Weather Forecast Map Maker: Draw and Publish Regional Forecasts Online

You've seen those forecast maps in your feed — color-coded zones showing where the heavy snow band sets up, which counties are in the highest wind threat, where the rain-snow line is expected to fall. They look polished. They look authoritative. And the forecasters posting them have built real audiences around them.

Here's how to make your own.

ForecasterHQ includes a built-in weather forecast map maker designed specifically for independent forecasters. No GIS degree required. No Photoshop. No stitching together a satellite image in Google Slides and calling it a forecast map. You draw the regions directly on an interactive map, label them, assign accumulation ranges, and publish — all in one workflow.

This post walks through it step by step.

Why custom forecast maps matter

Most weather apps show you the same NWS forecast your neighbors are reading. What independent forecasters offer is something different: a specific, named call for a specific place, made by a specific person with a track record you can check.

The map is what makes that concrete. When you draw a distinct heavy accumulation zone versus a lighter zone versus a rain zone, you're doing the thing that separates a real forecast from a weather-app screenshot. You're on record. You're saying this place, this outcome.

That specificity is what builds an audience. It's also what gets verified after the event — ForecasterHQ ties your published forecast to real NWS observation data so viewers can see exactly how close your call was. (More on verification here.)

The map drawing workflow

Step 1: Start a new forecast

Go to your ForecasterHQ dashboard and click "New Forecast." The creation wizard walks you through the basics — event name, forecast type, timing — before opening the map editor.

If you already have regions drawn in Google My Maps or a GIS tool, you can import a KML or GeoJSON file instead of drawing from scratch. For most forecasters, drawing directly in the tool is faster.

Step 2: Draw your forecast regions

The map editor uses Terra Draw — an open-source drawing library built for precision geographic work. The toolbar on the left gives you four main tools:

Polygon — Draw a custom region by clicking to place vertices. Click back on your starting point to close the shape. This is the tool you'll use most.
Rectangle — Faster for rough bounding boxes, but most forecast regions aren't rectangular. Good for zooming in on an area before switching to polygon mode.
Circle — Useful for point-source threat areas like severe thunderstorm watch circles.
Select — Click any drawn region to move it, reshape it, or delete it.

Drawing a polygon: Click once to place your first point. Keep clicking around the perimeter of your zone. For county-level precision, zoom in to your county boundaries before drawing — the base map shows county lines at mid-zoom levels. When you're satisfied with the shape, click your starting point to close it.

Editing a shape after drawing: Click the Select tool, then click your region. Vertices appear — drag them to adjust. To add a vertex mid-edge, click on any edge segment.

You can draw as many regions as your forecast needs. A typical snowfall forecast might have four to six zones: extreme accumulation, high, moderate, light, and a rain zone. A severe weather outlook might have a tornado threat zone, a damaging wind zone, and a large hail zone.

Step 3: Label your regions

Once a region is drawn, click it to open the region editor on the right side. Each region gets:

A name — What this zone represents. "Heavy accumulation," "Elevated threat," "Primary snow band," etc. Keep it clear; this is what viewers read.
A color — ForecasterHQ suggests a default color scheme based on forecast type, but you can customize. Snow forecasts typically use blue gradients. Severe weather uses the standard red/orange/yellow threat scale.

Consistent labeling across your forecasts helps your audience learn to read your maps quickly. If you always use the same color for your highest accumulation zone, viewers develop a visual shorthand for your work.

Step 4: Set accumulation ranges by region

This is where a map becomes a forecast. After labeling, each region gets an accumulation or intensity range — the specific call for that zone.

For a snowfall forecast, you'd set ranges like:

Heavy zone: 12–18 inches
Moderate zone: 6–10 inches
Light zone: 2–4 inches
Rain zone: 0 inches / rain

For a wind forecast:

Primary zone: 50–65 mph gusts
Secondary zone: 35–45 mph gusts

The ranges display on the published forecast alongside the map — viewers can click any region and see exactly what you're calling for that area. This is the atomic unit of a verifiable forecast: a named region with a specific range, tied to a real event date.

Step 5: Add timing phases (optional but recommended)

Complex events have multiple timing phases. The map editor lets you set separate accumulation windows — morning vs. afternoon, pre-changeover vs. post-changeover. Each phase gets its own region assignments.

This is particularly useful for winter storms where the rain-to-snow changeover line is the critical call. You can show the rain zone through 6 AM, then show the same area flipping to light snow for the remainder of the event.

Step 6: Publish

Click "Publish." Your forecast gets a permanent URL at your ForecasterHQ profile — something like forecasterhq.com/storm/your-handle/january-2026-nor'easter.

That URL is what you share on X, YouTube, Substack, wherever your audience is. The page is readable on mobile without any special formatting from you. The map is interactive — viewers can click regions and zoom in. Your name and track record are attached.

After the event: verification

The map you drew isn't just a visual. After your event date passes, ForecasterHQ pulls NWS observation data from weather stations across your forecast area and compares it to your regional calls.

You end up with a verification record — how your heavy zone compared to what actually fell, how your timing held up. That record is public, attached to your forecast, and part of your overall forecaster track record.

Most forecasters don't get verified. You will. That's a competitive advantage that compounds over time. Your audience can see not just that you made a call, but how accurate those calls have been across dozens of events.

See how verification works on a live forecast.

Who this is for

You don't need a meteorology degree to use the map maker. Most of ForecasterHQ's heaviest users are:

Storm enthusiasts who've been doing their own analysis for years but sharing it informally on X or Discord
Broadcast meteorologists building an independent brand alongside their day job
Retired NWS forecasters who still want to make calls and have somewhere to put them
Weather students building a portfolio before entering the field

If you can read a model output and make a call, you can publish that call on a professional map.

Pricing

The map maker and forecast publishing features are included in ForecasterHQ's free tier. You can draw regions, publish forecasts, and get verification records without paying anything.

See what's included at each tier.

Ready to draw your first map? Create your free forecaster profile and open the forecast wizard. Your first published forecast takes about 15 minutes from blank canvas to live page.

Or see a live forecast example first to understand what you're building toward.