Maharashtra
Mumbai and Maharashtra have a tropical climate, with a dry season (winter) from October to February, followed directly by summer from March to June. Winter is the most pleasant season, with temperatures hovering around 30°, while from March to May, the climate becomes much wetter and the thermometer climbs to 45°! Thunderstorms and pre-monsoon rains are common from early June. The south-west monsoon then reaches Maharashtra around mid-June and lasts until September. Life is then punctuated by heavy downpours, flooding is rife and transport operations (trains, buses, cars, auto-rickshaws) are considerably affected. The rains are even heavier in the northern part of the Western Ghats.
Best time to visit Mumbai and Maharashtra: October to March.
Goa
The small state of Goa, bordered by the ocean, enjoys a pleasantly sunny, warm and humid climate from October to May. Temperatures are constant, ranging from 20° to 32° all year round. The sea-swept coastline has an even drier climate than the rest of the state. The monsoon season sets in everywhere from June to September, with most resorts closing and tourist numbers dropping drastically. It is, however, a rather poetic season, favored by Indian tourists who come to recharge their batteries in the hinterland to admire the rain on the verdant landscapes and enjoy Goa's legendary nonchalance.
Best time to visit Goa : October to April.
Karnataka
Karnataka is a very large state, with varied topography and consequently different climates. There are three main regions: the coast, the northern interior and the southern interior. The coastal region of Karnataka has a tropical climate, subject to an intense south-west monsoon from June to September. The northern inlands (Hampi, Bidar, Bijapur) are subject to an arid climate and receive little rainfall during the monsoon season. The climate is dry and hot. The southern interior (Bangalore, Mysore, Hassan) is semi-arid, with average monsoon rainfall. Temperatures are pleasant from October to April. The Western Ghats of Karnataka have a more moderate climate, and showers are more frequent due to altitude and denser vegetation.
Best time to visit Karnataka: November to March.
Kerala
This state, which stretches along the southwest coast to the southern tip of India, has a humid climate favored by its proximity to the ocean and the rainforests of the Western Ghats. The monsoon season hits Kerala hard from the beginning of June to the end of August, with frequent flooding, landslides and slow-moving traffic. From September onwards, rainfall eases off but remains heavy. October and November still see sporadic showers, but the climate is already becoming less humid and warmer. From December to February, the weather is generally dry and sunny. From March onwards, temperatures and humidity levels rise, until the monsoon season arrives in June. The Western Ghats, however, are much wetter than the coastline, and temperatures are milder, sometimes even cooler at night.
Best time to visit Kerala: November to April.
The East Coast: Tamil Nadu, Telangana & Andhra Pradesh
The country's east coast has a tropical climate, with high temperatures all year round. From January to March, there is little rainfall, the days are sunny and temperatures oscillate between 20° and 30°. In April and May it starts to get much hotter. From June to September, the thermometer can reach 37° and sporadic showers are frequent. The northeast monsoon arrives in early October and lasts until the end of December. Rainfall is heavy, but there is little flooding in this area, with a few exceptions (Chennai in particular).
Best time to visit the east coast: January to September.
Andaman and Nicobar Islands
The archipelago has a pleasant tropical climate, hot but tempered by the presence of welcome sea breezes. Rainfall is frequent but light during the southwest monsoon, from June to September, and the northeast monsoon, from November to January. March to May are the hottest months.
Best time to visit the Andaman and Nicobar Islands: mid-November to April.
