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Set and Go, Heat Coming

Willamette Valley — June 09, 2026

Where We Stand

Bloom peaked, depending on site, sometime around the week of June 2, and the valley closed out the first week of June with 406 cumulative GDD — season day 67 since April 1. This past week added 52 GDD on a high of 71F and a low of 43F, with 0.79 inches of precipitation. That rain total is notable in the context of what the next seven days show: none of it is coming back soon.

The Week Ahead

The forecast opens cool — 62F highs Monday and Tuesday, with 0.11 inches of rain expected Tuesday — then pivots sharply. Wednesday climbs to 76F, Thursday to 79F, Friday to 84F. Saturday reaches 94F, Sunday holds at 93F. That is a 32-degree swing across six days. The models are showing a late-week heat event that is not a brief anomaly; two consecutive days at or above 93F in the second week of June means the season accumulates GDD at a significantly accelerated rate through the weekend. The post-bloom period is when berry development begins and cell division is active. The cold nights this week — lows in the low-to-mid 40s behind a 71F high — reflect the diurnal variability that has defined the early season. What replaces that pattern over the weekend is a different regime entirely.

Season Context

Bud break on April 4 and bloom on June 2 give this vintage a 59-day bud-break-to-bloom interval. At 406 GDD through June 9, the season is tracking in a range that leaves meaningful room for the forecast heat to either normalize or extend the pace depending on what follows. The late-week spike will draw that cumulative number upward quickly. What matters now is whether this heat event is a transition into a sustained warm pattern or a sharp peak before the marine influence reasserts. The pattern through the end of June will answer that question.

Season GDD Tracker

0116233350467 Apr 01Apr 12Apr 23May 04May 15May 26Jun 06 406 GDD 2026 Cumulative GDD (Base 50F)
Cumulative Growing Degree Days (base 50F, cap 86F) from April 1. Willamette Valley, Oregon.

7-Day Outlook

Tue
Jun 09
62°
53°
Wed
Jun 10
🌧
62°
50°
0.11"
Thu
Jun 11
76°
43°
Fri
Jun 12
79°
47°
Sat
Jun 13
84°
48°
Sun
Jun 14
94°
56°
Mon
Jun 15
93°
60°
This week at a glance: High 71F · Low 43F · 0.79" precip · 52 GDD accumulated · Season total: 406 GDD
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