Public Information Statement
Issued by NWS Denver/Boulder, CO
NOUS45 KBOU 250045
Public Information Statement
National Weather Service Denver/Boulder CO
645 PM MDT SAT SEP 24 2016
...This week in metro Denver weather history...
25 In 1873...a fire was sighted in the woods near Platte Canyon...
probably caused by high winds blowing sparks among the
In 1896...an apparent cold front produced northeast sustained
winds to 40 mph with gusts to 48 mph.
In 1910...a thunderstorm produced sustained north winds to
51 mph. This was the highest recorded wind speed in the
city in September at the time.
In 1936...a vigorous cold front produced a deadly dust storm
in the city. North winds sustained to 36 mph with gusts
to 38 mph produced much blowing dense dust...greatly
restricting the visibility. The temperature plunged from
a high of 84 degrees to a low of 38 degrees by midnight.
The weather observer described the event with the following.
"At 6:00 PM the temperature was 82 degrees and the wind
velocity was only 4 mph; but with the wind shifting to the
north and the barometer rising quite rapidly...the temperature
fell sharply. By 6:30 PM...the wind velocity increased
rapidly and by 7:00 PM had reached a maximum sustained
velocity of 36 mph...bringing with it clouds of dust which
had been picked up by gale force winds in southern Wyoming
and northern Colorado...covering the city. The visibility
was generally reduced to about 1/4 mile; however...the
whirling of the dust down the streets and alleys...the
visibility was at times somewhat less. Airplanes were
grounded...traffic was halted at times...and homes filled
with dust. The strong winds damaged electric power and
telephone lines...leaving homes in darkness for a few hours
in the city and for 18 hours in suburban towns and putting
2500 telephones out of service because of broken lines. An
electric lineman was killed while repairing damage by the
high winds. The dust storm was followed by rain that began
falling at 10:55 PM...which turned to snow during the early
morning hours of the 26th. A major snow storm followed on
the 27th through the 29th."
In 1999...high winds developed in the foothills of Boulder
County. Winds gusted to 90 mph at Wondervu.
25-26 In 1908...apparent post-frontal rain changed to snow overnight
and totaled 6.5 inches in downtown Denver. This was the
first snow of the season. Precipitation totaled 0.76 inch.
North winds were sustained to 39 mph on the 25th.
25-27 In 1996...an early season snowstorm brought heavy snow
to the Front Range eastern foothills. Snowfall totals
included: 8 to 12 inches around Conifer...7 inches on
Floyd Hill...and 6 inches at both Bailey and Chief Hosa.
Snowfall totaled only 4.7 inches at the site of the
former Stapleton International Airport. This was the
first measurable snow of the season. After the passage
of a strong cold front...north winds gusted to 38 mph at
Denver International Airport on the 25th.
26 In 1907...a late afternoon thunderstorm produced hail...0.23
inch of precipitation...and north winds sustained to 24 mph.
In 1927...snowfall of 1.7 inches...mixed at times with sleet...
was the first measurable snowfall of the season.
In 2012...a man was seriously injured when he was struck by
lightning outside the Hebrew Educational Alliance as he
and his family were getting in their car. The victim
stopped breathing but was saved when his wife performed
cardiopulmonary resuscitation on him immediately
following the lightning strike. He suffered burns to 15
percent of his body which included his legs...chest...
abdomen and neck. Lightning also caused 48 outages in
Denver which affected 6582 Xcel Energy customers.
26-28 In 1936...the heaviest snowfall ever recorded in September
and the heaviest snowfall ever recorded so early in the
season dumped a total of 16.5 inches of snow on downtown
Denver and 21.3 inches at Denver Municipal Airport. The
15.0 inches of snow measured from 6:00 PM on the 27th to
6:00 PM on the 28th is the greatest 24 hour snowfall ever
recorded in September. This was the first snow of the
season. The snow was intermittent through the 26th...but
continuous from early afternoon on the 27th to around
midnight on the 28th...except for a period of rain during
the afternoon of the 28th which contributed to a loss of
depth on the ground. The greatest snow depth on the ground
downtown was 13 inches with 8 inches at Denver Municipal
Airport. There were no high winds with the storm and
traffic was interrupted for only a short period. The
storm produced property damage estimated at 7 million
dollars. With trees and shrubs in full foliage...the leaves
caught and held the heavy water-laden snow...until the
branches snapped from the weight. More than 3000 workmen
were called to remove the debris and snow from the city. The
city firemen who were off duty...as well as all the reserves...
were asked to report to their stations. All schools in the
city remained open...but attendance was only 50 percent of
normal. Grade school students were sent home at noon on the
28th. The early storm caught stockmen with many cattle still
in higher ranges. Warm weather followed the snow...which had
all melted by the end of the month...except for a few inches
in sheltered places.
27 In 1877...smoke from heavy forest fires in the mountains
spread over the city on upper wind currents.
In 1935...the first snow of the season was 2.8 inches in
downtown Denver. The low temperature dipped to 31
degrees for the first freeze of the season.
27-28 In 1984...heavy snow fell over the plains and foothills.
Snowfall amounts ranged from 2 to 5 inches on the plains
with up to a foot at higher elevations in the foothills.
The main problem caused by the storm was thousands of
power outages caused by snow-laden tree limbs snapping and
falling onto power lines. Over 15 thousand homes lost
power in metro Denver. Some cars were damaged by falling
trees and limbs. The snow also caused some flight delays
at Stapleton International Airport where 5.1 inches of
snow fell and northeast winds gusted to 29 mph. Maximum
snow depth on the ground was 3 inches due to melting. The
high temperature of only 34 degrees on the 28th was a
record low maximum for the date and equaled the all-time
record for the month at that time.
28 In 1877...heavy dense smoke from mountain forest fires spread
over the city. The smoke was so dense that it obscured the
sun at times.
In 1921...post-frontal northeast winds were sustained to 44
In 1953...a Pacific cold front produced a west wind gust to 59
mph at Stapleton Airport where the visibility was briefly
reduced to 3/4 miles in blowing dust. Strong winds were
also widespread over Boulder during the afternoon.
In 1960...strong...gusty winds tore the roof from 6 units of a
motel on west Colfax Avenue in Denver. The roofing sailed
over the building and crashed down on a truck...wrecking it.
The strong winds were the result of an apparent microburst.
In 1999...snow fell in the foothills west of metro Denver and
over the plains. Snowfall totals included 7 inches at
Conifer. At the site of the former Stapleton International
Airport...3.1 inches of snow were measured. This was the
first snow of the season. The heavy wet snow snapped
branches from fully leafed trees...downing power lines and
causing scattered outages.
In 2004...severe thunderstorms produced hail to 3/4 inch in
diameter in Littleton and in Douglas County 14 miles
northwest of Castle Rock.
In 2012...a weak tornado (EF-0) tornado touched down near
Strasburg. No damage was reported.
28-29 In 1959...one of the heaviest September snow storms of record
began as rain and changed to heavy wet snow. The storm
caused heavy damage to trees and shrubbery...which were
still in full leaf. The storm dumped 10.6 inches of snow
at Stapleton Airport...the third heaviest September snow
amount to date. Falling trees and limbs disrupted
traffic...broke power and communication lines...and damaged
buildings and cars. One man was killed in Denver by a
falling tree limb...and four others died of heart
attacks while shoveling snow or trying to move heavy
tree limbs. Direct costs of the storm for cleaning up
debris...repairing utility lines...and damage to buildings
and other property across all of eastern Colorado were
estimated to be over a half million dollars. The value
of trees destroyed or damaged was estimated to exceed
five million dollars. North-northeast winds gusted to
32 mph at Stapleton Airport on the 28th.
In 1985...an unusually cold air mass for this time of year
settled over the area. Metro Denver received 8 to 12
inches of powdery snow. The 8.7 inches of snow that
fell at Stapleton International Airport was the first
measurable snow of the season and the city`s heaviest
September snowfall since 1971. The snow caused flight
delays of over 2 hours at Stapleton International Airport.
I-70 was closed for a time west of Denver. Snow-laden
tree limbs snapped over all of metro Denver...causing
widespread power outages. Ten thousand people were without
electricity for a time in Boulder. The morning of the 29th
saw mid-winter temperatures along the Front Range. The
temperature dipped to 17 degrees...the lowest temperature
ever recorded in September in Denver. The high temperature
of only 29 degrees on the 29th was a new record low maximum
for the date and lowest ever recorded during the month of
September. The low temperature of 21 degrees on the evening
of the 28th set a new record low for the date. The cold
weather persisted through the 1st with record minimum
temperatures of 25 degrees set on the 30th and 27 degrees
set on October 1st.
29 In 1966...a vigorous cold front moved thru metro Denver.
North winds gusting to 51 mph kicked up billows of blowing
dust...which briefly reduced the visibility to 1 mile at
Stapleton International Airport. The cold air caused
temperatures to drop rapidly from a high of 86 degrees to
a low of 46 degrees by days end.
In 1985...the lowest temperature ever recorded in September...
17 degrees...occurred. The high temperature warmed to only
29 degrees...the all-time record low maximum for the month.
In 1994...the temperature reached a high of 91 degrees at
Stapleton International Airport. This was the 60th day
of the year that the temperature had reached 90 degrees
or more...establishing a new record at that time. The
previous record of 52 "90 degree days" occurred in 1978.
Only 43 "90 degree days" were recorded at Denver
International Airport during 1994.
In 1995...lightning struck a couple in Aurora as they were
walking in the rain. The bolt struck the umbrella the man
was carrying...injuring both the man and his wife.
In 2000...late afternoon thunderstorms produced strong wind
gusts to 76 mph in Westminster...to 69 mph near Boulder...and
to 60 mph at Jefferson County Airport near Broomfield. No
damage was reported.
In 2014...a storm system that moved through the area produced
large hail and street flooding in parts of metro Denver and
then spread east into the plains. The storm also caused
multiple accidents. A semi became detached from a trailer...
blocking traffic on westbound Interstate 70 west of Tower
Road. Downed power poles blocked a roadway on CO 79 near
Bennett...at mile marker 10. In addition to the damaging
winds...the storms produced large hail...from nickel to
golfball size across southern and eastern portions of
metro Denver. The hailstorm was the most damaging of
the 2014 summer season...with insured losses that topped
213 million dollars. Insurance claims included 29297
automobile claims worth more than 87.2 million dollars and
14287 property claims for 126 million dollars...ranking
the storm as the eighth most expensive to hit the state. At
Denver International Airport...1.01 inches of rainfall was
recorded which was the greatest 24-hr rainfall for the date.
In addition...a peak wind gust to 38 mph was observed at the
30 In 1898...south winds were sustained to 41 mph with gusts to
In 1940...a late season thunderstorm in the city caused one
In 1944...the month ended with a trace of rain on this date
and for the month. A trace of rain also occurred on the
4th...9th...and 10th. There was no measurable precipitation
for the month. The total of a trace of precipitation for
the month equaled the driest September on record first set
In 2009...a trained spotter in Coal Creek Canyon...recorded a
peak wind gust to 88 mph.
30-1 In 1959...heavy snowfall totaled 5.9 inches at Stapleton
Airport. Winds were light.
1 In 1892...the highest temperature ever recorded in October...
90 degrees...occurred. This is also the latest 90 degree
reading of the season.
In 1898...southwest winds were sustained to 40 mph with
gusts to 49 mph in the city.
In 1927...a trace of snow was the only snow of the month...
ranking the year...amongst several other years...the
second least snowiest on record.
In 1971...a wind gust to 90 mph was recorded at Buckley
Field in Aurora. The severe winds caused damage in
northeast metro Denver. A brick wall of a bowling alley
was blown down...the roof was blown off a garage...and some
business signs were damaged. A man in the bowling alley
was injured by flying glass. Northwest winds gusted to
43 mph at Stapleton International Airport.
In 1994...unusually strong thunderstorms for so late in the
season pummeled metro Denver with large hail. The largest
hail...2 inches in diameter...fell at Buckley Field. Hail
1 3/4 inches in diameter fell 7 miles northeast of Boulder
and at Niwot. Hail 3/4 to 1 1/2 inches in diameter fell in
Boulder...Arvada...Wheat Ridge...Edgewater...Capitol Hill and
northwest Denver...Bennett...and Strasburg. Hail of unknown
size damaged a Boeing 737 aircraft and injured both pilots
at Stapleton International Airport when the windshield was
broken out on takeoff. Half inch diameter hail fell at
Stapleton International Airport where northwest winds
gusted to 40 mph and rainfall totaled 0.82 inch.
In 2009...strong downslope winds near the foothills produced
a peak wind gust to 84 mph at the National Wind Technology
Center near Rocky Flats.
In 2014...severe thunderstorms produced wind gusts to 60 mph
across parts of Arapahoe and Denver Counties. The intense
wind gusts downed trees and power lines which caused a
power outage near the Denver Technology Center. At Denver
International Airport...a peak wind gust to 37 mph was
measured from the northwest.