Frost dates · Montana
Montana frost dates,
county by county.
Last spring frost and first fall frost probability data for all 56 counties in Montana, computed from the NOAA 1991–2020 Climate Normals. Every county page surfaces the full probability table at three temperature thresholds plus crop-specific planting guidance.
Variation across Montana
885 days separate the earliest and latest counties.
The median last spring frost in Dawson County is April 24 — 885 days earlier than Sanders County at —. Statewide averages aren't useful planting tools; pick your county below for the data that actually applies to your fields.
Alphabetical
All Montana counties — A to Z.
- Beaverhead County
- Big Horn County
- Blaine County
- Broadwater County
- Carbon County
- Carter County
- Cascade County
- Chouteau County
- Custer County
- Daniels County
- Dawson County
- Deer Lodge County
- Fallon County
- Fergus County
- Flathead County
- Gallatin County
- Garfield County
- Glacier County
- Golden Valley County
- Granite County
- Hill County
- Jefferson County
- Judith Basin County
- Lake County
- Lewis and Clark County
- Liberty County
- Lincoln County
- Madison County
- McCone County
- Meagher County
- Mineral County
- Missoula County
- Musselshell County
- Park County
- Petroleum County
- Phillips County
- Pondera County
- Powder River County
- Powell County
- Prairie County
- Ravalli County
- Richland County
- Roosevelt County
- Rosebud County
- Sanders County
- Sheridan County
- Silver Bow County
- Stillwater County
- Sweet Grass County
- Teton County
- Toole County
- Treasure County
- Valley County
- Wheatland County
- Wibaux County
- Yellowstone County