Daily Observations at Hyslop Exp. Stn., Corvallis
December 2004
Bold = new daily record set (old record, year)
| Day | Max Temp (F) | Min Temp (F) | Precip (in) | Snow (in) | 2 in soil Max | 2 in soil Min | 4 in soil Max | 4 in soil Min | Heating Deg. Days | Cooling Deg. Days | Growing Deg. Days | Evaporation (in.) |
| 1 | 48 | 39 | .18 | 0 | 48 | 42 | 46 | 41 | 21 | 0 | 0 | 0 |
| 2 | 50 | 30 | .02 | 0 | 52 | 40 | 48 | 43 | 25 | 0 | 0 | 0 |
| 3 | 38 | 33 | trace | 0 | 43 | 39 | 44 | 43 | 29 | 0 | 0 | 0 |
| 4 | 41 | 35 | 0 | 0 | 43 | 41 | 43 | 41 | 27 | 0 | 0 | 0 |
| 5 | 42 | 35 | .14 | 0 | 45 | 42 | 44 | 40 | 26 | 0 | 0 | 0 |
| 6 | 48 | 35 | .42 | 0 | 47 | 42 | 46 | 42 | 23 | 0 | 0 | 0 |
| 7 | 46 | 38 | .43 | 0 | 45 | 41 | 44 | 43 | 23 | 0 | 0 | 0 |
| 8 | 50 | 42 | 1.35 | 0 | 46 | 38 | 43 | 41 | 19 | 0 | 0 | 0 |
| 9 | 52 | 44 | .43 | 0 | 49 | 46 | 47 | 45 | 17 | 0 | 0 | 0 |
| 10 | 58 | 48 | .26 | 0 | 53 | 48 | 42 | 47 | 12 | 0 | 3 | 0 |
| 11 | 60 | 48 | .40 | 0 | 57 | 53 | 53 | 51 | 11 | 0 | 4 | 0 |
| 12 | 50 | 43 | .04 | 0 | 53 | 46 | 54 | 47 | 18 | 0 | 0 | 0 |
| 13 | 52 | 39 | .02 | 0 | 48 | 44 | 48 | 46 | 19 | 0 | 0 | 0 |
| 14 | 52 | 40 | .19 | 0 | 49 | 44 | 47 | 45 | 19 | 0 | 0 | 0 |
| 15 | 57 | 33 | .14 | 0 | 54 | 43 | 52 | 45 | 20 | 0 | 0 | 0 |
| 16 | 44 | 38 | .01 | 0 | 47 | 43 | 46 | 45 | 24 | 0 | 0 | 0 |
| 17 | 43 | 36 | trace | 0 | 47 | 44 | 47 | 44 | 25 | 0 | 0 | 0 |
| 18 | 46 | 35 | T | 0 | 48 | 43 | 46 | 44 | 24 | 0 | 0 | 0 |
| 19 | 52 | 35 | T | 0 | 51 | 44 | 48 | 42 | 21 | 0 | 0 | 0 |
| 20 | 51 | 32 | T | 0 | 49 | 47 | 47 | 43 | 23 | 0 | 0 | 0 |
| 21 | 48 | 27 | 0 | 0 | 48 | 37 | 45 | 40 | 27 | 0 | 0 | 0 |
| 22 | 41 | 30 | .11 | 0 | 41 | 37 | 42 | 39 | 29 | 0 | 0 | 0 |
| 23 | 48 | 38 | .01 | 0 | 49 | 41 | 46 | 42 | 22 | 0 | 0 | 0 |
| 24 | 44 | 33 | .01 | 0 | 48 | 42 | 46 | 43 | 26 | 0 | 0 | 0 |
| 25 | 40 | 34 | trace | 0 | 43 | 41 | 42 | 41 | 28 | 0 | 0 | 0 |
| 26 | 48 | 37 | .22 | 0 | 44 | 41 | 43 | 40 | 22 | 0 | 0 | 0 |
| 27 | 45 | 37 | .01 | 0 | 45 | 41 | 45 | 41 | 24 | 0 | 0 | 0 |
| 28 | 52 | 32 | 0 | 0 | 46 | 39 | 44 | 42 | 23 | 0 | 0 | 0 |
| 29 | 48 | 32 | .12 | 0 | 46 | 38 | 43 | 40 | 25 | 0 | 0 | 0 |
| 30 | 49 | 36 | .04 | 0 | 47 | 42 | 45 | 42 | 22 | 0 | 0 | 0 |
| 31 | 48 | 35 | .02 | 0 | 48 | 40 | 45 | 40 | 23 | 0 | 0 | 0 |
| Average/Total | 48.1 | 36.4 | 4.57 | 0.00 | 47.7 | 42.2 | 45.8 | 42.8 | 697 | 0 | 7 | 0.000 |
| Departure | 2.5 | 2.5 | -3.15 |   |   |   |   |   |   |   |   |   |