Dennis’ Tidbits 


August 20, 2019

Weather still not an exact science 

Dennis 5At this time, the Western Pacific Tropics are on steroids with multiple typhoons having their way with the Philippines, Taiwan, and many parts of Asia, yet the Central and Eastern Pacific and the Atlantic are dormant and have been for quite some time now. There are a couple areas of disturbed weather here and there but that’s about it. Normally August is a very active month for tropical development and intensification, but thunderstorm clusters aren’t well-defined large areas of convective activity, the main players in the birth of such systems.

Right now the tropics are under the influence of a neutral zone with no sign of either El Niño or La Niña present. We’re sort of in between events so anything can happen. Historically the neutral zone sees more normal activity in both oceans but that is not always the case – like so far this August. Both oceans are acting erratically. Our last neutral zone occurred in 2013 and 2014, and it was a fairly normal season in the Tropical Convergence Zone. The much-hyped mega El Niño of 2015-16 behaved erratically for the first time anyone can remember over much of the globe. 

Things went kind of neutral in 2017 before another mild El Niño ran the show in late 2018 and early 2019. The most recent El Niño event pretty much followed the script here in the Pacific but did a total flip-flop in the Atlantic. The 2018 season in the Atlantic more resembled a strong La Niña event when tropical activity really ramps up with more and much stronger hurricanes. 

Florence and Michael were proof of that, both reaching Category 5 status at one point of their existence. Florence stalled out for days in the Carolinas dropping up to four feet of rain in just one week, about as much as we get in three and a half years locally! Then Michael appeared, and he became the first Category 5 hurricane to make landfall in the Florida Panhandle in a place called Mexico Beach. Michael was the first Category 5 storm to make landfall in the U.S. since Andrew in August of 1992. The classic 2005 season was in the midst of a strong La Niña and look what happened. They ran out the alphabet and had to go six deep in the Greek alphabet that year. That was the year Katrina made shambles of New Orleans and the Mississippi coast.

Generally, Tropical Pacific waters are much warmer during El Niño events and as a result there are more systems and they tend to be quite a bit stronger. Surrounded by all of that hot water, the atmosphere contains much more moisture. The surface low pressure produces much stronger updrafts with minimal shear wind influence plus they have all of that hot water to work with which resulted in a greater number of major hurricanes that season. On one occasion, the Eastern Pacific ran out the alphabet and that was in 1992 with a fairly potent El Niño going on that year. However, the Atlantic was totally opposite with not one named system until the last third part of August. By that point, there are normally at least a half a dozen storms already in the books.

At this time, it’s a sketchy prognosis about if and when we will see La Niña conditions, but it seems to be headed in that direction. The waters off Southern California are quite a bit cooler this summer than the balmy readings we saw most of last summer. The waters SW of Baja are significantly down compared to a year ago this time, which shortens the life span of any spinners that move past the tip. 

For a long time now, probably 50 years or better, we thought we had the patterns pegged as far as La Niñas and El Niños until the two latest events that tricked everybody at the NOAA. That’s what’s interesting about the weather. It’s still an inexact science. Always a surprise. Modern technology has certainly put us closer to getting it right but just when we think we’ve figured it out, it has a new surprise, and it probably will for a long time to come.

The waters in the Gulf of Mexico are really warm, as high as 88 degrees in some spots and that hot water is a developing storm’s best friend. 

Like I said before, the Atlantic switch will turn on eventually and that happens fast. 

See you all Friday, ALOHA!