Miami Valley , Whitewater Valley, and the I-71 corridor of Ohio/Indiana:
Low pressure will strengthen quickly off to our SW tonight becoming very intense and tightly wound. Initially it will keep mild air around with some heavy rain showers and a few thunderstorms developing late. The low will move off to our SE by dawn bringing very cold air down from Canada this will cause rain to transition to snow by late morning/noon Wednesday with snowfall amounts generally around 1 to 3 inches, some locations South will see less while North of I-70 will see a bit more. This is all still dependent on how fast the change over occurs in your area. Winds will gust to 45 mph with falling temps so any precipitation on the ground will freeze rapidly by Wednesday afternoon and night. Temps by Thursday morning will be in the single digits and wind chills near -10 for some.
Mild air returns quickly Friday before another cold shot comes late in the weekend followed by a few days of colder air.
The following is the seven day forecast for the Dayton metro area and a 50 mile radius around it. Other metro areas like Columbus, Cincinnati, and Portsmouth are not included. For those areas please request a separate forecast. Thanks.
Tonight 3/11 - Mostly cloudy, scattered showers and a few thunderstorms after midnight, rain heavy at times by dawn. Winds calm becoming SE 5 to 10 mph. Low 45. Chance of precipitation 100%. Rainfall around a half of an inch or less.
Wednesday 3/12 - Mostly cloudy, rain changing to snow becoming scattered snow showers by pm. Some thunder possible. Breezy. Winds NE becoming N 15 to 25 mph gust to 45 mph possible. High 45 around dawn falling through the 20s by pm. Chance of precipitation 100%. Rainfall around a quarter of an inch possible. 1 to 3 inches of snow possible. North of I-70, 2 to 5 inches possible.
Wed night 3/12 - Mostly cloudy, a few scattered snow showers early, then clearing by dawn. Breezy early. Winds NW 15 to 25 mph, gust to 35 mph, decreasing to 5 to 10 mph late. Low 7. Wind chills as low as -10. Snowfall a coating or less.
Thursday 3/13 - Mostly sunny. Winds W 5 to 10 mph. High 29. Wind chills as low as -5 early.
Thur night 3/13 - Partly cloudy. Winds SW 5 to 15 mph. Low 24 early then rising late.
Friday 3/14 - Mostly sunny, becoming partly sunny. Breezy. Winds SW 10 to 20 mph. High 55.
Fri night 3/14 - Mostly cloudy, scattered rain showers. Low 35. Chance of rain 50%.
Saturday 3/15 - Mostly cloudy, a chance of a few scattered rain showers early. High 49. Chance of rain 30%.
Sat night 3/15 - Mostly cloudy. Low 33.
Sunday 3/16 - Mostly cloudy. High 39.
Sun night 3/16 - Partly cloudy. Low 21.
Monday 3/17 - Partly sunny. High 37.
Mon night 3/17 - Mostly clear. Low 28.
Tuesday 3/18 - Partly sunny. High 47.
Tues night 3/18 - Partly cloudy. Low 31.