NSA/METTWR/C1 - PWS data missing due to blizzard

PWS was offline and data was missing.  A blizzard consisting of heavy wet snow and strong 
winds caused snow impaction in the optics.  The PWS reported missing data as it was 
unable to measure anything meaningful.

• 1 hour Present Weather Code(PwCod1hr)
• Precipitation Rate(PcpRate)
• 1 minute Average Visibility(AvgVis1mi)
• 15 minute Present Weather Code(PwCod15mi)
• Cumulative Snow Sum(CumSnow)
• Present Weather Sensor Alarm(PWSAlarm)
• Instant Present Weather Code(InstPwCod)
• 10 minute Average Visibility(AvgVis10m)