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Storm activity on Tuesday, July 25, will start from west to east in the early afternoon and continue through the evening, according to the National Weather Service.
"Due to the copious amounts of moisture in the atmosphere and weak steering winds, any shower or thunderstorm has the potential to produce localized flooding downpours into Tuesday," according to AccuWeather Senior Meteorologist Dan Pydnowski.
A look at areas at risk for storms (in green) and for storms as well as flash flooding (in dark green) are shown in the first image above from AccuWeather.com.
Then the big change arrives as dangerous extreme heat from the Midwest will start to spread East, with the potential for a heat wave, defined as three straight days in which the high temperature hits 90 degrees or higher.
High temperatures on Wednesday, July 26 will climb to around 90 degrees or slightly higher with sunny skies.
Thursday, July 27 will be mostly sunny with a high temperature in the low 90s.
Friday, July 28 could be the warmest day of the week -- and the year -- as the high temperature climbs into the mid-90s — or even higher — with partly sunny skies. Possible storms in the afternoon and evening could cool things off a bit.
Temps may approach 100 on Friday, the National Weather Service said in a Hazardous Weather Outlook statement issued Tuesday morning.
"There is a chance that the heat index (the combination of the temperature and humidity) may reach 105 on Friday," the statement said.
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