textproduct: Wilmington

SYNOPSIS

Brisk and cold conditions will settle into the region through the end of the workweek, with mainly dry conditions through Friday. A wintry mix of precipitation is likely late Saturday into early Sunday as a system moves through the Ohio Valley. Below normal temperatures are expected to evolve into early next week.

NEAR TERM /UNTIL 6 PM THIS EVENING/

With very steep lapse rates being maintained across the region (as sampled on the 27.00Z KILN RAOB), gusts to 30kts will continue through the next few hours before slowly subsiding toward daybreak and beyond. Gusts to around 25kts will persist through the daytime as the pressure gradient remains somewhat tight and lapse rates remain steep.

Large-scale cyclonic flow will continue in the Great Lakes/Ohio Valley regions through the daytime today, with mostly cloudy conditions expected as LL moisture pivots around the broad low center. A bit more sunshine can be expected near/south of the Ohio River, although it will be filtered as some thick cirrus overspreads the area.

Although the moisture within the LL cloud-bearing layer will be somewhat shallow in nature, suppose a few flurries cannot be ruled out from time-to-time this afternoon, particularly near/N of I-70 into central OH where moisture availability off the lakes will be a bit more robust. A subtle trof axis will pivot through the region this evening into early tonight, which may provide just enough forcing for some scattered flurries this evening from WC through central OH.

Highs today will be about 10-12 degrees below normal, generally topping out in the mid to upper 30s.

SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/

ISO/SCT lake enhanced/effect SHSN and light flurries will be possible this evening through tonight, especially from WC through central OH, as a subtle trof axis pivots through the region, providing just enough forcing for some ISO/SCT activity near/N of I-70. Temps will dip into the lower to mid 20s through tonight as even colder air settles into the region.

Expansive cloud cover will persist near/N of I-70 through tonight, with some of this better cloud cover expected to drift to the S toward daybreak Friday. Some clearing will evolve into Friday afternoon in the Tri-State and N KY, but mostly cloudy to OVC skies should be maintained from WC through central OH through much of the daytime.

With a reinforcing shot of cold air into early Friday, highs on Friday will top out in the lower to mid 30s from N to S, respectively. Daytime highs around freezing are expected for most spots N of the OH Rvr.

LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/

Friday night remains quiet as a cold surface high shifts east of the Ohio Valley. Temperatures are expected to drop into the lower 20s/ upper teens which sets up an interesting day for Saturday.

On Saturday, a couple upper level shortwave troughs eject out of the Plains into the Mississippi River Valley. A primary surface low is forecast to form around the middle Mississippi River Valley by midday as the upper level waves consolidate. The deepening low moves northeast Saturday afternoon toward the Great Lakes. This low and associated upper level trough bring precipitation into the Ohio Valley by Saturday afternoon/evening. Precipitation is likely to start as snow since cold air will still be in place as the high recedes. Some accumulations and travel impacts are possible and looking increasingly likely Saturday afternoon and evening.

The low then continues to progress northeast through the Great Lakes on Saturday night and Sunday morning. This is when forecast uncertainty over the Ohio Valley grows substantially. While precipitation is likely to be ongoing, increasingly warm air keeps advecting in from the south. A warming profile should eventually support a changeover from snow towards overnight and into Sunday morning especially southeast of I-71. However, mesoscale guidance is still just a bit too far out of range to be of use just yet. Thermal profiles are borderline so a small change in temperatures will have a large impact of rain vs snow. If snow ends up being the favored precipitation type, larger travel impacts could linger into Sunday. The best chance for travel impacts is along and especially northwest of I-71 where temperatures remain closer to freezing. Precipitation ends Sunday evening after a cold front pushes through the area. Cold temperatures remain in place through the start of next week.

The next chance for possible winter weather develops in the Monday night to Tuesday night timeframe. An upper level trough moves through the Ohio Valley which could lead to some light snowfall. There is also the outside chance a surface low develops close enough to the area to provide some possible impacts.

AVIATION /12Z THURSDAY THROUGH MONDAY/

Westerly winds of 12-15kts, with gusts 20-25kts, will be maintained through the TAF period.

A borderline MVFR/VFR cloud deck is expanding across the area, with MVFR CIGs possible for several hours early/mid morning just about anywhere. However, some scattering/clearing will evolve for the afternoon for srn sites, with VFR CIGs likely persisting for nrn sites of KDAY/KCMH/KLCK through the period. Where these CIGs are able to be maintained toward/past 00z, some flurries or brief light SHSN will be possible, so have added a PROB30 at KCMH/KLCK to account for this potential.

OUTLOOK...MVFR/IFR CIGs and VSBY with wintry precipitation is likely late Saturday into early Sunday. LIFR CIGs and VSBY will be possible during this time.

ILN WATCHES/WARNINGS/ADVISORIES

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