Multi-instrumental observation of ionospheric responses to two weak magnetic storms occurred during the period, 18-21 March 2002, was conducted using GPS network, MU radar, and ionosondes, over the mid-latitude sector, and compared with the output generated by FLIP model. Latitudinal and temporal variations of GPS-TEC exhibit poleward expansion up to 35 degrees N, during day time hours (around 1000-1300 JST), of 19 and 21 March after the SSCs. It is interesting to note that, although the second storm considered here is very weak, on 20 March after the SSC around mid-night, MU radar observed that neutral wind increases rapidly up to 200 m/s, towards equator and simultaneously, a perturbation component of about 2 TECU is observed by GPS network, around 0100 JST of 21 March, which propagate from north to equator. lonosondes also revealed that, after the second SSC, around 0200 JST on 21 March, F-layer height increases at Wakkanai, and Kokubunji which propagates to Okinawa, exhibiting a latitudinal dispersion feature, showing the influence of equatorward neutral wind/propagating nature of a powerful wind surge. The equivalent neutral wind derived from FLIP model by including vibrationally excited nitrogen, N-2* and without its inclusion are almost identical and in good agreement with the MU radar neutral wind. The interplanetary-magnetosphere scenario of the initial and main phase of the two weak geomagnetic storms considered in the present study are quite different, which is reflected in the ionospheric responses to these events. (C) 2011 Elsevier Ltd. All rights reserved.