INDIANAPOLIS (WISH) — Several weeks ago, the Climate Prediction Center issued their Winter Season Forecast.
The forecast calls for a greater chance of above normal temperatures and lower than average precipitation. The forecasts are made largely on the assumption of a strong El Nino.
The graphic below shows what a typical El Nino pattern looks like.
There are a few differences from this El Nino and the strong ones in 1982-1983 and 1997-1998, El Nino that could be important factors in central Indiana’s winter weather.
The recent change has been a persistent pool of warmer than normal water off the Baja Mexico Peninsula.
The second change is that the warm pool of water is shifting a bit to the west. Both of these could alter the Jet Stream pattern that steers upper level wind flow and temperature regimes.
Recent model data suggests that El Nino will weaken in time for the last part of winter. All of these could greatly alter the winter patterns.