Fall mood changes typically begin in late fall or early winter, but the window to get ahead of them is now — the four to six weeks before symptoms take hold. Protecting your sleep schedule, front-loading morning light, keeping movement and social contact on the calendar, and starting treatment early are all more effective as prevention than as rescue. Seasonal affective disorder symptoms last about four to five months a year and respond well to treatment.
Today is the equinox. From here until late December, the Pacific Northwest loses daylight at the fastest rate of the year — a few minutes every morning, a few more every evening, compounding quietly until one week in November it registers as when did it get dark at 4:30.
For a lot of people in Oregon and Southwest Washington, that’s also the point at which their mood has already been sliding for six weeks.
Here’s the thing that makes fall different from every other mental health topic: you know it’s coming. You have the appointment on the calendar. Which means, unusually, prevention is actually on the table.
Why fall hits harder here
Seasonal affective disorder is depression with a recurring seasonal pattern, and according to the National Institute of Mental Health, symptoms last about four to five months out of the year. In most cases they start in late fall or early winter and lift in spring or summer — what clinicians call winter-pattern SAD.
Geography matters. NIMH notes that SAD is more common in people living farther north, where winter daylight hours are shorter: “people in Alaska or New England are more likely to develop SAD than people in Texas or Florida.”
Portland sits at roughly 45.5° north. Salem, Eugene, Bend, and Vancouver are all in the same band. That’s north of Minneapolis. Add the marine layer — the specific Willamette Valley phenomenon where it isn’t raining, exactly, but the sky is a uniform lid from October to April — and you get long stretches with very little bright light reaching your eyes even in the middle of the day.
This isn’t regional folklore. It’s latitude plus cloud cover, and it’s why “the gray” is a normal topic of conversation here in a way it isn’t in Denver.
If you want the full clinical picture, our explainer on seasonal affective disorder symptoms and causes covers the diagnostic side. This post is about the six weeks in front of you.
What early fall mood changes actually look like
They rarely announce themselves as sadness. The early signs are usually physical and behavioral:
– Sleeping more and feeling less rested. Winter-pattern SAD often involves oversleeping rather than insomnia.
– Carbohydrate cravings and appetite increase. Also characteristic of winter-pattern seasonal depression, and often mistaken for a willpower problem.
– Afternoon energy collapse that’s noticeably worse than your summer baseline. – Social attrition. Not deciding to withdraw — just finding that plans get declined and it’s been three weeks since you saw anyone.
– Morning dread that wasn’t there in July.
– Task drift. Things that were easy in August take three days in October.
Notice how many of those are easy to attribute to something else: a busy quarter, bad sleep, getting older, the news. That misattribution is the main reason people don’t act until December.
The six-week prevention window
Everything below is more effective started now than started in November. That’s the entire argument of this post.
- Anchor your wake time before the clocks change
Daylight saving time ends Sunday, November 1, 2026. The single highest-leverage move available to you is a wake time that doesn’t drift — same time, weekends included, within about an hour.
Your circadian rhythm is set primarily by light exposure at consistent times, and a stable wake time keeps that signal legible. When wake time slides later through October and then the clocks jump, the misalignment does real damage to mood and energy. NIMH lists consistent sleep schedules and reducing blue light before bed among its core recommendations for caring for your mental health.
- Get light into your eyes in the first hour of the day
Morning light is the strongest available signal to your circadian system, and outdoor light on an overcast Pacific Northwest morning is still dramatically brighter than indoor lighting.
Twenty minutes outside before 9 a.m. — walk the dog, drink your coffee on the porch, park farther away. It doesn’t have to be sunny. It has to be outside.
On light therapy: for SAD specifically, NIMH describes light therapy using a 10,000-lux light box for 30 to 45 minutes daily, typically first thing in the morning through fall and winter. Light boxes are inexpensive and available without a prescription, but they aren’t right for everyone — notably, they can trigger mood episodes in people with bipolar disorder. Talk to a provider before starting one, particularly if you have bipolar disorder or an eye condition.
- Put movement on the calendar before you stop wanting it
Motivation is the thing seasonal depression takes first. Anything that depends on wanting to do it will fail in November.
So schedule it now, while wanting to is still available: a standing walk with a friend, a class you’ve paid for, a gym visit attached to your commute. NIMH’s guidance is modest and achievable: “Just 30 minutes of walking every day can boost your mood and improve your health.” The specific activity matters much less than whether it’s on a calendar rather than in your intentions.
- Schedule the social contact too
Isolation both signals and worsens depression, and in fall it happens by default rather than by decision — dark evenings simply make staying in the easier option every single time.
Standing plans survive the season. Spontaneous ones don’t. One recurring commitment a week, already on the calendar, will outperform a general intention to see people more.
- Move every day: join and go to a gym frequently, or work out at home. Get rain gear and walk outside. It is a challenge in the darker months, but an easy fix. All you need is 30 minutes most days of the week (150 minutes per week is the sweet spot).
- If you’ve had this before, treat it before it starts
This is the part most people get wrong.
If you’ve had seasonal depression in previous years, you don’t have to wait for the symptoms to arrive to talk to a provider. Preventive strategies exist — adjusting an existing antidepressant ahead of the season, starting light therapy in early fall rather than mid-winter, beginning therapy while your capacity is still intact.
NIMH lists four evidence-based approaches for SAD: light therapy, cognitive behavioral therapy adapted for SAD (CBT-SAD), antidepressant medication — SSRIs and bupropion specifically — and vitamin D, though it notes the research on vitamin D shows mixed results. A medication management appointment in September is a fundamentally different conversation than the same appointment in January, when you’re already six weeks into it and running on nothing.
When it’s more than a seasonal dip
Get help now rather than waiting for spring if:
– Symptoms have lasted two weeks or longer and are severe or distressing — NIMH’s own threshold for seeking professional help
– You can’t keep up with work, school, or self-care
– You’re sleeping far more than usual and still exhausted
– You’ve withdrawn from nearly everyone
– You’ve had thoughts of self-harm — this is an immediate reason to reach out, and the 988 Suicide & Crisis Lifeline is available 24/7 by call, text, or chat
One more, specific to this topic: if seasonal depression has gotten worse every year for several years, that’s a pattern worth treating properly rather than enduring again. Recurrent seasonal episodes can compound, and “I get through it eventually” is a low bar for four to five months of every year.
If antidepressants haven’t held through past winters, treatment-resistant depression has its own pathway — including TMS therapy — and starting an evaluation in the fall means treatment can be underway before the worst of it.
The actual point
You have information most people never get about a mental health condition: a rough start date.
Six weeks from now, some version of this is likely arriving. Use the window. Anchor the wake time, get the morning light, put the walk and the friend on the calendar, and if you’ve been through this before, make the appointment while you still have the energy to make it.
Contact us or call (971) 300-0654 to talk through options across Oregon and Washington — including telehealth, which is a genuinely easier thing to commit to in January than a drive.
If you are in crisis, call or text 988 to reach the 988 Suicide & Crisis Lifeline, available 24/7.
Frequently Asked Questions
When does seasonal depression usually start?
In most cases, winter-pattern SAD symptoms begin in late fall or early winter and lift in spring or summer, lasting about four to five months out of the year. Early signs often appear before that — oversleeping, carbohydrate cravings, afternoon energy crashes, and social withdrawal can begin as daylight starts dropping in September and October.
Is seasonal depression worse in the Pacific Northwest?
Risk rises with latitude, and NIMH notes SAD is more common in people living farther north where winter daylight hours are shorter. Portland, Salem, Eugene, Bend, and Vancouver all sit around 44–46° north, and persistent overcast conditions further reduce bright light exposure. Individual risk still varies widely.
Can you prevent seasonal affective disorder?
You can’t guarantee prevention, but early action helps. Anchoring a consistent wake time, getting outdoor light in the first hour of the day, scheduling movement and social contact before motivation drops, and — for people with a history of seasonal episodes — starting treatment preventively in early fall are all more effective started before symptoms take hold than after.
Do light therapy boxes work for fall and winter depression?
Light therapy is one of NIMH’s listed treatments for SAD, typically using a 10,000-lux light box for 30 to 45 minutes daily, usually first thing in the morning through fall and winter. Light boxes aren’t appropriate for everyone — they can trigger mood episodes in people with bipolar disorder — so talk to a provider before starting one.
What’s the difference between fall mood changes and seasonal affective disorder?
Mild seasonal dips in energy and mood are common and don’t necessarily meet criteria for a disorder. SAD is diagnosed when depressive symptoms follow a recurring seasonal pattern and are significant enough to affect functioning. The practical threshold for seeking help is the same either way: symptoms lasting two weeks or longer that are severe or distressing, or that interfere with work, school, relationships, or self-care.
Should I wait until winter to see a provider about seasonal depression?
No. An appointment in September is a different and more productive conversation than the same appointment in January, when symptoms are already established and energy is lowest. If you’ve had seasonal depression in past years, preventive options — adjusting an existing medication ahead of the season, starting light therapy early, or beginning therapy while capacity is intact — are available now.
