by Glenn "Hurricane" Schwartz
First things, first. Hurricane Fiona is about to make history in Nova Scotia and Labrador. Even though it will be tracking over cooler water before landfall, that won't cause the monstrous waves to diminish. They have been building on the east side of the track for nearly 2000 miles by the time landfall happens.
Fiona will also transition from a pure tropical system, but don't let any "weakening" or change in structure fool you. It sure did for many in Sandy, ten years ago. Even the mayor of NYC, Michael Bloomberg got some bad advice and announced that "Good news: Sandy has weakened". But there was a buildup of 1000 miles of ocean winds that led to storm surge records beyond belief.
Similarly, Katrina also "weakened" before landfall, but it was a Category 5 building those monstrous waves out in the Gulf.
Details remain to be determined, but the name "Fiona" will end up never being used again for an Atlantic tropical system (they retire the names of the worst ones).
By comparison, the developing storm to be named Ian is still looking weak. But don't let that fool you, either. The center is becoming more obvious, it has moved farther away from South America, and thunderstorms are increasing around the center. That is the start of organization. But by next week at this time, Ian may have done enough damage for its name to be retired eventually as well.
There are several reasons why Ian is likely to become a major hurricane:
- Going into some of the warmest water in the world, and warm to a great depth, too
- Moving into one of the historically favorable areas for rapid strengthening
- A sharp drop in wind shear, and a general lack of shear for days
- A predicted track either over water or small land areas until a U.S. strike. The biggest impediment could be some mountains in Western Cuba, but they're not nearly as high as those in Eastern Cuba.
- The computer models show strong signs of rapid intensification over the weekend.
Meteorologist Jack Sillin often tweets the most impressive maps, models, and details on social media.
The red lines around much of the coast of Florida show where the main threats are next week. But the range of possible tracks are bounded by the blue arrows (wouldn't it be nice if the farthest east solution was right?).
One of the things he shows is called a "Super-ensemble". I've shown the 51 ensemble tracks of the European model this month, but this also includes ensembles of the GFS (U.S.), GPS (Canadian) and UKMET (U.K.). This reinforces the general future track of Ian.
The predicted track looks quite similar to Hurricane Charley in 2004:
Charlie was a Category 2 hurricane as it crossed Cuba but intensified quickly into a Category 4 as it slammed into the Southwest Florida coast. Some lessons from Charley (especially compared to Ian's forecast):
- Charley was an unusually small storm. Places 50 miles north or south of the track had minimal damage. Ian is a MUCH larger storm.
- Too many people got suckered into the dots and lines of the official forecasts. Those suggested an eye going over Tampa (which would have been a worst-case scenario, so it got all the publicity). The Fort Myers/Port Charlotte area was in the hurricane warning area, but there was plenty of surprise when it hit.
- Charley was moving rapidly and didn't weaken very fast. It tracked right over Orlando and caused a lot of damage there. Even inland areas of Florida (and the Florida east coast can be threatened.
So, just because your town isn't on the forecast line, don't assume you'll be in the clear. Just about all of Florida needs to be prepared for a possible major hurricane strike next week.