During the week, a highly variable weather pattern brought wide temperature swings to much of the contiguous United States. An unusually cold airmass that had settled over the Plains at the start of the week pushed eastward, bringing a rapid and stormy end to the early season heat wave across the Eastern Seaboard. In contrast, the West baked under much above normal temperatures. By mid-week, much above-normal temperatures had returned to the Plains, with daily maximum temperatures climbing into the upper 90s in some locations. As temperatures began to rebound across the East, cooler air overspread the Pacific states by the end of the week.
The strong temperature gradients that set up across the Nation, coupled with ample Gulf moisture streaming northward resulted in widespread heavy and persistent precipitation, with many locations exceeding two inches from eastern Texas and Oklahoma northeastward to the mid-Atlantic states, and isolated instances of 6 or more inches in some spots. Widespread rainfall, albeit with lighter accumulations, fell across the north-central Plains as daily temperatures warmed, but mostly dry weather prevailed across the upper Mississippi Valley and western Corn Belt. West of the Rockies, mostly dry weather prevailed for most of the week, but showers associated with a strong cold front overspread the Northwest at the very end of the period.
Hot temperatures at the beginning of the week yielded to a cool, unsettled pattern across the Northeast region. Widespread rainfall overspread the region, convectively driven initially along a cold front, followed by steady stratiform precipitation. Soaking rains fell across the southern portion of the region, with 2 to 4 inches of precipitation common across West Virginia, Maryland, and southern Pennsylvania, and amounts decreasing towards northern New England. The steady rainfall and cooler temperatures were ideal for recharge, boosting soil moisture and streamflows across the mid-Atlantic states. Therefore, widespread drought reductions were introduced to West Virginia, Maryland, and southern Pennsylvania, especially where accumulations were greater than 3 inches. Despite the short term benefits, longer term drought impacts to groundwater and reservoirs remain. This is also evident in the drought indicators, with short term SPI values returning to near normal, but longer term SPI values remaining negative. Based on these evolving impacts, the drought classification across Pennsylvania and Maryland was changed from short and long term drought to long term drought only. Further north, improving groundwater conditions yielded modest reductions of abnormal dryness across parts of Maine and Vermont. In contrast, drier conditions over southeastern New England resulted in small areas of degradation in Rhode Island and eastern Massachusetts.
Southeast
A slow-moving frontal boundary and ample moisture advecting northward from the Gulf of America resulted in copious rainfall across the Southeast. Weekly accumulations of 2 to 6 inches fell across all of Mississippi, western and northern Alabama, the Florida Panhandle, much of Georgia, and portions of the southern Appalachians and Piedmont. Accumulations closer to an inch fell across east-central Alabama, central Georgia, the Atlantic coastal plain, and portions of North Carolina and Virginia. Rainfall during the week was above-average and successfully overcame the high evapotranspirative demand that is typically in place this time of year. Therefore, widespread drought reductions were introduced across the region, with the highest coverage of improvements across Alabama and Mississippi. Heavy rainfall over the Florida Panhandle and southern Georgia began to chip away at the western portion of exceptional (D4) drought, though improvements were more meager across the rest of Georgia and the Florida Panhandle, where spottier accumulations came up against highly entrenched drought conditions. Beneficial rainfall yielded reductions across the piedmont region of the Carolinas and the Blue Ridge, while lighter rainfall led to status quo across the coastal plain and portions of northern North Carolina and central Virginia.
South
Widespread heavy rainfall overspread the Southern Region, with amounts increasing from west to east. Accumulations of 2 to locally more than 5 inches fell across most of Tennessee, engendering widespread drought reduction. Rainfall was locally heavy but a bit spottier across Louisiana and Arkansas, which also saw widespread drought reduction but with less coverage. Across Texas, heavy rainfall across the eastern half of the state yielded drought improvements and also localized flooding. Across North Texas, localized convection brought relief to some areas, but hot conditions resulted in degradation where precipitation did not occur.
Midwest
Another mostly dry week across the northern Mississippi Valley and western Corn Belt exacerbated short term dryness, with reports of browning grass and increased irrigation across the region, though longer term drought indicators remain favorable. Due to these short term impacts, abnormal dryness (D0) was introduced to northwestern Indiana, northern Illinois, southern Wisconsin, northeastern Iowa, and along the Mississippi headwaters region. Light rainfall overspread the Great Lakes region, which was sufficient to maintain stability. In contrast, heavy rainfall (2 to 6 inches) fell across the Ohio Valley, from southern Indiana across much of Ohio and all of Kentucky. In these regions, abnormal dryness quickly gave way to localized flooding and standing water, resulting in substantial reductions in the depiction of drought and abnormal dryness. In fact, 2-class changes occurred across parts of northern Kentucky and southern Ohio, where accumulations were the highest.
High Plains
As below-normal temperatures transitioned back to a hot pattern across the High Plains, widespread precipitation moved through the region. Areas of convection brought up to 2 inches of rain to portions of eastern Nebraska and eastern Colorado, while amounts were generally an inch or less elsewhere. This precipitation was sufficient to bring some drought reduction across northern and northeastern Colorado, but drier conditions across southeastern Colorado and Kansas, coupled with hot temperatures, resulted in degradation. A sharp cutoff in precipitation was also noted across the far western Dakotas, where small areas of degradation were noted along the borders with Wyoming and Montana.
Mostly dry weather and above-normal temperatures dominated the Western Region during the week sparking some small-scale degradation across Montana, Idaho, and New Mexico, where the effects of the meager winter snow cover are beginning to be felt in falling streamflow values. Status quo was maintained west of the Rockies for the most part, as reservoir conditions remain good across California during a climatologically dry time of year. At the end of the week, a strong cold front brought abnormal moisture to the Northwest and northern Rockies. While not sufficient to substantively alter the drought depiction, a modest reduction in abnormal dryness was noted in far northwestern Washington.
Persistently suppressed convection over the last few weeks across the Caribbean region, which is partly tied to an atmospheric response to warming ocean temperatures across the equatorial Pacific as well as an Indian Ocean and Pacific MJO event, resulted in the introduction of D0 across portions of southern Puerto Rico during previous USDM releases. During this week, showers and thunderstorms overspread Puerto Rico and the US Virgin Islands, While accumulations were fairly low across the D0 areas, the precipitation was sufficient to stave off further degradation at this time.
Dry conditions persisted across the U.S. Virgin Islands this week, with all locations remaining in short-term abnormal dryness. On St. John, Rafe Boulon/Windswept Beach reported 0.47 inches of rain, bringing the May month-to-date total to 1.54 inches as of May 25, which remains below the monthly normal. Groundwater levels at the Susannaberg DPW 3 well were 14.39 feet below the land surface on May 26; analysis shows that water levels have mostly declined since October 19, 2025 (when the level was 7.56 feet), despite a slight, temporary recovery in mid-April. Over the past year, this groundwater level has dropped approximately 4.33 feet from the 8.96 feet reported on May 26, 2025. This localized dryness is backed up by the 1-month SPI, which indicates dry conditions on the island, though longer 3-, 6-, 9-, and 12-month SPI timescales still show a slight residual wet signal.
Meanwhile, a total of 0.38 inches of rain was reported on St. Croix at Henry Rohlsen Airport this week, leaving the month-to-date total at 1.06 inches as of May 25. The depth to water at the Adventure 28 Well was 21.76 feet below the land surface on May 26, reflecting a steady and severe decrease over the past year. This is a drop of 7.83 feet compared to this time last year, when the groundwater level sat at 13.93 feet on May 26, 2025. Reflecting this prolonged deficit, the 1-, 3-, 6-, and 12-month SPI values all confirm prevailing dry conditions on St. Croix, with only the 9-month SPI maintaining a wet signal.
On St. Thomas, Cyril E. King Airport reported a weekly rainfall total of 0.23 inches, bringing its May month-to-date total to 2.52 inches as of May 25. The depth to water at the Grade School 3 well was measured at 9.16 feet below the land surface on May 26. Groundwater levels here have been on a steady decline since April 20, 2026 (when the level was 4.13 feet), dropping 5.03 feet in just over a month; furthermore, this level is down 7.12 feet from the 365-day maximum of 2.04 feet recorded on October 19, 2025. SPI values confirm these emerging deficits, showing dry conditions at the 1-, 3-, and 6-month timescales, while longer-term SPI timescales for the island were unavailable.
Pacific
Cool, wet weather continued across much of Alaska during the week, which was favorable for moisture recharge. Accordingly, the remaining areas of abnormal dryness (D0) that were over the Kenai Peninsula and the Katmai National Park were removed in this week's USDM.
Across Hawaii, above-normal precipitation continued, though the heaviest amounts fell across the windward slopes of Maui and the Big Island instead of where abnormal dryness (D0) continues. Drought indicators continue to reflect improving conditions; however, the vegetative health index (VHI) remains quite low across Maui. Therefore, status quo was maintained this week.
Wet conditions dominated American Samoa this week, with Pago Pago reporting a weekly rainfall total of 6.33 inches, pushing the May month-to-date total past 20 inches as of May 26. Additionally, Toa Ridge and Siufaga Ridge reported substantial weekly rainfall totals of 7.23 and 6.33 inches, respectively. Consequently, Pago Pago remains completely free of drought and abnormal dryness.
Palau remained free of drought or abnormal dryness as wet conditions persisted. The Koror COOP site reported a weekly rainfall total of 5.18 inches, bringing its month-to-date total to 16.63 inches as of May 26.
Conditions were wetter than normal over most of the Mariana Islands this week. Rota and Guam reported weekly rainfall totals of 2.04 and 1.44 inches, respectively—well above the islands’ one-inch minimum weekly threshold to meet water needs. Saipan received 0.85 inches, and though this fell slightly below the weekly threshold, Saipan and the rest of the Marianas remained free of drought and abnormal dryness.
Conditions were wet across most of the Federated States of Micronesia. Nukuoro, Pohnpei, Kosrae, Lukunoch, Chuuk, Kapingamarangi, and Woleai reported weekly rainfall totals of 9.14, 9.02, 8.28, 4.82, 3.74, 3.36, and 2.91 inches, respectively, keeping all of these locations free of drought and abnormal dryness. Yap reported a weekly rainfall total of 1.59 inches; although this is below the two-inch minimum weekly threshold, Yap remained free of drought and abnormal dryness due to previously wet conditions. Meanwhile, data for Pingelap, Fananu, and Ulithi were insufficient to make an assessment this week.
Wet conditions prevailed across the Republic of the Marshall Islands, where every monitored island surpassed the two-inch minimum weekly threshold necessary to meet water needs. Weekly rainfall totals for Jaluit (4.23 inches), Utirik (3.31 inches), Wotje (3.07 inches), Majuro (2.97 inches), Mili (2.21 inches), Kwajalein (2.07 inches), and Ailinglapalap (2.01 inches) successfully kept all locations free of drought and abnormal dryness.
Looking Ahead
During the upcoming week, a late season storm system across the West is forecast to bring abnormal moisture to California, Oregon, and Washington, with precipitation spreading eastward to the northern Rockies by mid-week. The heaviest accumulations are forecast across the southern Cascades. Periods of convection are favored across the Plains states throughout the week, with the WPC 7-day quantitative precipitation outlook showing a potential for 1 inch or locally more across portions of Nebraska and Kansas, where Gulf moisture advection is most pronounced. Across the eastern third of the CONUS, unsettled weather is favored to continue across the Southeast, with the focus of heaviest precipitation shifting towards Florida and the south Atlantic coastal plain. A slow moving cold front is forecast to push east during the period, maintaining showery weather across the Deep South while cooler and drier conditions overspread the Corn Belt and Northeast.
During Week-2, the trough over the East is favored to rapidly de-amplify, with temperatures quickly moderating. Above-normal temperatures are favored across the West and northern tier of the CONUS on the latest CPC 8-14 day outlook, with mostly near-normal temperatures the most likely outcome across the South and Southeast regions. Unsettled weather and continued precipitation may play a role in keeping hot weather at bay across the southern tier. The CPC 8-14 day precipitation outlook favors above-normal precipitation across the Four Corners states eastward along the southern tier to the Atlantic coastline as far north as Virginia. Near normal precipitation is favored elsewhere, except for a small wet signal over the Pacific Northwest. Above-normal precipitation is favored for eastern Alaska, while above-normal temperatures and above-normal precipitation are both favored for Hawaii.
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