Probability of a hard frost or freeze in the spring for some southwest Michigan fruit sites
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EmailA late spring can be a blessing in disguise. Late growth may mean fruit growers will avoid spring freeze injury.
Frosts and freezes in the spring are a hazard to fruit growers because freezing temperatures can kill actively growing shoots and flowers, destroying all or part of the fruit potential for the year. As overwintering buds develop, they become less and less resistant to cold (see the Michigan State University Extension article “Freeze damage depends on tree fruit stage of development”).
At bloom, fruit tree blossoms suffer damage just below freezing at about 28 degrees Fahrenheit. Because it has to get below freezing to cause injury, 28 F is often called a hard frost or a hard freeze to denote that the temperature was below freezing.
In 2012, fruit trees bloomed a month early and the normal freezes of April devastated the Michigan’s tree fruit industries. In 2013, we are one or two weeks behind normal development and tree fruit are only now entering the stage when hard freezes can cause damage. In many parts of southwest Michigan, there is only a 25 percent chance or less of a damaging freeze this spring. The possibility of a freeze continues to drop into early May. This means there is an excellent chance that there will be no freeze damage to fruit crops because the cool April delayed growth.
The National Weather Service has calculated the probability of a freeze for many of their long-term weather stations using data from 1951 to 1980. The table below is arranged from north to south. Sites located away from Lake Michigan show the approximate distance to the lake. Sites near Lake Michigan show no distance. In the table, 10 percent means there is a 10 percent chance of a freeze occurring on or after that date in the spring. Many gardeners worry about the last date when a temperature of 32 F will not occur. For more information on frost-free dates, see “Frost free dates: When is the last day my garden will get a frost?”
Probability of indicated temperature or lower occurring on or before date in spring for southwest Michigan sites (1951-1980 data)
|
Holland - lakeshore |
|||||
|
Temperature |
90% |
75% |
50% |
25% |
10% |
|
32 |
April 24 |
May 1 |
May 9 |
May 17 |
May 24 |
|
30 |
April 17 |
April 24 |
May 2 |
May 10 |
May 17 |
|
28 |
April 12 |
April 19 |
April 27 |
May 5 |
May 12 |
|
Allegan - 20 miles inland |
|||||
|
32 |
April 23 |
April 30 |
May 8 |
May 16 |
May 23 |
|
30 |
April 17 |
April 24 |
May 2 |
May 10 |
May 17 |
|
28 |
April 7 |
April 14 |
April 22 |
April 30 |
May 7 |
|
South Haven - lakeshore |
|||||
|
32 |
April 20 |
April 27 |
May 5 |
May 13 |
May 20 |
|
30 |
April 12 |
April 19 |
April 27 |
May 5 |
May 13 |
|
28 |
April 6 |
April 13 |
April 21 |
April 29 |
May 5 |
|
Bloomingdale - 15 miles inland |
|||||
|
32 |
April 26 |
May 3 |
May 11 |
May 19 |
May 26 |
|
30 |
April 19 |
April 26 |
May 4 |
May 12 |
May 19 |
|
28 |
April 11 |
April 18 |
April 26 |
May 4 |
May 11 |
|
Paw Paw - 23 miles inland |
|||||
|
32 |
April 25 |
May 2 |
May 10 |
May 18 |
May 25 |
|
30 |
April 22 |
April 29 |
May 7 |
May 15 |
May 22 |
|
28 |
April 16 |
April 23 |
May 1 |
May 9 |
May 16 |
|
Kalamazoo - 49 miles inland |
|||||
|
32 |
April 24 |
May 1 |
May 9 |
May 17 |
May 24 |
|
30 |
April 18 |
April 25 |
May 3 |
May 11 |
May 18 |
|
28 |
April 9 |
April 16 |
April 24 |
May 2 |
May 9 |
|
St. Joseph - lakeshore |
|||||
|
32 |
April 10 |
April 17 |
April 25 |
May 3 |
May 10 |
|
30 |
April 4 |
April 11 |
April 19 |
April 27 |
May 4 |
|
28 |
March 25 |
April 1 |
April 9 |
April 17 |
April 24 |
|
Eau Claire - 12 miles inland |
|||||
|
32 |
April 19 |
April 26 |
May 4 |
May 12 |
May 19 |
|
30 |
April 12 |
April 19 |
April 27 |
May 5 |
May 12 |
|
28 |
April 5 |
April 12 |
April 20 |
April 28 |
May 5 |
Additional information
