Frost dates 2026–2027

Frost dates for Glendora, California

Median (50% chance) dates of the last and first 32°F frost, from NOAA 1991–2020 climate normals at Pomona/fairplex, 6.4 mi away (close match).

Last spring frostJan 8
First fall frostDec 28
354 frost-free days
Last spring frostJan 81 year in 10 after Feb 18
First fall frostDec 281 year in 10 by Dec 5
Growing season354 daysbetween median 32°F dates
Hardiness zoneZone 10a30 to 35°F average extreme low

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Will it freeze in Glendora in the next 7 nights?

No overnight lows at or below 32°F are forecast in Glendora during the next 7 nights in the available NWS frost forecast.

Tonight: forecast low 57°F. Above 36°F.

NWS forecast period: Thu, Nov 5, 6:00 PM PST to Fri, Nov 6, 6:00 AM PST.

No nights at or below 36°F in the National Weather Service forecast for the next 7 nights.

Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.

Frost and freeze probabilities

Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.

These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.

Average first hard freeze in Glendora

Most years have no 28°F hard freeze at Pomona/fairplex, according to NOAA’s 1991–2020 Climate Normals. Check the short-term forecast above during cold snaps.

TemperatureLast spring date
90% · 50% · 10% chance of a later freeze
First fall date
10% · 50% · 90% chance of an earlier freeze
Season
36°F frost possible Dec 29 · Feb 8 · Mar 9 Nov 21 · Dec 10 · Dec 26 303 days
32°F freeze Dec 14 · Jan 8 · Feb 18 Dec 5 · Dec 28 · Feb 2 354 days
28°F hard freeze rare in most years rare in most years 365 days
NOAA NCEI U.S. Climate Normals 1991–2020, station USC00047050. How to read these probabilities.

Average high temperature by month

1991–2020 normals at Pomona/fairplex

Average low temperature by month

Months with lows near or below freezing carry frost risk

Where these frost dates come from

The frost dates for Glendora, CA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Pomona/fairplex (station USC00047050, elevation 999 ft), 6.4 mi from Glendora. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.

Frost dates near Glendora

CityDistanceLast spring frostFirst fall frost
San Dimas, CA 3.1 mi Jan 8 Dec 28
Azusa, CA 3.7 mi Jan 8 Dec 28
Covina, CA 4.3 mi Jan 8 Dec 28
La Verne, CA 5.0 mi Jan 8 Dec 28
Duarte, CA 6.2 mi Apr 28 Nov 15
West Covina, CA 6.8 mi Jan 8 Dec 28
Walnut, CA 7.5 mi Jan 8 Dec 28
Pomona, CA 7.5 mi Jan 8 Dec 28
Claremont, CA 8.1 mi Jan 8 Dec 28
Monrovia, CA 8.1 mi Apr 28 Nov 15

Frequently asked questions

When is the last frost in Glendora?

On average, the last spring frost (32°F) in Glendora is around January 8. In about 1 year in 10 it comes after February 18, and in 9 years in 10 it comes after December 14.

When is the first frost in Glendora?

The first fall frost (32°F) usually arrives around December 28. There’s a 10% chance of a freeze by December 5 and a 90% chance by February 2.

Can it frost in Glendora after the last frost date?

Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after February 8.

What growing zone is Glendora?

Glendora is in USDA Plant Hardiness Zone 10a (average annual extreme minimum temperature 30 to 35°F), based on the 2023 USDA map for ZIP code 91741. See growing zones in California.

More: all California frost dates · California growing zones · UV index today in Glendora · frost vs. freeze