Scio climate

Scio Frost Dates and Growing Season

NOAA 1991-2020 normals for Lacomb 3 Nne, 13.6 km from Scio, elevation 520 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Lacomb 3 Nne. 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 26 and the first fall freeze around October 24, a growing season of about 184 days.

Median at 36°F
last May 14, first October 5
Median at 32°F
last April 26, first October 24
Median at 28°F
last March 24, first November 12

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 1May 26May 21May 17May 14May 11May 8May 4Apr 30
32°FMay 11May 5May 1Apr 29Apr 26Apr 22Apr 17Apr 11Apr 4
28°FApr 19Apr 7Apr 1Mar 29Mar 24Mar 17Mar 10Feb 28Feb 21
24°FMar 19Mar 3Feb 27Feb 21Feb 16Feb 9Jan 31Jan 16Dec 31
20°FFeb 26Feb 17Feb 4Jan 26Jan 14Jan 5Dec 29Dec 17Dec 5
16°FFeb 17Feb 1Jan 20Jan 6Dec 31Dec 27Dec 19Dec 11Dec 4

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 15Sep 23Sep 28Oct 1Oct 5Oct 8Oct 13Oct 18Oct 27
32°FOct 5Oct 12Oct 17Oct 20Oct 24Oct 28Nov 1Nov 7Nov 14
28°FOct 22Oct 29Nov 2Nov 8Nov 12Nov 18Nov 25Dec 3Dec 12
24°FNov 4Nov 13Nov 23Nov 30Dec 5Dec 11Dec 21Dec 28Jan 13
20°FNov 17Dec 1Dec 7Dec 14Dec 23Dec 29Jan 5Jan 18Feb 10
16°FDec 1Dec 8Dec 12Dec 20Dec 26Dec 30Jan 8Jan 23Feb 10

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°F170160154148143138133124116
32°F214203196189184178172166156
28°F276263253244237228220211198
24°F346330316308301290280268251
20°F365365364354345335327315302
16°F365365365365365365364350334

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
97% of years
20°F or colder
68% of years
16°F or colder
29% 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
5,117
Cooling degree days, base 65°F
184
Growing degree days, base 40°F
4,447
Growing degree days, base 45°F
3,043
Growing degree days, base 50°F
1,935
Growing degree days, base 55°F
1,108
Growing degree days, base 60°F
528

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January77704
February64505
March615015
April486048
May3204168
June18416283
July5771479
August5370482
September15022324
October4051107
November626017
December79804

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 13.6 km from Scio. 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 USC00354606 (Lacomb 3 Nne). Public domain.