Tuesday, December 23, 2008

Snow Storm #3 - Coastal Frontogenesis


Click image to animate.

Note the sharp temperature gradient between PWM and Buoy 44005. The buoy is located 78 NM east of PWM.



Rapid deepening of -2.7 mb / hr at 00z concurrent with strongest horizontal temperature gradient of 0.372°F / NM. Strong temperature gradients initiate ageostrophic circulations across the boundary leading to pressure falls and upward vertical motion.

PWM observed a record 14.5" snowfall from this storm. The old record of 12.4" was set in 1933. Snow totals are often suppressed at PWM b/c of its proximity to the coast; however...in this case...the station remained on the cold side of the coastal front and all precipitation fell as snow.

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