Sunday, with winds expected to gust to around 25 knots in southeasterly flow. South winds Sunday shift to northwest in the wake of a cold front Monday. As the cold front pushes across the waters Monday afternoon and into the evening, strong to severe thunderstorms are likely with damaging wind gusts and a few tornadoes possible. SMWs may be needed as the front crosses the waters. In the wake of the cold front, gusty northwest winds will lead to additional Small Craft Advisories Monday night.

Hazardous marine conditions are likely to continue into Tuesday afternoon behind a strong cold front. Northwest winds gust 25-30 knots across the waters, then decrease steadily Tuesday evening into Tuesday night. Sub-SCA conditions likely for Wednesday.

FIRE WEATHER
Gusty winds but increasing RHs are forecast Sunday ahead of another front, which looks to bring wetting rains Sunday evening/night. There is less of a threat Sunday, but any ongoing fires could feel the impacts of some gusty southeasterly flow (20-30 mph gusts). Showers and thunderstorms look likely on Monday before strong west- northwesterly winds overspread the area Monday evening into Tuesday. High pressure returns by the middle of next week.

TIDES/COASTAL FLOODING
Increasing southerly winds ahead of a powerful cold front will cause a quick rise in tide levels across the Chesapeake Bay and tidal Potomac River. Sensitive locations are likely to reach or be close to minor flood during the Monday afternoon/evening high tide.
Annapolis is forecast to be well within minor flood stage, and could reach moderate flooding if southerly flow is stronger as some of the model guidance suggests. If confidence increases, a Coastal Flood Watch may need to be issued tonight or tomorrow. Water levels quickly drop Monday night as offshore winds take hold behind the front.

LWX WATCHES/WARNINGS/ADVISORIES
DC...None.
MD...Small Craft Advisory from 9 AM to 6 PM EDT Sunday for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory from 9 AM to 6 PM EDT Sunday for ANZ530>543.