How can I differentiate between monsoon rains and cyclonic rain?

[Hall]

In my country, we get yearly rainfall from South-West Monsoon. But from time to time, there is something called cylonic (or western) disturbances which bring rain in my country. I have myself observed that though disturbances are cylconic, yet we (at my particular location and about 50km radius) get just rain, no high speed winds.

I want to ask, how can I know, if it is raining today, whether the rain is from monsoon winds or from cyclonic disturbances?

 

[Baluncore]

It will depend on where you are. Take a look at the bigger picture by going to ...
https://earth.nullschool.net/#curre...a/winkel3=-276.82,13.17,618/loc=98.520,10.458
Click "Earth" to access the different parameters available. Find those that differentiate the circulation of a cyclone from the monsoon pattern. For example, the pressure altitude that best identifies the cyclones. After watching for a year, you should have found a reliable method. Let us know how you get on.

 

[anorlunda]

From a local weather station, the wind direction should change as a cyclone passes by. Monsoon winds, should tend to blow from the same direction hour after hour.

 

[Baluncore]

There should be a drop in the barometer as a cyclone approaches, followed by a rise as the cyclone moves away. The barometric pressure should be fairly stable during the monsoon.

 

[Vanadium 50]

A rain by any other name would feel as wet.

 

[Baluncore]

A rain by any other name would feel as wet.

“He makes his sun rise on people whether they are good or evil. He let's rain fall on them whether they are just or unjust.” ― Matthew 5:45

“The rain it raineth on the just. And also on the unjust fella;
But chiefly on the just, because. The unjust hath the just's umbrella.” ― Charles Bowen.

 

[willem2]

6 km (850 hpa),

850 hpa is not at an altitude of 6 km. air pressure is about 1000hpa at 0m, and about 850 hpa at 1.5 km.

 

[Hall]

I met a fatal failure.

 

[Hall]

It will depend on where you are. Take a look at the bigger picture by going to ...
https://earth.nullschool.net/#curre...a/winkel3=-276.82,13.17,618/loc=98.520,10.458
Click "Earth" to access the different parameters available. Find those that differentiate the circulation of a cyclone from the monsoon pattern. For example, the pressure altitude that best identifies the cyclones. After watching for a year, you should have found a reliable method. Let us know how you get on.

At 1000 hpa, that is approx. 364 feet of height, the prevalent wind is south-west wind coming from the ocean. I think, as these winds carry moisture with them they might cause rain if they are lifted up.

 

[Baluncore]

@Hall
To convert between altitude in feet, and pressure in hPa .
Po = 1000 ' pressure at sea level now, in hPa
P_alt = Po * ( 1 - 6.87535e-6 * alt_ft )^5.2561 hPa
Alt_ft = ( Exp( ( Log( P_alt / Po )) / 5.2558797 ) - 1 ) / -6.8755856e-6 feet

Here is a pressure height equivalence table.
10 hPa = 85,000 feet
70 hPa = 58,000 feet
250 hPa = 34,000 feet
500 hPa = 18,000 feet
700 hPa = 9,500 feet
850 hPa = 4,425 feet
1000 hPa = surface.

Look at the Wind at 250 hPa, up where aircraft fly on international routes. That is where the jet streams are best developed. Drop the marker to measure the wind speed. Notice there is always a jet stream over southern Japan, because the Himalayas obstruct the flow upstream.

Notice that you can select: Control; Choose Date; then go back to look at a data from years ago, but not very far into the future.

 

[Baluncore]

I think, as these winds carry moisture with them they might cause rain if they are lifted up.

Winds that blow away from the equator are also cooling gradually, so they tend to have clouds and drop moisture whenever they rise over a hill or range.