Pattern Shift Brings Potential Record Heat to the West, Cool and Wet Conditions in the East

All About 'Heart Attack' Snow

A shift in the weather pattern is ongoing for much of the country as June begins.

This shift is bringing temperature changes for many, as well as an increase of showers and thunderstorms across portions of the South and East.

(MORE DETAILS: Dangerous Western Heat Ahead)

An upper-level trough, or southward dip in the jet stream, that has been in place over the West is slowly sliding eastward and being replaced by an upper-level ridge of high pressure, pushing the jet stream well into western Canada.

Hot temperatures will continue to build across the West as the week progresses, just as meteorological summer begins (June 1 - August 31). 

Meanwhile, cooler conditions are begun to be experienced across parts of the East, although for most locations highs will be close to average for this time of year.

In fact, this temperature setup is very similar to what is expected for this June. The June forecast by The Weather Company, an IBM Business, calls for above-average temperatures in the West, colder-than-average conditions for portions of the central U.S. and near to slightly above-average temperatures in the East.

(MORE: Summer Temperature Forecast)

In addition to the temperature changes, there will be an increase of showers and thunderstorms, especially for the Southern Plains where more rain is not needed after the flooding that took place in Texas last week.

(MORE: Heavy Rain Returns to Southern Plains)

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