CLIMATE REPORT
NATIONAL WEATHER SERVICE BOULDER, CO                                 
600 AM MST MON JAN 3 2010

................................... 

...THE DENVER CO CLIMATE SUMMARY FOR THE YEAR OF 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 105 07/20/2005 08/08/1878 LOW -29 01/09/1875 HIGHEST 98 08/23 64 34 104 08/01 LOWEST -17 12/09 36 -53 -19 12/15 AVG. MAXIMUM 63.5 64.2 -0.7 64.7 AVG. MINIMUM 36.0 35.8 0.2 35.9 MEAN 49.7 50.1 -0.4 50.3 DAYS MAX >= 90 18 33.1 -15.1 47 DAYS MAX <= 32 26 22.2 3.8 21 DAYS MIN <= 32 161 156.1 4.9 171 DAYS MIN <= 0 7 9.0 -2.0 10 WARMEST YEAR 54.8 1934 COLDEST YEAR 47.6 1911 PRECIPITATION (INCHES) RECORD MAXIMUM 23.31 1967 MINIMUM 7.48 2002 TOTALS 18.12 15.81 2.31 10.21 DAILY AVG. 0.05 0.04 0.01 0.03 DAYS >= .01 94 89.1 4.9 64 DAYS >= .10 45 MM MM 23 DAYS >= .50 12 MM MM 7 DAYS >= 1.00 3 MM MM 3 GREATEST 24 HR. TOTAL 1.64 6/23 1.31 8/6 - 8/7 SNOWFALL (INCHES) RECORDS TOTAL 118.7 1908-1909 24 HR TOTAL SNOW DEPTH MM MM TOTALS 63.7 61.7 2.0 31.9 LIQUID EQUIV 6.37 MM MM 3.19 SINCE 7/1 37.6 25.6 12.0 12.0 LIQUID 7/1 3.76 MM MM 1.20 SNOWDEPTH AVG. MM MM MM MM DAYS >= TRACE 49 MM MM 53 DAYS >= 1.0 19 17.9 1.1 14 GREATEST SNOW DEPTH 7 03/27 5 01/01 24 HR TOTAL 13.3 10/28 TO 10/29 MM 3.9 12/8 TO 12/9 DEGREE_DAYS HEATING TOTAL 7/08 - 6/09 5994 6128 -134 6056 SINCE 7/1 2739 2486 253 2367 COOLING TOTAL 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 9.7 9.9 RESULTANT WIND SPEED/DIRECTION 2/206 2/211 HIGHEST WIND SPEED/DIRECTION 53/260 06/26 46/360 05/02 HIGHEST GUST SPEED/DIRECTION 68/270 06/26 61/180 05/22 POSSIBLE SUNSHINE (PERCENT) 62 69 -7 75 NUMBER OF DAYS FAIR 71 74 NUMBER OF DAYS PC 219 237 NUMBER OF DAYS CLOUDY 75 55 AVERAGE RH (PERCENT) 55 51 WEATHER CONDITIONS. NUMBER OF DAYS WITH THUNDERSTORM 66 MIXED PRECIP 1 HEAVY RAIN 17 RAIN 29 LIGHT RAIN 82 FREEZING RAIN 0 LT FREEZING RAIN 4 HAIL 5 HEAVY SNOW 6 SNOW 19 LIGHT SNOW 51 SLEET 0 FOG 120 FOG W/VIS <= 1/4 MILE 41 HAZE 71 - INDICATES NEGATIVE NUMBERS. R INDICATES RECORD WAS SET OR TIED. MM INDICATES DATA IS MISSING. T INDICATES TRACE AMOUNT. $$ ...2009 WAS WETTER THAN NORMAL BUT THE AVERAGE TEMPERATURE WAS NEAR NORMAL... THE ANNUAL PRECIPITATION WAS WELCOMED BY DENVERITES AS THE YEAR FINISHED WITH A TOTAL OF 18.12 INCHES WHICH WAS 2.31 INCHES ABOVE THE NORM OF 15.81. THE GREATEST 24 HOUR PRECIPITATION WAS 1.64 INCHES ON JUNE 23RD. THERE WAS A TOTAL OF 94 DAYS WITH MEASURABLE LIQUID (5 ABOVE NORMAL)...12 DAYS GREATER THAN 0.5 INCH AND EVEN 3 DAYS GREATER THAN 1.0 INCH. THE YEAR WITH THE WETTEST TOTAL WAS 1967 WITH 23.31 INCHES. SNOWFALL WAS ALSO ABOVE NORMAL FOR BOTH THE CALENDAR YEAR WITH A 63.7 INCHES COMPARED TO THE 61.7 INCH NORMAL. FOR THE PERIOD JULY THROUGH DECEMBER...HALF OF THE 2009-2010 SNOW SEASON...THE TOTAL ACCUMULATED WAS 37.6 INCHES WHICH IS 2.0 INCHES ABOVE NORMAL. THERE WERE 49 DAYS WITH SNOW GREATER THAN A TRACE AND 19 DAYS WITH THE WHITE STUFF EXCEEDING AN INCH. GREATEST 24 HOUR SNOWFALL OCCURRED BETWEEN OCTOBER 28TH AND 29TH WITH A TOTAL OF 13.3 INCHES. THE HEAVIEST SNOW STORM WAS OBSERVED BETWEEN OCTOBER 27TH THROUGH THE 29TH WITH 15.3 INCHES OF SNOW. THE MOST SNOWFALL RECORDED IN DENVER WAS IN THE 1908- 1909 SNOW SEASON WITH 118.7 INCHES. IN 2008...THE TOTAL FOR THE CALENDAR YEAR WAS ONLY 31.9 INCHES. TEMPERATURES FINISHED PRETTY MUCH NEAR NORMAL. THE NORM IS 50.1 DEGREES AND THE YEAR FINISHED WITH 49.7 DEGREES...ONLY 0.4 DEGREE BELOW NORMAL. THIS YEAR THERE WERE 18 DAYS THAT EQUALED OR EXCEEDED THE 90 DEGREE MARK COMPARED TO 2008 WITH 47 DAYS. THERE WERE NO MERCURY READINGS THAT REACHED THE 100 DEGREE MARK. 171 DAYS RECORDED LOW TEMPERATURES AT OR BELOW FREEZING WHICH IS 15 ABOVE NORMAL. TEMPERATURES RANGED FROM A HIGH OF 98 DEGREES ON AUGUST 23RD DOWN TO A NON-RECORD LOW OF -17 RECORDED ON DECEMBER 9TH. THERE WERE 32 DAYS WHEN THE HIGH TEMPERATURE DID NOT GET ABOVE FREEZING. 1
9 RECORDS WERE SET OR TIED DURING 2009. 533 COOLING DEGREE DAYS WERE MEASURED WHICH WAS 163 BELOW NORMAL WHILE IN THE HEATING DEGREE CATEGORY...THE SEASON RUNS FROM JULY 2008 THROUGH JUNE 2009...THE TOTAL WAS 5616 DAYS WHICH WAS 512 BELOW NORMAL. SIXTY SIX THUNDERSTORMS WERE OBSERVED AT THE DENVER INTERNATIONAL AIRPORT (DIA). TWO THUNDERSTORMS PRODUCED FUNNEL CLOUDS NEAR THE AIRPORT AND 5 STORMS PRODUCED HAIL...MOSTLY IN THE PEA SIZE CATEGORY. 82 DAYS HAD LIGHT RAIN WHILE 17 DAYS RECORD HEAVY RAIN. OUT OF 120 FOG DAYS...41 RECORDED DENSE FOG WITH VISIBILITIES OF 1/4 MILE OR LESS. THERE WERE 71 FAIR/CLEAR DAYS...219 PARTLY CLOUDY DAYS AND 75 DAY WITH CLOUDS COVERING THE ENTIRE SKY. 51 DAYS HAD LIGHT SNOW WITH 6 REGISTERING HEAVY SNOW. THE PEAK WIND DURING 2009 WAS 68 MPH FROM A WESTERLY DIRECTION ON JUNE 26TH.
TO SEE A BRIEF MONTHLY SUMMARY FOR EACH OF THE MONTHS OF 2009...CLICK HERE ALL IN ALL...2009 WAS NOT A BAD YEAR FOR THE DENVER METRO AREA. WEATHER WISE...2009...COMPARED TO ANNUAL AVERAGES...IT HAD SLIGHTLY BELOW NORMAL TEMPERATURE AND GREATLY APPRECIATED ABOVE NORMAL PRECIPITATION. BENTON


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