Wednesday, November 21, 2007

Traditional weather forecasting - Interesting

Traditional Methods
Wherever humans have settled around the world, being able to predict the weather has been an advantage. Most activities are closely linked to the weather, and communities often have a store of local weather knowledge or lore, often in the form of rhymes and mottos.

A favourite of traditional forecasters, pine cones open and close according to the humidity of the air. An open cone is supposed to mean dry weather and a closed cone indicates damp weather.

Seaweed and other marine algae also respond to changes in humidity. If the humidity is low, it is more likely to be dry the next day - dry seaweed indicates dry weather.

Can poems forecast the weather?
Oak and ash trees are deciduous trees which lose their leaves in winter. In Britain, supposedly if the ash tree has leaves first then it will be a summer of rain; if it is the oak tree first then it will be a fine summer instead. There is a rhyme for this:

Ash leaf before the oak, then we shall have a summer soak; Oak leaf before the ash, the summer comes with nary a splash

Another favourite is the poem:

Red sky at night, shepherd's delight / Red sky in the morning, shepherd's warning

The redness of the sky depends on the amount of dust particles in the air. In Britain, where weather comes from the west, a red sunset suggests that dry weather is approaching.

Such lore is based on years of observation and may sometimes be correct. However, it is likely to be wrong as often as it it right.

Clear sky to start...

At this time(9:03AM) yesterday it was raining heavily, but today at this time it's CLEAR with some thin clouds around. It's like again the North-East has been switched off...mmm
Chennai recorded around 6CM of rain in the past 24hrs.
Here is the latest forecast meteogram for Chennai...

Now here's our forecast for the day, The day will be partly cloudy, mild and high in humidity. Chance of light showers around mid-morning or in the evening.
The rain rate will go down, going by the meteogram.