The bad weather will be caused as the killer storm Nock-ten blows in from the Philippines.
Boats are advised to ignore the blue skies and not put to sea. Waves of up to three metres are predicted for waters off Phuket, a spokesperson for the Meteorological Department said from the Phuket centre near Phuket International Airport.
Winds are likely to range from 20 kmh to 35 kmh and may even intensify on Saturday, forecasters predict.
Tropical storm Nock-ten has proved to be devastating in the Philippines, where the death toll is now at 35, with 25 missing.
The afp news agency reports: Although Nock-ten passed into the South China Sea on Thursday morning, it continued to cause major problems after causing a series of deadly landslides and floods across the main island of Luzon this week.
The monsoon season between April and October brings uncertain weather to Phuket and the Andaman but it's relatively rare to have a storm from the Philippines reach Thailand.
While the storm is likely to diminish in severity, Phuket's monsoon season can create dangerous ''microstorms.''
Earlier this week, bad weather forced a scheduled Thai Airways flight from Bangkok to turn back to the capital even though the aircraft had reached Phuket and was set to land.
The weather elsewhere on the island did not appear that bad.
A condition known as ''wind shear'' is blamed with pilot error for an aircraft crash on Phuket in 2007 in which 90 people perished.
A freak storm is said to have capsized a dive boat in 2009, with the loss of seven lives, between Phuket and the Similan islands.
Here's the breakdown on the past five years of Phuket weather so far:
Phuket 2007 Total: 2396mm Rain on 181 days Maximum: May 15, 82.7mm
Phuket 2008 Total: 2174mm Rain on 157 days Maximum: September 5, 91.1mm
Phuket 2009 Total: 2451mm Rain on 188 days Maximum: July 11, 104.9mm
Phuket 2010 Total: 2348mm Rain on 181 days Maximum: June 20, 93.3mm
Phuket Jan-July 2011 Total: 1048mm Rain on 97 days Maximum: March 29, 101.6mm