Weiser climate

Weiser Frost Dates and Growing Season

NOAA 1991-2020 normals for Weiser, 0.6 km from Weiser, elevation 2120 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Weiser. 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 23 and the first fall freeze around October 13, a growing season of about 174 days.

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

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 1Oct 4Oct 6Oct 9Oct 12Oct 16
32°FOct 1Oct 5Oct 8Oct 11Oct 13Oct 16Oct 19Oct 22Oct 27
28°FOct 12Oct 16Oct 19Oct 23Oct 25Oct 28Oct 31Nov 3Nov 7
24°FOct 20Oct 25Oct 30Nov 1Nov 5Nov 8Nov 12Nov 16Nov 23
20°FOct 31Nov 5Nov 10Nov 14Nov 18Nov 21Nov 24Nov 28Dec 5
16°FNov 10Nov 17Nov 22Nov 26Nov 29Dec 2Dec 7Dec 15Dec 26

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°F169162157152148144139133125
32°F197188182178174170165159151
28°F229220214209204199194187180
24°F262254247242237232226219208
20°F295285278271267262257251242
16°F324313306299292286280272261

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
5,616
Cooling degree days, base 65°F
1,008
Growing degree days, base 40°F
5,481
Growing degree days, base 45°F
4,265
Growing degree days, base 50°F
3,215
Growing degree days, base 55°F
2,338
Growing degree days, base 60°F
1,603

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,10500
February83000
March626019
April409197
May17943334
June45148554
July3400862
August6329787
September8986449
October4252109
November80204
December1,09600

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 0.6 km from Weiser. 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 USC00109638 (Weiser). Public domain.