Database: bike_share_1
Question: For the rides that started at Market at 10th station and ended at South Van Ness at Market station in August of 2013, which day had the coldest temperature?
SQL: SELECT T1.start_date FROM trip AS T1 INNER JOIN weather AS T2 ON T2.zip_code = T1.zip_code AND T2.date = SUBSTR(CAST(T1.start_date AS TEXT), 1, INSTR(T1.start_date, ' ') - 1) WHERE T2.date LIKE '8/%/2013' AND T1.start_station_name = 'Market at 10th' AND T1.end_station_name = 'South Van Ness at Market' AND T2.min_temperature_f = ( SELECT MIN(T2.min_temperature_f) FROM trip AS T1 INNER JOIN weather AS T2 ON T2.zip_code = T1.zip_code AND T2.date = SUBSTR(CAST(T1.start_date AS TEXT), 1, INSTR(T1.start_date, ' ') - 1) WHERE T2.date LIKE '8/%/2013' AND T1.start_station_name = 'Market at 10th' AND T1.end_station_name = 'South Van Ness at Market' )