Rainfall was highly variable across the Nation this past week. Totals exceeding 2 inches were widespread from northern and eastern Indiana through much of Ohio and into West Virginia and western Pennsylvania. Localized areas across central and eastern Indiana, central and southeastern Ohio, and western West Virginia recorded 5 to 7 inches. Interior sections of central and northern Missouri also saw widespread totals topping 2 inches, with a few isolated patches receiving 4 to 5 inches. Other areas with more scattered totals over 2 inches include the Upper Midwest, east-central Great Plains, the southern Great Lakes region, the central and southern Appalachians and adjacent foothills, the Carolinas, central and northern Georgia, and the Florida Peninsula. More moderate amounts, with isolated spots recording 2 to 3 inches, were dotted across the remainder of the Eastern Seaboard, Gulf Coast, Lower Mississippi Valley, and the Desert Southwest where a decent monsoonal circulation remained in place. Meanwhile, little or no precipitation fell on most locations in the seasonably-dry Far West, the Great Basin, the Intermountain West, much of the central and northern Rockies, most of the Plains, the Upper Mississippi Valley, the Great Lakes region, most of the Tennessee and Lower Ohio Valleys, portions of southern New England, the Virginia Tidewater, and adjacent locations. Farther north, a few tenths of an inch of precipitation were observed in central Alaska and the upper half of Southeast Alaska while little or no precipitation fell farther south there. The areas of Hawaii experiencing abnormal dryness (D0) recorded isolated amounts approaching an inch last week, but most of these areas received a few tenths of an inch at best.
Temperatures averaged at least slightly above normal along the West Coast and from the Great Basin and Southwest through the southern Plains and most of the Lower Mississippi Valley. Most areas from the eastern Great Lakes, Ohio Valley, and Mid-Atlantic regions northeastward to the Atlantic Ocean and Canadian Border also experienced a warmer than normal week. Numerous locations from near the Great Basin through Oklahoma and western Texas average 6 to 10 deg. F above normal, as did much of New England. Meanwhile, subnormal temperatures dominated the northern Plains. Other sites across the Lower-48 recorded near-normal temperatures for the week.
In summary, dryness and drought expanded and deteriorated across portions of New Hampshire and Maine, while changes farther south were in the direction of improvement. More than 2 inches of rain, with localized amounts approaching 6 inches, fell through most of West Virginia, portions of western and southern Pennsylvania, northern and central Maryland, and scattered locations from central New York southward through New Jersey and Delaware, as well as the remaining areas across Pennsylvania and Maryland. With warmer than normal weather accompanying subnormal rain across most of New England, abnormal dryness (D0) was expanded across central New Hampshire and much of northern Maine. In southern Maine, moderate drought (D1) expanded northward toward the center of the state while an area of severe drought (D2) was introduced near the state's Atlantic Coast. From lower New England southward through Maryland, many areas of dryness and drought improved, driven the recent increase in precipitation, particularly the heavy amounts reported in many areas the past 2 weeks. Still, some impacts from the dwindling longer-term precipitation deficits persist. Water supplies are still unfavorably low across New Jersey, and 61 percent of the hay crop in West Virginia is in poor or very poor condition, according to the National Agricultural Statistics Service (average at this time of year for the previous 5 years was 19 percent). In addition, some pasturelands remain in poor or very poor condition, including 55% of West Virginia pastures (5-year average 24 percent) and 41 percent of Pennsylvania pastures (5-year average 16 percent). And almost one-third of Maryland corn is also in poor or very poor condition (5-year average 18 percent).
Southeast
Moderate to heavy rainfall fell on much of the South Atlantic States, prompting broad areas of improvement near the I-95 Corridor and across the Piedmont. Improvement was more scattered farther east closer to the coast, and across most of Florida, where moderate to heavy rains weren't as widespread and, in the case of Florida, normal amounts are higher. Deterioration was limited to southern portions of Alabama and Mississippi, where subnormal precipitation and periods of extreme heat have taken their toll over the past several weeks, and in a small portion of southeastern Florida. Over the past 30 days, subnormal precipitation has been limited to portions of southern Virginia, the eastern Carolinas, southern Georgia, much of Florida away from the immediate Gulf Coast, southern sections of Alabama, much of Mississippi, and scattered patches across the rest of the Southeast Region. Most of Mississippi and southern Alabama recorded less than half of normal rainfall since mid-July, along with relatively small patches in other areas with deficient 30-day rainfall amounts. Totals for the past few months have been near or above normal through most of the Region, but longer-term deficits for the past 12 months remain below normal, with many locations still more than a foot below normal for that period. As in the Northeast, some lingering impacts from the longer-term moisture deficits continue to affect the Region. Almost half of North Carolina corn and 39 percent of South Carolina corn is in poor or very poor condition (5-year average 23 percent in both states). Poor or very poor pastureland and hay are also affecting parts of the Region, particularly in Virginia and the Carolinas.
South
Dryness and drought have been expanding and worsening over much of the South Region for the past few weeks. Rapidly deteriorating conditions have been observed across Oklahoma, the Texas Panhandle, and adjacent areas of Arkansas, but almost all states saw declining conditions this past week. Tennessee was an exception, where more widespread heavier rainfall prompted some improvement in central and eastern parts of the state, with persisting or deteriorating conditions limited to northern and western parts of the state. Farther west, deterioration was introduced through most of Oklahoma (especially the eastern half of the state), the Red River Valley, Much of the Texas Panhandle and northeastern Texas, western Arkansas, northern and eastern Louisiana, and scattered patches across the remainder of the Region from the Lower Mississippi Valley westward. Oklahoma has seen very little precipitation over the last 30 days, with most locations reporting less than 25 percent of the normal. Temperatures averaging 3 to 7 deg F above normal mid-summer values significantly exacerbated the drying conditions across much of Oklahoma and northern Texas, including the Panhandle. Temperatures averaged near or up to 3 deg F above normal elsewhere. Much more abundant rainfall prior to the past 30 days is keeping longer-responding impacts from ramping up too quickly, but some crops and streamflows are being deleteriously affected. Almost half of Texas oats and over one-third of Oklahoma soybeans are in poor or very poor condition. Across Oklahoma, 44 percent of pastures and rangelands are in poor or very poor condition, as are 33 percent of those in Arkansas.
Midwest
A variable precipitation pattern was observed last week across the Midwest Region, with deficient precipitation persisting across much of the northern tier of the region, along with scattered locations from central Illinois into southern Indiana. Meanwhile, a swath of heavier amounts brought improvement to significant locations across south-central and northern Missouri, central and eastern Iowa, and the southern tier of the Great Lakes region. Over the past 30 days, most areas in a band from north-central Minnesota through northern Wisconsin recorded less than 25 percent of normal precipitation, with many locations reporting several tenths of an inch at best during that period. Amounts have been a little more generous across the central Lower Peninsula of Michigan, central and southern Illinois, southern Indiana, the southern and northern reaches of Missouri, western Iowa, and central through southwestern Minnesota, but many sites here reported half of normal or less during the past 30 days. In contrast, 30-day totals have been well above normal in part of northern Minnesota, south-central Minnesota through eastern Iowa, part of southern Iowa, central Missouri, near the southwestern coast of Lake Michigan, much of northern and eastern Indiana, most of Ohio, and central Kentucky. This has resulted in the patchwork of varying severities of dryness through the Region, but severe drought (D2) is most common through northern Wisconsin, a large part of central and northern Minnesota, and smaller sections of southwestern Minnesota and interior west-central Iowa.
High Plains
Moderate to heavy rainfall doused portions of eastern Kansas and adjacent Nebraska, leading to some limited relief, but totals were considerably lower elsewhere. Over 0.5 inch with isolated heavy amounts were observed in southern North Dakota, western and southern South Dakota, numerous patches across Nebraska, south-central and west-central Kansas, and the higher elevations of Colorado. Other locations measured a few tenths of an inch, if any. Improvements were restricted to small sections of north-central and southeastern Nebraska while dryness and drought persisted or intensified elsewhere. Areas from south-central through northeastern Colorado, southernmost and northwestern through north-central Kansas, northeastern Nebraska, and the northern half of the Dakotas saw the most widespread deteriorations. Over the past 30 days, most locations outside the highest elevations of Wyoming and Colorado have recorded well below normal precipitation, with less than 25 percent of normal amounts recorded over central and southwestern Kansas and much of North Dakota. There are a few stripes in the Great Plains with near or above-normal 30-day totals, but these conditions cover much smaller areas than those experiencing dryness and drought. Currently, large sections of Colorado and Wyoming are enduring severe to exceptional drought (D2 through D4), with the worst conditions affecting significant portions of Colorado and a few patches in western Nebraska. In the Great Plains, severe (D2) or extreme (D3) drought also extends across much of Nebraska and some adjacent locales, the central and western Dakotas, and a few patches in southeastern South Dakota and southwestern Kansas. The dryness is impacting especially surface moisture stores, including areas of reduced streamflows and degraded crops. Not all crop damage may be the result of dryness and drought, but it is the most significant contributing factor. In Colorado, 64 percent of pastures and rangelands are in poor or very poor condition (5-year average 23 percent), along with 70 percent of those in Nebraska (5-year average 30 percent), and 75 percent in Wyoming (5-year average 38 percent). Several crops in Colorado have a significant proportion in poor or very poor condition, including 46 percent of corn (5-year average 15 percent) and 57 percent of sorghum (5-year average 8 percent). In North Dakota, 53 percent of sorghum and 40 percent of corn are in similar condition (5-year averages of 13 and 15 percent, respectively). Significantly above-normal temperatures have also prevailed during the last 30 days, with temperatures averaging generally 6 to 9 deg F. above normal in the western Dakotas, the adjacent High Plains, central and western Colorado, and western Wyoming, with the largest departures observed in the latter region.
Moderate to locally heavy precipitation (0.5 to 3 inches) fell on much of Arizona and New Mexico primarily due to monsoonal convection. Farther north, a few tenths of an inch with isolated higher amounts of over an inch were recorded across Utah, much of the Great Basin, and some adjacent areas. The rest of the West Region was dry, with only isolated locations reporting as much as 0.2 inch. These conditions brought little change to dryness and drought across the West Region, with changes restricted to several areas of deterioration across the plains of Montana and part of the adjacent northern Rockies, similar to conditions farther east across the northern tier of the central Lower-48. Dryness and drought continue to cover a large proportion of the West Region, sparing only parts of central and western California, coastal areas near the Oregon/Washington border, and west-central Montana. Extreme to exceptional drought (D3-D4) is common across a large swath in interior Oregon, southern Idaho, the adjacent Great Basin, and a large section of Utah. Conditions have been exacerbated by 30-day temperatures averaging 4 to 8 deg F. above normal across Utah, southeastern Idaho, much of southern Montana, and -scattered locations across the Southwest. In Utah, 33 percent of winter wheat is in poor or very poor condition, compared to a 5-year average near zero. In addition, one-half to three-quarters of rangelands in Arizona, New Mexico, and Utah are in poor or very poor condition, which is well above average for this time of year. In addition, multiple years of persistently below-normal precipitation has left some large reservoirs in the West with extremely low water stores. The contents of Lake Mead have dropped to an all-time low since daily reports are available, back to 1937. By August 10, the amount of stored water dropped below 7 million acre-feet (capacity is over 28 million acre-feet).
Some planned water service interruptions have been implemented in parts of the Commonwealth as rainfall totals remained unusually low in most areas. Over 2 inches fell on some areas in western and northeastern Puerto Rico, with 4 to 6 inches soaking parts of Mayaguez on the western coast. Most locations, however, reported less than an inch, with just a few tenths at best falling on south-central areas and along the western half of the southern coastline. Extreme drought (D3) covers the locations reporting the least amount of rain last week, along with some interior northeastern sections, and severe drought (D2) was expanded to cover much of the southern, central, and eastern Commonwealth.
Extreme drought continues to affect the U.S. Virgin Islands. This week, Gov. Albert Bryan Jr. requested a federal disaster declaration for the islands of St. Croix, St. Thomas and St. John, as the drought has impacted agriculture and water supplies. CoCoRaHS stations across St. Croix Island reported anywhere from 0.08” – 0.46” of rain this week. Well water levels at Adventure 28 Well are currently at 25.03 ft., which is 0.32 ft. lower than last week, and 7.65 ft. lower than last year. Across St. John, CoCoRaHS stations reported anywhere from 0.31” – 0.72” of rain this week. The Windswept Beach station reported 0.04” of rain this week. Well water levels at Susannaberg DPW 3 Well are currently at 17.66 ft., which is 0.23 ft. lower than last week and 4.35 ft. lower than last year. The CoCoRaHS station at St. Thomas Island reported 0.15” of rain this week. Well water levels at Grade School 3 Well are currently at 10.58 ft., which is 0.96 ft. lower than last week and 1.16 ft. lower compared to last year. However, Vegetation Health Index (VHI) levels have slightly improved compared to last week.
Pacific
Areas of dryness and drought did not receive significant precipitation last week. Most areas recorded a few tenths of an inch at best, and little or none was measured in the southern half of Southeast Alaska. Well above normal temperatures exacerbated the dryness, and as a result, moderate drought (D1) was introduced in part of central Alaska, inside an expanded area of abnormal dryness (D0). Across Southeast Alaska, dryness and drought were unchanged. Fire danger is increasing, but wildfires have not singed a large part of the state so far. To date, a little over 72,000 acres have been consumed, according to the National Interagency Fire Center (for comparison, wildfires have consumed 6.3 to 6.4 million acres across the other 49 states).
Abnormal dryness (D0) remained intact across the leeward areas, mostly along the southwestern tier of the island chain. Rainfall totals at a few locations in the abnormally dry areas approached an inch for the week, but only a few tenths fell on most locations. Abnormal dryness (D0) was expanded southward to cover the Kona region on the western side of the Big Island, where there have been some reports of coffee crops stressed by the warm and dry weather.
Most of the islands in the Republic of the Marshall Islands have received plentiful rain this week. Ailingalapalap, Kwajalein, and Mili received 3.74”, 3.32” and 5.89” of rain this week, respectively. Several islands did not receive adequate precipitation this week, however. Jaluit, Majuro, and Wotje received 1.03”, 1.32” and 1.4” of rain this week, respectively. Utirik received 0.06”, the least precipitation of the island chain this week.
A dry week was in store of the Federated States of Micronesia. One island received over an inch of precipitation, with Pohnpei receiving 1.05” of rain this week. Chuuk Lagoon, Kapingamarangi, Lukunor, and Nukuoro received only 0.32”, 0.1”, 0.29” and 0.68” of rain this week, respectively. Ulithi, Woleai and Yap received no precipitation this week. Additionally, the island of Kosrae had missing precipitation records this week.
American Samoa will receive a one-category degradation to abnormal dryness this week due to a lack of adequate precipitation for more than three weeks. The Pago Pago Airport received only 0.48” of rain this week. The Siufaga and Toa Ridges received 1.1” and 0.46” of rain this week, respectively. The Republic of Palau has experienced another dry week. The Koror station only reported 0.17” of rain, while the WSO in Palau reported 0.21” of rain. The monsoon season continues to affect the Marianas Islands. Guam, Rota, and Tinian reported 3.51”, 4.51”, and 6.01” of rain this week, respectively. The Saipan International Airport received 5.88” of rain, while the AMME NPS Saipan station received 1.68” of rain.
Looking Ahead
During August 13-17, 2026, moderate to heavy rain (over an inch) is forecast across the central and northern High Plains, the northern Rockies, the Colorado Rockies, scattered locations over the central and western Four Corners region and Great Basin, much of the northern and central Great Plains, the southern and central Great Lakes region, the northern Ohio Valley, and several patches across southern New England, the lower Northeast, southern Georgia, and both the southern and northern reaches of Florida. The highest totals (3 inches or more) are expected across part of east-central Montana, the northeastern quarter of Colorado, and much of a band from central Iowa into western Indiana. In contrast, light precipitation at best is anticipated across northern New England, interior sections of the Middle and Southern Atlantic States, northern portions of the Great Lakes and Minnesota, Lower Mississippi Valley, central and southern Plains, most of the Pacific Coast States, and lower elevations across the Great Basin and the central to southern Rockies. Meanwhile, areas from the south-central Great Plains across the Southeast are expected to record daily highs averaging 5 to 11 deg. F above normal, with the largest anomalies expected from Arkansas through central Tennessee. Farther north and west, daily highs should average 3 to 6 deg. F below normal over much of California and the Great Basin, the Northern Intermountain West, and northern reaches of the Rockies and Plains. Other locations should average closer to normal.
The 6- to 10-day outlook (August 18-23, 2026) at least marginally favors above-normal precipitation across the northern half of the Eastern Seaboard westward through the Great Lakes region, the northern halves of the Mississippi Valley and Plains, and from the Rockies to the West Coast. The best odds for wetter than normal weather (over 50 percent) cover the interior Pacific Northwest. Surplus precipitation is also favored throughout Alaska and Hawaii, with odds topping 40 percent in south-central Alaska and through the Hawaiian Island Chain. Subnormal totals are somewhat favored from the southern Great Plains through the Gulf Coast region and Florida. Meanwhile, warmer than typical mid-August conditions should dominate all 50 states, excepting only southwestern Alaska and the Aleutians, most of the central West Coast States and adjacent Great Basin, and the northern tier of the Lower-48 from the northern Plains through most of New England. The likelihood of unusual warmth top 70 percent from the southern Great Plains eastward through the Southeast and South Atlantic Coast, as well as southeastern Maui and the Big Island of Hawaii, and part of east-central Alaska. Chances exceed 80 percent from the central Lower Mississippi Valley into the interior central Gulf Coast States. Odds marginally favoring subnormal temperatures are restricted to the Aleutians and northern Maine.
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