Colorado weather is certainly varied and this week’s look back at weather history proves that. We have seen everything from deadly lightning, hail and severe winds to even snow during the second week of September.  Most notably however were the devastating – and deadly – floods of 2013.
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In 1978…the temperature reached 90 degrees or more on seven consecutive days with the highest temperature…94 degrees… Recorded on both the 4th and 6th.
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In 1909…rainfall for the 4 days accumulated to 3.97 inches in Boulder…while in Denver rainfall totaled 2.45 inches on the 4th…5th…and 6th.
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In 1988…layers of smoke aloft from large forest fires in Yellowstone National Park completely obliterated the sun at times. At Stapleton International Airport…surface visibility was reduced at times to 5 and 6 miles in smoke.
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In 2010…the Fourmile Canyon wildfire…northwest of Boulder… Broke out on the morning of the 5th. It originated from an unattended fire pit at a local residence. The wildfire quickly consumed 5 1/2 square miles or 3500 acres the first day…and forced the evacuation of over three thousand residents. Erratic 45-mph gusts sent the fire in two directions at times. Very dry weather conditions preceded the fire. The combination of strong winds…low relative humidities and dry fuels allowed the wildfire spread rapidly through the steep…heavily forested terrain. The flames were reportedly 20 to 50 feet in length. Towns within the burn area included Salina…Wallstreet and Gold Hill. The dry conditions coupled with gusty winds ranging from 45 to 64 mph persisted for several more days. Fire managers used as many as 700 firefighters and support personnel from 35 agencies and seven air tankers to battle the wildfire. A total of 6181 square acres or approximately 10 square miles were burned. The Fourmile Canyon wildfire was the most destructive fire in Colorado history in terms of the damage to personal property. It destroyed 171 homes with an estimated cost of 217 million dollars.
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In 1940…a thunderstorm pelted the city with small hail. The storm produced some lightning damage. One woman was stunned by a bolt which struck near her. Heavy rain from the storm raised the level of Cherry Creek by more than 3 feet during the height of the storm. Rainfall downtown was only 0.26 inch.
In 1988…strong winds blew down two houses that were under construction in Castle Rock. Northwest winds gusted to 44 mph at Stapleton International Airport.
In 1993…a man was struck and killed by lightning while standing outside his home in unincorporated Arapahoe County 11 miles south of Denver. Lightning also struck a cabin in Marshdale…20 miles southwest of Denver…which started a fire and damaged one room and a portion of the roof.
In 1995…hail as large as 3/4 inch in diameter fell in Coal Creek Canyon in northern Jefferson County.
In 2001…a thunderstorm dropped 3/4 inch diameter hail in Aurora near Cherry Creek.
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In 1875…the creeks were running dangerously high during the night from heavy rains in the mountains.
In 1885…a thunderstorm produced very white hail of irregular shape and about the size of beans. Precipitation was only 0.10 inch.
In 1971…a vigorous cold front accompanied by a thunderstorm produced wind gusts to 48 mph at Stapleton International Airport and much upslope cloudiness and light rain across metro Denver.
In 1989…widespread thunderstorms produced lightning strikes that knocked out power to about 13 thousand homes in Boulder County. In a rugged area stripped of vegetation by a forest fire earlier in July…heavy rain triggered mud slides that destroyed one home and severely damaged another in Boulder canyon 10 miles west of Boulder. In one home…the mud caved in an exterior wall and poured into the residence only seconds after 2 people had evacuated the premises. Rainfall totaled 1 to 3 inches. Hail 1 3/4 inches in diameter fell in Nederland…Idaho Springs…and Golden Gate Canyon. Hail 1 inch in diameter was measured 10 miles north of Golden.
In 1993…thunderstorm winds toppled an overhead sign onto the intersection of I-70 and I-25 in Denver…causing considerable damage to 4 vehicles. The winds also caused a police car to be blown off the road northeast of Denver. Thunderstorm winds gusting to 66 mph damaged the siding of a residence southeast of Brighton. A thunderstorm wind gust to 53 mph was recorded at Stapleton International Airport. Hail to 7/8 inch in diameter fell at Kittredge in the foothills of Jefferson County.
In 1994…lightning severely damaged a public television transmitter atop squaw mountain west of Denver.
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In 1884…a windstorm from mid-afternoon until the early morning hours of the 8th produced south winds sustained to 48 mph. The strong winds toppled several trees in the city.
In 1892…there was a trace of rainfall each day. This together with a trace of rain on both the 2nd and 3rd was the only rainfall of the month…making the month the driest on record. The record was equaled in 1944.
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In 1886…the last thunderstorm of the season pelted the city with hail the size of beans and dropped 0.81 inch of precipitation.
In 1962…the earliest first freeze of the season occurred. The temperature dipped to a low of 31 degrees.
In 1973…hail up to 1 1/2 inches in diameter fell northeast of Boulder. A tornado was reported by a pilot east of Parker. No damage was reported.
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In 1933…heavy rain in the foothills over the clear creek and Golden gate canyon watersheds caused flooding in Golden and damaged the roadway in Golden gate canyon… Which resulted in its closure.
In 1969…a funnel cloud was sighted in southeast Denver. There was also considerable thunderstorm activity and local heavy rain across metro Denver. Rainfall totaled 1.30 inches at Stapleton International Airport where small hail also fell.
In 1973…hail from 3/4 inch to 1 3/4 inches in diameter fell in Westminster and south of Broomfield.
In 2009…a man was critically injured when he was struck by lightning while riding his bicycle. He was nearing a paramedic van when he was hit. His heart stopped but paramedics quickly responded and were able to resuscitate him.
In 2011…a man was struck by lightning at the Adams County Fairgrounds. He was leaning against a tree while watching a cross country meet when the tree was hit. The lightning traveled down the tree and up through the ground…using him as a conductor. The victim received second and third degree burns.
Continue reading September 6 to September 12: This week in Denver weather history →
Following an August that was unseasonably warm and dry, we find ourselves heading into September hoping for relief. Â The month can bring plenty of rain and even our first snow of the season but more often than not, it is one of the most pleasant along the Colorado Front Range.