00:33 Flood Aftermath in Braunsbach, Germany This dramatic drone video shows the aftermath of flooding in the town of Braunsbach.

A pair of European countries were swamped this week by an atmospheric phenomenon that was responsible for widespread flooding.

The slow-moving storm system, which at times produced extremely intense and record-breaking rainfall, resulted in major flooding across parts of France and Germany. Portions of northeast France (near the border with Belgium) received six full weeks of rain in just a 24-hour period during the multi-day event.

(MORE: Severe Flooding Traps Schoolchildren, Forces Helicopter Evacuations in Germany )

<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/tmomega.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/tmomega.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/tmomega.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" > An extreme "omega block" pattern set the stage for incredible rainfall totals and massive flooding across parts of France and Germany.

Setup For Extreme Rain

Extreme weather conditions are often produced by a blocking pattern at the jet stream level. The weather over much of the past week across western Europe has been influenced by a phenomenon known as an "omega block."

In this case, a massive high-pressure ridge aloft (bulge in the jet stream) built northward across the eastern North Atlantic and stretched from just east of Greenland to Scandinavia.

Troughs of low pressure (dips in the jet stream) are found on either side of this ridge (forming the Greek Letter Omega: Ω). This particular blocking pattern is more extreme than those that generally occur.

An area of low pressure aloft was trapped beneath the building ridge over western Europe. There was also a corresponding low at the surface. These features are often associated with unsettled weather conditions (with clouds and precipitation). Generally, these systems move along and precipitation events are short-lived.

<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/tmflood.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/tmflood.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/tmflood.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" > A policewoman stands near a car smashed against a building following a severe flash flood on May 30, 2016 in Brensbach, Germany. (Sean Gallup/Getty Images) (Sean Gallup/Getty Images)

Because of this extreme blocking pattern, low pressure remained relatively stationary, so rain persisted over several days. Warm, moist air was pulled northward from the Mediterranean Sea to feed the storm system.

Clusters of slow-moving thunderstorms developed over the past weekend and dumped some incredible amounts of rain, especially across parts of France and Germany.

France:

In Paris, lightning injured 11 people in a park, most of them children.

Meteo France reported a record rainfall for the month of May (over 6 1/2 inches) in the Ile de France region (around Paris).

An entire day's play at the French Open tennis tournament was washed away by rain.

Six weeks worth of rain (over 5 inches) fell in 24 hours near the Belgium border over the past weekend, resulting in severe flooding.

Dozens of hamlets and villages in northern France were under water.

<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/tmsateuro.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/tmsateuro.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/tmsateuro.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" > This infrared satellite image shows the large thunderstorm complex over southern Germany on Sunday.

Germany:

Flooding has resulted in at least four deaths across the nation.

Bavaria was particularly hard-hit by severe flooding, and the district of Rottal-Inn has been declared a natural disaster as the Altbach River flooded the village of Triftern.

Train traffic between Bremen and Hanover was briefly halted after a mudslide.

Divers in the town of Braunsbach were searching underwater for people who could have been trapped in their cars by sudden floods.

Other regions such as North Rhine-Westphalia and Thuringia.

Southern Germany has seen at least 400 percent of its average rainfall over the past week (2-4 inches), according to weather.com meteorologist Jonathan Belles .

Nearly three dozen people were injured after lightning struck a children's soccer match Saturday in Hoppstädten.

The current pattern will slowly break down over the next couple of days. Although rain will not be as persistent, or intense, periods of rain and thunderstorms will continue throughout the region until the end of the week. Localized flooding remains a possibility, however.

MORE ON WEATHER.COM: Severe Flooding in Germany