What is the hottest month in Newcastle?

July is the warmest month in Newcastle, with an average high of 86.6°F.

What is the coldest month in Newcastle?

January is the coldest month in Newcastle, with an average low of 14.2°F.

What month does Newcastle get the most rain?

May is typically the wettest month in Newcastle, with about 2.90 inches of precipitation.

What plant hardiness zone is Newcastle in?

Newcastle is approximately in USDA plant hardiness Zone 6b, based on the average annual extreme minimum temperature.

Has the climate in Newcastle changed recently?

13.1% of Newcastle'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.

Newcastle, WY

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

BSk Semi-arid (cold) climate 6b USDA hardiness Zone 6b

Year-round temperatures (°F)

Avg high Avg low

Climate summary

Newcastle has an annual average temperature of 47.3°F with about 17.2 inches of precipitation per year and 38.9 inches of snow. The warmest month is July (average high 86.6°F), and the coldest is January (average low 14.2°F). May is typically the wettest month (2.90 in) and January the driest (0.51 in). Snow typically falls from September through May.

Pleasant months

1 / 12

avg high 65–80°F, low ≥ 50°F

Annual swing

49°F

warmest to coldest month

Heating need

6,846

HDD/yr

Cooling need

474

CDD/yr

Best time to visit Newcastle

Full guide →

Climate change signal

All-time records →

48 of 366 (13.1%) of Newcastle'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		10
1910s		28
1920s		27
1930s		73
1940s		15
1950s		11
1960s		12
1970s		9
1980s		17
1990s		52
2000s		58
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	34.6°F	14.2°F	24.4°F	0.51 in	6.8 in	6
February	37.6°F	16.2°F	26.9°F	0.67 in	7.7 in	6
March	48.3°F	25.5°F	36.9°F	0.77 in	4.9 in	6
April	57.0°F	33.3°F	45.2°F	1.70 in	5.0 in	8
May	66.3°F	43.3°F	54.8°F	2.90 in	0.6 in	11
June	77.6°F	53.0°F	65.3°F	2.68 in	—	11
July	86.6°F	60.2°F	73.4°F	2.54 in	—	9
August	85.6°F	58.5°F	72.1°F	1.82 in	—	7
September	75.1°F	49.0°F	62.0°F	1.20 in	0.2 in	6
October	58.9°F	35.5°F	47.2°F	1.24 in	1.4 in	7
November	45.0°F	24.2°F	34.6°F	0.59 in	5.5 in	5
December	34.6°F	15.0°F	24.8°F	0.54 in	6.8 in	6