SPM 08-16-2018: Dry Air Causes Downtick in Heavy Rainfall Activity

Issue Date: Thursday, August 16th, 2018
Issue Time: 10:15 AM MDT

Summary:

Dry air associated with the upper-level trough was pushed into northern Colorado on Wednesday morning. This kept the northern half of the state pretty quiet during the afternoon hours. Residual moisture and a passing shortwave helped kick off some shower activity over the Central and San Juan Mountains. Though more cloud cover was apparent over the Central Mountains than wetting rains. Drier air kept rainfall totals over the San Juan Mountains in the 0.05 to 0.1 inch range as indicated by reporting SNOTEL and Mesonet stations. A bit heavier rainfall was present over the Southeast Mountains, Raton Ridge and Palmer Ridge. However, storms were quick to dissipate in the drier air as they moved off the higher terrains. Not much lightning associated with the widespread showers, so overall a nice soaking for the area. Some of the more convective storms over the adjacent plains produced rain rates just over 1 inch/hour, but after the bias correction, 24-hour totals were just under 1 inch.

A flash flood warning was issued for the Junkins burn scar and Spring Creek burn scar during the early evening hours. As of this morning, no flooding was reported. Radar estimated rainfall totals were up to 0.75 inches in the vicinity of the scars. To see how much precipitation fell over your area, scroll down to the 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 24-hour, 48-hour and 72-hour total precipitation contain bias corrections that are not disaggregated into the hourly estimates, so there will likely be some differences. The accumulation ending time is 7AM of the date shown in the bottom right corner. Also shown optionally are fire burn areas (post 2012), which are updated throughout the season to include new burn areas. The home button in the top left corner resets the map to the original zoom.