I Tracked My Mood Every Day for 90 Days During Fall - Here's What I Learned About My Seasonal Depression

Week 1-2 (September 1-14): "I Don't Need to Track Anything - I Know When I'm Sad"

I'll be honest: I rolled my eyes when my therapist suggested daily mood tracking. I'd been dealing with seasonal depression for seven years. I knew I got depressed in winter. What would writing it down accomplish?

But she was persistent. "Humor me for 90 days," she said. "September through November. Track your mood, energy, sleep, and one daily activity. That's it."

Fine. I downloaded Lifelight (she'd mentioned it had quick check-ins, which mattered because I knew I wouldn't write lengthy journal entries daily). The first week, I logged my mood maybe 4 out of 7 days. I felt... fine? Maybe a 7/10 most days. Energy was good. I was still going to outdoor concerts, meeting friends for happy hour, hiking on weekends.

Looking back at that first week now, I see what I couldn't then: This was my baseline. This is what "normal" felt like. I needed to capture it before it vanished.

Week 3-4 (September 15-30): Subtle Shifts I Almost Missed

By week three, I'd gotten into a rhythm. Logging my mood took literally 15 seconds before bed. The app would ask "How was your day?" and I'd tap a number 1-10 and add one quick note about what I did.

September 18: "7/10 - Felt a bit tired after work. Skipped yoga, ordered takeout instead."
September 22: "6/10 - Woke up groggy even after 9 hours of sleep. Weird."
September 25: "7/10 - Cancelled dinner plans. Just wanted to stay in."
September 28: "6/10 - Craving carbs like crazy. Ate an entire pizza myself."

None of these felt significant in the moment. I was still functional. Still working. Still "fine." But when I looked at my mood graph at the end of September, there it was: a gentle downward slope from 7-8/10 to 6-7/10.

Pattern #1 I discovered: My seasonal depression doesn't start with feeling "sad." It starts with subtle energy dips and social withdrawal that feel like normal tiredness or introversion.

Week 5-6 (October 1-14): The Pattern Becomes Undeniable

October hit, and things got interesting. I'd been tracking long enough that Lifelight started showing me patterns:

• My mood dropped an average of 1.5 points after 3+ consecutive days without sunlight
• On days I exercised outdoors in the morning, my mood averaged 7.2/10
• On days I skipped morning movement, my mood averaged 5.8/10
• My energy levels were now consistently lower than my September baseline

October 7 was a turning point. I woke up on a rare sunny Saturday feeling... nothing. Not sad, exactly. Just flat. Everything felt like too much effort. My friend texted about brunch, and I stared at the message for 20 minutes trying to decide if I had the energy to respond.

I logged it: "4/10 - Don't want to do anything. Feel empty."

That's when I actually looked at my mood calendar view. The visual hit me hard: I'd dropped from averaging 7-8/10 in early September to 5-6/10 by mid-October. Six weeks. That's all it took for the shift to happen.

Pattern #2 I discovered: The decline was gradual enough that I didn't notice day-to-day, but stark when visualized over weeks. This is why tracking matters—your memory lies, but data doesn't.

Week 7-8 (October 15-31): Daylight Savings Hits Like a Truck

I thought I understood seasonal depression. I was wrong. I had no idea how much the time change would wreck me.

October 29: "6/10 - Managed morning walk, felt okay"
November 3 (week after time change): "3/10 - So dark when I leave work. Felt like crying in my car for no reason."

Leaving work in darkness destroyed me in a way I hadn't anticipated. The same commute that had been fine in daylight suddenly felt suffocating. By 7 PM, I was exhausted. By 8 PM, I was in bed doom-scrolling, too tired to sleep but too depleted to do anything productive.

My tracked patterns during this period:

• Sleep: Increased from 7.5 to 9+ hours, yet I felt more tired
• Social activity: Declined invitations 8 out of 10 times (vs. 2 out of 10 in September)
• Exercise: Dropped from 5x/week to 1x/week
• Mood variance: More dramatic swings - either 3/10 or 7/10, rarely in between

Pattern #3 I discovered: The week after daylight savings is the highest-risk period. My mood dropped 2 full points in 7 days. If I'd known this was coming, I could have prepared.

Week 9-10 (November 1-14): Intervention Implementation

This is where mood tracking potentially saved my winter. Armed with 8 weeks of data showing an undeniable pattern, I couldn't deny something was seriously wrong.

I made three changes:

1. Ordered a light therapy lamp (should have done this in September, lesson learned)
Started using it 30 minutes every morning while having coffee. Honestly? The first week, I felt stupid sitting in front of a bright light. Week two, I noticed I wasn't hitting snooze 5 times anymore.

2. Committed to morning walks no matter what
Even 15 minutes. Even in the cold. Even when I didn't want to. I tracked every walk, and the correlation was clear: walk days averaged 6.5/10, no-walk days averaged 4.5/10.

3. Scheduled social commitments I couldn't cancel
Paid for a November yoga class series upfront (financial commitment = accountability). Scheduled weekly video calls with my sister. Joined a book club that met every Tuesday.

The impact wasn't immediate, but by week 10, my mood graph showed stabilization. Not back to September levels—I was still averaging 6/10 instead of 7-8/10—but I'd stopped the free fall.

November 12: "6/10 - Actually enjoyed book club tonight. First time I've felt social in weeks."

Week 11-12 (November 15-December 1): Recovery Patterns Observed

The final two weeks of my tracking experiment were revelatory. I could see—literally see in my data visualizations—what was working:

Interventions ranked by mood impact (based on my tracked data):

1. Morning outdoor time (even 10 minutes): +1.8 mood points on average
2. Light therapy lamp: +1.2 points (but only after 2+ weeks of consistent use)
3. Social interaction: +0.9 points (even when I dreaded it beforehand)
4. Good sleep (7-8 hours, not 9+): +0.7 points
5. Limited social media after 8 PM: +0.5 points

But here's what surprised me most: It wasn't just about what I did—it was about tracking itself.

The simple act of checking in with myself daily made me more aware of my emotional state. When I felt terrible, seeing that I'd logged "3/10" made me realize I needed to reach out for help rather than just powering through. When I felt okay, seeing "7/10" reminded me this was possible, even in November.

Lifelight's AI companion feature also became unexpectedly valuable. On nights when I was too exhausted to call friends but too anxious to sleep, I could just... talk. The AI would ask about my day, reflect back patterns ("I noticed you mentioned feeling tired after work three days in a row - what's different about this week?"), and offer gentle suggestions without feeling preachy.

The Key Insights I Never Would Have Discovered Without Daily Tracking

1. My seasonal depression has a 6-week onset period (September 1 - October 15)
This is MY timeline. Yours might be different. But now I know: late August is when I need to start prevention strategies, not October when symptoms are already present.

2. Weather isn't the only trigger - lack of structured routine is huge
My worst days weren't just cloudy days. They were unstructured days where I worked from home, didn't go outside, didn't talk to anyone. Even with perfect weather, those days tanked my mood.

3. "Social battery depletion" is actually depression lying to me
Every single time I forced myself to show up to social commitments despite dreading them, I rated the day 6+/10. Every time I cancelled, I rated it 5 or below. The pattern was 100% consistent. My gut instinct ("stay home, you're too tired") was wrong every time.

4. Small morning wins compound throughout the day
Days where I accomplished three tiny morning tasks (shower, 10-minute walk, light therapy) averaged 6.8/10. Days where I snoozed my alarm and skipped my routine averaged 4.2/10. Morning mood predicted day mood with 89% accuracy.

5. The correlation between sleep quantity and mood isn't linear
My best mood days: 7-8 hours of sleep.
My worst mood days: 9+ hours of sleep (even though it felt like I "needed" it).
Oversleeping was a symptom masquerading as a solution.

6. I needed visual proof to take my depression seriously
For years, I'd told myself "it's not that bad" or "everyone struggles in winter." Seeing the numerical decline from 8/10 to 4/10 over six weeks—displayed in a graph—made it undeniable. This wasn't normal tiredness. This was clinical depression. I needed treatment, not willpower.

What I Wish I'd Done Differently

Started tracking in late August instead of September 1. I would have caught the very beginning of the decline and had even more lead time for intervention.

Ordered the light therapy lamp in September, not October. By the time I started using it, I was already in a hole. Prevention is easier than recovery.

Shared my data with my therapist earlier. When I finally showed her my mood graphs in November, she immediately adjusted my treatment plan. That data was valuable clinical information—I should have shared it weeks earlier.

Tracked more variables. I focused on mood and activities, but I wish I'd also tracked caffeine intake, screen time, and time outdoors in minutes (not just yes/no). More data = better pattern recognition.

The Real Power of Mood Tracking: Your Past Becomes a Resource for Your Present

Here's what I didn't expect: This data isn't just useful for this year. It's a blueprint for every fall moving forward.

Now I know:

• Week 3-4 of September: Watch for subtle energy dips and increased carb cravings
• October 1: Start light therapy, no excuses
• October 15: Double down on outdoor morning time (critical window)
• November 1-10: Schedule extra social support during time change transition
• Throughout: Morning outdoor walks are non-negotiable - they're medication

This isn't generic advice from an article. This is my pattern, derived from my data, customized to my life.

Next September, I won't be caught off guard. I'll start interventions at week 3, before the decline even begins. I'll track again to see if the pattern holds (and adjust if it doesn't). I'll treat seasonal depression like the medical condition it is, not a personality flaw or weakness.

Why I'll Keep Tracking (Even Though 90 Days is Over)

On December 1, I hit my 90-day goal. I could have stopped. But here's the thing: tracking had become so easy that there was no reason to quit.

Lifelight's daily check-in takes 15 seconds. The AI asks how I'm doing, I tap a number and maybe add one sentence. That's it. In exchange, I get:

• Early warning system for future episodes
• Objective evidence of what helps vs. what doesn't
• Visual proof of progress on hard days
• Concrete data to share with healthcare providers
• Patterns that reveal insights I'd never notice otherwise

The 15 seconds is worth it.

My Advice If You're Considering Tracking Your Seasonal Depression

1. Start NOW, not when you feel bad. You need baseline data from when you feel good to compare against the decline. If you wait until you're depressed, you've missed the most valuable data.

2. Use an app that makes it EASY. You won't write pages in a journal when you're depressed. You need something that takes under 30 seconds. I used Lifelight because the daily check-in was literally "How are you feeling? 1-10" with optional notes. On my worst days, I could manage that.

3. Look at your data weekly. Don't just collect it—review it. Every Sunday, I'd spend 5 minutes looking at my week. Patterns emerged much faster this way.

4. Track at least 3 variables. Mood alone isn't enough. I tracked mood, energy, and one daily activity (exercise, social, outdoor time). The correlations between variables were the most revealing insights.

5. Commit to 90 days minimum. You need enough data to see patterns. 30 days won't cut it for seasonal depression - you need to capture the entire fall transition.

6. Share your data with your therapist/doctor. They can spot patterns you miss and adjust treatment based on objective data instead of your memory of "how things have been."

The Bottom Line: Tracking Changed How I Experience Seasonal Depression

I still get seasonal depression. The tracking experiment didn't cure me.

But it transformed how I manage it.

Instead of being blindsided every October, I have a playbook. Instead of guessing whether treatment is working, I have data. Instead of fighting alone in the dark, I have an AI companion that checks in daily and remembers my patterns even when I can't.

Most importantly: I take my depression seriously now. The visual evidence—watching my mood plummet from 8/10 to 4/10 over six weeks—made it impossible to dismiss my symptoms as "just tiredness" or "winter blues everyone experiences."

This is clinical depression. It's real. And thanks to 90 days of tracking, I finally have the tools to manage it.

If you've struggled with seasonal depression for years without understanding your pattern, I can't recommend mood tracking enough. Start today - September is not too early. October is not too late. Whenever you start, you're giving yourself the gift of self-knowledge.

Your future self will thank you.