The report below was written by Scott Borgioli, WeatherAg Chief Meteorologist on March 25, 2023 (next update approximately May 1, 2023)
La Nina/El Nino: La Nina has dissipated as previously forecast. “Neutral” conditions now exist in key parts of the Equatorial Pacific (“Neutral” meaning neither a La Nina or El Nino exist). High probabilities continue to be the case for El Nino conditions developing during the late summer and continuing through Winter 2023-24. El Nino will likely then start to wane late winter or early Spring 2024 (preliminary). El Nino is currently predicted to be at a “weak” strength (almost all data signals this). Historically, of the 11 “weak” El Nino events since 1950, odds favor at least 80% of normal precipitation for the valley next water year with a much lessor chance of 51-79% (probabilistic, not exact). Regarding temperatures, weak El Nino events generally don’t tilt the pendulum one way or the other October through April.
- April, probabilistic odds and data favor below normal temperatures continuing. Through around April 10, mean temps as a whole look to be -10 to -5 of normal. April 11-30, mean temps are then predicted to be -7 to -2 of normal.
- April precipitation is predicted to be near to slightly above.
- May, probabilistic odds and data favor near normal temperatures. Except for a small swing towards slightly below normal temps May 1-8, there are no strong signals for the pendulum swinging one way or the other. Thus, mean temperatures as a whole for the month are favored at -3 to +3 of normal.
- May precipitation also looks to be near normal, with no signals towards wet or dry.
- June, probabilistic odds and data favor near normal temperatures (-2 to +4 of normal mean). Near normal precipitation is favored.
- As you would expect, odds strongly favor above normal mean temperatures for this entire period. This is too far out to have specific data to establish a predicted range for the expected above normal mean temperatures.
*Note that this outlook is preliminary. It is a generalized prediction based on the currently observed and anticipated weather patterns, model data, long term predictions, and historical trends. This outlook should not be used as a specific forecast, but rather as a tool of future probabilities based on current data signals and expert opinion.
We would like to thank all our sponsors for making this year’s Weather Watch Program possible. Weather Watch will begin again on November 15, 2023.
Articles are property of CCM; please seek permission from CCM for the use of articles and content in any way.