Visible satellite loop of Hurricane Irene impacting the D.C. area while spinning off the mid-Atlantic Coast

Hurricane Irene caused extensive damage (amounting to perhaps around $10 billion) and loss of life (in the tens of people) after making landfall in North Carolina on August 27 as a category 1 storm. Though much discussion is already underway about whether or not Irene was “overhyped,” particularly in the New York City area, there is little denying this was a rare event for much of the coast north of North Carolina. In D.C., the effects were relatively minor, though still rather significant for a tropical system in this area. National Airport recorded a gust to 60 mph and had one hourly observation of sustained winds to tropical storm force. The daily rainfall in D.C. on the 27th was the highest August daily total in 4o years (since the similarly tracked Tropical Storm Doria) and the 3.83″ total helped boost D.C. to its wettest August in a long while. At its peak, several hundred thousand locally (and north of 5 million on the East Coast) were left without power after a number of trees (among other items) fell and toppled power lines.

100 degree days at Washington, D.C., Baltimore, Md. and Dulles, Va.: Averages, extremes and what to look for

This article has been updated to cover all 100F+ readings observed through August 1, 2011 when National Airport hit 100F and the other locations remained in the upper 90s.

While the Washington, D.C. to Baltimore, Md. area averages about one 100-degree day each year, it is not a super common occurrence, and stretches of years without them are — or, someday, where? — to be expected. Yearly numbers and a few other facts for both Washington and Baltimore follow, as does a quick look at the atmospheric setup for the area’s most extreme of extreme heat.

Washington, D.C. averages 1.2 days of 100F+ or above as of the 1981-2010 climate period. The long-term average is less than one day per year, with 109 days (including five so far in 2011) at D.C. that have hit or topped 100F. The highest temperature ever at D.C. was 106F, and it was reached on August 6, 1918 and July 20, 1930. A breakdown of all days 100F+ at D.C. is heavily skewed toward the lowest numbers. 44% hit 100 on the nose, 22% made it to 101, 17% to 102, 7% to 103, %6 to 104 and 2% each to 105F and 106F. The most recent “super heat” temperature came on July 29, 2011 when D.C. reached 104F, the highest temperature observed there in over a decade and tied for 5th hottest all time.

July 19-22, 1930 make up the longest string of days 100F+ in Washington at four, also featuring the hottest temperature on record. Washington has dealt with three other 100F+ streaks of three days, most recently in 1993. The most 100-degree days in any year was 11 in 1930, when two major streaks of 100F+ lasted for the record four days and three days (with a two day break in between) each. For 10 years in a row, in 1888 through 1897, no 100 degree or higher readings were recorded at Washington. The longest streak of sub-100F years in recent times was the seven years from 1970 through 1976.

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Washington, D.C. thunderstorm days: Examining the last 30 years of data

In the July installment of a year-long series of D.C. climatology posts on Capital Weather Gang, I included a graphic showing the averages for thunderstorm days by month in Washington over the last 30 years. Why 30 years? That’s the National Climatic Data Center standard for climate normals, and they just released a new set. This information, however, comes from additional research through daily records posted on the Weather Underground.

Thus far, I have only looked at the last 30 years, but may build back as far as I can at some point. Either way, this post will be updated at least a bit with data already obtained, but see below for some of it for now:

D.C. averages 32.8 thunderstorm days per year. 18.8 occur during meteorological summer (June-August). July is barely the statistical winner, though for real purposes it is tied with June for the most thunderstorm days per year. The curve is almost surprisingly normal, with a quicker drop off in fall than rise in spring thanks to lacking upper-level cold air of the winter prior that gives spring an extra boost in both storms and severity of storms.

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Fourth of July fireworks in Washington, D.C.

The 4th of July is coming, and it’s perhaps the best time of year to be a D.C. resident. This will be my sixth Independence Day in the city — I’ve taken photos of the fireworks show the last three years. It looked like I might not make it out this year, but plans have shifted, so it seems I will indeed get to add to my photo collection. While I think about where to set up for 2011, I figured I might as well share some shots from 2008-2010 as well as links to fuller sets.

2008 – From the Marine Corps War Memorial

2009 – From the Netherlands Carillon

2010 – From the banks of the Potomac River

Sets on flickr: 2008 | 2009 | 2010
Photo posts on 2008 | 2009 | 2010

My introduction to moviemaking

I’ve been meaning to have a video camera better than that attached to my iPhone for some time, and a May storm chasing expedition seemed like a good reason to make that purchase. So, check out my short and probably poorly edited first “movie” of Rock Creek Park in Washington, D.C. — cameo by Dupont Circle.

Select an HD option for highest resolution…

While the HD produced by this camera (Sony HDR-CX110) is not quite what a DSLR or other high-level HD camera might, it’s pretty good for the price and has solid dynamic range coverage.

The Flickr “top 5″, April 2011 edition

I don’t post enough photos, and I don’t use Flickr enough. It is a cool site though, great way to get easy exposure. Of the 490 images currently uploaded at Flickr (about 1/4 snowstorm related), these are the top 5 “most interesting” (whatever that means) as of April 2011.