From: NASA HQ
Posted: Wednesday, November 7, 2012
NASA's Aqua satellite captured an infrared image of the developing low pressure system off the Mid-Atlantic coast that is forecast to become a Nor'easter and bring winds, heavy surf, rain and snow to the Mid-Atlantic and Northeast today, Nov. 7 and tomorrow, Nov. 8. Nor'easters get their name from the continuously strong northeasterly winds blowing in from the ocean ahead of the storm and over the coastal areas.
When NASA's Aqua satellite passed over the low on Nov. 7 at 0705 UTC (3:05 a.m. EDT), it was already over the Atlantic Ocean. The Atmospheric Infrared Sounder or AIRS instrument aboard Aqua captured an infrared image of the storm that revealed cloud temperatures.
The AIRS image showed that the center of the low pressure area was well off the coast, but the northern and western extent of the storm was already over land, stretching from Mass. south to eastern Va. The low had moved east over the Atlantic after sliding off the coast of the Carolinas. By looking at AIRS infrared imagery, scientists can get a feel for how high the cloud tops are in the atmosphere. The higher the clouds, the colder they are and the stronger the storm. The lowest temperatures were as cold as or colder than 220 degrees Kelvin (purple) or minus 63 degrees Fahrenheit (-52 Celsius), indicating there was a lot of uplift in the air.
The National Weather Service has forecast the low pressure system to continue strengthening as it moves north along the coast today, Wednesday, (Nov. 7). The low is a cold-core system, not a warm core low pressure area, so it's unlike Hurricane Sandy that hit the previous week. This low will bring rain, snow, and/or a mixture of precipitation to areas across the northern Mid-Atlantic and Northeast, according to the National Weather Service. It will also pack wind gusts as high as 60 mph along the coast. Snowfall across interior sections of New England could approach 6-12 inches and coastal flooding is also possible.
The National Weather Service defines a nor'easter as "a strong low pressure system that affects the Mid-Atlantic and New England States. It can form over land or over the coastal waters. They can produce heavy snow, rain, and tremendous waves, beach erosion and structural damage. Wind gusts associated with these storms can exceed hurricane force in intensity.
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