SPM 06-08-2018: Isolated Showers and Thunderstorms for Eastern Colorado

Issue Date: Friday, June 8, 2018
Issue Time: 09:20AM MDT

Summary:

Quiet weather day across Colorado with the exception of a few isolated thunderstorms over the Palmer Ridge in the afternoon. Dry southwest flow limited moisture availability for all storms that formed yesterday, and they were outflow dominant. Most storms that fired over the mountains quickly evaporated in the dry air. As expected the temperature/dew point spread produced gusty winds and limited rainfall for the storms that were able to move into the adjacent plains. The ASOS station at Colorado Springs airport reported a gust of 32 mph with radar rainfall estimates up to 0.5 inches in the area. The largest rainfall total from yesterday was near Pueblo where radar rainfall was estimated to be around 1 inch. Thunderstorms attempted to move into the far eastern plains, but they were not able to quite make it to the unstable environment before sundown. All storm action ended by 9:30PM on Thursday.

Flooding was not reported on Thursday. For rainfall estimates 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 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.

SPM 06-07-2018: Late Afternoon Severe Weather for the Eastern Plains and Heavy Rainfall for Yuma County

Issue Date: Thursday, June 7, 2018
Issue Time: 10:25AM MDT

Summary:

A cold front moved through the northeast corner of the state Wednesday morning helping shift winds and slightly moisten the lower levels of the atmosphere a bit under the otherwise strong, dry ridge. The front eventually stalled out over the Palmer Divide by late morning. By mid-afternoon, a Denver cyclone had formed east of the Urban Corridor. Strong easterly winds on the north side helped increase dew points into the mid and upper 50Fs over the Northeast Plains. On its east side, a line of convergence and a passing shortwave helped trigger numerous severe thunderstorms over the Northeast Plains. Outflow boundaries from these storms helped provide additional lift for more thunderstorm development in the moist, high CAPE environment.

The severe thunderstorms over the Northeast Plains produced large hail and gusty winds. The largest hail stone was reported in Logan County where the 4 inch diameter stone (softball size) blew out the windshield of a trained spotter – yikes! Gusts between 55-60 mph were also commonplace under these storms. An areal flood advisory was issued for northern Logan and Sedgwick Counties around 8PM for a nearly stationary thunderstorm along a boundary. 1-hour rain rates were estimated at 2 inches with totals just above 2.5 inches. The boundary slowly sagged south and more thunderstorms developed along the line (to the west) producing very heavy rainfall that trigged two more areal flood advisories. The town of Yuma reported 1.69 inches of rainfall and street flooding. Radar estimates were over 4 inches in the area, and a CoCoRaHS station recorded 2.76 inches just north of town. If estimates are correct, that’s about a 1 in 200 year storm for this area. Storms eventually moved out of the state by 2AM.

Over the Front Range and Urban Corridor, storms began to fire over the higher terrains by 3PM and continued into the evening. Due to the lack of moisture, these storms were high-based and produced little rainfall. However, multiple rounds of pulse-like convection was able to produce 24-hour rainfall amounts up to 0.3 inches over Fool Creek outside of Winter Park at a SNOTEL site. An evening thunderstorm rolled off the mountains into Denver around 8PM and produced gusty winds. A mesonet station in Ken Caryl reported a gust of 58 mph. Total rainfall amounts were under 0.2 inches.

For rainfall estimates 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 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.

SPM 06-06-2018: Widespread Record- and Near-Record Heat with a few Overachieving Thunderstorms

Issue Date: Wednesday, June 6, 2018
Issue Time: 10:35AM MDT

Summary:

Yesterday marked the hottest day of the year so far for many in Colorado, with a number of stations approaching or breaking their record high temperatures for the day. The image below shows the high temperatures at stations across Colorado yesterday, ranging from 70°Fs in the mountains to over 100°F in a few spots on the eastern plains! In addition, the righthand panel shows how temperatures at 4:00pm MDT yesterday compared to the records for the day, with many stations nearing (within 3°F, in yellow), tying (orange), or breaking (red) their daily record highs. Notice that the heat was particularly prominent on the eastern plains.

 

In addition to the heat, some thunderstorms were observed over the eastern plains yesterday evening. While little in the way of thunderstorm activity occurred near the typical afternoon peak across the state, a cluster of storms fired up across Kit Carson, Yuma, and Cheyenne counties around 9:00pm last night. These storms lingered across extreme eastern Colorado until almost 4:00am, producing up to 0.48” of rain at gauge sites with a radar-estimated maximum near 1.5”.

No flooding was reported on Tuesday. For rainfall estimates 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 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.

SPM 06-05-2018: A Return to Warm and Dry Conditions Throughout Colorado

Issue Date: Tuesday, June 5, 2018
Issue Time: 10:50AM MDT

Summary:

The heat returned yesterday in Colorado, with the winds shifting to a more southwesterly direction as the large upper atmosphere ridge that will bring dry and hot weather for the entire week began to move over the area. Clouds increased throughout the day along the Front Range, Urban Corridor, and across the eastern plains. Plenty of virga could be seen in the late afternoon, as well as gusty winds within the outflow of nearby thunderstorms. Throughout the state, there were very few gauges that recorded measurable rainfall. Oddly, the area with most of these gauges was in and around the San Luis Valley, which is climatologically one of the driest regions in Colorado. Here, afternoon thunderstorms had just enough strength to drop small amounts of rainfall. No flooding was reported 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 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.