textproduct: Wakefield

WHAT HAS CHANGED

Some snowfall remains possible Sunday, though a drier and quicker- moving system is now favored. Otherwise, no significant changes.

KEY MESSAGES

1) Cold and dry today, followed by milder temperatures Saturday. There remains a chance for light rain or a rain/snow mix early Saturday in the Piedmont.

2) Wintry precip remains possible Sunday, though trends have been favoring a drier system. The best chance for any (light) snowfall accumulation is away from the coast.

3) 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 545 AM EST Friday...

KEY MESSAGE 1...Cold and dry today, followed by milder temperatures Saturday. There remains a chance for light rain or a rain/snow mix early Saturday in the Piedmont.

Cold temperatures are in place across our forecast area this morning. The cold front that passed through yesterday morning is now well offshore, with high pressure southwest of the region. A light breeze is also contributing to wind chills in the teens and these could bottom out in the 10-15 F range this morning, locally cooler NW of Richmond.

For the rest of today, the high pressure system to our south will quickly translate offshore of the Southeast CONUS as low pressure moves through the Great Lakes region. This will allow the low-level flow to shift to the S-SW by this afternoon, becoming breezy with occasional gusts to 20-25 mph. While temps may be a couple degrees higher than Thursday, it will still be quite chilly with highs in the lower-mid 40s and potentially only the upper 30s across the far northern tier of our CWA. Clouds increase tonight as the first in a series of cold fronts approaches the area. Low temps look to be quite a bit warmer, only dropping into the lower 30s.

A large UL trough over the central CONUS pivots/translates toward the eastern US Saturday. That cold front discussed above will slowly inch into the area, but generally washes out over the Piedmont. Most model guidance has some sort of light precip riding along the frontal boundary earlier Saturday, but the most favorable upper forcing and moisture will track through the Appalachia region into the interior Northeast. This light precip could briefly start out as snow or rain/snow mix for a few hours either side of sunrise, again mainly for NW portions of our area. Given highly marginal temps and light rates, do not expect any accumulation or impacts. Highs Saturday will remain stuck in the 40s across the NW, with 50s increasingly likely further SE. Lower 60s are even possible for far SE VA and NE NC.

KEY MESSAGE 2... Wintry precip remains possible Sunday, though trends have been favoring a drier system. The best chance for any (light) snowfall accumulation is away from the coast.

A deep trough will dig from the Plains into the Deep South Saturday night into Sunday. This will trigger some sort of (weak) cyclogenesis along a remnant frontal boundary near the Southeast coast. Moisture still looks to be drawn northeastward toward our area Sunday, but there remains quite a bit of spread in the model guidance on the degree and placement of precip coverage. Overall, the trend has been for a flatter and more progressive upper-level pattern, allowing any weak sfc low to quickly slide out to sea. Any precip would therefore be quite brief and generally confined to eastern portions of the area. The blended guidance continues highlight the highest PoPs for SE VA and NE NC and this seems appropriate based on all available data. However, PoPs in the I-95 corridor and points W may end up being too high with a decent portion of the guidance now mostly dry out in these areas.

Obviously, the other focus will be any potential wintry precip. The location of the high (south and west of the region) is not favorable for a sustained supply of cold air. Furthermore, the more appreciable colder air looks to usher in after most of the precip departs. The current forecast has precip starting out as rain or rain/snow mix for the first part of Sunday, transitioning to all snow (away from the coast) through the day as the column cools. Given the aforementioned cold air issues, think there is a very decent chance that coastal Hampton Roads and NE NC stay all rain through most of this event, with only low probs for snow. Regarding snow amounts, the GEFS highlights the highest probs for >1" from the RIC metro into the Northern Neck and Eastern Shore, while the EPS favors areas near the coast (especially Eastern Shore) for this. All of this assumes a 10:1 ratio which may be very generous near the coast if temps are only 33-35 F. Probs for >3" have decreased and are generally 10% or less. Furthermore, the hi-res guidance has also been trending lower with totals. Our storm total snow forecast generally highlights up to an inch for most of the area with the best potential for >1" from the Northern Neck to the upper Eastern Shore. In summary, while some snow is likely Sunday, trends have been for a drier and quicker-moving system with less cold air. Certainly could see further adjustments over the next few forecast cycles but this continues to not look like a major and/or impactful event.

KEY MESSAGE 3...Another surge of Arctic air arrives for early next week, with below normal temperatures to continue through the first half of next week.

Arctic air is likely on the way behind Sunday's system. Frigid temperatures are expected for at least the first half of next week. Overnight lows in the teens are expected Sun night-Tues night. Cold Weather Advisories are possible Mon night given forecast wind chills in the single digits across the N and W. While day-time temps will be rather chilly each day, Tues looks to be the coldest day with highs struggling to make it above freezing.

Temps may attempt to moderate a bit by the middle and end of the week as the upper flow turns more zonal.

AVIATION /12Z FRIDAY THROUGH TUESDAY/

As of 545 AM EST Friday...

VFR is expected through the 12z TAF period. Primarily SKC is forecast but SCT mid-level clouds are likely this afternoon at RIC and potentially SBY. W winds this morning will shift to the SW this afternoon and then S tonight, with speeds generally 8-12 kt. Gusts up to 20 kt are expected at SBY through the early afternoon. A period of LLWS is also forecast after 04z or so as a low-level jet develops and have included mention of this in the RIC, SBY, PHF, and ORF TAFs.

Outlook: High-end MVFR CIGs are possible Saturday as a cold front approaches. Rain or a rain/snow mix is also possible earlier Saturday in the Piedmont, but should remain NW of all terminals. More widespread flight restrictions are anticipated by Sunday as rain, and likely some snow as well, overspread the region.

MARINE

As of 200 AM EST Friday...

Key Messages:

- Gale Warnings and Small Craft Advisories are in effect this morning as strong NW winds continue.

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

Early this morning, seeing another surge of drier/colder air over the waters as high pressure builds south of the local area. Winds are out of the NW, ranging from 15 to 25 knots with gusts to 30 knots (35 knots over the northern coastal waters). Small Craft Advisories remain in effect until 7 AM EST this morning and a Gale Warning remains in effect until 7 AM EST for the northern coastal waters. Winds diminish later this morning through this afternoon as high pressure builds south of the area. The lull in winds will be brief however, as high pressure quickly moves offshore and a low pressure system moves through the Great Lakes. This will allow for winds to shift to the SW this afternoon, and increase this evening into tonight. Another round of SCAs will likely be needed for at least the Chesapeake Bay and the northern half of the coastal waters. Winds gradually subside below SCA levels by late morning- early afternoon Saturday. Winds become N to NW Saturday night as another cold front moves through the area, but winds are expected to remain sub-SCA at this time. The next potential for SCA conditions will be Monday into Tuesday as another strong front moves over the waters. Seas generally range from 3 to 5 feet, subsiding to 2 to 3 feet this afternoon. Seas build again to 3 to 5 feet tonight into Saturday morning due to the increasing SW winds.

Low water conditions are still possible tonight into Saturday in the lower Chesapeake Bay, James/York Rivers, and near the coast of the Atlantic waters. While guidance continues to trend 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...None. VA...None. MARINE...Small Craft Advisory until 7 AM EST this morning for ANZ630>634-638-654-656-658. Gale Warning until 7 AM EST this morning for ANZ650-652.