Widespread Drought Degradation For South, Southeast; Mixed Results Elsewhere
A soggy, wintry weather pattern was seen in the western U.S. and Northern Tier last week, including a powerful nor’easter. Despite the active weather, there were mixed results to the drought depiction. Meanwhile, generally dry, unseasonably mild and occasionally windy weather prevailed across the south-central and southeastern U.S.
Northeast
A series of fast-moving weather systems moved across the Northeast for the first half of the drought monitoring period, then a powerful nor’easter impacted the region for the second half. With the quicker moving systems, snow or mixed wintry precipitation was generally limited to higher elevations and farther inland, while the coast saw mainly rain. Southern portions of the Northeast saw significant wet, heavy snow with the nor’easter, with northern areas lower snowfall amounts that was more of a “dry” consistency. The nor’easter deposited more than a foot of snow in major East Coast cities from Philadelphia to Boston, with a single storm record of 37.9 inches measured in Providence, R.I.
The combined events led to improvements of up to one drought category in the Mid-Atlantic, as liquid precipitation totals topped 2 inches in many locations. These improvements were seen in north-central and south-central Pennsylvania, southeastern New Jersey, much of Maryland and eastern West Virginia. Most notably, severe drought (D2) was removed from eastern West Virginia, and it was almost completely removed from Maryland, with only small areas of severe drought only remaining in western and north-central Maryland. Moderate drought (D1) contracted elsewhere.
Areas north of New York City saw a “drier,” more powdery snow and had water equivalency values largely remaining less than an inch, despite hefty accumulations. Additionally, heavy precipitation failed to advance very inland, leaving “status quo” conditions for much of the Northeast.
Southeast
The Southeast also saw several weather disturbances dart across the region throughout the week. Virginia was also impacted by the nor’easter towards the end of the drought monitoring period. These disturbances brought generally spotty light rainfall, though there were some streaks of moderate to heavy rain. Virginia initially received beneficial rainfall from the nor’easter, which switched over to a wet, heavy snow as colder air filtered in.
All this resulted in widespread drought improvement in Virginia this week. Severe drought (D2) contracted significantly, but there is still an area of severe drought in south-central portions. Moderate drought (D1) also decreased in coverage across southeastern parts. Some smaller areas of improvement also occurred in southern South Carolina and central/southeastern Georgia. Extreme drought (D3) decreased slightly in southeastern Georgia, with improvements made to severe drought (D2) elsewhere.
For the rest of the Southeast, the rain was not significant enough to help improve drought conditions. In fact, the rest of the region saw worsening drought conditions. Several Southeastern wildfires have flared in recent days, and by February 24, the National Fire had charred 25,000 acres in Collier County, Fla., in Big Cypress National Preserve. Severe and extreme drought (D2-D3) worsened in western South Carolina, northern Georgia and east-central Florida (near the Space Coast), while severe drought expanded in southern North Carolina. Abnormal dryness and moderate drought (D0-D1) also worsened in northern and western Alabama
South
A fast-moving disturbance brought isolated light showers to eastern portions of the Southern region around the middle of the drought monitoring period. Otherwise, dry and unseasonably warm weather occurred for the rest of the period.
In fact, the southern High Plains endured a historic day of wind and wildfires on February 17, when the Ranger Road Fire was ignited in Beaver County, Okla. The Ranger Road Fire soon scorched more than 280,000 acres of grass and brush, expanding into northwestern Harper County, Okla., and parts of three counties in southwestern Kansas. Meanwhile, the Lavender Fire burned more than 18,000 acres northeast of Vega, Texas, and reportedly destroyed at least 18 structures. On February 17, the day of ignition, peak gusts included 73 mph in Lubbock, Texas, and 67 mph in Guymon, Okla.
Due to deteriorating conditions and diminishing topsoil moisture reserves, moderate drought (D1) was broadly introduced across northern and western Oklahoma and the northern panhandle of Texas. Farther east, gradually worsening drought conditions were also observed from the western Gulf Coast region to the Mississippi Delta, with several new areas of extreme drought (D3) being introduced and others being expanded. Coverage of exceptional drought (D4) increased slightly in southern Texas. Currently, over 80-percent of Texas is experiencing some form of drought, and Oklahoma and Arkansas are both over 90-percent drought coverage.
Midwest
Northern and eastern portions of the Midwest saw a parade of low-pressure systems move through this week, with snow being the predominant precipitation type. Meanwhile, southern and western areas generally missed out on these storms and stayed largely dry. Improving drought conditions in the vicinity of the Great Lakes contrasted with ongoing drought degradation farther south and west.
Drought improvements were noted in Minnesota’s Arrowhead region, northern Wisconsin, northern portions of Michigan’s Lower Peninsula and a small area of central Missouri. A small area of severe drought (D2) was removed from northeastern Wisconsin, while moderate and severe drought (D1-D2) contracted across northeastern Minnesota and the rest of northern Wisconsin.
Degradations were noted in southern Minnesota, most of Iowa, northern and eastern Missouri, northern and southern Illinois, southern Indiana and western Kentucky. Most areas saw an expansion of abnormal dryness and moderate drought (D0-D1). Though, severe drought did expand from west-central Illinois into northeastern Missouri. Overall, patchy extreme drought (D3) persisted from southern Missouri into northwestern Ohio.
Some locations in the lower Ohio Valley and neighboring areas may soon complete their driest meteorological winter (December-February period) on record. From December 1 – February 24, precipitation in Paducah, Ky., totaled 3.21 inches, just 28 percent of normal. Even lower season-to-date totals were observed in Springfield, Mo., (3.13 inches); Carbondale, Ill., (2.49 inches); Poplar Bluff, Mo., (2.44 inches); Joplin, Mo., (2.16 inches); Gape Girardeau, Mo., (2.09 inches); and West Plains, Mo., (1.75 inches).
High Plains
The first half of the drought monitoring period saw a fairly active weather pattern, with storms generally moving from Wyoming and Colorado into the Dakotas and western/northern Nebraska. Snow was the predominant precipitation type, though the Dakotas occasionally saw a wintry mix. A drier weather pattern then occurred for these areas for the second half of the period. Southern/eastern Nebraska and most of Kansas stayed dry throughout the period.
Despite the active pattern to start the monitoring period, gradual drought deterioration was noted in several areas, except North Dakota, which remains free of drought. Severe drought (D2) increased in coverage across southwestern South Dakota, western/northeastern Nebraska, far western Wyoming and northeastern Colorado. The rest of southern South Dakota, northeastern and eastern Nebraska, southern Kansas and northeastern Colorado saw a worsening of abnormally dry and moderate drought (D0-D1) conditions.
Conversely, beneficial snow in southwestern Colorado did lead to some localized improvements. Here, moderate and severe drought (D1-D2) improved slightly.
Parts of Kansas and Colorado contended with high winds, grassfires, and blowing dust, especially on February 17. On that date, wind gusts in Colorado were clocked to 79 mph in Colorado Springs, 72 mph in Burlington, and 71 mph in Pueblo. South of Pueblo, on I-25, chain reaction collisions due to low visibility in blowing dust resulted in five fatalities and involved approximately three dozen vehicles.
West
There were few overall changes in the West this week, as most of the heavy precipitation fell in areas that are currently experiencing no drought, such as northern and central California. Farther inland, brief bursts of precipitation in drought-affected areas prevented worsening conditions but provided little overall relief.
A small area of improvement occurred in far southwestern Oregon and far northwestern California, where abnormally dry and moderate drought (D0-D1) contracted slightly. At the same time, western and central Montana did see drought worsen this week. Moderate drought (D1) expanded in western Montana, while severe drought (D2) increased in coverage across central portions of the state.
In Utah’s Wasatch Range, Alta received 31.2 inches of snow in a 24-hour period on February 17-18 but will likely end the month with below average snowfall. Below average snow-water equivalency remains a concern in much of the West, even in drought-free areas such as the Sierra Nevada. According to the California Department of Water Resources, the Sierra Nevada snowpack contained an average snow-water equivalency of 16 inches, about 6 inches from earlier in the month, but less than three-quarters of normal for late February. In much of Arizona, New Mexico, and Oregon, snow-water equivalency values were less than 50 percent of normal.
Looking Ahead
Fast-moving, loosely organized weather systems will move across the U.S. over the next week, bringing varied conditions. The Southeast is expected to receive the heaviest rainfall, locally 1 to 2 inches or more, primarily through Friday, Beneficial showers will also continue across Florida’s Peninsula.
Meanwhile, dry weather will dominate the southwestern quadrant of the country, from southern California to the central and southern High Plains. This dryness will be paired with record-setting warmth. This will likely lead to degradations to the drought depiction.
Farther north, a new surge of Pacific moisture is forecast to reach southern Oregon and northern California by the middle of the monitoring period, then quickly push eastward. This system is likely to produce wintry precipitation towards the end of the period from the central Plains to the Mid-Atlantic, including the Ohio Valley and surrounding areas.
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Source: U.S. Drought Monitor