Category Archives: Thornton Weather

Throwback Thursday: Images of the June 15, 1988, tornado outbreak in Denver.

June 15, 1988 - Tornadoes strike Denver, Colorado. (ThorntonWeather.com)
June 15, 1988 – Tornadoes strike Denver, Colorado. (ThorntonWeather.com)

This was a fun find! I was going through old family photos and came across these images of a famous – and destructive – Denver weather event.

At that time, I was staying with my sister at her house on Fox Street near 96th Ave in Thornton. The weather was clearly getting spicy and where she lived provided clear views to the south and southeast.

We were amazed to watch multiple twisters strike in and around the city, me grabbing pictures with my old 35mm Canon AE-1 Program.

The National Weather Service history for the event describes “several” tornadoes. The most powerful was an F3 that struck in south Denver and was on the ground for 25 minutes. That twister alone damaged 85 buildings and many vehicles. Miraculously, no serious injuries or deaths were reported.

Below see more pictures I took that day and you can read the official account from the NWS and watch some archived news stories from the day.

From the National Weather Service:

In 1988…several tornadoes developed across metro Denver. One tornado touched down just northeast of the rocky mountain arsenal. The twister moved very slowly and did no damage…except to demolish a small electrical substation… Even though it was on the ground for nearly 30 minutes. Later…another tornado was sighted east of Brighton about 2 miles north of Barr Lake. An f2 tornado cut a swath through northeast Denver. The main path went through a thickly wooded area for about 6 blocks and uprooted about 500 city owned trees…many of them large elms 75 to 100 years old. Hundreds of privately owned trees were also sucked from the ground by the slow moving twister…which was filmed by a news team in a helicopter as it uprooted trees. The replacement cost to the city owned trees was estimated at 1.5 million dollars. The twister did little damage to buildings. Some homes suffered roof and chimney damage…a gas main was ruptured…and some cars were damaged by falling trees. The uprooted trees also caused curb and sidewalk damage and cut some electrical wires. The funnel cloud passed close to Stapleton International Airport. Aircraft operations were shut down…and the tower was evacuated. The tornado was on the ground for almost 25 minutes. An f3 tornado cut an erratic path through south Denver for about 25 minutes…causing extensive damage in at least 3 areas. The twister damaged about 85 buildings… 20 severely; the total loss was estimated at 5 to 10 million dollars. Many cars were severely damaged; at least 15 vehicles were overturned. One trailer was lifted onto the top of a building that had just been unroofed; numerous antique cars inside the building were damaged. A Ford Bronco was blown over a church…and landed 100 yards away. A metal storage shed was deposited far above the ground in some power lines. The tornado uprooted many trees on a golf course. No one was seriously hurt…although seven people suffered minor injuries from flying debris. A golfer was thrown 40 feet…but was not hurt; a man clinging to a telephone pole was unscathed…but lost both shoes…a sock…and buttons off his shirt. A woman holding a baby was sucked through a broken convenience store window… But was unhurt. A dog…tethered to the ground by its leash… Was suspended in the air by the twister. Uprooted trees crushed cars and damaged curbs and sidewalks. People in downtown Denver could see three tornadoes occurring simultaneously. Hail as large as 1 3/8 inches in diameter fell in extreme southeast Aurora.

September 2025 Weather Recap: Temps near normal, precipitation well above average

Thornton, Colorado's September 2025 temperature summary. (ThorntonWeather.com)
Thornton, Colorado’s September 2025 temperature summary. (ThorntonWeather.com)

Thornton was finally able to break out of the hot, dry weather pattern of recent months and see things get a bit more normal. September historically is one of our most pleasant months and 2025 largely held true to that.

We did start out pretty mild and precipitation was meager for the first half of the month. Finally, on the 13th, we began to see things cool down and then on the 16th got a nice shot of rain (0.61”).

The rest of the month offered mild but comfortable temperatures. A strong trough on the 23rd cooled us considerably with that day offering high temperatures nearly 20 degrees below normal. It also brought a very healthy shot of rain (1.21″).

In the end, the average temperature for the month of September ended up very close to average. Thornton’s average for the month was 64.6 degrees. This was just a hair higher than our 19 year running average for the month of 64.3 degrees. Our maximum temperature for the month was 92 degrees and came on the 10th. Our coolest reading of 42.3 degrees was on the 25th.

For Denver, at Denver International Airport where the Mile High City’s official measurements are taken, temperatures were on par with ours. They reported an average for the month of 64.7 degrees. This was close to their long term average for September of 64.8 degrees.

In terms of precipitation, Thornton saw a notable 2.09 inches for the month. This was far above our 19-year running average of 1.51 inches for September. This was the fourth wettest September over that period.

The Mile High City was quite a bit drier with 1.35 inches recorded in their rain bucket. It was, however, above their long term average for the month of 1.09 inches.

No snow was recorded in Thornton or Denver for the month.

Click here to view Thornton’s complete September 2025 climate summary report.

Thornton, Colorado's September 2025 precipitation summary. (ThorntonWeather.com)
Thornton, Colorado’s September 2025 precipitation summary. (ThorntonWeather.com)

Thornton’s October 2025 preview: Generally calm conditions with our first freeze and snow

The month of October.

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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September 2025 top shots: Monthly photo slideshow

The month of September is typically one of the more pleasant months in Colorado.  Temperatures are usually comfortable and there is not normally a lot of weather drama.  That however does not mean there aren’t plenty of photo opportunities.

Wildlife is still quite active along the Front Range and flowers will hold on to their petals for at least the first part of the month.  Then of course there is the weather which you never know what to expect.  Thunderstorms, heavy rain, and even snow are a possibility.

  • Slideshow updated September 30, 2025
  • 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.

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!

Leaf peeping 2025: When and where to see the fall colors

Rocky Mountain National Park is a prime spot for viewing the fall foliage. (Tony's Takes)
Rocky Mountain National Park is a prime spot for viewing the fall foliage. (Tony’s Takes)

This time of year many folks start thinking about heading to the hills west of Denver in search of gold – fall foliage gold.

Where to go?  Below are five of ThorntonWeather.com’s favorite ones near Denver – plus a few further out and some bonus ideas.  After that, we will tell you where you can find a great website that provides regular updates on viewing conditions.

I-70 Corridor – If you’re looking for the easiest route, then this one is for you.  Simply head west on I-70 about 110 miles to Avon.  Between Vail and Avon, both sides of I-70 are lined beautifully with aspen.

Rocky Mountain National Park – One of the most popular summer destinations in the state is of course also a prime spot to view aspen in all their glory.  Once in the park head toward Bear Lake.  Glacier Gorge Junction provides a beautiful spot and you of course also get to enjoy all the splendor that Rocky Mountain National Park has to offer.  Extend your viewing by taking Trail Ridge Road all the way through to the west side of the park and the Grand Lake and Granby area.

Peak to Peak Highway – This little road trip can be a dual purpose trip – gambling and fall foliage viewing!  Take U.S. 6 through Clear Creek Canyon and then 119 through Blackhawk and Central City.  You can of course stop there if your wallet is fat enough and donate some money to the casinos.  From there continue on 119 toward Nederland.  Take highway 72 toward Ward and Allenspark.  There you will find more golden aspen than you can imagine, all with the Continental Divide nearby.

Colorado Fall Foliage - Average Date of Peak Aspen Colors. Click for larger view. (ThorntonWeather.com)
Colorado Fall Foliage – Average Date of Peak Aspen Colors. Click for larger view. (ThorntonWeather.com)

Poudre Valley Canyon –  Heading north on I-25 take Colorado 14 west and into Poudre Canyon and Roosevelt National Forest.  As you continue west you will come very near timberline as you come to Cameron Pass.  Amazing views abound!

Guanella Pass – This is a nice, relatively short drive from Denver.  From C470 take 85 through Bailey and Conifer, a nice drive unto itself.  When you come to the town of Grant, take the Guanella Pass Scenic and Historic Byway north to Georgetown.  The air is pretty thin along the way as you climb in excess of 11,500 views through the Pike and Arapahoe National Forests.

A couple other possibilities further from the Front Range:

Leadville / Aspen – From Denver take I-70 west to Copper Mountain and then Colorado 91 south over Freemont Pass to Leadville. Along the way there are plenty of viewing opportunities and Leadville is a nice little town to make a stop. From here you can take Highway 24 north back through Minturn and Vail. To extend the drive, take Highway 24 south to Colorado 82 and head toward Aspen. You can stop by the Maroon Bells in White River National Forest to view some of the most photographed mountains in Colorado.

Cottonwood Pass – From Denver take Highway 285 to Buena Vista. Head west on Main Street for seven miles then west on County Road 344 / Colorado 82. From there you start the climb up Cottonwood Pass with absolutely stunning views from the top. If you are up for it, you can continue down the west side of the pass into the Taylor Park area.

Honorable mentions worth considering:

  • Boreas Pass between Breckenridge and Como (County Road 10)
  • Kenosha Pass on Highway 285 between Bailey and Fairplay
  • Independence Pass (Colorado 82 between Aspen and Twin Lakes)
  • Colorado 103 from Evergreen to Echo Lake. Throw in a drive up Mount Evans for a bonus.

If you do head out, be sure to send us your pictures for inclusion in our monthly photo slideshows!

For more information:

August 2025 weather recap: Another month with warm temps, below normal precipitation

Thornton, Colorado temperature summary for August 2025. (ThorntonWeather.com)
Thornton, Colorado temperature summary for August 2025. (ThorntonWeather.com)

A recurring theme from most of 2025 for August. Thornton once again saw temperatures above normal and precipitation below, something that has happened far too often this year.

Above normal temperatures dominated the first three weeks of the month. Mercury readings in the 90s were common with only three days being below that mark. Precipitation was absolutely scarce with a mere 0.01 inches being recorded during the first 21 days of the month.

Thankfully, Mother Nature took mercy on us for the last 10 days of August. We saw temperatures cool a good bit with every day seeing below average readings. While precipitation wasn’t great, she also was kind enough to finally give us a couple days with much-needed rain.

Temperatures in Thornton came in at an average of 72.6 degrees for the month. This was a good bit above the 19-year running average for August of 71.8 degrees. It was also the sixth month in a row for Thornton with above average temperatures.

Out at DIA where Denver’s official records are taken, it was a good bit warmer. The Mile High City saw an average of 73.8 degrees for August 2025. This was above their long term average for August of 72.9 degrees.

In terms of precipitation, Thornton ended up with 0.51 inches in the bucket. Virtually all of that fell in the last seven days of the month. It was well below our running August average of 1.20 inches.

For Denver, they saw two days with thunderstorms that dumped a great deal of rain on the airport, storms that missed us. As a result, their rain total for the month was a surprising 4.12 inches. This was well above their long term average for August of 1.58 inches.

Click here to view Thornton’s complete August 2025 climate summary report.

Thornton, Colorado precipitation summary for August 2025. (ThorntonWeather.com)
Thornton, Colorado precipitation summary for August 2025. (ThorntonWeather.com)

Thornton’s September 2025 preview: Usually one of the most pleasant months of the year

Thornton's September weather preview.
Thornton’s September weather preview.

Following an August that was unseasonably warm, we find ourselves heading into September hoping for relief.  The month can bring plenty of rain and even our first snow of the season but more often than not, it is one of the most pleasant along the Colorado Front Range.

As temperatures start to drop, September usually reminds us that summer is at an end and fall is now here. Sunshine is predominant though as the month actually has the highest percentage of sun out of any month. Sunny days and clear, cool nights are the standard weather pattern for the month.

The month can bring extremes however.  We will of course forever remember 2013’s devastating floods brought on by record-setting rain.  Longtime residents might remember September 1971 which brought over 17 inches of snowfall.

Get a complete look at September’s weather and more details as to what we can expect this year here.

August 2025 top shots: Monthly photo slideshow

August 4, 2025 - Smoke from wildfires on the Western Slope arrives on the Front Range. (David Canfield)
August 4, 2025 – Smoke from wildfires on the Western Slope arrives on the Front Range. (David Canfield)

As the calendar turns to August, the summertime heat begins to fade and that makes it easier to get out and enjoy all of the outdoor activities Colorado has to offer.  From a walk in a park to afternoon thunderstorms to an abundance of wildlife, photo opportunities abound as is seen in our slideshow.

Our monsoon season typically arrives about now and that means better chances for moisture.  However with limited instability, the intensity of storms are more sedate.  That doesn’t mean however that the weather is any less photographic.

  • Slideshow updated August 31, 2025

By the end of the month some of our seasonal feathered friends will be looking to leave the state giving our last chance to see them till spring.  Larger mammals are gearing up for the rut (mating season) and that can make for some intense scenes.

Showcasing images captured by ThorntonWeather.com readers as well as some of our own, our monthly slideshow covers the entire gamut of weather and nature related imagery. Sunsets, sunrises, wildlife and of course every type of weather condition are vividly depicted.

To learn more about how to send your photo to us for inclusion in the slideshow, see below the slideshow.


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!

Thornton’s August 2025 preview: Temps begin to cool, severe weather eases

Thornton's August Weather Preview
Thornton’s August Weather Preview

As summer vacations wind down and families prepare to send their kids back to school in August, Colorado weather also starts to settle down. The chances for severe weather decrease markedly during August and by the end of the month daytime temperatures are dropping quite a bit as well.

Find out more about what lies ahead with Thornton’s August weather here.

July 2025 weather recap: Above average temps, below average precipitation

Thornton, Colorado's July 2025 Temperature Summary. (ThorntonWeather.com)
Thornton, Colorado’s July 2025 Temperature Summary. (ThorntonWeather.com)

If you were thinking the past month was hot and dry, you would certainly be correct. Thornton’s July saw average mercury readings a good bit above average and precipitation well below average.

Looking back, probably one of the most notable things about the month was that there wasn’t a whole lot notable. We saw nothing significant in the way of severe weather and while it was hot, it wasn’t overly extreme. It was noteworthy that the last two weeks of the month were quite dry yielding only 0.03” of rain over the period.

Thornton’s average temperature for the month came in at 75.2 degrees. This was a good bit above our running 18 year average for July of 73.9 degrees. Temperatures ranged from a high of 102.1 degrees on the 9th down to 55.3 degrees on the 11th.

Out at DIA where the Mile High City’s official measurements are taken, similar readings were seen. Denver saw an average temperature for the month of 75.1 degrees. This actually matched their long-term average for July.

In terms of precipitation, Thornton saw 0.63 inches fall in its rain bucket. The majority of that fell during the first half of the month. That is well below our running average for July of 1.88 inches.

For Denver, they recorded similar precipitation with 0.64 inches being recorded. This was well below their July average of 2.14 inches.

Click here to view Thornton’s complete July 2025 climate summary report.

Thornton, Colorado's July 2025 Precipitation Summary. (ThorntonWeather.com)
Thornton, Colorado’s July 2025 Precipitation Summary. (ThorntonWeather.com)