The overall jet stream pattern since this past Wednesday has allowed temperatures to max out in the lower 90s along with occasionally muggy weather. After one more day in the 90s on Monday, a strong cold front will pass through the area by evening.
That front, combined with a change in the jet stream, will allow cooler and less humid air to filter into the region for a short period of time: Monday night through about Wednesday morning.
The pattern will undergo a change that will push the blazing heat from the western United States eastward. Highs will surpass 90° on Thursday, and highs will be near or above 100° Friday and Saturday.
While we had some hot days this past week, these temperatures slated for later in the week will be the hottest since last summer.
Signs are that the pattern will modify next week to bring more seasonable conditions back to the area. Normal highs for late June and early July run in the upper 80s to around 90°.