What is the best metaphor for Denver in July, and why is it Hot Pockets?
As we enter the month of July, that sometimes sweet and sour springtime weather makes way for a reasonably stable, warm pattern, kind of like a Hot Pocket. And just like the delicious pastry, July will burn your mouth until you hit that inescapable undercooked spot.
Think of July as a palate cleanser. It’s not spicy hot — it's hot hot. But don’t worry, Mother Nature is coming to our table with something that will help us cool down.
Like most places in the country, July is Denver’s warmest month. It’s also the month when our old friend, the North American monsoon, shows up at our doorstep with water to cool our palates after we stuffed our faces with the all-you-can-eat summer heat.
Let’s take a look at the stats.
Denver's monthly mean temperature for July is 74.2 degrees. The month starts with an average high of 87 degrees and ends with an average high of 90 degrees. The daily average temperatures peak approximately four weeks after the summer solstice.
The warmest July occurred in 2012 when the monthly mean temperature reached 78.9 degrees. The hottest temperature ever recorded in Denver was 105 degrees on July 20, 2005. According to the National Weather Service, there have been 101 triple-digit occurrences in the city since records began in 1872.
And when you bite down into what you think is a fully cooked July, you might come across a cool spot. July's coldest temperature ever recorded in Denver was 42 degrees and occurred on the 31st day of 1873. The coolest July occurred in 1895, with a monthly mean temperature of 67.4 degrees. For low temperatures, July begins with a normal of 57 degrees and finishes with a normal of 60.
Rainfall totals from strong, rain-dumping thunderstorms are still the measure of interest. The mean monthly rainfall for the month is 2.16 inches. There is an average of eight days of measurable rainfall in July, according to the NWS. The wettest July occurred in 1965 when 6.41 inches of rain fell that month.
We typically experience the onset of the North American monsoon during July. It’s a seasonal change in the atmospheric circulation that occurs as the summer sun heats the continental land mass, according to the National Oceanic and Atmospheric Administration.
Severe weather season
Like June, low-level Gulf moisture often finds its way into Eastern Colorado, igniting an afternoon and evening of severe weather ranging from heavy rain to tennis ball-sized hail to tornadoes.
Colorado has entered peak tornado season. The state sees an average of 53 tornadoes per year, according to the National Oceanic and Atmospheric Administration. While June is more active, July sees an average about 11 tornadoes per year.
There have been 2,125 tornado events recorded in Colorado and at least five deaths related to twisters since 1950.
The most tornado-prone county in Colorado — and the entire country — is Weld County, which has seen 268 tornadoes since 1950. The city and county of Denver has seen 16 tornadoes in the same period.
The biggest tornado event that struck Denver was on June 15, 1988. Seven people were injured when an F-3 tornado touched down in the southern part of the city, cutting an erratic path 2.5 miles long. The storm damaged 85 buildings and several cars and uprooted trees.
The injuries were minor, but according to NWS reports, very traumatic for some of those involved. A golfer was thrown 40 feet but was not hurt. A man clinging to a telephone pole was unscathed but lost both of his shoes. A woman holding a baby was sucked through a broken window of a convenience store, but neither the woman nor the baby was hurt.
NWS Tornadic activity doesn't always occur in the usual places in Colorado. Although extremely rare, tornadoes and funnel clouds have been spotted on the Western Slope and in high-altitude areas. There have been three tornado touchdowns in Park County, occurring on June 8, 2014, Aug. 18, 2009, and Aug. 23, 2008. In 2011, a tornado was documented on Mount Evans with an elevation of 11,900 feet. And on June 20, 1975, an F2 tornado touched down in Pitkin County.
Damaging hail is also a concern in July. Storms can produce hailstones up to the diameter of a fully-grown grapefruit. In a typical season, which is from mid-April to mid-August, the Front Range sees about three or four catastrophic hailstorms, according to the Rocky Mountain Insurance Information Association.
Colorado, along with Nebraska and Wyoming, makes up what meteorologists call “hail alley.” The area averages seven to nine hail days per year. According to the National Severe Storms Laboratory, the reason why this area gets so much hail is that the freezing levels (the area of the atmosphere at 32 degrees or less) in the high plains are much closer to the ground than they are at sea level, where hail has plenty of time to melt before reaching the ground.
RMIIA Hail is usually pea-sized to marble-sized, but big thunderstorms can produce big hail. Baseball-sized hail pounded parts of Golden and Lakewood during a record-breaking storm in 2017.
According to the Rocky Mountain Insurance Information Association, Colorado had the second-highest number of hail claims in the US from 2013 to 2015 (182,591), second only to Texas. The costliest hail storm to hit Colorado was on May 8, 2017. The Denver metro area sustained $2.3 billion in insured damage.
Prepare for severe weather
Be prepared for severe weather when it strikes. Follow these tips provided by the Colorado Office of Emergency Management:
- Build an emergency kit and make a family communications plan.
- Identify a safe shelter location – a basement is best, followed by interior rooms on the lowest level of the building away from windows. Mobile homes are often unsafe in a tornado – identify a neighbor's house or public shelter where you can go if a tornado warning is issued.
- Secure outdoor objects that could blow away or cause damage during a storm.
- Unplug any electronic equipment before the storm arrives.
- Obtain a NOAA Weather Radio (link is external) to receive alerts about impending severe weather.
- Sign up for reverse telephone alerts (link is external) for your county, and don't forget to include your cell phone.
- Make sure you have sufficient insurance coverage – including flood insurance, which is separate from your homeowners or renters policy.
- Photograph or take video footage of the contents in your home in case you need to file a claim after a disaster.
- Store copies of your important documents in another location, such as a bank safe deposit box.
