textproduct: Wilmington

SYNOPSIS

Snow will develop this evening and increase in intensity overnight before ending Tuesday morning, as an upper level shortwave trough moves through the Ohio Valley. High pressure offers dry weather later Tuesday into Wednesday. A cold front which will be accompanied by snow showers will drop south through the Great Lakes Wednesday night into Thursday providing a reinforcing shot of cold air. The active weather pattern continues with additional chances for wintry precipitation late in the week into next weekend.

NEAR TERM /THROUGH TUESDAY/

Surface high pressure and broad mid level ridging works across the area this afternoon. Progressive mid level shortwave TROF to track east from the Plains into the MS Valley this evening and across the Ohio Valley Tuesday. Ahead of this system widespread snow to move in from the west tonight between 8pm and midnight. The best lift and snowfall rate look to occur between 2 AM and 6 AM. The large area of snow quickly moves through overnight ending between by 10 AM Tuesday morning as the trough axis moves off to the east. Snowfall totals are expected to place in the 2 to 4 inch range for most locations. Areas closer the Ohio River may end up seeing a period of freezing or sleet as some warmer air mixes in for a period overnight. Snowfall in this area looks to fall in the 1 to 3 inch range with up to a tenth of an inch of ice possible. Additionally, more favorable (higher) snow to liquid ratios between 12 and 14 to 1 and the possibility of mesoscale bands may lead to some locations observing snowfall exceeding 4 inches. Have an area over the far northwest with 3 to 5 inches. There are still uncertainties regarding the amount of mixing with freezing rain/sleet and exactly where mesoscale bands setup. This will affect the placement of the highest amounts. Travel impacts are expected overnight and during the Tuesday morning commute. A Winter Weather Advisory has been continued for the entire area to highlight travel impacts and forecast snow totals. Low temperatures to range from the mid 20s northwest to the upper 20s southeast. Easterly winds at 5 to 10 mph shift to the northwest late.

SHORT TERM /TUESDAY NIGHT/

Progressive mid level TROF to shift quickly off to the east Tuesday with snow ending from west to east by mid morning. Surface high pressure builds into the area Tuesday night. After the snow moves east Tuesday morning, expect cloudy, cold, and dry conditions with light northwesterly winds. High temperatures to range from near 30 northwest to the upper 30s southeast.

Clouds hold most of the night but may begin to break up from the southwest toward sunrise Wednesday. Cold lows range from the upper teens northwest to the lower 20s southeast.

LONG TERM /WEDNESDAY THROUGH MONDAY/

Seasonably cold air mass remains intact for the extended forecast period. Dry conditions can be expected on Wednesday, but a weak cold front drops down Wednesday night, which may result in some light snow accumulations across our CWA. Currently, primarily expecting only a few tenths of an inch from this weaker system. However, higher SLRs could push accumulations to 0.5" to 1.0" in some of our northern counties. CAMs will offer some better insight on snowfall totals.

Precip chances remain low for Thursday and Friday, but another system looks to develop for this weekend. Best signal for precip this weekend is now focused late Saturday into Sunday, with thermal profiles favoring snow as the primary p-type. However, a wintry-mix is still possible, especially for counties south of the Ohio River.

AVIATION /23Z MONDAY THROUGH SATURDAY/

All sites are VFR at the beginning of the period but conditions will quickly deteriorate from west to east as snow overspreads the region this evening.

Anticipating an abrupt drop in both CIGs and VSBYs with snow onset, dropping initially to MVFR then IFR, with LIFR conditions possible (particularly along the I-70 corridor (KDAY KCMH KLCK)) by late night/early morning hours. For now, have kept LIFR conditions as a TEMPO, but these might need to end up as prevailing depending on how guidance trends.

Snow tapers off Tuesday morning around 12Z, leaving IFR/LIFR CIGs behind with MVFR VSBYs. Conditions will slowly improve as we head into the afternoon hours, though appears that at least a MVFR deck will hang out through the evening.

Winds are light with an easterly component this evening, becoming variable overnight before shifting to out of the northwest by Tuesday morning, increasing to around 5-10 knots.

OUTLOOK...MVFR CIGs will prevail into Tuesday. MVFR CIGs will also be possible Wednesday night into early Thursday.

ILN WATCHES/WARNINGS/ADVISORIES

OH...Winter Weather Advisory until 10 AM EST Tuesday for OHZ026-034-035- 042>046-051>056-060>065-070>074-077>082-088. KY...Winter Weather Advisory until 10 AM EST Tuesday for KYZ089>100. IN...Winter Weather Advisory until 10 AM EST Tuesday for INZ050-058-059- 066-073>075-080.