After a three year dip in the La Nina pond, the cooling Pacific waters are warming back up. That means sayonara to La Nina which has brought in a fairly dry period for us. Dry air is easier to heat up and easier to cool down and without doubt we’ve seen extremes in both ends. Just look at the record heat from last May, June and July and then cold of last December and February two years ago. Here is the latest sea surface temperature anomaly and it’s easy to see the warmer (red) water along the South American coast. I circled it for good measure:
So does this mean those waters will go to a ‘neutral’ phase or a warmer El Nino phase? Right now, we can only look at the models and, perhaps, a bit of history. In 75 years, we’ve never gone more than four years without an El Nino and we haven’t had one in four years, so by that logic of slicing a very small time in history, we would say Yes, an El Nino is coming.
So far there is model disagreement and strength, but the consensus line which I’ve highlighted below suggests that at the very least a weak El Nino will form by the end of summer:
Shown another way by the National Oceanic and Atmospheric Administration (NOAA), the likelihood is certainly positive. You can see the red line, indicating El Nino, is higher beginning in July and continues growing into the fall:
So best guess is that, yes, we’ll be back with warmer than normal Pacific waters this summer. Why is that important? On the upside, warmer water means warmer air which creates strong winds which travel across Central America into the Caribbean and tend to disrupt tropical storms that are forming. So El Nino has a positive impact for us. On the other hand, those winds can transport more moisture which can produce significant flooding (not just here, but across the world).
For more on saying adios to La Nina and the possible impacts, check out this Earthsky article.
I’ll be out for spring break starting tomorrow. Have a safe night tonight and going forward. Don’t let the rain or the cold this weekend blog you down!!
Frank
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