I’m a weather watcher. I’m also a nature watcher. Sometimes the Venn diagram overlaps those two areas.

I know by my blog stats that my posts here about predicting the weather by observing nature have a perennial popularity, even though they are not usually backed by science and are more of “weather lore.”

Meteorologists, on the other hand, look at things such as the La Niña conditions as very real. She is showing her effects in the Pacific now with cooler than normal sea surface temperatures across most of the eastern and central equatorial Pacific. It started in October and continued into this month.

I suppose it’s not exactly “chaos theory” when it comes to weather patterns, but I find it fascinating that cooler than normal sea surface temperatures far from where I live will affect my local weather. That is a big butterfly flapping its wings on the other side of the world.

Don’t confuse La Niña with its opposite partner El Niño which is officially the “El Niño-Southern Oscillation, or ENSO.  La Niña (Spanish, “the girl”) and El Niño (“the boy”) used to be seen as one thing and was once called El Viejo (“the old man”).

With all the talk about climate change, you often hear about what seem to be very small changes in the temperature of the oceans. But very small changes – a degree or two – have very big effects and La Niña and El Niño disrupt normal patterns of precipitation and atmospheric circulation not only in the Pacific but across the globe. A La Niña often, though not always, follows an El Niño.

During a period of La Niña, the sea surface temperature across the equatorial Eastern Central Pacific Ocean will be lower than normal by 3–5 °C.

It is expected that weak La Niña conditions will continue through the winter until probably February. But what does that mean for North America’s weather?

La Nina map

Cooler than normal sea surface temperatures indicative of La Niña conditions stretch across most of the eastern and central equatorial Pacific. (Source: earth.nullschool.net)

Usually, La Niña means below-average precipitation and above-average temperatures in the southern part of the United States, and colder and wetter conditions across the northern U.S. and Canada. It even affects the Atlantic Hurricane Season.

Though my East Coast has been in a drought, the Pacific Northwest had a very wet October, though that probably can’t be explained by just La Niña.

I hope the colder and wetter than normal prediction for the Paradelle area is wrong, but I’ll add it to what the wooly bears and other winter predictions showed this year and check back in the spring.

 

 

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