@echo off
set localdir=C:something
set ftphost=your.ftp.host.com
set ftpuser=yourftpuser
set ftppass=yourftppassword
set ftpdir=target/directory/on/server
setlocal enableDelayedExpansion
for /F %%x in ('dir /B/D %localdir%') do (
set FILENAME=%localdir%\%%x
curl -T !FILENAME! ftp://%ftphost%/%ftpdir%/ --user %ftpuser%:%ftppass%
)