You’ve probably heard people joke that Houston has two seasons: hot and slightly less hot. If you're looking at a weather app and trying to make sense of Houston weather in degrees Celsius, the raw numbers only tell half the story.
Honestly, the "real feel" here is a whole different beast.
I’ve lived through Augusts where the mercury hits 35°C, but because the humidity is sitting at 80%, it feels like you're walking through a bowl of warm soup. It's thick. It’s heavy.
But then, January rolls around. Suddenly, it’s a crisp 15°C and the city feels completely transformed.
The Reality of Houston Weather in Degrees Celsius
Most people coming from Europe or Canada see a forecast of 28°C and think, "Oh, that’s a lovely summer day." In Houston, that’s basically a Tuesday in April.
If you want to understand the rhythm of this city, you have to look at the averages, but also the weird extremes that have been popping up lately. According to data from the National Weather Service, Houston is actually seeing a massive shift in its winter patterns. Just this month, in January 2026, we've already broken multiple record highs.
A Month-by-Month Breakdown
Let’s get into the nitty-gritty. If you’re planning a trip or just trying to figure out when to turn off your AC (spoiler: almost never), here is how the temperature typically shakes out in Celsius.
January and February
These are the "wild card" months. You might wake up to a chilly 6°C and be wearing a t-shirt in 22°C weather by 3 PM. Usually, the average high sits around 17°C, which is actually quite pleasant. But don't let that fool you. We get these "Blue Northers"—cold fronts that drop the temperature 10 degrees in an hour.
March and April
This is the sweet spot. Seriously. Highs hover between 23°C and 26°C. The humidity hasn't quite reached "suffocating" levels yet. It's the only time of year you'll see Houstonians voluntarily sitting on outdoor patios without a commercial-grade fan pointed at their faces.
May and June
This is the transition into the "Big Heat." June typically sees averages of 32°C. It’s also statistically the wettest month, averaging about 150mm of rain. That rain doesn't cool things down, though. It just turns the city into a giant steamer basket.
July and August
The gauntlet. August is consistently the hottest month. You're looking at daily highs of 35°C, but the dew point is so high that the heat index frequently pushes the perceived temperature past 42°C. If you aren’t near a pool or an industrial-strength air conditioner, you’re going to be miserable.
September and October
September is just "August Part 2." It stays around 32°C. But October? October is the reward for surviving the summer. The temperature finally dips back to a manageable 27°C, and the air starts to feel dry again.
November and December
Mild and erratic. Averages are around 19°C. It’s great for the holidays, though you'll occasionally see people wearing shorts with a Santa hat because it’s 25°C on Christmas Day.
Why the Dew Point is Your Real Enemy
When you're checking Houston weather in degrees Celsius, the number you actually need to care about is the dew point.
In most parts of the world, 30°C is just hot. In Houston, 30°C with a dew point of 24°C is dangerous. When the air is that saturated with moisture, your sweat doesn't evaporate. Your body's natural cooling system basically breaks.
Dr. Melissa Huffman from the National Weather Service has often pointed out that the Gulf of Mexico acts like a giant heater and humidifier for the city. Since the Gulf is currently running at record-warm temperatures in early 2026, we’re seeing more "tropical" nights where the temperature doesn't even drop below 25°C at 3 AM.
Survival Strategies for the Houston Climate
Living here requires a specific set of skills. It’s not just about drinking water; it's about timing your entire existence.
- The 10 AM Rule: If you have errands that involve being outside, do them before 10 AM. After that, the sun becomes a laser beam.
- The "Second Shirt" Strategy: Many professionals in Houston keep a spare shirt in their car. If you have to walk more than five minutes from a parking lot to an office in July, you will be drenched.
- AC Maintenance: In Houston, your HVAC system isn't a luxury; it's life support. Most residents get theirs serviced in March before the first 30°C day hits.
- Hydration is Prose: You need electrolytes, not just tap water. The salt loss from sweating in 35°C heat is no joke.
The Impact of a Changing Climate
We can't talk about Houston weather without mentioning how much it's changed. Climate Central reports that Houston's average winter temperature has risen by nearly 2.4°C over the last few decades.
This means fewer "hard freezes" (below 0°C) and many more days where the temperature sits in that weird, humid 20-25°C range during months that used to be cold. While it sounds nice to avoid the snow, it actually messes with the local ecology. Pests like mosquitoes and termites don't die off in the winter anymore. They just... wait.
Actionable Steps for Dealing with Houston's Heat
- Download a "Heat Index" App: Don't just look at the Celsius. Look at the "Feels Like" temperature. If it's over 40°C, limit your outdoor time to 15-minute bursts.
- Invest in Ceramic Window Tint: If you drive, this is a game-changer. It can drop the interior temperature of your car by 10 or 15 degrees when parked in the Texas sun.
- Watch the Tropics: From June to November, the weather isn't just about heat; it's about the Gulf. Use sites like Space City Weather for "no-hype" forecasts that focus on actual data rather than clickbait scares.
- Use Dehumidifiers: Inside your home, keeping the humidity below 50% makes 24°C feel like 20°C. It saves money on your electric bill because you won't feel the need to crank the AC down to 18°C just to feel comfortable.
The reality is that Houston is a sub-tropical swamp that decided to become a global energy hub. It’s vibrant, it’s diverse, and it’s incredibly hot. But once you learn to read the Celsius numbers through the lens of humidity, you can actually enjoy the unique rhythm of the Bayou City.