US Day 3-7 Hazards Outlook NWS Weather Prediction Center College Park MD 338 PM EST Thu Jan 17 2019 Valid Sunday January 20 2019 - Thursday January 24 2019 Hazards: Heavy precipitation across portions of the Northeast, Thu, Jan 24. Heavy rain across portions of the Southeast, the Mid-Atlantic, the Southern Appalachians, and the Tennessee Valley, Wed-Thu, Jan 23-Jan 24. Heavy snow across portions of the Northeast, the Central Appalachians, the Pacific Northwest, the Northern Great Basin, the Mid-Atlantic, California, the Central Great Basin, the Great Lakes, and the Southwest, Sun-Mon, Jan 20-Jan 21. Heavy snow across portions of the Great Lakes, the Middle Mississippi Valley, the Pacific Northwest, the Upper Mississippi Valley, and the Northern Great Basin, Tue-Wed, Jan 22-Jan 23. Heavy snow across portions of the Northern Rockies and the Northern Great Basin, Sun, Jan 20. and Tue-Wed, Jan 22-Jan 23. Heavy snow across portions of the Central Rockies, the Central Great Basin, the Northern Rockies, and the Northern Great Basin, Wed-Thu, Jan 23-Jan 24. Heavy snow across portions of the Southern Rockies, the Central Rockies, the Central Great Basin, and the Southwest, Mon-Tue, Jan 21-Jan 22. Flooding possible across portions of the Mid-Atlantic and the Northeast. Flooding occurring or imminent across portions of the Southeast, the Lower Mississippi Valley, and the Southern Plains. High winds across portions of the Mid-Atlantic and the Northeast, Sun-Mon, Jan 20-Jan 21. Much below normal temperatures across portions of the Northeast, the Central Appalachians, the Middle Mississippi Valley, the Mid-Atlantic, the Upper Mississippi Valley, the Great Lakes, and the Ohio Valley, Mon-Tue, Jan 21-Jan 22. Heavy precipitation across portions of the Alaska Panhandle and mainland Alaska, Tue-Thu, Jan 22-Jan 24. Detailed Summary: Deep low pressure over the Mid-Atlantic will move northeastward to the Canadian Maritimes by Tuesday. The system will produce heavy snow over parts of the Northeast on Sunday. In the wake of the low pressure, cold air will move into the Western Ohio Valley as a cold area of high pressure moves southeastward from South-Central Canada into the Great Lakes/Ohio Valley on Monday that will move eastward to the Mid-Atlantic by Tuesday. The cold high pressure will producing an area of much below normal temperatures from the Ohio Valley eastward to New England on Monday into Tuesday. In addition, high wind will also accompany the low over the Mid-Atlantic Coast on Sunday. A second area of low pressure over the Central Rockies will move northeastward to New England by Thursday. The system will produce heavy snow over parts of the Central Rockies on Monday. As the low moves eastward, another area of heavy snow will develop over parts of the Great Lakes/Western Ohio Valley on Tuesday. The storm will also produce a third area of heavy snow over parts of the Northeast on Wednesday into Thursday. An area of heavy precipitation will develop over parts of Southern New England on Thursday with regions of rain and snow. Additionally, a narrow region of heavy rain of one inch or more will develop over parts of the Central Gulf Coast into the Southeast. A front moving inland over the West Coast will aid in producing heavy snow over the Sierras into the Cascades on Sunday. The associated upper-level energy will aid in producing areas of heavy snow over parts of Idaho on Sunday. Upslope flow will aid in producing an area of heavy snow over parts of Idaho on Tuesday. Upper-level energy and onshore flow will aid in producing heavy snow over parts of the Northern Cascades on Tuesday into Wednesday. Furthermore, another region of upper-level energy over the North Pacific on Tuesday will move southeastward to the Central Rockies by Thursday will aid in producing heavy snow over parts of the Northern Rockies on Wednesday into Thursday. Over Alaska, multiple areas of low pressure will impact the Alaska Peninsula and the Gulf of Alaska streaming moisture in to Kodiak Island and Kenai Peninsula eastward to Yakutat will have heavy precipitation in the form of lower elevation rain and snow from Tuesday into Thursday. Ziegenfelder