US Climate Insights
National analysis of temperature, precipitation, and extreme weather patterns across all 3,144 US counties. Data from NOAA NCEI 1991-2020 Climate Normals.
National Avg Temp
54.5°F
National Avg Precip
39.4"
Avg Heat Days
41
Counties Analyzed
2,938
Key Findings
The United States spans an extraordinary climatic range. Florida is the warmest state with an average annual temperature of 71.0°F across its counties, while Alaska is the coldest at 35.7°F. The 59°F seasonal swing in North Dakotarepresents one of the most dramatic climate transitions in the country, compared to just NaN°F in Hawaii.
Nationally, counties average 39.4 inches of precipitation annually and experience 41 days above 90°F per year. But these averages obscure the reality: some desert counties see fewer than 5 inches of rain and over 150 heat days annually, while Pacific Northwest counties may receive 80+ inches of rain with virtually no extreme heat.
State Temperature Rankings
Average annual temperature by state, computed from all counties with data. Southern states dominate the top, while northern mountain states and Alaska anchor the bottom.
Hottest States
Coldest States
National Temperature Distribution
How the 2,938 analyzed counties are distributed across temperature ranges. The US has a bimodal pattern: a large cluster in the 55-65°F range (Midwest / Northeast / Pacific) and another in the 65-75°F range (South / Southwest).
Temperature vs. Precipitation
Each point is a US county. Warmer counties tend to have more variable precipitation — from arid deserts (hot, dry, bottom-right) to humid subtropical zones (hot, wet, top-right). Bubble size represents extreme heat days. Click a point to explore that county.
Seasonal Temperature Swing by State
The difference between average July and January temperatures. States with continental climates (far from oceans, high latitude) show the largest swings. Coastal and southern states are most stable.
Largest Swings
Most Stable (Smallest Swings)
Most Extreme Heat Days
The 10 counties with the most days above 90°F per year. These are predominantly desert and southern counties where summer temperatures regularly exceed triple digits.
Starr County
TX
191 days
75.5°F avg
Yuma County
AZ
180 days
74.1°F avg
Imperial County
CA
180 days
73.7°F avg
La Paz County
AZ
178 days
72.4°F avg
Webb County
TX
174 days
73.4°F avg
Zapata County
TX
172 days
74.4°F avg
Hidalgo County
TX
171 days
74.8°F avg
Maricopa County
AZ
167 days
71.8°F avg
Brooks County
TX
160 days
72.2°F avg
Jim Hogg County
TX
158 days
73.9°F avg