Colorado natives and those that have lived here long enough know that Denver and Colorado weather changes considerably throughout the year. The month of May almost seems to pack four seasons of weather conditions into 31 days. You name it, it can happen.
This being the latter half of spring, May does mean warm temperatures. Temperatures in the 80’s are common and reaching into the 90’s is not unheard of. The normal highs start out at 65 on the first but by the end of the month that climbs to 76. The record high for the month was recorded on May 26, 1942 of 95 degrees.
Despite the snowstorm that struck on March 23rd and 24th and the rain that fell beforehand, the National Weather Service says Denver's March precipitation was below normal.
According to the Denver / Boulder office of the National Weather Service, Denver’s March weather was warmer and drier than normal. The latest climate summary from the service would seem to contradict what Denver residents actually experienced, at least in terms of precipitation.
The report starts with a seemingly contradictory statement saying, “Denver’s March 2010 finished with below normal liquid moisture in spite of finishing above normal in the snowfall category.”
According to the report, Denver recorded 0.80 inch of precipitation, well below the normal of 1.28 inches. Most of that occurred in conjunction with the snowstorm on the 23rd of the month when the official measuring station at Denver International Airport (DIA) reported 0.61 inch of precipitation. By contrast, ThorntonWeather.com recorded 1.42 inches of precipitation from that storm alone and 1.90 inches for the month.
Overall for the season, Denver has recorded 58.8 inches of snow which is 7.5 inches above the average snowfall up to this point. Denver’s snow season runs from July through June and we average 61.7 inches over that period so for 2010 we are quickly approaching a ‘normal’ year.
The average temperature as recorded at DIA was 41.0 degrees which was 1.4 degrees above the normal of 39.6 degrees. Temperatures for the month ranged from a high of 82 degrees on the 30th down to a low of 13 degrees on the 20th. The 82 degree high temperature on the 30th broke the record for that date of 81 degrees set way back in 1879.
Controversy once again surrounds measurements in latest report
The March 2010 climate summary once again highlights the problem. Comparison of temperature records for DIA versus areas closer to historical monitoring locations continue to show discrepancies. Standing out even more are precipitation records that are curious at best, ridiculous at worst given the wet snowstorm that struck on the 23rd and 24th.
The Denver Weather Examiner is in the process of updating our previous investigation and will have an updated report soon. In the meantime, you may wish to look at the results of the investigation we conducted last year.
April 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.
The good news is that sunshine and warmer temperatures are usually in abundance as the normal highs during the month move up from 57 degrees on the first to 65 degrees on the 30th. It is not unusual to have a number of days well into the 70’s and the low 80’s. We also see the normal lows move above freezing from 30 degrees at the start of the month to 39 degrees by the end. Temperature extremes can hit both ends of the spectrum with a record low of 2 degrees below zero on April 2, 1975 and a record high of 90 degrees on April 30, 1992.
March in Denver typically means frequent and rapid weather changes. The days grow longer and we start enjoying more sunshine and sometimes summer-like weather. However, on occasion arctic air masses can still force their way south into Colorado dropping temperatures quickly and markedly.
These changes are due to March’s “in between” status – elements during the month have much in common with winter and spring. In addition to arctic fronts, Pacific storms frequently move across Colorado from the west and warm moist air streams up from the Gulf of Mexico northeastward into the state. When these cold fronts collide with the warmer air masses the result can be some crazy weather.
February comes and serves as a bit of a month of transition between winter and spring. Average temperatures start to climb and things are generally pretty quiet.
However, it is still winter and below freezing temperatures at night still remain the norm. February is not typically a snowy month – in fact only the 6th snowiest – with an average of 6.3 inches. In terms of severe weather, the month joins September and October as being the quietest for Denver.
As we say though, it is a month of transition and as such extremes can and have occurred in the past. From severe cold and snow to beautiful spring-like days we can see it all. Oftentimes the month can lull us into a false sense of spring when the snowiest month – March – has yet to come.
Severe cold weather has enveloped the northern half of the globe from the United States to Britain to China. Across the continents, many places are reporting record setting temperatures and lives have been lost due to the Arctic chill.
The eastern half of the United States saw cold, Arctic air pulled down from the north plunging temperatures below freezing in normally mild places as far south as Florida. The widespread cold gripped most of the nation east of the Rocky Mountains to the Gulf of Mexico and the Atlantic Seaboard.
Across the Midwest, temperatures plunged to well below freezing as parts of Iowa recorded temperatures as low as -15 degrees. Jeff Johnson, National Weather Service meteorologist, told the Des Moines Register, “”We’re a solid 30 degrees below normal.” Minneapolis, Minnesota and Chicago, Illinois were seeing wind chills below 0 degrees Tuesday morning.
In Miami, residents accustomed to short sleeve shirts and shorts bundled up as temperatures dropped to freezing. Further north in the state, Orlando saw a low temperature of 21 degrees.
The National Weather Service issued hard freeze warnings across parts of Mississippi, Alabama, Georgia and Florida as the cold threatened the agriculture industry in those states. Freeze watches in Tennessee highlighted the severe cold and came on the heels of reports that four people have died in that state from the cold.
For the second time in the past three months, Denver has experienced monthly average temperatures in the ‘top 10 coldest’ category. In October, the Mile High City saw its second coldest October on record since record keeping began in 1882. Now Denver has just wrapped up its seventh coldest December in history.
Denver’s average December 2009 temperature was 24.1 degrees – a chilly 6.2 degrees below the normal average of 30.3 degrees. That puts the month into the books as the seventh coldest December on record (image right). Thornton was just a touch colder having recorded an average temperature of 23.8 degrees.
Temperatures during the month ranged from a high temperature of 59 degrees on the 1st down to a low of -17 on the 9th. Overall, the majority of days during the month saw below normal temperatures.
In terms of snowfall, the month did finish above average but not in record setting territory. The National Weather Service recorded 11.1 inches of snowfall at the official monitoring station at Denver International Airport. This was 2.4 inches above the average of 8.7 inches for December. In Thornton, we received a bit more snow than DIA. 15.3 inches was recorded at ThorntonWeather.com of which the single biggest even was the pre-Christmas storm which dumped 7.5 inches.
The snow we did receive however was rather dry and as such we finished the month below normal for precipitation. DIA recorded 0.45 inch of precipitation which is 0.18 inch below normal. Here again, because of the additional snowfall, Thornton fared a bit better with 0.5 inch of precipitation.
CLIMATE REPORT
NATIONAL WEATHER SERVICE BOULDER, CO
510 PM MST SAT JAN 2 2010
...................................
...THE DENVER CO CLIMATE SUMMARY FOR THE MONTH OF DECEMBER 2009...
CLIMATE NORMAL PERIOD 1971 TO 2000
CLIMATE RECORD PERIOD 1872 TO 2009
WEATHER OBSERVED NORMAL DEPART LAST YEAR'S
VALUE DATE(S) VALUE FROM VALUE DATE(S)
NORMAL
................................................................
TEMPERATURE (F)
RECORD
HIGH 79 12/05/1939
LOW -25 12/22/1990
12/24/1876
HIGHEST 59 12/21 79 -20 69 12/02
12/01
LOWEST -17 12/09 -25 8 -19 12/15
AVG. MAXIMUM 36.4 44.1 -7.7 41.0
AVG. MINIMUM 11.9 16.4 -4.5 12.3
MEAN 24.1 30.3 -6.2 26.6
DAYS MAX >= 90 0 0.0 0.0 0
DAYS MAX <= 32 15 5.3 9.7 10
DAYS MIN <= 32 31 29.2 1.8 30
DAYS MIN <= 0 6 2.8 3.2 6
PRECIPITATION (INCHES)
RECORD
MAXIMUM 5.21 1913
MINIMUM 0.00 1881
TOTALS 0.45 0.63 -0.18 0.24
DAILY AVG. 0.01 0.02 -0.01 0.01
DAYS >= .01 7 5.3 1.7 6
DAYS >= .10 2 MM MM 0
DAYS >= .50 0 MM MM 0
DAYS >= 1.00 0 MM MM 0
GREATEST
24 HR. TOTAL 0.20 12/22 TO 12/23 0.10 12/13 TO 12/14
SNOWFALL (INCHES)
RECORDS
TOTAL 57.4 1913 SNOWIEST DENVER MONTH SINCE 1881
TOTALS 11.1 8.7 7.1
DEGREE_DAYS
HEATING TOTAL 1260 1078 182 1179
SINCE 7/1 2739 2486 253 2367
COOLING TOTAL 0 0 0 0
SINCE 1/1 533 696 -163 825
FREEZE DATES
RECORD
EARLIEST 09/08/1962
LATEST 06/08/2007
EARLIEST 10/07
LATEST 05/05
.................................................................
WIND (MPH)
AVERAGE WIND SPEED 8.8
RESULTANT WIND SPEED/DIRECTION 3/217
HIGHEST WIND SPEED/DIRECTION 43/220 DATE 12/13
HIGHEST GUST SPEED/DIRECTION 49/220 DATE 12/13
SKY COVER
POSSIBLE SUNSHINE (PERCENT) MM *SUNSHINE DATA N/A EFFECTIVE 10/1
NUMBER OF DAYS FAIR 4
NUMBER OF DAYS PC 21
NUMBER OF DAYS CLOUDY 6
AVERAGE RH (PERCENT) 61
WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM 0 MIXED PRECIP 0
HEAVY RAIN 0 RAIN 0
LIGHT RAIN 0 FREEZING RAIN 0
LT FREEZING RAIN 0 HAIL 0
HEAVY SNOW 0 SNOW 2
LIGHT SNOW 10 SLEET 0
FOG 11 FOG W/VIS <= 1/4 MILE 1
HAZE 7
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
Denver now as an official weather monitoring station closer to downtown but some say this doesn't solve the problem of the city's climate records being altered. (Examiner.com)
It only took 14 years but Denver finally has an official monitoring station near downtown again. The new station amongst the greens of City Park Golf Course finally gives residents of Denver a place to see what the weather is doing closer to home.
With the opening of Denver International Airport in 1995, the National Weather Service moved its station to the new airport. That distance of 12 miles from the old Stapleton facility to DIA confounded citizens, television meteorologists and weather enthusiasts as they all noted that no one lives out at the airport and the conditions reported there do not reflect what is happening closer to town.
Recognizing the problem, a public-private partnership came together to do what they could to rectify the problem. The City and County of Denver, the Denver Museum of Nature and Science, the National Weather Service and NOAA, 7News Chief Meteorologist Mike Nelson and Colorado State Climatologist Nolan Doesken identified a site for the new station.
Eclar Fence and Mercury Electric donated the infrastructure for the new site. Weather equipment manufacturer Vaisala donated the weather monitoring hardware and services, estimated at up to $60,000.
You can view the data from the new station right here on ThorntonWeather.com. Visit our ‘Station Historical Data’ page and select ‘Denver (City Park)’ from the dropdown box.
Certainly there is little doubt the new station will provide area residents the ability to view conditions closer to where they actually live. The new station will not however address the very real problem of Denver’s climate records having been altered since the move to DIA. The National Weather Service has said the official records for Denver will still come out of DIA and as such many believe those records come with an asterisk.
October 2009 in Denver was the second coldest and fifth snowiest October on record.
Most of the month of October was cooler than normal in the Mile High City and now that the month is over we see just how cold it was. Denver finished October 2009 with an average temperature more than 8 degrees below normal and had 9 inches more snow than what is normal for the month.
October 2009’s 42.9 degree average makes it the second coldest since record keeping began in 1873 – 136 years ago! re in Thornton we were actually slightly cooler with an average temperature of 42.0 degrees. Only October 1969 was colder as that year Denver had an average temperature of a chilly 39 degrees. He
Across the board temperatures for the month were well below normal. The average daily high temperature of 54.7 degrees was 11.3 degrees below the normal of 66.0 degrees. Low temperatures were similarly well below normal with an average of 31.1 degrees – 4.8 degrees below the normal of 35.9.
Thornton was warmer for daytime highs than the Denver official temperatures as we averaged 55.6 degrees. In terms of low temperatures, we were cooler having averaged 30.7 degrees.
November is Denver's second snowiest month. What else can we expect?
Typically November is a quiet weather month with plenty of nice, fall days but it can also turn wet with plenty of snow and moisture. Just like Forest Gump’s proverbial box of chocolates, you never quite know what you are going to get.
Looking into the weather history books, we see that November is actually Denver’s second snowiest month, second only to March (April is third). Historically we average 10.7 inches of snow during the month.
In 1994, November was the snowiest month of that year with 16.9 inches – over 12 inches of which fell within a 12 hour period on the 13th and 14th. In 1991 we saw 29.6 inches of snow (the 2nd snowiest November) and the following year in 1992 we had 20.1 inches of snow (the 8th snowiest November). Those examples though pale in comparison to the snowiest November on record which was in 1946 when a whopping 42.6 inches of snow fell!
It isn’t always that snowy though. November 2002 was at the time the 16th month in a row with below normal precipitation and the calendar year of 2002 marked the driest in Denver weather history. This pattern of below normal precipitation continued for 19 months through February 2003. Since 1882, one year (1949) recorded no snow, six more recorded only a trace of snow and four had less than one inch of snow.
Colorado natives and those that have lived here long enough know that Denver and Colorado weather changes considerably throughout the year. The month of May almost seems to pack four seasons of weather conditions into 31 days. You name it, it can happen.
