A cloudless sky will suit batting first as the ball does not move around much once the initial shine has gone off the ball so batting gets easier allowing side batting first to in theory mass a big total.
The side batting first on a good pitch will get the best conditions under blue skies as wickets deteriorate with the help of the sun over 3/5 days.
Very rarely do sides batting last chase down over 275 runs to win anywhere.
Of course the reverse works just as well when there is cloud and a tinge of grass on the surface. The captain winning the toss will invariably bowl first as the conditions make this conducive.
Best way to use maximise this is via a ladder interface on software like Bet Angel etc watch the toss live via Skysports with stakes in place and ride the wave down. Jumping on a couple of ticks lower will allow more chance of being matched as the price is backed in.......
Stats/recent matches and weather
Generally as a rule I stay clear of Tests in the sub continent like India and Pakistan, (although we don't have to worry about Tests in Pakistan currently). The wickets here are generally roads and dust carts baked under the hot sun and big scores are common practice. Whilst backing the draw or laying the fave is an option here you will find the odds are usually fairly low so there is not masses of value there.
Now let's have a quick look at stats for various grounds around the world
Lord's England - Last 23 Tests only 7 Draws
Adelaide Oval Australia - Last 22 Tests only 5 Draws
Newlands, Cape Town SA - Last 22 Tests only 4 Draws
Kingston Jamaica WI - Last 17 Tests only 3 Draws
Wellington NZ - Last 16 Tests only 4 Draws
Picked these at random but you can see the pattern around the world outside the sub continent.
Key things to look for:
Look at past 10 years at that ground on stats guru on www.cricinfo.com to see if result % is high.
Check at least 2 forecasts for the next 5 days. (The Weather Channel, Yahoo, Wunderground and Met Office, (Met Office for English games)
Listen to the pitch inspection on Skysports.
Team news. Injuries to key players like Kallis for SA, Swann for England, Tendulkar for India can change your decision on a Trade.
Warm up games. I often check results for touring sides and their early warm up games to see which players are in form and which are not and how well the sides are playing. Carrying winning momentum in a Test series from warm up games like England have in Australia is a massive PLUS.
Laying the draw is a fairly safe strategy with the above factors taking into account. As is backing the home side who have won the toss and will bowl on an overcast day with a touch of green on it.
Early wickets either way will give you a profit.
Whilst wasn't available for the toss for the current test match i know from past games where with a good batting wicket and a cloudless sky the side winning the toss will see their odds drop sometimes up to 20 ticks. Reason being with the wicket so good and no overhead cloud conditions which will assist the bowlers the side batting first have the best of the pitch and should amass a big score allowing them to bowl out the side batting twice where the conditions may change plus via wear and tear on the wicket it will go against the side batting second/last.
Course it can go tits up like it has for the Aussies currently, LOL from batting first. But no reason why you cant nip in and out on the toss and green up before a ball is bowled. Have to be quick. I tend to put my back in ready a couple of ticks below as once that coin comes down every mother and his dog is on the market. Once matched ride it down then lay off.
Trading cricket personally is a good earner. I look at cricinfo for stats/records on the ground, Adelaide Oval in this case. I checkout 3 weather forecasts fro the area, team news, past head to heads and make a stance from there.
Generally though matches in India and Sri Lanka tend to be dust carts and like batting on a road where draws happen a fair bit. Tend not to touch them. In England, down under, SA and WI though results happen more often than not and providing the weahter forecast is good a lay of the draw works very well as they provide result pitches.
This current game in Adelaide 'should' go our way and the weather looks the only thing that can save the Aussies.
Same for one dayers too. IF conditions are favourable for batting, the side that win the toss will see their price plummet.