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Dr. William Gray, Philip Klotzbach, issue October tropical forecast

The latest hurricane forecast from Dr. William Gray (the "Hurricane Doctor") and Philip Klotzbach at Colorado State University is out, focusing upon the month of October.

"Information obtained through 30 September 2008 shows that we have so far experienced 124 percent of the average of a full season’s Net Tropical Cyclone (NTC) activity and about 155 percent of the long-period average season through September. We correctly predicted above-average September NTC, although we predicted more activity than was observed.
Our October-only forecast calls for 3 named storms, 2 hurricanes, 1 major hurricane and NTC activity of 35 which is well above the October-only average value of 18. This is due to..." Click here to link to the full report as a PDF file.

Is Kyle a dud? Why I'm not too excited about him, even for Cape Cod or Eastern Maine

Well, here's the honest analysis:  Kyle has strengthened.  He's a hurricane and his thunderstorms near the center look better than ever, with infrared satellite imagery showing the coldest cloud tops of his lifetime.  There are signs of these thunderstorms wrapping around the northwestern periphery of the storm, and Tropical Storm Warnings (for sustained winds of 39 mph or greater) are up for Eastern Maine, as well as a Hurricane Watch (the possibility, though not imminent, of 74 mph winds or greater), with a Tropical Storm Watch up all the way south through Portland to Cape Elizabeth, on the Southern Maine coastline.  It's absolutely essential that folks prepare as directed by the National Weather Service.  I'll write it again - it's absolutely essential that folks in the warned area prepare for tropical storm force winds by securing vessels on the dock, taking in lightweight objects, and being prepared for some power outages.  Having said that, this meteorologist has serious doubts that we will get a single tropical storm force (39 mph or greater) gust in New England as Kyle passes by.  Here's why:

• Kyle has yet to develop convection (thunderstorms) on his west side.  This is usually necessary to bring strong winds down to the surface.
• There have been indications that the strengthening thunderstorm mass has been attempting to wrap around the north side of the circulation, but the storm's acceleration to the northeast keeps inhibiting this from happening
• Kyle is expected to continue accelerating northeast
• There is excellent agreement among the guidance that the storm will go just east of the National Hurricane Center track, passing just off the western coast of Nova Scotia (image is courtesy Jonathan Vigh, Colorado State Univ.  For more info, click here).
• Buoy and ship reports, as well as satellite estimated winds, on the west side of the storm show no sustained wind greater than 22 mph, though sustained winds to 45 mph are found due north of the circulation center
• The storm will soon move over waters cool enough to lead to weakening as a tropical system, meaning the storm will become "extratropical," or non-tropical
• In order to get symmetric winds - that is, strong winds on both the east and west side of the storm circulation - we either need to have a truly tropical cyclone (not going to happen over cool water and given the extratropical transition described above) or a quick and potent transition to a strong non-tropical cyclone that will spread wind away from the center.  Such a transition requires a strong, energetic disturbance in the jet stream to enhance the storm's transition
• We have no such strong disturbance aloft that will interact with Kyle
• This leaves us with a slowly decaying storm that will be undergoing a slow extratropical transition, given no upper level jet stream disturbance to hasten its transition
• There is nearly unanimous agreement among the intensity guidance (see image...same credit as the previous) that the result is a steadily weakening storm that is reduced to weak Tropical Storm or perhaps even Tropical Depression strength (sustained winds less than 39 mph) by the time it passes just west of Nova Scotia, and given the above factors I'd expect those winds to be on the east side of the storm

Put all of this together, and I'd be surprised to find ANY gusts (let alone sustained wind) to tropical storm force - 34 mph or greater - on land in New England.  The best chance may be at the buoy off the Downeast coast near Jonesport, at buoy #44027.

Is this wise to go against the National Hurricane Center's forecast?  Am I jeopardizing lives and property by saying this?  Well, keep in mind that I have the luxury of NOT being on the air this weekend - these are thoughts I can share with you between two weather-inclined folks.  The forecasters at the National Hurricane Center are among the best in the world - true experts in the field - and that's why all folks in the warned area MUST make preparations.  Having said that, New England tropical cyclones are among the trickiest in the world, and Kyle is no exception to the rule.  Sunday we'll find out what reality brings.

Do you think I'm nuts?  Do you agree?  Add your thoughts in the comments section!

Matt

Kyle is born...what happens next?

Kyle looks rather sad with his lopsided convection, but the thunderstorms east of the center are build well with cold cloud tops.  The shear north of the storm has been up to 50 knots - extremely strong shear that would tear any storm to pieces - but has been decreasing dramatically in the last few hours and should remain low to moderate in the next two days.  There is decent agreement among the hurricane guidance products on intensifying the storm to minimal hurricane strength at 48 hours (Saturday morning) with a Sunday AM passage over the Eastern Gulf of Maine.

There are some new questions that come to mind and must be answered in the next 12 to 18 hours.

1. Will the storm move as slowly as forecasted, or will it sling quickly north in the developing southerly flow?
2. Will this same southerly flow tear the top off the storm and effectively leave the surface circulation behind while the tropical moisture surges northward?
3. Will the warm front backing in from the ocean across New England, then stalling, serve as a boundary to focus more heavy rainfall than was initially expected, making it last longer through Saturday and into Sunday, or is the front too far removed from the storm to have this effect?
4. Will Kyle perform much like a poleward moving tropical cyclone and have a distinct separation of wind to the south and east of the track, and heaviest rain west, or will the combination of the frontal boundary and the increasing pressure gradient ahead of the high building over Southern Canada increase wind on the west side of the storm circulation?
5. How will the lack of convection on the west side play out in the life and longevity of the storm?
6. Will the rather ominous ECMWF (pictured below) verify?  It certainly is west of the hurricane track guidance, but is disconcerting to consider as a possible solution.

For me, I need some rest and will re-examine these questions in the morning (getting up at 2 AM will do that to a guy!).  But, if you have thoughts you'd like me to read when I sit down to analyze everything in the early AM, feel free to leave them in the comments section of this post!  In the meantime, check out tropical analysis and forecasting links on the Tropical Page of NationalWeatherOnline.com.

Matt

A shell game in the tropics...attention shifts to the Carolina coastline

With one much-talked about but lackluster tropical wave failing to produce, a creepy Carolina creature crawls coastward...

Click "continue reading" below to read the entire post.

A forecasting conundrum with the tropical wave

An intriguing scenario becomes even more intriguing, it seems.  It's one thing to be a week out, watching a tropical wave and seeing guidance forecasts for the disturbance to ramp up and head to New England.  It gets a bit stale when you're still doing the same thing on Tuesday, and the timeframe in question is Friday night or early Saturday.  I'm aware that I've been significantly downplaying this system contrasted with at least a few other media outlets - no mention of potential wind or rainfall amounts in my forecasts yet - but, let's look at this realistically...

When weather takes on a life of its own

It's begun.  Already.  The questions gaining momentum today are "Is it coming?" "When's it getting here?" and "What's going to happen with that hurricane down in the tropics?"

Keep in mind, that as of this writing we have neither a hurricane, nor a tropical storm, nor even a tropical depression.  In fact, thus far we have an open tropical wave with no official closed surface circulation (that may change when hurricane hunters report back)- in other words, a cluster of thunderstorms.  Granted, it's an impressive cluster that's dropped over 10 inches of rain in Puerto Rico.  And, granted, upper level winds have been becoming more favorable with outflow improving, allowing for sustained thunderstorms.  But there are issues with this, too.  Not only is it difficult to define any center of circulation (recon aircraft is investigating - there could be a small circulation with limited convection just east of the Dominican), but wind shear is rather significant in the middle and upper levels both north and south of the wave.  Additionally, steering currents in the middle and lower levels are still from east to west, not a northward flow.

All of these factors argue against any development.  In favor of development is the already good structure of the convection, warm ocean water, and a number of guidance products - including all hurricane guidance products - that spin the system up.  In the latest frames of the afternoon visible satellite loop, it becomes evident that a small circulation may be intact, over land, over the eastern tip of the Dominican.  This is also where, in the IR satellite image here, enhanced thunderstorm tops are showing up north of the main thunderstorm cluster.

Right now, there are far more uncertainties than certainties about whether this thing will ever even develop a closed circulation, let alone ramp up, and certainly not whether the storm will take one track or another if it does develop. 

But, alas, we as a society love something to watch and worry about.  Of course, there IS plenty that we could worry about with this storm - a forecast track into the Mid-Atlantic coast around Delmarva is one possibility that would be devastating for parts of Jersey, Delaware and MD.  A New England pass probably would go southeast of us but could bring a strong and damaging nor'easter.  But, before we get too carried away...we need a storm.  :)

Any thoughts on this, folks?  Comments are open on all the posts!

HURRICANE BERTHA SETTING RECORD FOR LONGEST-LIVED JULY TROPICAL CYCLONE IN ATLANTIC BASIN

(Photo courtesy NOAA) Hurricane Bertha continues to spin over the Central North Atlantic.  Although she has begun a trend that will eventually lead her to become a non-tropical system, and therefore be pronounced dead by the National Hurricane Center, every moment she's alive and well adds to her history-making feat.  Bertha may not be remembered for her intensity - reaching hurricane strength but bringing only tropical storm force winds to Bermuda and her center never making landfall, but she will be remembered in the meteorological community for her duration.  Bertha continues to churn as the longest-lived July tropical cyclone on record in the Atlantic Basin.  This article from MSNBC examines Bertha's feat.

HURRICANE FORECASTS: FRIEND, FOE, OR JUST GUIDANCE?

(Photo courtesy of Gerry Broome, AP)  Perhaps one of the most exciting, anticipated, and then questioned forecasts in the world of meteorology is the seasonal hurricane forecast.  One of the first to publicize seasonal hurricane forecasts was Dr. William Gray, at Colorado State University, who became known as "The Hurricane Doctor," as his predictions often have been quite accurate.  There have been years that have not verified well, and since Dr. Gray began his forecast several years ago, the National Oceanic and Atmospheric Administration began seasonal hurricane forecasts as a government entity, and many private companies jumped on-board, as well.  Unfortunately, this had given the false perception for the general public that seasonal forecasts were always going to be fairly accurate when, like any forecast, they should be taken as guidance and not used verbatim.  This was a difficult lesson learned in 2006 - following the most active tropical Atlantic season in recorded history - by a number of insurance companies who bought completely into a forecast for an active season, and took high stakes gambles on the forecasts that resulted in bankruptcy.

A couple of articles have come out as of late, pertaining to hurricane forecasts:

National Geographic News takes a look at the updated forecast from Colorado State University - Dr. Gray and his relatively new partner, Bridgewater State College graduate Phil Klotzbach.  Of course, the Associated Press reminds us not to put too much stock in the seasonal hurricane forecasts, and actually does a pretty fair job of explaining that such forecasts are not intended to be the gospel of weather. 

HURRICANES TO DRIVE GAS PRICES HIGHER?

Though I believe there's a great deal of alarmism that plays into such reports and predictions, the talk has fired up again that an active hurricane season in 2008 could drive already record-high gasoline prices even higher, specifically if cyclones affect the drilling platforms.  To me, perhaps the most bothersome part of this equation is the emotional state of the oil market - the mere entrance to hurricane season...without any storm in the Gulf...has already driven prices up, and that trend is expected to continue.  In fact, it's rather remarkable to see in the past couple of seasons the way oil prices and futures respond instantly to new revisions of forecasts from the National Hurricane Center - a move toward the Gulf, even if forecasted incorrectly, jacks prices up.  Click here to read the article on 2008 gas price dependency on the hurricane season from CNN.com.

TROPICAL CYCLONES AND CLIMATE CHANGE: THE LINK IS STILL FUZZY, AND DEBATED

Cyclone Nargis was only the latest major storm to make headlines as it roared ashore in Burma with widespread and significant death and destruction.  Are tropical storms - and storms in general - getting stronger than they've ever been?  If they are, is climate change to blame?  The international AFP news organization examines this issue from France, and discovers nothing too groundbreaking - there is great debate among even the most intelligent scientists.

Have a thought on this item?  Share it in the comments section of this post!