Daily Observations at Hyslop Exp. Stn., Corvallis
August 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 | 86 | 51 | 0 | 105 | 73 | 97 | 76 | 0 | 4 | 19 | .280 |
| 2 | 88 | 48 | 0 | 105 | 72 | 97 | 76 | 0 | 3 | 18 | .341 |
| 3 | 82 | 48 | 0 | 103 | 71 | 95 | 76 | 0 | 0 | 15 | .231 |
| 4 | 83 | 57 | 0 | 103 | 71 | 93 | 74 | 0 | 5 | 20 | .148 |
| 5 | 72 | 54 | T | 91 | 71 | 85 | 74 | 2 | 0 | 13 | .310 |
| 6 | 78 | 55 | .10 | 98 | 71 | 91 | 73 | 0 | 2 | 17 | .216 |
| 7 | 73 | 48 | .02 | 87 | 64 | 80 | 68 | 4 | 0 | 11 | .178 |
| 8 | 82 | 48 | 0 | 98 | 64 | 90 | 68 | 0 | 0 | 15 | .351 |
| 9 | 95 | 58 | 0 | 102 | 68 | 93 | 72 | 0 | 12 | 27 | .480 |
| 10 | 99 | 49 | 0 | 108 | 71 | 98 | 76 | 0 | 9 | 24 | .458 |
| 11 | 94 | 54 | 0 | 104 | 71 | 96 | 74 | 0 | 9 | 24 | .359 |
| 12 | 96 | 53 | 0 | 105 | 73 | 97 | 76 | 0 | 10 | 25 | .274 |
| 13 | 93 | 53 | 0 | 106 | 74 | 98 | 77 | 0 | 8 | 23 | .430 |
| 14 | 92 | 56 | 0 | 104 | 74 | 95 | 76 | 0 | 9 | 24 | .302 |
| 15 | 92 | 54 | 0 | 108 | 75 | 96 | 77 | 0 | 8 | 23 | .248 |
| 16 | 86 | 50 | 0 | 103 | 72 | 96 | 76 | 0 | 3 | 18 | .285 |
| 17 | 89 | 51 | 0 | 104 | 72 | 96 | 75 | 0 | 5 | 20 | .282 |
| 18 | 89 | 55 | 0 | 104 | 72 | 95 | 74 | 0 | 7 | 22 | .233 |
| 19 | 91 | 57 | 0 | 103 | 74 | 96 | 75 | 0 | 9 | 24 | .478 |
| 20 | 92 | 53 | 0 | 104 | 71 | 96 | 76 | 0 | 8 | 23 | .332 |
| 21 | 91 | 56 | 0 | 104 | 73 | 95 | 77 | 0 | 9 | 24 | .340 |
| 22 | 85 | 62 | 1.02 | 96 | 73 | 89 | 75 | 0 | 9 | 24 | .344 |
| 23 | 71 | 54 | .08 | 78 | 66 | 77 | 69 | 2 | 0 | 13 | .033 |
| 24 | 70 | 60 | .24 | 78 | 66 | 72 | 68 | 0 | 0 | 15 | .042 |
| 25 | 72 | 58 | .23 | 74 | 64 | 71 | 66 | 0 | 0 | 15 | .148 |
| 26 | 72 | 57 | .09 | 77 | 64 | 72 | 64 | 0 | 0 | 15 | .117 |
| 27 | 72 | 51 | .01 | 73 | 61 | 70 | 63 | 3 | 0 | 12 | .102 |
| 28 | 78 | 55 | 0 | 79 | 61 | 74 | 63 | 0 | 2 | 17 | .263 |
| 29 | 81 | 55 | 0 | 84 | 62 | 78 | 64 | 0 | 3 | 18 | .280 |
| 30 | 84 | 56 | 0 | 87 | 63 | 81 | 64 | 0 | 5 | 20 | .204 |
| 31 | 89 | 55 | 0 | 93 | 64 | 85 | 66 | 0 | 7 | 22 | .193 |
| Average/Total | 84.4 | 53.9 | 1.79 | 95.7 | 69.1 | 88.5 | 71.9 | 11 | 146 | 600 | 8.282 |
| Departure | 3.3 | 2.6 | 0.92 |   |   |   |   |   |   |   |   |