Over the past week, primarily light to moderate precipitation fell from east Texas northeast through New England. Heavier precipitation amounts of 2 to 6 inches were embedded within the larger precipitation swath, affecting areas from southwest Louisiana to the southern Appalachian Mountains. Heavy precipitation amounts, including mountain snow, fell in the Pacific Northwest and in the central and northern Rocky Mountains. Warmer than normal temperatures also covered most of the continental U.S., with the warmest conditions (compared to normal) taking place in the northern states. In the West, many areas that received significant mountain snow in the past few weeks saw an improvement in drought conditions, while areas that missed out on the snow or still had significant precipitation deficits did not see improvements to their drought depiction. Improvements or degradations in conditions east of the Rocky Mountains were primarily in response to significant precipitation occurring, or lack thereof, over the past several weeks. Degradations made in parts of central and southern Texas also occurred due to high evaporative demand and the associated negative impacts on soil moisture. For more details on changes to this week’s U.S. Drought Monitor depiction, please see the regional paragraphs below.
In Hawaii, recent rainfall led to several improvements in short-term drought and dryness conditions on the Big Island and on Maui. Extreme drought was removed from the northwestern portion of the Big Island this week. In response to rainfall near the Hamakua Coast, the severe drought area near Honokaa shifted away to the south in response to drying conditions farther south. Moderate drought conditions also ceased at South Point. Finally, abnormally dry conditions on Maui retreated to the south. In Alaska, near or above normal short-term precipitation brought an end to the abnormally dry conditions that existed near Anchorage. No changes were made this week to the short-term drought conditions in the Alaska Panhandle. Short-term drought continued in eastern Puerto Rico this week as well.
Moderate and severe short-term drought continued across the southern portion of the Colorado high plains and adjacent southwest Kansas, and moderate short-term drought also continued in south-central Kansas, after a mostly warm and dry week across the High Plains region. Temperatures ranged from 5 to 10 degrees warmer than normal in Kansas to as much as 20 degrees above normal in North Dakota and eastern Montana.
Conditions were mostly dry north of the Ohio River Valley in the Midwest, with the exception of northern Michigan. Temperatures from 5 to 15 degrees above normal also occurred across most of the region. Aside from a continuing area of abnormal dryness in western Indiana, the Midwest remained free of drought or abnormal dryness this week.
Widespread light to moderate precipitation fell across the Northeast over the past week, with some areas receiving over a half inch of precipitation. Warmer than normal temperatures were also common across the region, with most locations between 5 and 15 degrees above normal for the week. Aside from a small area of abnormal dryness in Delaware and Maryland, the region remained free of abnormal dryness or drought this week.
Over the past week, moderate to heavy precipitation occurred in southeast Texas and Louisiana, and from central and southeast Arkansas eastward. The heaviest rain fell from southwest Louisiana to central Mississippi, where amounts ranged from 2 to 6 inches. With warmer than normal temperatures occurring across the region, drought expansion occurred in the parts of northeast Texas, southwest Arkansas, and northwest Louisiana that were missed by the heavier rains. Widespread drought expansion was made from northeast Texas to central and south-central Texas and the Edwards Plateau, as low precipitation this week continued short-term precipitation deficits in these regions. In south Texas, some improvement to drought conditions occurred in areas that received precipitation recently, thus making short-term precipitation deficits less severe or removing them altogether. Moderate drought was removed from the northwest Texas Panhandle, where short-term precipitation deficits had lessened. Moderate and severe drought continued in the Red River Valley in southwest Oklahoma and western north Texas.
Widespread moderate to heavy precipitation occurred in the Southeast this week, where amounts ranged from a half inch to about 4 inches, with the exceptions of the southern Florida Peninsula and coastal portions of South Carolina and North Carolina. Temperatures from 5 to 10 degrees above normal were also common across the region (with the exception of the Florida Peninsula) this week. Due to recent precipitation improving short-term conditions, moderate drought ceased in south Florida.
Heavy precipitation, including mountain show, fell in many of the higher elevation portions of the West this week, with the exception of the Sierra Nevada and mountainous regions of Arizona and New Mexico. Cooler than normal temperatures prevailed in southwest Colorado and eastern Utah and adjacent parts of Arizona and New Mexico, while near or above normal temperatures were commonplace elsewhere in the West. In the Four Corners region, recent precipitation in higher elevation areas improved conditions, such that severe drought lessened to moderate drought around the Chuska Mountains. Lower elevation areas, however, are still suffering from severe precipitation deficits due to the paltry rainfall from the 2019 North American monsoon, and severe drought conditions remained in some of the lower elevation portions of the Four Corners region. Moderate to large snow packs in the San Juan and Sangre de Cristo Ranges in northern New Mexico and southern Colorado led to improvement from severe to moderate drought in the high country, though the San Luis Valley and other lower elevation areas in southern and western Colorado and northern New Mexico remained in severe drought. In the Pacific Northwest, large precipitation amounts, including mountain snow, improved conditions in some of western Washington, leading to the removal of moderate drought around Puget Sound and in southwest Washington. Farther east, mountain snows also occurred in northern Idaho and western Montana, as well as eastern Idaho and the Wyoming, Teton, and Wind River ranges of western Wyoming. Conditions improved as a result of this precipitation in eastern Idaho and western Wyoming. Moderate drought coverage also lessened in the Idaho Panhandle as a result of this heavy precipitation. Meanwhile, short-term moderate drought expanded in coverage in central Idaho, where recent precipitation was not enough to curtail short-term precipitation shortages and snow pack deficits.
A strong storm system is forecast to move across the central and eastern continental U.S. over the next week, delivering 1-3 inches of precipitation, with locally higher amounts, from the south-central U.S. to the Lower Great Lakes region between January 8 and 13. High elevation areas in the West (generally north of the Colorado/New Mexico state line) are forecast to receive precipitation this week as well, with amounts in excess of 3 inches possible in the Cascades and Olympic Range and along the Pacific Coast from northern California into Washington. Primarily warmer than normal temperatures are forecast in the eastern continental U.S. through Tuesday, January 14, while below-normal temperatures will be more common in the West. Temperature swings will occur in the central and southern Great Plains as a series of storm systems and cold fronts progress across the continental U.S., while temperatures in the northern Great Plains will be primarily colder than normal. From Monday, January 13 to Friday, January 17, the National Weather Service Climate Prediction Center is forecasting high probability for warmer than normal temperatures in the southeast half of the continental U.S., and high probability for colder than normal temperatures in the northwest half of the continental U.S. Excepting parts of the southern High Plains and southwest Texas, as well as the Florida Peninsula, the forecast is in favor of above-normal precipitation. In Alaska, above-normal precipitation is forecast from January 13-17, except for southern coastal areas. During this time period, warmer than normal temperatures are forecast for the northern half of Alaska, and colder than normal temperatures are forecast for the southern half of Alaska.