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Early Season Fungicide App for Dollar Spot Suppression (GDD 50)
forecast for Mon, Apr. 6. 2026

 

Forecasted GDD Total: 78 (Base 50) through Mon, Apr. 6, 2026

  

Chicago, IL

        

Forecast »

“Flashback” to 2025

3/27

3/28

3/29

3/30

3/31

4/1

4/2

4/3

4/4

4/5

4/6

4/7

4/8

Done

201

Late

177

Target

140

Early

101

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 31° 61° 24 14 4 0 0
02-16 34° 65° 52 32 12 0 0
02-17 42° 57° 79 49 19 0 0
02-18 47° 63° 112 72 32 5 0
02-19 39° 57° 138 88 38 5 0
02-20 26° 46° 152 92 38 5 0
02-21 25° 30° 158 92 38 5 0
02-22 20° 26° 159 92 38 5 0
02-23 19° 29° 161 92 38 5 0
02-24 20° 38° 168 92 38 5 0
02-25 27° 38° 178 93 38 5 0
02-26 22° 42° 189 93 38 5 0
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-27 30° 64° 213 108 42 5 0
02-28 28° 48° 230 114 42 5 0
03-01 25° 31° 236 114 42 5 0
03-02 25° 42° 248 115 42 5 0
03-03 34° 42° 263 121 42 5 0
03-04 34° 43° 280 128 42 5 0
03-05 39° 49° 302 140 45 5 0
03-06 42° 69° 335 163 58 10 0
03-07 40° 63° 365 182 67 12 0
03-08 34° 63° 391 199 74 12 0
03-09 47° 72° 429 226 91 22 5
03-10 37° 61° 455 243 98 22 5
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-11 34° 47° 474 252 98 22 5
03-12 29° 45° 489 257 98 22 5
03-13 36° 46° 508 266 98 22 5
03-14 30° 36° 519 267 98 22 5
03-15 34° 62° 545 283 104 22 5
03-16 21° 33° 550 283 104 22 5
03-17 15° 24° 550 283 104 22 5
03-18 24° 47° 563 286 104 22 5
03-19 34° 59° 588 301 109 22 5
03-20 41° 72° 623 326 124 28 7
03-21 41° 70° 656 349 137 33 7
03-22 33° 69° 685 368 146 34 7
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-23 31° 40° 699 372 146 34 7
03-24 29° 52° 717 380 146 34 7
03-25 40° 71° 751 404 160 40 8
03-26 35° 71° 782 425 171 43 8
03-27 32° 42° 796 429 171 43 8
03-28 28° 48° 812 435 171 43 8
03-29 40° 63° 842 455 180 45 8
03-30 50° 81° 885 488 204 60 18
03-31 41° 70° 918 511 217 65 18
04-01 37° 40° 935 518 217 65 18
04-02 38° 69° 967 540 229 69 18
04-03 50° 61° 1000 563 242 74 18
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-04 45° 62° 1032 584 254 78 18
04-05 37° 51° 1054 596 256 78 18
04-06 38° 52° 1077 610 259 78 18
04-07 31° 43° 1092 615 259 78 18
04-08 33° 60° 1116 629 263 78 18
04-09 49° 65° 1151 654 278 85 20
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-15 24° 34° 7 0 0 0 0
02-16 13° 30° 7 0 0 0 0
02-17 2° 11° 7 0 0 0 0
02-18 -5° 15° 7 0 0 0 0
02-19 5° 18° 7 0 0 0 0
02-20 4° 25° 7 0 0 0 0
02-21 10° 29° 7 0 0 0 0
02-22 15° 36° 11 0 0 0 0
02-23 24° 45° 24 3 0 0 0
02-24 38° 54° 48 17 4 0 0
02-25 37° 54° 71 31 8 0 0
02-26 35° 49° 91 41 8 0 0
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-27 35° 49° 111 51 8 0 0
02-28 33° 57° 134 63 11 0 0
03-01 22° 38° 142 63 11 0 0
03-02 17° 37° 147 63 11 0 0
03-03 29° 47° 163 69 11 0 0
03-04 43° 46° 186 82 14 0 0
03-05 30° 49° 203 89 14 0 0
03-06 27° 40° 215 91 14 0 0
03-07 32° 38° 228 94 14 0 0
03-08 30° 49° 246 102 14 0 0
03-09 32° 58° 269 115 17 0 0
03-10 39° 68° 300 136 28 3 0
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-11 36° 58° 325 151 33 3 0
03-12 35° 50° 346 162 33 3 0
03-13 33° 58° 369 175 37 3 0
03-14 43° 77° 407 204 55 14 6
03-15 46° 69° 443 229 70 21 8
03-16 30° 44° 458 234 70 21 8
03-17 26° 53° 475 241 70 21 8
03-18 45° 73° 512 268 87 30 12
03-19 39° 53° 536 282 91 30 12
03-20 31° 43° 550 287 91 30 12
03-21 30° 58° 573 299 93 30 12
03-22 34° 52° 594 310 94 30 12
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-23 34° 48° 612 319 94 30 12
03-24 34° 49° 632 328 94 30 12
03-25 30° 49° 649 335 94 30 12
03-26 30° 51° 668 344 94 30 12
03-27 40° 54° 693 359 99 30 12
03-28 47° 78° 734 390 120 43 19
03-29 53° 69° 773 419 139 54 26
03-30 46° 76° 812 448 158 65 32
03-31 35° 45° 830 456 158 65 32
04-01 31° 45° 846 462 158 65 32
04-02 40° 68° 878 484 170 69 32
04-03 43° 62° 909 505 181 72 32
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-04 38° 47° 930 516 182 72 32
04-05 41° 51° 954 530 186 72 32
04-06 35° 45° 972 538 186 72 32
04-07 31° 44° 987 543 186 72 32
04-08 28° 42° 1000 546 186 72 32
04-09 33° 41° 1015 551 186 72 32
04-10 38° 43° 1034 560 186 72 32
04-11 35° 50° 1055 571 186 72 32
04-12 34° 60° 1079 585 191 72 32
04-13 51° 63° 1114 610 206 79 34
04-14 53° 63° 1151 637 222 87 37
04-15 39° 54° 1175 651 227 87 37
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-16 34° 48° 1194 660 227 87 37
04-17 38° 64° 1223 679 236 88 37
04-18 57° 76° 1267 713 260 104 48
04-19 42° 68° 1300 736 273 109 48
04-20 46° 60° 1331 757 284 112 48
04-21 49° 60° 1363 779 296 116 48
04-22 40° 73° 1398 804 311 123 50
04-23 54° 77° 1441 837 334 138 60
04-24 50° 74° 1482 868 354 150 68
04-25 47° 56° 1511 887 364 152 68
04-26 42° 51° 1535 902 368 152 68
04-27 36° 68° 1565 921 378 154 68
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-28 51° 83° 1611 957 404 171 80
04-29 51° 76° 1652 988 425 185 89
04-30 45° 60° 1682 1009 435 187 89
05-01 52° 68° 1721 1037 453 197 94
05-02 45° 59° 1750 1057 463 199 94
05-03 44° 52° 1776 1072 469 199 94
05-04 45° 55° 1804 1090 477 199 94
05-05 47° 59° 1835 1112 488 202 94
05-06 45° 76° 1874 1140 507 213 99
05-07 48° 71° 1911 1168 524 222 104
05-08 45° 56° 1940 1186 533 223 104
05-09 38° 63° 1968 1204 541 223 104
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-10 45° 73° 2005 1231 558 232 108
05-11 42° 68° 2039 1255 572 237 108
05-12 49° 74° 2078 1284 591 249 115
05-13 60° 75° 2124 1320 617 267 127
05-14 56° 76° 2168 1354 640 282 138
05-15 59° 93° 2221 1397 674 308 159
05-16 61° 86° 2273 1439 706 332 178
05-17 54° 70° 2313 1469 726 344 184
05-18 47° 61° 2345 1491 738 347 184
05-19 44° 52° 2371 1507 744 347 184
05-20 49° 55° 2401 1527 754 350 184
05-21 49° 53° 2431 1547 763 351 184
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-22 47° 54° 2459 1565 772 352 184
05-23 41° 60° 2488 1584 781 352 184
05-24 43° 63° 2519 1605 791 355 184
05-25 51° 64° 2554 1630 807 362 186
05-26 45° 65° 2586 1652 819 367 186
05-27 52° 66° 2623 1679 836 375 190
05-28 55° 61° 2659 1705 852 383 193
05-29 52° 70° 2698 1734 871 394 199
05-30 52° 74° 2739 1765 891 407 207
05-31 50° 63° 2773 1789 906 414 209
06-01 43° 65° 2805 1811 918 418 209
06-02 46° 84° 2848 1844 941 433 218
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-03 67° 87° 2903 1889 976 459 240
06-04 57° 74° 2947 1923 1000 475 251
06-05 54° 68° 2985 1952 1018 486 257
06-06 59° 76° 3031 1987 1044 504 269
06-07 55° 76° 3075 2021 1067 519 280
06-08 58° 80° 3122 2058 1095 538 294
06-09 55° 72° 3163 2089 1116 552 303
06-10 55° 78° 3207 2124 1140 568 314
06-11 63° 91° 3263 2169 1176 595 336
06-12 63° 79° 3312 2208 1205 616 352
06-13 61° 70° 3355 2241 1228 632 363
06-14 61° 72° 3400 2276 1253 649 375
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-15 57° 78° 3446 2312 1279 666 387
06-16 60° 85° 3497 2353 1309 689 405
06-17 71° 90° 3555 2401 1348 720 430
06-18 67° 81° 3607 2443 1380 744 449
06-19 65° 81° 3658 2484 1411 767 468
06-20 67° 83° 3711 2527 1444 792 488
06-21 75° 93° 3774 2580 1486 826 517
06-22 78° 94° 3837 2633 1530 862 548
06-23 77° 94° 3901 2687 1574 897 578
06-24 75° 92° 3963 2739 1616 931 607
06-25 70° 83° 4018 2784 1651 958 629
06-26 75° 92° 4079 2835 1692 991 657
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-27 76° 87° 4138 2885 1731 1023 684
06-28 68° 84° 4192 2928 1765 1049 705
06-29 71° 89° 4250 2976 1803 1079 730
06-30 73° 88° 4309 3025 1842 1110 755
07-01 70° 85° 4365 3071 1878 1137 778
07-02 69° 88° 4421 3117 1914 1165 801
07-03 70° 90° 4479 3165 1952 1196 826
07-04 74° 90° 4539 3215 1992 1228 853
07-05 73° 92° 4600 3266 2033 1260 881
07-06 69° 85° 4655 3311 2068 1287 903
07-07 65° 81° 4706 3352 2099 1310 921
07-08 66° 86° 4760 3396 2133 1337 942
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-09 69° 82° 4814 3440 2167 1362 963
07-10 66° 82° 4865 3482 2198 1386 982
07-11 70° 88° 4922 3528 2235 1415 1006
07-12 71° 81° 4976 3572 2269 1441 1026
07-13 67° 81° 5028 3615 2301 1465 1046
07-14 62° 86° 5080 3657 2333 1489 1065
07-15 68° 90° 5137 3704 2370 1518 1089
07-16 73° 89° 5196 3752 2409 1549 1115
07-17 64° 75° 5244 3790 2437 1569 1130
07-18 59° 80° 5292 3828 2464 1588 1144
07-19 72° 82° 5347 3873 2499 1615 1166
07-20 68° 75° 5396 3912 2529 1636 1182
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-21 64° 82° 5447 3953 2560 1660 1200
07-22 67° 86° 5501 3997 2594 1686 1221
07-23 71° 93° 5561 4047 2634 1717 1248
07-24 72° 94° 5621 4097 2674 1750 1276
07-25 74° 81° 5677 4143 2710 1777 1298
07-26 72° 82° 5732 4188 2745 1805 1321
07-27 73° 86° 5790 4236 2783 1834 1345
07-28 76° 89° 5851 4287 2823 1867 1373
07-29 70° 91° 5909 4335 2862 1898 1398
07-30 70° 80° 5962 4378 2895 1923 1419
07-31 67° 74° 6011 4417 2924 1943 1434
08-01 62° 75° 6057 4453 2950 1962 1447
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-02 58° 78° 6103 4489 2976 1980 1460
08-03 59° 78° 6150 4526 3003 1998 1474
08-04 63° 80° 6199 4565 3032 2020 1490
08-05 63° 82° 6249 4606 3062 2042 1508
08-06 65° 86° 6303 4649 3096 2067 1528
08-07 71° 88° 6360 4696 3133 2097 1552
08-08 72° 90° 6419 4746 3172 2128 1579
08-09 73° 92° 6480 4796 3213 2160 1606
08-10 76° 89° 6540 4846 3253 2193 1633
08-11 74° 88° 6599 4895 3292 2224 1660
08-12 73° 85° 6656 4942 3329 2253 1684
08-13 69° 82° 6710 4986 3363 2278 1704
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-14 65° 81° 6761 5027 3394 2301 1722
08-15 66° 90° 6817 5073 3430 2329 1745
08-16 74° 94° 6879 5125 3472 2363 1774
08-17 70° 80° 6932 5168 3505 2389 1794
08-18 71° 83° 6987 5213 3540 2416 1817
08-19 71° 76° 7039 5255 3572 2439 1835
08-20 68° 74° 7088 5294 3601 2460 1851
08-21 63° 74° 7134 5330 3627 2479 1864
08-22 64° 78° 7183 5369 3656 2500 1880
08-23 66° 82° 7235 5411 3688 2523 1899
08-24 57° 72° 7277 5444 3710 2538 1909
08-25 54° 69° 7317 5473 3730 2549 1915
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-26 52° 72° 7357 5503 3750 2561 1922
08-27 52° 76° 7399 5535 3772 2575 1931
08-28 61° 74° 7444 5571 3797 2593 1944
08-29 55° 68° 7484 5600 3817 2604 1950
08-30 61° 72° 7529 5635 3841 2621 1962
08-31 53° 75° 7571 5667 3864 2635 1971
09-01 57° 76° 7615 5701 3888 2652 1982
09-02 57° 78° 7661 5737 3914 2669 1995
09-03 59° 72° 7704 5770 3937 2685 2006
09-04 49° 66° 7740 5796 3953 2692 2008
09-05 56° 67° 7779 5825 3972 2704 2014
09-06 47° 66° 7814 5850 3987 2710 2016
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
09-07 45° 68° 7848 5874 4001 2717 2017
09-08 47° 72° 7885 5901 4018 2726 2022
09-09 48° 75° 7925 5931 4038 2738 2029
09-10 58° 81° 7973 5969 4066 2757 2043
09-11 63° 78° 8021 6007 4094 2778 2059
09-12 60° 83° 8070 6047 4123 2799 2075
09-13 63° 77° 8118 6084 4151 2819 2090
09-14 64° 81° 8168 6124 4181 2841 2107
09-15 61° 82° 8218 6164 4211 2862 2123
09-16 60° 81° 8266 6202 4239 2883 2139
09-17 59° 81° 8314 6240 4267 2903 2154
09-18 59° 85° 8365 6281 4297 2925 2171
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
09-19 64° 88° 8419 6325 4332 2951 2192
09-20 66° 78° 8468 6365 4361 2973 2209
09-21 66° 80° 8520 6406 4393 2996 2227
09-22 66° 80° 8571 6447 4424 3019 2245
09-23 65° 75° 8619 6485 4452 3040 2260
09-24 62° 71° 8664 6520 4477 3056 2272
09-25 60° 73° 8708 6555 4501 3073 2284
09-26 55° 83° 8755 6591 4528 3092 2298
09-27 60° 86° 8806 6632 4559 3115 2316
09-28 60° 78° 8853 6669 4586 3134 2330
09-29 59° 87° 8904 6710 4617 3157 2348
09-30 61° 81° 8953 6749 4646 3177 2363
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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