Assessment of rainfall for May 2023 showed that positive rainfall anomalies (50 to 150 mm) were observed over extrem Eastern part of Indonesia, Southern part of the Philippines and East of Brunei. However, near normal range (50 to -50 mm) were observed in most parts of the Philippines, Central part of Myanmar, Southern part of Thailand, Singapore, West and Central part of Indonesia, North of Laos, West of Cambodia, Malaysia and Southern of Vietnam. Furthermore, the rest of the ASEAN region are within the negative rainfall anomalies (-50 to -150 mm).