2027 Lithuanian Tornado Disaster

The 2027 Lithuanian Tornado Disaster (also known as the Black Friday of 2027 to Lithuanians) was a catastrophic F5-rated tornado that struck multiple cities in Northeastern Europe, most notably Vilnius at its peak intensity, and became the costliest and deadliest European tornado on record, resulting in over $2.9 billion in damages and 1784 deaths, with its extremely long track of 262 km (163 miles). This tornado was part of a larger tornado outbreak, that produced 17 tornadoes over the territories of Russia, Poland, Lithuania, and Belarus, between May 7th and May 9th of 2027.

The tornado touched down 15 kilometres west-southwest of the city of Suwałki in Podlaskie Voivodeship, Poland, at 07:29 EEST (04:29 UTC), and stayed on the ground for 3 hours and 18 minutes over a 262 km (163 mile) long path, crossing through three countries, and numerous cities, including Vilnius. The tornado's peak width occured in Belarus while it was weakening, and was 3.5 kilometres (2.2 miles) wide. Its peak winds occurred just before it struck central Vilnius, at 9:27 AM EEST (6:27 AM UTC). It tracked through areas unprepared for tornadoes such as this, and overall, caused devastating damage, and a high death count highly influenced by the lack of tornado situational training and tornado shelters.

Meteorological synopsis
In early May, a warm dry front from southern Europe collided with a cool moist front from Scandinavia. The collision of fronts resulted in conditions favorable for thunderstorm formation, and extremely high CAPE values of 4000 - 5000 J/kg with high upper shear meant that there was a high chance of supercell formation.

The storm system that eventually resulted in the outbreak started forming late on May 6th, over the southern Baltic Sea, and moved generally east-northeast until it died out late on May 9th over northeastern Belarus and southwestern Russia. Probabilities of tornadic formation were not issued by any official weather agency, however unofficial agencies issued a peak tornadic formation probability of 60%.

Storm development and track
The thunderstorm that eventually produced the tornado developed at around 4:30 AM EEST, south of Ilawa city in the Warmian-Masurian Voivodeship. It moved generally northeast, developing pronounced rotation on radar, and crossed Poland for the next 3 hours. Over these 3 hours, the thunderstorm became a supercell, and eventually storm spotters reported a large wall cloud and a rear-flank downdraft. TORRO reported the thunderstorm to be a "certain tornado producing thunderstorm" as it had very favorable conditions to do so.

At 7:29 AM EEST (4:29 AM UTC), the tornado touched down in Podlaskie Voivodeship, 15 kilometres west-southwest of the city of Suwałki, and became the first confirmed tornado of the outbreak sequence. The 250-metre wide stovepipe F0 tornado quickly intensified into an F1 and moved through southern Suwałki city, causing moderate damage. After moving through Suwałki, the tornado weakened back to an F0 while starting to widen. At around 8 AM, north of Sejny, the tornado began producing F1 damage again, and F2 damage was found almost exactly on the Polish - Lithuanian border. After crossing into Lithuania, the now 1-kilometre wide F2 tornado passed through the town of Lazdijai, severely damaging several Soviet-era apartment blocks. After that, the tornado became an F3 and passed over the lakes Dusia and Metelys. At around 8:35 AM, the city of Alytus was struck by the F3 wedge tornado, and suffered severe damage, with some apartment blocks suffering partial collapse, and numerous private homes being completely destroyed. Up to that point, the tornado had caused $315 million in damages, and resulted in 127 deaths.

After the reports of an extremely damaging tornado to the emergency services reached well into the tens of thousands, civil defense sirens were sounded all over Vilnius county, and an official warning, the first of its kind, was broadcasted over television, radio, and text messages. Overall, it is estimated that at least 700 thousand people received the warning, greatly reducing the eventual death and injury count. As the tornado crossed over plains, it briefly weakened to an F2, but by 9 AM had intensified to an F4 wedge tornado. At 9:10 AM, while the tornado was affecting the A16 highway with its very edge, the first F5 damages were recorded, with severe ground scouring and homes completely swept away. At around 9:15 AM, the edge of the tornado affected the city of Trakai, while the tornado weakened to an F4 while crossing the A16 highway. 9 deaths and $20 million in damages were recorded in the general area.