A clothes line index is being considered by the MetService to make weather predictions more user-friendly.
As well as providing the usual predictions about temperatures, rain and wind, the MetService website already advises people on how many layers of clothing to wear, to suit the conditions.
Now it is considering going a step further and introducing a section that will forecast the best days to hang out washing.
"Bringing in a clothes line index is certainly something that has been recently discussed," MetService spokesman Daniel Corbett said.
"If we are already predicting how many layers of clothes people should be wearing or what surf conditions are like, it isn't such a silly idea to forecast if it is going to be nice enough to hang out the laundry.
"It is by no means definite that this will be introduced any time soon, but anything we can come up with that helps people have a better practical understanding of what weather forecasts mean for them has to be a good thing.
"A clothes line index would take in factors like humidity, sunshine and wind conditions. As well as being fun, I think it would be quite popular."
However, Corbett said he doubted the MetService here would go as far as some weather forecasting services in the United States do.
"I've even seen a weather index in America that tells people if it might be a good day to wash the car or not," he added.
Persil laundry powder brand manager Georgina Allen said a clothes line index would make New Zealanders' lives much easier.
"With 77 per cent of Kiwis drying their washing outside in the sun and 65 per cent washing more than three times a week, it would be a very handy tool to help them pick which days to do the laundry."
New Zealand's best known clothes line supplier, Hills, cautiously welcomed the washing line forecast idea.
"It is a novel concept, but predicting a good time to hang out wet clothes to dry could easily go pear-shaped," a Hills spokesperson said. "Get that one wrong and there could be a lot of pretty angry people out there.
"It would be a bit like following earthquake predictions by someone like Ken Ring. Some folk would swear by it, while others simply wouldn't give it the time of day."