Weather Metadata

Instrumentation histories are accurate to the best of our knowledge, but not necessarily complete.

Air Temperature & Relative Humidity


  • Vaisala HMP155A measures air temperature and relative humidity ( With a 41005-5 14 plate radiation shield (

Height: 3 and 5 m

06/06/18: swapped with calibrated sensors

05/01/17: swapped with calibrated sensors

06/08/16: swapped with calibrated sensors

08/28/14.Installed: 3m and 5m


  • Vaisala HMP45C measured air temperature and relative humidity (

Height: 5m

08/28/15 swapped with calibrates sensor

05/2013: swapped with calibrated sensor

08/08/11: swapped with calibrated sensor

08/28/09: swapped with calibrated sensor

08/19/08: Installed

  • R.M. Young 41382VC measured air temperature and relative humidity (

Height 3m

04/18/12: Swapped with calibrated sensor  (measures in Celsius)

08/08/11: Swapped 3m with calibrated sensor (measures in Fahrenheit- converted to C in logger program)

08/19/08: Installed

  • CS500 measured air temperature and relative humidity (

Height 5m

08/19/08: removed

  • 1m Temp/RH removed 08/19/08



  • OTT Pluvio 2 measures "year round precipitation" ( Surrounded by a double fence Wyoming wind shield.

performed guided accuracy test: 8/23/16

not working: to 6/8/16-8/23/16. Our summer tipping bucket was able to cover that outage, however two snow events occurred during the outage of the year-round gauge, the timing and volume of these events were likely not measured accurately by the tipping bucket.

Installed: 08/18/10

  • TE525WS measures "rainfall- tipping bucket" ( Surrounded by a single alter shield 

Checked level: 06/06/18

2016: Snow events occurred on June 5th, 8th, and 21st. The exact timing and volume of these events were not measured accurately.

Calibrated: 06/09/16


  • OTT Pluvio 250 mm with ring heater removed
09/22/12 - 05/04/13(this date could be wrong): reinstalled
08/18/10: removed



  • R.M. Young 5106 measures wind speed and direction. (

Note: During winter the sensors are affected by rime ice that prohibits the propellers from spinning at low wind speeds.  Rime can only build up when there is very little wind, so it is difficult to know if they are reporting low or zero wind speeds due to ice or actual conditions.  However, a best attempt was made to replace steady zero values with NAN.

Height: 5 m

2016 data comes from the R.M. Young 5103 because it provides a more complete data-set. Readings from the instruments are nearly identical. 

06/08/16: swapped new 5108-45 for the 5106. crossarm was out of level, now level and more secure

Installed: 06/02/15 new.  (an R.M. Young 5103 was installed at the same time also at 5 m. Its data is available upon request but for 2015 is not output through this website)


  • Met One 024A measures wind direction and Met One 014A measures wind speed (

Height: 5m

06/02/2015: both removed

08/28/14: WS and direction sensors swapped with calibrated sensors

08/28/13: WS and direction swapped with calibrated sensors

07/23/13: moved WS and direction sensors to new tower

05/2013: WS and direction sensor swapped with calibrated sensors

08/08/11: WS and direction sensors swapped with calibrated sensors

08/19/08: WS and direction sensors swapped with calibrated sensors

  • 1m WS removed 08/19/08

Soil Temperature

AM25T Thermocouple multiplexer ( with 18 connected omega engeinnering thermocouples

Evaporation Pan


  • Novalynx 255-100 measures evaporation pan depth (

06/06/18: Evap pan and gage set up, leveled and calibrated for the season


  • Novalynx 255-200 evaporation pan (

09/27/07: flipped pan upside down. it was already filled with ice

PAR Sensors


  • LICOR Quantum LI-190SB measures terrestrial PAR ( There is no heater/ventilator on the PAR sensor, which means data following new snow is inaccurate. If you would like to find and remove that data, we suggest noting the times when there is a large offset between the PAR data to the total solar radiation data.

Height: 1.80 m above ground surface

06/06/18: leveled

06/05/17: leveled

06/09/16: swapped with calibrated sensor

07/23/13: swapped with calibrated sensor

05/2013: swapped with calibrated sensor

08/06/2011: swapped with calibrated sensor

08/29/09: swapped with calibrated sensor

Height before 5/16/2013: 1.78 m

  • LICOR Underwater Quantum LI-192SB measures Lake PAR (

Height: 1.3m below surface on 8/26/16- anchored to bottom so height below surface will vary

8/05/17: Sensor failure for remainder of season

8/23/16: swapped with calibrated sensor

summers '13,'14,'15,'16 sensor not cleaned of algal growth, affecting measurements.  The increase in lake PAR levels immediately following the sensor swap on 8/23/16 is likely due to the sensor being free of algae.

07/23/2013: installed


08/13/07: lowered underwater par from 1.3 to 1.8m

06/14/10 cleaned underwater par

08/12/07: cleaned underwater par of algal growth

UV Sensors


  • Yankee Environmental Systems UVA-1 and UVB-1 measure UVA and UVB radiation (

06/06/18: leveled both sensors, oriented E to W

08/31/17: leveled both sensors

03/25/16: swapped both sensors with calibrated sensors

04/19/09: Installed (wiring fixed so logging begins 07/1/2010)

Other Radiation


  • Delta-T Devices BF5 Sunshine Sensor measures total and diffuse solar radiation ( The BF5 heater/ventilator unit is not as good as the CMP6 or CNR4.  Snow covered periods have been removed.

06/06/18: installed

06/04/17: installed -- 09/23/17: removed

  • Kipp & Zonen CMP6 measures "solar radiation" ( With CVP2 power adapter (?). 

06/06/18: leveled, oriented N-S

06/03/17: leveled

08/19/08: Installed

  • Kipp & Zonen CNR4 measures longwave and shortwave looking up and looking down (  Negative shortwave values at night are an instrument artifact. In order to maintain consistency with historic data, they are left in the record.

10/01/2018: repaired ventilation fan, unsure how long it was broken, was working in mid-Aug 2018.

06/06/18: leveled sensor, oriented N-S

06/07/17: leveled sensor

06/09/16: swapped with calibrated sensor

05/13/13: Installed


  • LICOR Pyranometer LI-200SA measures "Solar Radiation" (

08/19/08: removed

04/30/07: installed

Lake Sensors


  • CS 107 measures lake temperature (
Height: 2m below surface on 8/26/16 - anchored to bottom so height below surface will vary

09/23/17 Sensor moved by 4 cm
07/29/17: Sensor moved by 27 cm
08/28/09: Installed/replaced
08/19/08: Installed 
  • CS420 measures lake depth (

Height: 2m below surface on 8/26/16 - anchored to bottom so height below surface will vary

08/13/07: put transducer in pipe


Pressure reported here is uncorrected for sea level. Add 85 millibar to correct for sea level.


  • CS106 Vaisala PTB110 measures Barometric Pressue (

06/09/16: Installed.


  • CS100 Serta 278 measures Barometric Pressure (
06/09/16: removed
  • CS105 Vaisala PTB101B measures Barometric Pressure (

Snow Depth


SR50A measures snow depth ( The snow depth sensor cannot always detect early small quantities of snow that do not completely cover the vegetation. Therefore early snow events may not be recorded here. Check the webcam or calculate the albedo for information on the discontinuous snow season.

Snow depth data can be noisy due to blowing snow or very low density snow.  In order to produce the 3 hour data, we took samples every 5 minutes.  We wrote a script that removed instances where there was more than a 1.0 cm of change in 5m, or if there was a grater than 0.5 cm change at the same time as a bad quality number from the instrument.  Once a data point was removed, the filter was stricter for immediately following measurements to be included.  We also manually corrected a handful of points. We then filled in the removed 5 minute points through linear interpolation and applied a 3 hour moving average.

06/06/18: changed programing to hourly 'burst mode with median value'

9/22/2017: replaced transducer

8/26/2016: replaced transducer

8/23/2015: replaced transducer

5/16/2013: installed (possibly incorrectly programed at beginning so data table not storing)



CR3000 (, RF450 pair (, NL100 (

Note that raw logger files record midnight as 00:00:00 of the following day, while the website's database converts midnight to 24:00:00 of the current day.  If you are comparing data downloaded from the website to a raw data file, you may need to convert one of your data sets.

06/06/2018: updated OS from std.6 to std.31.03, changed main scan rate from 60 to 30 secs, updated program


CR10x (, old radios

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