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Bloom is likely imminent: The Season Holds Its Line

Willamette Valley — May 27, 2026

Where We Stand

Through May 27, the Willamette Valley has accumulated 355 cumulative growing degree days (base 50F), with 74 of those coming in the past seven days alone. That week included a high of 80F, a low of 46F, and 0.28 inches of precipitation — a snapshot of the push-and-pull that defines this time of year in the valley. Bud break was recorded April 4, putting us at day 57 of the season. Vines are in either in early stages, or imminently approaching, bloom. The architecture of the growing season is now largely set.

The Week Ahead

The seven-day forecast shows highs ranging from 66F to 83F, with the warmest day arriving on day two of the outlook. Precipitation is minimal — 0.11 inches and 0.01 inches on two days, nothing on the remaining five. The pattern indicates a predominantly dry stretch with enough warmth to sustain meaningful degree-day accumulation through the transition to bloom. The cooler days mid-week, with highs in the mid-to-upper 60s, reflect a transient marine influence before temperatures return to the mid-70s by the weekend.

Season Context

At 355 GDD on May 27 with pre-bloom phenology confirmed, the season is tracking in a range consistent with years that tend to offer a measured pace through fruit set — not racing, not stalled. The early bud break on April 4 front-loaded some risk, and the season has absorbed it. What the models show for the coming week — warmth without significant rain — is favorable timing relative to where the vines are in their cycle. The question over the next two to three weeks is how that 83F day and the broader accumulation pattern interact with the pace of bloom, and whether the tail of the forecast holds or gives way to a pattern change. Watch the degree-day curve as bloom approaches.

Season GDD Tracker

0101203305407 Apr 01Apr 10Apr 19Apr 28May 07May 16May 25 355 GDD 2026 Cumulative GDD (Base 50F)
Cumulative Growing Degree Days (base 50F, cap 86F) from April 1. Willamette Valley, Oregon.

7-Day Outlook

Wed
May 27
🌤
74°
48°
Thu
May 28
🌧
83°
56°
0.11"
Fri
May 29
🌦
67°
44°
0.01"
Sat
May 30
66°
40°
Sun
May 31
68°
38°
Mon
Jun 01
76°
40°
Tue
Jun 02
75°
48°
This week at a glance: High 80F · Low 46F · 0.28" precip · 74 GDD accumulated · Season total: 355 GDD
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