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Posted at 11:09 AM ET, 09/27/2012

Textbook storm explodes near Alaska


Satellite image of storm in Gulf of Alaska Wednesdayat 7:30 EDT (Naval Research Laboratory)
In the Gulf of Alaska, a stunning storm has blown up like a bomb.

Yesterday, this storm’s pressure dropped 42 millibars (mb) in just 24 hours and 26 mb in 12 hours alone. In introductory meteorology classes, you are taught a 24 mb drop in pressure in 24 hours meets the criteria for “rapid intensification”, referred to by some as “bombogenesis”. This storm exceeded that criteria, easily.


Surface map showing Alaska storm at 2 a.m. EDT Thursday (NOAA)
Overnight, the storm’s minimum central pressure dropped to around 956 mb which is deeper than hurricane Isaac at its peak (968 mb). But because the storm is some distance offshore, mainland Alaska may not get the same beating it got from storms earlier this month.

The Anchorage Daily News writes: “[The storm] is not forecast to bring comparable amounts of water and wind over the mountains into Southcentral as other recent, powerful storms, according to the weather service.”

Nevertheless, heavy weather is expected along the south central coast.

The Alaska Dispatch writes: “Rain, sometimes heavy, is forecast for Seward, Valdez and Cordova, with winds accelerating through mountain passes. Flood warnings have been posted for the eastern Kenai Peninsula and the Copper River basin.”

The storm is forecast to weaken today, with the central pressure rising to around 972 mb.


Forecast for Alaska storm today (NOAA)

This cyclone over the Gulf of Alaska is just one of at least 3 notably intense storms swirling over the world’s oceans in recent days.

* In the western Pacific, super typhoon Jelawat intensified from a tropical storm with 65 mph to a category 4 super typhoon with 140 mph winds in just 24 hours earlier this week

* An Atlantic storm with a pressure of 973 mb hit the United Kingdom, the deepest storm to hit Britain since 1981

By  |  11:09 AM ET, 09/27/2012

Categories:  Latest, U.S. Weather

 
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