A reinforcing shot of cold air will help a storm system produce the heaviest snow of the season for communities that stretch from Denver through southern Minnesota over the weekend.
Forecast models show the heaviest snowfall will occur in the mountains outside of Denver, but cities such Omaha, Nebraska, and Des Moines, Iowa, will not be immune from the chance of frozen precipitation.
Denver is expected to see 2–5 inches across the metro, which will likely cause some travel problems along major roadways and at the international airport.
The Mile High City typically sees about 4″ of snow during October, meaning that wintry weather is not unheard of around Halloween but is typically on the lighter side.
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Expected snowfall amounts could reach at least the moderate stage of NOAA’s Winter Storm Severity Index.
The index considers expected weather conditions and non-weather data to depict how significant impacts can be for communities.
Minor impacts result in an inconvenience to daily life, while moderate impacts can lead to widespread disruptions.
Where the dividing line meets between the snow and rainfall, a narrow band of precipitation will likely fall as ice.
Counties that could see the heaviest ice accretions are in Kansas, Nebraska and Iowa.
In addition to the threat of ice and snow, tropical moisture streaming northward from the remnants of Hurricane Otis and the Gulf of Mexico will lead to heavy rainfall from the Lone Star State to the Great Lakes.
Temperatures are simply too warm in southern zones for precipitation to fall in the form of ice or snow, meaning the precipitation will fall as rain, and there could be a lot of it.
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Areas that see rainfall from the same storm system could approach 1-3″ of accumulation with the threat of isolated higher amounts.
The threat of precipitation comes after a wave of heavy rainfall that started the workweek for areas from the U.S.-Mexico border through Missouri.
The setup for the heavy rainfall event is fairly similar to what is expected to unfold the upcoming weekend, with a former tropical cyclone’s moisture meeting a frontal boundary draped across the U.S.
Flood Watches were issued for more than 10 million from Texas through Kansas due to the first round of heavy rainfall, with National Weather Service meteorologists closely watching where the weekend’s precipitation will line up.
Any additional precipitation on top of already saturated will likely get the threat of flash flooding high through the weekend and into next week.