
Based on 2,213 research-grade iNaturalist observations in California, Cloudless Sulphur is most often recorded in September; in California it behaves like a year-round resident. It ranks #50 among butterflies recorded in the state in our data.
Phoebis sennae
Cloudless Sulphur in California by month
Bars show research-grade observations per month. They mix true seasonality with how often people are outdoors, so treat small numbers with caution.
Also seen in California in September

Monarch

Fiery Skipper

Gulf Fritillary

Gray Hairstreak
Woodland Skipper

Gray Buckeye

Small White
Umber Skipper
Places to look in California
Botanical GardenThe Huntington Library, Art Museum, and Botanical Gardens
State ParkHearst Castle
Botanical GardenSan Francisco Botanical Garden
Anza-Borrego Desert State Park
Angeles National Forest
National ForestSequoia National Forest
FAQ
When does Cloudless Sulphur appear in California?
Mainly April–January, with the most records in September.
How common is Cloudless Sulphur in California?
It ranks #50 by number of iNaturalist observations among butterflies in California (2,213 records in our sample).