NSA/SONDE/C1 - Increased precision for alt, dp, pres, rh, tdry

The output precision of the following variables was increased 20060929:

   alt	changed from 1m to 0.1m
   dp	changed from 0.1degC to 0.01degC
   pres changed from 0.1 hPa to 0.01 hPa
   RH	changed from 1%RH to 0.01%RH
   tdry changed from .1degC to 0.01degC

Note that the increase in precision does not necessarily imply an increase
in accuracy.  Users are cautioned to continue to use their best scientific
judgement when using these or any other data.

• Relative humidity scaled, by total column amount from MWR(rh)
• Dry-Bulb Temperature(tdry)
• altitude above sea levelaltunits(alt)
• pressure at constant pressure surface(pres)
• Surface dew point temperature(dp)

NSA/METTWR/C1 - All data from 10m Level Missing

The winch that lowers the tower booms failed.  Manual testing of the motor and winch 
allowed the booms to be lowered briefly and then raised back into position.  A heavy freezing 
rain/icing event added extra weight to the booms.  This extra weight was suspected as the 
cause as to why the 10m boom became disconnected.  After a new motor was installed and 
all booms were lowered and re-raised the 10m level came back on line.

• 10m Average Calculated Dew Point(DP10M_AVG)
• 10m Average QLI Reference Temperature(RefT10m_AVG)
• Standard Deviation of 10m Calculated Vapor Pressure(VP10M_STD)
• 10m Average Relative Humidity(RH10M_AVG)
• 10m Vector Averaged Wind Speed(WS10M_U_WVT)
• 10m Average Calculated Vapor Pressure(VP10M_AVG)
• 10m Average QLI Input Voltage(Volt10M_AVG)
• Standard Deviation of 10m Vector Averaged Wind Direction(WD10M_SDU_WVT)
• 10m Average Temperature(T10M_AVG)
• Standard Deviation of 10m Relative Humidity(RH10M_STD)
• 10m Arithmetic Mean Wind Speed(WS10M_S_WVT)
• 10m Vector Averaged Wind Direction(WD10M_DU_WVT)
• Standard Deviation of 10m Calculated Dew Point(DP10M_STD)
• Standard Deviation of 10m Temperature(T10M_STD)

NSA/SONDE/C1 - Incorrect surface values of T and RH

The radiosonde was launched too quickly after being removed from the ground check set.  As 
a result, the system did not equilibrate with the local ground conditions and the 
automatically entered surface values are incorrect.

• Relative humidity scaled, by total column amount from MWR(rh)
• Dry-Bulb Temperature(tdry)
• Surface dew point temperature(dp)

NSA/METTWR/C1 - Missing CMH data

CMH data are missing.  Corrosion in the serial data line connections caused a loss of 
communication with the CMH.

• Chilled Mirror Calculated Vapor Pressure(VPCMH)
• Chilled Mirror Calculated Relative Humidity(CMHRH)
• Chilled Mirror Dew Point(CMHDP)
• Chilled Mirror Temperature(CMHTemp)
• Chilled Mirror Calculated Saturation Vapor Pressure(SatVPCMH)

NSA/METTWR/C1 - 10m level loss of power

The 10 meter instrument level lost power so all variables from this level are missing.

• 10m Average Calculated Dew Point(DP10M_AVG)
• 10m Average QLI Reference Temperature(RefT10m_AVG)
• Standard Deviation of 10m Calculated Vapor Pressure(VP10M_STD)
• 10m Average Relative Humidity(RH10M_AVG)
• 10m Vector Averaged Wind Speed(WS10M_U_WVT)
• 10m Average Calculated Vapor Pressure(VP10M_AVG)
• 10m Average QLI Input Voltage(Volt10M_AVG)
• Standard Deviation of 10m Vector Averaged Wind Direction(WD10M_SDU_WVT)
• 10m Average Temperature(T10M_AVG)
• Standard Deviation of 10m Relative Humidity(RH10M_STD)
• 10m Arithmetic Mean Wind Speed(WS10M_S_WVT)
• 10m Vector Averaged Wind Direction(WD10M_DU_WVT)
• Standard Deviation of 10m Calculated Dew Point(DP10M_STD)
• Standard Deviation of 10m Temperature(T10M_STD)

NSA/METTWR/C1 - 2m T/RH probe aspirator fan failed

The aspirator fan for the 2m level T/RH probe failed.  This caused higher than normal 
readings for temp and RH and artificially smoothed the data.

• 2m Average Calculated Vapor Pressure(VP2M_AVG)
• Standard Deviation of 2m Calculated Dew Point(DP2M_STD)
• Standard Deviation of 2m Relative Humidity(RH2M_STD)
• 2m Average Relative Humidity(RH2M_AVG)
• Standard Deviation of 2m Calculated Vapor Pressure(VP2M_STD)
• 2m Average Temperature(T2M_AVG)
• Standard Deviation of 2m Temperature(T2M_STD)
• 2m Average Calculated Dew Point(DP2M_AVG)

NSA/SONDE/C1 - RH sensor failure

It appears that one of the two RH sensors on this radiosonde was affected by ice after 
emerging from a low cold cloud.  As a result the reported RH values oscillate by about 10 
percent until the alternate heating cycle stops.  I suspect the lower value is more close 
to correct, but can't be absolutely sure.

• Relative humidity scaled, by total column amount from MWR(rh)
• Surface dew point temperature(dp)

NSA/METTWR/C1 - Wind direction sensor frozen

After a power outage the 40m wind direction sensor was frozen.  Data from this sensor was 
not representative of the true winds.

• 40m Vector Averaged Wind Direction(WD40M_DU_WVT)
• Standard Deviation of 40m Vector Averaged Wind Direction(WD40M_SDU_WVT)