Washington Parish climate

Washington Parish Frost Dates and Growing Season

NOAA 1991-2020 normals for Bogalusa, 19.3 km from Washington Parish, elevation 100 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Bogalusa. 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 March 2 and the first fall freeze around November 23, a growing season of about 265 days.

Median at 36°F
last March 17, first November 11
Median at 32°F
last March 2, first November 23
Median at 28°F
last February 11, first December 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°FApr 7Apr 1Mar 27Mar 22Mar 17Mar 13Mar 8Mar 2Feb 23
32°FMar 24Mar 17Mar 12Mar 8Mar 2Feb 27Feb 22Feb 14Feb 5
28°FMar 14Mar 5Feb 27Feb 18Feb 11Feb 5Jan 31Jan 23Jan 13
24°FMar 2Feb 14Feb 5Jan 31Jan 28Jan 22Jan 16Jan 9Dec 31
20°FFeb 7Jan 31Jan 27Jan 22Jan 16Jan 12Jan 9Jan 3Dec 28
16°FJan 31Jan 28Jan 23Jan 17Jan 14Jan 11Jan 8Jan 5Jan 2

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°FOct 30Nov 2Nov 5Nov 8Nov 11Nov 15Nov 18Nov 23Dec 1
32°FNov 6Nov 10Nov 15Nov 19Nov 23Nov 28Dec 2Dec 7Dec 18
28°FNov 15Nov 25Dec 1Dec 6Dec 12Dec 19Dec 28Jan 3Jan 13
24°FDec 6Dec 14Dec 24Dec 31Jan 2Jan 7Jan 11Jan 18Feb 1
20°FDec 21Dec 31Jan 1Jan 5Jan 8Jan 11Jan 15Jan 22Jan 31
16°FJan 1Jan 2Jan 6Jan 8Jan 10Jan 14Jan 18Jan 23Jan 30

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°F268259250244238232226219211
32°F298285277271265260253246237
28°F339327316310302295286278264
24°F365365353345336331322311299
20°F365365365365365364354343332
16°F365365365365365365365365360

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
98% of years
24°F or colder
80% of years
20°F or colder
43% of years
16°F or colder
13% 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
1,752
Cooling degree days, base 65°F
2,622
Growing degree days, base 40°F
10,036
Growing degree days, base 45°F
8,294
Growing degree days, base 50°F
6,646
Growing degree days, base 55°F
5,144
Growing degree days, base 60°F
3,797

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January4738120
February32115166
March19243333
April68124507
May5294753
June0459909
July05351,000
August0525990
September1398847
October54173586
November23636278
December40312157

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 19.3 km from Washington Parish. 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 USC00160945 (Bogalusa). Public domain.