Storm Bora brings days of flooding to Greece, with more rain ahead

A lumbering low-pressure system over the central Mediterranean Sea has been dousing Greece in waves of torrential rainfall over recent days, a weather pattern reminiscent of one that wrought severe flooding in Spain in October.

Vehicles were swept away on streets that turned to rivers on the island of Rhodes as December got underway. The day before, the island of Lemnos in northern Greece was struck in a similar fashion. Other spots have been cut off by washed-out roads and landslides.

Both islands are under states of emergency due to widespread damage, numerous water rescues and with local reports of deaths and injuries.

A trapped area of cold air and spin overhead, cut off from the jet stream flow and feeding off the warm Mediterranean Sea, is the primary culprit for the downpours. Added atmospheric moisture from human-caused climate change and other factors are also to blame.

The storm - named Bora in Greece, where the word means wind - will continue to plague parts of the area into midweek, with additional rain likely right on its heels. A potentially volatile pattern will persist into next week in the region and additional portions of the continent.

Widespread impact

About 135 miles to the northwest of Athens, in northern Greece on a peninsula jutting into the Aegean Sea, the Halkidiki region faced extensive destruction. According to local media, several villages suffered severe flooding; roads were washed out and a bridge had collapsed.

One man was killed there trying to navigate landslides and floods, his vehicle plunging into water, where he succumbed to hypothermia, according to reports. Local officials warned of prohibited travel corridors, widespread damage and also reported water rescues.

On Lemnos, in the northern Aegean Sea, two men were killed during the storm, though their deaths were unrelated to flooding, according to France 24.

The island was struck by widespread flooding, especially in key agricultural areas.
Rhodes, a favorite with tourists, sits well southeast of those locations, 275 miles southeast of Athens, or just off the southwest coast of Turkey. Travelers and residents there watched rapids overtake streets after six to 12 inches of rain fell in only 12 to 16 hours.

There, dozens were evacuated to higher ground in and around the hard-hit city of Ialysos. In addition to flooded businesses, washed-out roads and cars piled high after water levels receded, residents were displaced and some homes were lost.

More rain to come

Additional rainfall is forecast through midweek from the same trapped system. And some of the rain could be torrential, since the setup has not changed too much.

With any further rain comes the potential for more flooding in the eastern Greek isles, including around Rhodes. This wave of rain will probably continue to shift eastward through Tuesday as another zone of enhanced moisture crosses the Ionian Sea between Italy and Greece into midweek.

Flooding may become pronounced again heading into the late week and weekend, as rounds of heavy rain within the next concentrated wave slowly drift by.

Warm water and a similar tale

Water temperatures are above to well above average across almost all of the Mediterranean Sea.

Unusual warmth in the ocean boosts the intensity of large-scale storms and provides a conduit for excessive rainfall to pound a specific region.

As in the floods that hit Valencia and other portions of Spain beginning in October, nearby waters are among the toastiest in the region. Slow-moving weather patterns lead to stalled frontal zones that can wring out incredible moisture over a short period.

While oceans were rapidly warmed during last winter’s El Niño event, the steady march upward is a result of climate change, and the sustained warmth a year after the El Niño is concerning some scientists.

Amid a changing climate, Greece and the Mediterranean have also witnessed intense heat, crippling drought, raging wildfires and other floods in recent years.

There could be more ahead

With the present storm weakening over time, a weather pattern featuring immense differences between high and low pressure is forecast to continue in Europe.

By the weekend, a powerful storm is forecast to cross the United Kingdom and squeeze southward between anchored high-pressure areas to its west and east. The storm will bound across central Europe, squashed south by a flexing high pressure zone from Greenland to the Nordic countries. Current suggestions into next week are that stormier-than-normal conditions may again be prevalent from near Spain to the Mediterranean.