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Space weather is driven by solar activities by pulling out the variety of phenomenon such as solar flare and coronal mass ejection (CMEs). It been discovered the CMEs and solar flares have causes disturbance at near-Earth space. This paper is to examined the behaviour of geomagnetic storm, horizontal geomagnetic field and several solar wind parameters during solar flare and CMEs event at minimum of solar cycle of 24. Observational result found that association of strongest solar flare and CMEs have declined the geomagnetic storm until -150nt at 8th September 2017. Following to this, the H component reading also slightly decreased at three magnetometer location respectively. Solar flare and CMEs released the energetic particles that could disturbed the radio communications at the Earth and electronic equipment. Therefore, it was required to study and understanding the solar flare and CMEs event.

The East coast of Peninsular Malaysia receives a strong wind speed, heavy rain and high humidity during the Northeast monsoon. The Malaysian Meteorological Department claims that the wind speed during the Northeast season could reach 55.56 km/h or more. This strong wind speed and heavy rain could contribute to the attenuation of radio signals. This paper investigated the relationship between wind speed (km/h) and radio signal strength, RSS (dBm). The statistical correlation was employed to identify the correlation value and strength between them. The wind speed and RSS were collected during wet and dry seasons at Kusza Observatory, while the Spectrum analyser was used for measuring RSS (dBm) and the weather station for wind speed (km/h). The result showed that the wet season has strong and significant correlation compared to the dry season. Frequencies of 382.5 MHz, 945 MHz and 2160 MHz with correlation values of r =-0.583;-0.631 and-0:514, respectively, showed strong, negative and significant correlations with wind speed in the wet season. As for the dry season, only a frequency of 382.5 MHz showed a strong, positive and significant correlation with r = 0.555, while small and medium for others. This finding is useful to a radio astronomer to help determine the best period for radio astronomy observation with the lowest interference considering the weather in the East Coast of Peninsular Malaysia. Besides, this finding benefits a spectrum of users involved in mobile telecommunication, wireless internet, radio TV transmission and satellite broadcasting.

Previous studies have reported that coronal mass ejections (CMEs) and solar flares lead to the development of huge storms and high-speed streams. Our aim in this paper is to investigate the response of the geomagnetic index SYM/H to the solar wind parameters, such as solar wind speed V, dynamic pressure P, input energy IE and the interplanetary magnetic field (IMF) Bz component, associated with solar flares and CME events. The response of the ground geomagnetic field (H-component) to the solar wind parameters and the IMF Bz component at three low-latitude stations has also been analysed. Our findings show that the delay of the solar wind changes in the Earth’s magnetosphere in response to the weak geomagnetic storm (SYM/H = −30 nT) at the beginning of 2014 December 21. A weak storm of SYM/H = −30 nT in the middle of 2014 November 5 is suggested by a low magnetic reconnection process in the magnetosphere. In addition, the strong southward IMF Bz component and high solar wind changes in the magnetosphere system, which were a result of the X2.0 solar flare event and the CMEs on 2014 October 27, responded to the moderate storm (SYM/H = −60 nT) at the beginning of 2014 October 28. This dynamic physical process in the magnetosphere caused by solar wind variation is seen to excite the Earth’s H-component through ultra low frequency at the ground-based magnetometers at the BCL (Vietnam), TIR (India) and SCN (Indonesia) stations during the geomagnetic storm. This study relates to seismic investigations and geomagnetic-induced current on the ground.