Daily Observations at Hyslop Exp. Stn., Corvallis
September 2004
Bold = new daily record set (old record, year)
| Day | Max Temp (F) | Min Temp (F) | Precip (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 | 91 | 57 | 0 | 96 | 65 | 88 | 68 | 0 | 9 | 24 | .377 |
| 2 | 74 | 50 | T | 85 | 64 | 79 | 68 | 3 | 0 | 12 | .112 |
| 3 | 69 | 48 | .25 | 77 | 60 | 72 | 64 | 6 | 0 | 9 | .104 |
| 4 | 76 | 51 | T | 85 | 60 | 77 | 61 | 1 | 0 | 14 | .201 |
| 5 | 73 | 49 | 0 | 80 | 60 | 74 | 64 | 4 | 0 | 11 | .152 |
| 6 | 77 | 48 | 0 | 88 | 60 | 80 | 62 | 2 | 0 | 13 | .253 |
| 7 | 81 | 50 | 0 | 91 | 59 | 83 | 62 | 0 | 1 | 16 | .242 |
| 8 | 81 | 46 | 0 | 93 | 62 | 84 | 65 | 1 | 0 | 14 | .214 |
| 9 | 78 | 50 | 0 | 93 | 62 | 84 | 65 | 1 | 0 | 14 | .239 |
| 10 | 70 | 47 | 0 | 78 | 61 | 74 | 65 | 6 | 0 | 9 | .110 |
| 11 | 82 | 50 | .05 | 90 | 62 | 80 | 63 | 0 | 1 | 16 | .199 |
| 12 | 72 | 52 | .01 | 80 | 64 | 75 | 66 | 3 | 0 | 12 | .107 |
| 13 | 70 | 53 | .20 | 79 | 62 | 73 | 64 | 3 | 0 | 12 | .071 |
| 14 | 70 | 48 | .08 | 78 | 58 | 72 | 62 | 6 | 0 | 9 | .155 |
| 15 | 74 | 52 | .06 | 82 | 58 | 74 | 61 | 2 | 0 | 13 | .147 |
| 16 | 72 | 48 | .02 | 74 | 59 | 70 | 62 | 5 | 0 | 10 | .124 |
| 17 | 69 | 53 | .38 | 74 | 59 | 69 | 60 | 4 | 0 | 11 | .076 |
| 18 | 65 | 48 | .57 | 70 | 56 | 67 | 58 | 8 | 0 | 7 | .109 |
| 19 | 57 | 47 | .58 | 58 | 55 | 58 | 56 | 13 | 0 | 2 | .080 |
| 20 | 60 | 42 | .19 | 67 | 54 | 62 | 56 | 14 | 0 | 1 | .002 |
| 21 | 68 | 41 | .01 | 75 | 54 | 68 | 55 | 10 | 0 | 5 | .154 |
| 22 | 69 | 44 | 0 | 74 | 54 | 68 | 57 | 8 | 0 | 7 | .158 |
| 23 | 72 | 46 | 0 | 74 | 53 | 67 | 56 | 6 | 0 | 9 | .148 |
| 24 | 75 | 49 | 0 | 77 | 56 | 71 | 57 | 3 | 0 | 12 | .100 |
| 25 | 76 | 50 | T | 80 | 58 | 70 | 58 | 2 | 0 | 13 | .252 |
| 26 | 72 | 50 | .01 | 76 | 58 | 69 | 56 | 4 | 0 | 11 | .120 |
| 27 | 72 | 51 | T | 76 | 58 | 70 | 61 | 3 | 0 | 12 | .167 |
| 28 | 79 | 49 | 0 | 77 | 58 | 71 | 59 | 1 | 0 | 14 | .142 |
| 29 | 80 | 50 | 0 | 80 | 58 | 73 | 60 | 0 | 0 | 15 | .135 |
| 30 | 66 | 49 | .01 | 73 | 59 | 68 | 61 | 7 | 0 | 8 | .115 |
| Average/Total | 73.0 | 48.9 | 2.42 | 79.3 | 58.9 | 73.0 | 61.1 | 126 | 11 | 335 | 4.565 |
| Departure | -2.4 | 1.1 | 0.91 |   |   |   |   |   |   |   |   |