Drought — Sherman, Nebraska

2023-10-01 to 2023-10-30 · Sherman, Nebraska

Wider weather episode

During October 2023, at least parts of 20 of the 24 South Central Nebraska counties spent at least the majority of the month assigned at least Severe Drought (D2) by the U.S. Drought Monitor (USDM), with roughly half of the domain mired in at least D2 throughout the month as a long-term drought situation lumbered on. October marked the 21st-consecutive month with at least D2 plaguing portions of the local area, the 15th-straight month with at least Extreme Drought (D3) afflicting some locations, and the seventh-consecutive month with worst-off Exceptional Drought (D4) maintaining its grim grasp across various eastern counties. For the 24-county area as a whole, October was not a great month precipitation-wise, as roughly three-fourths of South Central Nebraska registered below normal totals. That being said, much of the roughly one-fourth of the area that enjoyed above normal precipitation was pretty solidly above normal, actually triggering a decent areal coverage of one to two category improvement especially within several far northern/western counties (see below for more specific monthly precipitation details). Focusing on October county-level USDM drought category specifics, and somewhat oddly given the prevailing drier-than-normal conditions, official USDM drought categories during the month either maintained status quo or featured one to two category improvement (there was no degradation during the month). Diving deeper into the details, the month opened with the drought situation as follows: 1) Worst-off D4 encompassed at least parts of all counties east of Highway 281, along with portions of Hall/Adams counties (comprising roughly 22% of South Central Nebraska)...2) A buffer zone of D3 surrounded the D4 zone, with the combined D3+D4 areas dominating much of the eastern half of the area...3) The majority of the remainder of South Central Nebraska (including most of the western half) was a varied mix of D2/D1...4) Abnormally Dry (D0) was assigned to parts of several southwestern/west-central counties, including the majority of Harlan, Franklin and Gosper (making up roughly 14% of South Central Nebraska)...5) The majority of Furnas, Phelps and southern Gosper counties was deemed void of all drought (including D0)...but this contained only around 7% of South Central Nebraska. As October unfolded, there were primarily two rounds of fairly widespread rainfall/thunderstorm activity, one on the 3rd and another on the 12th (with the latter event's heaviest rain focused within the northwest half of the area). As a result of primarily these two rounds of activity, along with a more localized, narrow swath of appreciable precipitation that targeted primarily Valley, Greeley, Sherman and Gosper counties on the 26th, at least portions of several, mainly northern/western counties saw at least one-category improvement during October. More notably, portions of primarily the following counties enjoyed two-category improvement: Valley, Greeley, Sherman, Howard, Dawson. Thus, at month's end the USDM depicted the following breakdown across South Central Nebraska: 1) Worst-off D4 remained unchanged, still enveloping at least portions of all counties east of Highway 281, along with parts of Hall/Adams counties (accounting for roughly 22% of the total area)...2) The buffer zone of D3 also remained unchanged, with the combined D3+D4 areas still in command of much of the eastern half of the domain and impacting roughly 42% of South Central Nebraska...3) The areal coverage of Severe Drought (D2) shrunk noticeably during the month, now only assigned to a handful of counties mainly along the Highway 281 corridor along the western fringes of the D3 zone (and only accounting for roughly 8% of the total area)...4) The areal coverage of Moderate Drought (D1) also shrunk appreciably, now only including a narrow stripe cutting through several central counties along the western fringes of the D2 zone (and also only comprising roughly 8% of South Central Nebraska)...5) Due to the aforementioned reductions in the areal coverage of D2+D1, better-off D0 actually expanded across several counties primarily west of the Highway 281 corridor (now including roughly 25% of the total domain)...6) Like D0, the percentage of the area deemed void of all drought whatsoever also increased, now including the vast majority of Gosper, Furnas, Phelps and Harlan counties, along with at least portions of Franklin, Dawson, Valley, Greeley and Sherman counties (and constituting roughly 17% of South Central Nebraska).

Turning to October 2023 precipitation details, it was an overall-disappointing story across the area as a whole, with roughly three-fourths of South Central Nebraska measuring at least slightly below normal totals (meaning less than roughly 2.02) and around one-fifth of the area tallying no more than half-normal. The bulk of the overall-driest locations were focused within portions of various counties along/south of Interstate 80 and east of Highway 183. In sharp contrast, at least slightly (and localized significantly) above normal precipitation prevailed across primarily the northwestern one-fourth of the area (primarily northwest of a line from Elwood-Ravenna-Fullerton). Per around 160 NWS and NeRAIN/CoCoRaHS observers, some of the lowest October precipitation tallies included: 0.70 near Hampton, 0.72 in Wilsonville, 0.74 in Superior and 0.77 at Central Nebraska Regional Airport (Grand Island). In sharp contrast, some of the very-highest totals (within Valley/Greeley counties) featured: 4.54 nine miles northwest of Ord, 4.43 four miles east of Scotia, 4.19 in Ord and 4.14 in Greeley. Finishing with a quick-stat highlighting the ever-worsening, longer-term drought situation within the eastern half of South Central Nebraska, and focusing on one of the driest (versus normal) official NWS stations since early-2021: Grand Island (airport) totaled merely 47.46 over the 31-month stretch from April 2021-Oct. 2023...a notable 27.69 below normal/63% of normal.

Source: NOAA Storm Events Database, event_id 1140072. Narrative written by the NWS forecast office that issued the report.