Forecasts specifically for Turoa and Whakapapa ski fields will be produced by MetService.
Previous forecasts have covered Tongariro National Park, lumping together the two ski fields and wider mountains area.
MetService will work with Ruapehu Alpine Lifts (RAL) to improve the accuracy of the forecasts in the national park and on New Zealand's two largest ski fields.
Different areas of the park, and the two ski fields, can have different weather.
Forecasts will now be generated using a mix of computer generated and manual forecaster assessment, increasing the accuracy.
RAL chief executive Dave Mazey says the variations in weather experienced on Mt Ruapehu, and even between the two ski fields, can be significant.
"We see a direct correlation between the forecast and visitor numbers, so being able to provide a forecast that is as accurate as possible means we can keep our visitors better informed.
"We're always looking for ways to improve our service and believe this is a great step forward.
"Site-specific information will also enable RAL to make better operational decisions. It will help facilitate roster changes to ensure our customer service levels on busy days can better meet demand.
"It will also enable us to apply the most appropriate resources to avalanche control and the de-icing of lifts following storm cycles which should assist with facilities being open sooner after the weather clears."
Site-specific forecasts for both Turoa and Whakapapa ski fields are now live at http://www.metservice.com/skifields/turoa and http://www.metservice.com/skifields/whakapapa.