No snow total for BWI

Jim Lee, the meteorologist-in-charge at the NWS forecast office in Sterling, says a problem with snow measurements at BWI during the late departed snowstorm means we will not have an official total, perhaps for several days.

On top of that, he says, it's not yet clear how they will measure the four-day storm in February 2003 that currently holds title as the biggest on record for Baltimore.

One thing Lee says he is confident about is that this storm did beat the 2003 storm, by at least a fraction of an inch.

Here's the deal:

The contractor paid to make snow measurements at BWI for the weather service (the NWS has none of its own personnel there) evidently failed to follow NWS protocols in measuring the snow.

Those rules say the observer must allow snow to fall on an official "snow board" for six hours, then wipe it clear and repeat the procedure every six hours until the snow ends.

The technique is designed to split the difference between measuring all the snow at once (which means the snow will have compacted some from its own the weight), or measuring it more frequently, and perhaps exaggerating the snow depth by eliminating most compaction.

The contractor measured every hour on the hour and added it up. That produced a total of 28.6 inches. He also took a "snow depth" reading, meaning that he measured all the snow at once, after it stopped falling. Because of compaction, that came to 24.7 inches.

"We don't have an observation for every six hours," Lee said.

Sterling is now consulting with headquarters, and with climatologists, to figure out how to make a reasonable estimate of what a six-hour measurement might have been. "We'll have to come up with an official estimate somewhere between the 24.7 inch snow depth and 28.6," Lee said.

But then what should they compare it to? The No. 1 snowstorm currently on Sterling's Top Twenty list is the Feb. 15-18 storm in 2003. The total on the Sterling Web page for that storm was 28.2 inches.

Did the storm that buried my car (left) beat that? It's not clear.

The 28.2-inch measurement on the Sterling Web site notwithstanding, the National Climatic Data Center doesn't recognize four-day storms, Lee said. Besides, the 2003 storm was actually two storms. His office is now focusing on two days of that storm for the official record challenge. That's the total of 24.4 inches that fell on Feb. 16 and 17, 2003.

If that's upheld by the NCDC, both measurements from BWI for the Super Bowl Weekend Storm just ended would beat that mark, so whatever intermediate figure they eventually agree on would as well. And that would make this the biggest two-day storm on record for Baltimore.

Lee like its chances. "I'm feeling pretty comfortable saying we broke a two-day snowfall record in Baltimore," he said.

UPDATE: Preliminarily, the NWS is estimating the storm's two-day BWI total at 24.8 inches, beating the 2003 storm by 0.4 inch.

In the meantime, Sterling's Top Twenty Snowstorms chart was taken off the Website Saturday afternoon. The site still lists the February 2003 storm as the biggest THREE-day storm on record for the city at 26.8 inches. 

The biggest two-day storm, if downtown measurements are included, was in January 1922 - 26.3 inches. 

Stay tuned.

(SUN PHOTOS/Frank Roylance/The WeatherDeck (top)/My poor car (bottom))

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