Probability of dry summer for Wairarapa
New Zealand is currently experiencing an El Nio weather pattern which is predicted to continue through to the end of summer. In Wairarapa El Nio conditions generally lead to low rainfall due to predominant west to southwest airflows. This in turn could lead to a dry summer.
Greater Wellington environmental scientist Laura Watts says, “A good indicator of whether we are in an El Nio, La Nia, or neutral phase is the Southern Oscillation Index (SOI). The Index showed sustained negative values over spring, which shows that we are in an El Nio weather pattern.”
Ms Watts says that the El Nio pattern is most likely to cause drier than normal conditions in the eastern Wairarapa hills and around Martinborough.
“In these areas the chances of low rainfall are twice, or even possibly three times, more likely compared to non-El Nio years. This means that a 1-in-10 year dry summer has a 1-in-5 chance of occurring in the eastern Wairarapa hills this summer.”
See information on rainfall, river flows, and soil moisture from Greater Wellington’s monitoring sites in Wairarapa.