textproduct: Wilmington

SYNOPSIS

A low pressure system will impact the Ohio Valley this weekend. This system will bring a chance for rain and snow, mainly during the day on Sunday. Seasonably cold temperatures will continue through much of next week, with multiple systems impacting the region during the mid to late week period.

NEAR TERM /THROUGH TONIGHT/

Lower stratus clouds from the southern system will push east of our fa later this morning. However, clouds are already beginning to build in from the west ahead of a Clipper system. While we are not anticipating any accumulating precip today, there will be an H5 shortwave that ejects through the region during the daytime. With this subtle forcing, CAMs do try to initialize some light precip. Based on bufkit soundings, any precip will likely remain in the form of snow flurries, primarily north of the OH River.

Temperatures will trend a couple degrees warmer today compared to Friday, but still remaining below seasonal normals as highs top off in the 30s.

SHORT TERM /SUNDAY/

Forecast on track to remain dry through the majority of the night. Thicker cloud coverage will prevent temps from plummeting overnight, with lows expected to remain in the middle 20s to near 30.

Main feature to monitor for Sunday is the progression of a Clipper system. Latest 00z model runs have backed off on overall QPF footprint in our CWA, along with suggesting a more northerly surge in warmer air in the low levels. In turn, this has lowered the threat of accumulating snowfall for a large portion of our CWA. Most of the accumulating snow potential is now confined to counties north of the I-70 corridor, primarily in west-central OH. Latest trends would suggest that snow accums would now be half an inch or less for our northern counties, with ~1 inch being the high end (which would likely be confined to Mercer, Auglaize and Hardin counties).

Additionally, with snowfall occurring primarily during the daytime hours, pavement temps should be warm enough to limit travel impacts. This is also supported by the probabilistic WSSI, which shows 0% probabilities of observing minor winter travel impacts from this system. Thus, went ahead and removed any HWO mention for snow given the lack of impacts.

LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/

The weekend shortwave will be moving off to the east at the start of the extended, being replaced by a robust 1032 surface high. This gives us a reinforcing show of cold air and Sunday's overnight lows fall into the single digits in west central Ohio and teens elsewhere, while Monday's daytime highs only reach mid 20s to low 30s. Similarly, Monday overnight lows once again fall to the teens. Fortunately, thanks to the surface high, winds should be relatively light, so additional wind chill factor shouldn't be too much of an issue. Even so, quite a cold start to the week.

Looking beyond Monday, the surface high is shunted eastward as two fast moving Clipper systems race toward the Great Lakes region. The first of the two moves through Monday night/Tuesday with the majority of guidance keeping the track of this system well north of our area. This really limits the overall QPF from this first wave, though cannot rule out some passing light snow showers in our very far north (Mercer, Auglaize, Hardin and north). The pressure gradient tightens with the passage of this feature, resulting in some breezy conditions at the surface, particularly north of I-70.

The second Clipper system Tuesday night/ Wednesday will be a bit more robust, as guidance suggests it deepening as it digs into the larger flow over the Great Lakes. A pretty potent LLJ and tightened gradient will also move through the region with this wave, resulting in gusty conditions on Wednesday. Recent trends have shifted the track of this feature farther north, placing the ILN CWA more comfortably in the warm sector, resulting in a more rain solution across the region. However, would not rule out some snow showers on the back end of the system sometime Wednesday night on Thursday.

Strong cold air advection moves in on the back end of this system and end of week temperatures look to once again fall well below seasonal normals.

AVIATION /12Z SATURDAY THROUGH WEDNESDAY/

Brief IFR conditions possible at KCVG and KILN early this morning. Otherwise, VFR conditions will be brief elsewhere as an MVFR deck will build in from the west and likely persist through the remainder of the taf period. CIGs may drop to <2000 ft by the afternoon, with highest confidence at our northern terminals.

While the forecast is expected to remain dry through this taf period, some snow flurries will be possible. Better chances for precipitation arrive on Sunday, but in general, precip will remain light.

Stronger winds advecting in from the southwest will result in sustained winds around 10 kts or so during the daytime.

OUTLOOK...MVFR to IFR CIGs possible into Sunday and again on Wednesday.

ILN WATCHES/WARNINGS/ADVISORIES

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