Sunday, July 01, 2012

Weather Rewind: June 24-30, 2012

Despite our second heat wave of the year last week, temperatures only topped out 1.6 degrees above average.  You can thank Tuesday's 80 degree high and a wondrously comfortable couple of days during the middle of the week for keeping the weekly average in check.  That said, Friday's 98 degree high was the highest of the year so far, which included a couple of 100 degree readings across Southern Delaware (101 in Georgetown, DE) as well as a plethora of heat across Maryland and DC.

That heat came with a tremendous price on Friday night with the Midwest to Mid-Atlantic Derecho event that crossed over 1000 miles of real estate in 17 hours.  Cleanup from that event will take several days but was part of a rather stormy day on Friday as a morning squall line zipped southeast through the Philadelphia area and brought a loud wake up with gusty winds and some hail.   Outside of the severe weather events, rainfall was rather modest through the region last week.

Nationally, temperatures for June were hottest in the Plains, where dry weather plus a ridge of high pressure that had been parked over the Plains for much of the month lead to all-time record highs being set in Colorado, Kansas, and Nebraska.  That heat transported eastward on occasion, with the brunt of summer heat pushing east this week and setting records through the South (all-timers set in Nashville, Atlanta, and a host of other locations to our south).  Much of this heat originated in the Plains States and isn't due exclusively to a Bermuda High or "heat ridge" as it is a transport of heat from the west, buoyed by a ridge of high pressure across the South.