Medicine Lake, MT 59247 Frost Dates
When can you plant in Medicine Lake, MT?
Typically, the last spring freeze lands around 05/16, roughly 261 days out. The first fall frost typically arrives around 09/18, about 125 frost-free days later.
Zone 3b (-35 to -30°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Medicine Lake, not a forecast for this year.
What to do before the first frost
About 3 weeks of growing season left in Medicine Lake before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Medicine Lake's last frost
05/16 is the middle of 30 years of NOAA records, not a promise. Plant by 05/04 and you're betting against frost in roughly 9 years out of 10. 05/30 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Medicine Lake compares
About 125 days separate Medicine Lake's last and first frost, putting it 38,808 of 40,283 ZIP codes nationally. Within MT, it ranks 176 of 392.
Learn more
zone vs. frost date covers why Zone 3b and Medicine Lake's frost date answer different questions. the frost range covers how to read the range around Medicine Lake's dates instead of trusting one.