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Prior to flight, a standard briefing should be obtained from the FSS. This briefing will contain the most recent weather information and data, and will serve either to verify information obtained through other sources, or validate the possibility of a go/no-go decision. It is also helpful to check one or more automated weather reporting sites, such as the Automatic Terminal Information Service (ATIS) or Automatic Weather Observing System (AWOS) that are close to the intended flying area. ATIS and AWOS provide the advantage of a real-time, immediate information source. They may be contacted by telephone, or often monitored by aviation radio. Phone numbers for the ATIS and AWOS systems may be found in the Airport/Facility Directory (A/FD). Radio frequencies for the ATIS and AWOS are shown on aviation sectional charts. 

Gathering weather information en route to the launch site can be done by searching for indications of current winds. For example, observe how the leaves on a tree move, track the smoke from a factory smokestack, or notice the direction a flag blows. All of these signs give good indications of the current winds, both on the ground and at low altitude. Once at the launch site, or possible launch site, most experienced pilots inflate and release a pibal (pilot balloon) to assess on site wind speeds and direction. [Figure 3-2] 

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Many pilots develop historical data on weather conditions in their home flying areas. When shared with the beginning pilot, this weather data provides a wealth of information on trends and cycles. The comparison of individual predictions with actual weather experienced offers understanding and insight into micro-area weather conditions. Comparison of weather reports from nearby weather reporting stations with the actual weather experienced is also be an excellent learning tool. This exercise provides insight into the weather patterns common in 

a particular flying area. See Appendix A for a sample weather briefing checklist that may be used as a guide to develop personal forms for recording weather briefings. 

There are numerous sources of weather information available on the Internet. These include but are not limited to web sites operated by the NWS (www.nws.noaa.gov), Intellicast (www. intellicast.com), and Unisys (www.weather.unisys.com). Web sites devoted to weather and ballooning include but are not limited to Blastvalve.com (www.blastvalve.com/weather), US Airnet.com (www.usairnet.com), and the Balloon Federation of America (BFA) at www.bfa.net. Ballooning enthusiast Ryan Carlton has developed a wind forecasting site that is located at ryancarlton.com/wind.php. All of these sites provide resources and reference information on weather. 

It should be remembered that none of these web sites provide an official weather briefing. It is necessary to call the FSS, or use an on-line briefing service such as Direct User Access Terminal System (DUATS) to receive an official briefing. Failure to receive a proper briefing may create a liability issue for a pilot in the event of an incident or accident. 

Some weather related tips are: 

• Forecasts are a good place to start, but are not the end of weather planning. Unforecast events happen continuously. Proficiency in understanding small area weather is necessary, and can only be developed with practice and experience. 

• Balloons generally fly early in the morning, within the first two hours after sunrise, to avoid unstable conditions, which may prove to be hazardous to balloon flights and operations. It may be possible to fly in the late afternoon, within an hour or two of sunset, when thermal effects are calming down and winds are usually decreasing. 

• Almost all balloon flying is done in relatively benign weather conditions and mild winds. Most pilots prefer to launch and fly in winds less than 7 knots. While balloon flying is performed in higher winds, pilots accept that the faster the winds, the more they are exposed to risk and injury. Balloon flight manuals list the maximum launch winds for a particular balloon; this information, as well as personal limitations, are considerations for any pilot. 

• Balloons do not fly in significant (or unstable) weather. A balloon should not be launched in the face of a squall line, or during a tornado warning or watch. 

• Flying in precipitation is a bad practice. Rainwater (or any frozen precipitation) on the balloon causes it 

