California and National Drought Summary for July 14, 2015
Summary
This U.S. Drought Monitor week saw some minor improvements in the Northeast while continued generally hot and dry conditions led to minor degradations in the southern portions of the Mid-Atlantic states and Southeast. Further west, recent rainfall activity continued to improve conditions in western Colorado and Texas while southeastern Idaho saw deterioration in conditions as a result of above-average temperatures and precipitation deficits during the past 60 days. In recent weeks, anomalously wet conditions in northeastern California led to minor improvements in areas of exceptional drought. Overall, temperatures were above normal across northern portions of the Pacific Northwest, Northern Plains, and the Southeast during the past week. In contrast, unseasonably cool temperatures were observed across the remainder of the West, Central and Southern Plains, and Midwest. Precipitation accumulations this week were greatest (in excess of five inches) in southern portions of the Midwest where a series of upper- level disturbances along a stationary front led to heavy shower and thunderstorm activity that impacted the region resulting in significant flash flooding in Kentucky. Elsewhere, pockets of heavy rainfall were observed in portions of Texas and eastern Oklahoma.Hawaii, Alaska, and Puerto Rico
On this week’s map, conditions deteriorated slightly on the Big Island, Kauai, Maui, and Oahu in response to short-term precipitation deficits, hot temperatures, and deteriorating pasture conditions being reported. In Alaska, long- and short-term precipitation deficits and above-average temperatures led to the expansion of Moderate Drought (D1) across the interior region. In Puerto Rico, continued dry conditions are impacting agriculture and streamflows along the South Coast near Santa Isabel and Salinas. In response, an area of Severe Drought (D2) was expanded to cover these regions.Mid-Atlantic
During the past week, the Mid-Atlantic was generally dry except for West Virginia which received moderate-to-heavy precipitation accumulations (two-to-five inches). In Virginia, precipitation accumulations were generally less than two inches with the exception of some isolated pockets were rainfall accumulations ranged from two-to-three inches. In North Carolina, precipitation was generally limited to less than one inch with the exception of extreme northeastern North Carolina which received two-to-four inches. On the map, precipitation deficits during the past 30–60 days led to minor expansion of areas of Abnormally Dry (D0) in northeastern and far western portions of the state. During the past week, average temperatures were near-to-slightly-below normal in eastern Virginia and parts of West Virginia while much of North Carolina was two-to-four degrees above normal. According to the NOAA NCEI statewide precipitation rankings, both Virginia and West Virginia experienced near-record precipitation totals for the month of June as well as near-record heat across most of the region.Midwest
During the past week, cool and unsettled weather impacted much of the region with severe flash flooding occurring in parts of Kentucky and heavy rainfall accumulations (three-to-six inches) observed in central Illinois, Indiana, Kentucky, and southern Ohio. On the map, an area of Abnormally Dry (D0) was introduced in northwestern Iowa in response to short-term precipitation deficits, low streamflows, and low soil moisture. Overall, temperatures were below normal across most of the region during the past week. According to the NOAA NCEI statewide precipitation rankings (based on the last 121 years) for the period of April through June, portions of the Midwest experienced near record wettest with the following rankings: Illinois (118/121), Indiana (117/121), and Ohio (116/121).The Northeast
The Northeast continued to see improvements on the map this week in areas of Abnormally Dry (D0) and Moderate Drought (D1) in New York State, as recent rainfall activity improved soil moisture and streamflow conditions. Areas of Abnormally Dry (D0) were reduced in Connecticut and Massachusetts in response to one-to-two inches of rain falling during the past week. According to the National Centers for Environmental Information (NCEI), the Northeast region experienced one of its wettest Junes for the period of record from 1895 to 2015.The Plains
Across the central and southern Plains states, temperatures were well below normal for the period while the northern Plains were above normal. Most of the region was generally dry during the past week with the exception of moderate-to-heavy rainfall accumulations in eastern Oklahoma and some isolated pockets in eastern Kansas. Short-term precipitation deficits and low streamflow led to the expansion of areas of Abnormally Dry (D0) in northwestern Kansas extending just across the border into southwestern Nebraska. In the northern Plains, small areas of Abnormally Dry (D0) were eliminated in southwestern North Dakota and southeastern South Dakota.The South
During the past week, generally dry conditions prevailed across most of the region with the exception of some isolated pockets of heavy shower activity (four-to-eight inches) in west central and some lesser accumulations (two-three inches) in the northwest panhandle of Texas. In these parts, one-category improvements were made in areas of Abnormally Dry (D0) as well as in the sole remaining area of Moderate Drought (D1) in the state. According to the NWS in San Angelo (TX), Abilene already has broken the July rainfall record at 8.26 inches. Statewide, Texas experienced the wettest January through June period on record (1895–2015), according to NOAA NCEI. In Oklahoma, short-term improvements led to removal of the remaining areas of Abnormally Dry (DO) in the Panhandle region. During the past week, temperatures were below normal in the western half of the region while eastern portions hovered near-to-slightly-above normal.The Southeast
During the past week, the Southeast continued in a dry pattern with the exception of some light-to-moderate shower activity (two-to-three inches) in central and north-central Florida. On the map, the hot and dry pattern in south Florida led to minor expansion of areas of Severe Drought (D2) and Extreme Drought (D3) in Broward, Miami-Dade, and Palm Beach counties where groundwater wells are being impacted. Elsewhere in Florida, short-term dryness led to the expansion of an area of Moderate Drought (D1) into Indian River, Martin, and St. Lucie counties. In northern Alabama and central Georgia, short-term precipitation deficits (30 days) and low streamflow activity led to minor expansion of areas of Abnormally Dry (D0) and Moderate Drought (D1). Overall, average temperatures were generally near-to-slightly- above normal across most of the region. According to the National Weather Service (NWS), a daily record high temperature (97° F) was observed during the weekend at both Sarasota-Bradenton and Tampa.The West
During the past week, average temperatures were two-to-ten degrees below normal across most of California, the Intermountain West, and the Southwest. Southern portions of the Pacific Northwest were cooler than normal while northern portions were two-to-eight degrees above normal. The continued overall hot and dry conditions in the Pacific Northwest led to movement of the impact lines on this week’s map to reflect the short-term impacts being reported across the region. Hot and dry conditions during the past 60 days have impacted the region’s agricultural sectors, fisheries, and wildland fire conditions. Warm water temperatures in Oregon have led to fish mortality in both the Deschutes and Willamette rivers. According to the July 6, 2015 USDA NASS Crop Progress and Conditions report, non-irrigated crops in parts of Washington are showing signs of stress. Pastures in central Washington are reported as being short and extremely dry. In southeastern Washington, the winter wheat harvest is expected to be two weeks ahead of schedule. On the map, short-term precipitation deficits and low streamflows led to the expansion of Moderate Drought (D1) in southeastern Idaho. In northeastern California, recent thunderstorm activity led to a one-category improvement in areas of Exceptional Drought (D4) in Modoc County. According to the NRCS in Alturas, the recent rains have improved rangeland conditions as well as area groundwater, ponds, and springs in some locations. In western Colorado, east-central Utah, and southwestern Wyoming, areas of Abnormally Dry (D0) were removed in response to above-average precipitation (both short- and long-term), normal streamflow activity, and improved soil moisture.Looking Ahead
The NWS WPC 7-Day Quantitative Precipitation Forecast (QPF) calls for dry conditions across an area extending from northern California to the Pacific Northwest while portions of the Southwest are forecasted to receive monsoonal moisture with forecast accumulations in the one-to-three inch range – primarily centered over Arizona. Moderate precipitation accumulations (two-to-three inches) are forecasted for eastern portions of the central and northern Plains while the Midwest, Northeast, and parts of the Southeast are expected to receive light-to-moderate accumulations (one-to-three inches). The 6–10 day outlooks call for a high probability of above-normal temperatures along the West Coast while northern portions of the Southwest and Intermountain West are expected to experience below-normal temperatures. Meanwhile, the eastern half of the country has a high probability of above-average temperatures, especially in the Southeast. Out West, there’s a high probability of above-average precipitation forecasted for western portions of the Southwest, southern California, Intermountain West, and eastern portions of the Pacific Northwest. Likewise, the Midwest and Northeast have a high probability of above-average precipitation while Texas and the Southern Plains are forecasted to be dry.Author(s):
David Simeral, Western Regional Climate 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)
Source: The National Drought Mitigation Center
