Sparks climate

Sparks Frost Dates and Growing Season

NOAA 1991-2020 normals for Sparks, 2.9 km from Sparks, elevation 4357 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Sparks. 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 1 and the first fall freeze around October 10, a growing season of about 160 days.

Median at 36°F
last May 23, first October 1
Median at 32°F
last May 1, first October 10
Median at 28°F
last April 16, first October 23

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 9Jun 3May 31May 27May 23May 19May 14May 9May 4
32°FMay 25May 14May 8May 4May 1Apr 29Apr 26Apr 22Apr 17
28°FMay 2Apr 28Apr 23Apr 19Apr 16Apr 13Apr 9Apr 5Mar 30
24°FApr 18Apr 11Apr 6Apr 1Mar 27Mar 23Mar 17Mar 11Mar 3
20°FMar 27Mar 15Mar 8Mar 4Feb 28Feb 26Feb 21Feb 14Feb 5
16°FMar 1Feb 25Feb 20Feb 14Feb 8Feb 3Jan 29Jan 19Jan 6

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 16Sep 21Sep 25Sep 28Oct 1Oct 3Oct 5Oct 7Oct 11
32°FSep 29Oct 3Oct 5Oct 8Oct 10Oct 13Oct 16Oct 19Oct 24
28°FOct 7Oct 13Oct 17Oct 20Oct 23Oct 26Oct 30Nov 2Nov 6
24°FOct 20Oct 25Oct 29Nov 1Nov 4Nov 6Nov 10Nov 13Nov 18
20°FOct 29Nov 3Nov 8Nov 12Nov 15Nov 18Nov 21Nov 25Dec 1
16°FNov 8Nov 14Nov 19Nov 24Nov 29Dec 2Dec 6Dec 13Dec 26

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°F152145139134129124120114107
32°F178172167163160155151144135
28°F209201196191186182177173166
24°F247237230224218213208203196
20°F288278270263258252245238227
16°F330320309302295288280272260

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
4,878
Cooling degree days, base 65°F
706
Growing degree days, base 40°F
5,432
Growing degree days, base 45°F
4,091
Growing degree days, base 50°F
2,956
Growing degree days, base 55°F
2,031
Growing degree days, base 60°F
1,292

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January88501
February69605
March594029
April432194
May22322275
June61111501
July4275736
August6224684
September7570447
October3434164
November654020
December90702

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 2.9 km from Sparks. 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 USC00267697 (Sparks). Public domain.