Otto small but will bring torrential rain and strong wind to portions of Central America

The biggest hazard from Otto will be the rain which is expected to be more than a foot in some locations.

The biggest hazard from Otto will be the rain which is expected to be more than a foot in some locations. Click to view full size.

It is late in the hurricane season but TS Otto has managed to find a small corner of the Caribbean Sea in which to flourish. Recent reports from the NHC indicate that Otto is nearing hurricane intensity and by looking at satellite images, it won’t be long until that status has been achieved.

Fortunately, Otto is small in size with tropical storm force winds extending only 35 miles out from the center. When it becomes a hurricane, those winds will also be confined to a relatively tiny area near the center thus wind is really not going to be the issue here.

Instead, rain is my big concern. Heavy rain is expected to fall across portions of Nicaragua, Costa Rica and Panama today and lasting through the remainder of the week. The extremely slow movement of Otto will only add to this hazard and for areas of Nicaragua especially, rainfall could be excessive and lead to substantial flooding with great risk to life and property. Obviously interests in the region should be paying close attention to the progress of Otto and be ready to head to safer locations should flooding commence. I am very worried about the amount of rain that could fall with this system and will continue to emphasize that fact throughout this event.

Otto is expected to move slowly westward over the next few days and eventually make landfall somewhere in southern Nicaragua and possibly straddle the border of Costa Rica. This is very far south for a hurricane to be making landfall no matter what time of the hurricane season it it. As such, people are not used to this which makes it even more important for folks to keep up to date with the latest information as Otto progresses.

There is no risk of the storm turning north in to the Gulf of Mexico and even the NW Caribbean Sea due to mid-level high pressure building in across the region, acting like a block and forcing Otto to remain south and move generally westward underneath the high pressure area. It is possible that the remnants survive the passage over Central America and emerge in to the southeast Pacific – if so, we’ll deal with that when the time comes.

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

M. Sudduth 8:50 AM ET Nov 22

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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 РHermine and Matthew Рagain, 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 Рthe 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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Season not over yet

NHC outlook map with hurricane Nicole still churning away in the north Atlantic while we watch an area of disturbed weather near the southeast Bahamas

NHC outlook map with hurricane Nicole still churning away in the north Atlantic while we watch an area of disturbed weather near the southeast Bahamas

Here we are getting close to late October and the Atlantic hurricane season is still going strong. Believe it or not, we still have Nicole on the map and yes, it is still a hurricane. In fact, the surface wind energy is being translated in to the North Atlantic enough so that large swells are radiating out from Nicole are reaching the Caribbean Sea and the East Coast of the U.S. Nicole is likely to remain a hurricane for another day or so before finally encountering water that is cold enough to strip it of its warm-core tropical characteristics.

In the meantime, an area of disturbed weather has developed in the vicinity of the southeast Bahamas and has some potential for further organization over the next few days. Right now, upper level winds are just too strong to allow much to happen but the system will bring periods of showers and occasional gusty winds to portions of the Bahamas as it drifts slowly eastward.

Later in the week, computer models suggest that upper level winds could relax some and allow for slow development of a weak low pressure area somewhere over the southwest Atlantic. Water temps are still warm enough to support development but we’re getting to the time of year when we can expect to see more of a hybrid look to storms like this where the winds are spread out over a larger area instead of the classic tropical storm look. We’ll see what happens but so far, there are no indications that this system would pose a direct threat to the Southeast coast outside of additional swells and rough seas that it may kick up.

Beyond that, the Caribbean and Gulf of Mexico are free and clear of any organized disturbances that bear watching for now. However, there are indications that towards the end of the month and in to early November we may see an enhancement of the Madden-Julian Oscillation or MJO. This is a period of favorable upward motion that allows the air in the upper levels of the atmosphere to spread out or diverge, allowing thunderstorms to blossom underneath. With the very warm western Caribbean waters still waiting to be tapped, it is possible that we will see yet another area of interest pop up sometime beyond the next week to ten days. It is not that uncommon to see late season development in the western Caribbean and with a possible favorable MJO pattern, this year may be slightly more active than we’ve seen as of late once we get in to late month and early November.

I will go over everything in more detail during my video discussion which will be posted later this afternoon.

M. Sudduth 8:40 AM ET Oct 17

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