WEATHER PERMITTING, A satellite launch scheduled for May 13 will help boost the accuracy of weather forecasts, says the National Oceanic & Atmospheric Administration. NOAA's new eye in the sky, dubbed NOAA-K, will be the first of five new "birds" with improved instruments that will not only do a better job of watching atmospheric goings-on but also provide more accurate data on snow cover and ocean temperatures.
The result, NOAA predicts, will be improved long-range forecasts--and, with the help of an enhanced meteorological computer model that went online in April, earlier alerts of potential floods, severe storms such as tornadoes, and clear-air turbulence. The lead time for flash-flood warnings has already more than doubled since 1994, to roughly 40 minutes. And today's five-day forecasts are far more accurate than the three-day forecasts of a decade ago, boasts NOAA's National Weather Service.
NOAA-K will orbit the earth every 102 minutes. From a relatively low perch of only 516 miles up, the $177 million satellite will beam down sharper images of cloud cover as well as snow, ice, and vegetation. It will also take temperature and humidity profiles of the atmosphere from sea level up to 24 miles, plus monitor dust and other particles in the air. After additional computing power comes online about 2001, NOAA expects a dramatic improvement in weather maps. Most of North America will be covered by a grid with 4-kilometer squares--down from the current 40-km grid--and maps of violent storms will have 1-km grids.