Weather

Are we actually heading into La Nina?

Written by Jane Bunn - Jane's Weather | Aug 23, 2024 4:29:46 AM

As we look ahead to what’s likely to affect us in spring a lot of eyes will be focused on whether the Pacific Ocean continues to transform into La Nina, or remain in a wishy-washy neutral zone. The latest modelling from the USA shows us that wishy-washy may win the day.

This new modelling is a considerable change from the forecasts issued in early August. 

Instead of a 66% chance of La Nina by late spring and a 74% chance in summer, this new modelling keeps it just under 50%.

Now ‘Neutral’ and La Nina are neck and neck in the forecast race.

The latest Pacific Ocean forecasts from iri.columbia.edu

The overall forecast, from the USA and all forecasting institutions, shows that three out of seven models like La Nina by mid spring, one is borderline, another is close, and two remain firmly in neutral. 

The latest Pacific Ocean forecasts from Jane’s Weather

Looking at the Sea Surface Temperature Anomaly (SSTA - how much warmer or cooler than average the top of the ocean is) shows us that we have a huge area of warmer than average water off the coast of Queensland, that means we have an increase in the amount of moisture ready to feed our weather systems and deliver rain.

The latest SSTA readings from Jane’s Weather

 

The question is, will that moisture source be actively pushed here (La Nina), or will it be a little bit harder to feed into our rain systems (Neutral)? What we do know is that there is no chance of El Nino, which actively pushes the moisture away from us. 

 

For more, don’t miss my weekly video update that takes you through:

  • Rainfall deficits/drought in southeast AUS and shows which parts are likely to see more than 25mm over the next week.

  • Heat is not just building, but here in a big way. Hear my thoughts on what this means for the next week and the months ahead.

  • See how drivers SAM and MJO are impacting our weather and changes in the Indian and Pacific Oceans are contributing to the seasonal outlook.

  • We go through rainfall odds for the next few months from not just BoM, but the European, USA and Canadian models as well.

  • See our new icons in action, and a sneak peak at Hourly Rain chance, as I discuss the weather in the next week for Brisbane, Sydney, Melbourne, Adelaide and Perth and surrounds.

https://youtu.be/jj9ASg23zZo