Record rainfall and devastating mudslides on the West Coast; deadly tornadoes ripping across the Midwest; a crippling ice storm in the Northeast--yet still one of this country¹s mildest winters in decades. Not surprisingly, forecasters are predicting this summer to be one of the warmest and driest on record. How much of the weather over the past several months can be blamed solely on El Niño is open to debate, but it does remind us of just how basic weather is to all of us, everywhere. And though we¹ve yet to figure out how to actually prevent extreme weather conditions from forming, our ability to forecast and plan for them is improving tremendously.

Despite how erratic or random inclement weather often might seem to be, scientists are increasing their understanding of how atmospheric dynamics shape severe weather. More importantly, by using sophisticated computer and information technology systems, scientists are able to communicate basic meteorological data among users more quickly, ultimately keeping the public better informed. Because these instruments measure a variety of environmental conditions, their location is an essential part of how effective they are and how useful the data are for weather forecasting, emergency response, and day-to-day planning. In areas where the threat of potentially violent weather is a fact of life, such as Texas and the Midwest, a network of data-gathering instruments and rapid, on-line communication capabilities give both meteorologists and decision makers a powerful tool for working "smarter."

One of the more promising‹and the world¹s first‹statewide advanced meteorological instrument networks is the Oklahoma Mesonet, a collection of 114 measurement stations spaced strategically at an average of 35 kilometers throughout the state of Oklahoma. With at least one station sited in every county, each has a set of automated instruments located on or near a 10-meter tower collecting an array of critical real-time data every 5 minutes. All of the sites are instrumented to measure "core" parameters (e.g., air temperature, relative humidity, wind speed and direction, and barometric pressure) and "supplemental" parameters such as soil moisture and temperatures, leaf wetness, and air temperature and wind speed at heights higher than those measured as core parameters. The data are acquired, their quality verified, and then made available on line to customers in only 10­20 minutes.

Why the Mesoscale?

Meteorologists are interested in the mesoscale (ranging from a few kilometers to a few hundred kilometers) because severe weather events such as thunderstorms and squall lines typically take shape within this scale of the atmosphere. These events, and related severe weather episodes like tornadoes, flash floods, and the timing and duration of winter storms, are some of the hardest to predict, so accurate measurements of the meteorological factors controlling the formation of severe weather allow scientists to predict bad weather faster and more confidently.

This type of data has obvious advantages‹improved severe weather and flood warnings, more effective emergency management and disaster mitigation planning, enhanced fire control. But there are others who could benefit from mesoscale weather information: Cities dealing with air quality problems and regulatory compliance; farmers looking for the best time to plant, irrigate, apply crop controls, and harvest; aviation decision makers grappling with airspace-planning issues and terminal-area traffic management; and coastal and offshore industries concerned about the possibility of severe weather disrupting services, causing chemical/oil spills, or endangering workers. In other words, practically any weather-sensitive industry stands to gain.

Another significant user of mesonet data is electric utilities. Because commercial and residential electricity usage is intimately tied to various weather episodes, utilities can better serve their customers by 1) increasing operating efficiencies with improved forecast models for better load and generator scheduling and 2) identifying early on where repair crews should be deployed in preparation for storm-related power outages and faster restoration of service. And, with the deregulation of the utility industry looming, utilities will be looking for more ways to operate as profitably as possible. Mesonet data can help here as well, since utilities incur significant costs from running reserve power plants to meet peak demands. Accurate temperature, humidity, and wind measurements are key input factors in determining user-demands, as are precise 24-hour forecasts for planning day-to-day anticipated power requirements. One major U.S. electric utility estimates that better short-term temperature forecasts could save them over $8 million annually.

The Texas MesoNet

Convinced of the merits of the Oklahoma Mesonet, the Texas MesoNet Program is underway today in order to address the inadequacies of the state¹s current meteorological data-gathering systems. After all, Texas has the dubious distinction of recording the greatest number of tornadoes in the United States (the Category F5 tornado that struck the small town of Jarrell on May 27 last year killed 27 people in a matter of minutes). The state¹s thousands of dry creek beds and low water crossings, pounded by heavy localized rains, remain susceptible to periodic flash flooding‹more people die from flash floods in Texas than in any other state‹and its 600 miles of coastline leave millions vulnerable to hurricanes each year.

The Texas MesoNet Program is a joint effort involving the Texas Natural Resource Conservation Commission, Texas A&M and Texas Tech universities, electric utilities, the Public Utility Commission, and private industry. According to Texas A&M's Dr. Gary Sickler, Program Manager for the Texas MesoNet, the goal is "to have automated observing stations (similar to those in the Oklahoma system) in every county and at offshore sites into the Gulf of Mexico. If we had the funding and could get started today, we¹d have 250 new sites by the end of 2001‹that¹s about one site for every county in Texas--and a total of 600 new sites within five years of startup."

Of these stations, 65 would be augmented by lower atmosphere profilers and radio acoustic sounder systems (RASS) capable of measuring wind speed and direction from 100 to 5000 meters and virtual air temperature from 100 to 1500 meters. Measurements taken within these ranges allow for fine-scale predictive models for very localized weather forecasting‹for example, knowing what the weather will be at a specific recreational area.

Radian Electronic Systems, a part of Radian International LLC, is serving as technical advisor on the MesoNet Program. Because of our meteorological expertise (see sidebar) and a long history in developing, testing, and deploying advanced meteorological systems around the world‹especially atmosphere profilers and RASS--we are helping researchers evaluate wind profiler technology and equipment. To that end, in April 1998 we cosponsored, with Texas A&M, a symposium that examined the demand for improved severe weather forecasting and the role that the Texas MesoNet will play in addressing that demand.*

The need for accurate, timely meteorological data like those gathered by the Oklahoma Mesonet and the future Texas MesoNet, is as important to the urban planner in Sacramento as it is for the utility director in Schenectady--and for most industries in every state in between. Nebraska also has a mesonet system similar to Oklahoma's; other states have smaller scale systems that cover only a portion of the state. Owing to the measurement capabilities of radar profilers, however, only the Texas MesoNet will have the size and coverage of the upper atmosphere.

But as Mr. Russ Peterman, Radian Electronic Systems Manager, points out, "All of these diverse uses for this information are of course overshadowed by the savings in loss of life that can be realized through more accurate severe weather forecasting. To do good weather forecasting, we must have three things in place: an understanding of the science and dynamics of the atmosphere, the computing power to run processing-intensive numerical weather models, and spatially representative input data for the models. Atmospheric science and the computer industry have achieved the first two. The Texas MesoNet Program and our role in its development are making the third a reality. By moving forecasts down to the very local scales of value to emergency management agencies, we have the opportunity to reduce the loss of life from severe weather as never before."

*For more information about the Texas MesoNet Program, visit their Web site: http://www.met.tamu.edu/texnet/mesonet.html

This web site is maintained by Thomas John Petroski