textproduct: Wilmington

WHAT HAS CHANGED

Increased chances for wintry precipitation Sunday into Monday.

KEY MESSAGES

1) Light snow possible this morning.

2) Potential for wintry precipitation early next week.

DISCUSSION

KEY MESSAGE 1) Light snow possible this morning.

A weak shortwave will move east into the area this morning. This wave is currently producing some precipitation over Illinois, and precipitation is expected to move through the ILN forecast area during the 08Z-14Z time frame. Some light radar echoes currently over Indiana are likely virga, with saturation still underway before precipitation is more likely to reach the ground. With marginal temperatures on either side of freezing, precipitation that occurs in the ILN CWA may be a mix of rain and snow, with snow favored in a swath from eastern Indiana through southern Ohio, and rain favored for southeast Indiana and northern Kentucky.

Previous forecasts for this system have been rather low confidence, with a mix of solutions producing some measurable snowfall, and solutions producing almost nothing of concern. Overall model agreement is a little better now, suggesting higher confidence that there will indeed be a swath of light snow, but also higher confidence that accumulations will be light -- under an inch even at the higher end, and perhaps with most accumulations limited to grassy or elevated surfaces given a warm starting point for road and surface temperatures. Dry conditions are expected after the wave moves out of the area late this morning.

One other item to watch for is some potential for fog Friday morning. There are some signs that fog may occur -- clearing skies and light winds -- though moisture is a limiting factor. Confidence is too low to include any fog in the forecast for now, but something to consider for later.

KEY MESSAGE 2) Potential for wintry precipitation early next week.

A subtle H5 trough will begin to develop across the eastern half of the US late this weekend into early next week. A wave of low pressure will impact portions of the Ohio Valley late Sunday into Monday as precipitation begins to overspread the region. Thermal profiles early Monday would suggest that some wintry-mix may develop, particularly for portions of southern OH into northern KY. Snow would then be expected for locations north of the mixing zone. Based on latest model guidance, the highest probabilities for accumulating snowfall greater than an inch would be for the counties between the Ohio River and the I-70 corridor. Still plenty of time however for the low pressure track to change, which will influence precip type, precip amounts and timing for this system. Regardless, there remains enough model consensus to continue mentioning the potential for some wintry precipitation that could cause some travel disruptions on Monday.

AVIATION /12Z THURSDAY THROUGH MONDAY/

Generally VFR conditions are expected through the TAF period. The exception will be this morning at KCVG/KLUK, where a TEMPO group for brief IFR conditions has been included in the TAFs, as snow has begun to reduce visibilities. Some MVFR ceilings may also accompany the snow at KCVG/KLUK. For KILN, some very brief MVFR visibilities with snow is possible, although confidence is not overly high that this will occur. KDAY/KCMH/KLCK should remain VFR. The precipitation should move out of the area by 14Z-15Z, leaving VFR conditions for the rest of the TAF period for all TAF sites.

Winds through the period will generally be under 10 knots, with the directions changing several times through the TAF period.

OUTLOOK...MVFR conditions are possible Saturday night. MVFR/IFR conditions are possible Sunday into Monday.

ILN WATCHES/WARNINGS/ADVISORIES

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