US Day 3-7 Hazards Outlook NWS Weather Prediction Center College Park MD 331 PM EST Tue Feb 19 2019 Valid Friday February 22 2019 - Tuesday February 26 2019 Hazards: Heavy rain across portions of California and the Pacific Northwest, Tue, Feb 26. Heavy rain across portions of the Lower Mississippi Valley, the Central Appalachians, the Tennessee Valley, the Middle Mississippi Valley, the Mid-Atlantic, the Southern Appalachians, the Southeast, the Southern Plains, and the Ohio Valley, Fri-Sun, Feb 22-Feb 24. Heavy rain across portions of the Southeast, the Mid-Atlantic, the Lower Mississippi Valley, the Southern Appalachians, and the Tennessee Valley, Mon-Tue, Feb 25-Feb 26. Heavy snow across portions of the Pacific Northwest and the Northern Great Basin, Fri-Sun, Feb 22-Feb 24. Heavy snow across portions of the Southern Rockies, the Central Rockies, the Central Great Basin, and the Southwest, Fri-Sat, Feb 22-Feb 23. Heavy snow across portions of the Central Plains, the Middle Mississippi Valley, the Great Lakes, the Upper Mississippi Valley, and the Northern Plains, Sat-Sun, Feb 23-Feb 24. Heavy snow across portions of the Northeast, Sun-Mon, Feb 24-Feb 25. Severe weather across portions of the Middle Mississippi Valley, the Lower Mississippi Valley, the Southern Plains, the Ohio Valley, and the Tennessee Valley, Sat, Feb 23. Flooding possible across portions of the Lower Mississippi Valley, the Tennessee Valley, the Mid-Atlantic, the Southern Appalachians, the Southeast, and the Ohio Valley. Flooding occurring or imminent across portions of the Middle Mississippi Valley, the Lower Mississippi Valley, the Ohio Valley, and the Tennessee Valley. Flooding likely across portions of the Lower Mississippi Valley, the Ohio Valley, and the Tennessee Valley. High winds across portions of the Central Plains, the Northeast, the Central Appalachians, the Northern Plains, the Middle Mississippi Valley, the Mid-Atlantic, the Upper Mississippi Valley, the Great Lakes, and the Ohio Valley, Sat-Mon, Feb 23-Feb 25. 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, California, the Northern Great Basin, the Upper Mississippi Valley, the Pacific Northwest, and the Southwest, Fri-Tue, Feb 22-Feb 26. Enhanced wildfire risk across portions of the the Southern Plains, Sat-Sun, Feb 23-Feb 24. Heavy precipitation across portions of mainland Alaska and the Aleutians, Sat-Sun, Feb 23-Feb 24. Heavy precipitation across portions of mainland Alaska, Sun-Tue, Feb 24-Feb 26. Heavy precipitation across portions of the Aleutians, Fri-Sat, Feb 22-Feb 23. High winds across portions of mainland Alaska, Fri, Feb 22. High winds across portions of the Aleutians, Fri-Mon, Feb 22-Feb 25. Much above normal temperatures across portions of mainland Alaska, Sun-Tue, Feb 24-Feb 26. High significant wave heights for coastal portions of the Aleutians, Fri-Mon, Feb 22-Feb 25. Detailed Summary: A storm over the four corners region of the West will move northeastward to the Great Lakes by Sunday and move into Maine by Monday. The storm will then move into the Canadian Maritimes by Tuesday. The system will produce an area of heavy snow over parts of the Southwest into parts of the Central/Southern Plains on Friday. As the storm moves into the Great Lakes, an area of heavy snow will develop from parts of the Central Plains into parts of the Upper/Middle Mississippi Valley and into parts of the Upper Great Lakes on Saturday. By Sunday, the heavy snow will move into parts of the Northern Maine. As the storm moves out of the Rockies, moisture from the Gulf of Mexico will flow northward and overrun the associated front producing and area of heavy rain greater than one inch over parts of the Lower Mississippi/Tennessee Valleys into the Ohio Valley/Central Appalachians and parts of the Mid-Atlantic on Friday into Sunday. The axis of heavy rain will move a little farther south on Monday into Tuesday with the area of heavy rain greater than one inch will extend from parts of the Central Gulf Coast/Tennessee Valley into the Southeast/Southern Appalachians. Additionally, as the storm moves from the Central Plains to the Great Lakes into the Northeast, the depth of the surface low and the pressure gradient will aid in producing an area of high wind from parts of the Central Plains and Upper/Middle Mississippi Valley into parts of the Upper/Lower Great Lakes/Ohio Valley into parts of the Northern Mid-Atlantic from Saturday into Monday. In addition, a front will move into the Pacific Northwest on Friday into Sunday. The system will produce heavy snow over the Cascades on Friday into Sunday as well. Onshore flow off the North Pacific will aid in producing an area of heavy rain greater than one inch on Tuesday. The upper-level pattern of a persistent deep upper-level trough over the West and cold attic high pressure moving over the plains will aid in producing a large area of much below normal temperatures from the interior West Coast to the Northern/Central Plains and as far south as the Southwest/Southern Rockies Friday through Tuesday. For Alaska, a storm over the North Pacific will move into the Bering Sea on Saturday into Sunday followed by another storm on Monday into Tuesday that will aid in producing an area of high wind of 50 knots or greater and significant waves of 20 feet or greater from Friday into Monday. A plume of moisture will move across the Aleutians on Friday that will move to the Alaska Peninsula on Sunday into Tuesday that will produce a region of heavy precipitation that will move eastward with the plume of moisture from Friday into Tuesday. The plume of moisture will move over parts of the Western Coast of the Alaska Mainland producing an area of heavy precipitation on Saturday into Sunday. The persistent upper-level ridging over the North Pacific will extend well into Northern Alaska as an upper-level high develops over Northern Alaska. Temperatures will be well above normal over Northern Alaska from Saturday into Tuesday. Ziegenfelder