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Sixteen years ago this isabel marant store week, nearly the entire eastern third of the nation was ravaged March 12-14, 1993, by a massive storm often called "The Storm of the Century" (20th century, that is). area. Since then, however, similar forecasting successes in the medium range (3-10 days in advance) have been few and far between, even with the tremendous advances in atmospheric science, forecast models and computer power.
The only decent snowstorm locally this winter, which generally dumped 5-8" across the area March 1-2, most certainly was not included in the "few and far between," as confidence isabel marant shoes in the potential for significant snow didn't really come until just a couple days before, and confidence was fluctuating even as the storm got underway.
The key to understanding the exceptionally accurate medium-range forecasts of the Superstorm was, in fact, its size. Larger-scale weather systems are intrinsically "easier" to forecast. Thus, for example, large winter storms are more predictable than, for example, a summer line of thunderstorms. And, the Superstorm -- to the best of my mulberry outlet knowledge -- was broader in areal extent than any other storm in recorded history.
In this regard, the measure relevant to the predictability of a weather system is its wavelength, or in other words the distance between the two high mulberry outlet uk pressure centers on either side (west and east) of the low-pressure center. The wavelength of the Superstorm was about 3,500 miles. In comparison, the wavelength of the storm here earlier this month was approximately 2,100 miles. Not unusually, in both cases buy isabel marant there were smaller-scale features (wavelength less than about 200 miles), such as snow bands and thunderstorms, embedded in the larger-scale circulations.
Recall from above that the Superstorm was not only predicted 5-6 days in advance, but done so with an unprecedented degree of confidence. There was skepticism in some quarters about this, including reluctance by many TV stations to buy into these early warnings; but, NWS stuck to its guns and proved correct. I, personally, played an important buy isabel marant role in this. At the time I was among those at the NWS National Centers for Environmental Prediction (NCEP) who was pioneering the development and applications of an operational ensemble prediction system (background here).
Ensemble forecasting involves a single model being run multiple (nowadays up to 50) times, each time with a set of slightly different initial conditions (temperatures, winds, pressure, etc.) in order to account for possible inaccuracies in the measured initial conditions. Each of these runs is known as an ensemble member, and together ensemble members provide a reasonably good portrayal of possible outcomes.
Although the system was still in its experimental phase in March 1993, output was made available to forecasters at NCEP's Hydrometeorological Prediction Center who provide guidance to all NWS local forecast offices. The long and short of this was that beginning 5-6 days in advance the ensembles consistently showed virtual unanimity amongst ensemble members in predicting the nature and severity of the impending Superstorm.
The rest is history with regard to the NWS's successful buy isabel marant sneakers forecasting of this particular storm, and more generally a recognition of the importance of continued development and use of ensemble prediction for assessing uncertainties and levels of confidence in all weather forecasts. This led a few years ago to NCEP implementing its operational Short Range Ensemble Forecast System.
ASIDE: Last Friday night Erin Burnett, a CNBC anchor, was on HBO's Real Time With Bill Maher. To add insult to injury, they kept Federal offices OPEN on the Monday after the storm, thus making us go to work! 1996 was a far superior storm for snow in my neighborhood.
The only high points were the recorded thundersnow on the tail end of the storm, and the record low barometric pressure of 28.50 I recorded here at my condo. Unlike most bonus snows, it remained cold for a rather extended period after the storm.
I found a black cricket this morning, my first of the season. That storm is a sore point for me because I MISSED it. I was in Florida at the time, after assuring myself before leaving DC that the storm wouldn't amount to much. I was totally besides myself the celine online next morning realizing I (along with everyone else) blew the forecast of what 'till then was THE BIg One. That storm was also huge in its coverage, and snow flurries in its wake, from mulberry factory outlet the cyclonic flow, were still being felt as long as celine handbags sale 5 days after it passed.
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