
Monthly Average Reference Evapotranspiration
The following are values of monthly average reference evapotranspiration (ETr) for each AgriMet station for the period of record. These ETr values are for the alfalfa reference crop (also known as "tall crop" reference). The ETr values were computed using the Kimberly-Penman 1982 procedure. Values during the winter months roughly approximate evaporation from bare (non-snow covered) wet soil, frozen or thawed. All of the AgriMet weather stations listed below are located in irrigated agricultural (or turfgrass) environments, and represent the ET conditions found in actively growing, irrigated cropland. Units are inches of water.
These values were computed by summing the average daily ETr for the month. Note that the values for February are based on the non-leap year - 28 day month.
Following the monthly values is a list of station names and the period of record used for computation of the monthly average ETr values.
Station Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total ABEI 0.60 1.07 2.77 4.51 6.87 8.16 9.65 8.66 5.77 3.21 1.32 0.56 53.15 AFTY 0.43 0.82 2.03 3.50 5.29 6.69 8.26 6.91 4.45 2.38 0.84 0.37 41.96 AGKO 0.65 1.23 2.80 4.24 6.48 7.91 9.03 7.42 4.95 2.73 1.05 0.57 49.06 AHTI 0.53 1.06 2.36 3.97 6.41 7.75 8.84 8.10 5.81 3.19 1.10 0.49 49.60 ARAO 0.57 1.09 2.06 3.37 5.06 6.10 7.72 6.17 4.03 1.92 0.79 0.53 39.41 BANO 0.83 1.25 2.15 3.04 4.24 4.69 5.20 4.48 3.39 2.17 1.01 0.72 33.19 BATO 0.74 1.31 2.66 4.05 6.04 7.40 9.17 7.66 5.08 2.61 1.09 0.53 48.35 BEWO 0.69 1.13 2.65 3.65 5.49 6.96 8.41 6.53 4.18 2.21 0.99 0.57 43.47 BKVO 0.44 1.02 2.51 4.03 5.78 6.94 8.88 7.50 4.96 2.55 0.98 0.41 45.98 BOII 0.56 1.14 2.56 3.96 5.95 7.39 8.68 7.00 4.29 2.28 0.94 0.55 45.31 BRKO 1.13 1.54 2.52 3.36 4.63 5.08 4.69 4.04 3.71 2.68 1.35 0.99 35.72 CEDC 0.95 1.52 3.14 4.45 6.50 8.29 9.89 8.59 5.87 3.53 1.54 0.89 55.16 CHAW 0.26 0.68 1.73 3.22 5.35 6.41 8.36 6.85 4.15 1.62 0.44 0.20 39.26 CHVO 0.83 1.37 2.78 4.12 6.11 7.80 9.30 7.92 5.23 3.01 1.22 0.71 50.40 COVM 0.60 1.05 2.34 3.76 5.52 6.54 8.13 6.50 4.24 2.50 1.22 0.79 43.19 CRSM 0.34 0.75 1.83 3.42 5.29 6.06 7.71 6.58 3.90 1.85 0.63 0.33 38.69 CRVO 0.64 1.24 2.27 3.47 5.29 6.48 8.70 7.56 5.22 2.48 0.84 0.51 44.69 DEFO 0.35 0.88 2.16 3.43 5.42 6.95 8.63 6.70 4.03 1.79 0.59 0.29 41.23 DRLM 0.73 1.13 2.62 3.98 5.78 6.65 9.07 7.50 4.76 2.58 1.19 0.57 46.55 ECHO 0.66 1.21 2.87 4.71 7.06 9.14 11.52 9.76 5.99 3.04 1.11 0.58 57.65 EURN 0.97 1.45 3.43 4.93 7.05 9.12 10.18 8.87 6.05 3.81 1.86 0.95 58.66 FAFI 0.50 1.01 2.34 4.14 6.30 7.56 9.24 8.17 5.73 3.31 1.14 0.47 49.93 FALN 1.09 1.89 3.98 5.50 7.91 9.93 10.78 8.80 6.13 3.53 1.75 1.05 62.35 FOGO 0.47 1.03 2.05 3.22 5.15 6.29 8.05 6.77 4.50 2.10 0.71 0.41 40.77 FTHI 0.70 1.20 2.93 4.45 6.57 7.74 9.43 9.00 6.12 3.39 1.42 0.62 53.56 GDVI 0.81 1.46 3.33 4.84 7.16 8.96 10.73 8.88 5.75 3.25 1.39 0.70 57.26 GERW 0.43 1.08 2.68 4.39 6.68 8.15 9.59 7.79 5.03 2.60 0.93 0.38 49.71 GFRI 0.83 1.50 3.31 4.76 7.26 9.33 11.74 10.19 6.78 3.90 1.55 0.71 61.86 GOLW 0.44 1.04 2.49 4.06 6.41 8.25 10.26 8.76 5.55 2.65 0.80 0.41 51.12 HERO 0.71 1.32 3.11 4.92 7.31 9.19 11.21 9.65 6.00 3.18 1.17 0.57 58.33 HOXO 0.44 0.94 2.19 3.69 5.81 7.23 8.58 7.17 4.57 2.07 0.63 0.37 43.68 HRFO 0.43 0.94 2.35 3.76 5.62 7.08 8.95 7.47 4.62 2.32 0.85 0.37 44.76 HRHW 0.56 1.22 3.00 4.73 6.99 8.56 9.81 8.10 5.52 2.91 1.08 0.45 52.93 HRMO 0.58 1.21 2.90 4.67 7.11 9.14 11.23 9.35 5.81 2.95 1.01 0.51 56.48 IMBO 0.76 1.22 2.48 3.87 5.63 6.93 9.24 7.92 5.00 2.60 1.11 0.65 47.43 KFLO 0.71 1.34 2.72 4.08 6.40 8.09 9.27 7.65 5.28 2.91 1.14 0.63 50.22 KTBI 0.43 0.93 2.63 4.54 7.21 8.45 10.59 9.67 6.48 3.57 1.30 0.44 56.24 LAKO 0.82 1.33 2.78 4.11 6.17 7.80 9.73 8.44 5.86 3.38 1.35 0.76 52.53 LEGW 0.73 1.30 3.07 4.91 7.16 8.71 9.98 8.52 5.47 2.87 1.14 0.59 54.44 LIDW 0.47 1.10 2.74 4.42 6.57 8.04 9.81 8.36 5.50 2.96 0.94 0.38 51.28 LORO 0.90 1.47 2.93 3.99 6.32 7.80 9.43 7.93 5.41 3.09 1.40 0.84 51.51 MALI 0.98 1.46 3.17 4.77 6.58 8.34 9.94 8.72 6.06 3.72 1.66 0.83 56.23 MASW 0.23 0.75 2.14 4.01 6.13 7.63 9.18 7.33 4.21 1.83 0.43 0.17 44.05 MDFO 0.64 1.26 2.39 3.75 5.87 7.65 9.24 7.68 5.14 2.61 0.90 0.53 47.66 MNTI 0.35 0.77 2.43 4.40 6.59 7.70 9.34 8.15 5.10 2.74 0.99 0.36 48.91 MRSO 0.82 1.27 2.80 4.20 6.23 8.00 9.91 8.71 5.88 3.07 1.25 0.63 52.77 NMPI 0.79 1.52 3.53 5.17 7.40 8.98 10.37 8.86 5.98 3.66 1.54 0.79 58.61 ODSW 0.42 1.06 2.72 4.47 6.66 8.30 10.45 9.20 6.01 3.15 0.93 0.39 53.76 OMAW 0.30 0.81 2.29 4.07 6.06 7.38 9.07 7.34 4.65 2.14 0.59 0.26 44.96 ONTO 0.55 1.21 3.11 4.98 7.48 9.07 10.94 9.32 6.11 3.40 1.21 0.59 57.95 PARO 0.41 0.93 2.14 3.55 5.40 6.81 8.38 6.83 4.30 1.97 0.65 0.34 41.70 PCYO 0.60 1.10 2.30 3.44 5.21 6.57 8.54 7.23 4.60 2.30 0.89 0.44 43.22 PICI 0.54 1.07 2.50 4.11 6.46 7.92 9.70 8.31 5.40 3.01 1.13 0.45 50.58 PMAI 0.63 1.29 3.17 4.93 7.22 8.55 9.84 8.30 5.50 3.17 1.26 0.66 54.52 PNGO 0.41 0.92 2.15 3.54 5.56 6.97 8.58 6.72 4.14 1.89 0.66 0.35 41.88 POBO 1.10 1.47 2.79 4.01 5.95 7.68 9.55 7.96 5.41 3.26 1.70 1.18 52.05 RDBM 0.35 0.78 1.99 3.45 5.20 5.99 7.57 6.03 3.60 1.76 0.60 0.33 37.64 RPTI 0.84 1.37 3.15 4.86 7.02 8.45 9.86 8.74 5.97 3.65 1.60 0.75 56.26 RTHI 0.55 0.89 1.91 3.52 5.52 6.13 8.20 7.14 4.83 2.29 0.77 0.45 42.19 RXGI 0.45 0.92 2.47 4.24 6.38 7.42 8.52 7.99 5.26 2.97 1.05 0.44 48.11 SIGM 0.55 0.89 2.11 3.44 5.36 6.34 8.74 7.30 4.27 2.05 0.82 0.54 42.40 TWFI 0.91 1.46 3.21 4.71 7.05 8.63 10.14 8.63 6.05 3.69 1.57 0.78 56.82 WRDO 0.77 1.44 2.95 4.21 6.32 7.59 8.45 7.43 5.11 2.88 1.16 0.67 48.98 ABEI Aberdeen, Idaho AgriMet Station Begin:1991 End: 2010 AFTY Afton, Wyoming AgriMet Station Begin:1987 End: 2010 AGKO Agency Lake, Oregon AgriMet Station Begin:2000 End: 2010 AHTI Ashton, Idaho AgriMet Station Begin:1987 End: 2010 ARAO Aurora, Oregon AgriMet Station Begin:1998 End: 2010 BANO Bandon, Oregon AgriMet Station Begin:1985 End: 2010 BATO Beatty, Oregon AgriMet Station Begin:2004 End: 2010 BEWO Bend, Oregon AgriMet Station Begin:2003 End: 2010 BKVO Baker Valley, Oregon AgriMet Station Begin:2001 End: 2010 BOII Boise, Idaho AgriMet Station Begin:1995 End: 2010 BRKO Brookings, Oregon AgriMet Station Begin:1999 End: 2010 CEDC Cedarville, California AgriMet Station Begin:1985 End: 2010 CHAW Chamokane, Washington AgriMet Station Begin:2007 End: 2010 CHVO Christmas Valley, Oregon AgriMet Station Begin:1985 End: 2010 COVM Corvallis, Montana AgriMet Station Begin:1986 End: 2010 CRSM Creston, Montana AgriMet Station Begin:1988 End: 2010 CRVO Corvallis, Oregon AgriMet Station Begin:1990 End: 2010 DEFO Dee Flat, Oregon AgriMet Station Begin:2003 End: 2010 DRLM Deer Lodge, Montana AgriMet Station Begin:1998 End: 2010 ECHO Echo, Oregon AgriMet Station Begin:1988 End: 2010 EURN Eureka, Nevada AgriMet Station Begin:2001 End: 2010 FAFI Fairfield, Idaho AgriMet Station Begin:1987 End: 2010 FALN Fallon, Nevada AgriMet Station Begin:2001 End: 2010 FOGO Forest Grove, Oregon AgriMet Station Begin:1991 End: 2010 FTHI Fort Hall, Idaho AgriMet Station Begin:1993 End: 2010 GDVI Grand View, Idaho AgriMet Station Begin:1993 End: 2010 GERW George, Washington AgriMet Station Begin:1986 End: 2010 GFRI Glenns Ferry, Idaho AgriMet Station Begin:1993 End: 2010 GOLW Goldendale, Washington AgriMet Station Begin:1991 End: 2010 HERO Hermiston, Oregon AgriMet Station Begin:1983 End: 2010 HOXO Hood River, Oregon AgriMet Station Begin:1987 End: 2010 HRFO Hereford, Oregon AgriMet Station Begin:1998 End: 2010 HRHW Harrah, Washington AgriMet Station Begin:1987 End: 2010 HRMO Hermiston (Harec), Oregon AgriMet Station Begin:1993 End: 2010 IMBO Imbler, Oregon AgriMet Station Begin:1994 End: 2010 KFLO Klamath Falls, Oregon AgriMet Station Begin:1999 End: 2010 KTBI Kettle Butte, Idaho AgriMet Station Begin:1996 End: 2010 LAKO Lakeview, Oregon AgriMet Station Begin:1988 End: 2010 LEGW Legrow, Washington AgriMet Station Begin:1986 End: 2010 LIDW Lind, Washington AgriMet Station Begin:1983 End: 2010 LORO Lorella, Oregon AgriMet Station Begin:2001 End: 2010 MALI Malta, Idaho AgriMet Station Begin:1983 End: 2010 MASW Manson, Washington AgriMet Station Begin:1994 End: 2010 MDFO Medford, Oregon AgriMet Station Begin:1989 End: 2010 MNTI Monteview, Idaho AgriMet Station Begin:1996 End: 2010 MRSO Madras, Oregon AgriMet Station Begin:1984 End: 2010 NMPI Nampi, Idaho AgriMet Station Begin:1996 End: 2010 ODSW Odessa, Washington AgriMet Station Begin:1984 End: 2010 OMAW Omak, Washington AgriMet Station Begin:1989 End: 2010 ONTO Ontario, Oregon AgriMet Station Begin:1992 End: 2010 PARO Parkdale, Oregon AgriMet Station Begin:1998 End: 2010 PCYO Prairie City, Oregon AgriMet Station Begin:1989 End: 2010 PICI Picabo, Idaho AgriMet Station Begin:1993 End: 2010 PMAI Parma, Idaho Agrimet Station Begin:1986 End: 2010 PNGO Pine Grove, Oregon Agrimet Station Begin:2003 End: 2010 POBO Powell Butte, Oregon AgriMet Station Begin:1993 End: 2010 RDBM Roundbutte, Montana AgriMet Station Begin:1989 End: 2010 RPTI Rupert, Idaho AgriMet Station Begin:1988 End: 2010 RTHI Rathdrum, ID AgriMet Station Begin:2008 End: 2010 RXGI Rexburg, Idaho AgriMet Station Begin:1987 End: 2010 SIGM St. Ignatius, Montana AgriMet Station Begin:1991 End: 2010 TWFI Twin Falls, Idaho AgriMet Station Begin:1990 End: 2010 WRDO Worden, Oregon AgriMet Station Begin:2000 End: 2010