Fog Probability
How likely fog is to form. High scores mean misty, atmospheric conditions for moody landscape and sunrise photography.
What is Fog Probability?
Technical detailsFog Probability predicts the likelihood of fog forming by combining humidity, temperature, dewpoint, wind, and time of day. Scores are highest when the air is saturated with moisture and conditions are calm—exactly when fog tends to appear. The score peaks during the prime fog window from late night through early morning, when radiation fog is most common.
Templates using this field
Related rule templatesPhotography tip
How to use this conditionMoisture-first fog probability. Scores high when air is saturated even with good visibility. Low visibility alone (haze, smoke) scores zero without moisture confirmation.
Fog Probability in photography
In depthFog Probability tells you when to set your alarm for a foggy sunrise shoot. Fog creates some of the most compelling photography—soft diffused light, simplified compositions, mysterious depth, and light beams cutting through the mist. But chasing fog means early mornings and long drives, so you need a forecast you can trust.
The score combines humidity, dewpoint, temperature, wind, and time of day to predict when fog will form. Calm conditions with moisture-saturated air score highest, especially during the prime fog window from late night through dawn—exactly when radiation fog is most likely to appear. Clear overnight skies boost the score further, since the ground cools faster and fog forms more readily.
Whether you're planning a misty lake sunrise, waiting for fog to roll through a valley, or hoping for light beams in a forest, this is the number to watch. Set your threshold around 70-80% for notifications. Scores above 80% mean conditions are strongly lined up—grab your camera.
Frequently asked questions
Common questionsWhat is Fog Probability?
Fog Probability predicts the likelihood of fog forming by combining humidity, temperature, dewpoint, wind, and time of day. Scores are highest when the air is saturated with moisture and conditions are calm—exactly when fog tends to appear. The score peaks during the prime fog window from late night through early morning, when radiation fog is most common.
How does Fog Probability affect photography?
Moisture-first fog probability. Scores high when air is saturated even with good visibility. Low visibility alone (haze, smoke) scores zero without moisture confirmation.
What values are typical for Fog Probability?
Fog Probability typically ranges from 0.0% to 100.0%. PhotoWeather monitors these values to help you identify ideal conditions for your photography goals.
How is Fog Probability calculated?
Fog Probability is an advanced derived condition calculated from multiple weather parameters including Visibility, Temperature, Dew Point, Relative Humidity, Vapor Pressure Deficit. PhotoWeather's algorithms analyze these factors to provide a single, easy-to-understand score for this photography opportunity.
Typical values
Value rangeRelated fields
Similar weather conditionsAurora Quality
Combines aurora activity with viewing conditions (darkness, cloud cover, visibility) to provide photography-ready aurora quality scores. Aurora activity is OVATION-aware from the compute step.
Blue Hour Quality
Evaluates atmospheric conditions for blue hour photography quality. Scores sky clarity, cloud type suitability (high thin clouds ideal), visibility, and calm conditions.
Fiery Red Sky Potential
Predicts the chance of vivid red, orange, and pink sunrise or sunset color. Best when the sun has a clear opening near the horizon, some clouds are ready to catch the light, and low clouds are not blocking the show.
Golden Hour Potential
Atmospheric suitability for golden hour photography across extended time window around golden hour periods
Golden Clouds Potential
Cloud formation suitability for golden hour photography across extended time window around golden hour periods
Cloud Drama Score
Analysis of cloud formations and atmospheric conditions for dramatic sky photography
Storm Intensity
Storm intensity analysis combining precipitation, wind conditions, atmospheric pressure, visibility, GFS simulated radar reflectivity, and wind shear for enhanced storm organization detection.
Frost Probability
Frost formation probability combining temperature, dewpoint spread, cloud cover, and wind analysis
Rainbow Probability
Probability of visible rainbow formation based on solar geometry and precipitation patterns
Coastal Drama Score
Analysis of coastal conditions combining wave dynamics, atmospheric conditions, and lighting for dramatic seascape photography. Evaluates wave height, swell patterns, spray potential, and atmospheric drama factors.
Atmospheric Clarity Score
Comprehensive atmospheric clarity analysis for landscape and astrophotography using CAMS aerosol optical depth, particle composition (dust, smoke, sea salt), particle size distribution (Ångström exponent), and visibility conditions.
Light Breakthrough Potential
Likelihood of sun breaking through clouds creating dramatic rays and dappled light patterns. Best with partial cloud cover (40-70%) and some sunshine reaching the surface.
Soft Light Index
Quality of diffused light for portrait and product photography. High scores indicate soft, even lighting that minimizes harsh shadows - the 'giant softbox' effect.
Cloud Texture Score
Rates how visually interesting the clouds are - distinguishing dramatic formations from boring flat overcast. High scores indicate structured clouds with good light transmission.
Overcast Flatness
How flat and boring the overcast is. HIGH scores indicate uniform gray sky with no breaks or texture - generally unfavorable for most photography. LOW scores indicate breaks, texture, or clearing.
Dewpoint Spread
Temperature difference between air temperature and dew point
Visibility
Horizontal visibility distance
Relative Humidity
Moisture content relative to saturation
Wind Speed
Wind speed at 10 meters above ground
Learn more
Photography guidesGet started with PhotoWeather
Create rules using Fog Probability and get notified when conditions are perfect for your locations.
Create Free Account