Heavy to excessive rainfall impacted significant parts of the Contiguous States this past week. Amounts of 4 to locally over 8 inches of rain were common across south-central and southeastern Georgia, northeastern Florida, the Florida Panhandle, portions of the immediate Gulf Coast, and a swath from central Texas through the middle Red River (South) Valley. This brought an abrupt end to a protracted spell of hot and dry weather across the southern Great Plains that dated back through most of the summer. Dallas, TX recorded 4 inches of rain from September 30 through the first week of October, including a daily total of 3.47 inches on October 1. Prior to that, Dallas recorded only 0.01 inch of rainfall July 16 through September 29 (76 days), and a total of 2.27 inches going back to June 8. Elsewhere, a few broad areas recorded at least 2 inches for the week, including most of the Gulf Coast, southern Alabama, central and southern Georgia, the northern half of Florida, a large stripe through central and adjacent eastern Texas, central through southeastern Oklahoma, and in numerous patches from southeastern Colorado and much of Kansas through southeastern Nebraska, portions of Iowa, northern Missouri, northern Illinois, and the central to southern Great Lakes Region. In some of the wetter locations across the central Plains and adjacent Front Range, impacts improved substantially enough to justify 2-cagegory improvements on the Drought Monitor. Meanwhile, several patches across northern Arkansas, southeastern Missouri, and the adjacent Lower Ohio Valley also received 2 or more inches of rain. Moderate totals exceeding 0.5 inch, with localized totals topping 2 inches, affected areas from the central High Plains and southern half of the Great Plains eastward and northeastward through much of the Mississippi and Lower Ohio Valleys, the central and southern Great Lakes, the Southeast, the Mid-Atlantic Region, and the St. Lawrence Valley. Meanwhile, light precipitation at best was observed through most of the Northeast, the Upper Ohio Valley, the far Upper Mississippi Valley, the northern Great Plains, and most areas from the High Plains to the Pacific Coast outside Kansas, Colorado, and northern New Mexico. Many existing areas of drought that were impacted by the heavy precipitation experienced marked relief, but despite expansive areas receiving little or no measurable precipitation, drought intensification was limited in extent, largely due to the lower temperatures and the typical autumnal decline in human and environmental water demand.
Severe drought (D2) was introduced across the northern half of Maine following a few tenths of an inch of precipitation last week and slowly deteriorating surface moisture conditions. Similarly, declining streamflows led to moderate drought (D1) expansion through northern sections of New Hampshire and adjacent Vermont. Farther south, the trend observed periodically over the past several months continues, with coverage of abnormal dryness and moderate drought (D0-D1) continuing to slowly erode. Moderate drought was removed from southeastern New Hampshire while D0 was pulled out of south-central New Hampshire, parts of Delaware and southeastern Maryland, and Lower Southern Maryland. Despite a few episodes of heavy precipitation over the past several weeks, D1 is maintained in northeastern and southeastern sections of Massachusetts due to several wells showing near-record-low groundwater levels and quickly-declining streamflows noted in the wake of heavy precipitation events, suggesting the moisture budget remains deficient beyond surface to root zone moisture.
Southeast
Widespread heavy rains exceeding 2 inches, with broad swaths receiving 5 to locally 10 inches, supported widespread 1-category improvements across southern Alabama, the Florida Panhandle, southern Georgia, coastal South Carolina, and the eastern tier of the Florida Peninsula. Farther north, heavy precipitation was spottier, and therefore only relatively small patches of improvement were introduced. A few areas missed out on the moderate to heavy precipitation, resulting in some modestly-increased precipitation deficits and worsening dryness impact indicators like streamflow. This prompted some deterioration in the depiction across a few relatively small areas in southeastern Virginia, northeastern North Carolina, central South Carolina, and the northern half of Georgia. Farther south, across the central and western Florida Peninsula, generally moderate rainfall was observed, keeping dryness and drought intensities unchanged in most locations.
South
A variable precipitation pattern was observed across Tennessee and the Lower Mississippi Valley last week, resulting in some areas of nominal improvement (scattered across eastern Tennessee, southeastern Louisiana, southern Mississippi, and northern and northwestern Arkansas) and other areas of somewhat increased moisture deficits and deterioration (scattered across central and western Tennessee, southern and eastern Arkansas, northern Mississippi, and central through southwestern Louisiana). Farther west, across Texas and Oklahoma, broad areas recorded heavy to excessive precipitation, resulting in several sizeable areas of widespread improvement. Multiple inches of rain – for the second consecutive week in some areas – induced improvements across most of southeastern and Deep South Texas, and in a swath from central Texas through much of the Red River (South) Valley into central Oklahoma. Farther west, across the Big Bend and the Texas and Oklahoma Panhandles, light to moderate precipitation following the excessive amounts recorded last week led to widespread one-category improvements. Enough precipitation was observed to support 2-category improvements at a few locations in Deep South Texas, south-central Oklahoma, and the western Oklahoma Panhandle. There were a few patches in southwestern Texas and the northern interior missing the heavy precipitation that hit most locations over the past couple of weeks, resulting in scattered spots of deterioration. Improvement was far more common across Texas and Oklahoma, however, as opposed to the mixed bag of changes noted farther east.
Midwest
Dryness and drought continued affecting the southern and northern tiers of the region this past week while persistently wet weather over the past few months has a void of dryness and drought stretching from Iowa and northern Missouri eastward north of the Ohio River and south of the Great Lakes States. Moderate to locally heavy precipitation (1 to locally 2.5 inches) fell on the dry areas across the central Lower Peninsula of Michigan, removing most of the moderate drought there and reducing D0 coverage slightly. Farther north, only light precipitation was noted across northern Wisconsin, the Upper Peninsula of Michigan, and adjacent areas, resulting in broad 1-category deterioration. Exceptional Drought (D4) expanded in coverage across northern Wisconsin, and D2 conditions were brought into a large part of the Upper Peninsula of Michigan. To the west, drought remained essentially unchanged over most of Minnesota, with only isolated changes noted. Along the southern tier of the Midwest Region, continued subnormal precipitation allowed for areas of deterioration across central and eastern Kentucky and parts of southern Missouri while locally higher amounts prompted limited improvement in some locales near the Mississippi/Ohio Confluence and west-central Missouri.
High Plains
Widespread heavy precipitation abetted robust improvement across eastern Colorado, central and western Kansas, and parts of southern Nebraska. Numerous locations reported 3 to locally over 6 inches of rain, which was sufficient to support 2-category improvements in portions of southeastern Colorado and the western half of Kansas. Precipitation amounts declined abruptly north of a line from central Colorado through northeastern Nebraska, and only a few tenths of an inch at best was observed beyond this delineation. Still, improvements were introduced in parts of the central and northern Dakotas where earlier precipitation may have been more beneficial than initially assessed. The only areas of deterioration noted were in northeastern Colorado and part of north-central Wyoming, which consistently have been north and/or west of the heaviest precipitation. Elsewhere, dryness and drought intensities did not markedly change from last week.
Moderate to heavy precipitation (0.5 to locally approaching 2.0 inches) fell early in the period across north-central and northeastern New Mexico, but conditions were quiet across the rest of the West Region. There were scattered small areas reporting a few tenths of an inch of precipitation last week, primarily in Montana and the lower Four Corners States, while most sites observed no measurable amounts. But despite the predominantly dry week, fairly substantial areas of improvement were noted as the environmental response to earlier above-normal to heavy precipitation continued. Improvement was most common this week across New Mexico, Arizona, and Montana, with a few areas also noted in southeastern Idaho and Utah. Across almost all of Nevada, Idaho, and the three West Coast States, dryness and drought were essentially unchanged from the prior week.
Scattered moderate rains affected the Commonwealth last week, perpetuating the trend in recent weeks for improvement to outpace deterioration. Dryness eased its grip on some areas in the north-central, eastern, and southwestern Puerto Rico while other locations were not significantly different than one week prior.
Early in the drought week (Wed, Sep 30 – Tue, Oct 6, 2026), synoptic drivers for the weather conditions observed across the islands included an upper-level low pressure system positioned northeast of the USVI with upper-level convergence across the forecast area, inhibiting the development of deep thunderstorm activity. By mid-period, showers were noted to pass over the islands with the main trough now west of the area over Hispaniola. Conditions aloft over the USVI gradually became less favorable for strong convection as temperatures warmed and mid-level lapse rates weakened. The heat threat was more prominent towards the end of the drought week, along with an increased risk of afternoon thunderstorms.
Weekly estimated rainfall amounts from satellite-based NASA SPoRT (GPM IMERG) data ending Oct 6th at 1200 UTC ranged from near zero to about 0.8-inch, with somewhat higher amounts indicated over Puerto Rico (several inches), especially the western portion of the Commonwealth.
At St. Croix, precipitation amounts in descending order included: VI-SC-35 (Frederiksted 1.3 ENE, 1.66 inches, 6 days of data), VI-SC-20 (Frederiksted 1.7 ESE, 0.66-inch), VI-SC-10 (Christiansted 1.6 E, 0.39-inch), VI-SC-23 (Christiansted 6.5 W, 0.38-inch, 5 days), VI-SC-29 (Frederiksted 2.5 NNE, 0.37-inch), VI-SC-37 (Frederiksted 5.6 E, 0.30-inch, 5 days), VI-SC-32 (Frederiksted 1.9 NNW, 0.30-inch, 3 days), VI-SC-30 (Christiansted 1.7 SW, 0.25-inch), VI-SC-25 (Christiansted 4.4 W, 0.14-inch), and VI-SC-24 (Christiansted 2.1 ENE, 0.04-inch, 1 day). The Adventure 28 Well water level varied between 26.30 feet and 26.64 feet below the land surface during this period. At East Hill (#672560) the Standardized Precipitation Index (SPI) at 1, 3, 6, 9, and 12-months were, respectively: -1.67, -2.22, -2.35, -1.3, and -1.7. This is consistent with D3/D4 conditions and if next week continues to be abnormally dry, St. Croix’s drought depiction may be degraded further to D4.
Rainfall totals at St. John ranged from 0.62-inch at VI-SJ-5 (Cruz Bay 1.6 E) to 0.02-inch at VI-SJ-10 (Cruz Bay 3.1 NNW). Intermediate amounts included 0.05-inch at VI-SJ-11 (Coral Bay 0.7 NW, 4 days of data), 0.10-inch at VI-SJ-8 (Cruz Bay 7.4 E, 2 days of data), and 0.15-inch of rain at VI-SJ-3 (Windswept Beach). In addition, Windswept Beach reported a total of only 2.63 inches of precipitation for the entire month of September. The drought has stretched out to 5 months now, from May through September 2026. Each of those 5 months has featured a rainfall deficit (compared to the 1984-2025 mean value) greater than 2 inches, which totals 13.22 inches. The well-water level at the Susannaberg Dpw 3 Well showed a steady decline throughout the period, from 19.11 feet below the land surface at the start to 19.35 feet at the end of the period. The SPI values at Windswept Beach (VI-SJ-3) at (1, 3, 6, 9, and 12-months) are, respectively: -2.26, -1.72, -2.17, -1.22, and -1.76. These values are comparable to those at the shorter 1- and 3-month periods for St. Croix, and if deterioration continues next week, St. John’s drought depiction will also be degraded from D3-S to D4-S.
At St. Thomas, an even half-inch of rain was reported at VI-ST-5 (Charlotte Amalie West 4.2 WNW) and 0.41-inch at VI-ST-15 (Charlotte Amalie West 1.3 N). The groundwater level at the Grade School 3 Well began the period at 9.26 feet below the land surface, and finished at 8.98 feet near the very end of the period. It appears that some rain fell on Oct 3 (assuming no human water management was involved), boosting the well water level to 9.06 feet by the middle of that afternoon. The water level gradually declined thereafter until the late evening of Oct 6, when another shower boosted the well level to 8.98 feet. This week, St. Thomas retains its D4-S designation.
Pacific
Moderate to heavy precipitation was reported across Southeast Alaska, but this is a wet time of the year there, and moisture deficits have been slow to improve. As a result, D0 conditions are unchanged there from last week. Farther north, no changes were supported across the D0 and D1areas in east-central Mainland Alaska despite spotty precipitation.
Episodes of heavy to excessive precipitation over the past several months have removed drought from the island chain, but a stubborn area of abnormal dryness (D0) has been hanging on across leeward locations on the Big Island. This week, a variety of indicators improved sufficiently to remove the southern reaches of the D0 area, but lingering precipitation deficits remain intact along most of the western tier of the Big Island.
At the beginning of the drought week (Wed, Sep 30 - Tue, Oct 6, 2026), Invest 93 brought showers and thunderstorms to the Marianas. Western portions of Micronesia were dominated by monsoonal showers and thunderstorms, while eastern areas experienced mostly clear to partly cloudy skies. By Friday evening, Oct 2, strong to gale-force southwesterly winds prevailed across the Marianas, largely influenced by the outgoing Tropical Storm Choi-wan (26W) and enhanced monsoon surge from the southwest. By late in the period, Choi-wan (26W) had intensified into a super-typhoon as it continued to exit the CNMI (Commonwealth of the Northern Mariana Islands) region well to the north. The southwestern monsoon surge had weakened, accompanied by slowly improving marine conditions. By early Monday evening, Oct 5, super-typhoon Choi-wan (26W) was located well east-northeast of Iwo Jima. Maximum sustained winds of 155 mph were reported by JTWC earlier in the day. Typhoon Nolo (15E) recently crossed the Date Line from the Central Pacific and was continuing to move westward at a fairly moderate clip (17 mph), with peak sustained winds of 115 mph. Tropical Depression Koguma (27W), formerly known as JTWC’s Invest 94, was centered over the northern Republic of the Marshall Islands (RMI). Koguma strengthened into a Tropical Storm shortly thereafter and by early Tuesday afternoon was centered 315 miles NNW of Kwajalein atoll near 13N/167E. Finally, in western Micronesia, the monsoon surge remained the dominant feature in the region, and was located over Palau and Yap early Monday evening, Oct 5, producing thunderstorms, showers, and gusty winds. In the South Pacific, showers embedded within the easterly wind flow continued to move across the islands from time to time. Surface high pressure to the south of American Samoa will continue to promote this easterly flow pattern, while keeping a trough to the north of the region at bay.
NASA SPoRT (GPM IMERG) satellite-based estimated rainfall totals for the past 7-days ending 12 UTC on Oct 6 indicate about 1-inch has generally fallen around Palau (though very localized 5-6 inch amounts were measured by ground-based rain gauges) and the western Federated States of Micronesia (FSM), with embedded pockets of 1-2 inches. A broad arc of 1-8 inch precipitation amounts was depicted from the CNMI eastward and southeastward to the RMI, with most of the heavier 4-8 inch totals concentrated in the vicinity of the CNMI. A large portion of the central FSM reported an inch or less of precipitation for the week. South of the equator, rainfall amounts were generally under 0.75-inch across American Samoa.
Tropical cyclones and monsoon surges ensured Guam and the CNMI had enough rainfall this past week not only to meet minimum weekly water requirements (1-inch or greater) but also monthly thresholds (4-inches or greater). According to xmACIS2 data, Dededo received the jackpot this week with 7.41 inches of rain (7 days of data). Something of note is that Dededo’s total September rainfall was 14.92 inches, which is interesting being just 10 days or so away from Columbus Day. Other totals for the week in descending order are: Guam (6.23 inches), Saipan International Airport (5.87 inches, 5 days of data), Rota Airport (5.47 inches), and Tinian (4.50 inches, 5 days of data). Guam and the CNMI remain dryness and drought-free.
The Republic of Palau measured 5.92 inches of rain at WSO Palau (Airai) and 5.01 inches of rain (6 days of data) at Koror. Given these amounts, Palau’s drought designation was improved from D1-S to D0-S this week.
Precipitation measurements taken across the Federated States of Micronesia (FSM) that reached or exceeded weekly minimum water requirements (2 inches) included (in descending order): Gilman (3.24 inches), Kapingamarangi (2.75 inches, 6 days, stays D1-S), North Fanif (2.13 inches), Ulithi (2.12 inches, 5 days), and Nukuoro (2.02 inches, 6 days). The locations that came in short of the 2-inch minimum requirement included: Rumung (1.82 inches, 6 days), Yap Island (1.62 inches, 6 days), Kosrae (1.29 inches, though only 2 days of data were available), Woleai (1.27 inches), Chuuk (0.14-inch), Lukunoch (0.04-inch, 6 days), and Pohnpei (Trace, 6 days). No data was available this week for either Fananu or Pingelap. No changes were made to any of the station designations within the FSM this week.
The Republic of the Marshall Islands (RMI) reported several stations that reached or surpassed the weekly minimum rainfall requirement this week. These include: Majuro (4.66 inches), Mili (2.97 inches, 3 days) and Kwajalein (2.21 inches). The stations that did not receive adequate rainfall this week included Jaluit (1.45 inches, 6 days), Utirik (1.25 inches), Wotje (1.13 inches, 5 days), and Ailinglaplap (1.02 inches, 6 days). All drought designations remain dryness and drought free.
In American Samoa, precipitation amounts for the week ranged between 0.40-inch at Toa Ridge to 0.50-inch at Siufaga Ridge, with an intermediate value of 0.44-inch (6 days) at the Pago Pago Airport. Tutuila retains its D0-S designation this week.
Looking Ahead
During October 7-12, Tropical Storm Isaias in the southwestern Gulf is expected to intensify into a category-2 hurricane and head northeastward and then northward toward the United States. After peaking in intensity and beginning to weaken, landfall is expected somewhere along the north-central or northeastern Gulf Coast late October 9. Once inland, Isaias should weaken more quickly as the remnant circulation tracks northward into the Southeast or adjacent Lower Mississippi Valley. Sustained winds are expected to peak around 105 mph in the northern Gulf, but with weakening expected to start prior to landfall up to a couple hundred miles inland. A surge of tropical moisture is expected to accompany Isaias into the Southeast, bringing moderate to heavy rains into the region, reaching as far northward as the Ohio Valley and Mid-Atlantic Region. By the end of the period, upwards of 7 inches of rain are expected in a few parts of the Florida Panhandle, and amounts exceeding 3 inches are forecast as far north as northern Alabama and adjacent areas in Mississippi and Georgia. Most areas along the Carolinas Coast are also expected to receive over 3 inches of rain. Farther west, another push of tropical moisture into the interior West could bring 3 to 6 inches of precipitation to isolated spots in the higher elevations of northeastern Utah and west-central Wyoming. At least 1.5 inches of rain are anticipated from central Mississippi eastward, reaching as far north as the Tennessee Valley, southern Appalachians, and Mid-Atlantic Region. Scattered locations in the higher elevations of the interior West and southern California Coastal Ranges are also forecast to record over 1.5 inches of precipitation by October 12. Moderate amounts exceeding 0.5 inch should cover southernmost Florida along with the greater Ohio Valley, most of the Appalachians, central and southern New York, and southern New England. Many lower elevations across the interior West are also expected to see at least 0.5 inch. In contrast, little or no precipitation is expected in many areas impacted by dryness and drought, including the Far West to the north and west of the Sierra Nevada, most of the Plains and Great Lakes Region, and western reaches of the Lower Mississippi Valley. Above-normal temperatures are anticipated across a broad swath of the Nation’s Midsection from the southern and central Plains through the Mississippi Valley and the Great Lakes Region. Daily high temperatures are expected to average at least 4 deg. F above normal there, with anomalies exceeding +10 deg. F from north-central Texas through most of Oklahoma and adjacent parts of Kansas, Missouri, and Arkansas. Farther west, most locations from the northern and western Rockies to the Pacific Coast are expecting below normal temperatures, along with most of Montana. Daily highs are expected to average at least 3 deg. F below normal from the Cascades southward and eastward, with anomalies of -8 to -12 deg. F forecast in the northern Great Basin, northern Rockies, and High Plains of Montana.
Wetter than normal conditions are expected over the ensuing 5 days (October 13-17) across a large part of the Contiguous U.S. from the Rockies and northern High Plains eastward through New England, the Mid-Atlantic Region, the southern Appalachians, and the Florida Panhandle. The best odds for unusually heavy precipitation extend from the central and lower Four Corners Region eastward through Texas, the Red River (South) Valley, and the western Lower Mississippi Valley. At least marginally enhanced chances for surplus precipitation also cover all of Alaska and Hawaii. Only west-central and northern California and southwestern Oregon have nominally increased chances of subnormal precipitation. Meanwhile, above-normal temperatures are favored across much of the Pacific Northwest and over a large area including the Southeast, central and southern Appalachians, southern Great Lakes Region, Middle and Lower Mississippi Valley, central and southern Great Plains, and southern High Plains. Warmer than normal conditions are also favored across Hawaii and the central and eastern sections of Alaska. Increased odds of below-normal temperatures are limited to the Northeast and New England.
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