DES MOINES, Iowa – More nights of overnight thunderstorms will lead to the potential for flash flooding across Central Iowa. Channel 13 Meteorologists are watching as a slow moving front will sit stationary over Central Iowa tonight through Friday. This will lead to more rounds of thunderstorms, mainly during the overnight hours.
According to Meteorologist Megan Salois, moisture from the Gulf of Mexico, as well as from the monsoon season on going in the southwest US, will be pulled north around an area of high pressure south of Iowa. As this moisture moves north, it will hit that front and the moisture will be squeezed out in the form of heavy rains in the overnight hours. At the same time, a disturbance along the jet stream will cross Central Iowa in the upper layers of the atmosphere fueling more storm development.
The best time frame for storms in Central Iowa is after midnight and before 8 a.m.. Tuesday afternoon, we will dry out for a short period of time under partly sunny skies. It will not be as hot, but still humid. The stationary front will still be in place with humidity building south of the front, resulting in more storms forming again late Tuesday and early Wednesday morning.
Rainfall amounts could be hefty in some localized spots. In general, 3 night totals will range from 2 to 6”. The highest amounts will fall just north and parallel to I-80.
The main severe weather risk is flash flooding with these storms as heavy rain will occur on already saturated ground. Plus the rain will fall at night when visibility is limited and drivers may not see flooded roads. A few storms may produce gusty winds and small hail. There will be frequent lightning.