Wednesday, February 22, 2012

Big Picture Vs. Little Details

Feb 22, 2012; 11:08 AM ET
Wednesday, 11:30 A.M.
It's all a matter of perspective today. On one of my radio Q & A's in Houston earlier today, the news anchor tossed it to me with a comment saying how tame the weather was today. And my response was that there are times when I like it tame, when the weather is boring, and it's very easy to forecast. Sometimes that's just nice to enjoy when you're in this business.
I perhaps should have responded in a somewhat different manner, by saying I prefer it when the weather is cut and dried. Sometimes the big ticket items behave well enough that forecasting them is not as big of a challenge as it might seem. The storms can be large, and they are easily trackable, and you have a good handle on how they will progress from one place to the next, as well as what precedes them and what follows.
In the grand scheme of things, the pattern we're in right now is relatively tame, or, more properly, relatively predictable. For instance, we know this is a very large area of the country enjoying a nice taste of spring today in terms of high temperatures, and that area extends from the eastern Rockies across the central and southern Plains to the East Coast. A strong cold front will erase that warmth from west to east (and south) between now and Friday night/Saturday morning. It's going to turn much colder to our north across Canada, especially the central and western Provinces of the country. And it's pretty easy to see that despite that area of growing cold, it will far less of an impact on areas from the middle Mississippi Valley and Midwest to the mid-Atlantic and New England. Yes, it will turn much cooler this weekend, but not below normal in most of the aforementioned areas. And there will be another storm in the pipeline that will send a 'lighter' surge of mild air into the Ohio and Tennessee Valleys into the East Monday into Tuesday.
That's the big picture. And you can see it when you look at snapshot images of the upper level charts. For instance, look at the one for tomorrow evening off the GFS ensembles
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There you can see the upper level ridge off the Southeast Coast, the deepening trough into the Mississippi Valley, and another system off the Northwest Coast. Now look at it for Sunday morning
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The chill comes and goes rather easily, and should have no trouble being replaced by some degree of warming.
This is all well and good, but it is the little details that can be frustrating or maddening, yet those are the very things that make or break a forecast. For instance, some of the modeling was suggesting there would be a lot of moisture around the Ohio Valley into portions of the mid-Atlantic, resulting in clouds and a few showers. To this point, it's been partly to mostly sunny in a lot of these areas, with temperatures steadily rising.
These little disturbances are not as easy to track. They tend to fall in the cracks, so to speak, and yet they have to be examined even more carefully in order to get the right result.
Similarly, a cold front charging through the Northwest into the Northern Rockies will mean rain, then lowering snow levels as a piece of colder air sneaks in behind the front. As this front drops through the central Rockies and out onto the Plains, it will generate some snow showers, but trying to figure out how much will fall in any one area will be likely trying to pin the tail on the donkey blindfolded.
Then as the front charges into the East, there can be some steadier rains (as well as snows if you're in parts of Upstate New York and northern New England) associated with a surface storm crossing the Lakes into New England. To the south, it would seem that the showers will fall apart on Friday, yet the 0z European model insisted on slowing the front, developing a wave on it, and bringing a much heavier rain event over the Appalachians into the East Friday and Friday night, that might even end in snow, especially across the interior!
Unfortunately, in the pattern we're in that is volatile, the model forecasts are going to have considerable differences between them, as well as from run to run. And even the ensemble forecasts that tend to even out some of the extremes that pop up in the operational runs, there can often be some significant differences.
It's a pattern that requires a steady hand and a cool head. I'm not sure I have either of those these days, but I'm going to try go back to my comfort zone and stick to the things I know. Today, that's not a lot, but tomorrow is a new day
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