Editing Geography of Ecuador (section)

=== The Sierra ===

Temperatures in the Sierra do not vary greatly on a seasonal basis; the hottest month averages {{convert|16|°C|1}} and the coolest month, {{convert|13|°C|1}} in the upper elevations. Diurnal temperatures, however, vary dramatically, from cold mornings to hot afternoons. The almost vertical sun and the rarefied air in the higher Sierra region allow the land to warm quickly during the day and lose heat quickly at night. Mornings typically are bright and sunny, whereas afternoons often are cloudy and rainy. In general, rainfall amounts are highest on exposed locations at lower altitudes. Rain can also vary on a local basis. Sheltered valleys normally receive {{convert|500|mm|in|1|sp=us}} per year, whereas annual rainfall is {{convert|1500|mm|in|1|sp=us}} in Quito and can reach {{convert|2500|mm|in|1|sp=us}} on exposed slopes that catch rain-bearing winds. On a seasonal basis, the driest months are June through September.

The climate in the Sierra is divided into levels based on altitude. The tropical level ({{convert|400|to|1800|m|ft|0|sp=us|disp=sqbr}}) has temperatures ranging from {{convert|20|to|25|°C|°F|1}} and heavy precipitation. The subtropical level ({{convert|1800|to|2500|m|ft|0|sp=us|disp=sqbr}}) has temperatures from {{convert|15|to|20|°C|°F}} and moderate precipitation. The temperate level ({{convert|2500|to|3200|m|ft|0|sp=us|disp=sqbr}}) has a year-round temperature in the range of {{convert|10|to|15|°C|°F}} and an annual rainfall of {{convert|1000|mm|in|1|sp=us}}. The temperate level experiences rainstorms, hailstorms, and fog. Winter, or the rainy season, lasts from January through June, and the dry season or summer from July through December. Most rain falls in April. There also is a short rainy period in early October caused by moisture penetrating the Sierra from the Oriente. Quito and most other populated areas in the Sierra are located at this temperate level. The cold level extends from the temperate zone to {{convert|4650|m|ft|0|sp=us}}. Here, average temperatures are {{convert|3|to|9|°C|°F|1}}, and the precipitation often appears in the form of rain, hail, and thick fog. Above {{convert|4650|m|ft|0|sp=us}} is the frozen level, where peaks are constantly capped with snow and ice, and temperatures range from below {{convert|0|to|3|°C|°F|1}}. Precipitation frequently is in the form of snow, fog, and rain.