SPM 07-28-2017: Heavy Rainfall Streak Alive And Well

Issue Date: Friday, July 28, 2017
Issue Time: 10:45AM MDT


The long streak of heavy rainfall days that we have witnessed in Colorado was alive and well on Thursday. Although rainfall coverage and intensity took a noticeable downtick compared to Wednesday, scattered to locally numerous activity was still observed. The highest concentration of storms during the afternoon was once again along the Palmer Ridge, stretching southward though the Southeast Mountains and Raton Ridge areas. Highest rain gage observations recorded about 1 inch of rainfall with most of that falling in about an hour or less. Radar-based estimates suggest up to 1.5 inches fell locally in these regions.

A secondary areas of high coverage was in the San Juan Mountains where up to 0.75 inches was common. Though, a few higher elevation SNOTEL sites measured over 1 inch of precipitation. A rock slide was reported in Hinsdale County in the late afternoon hours along Highway 30.

During the late evening hours, a few rogue storm cells crossed into northeast Colorado from Wyoming. These produced locally very heavy rain, to the tune of 2.25 inches per hour and up to 3.5 inches in a 90 minute period. A few flash flooding (and a severe thunderstorm) warnings accompanied this activity.

In all, a handful of Flash Flood warnings and Areal Flood advisories were issued for eastern Colorado yesterday afternoon and evening.

Finally, it will be amiss of us not to point out that the Great Sand dunes USGS gage measured 0.79 inches of rainfall yesterday. This represents about 10-12% of its annual average rainfall.

For rainfall estimates in your area, check out our new State Precipitation Map below.