Real weather for 50 San Francisco neighborhoods. Free API. No key required.

🌐 Live API: microclimates.solofounders.com

Use with Claude Code, Clawdbot, or build into your apps.

Built by Solo Founders.

SF has the most dramatic microclimates of any US city.

Weather apps say "San Francisco: 58°F" — but that's useless. It can be 52°F and foggy in the Outer Sunset while it's 65°F and sunny in the Mission, just 3 miles apart.

This API aggregates 150+ outdoor sensors and groups them by neighborhood, so you get actual local temperatures — not some airport reading from SFO.

curl https://microclimates.solofounders.com/sf-weather/mission

{
  "neighborhood": "mission",
  "name": "Mission District",
  "temp_f": 58,
  "humidity": 52,
  "sensor_count": 8
}

No API key. No signup. Just use it.

Copy and paste this into your skills folder:

# Create a new skill: sf-microclimates/SKILL.md


# SF Microclimates Skill

Get real-time SF neighborhood weather.

## Triggers
- "weather in [neighborhood]"
- "sf weather mission vs sunset"
- "is it foggy in the richmond?"

## Usage
curl https://microclimates.solofounders.com/sf-weather/marina

## Neighborhoods
mission, castro, marina, soma, haight, noe_valley,
outer_sunset, inner_sunset, outer_richmond, presidio,
north_beach, pacific_heights, potrero, twin_peaks...

• AI agents — Give your agent real local weather context
• Home automation — Trigger based on your actual neighborhood temp
• Slack/Discord bots — Settle "is it foggy?" arguments
• Travel apps — Show tourists what to actually expect
• Personal dashboards — Finally, weather that matches your window

From Marina to Noe Valley, Presidio to Twin Peaks — every SF neighborhood mapped.

curl https://microclimates.solofounders.com/neighborhoods

Includes: mission, castro, marina, soma, haight, noe_valley, outer_sunset, inner_richmond, north_beach, pacific_heights, potrero, dogpatch, bayview, twin_peaks, presidio, tenderloin, chinatown, japantown, cole_valley, glen_park, and 30 more.

{
  "updated": "2026-01-25T23:00:00.000Z",
  "neighborhood": "outer_sunset",
  "name": "Outer Sunset",
  "temp_f": 52,
  "humidity": 78,
  "sensor_count": 15
}

{
  "updated": "2026-01-25T23:00:00.000Z",
  "neighborhoods": {
    "mission": { "temp_f": 58, "humidity": 52, "sensor_count": 8 },
    "outer_sunset": { "temp_f": 52, "humidity": 78, "sensor_count": 15 },
    "marina": { "temp_f": 55, "humidity": 65, "sensor_count": 6 }
  }
}

Want to run your own instance?

git clone https://github.com/solo-founders/sf-microclimates.git
cd sf-microclimates
npm install

This API uses PurpleAir sensors. Sign up at develop.purpleair.com — free for personal use.

wrangler kv:namespace create "CACHE"

Add the output to wrangler.toml:

[[kv_namespaces]]
binding = "CACHE"
id = "your-kv-namespace-id"

wrangler secret put PURPLEAIR_API_KEY

echo "PURPLEAIR_API_KEY=your-key" > .dev.vars
wrangler dev

1. Request comes in → rate limit check
2. Check Cloudflare KV cache → return if fresh
3. Cache miss → fetch outdoor sensors from PurpleAir (location_type=0)
4. Group sensors by neighborhood GPS bounding boxes
5. Calculate averages, cache for 1 hour
6. Return JSON with CORS headers

LA, Seattle, NYC, Chicago, Austin — every city has microclimates.

The neighborhood bounding boxes are in src/index.ts. To adapt:

1. Update SF_NEIGHBORHOODS with your city's areas + GPS coordinates
2. Change the PurpleAir bounding box to your city
3. Update branding
4. Deploy

PRs welcome! We'd love to see la-microclimates, nyc-microclimates, etc.

MIT — use it however you want.