U.S. Weather/Crop Progress
U.S. Drought Monitor Weather Forecast: The 5-day Quantitative Precipitation Forecast (QPF) from the NWS Weather Prediction Center (December 31, 2020 – January 4, 2021) depicted heavy precipitation along the West Coast, from northern California northward to Vancouver Island, associated with a series of potent storm systems. Across the eastern CONUS, an active storm track favors widespread precipitation totals exceeding an inch from the Southern Great Plains eastward and northeastward to the Atlantic Coast, excluding the Florida Peninsula. This is in addition to precipitation falling in the first 2 days of the period across many of these same areas. Heavier precipitation (more than 3 inches) is likely from eastern Texas to the Tennessee Valley over the next 5 days, and west of the Big Bend area in Florida. Little to no precipitation is expected from the Four Corners Region to the Northern Plains and Upper Midwest. A southern shift in the western storm track is expected to occur toward day 5, leading to below-normal temperatures across the southwestern CONUS. The lack of seasonal snowpack is expected to remain intact across the Northern Plains, contributing to large positive temperature anomalies. In the eastern CONUS, mean southerly flow is expected to dominate, keeping temperatures anywhere from 5°F to 10°F above normal.
The 6-10-day CPC extended range outlook (January 5-9, 2021) favored amplified mean troughing from Alaska southeastward to the southwestern CONUS, indicating a southward shift in the storm track along the West Coast. Ridging is favored to dominate much of the eastern CONUS, with the highest mean mid-level positive geopotential height anomalies over the Great Lakes and Northeast. Below-normal temperatures and precipitation are favored over western and northern Mainland Alaska, respectively, while odds tilt toward above-normal precipitation along the southern Alaska coast. Increased odds of below-normal temperatures in the southwest CONUS are associated with below-normal mid-level heights. Ahead of the mean trough over the West, above-normal precipitation is favored over the Central Plains and western Corn Belt. Additionally, southerly to southwesterly mean flow enhances odds of above-normal temperatures across much of the eastern two-thirds of the CONUS. With the amplified troughing across the western CONUS, enhanced odds of above-normal precipitation extend along the entire West Coast and into the Great Basin and Four Corners region. Probabilities of below-normal precipitation are increased for the Northeast, underneath positive mean mid-level height anomalies, and in Florida and southeastern Georgia, as any passing frontal boundaries are expected to remain farther north.
Follow this link to view current U.S. and international weather patterns and future outlook: Weather and Crop Bulletin.