The RNLI is urging people to take extra care around Cornwall's coastline as Storm Austen is expected to bring winds of up to 70mph on Friday.
The Met Office has upgraded its weather warning from yellow to amber, with strong winds and heavy rain forecast across the region.
The lifesaving charity is warning that conditions along exposed coastlines, cliffs and seafronts could become particularly dangerous, and is encouraging people to exercise extreme caution if visiting the shoreline.
Some RNLI lifeguarded beaches across the South West will remain operational during half term, although conditions may be extremely challenging. Lifeguards may choose to fly red warning flags if conditions are deemed too dangerous for entering the water.
Beaches without lifeguard cover are expected to be especially hazardous during the storm, and visitors are being urged to stay well back from the water's edge.
RNLI Water Safety Manager Ross Macleod said: "Storm Austen is set to bring potentially dangerous conditions, so we're asking the public to stay vigilant and not take unnecessary risks.
"If you plan to visit the coast or any waterside location, we urge you to stay a safe distance from the water, as conditions could knock you off your feet or wash you into the sea.
"If you find yourself in trouble in the water, remember Float to Live. Lie back in the water with your head tilted back so your ears are submerged, extend your arms and legs and try to relax until you regain control of your breathing before calling for help or swimming to safety."

The RNLI is also advising anyone who sees somebody in difficulty in the water not to enter the sea themselves.
Instead, people should remember the charity's "Phone, Float, Throw" advice.
Ross added: "Phone 999 or 112 and ask for the Coastguard, tell the struggling person to float, and throw them something buoyant, such as a lifebuoy or life ring."
Safety advice: Float to Live
- Tilt your head back with your ears submerged
- Relax and try to breathe normally
- Move your hands and legs to help you stay afloat
- It's OK if your legs sink, everybody floats differently
- Once your breathing is under control, call for help or swim to safety
If you see someone in trouble at the coast: Phone, Float, Throw
- Phone 999 or 112 and ask for the Coastguard
- Tell the person to Float to Live
- Throw them something that floats, such as a life ring
More Storm Austen News:
- Storm Austen: Cornwall train services reduced under amber weather warning
- Storm Austen: Residents urged to prepare for possible power cuts in Cornwall
- Storm Austen: Met Office upgrades Cornwall weather warning amid fears of disruption

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