textproduct: Wakefield

WHAT HAS CHANGED

Probabilities for light snow, sleet, and/or freezing rain continue to decrease for the early week system. Temperatures from mid week into next weekend continue to trend slightly warmer.

KEY MESSAGES

1) Light snow, sleet, and/or freezing rain Monday afternoon into early Tuesday morning is possible, but probabilities for any accumulation continue to remain low.

2) A significant warming trend is expected by the middle of the week into next weekend.

DISCUSSION

As of 330 PM EST Sunday...

KEY MESSAGE 1...Light snow, sleet, and/or freezing rain Monday afternoon into Tuesday morning is possible, but probabilities for any accumulation continue to remain low.

A backdoor cold front is pushing S along the coast this afternoon. As is common with these fronts, they make more progress along the coast during the day and stall inland until after peak heating. Therefore, temperatures vary widely from the lower 40s along the MD coast, to the upper 40s/lower 50s across the remainder of the Eastern Shore and coastal SE VA/NE NC, to the 60s to lower 70s well inland. The backdoor front will push through the entire area tonight as 1040mb high pressure builds across New England. Forecast lows range from the upper 20s/around 30F N to the upper 30s S.

High pressure remains anchored over New England Monday maintaining onshore NE flow across the region. Temperatures will struggle to rise and have continued the trend of going below NBM temperatures and closer to MOS numbers given onshore flow and increasing clouds. An initial impulse arrives from the W by Monday afternoon. Light precipitation is expected to develop, and the depth of the cold air should be sufficient to produce light snow across central VA provided 2m temperatures are cold enough later Monday afternoon. Some locations could begin as light rain and then change to snow as the temperature trends toward the wet-bulb. Farther S/SE mainly rain is expected. A series of weak disturbances will lift across the region Monday night into Tuesday morning. The potential for light snow will shift NE Monday evening, with the depth of the cold air shallowing with time from SW-NE Monday night into Tuesday morning as the high to the NE is progressive. Light snow, sleet, and potentially some light freezing rain are possible over portions of the area late Monday into early Tuesday. Most model guidance supports very little snow accumulation/ice accretion and the GFS/GEFS remain the most robust for accumulation and are generally considered outliers. Any accumulation will likely be limited to tree tops/elevated surface and should limited to low impacts.

KEY MESSAGE 2...A significant warming trend is expected by the middle of the week into next weekend.

A rapid change to warmer temperatures is expected by the middle of the week after the cool start to the week. Ensemble guidance is depicting a large upper ridge over the eastern U.S, with 850 mb temperature anomalies well above average. If this set-up comes to fruition (in which confidence is increasing), temperatures will rise to well above normal, with highs potentially reaching the lower to mid 70s by late next week and lows only dropping into the upper 40s to near 50F. By the weekend, some guidance is edging very close to and above the 80F mark for inland areas. This week will be there first time that Richmond will have seen highs >=70F since right before Thanksgiving. The last time that 70F was not reached during meteorological winter was during the 2009-2010 winter. While there is good agreement on the overall synoptic pattern, there is always a chance that the colder airmass associated with the backdoor cold front is a little slower to leave. However, with the strength of the ridge and the continued very good ensemble consensus, this scenario is looking more and more unlikely, so have continued to maintain well above normal temperatures late week and into the weekend. A series of weak fronts bring minimal chances for showers (mainly N) toward the end of next week, but widespread rainfall is not expected.

AVIATION /06Z MONDAY THROUGH FRIDAY/

As of 1250 AM EST Monday...

VFR conditions will prevail at all terminals through around midday before a system starts to bring in a mix of precipitation types to the area. RIC and SBY will likely see -SN and/or -RASN to start the event tomorrow afternoon. PHF and ORF may see a brief period of light RASN, but confidence was too low to include for now so have just kept -RA for both terminals (as well as ECG). Once the precip arrives at each respective terminals, VIS and CIGs will drop down into MVFR and at least CIGs will approach IFR by late tomorrow evening. The wind is expected to be NE 8-12kt inland, and 10-15kt with gusts to 20-25kt toward and along the coast. Winds will start to decrease overnight.

IFR to LIFR cigs are possible through Tuesday morning. VFR and mainly dry conditions are expected to prevail Wednesday through Friday, though a few widely scattered showers will be possible Thu/Fri.

MARINE

As of 330 PM EST Sunday...

Key Messages:

- SCAs are in effect this afternoon into Monday for all zones except for the upper rivers as a backdoor cold front drops south through the area.

- SCAs for the southern coastal waters have been extended in time, now through Tuesday afternoon as elevated wave heights persist.

Latest analysis shows the backdoor cold front has crossed most of the local waters, with the exception of the NC waters. Strong high pressure over the Great Lakes has pushed this front across the area. Winds are currently NE around 15-20 kt with gusts to 25 kt. Waves and seas are around 1 ft and 2-3 ft, respectively. A moderately tight pressure gradient and height increases will allow winds to remain elevated through Monday afternoon. A brief period of gusts to 30 kt is possible this afternoon/evening. Latest CAMs have gusts remaining elevated in the southern waters and lower Ches. Bay a bit longer than previous runs on Monday afternoon. With this, have extended the SCA for the lower Ches. Bay zone through Monday evening. It may be a bit marginal for the mid/upper Bay and the coastal waters N of Cape Charles outside of this initial push in the aftn, but still close enough to not change the headlines. NE winds around 15-20 kt with gusts to 25 kt will prevail into Monday.

Seas will increase to 3-5 ft N and 5-6 ft S, and waves to 3-4 ft, peaking early Monday morning. Expect 5 ft seas to linger into Monday night in the southern waters. Seas may stay a bit elevated Tue-Wed, and have extended SCA for the southern coastal waters now through Tuesday afternoon. Winds become SSW late Tuesday and should remain southerly through late week, with benign marine conditions.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 10 AM EST this morning for ANZ630- 631. Small Craft Advisory until 7 PM EST this evening for ANZ632- 634. Small Craft Advisory until 1 PM EST this afternoon for ANZ633- 638-650-652-654. Small Craft Advisory until 1 PM EST Tuesday for ANZ656-658.