First Frost Date by Zip Code Map
The first fall frost is the day your growing season ends for tender plants. Knowing roughly when it arrives lets you protect crops, bring in the harvest, and stop planting things that won’t have time to finish. This map gives you the average first frost date for your ZIP code.
How to use the map: enter your ZIP code in the search box below to see the average date of your first fall frost. Use it as a planning target — the point to have frost-tender plants harvested, covered, or moved indoors.
First Frost Date
Average first fall frost date
Monthly Rainfall
First frost dates on this map are calculated from a 30-year average of climate data from 1991 to 2020, which gives you a stable baseline rather than one unusual year, and they represent a typical, average date rather than a guarantee. Frost can arrive earlier or later in any given year. Low-lying frost pockets often freeze first, while sheltered, urban, or south-facing sites hold off longer.
Your first frost date pairs with your last spring frost date to define your frost-free growing season. For the full climate picture, also check your USDA hardiness zone.
What Is the First Frost Date?
The first frost date is the average date in autumn when temperatures first drop to about 32°F, cold enough to damage or kill frost-tender plants. It is a probability-based average from decades of records, not a fixed deadline, so treat it as the center of a window rather than an exact day.
When Is the First Frost in My Area?
It varies enormously by latitude, elevation, and proximity to water. Northern and high-elevation areas can see their first frost in early September, while the Deep South and coastal California may not frost until late November or December — if at all. The map above gives your local average so you don’t have to rely on a regional rule of thumb.
How to Use Your First Frost Date
- Protect tender plants. As the date nears, watch the forecast and be ready to cover or harvest on cold nights.
- Time your last plantings. Count back a crop’s days to maturity from your first frost to know whether a late sowing can finish in time.
- Plan the fall harvest. Bring in warm-season crops like tomatoes, peppers, and basil before the first frost; many cool-season crops shrug it off.
- Prep perennials. Use the approaching date as your cue to mulch, water in, and protect newly planted trees and shrubs for winter.
First Frost vs First Freeze
A light frost forms around 32°F and can damage tender foliage, while a hard freeze (about 28°F or below) kills most warm-season plants outright and reaches deeper into hardy ones. Standard frost dates are based on that first 32°F event, so your first hard freeze typically comes a bit later. Both are worth watching in fall.
How Accurate Is a First Frost Date Map?
It is a reliable average, but frost timing swings widely from year to year, and your exact site can frost earlier or later than the regional figure — a low spot where cold air pools may freeze weeks ahead of a nearby slope. Use the date for planning and always confirm with the local forecast on cold nights.
What is the first frost date?
It is the average autumn date when temperatures first fall to about 32°F, cold enough to harm frost-tender plants. It is a probability-based average from decades of weather records, not a guaranteed date.
When is the first frost in my area?
Use the map and ZIP lookup above for your local average. First frost ranges from early September in the far north and high elevations to late autumn — or not at all — in the Deep South and mild coastal areas.
Is the first frost date a guarantee?
No. It is a long-term average, so frost can arrive earlier or later in any given year. Treat it as the middle of a window and watch the forecast as the date approaches.
What’s the difference between a frost and a freeze?
A light frost happens around 32°F and damages tender foliage; a hard freeze (about 28°F or colder) kills most warm-season plants and affects hardier ones. First frost dates are based on the 32°F threshold.
How accurate is a first frost date map?
It is a solid 30-year average, but year-to-year timing varies widely and local terrain matters — a frost pocket can freeze well before a sheltered site nearby. Use it for planning and rely on the local forecast for any specific night.
Sources and Further Reading
- NOAA 1991–2020 U.S. Climate Normals, freeze/frost dates — the base data behind these first frost dates.
- NOAA probability-of-freeze data — methodology for average first-frost (32°F) dates.
Next step: use your frost dates to plan the whole season. Check your last spring frost date and frost-free days, or use the Plant Finder to match plants to your full climate.