textproduct: Wakefield

WHAT HAS CHANGED

The late week system has trended much more progressive/faster and weaker with lower chances for any accumulating wintry precipitation.

KEY MESSAGES

1) Dry with seasonable/slightly above average temperatures through midweek.

2) Low pressure develops along a cold front Wed night, and passes by N of the area Thursday, bringing a chance for rain, potentially ending as a brief period of snow early Thursday.

3) Mainly dry with cold/below normal temperatures Friday into early next week, with a low end chance for precipitation Sunday.

DISCUSSION

KEY MESSAGE 1...

Strong sfc high pressure (~1030mb) is centered along the western Gulf coast region this aftn, ridging ENE into the local area w/ a weak trough aloft bringing a fast moving westerly flow in the upper levels. Sunny with seasonable temperatures this aftn (readings from the mid 40s to around 50F). RH Values have dropped to less than 30% in many areas and blended guidance continues to do terrible so have lowered dew pts significantly through Tuesday. High pressure stays situated S of the region through Wednesday, as low pressure moves across the northern Great Lakes, pushing into the St Lawrence Valley by Wed AM. Seasonable and cool tonight with lows in the mid 20s to lower 30s, followed by SW winds in the low levels become a bit stronger on Tue, pushing highs well into the 50s for most under a mainly sunny sky (near 60F in the SE). Clouds increase Tue night/Wed, but most areas stay dry Wed, along with mild temperatures.

KEY MESSAGE 2... Models have continued the more progressive/drier trend that began with last night's 00Z runs for the system late this week. The consensus now focuses the highest PoPs late Wed night/Thursday morning, with a dry slot arriving rather quickly from the SW thereafter. The faster arrival of colder air does allow for a changeover to snow early Thursday morning over at least the NW portions of the FA, though it is increasingly looking as if the colder air will be chasing the departing moisture given that the developing upper low is now forecast to be over the Great Lakes and into the St Lawrence Valley (about 200 miles N of what the consensus was yesterday at this time). With the primary shortwave tracking more N of the region., expect rapid drying through the column and a minimal precip chance after 12Z except perhaps over the NE zones. Will maintain low PoPs for now for continuity, but would not be surprised to see these chances drop off completely w/ later forecasts. Have confined any SN accumulation to the far N. Otherwise it will be rather cold and breezy Thursday (highs struggling to get out of the 30s N and in the 40s S) w/ diminishing clouds. Cold w/ lows in the teens and 20s Thu night- probably not quite cold enough for Cold Weather Advisories but close.

KEY MESSAGE 3... The extended period will primarily feature below normal temperatures with mainly dry conditions as an upper level ridge persists across the west coast of North America, keeping an upper level trough in place from central Canada into the SE CONUS. At this point, the best chance for any precipitation looks to be on Sunday, though PoPs remain low at only 15-30% as the overall pattern appears too progressive to tap into any southern stream moisture.

AVIATION /06Z TUESDAY THROUGH SATURDAY/

As of 1145 PM EST Monday...

VFR conditions currently across area terminals will prevail through the 06Z/13 TAF period. Light W-SW winds average 5-7 kt overnight under a mainly clear sky. Expect SW winds to increase a bit on Tuesday late morning, gusting to 15-20 kt by afternoon.

Outlook: Dry/VFR conditions are expected across the mid-Atlantic through midweek. Increasing low-level wind shear is expected ahead of an approaching cold front late Tuesday evening into Wed morning. The front will cross the region Wed evening, with some light rain possible behind the front late Wed night into Thursday morning. A brief period of sub-VFR conditions will be possible early Thu morning, as a secondary front crosses the region, ushering in a much colder airmass for the late week period.

MARINE

As of 330 PM EST Monday...

- Sub-SCA conditions prevail through Tuesday evening with SW winds as high pressure to the southwest influences the area.

- A brief period of SCA conditions likely Tuesday night into Wednesday morning with increased SW winds and seas.

- A series of cold fronts will cross the region late this week with strong SCA conditions possible Thursday into Friday.

The latest surface analysis shows a strong ~1034 mb high pressure centered over the southeast CONUS, influencing the local waters and allowing for sub-SCA conditions across all waters currently. SW winds 10-15 kt and seas of 1-3 ft (waves ~1 ft) were observed at the time of writing. Tonight into Tuesday, the high will weaken some and translate offshore from a strong low pressure system moves over the Great Lakes. Winds and seas will remain below SCA thresholds, around 10-15 kt and 1-3 ft, through the day Tuesday.

Then, with the approaching low pressure system and decreased high pressure, a strong LLJ around 40-50 kt will increase the winds and seas Tuesday night into Wednesday morning. Confidence has increased in SCA conditions with SW winds increasing to 15-20 kt with gusts to 25 kt in the Ches. Bay and coastal waters north of Cape Charles. The southern coastal waters will likely see lower wind speeds at 10-15 kt. Local wind probs show 70-90% probs of sustained 18 kt gusts in the middle bay, with 40-50% probs in the lower bay and mouth of the bay. In the northern coastal waters, probs have increased to 50-80% probs of 25 kt gusts. Additionally, seas and waves will increase to 3-5 ft north of Cape Charles (2-3 ft south) and 2-4 ft in the Ches. Bay (highest waves in the middle bay). After collaboration with neighboring offices, have held off on issuing SCA at this time, but will likely need issuing in the next package if trends remain.

Then on Wednesday, a dry cold front will gradually cross the local area by Thursday morning, with a stronger secondary front moving through the area during the day Thursday. SW winds on Wednesday will to be NW behind the fronts, increasing during the day Thursday to likely SCA conditions. The surge of strong CAA may be slightly lagged, impacting the area Thursday night, which would allow winds to increase again. Local wind probs have decreased slightly for gale forced gusts Thursday night, now at 30-50% for the coastal waters. Will continue to monitor the trends with future forecasts. Another series of cold fronts may impact the local waters this weekend.

AKQ WATCHES/WARNINGS/ADVISORIES

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