Marine Weather and Tide Forecast for Upper Marlboro, MD

KEY MESSAGES
- 1) Low pressure, moving across southern Great Lakes into southeastern Canada Thursday, will drag a strong front through the region late week. Showers will be followed by wind and cold.

- 2) Relatively dry & very warm conditions to begin the work week before chances for showers and a thunderstorms return by Wednesday evening.

DISCUSSION
KEY MESSAGE 1...Low pressure, moving across southern Great Lakes into southeastern Canada Thursday, will drag a strong front through the region late week. Showers will be followed by wind and cold.

Low pressure will move from the central Plains into the southern Great Lakes Thursday, then into southeastern Canada Thursday night, before pushing into southeastern Canada Friday. A midweek cold front that could bring a few showers or a rumble of thunder to parts of the region will stall before pushing northward as a warm front and connect to the aforementioned low pressure system that will move into southeast Canada. As both the warm front and low pressure push north and northeastward mid- late week, a strong cold front extending from the low will push rapidly through the region. Noticeably colder air will push in behind the cold front and spread throughout the region Friday night into Saturday. Increased chances of precipitation will accompany this complex system. The warm front may bring higher rain chances along the Mason-Dixon and northern areas. The low will stay to our north; however, the strong cold front will bring another round of showers and perhaps some thunder to any parts of our region late in the week. There may be enough cold air and moisture with cold frontal passage that rain showers may mix with snow showers at the highest elevations of western Maryland and northeastern West Virginia Friday night into early Saturday. Little to no snow accumulations expected at this time.
High pressure will bring dry and cool conditions the remainder of the day Saturday and through Sunday. Northwest winds could gust 20 to 30 mph with as much as 40 mph in higher elevations behind the strong cold front. Wind headlines may be needed late week into the early half of the weekend.

In terms of temperatures, most areas from the Mason-Dixon and south to just north of US 33 could feel the affects of the midweek cold front and have temperatures near average on Thursday. Areas into the Virginia Piedmont and central Shenandoah Valley could have above average temperatures as they will be south of the front. Temperatures will be primarily in the middle to upper 60s. All areas should feel the affect of a surging warm front where temperatures warm up into middle to upper 70s on Friday. This, of course, will be right before the strong cold front plunges southward and drops our temperatures from the middle 70s to the middle 40s over a 12 hour period into early Saturday morning. Highs on Saturday could struggle to reach 60 degrees anywhere. As a matter of fact, highs in the mountains could only reach the upper 30s to middle 40s. Sunday may only be a few degrees milder with highs reaching the upper 50s in the west and north and near 60 elsewhere.

KEY MESSAGE 2...Relatively dry & very warm conditions to begin the work week before chances for showers and a thunderstorms return by Wednesday evening.

As remnants from Isaias fully clear out of our region today, mid- level ridging builds over the region through the middle of the week.
High pressure and southwesterly surface winds lead to mostly dry and sunny conditions Tuesday and Wednesday morning. Daytime temperatures raise into the low to mid 80s both days, well above average for mid- October.

Wednesday afternoon, a surface high over the Dakotas slides westward over the Great Lakes, nudging a low pressure system over the Ohio River Valley south into Kentucky and West Virginia. Northwesterly winds off of this high slowly advances a cold front southwards before stalling out in Virginia. A few showers and thunderstorms could form Wednesday afternoon as the warm front associated with the low over the Tennessee Valley slides northward into our area. With this stalled front lingering in the area, showers and thunderstorms remain possible across our forecast area through Thursday evening.
The best chances for showers and thunderstorms lies west of the Blue Ridge.

AVIATION /18Z MONDAY THROUGH SATURDAY/
VFR conditions are forecast to return. Northwest winds will diminish this evening. As ceilings continue to lift and cloud cover wanes, all terminals are expected to reach VFR conditions by this evening. With high pressure building, VFR conditions are expected to last through Wednesday morning. Northwesterly winds turn southerly tomorrow with gusts ranging around 10-15kts tomorrow afternoon. Winds slightly weaken Wednesday turning east to southeasterly Wednesday morning.

Primarily VFR conditions expected Thursday. A nearby front brings a slight chance of precipitation to MRB and CHO where restrictions are possible. On Friday, sub- VFR conditions are possible across all terminals as a cold front moves across the forecast area, bringing precipitation. Additionally, south winds in the morning shift to northwesterly by the evening gusting 20 to 30 knots.

MARINE
As winds continue to quickly weaken, Small Craft Advisories will conclude this afternoon. Northwesterly winds today turn southerly tomorrow with gusts approaching SCA criteria over the Chesapeake Bay in the afternoon hours. This southerly channeling effects subside Wednesday as gusts will remain below 15kts and shift out of the southeast.

North/northeast winds on Thursday shift to southerly on Friday morning before shifting to northwest Friday afternoon. Winds near SCA criteria on Thursday with advisories possible across the open waters. A strong pressure gradient between high pressure to the west and low pressure in the NE will bring gusty winds on Friday. SCA conditions are expected with near gale force winds possible Friday night.

LWX WATCHES/WARNINGS/ADVISORIES
DC...None.
MD...Small Craft Advisory until 3 PM EDT this afternoon for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 3 PM EDT this afternoon for ANZ530>532-535-536-538>542.
Small Craft Advisory until 6 PM EDT this evening for ANZ533- 534-537-543.