Lesson video

Hello, my name is Dr.

Robinson, and if there's one thing I enjoy talking about, it's the weather.

Today's lesson is going to look at precisely that.

So let's get started.

Welcome to today's lesson from the unit of maths and the environment.

This lesson is called Understanding Weather Data.

And by the end of today's lesson, we will be able to interpret a weather report.

The lesson will introduce a new keyword, which is forecast.

A forecast is a prediction of a future event occurring, and that's usually based on data.

The lesson is broken into two learning cycles, and we're going to start by understanding a basic weather report.

Most weather forecasts use different symbols to represent different types of weather.

For example, here we have eight different weather symbols.

What do you think each of these symbols might mean? Perhaps pause the video, why you think about this yourself, and then press play when you're ready to continue together.

What did you think? Let's take a look.

The first one, which is labelled A, represents a lightning.

The next one represents windy weather.

C represents cloudy weather.

D represents snow.

E represents sunny weather.

F is sunny but also cloudy as well, so we have sunny intervals.

And G represents rain showers, so it might rain for a bit, stop, rain for a bit more and stop, and stop and start and so on.

And H represents heavy rain.

And there are plenty of other weather symbols as well.

Let's keep the bottom four displayed and introduce two more symbols, these ones here.

Compare these two new symbols with the ones at the bottom.

What's the same and what's different? In particular, when might you see these two new weather symbols? And which of the symbols in the bottom row might they replace? Pause video while you think all of this and press play when you're ready to continue together.

Well, the difference between these two new weather symbols and the ones at the bottom is rather than having the sun, we have the moon.

Therefore, these two new symbols are all about weather at night.

And then we can compare what's the same between these two new symbols and the ones at the bottom to see which ones they replace.

For example, the new symbol on the left represents clear sky at night.

It's a bit like when it's sunny and there are no clouds around.

But in night, there's no sun.

There's the moon instead.

The second weather symbol that has a cloud in it, just like sunny intervals does, so that is about clear sky intervals at night.

So sometimes it'll be clear sky and sometimes it won't.

Sometimes it'll be clouds.

These weather symbols will replace any symbol involving the sun if the forecast shows the weather at night.

A forecast is a prediction of a future event occurring, and this is done based on data.

Let's take the word forecast and break it up into parts: fore and cast.

The part that says fore, that represents the word before.

And cast represents plan.

Therefore, a weather forecast is a prediction of future weather conditions based on data collected on atmospheric conditions at the time, how those conditions are changing, as well as historical weather information too.

There are two common ways to see a weather forecast.

One is as a weather report.

It might look something a little bit like what you can see here.

The other is as a weather map, like what you can see here.

Let's use both of these and try to interpret them.

Let's start with a weather report.

Weather reports are a great way of assessing weather conditions in one location over a period of time, such as a whole day or across multiple days.

Different weather reports will give different levels of information, but you'll usually see something a bit like this.

We have different times of the day.

We have different conditions of the weather at each time of the day, and we have temperatures as well.

You may see other information as well, such as wind speeds or chance of rain or pollen levels and so on.

But this is a basic form how we're going to begin looking at.

A weather forecast will show the expected weather at a certain time.

For example, if you look at a table, you can see there is weather shown for midnight, 3:00 in the morning, 6:00 in the morning and so on.

But what if you want to know what the weather might be at a time that is not listed on that forecast? Hmm.

Well, weather conditions at any other time that are not in the forecast can be anything.

However it is usually one of the weather conditions at the time on the report, either just before or just after the time you're concerned with.

For example, the weather at 9:00 am is predicted to be sunny intervals, and the weather at 12:00 pm is rain showers.

So what does that mean? Well, it means that rain showers will begin sometime between 9:00 am and 12:00 pm.

So at 10:00 am, the weather will likely be either sunny intervals or rain showers because those are the two weathers that happen either side.

It's probably not going to be snow, based on the rest of what we can see there.

It could be, but probably not.

And in terms of temperature, at 9:00 am, the temperature is predicted to be 10 degrees Celsius and then at 12:00 pm, it's predicted to be 11 degrees Celsius.

So between 9:00 and 12:00, the temperature is going to increase from 10 degrees Celsius to 11 degrees Celsius.

Therefore at 10:00 am, we can predict that the temperature is going to be somewhere between those two temperatures, somewhere between 10 degrees Celsius and 11 degrees Celsius.

So let's check what we've learned.

You've got a weather forecast here.

Could you please use that information to complete the two sentences you can see on the screen? Pause while you do it and press play for answers.

Okay, let's take a look.

The temperature at 3:00 am will be 5 degrees Celsius and the temperature at 4:30 am is likely to be between 5 degrees Celsius and 9 degrees Celsius.

That is because at 3:00 am, it's predicted to be 5 degrees and at 6:00 am, it's predicted to be 9 degrees.

So between those two times, it's going to increase from 5 degrees to 9 degrees.

So at 4:30 am, we can predict that it's gotta be somewhere between those two temperatures.

It could be different, but it's likely to be between those two.

What are the weather conditions likely to be at 7:00 pm then? Pause while you write something down and press play when you're ready to see an answer.

So this time, we're not looking at the temperature, we're looking at the weather conditions.

That means it's likely to be either sunny or rain showers because those are the weather conditions on either side of 7:00 pm.

Between which two times is the sunrise? And explain how you know.

Pause while you write down your answer and press play when you're ready to see what the answer is.

The answer is between 6:00 am and 9:00 am.

And this is because at 6:00 am, the weather shows clear sky intervals without the sun.

While at 9:00 am, it shows clear sky intervals with the sun.

So we can expect that the sun is going to rise between those two times.

So now we've looked at weather forecasts, let's now take a look at weather maps.

Weather maps are a great way of assessing weather conditions across multiple locations at one point in time.

For example, here's a weather map for Oakfield at 3:00 pm or 1500 hours.

Different weather maps will give different levels of information, but you'll usually see weather conditions such as sunny or sunny intervals, and you'll usually see temperatures such as 19 degrees Celsius or 18 degrees Celsius and so on.

Weather maps can be used to compare weather conditions across a larger area and assess what sorts of trends might be present.

For example, in this weather map, we can see that the weather in Oakfield at 3:00 pm is warmer to the east and cooler to the west.

We can see that by looking at the temperatures.

For example, Oakfield Harbour is 19 degrees Celsius and Oakfield Old Town is 17 degrees Celsius and those are on the east.

But if you look towards the west, we have Oakfield Academy, which is 16 degrees Celsius, and Oakmoor, which is 15 degrees Celsius.

Those are cooler than the locations to the east.

We may also compare weather conditions.

For example, towards the north east of Oakfield, the weather is sunny.

However, towards the west of Oakfield, the weather is cloudy with rainfall.

So let's check what we've learned.

Here, we have three people all making statements about the weather in Oakfield.

But whose statements are correct? And there may be more than one correct one as well.

Pause the video while you write something down and press play when you're ready to see the answer.

Well, Aisha and Lucas are both making correct statements about the weather.

Aisha says there is rain in the north-east of Oakfield.

We can see that in Oakfield Harbour.

Lucas says the temperatures of south Oakfield are warmer than north Oakfield, and we can see that by looking at the temperatures.

In the south, we have 14 degrees for Oakmoor and 15 degrees Celsius for Oakfield Old Town.

But in the north, we have 13 degrees, 12 degrees, and 10 degrees Celsius for the locations in the north.

So yes, the temperatures are warmer in the south.

And then Laura says there is rain at Oakmoor.

Well, that is not true.

We can see that there are sunny intervals at Oakmoor.

So we have some more information now about temperatures at 3:00 pm, as well as a map on the left, which shows 5:00 pm.

Which locations show the greatest change of temperature from 3:00 pm to 5:00 pm? Pause while you write something down and press play for an answer.

The answer is Oakfield Harbour.

If we look at Oakfield Harbour, it changes from 19 degrees Celsius at 3:00 pm to 10 degrees Celsius at 5:00 pm and that means it's a change of a 9 degrees, which is more than any of the other changes we can see.

Oakfield Old Town had the largest decrease in temperature from 3:00 pm to 11:00 pm.

Could you please suggest a possible temperature at Oakfield Old Town at 11:00 pm? And there's more than one correct answer here.

Pause video while you do it and press play when you're ready for an answer.

Well, to solve this problem, it helps to break into small steps.

So to begin with, you can work out what is the temperature decrease for each of the locations from 3:00 pm to 11:00 pm? Well, we can see for Oakfield Academy, it decreases by 7 degrees.

For Oakmoor, it decreases by 8 degrees.

And for Oakfield Harbour, it decreases by 11 degrees, which means out of those three, Oakfield Harbour has the greatest decrease of 11 degrees.

But we're told that Oakfield Old Town has a greater decrease because it has the largest decrease in temperature.

That means the temperature in Oakfield Old Town must decrease by more than 11 degrees.

17 subtract 11 is 6, which means the temperature must be under 6 degrees Celsius.

So if you see anything that is under 6 degrees, the answer's correct.

For example, 5.

5 degrees Celsius or 2 degrees Celsius.

You could write something like -100 degrees and be technically correct from a mathematical point of view, but that wouldn't really be a realistic within the context.

It's helpful to have something that is still quite realistic and comparable to the other places around Oakfield.

Okay, it's over two for Task A.

This task includes three questions, and here is question one.

Question one, you need to interpret a weather map.

Pause while you do this and press play when you're ready for question two.

And here is question two, which involves interpreting a weather report.

Pause while you do this and press play when you're ready for question three.

And here is question three.

This involves both a weather map and a weather report.

Pause while you do this and press play when you are ready for some answers.

Okay, let's go through some answers.

For the question one, you had your weather map, and the context is at 8:00 am, Sophia cycles to Oakfield Academy from her house near Old Town and the route is shown with a dotted line.

And you need to decide which of the items Sophia should take on a journey based on the weather that is predicted.

Well, let's take a look at these.

Sophia should bring her raincoat, as she passes between two locations that show rainfall.

So yes, a raincoat would be quite good.

Sophia should also bring her scarf, as in locations with rainfall, the temperature drops below 10 degrees Celsius, so for example, at 8 degrees Celsius and 9 degrees Celsius in the two locations on either side of it.

However, Sophia does not need to bring her sunglasses as there are only sunny intervals at Oakfield Academy, and also where she starts as well.

This is not constant sun.

So if she takes her sunglasses, she could take them, but she has to be keep putting 'em on and taking 'em off again and putting 'em on, taking off again and so on.

So she might not want to take them.

And then in question two, based on this weather report, we can see that the sun is due to rise between 4:00 am and 6:00 am.

And in terms of trends in weather between 8:00 am and 12:00 pm, we can see that the rainfall is going to increase from just being showers to heavy rain.

And also, we'll see that the temperature will drop by 2 degrees.

It'll drop from 13 degrees Celsius to 11 degrees Celsius.

And we can also see that the mean temperature during nighttime hours is 9 degrees Celsius, which we get from adding together the three temperatures we know and divide them by three.

And then for part d, we could conclude that at 1:00 pm, the weather is likely to be either sunny intervals, rain showers, or heavy rain.

And then in question three, you had a weather report for a particular location in Oakfield, which can be seen on that map showing the weather at 6:00 pm.

The report must be for Oakmoor.

This is because both the report and the map show heavy rain and a temperature of 10 degrees Celsius at the same time, 6:00 pm.

And then in part c, you are told that the range of temperatures at location A on the map is the same as a range in the report location.

You had to work out, what was the maximum possible temperature you could have had at location A? And what was the minimum possible temperature you could have had at location A? Well, the warmest it could possibly be at location A is 20 degrees Celsius.

It would be that if we assumed that 12 degrees was the coolest temperature and the range was 8 degrees.

So the maximum, the warmest it would be, would be 20 degrees Celsius.

The coolest it could possibly be at location A based on this information will be 4 degrees Celsius.

There we've assumed that 12 degrees Celsius, at what we can see in the map there, is the warmest it got in location A.

And as the range was 8 degrees Celsius, that means the coolest could have been 4 degrees.

You're doing great so far.

Let's now move on to the next part of this lesson, where we're going to be analysing extra forecast information.

Here we have a weather map for Oakfield at 3:00 pm and we have Andeep.

Andeep says, "Is it really 16 degrees here at Oakfield Academy? It feels, oh, a lot colder than that." Hmm.

I wonder why Andeep thinks it's cooler than what it is.

Let's think about this.

The most common temperature shown on a weather forecast is the air temperature.

So the 16 degrees Celsius at Oakfield Academy shows only the temperature of the outside air at 3:00 pm.

What other weather factors could make the temperature feel colder than 16 degrees to Andeep? Hmm.

Perhaps pause a video while you think about this and press play when you're ready to continue.

Well, the difference between the air temperature, which is 16 degrees Celsius and what the temperature actually feels like can be due to quite a few different factors.

One is the rainfall.

The rainfall can make it feel cooler than what it is.

Or wind speeds, or wind direction, or air pressure, or humidity.

Any of these things can make the temperature feel different to what the air temperature is at that particular time.

Andeep says that "feels like" temperature at Oakfield Academy might be lower than what is reported on the map due to cold rain and winds.

And this phrase "feels like" temperature is something that is often reported in weather forecasts.

Even though the air temperature at Oakfield Academy is 16 degrees Celsius, it feels closer to 12 degrees Celsius due to the amount of cold rain and winds.

So here we have a basic weather report that shows only weather conditions and temperatures and they are the air temperatures.

But both our weather map and our weather report can show extra information that gives more context about the weather conditions.

This extra information can help explain the difference between air temperature and the "feels like" temperature at any given time.

It could look something a bit like this.

We have the wind speeds in kilometres per hour and we have the wind direction as well.

This provides a little bit more information that might help us decide what the weather is going to feel like.

Yes, it might be warm in terms of air temperature, but it might also be very, very windy as well, and rainy, which can make it not feel like a warm day.

So we also have this "feels like" temperature often reported as well.

Sometimes, an increase in wind speed may make a temperature feel colder.

On this particular weather report, an increase in wind speed from 10 kilometres per hour to 16 kilometres per hour, drops the "feel like" temperature by 2 degrees even though the air temperature is predicted to stay the same.

Furthermore, wind from a south-westerly direction seems to have no influence on temperatures whilst wind from a northerly direction seems to reduce the "feels like" temperature.

So let's check what we've learned.

Here, you've got a weather report.

At which time of day does the wind cause the greatest difference between the air temperature and the "feels like" temperature? Pause while you work this out and press play when you're ready for an answer.

Well, we can work this out by calculating the difference between the air temperature and the "feels like" temperature for each of those times and see which one has the greatest difference.

If you did that, you would find it at 3:00 pm.

The air temperature at 3:00 pm is 16 degrees Celsius, but that strong wind makes it feel like 10 degrees Celsius, so it feels six degrees cooler than what the air is.

So which of the two wind directions in this weather report appears to have the most influence on the "feels like" temperature? Pause the video while you write something down and press play when you're ready to see what the answer is.

Based on this information we can see, we can conclude that easterly winds or winds from the east has the greatest effect on the "feels like" temperature.

We can see each time there's an easterly wind, the "feels like" temperature is lower than the air temperature.

Whereas if you look at the times when the winds come from the south-west, most of them have the same temperature for air temperature and "feels like" temperature or they might be different but only by 1 degree.

Let's now think about something else that affects weather conditions, and that is air pressure.

Air pressures of different densities can also influence weather conditions and we often see 'em on weather maps, looking something like this.

A blue line with triangles shows a cold front and the direction that the triangles point in, show the direction of the dominant cold air that leads to colder temperatures and rainfall.

For example, on this weather map, we have six locations marked, three on either side of that blue line, which shows the cold front.

Can you guess which locations will have a cooler temperature than the others? Well, it would look something a bit like this.

The locations that are on the north-east side of that blue line, those are the ones that the arrows are pointing towards, so that's where the cooler temperature is.

We can see those temperatures are 13 degrees, 9 degrees, and 12 degrees, and it's raining there as well.

Whereas the locations on the other side of the blue line, which is not the way that the triangles are pointing, those locations are warmer, 17 degrees, 16 degrees, and 18 degrees.

They are all sunny.

They're cloud, but all sunny and not raining.

Now locations influenced by cold fronts are more likely to result in rain.

The percentage chance of rainfall can also be shown on a weather map and on a weather report.

It might look something a bit like this on a weather map.

It tells you a percentage.

That percentage is the chance that it might rain or the probability that it might rain at that time.

A warm weather front is shown by a red line with semicircles and the direction the semicircles point in, show the direction of the dominant warm air that leads to hotter temperatures and clearer skies.

For example, it might look something a bit like this.

Once again, we have six locations marked on this map.

Can you guess which ones will be warmer than others? Well, the locations at the top where the semicircle are pointing towards, those ones are warmer than the ones on the other side of the line.

So let's check what we've learned.

Here, we have a web map which shows the percentage chance of rainfall in three different locations.

Could you please write down suitable values for a and b? There's no definite right or wrong answer here, but think about how those two values will compare with each other.

Pause video while you do that and press play when you're ready for an answer.

A should be around 65%.

It may not be exactly 65%, but it should be around 65% because it's similar to the next nearest location on the same side of that weather front.

Whilst b should be a lot lower than 65% because it's on the other side of the weather front.

Here's the weather map again with a different weather front shown.

Which of these locations is likely to have a temperature of 25 degrees Celsius? Pause while you choose from a, b, c, or d and press play when you're ready for an answer.

The answer is a, Oakfield Academy.

Out of those four locations, that is the only one, which is on the same side of the weather front as the point marked 23 degrees.

So that one is likely to be similar in temperature to the 23 degrees, whereas all the others are on the other side of the weather front.

They're on the cooler side, so we probably expect those to be cooler.

Okay, it's over to you for Task B.

This task has three questions and here is question one.

Pause while you do it and press play for question two.

Here is question two, which has parts a, b, and c.

At the moment, you can see part a, pause while you do it and press play when you're ready for the other two parts.

And here are parts b and c of question two.

Pause while do this and press play for question three.

And here is question three.

Pause while you do this and press play when you're ready for some answers.

Okay, let's go through some answers.

For question 1a, You should have written that southerly winds or winds from the south result in the least difference between air temperature and "feels like" temperature.

The maximum case we can see is a difference of 1 degrees.

And you should have written that easterly winds or winds from the east result in the most difference between air temperature and "feels like" temperature.

The maximum case we can see here is a 4-degree difference between the two.

For b, here's an answer.

The cold front likely blew over Oakfield Harbour between 12:00 pm and 3:00 pm and this is because the weather conditions went from sunny intervals to heavy rain and the temperature started to drop significantly starting from this particular timeframe.

Then question two, for part a, you may have written that the greatest difference was on the 1st of July at 2:00 pm, and the "feels like" temperature was three degrees higher than the air temperature.

For b, higher humidity likely leads to an increase in "feels like" temperature compared to air temperature.

And for part c, the evaporation of rainfall due to high temperatures might result in higher humidity.

And then in question three, you had to use the information given on the weather map and the weather report to make a sensible prediction for the missing details in the weather conditions at 4:00 pm at Oakmoor, and you have to write a sentence to justify your prediction.

Let's think about what information may inform our prediction.

If we look at the weather map, we can see that there is a cold front and the triangles point towards the north east.

So at 12:00, we can assume that the temperature in Oakfield Harbour is likely to be colder than in Oakfield Academy, Oakfield Old Town and Oakmoor.

If we look at the weather report, take a look at which direction the wind is blowing.

It is a north-easterly wind, which is going to blow that cold air front to the southwest, dragging the cold air with it, and that will also increase the likelihood of rain.

And if it rains, it may feel cooler than what the air temperature actually is.

So we may fill in the missing details with some information that might be a bit like this.

It may not be these exact same numbers, but it's the comparisons that are important to show you understood what has been shown in the information.

For example, as that cold weather front moves to the southwest, the air temperature is likely to get cooler, so the air temperature at 4:00 is going to be lower than it was at 12:00.

Here, we've put 6 degrees Celsius, but you may have written something different, but hopefully it is cooler than 11 degrees Celsius.

The chance of rain has increased from 20% to 80%.

You may have put something different to 80%, but hopefully you've put something that shows it's likely to rain, it's greater than 50%, for example.

And because it's raining or it's likely to rain, we may put that the "feels like" temperature is cooler than whatever we put for our air temperature.

In this case, we put the air temperature with 6 degrees, so we put the feels like temperature as 3 degrees, because 3 is less than 6.

Our sentence to describe why is the front.

The wind direction is likely to blow the cold front across Oakmoor.

The cold front will reduce the air temperature and increase the chance of rainfall.

Due to the stronger winds and the greater chance of rain, the "feels like" temperature may also drop further as well.

Well done today.

Let's summarise what we've learned.

A weather forecast can be shown on a weather map or on a weather report.

There are benefits to both of these representations.

Different weather conditions can be represented using different icons.

A basic weather forecast usually shows the weather conditions and the air temperature.

However, you can get more complex weather forecasts, which may also show wind speed, wind direction, cold and warm fronts, percentage chance of rainfall, or humidity levels, and other information as well.

These other weather data factors may influence how different the temperature feels in comparison to the air temperature.

Well done today.

Have a great day.