KUALA LUMPUR, May 28 — Thunderstorms are forecast in parts of Perak, Terengganu, Pahang, Negeri Sembilan, Johor, Sarawak and Sabah until 9pm, the Malaysian Meteorological Department (MetMalaysia) said this afternoon.

Affected areas in Perak include Kerian, Larut, Matang dan Selama, Hulu Perak, Kuala Kangsar, Kinta and Kampar.

In Terengganu, the warning covers Kuala Nerus, Hulu Terengganu, Kuala Terengganu, Marang, Dungun and Kemaman.

Affected areas in Pahang are Jerantut, Temerloh, Maran, Kuantan, Bera and Rompin, while in Negeri Sembilan it involves Jelebu, Kuala Pilah, Jempol and Tampin.

The warning also covers Segamat and Mersing in Johor.

In Sarawak, the affected areas are Kapit, Bukit Mabong, Tatau, Sebauh and Limbang, while in Sabah it involves Kinabatangan in Sandakan.

MetMalaysia said the warning is issued when there are signs of thunderstorms with rainfall intensity exceeding 20mm per hour that are occurring or expected to occur for more than an hour.

The department said thunderstorm warnings are short-term alerts valid for no more than six hours from the time of issuance.