Microlighters

I like to tinker with the weather charts to try and "predict" what mother earth will be doing to our flying machines. By noting what I think and then going out and "testing" the air (instead of the water ) and seeing how my prediction faired I think I would learn how to interpret the charts better. I am getting rusty and need to freshen up.

Here goes my first trial! Help me where I stumble please!

The Normal high pressure system prevalant over Gauteng has shifted west. A low pressure system is nicely nudged in north of Gauteng. QNH is 1017.

Wind flows from a high to a low pressure system. In the southern hemisphere winds always flows clockwise (when seen from above) around a low pressure area and counterclockwise around a high pressure system.

Since the isobars are so close together I predict a rather noticeable South Westerly wind over JHB/PTA. With my field nestled on the northern side of the Magalies I will find myself on the leeward side of this wind and it will really be messy out at the field!

Or am I totally off? X marks my spot on the Synoptic chart below.

http://en.wikipedia.org/wiki/Wind

Hi DH,

The 24 hour forecast for Jnb International and Lanseria confirm what you say.

FAJS 041400Z 041818 21015G25KT 9999 SCT030 TEMPO 0207 SCT008
FM1000 20008KT CAVOK TX12/12ZTNM01/04Z=

FALA 041400Z 041818 22013G23KT CAVOK TEMPO 0407 SCT010 FM1000
18008KT CAVOK TX14/12ZTNM02/04Z=

You can see that the wind is quite strong from the southwest. Tomorrow later in the day, around 12h00 local the wind will reduce significantly in strengh.
The weather pattern moves eastwards, and this abating of the wind would be because the big high pressure system moves over Gauteng.

Regards,
Arnulf

p.s. one of the best books on weather I found is: Understanding the Sky, by Dennis Pagen

well itsa crier 4 me ,, ended up in ICU after a bad nite with severe chest and leg infection/ pains - out now and in Gen Ward , nothing found yet? got a bit of colour back in dial hope im outta here soon

Junkie my namesake! Are you okay? Friend - I wish you a speedy recovery and I cannot wait to be at Morningside to see you zoot in with that one seater of yours!

With this cold I burnt up all my wood - supplier almost next to the field where I pick up a whole bakkie load for R100 to burn in the fireplace.

An excuse to get up early and go to the field I guess. FRLFF (Family Responsibility Leave From Flying) on Sunday - need to attend some events - so HAVE to fly tomorrow. The WX beaureau predicts light wind for tomorrow - that remains to be seen and if it blows over da mountain like i predicted I will be loading my bakkie with firewood when
I arrive!

Have to mention that that was the current synoptic chart at the time of my posting - still need to predict where they go.

DH - the weatherman - signing off for the night - reporting back tomorrow morning!

PS: I am willing to gamble that I will get 2 hours of awesome flying in tomorrow morning before I have to load the wood I still trust the weatherman more than myself!

Junkie wrote:ended up in ICU after a bad nite with severe chest and leg infection/ pains

Good grief! How'd you end up like that......fall outta your plane?
Hope you're doing better soon and outta their sooner :D

Duck Rogers

Ps. There's too many Ians on this forum

Hope you get better soon Junkie.

You must drink more rum man! That will keep the Cape winter chill out!

Interesting........

Actual weather this morning, Lanseria a bit late in posting their METARS. However, look at Jnb International, southwesterly at 17 kts, and Wonderboom calm. Suppose the Magaliesberg blocks the southwesterlies.

FAJS 050700Z 21017KT CAVOK 05/M02 Q1024 NOSIG=
FAJB 050700Z AUTO 22003KT //// // ////// 06/// Q1023=
FALA 050600Z 22005KT CAVOK 07/// Q1021 RMK RECEIVED AT 06:20=
FAWB 050700Z 00000KT CAVOK 09/M02 Q1024 RMK RECEIVED AT 07:06=

Had a glorious 2 hours this morning! Greatest weather in a LONG time, slow cruising around the Britz valley low level! Pity had to rush back for a 12o'clock thing in town!