Smith Valley climate

Smith Valley Frost Dates and Growing Season

NOAA 1991-2020 normals for Smith 6 N, 10.9 km from Smith Valley, elevation 5000 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Smith 6 N. 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 23 and the first fall freeze around September 28, a growing season of about 127 days.

Median at 36°F
last June 7, first September 16
Median at 32°F
last May 23, first September 28
Median at 28°F
last May 5, first October 7

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 21Jun 16Jun 13Jun 9Jun 7Jun 4Jun 1May 28May 21
32°FJun 10Jun 5May 31May 28May 23May 18May 14May 9May 3
28°FMay 28May 20May 14May 9May 5May 2Apr 29Apr 25Apr 20
24°FMay 8May 2Apr 29Apr 26Apr 23Apr 20Apr 17Apr 13Apr 7
20°FApr 27Apr 19Apr 16Apr 12Apr 8Apr 5Mar 31Mar 25Mar 15
16°FApr 9Apr 3Mar 28Mar 21Mar 14Mar 8Mar 4Feb 27Feb 17

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 14Sep 16Sep 19Sep 23Sep 27Oct 2
32°FSep 12Sep 17Sep 22Sep 25Sep 28Oct 1Oct 3Oct 6Oct 11
28°FSep 24Sep 28Oct 1Oct 4Oct 7Oct 10Oct 14Oct 17Oct 22
24°FOct 3Oct 8Oct 12Oct 15Oct 18Oct 21Oct 24Oct 28Nov 1
20°FOct 13Oct 18Oct 21Oct 24Oct 27Oct 31Nov 2Nov 6Nov 11
16°FOct 22Oct 28Nov 1Nov 3Nov 6Nov 10Nov 13Nov 17Nov 22

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°F12411611010610197938881
32°F150143138132127122117111104
28°F174167163157154149144136128
24°F199190185180176172167161154
20°F227218211206200196190185178
16°F266254247242236229224217206

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
5,676
Cooling degree days, base 65°F
630
Growing degree days, base 40°F
4,934
Growing degree days, base 45°F
3,718
Growing degree days, base 50°F
2,698
Growing degree days, base 55°F
1,859
Growing degree days, base 60°F
1,174

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,01201
February79102
March670016
April497067
May26714239
June7894469
July4263724
August10208663
September11050395
October4332112
November770010
December1,03702

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 10.9 km from Smith Valley. 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 USC00267612 (Smith 6 N). Public domain.