(あたた)かい

あたたかい
adjective (i-adjective)
warm
1. warm (weather, temperature)
Describes pleasantly warm weather or temperature. Written 暖かい for weather/climate.
今日(きょう)(あたた)かいです
It's warm today, isn't it?
(はる)(あたた)かくなります
It gets warm in spring.
I want to rest in a warm room.
この(くに)一年(いちねん)(じゅう)(あたた)かいです
This country is warm all year round.
Even though it's winter, the warm days continue and it doesn't snow at all.
2. warm (feeling, personality)
Describes a warm, kind personality or warm feelings. Can also be written 温かい for this meaning.
(あたた)かい家族(かぞく)です
They are a warm family.
Thank you for your kind words.
I was happy about everyone's warm feelings.
He is a warm person and is always helping others.
The people in this town are very warm, and they helped me a lot when I moved here.

(あたた)かい (with (だん), meaning 'warmth') is used for weather and climate. (あたた)かい (with (おん), meaning 'temperature') is used for warm objects, food, or figuratively for warm personalities. Both are read あたたかい. Also commonly shortened to あったかい in casual speech.