Mount Bromo records about 1600mm of rain across roughly 145 wet days a year, which is a 40% chance on an average day. December is the wettest month at 220mm (14% of the annual total) and July the driest at 20mm. Local rain type: thunderstorms. The dry season (May-October) is reliably clear for sunrise photography. The wet season brings dramatic afternoon thunderstorms but mornings can still be clear. Pack warm layers — it's cold at 2,300m.
Chance of rain on an average day: 40%
Rainfall climatology for Mount Bromo. The live hour-by-hour answer for today loads at the top of this page from Open-Meteo and refreshes through the day — the figures below describe a typical year, not today.
Conditions on this page are recalculated from the latest forecast every time it is opened, for the current date in the location's own time zone. Showing .
| Annual rainfall | 1600mm |
| Rain days per year | 145 |
| Odds on an average day | 40% |
| Wettest month | December — 220mm over 23 days |
| Driest month | July — 20mm over 2 days |
| Rain type | thunderstorms |
| Best dry window | June through September offers the clearest skies with virtually no rain — the dry caldera sand creates dramatic dust effects at golden hour. |
| Worst rain window | December through February brings torrential afternoon rains — road access from Probolinggo can be disrupted. |
December delivers 1000% more rain than July (220mm vs 20mm). That gap is the difference between planning around showers and ignoring them.
No single month holds more than 14% of the annual total, so rain in Mount Bromo is spread through the year — there is no season you can rely on being dry.
Mount Bromo rain arrives in short, heavy bursts — shelter and timing matter more than gear.
Rain falls on about 23 days in December against 2 in July — the frequency swing matters more for planning than the millimetre totals.
Climate normals. Use them to judge whether today's live forecast at the top of the page is typical or unusual for the season.
| Month | Rainfall | Rain days | Chance on a given day | Highs |
|---|---|---|---|---|
| January | 220mm | 23 | 77% | 22°C |
| February | 210mm | 22 | 73% | 22°C |
| March | 200mm | 21 | 70% | 22°C |
| April | 140mm | 15 | 50% | 21°C |
| May | 60mm | 6 | 20% | 21°C |
| June | 30mm | 3 | 10% | 20°C |
| July | 20mm | 2 | 7% | 20°C |
| August | 20mm | 2 | 7% | 20°C |
| September | 40mm | 4 | 13% | 20°C |
| October | 90mm | 9 | 30% | 21°C |
| November | 150mm | 16 | 53% | 21°C |
| December | 220mm | 23 | 77% | 22°C |
Rain probability is the chance that at least 0.2mm falls at your location — not how long it rains. For Mount Bromo we combine the hourly probability curve, expected volume in millimetres, and the city's own rainfall record into a single umbrella verdict.
| Factor | Weight | What it measures |
|---|---|---|
| Hourly probability | 40% | Peak and sustained chance of measurable rain across the next 24 hours. |
| Expected volume | 30% | Total millimetres, which separates a passing shower from a genuine soaking. |
| Timing & duration | 20% | When rain starts, when it eases, and the longest continuous dry window. |
| Local rain type | 10% | Drizzle, brief showers, thunderstorms or monsoon — each needs different gear. |
Live hourly values come from Open-Meteo and refresh through the day. Monthly rainfall figures are climate normals, so they describe a typical year rather than a forecast.
Mount Bromo records rain on roughly 145 days a year — about a 40% chance on any given day — totalling around 1600mm.
December, with about 220mm over 23 rain days. That is 14% of the entire year's rainfall in a single month.
July is the driest month at 20mm across roughly 2 days. June through September offers the clearest skies with virtually no rain — the dry caldera sand creates dramatic dust effects at golden hour.
The dry season (May-October) is reliably clear for sunrise photography. The wet season brings dramatic afternoon thunderstorms but mornings can still be clear. Pack warm layers — it's cold at 2,300m.
No. Probability is the chance that at least 0.2mm of rain falls at your location at some point in the period. Check the expected millimetres alongside it: 40% with 0.4mm is a passing shower, 40% with 12mm is a soaking.