In this paper we present an analysis of meteorological effects influencing the counting rate of a standard cosmic ray NM-64 neutron monitor and bare neutron counters used during the latitude survey performed in 1996--1997 from Italy to Antarctica and back. In particular, we determine for the first time the influence of the Bernoulli effect on the evaluation of atmospheric mass and the effect of sea state strength on neutron counting rate, by using data recorded during the long period spent in the Antarctic region (vertical cutoff rigidity Rcp≤1 GV). Atmospheric absorption coefficients have been computed accurately for the Antarctic region, as well as at different cutoff rigidities by combining previous findings together with our determinations at Rcp≤1 GV and Rcp=6.2 GV. We also estimate the temperature effect on the NM-64 counting rate by using the sea level temperature during the expedition and the vertical distribution data of atmospheric temperature measured by satellites. Data corrections for all meteorological effects are discussed. ¿ 2000 American Geophysical Union