Thursday, January 31, 2013

Windswept, Soaked, Blustered

Last night's wind and rain storm produced some significant wind gusts between Midnight and 4 AM along and east of I-95.  Winds gusted across coastal sections of Delaware and New Jersey to and just over 60 mph, punctuated by 63 mph wind gusts at Lewes and Sandy Hook.  In Philadelphia, wind gusts officially topped out at 45 mph at the Airport but an observer to the Weather Service reported a 53 mph wind gust as the squall line moved through around 3:30 this morning.  Winds generally were strongest along and east of the river, which was in line with modeling and forecasts for the storm as the low level jet was projected to really be the most intense east of the city.

Rainfall was projected to be higher to the west -- and it was.  The city through 5 AM picked up just shy of an inch of rainfall but those totals quickly picked up as one traveled west.  Two to three inches of rain was common across Western Chester, Western Montgomery, Berks and the Lehigh Valley, and Northern Lancaster Counties. The highest "official" total so far came in from Lancaster at 2.55" for the storm.

Doppler radar estimates from the storm through just before 6 AM show that gradient to our west.  This was largely due to rain progressing in a "train" like fashion to the city's west.  The lower level jet that pushed northeast yesterday evening helped punch a dry (but windy) slot north into South Jersey and Delaware while keeping the bulk of the rain to the city's west.  There has been some minor stream flooding on the usual suspect streams in the western suburbs down into Wilmington early this morning -- the formerly frozen ground provided very little support for a heavier rainfall and the result was a rather easy and rapid runoff of rains into streams around the region.

There's been question regarding the last "big" January storm that produced wind swept rains.  It occurred three years ago -- January 24th & 25th, 2010 when we picked up one to two inches of rain, along with winds that gusted (ironically) to 44 mph in Philadelphia, similar to last night's storm.