Prognostic Discussion for Long-Lead Seasonal Outlooks NWS Climate Prediction Center College Park MD 830 AM EST Thu Jan 20 2022 SUMMARY OF THE OUTLOOK FOR NON-TECHNICAL USERS The February-March-April (FMA) 2022 temperature outlook favors above-normal seasonal mean temperatures from the Southwest, across the Central and Southern Plains, to the entire eastern third of the contiguous U.S. The largest probabilities (above 60 percent) for above-normal temperatures are forecast across the Rio Grande Valley. Probabilities of below-normal temperatures are elevated for parts of the northern Rockies, Pacific Northwest, northern California, and much of Alaska. The FMA 2022 precipitation outlook favors below-normal seasonal precipitation amounts from southern California and the Southwest to the central and southern Great Plains, then east to parts of the Southeast. Below-normal precipitation is slightly favored for most of coastal southern Mainland Alaska and the Alaska Panhandle. Above-normal seasonal precipitation amounts are most likely across the Great Lakes, Ohio and Tennessee Valleys, northern Rockies, Pacific Northwest, and much of northern and western Mainland Alaska. Equal chances (EC) are forecast among areas where seasonal mean temperatures and seasonal accumulated precipitation amounts are expected to be similar to climatological probabilities. BASIS AND SUMMARY OF THE CURRENT LONG-LEAD OUTLOOKS Note: For Graphical Displays of the Forecast Tools Discussed Below See: http://www.cpc.ncep.noaa.gov/products/predictions/90day/tools/briefing CURRENT ATMOSPHERIC AND OCEANIC CONDITIONS Oceanic and atmospheric observations reflect La Niña conditions. In December 2021, below-average sea surface temperatures (SSTs) across the central and eastern equatorial Pacific Ocean were consistent with a mature La Niña. With the exception of the westernmost Niño-4 region, which warmed to -0.2°C at the end of the December, the other Niño indices were between -0.4°C and -1.1°C during the first week of Jan 2022. Below-average subsurface temperatures weakened east of the Date Line, reflecting the slow eastward movement of positive temperature anomalies, at depth, from the western into the central Pacific Ocean. However, below-average subsurface temperatures still dominated the eastern Tropical Pacific from ~200m to the surface. Low-level easterly wind anomalies and upper-level westerly wind anomalies prevailed over the east-central and eastern Pacific Ocean. Enhanced convection persisted near Indonesia and the western Pacific, while suppressed convection remained over the Date Line. The Madden-Julian Oscillation (MJO) weakened during early Jan after slow propagating across the Western Pacific during December. Destructive interference with the ongoing La Niña has likely resulted in the weakening, though the Niño4 SST index was also likely slightly warmer due to this interaction. The MJO is not likely to play a large role in the observed seasonal patterns of temperature and precipitation. PROGNOSTIC DISCUSSION OF SST FORECASTS The CPC SST consolidation for the Niño-3.4 region depicts negative SST anomalies remaining at or below -0.5 degrees C through FMA and then near average from the late spring through the summer and autumn of 2022. The North American Multi Model Ensemble (NMME) ensemble mean forecast for the Niño-3.4 SST anomaly depicts a slightly slower transition to near average during the next six months. The official CPC/IRI ENSO outlook is for La Niña to continue into the Northern Hemisphere spring (67% chance during MAM 2022) and then transition to ENSO-neutral (51% chance during AMJ 2022). PROGNOSTIC TOOLS USED FOR U.S. TEMPERATURE AND PRECIPITATION OUTLOOKS Dynamical model guidance such as the North American Multi-Model Ensemble (NMME) and the Calibration, Bridging, and Merging (CBaM) version of the NMME were used through lead 5. La Niña temperature and precipitation composites were a major tool relied upon through MAM 2022. The consolidation tool, which includes NMME input and various statistical tools, was also used especially after the predicted transition to ENSO-neutral conditions by late spring. At longer leads, such as 7-13 (ASO 2022 - FMA 2023), trends (as represented by OCN) played a larger role. PROGNOSTIC DISCUSSION OF OUTLOOKS - FMA 2022 TO FMA 2023 TEMPERATURE Only minor adjustments were made to the previous temperature outlooks, released in Dec 2021, as La Niña continues to be the major contributor to the predicted climate state during FMA and MAM 2022. Odds for above normal temperatures were decreased across Southern CA and Arizona, reflecting the latest model guidance and consolidations. Odds for above normal temperatures were increased in the Rio Grande, as the confidence around La Niña and the corresponding impacts are just slightly higher as the lead time to FMA is now shorter. Correspondingly, odds for below normal temperatures were increased for parts of southeastern Mainland Alaska and the Alaska Panhandle. Through the spring of 2022, odds for above normal temperatures were increased across much of the Upper Mississippi Valley in response to the latest model guidance and a current lack of snowpack, which is not likely to recover dramatically. This outlook is contrary to the signal from trends in that region, so odds are modest. The summer (JJA) 2022 temperature outlook generally favors above normal temperatures, with only a small reduction in the odds made over the Northern Rockies as compared to last months' outlooks, as new model guidance for that period indicates a cooler signal. The outlooks for JAS 2022 through JFM remain largely unchanged, reflecting OCN based information. PRECIPITATION The precipitation outlooks for FMA and MAM 2022 are consistent with La Niña composites and recent model guidance. Increased odds for above normal precipitation in the Ohio Valley and in the Northern Rockies reflect a bit more amplified pattern and reduced uncertainty relative to last month’s outlooks due to shorter lead time. That increased certainty is also translated to the MAM 2022 outlook, where odds of below normal precipitation were increased in the Four Corners region, and a slight tilt toward above normal precipitation was added to the northwestern CONUS, reflecting the latest model guidance. Outlooks for AMJ through JJA were modestly adjusted to reflect the latest model guidance and ensure continuity in the outlooks. Further out in the outlook package, JJA through SON, trends and a consolidation of statistical tools were the main inputs for the outlooks from JAS 2022 through FMA 2023. The outlooks for JAS through OND generally favor below normal precipitation across an area from the Central Rockies to the Pacific Northwest and above normal precipitation in the Ohio Valley. For next winter, the outlooks reflect the longer-term trends. FORECASTER: Matthew Rosencrans The Climatic normals are based on conditions between 1991 and 2020, following the World Meterological Organization convention of using the most recent 3 complete decades as the climatic reference period. The probability anomalies for temperature and precipitation based on these new normals better represent shorter term climatic anomalies than the forecasts based on older normals. For a description of of the standard forecast tools - their skill- and the forecast format please see our web page at http://www.cpc.ncep.noaa.gov/products/predictions/long_range/tools.html (Use Lower Case Letters) Information on the formation of skill of the CAS forecasts may be found at: http://www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/Outlook/outlook.shtm l (use lowercase letters) Notes - These climate outlooks are intended for use prior to the start of their valid period. Within any given valid period observations and short and medium range forecasts should be consulted. This set of outlooks will be superseded by the issuance of the new set next month on Feb 17 2022 1991-2020 base period means were implemented effective with the May 20, 2021 forecast release. $$