After Sukkos, we immediately begin saying mashiv haruach, as it is the rainy season. However, we delay saying v'sein tal umattar, the request for rain, until we have given the pilgrims who came to Jerusalem for the festival time to get home (Taanis 10a). We don't want them to get rained on on the way.
We continue saying v'sein tal umattar until erev Pesach (Shulchan Aruch O.C. 117:1).
How come we don't stop a few days early, to give the pilgrims a dry journey to Jerusalem? How come we only want to facilitate a dry journey home? If anything, I would have thought the opposite - we should want to ensure a dry journey to Jerusalem, lest someone refrain from coming due to the treacherous journey.