12:30 PM, Friday, September 25, 2015
It is looking increasing likely that the remainder of September will be completely dry with above average temperatures. Pueblo, Denver, and Cheyenne are all on track to have the warmest September on record. Boulder has a few warmer Septembers from the 1940s-1960s, but that has mostly to do with the poorly sited rooftop thermometer those years that introduced a large warm bias in the daily low temperatures. Denver has had only 0.04″ of precipitation, and Boulder is at 0.06″. This is among the driest for both locations, but both locations have had a few Septembers with no measurable precipitation (in Boulder 1922, 1943, and 1944 only saw a trace).
We are not likely to set any daily record highs this weekend, but we will get close. The records highs for Denver on Saturday and Sunday are 90 and 92, and for Boulder the records are 89 and 92.
Don’t forget the total lunar eclipse Sunday evening from 8:11 to 9:23 MDT. The moon is in the part of it’s orbit that is closest to Earth– a supermoon. A supermoon total eclipse last occurred in 1982 and is not due again until 2033.
12:20 PM, Tuesday, September 22, 2015
The autumnal equinox occurs at 2:21 AM Mountain Daylight Time on September 23rd. Front Range weather is likely to cool down to about average for this time of year (low to mid 70s for Denver and Boulder). There will likely be a few clouds around Wednesday and a very small chance for an afternoon shower, but most areas should remain dry.
Dry and warmer-than-average weather is likely to be back by the weekend. I know we could use some moisture, but the good news for sky watchers is that it may be clear for Sunday evening’s total lunar eclipse. The partial eclipse phase will begin before the moon rises, but the peak period will occur from 8:11 to 9:23 mountain time. The moon won’t be very high in the sky at that early hour, so make sure you seek out a place with a good view to the east. The moon is also at its closest approach to Earth (called a supermoon) which makes it about 7% larger than when it is at its farthest distance. So it will be an unusual supermoon eclipse.
1:10 PM, Friday, September 11, 2015
After a cooler Friday, temperatures will warm up again and likely be above average by Sunday throughout the Colorado-Wyoming region. There is very little chance for showers. Some weak cool fronts next week (after Monday) probably won’t change the temperature dramatically or bring widespread rain. There could be a few windy periods associated with those fronts that may elevate local fire danger. It’s sure a different pattern than the one that brought Boulder 9.08 inches of rain in 24 hours two years ago on September 11-12. Have a nice weekend!
1:15 PM, Thursday, September 3, 2015
The 3-day weekend is likely to become progressively drier by Monday with near average temperatures (afternoon highs around 80 in the Front Range urban corridor).
There is a flow of moisture from the tropical Pacific currently over Colorado and Wyoming that will likely last into the early part of the weekend. That will enhance the chance for scattered afternoon and evening showers and thunderstorms. But the lower levels of the atmosphere are rather dry which should limit the extent and duration of heavy rain. Some areas may get very little.
By Sunday the atmosphere is likely to become a bit drier, so the latter part of the holiday weekend is looking good for outdoor activity. Be careful with fire. The fire danger isn’t high, but many areas have been drier than average for over a month (especially north of I-70).