A broad area of showers and thunderstorms slid through the southern half of KELOLAND overnight and early this morning as a cool front passed through. Rainfall amounts were generally under a half inch, though there were a few spots in Tripp and Gregory county in south central South Dakota that picked up a little more – along with some 3” size hail. After the rainfall ended, skies cleared from west to east for cooler weather with significantly less humidity than we felt over the weekend.
Tonight skies will be mostly clear and it will be cool. Overnight lows will be in the upper 50s East River to the low 60s in the west.
Tomorrow will be a partly to mostly sunny day, with a light southerly breeze warming us a few degrees. Highs will be near normal East River, in the low to mid 80s. It will be warmer in the west, with the low 90s. With an area of low pressure in western South Dakota, there could be some afternoon and evening thunderstorms in central and NE South Dakota. Sioux Falls could have some nighttime thunder, though severe storms are not expected.
(For those at Sturgis, it looks like a week of dry and hot weather throughout the rally – little or no rainfall.)
Thunderstorms will move across KELOLAND on Wednesday, along with warmer temperatures and more humid air. Highs will be above-normal in the upper 80s East River and the low 90s in the west. Storms that form in central and northern South Dakota have a marginal risk of becoming severe.
Thursday will be partly to mostly sunny and humid, with highs in the upper 80s East River to the low 90s in the west, with more shower and thundershower potential, mainly in central and NE South Dakota.
Friday will bring more thunderstorms East River, while it will be mostly dry and hot in the west. Temperatures will remain above-normal, with humid air in place.
A cold front will move through the area Saturday morning, bringing some thunderstorm chances with it for central and eastern KELOLAND (western SD remaining dry). Sioux Falls is projected to get afternoon rainfall. Behind the front, Saturday will also be cooler and less humid. High will be in the mid 80s. Sunday will be mostly sunny and even cooler, a few degrees either side of 80. Temperatures will warm a few degrees with abundant sunshine again on Monday.
Long range forecast models warm us a few degrees for the middle of next week before cooling slightly for the following weekend (August 22-23).