Monsoon will weaken
We expect the upper ridge that has been over the plains during much of July to slide more over the Western U.S. during the first half of August.
This ridge shift will weaken the monsoon which produced locally heavy thunderstorms and resulted in some flash-flooding, mainly over the mountainous terrain in July.
July will end up two to four degrees warmer than normal with the greatest departures in the Northwest.
Going through August 2017, despite a weakening monsoon, higher-elevation thunderstorms in the Rockies can lead to slightly higher-than-average rainfall while areas east of the mountains, including Denver, Colorado Springs and Pueblo, will likely have a drier-than-normal August.
As you would expect, the drier eastern portions of Colorado to the east of the Front Range will have higher-than-normal temperatures in August, while the more active mountainous terrain will have near or even slightly below-normal readings.
Daily temperatures in Denver will slip from a high of 90 degrees and a low of 60 degrees on Tuesday to a high of 84 degrees and a low of 54 degrees on Aug. 31. For the month, temperatures are expected to be up about 2 degrees higher than normal.