Seasonal Climate Forecast Dec. 2021 –Feb. 2022

[Pages:24]Seasonal Climate Forecast October ? December 2023

Issued: September 21, 2023

Contact: ODF Lead Meteorologist Pete Parsons 503-945-7448 or peter.gj.parsons@odf.

ODA production support: Diana Walker; Andy Zimmerman; Jenn Ambrose ODF production support: Julie Vondrachek; Kristin Cody

El Ni?o vs La Ni?a

(SST Patterns in the Tropical Pacific Ocean)

Courtesy:

Sea Surface Temperatures (SSTs)

Animated (PowerPoint only) SSTs (top) / Anomalies (bottom)

El Ni?o is strengthening

Courtesy:

El Ni?o Southern Oscillation (ENSO) Current Status and Forecast

n The monthly Southern Oscillation Index (SOI) fell from -0.3 to -0.8, reflecting weakening easterly trade winds across the tropical Pacific Ocean and a strengthening El Ni?o.

n The June ? August 2023 Oceanic Ni?o Index (ONI +1.1?C) warmed into the moderate El Ni?o range. This index lags real-time sea surface temperatures (SSTs), which reflect moderate-strong El Ni?o conditions.

n NOAA's Climate Prediction Center (CPC) has issued an El Ni?o Advisory. Their dynamic modeling average predicts a strong El Ni?o (ONI > 1.5?C) by this winter.

Important Note: This "Seasonal Climate Forecast" does not consider NOAA's ENSO forecast. It uses only historical and current ENSO conditions to find "analog years" that most-closely match the evolution of the current ENSO state.



Southern Oscillation Index (SOI)

(1950-1951; 1964-1965; 1971-1972) La Ni?a

Aug. 2023 SOI (-0.8) dropped into El Ni?o

territory

ENSO-Neutral

El Ni?o

Aug. analogs ranged from ENSO-neutral to El Ni?o

Oceanic Ni?o Index (ONI)

(1950-1951; 1964-1965; 1971-1972)

Strong El Ni?o

Moderate Weak

ENSO-Neutral

Weak Moderate

Strong La Ni?a

Jun. ? Aug. 2023 ONI (+1.1?C) reflected moderate El Ni?o

Jun. ? Aug. ONI analogs were in weak or moderate

El Ni?o

The Pacific Decadal Oscillation (PDO)

(Reflects SST "Phase" in the North Pacific Ocean )

Positive (Warm) "Phase"

Negative (Cool) "Phase"

SST Anomalies

Courtesy:

North Pacific Ocean

(Poleward of 20?N Latitude)

(1950-1951; 1964-1965; 1971-1972) Warm Phase

Neutral

Jan. 2022 PDO not available

Aug. 2023 PDO (-2.47)

remained deeply in "Cool Phase"

Cool Phase

Aug. analog PDO values were in the "Neutral" or "Cool Phase"

 ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download