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Abstract We report an extraordinary L‐band scintillation event detected in the American sector on the night of 23–24 March 2023. The event was detected using observations distributed from the magnetic equator to mid latitudes. The observations were made by ionospheric scintillation and total electron content (TEC) monitors deployed at the Jicamarca Radio Observatory (JRO, ∼−1° dip latitude), at the Costa Rica Institute of Technology (CRT, ∼20° dip latitude), and at The University of Texas at Dallas (UTD, ∼42° dip latitude). The observations show intense pre‐ and post‐midnight scintillations at JRO, a magnetic equatorial site where L‐band scintillation is typically weak and limited to pre‐midnight hours. The observations also show long‐lasting extremely intense L‐band scintillations detected by the CRT monitor. Additionally, the rare occurrence of intense mid‐latitude scintillation was detected by the UTD monitor around local midnight. Understanding of the ionospheric conditions leading to scintillation was assisted by TEC and rate of change of TEC index (ROTI) maps. The maps showed that the observed scintillation event was caused by equatorial plasma bubble (EPB)‐like ionospheric depletions reaching mid latitudes. TEC maps also showed the occurrence of an enhanced equatorial ionization anomaly throughout the night indicating the action of disturbance electric fields and creating conditions that favor the occurrence of severe scintillation. Additionally, the ROTI maps confirm the occurrence of pre‐ and post‐midnight EPBs that can explain the long duration of low latitude scintillation. The observations describe the spatio‐temporal variation and quantify the severity of the scintillation impact of EPB‐like disturbances reaching mid latitudes. 

Abstract An all‐sky imager at El Leoncito Observatory (−31.8°, 69.3°W, 18.2° magnetic latitude) is used to study 630.0‐nm airglow emissions related to medium‐scale traveling ionospheric disturbances (MSTIDs). On the night of 6 December 2007 an unusual event consisting of bright bands propagating northwestward was observed. Enhancements in total electron content from ground‐based Global Positioning System receivers were observed collocated with the bright airglow bands. A regional Global Positioning System‐derived total electron content map matches the direction of motion, scale size, and location of these bright bands. Model results includingFregion coupling withEregion structures reproduce the characteristics of the bright bands. Specific conditions in theEregion must exist in order to observe these unusual MSTIDs consisting of propagating bright bands only.