SPM 09-30-2019: High Winds and Fire Danger with Strengthening Low over the West Coast

Issue Date: Monday, September 30th, 2019
Issue Time: 9:50AM MDT

NOTE: This is the last scheduled State Precipitation Map of the 2019 season. It has been a pleasure to serve you! The next Flood Threat Bulletin season begins on May 1, 2020.

Summary:

The upper pattern remained the same from Saturday, but a strengthening low caused faster (southwest) surface winds over western Colorado with the tightening pressure gradient. This caused fire weather to return and placed a large area of the state under a Red Flag Warning due to fast winds paired with low relative humidity values. As winds mixed down to the surface, gusts between 45 and 65 mph were recorded. The highest gust was recorded at Garfield County airport (66 mph). There was some light rainfall over the Northwest Slope last night as higher PW values pushed into the area and combined with an upper level jet in favorable position for lift. Max 1-hour rain rates were under 0.25 inches, but totals up to 0.5 inches were estimated by MetStorm. A RAWS site near Dinosaur National Monument recorded 0.2 inches, which was the highest observation for the day.

Flooding was not reported on Sunday. To see estimated precipitation totals over your neighborhood the last couple of days, 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 vulnerable fire burn areas (post 2012), which are updated throughout the season to include new, vulnerable burn areas. The home button in the top left corner resets the map to the original zoom.

SPM 09-29-2019: Wind Gusts Were the Main Story

Issue Date: Sunday, September 29th, 2019
Issue Time: 9:00 AM MDT

Summary:

Caught between a strengthening low pressure along the West Coast and a high pressure system over the Southeast US, the tightened pressure gradient over Colorado resulted in strong, southwesterly flow aloft. These strong winds were mixed down towards the surface, and resulted in wind gusts in the 35-55 mph range at some of the higher mountain passes, with lower mountain valleys reporting gusts from 15-30 mph. Additionally, the strong, southwesterly flow forced the development of scattered showers over the San Juan Mountains and isolated showers over other northwest-to-southeast oriented mountain ranges west of the Continental Divide.

East of the mountains, it was a strengthening surface low over eastern Wyoming that brought southerly winds and warmer temperatures for most, with wind gusts generally 10-20 mph. A few gusts, mainly over the far eastern plains where the pressure gradient was strongest, were recorded at 25-35 mph.

No flash flooding was reported yesterday. For a look at precipitation estimates in your area, please see 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 vulnerable fire burn areas (post 2012), which are updated throughout the season to include new, vulnerable burn areas. The home button in the top left corner resets the map to the original zoom.

SPM 09-28-2019: Scattered Showers Dotted the State

Issue Date: Saturday, September 28th, 2019
Issue Time: 9:00 AM MDT

Summary:

Yesterday began with ample sunshine across Colorado, but clouds increased quickly during the afternoon/evening hours as an upper-level disturbance shifted across the Rockies. With this disturbance, scattered showers developed and moved from west-to-east, producing periods of light-to-moderate rainfall and gusty winds. The greatest coverage of rainfall occurred across northern Colorado where a bit more moisture was present, with more isolated coverage to the south. Showers diminished early this morning as the disturbance lifted out of the state and into Wyoming/Nebraska.

No flash flooding was reported yesterday. For a look at precipitation estimates in your area, please see 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 vulnerable fire burn areas (post 2012), which are updated throughout the season to include new, vulnerable burn areas. The home button in the top left corner resets the map to the original zoom.

SPM 09-27-2019: Light Rain for the Western Border & High Winds for the Northwest Corner of the State

Issue Date: Friday, September 27th, 2019
Issue Time: 10:10AM MDT

Summary:

Quite the dry air mass overhead yesterday with dew points mostly in the in the 30°Fs over western Colorado and 20°Fs over portions of the Central and eastern mountains. There were a couple pockets where dew points reached the low 40°Fs over the western border, which allowed some weak thunderstorms and rainfall to occur. Elsewhere, there was just an increase in cloud cover. Montezuma County saw a little rain, which is very much needed. CoCoRaHS in and around Cortez recorded around 0.15 inches. Storms produced an outflow gust of 33 mph around 5:30PM at the County Airport (KCEZ). Light rain also fell in northwest Montrose County and southwest Mesa County. Totals were slightly higher in the 0.25-0.30 inch range.

Wind gusts over northern Colorado (focused over the Northwest Slope) were the other weather story of the day. Gusts around 35 to 40 mph created dangerous fire conditions with RH in the teens. There were no new fires to report in this area as of this morning. The Hunt Fire in Rio Blanco County is 40% contained and has burned ~3,800 acres (last update Sep 15th). The Middle Man fire has burned about 275 acres. The most dangerous fire continues to the Decker Fire 9 miles south of Salida. It has burned 1,300 acres and has 118 personnel continuing to try to corral the fire. It has predominately burned within the Wilderness boundary, but is burning in an area with a lot of beetle kill (high-risk fuel).

To see estimated precipitation totals over your neighborhood the last couple of days, scroll down to the State Precipitation Map below. Note the bullseye over El Paso County just west of Colorado Springs is an error.

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 vulnerable fire burn areas (post 2012), which are updated throughout the season to include new, vulnerable burn areas. The home button in the top left corner resets the map to the original zoom.