The high temperatures today were expected to lead to some scattered strong thunderstorms through the afternoon and evening.
The National Weather Service issued severe thunderstorm warnings and tornado warnings in parts of Maryland Tuesday evening.
The storms, which move from west-north-west to southeast, could be severe with high winds, heavy rain and frequent lightning.
The threat of severe storms could continue into Wednesday, with the best chance of storms from 1-6 p.m.
Temperatures will remain high the rest of the week, and there could be record-breaking heat both Friday and Saturday, Johnson said. The heat index Wednesday could be between 105 and 110.
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