Leola climate

Leola Frost Dates and Growing Season

NOAA 1991-2020 normals for Leola, 0.5 km from Leola, elevation 1580 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Leola. 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 9 and the first fall freeze around September 28, a growing season of about 141 days.

Median at 36°F
last May 18, first September 20
Median at 32°F
last May 9, first September 28
Median at 28°F
last May 1, 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°FMay 31May 26May 23May 20May 18May 16May 14May 11May 7
32°FMay 21May 16May 14May 11May 9May 6May 4May 2Apr 28
28°FMay 13May 8May 5May 3May 1Apr 29Apr 26Apr 23Apr 18
24°FMay 5May 1Apr 28Apr 25Apr 22Apr 19Apr 16Apr 13Apr 9
20°FApr 26Apr 22Apr 18Apr 16Apr 13Apr 10Apr 8Apr 5Apr 1
16°FApr 18Apr 14Apr 10Apr 7Apr 5Apr 3Mar 31Mar 26Mar 21

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 8Sep 12Sep 16Sep 18Sep 20Sep 22Sep 24Sep 27Oct 1
32°FSep 17Sep 21Sep 23Sep 26Sep 28Sep 30Oct 2Oct 5Oct 10
28°FSep 25Sep 28Oct 1Oct 3Oct 6Oct 9Oct 12Oct 15Oct 19
24°FOct 1Oct 6Oct 9Oct 12Oct 15Oct 18Oct 20Oct 23Oct 26
20°FOct 9Oct 15Oct 18Oct 21Oct 24Oct 26Oct 30Nov 1Nov 6
16°FOct 19Oct 24Oct 27Oct 31Nov 2Nov 5Nov 7Nov 12Nov 17

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°F139134130127124120117112106
32°F159153149145141138134130123
28°F176170166162158155151147142
24°F193188183179175171167162156
20°F213206201197194190186182175
16°F230223219214211207203198192

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
8,741
Cooling degree days, base 65°F
475
Growing degree days, base 40°F
4,072
Growing degree days, base 45°F
3,123
Growing degree days, base 50°F
2,278
Growing degree days, base 55°F
1,552
Growing degree days, base 60°F
941

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,66700
February1,38000
March1,15901
April685134
May31413209
June7394471
July18196643
August37135563
September20636297
October638157
November1,06903
December1,49400

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 0.5 km from Leola. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

More

Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00394891 (Leola). Public domain.