Pollen today
Loading today’s values…
Pollen today
Loading today’s values…
Google gave no index for tree, grass or weed pollen here today.
Next four days, highest level each day:
Source: Includes pollen data from GoogleGoogle Maps
Source: Includes pollen data from GoogleIncludes data from Google Maps
Google’s index for each plant it models in San Francisco today. A plant out of season has no index.
Source: Includes pollen data from GoogleGoogle Maps
The forecast that moves pollen around, and the air beside it.
Forecast: National Weather Service, updated 10:26 am PT.
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Each thread is one kind of pollen, and each square is one week, colored by that week’s highest level.
Google has given no index for San Francisco since records began on October 15, 2026.
Highest level each week, November 2025 to November 2026, from each day’s forecast.
Source: Includes pollen data from GoogleIncludes data from Google Maps
What this forecast doesn’t measure, and when to get help.
Google’s index covers tree, grass and weed pollen only, so there is no mold level for San Francisco on this page. The National Allergy Bureau publishes pollen and mold counts measured at its stations. Our guides cover common molds such as Alternaria, Cladosporium and Aspergillus.
The forecast doesn’t cover allergens indoors either: dust mites, cockroaches, mice, cats and dogs. Our guides explain each one, starting with dust mites and cats.
An estimated 8.7% of adults in the city of San Francisco have current asthma, according to the CDC’s PLACES estimate for 2023 (95% confidence interval: 7.7% to 9.8%). It is a statistical estimate from national survey data, not a count.
89 allergists enrolled in Medicare practice in the San Francisco area: 1.92 for every 100,000 people, more than the 1.22 across the US. The count doesn’t show how soon you can get an appointment. See the doctors listed in the San Francisco area, or how every state and metro compares.
AllergyNest count from CMS’s Doctors and Clinicians file (October 2026) and Census population estimates for 2025.
The geography, climate and plants behind each season here, with a source for every fact.
Cool water from the Pacific Ocean and San Francisco Bay surrounds the city on three sides, at the northern end of a peninsula.2 Summers bring cool marine air and persistent low clouds and fog.2 Downtown, summers average about 61 °F and winters about 53 °F.1 More than 80 percent of the seasonal rain falls between November and March.2
The city’s planning department says San Francisco was naturally a non-forested environment, with fewer trees than the East Coast or other forested places.3 The first comprehensive census of its street trees, released in 2017, counted 124,795 of them from more than 500 species.4
Coast live oak grows along California’s Coast Ranges from Mendocino County southward.5 It is wind pollinated, and its catkins emerge in March and April.5 The National Park Service lists California sagebrush (Artemisia californica) as native and abundant in the Golden Gate National Recreation Area.6
Answered from the values on this page.
Very little. None of the plants Google models is above 0 in San Francisco today.
No. It’s Google’s modeled pollen index, from 0 (none) to 5 (very high), calculated for the location of central San Francisco. A pollen count is the number of pollen grains measured in a cubic meter of air at a counting station. How our pollen index works.
Twice a day. We fetch new values soon after midnight in San Francisco, so each day starts with its own values, and again after Google’s daily model run, usually by about 7:30 am PT. Each section shows when its values were retrieved.
Source: Includes pollen data from GoogleIncludes data from Google Maps