Most of the eastern half of the 48 Contiguous States received little or no rain last week. The only exceptions were across the eastern tier of the Florida Peninsula (over 2 inches in some areas), the Upper Mississippi Valley and northern Great Lakes Region (a few tenths to nearly an inch), and parts of coastal southeastern Texas (a few tenths to a little over an inch). Seasonably cool weather accompanied the fair weather across the northern half of the region, limiting drought intensification there. Warmer weather farther south led to broader areas of deterioration from the southern half of the Mississippi Valley eastward through the lower Mid-Atlantic. Farther west, moderate to heavy precipitation fell from the northern Great Plains to the southern High Plains and westward to the Pacific Coast. Some lower elevation locations, parts of the lower Colorado Valley, and parts of the northern Rockies recorded only light amounts to a few tenths of an inch, but amounts of at least 0.5 inch were observed elsewhere. The largest amounts (over 2 inches) fell on central and southeastern sections of the Four Corners Region, the higher elevations of southern California, the Pacific Northwest from the Cascades westward to the coast, and scattered locations across the higher elevations from western Montana southward through portions of Idaho, northern Utah, and far western Wyoming. Between 4 and 8 inches were observed in some areas near the Colorado/New Mexico border. This continued a pattern of heavy precipitation across much of the Four Corners Region, and significant further improvements were introduced in a large part of this area, with some 2-category improvements introduced across the wettest parts of southern Colorado.
Very little precipitation was observed in the Northeast Region last week. This resulted in a few areas of deterioration, although heavy precipitation prior to the past 1 to 2 weeks kept widespread dryness and drought intensification at bay. D0 was expanded through parts of northeastern Pennsylvania and central Upstate New York, along with a swath covering part of northwestern New Jersey. Most other locations were left unchanged, except for some expansion of D2 conditions across central Maine. Currently, D2 to D3 conditions are limited to the state of Maine, and outside there D1 is confined to a few small areas across the northern and southern parts of the Northeast Region.
Southeast
The eastern half of the Florida Peninsula received at least moderate precipitation last week (several tenths of an inch to locally over 2 inches), but most other locations in the Southeast Region saw little if any precipitation. Prior to the past 1 to 2 weeks, heavy precipitation had fallen on large parts of the Southeast Region, which limited the amount of deterioration introduced this week. Most areas maintained status quo, but pockets of deterioration were introduced in portions of northern and southern Georgia, central South Carolina, eastern North Carolina, and southern Virginia, which did not receive quite as much precipitation as other locations in the Southeast had recorded.
South
Over the past 2 to 4 weeks, different parts of the South Region have trended in markedly different directions. Heavy precipitation has been observed at times across western parts of the South Region, more specifically the central and western sections of Texas and Oklahoma. Areas of additional rainfall during this past week led to further improvements in conditions, some areas near the West Region free of dryness and drought. In contrast, rainfall has been much more sparse farther east, and another week of abnormally dry and warm weather led to broadscale deterioration across the Lower Mississippi Valley, Tennessee, and some of the eastern fringes of Oklahoma and Texas. D3 to D4 conditions now dominate a large part of this region across central and western Tennessee, Arkansas, Louisiana, and some adjacent areas, including northern and west-central Mississippi. Over the past 4 months, most locations across Arkansas, Louisiana, Mississippi, and southwestern Tennessee have recorded 8 to 16 inches less precipitation than normal, or generally less than half of normal.
Midwest
Light to moderate precipitation (several tenths of an inch to slightly more) fell on the northwestern Great Lakes Region, most of Minnesota, and northwestern Iowa while the vast majority of the Midwest Region recorded little or no precipitation. The drying trend of the past few weeks has led to increases in dryness and drought coverage and intensity through much of the southern and northern tiers of the Midwest Region while several consecutive months with at or above normal precipitation has left a swath across the central part of the region from Iowa and northern Missouri through the northern Ohio Valley mostly free from impactful dryness. The dry and relatively warm week led to some expansion of D1 to D4 conditions in part of the northern Great Lakes that missed the moderate amounts, and fairly broad areas of dryness and drought intensified farther south from southern and eastern Missouri through portions of east-central Illinois and central Indiana. More limited deterioration was also noted along the southernmost tier of Kentucky and near the Mississippi/Ohio Rivers confluence, with D3 to D4 conditions now covering a large swath across central and southern Missouri.
High Plains
Excessive precipitation and areas of flooding were reported across much of central and southern Colorado last week, with at least moderate amounts (over 0.5 inch) common from the western half of Kansas northward through most of Nebraska and South Dakota. Moderate amounts also fell on western Wyoming in association with a pulse of tropical moisture that impacted much of the West. One-category improvements were widespread across the southern half as well as northeastern Colorado, along with central through northeastern Nebraska and southeastern South Dakota. In portions of south-central and southwestern Colorado where several inches of precipitation were observed, there were a few fairly broad areas where 2-category improvements were introduced. Elsewhere, dryness and drought did not change significantly enough to support improvements.
Light to moderate precipitation was widespread across almost the entire West Region last week, with locally excessive amounts (2 to locally 5 inches) reported in much of northern and eastern New Mexico, central Arizona, southeastern California, the Pacific Northwest from the Cascades to the coast, and southwestern California. Moisture surged northward out of the Four Corners Region at times, bringing widespread moderate to locally heavy precipitation for much of Utah, Idaho, and western Montana. The driest areas last week were in Washington and Oregon east of the Cascades, southeastern Montana, and the Desert Southwest, where up to a few tenths of an inch fell. The continued pattern of robust precipitation through most of the West Region led to continued improvement to dryness and drought. The most widespread improvement was noted across New Mexico (where localized flooding was reported), central and northern Arizona, and a large part of Nevada due to the wet pattern observed the past few weeks. Improvements were also noted in parts of the lower Colorado Valley, southern Utah, southern Idaho, and portions of central and western Montana. Long-term moisture deficits continue to impact a large part of the region despite the recent uptick in precipitation, so there was not much complete drought removal.
Heavy rain fell on much of the southern tier of the Commonwealth, primarily late in the period. Amounts ranged from 2 to locally 5 inches in southwestern and southeastern sections. This led to some improvements in southeastern Puerto Rico, but the other area affected by heavy rain included areas experiencing D2 and D3 conditions. These areas were not improved at this time due to concerns about longer-term deficits, but the situation will continue to be monitored. Farther north, only light rain (up to a few tenths of an inch) were observed.
Intense drought conditions continued across the U.S. Virgin Islands after another unusually warm and dry week. Drought conditions have been ongoing long enough, and have had a severe enough impact on groundwater levels, to necessitate both short- and long-term drought labels. Conditions on St. John degraded to exceptional drought, where precipitation deficits at 3 and 6 months are highly anomalous. Exceptional drought continued on St. Thomas, where rain amounts were paltry this week. Extreme drought continued on St. Croix, where minimal rain this week worsened precipitation deficits at short- and long-term timescales.
Pacific
Increased precipitation (approaching an inch) last week led to the removal of D1 from part of the southeastern Mainland, but the surrounding D0 area was not changed due to continuing concerns about lingering moisture deficits.
Generally above-normal precipitation has dominated conditions across Hawaii during the past few months, keeping the state free of drought despite a relatively dry week in many areas. Some of the leeward areas across the Big Island continue to evade the wetter pattern, and D0 conditions there were unchanged.
This week in American Samoa, short-term abnormal dryness continued, along with reported browning vegetation. Rain at Pago Pago totaled near 0.24 inches, while Siufaga Ridge totaled near 0.6 inches and Toa Ridge received 0.49 inches.
In Palau, short-term moderate drought developed this week, as dry weather continued to cause water shortages. Rain at Koror totaled 0.41 inches this week.
The Mariana Islands remained free of drought or abnormal dryness this week. Rain totaled 1.3 inches at Saipan, 1.15 inches at Rota, 0.88 inches at Guam and 1.5 inches at Tinian.
The Federated States of Micronesia mostly remained free of drought or abnormal dryness, with a few local exceptions. The last couple of weeks on Yap have been drier, with 1.61 inches of rain last week and 1.4 inches this week, though wet conditions in the weeks prior are keeping any abnormal dryness at bay. Ulithi finished the week with only 0.21 inches of rain, making this three weeks in a row with less than 2 inches there as well. However, no abnormal dryness has yet developed given wet weather in September. In Woleai, drier weather has also taken hold recently, with 0.66 inches of rain there this week marking the fourth consecutive week with less than 2 inches of rain. Given a consistently (and record) wet September, abnormal dryness has not quite developed, though conditions will continue to be monitored. In Chuuk and Nukuoro, recent weeks have featured a mix of dry and wet weather, and both locations remained free of drought or abnormal dryness. Rainfall in Chuuk totaled 1.79 inches, while Nukuoro received 0.84 inches. Short-term abnormal dryness and moderate drought continued on Lukunor and Kapingamarangi, respectively. On Lukonor, 2.78 inches of rain fell this week, likely improving conditions some, but not enough to overcome a very dry preceding 5 weeks. Kapingamarangi received 0.5 inches of rain, marking the third week in a row with a half inch of rain or less (the preceding two weeks were almost completely dry). In Pohnpei, 3.46 inches of rain were reported and wet conditions continued there following a very wet August and September. In Kosrae, 0.74 inches of rain were reported. No abnormal dryness has developed yet, but given mostly drier weather over the last several weeks, conditions will be monitored closely moving forward. No data were available this week for Fananu or Pingelap, so no USDM depictions were made for either location.
In Ailinglapalap, the last couple of weeks have been drier, with 0.65 inches of rain falling this week. Given wet preceding weather, though, no abnormal dryness has yet developed. In Kwajalein, recent data has been somewhat limited, and 0.94 inches of rain were reported this week (with three days missing from the analysis). Given wet weather across most of September, no abnormal dryness has yet developed, though conditions will be monitored moving forward. Short-term abnormal dryness developed in Jaluit this week, where 0.7 inches of rain fell, marking four weeks in a row with less than 2 inches of rain. Normal conditions continued in Majuro, where this week’s rain total of 0.81 inches snapped a three-week streak of wetter weather. No USDM depictions were made for Utirik, Wotje and Mili, as no data were available for these locations.
Looking Ahead
During the next 5 days (through Nov 2), areas of heavy precipitation (1.5 to locally near 4.0 inches) are expected across central Arizona, the higher elevations of the central Rockies (including parts of Colorado that were inundated this past week), much of the High Plains of Texas, and part of the central Gulf Coast. Moderate amounts (0.5 to locally approaching 2.0 inches) are forecast for most of the higher elevations in the Rockies, a swath from the southern High Plains into the northern Great Plains, and most of the central and eastern Gulf Coast States. A few tenths of an inch with isolated higher amounts are expected across the rest of the U.S., with little precipitation anticipated along the central West Coast, southeastern Texas, the Mid-Atlantic, the Northeast, and the adjacent Great Lakes Region. Daily maximum temperatures are forecast to average 4 to 8 deg. F below normal across the central and western Four Corners, the Great Basin, and much of the Desert Southwest. Meanwhile, most locations from the northern and eastern Great Plains through the Great Lakes Region and across the Mississippi, Ohio, and Tennessee Valleys are expecting warmer than normal conditions, with daily highs averaging 5 to 13 deg. F above normal. The largest anomalies are anticipated across the southern Great Lakes Region.
During Nov 3-7, above-normal precipitation is at least marginally favored over most of the Contiguous U.S., Alaska, and the Big Island of Hawaii. The northern tiers of both Alaska and the western U.S. are the only exceptions, with drier than normal conditions expected from much of Montana through Washington and adjacent Oregon. Meanwhile, above-normal temperatures are also expected to dominate the country, with only parts of the western Hawaiian Islands and the Four Corners Region expected to average closer to normal temperatures.
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