Tempo vs. clima

In Italian, both 'tempo' and 'clima' can refer to weather, but they are used in slightly different contexts.

Tempo

'Tempo' refers to the day-to-day weather conditions or the current state of the atmosphere.
Che tempo fa oggi?
(What's the weather like today?)
Il tempo è bello questa settimana.
(The weather is nice this week.)
Le previsioni del tempo indicano pioggia per domani.
(The weather forecast indicates rain for tomorrow.)

Clima

'Clima' refers to the long-term, average weather conditions in a specific area or region.
L'Italia ha un clima mediterraneo.
(Italy has a Mediterranean climate.)
Il clima tropicale è caratterizzato da temperature elevate tutto l'anno.
(Tropical climate is characterized by high temperatures all year round.)
I cambiamenti climatici stanno influenzando il clima globale.
(Climate change is affecting the global climate.)

Summary

While 'tempo' is used for current or short-term weather conditions, 'clima' refers to the overall, long-term weather patterns of a region. Use 'tempo' for daily weather discussions and forecasts, and 'clima' when talking about general weather characteristics of an area over time.