Jump in pressure value upon launch

It appears that the pressure sensor was jarred during launch and jumped readings from 
975.4 hPa at the surface to 950.2 hPa at the first sample after launch.  This results in 
erroneous altitude values throughout the sounding and erroneous ascent rate values during the 
first 30 seconds. The relative altitude calculations after the second sample should be 
correct.  Although the surface wind speed was recorded at 10.3 m/s, the next wind value is 
reported as 18.2 m/s - quite strong.  The bouncing of the balloon during the launch 
might account for the abnormal jarring of the sonde.

• Ascent rate(asc)
• Wind Speed(wspd)
• Relative Humidity (hybrid-b grid)(rh)
• Wind status(wstat)
• Retrieved pressure profile(pres)
• Dry Bulb Temperature(tdry)
• Dewpoint Temperature(dp)
• -180.0 - +180.0(alt)
• Wind Direction(deg)

• V wind component(v_wind)
• Wind status(wstat)
• -180.0 - +180.0(alt)
• Dewpoint Temperature(dp)
• Dry Bulb Temperature(tdry)
• Wind Direction(deg)
• Ascent rate(asc)
• Relative Humidity (hybrid-b grid)(rh)
• Wind Speed(wspd)
• Easterly Wind Component(u_wind)
• Retrieved pressure profile(pres)