Ike threatens disaster on a large scale; CA weather may become more interesting

Hurricane Ike has now been a named storm for well over a week. It’s path–beginning 300 miles west of the Cape Verde Islands and passing south of the Bahamas as a powerful category 4 hurricane, then crossing over eastern Cuba and re-emerging in the Gulf of Mexico after a second transit over land west of Havana as a weakened category one storm, and (to bring us to the present time) curving westward once again over the Gulf of Mexico and strengthening dramatically–has been hard to call more than 12-24 hours in advance. Even stranger than its path, though, has been the structure and evolution that the storm has exhibited since re-emerging over the Gulf. Ike was originally expected to re-intensify into a major hurricane, most likely a very impressive category 4 or 5 storm, by Tuesday or Wednesday. Instead of increasing winds, however, Ike began to increase dramatically in size. The radius of hurricane-force winds is now over 115 miles (that’s a 230 mile stretch of sustained hurricane-force winds!) and the radius of tropical storm-force winds extends well beyond 200 miles from the center (400+  mile diamater). This is significantly larger than almost any other hurricane ever recorded outside of the West Pacific, and even exceeds the respective diameters of winds in Hurricane Katrina at her peak. Ike currently has sustained winds of around 100 mph, which makes him a category 2 storm. The slow movement of the storm, the consistent direction of motion, and the increasingly shallow continental shelf off the coast of Texas are contributing to a truly remarkable–and potentially devastating–storm surge. Serious coastal flooding has already occurred in every Gulf Coast state, including Florida (to the east of the storm and nearly 500 miles from the center of circulation). Even if Ike does not strengthen any further and makes landfall as a category 2 storm, the coastal inundation in the Galveston area will be incredible (on the order of 20+ feet). The major seawall in Galveston–built after the 1900 hurricane which killed as many as 10,000 people in that city and is still the deadliest natural disaster in U.S. history–is only 17 feet high. The mayor of Galveston did not order any sort of evacuation until this afternoon, and this gives the entire area significantly less than 24 hours to evacuate. Contingency plans call for at least 72 hours to completely evacuate the city. At the current time, 75% of residents are still on the barrier island. Ike has the potential to be an extremely serious hurricane as it makes landfall late tomorrow night in Texas. Additional strengthening is still possible, as infrared satellite imagery does indicate much better outflow in the western semicircle of the storm over the past 6 hours and much more extensive deep convection around the center of circulation. Although there is not a distinct eye visible at the current time, I do believe that the emergence of one is very possible at some point during the next 6-18 hours. Stay tuned–this storm has much more potential than Gustav to cause massive damage and extensive loss of life, and could rival Katrina in more than one respect. Stay tuned.

 Our rather more docile weather back in CA will nevertheless become at least somewhat more interesting over the next 4-7 days. Seasonal temperatures and  no significant weather will occur trough day 5. Then…the GFS and ECMWF both bring a cutoff low off the CA coast. This low may stick around for a while, and at the current time both models indicate that enough subtropical moisture could be entrained around the eastern circulation of the low that CA may stand a chance at some convective activity. This is still a ways out, but there is also quite a bit of model continuity with the scenario. Certainly, it will be worth keeping an eye on…