A storm ravaging the northwestern district of Mexico sparked an impressive tornado in the city of San Pedro.Footage shared online from the National Weather Commission (Conagua) shows the tornado forming close to a trafficked street of the Sinaloa town.Onlookers can be seen curiously watching the funnel of swirling air sucking up more warm air from the ground to strengthen its walls.Local authorities said the tornado began to form at around 7pm on…