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. 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. 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] Some weather related tips are: 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  •  Flying in precipitation is a bad practice. Rainwater  (or any frozen precipitation) on the balloon causes it  •  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.  •  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 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.  •  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.  $_{Figure 3-2.}$  Preparing to release a pibal. 3-3