textproduct: Wilmington

SYNOPSIS

A strong system will move through today bringing with it a transition from rain to snow showers, gusty winds, and cooler temperatures. A couple of systems Thursday night into Friday morning and Saturday into Saturday night are both expected to bring accumulating snow to the region. Very cold air will filter in bringing near or below zero wind chill values both Sunday and Monday morning.

NEAR TERM /THROUGH TONIGHT/

A gap in precip behind an enhanced band with wind gusts from 30-40kts currently near KCMH to just east of KLUK. Falling temperatures working into the forecast area, with a rain/snow shower mix with wind gusts to 35kts in the cold air advection wrap around moisture. Wind gusts 30-35kts are more likely now behind the main frontal boundary, with a changeover to all snow showers after 4pm working east through the area. Moisture does diminish pretty quickly, but still the potential for a very light coating of a tenth or two of snow especially on elevated surfaces as the evening progresses. Continued the SPS for winds and slick surfaces through 00z for now, as well as expecting to continue mention of these in the HWO.

Strong CAA and diminishing wind gusts overnight under cloudy skies as the upper trough pivots through the region. Overnight lows in the lower 20s north to upper 20s south. Moisture becomes more sparse overnight, so snow showers will diminish in coverage. Wind gusts will diminish overnight, but winds remain slightly elevated near 10mph.

SHORT TERM /THURSDAY THROUGH FRIDAY/

A brief lull in precip expected on Thursday, though per several of the CAMs, continued with at least a slight chance of snow showers in central Ohio in NW flow bringing a fetch off of Lake Michigan. With the continued NW flow/strong CAA, much below normal daytime highs in the upper 20s to lower 30s.

For Thursday night, chance for snow ramps up especially near/after midnight in eastern Indiana, exiting the area near/after 15z, with the prime accumulation potential time from ~06z-12z. The best area of moisture of 0.2-0.3" is expected generally across SE Indiana through the Cincinnati Tri state and eastward to the lower Scioto valley, which has shifted the probability of exceeding both 1" and 2" of snow a little further south, with prime location extending from near Richmond, IN and southeast toward Hamilton/Cincinnati Ohio and into far northern KY. This remains the prime area with the greatest probability of 2"+ of snow accumulation by 15z.

Lesser chances of these thresholds occurring in Central Ohio. The system is fairly progressive, and some slight downward adjustments made from the NBM SLRs to a little closer to the WPC SLRs, generally 11-13:1 across the south, and 13-16:1 closer to I-70. The resulting snow potential will have a pretty tight gradient across the region. Another possibility/uncertainty which could cut a bit into snow totals across the south is a warm air push beginning near 12z, with temperatures rising through the mid 30s across the south in the 12-17z timeframe. So a mix with or complete changeover to rain is possible as the core area of precip is winding down/heading east.

Bulk of the accumulating snowfall will shift eastward after 15z Friday, with colder/dry air funneling into the Ohio Valley for the weekend, with high confidence in these bitterly cold temperatures.

LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/

A brief period of cold and dry weather is expected from Friday night through Saturday morning before the next system arrives later on Saturday.

By the second half of Saturday, an arctic front and upper level disturbance will be diving toward the Ohio Valley from the northwest. Just ahead of these features, an area of snow develops and moves across the area starting Saturday afternoon/evening before pulling east by Sunday morning. A widespread 1-3 inches are moderately likely although the heaviest axis of snow has yet to be resolved. There are also some indications that snow rates and ratios could be fairly high north of I-70 with vorticity max moving in along with the arctic boundary.

Bitterly cold air settles in from Saturday night through Monday morning. Overnight lows drop into the single digits for many locations along with wind chills below zero Sunday and Monday mornings. High struggle to get out of the teens.

Temperatures moderate to start next week.

AVIATION /18Z WEDNESDAY THROUGH SUNDAY/

Visibility restricting rain pushing east of all of the TAF locations, with gusts from 25-35kts possible through about 22z before slowly diminishing. After a lull in precipitation, wrap around moisture in the form of RASN to work eastward and gradually change over to all -SHSN. Have generally handled this as tempo MVFR visibility restrictions especially from 20-04z, with Prob30 MVFR visibility restrictions in lingering snow showers to about 06-08z. Cigs will generally be MVFR, with occasional IFR possible in snow showers.

After 12z, while snow showers may linger toward KCMH/KLCK, probability is pretty low for vsby restrictions at this time. Lingering MVFR CIGs possible through the period.

OUTLOOK...MVFR to IFR conditions possible Thursday night through Saturday night.

ILN WATCHES/WARNINGS/ADVISORIES

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