textproduct: Wilmington

SYNOPSIS

Brisk and cold conditions will continue overnight into Thanksgiving. Surface high pressure will offer dry weather and less wind for Friday. Low pressure will provide impactful weather this weekend with a wintry mix Saturday and Sunday.

NEAR TERM /THROUGH THURSDAY/

Quick update with the expiration of the wind advisory effective as of 10PM. Still seeing some 30-40 MPH gusts and expecting this will continue for another few hours.

Previous discussion 758PM > Wind advisory remains in effect for the northern half of the forecast area through 10PM. The 00Z KILN sounding confirms what was suggested by model soundings -- the boundary layer remains well- mixed, even after sunset. This is contributing to winds remaining gusty this evening, and based on recent model data, it is expected that winds will take a while to begin to subside. Wind gusts in the forecast were increased somewhat through about 08Z. Indeed, a few observation sites (including KILN, KDAY, KI95, and KVTA) have had gusts above the 40kt advisory criteria within just the past 90 minutes.

Some patchy flurries are also moving through the area, but these should be off to the east by 06Z.

Previous discussion 108 PM > Deep stacked low to migrate slowly east through the northern Great Lakes this evening and into southeast Canada overnight. In the wake of an associated strong cold front - CAA, cyclonic flow, and a tight pressure gradient was leading to clouds and strong winds. West wind gusts of 40-45 mph have been observed but have not peaked yet and expect max wind gusts up to 50 mph - with the highest gusts across west central Ohio. Winds will diminish overnight some but will still remain close to 20 mph. Will continue the wind advisory across the north through 10 PM. Clouds look to hang tough thru the evening and then begin to decrease across the southwest late. Cold temperatures drop to lows in the mid and upper 20s.

SHORT TERM /THURSDAY NIGHT THROUGH 6 PM THURSDAY/

Amplified mid level flow with a ridge over the west and long wave trough over the eastern CONUS. Skies look to vary from a good amount of sunshine over the southwest to considerable cloudiness across the far north-northeast where cyclonic flow and fetch off the lakes will lead to more clouds. Brisk west winds 15-20 mph will continue through Thursday, with highs temperatures ranging from the lower 30s far north to the upper 30s south of the Ohio River.

An embedded shortwave and flow off the Lakes may lead to a few snow showers far north - Thursday night with continued cloud cover. The remainder of the area should see mostly clear to partly clouds skies. Cold temperatures drop to lows in the lower 20s in most locations with mid 20s in the urban locations.

LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/

A strong (1032) surface high will be pushing east into the Ohio Valley region from the Plains at the start of the extended. This results in quiet weather on Friday with decreasing cloud cover. As this feature shifts east by Friday night, clear skies and light winds will result in strong radiational cooling. Right now, overnight lows are forecast in the teens, but these may need to be tweaked lower as we get closer. Saturday morning arrives dry, though with cloud cover increasing ahead of the next disturbance....

All eyes will be on a rather robust system that is poised to impact the region this holiday weekend. A deepening shortwave to the west of the Great Lakes will bring a mix of rain and snow, in addition to renewed breezy conditions, to the region on Saturday into Sunday.

Extended guidance remains muddled on the details concerning placement of the low and how quickly the residual surface high can be punted off to the east. Current thinking is that initial p-type will be all snow Saturday afternoon/evening, quickly transitioning to a mix and then to all rain as we head into the overnight hours into Sunday morning. As cold air wraps around on the backside of the low, a transition back to a wintry mix or even all snow on Sunday is possible.

The ECMWF ensemble continues to run with a warmer solution that holds onto the surface high longer, however, recent trends have shifted the center of the low farther south, somewhat limiting the extent the warm sector is able to expand into the Ohio Valley. Meanwhile, the GFS and Canadian ensembles both are trending toward a colder solution with a quicker shift of the high. Either way, trends indicate that a subtle bump up in snow totals was warranted. For now, have around 2 inches in east central IN/ west central OH with a quick taper down to 0.25" closer to Columbus. However, this is a VERY early deterministic guess. For what it's worth, ensemble plumes have an average closer to 0.5 inch in Columbus... this tells us that there is still quite a bit of spread in solutions and not to hang your hat on any totals this far out!

After the cold front is pulled through on Sunday, we'll have a non- diurnal temperature drop and temperatures will plummet throughout the daytime hours. By Sunday night, forecast temps fall into the 20s, possibly even teens in west central Ohio. With the continued breezy conditions, feels like temperatures will be comfortably in the teens. Cover up exposed skin if you're planning to be outside.

Weak surface high pressure moves in across the Great Lakes on Monday behind the low, resulting in mostly dry conditions across the region. Low end PoPs linger across the southern portion of the CWA, where the surface high's influence isn't as strong, however, confidence on Pops vs no PoPs this far out when very weak forcing is present isn't robust.

Looking out further in time, ensembles do hint at yet another system to work through, so we should remain active the first week of December.

AVIATION /03Z THURSDAY THROUGH MONDAY/

Winds remain the biggest issue to discuss through the TAF period, and especially through the next few hours. Westerly winds of 15-20 knots, with gusts of 30-35 knots, will continue through the next few hours. Although it is after sunset, the winds are not expected to quickly drop off, and the TAFs indicate that gusts will continue through the overnight hours.

Some very light precipitation has been working its way through the area, with only some very minor impacts to visibilities possible.

Ceilings are expected to remain VFR through much of the period, but some patches of MVFR will probably develop around 12Z. This has been included in some of the TAFs with a TEMPO group. Otherwise, winds tomorrow will have some 20-25 knot gusts, but conditions will be VFR.

OUTLOOK...No significant weather expected.

ILN WATCHES/WARNINGS/ADVISORIES

OH...None. KY...None. IN...None.