horticulture:weather

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Weather

Current Weather

Zone/Region Info

CountySC RegionUSDA ZoneTemperature Range
RichlandCoastal8a(10 to 15 °F/-12.2 to -9.4 °C)
https://planthardiness.ars.usda.gov/
https://hgic.clemson.edu/factsheet/planning-a-garden/

Average Frost Dates

AltitudeLast Spring FrostFirst Fall FrostGrowing Season
223'Mar 24Nov 9229 days
https://www.almanac.com/gardening/frostdates/SC/Columbia
Average Last FrostAverage First Frost
Apr. 1 - Apr. 10Nov. 11 - Nov. 20
https://www.plantmaps.com/interactive-south-carolina-last-frost-date-map.php

Autumn frost freeze dates

https://www.weather.gov/cae/Autumnfrostfreeze.html

Minimum temperature of 36 degrees
Columbia
Average DateOctober 25
Earliest Date10/3/1974
Latest Date11/14/2003
Minimum temperature of 32 degrees
Columbia
Average DateNovember 3
Earliest Date10/4/1974
Latest Date12/10/1978
Minimum temperature of 28 degrees
Columbia
Average DateNovember 16
Earliest Date10/22/1952 & 1974
Latest Date12/19/2011

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How to read these charts for the spring

As the growing season approaches, the days get longer, the weather begins to warm up, and the nights start being less cold. You're still getting frost, but the chance of nightly frosts gets less and less with each passing day.

Eventually, the frost stops, and this is when your tender plants are fully safe.

So, how do you plan for this?

The probabilities on this page help you assess your risk of frost on any given day.

What's a safe temperature for tender plants?

When the nightly temperature falls, frost can form, even above 32°, because the air is colder high above the ground and the frost can form up there and then fall down onto your garden and do some damage, even if it's 36° on the ground.

So many factors come into play, including wind, concrete, houses, trees and other structures, etc etc etc.

Because of all this, you might want to consider 36° as “the danger zone”.

In your average springtime, you have a 90% chance that there will be no 36° nights by April 15.

In other words, you can pretty much count on being safe from frost by that day.

But we want to get those tomatoes in the ground as soon as possible, right?

We see that there's still an 80% chance of 36° on March 20, so we don't dare plant that early.

We wait a few days and by March 30 we are at the 50/50 point. At this point, we are close and we can start watching the weather forecast.

If the upcoming week's forecast doesn't show below 40°, then it's probably okay to risk planting out your plants.

If conditions change and a surprise frost does threaten, there's always things you can do to protect plants from frost.

Spring
Last 16°
Feb 9
Jan 30
Jan 21
Jan 12
Dec 27
Last 20°
Feb 23
Feb 13
Feb 7
Jan 31
Jan 25
Jan 18
Jan 9
Last 24°
Mar 7
Feb 26
Feb 19
Feb 14
Feb 9
Feb 3
Jan 29
Jan 22
Jan 11
Mar 12
Mar 7
Mar 3
Feb 28
Feb 25
Feb 22
Feb 19
Feb 15
Feb 10
Last 32°
Apr 7
Mar 31
Mar 26
Mar 22
Mar 18
Mar 14
Mar 10
Mar 5
Feb 26
Last 36°
Apr 15
Apr 10
Apr 6
Apr 2
Mar 30
Mar 27
Mar 24
Mar 20
Mar 15

How to read these charts for the fall As your growing season comes to an end, the nightly temperatures for Columbia, South Carolina start to go down, and therefore every day that goes by increases the chance that you'll get frost. Your risk of frost really begins around October 26, and by November 23 you're almost certain to have received at least one frost event. The charts on this page show the probabilities of receiving a certain temperature on a certain day. Some examples that might help: You have a small 20% chance of getting 32° by November 1. There is a 50% chance of being hit by a 32° frost starting around November 12 You have a 80% chance of seeing 32° by November 23 Said another way, you have a 1 in 5 chance at making it to that day without a 32° night. In the Fall Temperature 10% 20% 30% 40% 50% 60% 70% 80% 90% First 16° Jan 1 Jan 12 Jan 21 Jan 30 Feb 15 – – – – First 20° Dec 12 Dec 22 Dec 29 Jan 5 Jan 11 Jan 18 Jan 28 – – First 24° Nov 28 Dec 7 Dec 13 Dec 18 Dec 23 Dec 28 Jan 3 Jan 9 Jan 20 First 28° Nov 8 Nov 17 Nov 23 Nov 29 Dec 4 Dec 9 Dec 14 Dec 20 Dec 29 First 32° Oct 26 Nov 1 Nov 5 Nov 9 Nov 12 Nov 15 Nov 19 Nov 23 Nov 29 First 36° Oct 14 Oct 20 Oct 25 Oct 29 Nov 1 Nov 5 Nov 9 Nov 13 Nov 20

Columbia metro

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  • Last modified: 2023/05/12 23:45
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