Archive for the ‘Tropical activity in the Caribbean’ Category
This is the 4 pm EDT advisory for August 30, 2012.
Two left clicks on the image will enlarge it fully.
By the time you see this posting, the forecast graphic for what remains of Isaac (above) will probably be obsolete. Here is where to go to get a comparable update (however, the advisory above might be the last):
In spite of modern technology the tasks of the National Hurricane Center’s forecasters are not easy and I guarantee they burned the midnight oil as this event unfolded. They have so many variables and unknowns to deal with. I think they do a wonderful job.
Where I live, in west-central Florida about 18 miles inland from where the tiny Crystal River flows into the Gulf of Mexico, there are long-term concerns about our fresh water supply. So I had hoped that Isaac would provide just the right amount of water WITHOUT damaging and costly winds and flooding. Like most humans, I want all of the good but none of the bad that can come from Nature’s wonders. At this time, Thursday evening, 8-30-2012, we are still getting some rain directly related to Isaac even though its center is about to move into Arkansas. Hopefully the system will provide needed rain to drought stricken areas in it’s predicted path. My retired-farmer uncle in Indiana indicates that it’s probably too late for the field corn but could be helpful to the soybeans. As I write, flooding and potential flooding in certain areas of Louisiana are creating real headaches there. There are some places claiming to have more water than with Katrina, albeit for different sets of circumstances.
There is so much information available today and I understand the great value of our acquired knowledge about tropical weather since I first began studying it formally (over 50 years ago) but sometimes, I confess, I think fondly of the days when we had little notion of what was going on until much later in a tropical cyclone’s life cycle. Now, it seems that the media devotes an inordinate amount of time telling us about the negatives and potential negatives that are going on all over the world and I can no longer bask in my ignorance as I used to because I haven’t the will-power or inclination to ignore the resources that are available. But, I concede, there are limits to the notion that ignorance is bliss.
I wish you peace, good health, and happiness.
Since I began this site on August 24 2008, it’s been averaging about 12 “hits” per hour. So, I’m not setting the Internet world on fire. I’m sure that many of my “followers” are either friends and neighbors, family, or former students. Of course a number of people reach this site as a consequence of a search term that blends with something I’ve discussed.
This is my first posting in over three months. That might be strange for a site devoted mostly to tropical meteorology but those who know me understand that I devote most of my tropical weather attention to those systems that cause alarm to folks in Central Florida where I now reside.
The six month long official hurricane season whose last day was November 30 was an active one but not for Central Florida. There were some storms in the Atlantic, Caribbean, and Gulf that caused concern but, if you have been following this site you have no doubt noticed that I ignored most of them. I choose to refrain from alarming anyone unnecessarily when I deduce that a storm in question is not likely to bother us. On the other hand, the National Weather Service errs on the side of caution and consequently the “coverage” was vigorous and reports were easily obtained through the media. Though I think that the media does a good job, generally speaking, I am inclined to suspect that they are spectacularizing their reports. There were times when it appeared that a storm would be coming our way here in West-Central Florida but my information and gut-level feelings indicated a very low probability. SPECIAL NOTE: It appears that in using “spectacularizing” I’ve used a word whose acceptance is debatable; it appears to be a mere colloquialism but that fits me well.
This year’s hurricane season was very active! An average northern hemisphere Atlantic/Caribbean/Gulf of Mexico season has 11 named storms, 6 hurricanes, and 2 intense hurricanes.
For the 2011 season there were 19 named storms, 7 hurricanes, and 3 intense hurricanes.
But for the U.S.A. specifically – the season was unusually timid. In his summary of the season, Dr. Jeff Masters (one of my important sources) wrote: “Only two named storms made landfall, Tropical Storm Lee, which hit Louisiana with 60 mph winds, and Hurricane Irene, which hit North Carolina on August 27 with 85 mph winds, and made two additional landfalls in New Jersey and New York the next day.” By the time tropical storm Don reached Texas it had weakened to a tropical depression. There seems to be general agreement that favorable steering currents were the principle reason for our good fortune in the U.S.
I made no entries concerning Irene, in spite of the scare in New York because we were being flooded with media information and for those with cable or satellite, the Weather Channel was right on top of things. Since it wasn’t threatening our Central Florida region I held back in the wake of such comprehensive coverage.
The way our season luckily turned out has indeed caused me some considerable concern over the tendency that we humans have toward complacency. In the 6+ years I’ve lived in Citrus County, Florida there have been no tropical systems of any severe nature but the year before I arrived, 2004, was a busy one with Jeanne, Ivan, Frances, and Charlie. None of those named storms were strong enough to create a county-wide wake-up call. Some people were without power for a few days but the storms did not create events comparable to those which reverberate in our heads for years to follow – like Andrew, for example, which destroyed my home (in Homestead, Florida) in 1992.
I have heard tales of real estate agents in the area boasting that Citrus County possesses some sort of special immunity for whatever reason. I refute that notion absolutely. There is nothing about the environment that affords it the luxury of special protection other than the high sand ridges that minimize storm surge potential for those who live far enough inland from the Gulf. For example, my house sits at an elevation of 55′ above mean sea level so I don’t anticipate storm surge events. However, high water from heavy rains is a distinct possibility.
In any event I urge you who live in my area to NOT ignore the fact that you live in hurricane country. There are so many things about hurricanes that should not be discounted. For example, doubling the wind velocity actually quadruples it’s potential force. So a 60 mph wind has four times the ability to do harm compared to a 30 mph wind. Here is a link to a site which I put together regarding “hurricane misconceptions.” http://ztechzone.net/learningzone/science/science55/hurricanes.html
Coming next: My Christmas Greeting and Reflections.
When the European Center for Medium-Range Weather Forecast model is running, here is my favorite site for viewing:
For a lot of different reasons, but mainly because I enjoy the insights of Dr. Jeff Masters in his weather blog, I use WeatherUnderground.com. For future reference, a link to his blog is under the Blogroll category at the right margin of this page. In fact, it’s the first listed.
For the ECMWF Model Run, click on the following link and then follow my instructions exactly: NOTE: YOU MIGHT WANT TO COPY THE INSTRUCTIONS BECAUSE ONCE YOU CLICK ON THE LINK THIS PAGE WILL BE GONE UNLESS YOU CLICK BACK –
- At the upper left of the image, click on the “continent” tab.
- Scroll down the menu on the right margin and click in the box labeled “model data”.
- Another menu dropped down. Click on the “model” arrow and select ECMWF.
- Make sure the “map type” remains on MSL which stands for “mean sea level.”
- Click on the “forecast” arrow and wait patiently for the load.
- After it has loaded fully it should loop. If you want it to stop click on the button at “forecast.”
Though the European Model is not always right (none of them are) it has done the best job for the last two years in situations akin to this one with hurricane Irene. The National Weather Service gives credence to this model though you will not see it indicated on the official spaghetti charts and such. In fact, lately, the NWS official forecasts have been close to that of the ECMWF model runs or, if you please, the ECMWF model runs have been close to the official forecasts of the NWS. To be sure, there will be times when there is little agreement – at which time I expect to lean toward the NWS advisories.
THIS IS A TIME-SENSITIVE POSTING SUBMITTED 8-21-2011 AFTER 11 PM EASTERN TIME.
IT IS NOW OUT OF DATE. PLEASE CLICK ON THE BLOG TAB AT THE TOP LEFT OF THIS PAGE AND SCROLL DOWN TO LOOK FOR A MORE RECENT REPORT ON THIS STORM WHICH IS NOW A SERIOUS HURRICANE (posted 8-22-2011 near midnight EDT).
Invest (investigation) 97L (or 97AL) has become Tropical Storm Irene. My concerns for Florida remain and it looks to me as though the east coast is the part of Florida most likely to be influenced by the system. If it does skirt the coast at least that region will be subjected to the left-hand leading quadrant which is almost always less powerful than the right-hand leading quadrant. Based upon my observation of the ECMWF (European Centre for Medium-Range Weather Forecasting) model – it now looks as though South Carolina could very well be the landfall site. Of course many changes can occur over the next few days and much depends upon the movement and strength of a trough dipping down over the Eastern U.S.A. One of my favorite sources, Dr. Jeff Masters wrote yesterday:
“The best model for predicting the timing and strength of such troughs over the past two years has been the ECMWF (European Center model). The European Center does not permit public display of tropical storm positions from their hurricane tracking module of their model, so we are unable to put ECMWF forecasts on our computer model forecast page that plots positions from the other major models. Remember that a 7-day forecast by even our best model will be off by an average of over 700 miles, so it is too early to tell what part of the U.S. might be most at risk from a strike by 97L. This weekend would be a good time to go over your hurricane preparation.”
In the future, if you wish to view the ECMWF model loops go to the right of this page and under the heading of “Tropical Weather” click on the link to Penn. State U. Models Page. Scroll down until you find it.
Here is Jonathan Vigh’s spaghetti chart effort releases at 8 pm Eastern Time, 8-21-2011.
THIS IS A TIME-SENSITIVE POSTING SUBMITTED 8-20-2011 LATE MORNING EASTERN TIME.
Though there is more than one system out there today, my attention is east of the Lesser Antilles Islands where there is a system that currently has the status of a tropical wave. However, there is an 80% chance that it will become cyclonic within the next 48 hours. The Spaghetti chart below is courtesy of Jonathan Vigh. His efforts to put the model forecasts together produce my favorite renditions. Notice that the islands between its present location and Florida will be effected if this early visual is close to being correct. The storms ability to sustain itself as it moves over land might be touch and go. Frankly, this one really has my attention.
If you left click the image should enlarge – a second left click might enlarge it even further:
Left clicks on this graphic should enlarge it for you.
THIS IS A TIME-SENSITIVE POSTING SUBMITTED 7-30-2011 LATE EVENING.
This is the GFDL model’s forecast for system 91L 126 hours from the 2 PM Eastern time release (today 7-30-2011). Note that it is shown to be north of Eastern Cuba. I calculate the forecast time to be 5.25 days (or 5 days and 6 hours) beyond the release time. That would be Thursday, August 4 at 8 PM Eastern time. This, of course is a forecast loaded with unknowns and fickle variables so one should not consider it a “given.” The GFDL model (Geophysical Fluid Dynamics Laboratory) has impressed me over the last few years. I’m posting this now so that perhaps on Thursday night you might want to check to see how close it is. This posting is not intended to alarm anyone needlessly. If you are in a position where you like to plan ahead and are potentially in the path of tropical systems from the Atlantic and Gulf of Mexico, I advise you to pay close attention to forecasts available to you. It is my opinion that the Weather Channel on television does a great job covering tropical weather and I highly recommend it as a source. Also, on the right hand margin of this page under Miscellaneous/Other you will find a link to the on-line Weather Channel. I also highly recommend the tropical weather blog of Dr. Jeff Masters. Here is a link: http://www.wunderground.com/blog/JeffMasters/article.html
By the time you read this, May of 2011 will have ended and the Northern Hemisphere Atlantic, Caribbean, and Gulf of Mexico hurricane season will have begun. The following link will take you to a summary of the NOAA outlook for this season:
Please be prepared if you live in hurricane territory.
The loop above illustrates nicely that a tropical system does not have to be a hurricane in order to cause significant problems including fatalities. TO ACTIVATE YOU MUST LEFT CLICK ON THE IMAGE. Here is what Wikipedia has to say about the 2008 storm: Tropical Storm Fay was a tropical storm and the sixth named storm of the 2008 Atlantic hurricane season. Fay formed from a vigorous tropical wave on August 15 over the Dominican Republic. It passed over the island of Hispaniola, into the Gulf of Gonâve, across the island of Cuba, and made landfall on the Florida Keys late in the afternoon of August 18 before veering into the Gulf of Mexico. It again made landfall near Naples, Florida, in the early hours of August 19 and progressed northeast through the Florida peninsula, emerging into the Atlantic Ocean near Melbourne on August 20. Extensive flooding took place in parts of Florida as a result of its slow movement. On August 21, it made landfall again near New Smyrna Beach, Florida, moving due west across the Panhandle, crossing Gainesville and Panama City, Florida. As it zigzagged from water to land, it became the first storm in recorded history to make landfall in Florida four times. Thirty-six deaths were blamed on Fay. The storm also resulted in one of the most prolific tropical cyclone related tornado outbreaks on record. A total of 81 tornadoes touched down across five states, three of which were rated as EF2. Damage from Fay was heavy, estimated at $560 million.
Here is a link to Wikipedia’s coverage of that storm:
Here is a link to my list of 23 Misconceptions About Hurricanes:
FOR THE RECORD:
The “official” hurricane season is 6 months long – beginning June 1 – ending November 30.
An Atlantic hurricane was observed on March 7, 1908. That’s quite a number of days before June 1.
An Atlantic hurricane was observed December 31, 1954. That’s quite a number of days after November 30.
The earliest hurricane to strike the United States since 1900 was Alma which struck northwest Florida on June 9, 1966 and the latest was near the end of the day on November 30, 1925 near Tampa, Florida.
Here is a wonderful hurricane season summary by Dr. Jeff Masters of Weather Underground. Dr. Masters is one of my primary resources when it comes to tropical weather. At the end of his summary he links to the Klotzbach-Gray report which I have also linked you to below. But – for those interested in the “season” I recommend reading the Master’s report first.
Here’s the link to the comprehensive summary of the 2010 Atlantic/Gulf of Mexico/Caribbean hurricane season by Philip J. Klotzbach and William Gray. Gray is the renowned long-term forecaster from Colorado State University and Klotzbach, after a great deal of experience working with Gray, has taken over the primary responsibility. It is in the PDF format:
Though Tomas has weakened to a tropical depression, indications are that intensification to at least a category 1 hurricane will occur in the predicted journey northward. But, even as a lesser storm (tropical depression or tropical storm) the system can cause severe problems with fatalities. Just last month 23 people died in Haiti from the results of regular seasonal rainfall events, according to Dr. Jeff Masters’ blog this morning! The pitiful deforestation of that country allows for rapidly flooding streams and mass wasting events (e.g. mud slides) which can be deadly.
Certain deadly diseases can be spread by contaminated water which is a likely outcome of the flooding that Tomas will trigger. Cholera is probably the greatest current concern.
I am alarmed by the projected probability path of the storm (see this morning’s cone of uncertainty above) because, if it turns out this way, Haiti will be under the influence of the right hand leading quadrant of Tomas. That quadrant is typically the one possessing the strongest winds, most prominent storm surges, and greatest probability for imbedded mesoscale tornadic systems.
Of course, Haiti is not the only place that should be concerned. For example, the Dominican Republic, Jamaica, and the Bahamas need to be “ready.”
Even when you left click twice to get full enlargement, most of the individual model forecast plots are hard to read individually because of the “cluster” of agreement in anticipated general trend. The only glaring exception you see is the CLP-5 which should be no surprise to those who study these spaghetti charts. CLP-5 is the “CLImatology-PERsistance model 5-day” of the National Hurricane Center and is sometimes referred to as the CLIPER model for obvious reasons. It tends to project the path of tropical systems as though they were going to conform to their “past track.” So, more often than not, when there are changes in the steering influences the storms actually stray significantly from the persistence route. Most other models account for anticipated steering changes. This does not mean that the CLP-5 is of no value. To the contrary, it is very useful tool particularly in accessing forecast accuracy of other models.
It appears that Tomas could become a serious problem for Haiti. The country is over 98% deforested and that opens up a whole can of worms with regard to flooding, mud slides, and soil erosion. Some small fraction of the deforestation has been due to natural causes (e.g. Hurricane Hazel in 1954) but the vast majority has been due to the impact of humans and their practices upon the environment, the poor management of same, and the general human and political condition. It is my sincere hope that the storm weakens significantly but the National Hurricane Center currently has the “weighted mean” plot (within the cone of uncertainty) taking it through Haiti as a hurricane.
I copied this 2002 image below using my free Google Earth download. With yellow it shows a small part of the border between Haiti and the Dominican Republic at the Artibonite river. The greater amount of deforestation on the side of Haiti (west or left side of the river) is clearly evident. The eye altitude is 26,293 feet; a horizontal scale appears on the lower left.
My dear, long-time friend, Chuck Knighton, and his wife, Helen, are residents of northern Barbados and as of yet I have heard no news. I do know that they have frequent power interruptions with ordinary thunderstorm weather – so communication could be down for quite a while.
Update on that 1:40 pm EDT 11-1-2010 – An e-mail from Chuck’s mother:
Thanks so much for calling about the situation in Barbados! I have just recently spoken with Chuck’s sister in law who lives in the south of Barbados. She reports that they are all OK and the property sustained fallen trees and lots of rain! They do have household water, AND electricity (praise be!) and no one sustained injuries. Great news! They do not have phone service as yet, and I was really glad to have touched bases with someone!