Tbilisi has mildly warm humid subtropical climate. Typically winter is mildly cold and summer is hot. Average annual temperature is 12,7 °C; temperature in January is 0,9 °C and in July 24,4 °C.

The absolute minimum recorded temperature is −23 °C and the absolute maximum is 40 °C. Average annual precipitation is 560-mm. Wettest month is May (average 90-mm of precipitation) while January is driest (average 20-mm precipitation). Snow falls on average 15-25 days a year. North and northwesterly winds dominate throughout the year. Southeasterly winds are common as well.