Betsi Cadwaladr University Health Board says it hopes the remaining lines will be operation by the end of today.
Today, outpatient appointments will go ahead as planned but patients should be aware that there may be some disruption or delay. Patients trying to ring and book an outpatient appointment at Ysbyty Gwynedd may experience difficulties this morning, however we hope that these lines will be up and running by the end of the day.
Urgent operations are going ahead, however, we have cancelled approximately 20 planned operations and individual patients have been contacted. Arrangements are being made to reschedule these patients as soon as possible.
– Betsi Cadwaladr University Health Board spokesperson
Managers at Ysbyty Gwynedd in Bangor have said that staff at the hospital have been working "extremely hard" to ensure patient care continues after phone lines were knocked out following heavy rain and lighting.
Lines are still down following yesterday's storms and are calls are being transferred to staff at Ysbyty Glan Clwyd near Rhyl. It's unknown when lines are expected to be working again.
"We have been working...to resolve the problem and work is continuing with staff andcontractors on site...Staff are working extremely hard to keep all services safe and operational with the support of radios, pagers, mobiles and other specialist phones." - Betsi Cadwaladr spokesperson