Privacy policy

Effective November 13, 2026. Swathline is operated by Diamond State Hail Solutions.

What Swathline is

Swathline shows recent United States hail, wind, and tornado reports on a map, draws hail swaths, and can shade counties by Census median household income. It is a weather display. It is not a social network and it does not scrape social media, forums, or private accounts.

Data we do not collect

No account is required to view the map.
Viewing the map does not read contacts, SMS, or your photo library.
We do not sell personal information and we do not show third-party ads.
We do not pull posts from X, Facebook, Instagram, or any other social platform.

Weather data

Live hail, wind, and tornado locations come from public National Weather Service alerts, Storm Prediction Center local storm reports, and Iowa Environmental Mesonet local storm reports. A county income layer uses a bundled American Community Survey cache (table B19013, median household income). An optional Census API key can refresh that cache on the server. Map tiles are loaded from OpenFreeMap.

Those sources describe weather and public statistics. They are not a profile of the person viewing the map.

Reports you submit

Spotter and community webhooks, and CSV or GeoJSON import, store the hail observation you send: location, time, size, and optional place name or remark. Webhooks in production require a shared secret. Imported files are treated as community or spotter observations and cannot overwrite official NWS confidence.

Report hail in the app sends a photo plus the pin you confirm, a hail size, and an optional note. The app asks for the camera or photo library, and for location only if you choose “Use my location.” You can place the pin by tapping the map instead. The photo is stored on the server volume and shown on the public map as a community report. We do not read GPS from the photo. JPEG, PNG, and WebP location metadata is removed when the file is saved. A hashed network address is kept briefly to limit how many reports one network can send.

Do not include a person's name, phone number, address of a private residence beyond the hail location, or any other personal data in a remark or photo. If you did, email us and we will delete that stored report and its photo.

Retention

Official feed rows older than eight days are removed on sync. Reports you import, post to a webhook, or submit with a photo stay until you ask us to delete them or we remove the database. The database and photo files live on the server volume, not on the phone, except for a short-lived cache of the app shell in the browser.

Phone alerts

If you turn on alerts, the browser creates a push subscription. Swathline stores that subscription, the areas you watch, quiet hours, and an optional last GPS fix for Near me. There is no name on that record. Radar hail, spotter reports, and National Weather Service warnings are checked on the server. A notification includes the place, hail size, and time, and opens the map or the address card. The subscription is deleted when you turn alerts off or when the push service says the browser is gone. iPhone alerts require adding Swathline to the Home Screen.

Optional team sign-in

Viewing the map does not require an account. Field notes, damage photos, and a watch list are stored only after you sign in with a name and the team passcode, or with an email and password. The name on a passcode login is the account. An email account stores the email address and a hashed password. Those notes and photos are not shown on the public map and are not labeled as official weather reports. A shareable storm report includes your field photos only when you generate it while signed in. Anyone with that link can open that one report.

If subscriptions are turned on, card numbers are entered on Stripe Checkout, not on Swathline. We store the Stripe customer id and whether the subscription is active. Stripe is the payment processor. We do not keep the card number.

Field mode can use your device location to show where you are and the damage score at that point. Location is requested only in Field mode, or when you choose it for a community hail photo. We do not read GPS from a photo file.

The Android app

The Swathline Android package com.hailmap.app is a WebView of the HTTPS site. It does not add a separate analytics SDK. Cleartext HTTP is disabled. Play data-safety answers that match this policy are in the repository under docs/data-safety.md.

Children

Swathline is not directed at children under 13 and we do not knowingly collect their personal information.

Changes

If this policy changes, the updated text will be published at this page with a new effective date.