Sunday the USA Pro Cycling Challenge wraps up in Colorado with Stage 7 taking cyclists from Boulder to Denver along a 78 mile (126 kilometer) course. The weather appears as though it will mostly cooperate for the final day of this seven day event.
Storms will be a bit more numerous today across the northern Front Range and eastern plains however. Storms should develop along the higher terrain to the west by early afternoon, before pushing across the plains by mid to late afternoon. Coverage and intensity will not be as great as what we say Friday, but a few storms could become strong -- with strong wind being the greatest threat.
Most HiRes models have the greatest chance for storms along and north of I-70 across eastern Colorado which seems plausible. Precipitable water values and CAPE will be greatest across northeast Colorado, with drier and more stable air south of I-70. Storm chances in Denver, as one might expect, will very hit and miss. Best chances could develop just outside the city as they did yesterday, but certainly cannot rule out a cell pushing through this afternoon. HRRR produces rainfall totals from a few tenths to nearly an inch across north central and northeast Colorado through tonight.
Drier Sunday for Pro Challenge
Storm chances decrease across the plains Sunday, but there will still be a chance for a few isolated storms to develop with a good amount of moisture still around. Best storm chances for Sunday should stay west of Denver and Boulder, providing a beautiful late August day for the race.
As for temperatures… We’re expecting most locations across the Denver area and northeast Colorado to the 70s Sunday. MOS guidance for highs range from 80 to 85, but these temperatures have been overdone in recent days. I like the NAM idea for 18z Sunday, with mostly 70s along the I-25 urban corridor, and warmer temperatures across southeast Colorado.
Cold shot for the west
We’ll continue to see chances for storms off and on over the next week, as well as below normal to well below normal temperatures across much of the west. A strong upper level trough will bring unseasonably cool temperatures well into next week for the west, and much of Colorado. You can see that strong trough digging in at the upper levels here:
With that, temperatures will be much cooler than normal, bringing a taste of fall for many from Utah and Colorado north to Montana and the Dakotas. Here is the CFSv2 temperature anomalies for the next five days across the United States.
All that cold air this time of year means... snow! Take a look at what the ECMWF is showing over the next week. Tonight we may see a few locations above 11,000 feet pick up some snow in Colorado, then again this week as things remain unsettled. Take a look at northwest Wyoming through Friday… with a few spots of blue showing in Colorado.