Extreme La Nina

If you are a technical/chart-watcher type of person you might appreciate this graph and the following NOAA discussion. If this was about a stock or a commodity the financial players would be freaking out. A biblical rate/pace of change:

The most recent (July-August) MEI value shows a continued drop from earlier this year, reaching -1.81, or 0.64 sigma below last month's value, and 2.35 standard deviations below April-May, both record-fast drops for this time of year. In fact, the three-month drop set a new all-time record for any time of year, beating a 2.33 sigma drop in 1998.

The most recent MEI rank (2nd lowest) is clearly below the 10%-tile threshold for strong La Niña MEI rankings for this season. One has to go back to 1955 to find stronger La Niña conditions for this time of year in the MEI record, and back to September-October 1975 for lower MEI values at any time of year.

Conclusion: We have one heck of big La Nina that has formed very quickly. We have not seen conditions like this in 55 years. What might it mean for the US:

-Above-average precipitation in the Pacific Northwest.

-Below-average precipitation in the Southwest and in portions of the middle and lower Mississippi Valley and Tennessee Valley. 

-Increased Atlantic hurricane activity by decreasing the vertical wind shear over the Caribbean Sea.


BK Conclusion: If you are planning on a ski tri this winter avoid Colorado and consider Whistler. Nice weather (drought conditions) will continue in the NE. There is a very high risk of a major storm developing in the Western Caribbean in the next three weeks. Hurricane Karl was a good example. It just knocked Veracruz hard. There were winds as high as 115mph and the storm brought 8 inches of rain in 90 minutes. Eight deaths.

If a storm of this magnitude were to hit the northern GoM it would shut in the oil/gas production for some time. Depending where (if) it makes landfall there could be significant impacts.

La Nina brings warm water to the western Pacific. This will result in big storm after big storm hitting into China/Indonesia. So far there have been 11 typhoons to hit Asia this season. The most recent is Fanapi. It is about to make a mess of southern Taiwan. Then off to China.

Why is this La Nina cycle so strong? I have no clue. Nor do the people who study global weather. There are many records being reached this year. The most significant (to me) is the rapid increase in global ocean temperatures that have occurred. The strength of this ENSO cycle is no doubt related to that phenomenon. This powerful La Nina will continue for at least four more months. It is likely that it will end as quickly as it appeared. That transition will bring us violent storms. I would delay plans for a holiday to coastal China until next year.