Hysell, D. L.Kirchman, A.Harding, B. J.Heelis, R. A.England, Scott L.2023-07-312023-07-312023-05e2023SW003427http://hdl.handle.net/10919/115952Measurements from the Ionospheric Connections Explorer satellite (ICON) form the basis of direct numerical forecast simulations of plasma convective instability in the postsunset equatorial F region ionosphere. ICON data are selected and used to initialize and force the simulations and then to test the results one orbit later when the satellite revisits the same longitude. Data from the IVM plasma density and drifts instrument and the MIGHTI red-line thermospheric winds instrument are used to force the simulation. Data from IVM are also used to test for irregularities (electrically polarized plasma depletions). Fourteen datasets from late March 2022, were examined. The simulations correctly predicted the occurrence or non-occurrence of irregularities 12 times while producing one false positive and one false negative. This demonstrates that the important telltales of instability are present in the ICON state variables and that the important mechanisms for irregularity formation are captured by the simulation code. Possible refinements to the forecast strategy are discussed.application/pdfenCreative Commons Attribution 4.0 InternationalICONequatorial spread Fionospherespace weatherforecastingArticle - Refereedhttps://doi.org/10.1029/2023SW0034272151542-7390