He said she had "some health issues", but would not elaborate. Nor would he comment on whether she had suffered from depression.
The last confirmed sighing of Ryall was about 9am Friday, when she was seen walking near the intersection of Derby and Cobden streets, a few blocks from her Domett Street home.
A private search was launched on Friday, involving family, friends, firefighters and Westport Deep Sea Fishing School personnel. They failed to find her and called police on Saturday night.
Police called in Land Search and Rescue (LandSar) Sunday morning.
Ryall is described as 160cm (five foot, three inches) tall, of solid build, with short, wavy, red/brown hair.
She was believed to be wearing three-quarter black leggings, possibly a short-sleeved top, and green black-soled leather pumps, and carrying a black handbag.
She is assistant manager of Westport's St John Community Shop and has two adult children.
Watson said searchers had looked everywhere they thought she might be, but found nothing. Police suspended the search last night while they sought more information.
They said they believed Ryall was still in the Westport area but were not ruling out the possibility that she might have travelled further afield.
They were seeking any confirmed sightings since 9am Friday.
"We'd also request that local residents check their own properties, sheds, unlocked buildings, just in case she has gone into a property and might be hiding up."
Mr Watson said police hadn't called in LandSar until yesterday because LandSar didn't usually get involved in missing person cases.
"Someone who's missing, they've made that decision to take off, so to speak, whereas a lost person is totally different; they want to be found."
Buller LandSar chairman Ross Cocker said police called them just before 9.30am yesterday. By then the private search had already covered a big area, mainly in the north end of Westport.
"They'd been to places that were familiar to her. She grew up in Larsens Hotel. I know the hotel [a vacant building] had been searched three times."
Searchers also combed Buller High School, Patterson Park racecourse, the floating basin, the speedway and the Shingle and North beaches, Cocker said.
Further south they had searched Percy's Bush and the Westport Domain.
A kayaker paddled the floating basin and as far up the Buller River as the Esplanade and a drone flew over a wide area.
Last night LandSar received an unconfirmed report of a woman fitting Ryall's description at North Beach and LandSar volunteers went back out to search in the dark. Three cars, plus four searchers on foot with spotlights, searched until 10.30pm, but found nothing.
All up the search had involved about 10 firefighters, 20 fishing school personnel and 20 LandSar volunteers, as well as friends and family, Cocker said.
A Facebook message yesterday resulted in another 29 people turning up to help with the search. Cocker said he thanked them, but told them they weren't needed.
LandSar had stood down today while police followed up leads.
"I realise she's three days missing but we still don't know where to look."
- Westport News
