
Heavy to excessive rainfall is expected today into Wednesday over New Mexico into far west Texas. Flash flooding and debris flows in wildfire burn areas will be possible. A strong coastal storm will develop off the Mid-Atlantic coast Wednesday, intensifying toward southern New England this weekend. Significant coastal flooding, strong rip currents, and beach erosion from high surf expected. Read More >
Overview
A slow-moving upper-level disturbance produced several rounds of showers and thunderstorms across the Black Hills and adjacent plains over the 2018 Memorial Day weekend. This led to locally heavy rainfall and flooding, particularly near Newcastle in northeastern Wyoming and across portions of Fall River County in South Dakota.
Flooding
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| Estimated precipitation between May 28-30 |
Images
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Newcastle, WY, near Cambria Creek |
Culverts on Oil Creek Road, Weston County, WY |
Debris flow remnants, Big Plum Creek Road, Weston County, WY |
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Weston County, WY, outside of Newcastle |
Weston County, WY, outside of Newcastle |
Weston County, WY, outside of Newcastle |
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Fall River County, SD |
Fall River County, SD |
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Rain Reports
| Location | State | 4-day Total (5/27-30/18) | Source |
| Newcastle 3.5 E | WY | 4.45 | CoCoRaHS |
| Newcastle 0.8 ESE | WY | 3.71 | CoCoRaHS |
| Newcastle 26.2 WSW | WY | 3.58 | CoCoRaHS |
| Newcastle 13.0 SSW | WY | 3.58 | CoCoRaHS |
| Newcastle 1.0 W | WY | 3.55 | CoCoRaHS |
| Newcastle 1.7 SW | WY | 3.42 | CoCoRaHS |
| Wind Cave | SD | 3.5 | NWS Cooperative Observer |
| Newcastle 12.5 NNW | WY | 2.89 | CoCoRaHS |
| Rapid City 6.3 SW | SD | 2.84 | CoCoRaHS |
| Custer | SD | 2.84 | NWS Cooperative Observer |
| Oral | SD | 2.79 | NWS Cooperative Observer |
| Rapid City 5.4 SW | SD | 2.68 | CoCoRaHS |
| Rapid City 2.0 SSE | SD | 2.56 | CoCoRaHS |
| Hill City | SD | 2.51 | NWS Cooperative Observer |
| Spearfish 6.7 NNW | SD | 2.48 | CoCoRaHS |
| Moorcroft 11.9 ENE | WY | 2.47 | CoCoRaHS |
| Upton 18.8 SW | WY | 2.37 | CoCoRaHS |
| Hill City 8.4 WNW | SD | 2.36 | CoCoRaHS |
| Whitewood 4.2 NNW | SD | 2.35 | CoCoRaHS |
| Lead 5.5 SSW | SD | 2.35 | CoCoRaHS |
| Upton 11.5 E | WY | 2.32 | CoCoRaHS |
| Rapid City 3.9 S | SD | 2.32 | CoCoRaHS |
| Hot Springs 0.5 SSW | SD | 2.31 | CoCoRaHS |
| Hermosa 6.2 W | SD | 2.31 | CoCoRaHS |
| Pactola Dam | SD | 2.25 | NWS Cooperative Observer |
| Custer Airport | SD | 2.25 | ASOS |
| Beulah 6.1 SW | WY | 2.24 | CoCoRaHS |
| Wright 0.8 ENE | WY | 2.22 | CoCoRaHS |
| Edgemont 14.2 NE | SD | 2.22 | CoCoRaHS |
| Gillette 13.9 NNW | WY | 2.21 | CoCoRaHS |
| Wright 0.4 N | WY | 2.18 | CoCoRaHS |
| Hot Springs 0.4 NW | SD | 2.15 | CoCoRaHS |
| Hill City 4.4 SSW | SD | 2.13 | CoCoRaHS |
| Spearfish | SD | 2.12 | NWS Cooperative Observer |
| Rapid City 6.2 NNE | SD | 2.1 | CoCoRaHS |
| Lead 3.1 NNW | SD | 2.1 | CoCoRaHS |
| Rapid City 3.0 N | SD | 2.09 | CoCoRaHS |
| Edgemont | SD | 2.04 | NWS Cooperative Observer |
| Rozet 4.4 NNE | WY | 2.03 | CoCoRaHS |
| Edgemont 0.4 W | SD | 2.02 | CoCoRaHS |
| Newcastle 33 WSW | WY | 1.99 | CoCoRaHS |
| Wasta 21.6 SSW | SD | 1.96 | CoCoRaHS |
| Hot Springs 5.2 NW | SD | 1.95 | CoCoRaHS |
| Buffalo Gap 12.0 SE | SD | 1.93 | CoCoRaHS |
| Rapid City NWS | SD | 1.92 | ASOS |
| Sundance | WY | 1.88 | NWS Cooperative Observer |
| Weston 10.9 NE | WY | 1.86 | CoCoRaHS |
| Rapid City Airport | SD | 1.85 | ASOS |
| Edgemont 2.2 ENE | SD | 1.84 | CoCoRaHS |
| Lead | SD | 1.81 | NWS Cooperative Observer |
| Spearfish 0.1 WSW | SD | 1.8 | CoCoRaHS |
| Piedmont 1 NW | SD | 1.8 | NWS Cooperative Observer |
| Rapid City 8.4 W | SD | 1.78 | CoCoRaHS |
| Piedmont 4.6 E | SD | 1.76 | CoCoRaHS |
| Faith 20.5 NW | SD | 1.76 | CoCoRaHS |
| Rapid City 3.5 NE | SD | 1.69 | CoCoRaHS |
| Hot Springs 4.2 W | SD | 1.68 | CoCoRaHS |
| Custer 17.7 SSW | SD | 1.67 | CoCoRaHS |
| Gillette | SD | 1.65 | NWS Cooperative Observer |
| Spearfish 1.3 ESE | SD | 1.65 | CoCoRaHS |
| Hermosa 0.3 ENE | SD | 1.64 | CoCoRaHS |
| Moorcroft 15.0 ENE | WY | 1.62 | CoCoRaHS |
| New Underwood 3.9 S | SD | 1.6 | CoCoRaHS |
| Ft. Meade/Sturgis | SD | 1.59 | NWS Cooperative Observer |
| Oelrichs | SD | 1.58 | NWS Cooperative Observer |
| Gillette 9.7 ENE | WY | 1.58 | CoCoRaHS |
| Tilford 0.1 N | SD | 1.55 | CoCoRaHS |
| Rapid City 3.4 WNW | SD | 1.53 | CoCoRaHS |
| Gillette 0.6 NE | WY | 1.45 | CoCoRaHS |
| Belle Fourche 0.9 SSE | SD | 1.45 | CoCoRaHS |
| Rapid City 4 NW | SD | 1.42 | NWS Cooperative Observer |
| Gillette 0.5 ENE | WY | 1.41 | CoCoRaHS |
| Union Center 10.5 NW | SD | 1.4 | CoCoRaHS |
| Box Elder 1.6 NE | SD | 1.4 | CoCoRaHS |
| Upton 12.6 WNW | WY | 1.37 | CoCoRaHS |
| Gillette 2.8 SW | WY | 1.3 | CoCoRaHS |
| Hermosa 10.3 ESE | SD | 1.26 | CoCoRaHS |
| Buffalo Airport | SD | 1.21 | ASOS |
| Gillette Airport | WY | 1.15 | ASOS |
| Box Elder 6.2 ESE | SD | 1.15 | CoCoRaHS |
| Upton 1.0 NNW | WY | 1.09 | CoCoRaHS |
| Harding 3 SE | SD | 1.09 | NWS Cooperative Observer |
| Devils Tower 2.1 ESE | WY | 0.93 | CoCoRaHS |
| Wasta | SD | 0.87 | NWS Cooperative Observer |
| Sundance 1.0 ENE | WY | 0.78 | CoCoRaHS |
| Faith Airport | SD | 0.77 | ASOS |
| Bison 8.7 W | SD | 0.71 | CoCoRaHS |
| Newell 6.5 ENE | SD | 0.69 | CoCoRaHS |
| Bison 24.1 SW | SD | 0.69 | CoCoRaHS |
| Box Elder 8.0 NNE | SD | 0.68 | CoCoRaHS |
| Sundance 4.4 E | WY | 0.61 | CoCoRaHS |
| Sundance 7.0 SSE | WY | 0.6 | CoCoRaHS |
| Faith 36.3 W | SD | 0.57 | CoCoRaHS |
| Philip Airport | SD | 0.53 | ASOS |
| Newell 2.8 ENE | SD | 0.51 | CoCoRaHS |
| Kyle 2 E | SD | 0.51 | NWS Cooperative Observer |
| Hulett 0.4 SSE | WY | 0.47 | CoCoRaHS |
| Olsonville 4.5 SE | SD | 0.42 | CoCoRaHS |
| Red Owl | SD | 0.4 | NWS Cooperative Observer |
| Opal | SD | 0.4 | NWS Cooperative Observer |
| Mission 14 S | SD | 0.39 | NWS Cooperative Observer |
| Carlile 6.7 ENE | WY | 0.32 | CoCoRaHS |
| Winner Airport | SD | 0.25 | ASOS |
| Lodgepole 5 SW | SD | 0.25 | NWS Cooperative Observer |
| Pine Ridge Airport | SD | 0.16 | ASOS |
| Hamill 1.7 SW | SD | 0.13 | CoCoRaHS |
| White River 12.7 ENE | SD | 0.1 | CoCoRaHS |
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