Late PM Update: Earlier this evening, Cuban radar showed a well-defined eye for Gustav, but later radar and satellite imagery pictured a more ragged structure, so the storm was downgraded to a tropical storm at 11 pm. Maximum winds are still estimated at 70 mph, and restrengthening is likely tomorrow as the storm moves more over water. There has been little change in the forecast track, which takes Gustav between Jamaica and southeastern Cuba by Thursday. At that point, it could reach as high as Category 2, and the official forecast brings it to near Category 4 at 72 hours (Friday night).
8 pm Update: Maximum winds for Hurricane Gustav remain at 75 mph as of the latest advisory. The center was located about 60 miles west of Port Au Prince, Haiti and about 155 miles southeast of Guantanamo, Cuba.
Some fluctuations in intensity are likely tonight, but it should strengthen again as it moves back over the water of the Windward Passage tomorrow. As shown in the second chart on the right, Gustav will be moving over an area with some of the highest Tropical Cyclone Heat Potential (TCHP) in the Atlantic basin.
5 pm Update: Hurricane Gustav has weakened over southwestern Haiti to 75 mph. It may weaken further to below hurricane strength overnight before moving back over water east of Cuba. The upper level environment is also favorable for development, with very low wind shear. Gustav is moving toward the northwest at a little slower pace, about 10 mph. Jeff Masters reports in his blog that Gustav tied the record of Humberto from last year for the fastest time from initial advisory to Category 1 hurricane.
Natural gas prices ended trading slightly down from their highs, but still up 5.3% for the day.
Hurricane Gustav made its first landfall on southwestern Haiti early this afternoon. The storm is still at Category 1 strength with maximum winds of 90 mph. Some weakening is likely from the interaction of Gustav's relatively small circulation with Haiti, but then restrengthening is expected over the warm waters between Haiti and southeastern Cuba. There is a large uncertainty in position and intensity after day 3, but the official track takes the storm over the far western tip of Cuba and into the Gulf of Mexico by this weekend. Gustav's potential threat to the Gulf is helping to keep natural gas prices near the high for the day, up 6.6%.
In other tropical news, Stu Ostro does his usual thorough and colorful job of reviewing "Fay's nine lives" at The Weather Channel blog.
Images: Gustav forecast track from National Hurricane Center, TCHP from NOAA/AOML, U.S. Natural Gas fund 5-day prices from BigCharts.com, via Fidelity Investments
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