In Tibet, the Tibetan calendar lags approximately four to six weeks behind the solar calendar. For example, the Tibetan First Month usually falls in February, the Fifth Month usually falls in June or early July and the Eight Month usually falls in September.
Losar
The Tibetan calendar is a lunisolar calendar. Losar is celebrated on the first three days of the first lunar month.
References
Tibetan festivals Wikipedia(Text) CC BY-SA