State Precipitation Map

STP 08-21-2016: A Few Heavy “Rainers” in the Sangre De Christos and San Juans; Taste of Fall Elsewhere

August 21, 2016 by Dima Smirnov ·

Issue Date: Sunday, August 21st, 2016
Issue Time: 9:10AM MDT

Summary

Residual moisture combined with the still-strong August sun fueled scattered thunderstorm activity in the southern parts of Colorado on Saturday. The climatologically favored regions of the Sangre de Cristo and San Juan mountain were the beneficiaries of this activity. Although the highest observed 24-hour rainfall amounts were only about 0.75 inches (only 0.40 inches on CoCoRaHS), higher totals were estimated between gages. Radar estimated amounts of about 1.5 inches were noted on isolated portions of the San Juan mountains. Two flood advisories were issued: one for Mineral County and another for Las Animas County. A flash flood warning was issued as a precaution for the Hayden Pass burn scar area. Fortunately, no flooding reports were received this morning.

In addition to the rainfall aspect, a few severe thunderstorm warnings were also posted for hail and high winds. Observed hail reports up to 1.0 inch were reported in Custer and Archuleta counties. The most severe storm was likely a slow moving cell over Las Animas county though this took place over rural terrain and did not garner any observations.

Meanwhile, for the rest of the state, especially east of the Continental Divide, it felt like fall with high temperatures running up to 15F below their seasonal normal. This was a one day event, with summer back in full swing on Sunday.

For rainfall estimates specific to your area, check out our Storm Total Precipitation map below.

Filed Under: State Precipitation Map ·

STP 08-20-2016: Impressive Cool Front Preceded by Heavy Rainfall and Severe Weather

August 20, 2016 by Dima Smirnov ·

Issue Date: Saturday, August 20th, 2016
Issue Time: 9:00AM MDT

Summary

A fall-like cool, or even cold-front raced south-southeast out of Montana and Wyoming and crossed into Colorado by mid-afternoon on Friday. Prior to the cool front passage, mostly clear skies resulted in ample instability for many areas east of the Continental Divide. Thunderstorms erupted early along the higher terrain of the Front Range and eventually congealed into a complex that quickly moved southeastward. Plenty of short-term heavy rain rates were observed. For example, a Fort Collins ALERT gage picked up 0.79 inches in less than 30 minutes, several Urban Drainage and Flood Control District gages received between 0.6 and 0.8 inches in 30 minutes (including 0.5 inches in 10 minutes) and a USGS gage in El Paso county received over 1.5 inches per hour. While most of the rainfall was too short-term to cause any flooding issues, two flood-related alerts were posted: a Flood Advisory near Highlands Ranch and a Flash Flood Warning just northeast of Colorado Springs. The only official flooding report this morning was received from near Peyton where flooded roads were noted.

In addition to the heavy rainfall, plenty of hail and high wind reports were also tallied. By far the most impressive storm of the day originated just northeast of Fort Collins and then trekked for over 100 miles southeastward while causing many hail reports up to 1 inch (higher sizes probably fell but were not observed) and wind speeds up to 81 mph. You can see the trail of the storm in the map below from Iowa State University, showing the numerous severe thunderstorm warnings that it tallied (in yellow).

Meanwhile, on the western slope, the weather was much quieter on Friday. A few scattered showers and weak thunderstorms were seen but rainfall amounts were limited to about 0.25 inches except for a few higher amounts in the San Juans.

For rainfall estimates specific to your area, check out our Storm Total Precipitation map below.

Filed Under: State Precipitation Map ·

STP 08-19-2016: Another Day Of Widespread Light To Moderate Rainfall

August 19, 2016 by Dima Smirnov ·

Issue Date: Friday, August 19th, 2016
Issue Time: 9:00AM MDT

Summary

Widespread light to moderate rainfall fell across many parts of Colorado on Thursday, thanks to a large disturbance approaching the state from the southwest. Precipitable water values rose gradually into the 0.8 – 0.9 inch range, support localized areas of heavy rainfall. The main limiting factor was instability, as a good deal of the moisture was located above the boundary layer making it less effective in feeding thunderstorm updrafts. Nonetheless, rainfall amounts of 0.25 to 0.5 inches over an hour or two were common across many parts of the San Juans, Central Mountains, Southeast Mountains, Front Range and Urban Corridor. The highest 24-hour CoCoRaHS total came in at 1.02 inches from La Plata county, though higher amounts up to 2 inches likely occurred between rain gages. Most rainfall fell during the afternoon and early evening hours, but light to moderate showers were ongoing in the Southeast Plains overnight.

A few stronger storms were noted along the Cheyenne Ridge near the Wyoming border with up to 1.5 inches of rainfall falling in Weld County. Fortunately, no severe weather reports were received from this activity, though it’s possible that there was no one there to see it.

No official flood reports were received as of this morning, however two Areal Flood Advisories were issued on Thursday afternoon: one just north of Grand Junction near I-70, and another for parts of Rocky Mountain National Park.

For rainfall estimates specific to your area, check out our Storm Total Precipitation map below.

Filed Under: State Precipitation Map ·

STP 08-18-2016: Showers/Storms Favored the Higher Terrain

August 18, 2016 by COfloodthreat ·

Issue Date: Thursday, August 18th, 2016
Issue Time: 9:00 AM MDT

Summary:

With a mostly disorganized upper-level pattern, showers and thunderstorms relied largely on terrain influences and weak surface convergence to drive yesterday’s activity. Showers/storms favored the higher terrain, especially across the western third of the state where better support from the mid-/upper-level trough could be found. Widely scattered showers/storms also developed across the lower elevations of eastern Colorado as weak surface convergence developed along/near the Palmer Ridge. Nearly all storms were garden variety, as the environment could not quite develop the punch needed for heavy rainfall.

Rainfall winners, according to CoCoRaHS observations (reports as of 7:00 AM MDT):

Saguache County: 0.59 inches
Fremont County: 0.36 inches
Pueblo County: 0.35 inches
Lake County: 0.31 inches

For a statewide look at 24-hour precipitation totals, please take a look at the Storm Total Precipitation map below.

Filed Under: State Precipitation Map ·