Drought in Nebraska, September 1 to 30, 2023

During September 2023, at least parts of 20 of the 24 South Central Nebraska counties spent the entire month assigned at least Severe Drought (D2) by the U.S. Drought Monitor (USDM), with roughly 60 percent of the domain as a whole mired in D2 throughout the month as a long-term drought situation forged on. September marked the 20th-consecutive month with at least D2 plaguing portions of the local area, the 14th-straight month with at least Extreme Drought (D3) afflicting some locations, and the sixth-consecutive month with worst-off Exceptional Drought (D4) maintaining its dire grasp within various eastern counties. However, on a positive note September rainfall trends were actually fairly encouraging across the majority of the area (most places near to at slightly above normal). Unfortunately though, the primary drier exceptions played out within several eastern counties that were already worst-off to begin with...counties such as York, Polk, Hamilton and northern Fillmore...that entered the month already in widespread D3-to-D4 (see below for more specific monthly precipitation details). Focusing on September county-level USDM drought category specifics, it was a mixed bag overall. While the majority of South Central Nebraska remained stable/unchanged, prevailing above normal rainfall in especially the southwestern quadrant of the area inspired widespread one-category improvement, while below normal amounts in many locales especially east of the Highway 281 corridor prompted one-category degradation. Diving deeper into the details, the month opened with the drought situation as follows: 1) Worst-off D4 encompassed much of Hamilton County and small parts of several nearby counties (but comprising only around eight percent of South Central Nebraska)...2) A sizable swath of D3 (encompassing roughly 35% of the area) persisted over the majority of counties along/east of Highway 14 (along with large portions of mainly Adams/Hall counties along Highway 281)...3) The majority of the remainder of South Central Nebraska was under a varied mix of D2 and Moderate Drought (D1)...4) The best-off Abnormally Dry (D0) category included the majority of Furnas and Phelps counties, along with smaller parts of several neighboring counties. As the month got underway, the first few USDM issuances featured almost zero change. However, the September 19th USDM issuance brought a decent expansion of D4 within parts of several counties mainly east of Highway 281. Then, due in large part to a widespread heavy rain event that occurred Sept. 21-22, the Sept. 26th USDM brought one-category improvement to most locations south of Interstate 80 and west of Highway 281. This included the outright-removal of all drought assignment (including Abnormally Dry D0) from most of Furnas, Phelps and southern Gosper counties...marking the first time in 13 months that ANY portion of South Central Nebraska was deemed drought-free. Thus, at month's end the USDM depicted the following breakdown: 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 the eastern one-third of the area and including roughly 42% of South Central Nebraska)...3) The majority of the remainder of South Central Nebraska (including most of the western half) was a varied mix of D2/D1...4) D0 was assigned to parts of several southwestern/west-central counties, including the majority of Harlan, Franklin and Gosper (including 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.

Turning to September 2023 rainfall details, it was an overall-positive story across the area as a whole, with most places registering near-to-slightly above normal totals. More specifically, around 55% of South Central Nebraska had above normal amounts (roughly more than 2.07), with at least 70% of the area measuring at least 75% of normal (roughly at least 1.55). The majority of the domain (around 80% of it) recorded somewhere between 1.15-3.60 inches....generally 55-175% of normal. Unfortunately, the roughly 30% of South Central Nebraska that picked up less than 75% of normal was heavily concentrated in east-central counties...particularly York, Polk, Hamilton and northern Fillmore. Per around 170 NWS and NeRAIN/CoCoRaHS observers, some of the highest September rainfall tallies featured: 5.29 near Elwood, 4.79 four miles south of Shickley, 4.73 at Kearney airport and 4.41 six miles south-southeast of Lexington. In sharp contrast, among some of the lowest September tallies were: 0.74 four miles east of Waco, 0.88 near McCool Junction and also three miles west of Gresham, and 0.92 three miles south-southeast of Grafton. Wrapping up with a quick stat highlighting the much-longer-term drought situation, and focusing on one of the driest (versus normal) official NWS Cooperative Observer sites since early-2021, Hebron totaled only 56.12 during the 30-month stretch from April 2021-Sept. 2023...a notable 29.12 below normal/66% of normal.