Modesto, CA Frost Dates: Last Spring and First Fall Frost

Frost leaves Modesto on January 31 and comes back on December 5 when the odds are even, a window of 312 days for tender plants.

Because half of all years do worse than the typical date, the dates that matter for tender plants are the late spring date, February 25, and the early fall date, November 20, each of which one year in ten fails to beat. Compared with the 100-city median of 229 days, Modesto gets 83 days extra before frost returns.

Behind every date on this page is one weather station, Modesto City CO AP (NOAA USW00023258), 3.0 miles east of Modesto's internal point in the Census Bureau's files and about 70 feet up.

Modesto's last spring frost, by chance

Frost is still possible on December 31 in nine springs out of ten and on January 31 in five; only one spring in ten sees a freeze as late as February 25.

There are 56 days between the early and late dates, a broader band than most cities on these pages show. In Modesto the typical date is a weaker promise than it looks.

When is the first frost in Modesto?

Expect the first freeze of fall by December 5 in a typical year. One year in ten brings it by November 20, and nine in ten have had it by January 6.

From the 10% date to the 90% date is 47 days, a wide band here, and the early date arrives 15 days before the typical one.

How long is the frost-free season in Modesto?

Modesto has far more frost-free days than the middle of these pages, and slow crops benefit most, as the planting dates below show. The gap between a typical year and a short one is 33 days, wider than for most cities on these pages. Count on 279 days, not 312 days, when a crop has little slack.

These figures are NOAA's own counts of freeze-free days across its simulated years, which is why they can differ a little from the days between the two typical dates. Nearly every winter reaches freezing at Modesto City CO AP: 97.1% of years record a night at or below 32°F, and the other 2.9% do not.

28°F dates in Modesto

Hard freezes are late to arrive in Modesto and early to leave: December 21 in fall, 16 days behind the first frost, and January 8 in spring, 23 days ahead of the last. At the edges, a 28°F night on or after February 6 happens one spring in ten and one by December 1 one fall in ten; the nine-in-ten dates are December 16 and January 20.

Using Modesto's frost dates in the garden

The University of New Hampshire Extension sheet times each crop from the last frost. For Modesto's typical date, January 31, that means cabbage on January 3, lettuce from January 3 to January 10, seed potatoes from January 17 to January 24, and, once the frost is behind you, peppers on February 14 and beans on or after January 31. The University of New Hampshire Extension sheet gives peas no frost count at all; sow them as soon as the soil thaws.

25 days lie between the typical and late dates in Modesto, enough to decide whether you plant tender crops early with a cover ready or wait for a safer spring.

Modesto's first frost leaves room for only 33 of the 34 fall crops, counting back NC State Extension's days to harvest and University of Georgia Extension's harvest allowance of 18 days; for the other 1 the last planting day falls before July. The slowest crop that still fits is bulb onions, which needs 138 days before the early first frost and so must be in by July 5.

Worked example: fall broccoli in Modesto

Take fall broccoli in Modesto. NC State Extension lists up to 80 days from transplant to harvest, and University of Georgia Extension adds a harvest allowance of 18 days, so the plants need 98 days before the first frost. Counting back from the typical first frost, December 5, the last planting day is August 29. Counting back from the early date, November 20, it is August 14.

15 days separate the two last days, enough that in Modesto the earlier one is worth following.

The same crop family has a spring clock too. University of New Hampshire Extension sets cabbage out ahead of the last frost, and from January 31 in Modesto that means on January 3.

Where Modesto's numbers are measured

The nearest usable station stands 3.0 miles east of Modesto's internal point, near the city but not in it.

Its elevation is about 70 feet. Of the 100 stations behind these pages, 81 sit higher and 18 lower. NOAA flags this station's record as representative, the code R, for the data behind its 50% last-frost value.

No elevation is available for Modesto in the Census data we saved, so the station's height may or may not match your garden's. Compare nearby stations in the frost dates tool if it does not, and err toward the colder dates.

How Modesto's frost dates compare

Modesto sits in a cluster: Stockton, CA is only 29 miles away, and the other two cities below are not much farther, so gaps in their dates come from local setting.

• Stockton, CA lies 29 miles north-west of Modesto. Typical last frost February 5, first frost December 8, 305 days between; spring frost lingers 5 days longer than in Modesto, and the season is within about a week of Modesto's.
• San Jose, CA (50 miles, south-west): the last frost is 29 days earlier than in Modesto, and the frost-free season is 50 days longer than Modesto's. Its typical dates are January 2 and December 25, with 362 days frost-free.
• Sacramento, CA lies 69 miles north of Modesto. Typical last frost January 12, first frost December 16, 341 days between; spring frost ends 19 days sooner than in Modesto, and the frost-free season is 29 days longer than Modesto's.

Put the frost dates to work

The frost dates tool opens on this station and lists every probability date, not just the ones above. From there, the spring planting planner and fall planting planner turn the dates into crop lists for Modesto, and the hardiness zone lookup answers what will overwinter.

All the cities on these pages are listed by state on the city frost dates index.

For California, the state planting pages copy the Extension calendar (UC Master Gardener Program) crop by crop and region by region: tomatoes in California, peppers in California, cucumbers in California, summer squash in California, green beans in California. Set those windows beside the frost dates above.

Where these numbers come from

Every frost and freeze date comes from the station's entry in NOAA's U.S. Climate Normals for 1991–2020 (doi:10.25921/4ek7-fk11), with no adjustment, and NOAA's documentation explains what each probability means. The Census Bureau's 2024 Gazetteer places Modesto on the map, and its Vintage 2024 estimates, 220,592 people here, decide which cities get a page.

University of New Hampshire Extension, NC State Extension and University of Georgia Extension supply the planting rules; this page only counts them from the station's dates. The methodology page explains how each figure is checked.

These dates describe odds over many years, not next week's weather. Look at the forecast before you plant, and keep a sheet or row cover ready for a night that does not follow the odds.