It seems when we get easterlies in WA they always are strongest at some time in the morning falling off no later than 11ish, and if easily kiteboardable (by that I mean 17knts+, not that less is not kiteboardable) often have a very narrow window. Does anyone know the geographic and climatic forces in play?
Im also interested it. Could it not just be like a reverse sea breeze. High pressure system inland making the nights clear and cold. High pressure wind goes anti clockwise. So the ground and air become cooler than the ocean and the land around the coast and the wind gets a turbo charge with temperature difference?
In summer it's called a land breeze, so yes opposite of a seabreaze.
After sunset, land cools faster so air above land sinks. Ocean cools slower so relatively speaking is warmer than the land so air above the ocean rises. The air descending over land moves towards the ocean to fill the void left the the rising ocean. That's where you get your easterlies from.
This is a localised effect and has very little to do with pressure systems.
In winter the landbreeze effect doesn't happen so any easterly are due to pressure systems.
Strongest land and sea breezes are when there is greater temp differences between land and sea. When they are similar, eg after a week of 35C, you get very still days. No good for kiting but awesome for evening beach bbqs.
Select to expand quoteFreddofrog said...
In summer it's called a land breeze, so yes opposite of a seabreaze.
After sunset, land cools faster so air above land sinks. Ocean cools slower so relatively speaking is warmer than the land so air above the ocean rises. The air descending over land moves towards the ocean to fill the void left the the rising ocean. That's where you get your easterlies from.
This is a localised effect and has very little to do with pressure systems.
In winter the landbreeze effect doesn't happen so any easterly are due to pressure systems.
Strongest land and sea breezes are when there is greater temp differences between land and sea. When they are similar, eg after a week of 35C, you get very still days. No good for kiting but awesome for evening beach bbqs.
The theory is good except land cools slower than sea and also heats up slower. The morning easterlies are because the land temperature is lower than the sea temp and stops when the land starts heating up. Air will always move from cool to hot due to hot air rising and the cold air moving in to replace on the land/ocean surface.
You find that when you don't get a sea breeze in simmer is because there is no low sitting in the top of WA and a high in the bight. This means a really strong high pressure system is sitting in the bight and it therefore counteracts the sea breeze in the afternoon. A low at the top of WA helps bring on s stronger arvo sea breeze.
Select to expand quotepaulwoller said..
Offshore = Not so good for kiting!i
Obviously depends on where you're kiting.. Offshore winds make for some of the best riding possible in a lot of cases (ie waves and freestyle).
Select to expand quoteDrury said..paulwoller said..
Offshore = Not so good for kiting!i
Obviously depends on where you're kiting.. Offshore winds make for some of the best riding possible in a lot of cases (ie waves and freestyle).
Could be true Drury, but from my experience in flying kites on Western Australia's west coast, the wind is nearly always 100% inconsistent gusty rubbish if Offshore
