Alexis climate

Alexis Frost Dates and Growing Season

NOAA 1991-2020 normals for Monmouth, 14.9 km from Alexis, elevation 720 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Monmouth. 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 22 and the first fall freeze around October 15, a growing season of about 174 days.

Median at 36°F
last May 4, first October 5
Median at 32°F
last April 22, first October 15
Median at 28°F
last April 11, first October 25

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 20May 14May 10May 6May 4May 1Apr 28Apr 25Apr 20
32°FMay 10May 3Apr 30Apr 26Apr 22Apr 19Apr 17Apr 13Apr 9
28°FApr 28Apr 22Apr 18Apr 15Apr 11Apr 9Apr 6Apr 3Mar 30
24°FApr 17Apr 11Apr 6Apr 4Apr 2Mar 31Mar 27Mar 22Mar 15
20°FApr 6Apr 1Mar 29Mar 25Mar 21Mar 18Mar 14Mar 11Mar 6
16°FMar 29Mar 23Mar 18Mar 15Mar 12Mar 9Mar 6Mar 3Feb 26

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 20Sep 25Sep 29Oct 2Oct 5Oct 7Oct 10Oct 14Oct 18
32°FSep 29Oct 5Oct 9Oct 12Oct 15Oct 18Oct 20Oct 24Oct 27
28°FOct 11Oct 17Oct 20Oct 23Oct 25Oct 28Oct 30Nov 2Nov 7
24°FOct 23Oct 27Oct 30Nov 1Nov 3Nov 6Nov 9Nov 14Nov 20
20°FNov 1Nov 4Nov 8Nov 10Nov 14Nov 17Nov 21Nov 25Dec 1
16°FNov 8Nov 13Nov 17Nov 21Nov 24Nov 27Dec 1Dec 5Dec 11

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°F172165161157154150146141135
32°F192186182178174170166161153
28°F216209204199196192187182174
24°F238230225220216212208203196
20°F258251247242237233228224217
16°F279273267262257253248242234

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
6,099
Cooling degree days, base 65°F
891
Growing degree days, base 40°F
5,498
Growing degree days, base 45°F
4,329
Growing degree days, base 50°F
3,283
Growing degree days, base 55°F
2,356
Growing degree days, base 60°F
1,555

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,30000
February1,05103
March795136
April4218137
May16164378
June20192622
July3277739
August8229687
September90103466
October37115183
November753031
December1,12702

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 14.9 km from Alexis. 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 USC00115768 (Monmouth). Public domain.