Zone 10a · Last frost ~Jan 2 · Soil 72.1°F today (measured) · See your place on the 2023 USDA zone map
This ZIP is part of Escondido, San Marcos & San Diego, where nearby ZIPs share the same stations and zone. That page compares every ZIP in the area.
Public NOAA/USDA data, updated 2026-10-16 19:24 UTC.
USDA Plant Hardiness Zone Map · San Marcos focus
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USDA Plant Hardiness Zone Map, 2023. Agricultural Research Service, U.S. Department of Agriculture. Accessed from https://planthardiness.ars.usda.gov/. Rendered unaltered from the PRISM Group, Oregon State University GIS data (https://prism.oregonstate.edu, accessed 15 Oct 2026) with official zone colors. Roads (TIGER/Line 2023 primary roads), place names (2023 Gazetteer) and state lines (2023 cartographic boundaries 1:500k) are drawn on top. Source: U.S. Census Bureau.
Zone
10a
USDA 2023 · 30 to 35°F
Last frost
Jan 2
avg last frost (50%)
Soil temp Measured
72.1°F
↓ 14.7° in 7 days
Chill hours
—
starts Nov 1
Rain
1.02″
since Oct 1 · normal 0.19″
Frost dates for 92096
Last spring frost
Jan 2
50% odds
First fall frost
Dec 30
50% odds
Safer spring date
Feb 4
10% chance of later frost
Growing season
365
days (50%)
Earliest-risk fall date (10%): Dec 8.
Station record: 19 of the 30 years in 1991–2020, which NOAA still uses for freeze dates. A full record would be more reliable.
NOAA NCEI U.S. Climate Normals 1991-2020, annual/seasonal freeze probabilities (32F) · CA ESCONDIDO #2 (USC00042863) 7.5 km away 19 yrs of record · about the same elevation
Newsletter · 92096
Frost alerts and planting reminders for 92096. Coming soon.
Ad strip · leaderboard 970×90 / 728×90
7-day forecast · High / Low / Rain / Frost / Wind
High wind: 1 day(s) with gusts ≥40 mph. Stake and protect transplants.
Fri 16
91°72°gust 46 mph💧2%
High wind
Sat 17
88°64°gust 33 mph💧3%
Clear
Sun 18
86°64°gust 15 mph💧1%
Clear
Mon 19
81°61°gust 15 mph💧11%
Clear
Tue 20
72°58°gust 26 mph💧64% · 0.04″
Rain
Wed 21
69°57°gust 22 mph💧64% · 0.60″
Rain
Thu 22
68°56°gust 17 mph💧33% · 0.11″
Clear
NOAA NWS api.weather.gov (SGX). Frost = low ≤32°F · High wind = gust ≥40 mph · 💧 = chance of precipitation and expected amount (NWS quantitative precipitation forecast; blank when NWS gives none) · Rain = chance ≥50%.
What to grow when · 92096
Calendar: San Diego County, coastal (guide Regions 1-2). Planting months from UC Master Gardeners of San Diego County; Master Gardener Association of San Diego County. Harvest months add typical days-to-harvest. This month also checks live soil temperature and the 7-day frost forecast. The harvest planner uses the same calendar. Rules: methodology.
ZIP 92096 (San Marcos, CA) is in USDA zone 10a (30 to 35°F average annual extreme minimum), per the 2023 USDA Plant Hardiness Zone Map.
When is the last frost in 92096?
Based on NOAA 1991–2020 normals at Ca Escondido #2 (7.5 km away), the median last 32°F freeze is Jan 2. In 1 of 10 years it is after Feb 4. The median first fall freeze is Dec 30.
Location: US Census Bureau 2023 Gazetteer, ZCTA internal point
Zone: USDA Plant Hardiness Zone Map 2023, ZIP datasets (USDA ARS + PRISM Climate Group, Oregon State University)
Frost: NOAA NCEI U.S. Climate Normals 1991-2020, annual/seasonal freeze probabilities (32F) CA ESCONDIDO #2 (USC00042863) 7.5 km away 19 yrs of record · about the same elevation
Forecast: NOAA National Weather Service api.weather.gov (7-day forecast + gridpoint wind gusts)
Soil: NOAA U.S. Climate Reference Network (USCRN) hourly02, SOIL_TEMP_10
Chill: CIMIS, California Department of Water Resources (hourly air temperature; QC-flagged hours dropped)
