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Sources: BBC, National Weather Services, Intellicast, Space Science and Engineering Center, the Met Office, Yahoo! Weather
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TODAY’S HEADLINES
TODAY’S EXTREMES
Hottest: Pretoria Boys’ High School, South Africa, 34.2°C
Coldest: James Gibbons School, Edmonton, Alberta, Canada, -24.0°C
Windiest: Richard Lander School, Truro, Cornwall, UK; Norwich School, UK; St Patrick’s Primary School, near Preston, Lancashire, UK: all 67 km/h
Driest: Pasadena City College, California, USA, relative humidity 19%
Wettest: Jakarta International School, Indonesia, 74.3 mm of rain
TODAY’S REVIEW OF METLINK OBSERVATIONS
Have you looked at today’s weathercams? If not, click here.
To view today’s observations in the database, click here.
To find out how your observations compare with the average for January, click here.
AUSTRALASIA
A major storm brought very heavy rain to Jakarta overnight. Relative humidity at the Jakarta International School at 00:00 GMT (7 am Local Time) 100%, with a temperature of 24°C and no wind. Definitely hot and humid! Hot and humid at Singapore, too, with a temperature of 27°C at 06:30 GMT (2.30 pm Local Time) and a relative humidity of 83%. Drizzle falling and the sky completely cloud-covered. Cool and clear at Keio in Japan, with a temperature of 11.6°C at 01:20 GMT (10.20 am Local Time) and a low relative humidity (35%).
AFRICA AND ASCENSION
Hot at Two Boats School on Ascension today, with a temperature of 26°C at 12:30 GMT (12.30 pm Local Time). A breeze of 15 km/h from the north-east and rather a lot of cloud (cumulus and cumulonimbus). "Dull and cloudy with a light shower" reported the students. "Cloudy and clammy but fairly mild" was the comment from Kampala, Uganda, where the temperature at 10:00 GMT (1 pm Local Time) was 26°C and the cloud amount 8 oktas (altostratus cloud). Calm and cloudless with a temperature of 19.5°C at Bulawayo in Zimbabwe at 05:30 GMT (7.30 am Local Time). Rather similar at Marondera in Zimbabwe, where the temperature at 06:00 GMT (8 am Local Time) was 21.3°C and the sky almost cloudless (just one okta of cirrus). Still hot in Pretoria, with temperatures rising above 30°C, but cloudier than in recent days, with cumulus and stratocumulus reported. Cloudy, warm and humid, too, at Highbury Preparatory School in KwaZulu Natal, where the temperature at 05:00 GMT (7 am Local Time) was 23°C, the relative humidity 91% and the cloud cover 8 oktas of stratocumulus and altostratus. Here, the students were hoping for an end to a spell of dry weather. Hot and sunny at Kgaswe Primary School, Botswana, where there was a light breeze to bring some relief from the heat. The temperature at 09:00 GMT (11 am Local Time) was 30°C.
Cyclone Dina was today west of Mauritius and Réunion and continuing to head towards Madagascar.
EUROPE
Wet and windy today in many parts of the British Isles, with wind speeds of 67 km/h reported from Norfolk, Cornwall and Lancashire. "Totally cloudy, windy and wet" commented the students of the Richard Lander School at Truro in Cornwall. "Cloudy, dull and chilly with a strong breeze with big puddles" was the comment from Edgbaston High School for Girls in Birmingham. "Horrible day; wet weather this morning; gusty variable wind" was the comment from Bradfield College in Berkshire. "Cold and wet" at Norwich High School for Girls. "Horrible" at St Oswald’s Primary School in Sheffield. "Cloudy, windy and cold" at Chaldon Primary School in Surrey. No better at Coed Cae Junior School in south-east Wales, where it was "a dark gloomy day with low cloud covering the valley tops". At the Lionel School on the Isle of Lewis in the north-west of Scotland, the weather was "becoming colder as the wind veered to NE with rain". At Portgordon Primary School in Morayshire, the weather was "dull and wet". At Farr High School on the north coast of Scotland, it was "cold, damp, cloudy and windy". Was the weather any better in Ireland? Overcast at the Malahide Community School in Dublin. "Heavy rain and dark skies" at Ennis, County Clare. Overcast with slight drizzle falling in Galway. At least frost was not a problem anywhere in the British Isles today, with temperatures well above freezing point in most places and over 10°C in some. And there was a rainbow at Pinewood School near Swindon when the sun put in an appearance this morning.
Wet and windy in Madrid, too, today. Still quite warm and pleasant in Toulouse, though, with a temperature of 11.0°C at 11:00 GMT (12 noon Local Time). "Sunny and crisp" in Bavaria, where the temperature was only +1°C at 08:10 GMT (9.10 am Local Time). Warmer elsewhere in Germany, though, with a temperature of 8.3°C at 09:30 GMT (10.30 am Local Time) at Geilenkirchen. Still quite mild in Strasbourg, with temperatures several degrees above freezing point, but drizzle set in later in the day after a nice morning. Warm and quite sunny in Malta, but the fresh breeze made the weather feel a bit chilly. Overcast with a temperature several degrees above freezing in Bozen, northern Italy. Warm for the time of year (about 7°C) in Constanta, Romania.
Still cold in Finland, with snow reported from all of the MetLink schools and temperatures well below freezing. Much warmer in southern Sweden, where, at Bor School, the temperature at 07:00 GMT (8 am Local Time) was 4.2°C. The weather was "wet and dull", though, with slight rain falling at the time of the observation. Cloudy with slight snow falling in Oslo.
For a chart showing temperatures, significant weather and distributions of barometric pressure over Europe at 12:00 GMT today, click here.
NORTH AMERICA
Sunny and warm in California, with a temperature of 20°C at Mendenhall Middle School in Livermore at 21:00 GMT (1 pm Local Time) and a temperature of 14°C at 19:27 GMT (11.27 am Local Time) at Pasadena. A bit cooler (10.8°C) and breezy at 18:37 GMT (10.37 am Local Time) at Cantara Street Elementary School in Reseda, California, but at least the weather was sunny. Cloudy with a temperature only just above freezing (2.8°C) at Moses Lake at 19:00 GMT (11 am Local Time). "Clear and cold" with a temperature of —1°C at Fernley in Nevada at 17:10 GMT (9.10 am Local Time). "A very foggy day with drizzle falling" and a temperature of 8°Cat 18:30 GMT (12.30 pm Local Time) at the Frank Hall Elementary School in Aurora, Illinois. Only 4°C and quite breezy at Raleigh in North Carolina at 13:57 GMT (8.57 am Local Time), with steady rain falling.
Quite a lot of
unpleasant weather today. Where would you have gone had you been able
to visit any MetLink location in the world, basing your choice solely
on the weather at that place? Where has the weather caused any
problems for car drivers? How do the Scandinavians and the Canadians
cope with the cold weather? How do people in low latitudes cope with
hot and humid weather?
TODAY’S ANALYSIS
NB On the so-called ‘visible images’ from satellites, what you see is more or less what you would see with your own eyes if you were in the satellite and looking in black and white. On the so-called ‘infra-red images’, the whitest areas are the coldest and the blackest the hottest. Thus, high clouds show as white areas. Medium-level clouds and very cold land areas show as grey. For information about obtaining satellite images of the highest quality, see the Notes section below.
AUSTRALASIA
Today’s satellite
images of the western Pacific
and Australia show that cold air was flowing out from eastern Asia
and becoming convectively unstable when it flowed across the warmer
sea towards Japan. When it first reached the sea, the air remained
free of cloud, hence the clear skies just off the coast. The farther
the air flowed over the sea, however, the more it was warmed and
moistened, until it became convectively unstable. Then, cumulus
clouds started to form. These are shown as speckled areas on the
satellite image. Cumulus clouds often form into lines, called
‘cloud streets’. Cumulonimbus clouds tend to group into
cells or clusters of clouds.
The front that lay over eastern Australia yesterday had continued to
move eastward and weaken. Indeed, it had become so weak today that it
was not shown on today’s
weather chart. The
‘visible’
satellite image shows that
cumulus clouds were present over much of Australia today. This image
shows the situation at 06:00 GMT, i.e. the middle of the afternoon
over Australia. The cumulus clouds would die away during the night,
when surface temperatures fell. An interesting phenomenon that can be
seen on this satellite image is the sun’s reflection off the sea
north-west of Australia. The satellite is geostationary and is
positioned over the equator at about 140°E at an altitude of
almost 36,000 km. The sun is overhead at about 19.5°S right now.
Is the location of the sun’s reflection consistent with this?
When pondering this question, remember that the sun is overhead at
90°E at 06:00 GMT.
When studying the weather
chart for Australia, remember
that winds blow clockwise around Lows in the southern hemisphere,
anticlockwise around Highs.
INDONESIA AND SOUTHERN ASIA
The world satellite composite from Wisconsin shows the Intertropical Convergence Zone (ITCZ) running across the Indian Ocean from Africa to Indonesia and beyond, with largely clear skies over India. Notice how patchy and variable the ITCZ was today. It was very weak over the Atlantic Ocean but very active over Indonesia. The ITCZ consists of clusters of cumulonimbus clouds which rise to heights of 15 km or more. Heavy rain falls from these clouds. The visible and infra-red images from the geostationary satellite over the Indian Ocean reveal the ITCZ’s patchy features very clearly. Notice how wide the ITCZ is. It really is a zone. These two images show Cyclone Dina very clearly, just to the east of Madagascar. The visible image also shows the snow-covered Himalayas very clearly. You can see the Indus Valley, too, if you have a good enough computer screen. The infra-red image shows that the ground was very warm in India and Arabia. The satellite image was obtained at 08:00 GMT, which is midday to early afternoon over the areas in question. Remember that hot areas appear dark on infra-red images, cold areas white.
AFRICA
Today’s weather chart from the South African Weather Bureau again shows many depressions and fronts over the Southern Ocean between the parallels of 40°S and 60°S. It also shows Cyclone Dina to the east of Madagascar. A subtropical anticyclone cell (1025 mb) was centred to the south-west of Cape Town and another (1022 mb) was centred near Amsterdam Island (37°30’S 77°30’E). Pressure was low over South Africa and a weak front lay off the south coast of South Africa. The visible satellite image of Africa shows that ITCZ cloud covered most of central and southern Africa from about 5°N to about 15°S. Patches of cumulus and cumulonimbus clouds can be seen over the Atlantic Ocean near Ascension Island. Notice the Zaïre River just north of the equator near 20°E and notice, too, the River Nile. How many more surface features can you find on this superb satellite image? Tibesti Mountains?
For close-up satellite images of Cyclone Dina, click here or here. This cyclone has begun to weaken, but is still capable of causing havoc. Even when they are past their most intense, tropical cyclones produce not only strong winds but also torrential rain and, therefore, severe flooding.
EUROPE
Today’s weather chart shows that fronts and isobars were plentiful over north-west Europe and the north-east Atlantic today. A complex and active depression was centred over Ireland, and fronts from it brought rain and drizzle to all parts of the British Isles and to many parts of France, Spain, the Low Countries, Denmark and southern Sweden. Visible and infra-red satellite images showed the clouds of the fronts very clearly. Notice that the cold front of the depression over Ireland extended right across Spain to Madeira. As today’s observations show, winds were quite strong and squally over many parts of the British Isles. The main problem of a practical nature occurred where roads were wet, the risk there being aquaplaning. Over Ireland, which was near the centre of the depression, winds were quite light, as the chart of observations at 12:00 GMT shows. The circulation around the depression can be seen clearly on this chart, with winds from the east over northern Scotland and south over most of England. On this chart, air temperature is the figure top left of the station circle. The barometric pressure change in the past three hours is the figure to the bottom right of the station circle. The figure top right is barometric pressure in tenths of a millibar. Put a 9 or 10 in front of the figure to obtain the value in mb. Thus, the pressure value at Cherbourg is 990.0 mb. Wind speeds and directions over the Atlantic at 50°10’N 6°10’W are shown in the table of observations made at this buoy from 16:00 GMT yesterday to 14:00 GMT today. Speeds reached gale force around midnight GMT last night. To inspect observations from buoys on the Atlantic near the British Isles, click here.
A depression to the east of Finland fed cold air over northern Scandinavia. For a chart showing temperatures over this part of the world, click here. As this chart shows, temperatures were below —20°C at 12:00 GMT today. For a graphic picture of temperature contrasts and significant weather across Europe today, click here. The areas of rain and showers can be seen clearly (showers being shown as upside down triangles). Fog occurred over central and eastern Europe.
NORTH AMERICA
Today’s weather chart and satellite imagery show that fronts brought precipitation to many parts of central and eastern parts of North America today, with high pressure bringing clear skies in many parts of the west. High pressure lay over central Canada. For charts of weather observations at 12:00 GMT today over south-western parts of the USA, click here. For charts of the Pacific north-west at12:00 GMT today, click here. Please note that 12:00 GMT corresponds to 4 am in California, Oregon and Washington State, so it is not surprising that the temperatures on these charts are quite low (well below 0°C in many places). For the latest weather chart showing isobars over North America, click here. For the latest weather chart for Canada, start from here. Please note that these charts will be current at the time you obtain them. They will not be charts for 23 January.
NOTES
You can obtain satellite images of the highest quality from the Dundee Satellite Receiving Station, Dundee University, Scotland. First, though, you must complete an on-line registration form. Registration is free and the images are free. Do not hesitate to register. The staff at Dundee welcome new users and you gain access to images of very high quality. You go first to http://www.sat.dundee.ac.uk/ and click on the button labelled "Register for free images". All you do then is fill in the form, press the button labelled "Create account", remember the user name and password you chose and start using the site.
From the satellite station’s home page, i.e. http://www.sat.dundee.ac.uk/, you click on "Home for registered users" and then choose the images you require. I suggest you begin with "Geostationary satellite images — view the whole earth". On this page, which provides links to the latest images from geostationary satellites, you select whichever image you require. If you want an image from a previous day, choose "Archive".
Images from the following satellites are available: METEOSAT (which covers Europe and Africa), Japanese GMS (which covers the western part of the Pacific, Australia and Indonesia), US GOES-EAST (which covers North and South America), US GOES-WEST (which covers the eastern Pacific) and IODC (which covers central Asia, southern Asia and the Indian Ocean).
From all of these satellites, images can be obtained in Visible and Infra-Red formats. From METEOSAT and IODC, images showing distributions of water vapour can be obtained. From METEOSAT, colour-enhanced images of Europe can be obtained.
If you wish to view images from polar-orbiting satellites covering western Europe and the eastern Atlantic from Greenland and northern Scandinavia to western Asia and North Africa, go from "Home for registered users" to AVHRR Images — latest images or, for archived images, AVHRR Images- Archive.
OTHER NOTES
A school weather site that might be of interest to you is that made available by Scalloway School, Shetland, UK.
If you require information about climate on the web, click here. If you seek climatological data, click here or here.