California and National Drought Summary for January 27, 2015
Summary
Temperatures during the last week were well above normal over the majority of the United States, with departures of up to 20 degrees Fahrenheit above normal over the High Plains and northern Rocky Mountains. A few areas did experience temperatures below normal, mainly confined to west Texas and eastern New Mexico as well as southern New England, where departures were 5-10 degrees Fahrenheit below normal. At the end of the current Drought Monitor period, a strong winter storm impacted much of the northeastern United States with strong winds and snow. Most of the country was fairly dry over the last week with the southern plains, Gulf Coast, and southeast receiving the most precipitation. The western United States remained dry, and some areas are on track to having one of the driest Januarys on record.Gulf Coast
Significant rain fell along the Gulf Coast, where 2-3 inch readings were common from Louisiana to Alabama. A full category improvement to the drought status was made this week in response to this precipitation and the positive impact on conditions.Hawaii, Alaska and Puerto Rico
There were no changes made in Alaska, Hawaii, or Puerto Rico this week.Mid Atlantic and Southeast
South Florida remains dry, but most of the rest of the region did receive some precipitation over the last week. With the ongoing dryness in south Florida, the abnormally dry conditions were expanded this week. The driest areas were in northern Georgia and Alabama, extending into the Tennessee Valley. Most of this area recorded temperatures that were normal to slightly above normal for the week. Changes for the U.S Drought Monitor this week consisted of a slight expansion of abnormally dry conditions in southern Virginia and northern North Carolina due to the short-term conditions. In western Kentucky, D0 and D1 conditions were expanded to the south and east respectively while D0 was expanded in western Georgia. On the coast of South Carolina, the small areas of D0 were removed this week along with a small area of D0 in eastern Maryland and the Delmarva Peninsula.Midwest
Another dry week with above-normal temperatures was common over the Midwest this week. Temperatures were 3-12 degrees Fahrenheit above normal, with the greatest departures over the upper Midwest. Precipitation of less than 0.50 inches was common throughout the region. Even with the winter being a dry time of year in the Midwest, the last 3 months have been well below normal for precipitation and snowfall too. The short-term indicators are picking up this dryness. Coordinating those indicators, large areas of abnormally dry conditions were introduced this week from northwest Missouri into Iowa and east into Illinois and southern Wisconsin. In Minnesota, moderate drought was introduced into the northern portions of the state as well as along the border with North Dakota. Much of the rest of Minnesota had abnormally dry conditions introduced in response to the winter dryness.South
Most of Texas and southern Oklahoma recorded precipitation this week, but most other areas were dry. Temperatures were 2-6 degrees Fahrenheit above normal over most areas except west Texas, which was 2-4 degrees Fahrenheit below normal. Improvements to the drought status were made in southern and eastern portions of Texas in response to this week’s precipitation. Degradation took place over northeast Oklahoma in response to record low lake levels, introducing more severe drought to the region. In northeast Arkansas, D0 and D1 conditions were expanded slightly to the south as this area remains dry.The High Plains
As with the Midwest, warm and dry conditions dominated the region. Temperatures were 5-15 degrees Fahrenheit above normal for the week with very few places recording any precipitation. In response to short-term conditions, D1 was expanded north in North Dakota this week.The Northeast
A significant winter storm in the region brought a great deal of precipitation to the coastal regions as well as high winds. Some of the larger metropolitan areas did miss the brunt of the storm, but were impacted none the less. Temperatures were below normal over southern New England, with departures of 4-6 degrees Fahrenheit below normal. Outside of the coastal regions, most of the area recorded below-normal precipitation for the week. Abnormally dry conditions were expanded in portions of western New York this week as the seasonal dryness is impacting the region, especially for winter activities.The West
Continuing the pattern for most of January, the week ended with warm and mainly dry conditions over the western United States. Temperatures were 5-10 degrees Fahrenheit above normal, and only portions of northwest Washington and eastern New Mexico recorded any precipitation of significance. With the ongoing drought, drought intensity did increase in portions of western Nevada as D4 conditions were expanded to the south and D3 conditions were expanded in the north. In eastern Nevada, D1 was introduced along the border with Utah. A large expansion of abnormally dry conditions was introduced from northeast Utah into Wyoming and western Colorado. In Oregon, the D1 conditions were expanded to the west along the Cascades while in Washington, D0 was expanded in the west and northern portions of the state as well as in northeast Washington into the Idaho panhandle. Some areas of central Washington did see enough precipitation to warrant improvement to D2 and D1 conditions.Looking Ahead
Over the next 5-7 days, temperatures are expected to be below normal for most areas east of the continental divide. The greatest departures are projected to be over the upper Midwest and Great Lakes regions while temperatures are expected to stay above normal over the western United States. Models are in fairly strong agreement on a strong storm system developing over the southwest and ejecting onto the plains. This system does pull some Pacific moisture into it, bringing a good chance of precipitation over Arizona, New Mexico and the desert regions of southern California. As this system tracks to the east, much of the southern plains, lower Mississippi River valley, and Mid-Atlantic are expecting to see precipitation of up to 1.50 inches.The 6-10 day outlook continues to show that the western third of the United States has the highest probabilities of above-normal temperatures. After being above normal during the last few weeks, the eastern half of the country looks to get back into a more seasonal pattern, with the best chances of below-normal temperatures over New England. The drought in the west will not see much relief through the first week of February as the area remains likely to have below-normal precipitation. There are also above-normal chances of below-normal precipitation through much of the plains, Midwest, Gulf Coast and Ohio River valley, while portions of the central and northern Rocky Mountains and the southeast look to have the best chances of receiving above-normal precipitation.
Author(s):
Brian Fuchs, National Drought Mitigation Center
Dryness Categories
D0 ... Abnormally Dry ... used for areas showing dryness but not yet in drought, or for areas recovering from drought.Drought Intensity Categories
D1 ... Moderate DroughtD2 ... Severe Drought
D3 ... Extreme Drought
D4 ... Exceptional Drought
Drought or Dryness Types
S ... Short-Term, typically <6 months (e.g. agricultural, grasslands)L ... Long-Term, typically >6 months (e.g. hydrology, ecology)
