Dangerous Heat ends this evening with scattered severe storms

Update 8:16 p.m. A Destructive Severe Thunderstorm Warning has been issued for Marshall, Tama, Jasper and Poweshiek Counties. The National Weather Service has issued a Severe Thunderstorm Watch, which is in effect through 12 a.m. on July 29.The following counties are included in the alert:Adair County, IA, Adams County, IA, Allamakee County, IA, Audubon County, IA, Benton County, IA, Black Hawk County, IA, Boone County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clayton County, IA, Crawford County, IA, Dallas County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Fremont County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Harrison County, IA, Howard County, IA, Humboldt County, IA, Iowa County, IA, Jasper County, IA, Johnson County, IA, Jones County, IA, Linn County, IA, Madison County, IA, Marshall County, IA, Mills County, IA, Mitchell County, IA, Monona County, IA, Montgomery County, IA, Page County, IA, Polk County, IA, Pottawattamie County, IA, Poweshiek County, IA, Sac County, IA, Shelby County, IA, Story County, IA, Tama County, IA, Union County, IA, Warren County, IA, Webster County, IA, Winneshiek County, IA, Worth County, IA, Wright County, IA.Interactive Radar | Weather Alerts Forecast Discussion:An Excessive Heat Warning and a Heat Advisory remains in effect for much of Central Iowa until 9PM Friday. Just before 4pm Friday, air temperatures for many sites across the state were in the mid to upper 90s with heat indices ranging from 105 to 120 degrees thanks to very high dew points across the state. This immense amount of low-level heat and moisture has led to strong and extreme amounts of potential energy available for thunderstorms to develop as an upper-level disturbance and cold front move south toward Central Iowa. As of mid-afternoon, cumulus clouds have begun to develop along the front from just north of Omaha to Fort Dodge to Mason City. Thunderstorm development is likely around or just after 4pm, along and north of the HWY 20 corridors.Storms will likely grow upscale into complexes and track east and southeast through the evening into the overnight hours, with the best chance of seeing storms at least through midnight north of I-80. Some of high-resolution modeling still suggests the potential for a second complex of storms to develop during the predawn hours of Saturday and move across Southern Iowa.This complex of storms may too contain a risk for damaging winds and hail. Thunderstorm chances will dwindle by Saturday afternoon with slightly cooler air moving into the state. Cooler air will continue to spread in from the north through at least next Monday as a front likely stalls over southwestern Iowa.Any thunderstorm chances through Monday will primarily be confined to southwest Iowa, while cooler, drier air is in place over Central and Northeast portions of the state. Our next best chance for storms may not arrive until next Wednesday and Thursday.Iowa Weather Forecast:Friday Night: Scattered showers and storms. A few storms may be severe. Low around 74F. Winds S shifting to ENE at 5-15 mph.Saturday: Chance of a morning thunderstorm then partly to mostly cloudy. High near 88F. Winds NNE around 10-15 mph.Saturday Night: A few clouds. Low 67F. Winds NE at 10 to 15 mph.Sunday: Partly cloudy. Chance of a storm mainly in Southwest Iowa. High 84F. Winds SE at 10 to 15 mph.Sunday Night: Partly to mostly cloudy. Slight chance of a storm in southwest Iowa. Low 66F. Winds E at 5 to 10 mph.

DES MOINES, Iowa —

Update 8:16 p.m. A Destructive Severe Thunderstorm Warning has been issued for Marshall, Tama, Jasper and Poweshiek Counties.

The National Weather Service has issued a Severe Thunderstorm Watch, which is in effect through 12 a.m. on July 29.

The following counties are included in the alert:

Adair County, IA, Adams County, IA, Allamakee County, IA, Audubon County, IA, Benton County, IA, Black Hawk County, IA, Boone County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clayton County, IA, Crawford County, IA, Dallas County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Fremont County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Harrison County, IA, Howard County, IA, Humboldt County, IA, Iowa County, IA, Jasper County, IA, Johnson County, IA, Jones County, IA, Linn County, IA, Madison County, IA, Marshall County, IA, Mills County, IA, Mitchell County, IA, Monona County, IA, Montgomery County, IA, Page County, IA, Polk County, IA, Pottawattamie County, IA, Poweshiek County, IA, Sac County, IA, Shelby County, IA, Story County, IA, Tama County, IA, Union County, IA, Warren County, IA, Webster County, IA, Winneshiek County, IA, Worth County, IA, Wright County, IA.

Interactive Radar | Weather Alerts

Forecast Discussion:

An Excessive Heat Warning and a Heat Advisory remains in effect for much of Central Iowa until 9PM Friday. Just before 4pm Friday, air temperatures for many sites across the state were in the mid to upper 90s with heat indices ranging from 105 to 120 degrees thanks to very high dew points across the state.

This immense amount of low-level heat and moisture has led to strong and extreme amounts of potential energy available for thunderstorms to develop as an upper-level disturbance and cold front move south toward Central Iowa. As of mid-afternoon, cumulus clouds have begun to develop along the front from just north of Omaha to Fort Dodge to Mason City. Thunderstorm development is likely around or just after 4pm, along and north of the HWY 20 corridors.

Storms will likely grow upscale into complexes and track east and southeast through the evening into the overnight hours, with the best chance of seeing storms at least through midnight north of I-80. Some of high-resolution modeling still suggests the potential for a second complex of storms to develop during the predawn hours of Saturday and move across Southern Iowa.

This complex of storms may too contain a risk for damaging winds and hail. Thunderstorm chances will dwindle by Saturday afternoon with slightly cooler air moving into the state. Cooler air will continue to spread in from the north through at least next Monday as a front likely stalls over southwestern Iowa.

Any thunderstorm chances through Monday will primarily be confined to southwest Iowa, while cooler, drier air is in place over Central and Northeast portions of the state. Our next best chance for storms may not arrive until next Wednesday and Thursday.

Iowa Weather Forecast:

Friday Night: Scattered showers and storms. A few storms may be severe. Low around 74F. Winds S shifting to ENE at 5-15 mph.

Saturday: Chance of a morning thunderstorm then partly to mostly cloudy. High near 88F. Winds NNE around 10-15 mph.

Saturday Night: A few clouds. Low 67F. Winds NE at 10 to 15 mph.

Sunday: Partly cloudy. Chance of a storm mainly in Southwest Iowa. High 84F. Winds SE at 10 to 15 mph.

Sunday Night: Partly to mostly cloudy. Slight chance of a storm in southwest Iowa. Low 66F. Winds E at 5 to 10 mph.