THE FOLLOWING TABLES GIVE A MONTH BY MONTH BREAKDOWN OF WEATHER IN 2013 AT THE SIOUX FALLS AIRPORT...
MONTH AVERAGE DEPARTURE EXTREMES MONTHLY MAX MIN MONTHLY FROM NORM HIGH LOW RECORDS JANUARY 26.9 8.0 17.5 PLUS 0.9 46 -9 FEBRUARY 30.3 12.7 21.5 0 44 -8 MARCH 36.7 18.4 27.5 MINUS 5.4 66 6 APRIL 49.5 29.1 39.3 MINUS 7.1 85 15 2ND COLDEST 3RD SNOWIEST MAY 67.3 47.0 57.2 MINUS 0.8 94 24 3RD SNOWIEST JUNE 77.0 56.9 66.9 MINUS 0.9 88 42 JULY 82.7 61.6 72.2 MINUS 0.8 92 44 9TH DRIEST AUGUST 81.7 61.6 71.7 PLUS 1.0 93 49 SEPTEMBER 78.6 55.3 66.9 PLUS 5.6 91 35 7TH WARMEST OCTOBER 57.9 37.4 47.6 MINUS 0.3 80 24 NOVEMBER 43.7 20.0 31.8 MINUS 0.8 60 -1 DECEMBER 21.1 2.2 11.6 MINUS 7.6 48 -19 2013 54.5 34.2 44.3 MINUS 1.5 94 -19
DEPARTURE DEPARTURE MAX WIND GUST MONTH FROM NORM SNOWFALL FROM NORM DIRECTION/MPH/DATE JANUARY 0.41 MINUS 0.15 2.1 MINUS 5.6 NW 51 ON 19TH FEBRUARY 0.94 PLUS 0.34 9.6 PLUS 2.7 NW 48 ON 2ND MARCH 0.88 MINUS 0.88 1.5 MINUS 6.9 NW 46 ON 18TH APRIL 3.13 PLUS 0.12 14.8 PLUS 10.2 NE 51 ON 9TH MAY 6.95 PLUS 3.55 1.5 PLUS 1.5 S 47 ON 19TH JUNE 4.28 PLUS 0.36 S 43 ON 14TH JULY 0.60 MINUS 2.49 S 38 ON 12TH AUGUST 3.23 PLUS 0.18 N 45 ON 31ST SEPTEMBER 0.77 MINUS 2.00 S 43 ON 26TH OCTOBER 3.01 PLUS 0.84 0.4 MINUS 0.9 S 46 ON 11TH NOVEMBER 0.46 MINUS 0.90 7.5 PLUS 0.1 S 46 ON 3RD DECEMBER 1.13 PLUS 0.44 12.6 PLUS 4.4 NW 44 ON 28TH 2013 25.79 MINUS 0.59 50.0 PLUS 5.5 NE 51 APR 9TH
Sioux Falls weather for the year 2013 had below normal temperatures and slightly below normal precipitation. The biggest event of the year was the severe ice storm on the morning of April 9th... accompanied by lightning and thunder...heavy rainfall and wind gusts of 40 to 50 mph. One half inch of rain fell...all of it freezing with temperatures of 30 or 31 degrees...between 5 and 7 am CDT. A peak wind gust of 51 mph from the northeast occurred at 650 am CDT...the highest gust of the year. Ice and wind combined to produce considerable damage to trees and private property. Numerous tree limbs were felled and in some cases whole trees toppled over. The cleanup of the branches by the city was named Operation Timber Strike. The operation took over two months and millions of dollars to clean up.
The average temperature for the year was 44.3 degrees which is 1.5 degrees below normal. This is the coolest year since 1997 when the average temperature was 43.9 degrees...and 6.2 degrees cooler than 2012 at 50.5 degrees. The average high for the year was 54.5 degrees and the average low was 34.2 degrees. There were 11 days of 90 degrees or more including four in a row from August 26th through the 29th. 94 degrees on May 14th was the hottest day of the year. The year had a total of 80 days with highs of 32 degrees or less...and 185 days with lows of 32 degrees or less. A total of 25 days had low temperatures of zero degrees or colder. The coldest day of the year occurred on December 7th at 19 degrees below zero.
Precipitation for the year was 25.79 inches which was 0.59 inches below normal...and 8.45 inches more than the previous year when 17.34 inches fell. May was the wettest month with 6.95 inches and the wettest day occurred on October 14th with 2.27 inches. There was a total of 108 days of measurable precipitation...a hundredth of an inch or more...a total of 46 days with a tenth of an inch or more...14 days with a half inch or more and 7 days with an inch or more.
The year started off with near to slightly above normal temperatures for the months of January and February. January had only 2.1 inches of snow...increasing to 9.6 inches in February. A total of 6.3 inches fell during a storm on February 21st and 22nd.
Spring was delayed by much below normal temperatures during the months of March and April. The average temperature for this two month period was 33.3 degrees which ties for 6th coldest in 1975. The coldest March/April period occurred in 1899 with an average temperature of 30.4 degrees. With an average temperature of 39.3 degrees...April 2013 is the second coldest on record. April 1950 was the coldest at 37.8 degrees. Notable cool spells occurred between March 16th and 26th when the average temperature of 22.8 degrees was 12.3 degrees below normal...and from April 9th through the 25th with an average temperature of 32.8 degrees…which was 14.4 degrees below normal. Beginning on April 25th temperatures began a warm-up with highs in the 70s or better the last five days of the month. 85 degrees was the warmest which occurred on the 28th. A record low was broken on April 20th with a minimum temperature of 16 degrees. Record low maximum temperatures were set on April 18th with 32 degrees and April 23rd at 34 degrees. March precipitation was half of normal with much of it falling as 0.76 inches of rain on the 8th and 9th. April had near normal precipitation with much of it falling...just over two inches...between the 9th and 11th. Ice...sleet and snow fell on the 9th with a total of 1.42 inches liquid equivalent. Snowfall for the three day period totaled 7.2 inches. Additional snows of 2.9 inches fell on the 18th and 4.6 inches on the 22nd. The total snowfall for the month of April was 14.8 inches...making it the third snowiest on record. The snowiest April on record occurred in 1983 with 18.4 inches while the second snowiest April occurred in 1994 with 14.9 inches.
The month of May started out cool with a record daily snowfall of 1.5 inches on the 1st...making it the third snowiest May on record. Two inches of snow fell during May 1943...and three inches fell in 1944. The 1.5 inches of snow was the first measurable snowfall in the month of May since May 2nd 1976 when a tenth of an inch fell. Precipitation for the month ended up nearly double the normal at 6.95 inches. A total of 4.1 inches of rain fell over a three day period from the 25th through the 27th. Continuous lightning and very heavy rain fell on the night of the 25th and 26th with a total of 2.85 inches at the airport. Much of southern and western Sioux Falls measured from four to five plus inches. The very heavy rain brought flash flooding to the city. The temperature averaged 57.2 degrees for the month...nearly a degree below normal. The hottest day of the month and year occurred on the 14th at 94 degrees. The high of 40 degrees on the 4th broke the record for coldest maximum temperature.
The heaviest rain of the summer months of June...July and August occurred on June 8th with a daily record of 1.87 inches. A bit of an oddity is that no lightning and thunder occurred...just a steady rain that began at 538 am CDT and continued through the day and evening. Dry conditions developed during late June into August with only 1.12 inches total from June 25th through August 9th. The 9th driest July on record occurred in 2013 with only 0.60 inches of rain. The biggest rain of the month was 0.28 inches on the 20th. August saw a bit more rain with 1.90 inches on the 10th and 11th. The strongest thunderstorm of the year developed after dark on the last day of August. Continuous and spectacular lightning accompanied the storm...along with heavy rain...hail and high winds. The southern portion of the city received damage from the hail up to baseball in size and high winds. Rainfall for the month of August totaled 3.23 inches. The average temperature for the summer was 70.3 degrees...just a bit below the average of 70.5 degrees. The average high for the summer was 80.5 degrees and the average low 60 degrees. A daily record low of 44 degrees was set on July 28th...and a daily record high minimum temperature of 75 degrees was set on august 25th.
Warm and dry weather prevailed during September...making area farmers happy after a late planting season. Rainfall for the month was only 0.77 inches...two inches below normal. The average temperature for the month was 78.6 degrees...or 5.6 degrees above normal.
October and November were both slightly below normal in temperature. The first freeze of the season occurred October 13th with a morning low of 28 degrees...and the first measurable snowfall of four tenths of an inch fell on October 22nd. A daily record rainfall of 2.27 inches occurred on October 14th. This is the fourth wettest October day with 4.54 inches the wettest on record. A daily record snowfall of 5.7 inches fell on November 5th. November 6th through the end of the month was dry with only 0.05 inches of precipitation and 1.8 inches of snow. Arctic high pressure moved into the area on the 22nd bringing the first subzero chill of the season and a record barometric pressure for the month of November of 30.96 inches on the 23rd.
December was cold and snowy as a series of arctic fronts moved into the Northern Plains. The average temperature for the month was 11.6 degrees which was 7.6 degrees below normal. This is the coldest December since 2000 when the average temperature was only 7.6 degrees. The coldest day of the year occurred on the 7th when the mercury fell to 19 below zero. A record low maximum was tied on the 6th with a high of only 3 below zero. A total of 13 days during the month had lows of zero degrees or colder and six days of 10 below or colder. Snow fell on several days but was generally light with amounts of two inches or less. The exception was a 5.4 inch snowfall on the 4th for a storm total of 6.2 inches including the evening snow that began on the 3rd. The six inches of snow depth on the 5th was the greatest of the year.