WunderBlog Archive » Category 6™

Category 6 has moved! See the latest from Dr. Jeff Masters and Bob Henson here.

Ike pounds Haiti and the Bahamas; mandatory evacuation for the Keys

By: Dr. Jeff Masters, 3:20 PM GMT on September 07, 2008

Hurricane Ike is blasting Grand Inagua Island with Category 4 fury, as the storm heads towards eastern Cuba. Earlier this morning, a wunderground personal weather station in Providentiales in the Turks and Caicos Islands recorded sustained winds of 66 mph before failing. NHC reported another station closer to the eye of Ike had sustained winds of 115 mph. Damage will be extremely heavy on Great Inagua island today, which may receive a storm surge in excess of 13 feet. The latest satellite imagery and Hurricane Hunter data show little change to Ike, which remains a powerful Category 4 hurricane with 135 mph winds and extremely heavy rains. Recent microwave imagery (Figure 1) indicates Ike is lashing Haiti with heavy rains of up to 1/2 inch per hour. These heavy rains will cause deadly floods in the already hurricane-ravaged nation.


Figure 1. Estimated precipitation from Hurricane Ike. Image credit: Navy Research Lab, Monterey.

Track forecast for Ike
Ike has stopped moving west-southwest, and is now moving due west. A turn to the west-northwest is expected Monday. The latest 06Z (2 am EDT) computer models have shifted slightly north, but still predict Ike will track inland along the spine of Cuba for a day or longer. Along this track, Ike would likely weaken to a Category 2 or even a Category 1 hurricane. However, it would take only a very small deviation from the forecast track for Ike to spend much less time over Cuba and primarily track over the warm waters of the Florida Straits instead. While none of the models are currently predicting this, I give it a 30% chance that Ike will arrive at the Keys as a major hurricane of Category 3 or 4 strength because of an unexpected wobble to the north. The SHIPS intensity model predicts Ike will be a Category 4 hurricane with 135 mph winds if this happens. The Lower Keys including Key West are at greatest risk, and a maximum storm tide of 9-10 feet (Figure 2) can be expected in the Lower Keys in this scenario (storm tide is storm surge plus an adjustment in case Ike hits at high tide). I strongly encourage Keys residents to pay heed to the mandatory evacuation order and leave today. Ike could easily be much worse than Wilma was. If Ike does spend the expected 24-36 hours over Cuba, only tropical storm or Category 1 force winds are likely in the Keys.


Figure 2. Expected maximum storm tide (storm surge plus adjustment for hitting at high tide) from a Category 3 hurricane moving WNW at 15 mph through the Florida Keys, hitting at high tide. This plot is an ensemble of many different hurricane tracks (shown as black lines), not just one hurricane. The maximum surge from the ensemble is plotted here. The model used is NOAA's SLOSH model. Note that oceanside surge is a foot to two feet lower than bay-side surge. Bay-side surge comes well after the storm center has passed the Keys, from the westerly winds behind the storm. Too many people have been harmed because they thought it was safe to go near the water on the bay side just after a storm has passed. Image credit: Dr. Stephen Baig, NOAA (retired).

Once Ike emerges into the Gulf of Mexico on Tuesday, a trough of low pressure passing to the north may be able to induce a more north-northwesterly to Ike, and pull it towards the Florida Panhandle, bringing tropical storm force winds to Tampa on Wednesday. The HWRF is the only model showing this, and the rest of the models push Ike more to the west, into the central Gulf of Mexico. The eventual landfall locations predicted by the models range from Alabama to the Mexican border. It is too early to have a feel for where Ike will go at this point, since landfall is probably 6-7 days form now.

Intensity forecast for Ike
Sea surface temperatures (SSTs) have warmed to 29.5°C underneath Ike and will warm to 30.0°C over the Gulf of Mexico. Shear has dropped below 10 knots and is expected to remain below 10 knots for the next four days. As long as Ike is not over Cuba, it has very favorable conditions for intensification. Once Ike passes Cuba and enters the Gulf of Mexico, the intensification potential remains high, as shear is predicted to be below 15 knots, and the waters are hot.

Links to follow:

Holguin, Cuba radar
Punta De Maisi, Cuba weather
Punta Lucrecia, Cuba weather

Paying homage at the Key West Hurricane Grotto
If you live in Key West, I highly recommend a visit to the Hurricane Grotto to ask for some divine intervention in regards to Ike. There's a church in Key West called the St. Mary's Star of the Sea Roman Catholic Church. In 1922, a nun built a "hurricane grotto" on the grounds of the church in memory of the 600 who died during the great Atlantic-Gulf hurricane of Sept. 10, 1919, a Category 4 hurricane that made a direct hit on Key West. The nun vowed that as long as the grotto stood, Key West would not suffer the brunt of another hurricane. Key West residents regularly make pilgrimages to the grotto to pray for protection from hurricanes. And so far, the grotto has worked--no Key West resident has died from a hurricane strike since the 1919 hurricane.




Figure 3. Key West's famous Hurricane Grotto. Image credit: Cayogal.


As Hurricane Rita approached Key West in September of 2005, it was apparent that the magic of the Grotto would be severely tested. As I wrote in a blog the day after Rita passed:

Well, the protection of the grotto worked again. Key West barely escaped the brunt of a severe hurricane that could have been so very much worse. Had Rita's intensification cycle started 24 hours earlier, and she tracked 50 miles further north, the city of Key West would have been devastated. The Key West airport never measured sustained hurricane force winds from Rita, although the National Hurricane Center did receive an unofficial report of sustained winds of 75 mph with gusts to 102 mph in the Key West area. There was flooding and wind damage that will no doubt add up to tens of millions of dollars, but Key West is feeling lucky tonight. Key Westers, pay a visit to your grotto tomorrow and give thanks!


The tragedy in Haiti
As Ike pounds Haiti with torrential rains today, it is clear that Haiti will need massive assistance to recover from this latest disaster. If you're looking to contribute to the cause, I recommend the Lambi Fund of Haiti charity. I've been a contributor for a number of years, and have been impressed with their leadership and aims. The charity seeks not just to provide much needed temporary food aid, but to make investments in sustainable development in an effort to restore environmental integrity and reduce poverty. One of the main places my donations have gone is to fund the purchase and planting of thousands of trees on Haiti's denuded mountainsides. These treeless slopes, missing more than 98% of their original forest cover, allow flood waters from hurricanes to rush down and cause the mind-numbing loss of life we've grown to expect with each hurricane that affects Haiti. If you're looking to help out in the country in the Western Hemisphere that needs the most help, consider a donation to the Lambi Fund.


Figure 4. The flooded city of Gonaives after Hurricane Hanna, September 3, 2008. Image credit: Lambi Fund of Haiti.

I'll have an update between 4-5pm EDT today.

Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.