Historical Climate Data

Growing Season Summary
Station: 478027 SPOONER EXPERMNT FARM, WI

Growing Degree Day Averages
Derived from 1971-2000 Data

 

Element JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ANN
GDD
Base 40		 0 2 30 192 525 750 915 845 552 252 34 1 4102
GDD
Base 45		 0 0 11 108 379 601 761 690 407 147 13 0 3119
GDD
Base 50		 0 0 4 55 248 452 606 535 272 73 4 0 2250
GDD
Base 55		 0 0 1 24 144 308 451 382 159 29 1 0 1503
GDD
Base 60		 0 0 0 9 72 182 300 238 80 9 0 0 892
MGDD*
Base 50		 0 1 23 140 344 484 603 550 340 154 20 0 2661

*Modified Growing Degree Days: Base 50 Ceiling 86.

Growing Season Summary
Derived from 1971-2000 Averages

  Date of Last Spring Occurrence Date of First Fall Occurrence
Base
Temp
°F		 Median Early 90% 10% Late Median Early 90% 10% Late
32 5/20 4/11 5/03 6/07 6/24 9/23 8/28 9/09 10/05 10/10
30 5/17 4/11 4/28 5/29 6/11 9/29 9/01 9/19 10/10 10/14
28 5/07 4/11 4/23 5/20 5/21 10/02 9/01 9/21 10/11 10/16
24 4/22 3/25 4/09 5/07 5/10 10/15 9/22 10/03 11/01 11/10
20 4/12 3/24 4/03 4/23 5/06 11/01 10/02 10/13 11/12 11/16
16 4/06 3/15 3/22 4/14 4/21 11/04 10/02 10/19 11/24 12/07

Length of Growing Season (Days)
Derived from 1971-2000 Averages

Base
Temp
°F		 Median Shortest 10% 90% Longest
32 124 91 104 147 167
30 138 104 118 156 182
28 147 118 127 165 182
24 177 139 148 206 212
20 200 161 175 219 233
16 216 177 193 238 258