Average Summer Weather in Mumbai, India: Temperatures, Rainfall, and More

Mumbai’s summer weather really shapes daily life here, from deciding when to step out to picking the right time for a walk along the city’s coastline. The season brings long, hot stretches, sticky humidity, and the dramatic arrival of the monsoon. Daytime temperatures usually hover between 30 °C and 34 °C (86 °F to 93 °F), and nights almost never cool off below 25 °C (77 °F).

What stands out about Mumbai’s summer is the sudden shift from hot, dry days in May to heavy, pounding rain in June and July. The monsoon brings intense, quick downpours that can flip the city’s mood in an instant. The Arabian Sea does its bit, too, keeping coastal neighborhoods a little cooler than the city’s inner areas.

If you know these patterns, you can plan better—maybe you’ll catch some early summer sunshine or brace for the monsoon’s wild side. When you understand the swings in temperature, rainfall, and humidity, you can get through the season with fewer hassles.

Overview of Mumbai’s Summer Climate

Mumbai’s summer means high humidity, plenty of rain, and steady warmth. The city’s location by the sea and its tropical vibe set the tone for its weather, with monsoon rains stealing the show.

Tropical Climate Characteristics

Mumbai has a tropical climate, so you’ll notice warm weather all year and a clear split between wet and dry times. In summer, daytime temperatures usually sit between 86°F (30°C) and 91°F (33°C), and nights rarely dip below 78°F (26°C).

Humidity hangs around almost 100%, making the air heavy and damp. This means even moderate heat can feel much worse. Since Mumbai hugs the Arabian Sea, temperatures don’t swing much between day and night.

Rain really defines summer here. By July, you might see over 20 inches of rain in just a month. Streets flood fast, and travel slows down. Still, the rain brings relief from the heat and keeps the city green.

Köppen Climate Classification

Mumbai fits into the tropical wet and dry (Aw) and tropical monsoon (Am) categories in the Köppen system. The city shifts from a dry winter to a super wet summer.

The mean annual temperature sits around 27–28°C (81–82°F), and you won’t notice big changes between seasons. What really changes is the rain. The wet season runs from June through September, with July as the rainiest month.

Mumbai almost never feels “cool” like temperate cities do. Even in the driest months, it stays above 18°C (64°F). The climate stays steady, which is nice if you like predictability, but tough if you’re not used to high humidity.

Seasonal Weather Patterns

In summer, daily highs drop from about 91°F (33°C) in June to 86°F (30°C) in August. Nights stay warm, rarely falling below 76°F (24°C). As the season goes on, cloud cover rises from 58% in early June to over 70% by August.

Rainfall jumps as the monsoon gets going. June brings about 8 inches of rain, and by mid-July, you could see totals over 23 inches in a 31-day stretch. The odds of a wet day go from 31% in June to nearly 60% in August.

Winds blow in from the west, averaging around 12 mph, pulling moist air from the sea. Sea temperatures stay warm, between 82–86°F (28–30°C), which just adds to the muggy feeling. Days get a little shorter as summer goes on, and sunsets come earlier by late August.

Average Summer Temperatures in Mumbai

Summer in Mumbai means steady warmth and barely any break from the humidity. Temperatures don’t change much month to month, but the difference between day and night can really affect how you feel. Extreme heat isn’t common, but the mix of heat and moisture makes things feel hotter.

Monthly Temperature Breakdown

Mumbai’s summer runs from June through August, right when the monsoon takes over. Average highs drop from about 91°F (33°C) in early June to around 86°F (30°C) by late August.

Nighttime lows slide from 82°F (28°C) in June to about 78°F (26°C) in August. This small range comes from the city’s coastal location, which keeps temperatures steady.

Here’s a quick look:

As clouds and rain increase, temperatures drop a bit. Still, the air stays warm and humid the whole time.

Daytime and Nighttime Averages

During summer days, temperatures usually stay between 85–91°F (29–33°C). Thanks to high humidity, the heat index feels even higher, especially in June before the heavy rains.

At night, it almost never falls below 76°F (24°C). So, don’t expect much relief after sunset. The air stays muggy, and most people need fans or AC to sleep comfortably.

Tropical coastal cities like Mumbai have a small gap between day and night temperatures. The Arabian Sea keeps things stable, so you get steady warmth instead of big swings.

Temperature Extremes During Summer

Mumbai doesn’t see much extreme heat compared to inland India. Summer highs rarely go above 93°F (34°C), and lows almost never drop below 76°F (24°C).

The hottest stretch usually hits in early June, before the monsoon clouds gather. By August, with all the rain and clouds, it’s a bit cooler.

The numbers might not look extreme, but the constant 100% muggy conditions make the weather feel hotter than the thermometer says. That’s what really defines summer in Mumbai.

Rainfall Patterns and Monsoon Impact

Mumbai’s summer weather really depends on the southwest monsoon, which brings heavy rain, high humidity, and frequent flooding. Rain doesn’t fall evenly—it peaks in certain months, changing how you get around and what you can do outside. Knowing when the rains hit and how much to expect helps you plan.

Onset and Duration of Monsoon

The southwest monsoon usually sweeps into Mumbai in early June. The first showers show up suddenly after weeks of rising heat, cooling things off a bit but making it even more humid. This is when the wettest part of the year starts.

Rain keeps coming through September, but how hard it falls changes each month. July usually brings the most intense downpours, while June and August also see plenty of rain. By late September, the monsoon backs off, and October dries out fast.

The monsoon lasts about four months. During this stretch, the city often faces flooding in low-lying areas, traffic jams, and delays on public transport. If you’re visiting, you’ll want to be ready for these surprises and those sudden, heavy showers.

Monthly Rainfall Totals

Mumbai’s summer rain mostly falls between June and September. Here’s what the averages look like:

July is by far the wettest, sometimes bringing more than a third of the season’s rain. August stays very wet, just not quite as wild. By September, rain drops off, and you know the monsoon’s almost done.

Mumbai gets about 2,100 mm of rain each year, with over 90% of it falling in these four months. That’s why flooding and waterlogging are such a big deal in summer.

Number of Rainy Days

Rainy days jump up fast once the monsoon starts. In June, you’ll get about 10 to 15 days with measurable rain. By July, that jumps to more than 23 days, making it the rainiest month.

August brings around 20 rainy days, and September averages 12 to 15. Outside these months, rain is rare, and from November to April, it barely shows up at all.

With so many rainy days, you’ll want to carry an umbrella or raincoat if you’re out and about. Even if it doesn’t rain all day, those quick, heavy showers can mess up your plans. The steady rain also means humidity usually stays above 80%.

Humidity and Sunshine Hours

In Mumbai’s summer, you’ll deal with high humidity and less sunshine. Both shape how comfortable it feels outside and how much daylight you get for sightseeing or errands.

Average Summer Humidity Levels

Humidity shoots up in Mumbai when the monsoon season starts in June. Levels rise from about 75% in early June to as much as 86% in July and August—the stickiest months.

High humidity with warm temperatures makes the air feel heavy and uncomfortable. Nights stay muggy, with barely any break from the daytime stickiness.

Here’s how humidity usually looks:

Because the air’s so moist, sweat doesn’t evaporate much, so moving around can feel draining. Light clothes and staying hydrated help a lot when you’re outdoors.

Sunshine Duration by Month

Mumbai’s summer also means less sunshine thanks to thick clouds. In June, you might get 5 to 6 hours of sun per day on average, but by July and August, that drops to just 2 to 3 hours daily—the lowest of the year.

With so little daylight, outdoor plans can get tricky. Mornings might give you a bit of clear sky, but afternoons often turn gray and rainy. If you’re hoping to see the sights, try to get out earlier in the day for a better shot at some sun.

Sea Temperatures and Coastal Effects

Mumbai’s spot on the coast shapes both how nice the water feels and how summer weather unfolds. The Arabian Sea stays warm all season, and that steady heat affects humidity, rainfall, and even the local winds.

Average Sea Surface Temperatures

In summer, sea surface temperatures around Mumbai usually sit between 28°C and 31°C (82°F to 88°F). Long-term satellite data shows the sea stays warm from May through September.

June typically feels hottest, with average water temperatures close to 30°C. February brings the coolest days, averaging around 25°C. The seasonal change is slow, so the sea almost never feels chilly for swimmers.

Here’s a quick look at how the temperatures shift through the seasons:

Since the sea barely dips below 27°C in summer, you’ll find the water feels a lot like a heated pool. That’s great for swimming and coastal activities, and it also affects the local climate.

Impact on Local Weather Conditions

Warm sea surfaces keep pumping moisture and heat into the atmosphere. This process drives the high humidity you notice every summer in Mumbai.

Humidity often sits above 70%. The air can feel heavy, even if the temperature isn’t at its highest.

The monsoon system draws power from these strong sea temperatures. The Arabian Sea’s warmth fuels rising air, which boosts cloud formation and rainfall. That’s why heavy showers hit hardest in June and July, right when the sea’s at its warmest.

Coastal winds react to the temperature difference between land and sea. During the day, breezes blow inland, bringing moisture that helps build up afternoon clouds. At night, the wind usually flips and heads back out to sea.

If you spend any time along the coast, you’ll notice how quickly the weather can change. One moment, a cool breeze, the next, sudden rainfall—both thanks to those warm waters.

Additional Weather Considerations in Summer

In Mumbai’s summer, there’s more to watch out for than just temperature and rain. Wind, air pressure, and the season’s timing all shape what you experience in the city.

Wind Patterns and Speeds

With the summer monsoon, Mumbai’s winds shift in a big way. From June through August, moist southwesterly winds take over, bringing heavy rain from the Arabian Sea.

These winds blow steadily, often at 15–25 km/h. They cool things down a bit but also crank up the humidity.

During intense rain or thunderstorms, gusts pick up and can make getting around pretty tough.

When the monsoon isn’t active, winds calm down and feel less humid. In May, for example, they’re usually milder, averaging about 10–15 km/h, before picking up again in June. If you’re planning to be outside, expect gentler winds in late spring and stronger, wetter gusts during peak summer.

Air Pressure Trends

Air pressure in Mumbai drops as the monsoon arrives. May usually starts higher, around 1006–1008 hPa, but by June and July, it falls to 1000–1004 hPa.

This seasonal low-pressure system pulls moist air inland, making conditions unstable.

Lower pressure means you’ll see more rainstorms. The changes aren’t dramatic, but they do shift daily weather.

Travelers should expect sudden changes in rainfall. Sometimes, a day starts out clear, but falling pressure hints that showers are coming. If you keep an eye on the pattern, you’ll have a better shot at staying dry.

Best Months to Visit Mumbai

If you want to dodge the heaviest rains, plan your trip outside the peak monsoon. November through April gives you the driest and most comfortable weather.

Temperatures stay warm, and rainfall barely shows up, so sightseeing and outdoor stuff get a lot easier.

During the summer, May feels a bit better than June through August. Sure, May gets pretty hot, but it doesn’t get slammed with rain like July does.

In July, rain can dump over 800 mm in just one month.

If you’re thinking about hitting the beach, the water stays warm all year, usually between 25°C and 30°C.

But watch out—July and August bring heavy surf and a real risk of flooding, so it’s smarter to plan coastal trips before or after the monsoon hits its peak.

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