Predicting Sunset Colors

Reading time: 10-15 minutes    

     A classic shot that landscape photographers tend to chase after is the perfect sunset or sunrise—a scene that surrounds your subject with a sky of vibrant hues of reds, oranges, and pinks. Being at the right time and place is crucial for this shot, as it requires light to be hitting your subject at the perfect angle, though planning isn’t always straightforward.

     We can check the weather forecast many times, believing that the conditions are ripe, only to get our hopes dashed by grey skies or flat light. And while that’s not to say that these conditions aren’t conducive to a great photograph (anything is, with an open mind), we aren’t here to waste time—we want a beautiful sunset! 

     This guide serves as a basic resource to help predict how the sunset or sunrise might look, based on the weather forecast. And while forecasting sunsets may not be an exact science, I personally believe that being so excited at the possibility of a beautiful scene that it gets you out and shooting is really what it’s all about.

     This article has three sections. I’ll go over the factors that contribute to a nice sunset, how to use the weather app to make your forecast, and at the end there will be an example of going to the location and checking your prediction. I use the free weather app Windy but any other app that tells you cloud height and wind speed should do.

     Disclaimer: The weather is inherently unpredictable and chaotic so the perfect conditions cannot be guaranteed. However, learning the ideal conditions can help you be smart about when to go out and shoot to get the best chances at a beautiful sunset. For the purposes of this article I’ll be referring to sunset, however the same principles apply for sunrises.

The Main Factors Contributing to Sunset Colour


1. Little to no low cloud coverage

2. No low lying clouds blocking the sun’s light during sunset

3. Presence of high and/or medium height clouds

4. Calm winds mean your prediction is more reliable, faster winds means the scene is prone to change quickly

     If I’m doing a quick glance at weather apps to decide if I should go out or not, the three main factors I look for are: Cloud Height, Wind Speed, and Low/Thick Cloud Direction. Essentially, we want to know if the sun’s light will hit the right clouds.

Cloud Heights and their Colours
Source: NOAA.

Source: NOAA. Read more here:

     The colours of a sunset are predicted by the height and density of clouds in the atmosphere. Low clouds will not give you much colour, as opposed to medium and high clouds. The density is how thick or how much water vapour the cloud holds. This is usually given as a percentage within weather apps. Therefore, the first lesson to learn is that the density of low clouds present at the time of sunset should be close to zero or low (<40%). This is to ensure that the light from the sun actually hits the medium and high clouds, which is what gives them colour. The higher up the clouds are, the more the light can refract and bend.

     Medium clouds tend to catch orange hues as the sun sets, and then become pink as the sun sets below the horizon. High clouds will generally turn to a beautiful burning red. Though medium and high clouds make for gorgeous colours, if the density is too high, they won’t catch and reflect any colour. Therefore, the second takeaway here is that the clouds must not be too sparse or too dense (30%-70% is a nice sweet spot).

The higher the clouds, the more apparent the shift from yellow to orange to red. RX100iii, January 2024.

Wind Speed

     This is a factor often overlooked but is critical in making the decision to go out or not. Since forecasts are given in chunks of time such as 1hr, 3hrs, etc. (vs real time), it’s important to keep in mind how the atmosphere and clouds will evolve and scatter. If there’s low wind, then cloud forecasts can be very reliable. If it is quite windy, then the clouds will scatter and the heights could change, creating unpredictability. But it also means that if a forecast is less than ideal, the presence of wind can change the initial prediction—for better or for worse. You’ll just have to go to find out! If you’re not too far from your location, always survey the sky with your own eyes and feel it out. I've personally found that wind speeds faster than 10km/h can be conducive for cloud scattering.

     The main point here is that wind scatters, moves, and disperses clouds. The slower the wind speed is, the more reliable the cloud prediction is.

Low or Thick Cloud Direction

     Even if the first three conditions are met, you can find yourself disappointed if some low clouds or thick/dense clouds block the sun as it is setting. Remember, clouds only catch colour if the sun’s light hits them. If there are some thick low-lying clouds on the horizon and in the direction of where the sun will set, then that light will be blocked. So it’s important to check before you head out if any low clouds will be present in that direction. The final point here is to ensure that no low or thick clouds will be blocking the sun’s light from hitting other clouds.

4 Point Summary

Here are the four points and two questions you can ask yourself as you read the forecast:

Will the sun’s light be blocked?

1. Low cloud coverage should be minimal (<40%)

2. No low, heavy, or thick clouds in the direction of the sunset (or sunrise)

WIll the clouds that catch colour be present?

3. Medium and/or high clouds should not be too dense (30% to 70% is a good sweet spot). Medium clouds: orange during sunset, pink after sunset High clouds: Red

4. Calm winds mean your prediction is more reliable. Faster wind speeds mean the clouds will change rapidly, making any prediction of the sunset’s color better or worse. In my experience 10km/h+ winds can shift clouds enough in the span of an hour to make a difference

The goal of all this is we want to see the sun’s light hitting the right clouds.


Additional Contributing Factors (optional):

     Other factors contributing to sunset/sunrise quality are listed below. You do not have to always take these into account as they aren’t as prominent but are here for your reference:

1. Humidity and air quality: water vapour and particulates in the sky affect light quality. The more humid or polluted a sky is, the dirtier the air that the sun’s light has to pass through

2. Season: During winter months, sunsets last longer due to sun’s path. Colours are more vivid due to less water vapour in the air.

3. Sun’s Movement: the sun’s path changes throughout the year, making sunsets longer or shorter depending on the season. Spring/Fall equinox are the shortest, while during Winter/Summer the sunset lingers longer

4. Recent rain/storms: Right after a rain/storm is the most vivid colours you can see—the rain washes away particulates in the air, allowing for cleaner light to hit the clouds

5. Cloud formations: cirrus, cumulus, etc. (if after a certain sky texture or feature)


      Now we know the basics, let’s see this in action! For this example/walkthrough, we’ll be using Windy as our weather app and the 4 Point Summary as our guideline. I like this app because it’s comprehensive and has many features and options. However, most other weather apps will be sufficient.

     There’s a few things to remember, but once you learn how to check for the conditions and practice it a few times, this process is really fast and quite easy to do.

Predicting the Sunset with Windy

     In this section, we’ll go through how to predict the sunset’s conditions using Windy (a free weather app). You can use any other weather app which relays cloud height data and wind speed with the concepts talked about on here.

     As you open up Windy, click on the options button on the bottom right (☰). From there select the clouds options (Fig. 1a). The different visuals for each cloud height (high, medium, low) will be shown. The overall cloud view is selected by default. The satellite feature is also available if you want to see the view in real-time (with a small time delay).

Fig. 1a - Cloud forecast options in Windy. Fig. 1b - Forecast model options.

     If you scroll all the way down, you’ll be able to select different forecasting models (Fig. 1b). I find the ECMWF (European Centre for Medium-Range Weather Forecasts) and GFS (Global Forecast System) to be the most accurate and they are the two I usually check on a quick look. However, the different models are available if you’d like to compare different data to be more certain of your prediction. If only choosing one, ECMWF is the most reliable and is the default.

     From there, return to the map and click anywhere. This will give you the reading where the crosshairs lie. Navigate to your intended location and select the different cloud height options. At the bottom of the screen, there is a timeline that you can scroll through to advance the forecast. Advance it to roughly around the time sunset should occur. Make sure to check one hour before and after as well to get a good sense of how the clouds could develop.

Fig. 2a - ECMWF low clouds Fig. 2b - GFS low clouds

     In my case, I started with the ECMWF model and checked the high, medium, and low clouds for around 4pm (sunset was around 5pm). Both the medium and high cloud density were at 0% (not shown), and so was the low cloud (Fig. 2a). I found this to be interesting as the morning started off very cloudy. Wanting to be sure, I double checked with the GFS weather model, Fig. 2b, and found that the low clouds were showing at 36% instead (medium and high were also at 0%). 

This quick comparison tells me two things right away:

1. We’ll most likely have a clear view of the sun prior to sunset (i) and (ii) it’s possible that the sun’s light will be blocked as it dips close to the horizon (see west horizon, Fig. 2b)

2. There are no medium or high clouds present around sunset, so I shouldn’t expect any colour (iii)

     I hesitated on going because the sunset prediction indicated a lack of colour in the sky—a very regular and boring sunset in my opinion. However I made sure to check the wind (Fig. 2c) to see how it could develop. It showed around 11km/h which isn’t fast, but it isn’t calm either. Meaning there’s a chance that it could scatter any low clouds upwards, therefore catching colour (iv).

Fig. 2c - ECMWF Wind forecast

From the 4 point summary:

i. Low/minimal low cloud coverage (0% and 36%)

ii. Thick low clouds are in the direction of the sunset

iii. Both weather models showed medium/high clouds at 0%, low chance of colours

iv. Wind is not calm but not fast. Slight chance of clouds moving upwards

     Overall, the prediction was a boring sunset with little cloud colour and it might get cut short due to thick low clouds looming. But there’s a chance of wind scattering the clouds upwards. The prediction suggests that conditions are not the most certain but despite this I decided to go anyway! After all, sunny days in the wintertime can be quite rare.

On Location, Photographing the Sunset and Checking the Prediction

    We arrived about an hour before sunset and scoped out the area. I noticed that the skies were generally clear. However on the western horizon, we could see that there were some light clouds above where the sun would set. These looked to be maybe medium clouds. If my prediction was correct about the wind speed, this should hopefully scatter and give us color. 

     Additionally, we also noticed the low clouds that were predicted to be lingering. Meaning that if the clouds do catch colour, our time may be limited.

Arriving an hour before sunset. Yashica Mat-124G, Portra 160, January 2024. Thank you to Aden Camera for the scans. Also a big thanks to John for lending me his TLR and Michelle for taking this shot on her Ricoh GRiii.

      With a bit of time before sunset, we walked around the park and saw a man walking his cat. He was hanging around the shore with his cat perched upon his shoulders while he was taking a call. I figured that even if we didn't get a nice sunset, this scene made the whole trip worth it. Seriously, how often do you see this happening? Much less in the wintertime!

      As sunset approached, we made our way to the spot closest to the western horizon to get a clear view. Two things stuck out to me- the clouds DID scatter upwards (seen in the top half of the photo below) and that sunset would be a bit blocked at the end but it wouldn’t be too bad. The low clouds along the horizon weren’t as prominent as the forecast had predicted.

Colonel Samuel Smith Park. Yashica Mat-124G, Portra 160, January 2024

     After sitting for a while and admiring the sunset, we started feeling a little cold from the open space and chilly winter air.  So we decided to walk back through the park and towards the car. However, as we did, the sun began to set lower and lower below the horizon. This meant that those medium and high clouds started to finally catch colour!

Sunset and its cloud colours. Yashica Mat-124G, Portra 160, January 2024.

     This last photograph was the one shared earlier in the article, though captured on my Sony point and shoot. Despite the forecast mentioning that sunset colors were highly unlikely, we were greeted with a wonderful sky palette to end the day.

     Reflecting on this experience, I am glad I took the chance and went out for this sunset. At that point in the season, winter had been quite cloudy and sunshine was sparse. So to be in open space and breathe cold winter air while enjoying the vivid colours was a treat. I don’t even think my favourite image from the day was of the sunset—it was certainly the man with his cat!

     Despite this, going to shoot was worth it. Whether or not the sun or landscape is the subject of your photograph, I think being excited to go out somewhere is just as good—as long as you make the effort to get out there and shoot! And I feel that despite its usefulness, weather apps and being able to predict sunset colours is just a catalyst for that experience. Despite many days of grey skies or gloomy weather, I know I can count on there being a nice sunset or sunrise eventually- so go ahead and chase the sun! After all, sunsets are an inevitable beauty.


Thank you to the people who provided their feedback on this article. A big thanks to Tim S. for his extensive comments and edits.

Thank you to Aden Camera for their quick service and high quality scans.

Thank you to John for sharing the joy of TLR cameras and to Michelle for chasing and documenting this sunset with me.

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