Weather patterns in the United States are usually different than during El NiÃ o years . La NiÃ a , sometimes informally called `` anti-El NiÃ o '' , is the opposite of El NiÃ o , where the latter corresponds instead to a higher sea surface temperature by a deviation of at least 0.5 Â C , and its effects are often the reverse of those of El NiÃ o. El NiÃ o is famous due to its potentially catastrophic impact on the weather along both the Chilean , Peruvian and Australian coasts , among others .