The Weather at Lake Chapala: Sunshine, Dry Air, and the Lake That Keeps It Gentle

Ask anyone who has moved to Lake Chapala what made them stay, and the weather comes up within a minute. Usually it comes up first. People arrive for the cost of living or the community or a friend who would not stop talking about it, and then one ordinary Tuesday in February they are eating lunch on a terrace in short sleeves, under a sky with nothing in it, and they understand.

Below is what that weather is like across a whole year, with real numbers, because the honest version is better than the brochure. After that comes the why. Once you see how the latitude, the altitude and the lake work together, the climate stops feeling like luck and starts feeling like something you can count on.

The short version

• Afternoons average between about 72°F in January and 86°F in May, the warmest month.
• Nights average between about 52°F and 63°F all year. You sleep with a window open and a light blanket.
• Rain is seasonal. Around 92 percent of it falls between June and October. From November through May the town averages a rainy day or two a month.
• Sunshine is the default. Guadalajara, the closest long sunshine record, logs around 2,670 hours a year, several hundred more than Chicago and far more than Seattle or Vancouver.
• The air is dry for most of the year, so warm days do not feel sticky and evenings cool off quickly.
• Most houses have no heating and no air conditioning, and most people never miss either one.

What the numbers say, month by month

These are the official normals from Mexico's national weather service for the Chapala station, which sits on the lakeshore at about 5,050 feet. Ajijic is a few miles west on the same shore at the same height, and its weather is essentially the same.

Source: Servicio Meteorológico Nacional, Normales climatológicas 1951–2010, station 14040 Chapala. Fahrenheit converted and rounded.

Look at the high column for a moment. The gap between the coolest month and the warmest is fourteen degrees. In Chicago that gap is closer to fifty. Here, the difference between winter and summer is mostly about whether it rains in the evening, not about what you wear.

Why it is like this

The latitude

Lake Chapala sits at about 20 degrees north, inside the tropics, on the same line as Hawaii's Big Island. The sun stays high in the sky all year and the length of the day barely changes, from roughly eleven hours of daylight in December to roughly thirteen in June. There is no long dark winter here, and no evening in January when the sun is gone by five.

The altitude

A tropical latitude at sea level gives you Puerto Vallarta: beautiful, and hot and humid for much of the year. Lift that same latitude to 5,000 feet and the air is thinner, drier and cooler. The days keep the tropical sun while the heat and the humidity fall away, and the nights cool down properly because thin, dry air does not hold the day's warmth for long. Most of what people love about the climate here is that combination: tropical sun with highland air.

The lake

Lake Chapala has been Mexico's largest freshwater lake since the early seventeenth century. It runs about 50 miles east to west and covers roughly 420 square miles when it is full, which is a great deal of water sitting right in front of every town on the shore.

Water warms and cools much more slowly than land. Through the hot spring months, the lake takes the edge off the afternoon, and on winter nights it gives a little warmth back. The clearest way to see it is next door. Guadalajara sits at nearly the same altitude, about 45 minutes to an hour away, with no lake. Its average May afternoon is around 89°F against Chapala's 86°F, and its days swing further from morning to afternoon all year. Three degrees does not sound like much until you are standing in it in May.

The lake is also shallow for its size, averaging only about 23 feet deep, so it does not act like a deep ocean that holds one temperature all year. It acts more like a very large cooling surface. On many afternoons you can feel the breeze come off the water, and on the north shore, where Chapala, Ajijic and San Juan Cosalá sit with the mountains at their backs, the towns face south into the sun with that open water in front of them.

The sunshine

Guadalajara's long-term record shows around 2,670 hours of sunshine a year, and the lakeshore, under the same sky, gets much the same. For comparison, Chicago gets about 2,500 hours, Seattle about 2,170 and Vancouver about 1,940. The sunniest stretch is the dry spring, with May alone averaging close to 280 hours of sun.

What the numbers do not capture is how the sunshine is spread across the year. Back home, most people get their good weather in a block, and then winter arrives and takes it away for months. Here the bright days are spread across every month. Even in the rainy season, the typical day starts clear and stays that way until the clouds build in the afternoon. Many people find that the steady light changes their mood more than any other single thing about the move. Mornings are easier when the sun is already up and the sky is already blue.

One practical note: the sun at 5,000 feet and 20 degrees north is strong. A hat and sunscreen are part of everyday life here, even on a cool January morning when it does not feel warm.

The dry air

For most of the year, from November through May, the air is dry. Guadalajara's records put the average relative humidity in the high 40s and 50s through the dry spring, and the lakeshore follows the same seasonal pattern. In practice that means an 84°F afternoon in April feels comfortable in the shade, laundry dries on the line in an hour or two, and the evening cools off fast enough that you want a sweater by nine.

The rainy months are a different season. The humidity climbs into the 70s, and the afternoon storms keep things damp. But the temperature drops at the same time, which is why July and August are cooler than May, and the nights stay fresh. It is a green, humid summer at 79°F, not a steamy one at 95°F.

The year as you actually live it

December through February: the dry, cool season

This is when the snowbirds arrive, and it is easy to see why. Afternoons sit in the low to mid 70s under clear skies, and almost no rain falls. Mornings are crisp, sometimes in the upper 40s on the coldest days, and that matters more than visitors expect, because houses here are built of brick and tile with no insulation and no central heat. You will wear a sweater at breakfast and short sleeves at lunch.

March through early June: the warm, dry season

The days lengthen and warm, and May is the hottest month of the year, with afternoons in the mid 80s. The hills dry out to gold and brown, it gets dusty, and everyone starts watching the sky for the first storm. It is the one stretch of the year when a ceiling fan earns its keep. Nights still drop into the low 60s, so even the hottest month here has cool sleeping weather.

Mid-June through September: the rainy season

The first big storm usually arrives in June, and the change is fast. Within a couple of weeks the brown hills turn a deep, almost unreal green and the lake starts to rise. The rhythm of a typical day is simple: a sunny morning, clouds building after lunch, and rain in the late afternoon or overnight, often with thunder rolling across the water. Many long-time residents will tell you this is their favorite time of year, and I understand why. The air smells clean and everything is growing.

October and November: the green dry-down

The storms taper off through October while everything is still green, the skies clear and the temperature settles into the high 70s. If someone asks me when to visit for the first time, this is often what I suggest, because it shows the lake at its most beautiful.

What great weather changes about daily life

People stay for what the weather lets them do every day without planning for it.

Life here happens outside. Houses are built around patios, terraces and covered portales, and many families spend more of the day on the terrace than in the living room. Breakfast is outdoors. Friends come over and sit in the garden until dark. The plaza in Ajijic, like the one in the photo at the top of this article, is full on an ordinary weekday because it is a pleasant place to be on most days of the year.

You walk more. The malecón, the market, the café, the walk home after dinner all stop depending on whether it is too hot or too cold. The Wednesday tianguis in Ajijic happens in the open air almost every week of the year. Something is always in bloom, from the bougainvillea and birds of paradise that flower most of the year to the jacarandas that turn the streets purple in spring, and the hummingbirds follow them.

The weather also changes your budget. With no furnace and no air conditioner, the bills that dominate a household in Minnesota or Arizona mostly disappear. That does not mean utilities are free, and I explain the exceptions in my utilities guide, but the climate is doing a lot of the work.

And it simplifies your life. One wardrobe covers the whole year, with a sweater, a light jacket and an umbrella for the summer. There is no shoveling, no ice on the windshield, and no season you have to get through. Every month has something worth getting up for.

About “the second-best climate in the world”

If you research the area for any length of time, you will read that National Geographic ranked Lake Chapala as having the second-best climate in the world, usually after Nairobi. It is repeated on real estate websites, in relocation guides and at dinner parties.

I am not going to repeat it as fact, because nobody has ever produced the article. Geographer Tony Burton went looking and asked someone with access to the Society's records, who found no mention of Chapala's climate. Columnist Dale Palfrey searched for it in the Guadalajara Reporter in 2016 and came up empty, and Mexico News Daily revisited the claim in 2025 with the same result. As far as anyone can tell, it is a story that got passed around because it sounded right.

It is true that the weather here is among the most comfortable anywhere, and the reasons are in the numbers above. It does not need a magazine ranking, and you will know within a week of arriving.

What to know before you move

• Winter mornings are colder indoors than outdoors. Uninsulated houses hold the night chill. A good blanket, a sunny terrace and a house that faces south make a real difference.
• Roofs need sealing before the rains. Most roofs are flat and rely on a waterproof coating called impermeabilizante. It is renewed every few years, and May is the time to do it, not July.
• Damp closets in the rainy season. Leather and books can pick up mildew in August. Airflow and a dehumidifier in the closet solve most of it.
• The spring is dusty. In the driest weeks before the rains, dust and sometimes smoke from fires in the hills can haze the view across the lake. It clears with the first storms.
• Respect the sun. At this altitude and latitude, wear a hat even on cool days. Visitors who skip it on a January walk along the malecón usually regret it by evening.

A note on the numbers in this article

Temperature and rainfall figures are the Servicio Meteorológico Nacional's 1951–2010 normals for the Chapala station, the official long-term record for the lakeshore. Sunshine and humidity come from Guadalajara's records, because no equivalent long series is published for the lakeshore, so treat them as a close neighbor's figures rather than our own. The Guadalajara comparison uses its 1991–2020 normals, a different period, so read it as a general pattern and not a precise measurement. Comparison cities use their published long-term averages. Any single year can be wetter, drier, warmer or cooler than these averages, and I am a real estate agent, not a meteorologist.

Come and feel it

No article does this justice. The best way to understand the weather here is to sit in the plaza on a February afternoon or watch a summer storm roll across the lake from a covered terrace. If you would like to try it for a season, my rentals are always current, and renting before you buy explains how I would approach it. If you already know this is where you want to wake up, my listings are here, and you can always write to me or send a WhatsApp. I am happy to tell you which neighborhoods catch the morning sun.