When is the last frost in Rio Hondo, TX?

For ZIP code 78583, the average last spring frost (32°F) is January 8, based on NOAA 1991-2020 climate normals for the Harlingen Rio Grande Ap, TX weather station. There is a 1-in-10 chance of a frost after February 17.

When is the first frost in Rio Hondo, TX?

The average first fall frost (32°F) is December 29. There is a 1-in-10 chance of frost by December 2, so tender plants are at risk from that point on.

How long is the growing season in 78583?

In half of years, the frost-free season (between the last and first 32°F frost) is at least 357 days long.

Are these frost dates a forecast?

No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.

Frost dates for 78583Rio Hondo, TX

The average last spring frost in Rio Hondo is January 8 and the average first fall frost is December 29, giving a typical growing season of about 357 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost: Jan 8
Average first fall frost: Dec 29
Growing season: 357 days

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
Temperature	Last spring: 90% / 50% / 10% chance	First fall: 10% / 50% / 90% chance	Growing season (50%)	Years with at least one
Light frost (36°F)	Dec 28 · Jan 31 · Mar 3	Nov 18 · Dec 13 · Jan 15	318 days	96%
Frost / freeze (32°F)	Dec 12 · Jan 8 · Feb 17	Dec 2 · Dec 29 · Feb 1	357 days	61%
Hard freeze (28°F)	Dec 14 · Jan 2 · Feb 1	Dec 13 · Jan 1 · Jan 28	365 days	18%

Where these dates come from

ZIP code 78583 is matched to the NOAA station Harlingen Rio Grande Ap, TX, 10.3 km away, at 34 ft elevation (8 ft higher than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
Harlingen Rio Grande Ap, TX (used)	34 ft	Jan 8	Dec 29
Harlingen, TX	38 ft	Jan 9	Jan 3
Port Isabel Cameron Ap, TX	19 ft	Jan 8	Jan 4
Port Isabel, TX	17 ft	Jan 3	Jan 1

Frost dates near Rio Hondo

Lozano, TX 78568 · last Jan 8, first Dec 29
Harlingen, TX 78550 · last Jan 9, first Jan 3
San Benito, TX 78586 · last Jan 9, first Jan 3
Combes, TX 78535 · last Jan 9, first Jan 3
Los Fresnos, TX 78566 · last Jan 8, first Jan 4
Olmito, TX 78575 · last Jan 6, first Jan 2
Santa Rosa, TX 78593 · last Jan 10, first Dec 27
Los Indios, TX 78567 · last Jan 9, first Jan 3

Frequently asked questions

When is the last frost in Rio Hondo, TX?: For ZIP code 78583, the average last spring frost (32°F) is January 8, based on NOAA 1991-2020 climate normals for the Harlingen Rio Grande Ap, TX weather station. There is a 1-in-10 chance of a frost after February 17.
When is the first frost in Rio Hondo, TX?: The average first fall frost (32°F) is December 29. There is a 1-in-10 chance of frost by December 2, so tender plants are at risk from that point on.
How long is the growing season in 78583?: In half of years, the frost-free season (between the last and first 32°F frost) is at least 357 days long.
Are these frost dates a forecast?: No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.