Hurricane Season 2009

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Orkaan Jimena op weg naar Mexico

LOS CABOS - Orkaan Jimena is in de nacht van maandag op dinsdag aangezwollen tot een storm van categorie vijf, de zwaarste schaal om de kracht van orkanen te meten. Dat heeft het Amerikaanse orkanencentrum in Miami gemeld.

Jimena is met windsnelheden van 250 kilometer per uur op weg naar Mexico, maar zal naar verwachting niet meer zo sterk zijn als de storm dinsdagavond aan land komt. Dat gebeurt vermoedelijk in Baja California.
Toeristen in dat gebied besluiten veelvuldig hun vakantie vroegtijdig af te breken. De vakantiegangers vrezen dagen vast te zullen zitten zodra de orkaan aan land komt. De autoriteiten hebben de inwoners van het gebied opgeroepen zich zo goed mogelijk voor te bereiden op de komst van Jimena. Tienduizend mensen zijn geėvacueerd.

Overstromingen

Er wordt naast de stevige wind ook veel regen voorspeld. Door de droogte van de afgelopen tijd kan de grond de regenval waarschijnlijk niet aan, waardoor ook gewaarschuwd wordt voor overstromingen.
De haven van Cabo San Lucas is uit voorzorg gesloten, hoewel de orkaan daar waarschijnlijk niet overheen zal razen. Ook is een top van de de Organisatie voor Economische Samenwerking en Ontwikkeling (OECD) verplaatst van Los Cabos naar Mexico-Stad.

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Op dinsdag 1 september 2009 15:34 schreef Tokamak het volgende:
El Nińo was ongunstig voor orkanen toch ?

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LOS CABOS, Mexico — Hurricane Jimena weakened to a Category 2 storm as it bore down on the coast of Mexico's Baja California peninsula.



Jimena's maximum sustained winds decreased late Tuesday to near 110 mph and the National Hurricane Center in Miami said it was expected to weaken further before making landfall Wednesday.

Jimena's change in status came a day after the hurricane brushed passed the resort towns at the southern tip of the Baja California, lashing them with driving rain and winds.

Despite the pummeling by the fringes of the then-Category 3 hurricane, the Mexican peninsula's biggest resort, Los Cabos, appeared to be escaping major damage beyond power outages and mud-choked roads.

Dozens of people evacuated from the Los Congrejos shantytown huddled in darkened rooms at a school after electricity failed during the storm. Trying to calm squalling babies and ignore hunger, the evacuees waited for dawn, and a chance to look at what the hurricane did to their homes made of plastic sheeting, wood and tar paper.

"Instead of giving out a few sheets of roofing every year, they should give us materials to build real houses — wood, or even bricks," said Paulino Hernandez, an out-of-work mason who sought haven at the school. "Every year it's the same thing: They (officials) give out a few sheets of roofing, and the next year it has to be replaced" when a hurricane comes.

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Aanzienlijke schade door Jimena
De orkaan Jimena heeft op het Mexicaanse schiereiland Neder-Californiė aanzienlijke schade aangericht en mogelijk ook een eerste slachtoffer gemaakt. De civiele bescherming meldt dat een visser vermist is opgegeven.

"Er is een persoon vermist opgegeven in de gemeente San Buto", op ongeveer 200 km ten noorden van de zone waar de orkaan gisteren de kust bereikte, aldus een woordvoerder van de civiele bescherming. "Het gaat om een visser die sinds dinsdag niet meer gezien is. Het is niet duidelijk of hij door een stortvloed is meegevoerd of dat hij zich op zee bevond."

De orkaan heeft tientallen huizen verwoest. Meerdere dorpen en steden kwamen zonder stroom te zitten, telefoonverkeer was op veel plaatsen onmogelijk en meerdere dorpen zijn door overstromingen van de buitenwereld afgesneden. (afp/adv)

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What is Erika gonna do
I cannot recall a more interesting situation as far as the future of a tropical storm like we are seeing with Erika right now. The NHC is continuing advisories on the poorly organized storm but looking at satellite pictures alone, you would think it was a well developed hurricane. The issue is, according to the latest discussions from the NHC, dry air and strong winds at just the right layers of the atmosphere.

These negative parameters are just enough to keep Erika firmly in check and may weaken it enough to be downgraded to a well defined tropical wave again. However, it is worth noting that the GFDL and HWRF models insist that Erika will become a major hurricane over the next five days as it travels just north of the Greater Antilles and towards the Bahamas.

What I do not understand is how these modern and seemingly reliable models can depict such a contrasting solution to what the NHC is forecasting: dissipation. Their reasoning has more to do with increasing strong winds aloft than anything- enough so that the official forecast calls for Erika to basically fade away as it travels west-northwest.

Yet, the GFDL and HWRF show robust intensification in to a strong hurricane along almost the same path that the NHC plots. So who will be right? The models or the humans? Computers are machines designed by people and so they are certainly prone to making mistakes- as we humans are. So it is likely that the human interpretation of the real world will win out and Eika will in fact die off and be of little concern to anyone. That is what seems most likely but it is not a guarantee. The old "what if?" keeps creeping in to my mind and believe me, Mike, Jesse and I have all talked about it at great length between yesterday and right now. Heck, even the Navy's NOGAPS model shows Erika making a comeback over a week from now with a strong storm or hurricane parked off the North Carolina coast.

So you see the dilemma that is inherent to this situation. I do not want to create something out of nothing when the people in charge of the forecasts present compelling evidence as to why this thing will die off. But so far, it is still there and looking fairly healthy considering the hostile environment. One thing is certain- unsettled weather will rule the picture over the Lesser Antilles and spread towards Puerto Rico today and tomorrow. Without this even having a name would not limit the heavy rains and gusty winds that are in store for much of the northeast Caribbean

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Weak season, but why?
The experts said that the hurricane season would likely be a weak one. So far, they have been spot on. Only hurricane Bill, which did become a category four, was much of a threat to anyone. Everything else has been about as poor as you could ever see from the tropics. But why has it been like this? One year ago we were tracking hurricane Ike which would go on to become a top-5 hurricane in United States' history. It came on the heels of hurricane Gustav which itself set records for wind speeds in Cuba. How can things be so dramatically different the very next year? Some blame it purely on El Nino but that is too simple. There are other larger forces at work here including cooler than normal sea surface temps in portions of the Atlantic where they need to be warmer in order to promote an unstable environment in which thunderstorms can develop and sustain. There is also a lot of sinking, dry air evident in the deep tropics, this too adds to the hostile conditions and goes strongly against development of tropical cyclones. Add to that what appears to be a weaker than normal Bermuda High, which allows strong upper level energy to dig off and near the East Coast, and you have the makings of a paltry hurricane season. Erika is a classic example of this even though some of the computer models insisted it would become a powerful hurricane. Those computer models are wrong, Erika is no longer a concern except for some rain associated with the low pressure trough that created it in the first place.

So what lies ahead for the rest of the season? It is only September 4 and yes, a lot can happen in the next six weeks or so that remains in the traditional meat of the season. We do see a few tropical waves across the eastern Atlantic that are moving westward in stealth mode- meaning they are essentially naked of any deep convection. They too will probably reach 50W longitude and begin to flare up, only to be snuffed out by hostile conditions. Of course, we know better than to completely dismiss the rest of the season as there is time for one to get through and ruin everything. In my opinion, the odds are against that happening but since we do not know for sure what lies ahead, we'll keep an eye out just in case

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Meanwhile, hurricane Fred continues to move slowly in the eastern Atlantic as it also weakens due to fairly hostile conditions. The interesting the thing about Fred is that the GFS model in particular, which goes out to 384 hours on each run, shows Fred's remnant low pressure area coming all the way back to Florida in about 10-11 days. It shows up as a tropical wave really with not much energy but it is there. It would be quite remarkable if it were to hold together enough to be of concern.

One reason I am interested in this a little more than usual is due to a pattern change that appears to be coming. Right now, most of the Atlantic is quite unfavorable for tropical storm formation. This is due to strong winds in the upper layers of the atmosphere as well as sinking, converging air. To get tropical storms and hurricanes, you need to see air in the upper levels that is diverging or spreading out as we would see with a large upper anticylone.

The latest GFS MJO forecast, which goes out to 15 days, indicates that the current negative pattern will cease and switch to one that is quite a bit more favorable- right at the end of the month and in to early October. This has to be watched closely as it is my belief, based on looking at longer range models, that the Caribbean Sea and Gulf of Mexico could get more active in the coming weeks.

It makes sense too climatologically as we begin to shift away from the eastern Atlantic and focus more on the western Basin towards the end of September. Let me be clear- there are no indications that a hurricane is in the works for any location. As I talk about often, these are just pieces of a large puzzle that we try to put together to figure out the picture of what may lie ahead in the tropics. What I see is the chance of a more favorable development pattern evolving. Whether or not anything actually happens during that pattern remains to be seen.