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Emily churning through Gulf of Mexico

By: Dr. Jeff Masters, 6:44 PM GMT on July 18, 2005


Posted: 2pm EDT Monday July 17
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Emily is now a Category 1 hurricane. The 1:22pm EDT Hurricane Hunter mission found a central pressure of 984 mb and peak winds at 10,000 feet on the NE side of 89 mph, which would make Emily's surface winds about 75 mph. Satellite imagery shows a large area of dry air spiraling north from the Yucatan Peninsula and wrapping into the center of the hurricane. This dry air is severely weakening Emily. The storm has a more ragged appearance than when it moved off the coast at 9am, and the lack of convection on the south side has expanded.

Emily has shown great resilience, and may still regain Category 3 status when she moves further away from the Yucatan and stops pulling in so much dry air. However, the kind of disruption of the inner core that appears to be happening usually takes at least a day for a hurricane to recover from, and Emily has only 36 hours before landfall. It is unlikely Emily will be stronger than a Category 2 storm at its next landfall.

Posted: 10am EDT Monday July 17
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Emily made landfall at 2am EDT this morning as a Category 4 storm with peak winds of 135 mph and a central pressure of 955 mb. The eye passed just southwest of Cozumel, Mexico, with the northern eyewall passing over Cozumel. No wind, pressure, or damage reports have emerged from Mexico yet, but the 8 - 12 foot storm surge and 135 mph winds must have done tremendous damage.

Emily's eye moved off the coast of Mexico at approximately 9am EDT this morning, after spending just seven hours over the Yucatan Peninsula. The hurricane has survived the crossing fairly intact, as a Category 2 hurricane. The storm looks somewhat lopsided, with a notable lack of cloudiness on the south side where dry air from the Yucatan has been drawn in. However, the eye is still distinct, a decent-looking circular Cirrus Dense Overcast still covers the center of the hurricane, and Emily has exellent-looking spiral banding. This is the look of a hurricane that has been only temporarily disrupted, and will soon begin strengthening. There is plenty of warm water ahead of the hurricane, and low vertical wind shear. I see nothing that will prevent Emily from reaching Category 3 status by tomorrow, perhaps even a strong Category 3.

The track forecast remains pretty much the same, with Mexico expected to receive a second pounding early Wednesday morning when Emily comes ashore about 50 miles south of the Texas border. The median track error the past 10 years for a 36-hour forecast is over 100 miles, so Emily could still hit Texas. However, the NHC has done an great job forecasting this hurricane the past seven days. The five-day forecast issued five days ago put the landfall of Emily as a Category 3 storm directly over Cozumel, and was in error by less than 75 miles. This is a pretty excellent forecast, considering the median error for a 5-day forecast is 310 miles. Since that forecast was issued, the forecast errors for 3-day forecasts have been below 100 miles every day. And with the NOAA jet up in the air sampling Emily's large scale environment each of the past two days, the reliabililty of the current and future forecasts is likely to continue to be excellent. Thus, the chances of Texas getting a direct hit from Emily is less than 25%.

Jamaica was largely spared yesterday, as Emily passed 100 miles south of the island and brought them only tropical storm force winds. However, torrential rains caused serious flooding damage and was responsible for sweeping five people to their deaths when they drove past a closed road blockade and were swept over a cliff by floodwaters.

The Cayman Islands, which Emily missed by only 85 miles, also escaped serious damage. As reported by WunderBlogger CaymanMike:, "Wow! Grand Cayman and the Sister Islands made it through our brush with Emily with nothing more than some gusty tropical storm force winds and some heavy rains. The official word from the government is that the power stayed on over the island, the airport has reopened and no major damage is reported."

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