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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 We analyze daytime quiet‐time MSTIDs between 2013 and 2015 at the geomagnetic equatorial and low latitude regions of the Chilean and Argentinian Andes using keograms of detrended total electron content (dTEC). The MSTIDs had a higher occurrence rate at geomagnetic equatorial latitudes in the June solstice (winter) and spring (SON). The propagation directions changed with the season: summer (DJF) [southeast, south, southwest, and west], winter (JJA) [north and northeast], and equinoxes [north, northeast, south, southwest, and west]. In addition, the MSTIDs at low latitudes observed between 8:00 and 12:00 UT occur more often during the December solstice and propagate northwestward and northeastward. After 12:00 UT, they are mostly observed in the equinoxes and June solstice. Their predominant propagation directions depend on the season: summer (all directions with a preference for northeastward), autumn (MAM) [north and northeast], winter (north and northeast), and spring (north, northeast, and southwest). The MSTID propagation direction at different latitudes was explained by the location of the possible sources. Besides, we calculated MSTIDs parameters at geomagnetic low latitudes over the Andes Mountains and compared them with those estimated at the geomagnetic equatorial latitudes. We found that the former is smaller on average than the latter. Also, our observations validate recent model results obtained during geomagnetically quiet‐time as well as daytime MSTIDs during winter over the south of South America. These results suggest that secondary or high‐order gravity waves (GWs) from orographic forcing are the most likely source of these MSTIDs.