textproduct: Wakefield

SYNOPSIS

A series of clipper systems late this week and again at the end of the weekend will bring some additional light wintry precipitation to the region, with some accumulating snow possible Sunday. Behind the late weekend system, Arctic air moves in Sunday night, and provides a cold start to next week. The very cold temperatures do quickly give way to relatively milder temperatures for the middle to end of next week.

NEAR TERM /UNTIL 6 AM FRIDAY MORNING/

As of 640 PM EST Thursday...

Key Message:

- Dry and cool tonight with increasing high clouds.

GOES water vapor channels depict an upper trough over the East Coast this evening. At the surface, strong low pressure was centered over the Gulf of Saint Lawrence, with a trailing cold front well offshore of the Mid-Atlantic coast. Meanwhile, high pressure was centered over the Deep South. Mostly clear and cool this evening with temperatures ranging from the low-mid 30s across the area. Continued breezy over the Eastern Shore where a NW wind is gusting up to 25-30 mph across mainly Dorchester County. Surface high pressure slides across the Southeast tonight. Mostly clear this evening, with clouds increasing from W-E overnight. Forecast lows range from the mid 20s to lower 30s.

SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/

As of 305 PM EST Thursday...

Key Messages: - A weak clipper system swings across the region Friday, bringing some light snow to the Piedmont and I-95 corridor.

- An Arctic cold front crosses into the region Sunday, ushering in a much colder airmass Sunday night and Monday. Some snow is possible with the Arctic frontal passage, especially from the Neck to the Eastern Shore.

A clipper system is dropping SE out of the northern/central Plains this afternoon, and is expected to drop through Friday. Deterministic models and CAMs have come into general agreement with the track of this system, but continue to show minimal impacts with this weakening system due to light QPF and marginal surface temperatures. Both EPS/GEFS ensemble probs are in the 20-40% range for probabilities for at least 1" of snow, with a slight placement differences (the GEFS is slightly N of the EPS). Bufkit soundings from the 11/12z NAM/GFS depict that snow will be falling for a few hours Friday morning into early aftn for the Piedmont and I-95 corridor, before drier air limits precip to the N and NE. Forecast snowfall amounts range from 0.5-1" over the Piedmont (highest , to a few tenths across the I-95 corridor. Most snow accumulation will primarily be on the grass and elevated surfaces. Highest along the US 460/US 360/US 60 corridors in the Piedmont. High temperatures range from the mid 30s over the Piedmont, to the lower 40s across far SE VA/NE NC.

Dry weather conditions will return Friday night into Saturday, with slightly warmer temperatures. Lows Friday night in the 20s to low 30s. Highs Saturday will be in the mid 40s across the N and low 50s across the S.

Main weather item of note remains the strong Arctic cold front that will drop across the area Sunday into Sunday evening. Snow potentially develops across the northern tier of the area late Saturday night and continues through midday Sunday. Farther SE, as of now, looks to be more of a situation where cold air is chasing moisture, which points toward a situation of rain ending as a brief period of snow for Hampton Roads and NE NC. EPS/GEFS probs for >= 1" of snow are 50-80% for the MD Eastern Shore, and generally 30-50% from the Northern Neck through the VA Eastern Shore, with the GEFS displaced more to the S. 3" probs are negligible this model cycle. Forecast snow amounts this cycle are 1-2" across the northern tier of the area (LKU-XSA- SBY), 0.5-1.0" from FVX-RIC-WAL, and less than 0.5" farther S. Lows Saturday night range from the upper 20s/lower 30s N to the mid/upper 30s S. Temperatures Sunday may rise a few degrees Sunday morning, then become steady, before falling by late afternoon as drier/colder air arrives from the NW.

LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/

As of 305 PM EST Thursday...

- Cold early next week with moderating temperatures through the middle of next week.

Strong high pressure builds in from the NW Sunday night into Monday, ushering in much colder temperatures. Lows Monday AM are expected to plummet into middle to upper teens and low 20s along the coast, with chilly highs Monday in the 30s. Breezy conditions early Monday will result in wind chills dropping into the single digits.

There is broad and improving consensus that cold high pressure quickly slides offshore Tuesday through midweek. Cold Monday night into Tuesday morning with lows in the lower to mid 20s, followed by highs in the 40s Tuesday. A noticeable warm-up is then expected by Wednesday/Thursday. Dry through Wednesday, with low rain chances returning Thursday.

AVIATION /00Z FRIDAY THROUGH TUESDAY/

As of 635 PM EST Thursday...

High pressure continues to build into the area this evening. VFR conditions continue through tonight with increasing clouds and calm to light and variable winds. A weak low pressure tracks across the region Friday. This will result in increased cloud cover and the chance for a period of light snow across inland portions of the area from Fri morning into early Fri afternoon. MVFR to IFR CIGs (as well VIS due to snow showers) are possible across the Piedmont to RIC from late Fri morning into at least early Fri evening. However, the latest model guidance keeps IFR CIGs west of RIC. For the remainder of the terminals, primarily VFR conditions continue, however, cannot rule out a period of MVFR CIGs at PHF early Fri afternoon. Given the low confidence in heavier snowfall rates (and accumulating snow) at RIC, have kept a PROB30 for IFR VIS for now in the taf.

Clouds linger through Fri night. However, CIGs are expected to improve to VFR across all terminals. Another (stronger) cold front crosses the region late Sat night into early Sun. This could bring a period of a rain/snow mix followed by all snow late Sat night through midday Sun. Turning much colder with gusty NNW winds Sun afternoon. VFR conditions return Sun night through Tue.

MARINE

As of 305 PM EST Thursday...

Key Messages:

- Marine conditions continue to improve this afternoon and and into tonight.

- Benign marine conditions are expected both Friday and Saturday with high pressure in control.

- Confidence increases for Gale force winds as a strong cold front moves across the local waters Sunday into Monday.

Afternoon weather analysis shows a sub 980 low across northeastern Canada and a 1020mb high pressure over the Gulf coast. The pressure gradient from these two systems have slacked across the southern half of the area allowing winds to lower to 10 to 15 kt. Therefore, the SCA have been able to expire across the southern and mouth of the bay and the two southern ocean zones. While across the the middle and upper bay and the additional ocean zones remain in a SCA due to the pressure gradient remaining slightly stronger allowing winds to remain between 15 to 20 kt with gusts upwards of 25 kt. These SCA are expected to be dropped at 4pm as the pressure gradient weakens and winds lower. In addition, the seas have lowered and are between 3 to 4ft across the ocean and 1 to 2ft across the bay. Through tonight and into early Sunday high pressure is expected to move into place bringing benign marine conditions. Winds are expected to remain light with sustained winds between 5 to 10 kt. Seas are will be between 2 to 3 ft across the ocean and around 1 ft across the bay.

By early Sunday a strong cold front is expected to move over the waters. Recent model guidance continues to show a very cold airmass moving into place. This airmass will cause strong mixing to occur over the waters and will bring Gale conditions. Local wind probs continue to show 90%+ of wind gusts >= 34kt gusts. With great model agreement and high wind probs there is high confidence in Gale force winds. As of this forecast update winds are expected to be out of the NW between 25 to 30 kt with some locally higher sustained winds and gusts upwards of 35 to 40 kt. At this time, no watches have been issued due to how far out the event is. However, confidence is high in Gale conditions. Seas will also increase with these winds and will be between 4 to 5 ft across the bay and 6 to 8 ft across the ocean.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...None.