WEATHER CHECKLIST FOR XC
- winds aloft
- winds aloft from current soundings
- surface winds (mesonet)
- wind forecast
- look outside
- 5 day forecast
- barometric pressure (ideal is 29.90 to 30.10)
- instability index
- height of the -3
- top of the lift (sometimes 1 to 3000’ above predicted)
- first useable lift time
- maximum lift (often greater than predicted)
- position of lows and highs
- pre and post frontal and when
- K index (possibility of thunderstorms) 10% can be good
- moisture content of ground and air
- night to day temperature spread (30 degrees is ideal)
- check with other pilots to see what they think
- watch the sky and wind for changes before and after launch
- where is the jetstream
- check internal conditions
- which site to fly
- feel of cycles and wind on launch
- speed, strength and size of cloud development
- base wind below 8 mph at launch