2016 Eastern Pacific Hurricane Outlook

In just a few weeks the forecasters at the University of Colorado will publish their long term Tropical cyclone outlook for the Atlantic season, along with a footnote mention for the Eastern Pacific. The prognostications are based on statistics, complicated fluid models, long term predictions and experience based hunches. Since Eastern Pacific tropical cyclones don’t make landfall in the United States the vast resources of NASA, NOAA, and academic study are focused on the Atlantic storm season. 

These early predictions are based on the conditions in late February and what they are predicted to lead to four to eight months later. However, as any weather watcher will note, the environmental state of the planet is making a 10-day forecast seem like looking into eternity. 

In recent years, even Dr Gray’s seasonal Atlantic forecast has significantly missed the mark. Long range forecasts just look at the probability of storm formation in a season, knowing where they might affect is still a tough call, even on active systems just days away from landfall. If any of us was able to make accurate long range predictions of landfall insurance and shipping companies would make that person incredibly wealthy. 

Short term track forecasts in the Eastern Pacific have become increasingly more accurate. In 2015, the National Hurricane Center narrowed the margin of error by about 25 miles per day. But as any storm forecaster will affirm, a forecaster that is right 70% of the time is a god. For those who dispute that, you just need to look at the track forecasts issued by the NHC, the breadth of the cone represents an average 15% variation let and right of the projected track, or about a 30% margin of error. 

This is my twelfth Eastern Pacific seasonal forecast which focuses on the Baja California peninsula, and since it is the portion that is most commonly affected, Baja California Sur. In that time period, my long range hunches have proven out, including the prediction of a significant landfall in 2014, Hurricane Odile. 

Last year I did not author a spring prognostication, as I was in the process of re-engineering the BajaInsider. The conditions in the Eastern Pacific indicated an active year, but I was stunned by the earliest tropical cyclone to ever make landfall on the peninsula in early June, more than 70 days earlier than the previous record holder.

Tropical Storm Blanca made a passing landfall near Magdelena Bay on June 8th and again made landfall as a Tropical Depression near San Ignacio on the 9th. But Blanca only delivered limited rainfall and winds just over tropical storm intensity at its peak, affecting some of the least populated regions of the peninsula. As our average Baja tropical cyclone landfalls go, Blanca was a non-event. 

In September in an equally unusual event, we saw Tropical Depression 16E formed just west of Magdalena Bay and made landfall near San Ignacio, but it too was a relative non-event with winds to 28kts and limited rainfall. But thankfully, as we worked our way through the first weeks of October no other systems threatened the peninsula. The peak threat period to the peninsula has traditionally been August 15 to October 15, with the latest landfall of a tropical cyclone being October 17.

But the strange weather patterns in 2015 weren’t finished with the peninsula on schedule. Although it did not make landfall, Sandra, once a Category 4 cyclone well to the south of the peninsula, met its demise just about 100 miles south of Cabo San Lucas, just two days before the end of the alleged Eastern Pacific season on November 28th. This made 2015 the longest hurricane season for Baja, stretching almost the entire length of the Eastern Pacific season which runs May 15 to November 30. 

The 2015 season was also more active than a normal year, with 18 named systems, with a 65 year average of just over 14 named storms per year. But the El Nino event of 2015 was the most significant in Zones 3 & 4, further out into the Pacific. Thus many of the tropical cyclones of 2015 formed too far to the west to be of a threat to the peninsula or even mainland Mexico. 

The year also saw one of the most powerful storms ever to form anywhere, and the strongest ever in the Eastern Pacific, Category 5 Hurricane Patricia. Patricia made landfall on the mainland just north of Puerto Vallarta and surprised everyone with a limited amount of destruction. This is attributed to just plain lucky, as the system made landfall in a more sparsely populated region with the most dramatic geographic elevation rise leaving the coast. Had the system hit 50 miles north or south the results could have been much more devastating. It was also a testament to the excellent performance of Mexico’s emergency services. 

The Madden-Julian Oscillation

The MJO is an even more recent discovery affecting tropical cyclones than is the El Nino event (or ENSO for El Nino Southern Oscillation.) Discovered in 1971 it initiates in the Indian Ocean and travels east, usually just to the north of the Inter-Tropical Convergence Zone. (ITCZ) Last year’s early season Hurricane Blanca was a result of a particularly strong MJO tracking particularly far to the north. 

In simplest terms the MJO is a rolling phase of cloudy/wet and dry/clear. During the dry/clear phase, the sun warms the ocean and causes high evaporative levels, drawing moisture into the atmosphere. With all that moisture it eventually gets cloudy and that precipitation falls out, causing a wet phase. The effects of the MJO are minimized in Eastern Pacific when we have an El Nino event. When that wet cycle reaches our hurricane basin we have an increased probability of a tropical cyclone.

Tropical Waves

Tropical Waves are often referred to as the seeds of tropical cyclones and are high convention super energy charged disturbed air, moving west from the Sahara desert. They begin to form sometime in late May and continue to move west along the Inter-Tropical Convergence zone through late October. As a note, tropical cyclones can also form without tropical waves, but that is less common. 

In the early season, much of their energy is dissipated by interaction with the northern coast of South America. As the relative angle of the earth changes in reference to the sun they move further north and by mid-August, their path puts them into our Hurricane Birthing Zone, off the southern coast of Mexico. They tend to form 3 to 7 days apart and take 10 to 14 days to travel from Africa to our side of the planet. Sometimes their energy is used up forming storms in the Atlantic, this is why very often when the Atlantic is busy the Pacific is quiet and visa versa. 

When Tropical Waves and the MJO Hook Up

Unfortunately, for the Eastern Pacific the point where the fading MJO moving east and the diminishing tropical waves moving west meet with the greatest remaining energy is the East Eastern Pacific. I have been tracking these events for 5 years now, and when a peak wet MJO cycle hosts a moderate to strong westbound tropical wave probability of a tropical cyclone formation in the Eastern Pacific is greater than 80%. (I’m still working out a few statistical anomalies on this one) 

How the ENSO Affects Tropical Cyclones

The El Nino Cycle is perhaps one of the most profound sea temperature fluctuations in the world and has an impact on weather across the northern hemisphere. This year, 2016 will be known as one of the most dramatic El Nino, or warmer than normal events yet recorded. But the part of 2016 that will affect the Eastern Pacific tropical cyclone season is now forecast to be a neutral year. The statistics in this article are based on the ENSO state in our hurricane from August to October, which may differ from the overall state or title given to a specific year in a simple chart.

Tropical Cyclones are nature’s engine for dispursing energy away from the equator. The warmer the water the more potential energy is stored up to feed tropical cyclones. The warmer water also changes and strengthens wind currents that drive the systems, or even destroys them since hurricanes are actually very delicate, not liking any strong winds other than their own. This is why it is commonly believed that there are fewer Atlantic storms in El Nino years. 

I have often also heard it said that El Nino brings more tropical cyclones to the Eastern Pacific. My database goes back to 1950 there have been almost an identical number of El Nino (22), La Nina (21) and Neutral (22) years during the season in the Pacific. Much to my own amazement, it is not true that more storms form in the Eastern Pacific in El Nino years. With a total of 929 named systems since 1950, I found 14.59 storms form in El Nino years, La Nina years are the quietest, with an average of 12.33 storms and Neutral years are the busiest with 14.90 storms.

In the last 65 years, 62 named systems have made landfall in Baja, almost all of them in Baja California Sur. La Nina years are the safest, with only an 85% probability, El Nino years are second with a 90% chance, leaving Neutral years the leader with a 109.1% chance of a named system landfall. (Meaning more than one storm can be expected in a neutral year.) This year is currently forecast to be in a neutral phase during the hurricane season. 

Now there has to be a footnote here. As any statistician will tell you 65 years and 929 hurricanes is a pretty shallow database. This is further complicated by the quality of that information as prior to 1984 there was no full-time satellite coverage of the Eastern Pacific and some hurricane were only “discovered” by ship reports and shore stations well into their maturity and some may have been missed entirely at the early end of my data. I also excluded ‘near misses’ like Category 4 Hurricane Lisa which roared up the middle of the Sea of Cortez, making landfall on the mainland, but caused a dam to rupture in La Paz, killing several thousand and making it Baja’s deadliest storm. With another two dozen near misses dating back to the 1950’s, it is just too difficult to assess as to what threat they posed.

More below…

Sea Surface Temperatures

The warmer the water the more energy is available to feed a tropical cyclone. Tropical cyclones require sea surface temperatures greater than 26°C to live, below that they begin to dissipate. Although SST’s vary through the year the general trend on the eastern side if the Pacific from Alaska to the equator is warming up, most climatologists blame this on the dramatic increase in the use of soft coal in the orient and is only superfluously related to El Nino. 

Although Asian soft coal is environmentally more offensive than the harder anthracite coal found in the eastern US, both produce environmental results that the world needs to move away from even faster than that of petroleum products. In addition, to the carbon dioxide contaminates, particulate emissions from coal add to the blanket trapping heat in our atmosphere. Diesel fuels are next greatest offender on the list for particulate emissions. 

After Hurricane Katrina’s landfall on the southern coast of the US climatologists discovered it is deep warm water that generates Major Hurricanes like our 2014 Hurricane Odile. In 65 years only two other Major Hurricanes (Category 3 or greater) have made landfall in Baja with Odile being the first Cat 4. The over temperature waters surrounding the peninsula have persisted for the last 7 years, slowly increasing the depth of that warm water between Cabo San Lucas and the Socorro Islands and giving us an increased chance of Major Hurricane landfalls along the southernmost portions of the state. 

The final statistical look is at the intensity of our tropical cyclones. We need tropical cyclones in Baja California Sur, they are as a whole, what replenishes the southern peninsula and often provide a bulk of the seasonal rainfall. Those new to the peninsula have reason to be gun shy, Odile was a monster storm and once you break into the Category 3 and better you are looking at an entirely new level of potential destruction. But Odile was a rarity, the average intensity of tropical cyclone landfalls in Baja California Sur over the last decade is only Category 1.3 and the state usually recovers quickly, unlike places like New Jersey and Houston. (for those of you who have weathered fewer than my dozen or more tropical cyclones as a sailor, I do mean “only”)

My Hurricane Outlook for 2016

If you are planning to vacation in Baja California Sur this summer through early fall be aware the threat reaches its peak the third week of September. If you are a part-time property or boat owner in the southern state make sure your investments are secure before leaving and someone will be available to attend to last minute preparations and salvage in the event of a Baja landfall. 

As stated above in this article my long range prediction is a ‘for what it is worth’ between the environmental conditions discussed here and my favorite Ouija board, and over the last decade or so I’ve done pretty well. In many ways, the conditions over the last several years have developed so far out of the norm that statistics and previous experience may be irrelevant.

I’m afraid my outlook is grim, as I go way out on a limb to predict the landfall of three named systems on the peninsula in 2016. With the ocean warming far faster than normal this year the first will be a tropical storm landfall will come before the normal season. I then expect two more named systems to make landfall on the peninsula this year during the regular season between mid-August and now extending into late October. Taking a real long stretch, I’ll give even odds on one of them being a Major Hurricane, because that water south and west of the peninsula has remained well above normal all winter and is now not only warm, but warm several meters down. This provides the fuel for a Major Hurricane that we had not seen in previous years. So be ready to batten down the hatches. 

Follow Your Tropical Weather Here

As for the last 13 years we will provide storm coverage for each system in the Eastern Pacific with the NHC forecast, special BajaInsider custom graphics an information on storm preparation. As the season progresses we will update the general threat level in the Eastern Pacific with our Hurricane Watch Reports and additional detailed information on the developing factors that form tropical cyclones Sign up for our Insider Updates to receive not only information on the latest stories but tropical weather alerts direct to your email box when tropical weather threatens the peninsula.

But what do I know… Enjoy your day!