July weather pattern update
La Niña continues to plug along across the equatorial Pacific and is now likely to hold on into the fall and winter based on the latest guidance. This will certainly be factored once again into our fall and winter seasonal outlooks.
Intense heat continues to broil the south-central and southeast United States while serious, long-term drought conditions continue to plague the Southwest. I just read today that Lake Mead in Arizona and Nevada has dropped to its lowest level since it was filled almost 100 years ago. The annual summer monsoon has begun across the Southwest, but so far, most of the thunderstorm activity has been confined to New Mexico and extreme eastern Arizona.
Farther north in Canada, it looks like a fairly strong west to east flow of air will be dominant during July, which will reduce the risk of long-lasting heat waves and dry spells, as systems will move through every few days with opportunities for some rainfall or cooler, less humid conditions.