Riverton 2011 Annual Climate Summary

2011 Climate Summary for Downtown Riverton

Month

Avg

High

Avg

Low

Average

Temp

Departure

From

Normal

Total

Pcpn

Departure

From

Normal

Snowfall

Avg Snow

Departure

January

27.2

5.6

16.4

-2.2

0.25

-0.03

  6.7

4.8

 1.9

February

27.5

2.6

15.1

-9.1

0.75

 0.42

12.8

6.0

 6.8

March

50.4

24.7

37.6

  1.5

0.08

-0.48

  1.0

5.9

-4.9

April

57.4

29.2

43.3

-2.1

0.28

-0.70

  1.7

6.1

-4.4

May

60.3

36.3

48.3

-6.3

5.29

  3.84

  5.6

1.2

  4.4

June

77.7

46.8

62.3

-1.5

0.68

-0.53

  0.0

T

  0.0

July

90.3

56.7

73.5

  2.4

0.08

-0.70

  0.0

0.0

  0.0

August

89.8

53.9

71.9

   2.9 

0.53

  0.03

  0.0

0.0

  0.0

September

78.0

44.1

61.1

   2.9 

0.43

 -0.40

  0.0

0.3

 -0.3

October

63.0

35.5

49.3

  4.3

1.66

  0.81

  2.2

3.7

 -1.5

November

43.6

17.7

30.7

   0.4 

0.45

  0.04

  5.8

4.3

  1.5

December

28.8

3.9

16.4

  -1.0 

0.20

 -0.04

  4.2

4.8

 -0.6

Total/Ave

57.8

29.8

43.8

 -0.7

10.68

  2.26

40.0

37.1

   2.9 

The table above is using the 1981-2010 normals for temperature and precipitation. 

Yearly Extremes:

Highest Temperature:   98 Degrees on July 3rd 

              Lowest Temperature:     -24 Degrees on February 9th

Days with Maximum Temperature 90 Degrees F or Higher:    33

Days with Maximum Temperature 32 Degrees F or Lower      63

Days with Minimum Temperature 32 Degrees F or Lower     189

Days with Minimum Temperature 0 Degrees F or Lower          31

 

Most Precipitation in 24 Hours:  2.21 inches on May 19th 
Most Precipitation in One Day:
2.21 inches on May 19th
Most Snowfall in 24 Hours: 
5.8 inches on Jan 9th  
Most Snowfall in One Day:  5.8 inches on Jan 9th
  


 

 

 Monthly Reviews:

 

JANUARY 2011 - Colder than Normal

Riverton's January average temperature was 16.4 degrees which was 2.2 degrees below normal.  The coldest low temperature was 21 degrees below zero on the 1st.  The warmest high temperature was 50 degrees on the 17th.

Precipitation for January was 0.25 inches which was 0.03 inches below normal.  Snowfall was 6.7 inches which was above normal.  Snow depth ranged from a high of 9 inches on the 10th to a low of 2 inches on the 31st.

FEBRUARY 2011 - Much Wetter than Normal and Much Colder than Normal

Riverton's February average temperature was 15.1 degrees which was 9.1 degrees below normal.  February 2011 was the 16th Coldest on record.  The coldest low temperature was 24 degrees below zero on the 9th.  The warmest high temperature was 56 degrees on the 13th.

Precipitation for February was 0.75 inches which was 0.42 inches above normal for the month.  February 2011 was the 8th Wettest on record.  Snowfall was 12.8 inches.  This made February 2011 the 7th Snowiest on record.  Snow depth ranged from a high of 8 inches on the 8th to a low of 1 inch on the 25th.

MARCH 2011 - Warmer than Normal and Much Drier than Normal

Riverton's March average temperature was 37.6 degrees which was 1.5 degrees above normal.  The coldest low temperature was 10 degrees on the 1st.  The warmest high temperature was 63 degrees on the 16th and the 21st.

Precipitation for March was 0.08 inches which was 0.48 inches below normal.  March 2011 tied for the 8th Driest on record with March 1921.  Snowfall was 1.0 inches which was well below normal. 

APRIL 2011 - Colder than Normal and Much Drier than Normal

Riverton's April average temperature was 43.3 degrees which was 2.1 degrees below normal.  The coldest low temperature was 14 degrees on the 4th.  The warmest high temperature was 73 degrees on the 2nd. 

Precipitation for April was 0.28 inches which was 0.70 inches below normal.  This tied for the 9th Driest on record.  Snowfall was 1.7 inches which was well below normal. 

MAY 2011 - Much Colder than Normal and Much Wetter than Normal

Riverton's May average temperature was 48.3 degrees which was 6.3 degrees below normal.  May 2011 tied for the 2nd Coldest on record with May 1935.  The coldest low temperature was 19 degrees on the 1st.  The warmest high temperature was 73 degrees on the 5th and the 8th.

Precipitation for May was 5.29 inches which was 3.84 inches above normal.  May 2011 was the 2nd Wettest May on record.  Snowfall was 5.6 inches.  May 2011 was the 6th Snowiest on record.  Two major precipitation events occurred...May 18th through the 20th when 2.78 inches occurred.  The other event was May 29th and 30th (Memorial Day weekend) when 1.93 inches occurred and 5.6 inches of snow was recorded.  

JUNE 2011 - Wetter than Normal

Riverton's June average temperature was 62.3 degrees which was 1.5 degrees below normal.  The coldest low temperature was 35 degrees on the 3rd and 4th.  The warmest high temperature was 94 degrees on the 28th.

Precipitation for June was 0.68 inches which was 0.53 inches below normal.  There was no snowfall in June. 

JULY 2011 - Much Warmer than Normal and Much Drier than Normal

Riverton's July average temperature was 73.5 degrees which was 2.4 degrees above normal.  July 2011 tied for the 8th Warmest on record  July 2008.  The coldest low temperature was 49 degrees on the 21st.  The warmest high temperature was 98 degrees on the 3rd.  The high temperature was greater than 80 degrees each day of the month.  The high temperature was 90 degrees or higher on 17 days. 

Precipitation for July was 0.08 inches which was 0.70 inches below normal.  July 2011 tied for 10th Driest on record with July 1924.  Measurable rain (0.01 inches or more) occurred on only 2 days. 

AUGUST 2011 - Much Warmer than Normal

Riverton's August average temperature was 71.9 degrees which was 2.9 degrees above normal.  August 2011 was the 4th Warmest on record.  The coldest low temperature was 48 degrees on the 19th and 20th.  The warmest high temperature was 97 degrees on the 27th.  The high temperature was greater than 80 degrees each day of the month.  The high temperature was 90 degrees or higher on 14 days.

Precipitation for August was 0.53 inches which was 0.03 inches above normal. 

SEPTEMBER 2011 - Much Warmer and Drier than Normal 

Riverton's September average temperature was 61.1 degrees which was 2.9 degrees above normal.  September 2011 was the 9th Warmest on record.  The coldest low temperature was 30 degrees on the 21st.  The warmest high temperature was 88 degrees on the 1st.  The high temperature was 80 degrees or higher on 15 days.

Precipitation for September was 0.43 inches which was 0.40 inches below normal.  No snowfall occurred this month.

OCTOBER 2011 - Much Warmer and Wetter than Normal

Riverton's October average temperature was 49.3 degrees which was 4.3 degrees above normal.  October 2011 was the 8th Warmest on record.  The coldest low temperature was 19 degrees on the 28th.  The warmest high temperature was 84 degrees on the 1st and 2nd.    

Precipitation for October was 1.66 inches which was 0.81 inches above normal.  Snowfall was 2.2 inches which was below normal.

NOVEMBER 2011 - Near Normal Conditions

Riverton's November average temperature was 30.7 degrees which was 0.4 degrees above normal.  The coldest low temperature was 3 degrees below zero on the 20th.  The warmest high temperature was 57 degrees on the 4th and the 17th. 

Precipitation for November was 0.45 inches which was 0.04 inches above normal.  Snowfall was 5.8 inches which was above normal. 

DECEMBER 2011 - Colder than Normal

Riverton's December average temperature was 16.4 degrees which was 1.0 degrees below normal.  The coldest low temperature was 15 degrees below zero on the 24th.  The warmest high temperature was 50 degrees on the 29th. The first 25 days saw temperatures stay below freezing.  A warmup occurred on the last 6 days of the month. 

Precipitation for December was 0.20 inches which was 0.04 inches below normal.  Snowfall was 4.2 inches which was slightly below normal. 

 In Summary...2011 was a wetter than normal year in Downtown Riverton.  Temperatures were colder than normal the first half of the year.  Then temperatures were warmer than normal the second half of the year.   Precipitation was generous the first half the year with 69% of the year's total occurring from January through June.  The last half of the year was fairly dry.



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