SPM 09-22-2022: Statewide, Late-Season Soaking Rain

Issue Date: Thursday, September 22nd, 2022
Issue Time: 11:00 AM MDT


The plume of late-season subtropical moisture mentioned in yesterday’s SPM post combined with upper-level forcing to produce a widespread soaking rain over Colorado on the last full day of astronomical summer. In anticipation of this event, WFOs issued Flood Watches for most areas west of the Divide and along/south of I-70, although no warnings or advisories ended up being issued. The rain was more stratiform and steady in nature rather than convective and intense, which precluded flash flooding from occurring. Nonetheless, some locations did experience embedded convection and briefly heavier rainfall rates.

Several rivers and creeks in the mountains are running at all-time highs for this day of the year, including the Uncompahgre River near Ouray, Lincoln Creek near Aspen, the East Fork of the Eagle River near Climax, and Troublesome Creek near Troublesome, although no flooding has been reported.

QPE data suggests widespread amounts of 0.25-0.75” along and west of the Divide, with locally higher amounts of 1-2+” for the higher elevations of the Central Mountains and especially the San Juan Mountains/Southwest Slope. Notable rain gauge observations include:

• 2.22” west-northwest of Durago
• 1.92” south of Durango
• 1.57” southeast of Cortez
• 1.55” near Rico
• 1.48” near Mancos
• 1.23” near Cahone

East of the Divide across the Front Range and Urban Corridor, general amounts of 0.25-0.75” were observed, with the heaviest amounts closer to 0.75” reported in the Fort Collins vicinity. The eastern Northeast Plains experienced the heaviest rainfall of the entire state, with QPE data suggesting amounts of 1.5-2.5+” across the counties of Yuma, Logan, Sedgwick, and Phillips. Notable rain gauge observations here include:

• 1.93”, 1.71″, 1.70”, and 1.63” near Holyoke
• 1.48” near Idalia
• 1.40” near Fairfield
• 1.27” near Haxtun
• 1.23” near Crook
• 1.23” near Vernon

No flooding was reported yesterday. For precipitation estimates in our area, check out the map below. Remember, if you observe flooding in your area, you can use the “Report a Flood” page to make a flood report when you can safely do so.

Click Here For Map Overview

The map below shows radar-estimated, rainfall gage-adjusted Quantitative Precipitation Estimates (QPE) across Colorado. The map is updated daily during the operational season (May 1 – Sep 30) by 11AM. The following six layers are currently available: 24-hour, 48-hour and 72-hour total precipitation, as well as maximum 1-hour, 2-hour and 6-hour precipitation over the past 24 hour period (to estimate where flash flooding may have occurred). The accumulation ending time is 7AM of the date shown in the bottom right corner. Also shown optionally are vulnerable fire burn areas (post 2012), which are updated throughout the season to include new, vulnerable burn areas. The home button in the top left corner resets the map to the original zoom.