DAYTON, Ohio (WDTN)- The Miami Valley expects a strong El Nino pattern this winter. The last time a strong El Nino had an influence on our winter was the 2015-16 season, resulting in a drier-than-normal winter with just 12.7 inches of snow.
The average date for our first snowfall is Nov. 24, but this winter we are expecting a strong El Nino to be in play, which historically means lower precipitation and warmer than average days, but that does not mean that we won’t see snow or cold temperatures.
Oct. 18, 1989, was the earliest that Dayton had ever seen measurable snow, amounting to 0.2 inches of snow. With a forecast high in the 60s Wednesday, we shouldn’t see snowfall quite that early this year.
“We’re expecting a large variation in temperature,” John Franks, National Weather Service Wilmington incident meteorologist, “so the high and low peaks. But averaging more on the warm side.”
El Nino is marked by above-normal sea surface temperatures in the central and eastern tropical Pacific Ocean, which has been the case since spring. The pattern generally results in the polar jet residing to the north of Ohio, but variabilities in how far south the polar jet resides can bring in heavy amounts of snow at times.
“Sometimes you get that really cold air come in and ahead of that trough, you’ve got warm air from the Gulf,” said Franks. “And if it’s established like that, the intersection where those come through really create larger snowfall events.”
While El Nino has a pattern of behaving the same way historically, not all of the characteristics of an El Nino winter will be felt 100% of the time. The Climate Prediction Center forecasts that there is an 80% probability that El Nino will continue through Spring. You can find more information and products about El Nino and its impact by going to the NOAA website and Climate.gov.