Forecast - December | January | February
The three-month NOAA temperature outlook (December-February; Figure 5) favors chances for above-average temperatures for all of New Mexico and Texas through February, reflective of continued La Niña conditions in the tropical Pacific Ocean through the winter.
Figure 5 (right): NOAA three-month temperature outlook (December-February). Forecast made on November 16, 2017 by CPC.
The forecast from CONAGUA´s Servicio Meteorológico Nacional (SMN) for December predicts below-average minimum temperatures in Southeast Sonora, western Chihuahua, northern Sinaloa, and southern Coahuila and Nuevo León (Figure 6). Above-average conditions are predicted for southern and Southwest Chihuahua, Central Coahuila, Nuevo León and Tamaulipas. For January, SMN predicts below-average minimum temperatures in northern Baja California, Southwest Chihuahua and Coahuila. Above-average temperature anomalies are predicted in Central Baja California, eastern Sonora, Chihuahua, Coahuila, Nuevo León and Tamaulipas.
Figure 6 (above): Predicted minimum temperature anomalies for northern Mexico (in °C) for December 2017 (left) and January 2018 (right). Forecast made on November 1, 2017 by SMN.
The NOAA three-month precipitation outlook predicts chances for below-average precipitation for all of New Mexico and Texas, except for the northernmost points of both states (December-February; Figure 7). Precipitation forecasts reflect the projections for continued La Niña conditions in the tropical Pacific Ocean through the winter. La Niña conditions tend to lead to below-average precipitation in the Southwest U.S. and northern Mexico.
Figure 7 (right): NOAA three-month precipitation outlook (December-February). Forecast made on November 16, 2017 by CPC.
For December, the SMN precipitation outlook predicts above-average conditions in Baja California and Northwest Sonora, and below-average conditions in Baja California Sur, Southeast Sonora, Chihuahua, Coahuila, Nuevo León, Tamaulipas, San Luis Potosí, Zacatecas, Durango and Sinaloa (Figure 8). The precipitation forecast for January shows above-average conditions in Baja California Sur and northern Sonora and Chihuahua, and average to below-average conditions in the remainder of the country.
Figure 8 (above): Predicted precipitation anomalies for northern Mexico (in %) for December 2017 (left) and January 2018 (right). Forecast made on November 1, 2017 by SMN.
According to the National Interagency Fire Center (NIFC), fire risk is normal for New Mexico and Texas through December (Figure 9). However, La Niña conditions, projected to continue through the winter, are predicted to bring dry and warm conditions to the Southern Plains, including Central Texas, by January, making grasses and brush more receptive to fire. In Mexico, the potential for forest fires will be within the normal range for the northern part of the country through January.
Figure 9 (above): Fire outlook for December (left) and January (right). Red shading indicates conditions that favor increased fire potential. Green shading indicates conditions that favor decreased fire potential. Forecast made on November 13, 2017 from NIFC and SMN.
El Niño-Southern Oscillation
As of early-November, the tropical Pacific Ocean and atmosphere were exhibiting weak La Niña conditions (IRI; NOAA). Weak La Niña conditions are predicted to continue through approximately February-April 2018, with an ~65-75% probability of occurrence, according to the official CPC/IRI outlook (Figure 10). La Niña events generally lead to above-average temperatures and below-average precipitation in the Southwest U.S. and northern Mexico.
Figure 10 (right): ENSO probabilistic forecast from IRI.
For more ENSO information:
English: http://iri.columbia.edu/our-expertise/climate/enso/enso-essentials/ and http://www.ncdc.noaa.gov/teleconnections/enso/.
Spanish: http://smn.cna.gob.mx/es/climatologia/diagnostico-climatico/enos y http://www.smn.gov.ar/?mod=biblioteca&id=68