Upper ridge currently parked over UT will begin to slowly move eastward this weekend. This will bring more unseasonably warm days to CO this weekend, but as the upper ridge moves to our east, we will see some additional moisture from southwest flow aloft. Precip chances will increase west of the Divide from Friday through Monday, although only slight chances we will see any precip in the foothills. Best chance for showers looks to be from late Sunday into Tuesday for the foothills.
Unfortunately the increased southwest flow aloft will bring gusty south to southwest surface winds, which will increase fire dange from this wekeend into the middle of next week, especially in the lower foothills where grasses have already turned brown.
The upper ridge is forecast to move to the Ohio Valley by late next week which will allow a vigerous Pacific upper trough and cold front to move from the west coast into the Rockies by late next week. This will be the first storm of the season that will hoist winter type advisories across the west coast and into the inter-mountain region. Models are in good agreement and have been consistent with this system, so confidence is fairly high in the forecast at this time. For CO, the system will bring precip into western CO beginning next Thursday with snow levels between 7000-8000 ft. Precip chances look best for the foothills from late Thursday night into early Saturday morning, with Friday being the most likely timeframe. Snow levels look like 7000-8000 ft during the day on Friday, lowering to near Plains level Friday night. Snow amounts look like they will remain on the light side with a few inches in most areas above 7000-8000 ft. Majority of precip will remain on the west side of the Divide, and north of I-70 as the system passes as an open trough, so no big upslope component is forecast at this time. Before the system arrives, southwest winds could get quite strong on Thursday and Thursday night. Obviously this is still a long ways off, so the forecast could change significantly next week, so stay tuned for further updates.
So still time to enjoy our warm early Fall weather before before things change. After the system next week, long range models call for more seasonal type weather for early October.
_________________
"Climatology is what you expect, Weather is what you get".
"It is better to be roughly right than precisely wrong".
Too bad future generations aren't here to see all the great things we are spending their $$ on!!
