▁weather ▁systems ▁to ▁react ▁with ▁it ▁to ▁create ▁much ▁precip itation , ▁as ▁happens ▁more ▁frequently ▁to ▁the ▁north ▁and ▁east ▁of ▁the ▁area ; ▁some ▁exceptions ▁occur ▁during ▁some ▁aut umn ▁( t rop ical ▁weather ▁systems ) ▁and ▁spring ▁( st alled ▁front s ▁to ▁the ▁north ). ▁ ▁During ▁the ▁spring ▁season , ▁as ▁well ▁occasionally ▁during ▁the ▁fall ▁season , ▁severe ▁th under st orm s ▁often ▁build ▁on ▁the ▁Ser ran ias ▁Del ▁Bur ro ▁to ▁the ▁distant ▁west ▁of ▁Del ▁Rio . ▁ ▁This ▁is ▁believed ▁to ▁occur ▁due ▁to ▁the ▁u pl ift ▁of ▁mo ist ure ▁from ▁the ▁G ulf ▁of ▁Mexico ▁which ▁is ▁ch anne led ▁along ▁the ▁Rio ▁Grande ▁River . ▁ ▁In ▁the ▁event ▁of ▁an ▁strong ▁mid - to - upper ▁tro pos phere ▁tr ough ▁position ed ▁over ▁the ▁Des ert ▁South west , ▁these ▁severe ▁th under st orm s ▁can ▁migr ate ▁off ▁the ▁higher ▁terrain ▁of ▁the ▁mountains ▁and ▁across ▁the ▁Rio ▁Grande ▁into ▁the ▁Ciudad ▁A cu ña ▁and ▁Del ▁Rio ▁area ▁and ▁cause ▁significant ▁damage ▁when ▁they ▁impact ▁populated ▁areas . ▁One ▁of ▁these ▁storm s ▁caused ▁several ▁death s ▁in ▁Ciudad ▁A cu ña ▁on ▁May ▁ 2 5 , ▁ 2 0 1 5 , ▁when ▁a ▁torn ado ▁destroyed ▁several ▁structures ▁in ▁the ▁town . ▁ ▁Del ▁Rio ▁itself ▁was ▁largely ▁sp ared , ▁but ▁saw ▁a ▁massive ▁ha ilst orm ▁the ▁following ▁year ▁on ▁February ▁ 2 2 , ▁ 2