Karnataka changes climate three times between the sea and the plateau

The escarpment does the work

Karnataka is arranged in bands running roughly parallel to the coast. There is a narrow, humid coastal strip around Mangaluru, Udupi and Karwar. Behind it the land rises abruptly into the Western Ghats, a belt of steep forested hills that includes Kodagu, Chikkamagaluru and the country around them. Beyond the crest the ground opens out into the Deccan plateau, where Bengaluru, Hampi, Badami and most of the state’s population sit.

The bands exist because of what the escarpment does to moving air. Moisture coming in off the Arabian Sea in the monsoon months is forced upward when it meets the hills, cools as it rises, and drops most of its water on the seaward slopes. What passes over the top is drier air with far less left to give, and the plateau receives a fraction of what the hills just west of it do.

That is not a small difference. It is the difference between a place where annual rainfall is measured in metres and a place a few hours away where it is measured in a few hundred millimetres. Every practical question about travelling here comes back to which side of that line you are on.

The coast and the hills share a monsoon, and it is a serious one

From June through August the coastal strip and the Ghats take the full force of the southwest monsoon. Roads are open and life continues, but this is rain at a volume that reorganises the day rather than interrupting it, and prolonged spells bring the same slope-stability problems that affect the Ghats all the way down the peninsula.

Coffee country in Kodagu and Chikkamagaluru is at its most photogenic in the wet and in the weeks immediately after, when the streams are running and the hills are properly green. It is also misty enough that a viewpoint may deliver nothing but white air, and leeches are a genuine feature of walking in that forest rather than an exaggeration.

The most rewarding compromise for this belt is usually the tail of the season and the month or two following it. The water is still moving, the greenery has not burnt off, the mist has thinned, and the roads have had time to be cleared and patched. By February the hills are drying, and by April they are noticeably brown.

The plateau has a completely different problem

On the dry side of the Ghats the monsoon is a modest affair and the defining constraint is heat. Hampi, Badami, Bijapur and the northern plateau towns are severe from March to May, and the ruins that make them worth visiting offer very little shade at the hours you would most want it. Granite radiates heat back at you long after the sun has moved off it.

Winter is the obvious season for this half of the state — clear, dry, warm in the afternoon and cool at night, with the low sun that makes the stonework worth photographing. The weeks after the monsoon are good too, and briefly green, though the plateau greens modestly compared with what is happening a hundred kilometres west.

Bengaluru sits at enough elevation to escape the worst of it and has a reputation for mildness that is largely deserved, though it is warmer in April than the reputation suggests, and its monsoon is a pattern of heavy evening downpours rather than a continuous wet season.

One state, two seasons, and the trap in between

The trap is an itinerary that strings the coast, the hills and the plateau together in a month that suits only one of them. In July that means a superb week in the coffee hills followed by three days in a hot, hazy interior with little rain to show for it. In April it means comfortable plateau mornings and a hill belt that has lost the water it is famous for.

If a trip must include all three, the shoulder months are the honest answer. Late in the year, once the rain has retreated, everything on the list is at least good, even if nothing is at its individual peak. That is usually the better trade for a visitor with one attempt at it.

The alternative is to pick a band and travel it properly. The coast alone, from Karwar down to Mangaluru, is a fortnight’s worth of country. So is the Ghats belt. Trying to do the whole cross-section in five days mostly produces a lot of driving on ghat roads, which are slow by design.

What the wildlife calendar adds

The state has a substantial set of protected areas along and behind the Ghats, and they follow the general Indian pattern: closed or heavily restricted during the monsoon, open through the dry season, best for sightings in the hot months when water has become scarce and animals have to travel to it.

That pushes against the comfort calendar in the usual way. March to May is when the forests are most rewarding and least pleasant, and December to February is when they are most pleasant and moderately rewarding. Neither answer is wrong; they are optimising different things.

As everywhere, opening dates, permitted zones and booking arrangements change and are set locally, so confirm the current position with the relevant forest department rather than assuming last year’s arrangements still hold.