Karnataka spans three dramatically different rainfall zones — the extremely wet Western Ghats coast, the moderate Deccan plateau (Bengaluru), and the arid Kalaburagi region. GFS significantly underestimates coastal and Ghats rainfall. For live maps, open VayuMet.
| District / City | Day 1–2 (mm) | Day 3–4 (mm) | Day 5–7 (mm) | Confidence |
|---|---|---|---|---|
| Bengaluru | 3–12 | 8–25 | 15–40 | Moderate |
| Mysuru | 3–10 | 8–22 | 12–35 | Moderate |
| Mangaluru (Dakshina Kannada) | 15–45 | 30–80 | 50–120 | Low–Moderate |
| Hubballi-Dharwad | 2–8 | 5–18 | 10–30 | Moderate |
| Belagavi | 3–10 | 8–22 | 15–40 | Moderate |
| Shivamogga | 8–25 | 15–45 | 25–70 | Low–Moderate |
| Kodagu (Coorg) | 20–55 | 35–90 | 55–130 | Low |
| Kalaburagi | 0–3 | 2–8 | 5–18 | Low–Moderate |
Note: GFS at 0.25° severely underestimates orographic rainfall over the Western Ghats. Coastal Karnataka (Dakshina Kannada, Udupi) and Kodagu (Coorg) regularly receive 2–4× GFS-indicated values during active monsoon spells.
The Karnataka coast is among India's wettest regions — Mangaluru averages ~3,600 mm and Agumbe in Shivamogga is often cited at ~7,000 mm annually. The SW monsoon arrives around 5–8 June — almost simultaneously with Kerala. Despite the 2026 below-normal national outlook, orographic enhancement ensures coastal Karnataka sees near-normal or adequate rainfall. GFS is not reliable for precise values here — use it only for timing guidance.
Bengaluru (930 m elevation) receives rainfall from both the SW monsoon and retreating NE monsoon. Onset of SW monsoon is around 10–15 June. Normal JJAS rainfall is 600–700 mm. El Niño years tend to delay onset by 3–7 days and reduce July–August totals. The 2026 outlook for Bengaluru is below-normal.
North Karnataka receives the least rainfall in the state — Kalaburagi and Bidar average 600–700 mm. This region is most vulnerable to El Niño suppression and carries elevated drought risk in 2026. Onset is around 20–25 June.