Reinette LeJeune

The El Niño – Southern Oscillation (ENSO) update from the Climate Protection Center and the Columbia School points towards a higher probability of a third winter in a row of La Niña, increasing the odds given by previous forecasts. A month ago, projections estimated that the odds of La Niña continuing through winter (December-February) were at 65 percent, but now, forecasts are saying the odds have increased to 75 percent. 

So what does this mean for Pennsylvanians? As meteorologists have pointed out over the last year, La Niña conditions typically lead to wetter conditions west of the state, drier conditions south of the state, and mixed conditions for the state itself. La Niña winter weather in Pennsylvania is more difficult to predict than the El Niño winter weather (El Niño usually means noreasters and big storms). La Niña winters in the past have seen slightly above-average snowfall and near-average to above-average temperatures.

When can we expect La Niña to end this year? At present, meteorologists predict that La Niña will end during the February-April period, with an ENSO neutral pattern expected to still take over. Despite this, however, the odds of La Niña continuing into at least a portion of the spring season have increased. The ENSO forecast has been broken up into overlapping three-month periods:

• The odds of La Niña continuing into January-March are now up to 58 percent (up from 53 percent a month ago).
• The odds of a La Niña February-April are now up to around 44 percent (up from 38 percent a month ago).
• The odds of a La Niña spring, March-May are now up to 26 percent (up from 22 percent a month ago).

The National Oceanic and Atmospheric Administration is expected to release its winter 2022-2023 outlook in the coming weeks.