See Complete Book of Anchoring and Mooring by Hinz page 113. On the ABYC
hypothetical power boat of 45 feet and 15 foot beam the cantenary has 1
foot of
"droop"per 100 feet of rode at 30 knots and 0 feet at 40 knots. If your
boat is
smaller and has a smaller section it may be a little higher.
Hinz advocates the use of chain riding stoppers for all chain boats. He
points out
that all chain rodes are very good at parting or destroying something in
high winds.
They are also sufficiently noisey in high wind conditions to make sleep
difficult.