What is the hottest month in Merrill?

July is the warmest month in Merrill, with an average high of 80.2°F.

What is the coldest month in Merrill?

January is the coldest month in Merrill, with an average low of 3.4°F.

What month does Merrill get the most rain?

June is typically the wettest month in Merrill, with about 4.63 inches of precipitation.

What plant hardiness zone is Merrill in?

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

Has the climate in Merrill changed recently?

8.5% of Merrill'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.

Merrill, WI

Climate overview — based on NOAA 1991-2020 normals from MERRILL, WI US.

Dfb Warm-summer humid continental climate 5b USDA hardiness Zone 5b

Year-round temperatures (°F)

Avg high Avg low

Climate summary

Merrill has an annual average temperature of 42.1°F with about 33.8 inches of precipitation per year and 54.3 inches of snow. The warmest month is July (average high 80.2°F), and the coldest is January (average low 3.4°F). June is typically the wettest month (4.63 in) and February the driest (1.06 in). Snow typically falls from October through April.

Pleasant months

2 / 12

avg high 65–80°F, low ≥ 50°F

Annual swing

55.9°F

warmest to coldest month

Heating need

8,382

HDD/yr

Cooling need

147

CDD/yr

Best time to visit Merrill

Full guide →

Climate change signal

All-time records →

31 of 366 (8.5%) of Merrill'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		22
1910s		52
1920s		40
1930s		78
1940s		24
1950s		26
1960s		11
1970s		12
1980s		17
1990s		17
2000s		19
2010s		22
2020s		26

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	22.0°F	3.4°F	12.7°F	1.19 in	12.4 in	11
February	26.6°F	5.1°F	15.8°F	1.06 in	11.6 in	8
March	38.7°F	17.0°F	27.9°F	1.75 in	7.2 in	9
April	52.9°F	29.6°F	41.3°F	2.93 in	5.5 in	12
May	66.6°F	42.6°F	54.6°F	3.72 in	0.1 in	14
June	76.1°F	53.2°F	64.6°F	4.63 in	—	14
July	80.2°F	57.1°F	68.6°F	3.82 in	—	12
August	77.9°F	54.7°F	66.3°F	4.05 in	—	12
September	69.7°F	46.3°F	58.0°F	3.86 in	—	13
October	55.4°F	34.5°F	44.9°F	3.16 in	0.9 in	13
November	39.7°F	23.1°F	31.4°F	2.06 in	5.0 in	10
December	27.4°F	11.4°F	19.4°F	1.53 in	11.6 in	11