textproduct: Wakefield

WHAT HAS CHANGED

Temperatures have been lowered slightly for this afternoon/tonight.

Gale Watch was converted to a Gale Warning north of Parramore Island, and converted to a Small Craft Advisory farther south.

KEY MESSAGES

1) A strong cold front crosses the area this morning. W to NW winds become gusty today into this evening in the wake of the front, gusting to 30 to 35 mph.

2) Colder but mainly dry through Friday. Wind chill values in the teens are forecast late tonight. There is a low-end chance for some light precipitation on Saturday, mainly across the VA piedmont.

3) Low pressure develops off the Southeast coast over the weekend, with the potential for wintry precip across portions of the area on Sunday. Uncertainty remains very high regarding specific impacts.

4) Another surge of Arctic air arrives for early next week, with below normal temperatures to continue through the first half of next week.

DISCUSSION

As of 455 AM EST Thursday...

KEY MESSAGE 1...A strong cold front crosses the area early this morning. W to NW winds become gusty today into tonight in the wake of the front, with increasingly efficient mixing in CAA allowing winds to gust to 30 to 35 mph. Winds diminishing late tonight into early Friday, as cold high pressure builds to the SSW.

Yet another shortwave embedded within the potent northern stream trough is lifting through the mid-Atlantic region this morning. This system and its attendant strong surface cold front will be lifting across the local area in the next 2-3 hours. Winds remain SSW along the coast, but have veered around to the W-NW along and west of I-95 portion of the area as of this writing. Temps remain nearly steady until the front crosses into the area. Thereafter, strong CAA post-frontal drives temps down into the upper 30s/lower 40s, with highs likely to be achieved this morning over much of the area. Dewpoints also drop quite a bit behind the front, likely reaching the single digits inland during peak mixing.

KEY MESSAGE 2... Colder but mainly dry through Friday. Wind chill values in the teens are forecast late tonight. There is a low-end chance for some light precipitation on Saturday, mainly across the VA piedmont.

Given diminishing winds, clear sky and the cold, dry airmass building into the region, went a bit below NBM for lows. Look for lows tonight in the upper teens to lower 20s inland, low to mid 20s along the coast. Wind chill values are expected to drop into the mid teens late tonight. While this is near but just above Cold Weather Advisory thresholds, it's certainly noteworthy given the recent mild temperatures.

High pressure moves offshore on Friday, but temperatures remain on the chilly side in the upper 30s to mid 40s. Not quite as cold on Saturday ahead of the next Arctic front, with highs ranging from the mid 40s NW to the upper 50s SE. There is a slight chance for some rain showers (some light snow mixing in across the NW half of the area) but moisture is limited as the shortwave is dampening as it crosses the southern Appalachians Sat morning. Turning cold once again Saturday night with lows in the mid 20s to low 30s.

KEY MESSAGE 3...Low pressure develops off the Southeast coast over the weekend, with the potential for wintry precip across portions of the area on Sunday. Uncertainty remains very high regarding specific impacts.

Attention then turns to Sunday, as a deep trough digs south from the mid-south toward the central Gulf Coast. Surface low pressure forms off the SE coast Sunday morning and lifts NE. 00z/15 guidance has mainly continued the trend of the past few cycles, favoring a stronger surface low closer to the coast, along with a slower/less progressive upper pattern. The 00z GFS and its ensembles remain the slowest with the shortwave, which results in it being most bullish/aggressive with snow totals, as the system takes a neg tilt earlier, allowing for more plentiful snow totals. 00z GEFS probabilities have accordingly increased to 50-80+% for impactful/accumulating snowfall AOA 1" across most of our area (except immediate NE NC coast), highest across inland sections, but its 3+" probs are still low. The ECMWF and EPS are not quite as slow as the GFS, but is farther east with the vorticity max at present, and hence farther offshore with the low and more suppressed with snows. Specifically, EPS 00z snow probs for 1" are lower than GEFS (40-60%+) but have also trended a bit farther east/offshore and are accordingly focused across the Hampton Roads area into NE NC. The chance for at least 3" is still quite low...only about 20%...but is again focused primarily over Hampton Roads and the eastern Carolinas, with little or no snow inland. Much of the remainder of the guidance is more progressive, with precip focused mainly along the coast and offshore.

Given the large model spread, it's still just too early to make any definitive specifics, let alone throwing out snow totals. There are many moving parts to this portion of the forecast, including but not limited to the evolution and orientation of the upper system, the exact track/trend of the attendant surface low, and the presence or absence of an upstream shortwave that, if present, could quicken the upper pattern and shorten the window for potential snows. In short, users are encouraged to stay up to date with the latest forecasts over the coming day or two, as the specifics of each of these elements are likely to become more evident.

KEY MESSAGE 4...Another surge of Arctic air arrives for early next week, with below normal temperatures to persist through the first half of next week.

Regardless of the exact evolution of the weekend system, another reinforcing shot of Arctic air arrives on its heels Monday into Monday afternoon, sending another surge of cold Arctic air back into the region. Below normal temperatures are expected to linger through the middle of next week, with lows in the teens and 20s and highs in the 30s, or ~1 to 1.5 standard deviations below normal for mid-January.

AVIATION /18Z THURSDAY THROUGH TUESDAY/

As of 1225 PM EST Thursday...

VFR conditions are expected to prevail through the 18z TAF period. The cold front has cleared all terminals with gusty WNW winds in its wake. Gusts are mainly 20-25 kt but could see a few stronger gusts at SBY and ORF. Skies are clear outside of a few lingering clouds near ECG that should move offshore in the next hour or two. Remaining somewhat breezy tonight, especially near the coast. Winds become SW 5-10 kt on Friday.

Outlook: VFR conditions are expected Fri night with some potential for MVFR CIGs on Sat. Cannot rule out a few rain or snow showers Sat morning, mainly across the Piedmont. Another system approaches the region Saturday night and potentially impacts the region on Sunday with snow or a rain/snow mix and flight restrictions possible.

MARINE

As of 245 AM EST Thursday...

Key Messages:

- Gale Warnings and Small Craft Advisories are in effect through Friday morning as winds become westerly behind a strong cold front today.

- Elevated SW winds and likely SCA conditions return Friday night into Saturday morning.

- Low water conditions remain possible in the lower Chesapeake Bay, York/James Rivers, and along the coast of the Atlantic waters during low tide Friday night into Saturday.

A strong cold front is approaching the waters this morning. As of 2 AM, winds remain SW 10-20 kt. However, the wind direction will abruptly shift to the W over the next few hours as the front pushes through. Wind speeds increase to 15-25 kt with gusts to 30 kt through most of today. While sporadic higher gusts are possible along the immediate frontal passage this morning, prevailing winds remain sub-Gale for all waters through the evening. Stronger cold advection arrives tonight and very efficient mixing will likely lead to a period of frequent ~35 kt gusts on the northern coastal waters. Elsewhere, wind gusts should stay closer to 30 kt, but cannot rule out occasional 35 kt gusts (best chance for this would be in the Chesapeake Bay N of Windmill Pt). Small Craft Advisories remain in effect for all waters through Friday morning, with Gale Warnings now in effect from 00z-12z Fri (7 PM today-7 AM Fri) for the ocean N of Parramore Island. The lull in the winds looks brief Friday as high pressure quickly offshore and a low pressure system moves through the Great Lakes. This will allow for winds to shift back to the SW by Friday afternoon and another round of SCA conditions are likely Friday evening and overnight as a belt of stronger winds aloft overspread the area. Winds remain elevated into Saturday morning before subsiding to sub-SCA levels by the afternoon hours. There is decent confidence in a wind shift to the N-NW Saturday night as a cold front drops through, but uncertainty quickly increases by Sunday-Monday as low pressure may develop and ride along the remnant frontal boundary. A closer/stronger low would lead to higher winds while a weaker/suppressed system would have weaker winds. At this time, at least marginal SCAs appear probable. Will continue to monitor.

Seas remain in the 3-5 ft range through Friday morning with some potential for 6 ft seas out 20 nm on the ocean tonight. Seas then briefly subside to 2-3 ft Friday before increasing again to 3-5 ft Friday night and Saturday morning with the SW wind increase.

Low water conditions are still possible Friday night into Saturday in the lower Chesapeake Bay, James/York Rivers, and near the coast of the Atlantic waters. While guidance has trended a bit higher with the water levels, there is still potential for -1 to -1.5 ft MLLW readings and resultant Low Water Advisories.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...INCREASED FIRE DANGER until 5 PM EST this afternoon for NCZ012>017-030>032. VA...None. MARINE...Small Craft Advisory until 7 AM EST Friday for ANZ630>634-638- 654-656-658. Small Craft Advisory until 4 AM EST Friday for ANZ635>637. Small Craft Advisory until 7 PM EST this evening for ANZ650- 652. Gale Warning from 7 PM this evening to 7 AM EST Friday for ANZ650-652.