textproduct: Wakefield

SYNOPSIS

A strong cold front crosses the the Mid Atlantic late tonight night into Sunday, with accumulating snow possible Sunday, especially on the Eastern Shore. Arctic air moves in behind the cold front Sunday evening into 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 /THROUGH SUNDAY/

As of 230 PM EST Saturday...

- A strong cold front brings low-end snow potential and blustery conditions on Sunday. Winter Weather Advisories have been issued for the Lower MD Eastern Shore for the potential for 1-2" of snow.

- A brief period of light snow could amount to a few tenths of an inch of accumulation as far south as Richmond-Williamsburg.

Transient sfc high pressure has shifted offshore with weak SSW flow ahead of an approaching Arctic cold front (which is still over the Appalachians). A deep trough is located over the Great Lakes and Ontario, with a shortwave tracking over the Midwest at the base of the trough. It is milder than it has been with temps in the mid 40s- lower 50s this afternoon. The Arctic cold front approaches the area tonight and crosses the area from late tonight into Sunday AM.

The trough over the Great Lakes amplifies as it dives SE while the shortwave tracks across the Mid-Atlantic. The best forcing for ascent will miss us to our north. However, precipitation will enter far northern portions of the area after midnight, slowly spreading S/SE toward the I-64 corridor and lower Eastern Shore heading toward sunrise. S/SE progression continues through the morning before exiting offshore by early afternoon. Precip will likely last a few hours over the northern neck and eastern shore. While likely PoPs extend to the RIC Metro, precip will last 2 hours at most across the SW 2/3 of the area (including the RIC Metro and Hampton Roads). The most likely timing for precip is from 4-10 AM across the northern neck/eastern shore, 6-10 AM in the RIC Metro, and 8 AM-1 PM in SE VA/NE NC. With the Arctic FROPA, precip may very briefly begin as rain but will quickly change to snow in most areas outside of far SE VA/NE NC.

Still think that at least 0.1" is likely along and NE of a Richmond- Williamsburg line, with 0.5-1" expected across the northern neck, and 1-2" on the MD Eastern Shore. Could see a dusting in Hampton Roads if the changeover occurs in time. The coldest air won't arrive until Sun aftn/evening, so temps will only drop to 31-33F when the snow is falling. Therefore, accums will mainly be on grassy surfaces except on the MD Eastern Shore and perhaps the northern neck where snowfall rates may briefly reach 0.75"/hour. Have expended the Winter Wx Advisory to include all MD Eastern Shore counties. If snow lasts longer than expected, a "reasonable worst case" would be up to 3" in Dorchester/Wicomico and up to 2" for the rest of the Eastern Shore and Northern Neck.

Outside of precip chances, Sunday will be blustery as cold air rushes in behind the front. Winds will pick up by mid-morning Sunday and peak in the afternoon as the strongest CAA arrives. Gusts up to 35 mph are likely inland, with 45 mph gusts expected at the immediate Atlantic coast. With this in mind, have issued Wind Advisories for the VA Eastern Shore, VA Beach, and Eastern Currituck starting Sun aftn and continuing through Sun night. Highs range from the low 30s across the north to the low 40s in the SE, which will occur in the morning before temps drop in the afternoon. By mid- afternoon, wind chills could be as low as the mid teens.

SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/

As of 230 PM EST Saturday...

Key Messages:

- Cold Weather Advisories have been issued for the entire area for bitterly cold temps Sunday night/Monday morning with wind chills in the single digits.

- Chilly and dry Monday and Monday night with a slow moderating trend beginning on Tuesday.

Strong cold air advection continues Sunday night ushering in bitterly cold temperatures. Much of the area will see temps in the upper teens by midnight with Monday morning lows in the mid-teens for most of the area and the upper teens to around 20F close to the coast. While winds will not be quite as strong as Sunday night, there will be enough wind to knock wind chills down into the single digits for the entire area. Cold Weather Advisories have been issued for the entire area for consistent messaging, even though the lower 5F criteria may not be reached in all central VA/VA Piedmont zones as winds diminish Sun night. The only other thing to watch for is the potential for some light bay effect snow showers in Accomack/Northampton Counties with the cold NW flow. The ECMWF and the vast majority of its ensemble members continue to forecast 0.02- 0.04" of QPF over a decent portion of the VA Eastern Shore Sun night, while the other models (including the RGEM and CAMs which normally pick up on this type of thing) have no QPF with the LLVL flow a little bit more westerly. This is still low confidence but have added slight chc for snow showers to these zones to account for the possibility.

The Arctic sfc high slides in overhead Monday, leading to a cold and mostly sunny day with much less wind. Highs will be in the low to mid 30s. Not quite as cold on Monday night with lows in the low to mid 20s. A moderating trend begins on Tue as the high slides to our SE. Forecast highs are mainly in the upper 30s-mid 40s.

LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/

As of 230 PM EST Saturday...

Key Messages:

- Much warmer temperatures (compared to the first half of December) are on the way for the middle and end of the week.

- Another (weaker) cold front brings another chance for light rain Thursday night.

December 2025 has been one of the chilliest on record for many of our climate sites. However, quite the change is on the way for the extended period, with a pronounced warming trend continuing into the midweek period and likely peaking Thursday. The synoptic pattern will be characterized by rather progressive, quasi-zonal flow and building heights/thicknesses Tuesday night through Thursday. At the surface, transient high pressure is expected to remain offshore to our SE. All of this favors milder temps with high temperatures in the mid 50s by Wednesday. A warm front then lifts northward Thursday in advance of another cold front. There is some uncertainty regarding the exact progression of the warm front which will determine how warm temps get. For example, some guidance pushes the warm front through earlier Thursday. This would allow for mild temps areawide Thursday. On the other hand, another possible solution has the warm front lifting north in the evening and overnight Thursday. This would favor cooler temps Thursday, especially across the N. Regardless, it will likely be very mild (for December's standards) later Thursday and especially early Thursday night.

The cold front crosses the region Thursday night, bringing another chance for precip. At this time, QPF looks inconsequential (ensemble means are around a 0.25" or less). High pressure builds back in from the W Friday, settling over the area Saturday. While it likely temporarily trends cooler for the weekend, there are no signs of any additional significant cold air outbreaks.

AVIATION /00Z SUNDAY THROUGH THURSDAY/

As of 645 PM EST Saturday...

VFR conditions prevail at the start of the 00z/14 TAF period. High clouds and light 5 kt SW winds are expected for most of the night ahead of an Arctic front. The front will cross the terminals late tonight/early morning around 10-16z. A few hours of precipitation will likely accompany the front. A period of -RASN is likely at RIC/SBY changing to all snow with a couple hours worth of IFR VSBYs (best chc at SBY but an hour or so of IFR VSBYs is possible in -SN at RIC). Will note that LIFR VIS is possible at SBY with heavier snowfall. A rain/snow mix is expected at PHF/ORF, with mainly rain at ECG. In addition to the precip, CIGs will drop behind the front to IFR at all terminals before returning to dry and VFR conditions Sunday afternoon with terminals further west seeing clearing conditions first. Behind the front Sunday afternoon, NW winds will increase to 15-20 kt with gusts to 30-35 kt.

VFR conditions will prevail Sunday night through Wednesday. Gusty winds Sunday night into Monday morning near the coast will diminish on Monday.

MARINE

As of 230 PM EST Saturday...

Key Messages:

- A strong, Arctic cold front crosses the waters early Sunday morning, with Gale conditions expected later Sunday morning into Sunday night over all of the waters.

- Light freezing spray is possible Sunday night.

- Another round of SCAs is possible Monday night into early Tuesday.

A strong cold front is located NW of the region this afternoon, with high pressure now centered well offshore. In between these features, a weak warm front has shifted the winds to the S-SW. Regardless, marine conditions are generally benign with wind speeds 15 kt or less (highest northern coastal waters). Any elevated southerly flow diminishes across the N this evening into tonight, with SW winds 5- 10 kt for most of the night. Then, the strong front (of Arctic origin) drops southward through the waters after 09z/4 AM.

In the wake of the strong cold front early Sunday morning, very cold and dry air advects into the region. Extremely cold temperatures aloft (850 mb temps as low as -20 C) mix down to the surface across (relatively) warmer waters, creating very windy conditions. Winds rapidly increase and become NW Sunday morning, with sustained winds of 25 to 30 knots and gusts of 35+ knots expected by late morning- early afternoon over a majority of the waters. Winds increase further during the afternoon-evening hours, peaking between roughly ~00z to 06z Monday (7 PM Sun to 1 AM Mon); sustained winds of 30 to 35 knots and gusts up to 45 knots are expected during this timeframe. Given the extreme airmass change, would not be surprised if brief storm-force wind gusts were realized, especially at the elevated observation sites. Gale Warnings are in effect for all zones starting early Sunday morning.Winds should fall below Gale thresholds everywhere by sunrise Monday morning, and then below SCA thresholds by Monday afternoon, as high pressure builds back into the area.

In addition to the wind, seas build to 6 to 10 feet by Sunday night, though the slight offshore component of the wind should help to keep seas from building further. Waves in the Chesapeake Bay will build to 4 to 6 feet. Finally, some freezing spray is possible Sunday night due to the strong winds and cold air temperatures. However, marginal water temperatures (low to mid 40s) should keep any freezing spray light. Thus, will keep mention of this out of the text forecast for now.

Calmer conditions are anticipated later Monday, though a brief surge of S-SW wind may lead to additional SCA headlines (mainly over the Chesapeake Bay) late Monday night into early Tuesday morning. Sub- SCA conditions then return Tuesday into Wednesday. Another cold front may bring increasing winds Thursday into Friday.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...Winter Weather Advisory from 1 AM to 1 PM EST Sunday for MDZ021>025. Cold Weather Advisory from 7 PM Sunday to 9 AM EST Monday for MDZ021>025. NC...Cold Weather Advisory from 7 PM Sunday to 9 AM EST Monday for NCZ012>017-030>032-102. Wind Advisory from 1 PM Sunday to 7 AM EST Monday for NCZ102. VA...Cold Weather Advisory from 7 PM Sunday to 9 AM EST Monday for VAZ048-060>062-064>069-075>090-092-093-095>100-509>525. Wind Advisory from 1 PM Sunday to 7 AM EST Monday for VAZ098>100. MARINE...Gale Warning from 4 AM Sunday to 7 AM EST Monday for ANZ630- 631. Gale Warning from 7 AM Sunday to 7 AM EST Monday for ANZ632- 634-650-652-654. Gale Warning from 10 AM Sunday to 7 AM EST Monday for ANZ633- 635>638-656-658.