The figure above indicates the forecasted high in orange (with error bar denoting the range of ensemble forecast members), average high for this time of year in orange (dashed line), forecasted low in blue (with error bar), average low this time of year in blue (dashed line), and forecasted wind speed in purple. Note that the wind speed forecast is sustained wind (not gusts), and it is based on only one model (not an ensemble).
The tail end of a cold front will move across Arizona tomorrow evening – Wednesday morning. We will see breezy southwest winds and at least partly cloudy skies tomorrow in advance of the front. Then, after frontal passage the skies will clear, winds will die down and shift to a northwesterly direction as temperatures become cooler Wednesday to Thursday morning. Low temperatures by Thursday morning should be in the lower 20s. Precipitation is unlikely with this cold front.
A ridge of high pressure will then rebuild over the Southwest, bringing warmer-than-normal conditions by Friday and through the coming weekend.
Some people have inquired about the outlook for this winter and whether or not we will have a white Christmas. Some less reputable weather forecast companies such as AccuWeather will provide detailed long-range weather forecasts up to 3 months in advance (including Christmas Day), but they should not receive any credibility beyond about 10 days. Numerical weather forecast models enable meteorologists to achieve at least a low degree of forecast accuracy out to 10 days. Beyond that time, long-range forecasts provided by the NOAA Climate Prediction Center (www.cpc.noaa.gov) are statistical probabilities of mean temperatures and precipitation amounts being above or below the climatological norm. These predictions are primarily based on climate correlations sea surface temperature patterns. Since we are in a La Niña pattern, it is anticipated that this winter will likely be warmer and drier than normal here in Arizona and throughout much of the southern US. The drought conditions in southern California, southern Arizona, and much of the southern half of the country are expected to persist or even intensify this winter through next spring.
Met Mail is an unofficial weather discussion and forecast transmitted once or twice a week via e-mail by the Embry-Riddle Department of Meteorology (http://meteo.pr.erau.edu/). Embry-Riddle offers an undergraduate bachelor-of-science degree program in Applied Meteorology. Please spread the word to all potential qualified candidates!
ERAU Applied Meteorology degree program
Official National Weather Service forecast