La Pampa Province - Geography and Climate

Geography and Climate

Situated in the middle of the pampas, the low, flat steppe receives 500 mm of rain a year, diminishing towards the West. The low humidity and temperate weather result in high contrast in temperature between day and night, which is reflected in the vegetation of the region.

Summers are warm throughout the province, with warmer days in the west (about 32°C, or 90F) than in the east (30°C, or 86F) and cool nights, ranging from 16°C (61F) in the north to 14°C (57F) in the south: the thermal amplitude is thus quite remarkable. Heat waves are frequent, and temperatures reach over 40°C (104F) sometimes. These are often followed by severe storms and much colder periods, where nights can be below 10°C (50F). By early March nights are already noticeably cooler, and April usually brings the first frosty nights. Averages range from 19°C (66F) to 22°C (72F) during the day, and 7°C (45F) to 10°C (50F) at night, with dryer conditions than in the summer. Winters in La Pampa are usually dry and sunny, with cool days and quite cold nights, and some marked variations between warmer and colder periods. Daytime temperatures range from 15°C (59F) in the north and west, to about 12°C (54F) in the southernmost areas. Nighttime lows range from about 3°C (37F) in the northeast corner to around 0°C (32F) or slightly below freezing in many southern and western areas. That being said, northerly winds occasionally bring days of up to 25°C (77F), while southern winds can keep daytime highs below 5°C (41F). Nights below -5°C (23F) are quite common everywhere, with temperatures below -10°C (14F) possible in most areas. Spring is marked by wide variations and periods of drought followed by severe thunderstorms: it is the season of hail, and it is not uncommon to see temperatures reach 35°C (95F) on one day, and then fail to reach 15°C (59F) two days later, with frost possible until October and perhaps later.

Overall, precipitation ranges from about 700 mm in the east/northeast, to 500 mm in the centre (agricultural frontier), and values below 400 mm in the south and west.

Northwestern La Pampa is part of the pampa húmeda, adjacent to the Province of Buenos Aires. The influence of the Cuyo region can be seen in the west, with a low mountain range of 600 meters.

There are only two major rivers in the province: the Colorado ("Red River") on the border with the Province of Río Negro, and the Salado ("Salty River") crossing it. The Salado's level has been dropping, as its tributaries in the Province of Mendoza are diverted for irrigation.