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MSU Proxy/Primo Seedhead Timer (GDD 32)
through Tue, Mar. 10. 2026

 

GDD Total: 240 (Base 32) through Tue, Mar. 10, 2026

  

Porter, IN

        

Forecast »

“Flashback” to 2025

3/4

3/5

3/6

3/7

3/8

3/9

3/10

3/11

3/12

3/13

3/14

3/15

3/16

Done

651

Over

501

Target

220

Close

121

Under

0

 

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 32° 56° 22 12 2 0 0
02-16 33° 60° 47 27 7 0 0
02-17 41° 55° 73 43 13 0 0
02-18 45° 62° 104 64 24 3 0
02-19 38° 55° 129 79 29 3 0
02-20 27° 49° 145 85 29 3 0
02-21 25° 29° 150 85 29 3 0
02-22 21° 25° 151 85 29 3 0
02-23 18° 25° 151 85 29 3 0
02-24 17° 37° 157 85 29 3 0
02-25 27° 37° 167 85 29 3 0
02-26 21° 41° 175 85 29 3 0
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-27 29° 61° 198 98 32 3 0
02-28 28° 49° 215 105 32 3 0
03-01 25° 33° 222 105 32 3 0
03-02 22° 43° 233 105 32 3 0
03-03 32° 40° 247 110 32 3 0
03-04 35° 43° 264 117 32 3 0
03-05 42° 47° 287 129 35 3 0
03-06 45° 76° 325 158 53 14 6
03-07 40° 63° 354 177 62 15 6
03-08 34° 61° 380 193 68 15 6
03-09 46° 71° 417 219 85 24 9
03-10 42° 63° 447 240 95 26 9
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-11 40° 54° 472 255 100 26 9
03-12 29° 45° 488 260 100 26 9
03-13 38° 49° 509 272 102 26 9
03-14 30° 46° 525 278 102 26 9
03-15 37° 49° 546 289 103 26 9
03-16 20° 26° 547 289 103 26 9
03-17 14° 32° 548 289 103 26 9
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-15 25° 35° 8 0 0 0 0
02-16 18° 30° 10 0 0 0 0
02-17 1° 16° 10 0 0 0 0
02-18 1° 14° 10 0 0 0 0
02-19 8° 19° 10 0 0 0 0
02-20 4° 24° 10 0 0 0 0
02-21 9° 30° 10 0 0 0 0
02-22 12° 34° 11 0 0 0 0
02-23 22° 42° 21 0 0 0 0
02-24 35° 51° 42 12 1 0 0
02-25 33° 51° 62 22 1 0 0
02-26 32° 47° 80 29 1 0 0
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-27 33° 48° 99 38 1 0 0
02-28 31° 57° 120 49 3 0 0
03-01 18° 37° 126 49 3 0 0
03-02 15° 34° 129 49 3 0 0
03-03 26° 42° 141 51 3 0 0
03-04 40° 48° 163 63 5 0 0
03-05 29° 50° 181 71 5 0 0
03-06 28° 38° 192 72 5 0 0
03-07 31° 39° 205 75 5 0 0
03-08 30° 46° 221 82 5 0 0
03-09 31° 56° 243 93 7 0 0
03-10 37° 65° 272 113 16 1 0
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-11 36° 55° 296 126 19 1 0
03-12 34° 52° 316 137 20 1 0
03-13 31° 63° 342 152 25 1 0
03-14 46° 76° 381 181 44 12 6
03-15 48° 68° 417 207 61 21 9
03-16 30° 43° 432 212 61 21 9
03-17 25° 50° 447 218 61 21 9
03-18 44° 72° 484 244 77 29 13
03-19 36° 65° 512 262 85 29 13
03-20 31° 39° 524 265 85 29 13
03-21 29° 56° 545 275 86 29 13
03-22 32° 49° 563 284 86 29 13
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-23 32° 46° 580 291 86 29 13
03-24 34° 47° 599 300 86 29 13
03-25 29° 45° 614 304 86 29 13
03-26 27° 49° 630 310 86 29 13
03-27 39° 55° 655 326 91 29 13
03-28 46° 77° 695 355 110 41 19
03-29 57° 66° 734 385 130 52 26
03-30 49° 74° 774 415 150 64 33
03-31 33° 47° 792 422 150 64 33
04-01 29° 46° 808 428 150 64 33
04-02 38° 65° 837 448 159 66 33
04-03 43° 63° 868 469 171 69 33
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-04 38° 52° 891 482 173 69 33
04-05 40° 46° 912 492 174 69 33
04-06 35° 45° 930 500 174 69 33
04-07 31° 43° 945 506 174 69 33
04-08 26° 39° 956 506 174 69 33
04-09 31° 41° 970 510 174 69 33
04-10 37° 45° 989 519 174 69 33
04-11 33° 46° 1006 527 174 69 33
04-12 29° 56° 1027 537 175 69 33
04-13 50° 61° 1060 561 188 74 33
04-14 52° 62° 1096 586 203 81 35
04-15 39° 53° 1120 600 207 81 35
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-16 33° 44° 1136 607 207 81 35
04-17 35° 65° 1164 625 215 81 35
04-18 57° 78° 1210 660 241 99 48
04-19 42° 69° 1243 684 254 104 48
04-20 46° 64° 1276 707 267 109 48
04-21 51° 60° 1310 730 281 115 49
04-22 40° 71° 1343 753 294 120 49
04-23 51° 76° 1385 785 316 134 58
04-24 49° 75° 1425 815 336 146 65
04-25 43° 62° 1456 836 347 149 65
04-26 40° 47° 1478 848 349 149 65
04-27 33° 67° 1506 866 357 149 65
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-28 51° 80° 1549 900 381 165 76
04-29 50° 76° 1591 931 402 178 84
04-30 42° 63° 1621 952 412 181 84
05-01 52° 70° 1661 981 432 192 90
05-02 46° 59° 1691 1002 442 195 90
05-03 43° 53° 1717 1018 448 195 90
05-04 44° 48° 1741 1032 452 195 90
05-05 47° 60° 1773 1053 464 198 90
05-06 45° 73° 1810 1080 481 207 94
05-07 46° 71° 1847 1107 498 216 98
05-08 44° 59° 1876 1126 507 217 98
05-09 37° 55° 1900 1140 511 217 98
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-10 40° 71° 1934 1164 525 223 98
05-11 43° 70° 1968 1188 539 229 100
05-12 50° 78° 2010 1221 561 243 109
05-13 60° 72° 2054 1255 586 259 120
05-14 59° 73° 2098 1289 609 275 131
05-15 63° 89° 2152 1333 644 301 152
05-16 62° 84° 2203 1374 675 324 170
05-17 55° 69° 2243 1404 695 336 177
05-18 48° 61° 2276 1426 707 341 177
05-19 45° 56° 2305 1445 716 342 177
05-20 48° 57° 2335 1465 726 344 177
05-21 48° 54° 2364 1484 735 345 177
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-22 45° 53° 2391 1501 742 345 177
05-23 38° 55° 2416 1516 747 345 177
05-24 40° 62° 2445 1535 756 346 177
05-25 51° 63° 2480 1561 771 353 180
05-26 44° 64° 2512 1583 783 357 180
05-27 54° 67° 2551 1611 802 368 185
05-28 53° 60° 2585 1636 816 374 187
05-29 51° 67° 2622 1663 833 383 191
05-30 53° 71° 2662 1693 853 395 198
05-31 47° 61° 2695 1715 866 400 198
06-01 41° 61° 2724 1734 875 401 198
06-02 43° 81° 2764 1764 895 413 205
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-03 65° 87° 2818 1808 929 439 226
06-04 56° 78° 2863 1843 954 456 238
06-05 57° 64° 2901 1872 972 466 243
06-06 60° 70° 2945 1905 996 482 253
06-07 55° 76° 2988 1938 1019 497 264
06-08 61° 81° 3037 1977 1048 518 280
06-09 55° 75° 3080 2010 1071 533 290
06-10 54° 77° 3123 2043 1094 548 300
06-11 61° 88° 3176 2086 1127 573 320
06-12 64° 80° 3226 2127 1157 595 337
06-13 64° 74° 3273 2164 1184 614 351
06-14 63° 71° 3318 2199 1210 632 363
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-15 59° 77° 3364 2235 1235 649 376
06-16 61° 83° 3414 2275 1265 671 393
06-17 69° 90° 3472 2322 1303 701 418
06-18 67° 83° 3525 2366 1336 726 438
06-19 64° 80° 3575 2406 1366 748 455
06-20 66° 84° 3628 2449 1399 773 475
06-21 74° 92° 3689 2500 1440 806 503
06-22 78° 93° 3753 2553 1484 842 533
06-23 77° 93° 3816 2606 1527 877 563
06-24 75° 94° 3878 2659 1569 911 593
06-25 70° 84° 3934 2704 1605 939 615
06-26 75° 91° 3994 2755 1646 972 643
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-27 74° 87° 4053 2804 1684 1002 669
06-28 68° 82° 4106 2847 1718 1028 689
06-29 70° 88° 4164 2894 1755 1057 714
06-30 74° 84° 4221 2941 1792 1086 738
07-01 70° 81° 4274 2985 1825 1111 758
07-02 66° 86° 4328 3029 1859 1137 779
07-03 68° 88° 4384 3075 1895 1165 802
07-04 72° 88° 4442 3122 1933 1195 827
07-05 73° 91° 4502 3173 1974 1228 854
07-06 70° 87° 4559 3220 2010 1256 878
07-07 67° 76° 4609 3259 2040 1278 895
07-08 62° 88° 4662 3302 2073 1303 915
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-09 69° 82° 4715 3346 2106 1328 935
07-10 65° 83° 4768 3388 2139 1353 954
07-11 71° 89° 4825 3436 2177 1383 979
07-12 73° 85° 4882 3483 2214 1412 1003
07-13 69° 81° 4935 3526 2246 1436 1023
07-14 61° 85° 4986 3567 2277 1459 1041
07-15 65° 90° 5042 3612 2313 1487 1063
07-16 72° 90° 5101 3661 2352 1518 1090
07-17 65° 76° 5149 3700 2380 1538 1105
07-18 60° 79° 5197 3738 2408 1558 1120
07-19 69° 81° 5250 3781 2442 1584 1140
07-20 69° 74° 5300 3820 2471 1605 1157
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-21 64° 82° 5351 3861 2502 1628 1175
07-22 65° 82° 5403 3903 2534 1652 1193
07-23 67° 90° 5459 3949 2570 1680 1217
07-24 74° 94° 5521 4001 2612 1714 1246
07-25 72° 81° 5576 4046 2647 1741 1267
07-26 72° 79° 5629 4089 2680 1766 1288
07-27 73° 87° 5687 4137 2718 1796 1312
07-28 75° 88° 5746 4187 2757 1827 1339
07-29 69° 91° 5804 4235 2796 1858 1364
07-30 70° 83° 5859 4280 2830 1884 1386
07-31 62° 75° 5906 4316 2857 1903 1399
08-01 60° 74° 5950 4351 2882 1920 1411
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-02 57° 76° 5995 4385 2906 1936 1423
08-03 57° 77° 6040 4420 2931 1953 1435
08-04 60° 80° 6088 4459 2959 1973 1450
08-05 59° 81° 6136 4497 2988 1994 1465
08-06 61° 83° 6187 4537 3018 2016 1482
08-07 68° 87° 6242 4582 3053 2043 1505
08-08 72° 88° 6300 4630 3091 2073 1530
08-09 71° 89° 6358 4678 3129 2103 1555
08-10 72° 89° 6417 4727 3168 2134 1580
08-11 73° 86° 6474 4774 3205 2163 1605
08-12 71° 88° 6532 4822 3243 2193 1629
08-13 68° 82° 6585 4865 3276 2218 1649
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-14 62° 81° 6634 4904 3305 2239 1666
08-15 64° 88° 6688 4948 3339 2265 1687
08-16 75° 91° 6749 5000 3381 2299 1715
08-17 70° 82° 6803 5044 3415 2325 1736
08-18 69° 84° 6858 5089 3449 2351 1758
08-19 70° 77° 6910 5130 3481 2375 1776
08-20 67° 72° 6957 5168 3509 2395 1791
08-21 61° 74° 7002 5203 3534 2412 1803
08-22 58° 78° 7048 5239 3560 2430 1816
08-23 65° 82° 7100 5280 3591 2453 1835
08-24 59° 73° 7144 5314 3615 2469 1846
08-25 57° 67° 7184 5344 3635 2481 1853
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-26 56° 70° 7225 5375 3656 2494 1861
08-27 50° 74° 7265 5406 3676 2506 1868
08-28 60° 73° 7310 5440 3701 2523 1880
08-29 51° 67° 7347 5468 3718 2532 1884
08-30 56° 73° 7390 5500 3741 2547 1893
08-31 52° 74° 7430 5531 3762 2560 1901
09-01 53° 75° 7473 5563 3784 2574 1910
09-02 55° 77° 7516 5597 3808 2590 1921
09-03 58° 74° 7561 5631 3832 2606 1932
09-04 53° 65° 7598 5658 3849 2615 1937
09-05 55° 68° 7637 5688 3868 2626 1943
09-06 46° 65° 7671 5711 3882 2632 1944
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
09-07 47° 64° 7704 5735 3895 2637 1944
09-08 43° 70° 7739 5759 3910 2644 1946
09-09 46° 75° 7777 5788 3928 2654 1951
09-10 58° 79° 7824 5824 3955 2673 1965
09-11 57° 78° 7870 5860 3981 2691 1977
09-12 54° 81° 7916 5896 4007 2709 1990
09-13 61° 74° 7961 5932 4032 2726 2003
09-14 61° 83° 8011 5972 4062 2748 2020
09-15 61° 82° 8061 6011 4092 2770 2036
09-16 58° 78° 8107 6047 4118 2788 2050
09-17 58° 80° 8154 6084 4145 2807 2064
09-18 57° 83° 8202 6122 4173 2827 2079
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
09-19 61° 87° 8254 6164 4205 2851 2097
09-20 65° 78° 8303 6203 4234 2872 2114
09-21 65° 82° 8354 6245 4265 2895 2132
09-22 65° 79° 8404 6284 4295 2917 2149
09-23 64° 72° 8450 6320 4321 2935 2161
09-24 64° 70° 8495 6355 4346 2952 2173
09-25 59° 70° 8537 6388 4368 2966 2183
09-26 52° 79° 8580 6421 4392 2982 2193
09-27 59° 83° 8629 6460 4420 3002 2209
09-28 59° 78° 8676 6496 4447 3021 2222
09-29 57° 83° 8724 6534 4475 3041 2238
09-30 58° 78° 8770 6571 4501 3059 2251
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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