Climate · Explainers
How to Read a Wind Rose: Direction, Speed and Frequency
To read a wind rose, match each spoke to the direction the wind came from, read its length against the frequency rings, and use the colors to identify…
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Narrow these results →Climate · Explainers
How to Read a Climograph: Temperature and Precipitation
To read a climograph, identify the months, temperature line, precipitation bars and their separate labeled axes. Read each value on its own scale, then compare the seasonal pattern.…
Climate · Explainers
Coriolis Effect: Which Way Does Moving Air Deflect?
For horizontal motion, the Coriolis contribution acts to the right of travel in the Northern Hemisphere and to the left in the Southern Hemisphere. Right and left follow…
Climate · Comparisons
Relative Humidity vs Dew Point: How to Read the Numbers
Relative humidity is the percentage ratio of actual water vapor pressure to saturation vapor pressure at the air temperature. Dew point is the temperature at which cooling would…
Cities & capitals · Explainers
Urban Heat Islands Explained: Why Cities Can Be Hotter
An urban heat island is an urban area that is warmer than its surrounding reference area. Built surfaces, reduced vegetation, building geometry and human-generated heat can all contribute.…
Climate · Map guides
Weather Fronts Explained: Four Types and Their Map Symbols
A weather front is a transition zone between air masses with contrasting properties, especially temperature. Cold and warm fronts describe one air mass replacing another at the surface.…
Climate · Explainers
Köppen Climate Classification: How to Read the Climate Codes
The Köppen climate classification groups places by long-term temperature and precipitation patterns. Its five main groups are tropical, dry, temperate, continental or cold, and polar. Additional letters describe…
Climate · Explainers
Is It a Rain Shadow? Test the Terrain, Wind and Precipitation
A rain-shadow explanation is supported when mountains intercept moisture-bearing winds and comparable long-term records show a wetter windward side and drier leeward side. Windward means facing the incoming…
United States · Climate · Map guides
White Christmas Probability Map: Historical U.S. Snow Odds
Explore a White Christmas probability map based on NOAA data, with historical snow-cover odds for 24 U.S. stations. Learn what the numbers mean, not a forecast.
Climate · Map guides
Lake-Effect Snow Belt Map: Great Lakes Regions Explained
Explore representative Great Lakes snowbelts in the United States and Canada, with an original locator map, regional key and wind-fetch diagram.
United States · Climate · Map guides
Hail Alley Map: Where Hail Is Most Common in the United States
A map of frequent hailstorms can look different from a map of the largest hailstones or the costliest roof damage. The distinction starts with what each map counts.Hail…
Climate · Place guides
Caribbean Hurricane Risk by Island
Caribbean hurricane exposure varies sharply over short distances, while phrases such as “outside the hurricane belt” conceal both the counting method and the remaining risk. This comparison applies…