Severe Storms Threaten Parts of Europe This Weekend

The European Severe Storms Forecast Experiment (ESTOFEX) has issued Level 2 storm alerts for portions of France, northeastern Spain, and northwestern Italy due to a heightened risk of very large hail, severe wind gusts, and heavy rainfall. These storms are expected to develop Saturday and persist into early Sunday (UTC).

🇫🇷 France

Strong afternoon storms will erupt over central and northeastern France, driven by intense surface heating and rich moisture. CAPE (Convective Available Potential Energy) values up to 2500 J/kg and deep-layer shear around 15–20 m/s support supercells capable of producing hail over 5 cm (2 in), damaging winds, and flash flooding.

Overnight, a progressive MCS (Mesoscale Convective System) could sweep into northeast France and into central Germany with an ongoing threat of hail and gusts, although surface wind risks diminish after sunset.

🇪🇸 NE Spain

A combination of steep lapse rates, rich low-level moisture, and daytime heating will drive thunderstorms capable of very large hail, severe downbursts, and torrential rain. Storms will initially form along the mountains before spreading eastward. Expect activity to weaken after sunset due to boundary layer drying.

🇮🇹 NW Italy

The highest instability of the day is forecast here, with MUCAPE values reaching 4000–5000 J/kg. Storms will initiate along the Alpine foothills and orography. Though deep-layer shear is modest (<10 m/s), initial storms may rapidly intensify and drop hail exceeding 5 cm (2 in), along with torrential rain and local downbursts. Some areas like South Piedmont (Piemonte) are particularly vulnerable despite weak initiation signals.

Here’s a throwback to 2023, when Italy set the record for largest hail in Europe twice in the same day:

Questo blocco di ghiaccio è stato trovato nel giardino di una casa di #Brugnera, devastata dalla grandine di lunedì sera.
Purtroppo, a causa dei danni, anche questa sera la pioggia continua ad entrare dal sottotetto ai piani inferiori. #maltempo #grandine #friuli #fvg pic.twitter.com/2oZXA4cg8L

— Telefriuli (@Telefriuli1) July 25, 2023

Rest of Europe

Surrounding Level 2 zones, Level 1 areas have been designated across:

• Germany and the Benelux: Storms may initiate along a prefrontal convergence zone, particularly in the afternoon, with risks for hail (up to 3–5 cm / 1.2–2 in) and severe wind gusts, especially if an MCS forms over northwest Germany.
• SW to central France: Overnight storms could produce swaths of hail and severe winds as they follow a stalling cold front eastward.
• Southern Turkey: Isolated severe storms may bring large hail and damaging gusts.
• Central to eastern Europe: Thunderstorms are expected to be more disorganized due to low CAPE and weak shear.

Meteorological Setup

• A blocking ridge over central Europe continues to weaken and shift east.
• A low-pressure system near Ireland nudges a cold front across western Europe, providing the focus for storm development.
• High moisture content, with precipitable water (PWAT) values of 30–40 mm (1.2–1.6 in), overlaps with warm surface temperatures, creating ideal instability.
• Upper-level waves and weak capping inversion allow for storm initiation over multiple regions, with orographic lifting and diurnal heating playing key roles.

What to Expect

If you’re in or near the Level 2 areas:

• Prepare for rapid weather changes.
• Secure outdoor items and stay indoors during storms.
• Driving may be hazardous due to hail and flash flooding.
• Follow local weather services for real-time warnings and updates.

Summary of Risk Zones (June 14–15, 2025)

Stay Weather-Ready

This setup is volatile and fast-changing. The potential for high-impact severe weather is real, especially in Level 2 zones. Stay connected to trusted local sources and take warnings seriously.