The Southern Regional Hydro-Meteorological Centre said HCM City and surrounding provinces would see sunny intervals during the day, followed by scattered showers and thunderstorms in the afternoon and evening
Temperatures are expected to range from 25-28 degrees Celsius overnight to 31-34 degrees during the day, with some areas exceeding 35 degrees.
Thunderstorms on Friday brought 10-30 mm of rain to many parts of HCM City and neighbouring localities, with some areas receiving more than 30 mm.
Rainfall is expected to increase in the coming days as upper-level wind convergence persists over the region, bringing moderate to heavy showers in some areas, accompanied by lightning, strong winds and possible whirlwinds.
From late June, the southwest monsoon is forecast to intensify, triggering a broader spell of wet weather across southern Vietnam.
Meteorologists warned that heavy rain could cause localised flooding in low-lying areas and disrupt transport.