Home » September 2012 Southwest Climate Outlook » Temperature Outlook
Forecasts
Published September 26, 2012

Temperature Outlook

 (October 2012–March 2013)
Data Source(s): NOAA-Climate Prediction Center (CPC)

The seasonal temperature outlooks issued by the NOAA-Climate Prediction Center (NOAA-CPC) in September call for slightly increased chances that temperatures will be similar to the warmest 10 years in the 1981–2010 period for the October–December and November–January seasons (Figures 9a–b). Recent warming trends during these periods influence the forecasts. In the three-month seasons that follow, forecasts call for equal chances for above-, below-, or near-average conditions in Arizona and New Mexico (Figures 9c–d). Contributing to these forecasts is the uncertainty surrounding whether an El Niño event will form and what its ultimate strength will be. This affects  temperature because El Niño events often deliver increased precipitation in the Southwest that also, consequently, brings cooler temperatures. While forecasts currently indicate the formation of an El Niño event, confidence in the fate of the event should grow in coming months.
 

Seasonal Temperature Forcasts for the U.S.
Notes:

These outlooks predict the likelihood (chance) of above-average, average, and below-average temperature, but not the magnitude of such variation. The numbers on the maps do not refer to degrees of temperature.

The NOAA-CPC outlooks are a 3-category forecast. As a starting point, the 1981–2010 climate record is divided into 3 categories, each with a 33.3 percent chance of occurring (i.e., equal chances, EC). The forecast indicates the likelihood of one of the extremes—above-average (A) or below-average (B)—with a corresponding adjustment to the other extreme category; the “average” category is preserved at 33.3 likelihood, unless the forecast is very strong.

Thus, using the NOAA-CPC temperature outlook, areas with light brown shading display a 33.3–39.9 percent chance of above-average, a 33.3 percent chance of average, and a 26.7–33.3 percent chance of below-average temperature. A shade darker brown indicates a 40.0–50.0 percent chance of above-average, a 33.3 percent chance of average, and a 16.7–26.6 percent chance of below-average temperature, and so on.

Equal Chances (EC) indicates areas where no forecast skill has been demonstrated or there is no clear climate signal; areas labeled EC suggest an equal likelihood of above-average, average, and below-average conditions, as a “default option” when forecast skill is poor.

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