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Riverton Climate Summary Banner

...Highlights of 2017...

  • Annual: 2nd wettest year on record (1918-2017) with 15.86 inches of precipitation which is 188 percent of normal,  2nd snowiest year on record with 71.1 inches of snowfall which is 192 percent of normal., Annual average temperature was slightly below normal.
  • Seasonal:  Wettest first four months of the year (January though April) with a combined 9.23 inches of precipitation, shattering the old record of 7.20 inches set in 2016. 
  • Monthly Temperatures: 8th coldest January, 3rd warmest March (tie) 10th warmest November on record.
  • Monthly Precipitation: 2nd wettest January, 5th wettest February, 3rd wettest March, wettest April, 10th wettest August on record. 
  • Monthly Snowfall: Snowiest January, 6th snowiest February, 6th snowiest April on record.


Temperature Banner   

Element Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
 Average High  14.0 35.1 55.8 55.8 66.9 81.0 90.2 84.4 70.8 57.8 48.1 32.4 57.7
 Mean High (1981-2010 Normals) 31.0 37.4 49.6 60.3 69.2 79.4 88.2 86.7 74.9 60.0 43.1 29.5 59.1
 Average Low -6.4  11.4 28.5 32.4 40.1 48.9 56.2 51.2 43.9 28.9 22.5 6.3 30.3
 Mean Low (1981-2010 Normals) 6.2 11.0 22.5 30.6 40.1 48.1 54.0 51.4 41.4 30.0 17.6 5.4 29.9
 Average Temperature  3.8 23.2 42.2 44.1 53.5 64.9 73.2 67.8 57.4 43.4 35.3 19.3 44.0
 Mean Average Temperature (1981-2010 Normals) 18.6 24.2 36.1 45.4 54.6 63.8 71.1 69.0 58.2 45.0 30.3 17.4 44.5
 Departure from Normal  -14.8 -1.0 6.1 -1.3 -1.1 1.1 2.1 -1.2 -0.8 -1.6 5.0 1.9 -0.5
 Rank: Coldest to Warmest
 100 years of record
(P.O.R 12/1918-2017)
8 43 96 48 41 67 80 48 44 27 89 56 59
 
 Highest Daily Maximum  41 56 73 77 84 92 97 93 94 74 63 57 97
 Date of Occurrence  11 22 19 14 13  21 21 5 3 26 2 4 7/21
 Lowest Daily Minimum -33 -11 4 19 32  41 44 45 30 12 12 -22 -33
 Date of Occurrence 6 3 1 5 14,18  13  1 16 27 31 30 24 1/6
 Number of Days with:                          
    Maximum >= 90° 0 0 0 0 0 4 21 8 2 0 0 0 35
    Maximum <= 32° 29 13 0 0  0  0 0 0 0 0 0 13 55
    Minimum <= 32° 31 28 24 13  2  0  0 0 2 25 26 31 182
    Minimum <= 0°  22 6 0 0  0  0  0 0 0 0 0 7 35
 Record Maximum Highs Set or Tied 0 0 2 0  0 0 0 0 0 0 0 1 3
 Record Minimum Highs Set or Tied 0 0 0 0 1 0 1 0 0 0 0 0 2
 Record Minimum Lows Set or Tied 1 0  0  0  0 0  0 0 0 0 0 0 1
 Record Maximum Lows Set or Tied 0 0 3 0 1 0 0 1 2 0 3 0 10
 * Multiple day occurrence

Temperature Ranks and Records:
 

 Daily Records:

 
Record High Temperatures:

 

  March  71 on the 16th, 73 on the 19th (tie).
  December  57 on the 4th (tie).
 
Record Low Maximum Temperatures:  
 
  May: 37 on the 19th.
  July 74 on the 26th (tie).
 

Record Low Temperatures:

  January: -33 on the 6th.
 
Record High Minimum Temperatures:
 
  March: 35 on the 14th (tie), 40 on the 23rd (tie), 43 on the 30th.
  May: 50 on the 7th.
  August: 62 on the 31st.
  September: 63 on the 10th, 55 on the 11th (tie).
  November: 35 on the 17th, 36 on the 23rd, 37 on the 24th. 
 

 

   Coldest Months of January on Record
Rank Year Average Temperature °F
1 1979 -7.3
2 1937 -3.1
3 1930 -1.4
4 1949 -0.4
5 1962 2.0
6 1963 2.8
7 1924 3.2
8 2017 3.8
9 1993, 1932 4.1
 
   Warmest Months of March on Record
Rank Year Average Temperature °F
1 2012 43.9
2 1986 43.2
3 2017 ,2007 42.2
5 1992 40.8
6 1934 40.5
7 1972 39.9
8 1940 39.2
9 2016, 1946 38.9
 
Warmest Months of November on Record
Rank Year Average Temperature °F
1 1949 40.0
2 1954 38.6
3 1999 37.7
4 1927 37.0
5 2008 36.1
6 1926 36.0
7 1995 35.8
8 2016, 1965 35.7
10 2017, 2006 35.3
 

 

 

   Warmest Years on Record (95 Years)
Rank Year Average Temperature °F
1 2012 48.5
2 2006, 1999 47.0
4 1934 46.9
5 2007 46.5
6 2005, 1981 46.3
8 1954 46.2
9 2015 46.0
10 1953 45.8
37 2017 44.0
 
   Top Ten Coldest Years on Record
Rank Year Average Temperature °F
1 1993 38.8
2 1924 39.5
3 1984, 1944 39.7
5 1978 40.1
6 1985 40.3
7 1968, 1929 40.5
9 1975 40.8
10 1986, 1932 41.0
59 2017 44.0

 

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 Average Annual Temperature for Period of Record - Click on Graph to Enlarge

  


 

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Precipitation Banner

Element Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
 Total (inches) 1.12 0.96 2.45 4.70 1.34 0.49 0.37 1.09 1.71 0.53 0.44 0.66 15.86
 Mean Precipitation
(1981-2010 Normals)
0.28 0.34 0.56 0.98 1.45 1.21 0.78 0.50 0.83 0.85 0.41 0.24 8.42
 Departure from Normal 0.84 0.63 1.89 3.72 -0.11 -0.72 -0.41 0.59 0.88 -0.32 0.03 0.42 7.44
 Percent of Normal 400 291 438 480 92 28 47 218 206 62 107 275 188

 Rank - Driest            to           Wettest
 100 years (P.O.R. 1918-2017)

96  95 98 100 44   28 39 92 90 40 58  89
 
100
 
 Greatest 24-HR Total  0.70 0.58  1.50 1.37 0.63  0.21 0.20 0.42 0.40 0.23 0.20 0.25 1.50
 Dates of Occurrence  24  24  31  26  19  12  28 13 15,23  2 2 21 3/31
 Number of Days with:                          
    Precipitation >= 0.01 5 5 6 15  8 5  5 6 11 6 6 6 84
    Precipitation >= 0.10 3 2  5 10  4  2  2 4 6 2 1 3 44
    Precipitation >= 1.00 0 0  1 1  0 0  0 0 0 0 0 0 2
Daily Precipitation Records Set or Tied 2 0  2 2  0  0 0 1 0 0 0 1 8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Precipitation Ranks and Records:
 

One Day Precipitation Records:

January: 0.70" on the 24th, 0.23" on the 2nd.
March: 0.47" on the 24h, 1.50" on the 31st (also an all-time daily record for March)

April: 1.37" on the 1st, 0.73" on the 19th.
August: 0.23" on the 7th.
December: 0.25" on the 21st.

 


 

    Wettest Months of January on Record
Rank Year Precipitation (inches)
1 1995 1.44
2 2017 1.12
3 1996 0.96
4 2014 0.63
5 1993 0.60
6 1953 0.56
7 1962 0.53
8 1932 0.51
9 2016, 1949,
1940
0.49
 
    Wettest Months of February on Record
Rank Year Precipitation (inches)
1 2004 1.33
2 2015 1.28
3 2003 1.15
4 1986 0.97
5 2017 0.96
6 1955 0.90
7 1935 0.86
8 1920 0.80
9 2011 0.75
10 1987 0.68
 
    Wettest Months of March on Record
Rank Year Precipitation (inches)
1 1998 2.95
2 2016 2.70
3 2017 2.45
4 1941 1.52
5 1992 1.21
6 1977 1.20
7 2009 1.15
8 1968 1.05
9 1958, 1924 1.03
 
    Wettest Months of April on Record
Rank Year Precipitation (inches)
1 2017 4.70
2 2016 3.82
3 1999 3.69
4 1944 3.47
5 1971 3.32
6 1941 2.96
7 1957 2.94
8 2004 2.80
9 1934 2.71
10 1945 2.32
 
    Wettest January - April Period on Record
Rank Year Precipitation (inches)
1 2017 9.23
2 2016 7.20
3 1944 4.79
4 1941 4.59
5 2004 4.23
6 1998 4.17
7 1995 3.86
8 1999 3.70
9 1971, 1945 3.58
 
    Wettest Months of August on Record
Rank Year Precipitation (inches)
1 1933 3.06
2 1930 2.90
3 1976 1.56
4 1941 1.28
5 1968 1.24
7 2004 1.21
8 2014 1.11
9 1983 1.10
10 2017 1.09
 
    Wettest Months of December on Record
Rank Year Precipitation (inches)
1 1955 0.96
2 2016 0.93
3 1997 0.89
4 1968 0.85
5 1982 0.79
7 1924 0.75
8 1972 0.72
9 1979 0.70
10 1985 0.68
11 2017 0.66
 

 

 

   Top Ten Driest Years on Record
Rank Year Precpitation (inches)
1 1988 3.75
2 2012 3.98
3 1974 4.12
4 1954 4.85
5 2001, 2006 5.07
7 1966 5.66
8 1990 5.71
9 1922 5.91
10 1932 6.05
100 2017 15.86
 
   Top Ten Wettest Years on Record
Rank Year Precipitation (inches)
1 1923 18.43
2 2017 15.86
3 2016 15.24
4 1941 14.74
5 1912 14.73
6 1993 13.49
7 1998, 1995 13.41
9 1971 13.11
10 1947 12.45
 

 

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 Annual Precipitation for Period of Record - Click on Graph to Enlarge
Click to enlarge
 Click on Graph to Enlarge

  


 

 

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  Snow Banner

Element Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
 Total (inches) 16.8 15.1 T 20.9 2.2 T 0.0 0.0 0.0 1.3 3.6 11.2 71.1
 Mean Snowfall (1981-2010 Normals) 4.8 6.0 5.9 6.1 1.2 0.0 0.0 0.0 0.3 3.7 4.3 4.8 37.1
 Departure from Normal 12.0 9.1 -5.9 14.8 1.0 0.0 0.0 0.0 -0.3 -2.4 -0.7 6.4 34.0
 Percent of Normal 350 252 0 343 183 0 0 0 0 35 84 233 192
  Rank - Least            to           Most
 92-100 years (P.O.R 1918-2017)
 92 90 7 90 78 NA NA NA 1* 56 48 81 91
 
 Greatest 24-HR Total 9.0 11.2 T 7.9  1.2 T  0.0 0.0 0.0 0.8 2.4 4.0 11.2
 Dates of Occurrence 24 24 6 4  19 12 NA NA NA  15 2 21 2/24
 Number of Days with:                          
    Snowfall >= 1.0 inch 4 2 0 5  2 0 0 0 0 0 1 4 18
Daily Snowfall Records Set or Tied 2 1 0 2  2 0 0 0 0 1 0 1 9


 * 82 months of September on record with no snowfall.16 was the 4th snowiest on record).
 

 

 

 

 

 

 

 

 

 

 

 





Snowfall Ranks and Records:
 

One Day Snowfall Records (inches):

  January:  5.3" on the 2nd, 9.0" on the 24th.
 
February: 11.2*" on the 24th (*all-time daily record for the month of February).
  April:  7.9" on the 4th, 6.2" on the 10th.

  May: 1.0" on the 18th, 1.2" on the 19th.
  October: 0.8" on the 15th.
  December: 4.0 on the 21st (tie).

 

   Snowiest Months of January on Record
Rank Year Snowfall (inches)
1 2017 16.8
2 1962 16.5
3 1995 15.9
4 1993, 1949 12.5
6 1980 12.0
6 1984 11.5
7 1972 10.4
8 2005 10.3
9 2014 10.1
10 1944 10.0
 
   Snowiest Months of February on Record
Rank Year Snowfall (inches)
1 1987 22.5
2 2015 17.8
3 2004 16.9
4 1959 16.0
5 2003 15.3
6 2017 15.1
7 1965 13.5
8 1935, 1920 13.0
10 2011 12.8
 
   Snowiest Months of April on Record
Rank Year Snowfall (inches)
1 1999 31.7
2 1920 29.0
3 2013 24.7
4 1945 22.1
5 1922 21.0
6 2017 20.9
7 1927 18.0
8 1979, 1924 17.0
10 1923 16.0
 

 

   Top Ten Snowiest Years on Record
Rank Year Snowfall (inches)
1 1920 77.0
2 2017 71.1
3 2013 70.6
4 2009 62.5
5 2016 61.7
6 2010 60.1
7 1919 58.0
8 1923 56.2
9 1944 55.4
10 1987 53.5

 

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Click to enlarge
 Annual and Seasonal Snowfall for Period of Record - Click on Graph to Enlarge

  

 


 

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