Denver records its wettest 4th of July ever; Record draws attention to climate data problems

According to the National Weather Service, record-setting rain fell in Denver on the 4th of July.  But is it accurate to say that? (ThorntonWeather.com)
According to the National Weather Service, record-setting rain fell in Denver on the 4th of July. But is it accurate to say that? (ThorntonWeather.com)

Heavy rain showers put a damper on a lot of Independence Day celebrations yesterday.  Thunderstorms moved across the Front Range dumping rain and hail across northeastern Colorado with enough rain falling to set a record for the 4th of July.

At Denver International Airport (DIA), 1.84 inches of rain was recorded.  This easily eclipses the old 4th of July record dating back to 1909 when 1.44 inches fell. 

Here in Thornton we weren’t nearly as wet having recorded 0.81 inches for the storms that moved through.  Some of the other rainfall totals from across the metro area:

  • Arvada: 0.89 inch
  • Aurora: 0.86 inch
  • Broomfield: 0.57 inch
  • Castle Rock: 0.71 inch
  • Conifer: 0.31 inch
  • Centennial:  1.01 inches
  • Denver (north): 0.51 inch
  • Littleton: 0.26 inch
  • Longmont: 0.43 inch

Denver, we have a problem

The rain totals at DIA were impressive however comparing them to the other amounts recorded at stations across the metro area once again highlights problems with Denver’s climate records.  As we have discussed before on Examiner.com, moving Denver’s official monitoring station to DIA is forever altering climate records

The rain yesterday was heavy in places but nowhere in the central Denver area measured anywhere near the amount DIA recorded (see map below).   When the National Weather Service (NWS) announces a “record” like the rain yesterday, it is comparing the measurements at DIA to historical records taken at the old Stapleton International Airport from 1950 to 1995 and downtown from 1871 to 1949. 

Is it accurate to claim a weather record when the station doing the recording is 12 miles away from where historical records were made?  Of course not and this is a problem.   

Last year the NWS partially conceded to the problem and installed an official monitoring station in Denver City Park.  Denver’s official records however still come from the station at DIA. 

The National Weather Service either needs to start recording Denver’s official statistics from the new station or it needs to quit comparing data from DIA to that recorded before the move in 1995. 

Denver’s climate records are forever being altered and the public is being misled. 

The National Weather Service recorded 1.84 inches of rain at the official monitoring station at DIA on Sunday, July 4, 2010.  No other station in the area recorded near this amount though. (MesoWest / ThorntonWeather.com)

July 4 to July 10 – This week in Denver weather history

July 4 to July 10 – This week in Denver weather history
July 4 to July 10 – This week in Denver weather history

As we pointed out in our July weather preview, the month is not only our hottest but it is also the stormiest.  Scorching summer heat is certainly evident when we look back at this week in Denver weather history.  Perhaps more notable is the severe weather we have seen with everything from hail, damaging wind, dangerous lightning and deadly flooding having occurred.

29-15

In 2000…the 29th marked the beginning of a near record hot streak for metro Denver.  The high temperatures…as recorded at Denver International Airport…exceeded the 90 degree mark for 17 consecutive days from June 29th through July 15th. The record of 24 consecutive 90 degree or above days was set from July 13th through August 5th…2008.

1-18 

In 1874…a streak of 18 consecutive days of 90 degrees tied for second with another streak that was later set in the summer of 1901. The record of 24 consecutive days was established in the summer of 2008.

4

In 1874…the temperature reached a high of 102 degrees in downtown Denver.  Large forest fires in the mountains from the west-northwest to the south filled the atmosphere over the city with dense smoke.
 
In 1885…a thunderstorm produced sustained winds to 44 mph with gusts to 60 mph.  A circus tent was tattered by the strong winds.
 
In 1900…a thunderstorm produced northwest winds sustained to 42 mph with gusts to 51 mph…but only 0.05 inch of rain.
 
In 1903…the all time lowest temperature ever recorded in July…42 degrees…occurred. The temperature also occurred on July 31…1873.
 
In 1910…thunderstorm winds were sustained to 42 mph from the southwest.
 
In 1922…thunderstorm winds were sustained to 37 mph with gusts to 48 mph.
 
In 1956…a thunderstorm wind gust to 54 mph was recorded at Stapleton Airport.
 
In 1964…several men were knocked down by a bolt of lightning while playing golf in south metro Denver.  They got up and ran for cover when one of them was struck by a second bolt. He suffered burns and shock.
 
In 1987…a weak tornado was observed for 6 minutes…7 miles northeast of Watkins.  Hail 3/4 to 1 1/4 inches in diameter fell in southeast Aurora.
 
In 1988…lightning struck a group of people at the Jefferson County fairgrounds.  A 42-year-old woman was seriously injured and was hospitalized for 3 days.  Four other people sustained minor injuries.
 
In 1993…strong northwest winds uprooted several trees across metro Denver.  Wind gusts to 64 mph were reported at Erie north of Denver.  A west wind gust to 43 mph was recorded at Stapleton International Airport.
 
In 1995…lightning struck and injured two people standing in a field in Arvada.
 
In 1998…heavy thunderstorm rain…up to 2.75 inches…and marble size hail combined to flood local roads and fields near Roggen.
 
In 2002…heavy thunderstorm rain in the Hayman Fire burn area caused flash flooding.  In Jefferson County…gulch road was washed out.  In Douglas County…high water washed out some forest access roads as well…generally to the east of a line extending from signal butte to Deckers.

Continue reading July 4 to July 10 – This week in Denver weather history

A hot Saturday but much cooler weather on tap for Independence Day

Thornton's weather forecast for the Independence Day weekend.
Thornton's weather forecast for the Independence Day weekend as of Saturday morning. Follow the link in the story for the latest forecast.

The holiday weekend is upon us and the weather looks to be a bit of a mixed bag. Plenty of heat will be on tap Saturday but the weather changes considerably on Independence Day, threatening those fireworks shows.

For Saturday, we have a day much like we saw yesterday. Partly cloudy skies will be overhead with high temperatures reaching the low to mid-90’s. This afternoon brings with it a slight chance for isolated thunderstorm and shower activity. Right now, we aren’t expecting any of those storms to turn severe in the metro area.

Independence Day is of course the big day as we celebrate the 234th birthday of our Great Nation. An upper level trough will be moving through late tonight and through Monday and with it comes cooler temperatures and increased chances of moisture.

Highs on Sunday look to be considerably cooler and only in the low to mid-70’s under mostly cloudy skies. The concern right now is the increased chance for rain showers that is expected to arrive in the afternoon and threatens to put a damper on fireworks shows. This will bear watching so check back tomorrow for an update.

On Monday we start to rebound a bit from the cooler weather but temperatures will remain below normal. Highs will be in the low to mid-80’s under partly cloudy skies and a slight chance for thunderstorms.

The balance of next week looks to continue a cooler-than-normal trend with temperatures hovering around 80 Tuesday through Thursday.

June 27 to July 3 – This week in Denver weather history

June 27 to July 3 - This week in Denver weather history
June 27 to July 3 - This week in Denver weather history

Closing out June and entering July our look back at this week in Denver weather history is marked by severe weather and scorching heat.  Damaging hail to dangerous lightning are two common occurrences as is record-setting heat waves.

From the National Weather Service:

21-3 

In 2002…the maximum temperature in Denver equaled or exceeded 90 degrees for 13 consecutive days…equaling the 5th longest such streak on record.  The record of 18 consecutive days was set during the summer of 1901.

26-27

In 1965…wind gusts to 38 mph were recorded in downtown Boulder…causing widespread minor damage.  A microburst wind gust to 41 mph was recorded at Stapleton International Airport.

27

In 1873…Pikes Peak was hidden from view by smoke from forest fires in the mountains to the southwest of the city.
 
In 1927…the temperature cooled to a low of only 72 degrees… The all-time record high minimum for the month.
 
In 1980…lightning injured 4 people on a baseball diamond in Broomfield.  The bolt seriously injured the pitcher while also striking (out) the batter…catcher and second baseman.
 
In 1987…a microburst wind gust to 53 mph was recorded at Stapleton International Airport.
 
In 1990…the temperature reached a high of 102 degrees… Setting a new record maximum for the date.
 
In 1993…thunderstorm winds gusted to 60 mph across parts of metro Denver.  A wind gust to 50 mph blew over a 30-foot canvas tent at an amusement park southeast of Denver. Fifteen people…mostly children…were injured.  Microburst wind gusts to 33 mph were recorded at Stapleton International Airport.
 
In 2002…heavy rain…up to 3/4 inch…fell across sections of the Hayman burn area near Cheeseman Reservoir.  Several forest service roads were washed out and many culverts were plugged by debris.
 
In 2004…heavy rain producing thunderstorms caused rock and mud slides across the overland fire burn area in Jamestown. An estimated 50 tons of sand…dirt…rock…and ash slid into town…filling a culvert under main street.  The slide covered 150 to 225 feet of Main Street.  The flood was produced by half an inch of rain in 30 minutes.  A deluge of very heavy rainfall from nearly stationary thunderstorms caused flooding and flash flooding problems over parts of Jefferson and Douglas counties.  An automated rain gage in Golden measured 3.60 inches of rainfall in one hour.  Numerous homes were flooded in Golden…including one that was 146 years old. The home was listed as a complete loss.  State Highway 93 had to be closed from the Pine Ridge subdivision to the Golden Gate Canyon Road.   At the height of the storm…about 4 feet of water covered State Highway 93 through Golden… Forcing its temporary closure.  Several intersections were also flooded and impassable.  Rock and mud slides were reported in Golden Gate Canyon State Park.  At the Deer Creek Golf Course at Colorado 470 and Kipling…the greens were completely inundated by floodwaters.  Some backyards near the golf course were partially washed out.  In Douglas County…water up to a foot deep covered the roadways in Roxborough State Park.  The Waterton Canyon Road also had to be closed due to high water.

Continue reading June 27 to July 3 – This week in Denver weather history

Tropical Storm Alex threatens Gulf of Mexico oil spill cleanup

Satellite image of Tropical Storm Alex as it prepares to cross the Yucatan Peninsula. (NOAA / Google Earth)  Click the image for a complete slideshow of the storm and its forecast path.
Satellite image of Tropical Storm Alex as it prepares to cross the Yucatan Peninsula. (NOAA / Google Earth) Click the image for a complete slideshow of the storm and its forecast path.

The first named storm of the 2010 hurricane season is being watched closely by not only areas at threat from landfall but also those working to clean up the Gulf oil spill. Tropical Storm Alex continued to move to the northwest where it threatens to find warmer water and become a hurricane.

The National Hurricane Center (NHC) places the center of Alex at the current time 75 miles east of Belize City. The storm is packing winds of 45 mph and moving to the west-northwest at 9mph.

On its current path, Alex will reach the coast of Belize and the Yucatan Peninsula late today and move across the peninsula on Sunday. By Sunday night or early Monday morning, it will have transited land and emerge in the Bay of Campeche.

Get all the latest on Tropical Storm Alex including amazing satellite animation video, forecasts and more from the Natural Disasters Examiner.

June 20 to June 26 – This week in Denver weather history

June 20 to June 26 - This week in Denver weather history
June 20 to June 26 - This week in Denver weather history

Late June weather is usually relatively calm but when it turns severe, it can do so in spades.  Hail, flooding rains, tornadoes and more are not unusual.  This week in Denver weather history we see plenty of each of those including a hail storm in 1993 that damaged dozens of planes at Denver International Airport. 

19-21

In 1875…smoke from several large forest fires in the mountains was visible from the city on each of these days.

20

In 1888…northwest winds were sustained to 44 mph.
 
In 1956…a microburst caused a brief wind gust to 58 mph at Stapleton Airport.
 
In 1964…hail up to 1 inch in diameter was reported 1 mile north of Stapleton International Airport.  A 3 minute hail storm at both Stapleton International Airport and Lowry Field piled small hail to one half inch deep.
 
In 1967…a strong thunderstorm dumped 1.95 inches of rain in less than an hour at Stapleton International Airport and produced a wind gust to 54 mph.  The storm caused some flooding in east Denver and Aurora.  There was widespread flooding to streets…basements…and store buildings and automobiles.  Hail stones to 3/4 inch in diameter were measured at Buckley Field in Aurora.  A tornado touched down just south of Littleton…damaging a barn and killing several head of cattle.
 
In 1985…a wind gust to 61 mph was reported at Golden Gate Canyon in the foothills west of Denver.
 
In 1986…a man was killed by lightning at Highlands Ranch south of Denver.
 
In 1987…several tornadoes were sighted across metro Denver.  A tornado touched down briefly 5 miles west of Parker.  A tornado was sighted just north of Chatfield Reservoir.  A tornado just northwest of Watkins was on the ground for 15 minutes.  A tornado near Barr Lake was taped by a television news crew.  It had a double vortex and was on the ground for about 10 minutes.  In addition to the 4 tornadoes…severe thunderstorms dumped large hail across metro Denver.  One inch hail was reported in southeast Aurora; 3/4 inch hail fell at the Denver technology center…Buckley Field…and Franktown.
 
In 1992…several short-lived tornadoes occurred in the vicinity of Barr Lake.  No injuries or damages were reported.  A water spout was sighted over the southern end of Barr Lake.  Funnel clouds were also sighted on the grounds of the rocky mountain arsenal by national weather service observers at Stapleton International Airport.
 
In 1994…hail up to dime size covered I-25 south of Denver and near Sedalia.  Heavy rain caused local flooding on the interstate highway.
 
In 1996…strong thunderstorm winds downed several large tree limbs in Boulder on the University of Colorado campus.  A stop light in the city was also blown down.
 
In 1999…lightning sparked an oil tank fire near Brighton.
 
In 2001…large hail driven by strong thunderstorm winds raked Denver international and Front Range airports.  Wind gusting to 54 mph along with hail as large 2 inches in diameter punched at least 14 thousand holes and cracks in the flat roofs of several buildings at Denver International Airport. In addition…93 planes and hundreds of cars were damaged. About 100 flights had to be cancelled…stranding 1500 travelers.  The airport was completely shut down for about 20 minutes.  The storm also damaged a ground avoidance radar used to track planes on the ground to prevent collisions. Damage was estimated at 10 million dollars…not counting the damage to the 93 airliners.  The storm moved south and struck Watkins with hail as large as 2 1/2 inches in diameter and winds gusting to 60 mph.  A least 30 private planes at Front Range airport were destroyed.  The radome protecting the national weather service doppler radar…which was tracking the storm…also sustained damage.  The large hail…damaging winds…and heavy rain pummeled a mobile home park near Watkins.  In the park…52 mobile homes…14 recreational vehicles…3 homes…and a commercial building were damaged.  Siding was riddled with holes and windows were broken.  Vehicles sustained extensive damage and car windows were shattered.  A handful of people were treated for minor cuts and bruises.  The strong winds also flipped a tractor trailer along I-70 near Watkins.  The storm caused power outages…which affected about 1200 residents. Excluding the damage at Denver International Airport…damage estimates totaled 49 million dollars…making the storm the costliest in the last 3 years and the 10th costliest since 1984.  A small tornado touched down just east of Brighton… But did no damage.  Hail as large as 2 inches in diameter fell near Fort Lupton with 3/4 inch hail measured in Bennett.  Precipitation from the storm totaled only 0.23 inch at Denver International Airport.
 
Continue reading June 20 to June 26 – This week in Denver weather history

Thornton Veterans Memorial ready to start construction on first phase

The Thornton Veterans Memorial is ready to start construction on the first phase! Be sure to contribute to the effort!
The Thornton Veterans Memorial is ready to start construction on the first phase! Be sure to contribute to the effort!

A dedicated group of volunteers at the Thornton Veterans memorial Foundation announced that they will be starting construction on the first phase of the city’s veterans memorial.  This is an exciting milestone for all veterans – past, present and future – who deserve a memorial in their honor.

The first phase of construction will include the center pentagon, educational signage and flag poles.  Further, all paver bricks that have been purchased will be engraved and laid in the memorial and its walkways at this time. 

If you haven’t placed your order for a paver brick engraved with the name of a veteran you wish to honor or some other appropriate message, NOW IS THE TIME.  Orders for engraved paver bricks to be included in this initial phase of construction MUST be received by the Thornton Veterans Memorial by no later than Tuesday, June 29th. 

Please visit the foundation’s online store TODAY and place your order!  Don’t miss out on this opportunity to honor our nation’s veterans!

Tony Hake, owner and operator of ThorntonWeather.com, has personally donated over $2,000 to the memorial and encourages all area residents, civic organizations and businesses to contribute.  ThorntonWeather.com is entirely free for everyone and Hake has asked that donations to the veterans memorial be made instead of paying for the information on this site. 

Please consider making a tax deductible contribution to the memorial to help us ensure the men and women who have sacrificed for us have a place of honor.  Visit the Thornton Veterans Memorial website’s main page and click on the Uncle Sam image to give to the memorial today!

Al Gore decries press censorship of oil spill, blocks press from own events

Al Gore laments a lack of press coverage of the Gulf oil spill disaster but bans the press from his own events. (Dan Spisak)
Al Gore laments a lack of press coverage of the Gulf oil spill disaster but bans the press from his own events. (Dan Spisak)

In a new blog posting on his website, former Vice President Al Gore said access by the press covering the BP oil spill in the Gulf of Mexico is a ‘de facto form of censorship.’ Many however have been quick to seize on the fact that Gore himself bans press coverage of his own events.

The Nobel Laureate was writing a response to a report that a Times-Picayune photographer was not allowed to take photos of the expanding oil slick. Gore said, “This behavior is completely unacceptable. Access by reporters should be as unfettered as possible. This de facto form of censorship needs to stop.”

Bloggers and online news outlets were quick to seize on the apparent hypocrisy in Gore’s statement. The highly influential Drudge Report pointed to Gore’s posting followed by stories from 2008 and 2009 when the press was banned from covering the former vice president’s speeches.

There is more to this story including the errors that have been discovered in Gore’s books and movies and his recent personal life problems.  Get all the details from the Climate Change Examiner.

NCAR scientists determine planes can punch holes in clouds

An example of a hole-punch cloud over Alabama. (Alan Sealls, WKRG-TV / NCAR)
An example of a hole-punch cloud over Alabama. (Alan Sealls, WKRG-TV / NCAR)

Mysterious, almost UFO-looking, clouds have fascinated viewers from the ground for decades. Now, scientists at the National Center for Atmospheric Research (NCAR) in Boulder have determined that planes can ‘punch holes’ in clouds and perform the equivalent of cloud seeding.

Andrew Heymsfield, a scientist at NCAR, said that given the right conditions, planes climbing or descending can cause the atmospheric phenomena known as hole-punch, or canal clouds. When they do, they create unusual cloud formations and can cause rain and snow to develop.

Scientists have long speculated about the cause of the unusual ‘holes’ in the clouds and had attributed them to various aviation-related causes, none of which were conclusive.

The scientists at NCAR determined that water droplets at 5 degrees Fahrenheit (-15 degrees Celsius) are the key factor. When a plane flies through these droplets, the air behind it is cooled and the droplets freeze and fall toward the Earth.

There's more to this story on Examiner.com!Get the rest of this story including more photos and video explaining the phenomena at the Denver Weather Examiner!

Funnel cloud over two-mile-high Leadville raises eyebrows

A 'cold air funnel' was spotted over Leadville, Colorado on Sunday morning. (NWS Pueblo)  See amazing video of the funnel cloud below.
A 'cold air funnel' was spotted over Leadville, Colorado on Sunday morning. (NWS Pueblo)

At an altitude nearly two miles high, one would not expect a funnel cloud to appear in the sky over a town like Leadville, Colorado. On Sunday however, Mother Nature treated visitors and residents to a rare ‘cold air funnel’ over the town high in Colorado’s Rocky Mountains.

At approximately 10:30 a.m. on Sunday, the funnel was spotted over Leadville where it continued to rotate for nearly 20 minutes, according to observers. The funnel never touched down, thus never becoming a tornado, but it serves as a reminder that twisters can occur just about anywhere on earth.

Funnel clouds and tornadoes typically need four conditions to form – Shear, Lift, Instability and Moisture (SLIM as famed storm chaser Roger Hill calls it). With a cold air funnel, those conditions also exist, although they aren’t associated with a supercell thunderstorm like is seen on the plains.

According to the National Weather Service’s Pueblo office, a cold low pressure system over northwestern Colorado provided the instability part of the equation. Strong upper level winds over the southwestern part of the state and slower winds over the northwest provided shear. The difference in lower and upper level temperatures and a passing thunderstorm provided the lift and moisture for the funnel.

One Denver-area television station is incorrectly reporting on its website that “Leadville was never in any danger because he says cold-air funnels do not turn into tornadoes.”

This is wholly inaccurate. While cold air funnels do not typically touch down, they can reach the ground and as the National Weather Service states, they “can bring damage in a small area.”

Weather, natural disasters & climate news and information.