How to Convert Your Google My Maps into a Professional Forecast Map

Most weather forecasters who've been at this for a while have a Google My Maps graveyard.

You know the one. A collection of custom maps from past storm setups — county-level threat zones for that March nor'easter, a snowfall gradient from last January's coastal event, overlapping coverage polygons you spent an hour getting right. Useful at the time. Now sitting there, basically undiscoverable, tied to your Google account.

Here's how to put those to work.

Why forecasters use Google My Maps

Google My Maps is legitimately good for sketching coverage areas. It's free, it runs in any browser, and sharing a link is one step. A lot of indie forecasters use it as their working scratchpad when setting up a new outlook — draw the threat zones, label them, share the link in a tweet or a YouTube community post.

The problem: a shared Google Maps link is a dead end. Viewers can see the regions, but they can't get a forecast with it. They can't subscribe to updates. There's no verification record after the event. The map is the product, and it's not a great product.

ForecasterHQ is designed to be the next step.

What the import tool does

ForecasterHQ's import tool lives at forecasterhq.com/import. It accepts two inputs:

A Google My Maps link — the standard google.com/maps/d/viewer?mid=... URL. The tool fetches the KML behind the URL and parses the polygon layers into usable forecast regions.
A file upload — .kml, .geojson, or .json files up to 5MB. Works with exports from Google My Maps, ArcGIS, QGIS, or any GIS tool that outputs standard formats.

Either way, the result is the same: your polygons appear on an interactive map preview, labeled and ready to use. From there, one click carries them into the forecast creation wizard.

Step-by-step: importing a Google My Maps link

1. Get your Google My Maps share link.

Open your map in Google My Maps. Click the share icon → "Copy link." The URL will look like: https://www.google.com/maps/d/viewer?mid=1abc...xyz

That's the link you want.

2. Paste it into forecasterhq.com/import.

The tool fetches the KML data from Google's servers — this takes 2-4 seconds depending on how many layers your map has.

3. Check the preview.

Your regions appear on an interactive map. Zoom in, confirm the boundaries look right. If Google My Maps assigned colors to your polygons, ForecasterHQ picks those up too.

The tool will tell you if any non-polygon features (points, lines) were skipped — those don't translate to forecast regions.

4. Hit "Create Forecast with These Regions."

Your regions carry into the forecast wizard pre-loaded. You fill in the accumulation ranges, timing phases, and narrative — all the actual forecast content. The geographic legwork is already done.

Step-by-step: uploading a KML or GeoJSON file

If you export from a desktop GIS tool, the file upload path is cleaner than the URL method. Drag your file onto the upload zone (or click to browse), and ForecasterHQ parses it client-side — nothing is sent to a server until you choose to create a forecast.

Supported exports:

Google My Maps: File → Export to KML/KMZ (choose KML, not KMZ)
QGIS: Layer → Export → Save Features As → GeoJSON
ArcGIS Online: Export → GeoJSON

What you end up with

Once you publish the forecast, it lives at your ForecasterHQ profile URL — a shareable page with the interactive map, your accumulation ranges by region, the event timeline, and (after the event) a verification record pulled from NWS observations.

That last part is the piece Google My Maps can't do. A forecast is a prediction with a timestamp. When the event passes, ForecasterHQ pulls observed data and shows how your call compared to what actually happened. That's your verification record — public, searchable, and attached to your forecaster identity.

Your Google My Maps was a sketch. This is the published version.

Ready to import your map? Try it at forecasterhq.com/import — no account required to preview your regions. Account required to publish.