Iowa Weather Forecast: Severe Storms, Flash Flooding Risk Today and Friday
The Iowa weather forecast is becoming increasingly active as multiple rounds of thunderstorms are expected across the state through Friday night. In addition to the risk of severe weather, a flood watch has been issued for portions of Iowa due to the potential for heavy rainfall and flash flooding.
There are two separate periods of concern. The first arrives later today and tonight, followed by another round of potentially severe storms on Friday afternoon and evening.
If you have outdoor plans, travel scheduled, or live in a flood-prone area, now is a good time to review your severe weather safety plan and stay updated on the latest forecast.
Severe Weather Risk Today (Thursday)
Scattered thunderstorms are expected to develop across Iowa later this afternoon and continue through tonight. The greatest coverage of storms is expected across central, western, and southern Iowa.
According to the Storm Prediction Center, the atmosphere will become increasingly unstable this afternoon with enough energy available to support strong to severe thunderstorms. Some storms may organize into multicell clusters or isolated supercells capable of producing severe weather.
The primary threats today include:
- Large hail
- Damaging wind gusts
- Localized flash flooding
- An isolated tornado, especially across southwestern Iowa
While widespread severe weather is not expected, any storm that becomes stronger could quickly produce dangerous conditions. The tornado threat remains relatively low but cannot be ruled out this evening as wind patterns in the lower atmosphere become more favorable for rotating storms.
Cloud cover may limit storm intensity in some areas, but the Storm Prediction Center continue to monitor trends closely.
Flash Flood Watch in Effect Tonight
The greatest concern for many Iowans may actually be heavy rainfall rather than severe weather.
A very moist air mass moving into the state will create favorable conditions for efficient rainfall production. Thunderstorms may repeatedly move over the same locations, leading to excessive rainfall totals in a short period of time.
The highest flash flood risk appears to be across portions of central and southern Iowa, particularly south of Highway 30 and west of Interstate 35.
Rainfall totals of 2 to 4 inches are possible by Friday morning, with isolated locations potentially receiving more than 5 inches where thunderstorms repeatedly track over the same area.
Urban areas, low-lying locations, and places that have received recent rainfall will be most vulnerable to flash flooding. Drivers should never attempt to cross flooded roadways, as water depth and road conditions can be difficult to judge after dark.
Iowa Weather Forecast for Friday
After storms gradually move east Friday morning, many areas may experience a temporary break in rainfall during the afternoon. However, the atmosphere is expected to recharge quickly.
Temperatures will climb into the 80s while humidity levels continue to increase. This combination will create a highly unstable environment capable of supporting another round of severe thunderstorms later Friday afternoon and Friday night.
The Storm Prediction Center has placed much of Iowa under a Slight Risk (Level 2 of 5) for severe weather.
Friday’s Severe Weather Threats
Friday currently appears to have the higher severe weather potential compared to Thursday.
Strong instability is expected across much of Iowa, which could fuel storms capable of producing:
- Large to very large hail
- Damaging wind gusts
- Heavy rainfall
- A few tornadoes
Some of the strongest storms may initially develop in Nebraska before moving east into Iowa during the evening and overnight hours. Additional storms may also develop directly over Iowa along a frontal boundary.
The exact location of the highest threat will depend on where storms develop and how much sunshine Iowa receives during the afternoon. If confidence increases in more widespread storm development, portions of Iowa could be upgraded to an Enhanced Risk in future Storm Prediction Center outlooks.
Flooding Concerns Continue Friday Night
Flooding concerns may continue into Friday night, especially in areas that receive heavy rainfall tonight.
Additional rainfall totals of 1 to 3 inches will be possible with Friday night’s storms. If the heaviest rain falls over areas already saturated from previous storms, flash flooding could become a more significant concern.
While widespread river flooding is not currently expected, rapid rises on creeks, streams, and smaller rivers may occur where repeated rounds of heavy rain develop.
Looking Ahead
The active Iowa weather pattern will continue into the weekend and early next week.
Saturday is expected to bring a temporary break from widespread storms, although isolated thunderstorms cannot be ruled out. Additional chances for showers and thunderstorms return Sunday into Monday as more disturbances move across the Midwest.
Temperatures will remain above normal with highs generally in the 80s and increasing humidity levels.
Stay tuned to IowaWeather.com and the ISCN Weather app for the latest forecast updates, radar trends, watches, warnings, and severe weather alerts across Iowa.