The Midwest and Plains: Precipitation was spotty across the Midwest and Plains this drought monitoring period. In Minnesota, drought conditions worsened. The area of D1 in the southwestern part of the state expanded eastward to reflect long-term dryness that is occurring there. The severe drought area located in the north-central part of the state expanded westward into North Dakota’s northeastern corner, as well as eastward to encompass all of Minnesota’s climate division 2. In that same region of Minnesota, D3 conditions expanded northward to the Canadian border. These changes are supported by several time frames out to 60-days of the Regional Climate Centers (RCC) ACIS percent of normal precipitation maps, low rainfall totals and reports of low stream flows.
In Iowa, the area of D2 in the northwestern corner of the state was expanded in all directions. This area missed the rain that fell in that region this drought monitoring period. The ACIS 90-day percent of normal map supports this expansion. In other areas of Iowa, there was minor improvement. The D0 was pulled slightly northward in the northeastern corner to reflect recent rainfall totals of 1-3 inches locally.
In South Dakota, the area of D3 was enlarged in every direction and the D4 slightly expanded south and westward. Along the border of South Dakota and Nebraska, the two areas of severe drought were connected. All of these changes are based on short-term percent of normal precipitation indicators from ACIS and local feedback. Also in South Dakota, the Governor has declared a state of emergency to better handle the fires and drought-ravaged counties. Elsewhere in Nebraska, severe drought conditions at the Kansas border were expanded to cover the remainder of south-central Nebraska. Local feedback indicated water allocation restrictions for Harlan County reservoir are being put in place due to the long-term drought conditions.
In the Great Lakes region, several areas received decent amounts of precipitation while others received little to none during this drought monitoring period. In Illinois, improvements were made to the D0 area in the central region of the state. Both areas of abnormally dry conditions were retracted westward based on local feedback of little to no impacts being reported at this time, and this area also received 1-2 inches of rainfall. In Wisconsin, the southern area of the abnormally dry conditions was retracted northward.
This change is based on local feedback, recent precipitation received this period, the Midwest Regional Climate Center’s (MRCC) soil moisture products and the ACIS 7-, 14-, 30-day and 6-month percent of normal precipitation.
The South: In Georgia, severe drought conditions were expanded eastward to cover the majority of climate division 5 and about half of climate division 7. In the northern part of the state, D1 was expanded from the far northwestern corner of Georgia into the southeastern corner of Tennessee. Also in Tennessee, abnormally dry conditions expanded to cover all of the Cumberland Plateau. These changes are based on the ACIS 7-, 14- and 60-day percent of normal precipitation maps. Degradations are also based on reports of low stream flows, local input, CPC’s soil moisture anomaly and percentile indicators, and minimal amounts of rainfall this drought monitoring period. Further south, in Alabama and Mississippi drought conditions also worsened this drought monitoring period. While some central locations received 1-3 inches of rain, the coverage was too spotty to warrant improvement in these states. The D1 was expanded slightly northward to cover the remainder of abnormally dry conditions in both states. These changes are based on recent low rainfall amounts along both borders and local reports of cotton, soybean and corn crops suffering. The National Weather Service in Huntsville, Alabama, is reporting approximately 12 inches below normal for year-to-date totals at the end of this drought monitoring period. In Louisiana, no changes were made this week, but conditions have started improving in the Delta. Reports of lawns greening up and improvements in agriculture warranted a new impacts line of H only conditions. Year-to-date rainfall deficits are still large for New Orleans with 19.90 inches below normal and Baton Rouge 19.92 inches below normal. However, this area is one to watch over the next several weeks as tropical moisture continues to have an effect.
Arkansas had minor changes this week. The two separate areas of D2 in the southern portion of the state were connected along the Louisiana border. This change was based primarily on the ACIS 30-day percent of normal precipitation map, no rainfall this period, local feedback, and CPC’s soil moisture products.
In the Southern Plains, several changes were made to reflect continued worsening drought conditions. In Oklahoma, extreme drought conditions were expanded to cover the majority of the state with the exception of the panhandle and the eastern region. In the eastern part of the state D1 and D2 areas were expanded northward, connecting the D2 with that in Missouri. These changes are based on low amounts of rainfall, reports of major economic impacts, poor crop conditions and, due to the high temperatures, high evapotranspiration rates. Local reports indicate towns in central Oklahoma, including Norman, lost their water supply recently when a 72-inch main water line broke due to shifting as the soil dried. Several towns across the state had to enforce immediate watering bans.
In Texas there were quite a few changes in several different areas of the state ranging from improvements to degradations. Improvements were made along the Gulf Coast where D1 and D0 areas were retracted northwestward based on local feedback, the ACIS 90-day, 3- and 6-month percent of normal precipitation maps, CPC’s soil moisture products, recent heavy rainfall and high month-to-date precipitation totals. Elsewhere in Texas, the two separate areas of extreme drought located in the north-central region of the state were connected and expanded with an introduction of D4 into the Dallas area. This degradation was based on the 60-day percent of normal precipitation map, lack of rainfall, local feedback and reports of low lake levels in the region. Just south of this area, D2 was expanded westward in the central portion of the state and D3 was expanded northward near Midland. These expansions are based on several time frames of the ACIS percent of normal precipitation maps out to 6-months, local feedback and very low amounts of precipitation this drought monitoring period.
The Rockies and the West: The only changes made in this area during this drought monitoring period were to Montana and Wyoming. In Montana, the abnormally dry conditions were expanded to cover the remainder of the state. A new area of D1 was introduced around the Missoula area and the existing D1 was expanded along the Canadian border. Also in Montana, D2 in the southeastern part of the state was expanded northward. These changes are based on present fire conditions, lack of precipitation for the month, recent hot temperatures, local feedback, worsening stream flows and CPC’s soil moisture products. In Wyoming, abnormally dry and moderate conditions expanded further into the southwestern portions of the state. Also in this area, D3 expanded northward and D2 expanded and merged over north-central Wyoming, leaving a donut hole of D1 in the northeast. In southeastern Wyoming, there were improvements. D2 was pulled back slightly around Cheyenne where good rains fell this period, lessening the longer-term deficits. These changes are based on the ACIS percent of normal precipitation maps out to 6 months.
Areas to watch closely in this region over the next several weeks include Idaho, Washington and Oregon. Currently Idaho is still several inches above normal for the water year, but has not received recent rainfall and the temperatures have been much above normal. Also, Washington and Oregon coastlines are beginning to show signs of dryness, but this is the dry time of year there and reservoirs are in good shape.
Alaska and Hawaii: No changes were made to the abnormally dry areas this drought monitoring period in either state.
Looking Ahead: Over the next 5 days (July 26 - 30), an upper level ridge is expected to be located over the central US. Normal and above normal temperatures are forecast for much of the Lower 48 States. Conditions are favorable for below normal temperatures in the Pacific Northwest, southern New Mexico, southwest Texas, and northern Maine. Tropical moisture is expected to bring additional rainfall to areas along the Texas coast and Louisiana border. Monsoonal precipitation events are likely in the 4-Corners region. Increased precipitation opportunities are likely in the Southeast. Dry conditions are likely to prevail throughout the Plains and the Northeast.
Over the ensuing 5 days (July 31 - August 4), conditions are favorable for normal to above normal temperatures for the majority of the Lower 48 States. Areas with wetter than normal conditions forecast include the Southeast, the 4-Corners region, and the extreme Northwest. The outlook for Hawaii includes isolated precipitation events. Tropical Storm Daniel is not expected to impact the Islands at this time. Alaska is forecast to have normal to below normal temperatures throughout the state, with wetter than normal conditions likely for the extreme northwest and southeastern coastal areas.
Author: Candace Tankersley and Liz Love-Brotak, National Climatic Data Center, NOAA/NESDIS/NCDC
EDIT/END
http://drought.unl.edu/dm/monitor.html