Beyond everyday mobility, road accessibility was critical. The transport networks enabled the delivery of essential goods — including food and COVID-19 vaccines — at a time when logistics could not afford disruption.
For the evaluation we focused on the following questions:
Where did the greatest impact actually occur?
Which municipalities were most affected?
Who responded the fastest?
How long did full recovery take?
We processed satellite imagery from before, during, and after the storm to map snow extent and track its evolution between 6 January and 5 February 2021.
We integrated official road infrastructure data from open sources to analyse exposure and disruption at municipal level.
We measured snow impact through change detection against a pre-storm baseline. Snow-covered roads exhibit a different spectral response than exposed pavement, allowing us to identify:
– Which roads were affected
By analysing multiple dates, we also captured the progression of snow removal efforts across the region.
We generated operational indicators, including:
Quick response rate — the reduction in snow-covered road surface between the first two recorded dates.
Cleaning time — the number of days required to clear 90% of affected roads.
These indicators provided an objective measure of response efficiency across municipalities.
More than 400 roads around Madrid experienced significant disruption during Filomena.
In some areas, full clearance required more than 9 days.