Climate and Clothing
The period between October and February is the most pleasant time to visit Bombay, when the city enjoys a balmy season of blue skies and a cool breeze. From March, the temperature gradually rises and the humidity reaches saturation point. It is very hot just before the monsoon rains break in mid-June. The rains last until September. They come as a welcome relief to Bombayites but when the drainage system fails everyone encounters difficulties getting around town. After the initial few days of flooded roads, however, Bombayites take the downpours and regular drenching in their stride. In September, the humidity and temperature begin to fall. Luckily Bombay does not suffer from the incessant power cuts that plague other parts of India, so offices and hotels remain air-conditioned and bearable through the hot months.

Most medicines are available in Bombay, but it is always sensible to take a small reserve stock of any prescription drugs. You may also want to put together a basic medical kit in advance of departure; this could usefully include something against 'Delhi Belly', antiseptic cream, lip salve, mosquito repellent and soothing cream for bites, suntan lotion for long days on Goa's beaches, water purification tablets if bottled water is not available and elastoplast. Some travelers develop a problem on their second or third day in India because of a lack of acclimatization or heat exhaustion, rather than a reaction to the change in food and water. They are advised to drink lots of fluids (water with a little salt and sugar) and keep to a diet of rice and yoghurt for a couple of days to give their system time to adjust. If an upset stomach persists, seek medical advice (tourist-class hotels have a doctor on call).

There are a few things not to do which will make your stay more enjoyable. Never drink tap water (the flasks in hotel rooms contains filtered water and bottled water is now available almost everywhere). Avoid salads, even in hotels, and do not eat the street food until you know how much you can afford to abuse your body for the sake of your palate.

Time Zone
Despite its size, India has a single time zone. It is 2-1/2 hours behind Hong Kong and Singapore, 5-1/2 hours ahead of London (GMT), 4-1/2 hours ahead of British Summer Time, 10-1/2 hours ahead of New York and 13-1/2 hours ahead of San Francisco.