October 17 to October 23 – This week in Denver weather history
This year Denver is still waiting for its first snowfall but that certainly has not been the case throughout history. Many times in our past we have seen not only snow around this time of October but heavy snow as well, oftentimes damaging in nature.
15-17
In 1989…an autumn snowstorm hit metro Denver with 2 to 6 inches of snow. Snowfall totaled 4.4 inches at Stapleton International Airport where the maximum snow depth on the ground was only 3 inches due to melting and north winds gusted to 25 mph on the 15th. The heavy wet snow caused leafy branches to sag onto power lines…resulting in a number of power outages. Five thousand homes were blacked out in Boulder on the 16th. Up to a foot of snow fell in the higher foothills with 19 inches recorded at Echo Lake.
16-17
In 1990…strong downslope winds raked the eastern foothills. Wind gusts from 60 to 75 mph were common. Strong winds in metro Denver resulted in wave damage to a dock used to moor several private sail boats at Cheery Creek Reservoir. Damage was confined to the dock and two anchor cables. A northwest wind gust to 43 mph was recorded at Stapleton International Airport.
17
In 1878…strong winds reached sustained speeds of 48 mph.
In 1988…a wind gust to 62 mph was recorded in central Boulder. The strong winds caused a few brief power outages. An old smoldering brush fire in the foothills west of Boulder was re-ignited by the wind gusts.
In 1994…winds gusted to 85 mph atop Squaw Mountain…5 miles south of Idaho Springs.
In 2006…a potent storm system brought heavy snowfall to the mountains and eastern foothills. Snowfall totals in the foothills included: 14 inches at Blackhawk…13.5 inches near Idaho Springs…13 inches at cabin creek…12.5 inches at Aspen Springs and Echo Lake…11.5 inches at Georgetown and Rollinsville…10.5 inches near Jamestown…and 10 inches at grant and Lake Eldora. Lesser snow amounts…from 4 to 9 inches…were recorded elsewhere in the foothills. Snowfall totaled only 3.5 inches in the Denver Stapleton area. At Denver International Airport…north winds gusted to 31 mph.
October 10 to October 16 – This week in Denver weather history
The farther we get into fall the more we start seeing significant snow events in our look back at the week in history. None of these is more famous than the “Bronco Blizzard” of 1984 that saw the Mile High City buried under nearly a foot of snow – on live television.
From the National Weather Service:
9-10
In 2005…a major winter storm brought heavy…wet snowfall to the Front Range mountains…eastern foothills…portions of metro Denver…and the Palmer Divide. Snow accumulations ranged from 8 to 26 inches with drifts from 3 to 4 feet in places. The heaviest snow occurred to the east and southeast of the city…closing most major highways in that area…including I-70 from Denver to Limon. The Red Cross opened four shelters for people who were stranded along I-70 in eastern Colorado. Since many trees had not yet shed their leaves…the storm caused significant tree damage. One woman in Denver was killed when a tree branch… 8 to 10 inches in diameter…snapped under the weight of the heavy…wet snow and struck her as she was shoveling her driveway. Xcel Energy reported power outages to about 35 thousand customers. Several incoming flights were delayed at Denver International Airport. Snow totals included: 16 inches in the foothills near Boulder…12 inches at Genesee and near Golden…22 inches near Watkins…19 inches near Bennett…17 inches southeast of Aurora…14 inches near Parker…13 inches near Castle Rock…12 inches in centennial… 11 inches in Parker…and 10 inches at Denver International Airport and in Littleton. While many areas of metro Denver received heavy snow…others experienced almost entirely rain. This included west and northwest metro Denver…Boulder…and Longmont. Rainfall amounts were significant as storm totals ranged between 1.50 and 2.50 inches. The steady rainfall triggered 3 rockslides in foothills canyons. Two of the slides occurred on State Highway 119 in Boulder canyon and the longest slide…7 feet in length…on State Highway 74 in Bear Creek Canyon at Idledale. North winds were sustained to around 23 mph with gusts to 31 mph at Denver International Airport on the 9th. The high temperature of only 34 degrees on the 10th was a record low maximum for the date. The low temperature on both days was 32 degrees.
10
In 1901…an evening thunderstorm produced east winds to 43 mph with gusts to 48 mph.
In 1949…strong winds believed to be the worst in Boulder’s history at the time caused over 100 thousand dollars damage in the city. Peak winds were estimated to 85 mph at Valmont…just east of Boulder. High winds also occurred over most of metro Denver and caused damage to trees…window glass…and utility lines. The damage was most pronounced over the northwest metro area…including north Denver and Lakewood. Falling tree branches caused damage to parked autos and houses. Wind gusts to 70 mph were recorded at Stapleton Airport.
In 1964…lightning struck and killed a 13-year-old boy…while he was riding his bicycle along a tree-lined residential street in south Denver. Apparent microburst winds gusted to 54 mph at Stapleton International Airport.
"Tornado tourism" is becoming a quickly growing industry as folks look for alternatives to a trip to the beach. Check out the slideshow below to see what a one week tour yielded this past summer. (ThorntonWeather.com)
While many might view a tornado something to flee from, an increasing number of vacationers are flocking to the Great Plains for the chance to get up close and personal with a twister. A new study shows that storm chasing tours are becoming a vacation of choice for not only many Americans but also visitors from overseas.
A University of Missouri research team found that interest in tornado chasing is being fed by popular television shows like the Discovery Channel’s Storm Chasers. Further, thanks to the power of the Internet, live video streams by storm chasers showing tornadoes as they rip across the landscape have skyrocketed in popularity.
Tornado Alley stretches across the nation’s midsection and is a unique location as most of the world’s tornadoes occur in this broad swath from South Dakota to Texas. Tour operators like Silver Lining Tours have capitalized on tourists seeking something more adventurous than a day at the beach.
Researchers Sonja Wilhelm Stanis and Carla Barbieri said that while the majority of participants in these tours were American, there was an international flavor to them as well. “While more than half of the surveyed travelers lived in North America, 11 percent came from Australia and nearly a third traveled from Europe to get a close encounter with a tornado.”
Demographics for the group ran the entire gamut from married couples to singles aged from 25 to 55. Their backgrounds were as varied as one would expect at any vacation destination with blue collar workers and urban professionals all among the participants.
The study found that most that chose this high-risk activity were satisfied with the experience, even if they did not see a tornado. One-third of them saw a tornado while 50% saw funnel clouds. The vast majority, 95%, at least saw a “significant atmospheric event.”
The Dominator team led by Reed Timmer are one of three groups of chasers in this season of Storm Chasers. (Discovery Channel)
Every spring and summer storm chasers take to the Great Plains on a single-minded quest to experience a tornado up close and personal. While many people may find this odd, the cast of the Discovery Channel series Storm Chasers relishes the annual ritual and the channel is set to kick off the fourth season of the hit series.
The 1996 movie Twister brought storm chasing on to the big screen and to the forefront of the public consciousness. On the small screen, Storm Chasers has become one of the most popular shows on Discovery Channel as camera crews follow teams of professional chasers hunting tornadoes. Both have been responsible for the increasing interest in “tornado tourism” during severe weather season.
For the 2010 season the show sees the return of familiar faces for those that have seen the show before but also a notable one appears to be missing.
The Mile High City's September weather was unusually dry and warm. (iStockphoto / johnnyscriv)
Wildfires and record-setting temperatures provided a clue as to what the highlights of September’s weather would be and with the month over we now see it in the statistics. September 2010 will go down in the record books as not only one of the driest Septembers on record but also one of the warmest.
A mere 0.06 inch of precipitation was recorded at the official monitoring station at Denver International Airport over the month. Most of that fell during a four-day period from the 18th to the 22nd and in the end 25 days had no moisture at all. That scarcity of precipitation allowed the month to finish in a tie with 1882 and 1920 for the 5th driest September on record. Here in Thornton we fared a bit better having recorded 0.09 inch of precipitation but that paltry difference is not hardly worth noting.
Not only was precipitation in short supply, so too were even clouds. Zero days were reported as cloudy, 10 days as partly cloudy and 20 days were fair (sunny). Thornton recorded over 200 hours of sunshine for the month – more than any other month in 2010.
Temperatures were well above normal for the month and into top 10 status as well. The average temperature of 67.0 degrees was 4.6 degrees above normal. This puts September 2010 in a tie with 1939 as the seventh warmest September on record. Thornton was thankfully quite a bit cool as we recorded an average temperature of 64.7 degrees.
Four record high temperatures were tied or broken during the month. On the 19th a scorching 96 degrees was recorded easily besting the old record for the date of 93 degrees last set in 1980. That also was the hottest temperature ever recorded that late in the season. Other dates this past month setting records were: 94 on the 20th beating the old record of 92 last set in 1956; tied the record on the 26th with 1892; 92 on the 28th topping the old record of 89 last set in 1994.
In all the month recorded eight 90 degree days, well above the normal of 2 for September. An amazing 25 days had temperature at or above 80 degrees which is the highest number of 80 degree temperatures in September since 1872. Overall temperatures ranged from the high of 96 on the 19th down to a low of 40 on the 3rd. Thornton’s temperatures ranged from a high of 93.6 on the 19th to a low of 40.7 degrees on the 7th.
Looking beyond the statistics, the most noteworthy events of September 2010 were the wildfires in the foothills west of Denver. The Fourmile Canyon Fire northwest of Boulder became the most destructive in state history in terms of the number of homes destroyed. West of Loveland the Reservoir Road Fire claimed homes as well but was thankfully controlled relatively quickly due to the quick response of firefighters.
What does the October 2010 weather hold for Denver and the Colorado Front Range? Right now the dry and warm weather is expected to continue. Get all the details in our October 2010 preview.
From the National Weather Service:
...THE DENVER CO CLIMATE SUMMARY FOR THE MONTH OF SEPTEMBER 2010...
CLIMATE NORMAL PERIOD 1971 TO 2000
CLIMATE RECORD PERIOD 1872 TO 2010
WEATHER OBSERVED NORMAL DEPART LAST YEAR'S
VALUE DATE(S) VALUE FROM VALUE DATE(S)
NORMAL
................................................................
TEMPERATURE (F)
RECORD
HIGH 97 09/04/1995
09/01/1995
09/04/1960
09/05/1899
LOW 17 09/29/1985
HIGHEST 96 09/19 97 -1 91 09/01
LOWEST 40 09/03 17 23 36 09/28
AVG. MAXIMUM 84.8 77.4 7.4 78.0
AVG. MINIMUM 49.1 47.3 1.8 48.9
MEAN 67.0 62.4 4.6 63.5
DAYS MAX >= 90 8 2.2 5.8 1
DAYS MAX <= 32 0 0.2 -0.2 0
DAYS MIN <= 32 0 0.8 -0.8 0
DAYS MIN <= 0 0 0.0 0.0 0
PRECIPITATION (INCHES)
RECORD
MAXIMUM 4.67 1961
MINIMUM T 1892
1944
TOTALS 0.06 1.14 -1.08 0.74
DAILY AVG. T 0.04 -0.04 0.02
DAYS >= .01 3 6.3 -3.3 5
DAYS >= .10 0 MM MM 4
DAYS >= .50 0 MM MM 0
DAYS >= 1.00 0 MM MM 0
GREATEST
24 HR. TOTAL 0.03 09/22 TO 09/22 0.42 09/22 TO 09/23
SNOWFALL (INCHES)
RECORDS
TOTAL 17.2 1971
TOTALS 0.0 2.1 0.0
DEGREE_DAYS
HEATING TOTAL 32 136 -104 117
SINCE 7/1 35 146 -111 139
COOLING TOTAL 100 57 43 78
SINCE 1/1 862 696 166 533
FREEZE DATES
RECORD
EARLIEST 09/08/1962
LATEST 06/08/2007
EARLIEST 10/07
LATEST 05/05
.................................................................
WIND (MPH)
AVERAGE WIND SPEED 9.3 9.2
RESULTANT WIND SPEED/DIRECTION 2/190
HIGHEST WIND SPEED/DIRECTION 37/310 09/06 36/210 09/30
HIGHEST GUST SPEED/DIRECTION 44/320 09/06 45/280 09/30
SKY COVER
POSSIBLE SUNSHINE (PERCENT) MM
NUMBER OF DAYS FAIR 20
NUMBER OF DAYS PC 10
NUMBER OF DAYS CLOUDY 0
AVERAGE RH (PERCENT) 36
WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM 3 MIXED PRECIP 0
HEAVY RAIN 0 RAIN 0
LIGHT RAIN 4 FREEZING RAIN 0
LT FREEZING RAIN 0 HAIL 0
HEAVY SNOW 0 SNOW 0
LIGHT SNOW 0 SLEET 0
FOG 4 FOG W/VIS <= 1/4 MILE 2
HAZE 2
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
October 3 to October 9 - This week in Denver weather history
The first half of October historically is quiet for the most part but there have been years with plenty of excitement. We have seen damaging tornadoes and winds and of course significant snowstorms.
From the National Weather Service:
3
In 1875…very dense haze hid the mountains from view as observed from the city.
In 1933…rainfall of just 0.01 inch was the only precipitation of the month. This was the second driest October on record.
In 1954…the low temperature cooled to only 60 degrees…the all-time record high minimum for the month October.
3-4
In 1969…the first snowfall of the season totaled 16.0 inches at Stapleton International Airport. There was a thunder snow shower on the evening of the 3rd…but otherwise little wind with the storm. The greatest snow depth on the ground was 8 inches due to melting. Heavy wet snow accumulated on trees…which were still in full leaf…and caused widespread damage from broken limbs and downed utility lines.
3-5
In 1984…the remnants of Pacific Hurricane Polo produced heavy rain over northeastern Colorado. Most locations received between 1.00 to 2.50 inches of rain…but 3.45 inches fell in Littleton. Rainfall totaled 1.73 inches at Stapleton International Airport…where north winds gusted to 24 mph.
4
In 1912…sustained south winds to 55 mph with gusts to 60 mph raised the temperature to a high of 83 degrees… The warmest temperature of the month that year.
In 1924…west winds were sustained to 46 mph with gusts to 50 mph in the city. The apparent Bora winds cooled the temperature to a high of 57 degrees from a high of 70 degrees on the 3rd.
In 2004…several small tornadoes touched down near Brighton… Barr Lake…and Hudson in Adams and southern Weld counties. Most of these caused no damage. However…a small tornado 5 miles southeast of Brighton caused extensive damage to a recreational vehicle and severely damaged a barn. The barn was torn from its foundation…and the roof was thrown 100 feet. Four llamas in the barn were injured when it collapsed.
4-5
In 1997…unusually warm weather resulted in two temperature records. High temperature of 87 degrees on the 4th exceeded the old record set in 1922 by one degree. High temperature of 86 degrees on the 5th equaled the record set in 1990 and previous years.
October is here and it may bring Denver's first taste of snow and freezing temperatures for the season. (iStockphoto / johnnyscriv)
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. Certainly given our recent trend of well-above normal temperatures many are hoping for some relief.
The month actually has our second highest amount of sunshine with 72 percent with September having the most with 74 percent. Interestingly enough, the month following, November, is one of the lowest sunshine months with only 64 percent.
Typically October brings our first real taste of winter with the first freeze on average coming on the 7th of the month and the first snow on the 15th of the month.
You can get all the details including a look back at historical October weather and a look ahead at what October 2010 is expected to bring in our complete preview here.
For the fourth time this month Denver set (or tied) a record high temperature.
Mother Nature obviously hasn’t gotten the message that it is now September and fall is here. Once again Denver broke a record high temperature – the fourth time we have tied or broken a record this month.
According to the National Weather Service the temperature at Denver International Airport reached 92 degrees at 3:55pm. This shatters the old record high for the date of 89 degrees that was set twice, once in 1994 and before than in 1892.
Here in Thornton we were a couple of degrees cooler as we reached a high of 89.7 degrees at 2:41pm.
This is the fourth time this month that we have tied or set a new record high temperature and September 2010 may very well end up as one of the top 10 warmest on record.
As of midnight the average temperature in Denver during September had been 67.0 degrees. If the month were to have ended then we would be in a tie with 1939 for the 7th warmest September on record (see list below).
With temperatures forecast to remain in the mid-80s on Wednesday and around 80 on Thursday it is very possible September 2010 will fit on that top 10 list somewhere. We are certain to far exceed the average September temperature of 62.4 degrees.
For the second Sunday in a row the mercury in Denver reached a record-setting mark.
The Mile High City is on pace to see one of its “top 10 warmest” Septembers on record and that was in full evidence on Sunday. For the third time this month we have tied or broken a record high temperature.
At Denver International Airport today the high temperature reached 90 degrees at 2:54pm thus tying the record for the date set in 1892. This is far above the normal high temperature of 74 degrees for the date.
Here in Thornton we were slightly cooler as we recorded a high temperature of 88.1 degrees at 3:07pm today.
Last Sunday, September 19th, the mercury topped out an amazing 96 degrees. That broke the old record of 93 degrees set in 1980. It was also the hottest temperature ever recorded so late in the year and was the hottest Denver Broncos home game on record.
The recent wildfires have reminded us just how dry Denver has been in recent weeks and the precipitation measurements bear this out. Thus far this month Denver has recorded a mere 0.06 inch of precipitation – far below the average for September of 1.14 inches.
Given that at the current time there is no moisture in the weather forecast through the end of the month, September 2010 may very well go into the record books as one of the top 10 driest Septembers on record. If the month were to end today it would tie for 5th place on the list with 1882 and 1920.
In terms of temperature the month also is threatening top 10 status. As of yesterday the average temperature for the month has been 66.8 degrees. That is more than four degrees above the normal of 62.4 degrees. If the month were to end today that would put the month in a tie for the 9th spot on the top 10 warmest Denver Septembers on record.
September 26 to October 2 - This week in Denver weather history
Denver has been graced with an unusually mild September this year. That however is not always the case and in fact the weather can be downright winterish as we see in our look back at this week in Denver weather history.
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.
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.
