From 12–16 September 2024, Vb-type cyclone ‘Boris’ brought persistent heavy precipitation and strong winds to Central and Eastern Europe. Northeastern Austria was particularly affected, with several pre-Alpine regions exceeding 300 mm in five days, and numerous station records broken. Using station and gridded observations, we benchmark five-day total precipitation against historical extremes and estimate return periods. We find that 6.6 % of Austria experienced totals at least 50 % above previous records, with maxima around 162 % higher. Several stations exhibit return periods of hundreds of years. The event is unprecedented in the Austrian observational record, underscoring its exceptional severity and climatological rarity.