You can now view i4cast, ECMWF, GFS, and ICON forecasts side by side, flag your event of interest, and get a recommendation based on how much they agree.
The problem is the process: multiple open tabs, different scales, misaligned readings, and no clear local reference.
From now on, that comparison happens inside i4cast, with our high-resolution forecast as the reference. The feature is available for locations in Brazil.
On the Forecast screen, the meteogram now has a selector. By tapping "Model", you switch between the forecasts available for that point, keeping the variables and time range you were already analyzing.
The available forecasts are:
| Forecast | Produced by | Resolution |
|---|---|---|
| i4cast 👑 | i4sea, combining global data, local refinement, and AI | 3 km |
| ECMWF | European Centre for Medium-Range Weather Forecasts (ECMWF) | 9 km |
| ICON | DWD, the German national weather service | 13 km |
| GFS | NOAA (USA), free global forecast | 25 km |
The resolution, shown next to each forecast's name, indicates the size of the grid cell used in the computation. The smaller the number, the greater the level of local detail.
That's why i4cast, at 3 km, can capture phenomena that global forecasts may miss. It's also why it appears as the reference in the comparison.
If in doubt, the "What are forecast models?" link opens a summary of each forecast right on the screen.
The platform also shows the last update of the selected forecast, the estimated time of the next update, and a warning when any forecast has delayed data.
The "View combined forecasts" button opens a new visualization: a table with one block per forecast. All blocks are aligned on the same hourly timeline, with a "(Now)" marker and a synchronized cursor. The same column always represents the same hour, in any forecast.
In the table, you control:
Variables: wind and gusts (at 10, 50, and 100 m), temperature, dew point, humidity, rain, and visibility, organized by theme in the sidebar.
Time range: 24h, 48h, 72h, or the maximum available horizon.
Quick reading: wind and gust cells colored by intensity, with a direction arrow. The legend separates "Value intensity" from "Threshold reached".
When a forecast doesn't cover a variable, the table states it clearly: "This forecast model does not provide this data". That way, an empty cell doesn't turn into a question mark.
Comparing numbers helps. Comparing your risk helps you decide.
When you enter the screen, you choose how to use the comparison:
From an event (recommended): select one of your saved events. i4cast uses the thresholds already configured in it, including "AND"/"OR" combinations, such as wind above 20 knots and visibility below 1 mile.
Raw data, no event: use the pure comparison table. You can activate an event later, right from the table, or set thresholds manually, with one value per variable, without having to create an event.
With an active event, three visual layers appear at the same time:
The "Selected event" row above the tables, with bands over the periods when the event is forecast.
A vertical highlight running across all forecasts within the event window, to quickly show what each one indicates.
Colored cells at the points where each condition of the event is met, forecast by forecast.
This was the most frequent question during user testing: "and when the forecasts disagree, what do I do?"
When you hover over the event, the platform shows how many forecasts captured it in that period, such as "3 out of 4", and turns that reading into a recommendation with a confidence badge. The badge ranges from "Very high confidence", when all forecasts agree and the event is near, to "Under watch", when the event is still far away and appears in a single source.
Each recommendation ends with a clear action, such as "Count on the event happening", "Treat the event as likely and have a backup plan", or "Keep it on your radar and monitor it".
How to use agreement and lead time when making decisions is the subject of our next post.
The comparison is available for locations in Brazil, for the meteorological variables: wind, gusts, temperature, humidity, rain, and visibility.
Waves, water level, currents, and water temperature remain exclusive to i4cast. Today, there are no comparable alternative forecasts for these variables.
Your choices are saved. The forecast selected per location, the table layout, the thresholds, and the active event are remembered between visits.
Fewer open tabs, more context to decide. The global forecasts you already consulted are now inside i4cast, aligned on the same timeline, compared against your event of interest, and translated into an objective recommendation.