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June 12 to June 18: This week in Denver weather history

Thursday, June 16th, 2016 4:06am MST
This Week In Denver Weather History

June 12 to June 18: This week in Denver weather history

The first half of June is when Colorado’s severe weather season really kicks into high gear and our look back at this week in Denver weather history reflects that. Numerous flooding, hail, and tornadic events punctuate just how dangerous and damaging our weather can be this time of year.

From the National Weather Service:


In 1999…damage from several hailstorms in and near metro Denver totaled 35 million dollars. About 17.5 million dollars was from automobile claims with another 17.5 million in homeowner claims. The areas hardest hit by the storms included Castle Rock…Commerce City…Evergreen… And Golden.


In 1901…south winds were sustained to 45 mph with an extreme velocity to 47 mph.

In 1917…northwest winds were sustained to 40 mph with gusts to 45 mph.

In 1927…flooding on Little Dry Creek in Englewood resulted in two deaths.

In 1947…a trace of snow fell over downtown Denver during the early morning. This was the latest last snow of the season (trace or more). This also marked the end of the longest snow season…264 days…from the first snow…a trace…on September 22…1946. High temperature of 43 degrees was a record low maximum for the date. Minimum temperature of 33 degrees was a record low for the date.

In 1971…a funnel cloud sighted over Arvada possibly touched down at the base of the foothills. The public reported 3/4 inch to 1 inch diameter hail over the city of Denver.

In 1974…strong thunderstorm winds caused damage to power lines in metro Denver. Northwest winds gusted to 45 mph at Stapleton International Airport.

In 1975…a thunderstorm wind gust to 56 mph was recorded at Stapleton International Airport.

In 1982…three small tornadoes were sighted near Bennett. One of the twisters caused minor crop and road damage along its path. A brief tornado was sighted by national weather service observers at Stapleton International Airport.

In 1983…3/4 inch hail fell in Boulder. Golf ball to 3/4 inch size hail fell in Arvada…denting cars and house roofs. Over a thousand hail damage insurance claims were filed from the area. Golf ball size hail also fell in Northglenn and Bennett…1 to 2 inch hail in Thornton…2 1/2 inch hail in northeast of Denver. A tornado was sighted 10 miles northeast of Stapleton International Airport; it was only on the ground for 1 to 2 minutes.

In 1984…large hail pelted many parts of southern metro Denver. Fifteen aircraft were damaged by golf ball size hail at Centennial airport. Golf ball size hail was reported in south Denver…and 3/4 inch hail was measured in southeast Aurora.

In 1987…a small weak tornado touched down for about 3 minutes near the intersection of I-70 and Colorado Blvd in northeast Denver. No damage was recorded. A microburst wind gust to 53 mph was recorded at Stapleton International Airport.

In 1991…in the city of Denver…lightning struck a tree under which seven people were picnicking. One person was critically injured. The others received only minor injuries.

In 1992…golf ball size hail fell in Evergreen.

In 1994…microburst winds gusting to 53 mph kicked up some blowing dust at Stapleton International Airport.

In 1996…lightning struck a house in Parker…which sparked a fire. The bolt was strong enough to blow nails out of the drywall in one room. About 85 percent of the house was damaged. No dollar estimate of the damage was available. Lightning also struck a power line in Boulder…which left 250 customers without electricity for a short time.

In 1997…a tornado touched down near Parker…damaging some construction equipment. Hail to 2 inches in diameter was measured in Henderson. One inch diameter hail fell in the city of Denver with 3/4 inch hail measured in Lakewood.

In 1999…hail as large as 1 1/2 inches in diameter struck Hudson. A funnel cloud was sighted by ramp personnel to the east of Denver International Airport.

In 2003…lightning blew a hole in the roof of a house in Highlands Ranch. The bolt knocked several holes in the bedroom ceiling and damaged the home’s electrical system.

In 2004…lightning struck a home in Louisville…but caused only minor damage.

In 2006…a strong microburst wind gust…estimated at 69 mph… Ripped the roof off a horse barn near the intersection of Havana Street and Smith Road in Denver. A 13 year old girl was injured…when she was thrown from a horse inside the barn at the time the roof was being torn off. A thunderstorm produced a microburst wind gust to 54 mph and a trace of rainfall at Denver International Airport. A severe thunderstorm produced hail to 0.75 inch near Watkins.


In 2000…two large wildfires developed in the Front Range foothills as careless campers and very dry conditions proved to be a dangerous combination. Strong winds gusting in excess of 60 mph on the 13th fanned the flames… Spreading both wildfires out of control. Winds gusted to 78 mph atop Niwot Ridge near the Continental Divide west of Boulder. The Hi Meadows wildfire…about 35 miles southwest of Denver…consumed nearly 11 thousand acres and 80 structures…mostly high priced homes. The Bobcat wildfire…located about 12 miles southwest of Fort Collins… Consumed nearly 11 thousand acres and 22 structures. Late on the 16th…a strong cold front moved south over the great plains into northeastern Colorado. Low level upslope conditions developed in the wake of the front…producing 2 to 4 inches of snowfall overnight at elevations above 8 thousand feet. Firefighters were able to contain both fires shortly thereafter.


In 1956…a microburst caused a brief wind gust to 59 mph at Stapleton Airport.

In 1957…an unconfirmed tornado appeared to touch the ground in the vicinity of Franktown. No damage was reported from the twister.

In 1968…a violent gust of wind…possibly associated with a thunderstorm…caused 75 hundred dollars damage in Boulder.

In 1973…hail…1/2 to 3/4 inch in diameter…fell over Lakewood. Flash flooding occurred in west Denver from the same storm.

In 1974…a thunderstorm wind gust to 64 mph was recorded at Stapleton International Airport.

In 1977…hail the size of table tennis balls…1 1/2 inches in diameter…was reported in Boulder.

In 1981…large hail to golf ball size fell in Denver… Northglenn…and Brighton. Hail as large as baseballs was reported in federal heights.

In 1984…one of the worst hailstorms ever experienced in metro Denver struck the northwestern suburbs of Arvada…Wheat Ridge…and Lakewood…but large hail also fell in Golden… Southeast Denver…and Aurora. Homes and other buildings sustained around 200 million dollars in damage. Thousands of cars were battered by giant hailstones…and total damage to vehicles was estimated at 150 million dollars. In some areas…golf ball size hail fell continuously for 30 to 40 minutes. Some places were pelted with a few stones as large as grapefruits! Roofs on thousands of structures were severely damaged. Uncounted car windshields were broken; two-thirds of Arvada’s police cars were rendered inoperable. Torrential rains…with as much as 4.75 inches in Lakewood clogged drains and caused widespread damage from flooding. In some places hail was washed into drifts several feet deep. About 20 people were injured by the giant hailstones. One couple was hospitalized. A woman drowned when she was trapped under a trailer by high water. Only pea size hail fell at Stapleton International Airport.

In 1988…2 inch hail fell in Parker. Soft hail 1 inch in diameter fell at the mouth of turkey creek canyon 5 miles southeast of Morrison. Hail between 1 inch and 1 3/4 inches fell at both Bennett and Strasburg. A tornado touched down briefly at Strasburg. A brief funnel cloud was sighted by national weather service observers 15 miles southwest of Stapleton International Airport.

In 1991…a Boulder man was injured when struck by lightning while in a tent. He received only minor burns.

In 1997…lightning struck a home in Denver. The extent of the damage was unknown. A home in Littleton was also struck. The house caught fire…but the extent of the damage was not known.

In 1998…a strong mountain wave produced a brief period of high winds along the Front Range. A small building atop squaw pass west of Denver was blown down. Tree limbs were downed across metro Denver. Peak wind gusts included: 80 mph on Squaw Pass…69 mph at Jefferson County Airport near Broomfield…and 60 mph in Westminster and at the National Center for Atmospheric Research in Boulder. West-northwest winds gusted to 51 mph at Denver International Airport.

In 2001…high winds developed briefly in Boulder County. A peak wind gust to 76 mph was recorded at the National Center for Atmospheric Research atop the mesa in Boulder. A wind gust to 72 mph was recorded at southern hills middle school in Boulder. Lightning started a small fire…which damaged the roof of a house in Greenwood Village.

In 2009…severe thunderstorms produced hail up to one inch in diameter near Arvada and byers…as well as 7 miles north-northwest of Front Range airport near watkins.


In 2006…the high temperature of 99 degrees on the 13th equaled the record maximum temperature for the date first set in 1994. The high temperature of 102 degrees on the 14th was a new record maximum temperature for the date.


In 1877…an evening thunderstorm produced lightning which struck several houses and killed a cow in the bottom land of the South Platte River

In 1886…hail as large as 3/4 inch in diameter fell in the city. Precipitation was only 0.10 inch.

In 1887…south winds were sustained to 41 mph.

In 1900…a thunderstorm produced northwest winds to 51 mph with gusts to 61 mph…but only a trace of rain.

In 1923…a severe thunderstorm pelted the city with hail. The stones ranged in diameter from 0.2 to 0.8 inch. Gardens and greenhouses suffered considerable damage. Rainfall was only 0.14 inch downtown.

In 1960…one workman was killed and 4 others injured in Lakewood when a partly built apartment building collapsed in strong winds. Microburst wind gusts to 54 mph caused some blowing dust at Stapleton Airport.

In 1967…tornadoes touched down briefly 3 miles west of Franktown and 4 miles northeast of Parker. No damage was reported. Numerous funnel clouds were reported over south metro Denver…one 5 miles south of Denver…one 2 to 3 miles north of Castle Rock…and two near Littleton.

In 1968…a microburst wind gust to 52 mph was recorded at Stapleton International Airport.

In 1972…1 3/4 inch hail was reported in Wheat Ridge.

In 1976…high winds…unusually strong for this late in the season…raked metro Denver. Wind gusts estimated to 100 mph tore 24 boats from their moorings and damaged a total of 47 boats at Boulder reservoir. Wind gusts to 82 mph were recorded in Boulder. The strong winds toppled the wind mast at a radio station in Boulder. An automobile was smashed by a fallen tree in Boulder. Other damage in Boulder was minor…but power outages occurred when tree limbs fell on power lines. At Jefferson County Airport near Broomfield…wind gusts to 78 mph were recorded with 87 mph gusts clocked at Rocky Flats nuclear plant south of Boulder. Wind gusts to 66 mph were observed in Littleton… And northwest winds gusted to 46 mph at Stapleton International Airport. The strong winds collapsed a barn near Arvada. Several horses received minor injuries. Thirty trees were uprooted or broken in Denver. Four major power outages occurred from west Denver and Lakewood to the foothills.

In 1982…the worst hailstorm in 17 years struck Commerce City. The storm left 4 to 8 inches of hail on the ground. A few of the stones were as large as golf balls. Many vehicles were dented…and some windshields were shattered. Roofs of homes were damaged. Total damage was estimated at over one million dollars. Hail to 1 inch in diameter also fell in Littleton. Only 1/4 inch hail was measured at Stapleton International Airport.

In 1988…lightning ripped a small hole in the roof of a home in the southern part of Boulder. There were some power outages in the area.

In 1992…an off duty national weather service employee reported hail to 1 inch diameter in Westminster.

In 1997…one inch diameter hail fell in Bennett…and 3/4 inch hail was measured in Littleton.

In 1999…hail as large as 1 1/2 inches in diameter hit Aurora. Lightning sparked two small fires at separate residences near the Hiwan Country Club in Evergreen.

In 2004…lightning sparked two small fires near Jamestown. One was in Geer Canyon and the other 7.5 miles up Sunshine Canyon. Both were quickly contained and caused no damage to structures in the area.

In 2009…a complex of severe thunderstorm produced large hail damaging thunderstorm and funnel clouds across parts of the urban corridor. The line formed along a boundary over the western suburbs of Denver then moved east. The boundary produced at least one well defined funnel cloud that could be observed by stadium full of baseball fans at Coors Field. Large hail…up to 1 3/4 inches in diameter…was reported in Arvada…Broomfield…Denver…Federal Heights and Northglenn. In addition…the storm produced peak wind gusts from 60 to 74 mph. At Denver International Airport…a peak wind gust to 58 mph was observed from the west-northwest.

In 2014…severe thunderstorms broke out across the Urban corridor. Large hail…ranging in size from 1 to 2 inches in diameter…was observed. The area extended from around Englewood to Aurora and included: Brookridge…Cherry Knolls… Greenwood Village and south Denver. As many as 212 thousand residences were potentially impacted by the storms. The hail shattered windshields and damaged vehicles.

» Click here to read the rest of June 12 to June 18: This week in Denver weather history

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Wednesday offers lots of sun, rising temperatures

Wednesday, June 15th, 2016 5:17am MST

Today’s weather forecast for Thornton is really quite short and simple. With high pressure dominating the region, conditions will be stable and unseasonably warm.

Sunny skies will be above throughout the day with just a few clouds here and there but none that will obscure the view. Winds will be calm during the daytime hours then become a bit breezy in the late afternoon and evening.

Temperatures will be climbing to a high of around 92 degrees, 10 degrees above normal. More of the same, hot weather will be in store for us through the week.

Keep an eye on the current mercury reading here.

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Lots of sun, mild temperatures for Thornton’s Tuesday

Tuesday, June 14th, 2016 5:10am MST

Gone are the thunderstorms of the past few days and in its place is a warming, stable atmosphere. While the lack of storms might be nice to some, the mercury is going to be climbing in the coming days leading to an extended period of well above normal temperatures.

For today look for sunny skies to be above with only a cloud here and there. Winds will be light and conditions calm as we head for a high temperature in the mid-80s, just a bit above the average of 82 degrees.

Looking ahead, the balance of the week is going to just get warmer. Low to mid-90s will be seen Wednesday followed by highs in the mid-90s through Saturday.

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Monday starts the workweek with a significant severe weather threat

Monday, June 13th, 2016 5:05am MST

Following on our hot and relatively calm weekend, things take a more serious turn on Monday. A healthy dose of moisture coupled with instability and shear are going to lead to an afternoon with the potential for large hail, damaging wind and possibly some tornadoes.

We start the day with mostly to partly sunny skies. By late morning a few more clouds will be seen. Temperatures will be climbing to a high right near the average for today’s date of 82 degrees.

A few thunderstorms could be seen as early as mid to late morning but the real threat begins this afternoon, particularly between about 2:00pm and 5:00pm as convection gets started in earnest.

With little to inhibit their development, these thunderstorms are going to find an atmosphere primed to allow quick and robust development. Large hail and damaging wind will be the biggest threats but we can’t rule out the potential for tornadoes as well.

Residents need to be very cautious today and pay close attention to the weather! Be sure to keep an eye on our Severe Weather Briefing Page for the latest.

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Climate models overstating case for man-made global warming, study suggests

Friday, June 10th, 2016 10:21am MST

The Earth

Climate models overstating case for man-made global warming, study suggests

Whenever climate models overestimate temperatures linked to rising carbon dioxide levels in the atmosphere, scientists have pointed to a convenient fall guy: aerosols, which cool the planet and act as a counterweight to global warming. But what if the cooling influence of aerosols isn’t as powerful as believed? Preliminary findings from a major study by the… » Click here to read the rest of Climate models overstating case for man-made global warming, study suggests

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Hot temperatures, some thunderstorms for Thornton’s weekend

Friday, June 10th, 2016 4:33am MST

We fell just shy of getting our first 90 degree day of the year yesterday but we once again have a good chance of hitting the mark today and tomorrow. Sunday cools things down some.

For today look for sunny to mostly sunny skies during the daytime hours. Conditions will be dry and calm as we head toward a high temperature around 93 degrees. This evening brings just a slight chance for thunderstorms, much like we saw late yesterday.

Saturday offers a few more clouds but not relief from the heat. A high mercury reading of 93 degrees will again be very possible. Chances for afternoon and evening thunderstorms increase.

We close out the weekend on Sunday with temperatures cooling some and getting at least a bit closer to normal. Look for highs in the mid-80s. We do see a good bit of moisture and instability for the period so showers and thunderstorms will be possible, particularly in the afternoon.

Have a great weekend and stay cool!

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Thornton’s 2015 – 2016 seasonal snowfall totals end far above average

Thursday, June 9th, 2016 11:05am MST
Thornton, Colorado monthly and seasonal snowfall totals from the 2006 / 2007 season to the the 2015 / 2016 season. (ThorntonWeather.com)

Thornton, Colorado monthly and seasonal snowfall totals from the 2006 / 2007 season to the the 2015 / 2016 season. Click for larger view. (ThorntonWeather.com)

To say we had a lot of snow this past season would be a bit of an understatement.  Our total came in at more than 2 feet higher than historical average for Thornton and Denver.

In all, Thornton received 85.7 inches of snowfall for the 2015 / 2016 season.  That total eclipses the 10-year Thornton average of 58.0 inches and Denver’s official 30-year average (1981 – 2010) of 55.3 inches.

The measurement is also Thornton’s highest snowfall total of the past 10 years since ThorntonWeather.com came into existence.  The next highest seasonal total is the 72.9 inches received during the 2006 / 2007 season.

Thornton saw five months with above normal snowfall.  Most notable was November which received nearly 10 inches more than normal and March with 18.9 inches more than average.

Denver’s official seasonal total was well above normal as well.  Out at Denver International Airport where the measurements are taken, The National Weather Service reported 72.8 inches.

It is likely if the Mile High City’s measurements were still done at a location in the city, the total would have been a good bit higher.

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Thornton’s Thursday slated to bring first 90 degree day of the year

Thursday, June 9th, 2016 5:33am MST

With high pressure building, a lack of moisture and clear skies, we are set to see very summer-like temperatures today lasting into the weekend.

Sunny skies start things off and while there may be a few clouds here and there, bright sun will be the general rule for the day today. Winds will be calm and we will be staying dry.

Temperatures are going to be climbing to a high of around 93 degrees, our first 90 degree reading of the season.

We’ll be following that up with two more similarly hot days Friday and Saturday before cooling down slightly on Sunday. Keep an eye on the rising mercury with our live gauges here.

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Very mild temps, PM storms again in Wednesday’s forecast

Wednesday, June 8th, 2016 5:05am MST

Not much change in today’s weather forecast for Thornton. Biggest difference between today and the previous two is that we will see warmer temperatures and thunderstorms will be largely high-based and thus bring mostly wind.

We start out the day with mostly sunny skies and those will be with us through the morning into the first part of the afternoon. Temperatures will be climbing steadily toward a high of around 88 degrees.

Thunderstorms will again develop with our best chance for activity coming in the late afternoon. There is less low level moisture today which means the storms will be a bit higher with wind being the biggest threat although we may see some rain from them as well.

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Tuesday brings a repeat of yesterday’s mild temps, thunderstorms

Tuesday, June 7th, 2016 5:01am MST

Very little change in today’s weather forecast for Thornton versus what we saw yesterday. Temperatures will once again be a few degrees above normal and the afternoon looks to offer up some thunderstorm activity.

We start out sunny to mostly sunny with clouds slowly increasing through the morning and early afternoon. Temperatures will also be steadily increasing as the day progresses, topping out around 84 degrees.

Scattered thunderstorms are expected to initially develop in the mountains and foothills then move onto lower terrain. Best chances for activity in our area will come from about 3:00pm to 8:00pm.

We will then see most of the cloud cover move off overnight and an overnight low in the mid-50s.

Keep an eye on current conditions with our live weather gauges here.

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