SPM 09-23-2018: Fall Wildfire Weather Continues

Issue Date: Sunday, September 23rd, 2018
Issue Time: 09:35 AM MDT

Summary:

Saturday was seasonably warm and dry, with clear and sunny skies across Colorado. No precipitation was reported yesterday, save for two CoCoRaHS stations in Las Animas county that recorded less than 0.1 inches of rain overnight. Some areas of the state saw temperatures approaching record warmth as the unusual heat continued. Wildfires, particularly in the northwest and southwest parts of Colorado, continued to grow on Saturday. One of the largest fires in the state, the Ryan Fire in Jackson County, is still roughly 0% contained and grew to 3,000 acres yesterday. The Silver Creek fire near Kremmling is still not completely contained as well. The Bull Draw, Plateau, and Burro fires also are a major threat in the Southwest Slope, with the heat, wind, and now dead fall leaves making it difficult for firefighters to contain these strong blazes. No flooding or other storm reports were recorded yesterday.

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.

SPM 09-22-2018: Seasonably Warm with a Few Afternoon Showers in the Southeast

Issue Date: Saturday, September 22nd, 2018
Issue Time: 09:45 AM MDT

Summary:

The vast majority of the state was warm and dry yesterday. With high pressure continuing to build from the west, hot, low-humidity air from the southwest moved into the western parts of Colorado. Sunny and occasionally breezy weather was the story across the western slopes and the mountains through the afternoon. The eastern areas of the Raton Ridge and the very southern regions of the Southeast Plains had enough moisture present in the air to initiate some afternoon rain showers. In Prowers County, these showers were able to last long enough to drop over an inch of rain by the evening as indicated by radar. No local storm reports were recorded, and a few CoCoRaHS stations in Huerfano and Las Animas counties reported less than a tenth of an inch of rainfall, and in all no flooding was recorded on Friday.

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.

SPM 09-21-2018: Rainfall for Eastern Colorado as the Trough Continues Movement to the East

Issue Date: Friday, September 21st, 2018
Issue Time: 10:35 AM MDT

Summary:

The upper-level trough continued to push eastward through Colorado yesterday. Behind the trough, a very dry air mass filled into the area. It was such an arid air mass that there were no clouds present over the CO/UT border yesterday morning despite ongoing showers and cloud cover over the higher terrains throughout the night. Without much instability able to build over the western area of the eastern plains and only minimal low-level moisture, rain rates were light to moderate. Most totals over the Southeast Plains were in the 0.1 to 0.25 inch range. As you moved further east, a bit more instability was able to form, so storms were more convective in nature. A CoCoRaHS station outside of Springfield recorded 0.75 inches. Radar rainfall estimates over the CO/KS border were up to 1 inch. The higher totals were just over the border with radar estimates up to 1.75 inches. A second set of storms formed over the Northeast Plains associated with a surface low, but again, higher totals remained in Nebraska. Max 1-hr rain rates up to 0.2 were estimated by radar.

To see how much rain fell over your area yesterday, 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.

SPM 09-20-2018: Moisture Plume and Upper Dynamics Combine for Beneficial Rainfall

Issue Date: Thursday, September 20th, 2018
Issue Time: 10:05 AM MDT

Summary:

Quite an active weather day across the state yesterday. As the trough began to move eastward, a moisture plume was pulled northward into the state. With support of upper-level dynamics, including a cold front over eastern Colorado, widespread showers and thunderstorms returned to the forecast on Wednesday. Showers started over the southwest corner of the state and spread northward creating a line of storms oriented from southwest to northeast. Storms over western Colorado were generally lighter as not as much instability was able to build with storms starting during the late morning. Nonetheless, there was some beneficial rainfall for the San Juan and Central Mountains. Generally, totals were between 0.25 and 0.5 inches with lower elevations recording up to 0.1 inches. Even the San Luis Valley got some rainfall. Alamosa recorded around 0.5 inches with a CoCoRaHS station near San Luis recording 0.16 inches.

Over the eastern mountains, totals were greatest over the Front Range. As the storms moved into the adjacent plains (Urban Corridor) they encountered some decent instability and moisture. The Fort Collins Mesonet recorded its highest 24-hour value near Windsor, which was just over 1 inch. Radar rainfall estimates were just over 1.5 inches in the area due to CoCoRaHS stations in the area reporting 2.21 and 1.53 inches. There was some small hail reported with this storm, so we will look into these values as hail contamination might have occurred. Over Denver, the ALERT system had a 24-hour value of 1.26 inches at the Murphy Creek Golf Course site in Aurora. Totals over the metro area were mostly in the 0.3 to 0.7 inch range and produced a nice spike at the Cherry Creek gage (below). An areal flood advisory was issued for southeast Denver, Aurora and Centennial but there were no flood reports as of this morning. Over the eastern plains, storms became severe with a tornado warning in Kit Carson/Cheyenne Counties. Although the storm was capable of producing a tornado, there were no reports of a tornado as of this morning. Rainfall totals just over an inch were reported with these storms.

To see how much rain fell over your area yesterday, 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.