Alsace lies between latitudes 47.5 degrees and 49 degrees north of the equator, giving a long, cool growing season. It is important for the vineyards to make the most of the sun’s rays, and so most of the best vineyards are on south, south west, or south east facing slopes, sheltered from the wind by the Vosges. Average annual rainfall is one of the lowest in France, due to the influence of the Vosges mountains: 500 mm/19 in in Colmar, varying considerably according to site. Most vineyards are at an elevation of between 175 m and 550 m (1,804 ft) in the Munster Valley, above which level much of the mountainside is covered with pine forests. Autumn humidity allows for the production of late-picked vendange tardive—and sélection de grains nobles—wines (see below) in good vintages.