Last frost date in Lafayette, CO
The average last frost in Lafayette is May 2. By May 14 the chance of another 32°F night drops to 1 in 10. The first fall frost usually arrives about October 11, which leaves 160 frost-free days. An early freeze before September 26 happens one year in ten.
- Safe after (10% risk)
- May 14
- Average first frost
- Oct 11
- Frost-free season
- 160 days
- Hard freeze (28°F) ends
- Apr 20
Frost possible in low spots Mon night, low 36°F
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2253°
- FriOct 2348°
- SatOct 2439°
- SunOct 2538°
- MonOct 2636°possible frost
- TueOct 2737°
- WedOct 2839°
Planting calendar for Lafayette
Windows count forward or back from the average frost dates above. Click a crop for dates across Colorado.
Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Apr 18 | May 2 | May 14 | Sep 26 | Oct 11 | Oct 24 |
| Hard freeze, 28°F | Apr 4 | Apr 20 | May 5 | Oct 7 | Oct 21 | Nov 4 |
Read the spring 10% column as the date after which only one year in ten still gets frost. That is the safer date for tomatoes, peppers and basil.
Where these numbers come from
NOAA station Northglenn (USC00055984) sits 8.1 miles from the center of Lafayette at 5,407 feet. Its averages cover 1991 to 2020. Low spots, valleys and open fields can keep getting frost a week or two after the station stops; city centers and lakeshores usually get less of it.
Questions
When is the last frost in Lafayette, CO?
The average last frost date in Lafayette is May 2, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 14.
When is the first frost in Lafayette?
The first frost in fall usually comes around October 11. One year in ten it arrives before September 26.
How long is the growing season in Lafayette?
About 160 days between the average last and first frost.
When should I plant tomatoes in Lafayette?
Plant tomato seedlings outside from May 9 to May 23. Start seeds indoors six to eight weeks earlier.
Nearby in Colorado
- LouisvilleMay 6
- BroomfieldMay 2
- ErieMay 7
- WestminsterMay 2
- BoulderMay 6
- NorthglennMay 2
- ThorntonMay 2
- ArvadaMay 5
- LongmontMay 7
- FirestoneMay 7
- Wheat RidgeMay 5
- BrightonMay 3