Thread: The BOM cannot get tomorrow's weather right

Anything over 20 mins in duration is rain.

Under 20 it's a shower.

Did you have rain or showers?

If you had rain they were right.

It has been raining here all day, but I think we would be lucky to have had 5mm, just been that continual light annoying stuff.
Overall I think the BoM do a fairly good job, rainfall amounts is one of the harder things to predict.


Martyn

Originally Posted by PhilipA

Well all the "rain" has now inundated Sydney as promised by the BOM.

We on the Central Coast at Avoca would have been lucky to get 5MM, just enough to be a nuisance and not putting even 25MM in the tank compared with the forecast of 50MM over the 3days. I noted 3.2MM for Sydney today from 9AM.

Hmmm, are these the same people who are forecasting future El Nino etc?
Regards Philip A

If you've ever looked closely at a rainfall forecast, you'd note a range of rain amounts and an estimate of the probability of rain.

If you've ever looked at the weather radar you'd notice that rain often comes from things like "storms" or "lumps" so your rainfall could be quite different to the amount that fell 10km to the north of you.



I wouldn't go blaming the BOM for your failure to understand what weather works like.

Originally Posted by bee utey

If you've ever looked at the weather radar you'd notice that rain often comes from things like "storms" or "lumps" so your rainfall could be quite different to the amount that fell 10km to the north of you.

Or even 1km if it comes to that....

We certainly had rain here yesterday. Very strong winds a day or two before put heaps of leaves, bark and other debris on the ground. Then the rain washed it all into the gutters. Hence, blocked storm water drains and flooding all over the place. All this, when two days before it was 40+ degrees. At least it put the fires out....

Coop

Anything over 20 mins in duration is rain.

Hmmm I don't know.When at night it is so light that you cannot hear it, but probably not over 20 minutes during the day. BUT rain periods should mean rain periods when we only got drizzle and the BOM does have a category of drizzle.

I guess the point I am making is that if the BOM with all its supercomputers and models cannot get the weather magnitude right the next day what hope have climate models?

I recall once when I was riding my motorcycle to work I used to check the radar before going . The radar showed no clouds and the forecast was fine.
I got drenched going to work, and when I emailed them and said how come , they replied that the radar did not show rain , only clouds and that it did not show clouds under 3000ft(AFAIR) , so tough luck.

I am quite aware that weather ( and climate) forecasting are difficult and perhaps should be couched in probability terms, but the BOM does not do that on their website or on the part I look at anyway.

BOM fact.....over 20 mins duration is rain.

Wondering why you are making these statements if you don't know......

It IS couched in probabilty terms.....right in front of me on BOM forecast it shows the possibility of rain expressed as a percentage.

cheeese.......

We haven't had rain, showers or drizzle for 4 weeks. The BOM said this weekend would be wet and they are 100% right and I am 100% happy. About 30mm so far and still coming down. By and large they get it pretty right. We live on the edge of two forecast districts our weather is a mixture of both forecasts depending upon prevailing winds etc. When I look at the radar during rain events the variability is quite noticeable and with the long views from our place and neighbours reports when storm cells come through the difference can go from 2mm to 25mm over the space of 2kms.

Hallelujah it is now raining.
My post was successful. Just as good as going camping.
Of Course last night at 11Pm the BOM was saying rain periods, but this morning rain. This is for Gosford which is the nearest on their website interactive map.
They must have looked out the window.
Regards Philip A