Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 155 PM EST Sat Nov 9 2019 Valid 00Z Sun Nov 10 2019 - 00Z Tue Nov 12 2019 ...The next surge of arctic air is poised to bring the coldest temperatures so far this season for the north-central U.S. by Sunday... The second Arctic intrusion in less than a week is now arriving across the northern Plains and Upper Midwest Saturday afternoon, with a pronounced cold front quickly dropping southeastward along and east of the Rockies. This episode of cold weather will have an anomalously strong surface high with its origins over the Arctic Ocean, and may come close to some monthly high pressure records for the northern Plains with levels near 1045 mb expected. By Monday evening, the front is expected to reach northern Mexico and the Appalachians with an abrupt drop in temperatures behind it, leading to some impressive 24-hour temperature changes on the order of 30 to 40+ degrees possible! It will feel more like the middle of January for the beginning of the week, with numerous record low maximum temperatures possible from the central Plains to the Great Lakes on Monday. Snow is expected for much of Montana and the western Dakotas through Sunday evening owing to upslope flow behind the front along with a shortwave passage aloft. Winter weather advisories and some winter storm warnings are in effect, mainly for central and eastern Montana where snowfall totals in the 4 to 8 inch range could be realized. Lake effect snow is also expected to increase on Monday for areas downwind of Lake Superior and Lake Michigan. Another mild day can be expected on Sunday from Texas to the Ohio Valley ahead of the front, and the mild weather lasts through Monday for the Southeast U.S. to southern New England before major changes ensue. Showers are likely with the passage of the front, with the heaviest rainfall over Arkansas with amounts approaching one inch. Locations west of the Rockies should be spared from this Arctic airmass, with near to above average temperatures expected from the Desert Southwest to the Pacific Northwest. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php