County Data
Napa County, California
Self-reliance and preparedness data for Napa County
Relatively High
Hazard Risk (32.4/100)
9b
USDA Zone
257
Frost-Free Days
Good
Solar (5.1 kWh/m²/day)
Natural Hazard Risks in Napa County
| Hazard | Risk Rating | Score |
|---|---|---|
| Drought | Very High | 64.3 |
| Wildfire | Relatively Moderate | 24.6 |
| Riverine Flooding | Relatively High | 20.8 |
| Earthquake | Relatively Moderate | 20.5 |
| Landslide | Relatively Moderate | 15.0 |
Source: FEMA National Risk Index. Scores 0–100, higher = more risk.
Climate Profile
Temperature & Growing Season
| January Avg | 45°F |
| July Avg | 70°F |
| USDA Zone | 9b |
| Frost-Free Days | 257 |
Water & Energy
| Annual Precipitation | 27.5″ |
| Solar Potential | 5.1 kWh/m²/day |
| Wind Speed | 1.7 m/s |
| Soil Type | Loam |
Local Species
54
Edible species
23
Medicinal species
73
Autonomy Score
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Frequently Asked Questions
- What are the biggest natural hazards in Napa County, California?
- Napa County has an overall hazard rating of Relatively High based on FEMA National Risk Index data. The top threats are Drought, Wildfire, Riverine Flooding. Each hazard is scored 0–100 by likelihood and expected impact.
- What is the growing season in Napa County?
- Napa County is in USDA Hardiness Zone 9b with approximately 257 frost-free days per year. This determines which crops, fruit trees, and perennials can survive your winters and how long your outdoor growing season lasts.
- Is Napa County good for solar power?
- Napa County has a good solar rating. Solar potential is based on average daily irradiance (kWh/m²/day), which determines how much energy rooftop or ground-mounted panels can produce year-round.
- How many edible plants grow in Napa County?
- Our database identifies 54 edible plant species in Napa County based on regional flora data, USDA hardiness zone, and iNaturalist observations. The full field guide includes identification notes, preparation methods, and seasonal availability.
- What is the autonomy score for Napa County?
- Napa County has an autonomy score of 73. This composite score measures local self-reliance potential across water access, food production capacity, energy resources, and supply chain resilience. Higher scores indicate greater potential for self-sufficiency.