Window of development opportunity coming up?

It’s still early June and typically this time of the hurricane season means that things are usually quiet. Every once in a while we will get a June tropical storm or hurricane, but it’s not the norm. As most of you know, the season really begins to ramp up from about mid-August on. Usually….

This season might not be usual.

I am seeing the beginnings of signs that may point to a development window opening over the next week to ten days and beyond.

GFS and its ensemble members indicating a more favorable MJO state coming up for portions of the Western Hemisphere over the next couple of weeks

GFS and its ensemble members indicating a more favorable MJO state coming up for portions of the Western Hemisphere over the next couple of weeks

For starters, the Madden-Julian Oscillation or MJO is forecast by the GFS and Euro models to be moving in to the phase that often supports development somewhere within the Atlantic Basin. The MJO phenomenon is easy to think of as a period of fertility in the tropics, when deep convection can form and blossom, not just fizzle out and dissipate. While the MJO helps to enhance development it does not necessarily mean that development is a certainty.

The upcoming signal from the MJO is not especially strong but it is there (forecast to be there anyway) and could lead to better upper level winds over parts of the southeast Pacific and extending in to the western Caribbean and western Gulf. With water temps plenty warm in the region, all we need is a kick and it could lead to development in one basin or the other, maybe both. We will have to just wait and see.

If we look at the GFS operational model at the 850 millibar level which is about 5k feet up, we can see one week out from today that a wind shift or monsoonal trough begins to set up from the southeast Pacific, across Central America and in to the western Caribbean. This would act like a focusing mechanism for the air to come together or converge, probably leading to enhanced convection (thunderstorms) across the region.

GFS model at 168 hrs showing (yellow area) a wind shift and overall troff of low pressure stretched out over a large area, we call this a "monsson trough" and it can lead to development if conditions allow

GFS model at 168 hrs showing (yellow area) a wind shift and overall troughof low pressure stretched out over a large area, we call this a “monsoon trough” and it can lead to development if conditions allow

This large counter-clockwise “gyre” is so spread out that in and of itself it wouldn’t develop. We would need to see if an area of concentrated energy or vorticity breaks off and tries to develop out of this larger area of energy. If so, then a low pressure area could get going either in the Pacific or the western Caribbean – leading to the chance of a tropical depression or storm at some point.

As you can tell, the process is long and complex. I am not going to dwell on it day after day for two weeks but it is something to keep an eye on. At the very least, more rainfall than normal may be setting up for portions of Central America and it may lead to a named storm on one side of Central America or the other. Time will tell.

Then there is this interesting set up taking shape: The ECMWF (Euro) is indicating the possibility of an easterly wave (tropical wave) trying to develop way out in the deep tropics between Africa and the Lesser Antilles. Remember, water temps out this way are running above the long term average. If we do in fact see a strong area of energy emerge from Africa, it could take advantage of the warmer water and more favorable conditions overall  and try to develop some. This would be highly unusual and a significant sign in my opinion that this season could be quite busy. Again, time will tell.

We live in an age when computer guidance and satellite information allows us to see in to the future of weather forecasting better than ever before. These early warning signs are helpful since we should no longer be totally caught off guard. It may not prevent a “Labor Day hurricane of 1935” scenario in which case we saw a TS become a Cat-5 hurricane in a very short amount of time but the advances in technology now allows us to be more aware than ever that a threat from the tropics is looming (or could be looming). My point is, do not be alarmed or worried. There’s no reason for that. Instead, be aware. We were told the season could be busier than average and these are possible signs of that happening. So just take note and pay attention a little more than normal perhaps. Applaud the fact that we have such tools at our disposal and as long as we know how to interpret them, it can be a good thing. After all, with such much at stake along our coastlines (all of us, not just the USA), the more lead-time the better; at least I think so anyway.

I’ll have more on Monday during my video discussion.

M. Sudduth 1:20 pm ET June 9

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Atlantic hurricane season begins today

Here we are again, it’s June 1 and that means it is hurricane season. A lot has been said in recent weeks about what kind of season we may have. While it appears that conditions would support a busy season, it is just too tough to know with much certainty how things will turn out. Even if we have a lot of hurricane activity, there’s no way to know where they will track. It is always best to just stay aware and be ready no matter what.

Since it is hurricane season now, the video discussions will be pretty much every day. I’ll post them here and of course they will be in our app, Hurricane Impact, and on YouTube (search hurricanetrack).

In today’s video I go over the latest on east Pacific tropical storm Beatriz and its effects on Mexico and some potential for it to redevelop somewhere within the Gulf of Mexico early next week. I also break down the latest SST anomalies and a look at recent ENSO thoughts as we begin the season.

M. Sudduth 4:30 PM ET June 1

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TD16 forms in SW Caribbean – forecast to become a hurricane

TD 16 track map from the NHC. Note the slow movement over the next five days and the forecast for the depression to become a hurricane as it approaches Central America.

TD 16 track map from the NHC. Note the slow movement over the next five days and the forecast for the depression to become a hurricane as it approaches Central America.

Hurricane season officially ends on November 30 but before we get to that date, we will have to deal with one more hurricane, or so it appears.

The NHC began issuing advisories on TD16 early this morning. The depression is located in the southwest Caribbean Sea, not far off the coasts of Panama and Costa Rica. Overall the environment is generally favorable with warm water temps and a small region of upper level winds that are conducive for additional strengthening. As such, the depression is forecast to become a tropical storm (name will be ‘Otto’) later today and eventually reach hurricane intensity as the week progresses.

Weak steering currents for the time being will result in a very slow motion of the depression as it meanders over the SW Caribbean. In the longer term, enough mid-level ridging should build in to gradually push the would-be hurricane towards the west and in to Central America. Precisely where landfall occurs remains to be seen but interests in Costa Rica, Panama and Nicaragua should be monitoring this system very closely.

The main hazard will be excessive rain and I cannot emphasize this enough. While the wind speed will gradually increase it is the rain that concerns me the most due to the slow movement. Right now there are no significant impacts being felt on land since the depression is far enough off the coast. However, once it begins to move westward later this week, bands of torrential rain will rotate onshore across southern Central America and the potential for flash floods will increase, especially in any mountainous areas. I will address this issue more once the NHC updates their “hazards impacting land” section of the Public Advisory. For now, residents and visitors to the region should be mindful of this system and be ready for the possibility of life-threatening flooding as the system approaches later this week.

Outside of TD16, the Atlantic Basin is quiet as we would expect for the last third of November. The season turned out to be fairly busy and with soon-to-be Otto on the horizon, the Atlantic will end up over-achieving for the year with activity running a little above the long term norm. I will have a more in-depth discussion of the 2016 season in a blog post scheduled for November 30. For now, we will focus on TD16 and its eventual impact to Central America.

I’ll have more in my video discussion which will be posted later this afternoon.

M. Sudduth 8:15 AM ET Nov 21

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Eleven years since last major hurricane landfall and why it matters

Hurricane Matthew with the eye just off the coast of Florida - Oct 7, 2016

Hurricane Matthew with the eye just off the coast of Florida – Oct 7, 2016

A major hurricane is defined as one that has winds of 115 miles per hour or higher, also known as a category three or higher. The last hurricane to meet that critical standard while making it ashore along the U.S. coastline did so eleven years ago today. We all know the story by now – it was the 21st named storm of the historic 2005 season and its name was Wilma. Nothing matching the wind speed of Wilma has made landfall since. Why is so much made of this seemingly important record?

First of all, historically speaking, major hurricanes cause about 80% of the damage from all hurricanes striking the United States. It stands to reason that the stronger the hurricane, the more damage it will cause. We rank hurricanes based on their wind speed and nothing else. The Saffir-Simpson scale was developed in the early 1970s for the purpose of understanding what a hurricane’s winds were capable of.. Since then, it has undergone unofficial changes that led the public, and the media, to believe that storm surge and air pressure were part of the original intent of the scale. This was wrong and still is today. The categories of hurricanes that we know as being 1-5 have nothing to do with storm surge, pressure or rain fall. As such, the term “major hurricane” refers to a category three or higher hurricane based on wind speed and wind speed alone.

Major hurricane landfalls in the U.S. are rare. We have seen periods of several years go by without any major hurricane landfalls. It takes the right set of atmospheric and oceanic conditions to get a major hurricane to form in the first place let alone allow it to maintain itself all the way to landfall. However, when it does happen, the damage is usually immense in scale.

Some years, like 2004 and 2005, a rash of major hurricanes make landfall. In fact, beginning with Charley on August 13, 2004 and ending with Wilma on October 24, 2005, a total of seven major hurricanes hit the U.S. This is almost (if not more) incredible than the current record of ZERO major hurricanes hitting the U.S. How could the variability be so extreme? Seven in what amounts to really a little over a year’s time to nothing in over eleven years? Most say it’s just dumb luck. In the grand scheme of geologic time, 11 years is nothing. It’s like playing roulette. You can bet red over and over and over and never hit it. Then, for reasons unknown, red comes up seven times in a row. Pure chance. Now, the weather does not work quite like that but luck has in fact been on our side….or has it?

I am not alone in making the argument that the lack of so-called major hurricanes has spared us from disaster. Let’s take a look at the hurricanes that have managed to reach the U.S. since that fateful day eleven years ago:

  1. 2008 – Gustav and Ike – both responsible for tens of billions in damage and numerous deaths
  2. 2011 – Irene – another costly hurricane that affected areas from North Carolina to New York and even parts of New England
  3. 2012 Isaac and Sandy – combined, the two “category one” hurricanes made 2012 one of the costliest and deadliest hurricane seasons in years
  4. 2016 – Hermine and Matthew – again, two low-end hurricanes that wreaked havoc on Florida and the Carolinas with Matthew being one of the deadliest hurricanes in over four years while coming dangerously close to being an absolute catastrophe  for parts of the east-central coast of Florida

What do all of these hurricanes have in common? Water. A majority of the damage and most of the deaths were the result of water – mostly storm surge. In the case of Matthew, it was excessive rain that once again led to historic flooding and loss of life due to people driving vehicles in to flooded areas.

The dollar amount for all of these hurricanes is simply staggering. We’re talking over $100 billion in combined damage, probably more when considering the long-term economic toll on the regions that were impacted. None were “major hurricanes”. Something has to change because what on earth are we going to do when a “real” major hurricane shows up again?

I wrote in a blog post several months back about the lack of hurricane activity being analogous to having a lowered immune system. We know that hurricanes have not become extinct. Matthew was a grim reminder of that fact. So many people say they had no idea of what was coming in terms of the flooding. How can this be? I’ll tell you how. Here’s another stat for you: 17 years. That’s how long it had been since the last “we had no idea the flooding would be this bad” for North Carolina. Floyd in 1999 was the last such event. Floyd was a powerful category 4 at one point with 155 mph winds that forced millions of people to evacuate across the Southeast coast. The hurricane weakened dramatically leading up to landfall and was a category two by the time it reached the NC coast. What was the primary damage and killing agent? Water. Storm surge at the coast and an overland surge of rain water for inland areas. No one would ever forget Floyd – well, not for 17 years at least. I guess 17 years is long enough to forget because, well, you know, people said Matthew took them by surprise. Ugh. Just ugh….

We need to do better. The focus on major hurricanes is out of touch with the reality that too many people now live in harm’s way; and not just along the coast, so that ALL hurricanes, and tropical storms for that matter, should be considered dangerous.

To be fair, I think the media does a great job at conveying the risks. The Weather Channel led the way on a national front when Dr. Steve Lyons first introduced the graphical impact scale showing which hazards posed the most risk for a particular event. Since then, other efforts have been made to alert the public as to what is coming and how to avoid it.

The National Hurricane Center has put in to their public advisories the “Hazards Affecting Land” section. This is the equivalent of spelling it out for everyone in harm’s way – I use it to plan my attack with the equipment that I set up. Why don’t more people know about this?

At the end of the day, people focus on the scale – the scale that was invented by two brilliant people for one purpose and one purpose alone: wind damage potential. With the exception of Andrew in 1992, wind has been the least of our problems. Building codes have helped in the decades since Andrew but nothing is being done on a grand scale to combat the issue water.  We can and must do better with our education and awareness programs.

It is time to focus on the entire package. Hurricanes bring with them four main weapons, not just wind. More attention needs to be placed on storm surge and rain fall. Perhaps a new, modern rating system for tropical storms and hurricanes would help. Might I suggest that we take the hazard with the highest potential for damage and loss of life and use it to rank the hurricane. Example would be Ike. We knew it had a lethal, 20 feet plus storm surge coming with it. That’s a category five in my book. Don’t think so? Look at the damage on Bolivar peninsula and elsewhere. Homes swept clean. Cat-5 which means EVERYBODY LEAVES. As it was, Ike teetered around being a category one and two right up until landfall. So many people I talk to say, “When it reaches a three, I pay attention and plan to leave”. This is not good on so many levels.

As for rain? Same thing. The tools are there to know ahead of time that a tropical cyclone will bring enough rain to a region to cause life-threatening flooding. We already see those very words mentioned in official NWS/NHC products. To this I say give it a rank. If it is life-threatening, it is at least a category three, maybe higher. Assign the ranking based on the single biggest risk factor. In the case of future Katrina and Andrew situations, they are a five no mater what and remain a five until after landfall.

These are just ideas based on my 21 years of seeing it all go down in the field. I have been there and have seen the results in person. So many people tell me that they had no idea it would be so bad and in almost every situation they were talking about a category one or two hurricane.

Wilma was the last major hurricane to hit the USA. Perhaps it can be the last time we refer to a hurricane as being major based on wind speed alone. I applaud the weather community, the media and the NWS/NHC for doing all they can to convey risk. More needs to be done to re-wire the collective thought process so that ALL hurricanes are thought of as potential killers, no matter their ranking.

Something to ponder as we move beyond the eleven year mark since Wilma. Will 2017 give us another chance to get it right? Or at least do way better? I guess we will find out soon enough.

M. Sudduth 9:10 AM ET Oct 24

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