Silver City climate

Silver City Frost Dates and Growing Season

NOAA 1991-2020 normals for Ft Bayard, 12.3 km from Silver City, elevation 6099 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Ft Bayard. 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 April 4 and the first fall freeze around November 8, a growing season of about 216 days.

Median at 36°F
last April 20, first October 28
Median at 32°F
last April 4, first November 8
Median at 28°F
last March 12, first November 19

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°FMay 5May 1Apr 28Apr 24Apr 20Apr 16Apr 13Apr 9Apr 4
32°FApr 22Apr 15Apr 11Apr 7Apr 4Mar 31Mar 26Mar 20Mar 14
28°FApr 6Mar 30Mar 22Mar 17Mar 12Mar 9Mar 5Feb 28Feb 21
24°FMar 18Mar 9Mar 3Feb 26Feb 19Feb 13Feb 7Jan 31Jan 20
20°FFeb 27Feb 12Feb 3Jan 27Jan 18Jan 10Jan 3Dec 28Dec 16
16°FFeb 7Jan 28Jan 14Jan 7Jan 3Dec 31Dec 23Dec 14Dec 8

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°FOct 15Oct 19Oct 22Oct 25Oct 28Oct 30Nov 3Nov 6Nov 11
32°FOct 23Oct 29Nov 1Nov 5Nov 8Nov 11Nov 15Nov 18Nov 24
28°FNov 2Nov 8Nov 12Nov 16Nov 19Nov 22Nov 25Nov 30Dec 5
24°FNov 12Nov 19Nov 23Nov 27Nov 30Dec 3Dec 7Dec 11Dec 17
20°FNov 23Nov 30Dec 5Dec 9Dec 14Dec 18Dec 22Dec 28Jan 7
16°FDec 2Dec 8Dec 14Dec 19Dec 26Jan 1Jan 5Jan 13Feb 2

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°F210203197193189185180176170
32°F244234228221216212207201192
28°F276268260253247241236228218
24°F318306298291285278270262249
20°F360350343336332324316304288
16°F365365365365364357350339330

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
93% of years
16°F or colder
48% 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
3,178
Cooling degree days, base 65°F
1,225
Growing degree days, base 40°F
7,273
Growing degree days, base 45°F
5,655
Growing degree days, base 50°F
4,243
Growing degree days, base 55°F
3,050
Growing degree days, base 60°F
2,044

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January663012
February522025
March4101113
April2217246
May6974470
June2298745
July0343808
August0305770
September9179619
October15519335
November437091
December68809

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 12.3 km from Silver City. 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 USC00293265 (Ft Bayard). Public domain.