The solar flare effect (SFE) at dip equatorial latitudes sometimes shows the counter-Sq variation around local noon. In this paper, we refer to this type of SFE as SFE*. Observations obtained by the Circum-pan Pacific Magnetometer Network (CPMN) reveal some previously unknown characteristics of SFE*. Some of these features are the following: (1) the counter-Sq SFE variation is observed in limited longitude (local time) and latitude sectors (i.e., LT ≈ 1030-1300, \DipLat.\ ≲, 1.5°) (2) outside this limited region, the amplitude of SFE(Z/) and preflare S q(H) have a linear relationship (3) SFE* is observed during the significant depression of the horizontal magnetic field at dip equatorial latitudes, which indicates the presence of westward electric fields whose origin remains to be understood.
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