Under our current North American Monsoon weather pattern, low pressure anchored to the west off the California coast and the high pressure settled into the central southern plains to the east, storms will be working through the area through this weekend. Less hot temperatures will be the immediate impact, but hazards with this current set up will include brief heavy downpours with slow moving storms, lowered visibility (on roadways if you drive through those downpours, ponding on roadways are possible too), flash flood watches or warnings -especially in slot canyons, arroyos and dry/small tributaries), and the possibility of debris flows.
Grand Junction stats for this time of the year are 93°H/64°L with a rain deficit of -1.83″. Montrose by the numbers, 90°H/58°L – rain deficit -3.42″ for the this time of the year.
The extended forecast does have movement with the western low getting pulled into the main flow and the eastern high expanding back over the Four Corners for late this weekend and the start of next week. This will not entirely shut down the tropical rain influence because plenty will have arrived/will be lingering and under neath the high pressure system the Western Slope should return to the daily mountain storm pattern with valley drift (and hotter temperatures) next week.