Tag Archives: October weather

September 27 to October 3: This week in Denver weather history

This Week In Denver Weather History
September 27 to October 3: This week in Denver weather history

With the end of summer and the arrival of fall, looking back at Denver weather history we start to see more mentions of snow.  It is of course not the only notable weather event this time of year.  We still have received severe thunderstorms, damaging winds, and 90 degree plus heat.

From the National Weather Service:

From the 25th to the 27th:

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.

From the 26th to the 28th:

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.

On the 27th:

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.

From the 27th to the 28th:

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.

On the 28th:

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 mph.

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.

From the 28th to the 29th:

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.

On the 29th:

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 airport.

Continue reading September 27 to October 3: This week in Denver weather history

October 2014 top shots: Monthly photo slideshow

October 1, 2014 - Sunrise at the Rocky Mountain Arsenal. (Ed Dalton)
October 1, 2014 – Sunrise at the Rocky Mountain Arsenal. (Ed Dalton)

October in Thornton can bring a wide variety of weather conditions, perfect for the photographer in all of us.

The month brings the changing of the colors at Colorado’s lower elevations and it is also is typically when we see our first freeze and first snow.  Couple those facts with our usual widely varying landscapes and wildlife and we have a month that is sure to bring in plenty of photo opportunities.

  • Slideshow updated October 31, 2014
  • To learn more about how to send your photo to us for inclusion in the slideshow, see below the slideshow.

Showcasing images captured by ThorntonWeather.com readers as well as some of our own, our monthly slideshow covers the entire gamut of weather-related imagery.

Sunsets, sunrises, wildlife and of course every type of weather condition are vividly depicted in images captured from yours and our cameras.

[flickr_set id=”72157648031120697″]

What is missing in the slideshow above?  Your photo!

Our monthly photo slideshow is going to feature images that we have taken but more importantly images that you have captured.  The photos can be of anything even remotely weather-related.

Landscapes, current conditions, wildlife, pets, kids.  Whimsical, newsy, artsy.  Taken at the zoo, some other area attraction, a local park, a national park or your backyard.  You name it, we want to see and share it!

Images can be taken in Thornton, Denver or anywhere across the extraordinary Centennial State.  We’ll even take some from out of state if we can tie it to Colorado somehow.

We’ll keep the criteria very open to interpretation with just about any image eligible to be shown in our slideshows.

What do you win for having your image in our slideshow?  We are just a ‘mom and pop’ outfit and make no money from our site so we really don’t have the means to provide prizes.  However you will have our undying gratitude and the satisfaction that your images are shared on the most popular website in Thornton.

To share you images with us and get them included in the slideshow just email them to us or share them with ThorntonWeather.com on any of the various social media outlets.  Links are provided below.

So come on, get those camera’s rolling!

Denver sets record high temperature for October 15

Record setting high temperatures in Thornton.As expected, temperatures in the Mile High City today were unseasonably warm and climbed to record-setting levels.  However, while Denver broke a high temperature record, Thornton fell quite a ways short.

Out at Denver International Airport, the mercury topped out at 83 degrees.  This bested the previous record high for the date of 82 degrees set in 2011 and previous years.

Here in Thornton, the cloud cover arrived earlier than the airport and impacted our readings.  We saw a maximum today of 77.9 degrees.

Across the board, temperature readings in the metro area were well above the average high of 66 degrees for the date.

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Thornton’s October weather preview: Fall begins to make its presence felt

Thornton, Colorado October weather preview.With the first full month of fall here, October usually brings one of the quietest weather months in the Denver area with plenty of mild, sunny days and clear, cool nights.

October is historically the second sunniest month and conditions are generally calm.

However we also will usually see our first taste of winter during the month with the first freeze and first snowfall of the season.  Temperatures as well will start to drop and by the end of the month the average nighttime lows are below freezing.

For complete details on our historical October weather and what we can expect in the coming month, read our complete October weather preview here.

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October 2013 weather recap: Cooler than normal temperatures, first snow recorded

Thornton and Denver’s October 2013 was overall a relatively un-noteworthy month in terms of weather.  Temperatures were below normal and we did receive our first measurable snowfall of the season.

We started the first two days of the month with temperatures in the 70s.  That was followed by a cold front moving through and delivering 0.8” of snow in Thornton on the 4th while Denver recorded only a trace at DIA.

We then saw five days of dry conditions with temperatures warming back up into the 70s.  On the 10th the next system arrived and rain was recorded on four of the next five days in Thornton.  Cooler than normal temperatures were notable during the period and lasted for the next eight days.

On the 18th another shot winter-like weather arrived and Thornton saw its biggest snowfall yet of the season: 2.4 inches.  Out at the airport, Denver recorded 1.4 inches.

The next nine days from the 19th to the 27th were largely pleasant days but with light rain on two days during that time.  On the 28th another cold front and storm system moved in and chilly temperatures returned.  Thornton recorded a dusting of snow on the 30th.

Overall temperatures for the month averaged 47.7 degrees as measured officially at DIA.  Here in Thornton our average temperature was slightly cooler at 45.9 degrees.  Both marks were considerably cooler than the historical October average temperature of 50.9 degrees.

Temperatures in Thornton ranged from a high of 79.5 degrees on the 8th down to a low of 25.5 degrees on the 16th.  Denver’s high and low were similar with 79 degrees also on the 8th and 27 degrees on the 5th and 16th.

One temperature record was set in Denver during the month.  On October 5 the low temperature reading of 28 degrees tied the record low for the date last set in 1877.

In terms of precipitation, Thornton recorded 1.21 inches between rainfall and snowmelt.  Denver was drier recording only 0.72 inches.  The Mile High City historically averages 1.02 inches so Thornton was above average, Denver below.

With only small snowfalls recorded, it wasn’t a particularly white month.  Thornton measured a total of 3.3 inches while Denver recorded only 1.4 inches.  Both were below the October average of 4.0 inches.

Click here to view Thornton’s October 2013 climate summary report.

[pe2-image src=”http://lh4.ggpht.com/-D-mSqpy-pQc/UnQi63nQ0FI/AAAAAAAAA3Q/_8y6TRKhmuE/s144-c-o/October2013Temps.jpg” href=”https://picasaweb.google.com/108306177534978229224/Misc?authkey=Gv1sRgCNPjmpm5l5PSOA#5941412203164913746″ caption=”Thornton’s October 2013 Temperatures.” type=”image” alt=”October2013Temps.jpg” pe2_single_image_size=”w560″ pe2_img_align=”left” ]

[pe2-image src=”http://lh5.ggpht.com/-d6PD6Dq3lto/UnQi_K0Q-dI/AAAAAAAAA3Y/L7pCMZAzn7E/s144-c-o/October2013Precip.jpg” href=”https://picasaweb.google.com/108306177534978229224/Misc?authkey=Gv1sRgCNPjmpm5l5PSOA#5941412277039200722″ caption=”Thornton’s October 2013 Precipitation.” type=”image” alt=”October2013Precip.jpg” pe2_single_image_size=”w560″ pe2_img_align=”left” ]

CLIMATE REPORT
NATIONAL WEATHER SERVICE BOULDER, CO
240 AM MDT FRI NOV 1 2013

...................................

...THE DENVER CO CLIMATE SUMMARY FOR THE MONTH OF OCTOBER 2013...

CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2013

WEATHER         OBSERVED          NORMAL  DEPART  LAST YEAR`S
                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
                                          NORMAL
................................................................
TEMPERATURE (F)
RECORD
 HIGH              90   10/01/1892
 LOW               -2   10/29/1917
HIGHEST            79   10/08        90     -11       83  10/03
LOWEST             27   10/16        -2      29       24  10/27
                        10/05
AVG. MAXIMUM     60.0              65.3    -5.3     62.2
AVG. MINIMUM     35.5              36.6    -1.1     35.9
MEAN             47.7              50.9    -3.2     49.0
DAYS MAX >= 90      0               0.0     0.0        0
DAYS MAX <= 32      0               0.4    -0.4        1
DAYS MIN <= 32     12               8.5     3.5       11
DAYS MIN <= 0       0               0.0     0.0        0

PRECIPITATION (INCHES)
RECORD
 MAXIMUM         4.17   1969
 MINIMUM            T   1934
TOTALS           0.72              1.02   -0.30     1.22
DAILY AVG.       0.02              0.03   -0.01     0.04
DAYS >= .01         8               5.3     2.7        5
DAYS >= .10         3               2.4     0.6        3
DAYS >= .50         0               0.5    -0.5        2
DAYS >= 1.00        0               0.1    -0.1        0
GREATEST
 24 HR. TOTAL    0.25   10/18 TO 10/18           10/24 TO 10/25
                        10/03 TO 10/04                    10/25 TO 10/25
                                                          10/25 TO 10/25
 STORM TOTAL       MM                                 MM
 (MM/DD(HH))            MM                    10/25(00) TO 10/25(00)
                                                 10/25(00) TO 10/25(00)5
                                                 10/25(00) TO 10/25(00)5

SNOWFALL (INCHES)
RECORDS
 TOTAL             MM   MM
TOTALS            1.4               4.0

DEGREE_DAYS
HEATING TOTAL     525               440      85      488
 SINCE 7/1        608               581      27      557
COOLING TOTAL       0                 5      -5        1
 SINCE 1/1        999               769     230     1236

FREEZE DATES
RECORD
 EARLIEST     09/08/1962
 LATEST       06/08/2007
EARLIEST      10/04             10/07
LATEST                          05/05
......................................................

WIND (MPH)
AVERAGE WIND SPEED              8.8
RESULTANT WIND SPEED/DIRECTION   1/180
HIGHEST WIND SPEED/DIRECTION    40/270    DATE  10/10
HIGHEST GUST SPEED/DIRECTION    48/270    DATE  10/10

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.50
NUMBER OF DAYS FAIR           12
NUMBER OF DAYS PC             14
NUMBER OF DAYS CLOUDY          5

AVERAGE RH (PERCENT)     61

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                0     RAIN                       3
LIGHT RAIN                9     FREEZING RAIN              0
LT FREEZING RAIN          1     HAIL                       0
HEAVY SNOW                1     SNOW                       2
LIGHT SNOW                4     SLEET                      0
FOG                      13     FOG W/VIS <= 1/4 MILE      9
HAZE                      4

-  INDICATES NEGATIVE NUMBERS.
R  INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T  INDICATES TRACE AMOUNT.

Trick or treat? Denver’s Halloween weather can be frightful but perhaps not as often as believed

Scary weather on Halloween in Denver? While it is oftentimes thought to be, that isn't usually the case.
Scary weather on Halloween in Denver? While it is oftentimes thought to be, that isn’t usually the case. (iStockPhoto)

Longtime residents of the Mile High City oftentimes have a belief that the weather on Halloween is frightful more often than not. A look at the empirical data shows that while some years have seen scary weather, most times it isn’t too bad.

Denver has been recording snowfall since 1882. In the 131 Halloweens from then until 2012, snow has fallen on October 31 just 22 times, or a mere 17%. That means historically there is less than a 1 in 6 chance of snow on All Hallows’ Eve.

Interestingly enough, there are better chances of snow falling on the day before Halloween and the day after. October 30 has recorded snowfall 21% of the time (28 times) and November 1 on 22% of the days (29 times).

Snow depth, measurable snow on the ground in the morning, has been recorded in the Mile High City since 1921. During those 91 years, snow was on the ground on Halloween morning 16% of the time (15 days).

Here again, there was snow on the ground more often on October 30 and November 1 than on Halloween itself. October 30 comes in with snow on the ground 17% of the time (16 times) and November 1 21% of the time (19 times).

However, when you combine the number of times snow was on the ground the day before, the day after or on Halloween itself, you can see where the perception of snowy Halloweens began. Totaling the three yields 50 days or 55% of the years.

Average temperatures on Halloween are actually relatively comfortable. Daytime highs average 51 degrees and lows dip to 31 degrees on average.

The highest temperature on the date was 79 degrees in 1950. The record low temperature for October 31 was recorded in 1991 at 10 degrees.

A few of the more notable Halloweens on record:

  • 2004 – The most recent time Denver received snow on Halloween when 1.4 inches was recorded.
  • 2002 – A white Halloween and a very cold one! 1.2 inches of snow was recorded and temperatures during prime trick-or-treating time were only in the mid to upper teens. The high temperature that day, 19 degrees, stands as the record low maximum temperature for October 31.
  • 1972 – The snowiest Halloween on record. The high temperature that day was only 30 degrees with a low of 15 degrees. Eight inches of snow fell that day followed by an additional 5.8 inches on November 1.

What does Halloween 2013 hold in terms of weather? Click here for the latest forecast.

Don’t miss a thing when it comes to our ever-changing weather! Be sure to ‘like’ us on Facebook, follow us on Twitter and add us to your Google+ circles.

Hunter’s Moon brightens the early morning sky

Sunday morning the virtually full moon brightened the landscape.  Captured just before dawn, the image below is technically two days late to be one of the truly full Hunter’s moon but it still appears fully lit.

The Hunter’s Moon is the traditional term for the second full moon of autumn, following the Harvest Moon, the first of the season.  Typically this makes it the full moon we see in October but it can sometimes fall in November.

The name is popularly attributed to Native Americans and said to be named such because it meant it was time to go hunting and prepare for the arrival of winter.

More than folklore, there is something unique about the Hunter’s Moon.  See below the image for more details.

A very bright moon lights up the landscape two days after the full Hunter’s Moon.  Click the image for a larger view.
A very bright moon lights up the landscape two days after the full Hunter’s Moon. Click the image for a larger view. (ThorntonWeather.com)

From EarthSky.org:

But the Hunter’s Moon is also more than just a name. Nature is particularly cooperative around the time of the autumn equinox to make the full moonrises unique around this time.

Here’s what happens. On average, the moon rises about 50 minutes later each day. But when a full moon happens close to the autumnal equinox – either a Harvest or a Hunter’s Moon – the moon (at mid-temperate latitudes) rises only about 30 to 35 minutes later daily for several days before and after the full moon.

Why? The reason is that the ecliptic – or the moon’s orbital path – makes a narrow angle with the evening horizon around the time of the autumn equinox. The narrow angle of the ecliptic results in a shorter-than-usual rising time between successive moonrises around the full Hunter’s Moon.

These early evening moonrises are what make every Hunter’s Moon special. Every full moon rises around sunset. After the full Hunter’s Moon, you’ll see the moon ascending in the east relatively soon after sunset for a few days in a row at northerly latitudes.

Denver ties record low temperature for October 4

Record Cold TemperaturesWith a Freeze Warning in place following yesterday’s cold front, we knew it was going to be cold and it certainly has been.  In fact, it was record-setting.

Just before midnight, the mercury at Denver International Airport dropped to 28 degrees.  This tied the record low temperature for the date, October 4, last set 136 years ago in 1877.

Thornton nearly matched the official Denver numbers with a low of 28.5° recorded at 11:57 p.m.  This was our coldest reading since May 3.

The storm system that moved through brought snow to a good part of the Denver metro area.  Here in Thornton we measured 0.8”, our first snowfall of the season.  A total 0.39″ of liquid precipitation (rain and snow melt) was recorded in our bucket.

Inexplicably, the National Weather Service is showing no snow was measured at DIA yesterday morning.  This despite the fact that numerous firsthand accounts and pictures posted to social media showed the airport did indeed have measureable snowfall.

We are reaching out to the NWS to get an explanation for the discrepancy and will update this post if / when we receive a response.

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September 28 to October 5: This Week in Denver Weather History

This Week In Denver Weather History
September 28 to October 5: This Week in Denver Weather History

While it appears Denver will escape September snow, our look back at this week in weather history shows that isn’t always the case. Additionally, while not common, even early fall can bring severe weather with damaging wind, lightning and even tornadoes.

From the National Weather Service:

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.

30

In 1898…south winds were sustained to 41 mph with gusts to 54 mph.

In 1940…a late season thunderstorm in the city caused one lightning death.

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 1892.

In 2009…a trained spotter in Coal Creek Canyon…recorded a peak wind gust to 88 mph.

Continue reading September 28 to October 5: This Week in Denver Weather History

Thornton’s October weather preview: First freeze, first snow usually coming

Thornton, Colorado October weather preview.With the first full month of fall here, October usually brings one of the quietest weather months in the Denver area with plenty of mild, sunny days and clear, cool nights.

October is historically the second sunniest month and conditions are generally calm.

However we also will usually see our first taste of winter during the month with the first freeze and first snowfall of the season.  Temperatures as well will start to drop and by the end of the month the average nighttime lows are below freezing.

For complete details on our historical October weather and what we can expect in the coming month, read our complete October weather preview here.

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