Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 92630 — Lake Forest, CA

ZIP code 92630 (Lake Forest, Orange County) is in USDA zone 10b: the coldest winter night averages 35 to 40 °F.

Where ZIP 92630 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone10b35 to 40 °F
Coldest night1.7 to 4.4 °C
Last frostrare
First frostrare
2012 zone10a

Was 10a on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 10b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Lake Forest, CA…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates

A 32 °F frost doesn't happen here in most winters. At the nearest station (NOAA station Tustin Irvine Rch, CA — 6 miles away, elevation 236 ft) the median growing season is 365 days. When frost does come, it is a midwinter night or two; cover tender plants when a freeze is forecast.

Frost data: NOAA NCEI U.S. Climate Normals 1991–2020.

When spring arrived in 2026

In 2026, spring leaf-out near 92630 came on Jan 17 — 3 days earlier than the 1991–2020 average (Jan 20).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Soil in Lake Forest, CA

The soil mapped at the center of ZIP 92630 is Myford — sandy loam, moderately well drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding
pH5.6moderately acidic; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter0.75%low — add compost
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Myford sandy loam, 9 to 30 percent slopes, eroded.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 92630; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Lake Forest, CA

Summer high87 °Faverage high, August
Winter low43 °Faverage low, January
Hot days35days a year at 90 °F or more
Freezing nights2nights a year at 32 °F or less
Growing degree days5,449base 50 °F — the season’s usable heat
Longest day14 h 23 mindaylight on June 21
Shortest day9 h 55 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation15.3 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°100°32 °FJanuary: average high 68 °F, low 43 °F 68°43° JanFebruary: average high 69 °F, low 45 °F 69°45° FebMarch: average high 72 °F, low 48 °F 72°48° MarApril: average high 74 °F, low 50 °F 74°50° AprMay: average high 77 °F, low 55 °F 77°55° MayJune: average high 80 °F, low 58 °F 80°58° JunJuly: average high 85 °F, low 61 °F 85°61° JulAugust: average high 87 °F, low 63 °F 87°63° AugSeptember: average high 87 °F, low 61 °F 87°61° SepOctober: average high 84 °F, low 55 °F 84°55° OctNovember: average high 76 °F, low 47 °F 76°47° NovDecember: average high 70 °F, low 43 °F 70°43° Dec

Precipitation by month inches

0″1″2″3″4″January: 3.47 in precipitation 3.5 JanFebruary: 3.69 in precipitation 3.7 FebMarch: 1.98 in precipitation 2.0 MarApril: 0.88 in precipitation 0.9 AprMay: 0.45 in precipitation 0.5 MayJune: 0.09 in precipitation 0.1 JunJuly: 0.07 in precipitation 0.1 JulAugust: 0.01 in precipitation 0.0 AugSeptember: 0.14 in precipitation 0.1 SepOctober: 1.11 in precipitation 1.1 OctNovember: 1.10 in precipitation 1.1 NovDecember: 2.26 in precipitation 2.3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Tustin Irvine Rch, CA (6 mi away); precipitation: Mission Viejo 1.3 Sse, CA (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 10b.

9260910b
El Toro, CA · 1 mi
9269110b
Mission Viejo, CA · 3 mi
9261010b
Foothill Ranch, CA · 3 mi
9261810b
Irvine, CA · 3 mi
9269010b
Mission Viejo, CA · 3 mi
9265410b
Laguna Hills, CA · 3 mi
9269210b
Mission Viejo, CA · 3 mi
9263710b
Laguna Woods, CA · 3 mi

California planting zones →

Questions about 92630

What planting zone is ZIP code 92630?

ZIP code 92630 (Lake Forest, CA) is in USDA hardiness zone 10b on the 2023 map: the coldest night of an average winter reaches 35 to 40 °F (1.7 to 4.4 °C).

How much rain and snow does 92630 get?

About 15.3 inches of precipitation a year (NOAA 1991–2020 normals, Mission Viejo 1.3 Sse station).

How hot do summers get in Lake Forest, CA?

The average high peaks at 87 °F in August, with about 35 days a year at 90 °F or more.

What kind of soil does 92630 have?

The USDA soil survey maps Myford at the center of ZIP 92630: sandy loam, moderately well drained, pH about 5.6 (moderately acidic).

Did spring come early in Lake Forest, CA in 2026?

Spring leaf-out near 92630 came on Jan 17 in 2026, 3 days earlier than the 1991–2020 average (Jan 20), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Lake Forest, CA?

Intermediate onions: the longest day near 92630 is 14 h 23 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 92630 change?

Yes. The 2012 USDA map put 92630 in zone 10a; the 2023 map puts it in zone 10b. The newer map uses 1991–2020 data and more weather stations.