Sparrow Bush climate

Sparrow Bush Frost Dates and Growing Season

NOAA 1991-2020 normals for Matamoras, 1.1 km from Sparrow Bush, elevation 459 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Matamoras. 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 May 2 and the first fall freeze around October 12, a growing season of about 164 days.

Median at 36°F
last May 14, first October 3
Median at 32°F
last May 2, first October 12
Median at 28°F
last April 20, first October 23

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 28May 23May 20May 17May 14May 11May 8May 3Apr 30
32°FMay 17May 11May 8May 5May 2Apr 30Apr 26Apr 24Apr 20
28°FMay 4Apr 30Apr 26Apr 23Apr 20Apr 17Apr 15Apr 12Apr 8
24°FApr 21Apr 16Apr 12Apr 10Apr 7Apr 5Apr 3Mar 31Mar 27
20°FApr 8Apr 4Apr 2Mar 31Mar 28Mar 25Mar 20Mar 16Mar 10
16°FMar 31Mar 26Mar 23Mar 18Mar 15Mar 12Mar 9Mar 4Feb 28

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

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°F160155150146142138134130124
32°F181175171167164160156151144
28°F205199194190185181177172165
24°F231224220216212208203198191
20°F258250245240236232227222216
16°F283276269264259254249243237

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
6,530
Cooling degree days, base 65°F
484
Growing degree days, base 40°F
4,557
Growing degree days, base 45°F
3,460
Growing degree days, base 50°F
2,506
Growing degree days, base 55°F
1,687
Growing degree days, base 60°F
1,007

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,23800
February1,06700
March92209
April559363
May26125248
June6096486
July10173628
August20142587
September13142366
October4573105
November755012
December1,05102

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 1.1 km from Sparrow Bush. 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 USC00365470 (Matamoras). Public domain.