textproduct: Wilmington

WHAT HAS CHANGED

Steady snow has ended across eastern counties.

KEY MESSAGES

1) Scattered snow showers are expected through this evening, potentially lingering into early tonight. Although roads are expected to be mainly wet during the daytime, some isolated slick spots may develop after sunset with falling air and ground temperatures.

2) Unseasonably cold air, characterized by temperatures in the teens and wind chill values in the single digits above zero, will settle into the area by early Tuesday morning. Dress in layers if you must be outdoors during this period. Some light snow is also possible in parts of the area on Wednesday.

DISCUSSION

KEY MESSAGE 1) Steep/deep LL lapse rates have developed this afternoon with a /very/ strong signal from the snow squall parameter given the anomalously-deep/digging PV anomaly and plenty of moisture in the DGZ. This will allow for widespread snow showers this 4 5 5 5 afternoon area- wide, lingering into this evening. In fact, there are some solutions showing the development of some instby in the DGZ, so suppose an ISO rumble of thunder cannot be completely ruled out through early evening.

In terms of impacts, localized heavier snow showers will be capable of reducing visibilities suddenly and significantly at times, especially as wind will continue to gust to 30-35 MPH at times through early evening. During the daytime period, expect any accumulations to be mainly on grassy and elevated surfaces with roads remaining mainly wet due to antecedent warm ground temps. However, as air temps continue to fall below freezing into the evening hours, some slick spots may begin to develop on area roadways, particularly after sunset. The latest guidance suggest that untreated surface road temps will generally go below freezing from around 02z-04z. If coverage of snow showers remains widespread through this time, certainly some icy/slick spots will likely develop. But there still remains some uncertainty regarding how widespread/persistent the activity will remain later into the evening.

KEY MESSAGE 2) An unseasonably cold air airmass will settle into the region tonight through Wednesday, with overnight lows in the teens and 20s expected. Daytime highs on Tuesday will top out around the freezing mark, which will be about 20 degrees below seasonal norms.

Additionally, gusty winds on the order of 15-25kts will continue through tonight into early Tuesday morning, leading to wind chill values in the single digits above zero. Those venturing outdoors late tonight into early Tuesday morning should dress in layers.

Additionally, a band of light snow will move into parts of the area early Wednesday morning, potentially leading to additional light accumulation, especially near/west of I-75. This may lead to isolated slick spots on untreated surfaces for the Wednesday morning commute.

AVIATION /00Z TUESDAY THROUGH SATURDAY/

Scattered snow showers will continue for the first half of the period. These will bring temporary visibility reductions to IFR, but as the night goes on, intensity and coverage of snow showers will decrease. This will result in the chance of IFR visibilities reducing quite a bit, but not completely ending. However, it is enough to only carry MVFR restrictions after 04Z. Additional snow showers will occur during the day, primarily affecting the Columbus terminals. Ceilings will ve varying between VFR and MVFR until after 12Z when VFR is forecast to prevail. Gusty west winds will decrease slowly through the night. Gusts may pick up a bit on Tuesday but generally be below 25 kt.

OUTLOOK...MVFR ceilings are likely Wednesday into Wednesday night with ceilings possibly falling to IFR with MVFR visibilities.

ILN WATCHES/WARNINGS/ADVISORIES

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