This is a regular verb. It follows the conjugation pattern of the verb falar.
In Brazil, this verb is very common in informal speech, meaning to freak out or lose emotional control. In both Brazil and Portugal, it is also used in clinical or psychiatric contexts to describe a psychological episode.
Present:
Ela surta toda vez que tem prova.
She freaks out every time there's a test.
Preterite:
O paciente surtou durante a noite.
O doente surtou durante a noite.
The patient had a psychotic episode during the night.
Negative Imperative:
Não surta; está sob controle.
Don't freak out; it's under control.