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Click on today's infra-red satellite images below for full size version (images: Nottingham Univ)
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At my home near Reading this morning, there was a beautiful sunrise. For several minutes, the cirrus and altocumulus clouds put on a show. Orange, red, pink: all these colours were seen. I enjoyed the spectacle, but then my thoughts turned to the old saying:
Red sky at night, shepherd's delight
Red sky in the morning, shepherd's warning
and the seafarer's equivalent:
Red sky at night, sailor's delight
Red sky in the morning, sailor's warning
Was the weather too nice to last? Yes, it was! After the fine day yesterday, we had cloud and rain today. By 9 o'clock, there was an overcast of stratocumulus cloud. By mid-afternoon, light rain was falling. A weak warm front had arrived.
Until last century, when state meteorological services started to issue weather forecasts, shepherds, farmers, sailors and, indeed, all whose livelihoods depended on the weather relied upon weather lore. They observed cloud movements, the appearance of the sky, changes in wind direction and other changes in the weather. They studied the behaviour of plants, insects, birds and animals. They embodied their weather wisdom in the form of rhymes, jingles and proverbs. Some of their sayings are fairly reliable, but many are not. If you would like to learn more about weather lore, visit NOAA's Classroom@ Sea, the Weather Lore and Proverbs compilation by David Phillips of Environment Canada and the Weather Proverbs and Folklore page provided by Project Atmosphere Australia.
Wherever you go in the world, you will find weather lore. To what extent did the weather you experienced today conform to the earlier appearance of the sky, behaviour of animals, etc? PLEASE TELL US. In Australia, for example, did you have any signs that led you to expect the temperature to exceed 40°C today? Southmoor reported a maximum of 42°C today, and a number of places in Victoria exceeded even that temperature, reaching 43°C. To us in the UK, that is REALLY hot. We have never recorded a temperature higher than 37.5°C. How do people cope with extreme heat? Will someone from a part of the world that experiences very high temperatures, please tell us.
Today at Melbourne International Airport, not far away from Southmoor Primary School, there was an interesting sequence of temperatures, wind speeds and wind directions, as the following table shows:
|
TIME |
Noon |
1 pm |
2 pm |
3 pm |
4 pm |
5 pm |
6 pm |
7 pm |
8 pm |
|
TEMP |
35°C |
35°C |
37°C |
38°C |
38°C |
28°C |
23°C |
23°C |
22°C |
|
WIND |
N |
N |
N |
N |
N |
S |
SSW |
SSW |
S |
|
(mph) |
31 |
25 |
17 |
20 |
14 |
17 |
13 |
14 |
10 |
Notice the sudden change in wind direction and the corresponding fall in temperature. The cause is not obvious from the weather map. Pressure was high (1020 mb) immediately to the south of Melbourne, and another High (1028 mb) lay between south-eastern Australia and New Zealand's North Island. A trough of low pressure extended to northern Victoria from central Australia. Possibly a sea breeze set in between 4 and 5 pm, bringing cooler, moister air from over the sea which lies not far to the south of Melbourne.
Elsewhere today, there has been warm weather again at the MetLink schools in Africa, Oman, Ascension and India. As the CTOT and DTOT Meteosat images show and MetLink observations confirm, skies were clear of all but very small amounts of cloud over Ascension, Uganda and Ethiopia, but Zambia, Zimbabwe and eastern South Africa had a lot of cloud. Indeed, some precipitation fell. There were many shower clouds over Zambia and Zimbabwe and a well-marked depression was centred over southern Mozambique.
They weren't much impressed by the weather at Gabriel Pereira, it seems from their report of "Fog, cold day, we can't see our noses!!" Across Iberia in Tarragona, however, there was fine weather, and in Cyprus there was sunshine this morning. Across the central Mediterranean, however, satellite images show there was quite a lot of cloud, some of it associated with a Low not far north of our MetLink school in Malta. In Malta itself, winds today were from west or north-west and the temperature was in the range 13-15°C.
In Scandinavia, the weather was cool by most people's standards, but not exceptionally so for that part of the world. Winds were generally from the north-west, as a ridge of high pressure lay to the west of Norway. At Vörå, the temperature was well below freezing (minimum -15.1°C). At Bor, Sweden, the temperature rose above freezing point. It's all very different from this time last year, when temperatures fell to below -25°C over many parts of Scandinavia.
In Canada, at Edmonton, temperatures have also been low, falling to -18°C at Edmonton International Airport early in the morning. Today, pressure has been high over the Rockies, low over the Great Lakes and over the ocean east of Newfoundland, and high over the eastern side of Hudson Bay. The lowest temperatures to be found on the 0600 UTC weather chart for Canada was -31°C in northern Labrador.
What will tomorrow bring? According to the forecasters, the wind will blow from the west over the British Isles and fronts will bring rain to some places, especially Scotland. A deep Low is expected to bring rain and strong winds to northern and central parts of Norway and Sweden. Will the forecast be correct?
Pride of place today must go to Southmoor Primary School, Victoria, Australia, the first MetLink school ever to report a temperature of 40°C. What a scorching day they must have had! The temperature reached 42°C, but even this was not quite the highest temperature in Victoria, as several places in the State touched 43°C. How do people cope with extreme heat? Will someone from a part of the world that experiences very high temperatures, please tell us.
Today at Melbourne International Airport, not far away from Southmoor Primary School, there was an interesting sequence of temperatures, wind speeds and wind directions, as the following table shows:
|
TIME |
Noon |
1 pm |
2 pm |
3 pm |
4 pm |
5 pm |
6 pm |
7 pm |
8 pm |
|
TEMP |
35°C |
35°C |
37°C |
38°C |
38°C |
28°C |
23°C |
23°C |
22°C |
|
WIND |
N |
N |
N |
N |
N |
S |
SSW |
SSW |
S |
|
(mph) |
31 |
25 |
17 |
20 |
14 |
17 |
13 |
14 |
10 |
Notice the sudden change in wind direction between 4 and 5 pm and the corresponding fall in temperature. The cause is not obvious from the weather map. Pressure was high (1020 mb) immediately to the south of Melbourne, while another High (1028 mb) lay between south-eastern Australia and New Zealand's North Island. A trough of low pressure extended to northern Victoria from central Australia. Possibly a sea breeze arrived between 4 and 5 pm, bringing cooler, moister air from over the sea, which is not far to the south of Melbourne.
Notice also that winds from the north in Victoria bring hot weather. In Europe, we are accustomed to northerly winds bringing low temperatures. So says the saying: "The north wind doth blow, and we shall have snow"!
And talking of weather sayings, I was reminded of the "red sky in the morning, shepherd's (sailor's) warning" weather lore early this morning when the clouds turned lovely shades of orange, red and pink at my home near Reading. By 9 am, we had a sheet of stratocumulus cloud. By mid-afternoon, light rain was falling. A weak warm front had arrived. The aforementioned lore is fairly reliable, but many weather proverbs are not. If you would like to learn more about weather lore, visit NOAA's Classroom@ Sea, the Weather Lore and Proverbs compilation by David Phillips of Environment Canada and the Weather Proverbs and Folklore page provided by Project Atmosphere Australia. Wherever you go in the world, you find weather lore. To what extent did the weather you experienced today conform to the earlier appearance of the sky, behaviour of animals, etc? PLEASE TELL US.
In contrast to the heat of south-east Australia, the weather was colder today in central Finland than in recent days, and it was cold, too, in Edmonton, where the temperature at the International Airport fell to -18°C. Today, pressure has been high over the Rockies, low over the Great Lakes, low over the ocean north-east of Newfoundland, and high over the eastern side of Hudson Bay. The lowest temperature to be found on the 0600 UTC weather chart for Canada was -31°C in northern Labrador.
But MetLinkInternational is not just about extremes of weather and the reasons for them. It's also about normal weather, and there's been plenty of that around the MetLink world today. As the CTOT and DTOT Meteosat images show, the extent of, and intensity of, the Intertropical Convergence Zone (ITCZ) was today well within the 'normal' classification. Over the Atlantic Ocean, however, the ITCZ was less active than normal. The MetLink schools in southern Africa today had a lot of cloud and some precipitation. There were many shower clouds over Zambia and Zimbabwe and a depression was centred over southern Mozambique.
If you are looking for a student exercise that focuses on the ITCZ, look no further than here. This exercise contains links to a number of ITCZ websites.
In Uganda and Ethiopia, to the north of the ITCZ, the weather was again warm and sunny. At Ascension Island and in Bombay and Oman, too, the weather was also very warm and generally sunny. At this time of year, these locations are dominated by subtropical anticyclones.
They weren't much impressed by the weather at Gabriel Pereira, it seems from their report of "Fog, cold day, we can't see our noses!!" Across Iberia in Tarragona, however, there was fine weather, and in Cyprus the sun shone and the skies were clear this morning. Once again, the dominant influence in Cyprus was a ridge of high pressure extending westwards across Turkey. Over the central Mediterranean, however, satellite images show there was quite a lot of cloud, some of it associated with a Low over southern Italy, not far north of our MetLink school in Malta. In Malta itself, winds today were from west or north-west and the temperature was in the range 13-15°C.
In Scandinavia, the weather was cool by most people's standards, but not exceptionally so for that part of the world. Winds were generally from the north-west, with a ridge of high pressure to the west of Norway. At Vörå, the temperature was well below freezing (minimum -15.1°C). At Bor, Sweden, the temperature rose above freezing point. It's all very different from this time last year, when temperatures fell to below -25°C over many parts of Scandinavia.
As the weather chart for north-west Europe and adjacent parts of the North Atlantic Ocean shows, an anticyclone (central pressure 1039 mb) lay over the Bay of Biscay. At the same time, areas of low pressure were situated north-east of Newfoundland and over Iceland. Most places in the British Isles had some rain today, and Farr High School, the most northerly MetLink school in the UK, once again had a windy day, this time with wintry showers.
What will tomorrow bring? According to the forecasters, the wind will blow from the west over the British Isles and fronts will bring rain to some places, especially Scotland. A deep Low is expected to bring rain and strong winds to northern and central parts of Norway and Sweden. Pressure is expected to be high all the way from Portugal to the Czech Republic.
