Severe Bura/Bora winds over the Adriatic sea and intense sea-effect snowfall across S-CNTRL Italy – January 6-7, 2017

It has been snowing in parts of central Italy for almost 3 days now as strong and persisting NE-erlies are advecting arctic cold airmass over the Adriatic and Tyrrhenian seas, resulting in robust sea-efect snowfall and stau/orographic precipitation ashore. Additionally, extremely severe Bura/Bora winds are on going along the E Adriatic coastal areas, wind gusts up to 220 km/h have been reported! Bura/Bora is a catabatic wind blowing from elevated inland areas (Velebit, Lika) over the Slovenian and Croatian coast of the Adriatic sea. The higher the temperature and pressure difference / gradient between higher inland terrain and the sea is present, the more severe winds are. There was around 15-18°C difference across the mountain range today, Saturday, January 7 producing a very favourable environment for intense Bura/Bora winds. Bura often exceeds 200 km/h in the Velebit and Kvarner region in Croatia and peak values from the most severe past events were approaching 300 km/h. This makes the Bura/Bora winds some of the strongest on Earth.

Below is the latest outlook for the area affected by excessive snowfall until Sunday as well as the areas under the powerful Bora in E Adriatic sea:

According to the Croatian national weather service (DHMZ) data, the strongest wind gusts on Friday (Jan 6) were: Most Pag (Pag Bridge) 218 km/h, Jasenice 196 km/h, Zavižan 148 km/h, Dubrovnik 143 km/h, Split 130 km/h.

Severe, up to nearly hurricane-force Bura/Bora winds are blowing over the Adriatic sea coast in Croatia, gusting over 150-160 km/h. The same wind blowing across the warmer Adriatic sea is causing intense sea-effect snowfall and locally blizzard conditions in parts of central and southern Italy, most notably Abruzzo.

Satellite imagery shows the ongoing sea-effect over the Adriatic and Tyyrhenian seas, with convective cells forming above the seas and forming the so-called cloud streets.

Intense snowfall and blizzard conditions are being reported across CNTRL-S Apennine peninsula and Sicily. Below are some videos reported by our readers and reporters (updated regularly):