Precipitación Y Temperatura: En febrero, Arizona experimentó precipitación media a precipitación por arriba del promedio, mientras Nuevo México experimento precipitación que osciló entre media a por arriba de la media (Fig. 1ª). Temperaturas muy por arriba del promedio se observaron en la mayor parte de la región; el este de Nuevo México experimento las temperaturas mas altas registradas (Fig. 1b). Las primeras dos semanas de marzo fueron secos para el Suroeste, una inversión de las condiciones mojadas del inicio del invierno (Fig. 2ª). Temperaturas por arriba del promedio se observan en marzo también (Fig. 2b) y incluyen un serie de temperaturas casi record en el mediados de marzo. Para el año pluviométrico, el Suroeste ha experimentado precipitación y temperaturas por encima del promedio (Fig. 3). (Resumen completo)
This event began in fall 2016, ended in early February 2017, and throughout the period oceanic and atmospheric indicators generally hovered near the boundary between weak La Niña and ENSO-neutral conditions. According to CPC criteria, this was a weak La Niña event (but just barely); other agencies use slightly different criteria (see last month's ENSO tracker for details), highlighting the difficulty in categorizing these borderline events. This weak strength also affects how precipitation and temperature patterns are interpreted. In the Southwest, a La Niña event is more likely than not to bring warmer- and drier-than-average conditions over the cool season, but a weak La Niña event might not even stand out from the normal seasonal variation of typically dry southwestern winters (Fig. 5).
So how did this La Niña event stack up compared to expectations? (read more)
Oceanic and atmospheric indicators of the El Niño-Southern Oscillation (ENSO) are currently neutral (Figs. 1-2), and most forecast agencies predict they will remain so through spring 2017. These agencies also forecast that El Niño conditions could return in mid-to-late 2017, but given the uncertainty of ENSO forecasts associated with the “spring predictability barrier,” we can get only a general sense now of the range of outcomes likely later this year (i.e. La Niña is basically off the table). More detailed information about the timing or intensity of a possible El Niño will start to become available in late spring or early summer. (read more)
Precipitation & Temperature: February precipitation totals were average to above average in Arizona and ranged from below to above average in New Mexico (Fig. 1a). February temperatures were much-above average across most of region, including record warmest temperatures in eastern New Mexico (Fig. 1b). March precipitation to date has been dry across the Southwest, reversing the wet trends of early winter (Fig. 2a). March temperatures have also been above average across the Southwest (Fig. 2b), including a run of near-record temperatures at the time of this writing. Water-year precipitation and temperature are both above average across much of the Southwest (Fig. 3). (read more)