12-04-2020, 06:05 PM
(12-03-2020, 11:35 PM)Fritzfishin Wrote: Drove by Mantua, caped this morning by noon I could see some open water, unsure on thickness, not a soul out there. Not much help but with the warm weather I think it'll be a while...I got curious and looked up a formula for this. Every year I'm bouncing in my chair at this point, thinking it'll be time any MINUTE now. I'm sure reality will vary with solar exposure and latitude, moving water, or warm springs, etc. but the formula is science-based.
For instance, I remember once hand drilling a dozen holes through 16" of ice in a shaded gully at the Gorge, reporting so on BFT, and getting flamed like a criminal for NOT warning people that the Confluence wasn't frozen over. So, don't stake your life on JUST the math here.
Once a lake as capped with ice which doesn't melt off during the day.....Add the high and low temp over 24 hours and divide by two. Take that number and subtract from 32 F. Divide that number by 15. That's how much ice will form in that 24 hours.
So, today at Mantua, the high should be 38 and the low is 15. (38+15) / 2=26.5. 32-2.5= 5.5 5.5/15= 0.367 Barring a warm wind, etc...the lake will add about 3/8" of new ice thickness in 24 hours.
Tomorrow, warmer. 39 +17 averages to 28, 32 - 28 = 4. 4/15=0.267, so barely more than a quarter of an inch.