According to NOAA (the federal agency focused on the condition of the oceans and the atmosphere) La Niña conditions have returned! In NOAA’s latest winter weather prediction they tell us that, “SINCE THE LAST SEASONAL OUTLOOK, LA NINA CONDITIONS HAVE RETURNED. THIS IS INDICATED BY A STRENGTHENING OF NEGATIVE SEA SURFACE TEMPERATURES ACROSS THE EASTERN HALF OF THE EQUATORIAL PACIFIC AND AN INCREASE IN BELOW-AVERAGE SUBSURFACE OCEAN TEMPERATURE ANOMALIES IN THE EASTERN PACIFIC, COUPLED WITH THE FACT THAT THE ATMOSPHERIC CIRCULATION ACROSS THE PACIFIC ALSO CONTINUES TO EXHIBIT CHARACTERISTICS OF LA NINA. IMPACTS ASSOCIATED WITH LA NINA ARE NOW INDICATED DURING THE AUTUMN, WINTER AND SPRING MONTHS.”
Here is a look at NOAA’s winter precipitation prediction maps for the 2011 – 2012 winter.
How to read these weather prediction maps.
“The contours on the map show the total probability (%) of three categories, above, indicated by the letter “A”, below, indicated by the letter “B”, and the middle category, indicated by the letter “N”. At any point on the map, the sum of the probabilities of these three categories is 100%. For any particular location, and season, these three categories are defined from the 30 observations from 1981-2010. The coldest or driest 1/3 (10 years) define the B category, the warmest or wettest 1/3 (10 years) define the A category, and the remaining 10 years in between define the middle (N) category.”
Precipitation Probability for December, January, February.
Precipitation Probability for January, February, March.
Precipitation Probability for March, April, May.
THE MAIN FACTORS WHICH USUALLY INFLUENCE THE SEASONAL CLIMATE OUTLOOK INCLUDE: 1) EL NINO AND LA NINA 2) TRENDS 3) THE TROPICAL 30-60 DAY OSCILLATION (MJO) 4) THE NORTH ATLANTIC OSCILLATION (NAO) 5) THE PACIFIC DECADAL OSCILLATION (PDO) 6) PERSISTENTLY DRY OR WET SOILS IN THE SPRING AND SUMMER. 7) STATISTICAL FORECAST TOOLS - CANONICAL CORRELATION ANALYSIS (CCA), 8) DYNAMICAL FORECAST MODELS 9) CONSOLIDATION (CON)