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Created by
Linus Magnusson, last updated on Jun 18, 2026
6 minute read
Material from: Linus, David, ..
1. Overview
On 20 January the storm Harry impacted the southern-central Mediterranean with extreme rainfall and waves.
Storm Harry impacted several Mediterranean countries between 16 and 23 January 2026, causing widespread destruction and loss of life. The storm produced gusts up to 81 mph (130 km/h) and a central pressure of 995 hPa, contributing to severe coastal flooding, landslides, and infrastructure failures across the Mediterranean basin. The hardest‑hit regions included southern Italy, where waves exceeding 8 metres, gale‑force winds, and up to 300 mm of rain in 48 hours forced evacuations, collapsed seafronts, washed out roads, and halted ferry services.
https://www.linkedin.com/pulse/cyclone-harry-southern-italy-between-extreme-disyf/
Here is a link to an ECMWF Newsletter about the event:
https://www.ecmwf.int/en/newsletter/187/news/forecasting-storm-harry-mediterranean
2. Analyses and Observations
2.1 Event Definition
Link to Weather Replay: https://weather-replay.climate.copernicus.eu/?dt=491328&z=4.3&a=38.8&o=6.7&l=000110000110000
Here we will focus on 24-hour maximum significant wave height on 20 January in a 0.5x0.5 degree box south-east of Sicily (centred on 36.2N, 15.3E).
We will also evaluate the 3-day precipitation on 19-21 January in one 0.5x0.5 box on Sicily (37.7N, 15E) and one box over north-eastern Tunisia (36.5N, 10.5E).
2.2 Analyses
The plots below show analyses of MSLP and 6 hour rainfall from 18 January 00UTC to 22 January 00UTC, every 12th hour
The plots below show analyses of z500 and T850 from 14 January to 23 January, every 24 hour.
2.3 Observations
2.4 Climatological perspective
3. Forecasts
3.1 Data assimilation and observation usage
3.2 Single Forecasts for the event based on 00UTC forecasts (defined in Section 2.1)
The plots below show the forecasts for the wave event.
Analysis for the event
Control forecast (IFS 9-km resolution)
DestinE (IFS 4.4km resolution)
AIFS-single (AIFSv2.0 ~0.25 resolution)
AIFS-CRPS ensemble (~0.25 degree resolution)
3.3 Ensemble distribution
EFI (based on IFS 9-km ensemble)
The plots below show the EFI for 24-hour maximum significant wave height valid 20 January.
The plots below show the EFI for 3-day precipitation valid 19-21 January.
Forecast Evolution plot
The evolution plot below shows the forecasts for maximum significant wave height on 20 January inside the box south-east of Sicily. For AIFS version 2 (orange) is used as that version is the first with wave forecasts.
The evolution plot below shows the forecasts for precipitation on 19-21 January inside the boxes on Sicily and in Tunisia outlined in the observation plots below.
3.4 Sub-seasonal forecasts
3.5 Comparison with other centres
4. Hazard Forecasts
5. Dedicated Experiments
6. Event Summary
6.1 Good and bad aspects of the forecasts for the event
- Early signal in the forecast for the wave extreme
- Good signal for the precipitation over Sicily
- Less skill for the part of Tunisia