A microclimate is a local atmospheric zone where the climate differs from the surrounding area.

 The Brunello production area is nearly circular and has a 16 km diameter (10 miles). It covers 240.000 hectares (nearly 60.000 acres) of which only 15% are vineyards….

Montalcino town is at 565 metres above sea level. The highest point, the evocatively named, Passo del Lume Spento,[1] the long rettilineo (finally a straight bit of road…if you’ve driven it you may remember it with relief) is nearly 600 metres above sea level. Three rivers, the Asso, Orcia and Ombrone, frame and delimit the Brunello territory, causing humidity that sometimes shrouds the top of the hill in fog, but more often veils the north facing side. My father-in-law used to say that the people in Buonconvento “campano un anno in meno” (they live a year less) because so many of their mornings were spent in fog. Sometimes there is a basin of thick white fog below S.Angelo in Colle. You can usually make out the odd castle or podere floating without context, looking like boats on a great sea. The imposing Monte Amiata (1738 meters), protects the southeast side of Montalcino and acts as a sort of magnet, drawing away hail and heavy rain from this area.

Anyone who lives in Montalcino has daily proof of the different microclimates that abound on this hill. It hails in terrifying stripes or rains in concentric bands around the hill so that you are constantly switching the wipers on and off as you go up the hills. Just yesterday I saw the first almond trees in bloom, splashes of pink standing out in the military shades of winter, here and there from S.Angelo in Scalo up to S.Angelo in Colle. Any higher and the trees are yet to blossom. Next the mandorle blossom will be joined by bright yellow mimosa, blossoming in the protected and warmest spots first. There can be a months difference between the start dates of harvest amongst low-lying and high altitude estates. Our agronomist, Massimo Achilli, has seen a 5° C (9°F) temperature differences between the Valdicava area and S.Angelo on the same day at the same time....

Altitude and aspect (which way the vineyard is facing) are the main factors in determining temperature difference. The situation of a vineyard governs the maximum and minimum temperature in a given day, the thermal excursion (difference between day and night temperatures) and the Winkler Index (the total hours of sunlight per day). All these factors change the way that the grapes mature, not just in terms of how long it takes them to ripen, but also as far as regards their composition and characteristics when ripe and ready to be picked.

 Curioser and curioser….

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[1] The Guttered Candle Pass, so named because of the wind that used to put out all the candles on horse-drawn carriages