Snyderville climate

Snyderville Frost Dates and Growing Season

NOAA 1991-2020 normals for Park City, 5.4 km from Snyderville, elevation 6900 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Park City. A median date has an even chance of a later freeze in spring, or an earlier one in fall.

The last spring freeze typically comes around May 29 and the first fall freeze around September 25, a growing season of about 117 days.

Median at 36°F
last June 10, first September 15
Median at 32°F
last May 29, first September 25
Median at 28°F
last May 12, first October 6

Last freeze in spring

The chance of a later freeze than the date shown. At 10 percent, one spring in ten still freezes after the date; planting after the 10 percent date for 32°F is the cautious choice.

Threshold10%20%30%40%50%60%70%80%90%
36°FJun 27Jun 22Jun 18Jun 14Jun 10Jun 7Jun 4May 31May 26
32°FJun 14Jun 8Jun 4Jun 1May 29May 26May 22May 17May 12
28°FJun 1May 25May 20May 16May 12May 9May 4Apr 30Apr 25
24°FMay 14May 7May 3Apr 30Apr 27Apr 22Apr 18Apr 14Apr 8
20°FApr 29Apr 20Apr 15Apr 11Apr 7Apr 5Apr 1Mar 27Mar 19
16°FApr 11Apr 5Apr 1Mar 27Mar 22Mar 17Mar 13Mar 8Mar 3

First freeze in fall

The chance of an earlier freeze than the date shown. At 10 percent, one fall in ten freezes before the date.

Threshold10%20%30%40%50%60%70%80%90%
36°FSep 3Sep 7Sep 10Sep 13Sep 15Sep 18Sep 21Sep 23Sep 27
32°FSep 12Sep 17Sep 20Sep 23Sep 25Sep 28Sep 30Oct 3Oct 9
28°FSep 23Sep 29Oct 1Oct 4Oct 6Oct 9Oct 13Oct 17Oct 21
24°FOct 4Oct 10Oct 14Oct 17Oct 20Oct 24Oct 26Oct 30Nov 3
20°FOct 17Oct 21Oct 25Oct 28Oct 31Nov 3Nov 6Nov 10Nov 14
16°FOct 25Oct 29Nov 2Nov 6Nov 9Nov 12Nov 15Nov 18Nov 23

Growing season length

Days between the last spring and first fall freeze at each threshold, with the chance of a season at least that long.

Threshold10%20%30%40%50%60%70%80%90%
36°F115107102979490868175
32°F14013312712211711310910497
28°F169162156151146142137131123
24°F200192186181177171166161153
20°F227218213208204199195188181
16°F255245239233229224217213203

How often it gets that cold

The share of years with at least one night at or below each temperature.

36°F or colder
100% of years
32°F or colder
100% of years
28°F or colder
100% of years
24°F or colder
100% of years
20°F or colder
100% of years
16°F or colder
100% of years

Degree days

A degree day is one degree of the daily mean temperature beyond a base, for one day. Heating degree days count cold (the fuel a house burns), cooling degree days heat, growing degree days the warmth a crop needs; each crop has its own base.

Heating degree days, base 65°F
7,934
Cooling degree days, base 65°F
170
Growing degree days, base 40°F
3,320
Growing degree days, base 45°F
2,384
Growing degree days, base 50°F
1,616
Growing degree days, base 55°F
989
Growing degree days, base 60°F
495

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,26600
February1,09500
March95501
April718011
May481192
June19819285
July3586516
August5559470
September2815205
October631034
November96802
December1,25200

What this means

NOAA computes these from the daily lows at the station over 1991-2020, fitting the dates of each year's last and first freeze to a distribution, so a date can be stated at any level of risk. 36°F is a frost risk for tender plants on a clear, calm night, since the ground cools below the air above it; 32°F is a freeze; 28°F is a hard freeze that kills most annuals.

The station is 5.4 km from Snyderville. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

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Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00426644 (Park City). Public domain.