textproduct: Wilmington

WHAT HAS CHANGED

Increased precipitation chances and snow for today and adjusted hourly temperatures colder this afternoon.

KEY MESSAGES

1) Widespread light Snow will continue early this morning for areas along and east of Interstate 71. Snow, along with cooling pavement temperatures, may result in slippery spots on roads.

2) Snow showers continue throughout the day on Saturday. Some snow showers will result in sudden drops in visibility, along with a quick coating of snow.

3) Bitterly cold temperatures are forecast Saturday night through Wednesday morning with the coldest temperatures occurring Monday through Tuesday morning.

DISCUSSION

KEY MESSAGE 1...

Elongated mid and upper level low observed from the Upper MS Valley thru the Great Lakes. Shortwave disturbance was resulting in widespread snow across areas along and east of I-71. Pavement and boundary layer temperatures are marginal - so therefore limiting impacts on area roads. Have generally increased pops over NBM solution and allowed this widespread pcpn to exit the east between 10-12z. Additional accumulation prior to ending looks to be around an inch. The winter weather advisory has remain unchanged and will expire at 12Z.

KEY MESSAGE 2...

Western portion of the mid/upper level low digs southeast thru the Mid MS Valley today and into the Lower Ohio Valley tonight. A strong secondary cold front will sweep east across the area by early afternoon. Colder air moving in aloft steepens lapse rates, supporting the potential for snow showers from the late morning and into the afternoon across the area. Widespread accumulations are not expected with this activity but locally, reduced visibility and quick coatings of snow may result in challenging travel conditions. Have general accumulations of an inch or less. Have increased pops and snowfall over NBM solution. Model signal suggests a better threat for snow squalls east of our area this afternoon. Will monitor radar/model trends for impacts in ILN/s eastern counties this afternoon.

KEY MESSAGE 3...

A prolonged period of bitterly cold temperatures and wind chills will be in place from Saturday night through Tuesday night, as a deep longwave and subsequent shortwaves bring reinforcing shots of cold air to the region.

A back door cold front moves through the region tonight, bringing the initial surge of arctic air into the region. Tonight's low temperatures quickly fall to the teens and even single digits in spots. With light westerly flow in place, feels like temperatures fall to near zero and even slightly below for areas north of I-70.

Quick education break here: as a reminder, feels like temperatures (also known as wind chill this time of year) take into account the effects of wind AND temperatures on the body. This measurement affects both people and animals/livestock. When wind is factored in, people and animals lose heat faster, which can increase frostbite and hypothermia risks, as well as added stress on the body. To learn about the warning signs of hypothermia and frostbite as well as how to protect your livestock and pets, visit www.weather.gov/safety/cold.

OK, back to the forecast. Temperatures do follow a subtle diurnal trend on Sunday, but highs only reach the 20s. When we factor in some breezy southwest winds, gusting to around 25 MPH at times, those daytime feels like temperatures remain in the single digits all day long. A reinforcing shot of cold air arrives Sunday night into Monday as another short wave swings through the Great Lakes region. Overnight lows fall once again to the teens with feels like falling to single digits.

With the tightened pressure gradient present from the shortwave, winds will gust between 20-30 MPH during the day on Monday, with high temperatures in the teens. This will result in feels like temperatures between -5 and -10 along and north of I-70 and around 0- 5 degrees for areas south, during the day on Monday. Cold Weather Headlines will likely end up being needed. Monday night into Tuesday morning will be the coldest night of the period, with lows around zero and feels like temperatures between -10 and -15 for areas along the north of I-70, with 0 to -5 degrees for areas south.

Temperatures rebound slightly on Tuesday, rising into the teens/20s during the day and falling to the single digits overnight. By Wednesday, the trough flattens out a bit and we begin warm air advecting ahead of another shortwave system.

Now is the time to plan for an extended period of extreme cold by inspecting your residence, vehicle, and have plans in place for outdoor livestock. For information on how to prepare yourself, your home, and your car for extreme cold, visit www.weather.gov/safety/cold-before.

AVIATION /06Z SATURDAY THROUGH WEDNESDAY/

System moving thru ILN/s eastern counties will bring snow with IFR conditions early this morning. Widespread coverage of snow shifts east and diminishes between 10-12Z. Expect lingering IFR ceilings for a period this morning, which lift to MVFR early and eventually VFR this afternoon. Additional snow showers will develop across the area late morning thru afternoon. Brief periods of IFR or LIFR will be possible in any snow shower today. Due to limited coverage have kept forecast during snow showers in MVFR category.

Westerly wind gust to 20-25 kts today and then diminish to 10 kts or less tonight.

OUTLOOK...Winds may gust up to 30 kts Monday.

ILN WATCHES/WARNINGS/ADVISORIES

OH...Winter Weather Advisory until 7 AM EST this morning for OHZ064-065- 073-074-079>082-088. KY...Winter Weather Advisory until 7 AM EST this morning for KYZ094>100. IN...None.