Alerts from NWS Denver/Boulder CO (UNOFFICIAL)

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Unofficial bot sharing alerts from NWS Denver/Boulder CO. This account is not monitored. Contact @wandrme.paxex.aero if needed.

The storms which prompted the warning have weakened below severe limits, and no longer pose an immediate threat to life or property. Therefore, the warning will be allowed to expire. However, gusty winds are still possible with these thunderstorms.
At 921 PM MDT, severe thunderstorms were located along a line from near Westplains to near Fleming, or along a line from 25 miles northwest of Sterling to 20 miles east of Sterling, moving northeast at 10 mph. HAZARD...60 mph wind gusts and small hail. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. Locations impacted include... Sedgwick, Crook and Twin Buttes.
At 907 PM MDT, severe thunderstorms were located along a line from over Westplains to 4 miles south of Fleming, or along a line from 25 miles northwest of Sterling to 18 miles east of Sterling, moving northeast at 10 mph. HAZARD...60 mph wind gusts and small hail. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. Locations impacted include... Fleming, Iliff, Peetz, Sedgwick, Crook, Proctor and Twin Buttes.
SVRBOU The National Weather Service in Denver has issued a * Severe Thunderstorm Warning for... Northeastern Logan County in northeastern Colorado... Western Sedgwick County in northeastern Colorado... * Until 945 PM MDT. * At 856 PM MDT, severe thunderstorms were located along a line from near Westplains to 5 miles west of St Petersburg, or along a line from 25 miles northwest of Sterling to 15 miles east of Sterling, moving northeast at 10 mph. HAZARD...60 mph wind gusts and small hail. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. * Locations impacted include... Fleming, Iliff, Peetz, Sedgwick, Crook, Proctor, Padroni, Twin Buttes and Westplains.
FFWBOU The National Weather Service in Denver has issued a * Flash Flood Warning for... Northeastern Lincoln County in east central Colorado... * Until 1145 PM MDT. * At 848 PM MDT, Doppler radar and automated rain gauges indicated thunderstorms producing heavy rain across the warned area. Between 1.5 and 4 inches of rain have fallen. The expected rainfall rate is 1.5 to 2.5 inches in 1 hour. Flash flooding is ongoing or expected to begin shortly. HAZARD...Flash flooding caused by thunderstorms. SOURCE...Radar and automated gauges. IMPACT...Flash flooding of small creeks and streams, gulches, roads, and poor drainage and low-lying areas. * Some locations that will experience flash flooding include... Hugo, Arriba and Genoa. This includes the following streams and drainages... Hell Creek, Dugout Creek, South Fork Republican River, Long Creek, Big Sandy Creek and Sevenmile Creek.
* WHAT...Urban area and small stream flooding caused by excessive rainfall is expected. * WHERE...South Central Logan County in northeastern Colorado... * WHEN...Until 1045 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Water over roadways. Overflowing poor drainage areas. * ADDITIONAL DETAILS... - At 843 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. This may cause urban and small stream flooding. Between 1 and 1.5 inches of rain have fallen. - Additional rainfall amounts up to 0.5 inches are expected over the area. This additional rain will result in minor flooding. - Some locations that will experience flooding include... Sterling, Merino and Atwood.
At 833 PM MDT, severe thunderstorms were located along a line from near North Sterling Reservoir to 7 miles southwest of Fleming, or along a line from 14 miles north of Sterling to 14 miles east of Sterling, moving northeast at 25 mph. HAZARD...70 mph wind gusts and quarter size hail. SOURCE...Weather station reported. IMPACT...Hail damage to vehicles is expected. Expect considerable tree damage. Wind damage is also likely to mobile homes, roofs, and outbuildings. Locations impacted include... Northeastern Sterling, Fleming, Iliff, Peetz, Crook, Proctor, Padroni, North Sterling Reservoir and Reiradon Hill.
SVRBOU The National Weather Service in Denver has issued a * Severe Thunderstorm Warning for... Central Logan County in northeastern Colorado... * Until 900 PM MDT. * At 818 PM MDT, severe thunderstorms were located along a line from 4 miles southwest of North Sterling Reservoir to 12 miles north of Burdett, or along a line from 11 miles northwest of Sterling to 11 miles southeast of Sterling, moving northeast at 25 mph. HAZARD...60 mph wind gusts. SOURCE...Weather station reported. IMPACT...Expect damage to roofs, siding, and trees. * Locations impacted include... Eastern Sterling, Fleming, Iliff, Peetz, Crook, Proctor, Padroni, North Sterling Reservoir and Reiradon Hill.
At 815 PM MDT, severe thunderstorms were located along a line from 6 miles southwest of North Sterling Reservoir to 6 miles north of Burdett, or along a line from 11 miles northwest of Sterling to 15 miles southeast of Sterling, moving northeast at 25 mph. HAZARD...60 mph wind gusts and small hail. SOURCE...Weather station reported. IMPACT...Expect damage to roofs, siding, and trees. Locations impacted include... Sterling, Atwood, Logan Corners and Reiradon Hill.
* WHAT...Flooding caused by excessive rainfall continues. * WHERE...Northeastern Lincoln County in east central Colorado... * WHEN...Until 1100 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 820 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms, with additional thunderstorms moving into the area. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 1 and 2 inches of rain have fallen. - This includes the following streams and drainages... Hell Creek and Dugout Creek. - Some locations that will experience flooding include... Mainly rural areas of Northeastern Lincoln County.
At 800 PM MDT, severe thunderstorms were located along a line from over Pawnee Pass to 5 miles northwest of Platner, or along a line from 15 miles west of Sterling to 6 miles northeast of Akron, moving northeast at 15 mph. HAZARD...60 mph wind gusts and small hail. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. Locations impacted include... Sterling, Merino, Atwood, Logan Corners, Willard, Pawnee Pass, Burdett and Reiradon Hill.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...North Central Lincoln County in east central Colorado... * WHEN...Until 1100 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 807 PM MDT, Doppler radar indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 0.5 and 1.5 inches of rain have fallen. - This includes the following streams and drainages... Lake Creek, Currie Creek, Hell Creek, Dugout Creek and Big Sandy Creek. - Some locations that will experience flooding include... Limon.
SVRBOU The National Weather Service in Denver has issued a * Severe Thunderstorm Warning for... Southwestern Logan County in northeastern Colorado... Northeastern Morgan County in northeastern Colorado... Northeastern Washington County in northeastern Colorado... * Until 830 PM MDT. * At 744 PM MDT, severe thunderstorms were located along a line from near Pawnee Pass to over Akron, or along a line from 18 miles west of Sterling to over Akron, moving northeast at 15 mph. HAZARD...60 mph wind gusts and small hail. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. * Locations impacted include... Sterling, Akron, Merino, Atwood, Prewitt Reservoir, Logan Corners, Willard, Pawnee Pass, Burdett, Messex, Fremont Butte and Reiradon Hill.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...East Central Lincoln County in east central Colorado... * WHEN...Until 1015 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. * ADDITIONAL DETAILS... - At 718 PM MDT, Doppler radar indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 0.5 and 1 inch of rain has fallen. - This includes the following streams and drainages... Coon Creek, Hell Creek, South Fork Republican River, Big Sandy Creek and Sevenmile Creek. - Some locations that will experience flooding include... Hugo and Genoa.
The storm which prompted the warning has weakened below severe limits, and no longer poses an immediate threat to life or property. Therefore, the warning will be allowed to expire. However, gusty winds are still possible with this thunderstorm.
At 703 PM MDT, a severe thunderstorm was located 8 miles north of Snyder, or 17 miles northeast of Fort Morgan, moving north at 20 mph. HAZARD...60 mph wind gusts and quarter size hail. SOURCE...Radar indicated. IMPACT...Hail damage to vehicles is expected. Expect wind damage to roofs, siding, and trees. Locations impacted include... Akron, Hillrose, Midway, Snyder, Fremont Butte, Union and Messex.
* WHAT...Flooding caused by excessive rainfall continues. * WHERE...East Central Lincoln County in east central Colorado... * WHEN...Until 915 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 701 PM MDT, Doppler radar indicated heavy rain due to thunderstorms, with additional thunderstorms currently entering the area. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 1 and 2 inches of rain have fallen. - This includes the following streams and drainages... South Fork Republican River and Hell Creek. - Some locations that will experience flooding include... Arriba.
* WHAT...Flooding caused by excessive rainfall continues. * WHERE...Northeastern Lincoln County in east central Colorado... * WHEN...Until 845 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 658 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms, with additional thunderstorms entering the area. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 1 and 2 inches of rain have fallen. - This includes the following streams and drainages... Hell Creek and Dugout Creek. - Some locations that will experience flooding include... Mainly rural areas of Northeastern Lincoln County.
At 651 PM MDT, a severe thunderstorm was located over Snyder, or 12 miles east of Fort Morgan, moving north at 20 mph. HAZARD...60 mph wind gusts and half dollar size hail. SOURCE...Radar indicated. IMPACT...Hail damage to vehicles is expected. Expect wind damage to roofs, siding, and trees. Locations impacted include... Akron, Brush, Hillrose, Midway, Gary, Snyder, Fremont Butte, Union and Messex.
SVRBOU The National Weather Service in Denver has issued a * Severe Thunderstorm Warning for... Eastern Morgan County in northeastern Colorado... Western Washington County in northeastern Colorado... * Until 730 PM MDT. * At 641 PM MDT, a severe thunderstorm was located near Brush, or 12 miles east of Fort Morgan, moving north at 25 mph. HAZARD...60 mph wind gusts and quarter size hail. SOURCE...Radar indicated. IMPACT...Hail damage to vehicles is expected. Expect wind damage to roofs, siding, and trees. * Locations impacted include... Akron, Brush, Hillrose, Midway, Gary, Woodrow, Snyder, Fremont Butte, Union and Messex.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...East Central Lincoln County in east central Colorado... * WHEN...Until 915 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 616 PM MDT, Doppler radar indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 0.5 and 1.5 inches of rain have fallen. - This includes the following streams and drainages... South Fork Republican River and Hell Creek. - Some locations that will experience flooding include... Arriba.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...Northeastern Lincoln County in east central Colorado... * WHEN...Until 845 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 537 PM MDT, Doppler radar indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 1 and 1.5 inches of rain have fallen. - This includes the following streams and drainages... Hell Creek, Hackberry Creek, and Dugout Creek. - Some locations that will experience flooding include... Mainly rural areas of Northeastern Lincoln County.
The Flood Advisory will expire at 515 PM MDT this afternoon for a portion of north central Colorado, including the following area, Larimer County. The heavy rain has ended. Flooding is no longer expected to pose a threat. However, additional showers and thunderstorms are still possible this evening. Please continue to heed any remaining closures.
The storm which prompted the warning has weakened below severe limits, and no longer poses an immediate threat to life or property. Therefore, the warning will be allowed to expire. However, gusty winds are still possible with this thunderstorm.
At 440 PM MDT, Doppler radar and automated rain gauges indicated ongoing thunderstorms producing moderate to heavy rain across the warned area. Between 2 and 3.5 inches of rain have fallen. Flash flooding is ongoing or expected to begin shortly. HAZARD...Flash flooding caused by thunderstorms. SOURCE...Radar and automated gauges. IMPACT...Flash flooding of small creeks and streams, gulches, roads, and poor drainage and low-lying areas. Some locations that will experience flash flooding include... Pine Junction, Pine Grove and Shaffers Crossing.
At 425 PM MDT, a severe thunderstorm was located over D.I.A Terminal and Concourses, or 18 miles northeast of Denver, moving northeast at 15 mph. HAZARD...60 mph wind gusts. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. This severe thunderstorm will be near... Denver International Airport, D.I.A Terminal and Concourses, Commerce City, Denver and Aurora around 430 PM MDT.
At 402 PM MDT, Heavy rain has currently ended in the area. However, additional showers and thunderstorms are expected this afternoon. Between 1.5 and 3 inches of rain have fallen. Flash flooding is ongoing or expected to begin shortly. HAZARD...Flash flooding caused by thunderstorms. SOURCE...Radar and automated gauges. IMPACT...Flash flooding of small creeks and streams, gulches, roads, and poor drainage and low-lying areas. Some locations that will experience flash flooding include... Pine Junction, Pine Grove and Shaffers Crossing.
* WHAT...Flooding caused by excessive rainfall continues. * WHERE...South Central Larimer County in north central Colorado... * WHEN...Until 615 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 408 PM MDT, Thunderstorms are ongoing in the area, with moderate to heavy rainfall at times. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 1 and 1.5 inches of rain have fallen. - Some locations that will experience flooding include... Estes Park.
The Colorado Department of Public Health and Environment has issued the following... WHAT...Ozone Action Day Alert. WHERE...Douglas, Jefferson, Denver, western Arapahoe, western Adams, Broomfield, Boulder, Larimer, and Weld Counties WHEN...400 PM Wednesday July 22 to 1200 AM Thursday July 23 IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Ozone levels are expected to reach the Unhealthy for Sensitive Groups category in the Denver Metro area on Wednesday. Increased chances of afternoon thunderstorms are expected to keep ozone in the Good to Moderate range on Thursday. For Colorado air quality conditions, forecasts, and advisories, visit: https://www.colorado.gov/airquality/colorado_summary.aspx If possible, please help us reduce ozone pollution by limiting driving gas and diesel-powered vehicles until midnight, Wednesday night, July 22, 2026. Colorado is also addressing ozone pollution through state policies. For more information about health impacts and how ozone pollution forms in Colorado, visit: https://cdphe.colorado.gov/ozone- pollution-and-your-health HEALTH INFORMATION...Increasing likelihood of respiratory symptoms and breathing discomfort in active children and adults and people with lung disease, such as asthma. Active children and adults, and people with lung disease, such as asthma, should reduce prolonged or heavy outdoor exertion.
SVRBOU The National Weather Service in Denver has issued a * Severe Thunderstorm Warning for... Western Adams County in northeastern Colorado... Central Arapahoe County in northeastern Colorado... Northeastern Denver County in northeastern Colorado... Southern Weld County in northeastern Colorado... * Until 445 PM MDT. * At 413 PM MDT, a severe thunderstorm was located near D.I.A Terminal and Concourses, or 15 miles east of Denver, moving northeast at 15 mph. HAZARD...60 mph wind gusts. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. * Locations impacted include... Northeastern Denver, northeastern Aurora, northeastern Commerce City, Brighton, Denver International Airport, D.I.A Terminal and Concourses, Lochbuie, Watkins and Barr Lake.
* WHAT...Flooding caused by excessive rainfall continues. * WHERE...Central Larimer County in north central Colorado... * WHEN...Until 515 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 329 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. While thunderstorms have currently left the area, additional storms are expected later this afternoon. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 0.5 and 1.5 inches of rain have fallen. - Some locations that will experience flooding include... Rustic.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...South Central Larimer County in north central Colorado... * WHEN...Until 615 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 319 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 1 and 1.5 inches of rain have fallen. - Additional rainfall amounts of 0.5 to 1 inch are expected over the area. This additional rain will result in minor flooding. - Some locations that will experience flooding include... Estes Park.
FFWBOU The National Weather Service in Denver has issued a * Flash Flood Warning for... West Central Jefferson County in central Colorado... Northeastern Park County in central Colorado... * Until 600 PM MDT. * At 310 PM MDT, Doppler radar and automated rain gauges indicated thunderstorms producing heavy rain across the warned area. Between 1.5 and 3 inches of rain have fallen. Flash flooding is ongoing or expected to begin shortly. HAZARD...Flash flooding caused by thunderstorms. SOURCE...Radar and automated gauges. IMPACT...Flash flooding of small creeks and streams, gulches, roads, and poor drainage and low-lying areas. * Some locations that will experience flash flooding include... Pine Junction, Pine Grove and Shaffers Crossing.
* WHAT...Small stream flooding caused by excessive rainfall continues. * WHERE...South Central Larimer County in north central Colorado... * WHEN...Until 430 PM MDT. * IMPACTS...Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 251 PM MDT, Doppler radar indicated heavy rain continuing due to thunderstorms. This may cause small stream flooding. Between 1 and 1.5 inches of rain have fallen. - Some locations that will experience flooding include... Pingree Park.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...West Central Jefferson County in central Colorado... Northeastern Park County in central Colorado... * WHEN...Until 530 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. * ADDITIONAL DETAILS... - At 236 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 0.5 and 1.5 inches of rain have fallen. - Some locations that will experience flooding include... Pine Junction, Bailey, Pine Grove, Shaffers Crossing and Glenisle.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...Central Larimer County in north central Colorado... * WHEN...Until 515 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 209 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 0.5 and 1.5 inches of rain have fallen. - Some locations that will experience flooding include... Rustic.
* WHAT...Small stream flooding caused by excessive rainfall is expected. * WHERE...South Central Larimer County in north central Colorado... * WHEN...Until 430 PM MDT. * IMPACTS...Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 122 PM MDT, Doppler radar indicated heavy rain due to thunderstorms. This may cause small stream flooding. Between 0.5 and 1.5 inches of rain have fallen. - Some locations that will experience flooding include... Pingree Park. - Pennock Creek, Fall Creek, West Creek.
The Colorado Department of Public Health and Environment has issued the following... WHAT...Ozone Action Day Alert. WHERE...Douglas, Jefferson, Denver, western Arapahoe, western Adams, Broomfield, Boulder, Larimer, and Weld Counties WHEN...400 PM Tuesday July 21 to 400 PM Wednesday July 22 IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Hot and sunny weather with limited chances for afternoon storms will allow ozone concentrations to reach the Unhealthy for Sensitive Groups category on Tuesday and Wednesday. On Tuesday elevated ozone is possible in the Denver Metro area, Fort Collins, Greeley, and surrounding areas. On Wednesday the highest ozone is expected to be confined to locations within the Denver Metro area. For Colorado air quality conditions, forecasts, and advisories, visit: https://www.colorado.gov/airquality/colorado_summary.aspx If possible, please help us reduce ozone pollution by limiting driving gas and diesel-powered vehicles until at least 4 p.m. Wednesday, July 22, 2026. Colorado is also addressing ozone pollution through state policies. For more information about health impacts and how ozone pollution forms in Colorado, visit: https://cdphe.colorado.gov/ozone- pollution-and-your-health HEALTH INFORMATION...Increasing likelihood of respiratory symptoms and breathing discomfort in active children and adults and people with lung disease, such as asthma. Active children and adults, and people with lung disease, such as asthma, should reduce prolonged or heavy outdoor exertion.
SVRBOU The National Weather Service in Denver has issued a * Severe Thunderstorm Warning for... Eastern Larimer County in north central Colorado... West Central Weld County in northeastern Colorado... * Until 1230 AM MDT. * At 1202 AM MDT, a severe thunderstorm was located over Wellington, or 11 miles northeast of Fort Collins, moving northeast at 15 mph. HAZARD...60 mph wind gusts and quarter size hail. SOURCE...Radar indicated. IMPACT...Hail damage to vehicles is expected. Expect wind damage to roofs, siding, and trees. * Locations impacted include... Northeastern Fort Collins, Wellington, Nunn and Waverly.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...East Central Larimer County in north central Colorado... * WHEN...Until 300 AM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Ponding of water in urban or other areas is occurring or is imminent. * ADDITIONAL DETAILS... - At 1153 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 0.5 and 1.5 inches of rain have fallen. - Some locations that will experience flooding include... Fort Collins, Wellington, Bellvue, Teds Place, Laporte, Waverly and Owl Canyon.
* WHAT...Flooding caused by excessive rainfall continues. * WHERE...Central Larimer County in north central Colorado. This includes the Cameron Peak Miller Fork burn scar area... * WHEN...Until 1215 AM MDT. * IMPACTS...Debris flows causing minor flooding. * ADDITIONAL DETAILS... - At 1055 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 0.5 and 1 inch of rain has fallen. - Some locations that will experience flooding include... Glen Haven.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...Central Larimer County in north central Colorado. This includes the Cameron Peak Miller Fork burn scar area... * WHEN...Until 1215 AM MDT. * IMPACTS...Debris flows causing minor flooding. * ADDITIONAL DETAILS... - At 910 PM MDT, Doppler radar indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Up to 0.5 inches of rain have fallen. - Additional rainfall amounts of 0.5 to 1 inch are expected over the area. This additional rain will result in minor flooding. - Some locations that will experience flooding include... Glen Haven.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...Northeastern Larimer County in north central Colorado... * WHEN...Until 1030 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. * ADDITIONAL DETAILS... - At 829 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Between 0.5 and 1.5 inches of rain have fallen. - Some locations that will experience flooding include... Virginia Dale and Red Feather Lakes.
* WHAT...Flooding caused by excessive rainfall is expected. * WHERE...Central Larimer County in north central Colorado... * WHEN...Until 915 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. * ADDITIONAL DETAILS... - At 721 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. Minor flooding is ongoing or expected to begin shortly in the advisory area. Up to 1 inch of rain has fallen. - Some locations that will experience flooding include... Kinikinik.
* WHAT...Small stream flooding caused by excessive rainfall continues. * WHERE...West Central Larimer County in north central Colorado... * WHEN...Until 915 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. * ADDITIONAL DETAILS... - At 724 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. This may cause small stream flooding. Between 0.5 and 1.5 inches of rain have fallen. - This includes the following streams and drainages... Rawah Creek, Sheep Creek, North Fork Rawah Creek, Camp Creek, Nunn Creek, Laramie River, Joe Wright Creek, Deadman Creek, Two and One Half Creek, Brinker Creek and North Fork West Branch Laramie River. - Some locations that will experience flooding include... Mainly rural areas of West Central Larimer County.
SVRBOU The National Weather Service in Denver has issued a * Severe Thunderstorm Warning for... Northeastern Grand County in north central Colorado... East Central Jackson County in north central Colorado... West Central Larimer County in north central Colorado... * Until 645 PM MDT. * At 622 PM MDT, a severe thunderstorm was located 6 miles north of Cameron Pass, moving northeast at 25 mph. HAZARD...Quarter size hail. SOURCE...Radar indicated. IMPACT...Damage to vehicles is expected. * Locations impacted include... Cameron Pass.
* WHAT...Small stream flooding caused by excessive rainfall is expected. * WHERE...North Central Park County in central Colorado... * WHEN...Until 900 PM MDT. * IMPACTS...Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 601 PM MDT, Doppler radar indicated heavy rain due to thunderstorms. This may cause small stream flooding. Between 0.5 and 1.5 inches of rain have fallen. - Additional rainfall amounts up to 0.5 inches are expected over the area. This additional rain will result in minor flooding. - Some locations that will experience flooding include... Jefferson, Kenosha Pass and Tarryall Reservoir.
At 538 PM MDT, Doppler radar was tracking a strong thunderstorm 8 miles west of Grand Lake, moving north at 10 mph. HAZARD...Wind gusts up to 40 mph and nickel size hail. SOURCE...Radar indicated. IMPACT...Gusty winds could knock down tree limbs and blow around unsecured objects. Minor damage to outdoor objects is possible. Locations impacted include... Mainly rural areas of Southeastern Jackson, Northeastern Grand and South Central Larimer Counties.
The Colorado Department of Public Health and Environment has issued the following... WHAT...Ozone Action Day Alert. WHERE...Douglas, Jefferson, Denver, western Arapahoe, western Adams, Broomfield, Boulder, Larimer, and Weld Counties WHEN...400 PM Tuesday July 21 to 400 PM Wednesday July 22 IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Hot and sunny weather with limited chances for afternoon storms will allow ozone concentrations to reach the Unhealthy for Sensitive Groups category on Tuesday and Wednesday. On Tuesday elevated ozone is possible in the Denver Metro area, Fort Collins, Greeley, and surrounding areas. On Wednesday the highest ozone is expected to be confined to locations within the Denver Metro area. For Colorado air quality conditions, forecasts, and advisories, visit: https://www.colorado.gov/airquality/colorado_summary.aspx If possible, please help us reduce ozone pollution by limiting driving gas and diesel-powered vehicles until at least 4 p.m. Wednesday, July 22, 2026. Colorado is also addressing ozone pollution through state policies. For more information about health impacts and how ozone pollution forms in Colorado, visit: https://cdphe.colorado.gov/ozone- pollution-and-your-health HEALTH INFORMATION...Increasing likelihood of respiratory symptoms and breathing discomfort in active children and adults and people with lung disease, such as asthma. Active children and adults, and people with lung disease, such as asthma, should reduce prolonged or heavy outdoor exertion.
* WHAT...Small stream flooding caused by excessive rainfall is expected. * WHERE...West Central Larimer County in north central Colorado... * WHEN...Until 800 PM MDT. * IMPACTS...Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 453 PM MDT, Doppler radar indicated heavy rain due to thunderstorms. This may cause small stream flooding. Between 0.5 and 1 inch of rain has fallen. - This includes the following streams and drainages... Rawah Creek, Sheep Creek, North Fork Rawah Creek, Camp Creek, Nunn Creek, Laramie River, Joe Wright Creek, Deadman Creek, Two and One Half Creek, Brinker Creek and North Fork West Branch Laramie River. Additional rainfall amounts of 0.5 to 1 inch are expected over the area. This additional rain will result in minor flooding. - Some locations that will experience flooding include... Mainly rural areas of West Central Larimer County.
At 320 PM MDT, Doppler radar was tracking a strong thunderstorm near Grant, moving northwest at 20 mph. HAZARD...Wind gusts up to 40 mph and nickel size hail. SOURCE...Radar indicated. IMPACT...Gusty winds could knock down tree limbs and blow around unsecured objects. Minor damage to outdoor objects is possible. Locations impacted include... Santa Maria.
The Colorado Department of Public Health and Environment has issued the following... WHAT...Ozone Action Day Alert. WHERE...Douglas, Jefferson, Denver, western Arapahoe, western Adams, Broomfield, Boulder, Larimer, and Weld Counties WHEN...400 PM Monday July 20 to 400 PM Tuesday July 21 IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Hot and stagnant weather conditions will result in ozone concentrations reaching the Unhealthy for Sensitive Groups category both Monday and Tuesday during the afternoon and evening hours. For Colorado air quality conditions, forecasts, and advisories, visit: https://www.colorado.gov/airquality/colorado_summary.aspx If possible, please help us reduce ozone pollution by limiting driving gas and diesel-powered vehicles until at least 4 p.m. Tuesday, July 21, 2026. Colorado is also addressing ozone pollution through state policies. For more information about health impacts and how ozone pollution forms in Colorado, visit: https://cdphe.colorado.gov/ozone- pollution-and-your-health HEALTH INFORMATION...Increasing likelihood of respiratory symptoms and breathing discomfort in active children and adults and people with lung disease, such as asthma. Active children and adults, and people with lung disease, such as asthma, should reduce prolonged or heavy outdoor exertion.
* WHAT...Small stream flooding caused by excessive rainfall continues. * WHERE...Northwestern Clear Creek County in central Colorado... Central Summit County in central Colorado... South Central Grand County in north central Colorado... * WHEN...Until 730 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 605 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. This may cause small stream flooding. Between 1 and 2 inches of rain have fallen. - Some locations that will experience flooding include... Silverthorne, Berthoud Falls and Berthoud Pass.
The Flood Advisory will expire at 430 PM MDT this afternoon for a portion of north central Colorado, including areas in the Cameron Peak burn scar. The heavy rain has ended. Small stream flooding is no longer expected to pose a threat. Please continue to heed any remaining closures.
* WHAT...Small stream flooding caused by excessive rainfall is expected. * WHERE...Northwestern Clear Creek County in central Colorado... Central Summit County in central Colorado... South Central Grand County in north central Colorado... * WHEN...Until 730 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 425 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. This may cause small stream flooding. Between 1 and 2 inches of rain have fallen. - Some locations that will experience flooding include... Silverthorne, Berthoud Falls and Berthoud Pass.
The Colorado Department of Public Health and Environment has issued the following... WHAT...Ozone Action Day Alert. WHERE...Douglas, Jefferson, Denver, western Arapahoe, western Adams, Broomfield, Boulder, Larimer, and Weld Counties WHEN...400 PM Monday July 20 to 400 PM Tuesday July 21 IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Hot and stagnant weather conditions will result in ozone concentrations reaching the Unhealthy for Sensitive Groups category both Monday and Tuesday during the afternoon and evening hours. For Colorado air quality conditions, forecasts, and advisories, visit: https://www.colorado.gov/airquality/colorado_summary.aspx If possible, please help us reduce ozone pollution by limiting driving gas and diesel-powered vehicles until at least 4 p.m. Tuesday, July 21, 2026. Colorado is also addressing ozone pollution through state policies. For more information about health impacts and how ozone pollution forms in Colorado, visit: https://cdphe.colorado.gov/ozone- pollution-and-your-health HEALTH INFORMATION...Increasing likelihood of respiratory symptoms and breathing discomfort in active children and adults and people with lung disease, such as asthma. Active children and adults, and people with lung disease, such as asthma, should reduce prolonged or heavy outdoor exertion.
* WHAT...Small stream flooding caused by excessive rainfall continues. * WHERE...Eastern Grand County in north central Colorado... West Central Boulder County in northeastern Colorado... * WHEN...Until 545 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 408 PM MDT, Doppler radar and automated rain gauges indicated heavy rain due to thunderstorms. This may cause small stream flooding. Between 1.5 and 2 inches of rain have fallen. - Some locations that will experience flooding include... Granby, Fraser, Winter Park, Grand Lake, Elkdale and Tabernash.
* WHAT...Small stream flooding caused by excessive rainfall continues. * WHERE...Southern Larimer County in north central Colorado within the upper Buckhorn Basin in the Cameron Peak burn area... * WHEN...Until 430 PM MDT. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 303 PM MDT, Doppler radar indicated heavy rain due to thunderstorms. This may cause small stream flooding. Between 0.5 and 1 inch of rain has fallen. Rainfall has ended, but small streams may remain elevated for the next hour or two. - Some locations that will experience flooding include... Buckhorn Creek, Cascade Creek.
* WHAT...High Temperatures 99 to 103. * WHERE...Fort Collins, Boulder, Denver metro, and Greeley. * WHEN...Until 9 PM MDT this evening. * IMPACTS...Hot temperatures may cause heat illnesses.
* WHAT...Small stream flooding caused by excessive rainfall is expected. * WHERE...Eastern Grand County in north central Colorado... West Central Boulder County in northeastern Colorado... * WHEN...Until 545 PM MDT. * IMPACTS...Rises in small streams and normally dry creeks. * ADDITIONAL DETAILS... - At 251 PM MDT, Doppler radar indicated heavy rain due to thunderstorms. This may cause small stream flooding. Between 1 and 1.5 inches of rain have fallen. - Some locations that will experience flooding include... Granby, Fraser, Winter Park, Grand Lake, Elkdale and Tabernash.