Light/heat/nutrient burn??

your plant looks very nice. :D But according to your diary you are a little above what is recommended regarding to temperature. Your air humidity is also in the High end of what's recommended and it seems like small droplets are gathering on the leaves.. Having it humid decreases the heat your plant can tolerate you should aim for keeping the temperature below 25 degree centigrade. During flowering the humidity should preferbly not exceed 50% on average https://www.thcfarmer.com/unsafe/fit-in/1100x1100/filters:format(webp):quality(85)/https://www.thcfarmer.com/attachments/bbm-chart-04-17-2017-resized-jpg.1141192/ Happy growing champ 👽

83f and over is bad. Flowering npk ratio is 1-2-3. Plant is showing discoloration from lack of potassium. Darker greens mean too much nitrogen in the plant.

30c is generalyl okay, but this sort of thing can vary by genetics.. plants that originated in warmer regions will tolerate warmer temps better, and those from colder areas will have a lower ceiling. 25-30C is generally the best range. 87F is just above that. So, ... possible, and not the only possibility. Look for nanner or pollen sacs with exposed nanners (anthers). lone nanners don't product a ton of pollen compared to a sac, so that can be fairly isolated. if there is a sac, you'll see a lot more coloration of pistils soon. use any weird foliar sprays? pistils are delicate.. easy to kill. Inspect stem and sorrounding areas.. dead sugar leaf? make sure thre is no infection there. top few nodes look a bit tight, but hard to tell in these pictures... that woudl be a sign that the light was a bit too intense. the brown pistil is not at the top though and slightly shielded, so i doubt this particular instance is light-related. wind can do this.. will kill the pistils sooner than normal and they will turn color sooner in kind. but again, would be more than one shielded pistil.. any pistils facing the fan directly would be showing similar symptoms if this were the case. definitely early to see.. if it proves to be isolated i wouldn't let it bother you too much.

This can be caused by a number of things. Tats hot. Turn up air flow over canopy tis will lower surface temperature Also. Ur in pre flower so ur light is still only 50-70% of its power right.. if you've no dimmer u use height (bulp/light from canopy distance further away) check the heat from your light hitting ur canopy. Bavk of hand test. .if u feel a substantial heat its too close and cooking ur pistils. They don't look 2bad mate.

I don't see in your diary what light you are using but it says it's 9 inches away from your plants, move it at least to 18" above the plant, maybe 24". This will help with heat. 87 is much to high, try to keep it 78 or under, 80 max You can download the Photone App on your phone and use the ppfd meter and try to get around 600 ppfd. Raise light intensity each week until you're around 800 ppfd. Try to keep light 18" or more above plant, if needed you can move it a little closer later in flower if the plant needs more light. Towards the end of flower, you can start dimming/lowering light intensity again.

Hello,on ne voit rien sur ta photo .