Category Archives: Climatology

Thornton’s September weather preview: Usually a calm, pleasant month

Following an August that was unseasonably warm and dry, 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.

Denver hits 100 degrees for the first time of the year, breaks record high for August 18

Record High Temperature

For the fourth time this month, the Mile High City set or tied a high temperature record and also recorded its first mercury reading of 100 degrees in almost a year.

As measured at Denver International Airport, Denver’s official high temperature today hit 100 degrees. This easily breaks the record high for August 18 of 98 degrees set in 2013. This was the first time Denver hit 100 degrees this year. The last time was on September 2, 2019. This also marks the 58th time Denver has seen a reading of 90 degrees or higher this year.

Here in Thornton, we matched Denver’s reading of 100 degrees and it was the second time this year we hit the mark. The first came exactly one month ago on July 18.

Looking into the history books, Denver has recorded 100 degree or higher temperatures 93 times since 1872. With the warming climate though, we have been averaging two 100 degree days per year over the past 30 years.

Many are comparing this year to the scorching hot summer of 2012. That year we saw 73 days of 90 degree or warmer temperatures and thirteen of those with 100 degree readings or higher. We also tied Denver’s all-time high of 105 degrees twice that year.

Denver sets a new record high temperature for August 17

Record High Temperature

Continuing our seemingly unending string of hotter than normal temperatures, today’s readings hit record-setting territory.

As measured at Denver International Airport, the Mile High City’s temperature topped out at 98 degrees today. That breaks the previous record high for August 17 of 97 degrees set in 2013.

Thornton was just a touch cooler with a high of 96.6 degrees.

This is the third high temperature record set or tied in Denver thus far this month. On August 9th the record high was broken and on August 11th it was tied.

Denver sets record high temperature for August 9

Record High Temperature

Our long, hot summer continues and today Denver set a record high temperature.

As measured at Denver International Airport, the Mile High City’s mercury topped out at 99 degrees today. That breaks the old record high temperature for August 9 of 98 degrees set in 2012.

Thornton lucked out and was actually a slight bit cooler today with a high of 97.4 degrees.

Denver ties record high temperature for July 18, Thornton hits 100 degrees

Record High Temperature

Another toasty day today, and one that was record-setting.

As measured at Denver International Airport, Denver’s official high temperature today topped out at 99 degrees. That ties the record high for July 18 set last year and in previous years.

Here in Thornton, we were actually warmer by one degree hitting 100.1 degrees. This is our first 100 degree reading of the year.

Denver sees first 90 degree day of the year, sets record high temp for May 19

Record High Temperature

We knew getting our first 90 degree reading of the year was a possibility today and sure enough, we did. Not only that, Denver also set a record high temperature for the date.

As measured at Denver International Airport, the high temperature in the Mile High City hit 92 degrees today. That tops the old record high temperature for May 19 of 90 degrees set in 2009.

Thornton held itself just a bit cooler with a high of 91 degrees.

On average, Denver sees its first 90 degree day on June 10 so we are a few weeks ahead of schedule.

Thornton’s 2019 / 2020 snow season comes in as second snowiest of past 13 years

Thornton, Colorado's 2019 / 2020 snow season report and totals. Click for larger view. (ThorntonWeather.com)
Thornton, Colorado’s 2019 / 2020 snow season report and totals. Click for larger view. (ThorntonWeather.com)

As it appears we are done with the white stuff for the season, we can now report a finally tally for snow.

Thornton’s season recorded 84.3 inches, the second most since Thornton Weather came online in 2006. Only the 2015 / 2016 season had more (85.7 inches).

The total is most notable because we never did receive a truly big storm, just a number of respectable ones. The totals were helped by big months in October, November and February which overcame a very dry December and January.

Officially, as measured at Denver International Airport, only 57.6 inches was recorded. This was a mere 1/2 inch more than Denver’s long term seasonal average of 57.1 inches.

Those numbers continue to reflect the problem with having the Mile High City’s official weather station located out at the airport where it is in a totally different microclimate whose conditions don’t reflect what the metro area really sees.

For comparison, the site at Stapleton closest to where Denver’s records were recorded for 57 years before the move to DIA saw 71.4 inches of snow this season.

March 2020 weather recap: Temperatures and precipitation come in above normal

The month of March was a relatively quiet one for the most part. We didn’t see any particularly notable extremes and only one significant snowstorm.

The month started out on the cool side and we received our first snow of the month on the 2nd. We then put together a stretch lasting two weeks with largely calm and dry conditions.

The 19th offered up a return to wintry conditions as after some rain early in the day, a transition to snow began and we received a healthy 7.5 inches of the white stuff.

Mostly dry conditions were the feature of the last 10 days of the month with a few days seeing temps above normal but most coming in below.

Thornton’s overall average temperature for the month came in at 42.2 degrees. This was a good bit above Denver’s March average of 40.4 degrees. Out at Denver International Airport where the Mile High City’s official records are kept, the reading nearly matched ours at 42.5 degrees.

Our warmest day on the 11th delivered a high of 71.1 degrees while our coldest, the 21st, saw a morning low of 14.2 degrees. Denver’s maximum reading of 68 degrees came on four different days. Their coldest of 11 degrees came on the 21st.

In terms of precipitation, Denver averages 0.92 inches in March. Thornton bested that easily with 1.56 inches and Denver did as well with 1.26 inches.

Both Thornton and Denver fell short of March’s average monthly snowfall of 10.7 inches. Thornton came closest with 9.3 inches while at the airport 7.5 inches was measured.

Click here to view Thornton’s March 2020 climate report.

Thornton, Colorado's March 2020 temperature summary. (ThorntonWeather.com)
Thornton, Colorado’s March 2020 temperature summary. (ThorntonWeather.com)
Thornton, Colorado's March 2020 precipitation summary. (ThorntonWeather.com)
Thornton, Colorado’s March 2020 precipitation summary. (ThorntonWeather.com)

Thornton’s April 2020 weather preview: Winter, spring and summer all in one month

Thornton's April weather previewApril marks a transition between winter and summer for most of the country but for Denver it is especially true as we can see a stunning variety of weather.

The proverbial April showers are certainly a possibility for Denver. Snow? Tornadoes? Thunderstorms? You bet – all can happen!

For good measure throw in a chance for hail and even dust storms and April gives every type of weather condition you could like – or hate.