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Public Information Statement
National Weather Service Denver/Boulder CO
645 PM MDT SAT JUN 15 2024

...This week in metro Denver weather history...

12-17 In 2000...two large wildfires developed in the Front Range
        foothills on the 12th and continued through the 17th...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 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.
15-16 In 1963...heavy rain and hail ravaged metro Denver.  In
        southeast Denver...heavy rain flooded homes and streets.
        Hail to a depth of 4 inches on the ground stripped trees
        and plants and drifted to depths of 3 to 4 feet in some
        areas.  Flood waters on the Valley Highway were 19 feet
        deep in places...trapping many cars.  Many creeks were
        running over their banks.  On the 15th...the main
        thunderstorm cell passed over south Denver...dumping as
        much as 4 inches of rain in 90 minutes.  Precipitation
        at Stapleton Airport totaled 0.91 inch on the 15th and
        1.31 inches on the 16th.  A funnel cloud was sighted
        briefly 4 miles to the south-southeast of Stapleton
        Airport on the 15th.  Damage from hail and flooding
        amounted to near a million dollars.
15-17 In 2021...the temperature in Denver reached 100 degrees for
        three consecutive days:  101...100...100 respectively.  Each
        established a new record high for the day.  It was also the
        earliest occurrence of such a streak. A record high minimum
        of 68 also occurred on the 17th.
16    In 1950...very heavy rain and hail storms in southwest Denver
        caused an estimated 750 thousand dollars in hail and flood
        damage.  Thunderstorms produced 2.06 inches of rain at
        Stapleton Airport with 2.23 inches of rain measured in
        downtown Denver.
      In 1965...a tornado...15 miles south-southeast of Denver...
        touched down and damaged two houses in northern Douglas
        County.  Three golfers at a country club and a women who
        lived north of Castle Rock were injured by falling
        structures.
      In 1983...a microburst wind gust to 54 mph was recorded at
        Stapleton International Airport.
      In 1984...a tornado touched down briefly in Parker.  No damage
        was reported.
      In 1986...lightning injured 5 people just north of the Denver
        city limits in Adams county.  The victims were members of
        a drum and bugle corps and were standing near a metal
        scaffold.  Heavy rain from the storm also caused street
        flooding in the metro area.
      In 1991...hail to golf ball size fell at Conifer.
      In 1992...a rare mid-June high wind event wrecked havoc
        over metro Denver when a Pacific cold front moved across
        the Rocky Mountains.  Strong winds at speeds of 40 to 50
        mph were common along the Front Range foothills.  Winds
        reaching 107 mph in the foothills west of Denver and 79 mph
        at Longmont...caused damage ranging from trees being toppled
        to large trucks being rolled over.  Strong winds estimated
        at 75 mph rolled a 35-foot truck carrying building supplies
        on U.S. Highway 36 north of Boulder.  The truck driver and
        a passenger as well as the driver of another car were
        slightly injured.  The winds downed power lines.  The
        gambling towns of Central City and Blackhawk were without
        power for a couple of hours.  West winds reached 43 mph at
        Stapleton International Airport.
      In 1996...a small tornado touched down in the foothills
        southwest of Boulder near Pinecliffe...knocking down
        50 to 100 large pine trees.  A house nearby sustained
        damage when shingles were ripped from the roof.  The tornado
        also picked up a 17-foot sailboat with attached trailer and
        carried it 25 feet into a nearby tree.  In addition...
        thunderstorm wind gusts to 46 mph were measured at Denver
        International Airport.
      In 2004...hail as large as 1 inch in diameter fell near Castle
        Rock.  Hail to 3/4 inch was measured near Bennett.
      In 2005...severe thunderstorms produced hail as large as 1 inch
        in diameter in Centennial.
      In 2011...severe thunderstorms produced and damaging across
         parts of metropolitan Denver. In Lakewood...a tree blew down
         and landed on at least five cars. At Centenniel Airport...a
         section of a roof on a hangar was ripped off the strong
         winds.  A peak wind gust of 46 mph was recorded at
         Centenniel Airport and Denver International Airport in
         the evening.
      In 2022...severe thunderstorms produced large hail across
         parts of Boulder and Weld counties. The hail ranged from
         1 to 1 1/2 inches at Allenspark...Ft. Lupton...Hudson and
         Lochbuie.
16-17 In 1965...on the afternoon and evening of the 16th...violent
        thunderstorms produced extremely heavy cloudbursts of rain
        over the Palmer Divide and sent a wall of water as high as
        20 feet down both branches of Plum Creek into the South
        Platte River and through metro Denver.  The heavy rainfall
        produced the most devastating flood in the history of
        Denver.  Rainfall totaled 14.0 inches in 3 hours at both
        Larkspur and Palmer Lake with 12.0 inches recorded in Castle
        Rock.  The flood waters caused extensive damage to roads and
        bridges in Larkspur...Castle Rock...and Sedalia...including
        washing out the I-25 bridge over East Plum Creek in Castle
        Rock.  The citizens of metro Denver received reports of the
        flooding to the south and had a few hours to initiate
        evacuation procedures along the South Platte River...greatly
        limiting the loss of life.  By evening...the flood reached
        Littleton where an heroic effort was made to save nearly
        150 horses at the Centennial Racetrack...which was
        completely inundated by the flood waters.  As the flood
        proceeded through the City of Denver...the river became more
        than 1/2 mile wide and destroyed all homes...trailer courts...
        and businesses in its path.  The waters contained debris
        ranging from refrigerators to old cars.  As many as 26
        bridges were damaged or destroyed...including the 6th Avenue
        freeway bridge across the South Platte.  Both Public Service
        Company power plants were shut down by the flood.  The King
        Soopers grocery chain bakery was inundated.  About midnight...
        the torrent crested at 25 feet above normal with flow
        exceeding 40 times normal and is the record flood on the
        South Platte and many of its tributaries.  The flood caused
        230 million dollars in damage and 8 deaths along the entire
        South Platte River basin.  The intense rain also caused
        flooding along Cherry Creek in Denver...on Toll Gate and Sand
        Creeks in east metro Denver...and on Kiowa and Bijou Creeks
        to the east of Denver.  The South Platte River flood closed
        nearly every major east-west highway into Denver...nearly
        isolating the city.  The flood caused heavy damage to state
        and county roads in the area.  Railroads were also hard hit
        with the main yards in lower downtown inundated.  Sewerage...
        water supply facilities...and irrigation works also received
        heavy flood damage.  The flood crest did not reach Nebraska
        until the 20th.
17    In 1915...northwest winds were sustained to 41 mph with an
        extreme velocity to 42 mph.
      In 1967...this was the 24th consecutive day with a trace
        or more of precipitation from May 25th.  Precipitation
        totaled 5.87 inches during the period...more than a
        third of the average yearly total.
      In 1975...hail more than 2 inches in diameter fell in
        eastern Aurora.
      In 1977...golf ball size hail was reported 3 miles east of
        Arapahoe County Airport...now Centennial Airport.  Heavy
        hail to 3/4 inch in diameter was reported in Littleton...
        Castle Rock...and Sedalia.
      In 1979...a man and a girl were struck and killed by lightning
        while walking in a park in northwest Denver.
      In 1987...3/4 inch hail fell near Boulder.
      In 1991...a microburst wind gust to 59 mph kicked up some
        blowing dust at Stapleton International Airport.
      In 1998...hail as large as 3/4 inch in diameter fell in
        Boulder.
      In 2003...lightning struck a feeder line...knocking out the
        electricity to about 3000 residents in Littleton.  A
        lightning strike caused minor damage to the roof and attic
        of a home in Lafayette.  Another lightning strike caused
        minor roof damage to a residence in Louisville.  Yet
        another lightning strike hit a home in Denver and caused
        a small attic fire.  Hail as large as 1 inch in diameter
        was measured near Centennial Airport and near Greenland.
      In 2009...hail up to 1 inch in diameter was measured near
        Longmont.
      In 2015...a severe thunderstorm produced hail up to 1 1/2
        inches in diameter near Arapahoe Park...and up to 1 inch
        in diameter near Parker.
17-18 In 1964...from the 17th to the 18th...high winds at speeds of
        50 to 60 mph with gusts as high as 75 mph caused damage to
        homes...power lines...and trees in Boulder.  Non-convective
        west winds gusting to 46 mph caused some blowing dust at
        Stapleton International Airport on the 17th.
18    In 1875...a windstorm produced sustained winds to 45 mph
        during the morning hours.  Numerous forest fires along
        the base of the mountains were visible from the city.
      In 1886...northwest winds sustained to 40 mph were the
        strongest of the month that year.
      In 1987...severe thunderstorms produced lightning...large hail...
        a tornado...heavy rain...and strong winds across metro Denver.
        Rainfall totaled 2.50 inches in an hour in Wheat Ridge...
        causing minor flooding.  I-25 was flooded in north-central
        Denver...snarling traffic.  Hail 7/8 inch in diameter fell in
        Louisville with 1 1/2 inch hail near Golden and 1 to 1 3/4
        inch hail in and near Castle Rock.  A tornado touched down
        briefly in Castle Rock.  No damage was reported.  Lightning
        started a small fire that burned half a cabin near
        Evergreen.
      In 1994...a funnel cloud was sighted over Aurora; hail to
        1 3/4 inch diameter fell near Brighton; and hail over an
        inch in diameter fell over Aurora...southeast Denver...
        Louisville...and Boulder.  Lightning struck a home in
        Henderson 9 miles north of Denver and knocked a hole in
        the roof...which caused the ceiling to collapse.  Hail to
        1 1/4 inch diameter was measured at Stapleton International
        Airport.
      In 2002...the Hayman Wildfire in the foothills to the southwest
        of Denver intensified...and the winds aloft carried the smoke
        plume directly over metro Denver...again creating a dense haze
        of smoke which blocked the sun.  Surface visibilities were
        again reduced to as low as 1 1/4 miles at Denver
        International Airport.
      In 2004...severe thunderstorms produced hail to 3/4 inch in
        diameter near Morrison...in Littleton...near Conifer...near
        Castle Rock...and in Aurora near Cherry Creek.
      In 2013...a landspout tornado touched down at DIA. The tornado
        sent 10 thousand travelers on the concourse...on planes and in
        the terminal scrambling to get into tornado shelters. The
        tornado formed just to the south of Runway 35R and then moved
        slowly northwest between Runway 35R and 35L...and moved to
        within one third of a mile of Concourses A and B before
        dissipating. The tornado moved extremely close if not over the
        ASOS (Automated Surface Observation System) and another low
        level wind shear sensor at DIA. The ASOS weather observing
        system reported a 97 mph wind gust...while the wind shear sensor
        reported a wind gust to 109 mph at the same time  indicative
        of an EF1 tornado. There was only minor damage noted to the
        equipment. Nine flights were diverted elsewhere during a
        tornado warning. Severe thunderstorms also produced large hail
        up to 1 inch in diameter in Adams and Weld Counties.
      In 2014...a severe thunderstorm produced large hail up to quarter
        size near Buckley Air Force Base.  At Denver International
        Airport...a peak wind gust to 55 mph was observed from the
        southwest...along with 0.37 inches of water.
      In 2015...a severe thunderstorm produced hail...from 1 to 1 3/4
        inches in diameter...near Lafayette...Louisville and Superior.
19    In 1874...during the afternoon...large columns of smoke from
        extensive fires in the mountain forests moved over the
        city from the west and southwest.
      In 1875...while no precipitation was measured in the city...
        rainfall over the Palmer Divide caused Cherry Creek to
        rise to the highest level in 10 years.
      In 1977...hail up to 2 inch diameter damaged two patrol cars
        in Castle Rock.
      In 1983  golf ball size hail fell just north of Bennett.
      In 1990...lightning from a thunderstorm struck the roof of a
        house in south Boulder.  Residents of the house were able
        to extinguish the ensuing fire with a garden hose...but not
        before several shingles had burned.
      In 1992...thunderstorms produced hail up to 2 inches in
        diameter in central Douglas County near Castle Rock.  Hail
        was 3 inches deep on I-25 south of Castle Rock.  A funnel
        cloud was sighted near Parker.
      In 1997...a 66-year-old man was knocked unconscious by a bolt
        of lightning while he was golfing at the Eagle Country
        Club in Broomfield.
      In 2000...dry microburst winds gusting to near 70 mph were
        reported across southeast Boulder and northern Jefferson
        counties.  Peak wind gusts included:  68 mph at the National
        Wind Technology Center...67 mph at Jefferson County Airport...
        and 65 mph in Broomfield.
      In 2001...severe thunderstorms produced large hail in the
        foothills southwest of Denver.  Hail as large as 1 3/4 inch
        in diameter fell near Conifer and Bailey.
      In 2002...lightning damaged the Evergreen Fire Protection
        District radio repeater.  One microwave transmitter...the
        main fire channel transmitter...and two solar panel
        controllers were destroyed.  Lightning struck a garage
        and caused a small fire.  Two vehicles parked in the garage
        were damaged.  Hail to 3/4 inch in diameter fell near Castle
        Rock.
      In 2004...severe thunderstorms produced hail to 3/4 inch in
        diameter near Castle Rock...Larkspur...and Golden.
      In 2018...very large hail pummeled portions of the Front Range
         Urban Corridor and extended across the northeast plains of
         Colorado. Reports of collapsed roofs due to hail were
         reported...with major hail portions of the Denver metro area.
         The Rocky Mountain Insurance Information Association
         estimated the property damage from the storm totaled 276.4
         million dollars...making it the 8th costliest hailstorm to
         strike the state to date.  In Denver and the surrounding
         metro area...hail sizes included:  3 inch diameter in
         Englewood; 2 3/4 inch in Greenwood Village; 2 inch at
         Aurora Cherry Creek...4 miles south of Glendale and near
         Smoky Hill; 1 3/4 inch just east of Denver International
         Airport and near South Glenn; 1 1/2 inch near Niwot; and 1
         inch diameter hail in Southwest Denver and 5 miles northeast
         of Parker.
      In 2022...a microburst wind produced a peak gust to 55 mph at
         Denver International Airport from the west. The visibility was
         briefly reduced to one half of a mile.
19-21 In 1875...from the 19th to the 21st...smoke from several large
        forest fires in the mountains was visible from the city on
        each of these days.
20    In 1888...northwest winds were sustained to 44 mph.
      In 1956...a microburst caused a brief wind gust to 58 mph at
        Stapleton Airport.
      In 1964...hail up to 1 inch in diameter was reported 1 mile
        north of Stapleton International Airport.  A 3 minute hail
        storm at both Stapleton International Airport and Lowry
        Field piled small hail to one half inch deep.
      In 1967...a strong thunderstorm dumped 1.95 inches of rain in
        less than an hour at Stapleton International Airport and
        produced a wind gust to 54 mph.  The storm caused some
        flooding in east Denver and Aurora.  There was widespread
        flooding to streets...basements...and store buildings and
        automobiles.  Hail stones to 3/4 inch in diameter were
        measured at Buckley Field in Aurora.  A tornado touched
        down just south of Littleton...damaging a barn and killing
        several head of cattle.
      In 1985...a wind gust to 61 mph was reported at Golden Gate
        Canyon in the foothills west of Denver.
      In 1986...a man was killed by lightning at Highlands Ranch
        south of Denver.
      In 1987...several tornadoes were sighted across metro
        Denver.  A tornado touched down briefly 5 miles west of
        Parker.  A tornado was sighted just north of Chatfield
        Reservoir.  A tornado just northwest of Watkins was on the
        ground for 15 minutes.  A tornado near Barr Lake was taped
        by a television news crew.  It had a double vortex and was
        on the ground for about 10 minutes.  In addition to the 4
        tornadoes...severe thunderstorms dumped large hail across
        metro Denver.  One inch hail was reported in southeast
        Aurora; 3/4 inch hail fell at the Denver Technology
        Center...Buckley Field...and Franktown.
      In 1992...several short-lived tornadoes occurred in the
        vicinity of Barr Lake.  No injuries or damages were
        reported.  A water spout was sighted over the southern end
        of Barr Lake.  Funnel clouds were also sighted on the
        grounds of the Rocky Mountain Arsenal by National Weather
        Service observers at Stapleton International Airport.
      In 1994...hail up to dime size covered I-25 south of Denver
        and near Sedalia.  Heavy rain caused local flooding on the
        Interstate highway.
      In 1996...strong thunderstorm winds downed several large tree
        limbs in Boulder on the University of Colorado campus.  A
        stop light in the city was also blown down.
      In 1999...lightning sparked an oil tank fire near Brighton.
      In 2001...large hail driven by strong thunderstorm winds raked
        Denver International and Front Range Airports.  Wind gusting
        to 54 mph along with hail as large 2 inches in diameter
        punched at least 14 thousand holes and cracks in the flat
        roofs of several buildings at Denver International Airport.
        In addition...93 planes and hundreds of cars were damaged.
        About 100 flights had to be cancelled...stranding 1500
        travelers.  The airport was completely shut down for about
        20 minutes.  The storm also damaged a ground avoidance radar
        used to track planes on the ground to prevent collisions.
        Damage was estimated at 10 million dollars...not counting the
        damage to the 93 airliners.  The storm moved south and
        struck Watkins with hail as large as 2 1/2 inches in
        diameter and winds gusting to 60 mph.  A least 30 private
        planes at Front Range Airport were destroyed.  The radome
        protecting the National Weather Service doppler radar...which
        was tracking the storm...also sustained damage.  The large
        hail...damaging winds...and heavy rain pummeled a mobile home
        park near Watkins.  In the park...52 mobile homes...14
        recreational vehicles...3 homes...and a commercial building
        were damaged.  Siding was riddled with holes and windows
        were broken.  Vehicles sustained extensive damage and car
        windows were shattered.  A handful of people were treated
        for minor cuts and bruises.  The strong winds also flipped
        a tractor trailer along I-70 near Watkins.  The storm caused
        power outages...which affected about 1200 residents.
        Excluding the damage at Denver International Airport...damage
        estimates totaled 49 million dollars...making the storm the
        costliest in the last 3 years and the 10th costliest since
        1984.  A small tornado touched down just east of Brighton...
        but did no damage.  Hail as large as 2 inches in diameter
        fell near Fort Lupton with 3/4 inch hail measured in
        Bennett.  Precipitation from the storm totaled only 0.23
        inch at Denver International Airport.
      In 2002...heavy rain fell near the Hayman Wildfire burn area.
        Flash flooding washed out a 40-foot section of the access
        road to Cheeseman Reservoir.  Some debris was washed against
        a gate...blocking the road.  Hail to 1 1/2 inches in diameter
        fell near Central City with 3/4 inch hail near Blackhawk.
      In 2003...hail as large as 1 inch in diameter fell near Bennett
        and Strasburg with 3/4 inch hail measured in Denver...Golden...
        at Centennial Airport...and near Parker.  Hail as large as
        7/8 inch was reported in Arvada.
      In 2004...a severe thunderstorm produced hail to 3/4 inch in
        diameter in and near Brighton.
      In 2005...severe thunderstorms produced large hail near the
        Palmer Divide.  Hail to 1 inch in diameter was measured
        near Larkspur with 7/8 inch hail near Sedalia and 3/4 inch
        hail in Greenland.  An apparent thunderstorm outflow produced
        a wind gust to 59 mph at Denver International Airport during
        the evening hours.
      In 2010...lightning struck a home in Centenniel and sparked a
        fire which caused extensive damage.
20-21 In 1897...high winds raked the city overnight.  Southeast winds
        were sustained to 60 mph with gusts as high as 72 mph on the
        20th.  Southeast winds were sustained to 57 mph with gusts
        to 60 mph on the 21st.
       In 2007...a brief hot spell produced two temperature records.
        The high temperature of 97 degrees was tied on the 20th.
        A new record high temperature of 99 degrees was established
        on the 21st.
21    In 1927...north winds were sustained to 40 mph with gusts to
        44 mph.
      In 1984...lightning struck and killed two children standing
        near a tree in a backyard in Lakewood.  Strong thunderstorm
        downbursts caused a wind gust to 58 mph in Northglenn and
        knocked down two power poles near Brighton.
      In 1988...lightning struck a home in Denver...causing about ten
        thousand dollars damage.  Lightning damaged 3 homes in
        Littleton...and also hit a house in Greenwood Village that
        had been struck by lightning 7 years previously.
      In 1991...thunderstorms produced widespread hail across metro
        Denver.  Hail as large as 2 1/2 inches fell at several
        locations across southwest metro Denver.  One storm spotter
        reported hail 8 inches deep near the intersection of I-25
        and C-470.  Heavy rain with the storms caused some street
        flooding.  In Commerce City...several cars were under water...
        and in Westminster a police officer reported water up to
        the doors of his car.  Damage to homes and automobiles
        totaled 55 million dollars.
      In 1992...a tornado touched down briefly near Bennett.
        Another tornado was briefly on the ground near Strasburg.
      In 1994...heavy thunderstorm rains caused flooding in metro
        Denver.  Several vehicles were stalled in the high water
        on I-25.  Lightning struck an underground natural gas line
        in Aurora...causing a fire.  Widespread power outages were
        also observed.
      In 1996...three homes were struck by lightning in Parker.
        The lightning struck the garage of the first home...which
        started a small fire that burned some siding and spread
        into the attic.  A second home sustained damage to the
        attic when a small fire was started.  The third home
        received only minor damage.  Lightning also sparked two
        small grass fires in the area.  A man in Lakewood received
        minor injuries when he was struck by lightning while
        working on a ladder.  A funnel cloud was sighted in Castle
        Rock.  Strong thunderstorm winds downed a large tree near
        Crossroads Mall in Boulder.  A small tornado (F0) briefly
        touched down near Lafayette.  No damage was reported.
      In 1997...one inch diameter hail was measured in Boulder.
      In 2002...a thunderstorm wind gust to 62 mph was recorded at
        Denver International Airport.
      In 2005...severe thunderstorms produced hail to 1 inch in
        diameter in Broomfield along with 3/4 inch hail near
        Arvada.
      In 2006...a man riding a motorcycle was struck and killed by
        lightning on U.S. Highway 36 between Church Ranch Blvd.
        and Sheridan Blvd. in Westminster.  After the biker was
        struck...he and his motorcycle crashed into the center
        concrete median of the highway.  The lightning bolt left
        a crater in the highway asphalt that measured 18 inches
        long...8 inches wide and 4 inches deep.
      In 2010...a severe thunderstorm produced hail up to 1 1/2
        inches in diameter near Morrison.  In Lafayette and
        Louisville...hail up to one inch in diameter was observed.
      In 2014...three small tornadoes touched down in eastern Adams
        County near Barr Lake...Bennett and Front Range Aiport.
        The tornado near Barr Lake damaged some out buildings and
        a storage shed. Minor roof damage to houses in the
        immediate area was reported near 168th Ave and Haymont Rd
        near 168th Ave and Haymont Rd. It was rated an EF1.  The
        others did no damage.
      In 2023...several rounds of large hail and heavy rain moved
        across Denver and the surrounding metro area.  The hail
        ranged in size from 1 to 2 inches in diameter...and caused
        extensive damage to home and vehicles. At Red Rock
        Amphitheatre a torrent of large hail and heavy rain
        blasted the venue.  Nearly 100 people attending a concert
        were injured.  Seven people were taken to hospitals with
        non-life-threatening injuries.  Most of the injuries
        included cuts...welts...bruises and broken bones...mainly
        fingers.  A few were treated for concussions.  Significant
        street flooding occurred in Denver...with storm totals of
        1 to 3 inches.  In Watkins...a flash flood fatality occurred
        along Watkins Avenue...just north of 6th Ave.  The incident
        occurred late in the evening.  The victim`s vehicle was swept
        off the roadway and she tried to cross an area of fast moving
        water overtopping the roadway.  Her vehicle was swept away
        under a bridge...about 400 yards downstream.  Two other vehicles
        were also trapped in the rushing water and the occupants had
        to be rescued.  A new daily record of 1.85 inches of rainfall
        was set for the date at Denver International Airport.
21-22 In 1941...strong thunderstorms produced cloudbursts of rain
        in Boulder County...starting during the late evening of the
        21st and continuing overnight into the 22nd.  The heavy
        rains over the Boulder Creek...Left Hand Creek...and South
        St Vrain River basins produced flooding in already swollen
        streams and turned dry gulches into raging torrents.  The
        force of the floodwaters swept a man from the arms of his
        wife to his death...severely damaged canyon homes and swept
        others away...and hurtled a car down a steep embankment
        after the driver narrowly escaped.  West of Boulder...the
        Boulder Canyon highway was littered with rocks and debris
        and collapsed when two culverts were washed away.  The
        flood waters washed much debris down Four Mile Canyon...
        damaging the road near the creek bed.  A bridge over Dry
        Creek just south of Niwot was completely washed away.
      In 1964...scattered hail and rain caused property damage and
        local flooding in Boulder.
      In 1989...an unseasonably cold weather system produced strong
        winds over much of metro Denver and snowfall in the
        foothills as low as 7500 feet elevation.  One to 6 inches
        of snow fell in the foothills west of Denver with 15 inches
        reported on the summit of Mount Evans.  Six inches of snow
        were measured at Conifer.  Rainfall totaled only 0.09 inch
        at Stapleton International Airport where northwest winds
        gusted to 29 mph on the 21st.
22    In 1872...small sandstorms...frequently seen on the prairie...
        occasionally passed through the city.
      In 1983...3/4 inch hail was observed at Deckers...and a
        thunderstorm produced wind gusts to 55 mph at Littleton.
      In 1988...a tornado was spotted one mile east of Brighton; it
        remained on the ground for about 6 minutes...but did no
        reportable damage.  Lightning damaged a home near Castle
        Rock.
      In 1991...thunderstorms produced golf ball size hail in
        Lafayette.  The strongest storms occurred north of metro
        Denver.
      In 1992...nickel size hail was reported just east of Parker.
      In 1995...large hail 3/4 to 1 3/4 inches in diameter fell in
        Castle Rock where a funnel cloud was sighted.  Hail 3/4
        inch to 1 inch in diameter fell in south Denver and Aurora.
        A funnel cloud was also sighted over Chatfield Reservoir.
        In Bennett...very strong dry microburst winds of unknown
        speeds ripped a 14-foot by 48-foot metal roof off of a
        barn. The roof was tossed approximately 250 yards. A few
        150- pound railroad ties were moved 10 to 15 feet.
      In 1997...a tornado touched down near the Adams County
        Fair Grounds northeast of Denver...uprooting several
        trees and damaging a car.  A dry microburst produced
        a brief wind gust to 69 mph at Jefferson County Airport.
        A small brief tornado was sighted near Hudson...but did
        no reported damage.
      In 1998...3/4 inch hail fell near Hudson.
      In 1999...thunderstorm winds gusted to 63 mph at Denver
        International Airport.
      In 2003...hail as large as 2 inches in diameter was measured
        in Fort Lupton with 3/4 inch hail in Erie and near
        Boulder.
      In 2006...a small tornado (F0) touched down near Franktown...
        but caused no damage.
      In 2008...strong winds from dry microbursts developed over
        parts of southern Weld and western Arapahoe Counties.
        A peak gust of 60 mph was observed in Centenniel.
        Near Frederick...strong winds snapped 3 power poles and
        sparked a small grassfire near State Highway 52 and
        Interstate 25.  At Denver International Airport...a peak
        gust of 31 mph was observed.
      In 2009...hail up to 2 inches in diameter was observed near
        Crescent in Boulder County.
      In 2023...an tornado touched down just south of CO-470
        in Highlands Ranch and lifted just west of I-25 near Lone
        Tree in Douglas County.  Most of the damage was EF0 but
        there were some pockets of EF1 damage; it was on the
        ground for 26 minutes.  The severe thunderstorm also
        produced large hail up to 2 1/2 inches in diameter.  The
        tornado track was from 2 miles west of Highlands Ranch to
        2 miles north-northeast of Surrey Ridge with a path length
        of 8.36 miles.  The maximum width of the tornado was
        approximately 50 yards There were no injuries.
22-26 In 2012...from the 22nd to the 26th...the maximum temperature
        exceeded 100 degrees for five consecutive days.  Two of
        the high temperatures on the 25th and 26th peaked at 105
        degrees...which set the all time record for the month of
        June and tied the all-time maximum temperature for Denver.

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