Public Information Statement
Issued by NWS Denver/Boulder, CO
NOUS45 KBOU 210045
Public Information Statement
National Weather Service Denver/Boulder CO
645 PM MDT SAT AUG 20 2016
...This week in metro Denver weather history...
19-30 In 1875...grasshoppers appeared in great numbers at 10:00 AM
on the 19th. Thousands landed on the ground. The streets
were literally covered with them. Swarms of grasshoppers
were seen on each day. All gardens in the city were
devastated...and in the countryside the grasshoppers were
very destructive to ripened grain. On the 30th the
grasshoppers were so numerous as to almost darken the sun.
21 In 1876...heavy thunderstorm rain and hail struck the city.
Hail stones as large as partridge eggs accumulated to a
depth of 1 1/2 feet over eastern portions of the city.
The heavy rainfall flooded streets and gutters. However...
no significant damage was reported. Rainfall totaled 0.85
inch in central Denver.
In 1903...a thunderstorm produced west winds sustained to
42 mph with gusts to 48 mph.
In 1957...heavy thunderstorm rainfall and hail over the Bear
Creek basin flooded portions of State Highway 8 in and near
Morrison. There was also minor property damage in Morrison.
In 1995...a 68-year-old woman was struck by lightning while
standing near a tree in Brighton.
In 2006...a severe thunderstorm produced 7/8 inch diameter
hail in Franktown.
22 In 1898...an apparent thunderstorm produced southwest
sustained winds to 40 mph with gusts to 43 mph.
In 1903...a late afternoon thunderstorm produced rain...hail...
and east winds sustained to 40 mph with gusts to 44 mph.
In 1904...the lowest recorded temperature in August...40
degrees...occurred. The same temperature also occurred on
three consecutive days...August 24...25...and 26 in 1910.
In 1965...heavy rain and hail caused some damage from flooding
over northern Douglas County from Castle Rock to Franktown.
In 1981...thunderstorms moved across metro Denver. At least
5 funnel cloud sightings were reported. Funnel clouds
were seen at 96th Ave. and Sheridan Blvd. and at 92nd Ave.
and Federal Blvd. in Westminster and 7 miles north of
Stapleton International Airport. Lightning injured two
people in Boulder. A quarter inch of rain fell in just
5 minutes in Brighton. Up to 3/4 inch of rain doused
Parker in 30 minutes.
In 1983...3/4 inch diameter hail was reported at Kittredge...
along with 0.60 inch of rain in 25 minutes.
In 1984...a thunderstorm dumped 4 inches of rain on Brighton
in 90 minutes...causing extensive street flooding in the
In 1987...over an inch of rain fell in 24 hours throughout
most of metro Denver. A public library suffered water
damage to the ceiling...carpet...and a few books. Rainfall
was 0.76 inch at Stapleton International Airport.
In 1990...lightning knocked out power to about 2500 homes in
Lakewood for about an hour.
In 1991...National Weather Service personnel at Stapleton
International Airport sighted an apparent tornado briefly
on the ground 3 miles west-northwest of the airport. No
damage was reported.
In 1995...lightning struck 3 electrical power substations in
Louisville. Residences of more than 4500 people were
without power from 30 minutes to more than an hour.
In 1996...between 1 and 3 inches of rain fell across metro
Denver. As a result...several low lying areas were flooded.
A bicyclist was swept into a fast moving creek when he
tried to cross a flooded bike path. The man was washed
downstream about 15 feet before getting snagged by a tree
stump. He and a man who tried to rescue him received
minor injuries. The heavy rain caused numerous power
outages...false fire alarms...and traffic accidents. In
Lakewood...telephone service to around 60 thousand
residents was knocked out when a switching center was
flooded. Funnel clouds were sighted near Chatfield
Reservoir and Highlands Ranch.
In 2000...lightning sparked a blaze which gutted a 10-unit
apartment building in Highlands Ranch. Twenty-eight
people were left homeless. Damage was estimated at
2 million dollars.
In 2007...severe thunderstorms produced large hail...up to
1 1/4 inches in diameter...in the vicinities of Castle Rock...
Elizabeth and Franktown.
In 2013...flash flooding occurred in central Douglas County
with numerous road closures reported. One of the closures
occurred at the Tomah Road exit along I-25...south of
Castle Rock. The closure backed up all I-25 the way to
Castle Rock. At Denver International Airport...1.94 inches
of precipitation was recorded...which set a new record
rainfall for the date. The old record was 0.75 inches...
set back in 1953.
22-24 In 1987...some locations in metro Denver had a total 3-day
rainfall of 2 to 4 inches. Rainfall totaled 0.96 inch
at Stapleton International Airport.
23 In 1900...northwest winds were sustained to 42 mph with
gusts to 49 mph.
In 1921...a thunderstorm cloudburst produced 2.20 inches of
rainfall in an hour over downtown Denver. This is the
greatest 1 hour rainfall on record at the official
observing site in the city. Precipitation totaled 2.93
inches...which is the greatest calendar day precipitation
ever recorded in August.
In 1941...one man was killed by lightning about 2 miles from
the official weather station in downtown Denver.
In 1962...a home near Boulder was destroyed by a lightning-
In 1968...strong winds buffeted Boulder briefly during the
early morning hours. At the National Center for
Atmospheric Research...winds averaged 55 mph with gusts to
85 mph. Damage was minor. Northwest winds gusted to
31 mph at Stapleton International Airport.
In 1977...lightning damaged at least 6 homes in Aurora.
In 2008...a landspout touched down near Westcreek in Douglas
County. One man was seriously injured when he tried to
escaped several falling trees in his ATV. One of the trees
struck his back and broke two vertebra. Another camper
narrowly escaped injury. Seconds after he back up his
truck...a tree came down where it had been parked.
24 In 1880...a thunderstorm produced vivid lightning and heavy
rainfall...which caused flooding over the eastern part of
the city including the brick yards. There was no rainfall
recorded in downtown Denver.
In 1910...an apparent dry cold front caused a remarkable drop
in temperature. From 3:00 PM until midnight the temperature
fell from a high of 93 degrees to a low of 40 degrees.
Northeast winds were sustained to 44 mph during the late
In 1946...heavy rain near Idledale caused flooding on Bear
Creek at Morrison...which resulted in one death when a
woman was swept from her stranded car and drowned.
In 1973...strong winds blew down a few power lines and hail up
to 3/4 inch diameter fell in southeast Aurora.
In 1984...heavy rain hit the south Denver area. Over an inch
fell in less than an hour at both Castle Rock and Sedalia.
In 1992...heavy rains caused flash flooding across parts of
metro Denver. Rainfall amounts of 1 to 3 inches fell with
the hardest hit areas being the southwest and central parts
of metro Denver. Bear Creek rose above bankfull near
Idledale with flood waters moving into southwest metro
Denver. Mud and rock slides along Colorado Highway 74 west
of Morrison were reported. The confluence of Cherry Creek
and the South Platte River in downtown Denver also went out
of its banks...flooding bike paths. Rainfall totaled 1.98
inches at Stapleton International Airport where light to
moderate rain fell most of the day. Heavy rain and fog
briefly reduced the surface visibility to 1 1/2 miles. The
temperature climbed to a high of only 58 degrees...which was
a record low maximum for the date.
In 2002...hail to 7/8 inch in diameter was measured in
In 2008...several landspout tornadoes developed along a boundary
to the southeast of the Denver metropolitan area during the
Democratic National Convention. In northwest Elbert County...
minor damage was reported. The damage consisted of downed
power lines...broken windows and an out building. Severe
thunderstorms also produced very heavy rain and large hail...
up to one inch in diameter. In southwest Douglas County...
heavy rain caused flash flooding near the town of Westcreek.
A mudslide closed State Highway 67. The road in the YMCA Camp
Shady Brook was also washed out and some bridges were damaged.
24-26 In 1910...the lowest temperature ever recorded in August...40
degrees...occurred on each of these days and on August 22...
1904. The unusually cold weather for so early in the
season brought sub-freezing minimum temperatures to much
of the Colorado northeastern plains.
25 In 1951...a microburst produced a southwest wind gust to 50
mph at Stapleton Airport. Only a trace of rain was
In 1964...thunderstorm winds gusted to 59 mph and caused
some blowing dust at Stapleton International Airport.
In 1994...lightning struck a power pole in Louisville and
caused a two-hour power outage.
In 2008...an unoccupied home was struck by lightning in Aurora...
causing 75 thousand dollars in damage to the roof.
26 In 1944...one of the most destructive hailstorms in the city
in a decade caused damage estimated at nearly one million
dollars. The storm occurred within a period of 10 to 30
minutes...between 2:00 PM and 3:00 PM. The hail varied in
size from very small to as large as 1 1/2 inches in
diameter. Hail covered the ground to a depth of 5 to 6
inches in some sections of the city. Several people were
cut by broken glass. The hail and heavy rain flooded
underpasses to a depth of 6 feet...and the occupants of
stalled autos had to be rescued. Sewers were unable to
handle the sudden amount of water and water backed up
and flooded a number of basements. A few first floors of
buildings were flooded. The Water Department had a busy
time replacing manhole covers that had been displaced by
the water pressure. Trees were stripped...one was severely
broken...and telephone lines were downed. Roofs...windows...
automobiles...awnings...and gardens were severely damaged.
Flowers and gardens in some sections of the city were a
total loss. Greenhouses were extensively broken with an
estimated 20 carloads of glass shattered. Vegetable and
truck crops in and around the city were severely shredded.
The next day the American Red Cross was designated by the
War Agency to grant any and all priorities needed to obtain
materials and supplies to replace and repair the damage.
In downtown Denver...the thunderstorm produced 0.95 inch of
rain and heavy hail along with sustained northwest winds to
In 1961...strong winds blew in the walls of a warehouse under
construction in Denver. Two workmen suffered a fractured
foot and body bruises.
In 2014...two men in central Denver were struck by lightning as
they sat under a tree to avoid a heavy downpour. One of the
men was unconscious and had no pulse when emergency
responders arrived. He was immediately taken to Denver
Health was listed in critical condition. The other victim
suffered less severe injuries. He was treated at the scene
and hospitalized...then released a few hours later.
26-27 In 1980...two heavy thunderstorms hit Arvada and Westminster...
dumping up to 1.50 inches of rain in less than an hour.
At least two streets were washed out and a number of homes
and cars were damaged when a creek flooded. Three homes
in Arvada sustained minor lightning damage.
27 In 1910...a thunderstorm produced south winds sustained to 40
In 1961...strong thunderstorm winds and heavy rain occurred at
79th and Federal Blvd. in Westminster. The strong winds
blew the roofs off lumber sheds onto parked cars.
In 1967...a young woman was killed by lightning while
horseback riding in the suburbs just west of Denver. Her
horse died several hours after the incident. A young man
and another young woman were also knocked from their horses
by the impact of the lightning and required hospitalization.
In 1991...heavy thunderstorm rainfall totaled 0.91 inch at
Stapleton International Airport...where 1/4 inch diameter
hail was measured.
In 1996...localized street flooding occurred in the Fort
Lupton area when 2 to 3 inches of rain fell in 45 minutes.
The roof of a community college began leaking...which caused
damage to ceiling tiles. The roof was under repair from
hail damage which had occurred earlier in the summer. A
weak tornado (F0) was sighted near Fort Lupton. No damage
In 1999...a slow moving thunderstorm dumped 5 inches of rain
in 2 hours near Dacono. A severe thunderstorm produced
3/4 inch diameter hail in Castle Rock.
In 2002...severe thunderstorms spread large hail over metro
Denver. Hail as large as 2 inches in diameter fell in
Jefferson County 5 to 11 miles northwest of Golden. Other
large hail reports included: 1 1/2 inches near Golden and
in Lakewood; 1 1/4 inches in Nederland; 1 inch hail near
Elizabeth...Louviers...Rollinsville...and Blackhawk; 7/8 inch
hail near Acequia in Douglas County. A thunderstorm
produced a trace of rain and a microburst wind gust to
52 mph at Denver International Airport.
In 2003...lightning struck a house and sparked a fire in
Arvada. Damage to the roof and ceiling was extensive.
In 2005...lightning struck an unoccupied home in Parker.
The resulting fire damaged the roof...attic...and second
floor bedroom. Damage was estimated at 15 thousand
27-28 In 2004...a brief chilly spell resulted in three temperature
records. The high temperature of 55 degrees on the 27th
was a record low maximum for the date. The low temperature
of 48 degrees on the 27th equaled the record minimum for
the date. The low temperature of 42 degrees on the 28th
was a record minimum for the date.