The Met Office yellow weather warning came into effect at 9am, telling residents to prepare for heavy showers and the chance of thunder.
This was originally set to expire at 6pm, but it has now been extended by the weather experts until 9pm.
The Met Office said that “frequent heavy showers and thunderstorms are expected for much of Saturday” and changed the end time at 4.51pm.
READ MORE: Met Office: What to expect amid thunderstorm warning
“Heavy showers and thunderstorms may lead to some disruption to transport and infrastructure,” the forecaster warned.
The thunderstorm warning covers Southampton, the New Forest and the majority of Hampshire.
“10-15 mm of rain could fall in less than an hour, whilst some places could see 30-40 mm of rain over several hours from successive showers and thunderstorms,” the Met Office said.
“Frequent lightning, hail and strong, gusty winds will be additional hazards.
“Give yourself the best chance of avoiding delays by checking road conditions if driving, or bus and train timetables, amending your travel plans if necessary.”
