Please Note

The GDD models have only been “ground-truthed” in the Great Lakes region. Use of models outside of this region, including the North East, Great Plains and Transition Zones, should be used with caution. We do not recommend the GDD models we use for the mid/southern transition zone and southern states.

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MSU Proxy/Primo Seedhead Timer (GDD 32)
through Tue, Jul. 21. 2026

 
  

IA

        

Generously Supported By:



Tabular Data

Daily GDD accumulation for various base temperature models in 2025 & 2026

2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-15 36° 64° 28 18 8 0 0
02-16 43° 68° 62 42 22 6 1
02-17 40° 64° 92 62 32 8 1
02-18 43° 61° 122 82 42 10 1
02-19 26° 38° 132 82 42 10 1
02-20 10° 24° 132 82 42 10 1
02-21 9° 23° 132 82 42 10 1
02-22 7° 22° 132 82 42 10 1
02-23 -2° 20° 132 82 42 10 1
02-24 15° 40° 137 82 42 10 1
02-25 24° 34° 144 82 42 10 1
02-26 24° 52° 160 88 42 10 1
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-27 33° 65° 187 105 49 10 1
02-28 24° 40° 197 105 49 10 1
03-01 18° 35° 202 105 49 10 1
03-02 28° 47° 218 111 49 10 1
03-03 38° 42° 235 119 49 10 1
03-04 39° 51° 258 131 52 10 1
03-05 42° 58° 286 149 59 10 1
03-06 46° 70° 322 175 75 18 4
03-07 32° 50° 341 184 75 18 4
03-08 35° 69° 371 204 85 20 4
03-09 49° 74° 410 234 105 32 10
03-10 40° 61° 439 252 113 32 10
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-11 32° 48° 457 260 113 32 10
03-12 25° 55° 475 268 113 32 10
03-13 33° 54° 496 279 115 32 10
03-14 32° 54° 517 290 116 32 10
03-15 20° 45° 527 291 116 32 10
03-16 6° 20° 527 291 116 32 10
03-17 6° 25° 527 291 116 32 10
03-18 24° 66° 551 304 119 32 10
03-19 37° 75° 585 328 133 38 11
03-20 52° 79° 628 362 156 54 22
03-21 52° 90° 677 401 186 75 38
03-22 36° 73° 710 423 198 79 38
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-23 27° 52° 727 431 198 79 38
03-24 36° 61° 754 447 205 79 38
03-25 42° 78° 792 475 222 89 43
03-26 45° 71° 828 501 239 97 46
03-27 30° 50° 846 509 239 97 46
03-28 21° 59° 864 518 239 97 46
03-29 40° 69° 897 540 251 102 46
03-30 46° 88° 942 575 276 119 58
03-31 45° 69° 977 600 292 126 60
04-01 40° 49° 1000 613 294 126 60
04-02 41° 54° 1025 629 300 126 60
04-03 37° 50° 1047 641 302 126 60
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-04 37° 44° 1066 649 302 126 60
04-05 33° 61° 1091 664 307 126 60
04-06 38° 50° 1113 676 309 126 60
04-07 34° 44° 1130 683 309 126 60
04-08 40° 74° 1165 708 323 133 62
04-09 42° 54° 1191 724 330 133 62
04-10 38° 54° 1215 738 333 133 62
04-11 42° 58° 1243 756 342 133 62
04-12 59° 71° 1286 789 365 148 72
04-13 61° 81° 1335 828 394 169 88
04-14 64° 86° 1388 871 427 194 108
04-15 59° 72° 1431 905 450 210 119
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-16 50° 79° 1474 937 473 224 128
04-17 48° 80° 1516 969 495 238 137
04-18 33° 52° 1537 980 495 238 137
04-19 36° 57° 1561 994 499 238 137
04-20 34° 70° 1591 1014 509 240 137
04-21 59° 84° 1640 1054 539 262 154
04-22 60° 78° 1687 1090 566 280 168
04-23 58° 74° 1731 1124 590 296 178
04-24 45° 62° 1762 1146 601 300 178
04-25 45° 73° 1799 1173 618 309 182
04-26 55° 72° 1841 1204 640 322 191
04-27 50° 70° 1879 1232 658 332 196
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-28 44° 56° 1908 1251 666 333 196
04-29 43° 59° 1937 1270 675 334 196
04-30 44° 55° 1965 1288 683 334 196
05-01 38° 57° 1990 1303 689 334 196
05-02 35° 64° 2018 1321 696 334 196
05-03 51° 75° 2059 1352 717 347 204
05-04 49° 81° 2102 1385 740 362 214
05-05 45° 61° 2133 1406 751 365 214
05-06 40° 57° 2159 1422 758 365 214
05-07 41° 68° 2191 1444 770 369 214
05-08 45° 75° 2229 1473 788 379 220
05-09 46° 72° 2266 1500 805 388 223
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-10 40° 72° 2300 1523 819 394 224
05-11 46° 76° 2339 1552 838 405 230
05-12 61° 78° 2387 1590 865 425 245
05-13 50° 76° 2428 1621 887 438 253
05-14 50° 78° 2470 1653 909 452 262
05-15 56° 87° 2520 1693 938 474 279
05-16 60° 80° 2568 1731 966 494 294
05-17 63° 82° 2618 1771 996 516 311
05-18 63° 78° 2666 1809 1025 536 326
05-19 52° 65° 2703 1836 1041 545 330
05-20 43° 61° 2733 1856 1051 547 330
05-21 52° 63° 2768 1881 1067 554 332
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-22 55° 69° 2808 1911 1087 566 339
05-23 60° 73° 2852 1946 1111 582 350
05-24 52° 83° 2898 1981 1136 600 363
05-25 63° 85° 2950 2023 1168 624 382
05-26 61° 88° 3002 2065 1201 648 401
05-27 60° 88° 3054 2107 1232 672 420
05-28 64° 85° 3107 2150 1265 697 440
05-29 65° 83° 3159 2192 1297 721 459
05-30 68° 78° 3210 2233 1329 744 477
05-31 64° 83° 3262 2275 1360 768 496
06-01 65° 87° 3316 2319 1394 794 517
06-02 62° 82° 3366 2359 1424 816 534
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-03 58° 83° 3414 2397 1453 836 549
06-04 65° 84° 3466 2440 1485 860 569
06-05 67° 84° 3520 2483 1519 886 589
06-06 68° 88° 3576 2529 1555 914 612
06-07 71° 79° 3629 2572 1587 939 632
06-08 71° 85° 3685 2618 1623 967 655
06-09 71° 91° 3744 2667 1663 998 681
06-10 69° 84° 3799 2712 1698 1025 703
06-11 64° 79° 3849 2752 1727 1047 720
06-12 57° 82° 3896 2790 1755 1066 734
06-13 62° 78° 3944 2828 1783 1086 750
06-14 56° 72° 3986 2860 1805 1100 758
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-15 52° 79° 4030 2893 1828 1116 769
06-16 61° 77° 4076 2930 1855 1134 783
06-17 61° 83° 4127 2970 1885 1157 800
06-18 62° 76° 4174 3007 1913 1176 814
06-19 54° 80° 4219 3043 1938 1193 826
06-20 53° 80° 4264 3077 1962 1210 838
06-21 61° 69° 4307 3110 1985 1225 848
06-22 55° 77° 4350 3144 2009 1240 859
06-23 57° 80° 4397 3180 2036 1259 872
06-24 65° 84° 4449 3223 2068 1283 891
06-25 62° 78° 4498 3261 2096 1304 907
06-26 67° 79° 4549 3302 2127 1327 925
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-27 65° 78° 4598 3342 2157 1348 941
06-28 73° 91° 4658 3391 2197 1380 968
06-29 76° 92° 4720 3443 2239 1414 997
06-30 78° 93° 4783 3496 2282 1449 1027
07-01 80° 91° 4847 3550 2325 1485 1058
07-02 77° 91° 4909 3602 2367 1519 1087
07-03 65° 85° 4962 3645 2401 1544 1107
07-04 68° 85° 5016 3690 2435 1570 1129
07-05 70° 85° 5072 3735 2471 1598 1151
07-06 68° 86° 5127 3780 2506 1625 1173
07-07 68° 89° 5184 3827 2542 1654 1197
07-08 70° 91° 5242 3875 2580 1684 1222
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-09 69° 84° 5296 3920 2615 1710 1244
07-10 70° 83° 5351 3964 2649 1737 1265
07-11 68° 86° 5406 4009 2685 1764 1287
07-12 63° 88° 5459 4052 2718 1789 1307
07-13 65° 90° 5514 4098 2753 1816 1330
07-14 66° 92° 5571 4145 2790 1845 1353
07-15 69° 91° 5629 4192 2828 1875 1378
07-16 71° 91° 5688 4241 2866 1906 1404
07-17 72° 91° 5747 4290 2906 1937 1430
07-18 72° 92° 5807 4340 2946 1969 1457
07-19 66° 88° 5862 4385 2981 1996 1479
07-20 73° 97° 5925 4438 3024 2031 1509
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-21 69° 81° 5977 4481 3056 2055 1529
07-22 61° 78° 6025 4518 3083 2075 1543
07-23 60° 79° 6072 4556 3111 2094 1557
07-24 66° 75° 6121 4594 3139 2115 1573
07-25 70° 92° 6180 4643 3178 2146 1599
07-26 76° 99° 6245 4699 3224 2183 1631
07-27 80° 95° 6311 4754 3270 2221 1664
07-28 73° 86° 6368 4802 3307 2250 1689
07-29 67° 88° 6424 4847 3343 2278 1711
07-30 68° 87° 6480 4893 3379 2306 1734
07-31 68° 79° 6532 4935 3410 2330 1753
08-01 66° 81° 6583 4977 3442 2353 1772
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-02 65° 85° 6637 5020 3475 2379 1792
08-03 65° 85° 6690 5063 3508 2404 1812
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-15 17° 27° 0 0 0 0 0
02-16 3° 15° 0 0 0 0 0
02-17 -3° 4° 0 0 0 0 0
02-18 -11° 3° 0 0 0 0 0
02-19 -3° 8° 0 0 0 0 0
02-20 -7° 13° 0 0 0 0 0
02-21 -2° 20° 0 0 0 0 0
02-22 13° 36° 3 0 0 0 0
02-23 24° 60° 22 10 0 0 0
02-24 41° 61° 51 28 9 1 0
02-25 32° 60° 75 42 13 1 0
02-26 38° 54° 99 57 17 1 0
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-27 37° 55° 123 71 21 1 0
02-28 34° 59° 148 85 25 1 0
03-01 20° 32° 151 85 25 1 0
03-02 16° 48° 161 85 25 1 0
03-03 33° 63° 187 101 31 1 0
03-04 39° 56° 213 117 37 1 0
03-05 26° 34° 221 117 37 1 0
03-06 21° 43° 231 117 37 1 0
03-07 31° 38° 243 119 37 1 0
03-08 25° 51° 259 125 37 1 0
03-09 29° 63° 283 139 41 1 0
03-10 35° 79° 317 163 56 7 2
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-11 36° 57° 342 178 60 7 2
03-12 30° 69° 369 195 68 7 2
03-13 38° 76° 405 221 83 15 4
03-14 53° 80° 449 255 107 31 16
03-15 34° 52° 470 266 108 31 16
03-16 25° 47° 485 271 108 31 16
03-17 33° 77° 517 293 121 36 16
03-18 44° 78° 556 322 140 47 21
03-19 33° 56° 578 334 142 47 21
03-20 28° 49° 595 341 142 47 21
03-21 38° 59° 621 357 148 47 21
03-22 26° 61° 643 369 150 47 21
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-23 39° 54° 667 383 154 47 21
03-24 29° 54° 687 393 154 47 21
03-25 36° 58° 712 408 159 47 21
03-26 30° 64° 737 423 164 47 21
03-27 47° 70° 773 449 181 55 25
03-28 50° 80° 817 483 204 70 35
03-29 56° 76° 861 517 228 86 46
03-30 35° 61° 887 533 234 86 46
03-31 31° 49° 905 541 234 86 46
04-01 33° 48° 923 549 234 86 46
04-02 46° 68° 959 575 249 94 48
04-03 36° 53° 981 587 252 94 48
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-04 36° 47° 1001 597 252 94 48
04-05 36° 47° 1020 606 252 94 48
04-06 24° 57° 1039 615 252 94 48
04-07 33° 45° 1056 622 252 94 48
04-08 23° 54° 1073 629 252 94 48
04-09 40° 66° 1104 650 263 97 48
04-10 42° 61° 1133 669 273 99 48
04-11 45° 57° 1162 688 282 99 48
04-12 37° 71° 1195 711 294 104 48
04-13 54° 78° 1239 745 318 120 59
04-14 45° 64° 1271 767 331 124 59
04-15 38° 63° 1299 785 339 125 59
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-16 38° 75° 1334 810 353 131 61
04-17 58° 76° 1378 844 378 148 73
04-18 49° 66° 1414 870 394 156 75
04-19 39° 57° 1440 886 400 156 75
04-20 43° 52° 1466 902 405 156 75
04-21 45° 68° 1500 926 419 162 77
04-22 52° 70° 1539 955 438 173 83
04-23 56° 77° 1584 990 463 190 95
04-24 56° 72° 1626 1022 485 204 104
04-25 52° 62° 1661 1047 500 211 106
04-26 42° 65° 1692 1068 511 214 106
04-27 48° 66° 1727 1093 526 221 108
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-28 59° 81° 1775 1131 554 241 123
04-29 48° 73° 1813 1159 573 251 128
04-30 45° 67° 1848 1184 587 258 129
05-01 53° 66° 1885 1211 605 267 134
05-02 45° 57° 1914 1230 614 268 134
05-03 44° 61° 1945 1251 624 271 134
05-04 40° 71° 1979 1275 638 277 135
05-05 46° 73° 2016 1302 656 286 139
05-06 47° 76° 2055 1331 675 297 146
05-07 53° 80° 2100 1366 699 314 157
05-08 52° 73° 2141 1397 720 327 165
05-09 46° 75° 2179 1425 739 337 171
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-10 51° 86° 2226 1462 765 356 184
05-11 55° 83° 2273 1499 792 375 198
05-12 49° 83° 2316 1532 816 390 209
05-13 57° 83° 2365 1571 844 411 224
05-14 60° 85° 2415 1611 875 433 242
05-15 64° 80° 2465 1651 905 455 259
05-16 55° 74° 2508 1684 927 470 268
05-17 48° 66° 2543 1709 943 477 270
05-18 39° 74° 2578 1734 957 484 272
05-19 53° 65° 2615 1761 975 493 277
05-20 50° 63° 2650 1786 989 500 278
05-21 48° 59° 2681 1807 1001 503 278
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-22 43° 61° 2711 1827 1011 505 278
05-23 43° 67° 2745 1851 1024 511 279
05-24 54° 67° 2783 1879 1043 521 284
05-25 56° 67° 2823 1909 1062 533 291
05-26 49° 69° 2860 1936 1080 542 295
05-27 55° 65° 2898 1964 1098 552 300
05-28 55° 66° 2937 1993 1116 563 306
05-29 52° 69° 2975 2021 1134 573 311
05-30 52° 79° 3019 2055 1158 589 322
05-31 54° 83° 3065 2091 1185 607 335
06-01 58° 82° 3113 2129 1212 627 350
06-02 59° 87° 3164 2170 1243 650 367
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-03 57° 75° 3208 2204 1267 666 379
06-04 52° 74° 3249 2235 1288 679 387
06-05 55° 77° 3293 2269 1312 695 398
06-06 63° 79° 3342 2308 1341 716 413
06-07 65° 71° 3388 2344 1367 734 427
06-08 58° 71° 3430 2376 1389 748 436
06-09 55° 69° 3470 2406 1409 760 443
06-10 50° 85° 3515 2441 1435 777 455
06-11 61° 94° 3571 2487 1470 805 478
06-12 66° 86° 3625 2531 1504 831 499
06-13 63° 84° 3677 2573 1536 855 518
06-14 66° 89° 3732 2618 1572 882 540
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-15 67° 83° 3786 2662 1605 908 561
06-16 66° 88° 3841 2707 1640 935 583
06-17 65° 78° 3890 2746 1670 956 599
06-18 64° 77° 3939 2785 1698 977 614
06-19 60° 86° 3989 2825 1729 999 632
06-20 70° 91° 4048 2874 1767 1030 658
06-21 80° 96° 4114 2930 1813 1068 691
06-22 77° 94° 4177 2983 1857 1103 721
06-23 73° 92° 4238 3034 1897 1136 749
06-24 70° 78° 4290 3076 1929 1160 768
06-25 71° 88° 4347 3123 1967 1189 792
06-26 71° 88° 4405 3171 2004 1219 817
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-27 64° 84° 4457 3213 2037 1243 836
06-28 69° 90° 4515 3261 2074 1273 861
06-29 71° 83° 4570 3306 2109 1300 883
06-30 69° 83° 4624 3350 2143 1326 904
07-01 64° 84° 4676 3392 2175 1350 923
07-02 64° 82° 4727 3433 2207 1373 941
07-03 68° 92° 4785 3481 2244 1403 966
07-04 73° 90° 4844 3530 2284 1434 992
07-05 72° 84° 4901 3577 2320 1463 1015
07-06 69° 86° 4956 3622 2356 1490 1038
07-07 66° 86° 5011 3667 2390 1517 1059
07-08 66° 83° 5063 3709 2423 1541 1079
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-09 66° 87° 5118 3754 2457 1568 1101
07-10 70° 87° 5175 3801 2494 1597 1125
07-11 68° 78° 5226 3842 2525 1620 1143
07-12 66° 79° 5276 3882 2556 1642 1160
07-13 60° 81° 5325 3921 2584 1663 1176
07-14 64° 87° 5378 3964 2618 1688 1196
07-15 68° 87° 5434 4010 2653 1716 1219
07-16 70° 83° 5488 4054 2688 1742 1240
07-17 61° 73° 5533 4089 2713 1759 1252
07-18 60° 81° 5582 4128 2742 1780 1268
07-19 69° 86° 5638 4174 2778 1808 1291
07-20 71° 86° 5694 4220 2814 1836 1314
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-21 74° 83° 5751 4267 2850 1865 1338
07-22 72° 88° 5809 4315 2888 1895 1363
07-23 76° 91° 5870 4366 2929 1928 1391
07-24 70° 83° 5924 4410 2964 1954 1412
07-25 71° 83° 5980 4456 2999 1982 1434
07-26 73° 86° 6037 4503 3036 2011 1459
07-27 71° 92° 6097 4553 3076 2043 1485
07-28 68° 90° 6153 4599 3113 2071 1509
07-29 70° 92° 6212 4648 3151 2102 1535
07-30 68° 80° 6264 4690 3184 2126 1554
07-31 65° 76° 6313 4729 3212 2147 1570
08-01 58° 74° 6357 4763 3236 2163 1581
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-02 59° 77° 6403 4799 3262 2181 1594
08-03 57° 75° 6447 4833 3287 2197 1605
08-04 61° 77° 6494 4870 3314 2216 1619
08-05 60° 82° 6543 4909 3343 2237 1635
08-06 67° 82° 6595 4951 3375 2261 1654
08-07 70° 84° 6650 4996 3410 2288 1676
08-08 72° 90° 6709 5045 3449 2319 1702
08-09 73° 83° 6765 5091 3485 2347 1725
08-10 71° 83° 6820 5136 3520 2374 1747
08-11 66° 80° 6871 5177 3551 2397 1765
08-12 69° 83° 6925 5221 3585 2423 1786
08-13 63° 81° 6975 5261 3614 2445 1803
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-14 64° 84° 7027 5303 3646 2469 1822
08-15 68° 91° 7085 5351 3684 2499 1846
08-16 74° 93° 7146 5402 3725 2532 1875
08-17 73° 94° 7207 5453 3767 2565 1903
08-18 73° 87° 7265 5501 3804 2595 1928
08-19 70° 87° 7322 5548 3841 2624 1952
08-20 69° 86° 7377 5593 3877 2651 1974
08-21 66° 82° 7429 5635 3909 2675 1993
08-22 61° 83° 7479 5675 3938 2697 2010
08-23 63° 74° 7525 5711 3965 2715 2023
08-24 54° 73° 7567 5743 3986 2729 2032
08-25 49° 72° 7605 5771 4005 2739 2037
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-26 47° 75° 7645 5801 4024 2751 2044
08-27 57° 81° 7691 5837 4051 2769 2057
08-28 56° 82° 7739 5875 4078 2789 2071
08-29 58° 83° 7787 5913 4107 2809 2087
08-30 61° 83° 7838 5954 4137 2832 2104
08-31 66° 76° 7886 5992 4166 2852 2120
09-01 63° 77° 7934 6030 4194 2872 2135
09-02 54° 80° 7979 6065 4219 2889 2147
09-03 54° 71° 8020 6096 4239 2902 2155
09-04 44° 72° 8056 6122 4255 2910 2158
09-05 51° 66° 8093 6149 4272 2919 2162
09-06 44° 67° 8126 6172 4285 2924 2162
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
09-07 42° 74° 8162 6198 4301 2932 2165
09-08 50° 80° 8205 6231 4325 2947 2175
09-09 58° 78° 8251 6267 4350 2965 2188
09-10 58° 84° 8300 6306 4379 2986 2204
09-11 58° 88° 8351 6347 4410 3009 2221
09-12 65° 87° 8404 6390 4444 3034 2242
09-13 66° 97° 8464 6440 4484 3066 2269
09-14 67° 91° 8521 6487 4521 3095 2293
09-15 69° 91° 8579 6535 4559 3125 2318
09-16 67° 88° 8635 6581 4594 3153 2341
09-17 65° 77° 8684 6620 4623 3174 2357
09-18 63° 75° 8731 6657 4650 3193 2371
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
09-19 64° 79° 8780 6696 4680 3214 2387
09-20 59° 74° 8825 6731 4704 3231 2399
09-21 56° 79° 8870 6766 4730 3248 2411
09-22 63° 85° 8922 6808 4762 3272 2430
09-23 61° 73° 8968 6844 4787 3290 2443
09-24 60° 79° 9015 6881 4814 3309 2457
09-25 53° 80° 9059 6915 4839 3325 2468
09-26 55° 87° 9109 6955 4868 3347 2484
09-27 57° 86° 9158 6994 4897 3368 2501
09-28 53° 85° 9205 7031 4925 3387 2515
09-29 60° 88° 9257 7073 4956 3411 2534
09-30 57° 85° 9306 7112 4985 3432 2550
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55

 

Latest Updates

February 16th, 2026Welcome to the 2026 GDD Tracking Season

Although Punxsutawney Phil saw his shadow predicting six more weeks of winter, GDDTracker will start counting on February 15. Spring is when GDDTracker receives the most attention for alerting turfgrass managers of optimal application timing windows for suppressing annual bluegrass seedheads and crabgrass preemergence applications. As spring turns to summer, there are several models that may be helpful throughout the season including the early season dollar spot DMI timer and the Smith-Kerns dollar spot prediction model. To learn about all the available models, click on the "About" tab at the top of the screen. Thanks for your continued support and use of GDDTracker and best wishes for a successful 2026!


 

March 18th, 2024Timing crabgrass preemergence applications in spring

Don't miss this update from from Kevin Frank regarding timing of crabgrass preemergence herbicides.


 

 

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