Incessant heavy rain will pile into the Pacific Northwest, USA 🇺🇸 & British Columbia, Canada 🇨🇦 in the next 72 hours due to a significant atmospheric river event.
Flooding & landslides are highly likely. The atmospheric warmth & moisture can be traced all the way to the tropics.
A strong meander in the jet stream allows Alaska to cool under Arctic air but also helps lift Tropical warmth & moisture into British Columbia & the Pacific Northwest.
Notice how the atmospheric moisture aligns and focuses on the same area. This is like nature's firehose. Extreme rain and locally very high freezing levels expected. Meteorologists call this an atmospheric river.
Some refer to this atmospheric river as 'the Pineapple Express'.
You can see the thunderstorms piling into the east coast of Sicily all day, wrapped around a broader circulation from a developing cyclone to the south.
Catania (home to over 500,000 people) was in the bullseye for near constant thunderstorms today.