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Relative Flowering Times for Broadleaf Weeds (GDD 50)
through Wed, Jun. 3. 2026

 

GDD Total: 546 (Base 50) through Wed, Jun. 3, 2026

  

IL

        

Forecast »

“Flashback” to 2025

6/3

6/4

6/5

6/6

6/7

6/8

6/9

6/10

6/11

6/12

6/13

6/14

6/15

Late Season (Biennials and Perennials)

1401

Mid Season and Late Season (SA and Perennials)

601

Mid Season (Perennials)

201

Early and Mid Season (WA and Perennials)

21

Early Season (WA)

5

 

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 30° 59° 23 13 3 0 0
02-16 34° 64° 50 30 10 0 0
02-17 38° 52° 73 43 13 0 0
02-18 44° 60° 103 63 23 2 0
02-19 34° 55° 126 76 26 2 0
02-20 29° 39° 138 78 26 2 0
02-21 26° 28° 143 78 26 2 0
02-22 18° 26° 143 78 26 2 0
02-23 17° 28° 143 78 26 2 0
02-24 17° 34° 147 78 26 2 0
02-25 23° 33° 153 78 26 2 0
02-26 14° 40° 158 78 26 2 0
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-27 26° 63° 180 90 29 2 0
02-28 23° 45° 193 93 29 2 0
03-01 9° 31° 193 93 29 2 0
03-02 17° 43° 201 93 29 2 0
03-03 27° 43° 214 96 29 2 0
03-04 30° 46° 229 101 29 2 0
03-05 37° 46° 249 111 29 2 0
03-06 40° 63° 279 131 38 4 0
03-07 39° 62° 307 149 46 4 0
03-08 32° 60° 331 163 51 4 0
03-09 47° 72° 369 191 68 14 5
03-10 38° 60° 396 208 75 14 5
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-11 32° 40° 410 212 75 14 5
03-12 29° 44° 425 217 75 14 5
03-13 33° 45° 442 224 75 14 5
03-14 25° 36° 450 224 75 14 5
03-15 30° 47° 466 230 75 14 5
03-16 17° 29° 467 230 75 14 5
03-17 5° 21° 467 230 75 14 5
03-18 18° 39° 473 230 75 14 5
03-19 30° 52° 493 239 75 14 5
03-20 35° 64° 520 257 83 14 5
03-21 37° 66° 550 277 93 15 5
03-22 31° 61° 574 290 96 15 5
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-23 29° 42° 587 294 96 15 5
03-24 28° 50° 605 301 96 15 5
03-25 36° 71° 637 323 108 19 5
03-26 34° 62° 663 339 114 19 5
03-27 29° 42° 676 343 114 19 5
03-28 22° 47° 689 345 114 19 5
03-29 38° 63° 718 364 123 20 5
03-30 45° 80° 758 395 144 32 12
03-31 41° 72° 793 420 159 39 14
04-01 33° 40° 808 424 159 39 14
04-02 33° 68° 836 442 167 39 14
04-03 38° 60° 863 459 174 39 14
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-04 38° 49° 884 471 175 39 14
04-05 35° 51° 905 482 176 39 14
04-06 31° 48° 923 489 176 39 14
04-07 25° 37° 932 489 176 39 14
04-08 31° 70° 961 508 185 40 14
04-09 48° 68° 997 534 202 49 17
04-10 37° 51° 1019 546 203 49 17
04-11 31° 54° 1039 557 204 49 17
04-12 47° 78° 1080 587 224 61 24
04-13 60° 77° 1126 624 251 79 38
04-14 56° 81° 1173 660 278 98 52
04-15 62° 71° 1217 695 302 115 63
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-16 51° 70° 1256 724 321 125 69
04-17 50° 78° 1298 756 343 140 78
04-18 39° 63° 1327 775 352 141 78
04-19 33° 48° 1346 784 352 141 78
04-20 30° 54° 1366 794 352 141 78
04-21 46° 76° 1406 823 371 152 85
04-22 50° 71° 1445 852 390 163 90
04-23 48° 82° 1488 885 413 178 100
04-24 57° 72° 1530 917 436 192 110
04-25 45° 59° 1560 937 446 194 110
04-26 40° 55° 1585 953 451 194 110
04-27 44° 66° 1618 976 464 199 110
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-28 51° 63° 1653 1001 479 206 112
04-29 41° 56° 1680 1017 486 206 112
04-30 33° 51° 1700 1028 486 206 112
05-01 35° 46° 1719 1036 486 206 112
05-02 30° 53° 1738 1046 486 206 112
05-03 43° 69° 1772 1069 500 212 113
05-04 47° 80° 1813 1101 521 225 121
05-05 47° 63° 1846 1123 534 230 121
05-06 34° 55° 1869 1136 536 230 121
05-07 31° 56° 1890 1148 538 230 121
05-08 33° 66° 1918 1165 545 230 121
05-09 52° 72° 1958 1195 565 242 128
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-10 36° 62° 1985 1212 572 242 128
05-11 39° 55° 2010 1227 578 242 128
05-12 35° 69° 2040 1248 588 244 128
05-13 43° 63° 2072 1269 599 248 128
05-14 36° 68° 2102 1289 609 250 128
05-15 51° 76° 2143 1321 631 263 136
05-16 61° 84° 2194 1362 662 286 154
05-17 60° 83° 2243 1401 691 307 170
05-18 70° 83° 2298 1445 726 334 192
05-19 60° 79° 2345 1483 753 353 206
05-20 46° 58° 2375 1503 763 355 206
05-21 42° 54° 2402 1519 769 355 206
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-22 47° 65° 2436 1543 783 361 207
05-23 54° 71° 2476 1574 804 374 215
05-24 54° 77° 2520 1607 828 390 225
05-25 56° 84° 2568 1646 856 410 240
05-26 61° 85° 2619 1687 887 433 258
05-27 58° 85° 2669 1726 916 454 275
05-28 53° 71° 2709 1756 937 466 282
05-29 46° 84° 2752 1789 960 481 292
05-30 54° 68° 2791 1819 979 493 299
05-31 49° 74° 2831 1848 999 504 305
06-01 56° 73° 2874 1881 1021 519 315
06-02 51° 74° 2914 1911 1042 531 322
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-03 47° 83° 2957 1944 1064 546 332
06-04 56° 87° 3006 1984 1094 568 348
06-05 67° 77° 3056 2023 1124 590 365
06-06 67° 83° 3109 2066 1157 615 385
06-07 62° 79° 3157 2105 1185 635 401
06-08 63° 79° 3206 2144 1214 656 417
06-09 71° 86° 3263 2190 1250 684 440
06-10 66° 92° 3320 2237 1287 713 464
06-11 70° 88° 3377 2284 1325 742 488
06-12 59° 77° 3423 2320 1350 760 501
06-13 59° 85° 3473 2360 1380 782 518
06-14 60° 77° 3519 2396 1407 801 531
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-15 54° 73° 3560 2428 1428 814 540
06-16 53° 75° 3602 2460 1450 828 549
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-15 23° 31° 5 0 0 0 0
02-16 10° 25° 5 0 0 0 0
02-17 -0° 8° 5 0 0 0 0
02-18 -9° 9° 5 0 0 0 0
02-19 -2° 12° 5 0 0 0 0
02-20 0° 24° 5 0 0 0 0
02-21 6° 24° 5 0 0 0 0
02-22 11° 29° 5 0 0 0 0
02-23 18° 39° 12 0 0 0 0
02-24 35° 53° 34 12 2 0 0
02-25 35° 53° 56 24 4 0 0
02-26 34° 45° 74 32 4 0 0
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-27 32° 45° 90 38 4 0 0
02-28 31° 57° 112 50 6 0 0
03-01 19° 33° 116 50 6 0 0
03-02 13° 34° 118 50 6 0 0
03-03 27° 48° 134 56 6 0 0
03-04 42° 50° 158 70 10 0 0
03-05 27° 50° 174 76 10 0 0
03-06 24° 39° 184 76 10 0 0
03-07 31° 36° 196 78 10 0 0
03-08 26° 49° 211 84 10 0 0
03-09 31° 58° 234 97 13 0 0
03-10 36° 67° 264 116 23 2 0
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-11 32° 59° 287 130 26 2 0
03-12 32° 52° 307 139 26 2 0
03-13 30° 58° 329 152 28 2 0
03-14 40° 78° 366 179 45 11 4
03-15 41° 68° 399 202 58 16 4
03-16 27° 39° 411 203 58 16 4
03-17 18° 53° 424 206 58 16 4
03-18 39° 64° 453 226 68 17 4
03-19 35° 43° 470 233 68 17 4
03-20 30° 42° 484 237 68 17 4
03-21 26° 57° 504 246 68 17 4
03-22 30° 49° 521 254 68 17 4
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-23 31° 52° 541 263 68 17 4
03-24 32° 47° 558 271 68 17 4
03-25 28° 48° 574 277 68 17 4
03-26 28° 51° 592 285 68 17 4
03-27 37° 57° 617 299 72 17 4
03-28 46° 77° 657 329 92 29 11
03-29 35° 69° 686 349 102 31 11
03-30 38° 58° 712 365 108 31 11
03-31 32° 45° 729 372 108 31 11
04-01 28° 42° 742 375 108 31 11
04-02 37° 65° 771 394 117 32 11
04-03 40° 59° 798 411 124 32 11
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-04 33° 47° 816 419 124 32 11
04-05 38° 52° 840 432 128 32 11
04-06 31° 49° 857 440 128 32 11
04-07 30° 41° 871 444 128 32 11
04-08 24° 41° 882 444 128 32 11
04-09 32° 43° 897 450 128 32 11
04-10 35° 39° 913 455 128 32 11
04-11 31° 52° 932 465 128 32 11
04-12 32° 61° 957 480 132 32 11
04-13 49° 62° 991 503 146 37 12
04-14 50° 63° 1025 528 161 44 14
04-15 37° 53° 1048 541 164 44 14
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-16 30° 51° 1067 549 164 44 14
04-17 36° 63° 1094 567 171 44 14
04-18 56° 73° 1137 599 194 58 23
04-19 46° 64° 1170 622 207 64 23
04-20 40° 51° 1193 636 210 64 23
04-21 46° 57° 1223 655 220 65 23
04-22 37° 73° 1256 678 233 70 23
04-23 50° 77° 1297 709 254 83 32
04-24 51° 70° 1335 737 272 93 37
04-25 47° 59° 1366 759 283 96 37
04-26 43° 56° 1393 776 290 96 37
04-27 36° 69° 1424 797 301 99 37
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-28 50° 85° 1470 832 327 117 49
04-29 50° 79° 1512 865 349 131 59
04-30 39° 59° 1540 882 357 131 59
05-01 46° 59° 1570 903 367 134 59
05-02 45° 55° 1598 921 375 134 59
05-03 42° 53° 1624 936 381 134 59
05-04 41° 60° 1653 955 390 134 59
05-05 47° 55° 1682 974 399 135 59
05-06 44° 76° 1720 1003 417 146 64
05-07 50° 66° 1756 1028 433 154 67
05-08 43° 57° 1784 1047 441 154 67
05-09 35° 68° 1814 1066 451 156 67
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-10 47° 67° 1849 1092 466 163 69
05-11 38° 71° 1882 1114 479 167 69
05-12 46° 81° 1923 1145 500 181 77
05-13 60° 76° 1969 1181 526 199 90
05-14 58° 79° 2015 1218 552 217 104
05-15 57° 93° 2069 1261 586 242 124
05-16 60° 86° 2119 1302 616 265 142
05-17 53° 67° 2158 1330 635 276 147
05-18 43° 60° 2187 1350 644 277 147
05-19 40° 50° 2210 1363 647 277 147
05-20 44° 50° 2235 1378 652 277 147
05-21 45° 49° 2260 1393 657 277 147
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-22 46° 55° 2289 1412 666 278 147
05-23 40° 61° 2318 1430 675 278 147
05-24 41° 64° 2348 1451 685 281 147
05-25 49° 67° 2384 1477 701 289 150
05-26 43° 67° 2417 1500 714 294 150
05-27 51° 69° 2455 1528 732 304 155
05-28 55° 60° 2491 1553 748 311 158
05-29 51° 71° 2530 1582 767 322 164
05-30 51° 73° 2570 1612 787 334 171
05-31 48° 64° 2604 1636 801 341 172
06-01 41° 69° 2637 1659 814 346 172
06-02 47° 85° 2681 1693 838 361 183
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-03 67° 85° 2735 1737 872 388 204
06-04 58° 71° 2777 1770 894 402 214
06-05 53° 75° 2819 1802 916 416 222
06-06 57° 76° 2864 1836 941 433 234
06-07 53° 77° 2907 1869 964 448 244
06-08 57° 80° 2953 1906 990 466 257
06-09 54° 67° 2992 1934 1009 477 263
06-10 53° 77° 3035 1968 1032 492 273
06-11 60° 92° 3089 2012 1066 518 294
06-12 62° 75° 3135 2048 1092 536 307
06-13 57° 72° 3178 2080 1115 551 317
06-14 56° 74° 3221 2114 1138 566 327
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-15 56° 80° 3267 2150 1164 584 340
06-16 61° 86° 3318 2191 1195 607 358
06-17 69° 94° 3377 2240 1234 638 385
06-18 67° 79° 3428 2281 1265 661 403
06-19 65° 86° 3482 2324 1299 686 423
06-20 68° 85° 3536 2369 1333 713 444
06-21 76° 93° 3599 2421 1376 748 474
06-22 78° 94° 3663 2475 1420 784 505
06-23 78° 93° 3726 2529 1463 819 536
06-24 73° 87° 3785 2577 1502 849 561
06-25 67° 84° 3838 2621 1535 875 581
06-26 71° 90° 3897 2669 1574 906 607
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-27 73° 85° 3954 2717 1611 935 631
06-28 63° 85° 4006 2759 1643 959 650
06-29 68° 91° 4064 2806 1681 988 675
06-30 71° 86° 4120 2853 1717 1017 698
07-01 67° 84° 4173 2896 1750 1042 719
07-02 67° 88° 4228 2941 1785 1069 741
07-03 67° 90° 4285 2988 1822 1098 764
07-04 71° 89° 4343 3036 1860 1128 789
07-05 72° 90° 4403 3085 1900 1160 816
07-06 65° 82° 4454 3127 1931 1183 834
07-07 61° 79° 4502 3165 1959 1203 849
07-08 63° 79° 4551 3203 1988 1224 865
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-09 67° 80° 4602 3245 2019 1247 883
07-10 61° 81° 4651 3283 2048 1268 899
07-11 68° 84° 4705 3327 2082 1294 920
07-12 68° 83° 4758 3371 2115 1319 941
07-13 64° 78° 4807 3410 2144 1340 957
07-14 62° 85° 4859 3451 2176 1363 975
07-15 65° 87° 4913 3495 2210 1390 996
07-16 72° 89° 4971 3544 2248 1420 1021
07-17 58° 69° 5013 3576 2270 1434 1030
07-18 55° 77° 5057 3609 2294 1450 1041
07-19 65° 82° 5109 3651 2326 1473 1060
07-20 63° 74° 5155 3688 2352 1492 1073
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-21 58° 78° 5201 3723 2378 1509 1086
07-22 62° 84° 5252 3764 2409 1533 1104
07-23 69° 92° 5311 3813 2448 1563 1130
07-24 78° 88° 5372 3864 2489 1597 1158
07-25 71° 81° 5426 3908 2523 1622 1179
07-26 69° 83° 5480 3953 2557 1649 1200
07-27 70° 88° 5537 3999 2594 1678 1224
07-28 73° 92° 5597 4050 2634 1710 1252
07-29 71° 90° 5656 4099 2673 1741 1277
07-30 65° 77° 5705 4138 2702 1762 1293
07-31 63° 74° 5751 4174 2728 1780 1307
08-01 59° 73° 5796 4208 2753 1796 1318
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-02 54° 78° 5839 4242 2776 1812 1328
08-03 55° 78° 5884 4277 2801 1829 1340
08-04 59° 78° 5931 4313 2828 1847 1354
08-05 60° 81° 5979 4352 2856 1868 1369
08-06 60° 85° 6030 4392 2887 1891 1387
08-07 66° 88° 6085 4438 2922 1918 1409
08-08 72° 91° 6145 4487 2962 1949 1436
08-09 74° 92° 6206 4538 3003 1982 1464
08-10 71° 83° 6261 4583 3038 2009 1486
08-11 74° 85° 6318 4630 3075 2039 1510
08-12 70° 82° 6372 4674 3109 2064 1531
08-13 66° 82° 6423 4716 3140 2088 1549
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-14 62° 82° 6473 4756 3170 2110 1566
08-15 65° 88° 6528 4800 3205 2136 1588
08-16 72° 90° 6587 4849 3244 2167 1614
08-17 68° 77° 6637 4890 3274 2190 1631
08-18 67° 81° 6689 4932 3306 2214 1650
08-19 68° 76° 6739 4972 3336 2236 1668
08-20 64° 74° 6786 5009 3363 2255 1682
08-21 61° 75° 6832 5045 3389 2273 1695
08-22 59° 80° 6880 5083 3417 2293 1709
08-23 62° 80° 6929 5121 3446 2314 1725
08-24 55° 70° 6969 5152 3466 2326 1733
08-25 51° 67° 7007 5179 3484 2335 1737
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-26 49° 71° 7044 5207 3501 2345 1742
08-27 51° 74° 7085 5237 3522 2357 1749
08-28 59° 73° 7129 5271 3546 2374 1760
08-29 50° 69° 7166 5299 3563 2383 1764
08-30 56° 71° 7208 5330 3585 2396 1773
08-31 47° 74° 7246 5358 3603 2407 1778
09-01 51° 76° 7288 5390 3625 2420 1787
09-02 52° 77° 7330 5423 3647 2435 1796
09-03 55° 69° 7370 5452 3667 2446 1803
09-04 44° 64° 7402 5474 3679 2450 1803
09-05 51° 63° 7437 5499 3694 2458 1805
09-06 45° 64° 7470 5522 3707 2462 1805
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
09-07 43° 65° 7502 5544 3719 2467 1805
09-08 43° 71° 7537 5570 3734 2474 1807
09-09 49° 75° 7577 5599 3754 2486 1814
09-10 53° 77° 7620 5633 3777 2501 1824
09-11 56° 75° 7664 5667 3801 2517 1835
09-12 59° 82° 7713 5705 3830 2538 1851
09-13 62° 79° 7762 5744 3859 2558 1867
09-14 62° 81° 7812 5784 3889 2580 1884
09-15 58° 81° 7859 5822 3916 2600 1898
09-16 57° 83° 7907 5860 3944 2620 1913
09-17 56° 83° 7955 5897 3972 2639 1928
09-18 59° 85° 8005 5937 4002 2661 1945
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
09-19 62° 85° 8056 5979 4033 2685 1963
09-20 64° 77° 8105 6018 4062 2706 1979
09-21 64° 79° 8155 6057 4092 2727 1996
09-22 61° 78° 8202 6095 4119 2747 2010
09-23 62° 72° 8247 6130 4144 2764 2022
09-24 58° 69° 8289 6162 4166 2778 2031
09-25 56° 72° 8331 6194 4188 2792 2040
09-26 54° 82° 8377 6230 4214 2810 2053
09-27 59° 84° 8427 6269 4244 2832 2070
09-28 57° 77° 8472 6304 4269 2849 2082
09-29 54° 86° 8520 6342 4297 2869 2097
09-30 58° 81° 8567 6380 4324 2888 2111
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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