Regional Climate Overview - August 2017 - October 2017
Over the last three months (August – October) precipitation was 25–90% below average for western New Mexico and most of the Rio Grande-Bravo region (Figure 1; left). Precipitation was above average for eastern New Mexico and a small area near Laredo, Texas. Temperatures were above average (0–3 °F; 0–1.7 °C) for most of New Mexico and West and South Texas (Figure 1; right). Pockets in eastern New Mexico and Southwest Texas near Laredo experienced temperatures 0–3 °F (0–1.7 °C) below average.
Figure 1 (above): Percent of average precipitation (left) and departure from average temperature in degrees F (right), compared to the 1981–2010 climate average, for 8/1/2017–10/31/2017. Maps from HPRCC.
Temperatures from November 1–14 were 0–8 °F (0–4.4 °C) above average for all of New Mexico and most of Texas (figure not shown). Precipitation over the same time period was 0–50% below average for most of Texas and New Mexico. Exceptions were the Paso del Norte region, from Las Cruces, NM to El Paso, TX, and southernmost Texas, where precipitation was 125–800% above average.
In August to October, below-average temperatures were observed, mainly in western and northern Coahuila, breaking the increasing temperature trend throughout the summer. Southern Chihuahua and western Durango kept the warmer-than-normal signal, where anomalies reached 5.4 °F (3 °C) above average (Figure 2, left). The regions with the highest number of days above 104 °F (40 °C) were located in most of Sonora, and to a lesser extent in northern Nuevo León (Figure 2, right).
Figure 2 (above): Temperature anomalies in °C (left) and number of days with maximum temperatures at or above 40 °C (104 °F) (right) for August–October. Maps from SMN.
The highest amount of rainfall (in mm) was located in southern Sinaloa and in southern Tamaulipas, and smaller amounts were concentrated in northern Baja California (Figure 3, left). Most of Northwest Mexico ended this quarter below normal, but the situation was different for most of the northern and northeastern parts of the country, mainly in the corridor from northern Coahuila to Zacatecas, which were wetter than normal (Figure 3, right).
Figure 3 (above): Accumulated precipitation in mm (left) and percent of normal (right) for August–October. Maps from SMN.
Abnormally dry conditions remained in western New Mexico over the past month, according to the North American Drought Monitor (NADM) (Figure 4). Abnormally dry conditions also developed in areas of Central and western Texas. Moderate drought conditions remained in southern Texas and South Tamaulipas--drought conditions in these areas are predicted to persist through February, according to the U.S. Seasonal Drought Outlook. Drought is predicted to develop in Southwest New Mexico and most of Texas by February.