| Tahun Data | : | 1999 |
| Nama Stasiun | : | TRMM-0258 |
| Lokasi Stasiun | : | Desa Wek Iii, Kecamatan Batang Toru, Tapanuli Selatan, Provinsi Sumatera Utara |
| Longitude | : | 99.125000 |
| Latitude | : | 1.625000 |
| Tanggal | Jan | Feb | Mar | Apr | Mei | Jun | Jul | Agu | Sep | Okt | Nov | Des |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 22.510 | 0.000 | 0.000 | 0.000 | 0.616 | 0.000 | 0.000 | 0.000 | 0.994 | 9.784 | 0.000 | 6.157 |
| 2 | 16.819 | 6.343 | 13.478 | 44.823 | 0.000 | 0.000 | 17.688 | 0.000 | 20.103 | 7.806 | 1.480 | 10.669 |
| 3 | 2.236 | 42.863 | 10.709 | 0.000 | 25.720 | 0.000 | 0.308 | 10.728 | 9.278 | 0.000 | 0.000 | 74.254 |
| 4 | 13.466 | 0.000 | 0.000 | 4.926 | 0.550 | 0.000 | 2.820 | 16.300 | 40.648 | 44.964 | 0.000 | 9.328 |
| 5 | 0.000 | 25.333 | 19.486 | 6.143 | 0.000 | 0.000 | 4.666 | 1.296 | 0.000 | 0.624 | 0.000 | 109.796 |
| 6 | 0.000 | 5.036 | 0.000 | 7.359 | 0.638 | 0.000 | 17.791 | 30.501 | 0.000 | 12.490 | 3.854 | 0.000 |
| 7 | 0.000 | 24.334 | 0.000 | 18.915 | 9.782 | 0.000 | 0.000 | 16.533 | 1.132 | 9.576 | 1.824 | 5.426 |
| 8 | 6.402 | 22.642 | 10.814 | 0.000 | 2.132 | 27.967 | 2.358 | 0.000 | 7.180 | 5.360 | 0.000 | 14.509 |
| 9 | 11.026 | 25.449 | 8.411 | 3.406 | 9.673 | 10.974 | 7.280 | 0.985 | 0.690 | 0.052 | 0.172 | 0.000 |
| 10 | 0.000 | 7.765 | 11.702 | 0.000 | 3.012 | 9.561 | 24.200 | 4.405 | 19.219 | 34.659 | 10.082 | 0.000 |
| 11 | 23.476 | 0.000 | 9.247 | 0.000 | 2.000 | 20.558 | 1.589 | 18.684 | 2.706 | 8.275 | 10.116 | 0.000 |
| 12 | 0.965 | 4.728 | 24.553 | 0.000 | 1.429 | 0.000 | 0.000 | 8.733 | 0.000 | 17.746 | 19.441 | 6.462 |
| 13 | 4.065 | 26.102 | 6.791 | 0.000 | 0.000 | 7.524 | 25.584 | 8.292 | 13.365 | 19.359 | 10.907 | 0.000 |
| 14 | 3.252 | 10.918 | 11.702 | 0.061 | 2.880 | 17.016 | 9.126 | 0.000 | 20.158 | 49.127 | 3.475 | 0.000 |
| 15 | 17.327 | 33.291 | 0.522 | 0.000 | 10.750 | 0.509 | 0.000 | 11.869 | 0.000 | 31.069 | 4.473 | 0.000 |
| 16 | 0.000 | 3.383 | 8.463 | 0.000 | 8.134 | 18.104 | 0.000 | 3.913 | 24.079 | 7.494 | 8.568 | 2.500 |
| 17 | 6.301 | 5.382 | 9.874 | 44.641 | 0.000 | 0.000 | 12.971 | 0.000 | 7.483 | 0.000 | 1.480 | 56.575 |
| 18 | 2.185 | 13.109 | 0.000 | 0.000 | 10.684 | 11.877 | 0.000 | 0.726 | 3.424 | 1.717 | 4.335 | 8.901 |
| 19 | 19.004 | 0.923 | 0.000 | 0.851 | 5.210 | 0.000 | 0.000 | 15.548 | 24.300 | 22.013 | 23.225 | 0.000 |
| 20 | 6.809 | 26.218 | 1.828 | 7.298 | 1.781 | 0.000 | 0.000 | 3.239 | 28.028 | 10.773 | 19.578 | 17.131 |
| 21 | 0.000 | 3.575 | 10.135 | 0.851 | 0.374 | 0.000 | 0.000 | 18.425 | 8.698 | 0.000 | 4.507 | 0.000 |
| 22 | 1.728 | 0.154 | 2.455 | 0.487 | 5.540 | 18.914 | 0.000 | 1.011 | 0.000 | 9.784 | 0.000 | 0.000 |
| 23 | 9.858 | 13.916 | 8.411 | 0.000 | 6.991 | 0.000 | 0.000 | 22.390 | 14.359 | 38.875 | 0.000 | 16.582 |
| 24 | 24.594 | 0.000 | 0.000 | 0.000 | 48.759 | 9.886 | 0.000 | 16.766 | 18.142 | 14.155 | 7.157 | 9.328 |
| 25 | 2.287 | 76.500 | 0.000 | 0.000 | 0.616 | 1.273 | 0.000 | 67.609 | 6.572 | 0.000 | 9.187 | 0.000 |
| 26 | 1.728 | 0.000 | 9.142 | 7.663 | 0.000 | 0.000 | 0.000 | 0.000 | 7.815 | 9.524 | 31.518 | 0.610 |
| 27 | 0.000 | 2.653 | 21.262 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 43.657 | 13.271 | 24.327 | 0.000 |
| 28 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 1.435 | 0.000 | 23.711 | 2.292 | 31.589 | 22.778 | 0.000 |
| 29 | 0.000 | - | 2.351 | 0.000 | 0.000 | 5.371 | 1.589 | 2.332 | 39.598 | 10.981 | 2.202 | 0.000 |
| 30 | 0.000 | - | 2.037 | 0.487 | 0.000 | 0.000 | 0.000 | 0.000 | 4.722 | 12.230 | 59.594 | 0.000 |
| 31 | 0.000 | - | 17.031 | - | 0.000 | - | 0.000 | 3.498 | - | 0.781 | - | 3.109 |
| Total | 196.04 | 380.62 | 220.40 | 147.91 | 157.27 | 160.97 | 127.97 | 307.49 | 368.64 | 434.08 | 284.28 | 351.34 |
| Hari Hujan | 20.00 | 22.00 | 22.00 | 14.00 | 21.00 | 14.00 | 13.00 | 23.00 | 25.00 | 27.00 | 23.00 | 16.00 |
| Max | 24.594 | 76.500 | 24.553 | 44.823 | 48.759 | 27.967 | 25.584 | 67.609 | 43.657 | 49.127 | 59.594 | 109.796 |
| Avg | 6.32 | 13.59 | 7.11 | 4.93 | 5.07 | 5.37 | 4.13 | 9.92 | 12.29 | 14.00 | 9.48 | 11.33 |
Berdasarkan data hujan TRMM di Grid TRMM-0258, yang terletak di Desa Wek Iii, Kecamatan Batang Toru, Tapanuli Selatan, Provinsi Sumatera Utara, curah hujan tahunan yang terjadi pada tahun 1999 adalah sebesar 3,137.01 mm. Dengan jumlah hari hujan tahunan adalah 240 hari (65.75%). Curah hujan harian maksimum tahunan yang tercatat adalah sebesar 109.80 mm yang terjadi pada tanggal 5 Desember 1999.
