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Monday, February 07, 2011

Weather-tainment !

Either the film The Day After Tomorrow... or Chicago's Lakeshore Drive


There should be a  W! channel on cable for The Weather-tainment Channel.. For years the weather report has been a gotcha! that has been orchestrated to get people to tune into the news. As a result, we see the same overemphasis on bad weather news just as we see violent and nasty events sensationalized

Since peoples' lives could depend on it, you would think that the weather people on cable tv would make an effort to believable. Some of the trouble in Chicago may have happened because we have come to expect over-the-top weather forecasts. On February 1, I was talking to my brother, and I said that one has to take the forecasted amount of snow, cut it in half, then add 10 to 20% for an accurate prediction: the TV forecast 10 inches to 15 inches of snow, we had 5 1/2 inches, maybe 7 inches nearby;  half of 10 inches is 5, and half of 15 is 7 1/2 inches. Spot on.

I use Unisys and Weather Underground for their weather models to see future weather. In fact, Weather Underground's GFS model had the February 2 storm on its forecast at least a week before, because I remember looking at it on Wednesday, January 26, 2011 as I was trying to determine whether I should meet my brother in Port Huron - sixty miles away - in the first week or second week of February.
http://weather.unisys.com/
http://www.wunderground.com/

At Unisys, there is a link to their NAM model on the homepage. At Weather Undergroun you will have to look under "Maps & Radar" and then "Models".  (Keep in mind precipitation amounts are usually for rain, so for snow, multiply by 10.)
There will be some work involved here. This will require some reading and study, but it is worth it. I used to rely on Unisys, and the results were not only always dependable, they were sometimes hard to believe. When I had to drive 100 miles, there was a big difference between driving in 1 to 3 inches of snow and 4 to 6 inches of snow; the first is doable, the second might not be - a lot depends on the snow removal habits of the municipalities you are driving through... for me, it was Macomb County and St. Clair County mainly, and throughout 35 years, Macomb County hit the expressways first thing in the morning, while St. Clair County got the surface roads, and left the expressway until later. So 5 inches of snow could leave me with a clear shot into St. Clair County where I might come to an abrupt halt.
Unisys said 1 to 3, we had 2... it never let me down. Once there was a blue speck on an NAM 24 hour forecast I missed at first glance. We were doing a night job the next day. The blue dot indicated a storm of such a small size I could only think it was a glitch.
However, next day at 6:20 PM EDT for 20 minutes a storm about 3 miles wide came through for 20 minutes: wind, rain, hail; then sun like nothing had happened! I was quite impressed!

So, on February 1, I looked at Unisys, Weather Underground, and the NOAA and a couple others: no weather model showed anything near the amount of snow the Detroit TV stations were busy touting. They showed a lot in Chicago, Indiana, and Ohio,  but not in Michigan, where there seemed to be 7 1/2 inches maximum.
We had 5 1/2 inches on the 2nd. The Detroit stations had to strain to find localities that had anything near the lower limits of what they forecast.

What have I learned from all this? Jet streams, man. They steer the storms. It all jet streams - winds at the height of 300 millibar pressure approximately.The same jet streams that pushed the hurricanes of 2010 to stay in the Atlantic push the snow to the east coast; on February 2, the streams were bowing northwards toward us. 

(If you're interested and need help, perhaps a longer post with some help learning how to use these maps and forecasts could be in order. Let me know.)

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