THE OKLAHOMA MESONET: EVOLUTION FROM REAL-TIME

WEATHER NETWORK TOCLIMATE NETWORK

Christopher Fiebrich and Kevin A. KloeselOklahoma Climatological Survey

Norman, OK, USA

The Oklahoma Mesonet

• Commissioned in 1994• 120 stations• Report every 5 minutes• Over 4 billion observations

Primarily for Real-Time Weather

Data Quality is Top Priority

• Over 4 Billion high quality observations in the Mesonet archive– Every sensor calibrated before deployed to station

and re-calibrated at defined intervals– Every site visited 4 times annually on average for

site maintenance, sensor testing, and metadata updates

– Comprehensive automated and manual quality assurance

Extremes Measured in 2011

• Coldest Temperature Ever Recorded in State History– 10 February 2011– Nowata Mesonet station: -35 °C (-31 °F)– Reviewed by State Climate Extremes Committee of

the National Climate Data Center

Record Cold

Extremes Measured in 2011

• Highest Wind Gust Recorded in State History– 24 May 2011– El Reno Mesonet station: 67.4 m/s (151 mph)

Record Wind Gust

4:20 PM LT 4:25 PM LT

Extremes Measured in 2011

• Hottest Average Monthly Temperature for Any State and Any Month– July 2011– Statewide Average Temperature: 30.5 °C (86.9 °F)– Grandfield Mesonet site exceeded 37 °C (100 °F) on

101 days (old state record was 86 days)

Mesonet Inclusion in COOP

Mesonet Inclusion in COOP

• Mesonet data now included in official climate division average calculations

• Midnight-to-midnight observations from Mesonet eliminate the need for time of observation adjustments

Mesonet Continuity Sites

• Sensor Upgrades are Inevitable– Naturally ventilated to aspirated temperature

shelters in 2008– Relative humidity sensor (Vaisala HMP45) no

longer manufactured– Evaluation of new rain gauge models– Transition to thermocouple sensors for soil

temperature

Continuity Sites• 5 stations across the state selected– Minimal impact from anthropogenic sources– Minimal impact from wind obstructions– Minimal slope– History of very high data quality– High likelihood of long-term stability

• Will provide long-term (multiple years) overlap of old sensor and new model

Continuity Sites

Questions?