Danielson climate

Danielson Frost Dates and Growing Season

NOAA 1991-2020 normals for N Foster 1 E, 14 km from Danielson, elevation 630 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for N Foster 1 E. 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 25 and the first fall freeze around October 19, a growing season of about 176 days.

Median at 36°F
last May 7, first October 7
Median at 32°F
last April 25, first October 19
Median at 28°F
last April 12, first October 30

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 21May 16May 13May 9May 7May 5May 2Apr 30Apr 26
32°FMay 9May 4May 1Apr 28Apr 25Apr 23Apr 20Apr 17Apr 13
28°FApr 26Apr 21Apr 17Apr 15Apr 12Apr 9Apr 7Apr 4Apr 1
24°FApr 12Apr 7Apr 4Apr 2Apr 1Mar 30Mar 27Mar 22Mar 17
20°FApr 4Mar 31Mar 29Mar 26Mar 22Mar 19Mar 17Mar 13Mar 8
16°FMar 27Mar 23Mar 20Mar 17Mar 15Mar 12Mar 9Mar 5Feb 27

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

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°F170165160156152148145140134
32°F195189184179176172168162156
28°F217212208204201197193188182
24°F244238232228223220216212206
20°F267260254250246241238231226
16°F289282275271266262258252246

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
6,275
Cooling degree days, base 65°F
509
Growing degree days, base 40°F
4,684
Growing degree days, base 45°F
3,542
Growing degree days, base 50°F
2,556
Growing degree days, base 55°F
1,719
Growing degree days, base 60°F
1,034

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,18901
February1,01201
March890010
April538465
May26121242
June7086467
July9190646
August17155603
September12949373
October4264121
November713024
December1,02303

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 km from Danielson. 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 USC00375270 (N Foster 1 E). Public domain.