We’ve been having a very mild weather here in the Pacific Northwest. The table below represents degree-day numbers for the last 3 years using 41 degrees as the base low temperature. These numbers are used to calculate the number of heat units per day, and compare them to years past. This is very useful in determining how far along certain crops are. See chart below:
| Station Location | 2015 | 2014 | 2013 |
| Year-to-date | Year-to-date | Year-to-date | |
| Abbotsford, B.C. | 321 | 135 | 117 |
| Aurora , OR | 473 | 265 | 227 |
| Bellingham, WA | 356 | 232 | 170 |
| Mount Vernon, WA | 374 | 221 | 174 |
| Corvallis, OR | 417 | 254 | 238 |
| Grandview, WA | 225 | 171 | 125 |
| Kelso-Longview, WA | 437 | 203 | 200 |
| Prosser, WA | 235 | 179 | 191 |
| Salem, OR | 455 | 276 | 276 |
Every location is reporting at least 50 more heat units this year compared to last year. 50 units represents a 3-5 day difference, so for locations like Aurora, OR with a 208 unit differential, we are looking at the crops to be 12-20 days ahead of last year. Eastern Washington numbers aren’t nearly as drastic due to colder low temperatures, but they are still 3-5 days ahead of 2014.
Since today is only March 10th, the biggest issue with early season crops will be frost danger. This will definitely be something to keep a close eye on moving forward, and the closer we get to bloom, the more vulnerable the plants and trees will be to cold weather. The early bearing fruit crops will be the most susceptible (peaches, apricots, nectarines, plums, berries, cherries).
