Heavy precipitation again doused the Pacific Northwest, especially across the northern half of the Cascades and along the Washington and northern Oregon Coast. Between 6 and 10 inches of precipitation fell on most of northwesternmost Washington, and 6 to 8 inches fell on most of the northern Washington Cascades and a few areas near the Washington/Oregon border and along the northwestern Oregon Coast. From central Oregon northward, over 3 inches fell on the Cascades and coastal areas while 1.5 to 3.0 inches fell on other locations there from the Cascade Foothills to the Pacific Ocean. Farther east, locally heavy precipitation (1 to locally approaching 4 inches) was observed in northwestern Montana and northern Idaho. Other locations from the Great Plains westward to the Pacific Ocean were much drier, with most locations recording no measurable precipitation. Across the eastern half of the country, moderate to heavy precipitation (1 to locally 4 inches) fell on most of the Northeast, with the heaviest amounts falling on northern New York and in a swath from southwestern New England and the New York City area northward through northeastern New York and adjacent Vermont. Areas around the Outer Banks of North Carolina and southeastern Virginia also recorded heavy precipitation (2 to 4 inches) while amounts ranged from 1 to 3 inches in most of central and eastern Maine, New Jersey, central and eastern Pennsylvania, parts of the Mid-Atlantic region, and across Kentucky, most of Tennessee, and the adjacent Ohio and Mississippi Valleys. The west side of the Middle and Lower Mississippi Valley recorded generally 0.5 to locally 2.0 inches of precipitation, similar to totals reported across the upper Southeast, the central Carolinas, the central Appalachians, and the Upper Ohio Valley. In contrast, little or no precipitation was also observed across most of the Lower Mississippi Valley, near the central and eastern Gulf Coast, over the South Atlantic region from South Carolina through southern Florida, and through the Great Lakes region and adjacent portions of the Midwest.
These conditions led to broad areas of improvement across the Northeast, the Mid-Atlantic region, most of the Carolinas, the central and southern Appalachians, the Ohio Valley, portions of the Middle Mississippi Valley and adjacent Lower Mississippi Valley, a few parts of the central and northern Rockies and southern California, and portions of the Pacific Northwest, where the heavy precipitation did not improve moisture shortages as much as might be expected due to quickly-increasing normal at this time of year. Meanwhile, after the prior week’s beneficial precipitation, low precipitation totals this past week allowed for broad areas of intensification or re-intensification of dryness and drought over most of Texas, southern Oklahoma, the northern Great Lakes, parts of the northern Great Plains, portions of the central High Plains, north-central Montana, and central Maui. A few areas of deterioration were also introduced from southern South Carolina through southern Florida and through parts of the Virginia Piedmont.
Northeast
With moderate to heavy precipitation widespread across most of the Northeast Region, many areas saw improvement on the Drought Monitor map. Still, dryness and drought continued to stretch across an historically unusual amount of the Region. Some degree of dryness or drought (D0+) covered 85.5 percent of the Region, down from 93.4 percent the prior week and the lowest since mid-September (81.1 percent). Drought conditions (D1+) contracted to cover 54.5 percent of the Region, down from 65.3 percent the prior week. And severe to exceptional drought (D2+) coverage dropped to 23.0 percent from 34.3 percent the prior week, also the lowest since mid-September (22.5 percent).
Southeast
Moderate to heavy rain (0.5 to locally over 3 inches) fell from Virginia southward through the central Carolinas, across the Appalachians, and over northern portions of Alabama. From central sections of the Carolinas, Georgia, and Alabama southward through Florida, only a few tenths of an inch fell, if any, with most locations recording no measurable precipitation. Predictably, this resulted in substantial areas of improvement over significant portions of Virginia and North Carolina while areas farther south, especially across southern Georgia and Florida saw conditions persist or worsen. With D3 coverage increasing to cover much of southern Georgia, that state’s coverage of extreme or exceptional drought (D3-D4) jumped to 12.7 percent, the highest in over 6 years (16.1 percent in mid-October 2019). For the Region as a whole, however, improvement was noted in more areas than deterioration despite most of it occurring in two states (Virginia and North Carolina). Some degree of dryness (D0+) reached across 75.5 percent of the Region, down from 81.7 percent the prior week. Drought coverage (D1+) dropped from 54.6 to 48.9 percent – the first time in 3 weeks that drought coverage dropped below 50 percent.
South
Moderate to heavy rain (1 to 3 inches) doused Tennessee, portions of Arkansas, and some adjacent areas last week. Dryness and drought over western Tennessee and much of Arkansas eased a bit as a result. Most other locations across Tennessee, Arkansas, eastern Oklahoma, and northern Mississippi reported several tenths of an inch of rain, and similar totals fell on isolated areas across southern Mississippi, Louisiana, and coastal Texas. The remainder of the Region, including most of Texas and Oklahoma, observed no measurable rain. After beneficial precipitation the prior week, the precipitation-free week allowed dryness and drought to re-intensify or expand over large parts of Texas and southern Oklahoma. After drought coverage (D1+) declined to about one-third of the state the prior week, coverage increased to over 45 percent this past week, which is the greatest extent since early May. Areas of late-season crop stress and some die-off has been reported across Oklahoma and Texas over the past few weeks.
Midwest
Moderate to locally heavy rain (1.5 to 3.0 inches) doused much of Kentucky and northeastern Ohio, but amounts were considerably lower at most locations. Amounts of an inch or a little more fell near the Ohio River and across central Ohio while a few tenths to a little more than an inch was observed over southern sections of Illinois and Indiana, in a swath from Missouri northward through interior Minnesota, and in the northern Great Lakes region. Little or no precipitation was observed over the remainder of the Great Lakes region, eastern Minnesota, central and northern sections of Indiana and Illinois, and northwestern Ohio. Predictably, this precipitation pattern resulted in continued improvement near the Ohio River and across most of Ohio while the dry week engendered persistence or intensification across the northern and central tier of the Region. In particular, increasing 60- and 90-day precipitation deficits prompted significant expansion of moderate drought (D1) across the south-central Upper Peninsula of Michigan, northern Wisconsin, and east-central Minnesota. As a result, even though coverage by some degree of dryness or drought (D0+) dropped from 68.8 to 65.1 percent last week, drought coverage (D1+) actually ticked up slightly from 33.4 to 34.8 percent.
High Plains
The High Plains Region is currently the Region least-affected by dryness and drought even though coverage in sum increased slightly this past week when most of the region reported a few tenths of an inch of precipitation at best. Measurable totals were restricted to eastern Kansas and southeastern Nebraska. The dry week induced a few areas of deterioration, but even so, less than 39 percent of the Region is experiencing some degree of dryness (D0+), and only 17.8 percent is enduring drought (D1+). Precipitation deficits on most time frames crept upward Region-wide, but areas of deterioration were relatively limited given the relatively low natural and human water demand this time of year.
West
Several inches of precipitation pelted central and northern sections of the Cascades and coastal Pacific Northwest, and 1 to 3 inch totals were common across northwestern Montana and northern Idaho, as well as the lower elevations in the Pacific Northwest between the coast and the Cascades. Several tenths of an inch of precipitation were reported farther south along the West Coast and in the lower elevations of the northern Intermountain West, but most of the West Region received no measurable precipitation for the week. This prompted areas of intensification in north-central Montana and southeastern New Mexico while the heavy precipitation led to areas of improvement in the Pacific Northwest. But given how early it is in the wet season and that normals are ramping upward fairly quickly there, improvement in dryness and drought was not as widespread as one might assume. Drought coverage (D1+) in Washington was unchanged from the prior week at 94.8 percent, and the extent of the more intense drought classifications (D2-D4) declined only slightly from 65.1 to 63.9 percent. There was even less change in Oregon, although dryness there is not as widespread as in Washington. Montana reported intensification in north-central parts of the state, but a little improvement farther west, as was the case in the fringes of the D3 and D4 areas in Idaho. According to the U.S. Geological Survey, flows along numerous rivers in the West remain very low. On the Missouri River at Great Falls, MT, in early November, streamflow was observed at 3,620 cubic feet per second, well below the mean for the date since the turn of the century (4,934 cubic feet per second, ranging from 3,880 in 2021 up to 6,470 in 2010). On the Firehole River, near West Yellowstone, MT, streamflow was 212 cubic feet per second in early November, below the 2002-2024 mean of 272 for similar dates, which ranged from 236 in 2022 to 318 in 2008. These amounts are up slightly since late summer. In late August, a field measurement of 193 cubic feet per second was bested only by 192 in early August 2016.
Caribbean
In Puerto Rico abnormal dryness (D0) remained unchanged from last week after some spotty light to moderate rain.
The U.S. Virgin Islands remained free of drought and abnormal dryness this week. Windswept Beach on St. John reported 0.8 inches of rain. On St. Thomas, rainfall amounts reported by CoCoRaHs observers were about a half inch or less. Higher rainfall amounts were reported by observers on St. Croix, with many observers reporting over 1 inch of rain.
Pacific
In Alaska no dryness or drought is currently present.
Precipitation was nondescript across the island chain last week, keeping significant moisture shortages intact over large parts of the state. Dryness and drought is unchanged across most of the state, but some deterioration was introduced in parts of central and northern Maui. Mahi Pono - an agricultural company with a large planting area in central Maui west of Upcountry – has been prohibited from using surface water for its agricultural operations since late August, relying on groundwater pumping instead. Kahalui in north-central Maui has recorded only 0.18 inch of rain since the start of September, compared to a normal just under 1.5 inches. Since the start of the year, 6.75 inches of rain fell on Kahului, just 57 percent of the normal (11.8 inches). Honopou Stream near Huelo, Maui has measured streamflow among the lowest 5 percent on record for half of the days so far this year. For these reasons, extreme drought (D3) was introduced across part of central Maui while D2 expanded into northern Maui to the northeast of Upcountry Maui. Farther east, on the Big Island, unusually low rainfall totals have persisted for many months. Since September 1, Hilo reported 11.58 inches of rain, which is 9.15 inches below normal; and since January 1, the 46.96 inches of rain reported is less than half of normal (95.72”). Honolulu also reports less than half of normal rainfall since the start of September. Lihue has been wetter than normal since September 1, but year-to-date numbers remain well below normal (19.01 inches, compared to a normal of 28.04 inches). Most locations across the island chain are reporting below-normal to much below-normal streamflows.
At Pago Pago, at least 2.79 inches of rain have fallen this week, with four days missing from the analysis. At Toa Ridge, 2.21 inches of rain have fallen this week, while no rainfall data have been available recently from Siufaga Ridge. American Samoa remained free of drought and abnormal dryness this week.
Data were not available at Palau this week, so no USDM depiction was made there.
The Mariana Islands remained free of drought or abnormal dryness this week. Rainfall amounts recorded this week included 1.59 inches at Guam, 2.6 inches at Rota, 1.68 inches at Tinian and 1.84 inches at Saipan.
Short-term severe drought continued this week in Kapingamarangi. Rainfall totaled 2.23 inches this week, which broke a long run of consecutive weeks with less than 2 inches of rain. Yellowing vegetation was reported on the island. Due to missing data, Fananu, Ulithi and Pingelap did not receive USDM designations. All other islands in the Federated States of Micronesia remained free of drought or abnormal dryness. Yap reported 2.52 inches of rain with four days missing. Woleai reported 4.7 inches of rain, with four days also missing there. Chuuk reported 4.77 inches of rain with one day missing. Lukunor reported 3.97 inches of rain with two days missing. Nukuoro reported 3.48 inches of rain with one day missing. Pohnpei reported 3.18 inches of rain with one day missing. Kosrae reported 4.75 inches of rain.
The Republic of the Marshall Islands remained free of drought or abnormal dryness this week. Kwajalein reported 5.79 inches of rainfall with one day missing. Ailinglapalap reported 2.65 inches of rain with two missing days. In Jaluit, 1.51 inches of rain were reported, following over 7 inches last week. In Majuro, 2.35 inches of rain were reported. In Utirik, Wotje and Mili, rainfall amounts were lower to start November, though recent rainfall otherwise was mostly sufficient, so no abnormal dryness has developed. In Utirik, given that a little under 8 inches of rain were reported in October, any developing further dryness there will be monitored.
Looking Ahead
Over the next 5 days (through November 10), the Pacific Northwest is expected to remain relatively wet. Between 3 and 6 inches are anticipated in parts of the Washington and northern Oregon Cascades and far northwestern Washington. Generally 2 to 3 inches are forecast through the rest of the central and northern Cascades, most of coastal Washington, and coastal areas in northwestern Oregon and northwestern California. Elsewhere, moderate to locally heavy precipitation (1 to 2 inches) is anticipated in the remaining areas from northern California to the Canadian Border. Over much of the northern Rockies, in southern Michigan, to the lee of Lake Erie, across northern New York, and over parts of New England. Totals ranging from a few tenths of an inch to about an inch are anticipated across the northern Intermountain West, higher elevations of western Wyoming, isolated parts of the northern Great Plains, portions of the Midwest, the east half of the Great Lakes, most of the Appalachians, the middle and upper Ohio Valley, the central Gulf Coast states, much of the Northeast, and southeastern Florida. Other locations are expected to receive a few tenths of an inch at best, with little or none anticipated in the South Atlantic Coastal Plain, most of interior Florida, the Lower Mississippi Valley, and from the central and southern Great Plains westward into California. Temperatures are forecast to average warmer than normal in the West and cooler than normal in the East. A shot of cold air – the coldest of the season so far – should push through the East early next week. It will not linger for long, but on one or two nights temperatures could approach freezing as far south as the central Gulf Coast, and readings in the 50’s deg. F may reach into the southern Florida Peninsula. For the 5 days overall, high temperatures are expected to average 5 to 8 deg. F below normal from the Great Lakes and Midwest southeastward into northern Florida. In contrast, daily highs from the High Plains to the Pacific Coast should average 5 to 12 deg. F above normal, with the largest departures expected in parts of the Great Basin, near the California/Oregon border, and over the northernmost Rockies.
The 6- to 10-day outlook from the Climate Prediction Center for November 11-15 favors subnormal precipitation for most areas from the Great Plains to the Atlantic Coast, except along the northern tier of the region. Odds for unusual dryness exceed 50 percent from the Lower Mississippi and Ohio Valleys eastward through the South Atlantic States outside southern Florida. Abnormally wet weather is favored from the High Plains to the Pacific Coast, with chances for unusually heavy precipitation exceeding 60 percent across central and southwestern California. Wet weather is also somewhat favored through Hawaii and over most of Alaska. Temperatures are expected to average below normal in the East from the lower Great Lakes, Middle Ohio Valley, and central Gulf Coast eastward to the Atlantic Coast. The likelihood for subnormal temperatures exceeds 70 percent from northern Florida northward along the Coastal Plain into southern New England. From roughly the Mississippi River to the Pacific Coast, warmer than normal weather is favored, with odds topping 70 percent across a broad area covering most of the central and southern Rockies and High Plains. Warm weather is also expected over most of Alaska and across Hawaii.
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