Thunderstorms and downpours will cause additional flooding in the Mississippi Valley on Wednesday, while residual flooding is still occurring across the Southern Plains due to runoff from heavy rain over the last few days.

Scattered storms will move into the Eastern third of the country tomorrow. 

The national forecast for Wednesday, June 2. (Fox News)

The national forecast for Wednesday, June 2. (Fox News)

Excessive heat warnings and heat advisories are in effect from portions of the Southwest through interior California and the Northwest as afternoon highs in the 90s and 100s continue for a couple more days.    

June 1 was the first day of the Atlantic Basin hurricane season, which runs through Nov. 30.  

Expected high temperatures tomorrow. (Fox News)

Expected high temperatures tomorrow. (Fox News)

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While the Atlantic is currently quiet, we are expecting above-average activity this year, especially during the August-October peak of the season.   

And for the seventh year in a row, we’ve already seen the first named storm occur before June 1, in May.