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Ophelia brushing Bermuda; Super Typhoon Nalgae hits the Philippines

By: Dr. Jeff Masters, 4:50 PM GMT on October 01, 2011

Hurricane Ophelia is steaming northwards to the east of Bermuda as a powerful Category 3 hurricane with 120 mph winds. Radar out of Bermuda shows that rain bands from Ophelia are beginning to affect the island, though as of noon Saturday, the Bermuda airport has reported just one brief rain shower and a peak wind gust of 21 mph. Recent satellite loops show that Ophelia is well-organized, with a prominent eye, good upper-level outflow, and solid lower-level spiral banding. The models agree that Ophelia will track far enough to the east of Bermuda that the island should see sustained winds below 30 mph, since it will be on the weak (left) side of the storm. The 11 am wind probability forecast from NHC gave Bermuda a 19% chance of receiving tropical storm force winds of 39 mph, and no chance of receiving hurricane force winds. Ophelia's closest approach to the island will be late Saturday night through early Sunday morning. Ophelia is likely to bring high winds and heavy rains to Southeast Newfoundland Monday. The 11 am wind probability forecast for Cape Race, Newfoundland gave it a 47% chance of receiving tropical storm force winds, and a 1% chance of hurricane force winds.

Figure 2. Morning satellite image of Ophelia.

Tropical Storm Philippe no threat to land
In the middle Atlantic, Tropical Storm Philippe continues to struggle against dry air and high wind shear. Satellite loops show Philippe is a small system with little heavy thunderstorm activity, with the surface circulation partially exposed to view by wind shear. Wind shear is a very high 30 - 40 knots, thanks to the upper-level outflow from Ophelia. This shear will remain high through Tuesday, but may relax to the moderate range as Philippe turns towards the north on Wednesday. It is unlikely that Philippe will trouble any land areas.

Elsewhere in the Atlantic, none of the computer models is calling for a new tropical storm to form in the coming seven days (though the NOGAPS model shows a strong tropical disturbance forming in the Western Caribbean in about 7 days, something it has erroneously been predicting frequently during the past few weeks.) The large-scale environment over the Atlantic currently favors sinking air, due to the current phase of the Madden-Julian Oscillation (MJO). This situation will likely last well into next week, and will discourage formation of new tropical storms. The MJO is a 30 - 60 day cycle of thunderstorm activity that affects the tropics.

Figure 2. True-color MODIS image of Typhoon Nalgae approaching the Philippine Islands, taken at 02:15 UTC Friday, September 30, 2011. At the time, Nalgae was a strengthening Category 1 typhoon with 90 mph winds. Image credit: NASA.

Super Typhoon Nalgae hits the Philippines
Typhoon Nalgae roared ashore over the Philippines' main island of Luzon as a super typhoon with 150 mph winds at 9 am local time this morning. Nalgae dumped heavy rains of 4 - 8 inches across a large swath of Northern Luzon; 4.81" of rain fell on Viganon the northwest coast of Luzon. The capital of Manila received 0.30" of rain from Nalgae, and experienced wind gusts up to 36 mph. Nalgae is the second major typhoon in a week to hit northern Luzon; on Monday, Typhoon Nesat hit the same region as a Category 3 storm with 120 mph winds, killing at least 52 people. Nalgae's rains fell on soils already saturated from Nesat's heavy rains, and the potential exists for high loss of life due to extreme flooding and mudslides. Nalgae is expected to follow a track almost exactly the same as Nesat's, passing near China's Hainan Island on Tuesday, and then hitting northern Vietnam.

Jeff Masters


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