Central Europe is currently facing the threat of severe flooding and unusually early snowfall in the Alps due to an intense storm battering the region. The storm, named Boris in some areas, has brought tremendous amounts of rain and mountain snow, raising concerns of once-in-a-generation flooding and heavy snow accumulation.

The U.K. Met Office has issued a warning of "extreme rainfall" for central and southern Europe, stating that some rivers may experience events that occur once every hundred years. French and Swiss disaster officials have also cautioned about the potential for catastrophic flood risks in parts of central Europe.

Forecast maps from MétéoSuisse, the government meteorological agency in Switzerland, have drawn similarities to the devastating floods of 2002, which wreaked havoc in the Czech Republic, Austria, and eastern Germany. Already, September snowfall has set new records in parts of the Austrian Alps, while heavy rainfall has triggered flooding in lower elevations of Austria and Slovenia.

The intense precipitation, expected to continue throughout the weekend, has already affected countries such as Slovenia, Austria, Poland, Italy, and Greece. Slovenia, in particular, has experienced 5 to 6 inches of rain and widespread flooding. Austrian officials have urged people to avoid travel, including in the capital city of Vienna.

The incoming storm poses additional risks in areas previously hit by severe flooding, such as Italy and parts of Greece. The saturated soils make these regions susceptible to further flooding. Forecasting engineer Gaétan Heymes warns that this climatological event is completely exceptional, with serious flooding and heavy consequences anticipated due to the high population density in affected areas.

In addition to the heavy rainfall, the storm has brought bitterly cold air from the Arctic region into Europe, resulting in the first widespread frost of the season in the United Kingdom and unusually cold conditions across mainland Europe. The Austrian Alps have witnessed significant snow accumulation, with some locations reporting their first September snowfall on record. Meteorologists have described the current cold spell as unprecedented for this time of the year.

The storm, now cut off from the steering currents of the jet stream, is expected to linger over Europe for several days, continuing to draw moisture from the warm Mediterranean Sea. Austria and the Czech Republic are projected to receive up to a foot of additional rainfall, more than double the usual amount for this time of year. Other areas, including Switzerland, eastern Germany, and parts of Ukraine, are likely to see rainfall totals ranging from 3 to 5 inches.

Meanwhile, heavy snowfall has commenced in the Swiss and Austrian Alps, with the latter expected to receive the most snow. High-elevation locations could see up to 12 inches of snow in just six hours, resulting in storm totals exceeding five feet in some of the highest elevations.

As central Europe braces for the twin threats of severe flooding and early season snowfall, authorities are taking precautions such as releasing water from reservoirs in the Czech Republic in anticipation of heavy rainfall. The region will continue to experience extreme weather conditions until the storm loses intensity and potentially moves west towards the Mediterranean Sea.

With the situation evolving, it is crucial for residents and travelers in affected areas to stay informed and heed the warnings and advisories issued by local authorities.