Cascade Valley climate

Cascade Valley Frost Dates and Growing Season

NOAA 1991-2020 normals for Moses Lake Grant CO AP, 8.1 km from Cascade Valley, elevation 1196 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Moses Lake Grant CO AP. 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 27 and the first fall freeze around October 8, a growing season of about 165 days.

Median at 36°F
last May 9, first September 29
Median at 32°F
last April 27, first October 8
Median at 28°F
last April 10, 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 23May 18May 14May 11May 9May 6May 3Apr 30Apr 27
32°FMay 11May 6May 2Apr 30Apr 27Apr 24Apr 21Apr 16Apr 10
28°FApr 30Apr 23Apr 18Apr 14Apr 10Apr 6Apr 1Mar 29Mar 21
24°FApr 10Apr 2Mar 29Mar 23Mar 16Mar 12Mar 7Mar 3Feb 25
20°FMar 19Mar 11Mar 4Feb 28Feb 25Feb 20Feb 15Feb 9Jan 31
16°FMar 4Feb 26Feb 20Feb 13Feb 7Feb 2Jan 27Jan 16Jan 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 17Sep 21Sep 24Sep 27Sep 29Oct 1Oct 2Oct 5Oct 10
32°FSep 29Oct 1Oct 3Oct 5Oct 8Oct 11Oct 15Oct 18Oct 23
28°FOct 5Oct 11Oct 15Oct 17Oct 20Oct 23Oct 27Oct 30Nov 5
24°FOct 17Oct 21Oct 25Oct 29Nov 1Nov 3Nov 7Nov 12Nov 18
20°FOct 24Oct 30Nov 3Nov 8Nov 12Nov 16Nov 20Nov 24Nov 30
16°FNov 2Nov 10Nov 16Nov 22Nov 26Nov 30Dec 4Dec 11Dec 22

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°F159153149144141137133128122
32°F186179174170165161157152146
28°F216207201196191187183177170
24°F255245237230225220213205196
20°F291280272266260255249242231
16°F330316305297291284276267257

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
99% 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
5,791
Cooling degree days, base 65°F
676
Growing degree days, base 40°F
4,989
Growing degree days, base 45°F
3,791
Growing degree days, base 50°F
2,772
Growing degree days, base 55°F
1,921
Growing degree days, base 60°F
1,220

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,08200
February83000
March673010
April436179
May19627302
June5995486
July6268727
August9232688
September11753388
October471186
November82405
December1,09000

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 8.1 km from Cascade Valley. 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 USW00024110 (Moses Lake Grant CO AP). Public domain.