As we head into July, the “primary” severe weather season starts to diminish. The reason is that a key driver of atmospheric energy and severe storms, the jet stream, tends to weaken and shift northward.
The focus for severe weather also tends to shift further north along with the jet stream, across the Northern Plains and Upper Midwest.
Take a look at the climatology of severe weather through early August. Note the diminishing probabilities.
The current jet stream has shifted north, across the Northern Plains, Upper Midwest, and Great Lakes (below).
Strong clusters of severe storms can form due to summer’s high heat and humidity, usually during the afternoon and continuing into the evening. These clusters of storms, steered by the jet stream, often travel across large distances, with a northwest to southeast component.
The following two images show the locations of tornado (red) and severe thunderstorm (blue) watches in 2019. These provide a good estimate of the active areas for severe weather this season.
The Southern Plains: Kansas, Oklahoma, and Texas, in particular, seem to be the hardest hit this season.