Hi Bob and team.

Wading through this Met text and I am again a little perplexed.

My Question 1

Second last question is "What is the approximate gradient wind for each of the towns/cities?"

I can see all of your answers except for Perth and Darwin.

Perth: is in the middle of a HIGH but well south of the trough so winds are counterclockwise ie: I would say WNW but your answer is NE

Darwin is north of a LOW so winds are clockwise ie: I would say WEST but your answer is SE

My Question 2.

Your last question is what is the QNH at Perth?

The line is at 1012 both before and after the cold front. How is it 1022??

Please tell me what I am mis reading.

I notice that in my master file, the wind at Perth has been changed to north westerly. I don't know how come it's still saying north easterly in the current book!! Must have a talk to the printers about that..

As for Darwin the isobar on the very top of the figure that runs across the top of Cape York and on to very near Darwin would indicate a south easterly because of the anti-clockwise flow about the high and ridge over the ocean off Brisbane.

The low over Arnhem Land is a local circulation or secondary low that has formed in the weak trough. These lows are a feature of that part of Australia during late summer. They are caused by intense local heating over all that iron ore! One feature of these 'heat lows', as they are called, is that they tend to remain stationary over the hot spot while other systems move around them.

Gee, I didn't mean to make it that complicated!!

Cheers.

Hi Brenton,

No you're not misreading, see this thread..

www.bobtait.com.au/index.php?option=com_...14&id=431&Itemid=126

Posts 1-3 cover the Perth QNH issue =)

Once again Brenton, my master file has the QNH at Perth as 1012, so you are correct. That typo should have been changed ages ago. Seems like the answer is referring to a different synoptic chart. Looks like the printers have reprinted an old file.

Anyway, you can relax in the knowledge that you have not misunderstood it.

Thanks Bob, as you will see above this is the one year old text which I purchased in Moorabbin so it will not have been updated as per your response. Thanks again. At least I know I am not going troppo with all this "tropical" weather.