| Tahun Data | : | 1998 |
| Nama Stasiun | : | PANGKALAN KASAI |
| Lokasi Stasiun | : | Desa Kelurahan Pangkalan Kasai, Kecamatan Siberida, Indragiri Hulu, Provinsi Riau |
| Longitude | : | 102.390280 |
| Latitude | : | -0.591390 |
| Pengelola | : | BWS SUMATERA III |
| Tanggal | Jan | Feb | Mar | Apr | Mei | Jun | Jul | Agu | Sep | Okt | Nov | Des |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 5.50 | 40.80 | 0.00 | 22.30 | 0.00 | 2.70 | 0.00 | 0.00 | 0.00 | 0.00 | 66.70 | 6.80 |
| 2 | 2.90 | 35.50 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 46.60 | 0.00 | 0.00 | 0.00 | 0.00 |
| 3 | 26.60 | 0.00 | 0.00 | 5.10 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
| 4 | 19.50 | 0.00 | 0.00 | 9.00 | 26.30 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 17.70 | 48.80 |
| 5 | 27.00 | 0.00 | 0.00 | 17.40 | 19.90 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
| 6 | 0.00 | 0.00 | 18.30 | 0.00 | 0.00 | 104.80 | 0.00 | 18.30 | 40.90 | 0.00 | 0.00 | 60.30 |
| 7 | 0.00 | 0.00 | 48.90 | 0.00 | 0.00 | 50.70 | 0.00 | 26.90 | 0.00 | 0.00 | 0.00 | 21.50 |
| 8 | 18.20 | 0.00 | 0.00 | 0.00 | 9.90 | 0.00 | 0.00 | 0.00 | 28.30 | 0.00 | 0.00 | 0.00 |
| 9 | 4.40 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 18.90 | 11.60 | 56.60 | 0.00 | 0.00 | 0.00 |
| 10 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 9.30 | 39.80 | 0.00 | 0.00 | 0.00 |
| 11 | 0.00 | 0.00 | 59.70 | 28.10 | 0.00 | 0.00 | 0.00 | 15.80 | 0.00 | 0.00 | 0.00 | 2.90 |
| 12 | 0.00 | 0.00 | 0.00 | 0.00 | 24.60 | 0.00 | 61.90 | 10.10 | 0.00 | 0.00 | 0.00 | 0.00 |
| 13 | 0.00 | 0.00 | 0.00 | 0.00 | 89.00 | 30.70 | 0.00 | 6.80 | 0.00 | 0.00 | 0.00 | 0.00 |
| 14 | 0.00 | 0.00 | 0.00 | 7.70 | 0.00 | 0.00 | 0.00 | 46.60 | 11.20 | 0.00 | 0.00 | 0.00 |
| 15 | 0.00 | 0.00 | 2.90 | 0.00 | 0.00 | 0.00 | 0.00 | 15.60 | 17.10 | 0.00 | 0.00 | 0.00 |
| 16 | 0.00 | 29.60 | 0.00 | 0.00 | 3.10 | 0.00 | 0.00 | 27.30 | 0.00 | 0.00 | 0.00 | 0.00 |
| 17 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 18.50 | 0.00 | 0.00 | 0.00 |
| 18 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 53.30 | 24.60 | 40.80 | 0.00 | 0.00 | 0.00 |
| 19 | 0.00 | 0.00 | 19.10 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 8.30 | 0.00 | 0.00 | 18.30 |
| 20 | 0.00 | 0.00 | 13.90 | 2.90 | 0.00 | 0.00 | 0.00 | 0.00 | 19.60 | 0.00 | 0.00 | 40.80 |
| 21 | 0.00 | 0.00 | 0.00 | 3.60 | 0.00 | 0.00 | 0.00 | 12.10 | 0.00 | 0.00 | 0.00 | 19.60 |
| 22 | 0.00 | 27.20 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 19.50 | 0.00 | 49.80 | 0.00 | 39.70 |
| 23 | 0.00 | 12.40 | 0.00 | 52.50 | 0.00 | 0.00 | 11.90 | 0.00 | 0.00 | 0.00 | 0.00 | 13.20 |
| 24 | 0.00 | 0.00 | 20.00 | 0.00 | 0.00 | 0.00 | 0.00 | 38.80 | 18.20 | 0.00 | 0.00 | 0.00 |
| 25 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 14.60 | 69.30 | 0.00 | 72.80 | 0.00 | 12.90 |
| 26 | 0.00 | 0.00 | 0.00 | 36.60 | 17.30 | 0.00 | 0.00 | 16.90 | 0.00 | 0.00 | 0.00 | 60.30 |
| 27 | 0.00 | 0.00 | 5.60 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 11.30 |
| 28 | 18.60 | 0.00 | 17.40 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 6.80 | 0.00 | 21.50 |
| 29 | 0.00 | - | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 5.90 | 0.00 | 0.00 | 5.70 | 56.60 |
| 30 | 0.00 | - | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
| 31 | 0.00 | - | 18.90 | - | 0.00 | - | 0.00 | 0.00 | - | 0.00 | - | 29.20 |
| Total | 122.70 | 145.50 | 224.70 | 185.20 | 190.10 | 188.90 | 160.60 | 422.00 | 299.30 | 129.40 | 90.10 | 463.70 |
| Hari Hujan | 8.00 | 5.00 | 10.00 | 10.00 | 7.00 | 4.00 | 5.00 | 18.00 | 11.00 | 3.00 | 3.00 | 16.00 |
| Max | 27.00 | 40.80 | 59.70 | 52.50 | 89.00 | 104.80 | 61.90 | 69.30 | 56.60 | 72.80 | 66.70 | 60.30 |
| Avg | 3.96 | 5.20 | 7.25 | 6.17 | 6.13 | 6.30 | 5.18 | 13.61 | 9.98 | 4.17 | 3.00 | 14.96 |
Berdasarkan data tercatat di Stasiun PANGKALAN KASAI, yang terletak di Desa Kelurahan Pangkalan Kasai, Kecamatan Siberida, Indragiri Hulu, Provinsi Riau, curah hujan tahunan yang terjadi pada tahun 1998 adalah sebesar 2,622.20 mm. Dengan jumlah hari hujan tahunan adalah 100 hari (27.40%). Curah hujan harian maksimum tahunan yang tercatat adalah sebesar 104.80 mm yang terjadi pada tanggal 6 Juni 1998.