SPM 10-01-2022: Heavy Precipitation for Northwest Half of State

Issue Date: Saturday, October 1, 2022
Issue Time: 9:45 AM MDT


All good things must come to an end, but we sure had an active day of weather for the last SPM post of the 2022 season. Thanks to a cut-off upper-level low spinning over the northern Great Basin, scattered showers and storms overspread much of the northwestern half of the state on Friday. The heaviest rain was observed along and northwest of a line from roughly Durango to Sterling, while the southeastern half of the state remained largely dry.

Amounts of 0.25-0.75” were fairly commonplace where precipitation was observed, with locally higher amounts of 1-2+”. Stronger storms were observed along the western I-70 corridor near Grand Junction, prompting two Severe Thunderstorm Warnings and two Flood Advisories. No flooding was reported, but 0.25” hail was reported in Grand Junction. Mammatus clouds were even observed:

Notable rainfall totals include the following:

• 2.80” near Paonia State Park
• 2.26”, 2.15”, and 1.81” east of Glenwood Springs
• 1.42” near Grand Mesa
• 1.16”, 1.10”, and 1.02” near Grand Junction
• 1.13” east of New Castle
• 0.98” southeast of Rifle

Some of the highest mountain elevations (10,000+ feet) experienced their precipitation in the form of snowfall yesterday:

Several USGS gauges in the Central and Northern Mountains are running at all-time highs for this day of the year thanks to yesterday’s rain, but no flooding was reported. 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.

As alluded to above, this will be the last SPM post until next season. It has been a pleasure providing these daily posts for the state of Colorado throughout the 2022 flood season.

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.