RRR Pattern Continues to Shape Medium-range Forecast

Chart of the day: Where did the term “ridiculously resilient ridge” come from?

Discussion: Myself and my associate Dr. Olivia Kellner will address a large crowd of folks in-charge of where we’ll be planting our crops over the next several decades due to the influence of climate change. The results are good and bad. While Dr. Kellner presents on that subject, I’ll discuss the influence of the recent tendency for large areas of anomalous warm ocean water to form and influence our climate. One of those warm zones is in the Northeast Pacific (since 2013). The chart above identifies the warming of the atmosphere by this warm water zone causing a semi-permanent upper-level high-pressure ridge (red). The location of the ridge for each of the past 9 years is identified. Recently, the ridge shifted to Western Canada. The term “ridiculously resilient ridge” was coined by the University of Washington climate scientists where study of the warm water zone is underway. There are now government centers (in U.S. and New Zealand) that only study marine heat waves they have become so dominant.

Medium-range 6-10 Day Forecast Valid May 17-21, 2023 (24-hour change)

Discussion: RRR pattern over Western Canada amplifies and causes downstream East Canada trough to strengthen. Staying very warm in the Northwest U.S. to California and Western Canada while the North-central U.S. trend cooler.

Medium-range 11-15 Day Forecast Valid May 22-26, 2023 (24-hour change)

Discussion: MJO influence flattens the amplified upper trough SLIGHLY. The West remains warm and the East is temperate.

U.S. Medium-range Precipitation Forecast

Discussion: MJO influence approaching/passing the Dateline has a generally drier influence on U.S. climate. The Southwest has some rain but not excessive while surrounding areas are trending drier.

Days 16-20 Extended range Temperature Forecast valid May 27-31, 2023 (previous below)

Discussion: Warm pattern in the Northwest remains stagnant. The warming in the central Great Plains to Missouri is based on identification of dry soils and influence on climate. Note the warmer change in the Great Plains (which is correct). There is a wet weather risk in the southeast Great Plains.