A red weather warning comes into force at 10am and remains in place until 3pm.
Storm Eunice is expected to bring ‘dangerous’ weather with speeds of up to 70mph predicted for Portsmouth at around 11am.
An amber weather warning is also in place until 9pm.
The Met Office has warned that there is a ‘danger to life’ due to the storm.
On its website, the forecaster says: ‘Storm Eunice causing significant disruption and dangerous conditions due to extremely strong winds on Friday.
‘Flying debris resulting in danger to life.’
It has also advised residents to avoid the seafront in the coming hours.
A statement on Facebook reads: ‘The arrival of Storm Eunice is expected to bring strong winds - we could see large waves at the coast.
‘Avoid the seafront during the storm, secure garden furniture, bring your bins in as soon as you can and don't leave loose waste out.
‘The flood gates will be closed in Old Portsmouth and the Seafront Road gates will be closed, and as you can see below the Southsea Coastal Scheme team have been hard at work installing temporary rock and shingle defences too.
‘There is likely to be disruption to transport, especially ferries and hovercraft, so please check with travel operators before setting off.’