What is the hottest month in Riverton?

July is the warmest month in Riverton, with an average high of 87.9°F.

What is the coldest month in Riverton?

January is the coldest month in Riverton, with an average low of 4.2°F.

What month does Riverton get the most rain?

May is typically the wettest month in Riverton, with about 1.98 inches of precipitation.

What plant hardiness zone is Riverton in?

Riverton is approximately in USDA plant hardiness Zone 5b, based on the average annual extreme minimum temperature.

Has the climate in Riverton changed recently?

10.7% of Riverton's all-time daily heat records were set in the last decade (since 2015), compared to roughly 5% if records were evenly distributed over time.

Riverton, WY

Climate overview — based on NOAA 1991-2020 normals from RIVERTON, WY US.

BSk Semi-arid (cold) climate 5b USDA hardiness Zone 5b

Year-round temperatures (°F)

Avg high Avg low

Climate summary

Riverton has an annual average temperature of 43.9°F with about 9.5 inches of precipitation per year and 44.3 inches of snow. The warmest month is July (average high 87.9°F), and the coldest is January (average low 4.2°F). May is typically the wettest month (1.98 in) and December the driest (0.31 in). Snow typically falls from September through May.

Annual swing

54.9°F

warmest to coldest month

Heating need

7,890

HDD/yr

Cooling need

309

CDD/yr

Best time to visit Riverton

Full guide →

Climate change signal

All-time records →

39 of 366 (10.7%) of Riverton's all-time daily heat records have been set since 2015. If records were spread evenly across the station's history, only about 5% would fall in any given decade.

1900s		8
1910s		7
1920s		16
1930s		31
1940s		31
1950s		33
1960s		30
1970s		21
1980s		56
1990s		42
2000s		37
2010s		18
2020s		36

Bars: number of all-time daily heat records still standing that were set in each decade.

Monthly averages

Month	Avg High	Avg Low	Avg Temp	Precipitation	Snow	Rainy days
January	28.7°F	4.2°F	16.4°F	0.35 in	5.5 in	4
February	35.5°F	9.6°F	22.5°F	0.43 in	7.4 in	4
March	49.2°F	22.2°F	35.7°F	0.71 in	6.5 in	5
April	58.0°F	30.5°F	44.2°F	1.31 in	7.2 in	7
May	67.4°F	40.3°F	53.8°F	1.98 in	2.1 in	9
June	78.9°F	48.5°F	63.7°F	1.09 in	—	6
July	87.9°F	54.8°F	71.3°F	0.70 in	—	5
August	85.7°F	52.2°F	69.0°F	0.45 in	—	5
September	74.4°F	42.5°F	58.4°F	0.80 in	0.6 in	5
October	59.2°F	30.4°F	44.8°F	0.93 in	4.4 in	5
November	42.7°F	17.1°F	29.9°F	0.44 in	5.3 in	4
December	29.6°F	5.7°F	17.6°F	0.31 in	5.3 in	4