The U.S. Climate Prediction Center (CPC) canceled the El Niño Watch in early November in response to a recent decline in water temperatures in the tropical Pacific Ocean.
The CPC also noted the atmospheric circulation patterns associated with El Niño failed to develop.
The oscillation of ocean temperatures and atmospheric circulation in the tropical Pacific
Ocean is referred to as the El Niño Southern Oscillation (ENSO).
An El Niño condition is declared when ocean temperatures in this region are warmer than normal and atmospheric circulation is altered (weakening of trade winds).
The CPC now expects ENSO neutral conditions to prevail for the winter. Neutral conditions occur when ocean temperatures and circulation patterns approach normal levels.
In contrast to El Niño years when winters are often wet, precipitation during neutral winters trends closer to normal.
The CPC long range forecasts for December through February now reflect this updated status regarding ENSO.
Precipitation for December through February now falls in the equal chances category which means the probability of below normal, normal, and above normal precipitation is approximately equal.
Temperature forecasts for the winter now exhibit a moderate warm bias for central Arizona.