Well, I'm in north central Florida but I have had a similar problem. Back around 65,000 miles I had an episode of carb overflow on the LH middle carb. Bike ran like crap & leaked fuel like crazy, only time it smoothed out was at high RPM. Fiddled around with it in a McDonalds parking lot & got it to stop leaking. Ran fine for another 13K or so.
Fast forward to about a year later & I got a case of the dreaded hydrolock, you guessed it, from the LH middle carb.

. Anyways I pulled the carb rack......

Then I pulled all the bowls & this is what I found in all of them. YUCK!! Actually the pic is AFTER I wiped some of the crap out with my finger!

LH middle carb was the only one leaking & caused the hydrolock {which BTW did no damage other than put lots of gas in the oil, WHEW!} but I cleaned them all. I replaced the float, needle & seat on the offending carb, replaced the failed petcock & added a fuel filter then put it back together. Didn't even have to replace the bowl gaskets. I did find rust in the fuel tank & I had it cleaned out & coated while I had it down too. Obviously what happened was tank rust plus just plain old dirt & gook built up over the years and slipped past the broken petcock, held the LH mid needle/seat assembly open & caused the problem. Bike now has 92,000 & all is well over the last 14,000 miles!

Sounds like you may have a similar problem just on a different carb.