Now
Mixed precipitation showers, cold. Some leftover moisture and energy from yesterday's non-event was being swept over the Washington metro area today ahead of a cold front moving eastward from the Ohio Valley. Showers of mixed precipitation type were falling through temperatures mainly in the mid and upper 30s. The next Arctic attack, now massing on the Canadian border, will sweep into the area over the weekend, setting the stage for what promises to be the most frigid week of the season so far.Tonight and Tomorrow
For the outlook through the rest of the weekend, scroll on down to Camden's post below.
Climate Corner
The release of the first volume of the IPCC Fourth Assessment Report this morning was widely covered in the world press. Among at least 1000 others, articles appeared online in the WaPo, NYT, ChiSunTimes, BoGlo, USAT, and Miami Herald. The package of articles at the UK Guardian was especially comprehensive. A pdf file (about 2.3MB) of the report and the webcast of the announcement are available online. RealClimate.org has started a thread for discussion of the report.Bob Ryan had a short, but effective, interview on the subject last night with Ralph Cicerone, who is President of the National Academy of Sciences here in Washington. Imagine that: a broadcast meteorologist actually consulting a real climate scientist, an "atmospheric scientist whose research in atmospheric chemistry and climate change has involved him in shaping science and environmental policy", instead of promoting radical right radio rhetoric. One of Dr. Cicerone's comments should be listened to carefully by Bob's more paranoid broadcast brethren: There will still be jobs for operational forecasters, even with global warming!
The belief tanks, of course, have geared up for attack mode in response. If you want to keep score at home, the droll Prof. Rabett has devised a version of Global Climate Denialist Bingo. Get 4 hits in a row and win a prize! In addition to his political role, Benjamin Franklin was one of the founders of American scientific meteorology, so it's only fitting that the denialists are putting their money where their mouths are and offering 100 Benjies for attacking the IPCC.
Cloudy, cold. "Do your homework, boys and girls." (Bob Ryan, 11pm last night) Fortunately or frustratingly, depending on your position on the Washington snow spectrum, light snow slid off to the east today south of a line from just south of Charlottesville to near Ocean City. The precipitation was associated with an Atlantic coastal front northeast of a weak low pressure area having trouble getting organized along the Gulf coast. This low is expected to develop more off the Carolina coast tonight, taking the main body of precipitation away with it south and east of the Beltway.
Not a lot has changed since Dan's early afternoon update, so I won't repeat his post. The latest models have continued to support the notion of a storm track suppressed to the south of the Mid Atlantic area. Although there are some differences in the intensity of the storm development, both major U.S. models keep the heaviest precipitation from central and southeastern Virginia southward, where it would be mostly in liquid form. At this point, the observed storm system is extremely weak, and the models don't provide a lot of upper air energy support, so any major development is likely to take place well offshore, after precipitation has ended in this area. We're adjusting our snow accumulation potential chart to reflect the likelihood of lower amounts.
Sunny, cold. A weak low pressure wave which gave some scattered snow flurries to the region yesterday, mainly to the east of the metro area, deepened rapidly well offshore to help pump in colder temperatures today. Readings struggled to reach freezing in most locations with a brisk northwesterly breeze; highs were 33° at National, 32° at Dulles, 31° at BWI.



