California
Health Risks
Infectious Diseases Risk
Moderate
→ Stable
Infectious Diseases is Low in Los Angeles, Sacramento, San Diego, San Jose, Palo Alto, and San Mateo, and High in San Francisco.
Allergy
Extreme
↓ Decreasing
Allergy is Moderate in Sacramento and San Diego, High in San Mateo, Very High in Los Angeles, and Extreme in San Francisco, San Jose, and Palo Alto.
Pollution
Low
↑ Increasing
Pollution is Low in Los Angeles, San Francisco, Sacramento, San Diego, San Jose, Palo Alto, and San Mateo.
Severe Weather
Low
→ Stable
Severe Weather is Low in Los Angeles, San Francisco, Sacramento, San Diego, San Jose, Palo Alto, and San Mateo.
Counties
Published by Hubbub World — health risk data for all US states and counties. Get the bub app for today's data and 30-day forecasts.
Frequently Asked Questions
What health risks does Hubbub World track for California?
Hubbub World tracks seven health risks for California: flu, COVID-19, RSV, infectious diseases overall, seasonal allergies, air pollution, and severe weather. Each risk is broken out by county and updated weekly. For today's risk levels and 30-day forecasts, get the bub app at https://bub.hubbubworld.com.
How often is California health risk data updated?
Health risk data for California is regenerated weekly. Each hub page shows the six most recent weekly snapshots — the most recently completed week and the five preceding weeks. Today's risk levels and 30-day forecasts are not on the web; they are exclusive to the bub app at https://bub.hubbubworld.com.
What methodology does Hubbub World use?
Hubbub World develops proprietary models on top of the underlying surveillance, environmental, and weather data to produce comparable risk scores across all U.S. counties. Each of the seven risks is reported on a four-point scale (Low, Moderate, High, Very High) so the scores are interpretable without needing the raw underlying numbers. The full methodology — including the modeling approach, validation against authoritative sources, and known limitations — is documented at https://www.hubbubworld.com/intelligence#methodology. The health risk data on Hubbub World is for informational purposes only and does not constitute medical advice. Always consult a healthcare professional for personal health decisions.
Where can I get today's health risk data for California?
Today's health risk levels and 30-day forecasts for California are exclusive to the bub app, available free on iOS, Android, and Apple Watch at https://bub.hubbubworld.com. The web hub is the historical archive — for live data and forward-looking forecasts, the bub app is the source of truth.
Does Hubbub World cover counties in California?
Yes. Hubbub World tracks every county (and county-equivalent) in California, with weekly historical risk data for each. County pages are linked from this state page. For today's data and 30-day forecasts at the county level, get the bub app at https://bub.hubbubworld.com.