Show the sea level status recorded by the weather station of store no.19 on 2013/2/24.
store no.19 refers to store_nbr = 19; on 2013/2/24 refers to date = '2013-02-24'; sea level status refers to sealevel
SELECT T1.sealevel FROM weather AS T1 INNER JOIN relation AS T2 ON T1.station_nbr = T2.station_nbr WHERE T1.`date` = '2013-02-24' AND T2.store_nbr = 19