SPM 08-17-2017: Rainfall Coverage and Intensity Decreased

Issue Date: Thursday, August 17, 2017
Issue Time: 9:35AM MDT

Summary:

With drier air slowly infiltrating into Colorado from the west, rainfall coverage and intensity decreased on Wednesday compared to Tuesday. Even so, scattered showers and thunderstorms still popped up, mainly limited to east of the Continental Divide. However, storms were smaller in size and were being steered by relatively strong winds. Thus, even the highest precipitation amounts were limited to about 0.75 inches over parts of El Paso and Cheyenne counties. Interestingly, very heavy rainfall was still noted, though only for a very short period of time. For example, an Urban Drainage and Flood Control District gage near Boulder picked up about 0.3 inches in 10 minutes (equivalent to a 1.8 inch per hour intensity).

Elsewhere, a cool frontal passage limited high temperatures to 5 – 10F below normal east of the Continental Divide. Meanwhile, to the west, seasonable temperatures with some afternoon sunshine was the rule.

Finally, it should be noted that the Arkansas River, the focal point of some very impressive rainfall over the past month, continued to recede and is now below Action levels at all major USGS gage sites.

Flooding was not reported on Wednesday. For rainfall estimates in your area, check out our State Precipitation Map below.

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 6AM of the date shown in the bottom right corner. Also shown optionally are fire burn areas since 2012. The home button in the top left corner resets the map to the original zoom.

Note: We have identified a possible underestimation in QPE over the southwest part of the state. We are working to on this issue, and will provide an update as soon as possible.