Interestingly the strong El Ni ños of 66 had very cold winter temperatures relative to normal for the Carolinas. Averaging the previous six strong El Ni ños, we find only a small deviation from normal in either winter mean temperatures or coldest winter temperatures for North or South Carolina. This tendency for cool winter temperatures becomes much weaker across the Carolinas. warm winter temperatures.ĭuring strong El Ni ños there is a tendency for winter temperatures to run below normal for the southernmost United States from southern California eastward across the Gulf Coast states. Observed Winter Precipitation (Dec-Feb) during strong El Ni ños P owerful subtropical jet streams (frequently observed during El Nino winters) efficiently transport this moisture across the southern United States where it falls as rain - or occasionally snow! What produces this heavy rain? Huge thunderstorm clusters over the unusually-warm tropical eastern Pacific Ocean lift tremendous amounts of moisture into the atmosphere. Above-normal precipitation typically extends across much of the Southeastern United States and also along the west coast during El Ni ño winters. Precipitation anomalies were largest near the coast the southern coastal plain of North Carolina averaged 3.04" above normal while the northern coastal plain of South Carolina averaged 3.37" above normal. Over the three winter months (December through February) rainfall was consistently above normal across all of the Carolinas. This map shows the observed winter precipitation anomalies averaged across the last six strong El Ni ño events. Huske Lock and Dam, on the Little Pee Dee River at Gallivant's Ferry, and on the Black River at Kingstree, SC during El Ni ño winters. Some of the highest river crests ever observed occurred on the Cape Fear River at William O. During the winters of 98 extremely large amounts of rain fell causing long periods of river flooding across the eastern Carolinas. In almost all cases a strong El Ni ño brings above-normal rainfall to the Carolinas during the winter months of December through February. This exacerbated river flooding problems across the coastal plain of both Carolinas.Įl Ni ño should bring lots of rain to the Carolinas. Courtesy NWS Burlington, VT.Īnother wet storm that brought 1 to 3 inches of rainfall to the eastern Carolinas on January 23, 1998. It also produced a devastating ice storm over parts of New England and southeastern Canada. Strong storm system January 6-8, 1998 that brought 1-2 inches of rain to the eastern Carolinas. Similar storm systems should be a common occurrence during this upcoming winter. The second storm (January 23, 1998) dumped another 1 to 3 inches of rain across the eastern Carolinas. The first (January 6-8, 1998) brought 1-2 inches of rain to eastern North and South Carolina. Both of these systems developed within an active subtropical jet stream and brought substantial rainfall to the southeastern United States. Here are satellite loops from two low pressure systems that developed during the strong El Ni ño winter of 1997-1998. Looking back over the past 60 years there have been six strong El Ni ño events we can use to base a winter outlook on. This particular El Ni ño is expected to become strong this winter, perhaps rivaling some of the strongest events in recent history. These alternate at irregular intervals of 1 to 4 years. ENSO has two phases: a warm phase we call El Ni ño and a cool phase called La Ni ña. However its largest local impacts are noted during the winter with heavier precipitation typically occurring across the southern United States including the Carolinas.Įl Ni ño is actually just one phase of the El Ni ño/Southern Oscillation, often called by the acronym ENSO. El Niño typically reduces the severity of our hurricane season due to increased wind shear across the tropical Atlantic and Caribbean. ![]() Although El Ni ño is a warming of the tropical eastern Pacific Ocean and the overlying atmosphere, it has global weather impacts with changes in temperature and precipitation patterns across the planet. El Ni ño is expected to continue through this upcoming winter and into the spring of 2016.
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