La Nina Peaks in January; El Nino risk late 2022.

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Fig. 1: Climate Impact Company ENSO phase probability forecast for 2022.

Executive summary: The monthly Climate Impact Company ENSO Outlook for 2022 indicates ongoing La Nina will peak in January, steadily weaken by quarter 2 of 2022 shifting into neutral phase and possibly trend toward El Nino late this year (Fig. 1). Forecast confidence is above average that La Nina will not continue (or weaken and then return) in 2022. Forecast confidence shifts from low to below average on prospects of El Nino later in 2022. As a reminder, the DEC/JAN/FEB climate patterns associated with La Nina feature dry-to-drought climate across the southern U.S., chilly/snowy weather in Southwest Canada, wet climate in the Ohio Valley and a wet regime for northern Brazil and Indonesia (Fig. 2). The pattern described reverse if El Nino develops by next DEC/JAN/FEB (Fig. 3).

Fig. 2: NOAA/CPC primary global climate impacts of La Nina in DEC/JAN/FEB.

Fig. 3: NOAA/CPC primary global climate impacts of El Nino in DEC/JAN/FEB.

Discussion: The Climate Impact Company Nino34 SSTA analog forecast reveals the ongoing double La Nina regime, the second of which peaks in January (Fig. 4). Neutral ENSO follows and analogs strongly suggest El Nino later in 2022. There is a tendency for the Pacific decadal oscillation (PDO) to run parallel with ENSO. The PDO identifies the North Pacific SSTA regime. The Climate Impact Company PDO analog forecast indicates cool phase PDO weakens but remains in 2022 (Fig. 5). If so, the El Nino risk is lower and/or delayed.

Fig. 4: Climate Impact Company Nino34 SSTA analog forecast for 2022.

Fig. 5: Climate Impact Company PDO analog forecast for 2022.

The modern-day climate pattern indicates the Pacific and Atlantic SSTA (and resulting atmospheric flow patterns) are more connected. There is a tendency the past 1-2 decades for regions of anomalous warm or cool away from the tropics to develop and create dramatic impacts on regional climate. The ENSO pattern certainly has a relationship with PDO. However, the PDO has a relationship with the Atlantic multidecadal oscillation (AMO), a climate index identifying the North Atlantic SSTA regime.

Fig. 6: Climate Impact Company AMO analog forecast for 2022.

Fig. 7: PDO/AMO warm season U.S. drought risk and likely 2022 scenario.

The AMO is unusually warm for late in the year. The Climate Impact Company AMO analog forecast reveals the warm signature should fade through Q1 of 2022 and remain steady near weak warm phase for 2022 (Fig. 6). Dynamic models are warmer and preferred is the warmest analog for the 2022 forecast. Consequently, during the 2022 warm season a -PDO/+AMO climate is projected which favors increased U.S. drought risk for the Southwest U.S., West-central U.S., Midwest/Upper Midwest States and the Southeast region (Fig. 7).

Globally, many zones are currently tracked as to their impacts on regional and global climate. Of course, La Nina is vividly indicated in the equatorial East Pacific (Fig. 8). The -PDO regime attached to La Nina is also indicated in both hemispheres. However, other regions of influence (mostly “warm blobs” of SSTA) are also present. The most famous “warm blob” born in 2013-14 in the Northeast Pacific has shifted west toward and just east of the Dateline. A slow eastward push of this warm zone is expected over the next several months which would weaken the -PDO regime. The North Atlantic warm SSTA is unusual for this late in the year and is expected to continue – likely stronger than revealed by the analog forecast. The +AMO regime is biasing the eastern North America winter climate warm!

Fig. 8: Current global SSTA and regions of importance.

In the southern hemisphere many regional SSTA patterns of importance are followed. The previously record warm tropical South Atlantic (TSA) index is now fading. This SSTA regime lead to a wet spring in Brazil. That wet influence should begin to ease. “Warm blobs” are evident in the South Indian Ocean, near and east of New Zealand and east of Argentina. Each “warm blob” is well-correlated with high-pressure ridging in the upper atmosphere helping to shape the upcoming summer climate pattern in the southern hemisphere.

Conclusion: La Nina 2021-22 peaks in January and fades to neutral phase during Q2/2022. El Nino risk is indicated for late 2022. The PDO regime which tends to run parallel to ENSO stays in the cool phase but is weaker for much of 2022. The North Atlantic warmth is likely to continue and be stronger than indicated by the analog forecast. The warm North Atlantic increases the risk of a warm winter in eastern North America, another busy tropical cyclone season in 2022 and combined with -PDO creates widespread U.S. drought risk. Southern hemisphere summer is heavily influenced by La Nina. However, regional influence by several “warm blobs” is also likely.