US Day 3-7 Hazards Outlook NWS Weather Prediction Center College Park MD 208 PM EST Wed Feb 19 2020 Valid Saturday February 22 2020 - Wednesday February 26 2020 Hazards: - Heavy precipitation across portions of the Pacific Northwest, Sun-Mon, Feb 23-Feb 24. - Heavy rain across portions of the Central Plains, the Lower Mississippi Valley, the Tennessee Valley, the Middle Mississippi Valley, the Southern Plains, and the Ohio Valley, Sun-Mon, Feb 23-Feb 24. - Heavy rain across portions of the Southeast, the Mid-Atlantic, the Southern Appalachians, and the Tennessee Valley, Mon-Wed, Feb 24-Feb 26. - Heavy snow across portions of the Pacific Northwest, the Northern Rockies, and the Northern Great Basin, Sun-Mon, Feb 23-Feb 24. - Heavy snow across portions of the Central Plains, the Central Rockies, the Central Great Basin, the Southern Rockies, the Southern Plains, and the Southwest, Sun, Feb 23. - Heavy snow across portions of the Central Plains, the Middle Mississippi Valley, the Upper Mississippi Valley, and the Northern Plains, Tue-Wed, Feb 25-Feb 26. - Flooding occurring or imminent across portions of the Lower Mississippi Valley, the Tennessee Valley, the Middle Mississippi Valley, the Mid-Atlantic, the Southeast, and the Ohio Valley. - Much below normal temperatures across portions of the Central Plains, the Central Rockies, the Central Great Basin, the Northern Plains, the Northern Rockies, the Southern Rockies, the Northern Great Basin, the Southern Plains, and the Southwest, Tue-Wed, Feb 25-Feb 26. - Much below normal temperatures across portions of the Southeast, the Mid-Atlantic, the Lower Mississippi Valley, the Southern Appalachians, and the Tennessee Valley, Sat, Feb 22. - Heavy precipitation across portions of the Alaska Panhandle and mainland Alaska, Tue-Wed, Feb 25-Feb 26. - High winds across portions of mainland Alaska, Tue-Wed, Feb 25-Feb 26. - Much below normal temperatures across portions of mainland Alaska, Sat, Feb 22. Detailed Summary: The medium range period (Saturday, Feb. 22 to Wednesday, Feb. 26) will feature a semi-active pattern as two systems enter the western U.S. and traverse across the country. The first area of concern will come from a cut off low entering the Southwest. This will bring areas of rain and heavy mountain snow to portions of Arizona and the southern Rockies beginning on Saturday and lasting through the weekend. By Sunday, an area of surface low pressure is forecast to develop across the Southern Plains. Heavy rain will be possible ahead of this low and along an associated warm front on Sunday and Monday. Total rainfall amounts of 1 to 2 inches could lead to flooding concerns from the Central Plains to the Middle Mississippi Valley. This system is forecast to exit the East Coast by Tuesday, with the possibility of light snowfall across the Interior Northeast and Great Lakes. Heavy rain will also be possible across the Southeast beginning on Monday, with showers lingering through Wednesday ahead of the next system. The next area of unsettled weather to enter the U.S. will approach the Pacific Northwest on Sunday. Heavy coastal rain and mountain snow is likely across the Olympic and Cascade mountain ranges on Sunday and Monday. This heavy snow will also impact portions of the northern Great Basin and Northern Rockies during this time frame. Uncertainty increases with this system by Tuesday as it enters the central United States and interacts with the earlier mentioned energy from the Southwest. The heavy snow area on the hazards chart across the Upper Midwest was deeply contemplated due to widespread model outputs, but enough ensemble support lead to adding the highlighted area. Well below normal temperatures, thanks to a large area of arctic high pressure, are forecast across portions of the East to start the medium range period. Cold temperatures will be found across the Southeast Saturday morning. Here, temperatures could reach below freezing as far south and northern Florida. Considering reports of trees and plants getting off to an early bloom in this area, a hard freeze could pose issues. Across the Rockies and High Plains, an upper-level trough is expected to set up over the region and lead to temperatures well below average for this time of year by Tuesday. These cold temperatures could linger later into next week. Hazardous weather across Alaska will be confined to the southern coastline. On Tuesday, a potent low pressure system is forecast to bring gusty winds and heavy precipitation here. Meanwhile, temperatures well below normal are expected on Saturday across central and western portions of the state. This cold air is forecast to moderate by Sunday. Snell