Marine Weather and Tide Forecast for Port Royal, VA

KEY MESSAGES
- 1) Well above normal temperatures for first half of week.

- 2) A strong cold front brings gusty winds, colder temperatures, and widespread shower/thunderstorm chances starting Wednesday.

DISCUSSION
KEY MESSAGE 1..Well above normal temperatures for first half of week.

The cold front finally drags through the area this afternoon, scouring out the lingering clouds and light rain. Dry and cooler air tonight drops lows to the 40s across the area. Sunny conditions with well above normal temperatures expected Monday and Tuesday, with near record warmth lingering through mid week. Highs reach the 70s to low 80s, which is about 15-25 degrees above normal for mid-March.

KEY MESSAGE 2.. A strong cold front brings gusty winds, colder temperatures, and widespread shower/thunderstorm chances starting Wednesday.

Not too much change in regards to timing or hazards for the midweek period. Still monitoring the deep digging upper level trough dropping down out the Great Lakes region as well as a piece of southern stream energy ejecting out of the southern Plains region.
At the surface, will lay a strong cold frontal boundary which will flip the script when it comes to late Winter and early Spring. 6/12z guidance still has this front progged to move through the area some time late Wednesday into Thursday. As for severe weather, it will be highly dependent on timing with a focus remaining west of the Blue Ridge. This is the area where better instability and shear may be maximized given a lead shortwave that should touch off some convection over the mountains Wednesday afternoon as the northern stream trough tries to take a negative tilt. CSU learning machine probabilities remain around 15 to 30 percent for all severe hazards for the entirety of the area Wednesday afternoon into Thursday. NSSL probabilities are quite similar with a focus more on areas west of US-15 and out across the Allegheny Mountains.

Meanwhile, SPC continues to highlight a 15 percent probability zone for portions of Garrett Co. MD during the Day 4 (Wednesday into Thursday). Storms will have plenty of fuel to work with as temperatures surge into the 70s and low 80s with dewpoint factors getting into the upper 50s and low 60s. Shear is a bit more uncertain with strong southwesterly flow at the surface ahead of the front and gusty northwesterly flow likely behind the front heading into the Thursday timeframe. Also, any early convection over the mountains combined with a later timing of the front (i.e Wednesday night into Thursday) could hamper convective output. Wind and heavy rainfall would be the primary threats for storms if they can develop Wednesday afternoon into Wednesday night.

The bigger story with the front will be the notable drop in temperatures heading into late week. Temperatures will take a 15 to 25 degree dive Thursday with highs ranging from the 30s over the mountains to low 60s east of I-95 and across southern MD/central VA Piedmont. Some anafrontal snow is even possible in the Alleghenies as the front departs Thursday afternoon into Thursday evening.
Temperatures do level out Friday with highs in the upper 40s over northeast MD/the Alleghenies and mid to upper 50s elsewhere across the region. Similar values are expected this weekend despite another front passing through the region.

Winds will gusts 20 to 30 kts (25 to 35 mph) in southwesterly flow Wednesday boosting the temps well into the 70s before switching to the northwest Thursday with gusts 25 to 35 kts (30-40 mph; locally higher mtns). Rainfall amounts remain a bit uncertainty with most locations picking up a quarter to a half an inch. Higher amounts can be found across the Alleghenies and in areas that see convection.
Any rain will be beneficial given the recent drought concerns.

AVIATION /18Z SUNDAY THROUGH FRIDAY/
A cold front pushes through the area this afternoon. VFR conditions are expected to prevail through Tuesday as sunnier skies return.

A strong cold front will bring the return of sub-VFR conditions as late Wednesday into Thursday. Showers and even a few thunderstorms look to impact the terminals during this time. Outside of the shower and thunderstorm threat will be the wind. Expect gusty south to southwesterly winds up to 25 kts Wednesday switching to the northwest with gusts 25 to 35 kts Thursday afternoon. Winds will gradually decrease late Friday with high pressure nearby. Additional wind is expected this weekend as another front passes through the region.

MARINE
A cold front moving through the area this afternoon could produce occasional gusts to around 20 knots. This threat will be handled with Marine Weather Statements as the duration is short, gusts intermittent, and also it will be difficult for gusts to mix down given the cold waters. After that, sub-SCA winds prevail through Tuesday in a light southerly wind.

SCA conditions are possible in southerly channeling Wednesday into Wednesday night. Gusts of 20 to 25 kts are possible, especially over the open and middle waters of the bay/tidal Potomac. A strong cold front will cross the waters late Wednesday night into Thursday. This will lead to gusty post frontal north to northwest flow. Gusts of 25 to 35 kts can be expected with even some northerly channeling over the northern bay. Winds will gradually decrease Friday into Saturday while remaining at SCA levels as another front pushes through.

CLIMATE
Daily high records could be tied or set Monday through Wednesday.

Wednesday is the most likely day for warm low records to be tied/set due to cooler air arriving after midnight Wednesday night.

Washington DC (DCA)
Date March 9 March 10 March 11 Record High 80F/1964 79F/2016 79F/2021 Record Warm Low 52F/2000 57F/2016 57F/2016

Washington-Dulles (IAD)
Date March 9 March 10 March 11 Record High 82F/2016 80F/2016 79F/2021 Record Warm Low 46F/1964 59F/2016 49F/1967

Baltimore (BWI)
Date March 9 March 10 March 11 Record High 82F/2016 80F/2016 79F/2021 Record Warm Low 56F/1921 57F/2016 53F/1955

Annapolis (NAK)
Date March 9 March 10 March 11 Record High 78F/2000 78F/2016 74F/1967 78F/1964 Record Warm Low 58F/1921 56F/2020 52F/1986

Charlottesville (CHO)
Date March 9 March 10 March 11 Record High 81F/2016 80F/2016 83F/1925 Record Warm Low 59F/1921 58F/2020 53F/2016

Martinsburg (MRB)
Date March 9 March 10 March 11 Record High 81F/2016 80F/2016 78F/2021 81F/2020 Record Warm Low 49F/2000 53F/2016 49F/1955

Hagerstown (HGR)
Date March 9 March 10 March 11 Record High 80F/2016 80F/2016 79F/2021 Record Warm Low 49F/2002 57F/2016 53F/2016 49F/1992

LWX WATCHES/WARNINGS/ADVISORIES
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.