Central City climate

Central City Frost Dates and Growing Season

NOAA 1991-2020 normals for Central City, 2.3 km from Central City, elevation 1700 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Central 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 April 28 and the first fall freeze around October 10, a growing season of about 165 days.

Median at 36°F
last May 6, first October 2
Median at 32°F
last April 28, first October 10
Median at 28°F
last April 17, first October 20

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 19May 14May 11May 8May 6May 3May 1Apr 28Apr 24
32°FMay 10May 5May 2Apr 30Apr 28Apr 25Apr 22Apr 18Apr 14
28°FMay 1Apr 26Apr 23Apr 20Apr 17Apr 15Apr 11Apr 8Apr 4
24°FApr 22Apr 18Apr 14Apr 11Apr 8Apr 5Apr 2Mar 30Mar 23
20°FApr 15Apr 9Apr 4Apr 1Mar 29Mar 26Mar 22Mar 16Mar 10
16°FApr 4Mar 30Mar 26Mar 22Mar 18Mar 15Mar 11Mar 7Mar 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 19Sep 25Sep 28Sep 30Oct 2Oct 5Oct 7Oct 10Oct 15
32°FSep 27Oct 1Oct 4Oct 7Oct 10Oct 13Oct 16Oct 19Oct 22
28°FOct 4Oct 10Oct 14Oct 17Oct 20Oct 22Oct 24Oct 28Nov 1
24°FOct 13Oct 19Oct 22Oct 25Oct 28Oct 31Nov 2Nov 6Nov 10
20°FOct 24Oct 28Nov 1Nov 3Nov 6Nov 8Nov 11Nov 16Nov 21
16°FOct 30Nov 4Nov 7Nov 11Nov 14Nov 17Nov 21Nov 25Nov 30

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°F164158155151147145141137131
32°F184178173169165161157153147
28°F202196191187184180176171163
24°F223215211207203198194189182
20°F244236231226222217212207199
16°F261254248243239235230224215

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
6,228
Cooling degree days, base 65°F
900
Growing degree days, base 40°F
5,407
Growing degree days, base 45°F
4,247
Growing degree days, base 50°F
3,216
Growing degree days, base 55°F
2,309
Growing degree days, base 60°F
1,535

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,26500
February1,02703
March793132
April4557119
May18654348
June24190617
July5298758
August10239694
September95101460
October40211164
November804021
December1,16400

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 2.3 km from Central 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 USC00251560 (Central City). Public domain.