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🍂 First Frost Dates for Geraldine, Montana 59446

The first 36°F frost date is 30% likely to be on Sep 9. (See detailed probabilities below.)

The first 32°F light freeze date is 30% likely to be on Sep 19. (See detailed probabilities below.)

(See also 🌷 Last Spring Frost Dates.)

First frost date probabilities for Geraldine, MT are based on historical climate data.

Always check your local forecast for the most up-to-date frost warnings.

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What is a First Frost Date?

The first fall frost signals the end of your local growing season. This date serves as an important deadline for gardeners and farmers. You'll need to complete harvesting before this point. Annuals and other tender plants will die back when frost hits, and perennial plants will enter their dormant phase for winter. Meanwhile, it's time to enjoy a cup of hot cocoa and a cozy sweater—and start planning your spring garden!

How to use the First Frost Date?

Watch your local weather forecasts in early fall to predict the first frost date. Harvest tender crops and protect vulnerable plants before frost arrives. For late-summer plantings, count backward from your area's average first frost date. This ensures your crops have enough time to mature. Keep track of when frost actually occurs in your garden each year. This helps you identify protected spots where the growing season might last longer.

First Frost Date Probabilities

Probability of frost (36°F) on or before...
10% chanceAug 31
20% chanceSep 5
30% chanceSep 9
40% chanceSep 11
50% chanceSep 14
60% chanceSep 17
70% chanceSep 20
80% chanceSep 22
90% chanceSep 26
Probability of light freeze (32°F) on or before...
10% chanceSep 10
20% chanceSep 15
30% chanceSep 19
40% chanceSep 22
50% chanceSep 24
60% chanceSep 26
70% chanceSep 29
80% chanceOct 1
90% chanceOct 5
Probability of moderate freeze (28°F) on or before...
10% chanceSep 19
20% chanceSep 24
30% chanceSep 27
40% chanceSep 30
50% chanceOct 2
60% chanceOct 4
70% chanceOct 7
80% chanceOct 11
90% chanceOct 15
Probability of moderate hard freeze (24°F) on or before...
10% chanceSep 26
20% chanceOct 1
30% chanceOct 5
40% chanceOct 8
50% chanceOct 11
60% chanceOct 14
70% chanceOct 17
80% chanceOct 20
90% chanceOct 24
Probability of hard freeze (20°F) on or before...
10% chanceOct 4
20% chanceOct 10
30% chanceOct 14
40% chanceOct 17
50% chanceOct 20
60% chanceOct 24
70% chanceOct 27
80% chanceOct 30
90% chanceNov 4
Probability of severe hard freeze (16°F) on or before...
10% chanceOct 13
20% chanceOct 18
30% chanceOct 22
40% chanceOct 26
50% chanceOct 29
60% chanceNov 1
70% chanceNov 4
80% chanceNov 8
90% chanceNov 15

Agricultural climatic data from weather station: GERALDINE (USC00243445)

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