Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 300 AM EST Sat Nov 07 2020 Valid 12Z Sat Nov 07 2020 - 12Z Mon Nov 09 2020 ...Heavy snow to develop over parts of the Sierra, Rockies and Northern Plains... ...Record or near record warmth continues from Northern Plains to Midwest and Northeast/Mid-Atlantic; record cold likely across California and Great Basin... ...Heavy rainfall and strong wind to impact southern Florida as Tropical Storm Eta crosses the Keys... A potent upper-level low will drive much of the weather impacts across the western U.S. this weekend. A deep area of surface low pressure will generate heavy snow over the Sierra later today before spreading across Rockies this evening and on Sunday. Snow totals of up to a foot are possible over the Sierra while much higher values around 2 feet are more likely over the Rockies and Northern Plains. Ice impacts will be marginal with this system. A very cold air mass will filter into the West behind this powerful system as high pressure settles over the Pacific Northwest. Temperatures will be cold enough this weekend to potentially break records, especially across California and the Great Basin where highs are expected to be between 20-30 degrees below average. Cold air will also filter into the Northern Rockies where highs may also be between 20-30 degrees below average on Sunday. Meanwhile, Record warmth will impact the Upper Midwest and Northeast/Mid-Atlantic this weekend. A dome of high pressure, currently stationed over the eastern half of the country, will expand over the region leading to widespread temperature records being broken. The anomalous heat will be on the order of 30-40 degrees above average for parts of the Northern Plains and Upper Midwest today, and contracting into the latter tomorrow. The potential for record breaking temperatures continues over the Midwest and Northeast tomorrow. Tropical moisture will stream northward today ahead of Tropical Storm Eta Kebede Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php