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Pre-Bloom in the Sun, a little moisture: Willamette Valley

Willamette Valley — May 11, 2026

Where We Stand

Through May 11, the valley has accumulated 226 cumulative growing degree days (base 50F), with 71 of those arriving in the past seven days alone. That's a meaningful single-week contribution — warm days reaching 76F, nights holding at 45F, and no precipitation. Bud break landed on April 4, putting us 41 days into the season and firmly in pre-bloom. The vines are moving.

The Week Ahead

The next two days carry the warmth forward, with models showing highs of 76F and 78F and no precipitation. Then the pattern shifts. Wednesday brings a drop to 58F with 0.19 inches of rain — modest, but enough to note. Thursday recovers to 66F before another softer stretch: 56F, 59F, and 62F through the weekend, with trace precipitation on Friday (0.12") and Saturday (0.02"). The back half of the week is cooler and intermittently wet, though not dramatically so. GDD accumulation will slow through that stretch, but it won't stop.

Season Context

A 226 GDD position at this point in May, coming off a week of sustained warmth and zero rainfall, reflects a season that has banked heat efficiently since early April. The pre-bloom designation matters here: the valley is at a stage where temperature consistency over the next several weeks will carry more weight than any single day's high. The mid-week cooling interrupts what has been a clean heat accumulation run, but the larger question is how the pattern holds through late May — that window will do a great deal to shape bloom timing and set. The shift in this week's forecast is the first real disruption of the season's early momentum, and what follows it is worth watching closely.

Season GDD Tracker

064129194259 Apr 01Apr 07Apr 13Apr 19Apr 25May 01May 07 226 GDD 2026 Cumulative GDD (Base 50F)
Cumulative Growing Degree Days (base 50F, cap 86F) from April 1. Willamette Valley, Oregon.

7-Day Outlook

Mon
May 11
76°
47°
Tue
May 12
78°
53°
Wed
May 13
🌧
58°
48°
0.19"
Thu
May 14
66°
45°
Fri
May 15
🌧
56°
42°
0.12"
Sat
May 16
🌦
59°
38°
0.02"
Sun
May 17
62°
38°
This week at a glance: High 76F · Low 45F · 0.00" precip · 71 GDD accumulated · Season total: 226 GDD
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