Specialists say long periods without sunlight can cause long-lasting mental health issues, such feelings of helplessness, fear and fatalism.
Since the beginning of July, Auckland has only had two days without rain, and psychologists say the constant wet weather could be taking a toll on people's wellbeing.
MetService said between 15 June and 5 July, Tāmaki Makaurau saw 20 straight days of rain, and more is expected this winter.
Meteorologist Andrew James said the volume of rainfall was unusual, and people should brace for more rain.
"Under La Niña it is typical for the northeast of the North Island to be wetter than average, but this year hasn't been typical. Records have been broken across the North Island."
A study published in the Journal of Psychiatric Research found experiencing severe weather events can lead to problems such as depression, anxiety, suicide thoughts, substance abuse and loss of identity.
In some cases, the lack of sunshine could cause long-lasting feelings of helplessness, fear and fatalism.
Psychology professor at the University of Otago, Richard Porter, said sunlight was paramount for one's wellbeing.
"An important thing in maintaining mental health is our circadian rhythm and the main thing that tunes in the circadian rhythm is light. So, it's problematic for our mental health when we don't get that light."
Climate Psychology Taskforce
In 2014, the New Zealand Psychological Society created a Climate Psychology Taskforce - CPTF.
One of its goals was to help practitioners address any post-traumatic stress that extreme weather and displacement could cause to patients.
Since its creation, the CPTF has promoted "climate psychology" through professional education including symposiums, seminars and workshops.
Taskforce co-convener and psychologist Brian Dixon said the force was created to recognise climate effects on mental health.
"There is a huge need within our professions to learn more. Our taskforce has spent quite a bit of energy training people, so every seminar or conference that we go to, we try to present a workshop to educate people on climate psychology.
"We are two professional groups helping with training in this area - the Psychological Society and the College of Clinical Psychology."
Dixon said practitioners needed more funding to be able to upskill.
"One of the things we realised is how under-resourced people are to be taking action. There has been money made available, but it needs to get out of government departments and ministries, into where it is needed.
'If you can, embrace it' - psychologist
Clinical psychologist Dougal Sutherland advised those who can, to think about how to make the best of a damp situation.
"You make the most of things like open fires, or sitting and watching Netflix, catch up on reading that you always wanted to do, or maybe have friends over for a long movie marathon.
"It's about accepting that at times we won't be able to control the other, but we might be able to choose how to respond to it."
RNZ
