November 20, 2024
…Back-to-back powerful Pacific storm systems to impact the West Coast through the end of this week with heavy rain, life-threatening flooding, strong winds, and higher elevation mountain snow… Near blizzard conditions are possible through this evening across the northern Plains… Heavy snow is likely throughout parts of the central Appalachians beginning on Thursday, with a separate burst of snowfall possible across northeast Pennsylvania and neighboring regions of the Northeast Thursday night into Friday…
The National Weather Service’s Weather Prediction Center as “a significant Pacific storm system and strong atmospheric river” continues to move through the northwestern United States Wednesday.
Why It Matters: At least one person is dead, two injured, and hundreds of thousands without power as the strongest atmospheric river to hit California and the Pacific Northwest so far this year makes its way across the northwestern United States. Challenging weather conditions such as heavy rain, flooding, snow and even whiteout conditions will continue to affect many regions of the U.S. through the end of the week.
What are “atmospheric rivers”? The National Oceanic and Atmospheric Administration describes them as “relatively long, narrow regions in the atmosphere – like rivers in the sky – that transport most of the water vapor outside of the tropics,” explaining that strong atmospheric rivers can carry up to “an amount of water vapor roughly equivalent to 7.5 – 15 times the average flow of liquid water at the mouth of the Mississippi River.” When atmospheric rivers reach land, they release water vapor in the form of snow or rain. This particular storm is referred to as a “bomb cyclone,” which describes a cyclone that intensifies rapidly due to a swift drop in air pressure within a very short period of time.
Read More: ‘Bomb cyclone’ kills 1 and knocks out power to over half a million homes across the northwest US (Associated Press)
Image Credit: CIRA
by Stephanie Wagner, based in Florida
