Almost all the U.S. experienced a cooler-than-normal week, with only a handful of areas being above normal. The coolest readings were in the Rocky Mountains, where departures were up to 15 degrees below normal, while the warmest areas were in central and northern California, New England, and south Florida, where departures were a few degrees above normal. Precipitation was also greatest in the Rocky Mountains where the upper elevations recorded a good week of snow. Precipitation was widely scattered throughout the Southeast where some portions of north Florida had over 200% of normal precipitation for the week. At the end of the period, a cold air mass settled in over the eastern two-thirds of the country, bringing cold air all the way down into the deep South with winter storms along the Gulf Coast. There are multiple regions that have had several weeks of dryness with minimal precipitation. Even though it is winter, and drought tends to move slower due to reduction of demand, these areas will continue to be monitored for degradation if the pattern continues and the data support it.
Northeast
Precipitation for the week was scattered across the entire region, with some areas of Pennsylvania, New Jersey, Maine, and New York picking up over 100% of normal precipitation for the week, mainly as a wintery mix to all snow. Temperatures were cooler than normal with departures of 10-15 degrees below normal in portions of West Virginia and Pennsylvania. Only the northern extents of New England were warmer than normal with departures of 2-5 degrees above normal. Most of the region’s drought status remained unchanged this week. There was a slight expansion of severe drought in portions of southern Maryland and northern Virginia, and some moderate drought expanded over southern Virginia.
Southeast
Cooler-than-normal temperatures dominated the region with most locations being 5-10 degrees below normal for the week. The only outlier was most of south Florida with up to 5 degrees above normal. A few areas of rain moved through the region from central Alabama into central South Carolina that helped to dampen up conditions, and along with the cooler-than-normal temperatures, kept most of the region from having changes on the map this week. The biggest rains were over north Florida, where up to 400% of normal precipitation occurred this week. Other areas remained dry. As some areas have been consistently dry for much of the winter, abnormally dry conditions expanded over western North Carolina and moderate drought expanded over central North Carolina, while moderate drought expanded over northern areas of South Carolina. Abnormally dry conditions and moderate drought improved over north Florida, while moderate drought expanded over much of the western areas of Florida. Abnormally dry conditions also improved this week over some areas of central and eastern Alabama.
South
Temperatures were cooler than normal for the region this week with most areas 5-10 degrees below normal. It was mostly a dry week throughout the region with only areas of southern Texas recording above-normal precipitation. Some areas are pushing 60 or more days without any significant precipitation in portions of Oklahoma and Texas, but as it is climatologically the driest time of the year for some of these areas, drought degradation has been slow. Changes this week included an expansion of abnormally dry conditions over extreme northwest Arkansas and central Texas. Moderate drought also expanded over portions of central Texas due to reports of crop losses due to lack of soil moisture in the region. Extreme drought expanded along the Big Bend of Texas where hydrological indicators are supporting the expansion. Some improvements to the severe and extreme drought were made in middle Tennessee, but abnormally dry conditions were expanded in the southwest portion of the state.
Midwest
It was a fairly dry week over much of the region, with the greatest precipitation occurring from southeastern Missouri to southern Illinois. The cold air mass coming out of Canada impacted temperatures throughout the entire region. Temperatures were 8-12 degrees below normal from northern Missouri through much of Illinois and into Indiana, Ohio, and Kentucky. Almost all the rest of the region was at least 4-8 degrees below normal. The drought status remained unchanged for most of the area, with only a slight reduction of the abnormally dry conditions in portions of northern Illinois and Indiana.
High Plains
Some of the coldest air of the year settled into the region over the last week. Departures from normal temperatures were 12-15 degrees below normal in portions of Wyoming, South Dakota, and Colorado, and into Kansas and Nebraska. Dry conditions dominated the region with only portions of southwest Kansas and the Plains of Wyoming and Colorado recording precipitation. December and January are the driest months of the year and deficits are accumulating with little to no precipitation over the last several weeks. Conditions will continue to be monitored for further degradation in the region.
West
It was a dry week for most of the region outside of the accumulated snow in the Rocky Mountains and into northern New Mexico. Temperatures were mainly cooler than normal over the region, with portions of the Rocky Mountains 12-15 degrees below normal for the week. Portions of northern and central California were near normal to slightly above normal for temperatures this week. The abysmal start to the water year continues over much of southern California, southern Nevada and Utah, and into Arizona and New Mexico. Most of the managed water systems are fine in the region after two consecutive wet winters, but the short-term drought indicators for the current water year are highlighting the significant short-term drought in the Southwest into southern California. Degradation to drought status continued this week with drought expanding and intensifying over much of southern California. Abnormally dry conditions expanded over much of western New Mexico and northeastern Arizona, with extreme drought expanding over western Arizona and severe drought expanding over southwest Utah. The recent wet pattern was enough to remove the remaining abnormally dry conditions out of central Oregon while the recent snows in the Rocky Mountains allowed for some drought intensity reductions in northern Colorado and with western and north central Wyoming. Colorado had moderate drought expand in the south, with a new pocket of abnormally dry conditions added in the Southwest.
Caribbean
No changes were made to Puerto Rico.
The U.S. Virgin Islands remained free of drought or abnormal dryness this week. On St. Croix, it was a relatively dry week, as the highest rainfall amount reported was 0.19 inches, though the relative dryness of the last month is still outweighed by the wetter 3-month and longer period. On St. Thomas, groundwater levels continued to drop this week while reported rainfall amounts varied from 0.29 to 0.41 inches. On St. John, reported rainfall amounts varied from 0.69 to 0.86 inches while groundwater levels continued to drop there as well.
Pacific
No changes were made to Alaska
No changes were made to Hawaii.
American Samoa remained free of drought or abnormal dryness this week. Reported rainfall totals ranged from 0.67 inches at Toa Ridge to 0.97 inches at Pago Pago to 2.12 inches at Siufaga Ridge.
Just under an inch of rain fell this week at Koror, and Palau remained free of drought or abnormal dryness this week.
Another dry week occurred on Guam, where only 0.14 inches of rain were reported. No impacts from the recent dryness appear to be occurring yet, and no abnormal dryness or drought has developed yet. Only 0.41 inches of rain were reported on Rota, marking the fourth consecutive week with less than 1 inch of rain, and short-term abnormal dryness continued. On Saipan, 0.52 inches of rain were reported. Given mostly drier weather in December and the very dry start to January, short-term severe drought has developed on Saipan.
On Kwajalein, 0.16 inches of rain have been reported this week, with 3 days missing from the record, and short-term moderate drought developed. On Ailinglapalap, short-term abnormal dryness developed after no rain fell this week, marking the fourth consecutive week with less than 2 inches of rainfall. This dryness is strictly short-term, as November and December were extremely wet. On Jaluit, 0.3 inches of rain were reported this week, and short-term abnormal dryness developed. On Wotje, dry weather was reported this week, marking the fifth consecutive week without any reported rainfall, and short-term abnormal dryness continued. Short-term abnormal dryness developed on Majuro, where 0.14 inches of rain were reported, marking the fourth consecutive week with less than 1 inch of rain. No U.S. Drought Monitor depictions were made for Mili or Utirik as data are missing from both locations.
Short-term moderate drought continued this week on Yap, where 0.23 inches of rain were reported (with 4 days missing). Woleai remained free of drought or abnormal dryness given recent wet conditions; only 0.1 inches of rain were reported this week, though with 4 days missing. On Chuuk, 0.88 inches of rain were reported this week, marking the third consecutive week with less than 2 inches of rain, and short-term abnormal dryness was initiated. On Lukunor, 2.34 inches of rain were reported this week and they remained free of drought or abnormal dryness. On Nukuoro, 0.91 inches of rain were reported this week, and they remained free of drought or abnormal dryness. On Kapingamarangi, 1.37 inches of rain were reported this week, and they remained free of drought or abnormal dryness. Pohnpei remained free of drought or abnormal dryness this week, where 1.13 inches of rain were reported. Pingelap reported 1.2 inches of rain this week, following just 0.05 last week. Given that 5.46 inches of rain fell a couple weeks ago, Pohnpei remained free of drought or abnormal dryness. Kosrae reported 2.96 inches of rain this week, with a couple of missing days, and remained free of drought or abnormal dryness.
Looking Ahead
Over the next five to seven days, it is anticipated that the greatest precipitation will be over the South into the Southeast from east Texas into western Alabama. Much of the country will see little to no precipitation with the most active precipitation areas from California into Wyoming and Montana, but amounts will generally be less than 1 inch for most locations. Temperatures are anticipated to be warmest over the central Plains to the upper Midwest with departures of 5-10 degrees above normal. The coolest temperatures will be in the west with most areas 5-10 degrees below normal.
The 6-10 day outlooks show that the probability of below-normal temperatures is greatest over the Southwest and in New England, while the greatest chances of above normal temperatures are over the High Plains and upper Midwest. Above-normal chances of above-normal precipitation are greatest over the southern United States from New Mexico into the Mid-Atlantic. The best chances of below normal precipitation are over the West and High Plains into the Midwest.
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