Last year, on the 19th July 2022, a new UK temperature record of 40.3 °C was set in Coningsby, Lincolnshire; 1.6°C higher than the previous record from 2019. Will this record be broken in 2023?
1,000
3.00@parhizj Nothing alarming on EFI forecast, increasing NO bet.
~365 mana needed to adjust market to 9.4%. 0.9^27 * 365 ~= 26 mana
@parhizj Increasing NO bet slightly from looking at 7 day EFI and medium range temp forecasts, considering the market % is still too high for me. Bet size: 180 mana needed to shift to ~9.4%: 0.9^26 * 180 ~= 11 mana
@parhizj With EFI to July 25 showing nothing exceptional, I'm eliminating 1 more day from the top 10 records: 2/32 ~= 6.3%. I am increasing my NO bet since the market is at 8%.
Bet size: ~580 mana needed to shift to 6.3%: 0.9^25 * 580 ~= 42 mana
@parhizj
Looking at long range and extended range forecasts it seems that the 6.3% chance is justified, increasing my NO bet:
https://manifold.markets/tkillestein/what-will-the-maximum-temperature-b?r=cGFyaGl6ag
@parhizj Nothing alarming in EFI medium-range or extended range forecasts. Increasing NO bet.
~350 mana to shift to 6.3%: (0.9 ^ 21) * 350 ~= 38 mana
@parhizj With EFI to August 6 showing nothing exceptional, and the extended range EFI showing only a slightly high abnormal temps in late August, I'm eliminating 1 more day from the most recent (1990s+ era) of the top 10 records: 1/32 ~= 3.1%. I am increasing my NO bet since the market is at 7%.
Bet size: ~519 mana needed to shift to 3.1%: 0.9^14 * 2270 ~= 519 mana. This is too much liquidity wise short term so I am capping it at 100.
@parhizj Not going to increase my bets in this market any more given I need the liquidity. Checked the EFI and extended forecasts, it looks very unlikely still.
Meteorologists forecast 45% chance ("2.3 times the normal figure") that this summer will be "hot". Plus there's an El Nino this year. --> You should bet against me!
@ArunJohnson From your article's headline: "There are no signs yet that last year’s 40C will be breached again, but meteorologists predict such peaks could become the norm"
Whether Britain will again experience a breach of the 40C level remains unclear, however. “There’s no strong indications for it,” said Mark Bevan, a senior Met Office adviser. “On the other hand, we saw it last year, so it’s obviously inherently possible. So never say never.”
Based on that article I wouldn't actually bet YES. the 2.3 times normal figure lacks (quantitative) context with relation to this question.
https://en.wikipedia.org/wiki/United_Kingdom_weather_records
Lets consider post 1990 a different era: for the past ~32 years, 5 records were broken. That leaves a probability of about ~16%. It looks like the median for when the records get broken (based on the last 10 record breakers is June 18). From this small sample, it looks like only 1 record was broken before July 11 (10%), so 90% of the records are broken after July 11. Examining forecasts for the next 7 days it seems very unlikely (>99%) a record will be broken, so we will just use the 90% figure in conjunction with 16% (excluding this next week) ~= 14.4%.
I would need to spend 900 mana to bet NO to adjust the market to this probability from 33% to 14%. Given that I am only about 2% confident in updating this prediction correctly every day using more reliable 24H forecasts and (keeping an eye on longer range forecasts) for the next 38 days out (90% confidence in each forecast each day: 0.9^38 ~= 2%), I am reducing this initial bet of NO to 18.
@parhizj TBH I would have bet this down to 15% myself, except I've already got a disproportionate amount in it. Always felt way too high, I'm wondering if my description, and the warming trend, gave people an unrealistic first impression of the probabilities.
@TomFinnie I also vacillate sometimes being unsure how to size my bets given I expect to update several times (and that future bets are going to provide less return since the market will also update)
@parhizj After 6 days, I am increasing my NO bet. Medium-term forecasts show nothing alarming, nor do EFI reanalysis for 7 days out. Need ~145 mana to decrease market down to my original estimate of 14.4%, limiting the bet size with (0.9^32) * 145 = 5.