As of May 26, this month has been 4 degrees below average in Pueblo and 3.4 degrees below average in Colorado Springs. But, current long-range forecasts indicate this pattern will change from June through August.
Summer 2021 Temperature Outlook
The Climate Prediction Center's 3-month outlook indicates a 50-60% probability of above-average temperatures in Colorado. This is based on decadal trends and computer modeling.
Normal Summer Climatology
A normal summer in Colorado Springs:
A normal summer in Pueblo:
Temperature Extremes of Summers Past
An overall warmer summer this year would also increase the likelihood of seeing record highs.
For Colorado Springs, the all-time record June temperatures is 101 degrees set on June 26, 2012, during the Waldo Canyon Fire, and again June 21, 2016. For July, the record is 100 degrees set on July 13, 1954 and July 24, 2003. And in August the record is 99, set August 3, 1954 and August 1, 2008.
For Pueblo, the all-time June record is 108 degrees set on June 29, 1990. For July, 109 on July 13, 2003. And in August the record is 105 which was set on August 2, 2008.
ENSO effects
In Colorado, the current ENSO (El Nino-Southern Oscillation) pattern certainly plays a role in our weather patterns, but it can become washed out with other variables like our distance from the ocean, terrain, and other atmospheric patterns.
That being said, La Nina is officially out and neutral ENSO conditions have returned to the central Pacific oceans. The current outlook shows neutral conditions remaining through summer, and La Nina may return by next fall/winter. A double La Nina also occurred during bad drought years in 2012 and 2018.
For summer weather, Peter Goble with the Colorado Climate Center says "Unfortunately for Colorado, there isn't a big difference historically between La Nina and neutral summers. In general, summer is the season in which ENSO (El Nino/La Nina) offers the least predictive skill."
What the trends do show is neutral/La Nina summers trend warmer than El Nino summers.
A more obvious influence may show up in the North American Monsoon that typically impacts Colorado in late summer. This is a time of year where we get a more direct tap into the east-central Pacific ocean waters. La Nina tends to suppress monsoon season, which we saw in 2020 as La Nina was forming.
El Nino typically brings the best monsoon rain and La Nina brings the least, with neutral conditions landing somewhere in between. Remaining at a neutral ENSO state through late summer then transitioning to La Nina into fall would likely bring another light monsoon.
