Miami Valley , Whitewater Valley, and the I-71 corridor of Ohio/Indiana:
Hazardous Outlook: A low pressure system will develop just Southwest of the region late tonight, allowing for a warm air inversion to occur. This is where warm air overrides cold air at mid levels in the atmosphere, even though temperatures at the surface will be in the upper 30s thunderstorms will form. These thunderstorms are called elevated thunderstorms, they are called this because their cloud deck forms at the mid levels and not the lower levels like your typical tropical summer time type thunderstorms. These storms will tap into very cold air aloft possibly supporting hail the size of quarters tonight, which is near severe limits. Dewpoints will be at best near 50 and 52 degrees is needed for good development of severe thunderstorms. This means the storms may have a hard time becoming severe. None the less there will be a strong jet in the atmosphere making shear near 40 knots this is sufficient enough to support strong updrafts in the storms which is whats needed for cloud growth and water droplets to be carried to the freezing level, also lapse rates, which is the measure of change in temperature over height off the surface, will be steep meaning the temperature profile will be a strong decrease as you progress upward in the atmosphere. The difference between the warm inversion and the cold upper atmosphere will support a strong upward moving of the air in thunderstorm clouds as well. For a visual please see this articles slide show.
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.
Today 3/15 - Partly sunny to mostly cloudy. Winds SW 5 to 15 mph. High 51.
Tonight 3/15 - Cloudy, rain showers developing after 11pm, with a few thunderstorms possible late. Thunderstorms may become severe with some pea to quarter size hail. Winds W 5 to 15 mph. Low 39. Chance of rain 100%. Rainfall around a quarter of an inch.
Saturday 3/16 - Cloudy, scattered am rain showers, then mostly cloudy. Winds N 5 to 15 mph. High 47 falling into the lower 40s. Chance of rain 60%. Rainfall around a quarter of inch or less.
Sat night 3/16 - Cloudy. Winds N 5 to 10 mph. Low 30.
Sunday 3/17 - Cloudy, a chance of rain/snow showers especially by afternoon. Winds NE 5 to 10 mph. High 40. Chance of rain/snow 30%.
Sun night 3/17 - Cloudy, scattered rain/snow showers changing to rain showers. Low 34 early then rising toward sunrise. Chance of rain/snow 70%.
Monday 3/18 - Mostly cloudy, scattered showers and isolated thunderstorms. High 56. Chance of rain 60%.
Mon night 3/18 - Cloudy. Becoming Breezy. Low 31.
Tuesday 3/19 - Partly sunny. Breezy. High 39.
Tues night 3/19 - Partly cloudy. Low 26.
Wednesday 3/20 - Mostly cloudy. High 46.
Wed night 3/20 - Mostly cloudy, a chance of rain/snow showers. Low 30. Chance of rain/snow 30%.
Thursday 3/21 - Partly sunny, a chance of scattered am rain/snow showers. High 47. Chance of rain/snow 30%.
Thurs night 3/21 - Cloudy, scattered rain/snow showers. Low 33. Chance of rain/snow 50%.