Undelatus Asperatus clouds were spotted in the Miami Valley. According to NOAA the name translates to roughened waves. The clouds were recently added to the International Cloud Atlas by the World Meteorological Organization in 2017.
These clouds indicate turbulence in the atmosphere with risking and sinking air. They tend to be rain less clouds, but can be seen before or after a thunderstorm.
This photo was taken by Jacob Hawvermale in Germantown.
This photo was taken by Kettering Police Officer Rustad near the old fire department headquarters on Dorthy Lane.
6:35 p.m. Update: A line of storms continues to track across the Miami Valley. The stronger thunderstorms will be from Cincinnati up into Warren and Clinton County. This area did not see as much rain earlier today and may still have enough energy to produce a severe thunderstorm.
The greatest risk will be tree damage, power outages, and minor flooding.
The mainline of storms is stretched from Urbana to Cincinnati and tracking east about 30 mph. The heavy rainfall will be east of the Miami Valley by 8 p.m. Some stratiform rain has developed behind the main line of storms. This is steady light to moderate rainfall that will continue for a few hours especially north of I-70.
A few showers will remain possible through about 5 a.m. early Tuesday morning. A cold front will move through the region and dry us out a bit. Temperatures will be in the mid-80s for afternoon highs for the rest of the week.
5:06 p.m. Update: Strong thunderstorms track across the Miami Valley. A 46 mph wind gust was reported at the Dayton Cox Airport. A line of storms has developed from North Hampton to Hamilton.
This line is capable of 50 mph wind gusts. Power outages and tree damage will be possible.
A stronger line of thunderstorms has developed from Wapakoneta, Ohio to Greensburg Indiana. This line has produced thunderstorms with wind gust up to 60 mph north of Greensburg.
4:22 p.m. Update: Strong thunderstorms track into the Miami Valley from Indiana. 45 mph wind gust are possible with a thunderstorm moving east into Miami County and northern Montgomery County.
Another strong thunderstorms will move into Mercer County. This storm is moving east at 30 mph with wind gust up to 50 mph. Very heavy rainfall may produce localized flooding along low lying streets.
Scattered strong thunderstorms will continue through 8 p.m.
2:13 p.m. Update: A line of strong thunderstorms moves into northwestern Darke County and Southern Mercer County. 50 mph wind gusts are possible. It is moving east at 25 mph.
2:00 p.m. Update: As we wait the arrival of thunderstorms in the Miami Valley, the heat index in Dayton has reached 100 degrees. The actual temperature at 2 p.m. is 91 degrees.
Original Forecast: Pop up thunderstorms have developed across Montgomery, Greene, Clinton, Warren, and Butler Counties. These storms will produce a period of heavy rainfall and quickly weaken as they track east.
A line of thunderstorms has developed from Toledo, Ohio to Muncie, Indiana. These storms are already much stronger producing more lightning. This line will mostly track east and slightly southeast across Mercer, Auglaize, Shelby, Logan, Darke, Miami, Champaign, and Clark County.
Additionally scattered storms are developing south of this line near Indianapolis that will track east into the region.
You can expect scattered thunderstorms with off and on periods of heavy rainfall through 10 p.m. tonight. Some of these storms may be capable of very strong wind gusts that will cause tree damage and power outages.
Have a plan to take shelter indoors and away from windows. These thunderstorms will also produce a dangerous lightning.
As of 1 p.m. the current temperature in Dayton was 89 degrees. The dew point was 75 degrees making it feel rather miserable outside. The heat index was 99 degrees in Dayton and 100 degrees in Springfield.
The combination of high heat and high moisture content will result in numerous thunderstorms this afternoon and evening. We will lose instability that encourages storm development after the sun goes down around 9:56 p.m. We will lose all instability as a cold front moves through early Tuesday morning. Behind the cold front, we will see clearing skies, calming wind, less moisture, and cooler temperatures. After today, highs will be in the mid-80s.