textproduct: Wilmington

WHAT HAS CHANGED

No major changes from the previous forecast. Added a discussion regarding the next system arriving mid-week.

KEY MESSAGES

1)Snow potential through the rest of the weekend and early Monday. Below normal temperatures late weekend into early next week.

2)Next chance for rain and snow arrives middle of next week.

DISCUSSION

KEY MESSAGE 1) Weak isentropic lift is pivoting through the Ohio Valley this afternoon, with radar observations and several mping reports showing some snow or rain falling across southern Indiana. Similar to the previous shift, the general expectation is that this precipitation moves through the early later this evening. Dry air and antecedent warmer temperatures will limit the potential of impacts from any snow that does fall.

Later tonight, another trough digging through the Midwest increases broad scale ascent as low pressure forms and deepens off the East Coast. The synoptic lift will help to form a broad area of light snow across southern Michigan, which will move into the local area before daybreak Sunday. Throughout the mid-morning, this band of snow moves southward through the Ohio River. Light accumulations occur throughout this period, and there may be some travel impacts where snow onsets the earliest.

The vort-max pivots through the local area during the afternoon, potentially favoring more enhanced snow showers. Forecast soundings indicate steep low-level lapse rates with saturation into the DGZ. Can not rule out a few period of lower visibility in the heavier snow showers.

Low pressure deepens off the East Coast, enhancing winds through Sunday afternoon and into the evening hours. As snow continues, colder air and winds may help provide worsening road conditions Sunday night into Monday morning. Temperatures in the mid 20s Monday morning support lingering hazardous travel if snow is maintained throughout the overnight period. The local snowfall forecast continues to use WPC QPF with the NBM too low across the southwest half of the area. Snowfall amounts therefore remain similar to previous shifts.

The coldest period of temperatures will be from Monday night into Tuesday morning. Low temperatures are expect to range from the mid teens north to around 20 south. Below normal temperatures continue through the day on Tuesday. A warming trend is develops Wednesday ahead of the next system.

KEY MESSAGE 2) Model guidance continues to bring a strengthening low pressure through the Midwest and Ohio Valley Wednesday night into Thursday. The current consensus is that the low pressure will track far enough north that the majority of the area will see rain. If enough cold air is present, the northern third of the local area may see a chance for snow. Otherwise, attention may be focused on the period of rainfall in an environment where PWATs are 200-300% above normal.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

MVFR CIGs have receded to the north away from local TAF sites. Some light precipitation is possible this evening, but the potential remains low.

Otherwise, confidence is high that restrictions resume between 10-12Z Sunday morning. Period of snow and snow showers occur throughout the day with CIGs dropping to low-end MVFR. MVFR and IFR VIS occur in snow with IFR mentions currently in PROB30. Additionally, toward the end of the TAF, northwest winds increase to between 10-15 knots with gusts of 20-25 knots.

OUTLOOK...Wind gusts up to 30 knots possible after 18Z Sunday. MVFR to IFR ceilings and visibilities possible Sunday night into Monday with snow. MVFR conditions are also possible Wednesday.

ILN WATCHES/WARNINGS/ADVISORIES

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