• Rain
    • Rain-Shadows
    • Draught
    • Wind
    • Wind-Gaps


Major Component of Climate and One That Can Be Qualified as the Quantity of Rain Falling Within a Given Area In a Given Period of Time.

“Rainfall Affects Grapevines In Many, Sometimes Conflicting Ways.”

  • VITICULTUREBENEFIT– ~Rain~ Has a Moderates, Cooling or Warming Effect On Temperature In Vineyard. On Frosty Days Rain Can Increase Temperatures
  • VITICULTURECHALLENGE– ~Excessive Rain~ Rain Before Fruit Set Can Cause Millerandage or Coulure (Grapes Don’t Fertilize Properly Due to Cold and Rain)
  • Too Much Rain Before Harvest Dilutes the Grapes/ Wine, Sugar/ Acid Balance
  • Too Much Rain During Summers Pushes Back Harvest
  • For Vineyards Depending On Rainfall Enough Rain is Essential and at Certain Periods to Stimulate Growth and Avoid Water Stress.
  • Water Stress and Excessive Rainfall Can Be Detrimental to Bunch Development, a Fine Balance is Needed to Maximize Quality.

SOIL EROSION– Naturally Occurring Process That Affects All Landforms, Refers to the Wearing Away or Dispatching and Transfer of Sediment or Aggregate of Top-Soil by Natural Forces of Rain or Wind.

HAIL= Rain That Freezes as it Falls to Earth

    • Burgundy
    • Piemonte


Wet Area Separated by Overly Dry Area Separated by Mountains Due to Effect of a High Altitude Mountain Range. Storms “Wall-Up” Against Mountains and Precipitate or Extract Water/ Moisture Leaving Clouds Waterless Before Reaching the Other Side.

  • Windward- “Side”
  • Leeward- “Side”

Rain Shadow Effects of the New World

  • OKANAGAN VALLEY    @Canada, British Columbia  
    • Topography– ~Coast Mountains Range~
  • COLUMBIA VALLEY AVA.     @Washington
    • Topography– ~Cascade Mountains~
  • YAKIMA VALLEY AVA.     @Columbia Valley
    • Geography– Washington, REGION-Yakima Valley AVA.
      • ~Snipes Mountains~   EFFECTS/ Snipes Mountain AVA.
    • Topography– Coast Mountains Range
    • Geography– California, REGION-Central Coast ‘North
      • ~Santa Lucia Mountains~  EFFECTS/ Santa Lucia Highlands AVA.
      • ~Santa Cruz Mountians~  EFFECTS/ Santa Cruz Mountain AVA.
  • CURICO     @Chile
    • Topography– ~Coastal Mountains~
  • NEW ZEALAND      @New Zealand
    • Topography– ~Southern Mountain Range~    
    • Topography– ~Santa Cruz Mountains~
  • SHENANDOAH VALLEY     @Virginia
    • Topography– ~Afton Mountains/ Blue Ridge Mountains~
  • MEDOZA     @Argentina
    • Topography– ~Andes Mountains~

Rain Shadow Effects of the Old World

  • PHATZ     @Germany
    • Topography–  ~Haardt Mountains~
  • ALSACE     @France
    • Topography– ~Vosges Mountains~
  • VALLE D’AOSTA     @Italy
    • Topography– ~Western Alps~
  • DOURO VALLEY     @Portugal
    • Topography– ~Marao Mountains~

DROUGHT= Prolonged Server Deficit of Rainfall In Specific Area

  • Dry Years Often Produce Great Red Wines, But Multiple Years of Deficit of Rainfall is Detrimental to the Vine.
  • Even Though Grapes Are Relatively Drought Resistant They Are Not Invincible. Period of Stress From Lack of Water Will Cause the Vine to Shut Down Fruit Production In an Effort to Stay Alive.

OBTAINING WATER– In Certain Regions Water/ Snow Melt From Mountains is Carried by Various Rivers to the Vineyards Below That Can Be Diverted Off In Channels and Canals and Used For Irrigation.

IRRIGATION= Simulation of Rainfall, Used to Make Up Rain Deficits. Irrigation Allows For the Growing of Grapes In Hot, Arid, Climate Possible.

  • History– Evidence of Grape Growers Using Irrigation Goes Back in Time Babylonians, Chinese, Egyptian, Early South American Civilizations
  • VITICULTUREBENEFITS– Able to Maximize Yields in Table Grapes, Drying Grapes, Bulk Wine by Over Watering Leading to Over Hydration.
  • VITICULTURECHALLENGE– Negative Effects of Irrigation is it Doesn’t Challenge the Roots to Explore or Go Deep into the Soil Profiles.
    **Refer to “CLIMATE/ Rainfall” For Detailed Information
  • Being Able to Use Irrigation is an Enormous Advantage. The Ability to Control When Water is Applied and In What Quantity and Not Leave it to Mother Nature is a Benefit. The Grape Grower Can Control/ Manipulate the Soil/ Vine Growth/ Vigor/ Berry Size.   All Irrigation is Now Done by Drip Systems. Irrigation Can Be Metered Out So Precisely That Each Row by Row Can Be Adjusted to Benefit Complexity of Soils In a Vineyard.
  • Evaporation Rate Determining Factor- Influenced by: Shading, Soil Conditions, Wind Speed, Humidity, Cover Crops, Air Temperature
  • Irrigation Sources- River, Canal, Pond, Lake, Water Tank, Irrigation Lagoon

VITICULTURECHALLENGE– ~Water Abundance~ Vines Grow Vegetative (Leaves, Shoots)

  • ~Water Deficit~ Vegetative Vines Growth Slows and Efforts Are Put In Caring For Fruit

Irrigated Systems of the World

  • DRIPPER SYSTEM IRRIGATION– Delivers Exact Amounts of Water Applied as Drops to Base of Each Vine From Pressure Reducing Plastic Devices. Allows For Precise Amount of Water to Be Used at Precise Time to Precise Area.
    • Allows Irrigation of Undulating Lands and Maximizes Water Supple
    • As a Negative, Drip Irrigation Promotes an Elevated Rooting Zone.
  • FIXED SPRINKLER IRRIGATION– Water is Pumped Through Sprinkler So Water Breaks Up Into Small Drops and Fall to Ground. Downfall is It’s Not Precise and Much of the Water is Wasted
  • TRAVELING OVERHEAD SPRINKLER– Can Cover Large Areas With One Sprinkler and Can Be Used On Multiple Vineyards In a Day.
  • UNDER-VINE MINI-SPRINKLER– Attached to Supple Pipes and Usually On Every Other Row, and Spray In a Circle In a 2-5 Meter Radius.
  • LEAKY HOSE– Hoses Laid Along Every Row of Vines and Holes Punched In Pertinent Positions
  • FURROW IRRIGATION– Water is Funneled Into Furrow Channels the Vines Are Planted In
  • FLOOD IRRIGATION– Water Fed From Supply Canal is Flooded Down the Rows and Absorbed Into the Vineyard
    • Australia
    • Columbia Valley
    • San Jacquin Valley


Perceptible Natural Movement of Air In Form of a Current of Air Blowing From a Particular Direction

  • VITICULTURE- BENEFIT– ~Wind~ Has Moderating Effect, On Vineyards, Decreasing Temperature On a Hot Day and Increase Temperature On a Cold Day. Winds Promotes Healthy Vines by Not Allowing Humidity While Discouraging Bugs, Mildew and Molds.
    • Reduces Canopy and Toughens Skins Resulting In Grapes Denser In Color and Flavors
  • VITICULTURE CHALLENGE– ~High Winds~ Causes Poor Berry Fertilization, Poor Fruit-Set, Wind Stress Broken Shoots, Trellis Collapse, Leaf Damage (Causes Poor Photosynthesis), Photosynthesis Shuts Down When Winds Get Higher Than 15 MPH. Leaf Shade Removal. Hill Sides and Sloops Vineyards Are Generally Exposed to Increased Winds.
    • Callused– Scabbing Where Berries Are Constantly Rubbing Together
    • Windbreak– Barrier, Either Manmade or Natural/ Vegetation to Break the Force of Wind to Avoid Wine Damage or Wind Stress. Natural Windbreaks Are Trees or Shrubs

Winds of the New World

  • Cape Doctor      Geography– South Africa
    • Origins…                         Characteristics…Dry Air, South Easterly
  • Howlers           Geography– Washington/ Columbia Valley
    • Origins…Columbia River
  • Polar            Geography– Western Argentina/ Mendoz
    • Origins…Cold Wind From the South/ Eastern Slope of Andes Mountains
  • Santa Ana’s            Geography– Southern California
    • Origins
  • San Pablo          Geography– Carneros    
    • Origins
  • Sudestada            Geography– Western Argentina/ Mendoza
    • Origins…South-East Wind That Comes From the Atlantic/Uruguay River/ Parana River
  • Westerlys           Geography- New Zealand
    • Origins
  • Wind Machine           Geography- High Valley/ Lake County
    • Origins
  • Zonda            Geography– Western Argentina/ Mendoza
    • Origins…Warming Western Wind That Sweeps Down Off the Eastern Slope of Andes Mountains

Winds of the Old World

  • Alicios           Geography– Carnary Islands
    • Origins…North Atlantic        Characteristics…Cold Air, Water Currant
  • D’Autan            Geography– South-West France/ Gaillac   
    • Origins…East-Central Africa
  • Borda            Geography Italy/ Friuli, Carso      
    • Origins…Adriatic Sea
  • Breva            Geography Lombardia/ Valtallina     
    • Origins…Off Lake Coma
  • Ciezo              GeographyCarinena
    • Origins
  • Foehn    @Generally Term For Down-Slope Winds On Lee Sides of Mountains That Are Producing Rain Shadow Effects
    • Foehn Effect– Dry Warm, Down-Slope Wind That Occurs On the Down-Wind Side of a Mountain Range, Creates a Microclimate That’s Milder & Dryer Than it Should be at Altitude
  • Gregale             GeographyWestern Mediterranean
    • Origins…South of Malta
  • Levant/ Solano             GeographySouthern France/ Spain
    • Origins…Atlantic/ Strait of Gibraltar
  • Libeccio            Geography- France/ Corsica
    • Origins
  • Meltemi           Geography– Crete
    • Origins…Balkan/ Hugary
  • Le Mistrel           Geography– Rhone Valley
    • Origins…Massif Central
  • Ostro             GeographyItaly
    • Origins…Adriatic Sea
  • Ponente              GeographyWest Mediterranean
    • Origins…Atlantic
  • Saharan           Geography– Carnary Islands
    • Origins…North Africa/ Sahara Desert        Characteristics…Hot Air
  • Sirocco            GeographySouthern Europe/ Mediteranean
    • Origins…Sahara Desert
  • Tramontane           Geography- Italy, Spain
    • Origins… Alps/ Northern Italy


Predominate Opening Below a Ridge-Line/ Coastal Low Land Area That Allows Inflow of Fog/ Moisture/ Weather Into a Area. As the Inland Valleys Heat Up, Warm Air Rises Creating Low Pressure Effect This Draws In Cool Misty Pacific Ocean Air Into the Valleys Via Gaps. Wind-Gaps Have a Strong Effect on Many Aspects of Vineyards and Viticulture.

Winds Gaps of the New World

  • Berryessa Gap
    • Geography– California, REGION-Central Valley
      • Gap In
  • Chalk Hill Gap
    • Geography– California, REGION-Napa Valley AVA.
      • Gap In– Mayacamus Mountains
  • High Valley Gap
    • Geography– California, REGION-Clear Lake AVA.
      • Gap In
  • Lamari Gap
    • Geography– Chile, REGION-Limari Valley
      • Gap In– Coastal Range- Tongoy Bay/ Talinay Hills
  • Monterey Bay Gap
    • Geography– California, REGION-Central Coast ‘North
      • Gap In– Coast Mountain Range
  • Rainbow Gap
    • Geography– California, REGION-Temecula AVA.
      • Gap In
  • Rockfish Gap
    • Geography– Virginia, REGION-Shenandoah Valley AVA.
      • Gap In– Blue Ridge Mountains/ Afton Mountains
  • Russian River Gap
    • Geography– California, REGION-Russian River Valley AVA.
      • Gap In
  • Petaluma Gap
    • Geography– California, REGION-Sonoma Coast AVA.
      • Gap In– Coast Range, Between Bodega Bay and Tomales Bay
  • San Francisco Bay Gap    
    • Geography– California, REGION-Central Coast ‘North’ AVA.
      • Gap In– Coast Mountain Range
  • Templeton Gap
    • Geography– California, REGION-Paso Robles AVA.
      • Gap In
  • Van Duzer Corridor Gap    
    • Geography– Oregon, REGION-McMinnville AVA.
      • Gap In– Coast Mountain Range
  • Wallula Gap
    • Geography– Washington, REGION-Walla Walla AVA.
      • Gap In

Winds Gaps of the Old World

  • Gap
    • Geography– Lisbon- REGION-Obidos
      • Gap In– Peniche Peninsula

**Refer to “BIBLIOGRAPHY/ SOURCES” For Details On Scholarly Works Referenced