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Early Season, Deliberate Pace

Willamette Valley — April 20, 2026

Where We Stand

Bud break recorded April 4. Sixteen days later, the valley sits at 124 cumulative GDD (base 50F), with 20 of those added over the past week. The week that just closed brought a high of 72F against a low of 33F — a wide diurnal swing — and 1.06 inches of precipitation. The vines are moving, but the calendar and the thermometer are not in a hurry.

The Week Ahead

Tuesday is the hinge. Models show the week opening dry today at 72F before a shift brings 0.5 inch Wednesday, a trace Thursday, then clearing through the weekend with highs running 63F, 68F, and 69F before settling back to 62F on Sunday. Total forecast precipitation comes to 0.55 inches across seven days, with the overwhelming majority falling in a single 24-hour window. The back half of the week recovers well, and the pattern indicates accumulating degree days into the weekend — the kind of stretch that keeps pre-bloom development on a measured trajectory rather than stalling it.

Season Context

The valley is 20 days into the season by the April 1 baseline. At 124 GDD through the 20th, the season is tracking at a pace that reflects the cool nights and the modest daytime warmth that has characterized April so far. The phenological position shoot growth — pre-bloom, following a bud break in the first week of April — is consistent with where that accumulation puts the crop developmentally. The gap between the 72F weekly high and the 33F low signaled that radiation frost exposure remained a live consideration for low-lying sites. .

What warrants attention over the next two weeks is how quickly GDD accumulates once the mid-week system clears. If the pattern holds and the back half of April runs warmer and drier than the first, the pace into bloom will accelerate — and the timing of that transition will matter more than any single day's temperature.

Season GDD Tracker

03571106142 Apr 01Apr 04Apr 07Apr 10Apr 13Apr 16Apr 19 124 GDD 2026 Cumulative GDD (Base 50F)
Cumulative Growing Degree Days (base 50F, cap 86F) from April 1. Willamette Valley, Oregon.

7-Day Outlook

Mon
Apr 20
72°
51°
Tue
Apr 21
🌧
56°
49°
0.52"
Wed
Apr 22
🌦
55°
44°
0.03"
Thu
Apr 23
63°
43°
Fri
Apr 24
68°
41°
Sat
Apr 25
69°
44°
Sun
Apr 26
🌦
62°
46°
0.04"
Last week at a glance: High 72F · Low 33F · 1.06" precip · 20 GDD accumulated · Season total: 124 GDD
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