Do your characters need to wear fluffy winter coats when it gets cold, or can they pass with a thin jacket? Is summer like stepping into an oven? Or is summer actually winter?
I always get turned around when, during summer, people living below the equator tell me it's cold. I'm over here like "COLD??? It's SUMMER...oh wait, right. It's backwards down there."
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What is the climate like? Describe it.
Here are some ideas.
Cold: cool, chilly/crisp, freezing/below zero, hypothermia, dangerously deadly.
Hot: warm, toasty, sweltering, burning/scorching, heatstroke/fainting, dangerously deadly.
Damp/humid/drenched/drowning/soggy. Dry/arid/parched/chapped lips.
Moderate, balmy, comfortable.
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Whatever level of your world's or your specific country's tech, if your characters get cold, they might like to be warm instead. So, you might want to know if where they are or will be going is cold or not.
Is it necessary to build a fire or can they survive without?
On the flip side, do they need to be careful of heatstroke?
Maybe some climates are so harsh that no one can survive? Imagine, pollution or too-high oxygen levels. That can come into play.
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Climate can also affect #11 Occupations. For example, those people harvesting ice in the beginning of Disney's film Frozen.
It can also affect #14 Fashion especially if your characters are living in or will be going to a place that is always some extreme like humid, hot, freezing, or arid. And, you might have guessed it, climate affects #34 Crops & Livestock and #35 Transportation.
Arid places might grow olives, but humid climates can grow mangoes or coconuts, for example. You might travel on camel through deserts but boat through humid marshlands.
If you want to get specific about seasons, go to #25 Seasons.
Climate really affects so many aspects of our lives. If you think about it, it's actually quite shocking :O Even what we eat! (#16 Food).