Weidenaar shot 5 for 6 from behind the arc.
Eddy Kayouloud had 18 points and eight rebounds for Central Arkansas (3-9, 2-0 Southland Conference). Rylan Bergersen added 15 points and six rebounds. Hayden Koval had 10 points and five blocks for the home team.
Central Arkansas has won two straight after starting the season 1-9.
The Islanders were up 40-29 at the break. Central Arkansas gradually chipped away at the lead until a Bergersen jumper at the 1:49 mark gave the Bears the lead for good 67-65.
Myles Smith scored a career-high 31 points and had seven rebounds for the Islanders (4-8, 0-2). Jashawn Talton-Thomas added six rebounds and six assists.
Central Arkansas plays Marquette on the road next Saturday. Texas A&M-Corpus Christi plays Nebraska on the road next Sunday.
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Elements of this story were generated by Automated Insights, http://www.automatedinsights.com/ap, using data from STATS LLC, https://www.stats.com