In California, the moth most likely on your sheet or porch light right now is the White-lined Sphinx (Hyles lineata) — a fast, hummingbird-like hawkmoth that is far and away the most-recorded moth in the state across nearly every month. Beyond it, the most-recorded species in open GBIF records lean heavily Californian: the Ceanothus Silkmoth (Hyalophora euryalus), the West's answer to the cecropia, flies spring into early summer; the day-flying Elegant Sheep Moth (Hemileuca eglanterina) peaks in mid-summer; and the California Oakworm moth (Phryganidia californica) builds toward a strong fall showing. You'll also commonly turn up tiger moths like the Painted Tiger Moth (Arachnis picta), Salt Marsh Moth (Estigmene acrea), the spotted Lophocampa maculata, and the woolly-bear adult Isabella Tiger Moth (Pyrrharctia isabella). Spring brings tent-caterpillar moths (Malacosoma californica and M. constricta) and fairy moths (Adela); winter, unusually, stays busy with geometrids like Hydriomena nubilofasciata and early Orthosia and Egira noctuids. This page reflects the most-recorded, most-likely species over an approximate California area from open-licensed records — a discovery list, not an exhaustive checklist.
When do the giant silk moths and hawkmoths fly in California?
California doesn't get the eastern showstoppers — there's no luna, cecropia, polyphemus, io, or imperial in this data. Instead, the state has its own large, charismatic moths, and the records show clearly when to look.
The standout hawkmoth is the White-lined Sphinx (Hyles lineata), which dominates the records nearly year-round but explodes in March and April — over 490 and 500 records in those months, by far the biggest single-species counts in the dataset. These are the dusk-flying "hummingbird moths" you'll see hovering at flowers; in big desert-bloom years they appear in remarkable numbers. Other true sphinx moths show a summer signature: the Elegant Sphinx (Sphinx perelegans) and Cerisy's / One-eyed Sphinx (Smerinthus cerisyi) turn up in June and July, the Carolina Sphinx (Manduca sexta, the tomato/tobacco hornworm adult) runs July through October, the Achemon Sphinx (Eumorpha achemon) appears in August, and the small bumblebee-mimic clearwing Hemaris thetis shows up in late summer.
For giant silk moths (Saturniidae), California's signatures are two: the Ceanothus Silkmoth (Hyalophora euryalus), a deep red-brown giant that peaks March through June, and the Elegant Sheep Moth (Hemileuca eglanterina), a pink-and-yellow day-flier most-recorded June through August. If you want the big moths, spring is for the silkmoth and mid-summer is for the sheep moth.
What's flying in spring (March-May)?
Spring is the busiest, most charismatic window. The White-lined Sphinx surges, and it's joined by a wave of tent-caterpillar moths — Malacosoma californica and especially Malacosoma constricta (over 110 records in April) — plus the tussock moth Orgyia vetusta and the white Spilosoma vestalis. Day-flying fairy moths with absurdly long antennae appear now too: Adela trigrapha, Adela septentrionella, and Adela flammeusella are all spring-specific here. Tiger moths join in with the Painted Tiger Moth (Arachnis picta) and Arctia tigrina, and the imported Large Yellow Underwing (Noctua pronuba) climbs to over 200 records by May. The Ceanothus Silkmoth is in flight throughout.
What about mid-summer (June-August)?
The lineup shifts noticeably. White-lined Sphinx counts drop from their spring peak but stay high (and rebound in August), while the Sheep Moth (Hemileuca eglanterina) and the day-flying Sierra Pericopid (Gnophaela latipennis) become characteristic. Tiger moths swap leads: the Salt Marsh Moth (Estigmene acrea) and the spotted Lophocampa maculata are reliable, and the silvery Lophocampa argentata tails off from spring. Summer also brings a run of Pyrausta crambid micromoths (volupialis, californicalis, semirubralis) and the filbertworm moth Cydia latiferreana. The sphinx moths listed above — Carolina, Elegant, Cerisy's, Achemon — are all a summer phenomenon here.
What's flying in fall (September-November)?
Fall has a distinct, very Californian character. The California Oakworm moth (Phryganidia californica) is near the top of the list September and October, and Edwards' Glassy-wing (Hemihyalea edwardsii) — a large pale tiger moth tied to oaks — leads all species in October (156 records). You'll also find the Isabella Tiger Moth (Pyrrharctia isabella, the adult of the familiar woolly bear), the Painted Tiger Moth returning, and Neoalcis californiaria. By November the Sooty-winged Chalcoela / Uresiphita reversalis (the Genista broom moth) tops the much shorter list as activity winds down.
Is there really mothing in a California winter?
Yes — and this is one of the things that makes California unusual. Many states go quiet, but here December and January still have 18 most-recorded species. Winter is geometrid season: Hydriomena nubilofasciata peaks hard in February (178 records) and the early-spring Orthosia and Egira noctuids (Egira hiemalis, Orthosia pacifica, Egira cognata) are already flying. Even the White-lined Sphinx shows up in small numbers in midwinter. If you're in coastal or low-elevation California, a mild winter night is genuinely worth a porch light.
How do I get tonight's California list?
The lists above are the state's most-recorded species by month, but the moths at your spot depend on your exact location, the date, and the night's conditions. Enter your location and Tonight's Moths builds a personalized list of the species most likely flying near you tonight from open GBIF records, alongside a "good mothing night" score that weighs weather and the moon — warm, still, overcast, near-new-moon nights tend to score highest. We're a forecast and discovery tool, not an identifier: once you've photographed something, confirm the ID on iNaturalist or BugGuide / the Moth Photographers Group.
Frequently asked
What is the most common moth in California?In open GBIF records, the most-recorded moth across California is the White-lined Sphinx (Hyles lineata), a hummingbird-like hawkmoth. It tops the list in nearly every month and peaks dramatically in March and April, when it can appear in large numbers, especially in years with strong desert and chaparral blooms.
Are there luna moths or cecropia moths in California?No — luna, cecropia, polyphemus, io, and imperial moths are eastern and midwestern species and don't appear in California's records. California's signature large moths are different: the Ceanothus Silkmoth (Hyalophora euryalus), a western relative of cecropia, and the day-flying Elegant Sheep Moth (Hemileuca eglanterina).
When is the best time of year to see moths in California?Spring (March-May) is the most active and charismatic window, led by the White-lined Sphinx surge, the Ceanothus Silkmoth, tent-caterpillar moths, and long-antennaed fairy moths. Fall is excellent too, with the California Oakworm moth and Edwards' Glassy-wing peaking. Unusually, winter stays productive on mild nights, with geometrids and early Orthosia noctuids flying.
Can this tool identify a moth from my photo?No. Tonight's Moths is a forecast and discovery tool — it tells you which species are most likely flying near you tonight based on open records, plus a good-mothing-night score. For confirming an ID from a photo, we point you to iNaturalist or the Moth Photographers Group / BugGuide.
Is the California species list complete?No. These are the most-recorded, most-likely species drawn from open-licensed GBIF records over an approximate California area, so it skews toward moths people photograph and report. It's a discovery list to know what to watch for, not an exhaustive checklist of every moth in the state — California has thousands of species.
Top moth species per month from open-licensed GBIF records (CC0/CC-BY), aggregated over an approximate state bounding box. Butterflies excluded. GBIF download DOI: 10.15468/dl.3w3w76. Independent project; not affiliated with iNaturalist or Butterfly Conservation.