The following Preparing for Storms is an excerpt from the book Anchoring - A Ground Tackler's Apprentice  (a load table and other tips) by Rudy and Jill Sechez.

LOADS ON GROUND TACKLE

Boat Size    Wind Speed
(knots)    Load on Ground
Tackle
20’ sailboat    15    90 lb.
30’ sailboat    15    175 lb.
40’ sailboat    15    300 lb.
50’ sailboat    15    400 lb.
20’ sailboat    30    360 lb.
30’ sailboat    30    700 lb.
40’ sailboat    30    1200 lb.
50’ sailboat    30    1600 lb.
20’ sailboat    45    720 lb.
30’ sailboat    45    1400 lb.
40’ sailboat    45    2400 lb.
50’ sailboat    45    3600 lb.
20’ sailboat    60    1440 lb.
30’ sailboat    60    2800 lb.
40’ sailboat    60    4800 lb.
50’ sailboat    60    6400 lb.
*    These figures are for a “traditional-sized” sailboat, anchored in sand, where there is moderate protection from seas and the boat having the freedom to oscillate.

1. All components must be sized to have a Work Load Limit (WLL) that at least matches or exceeds the greatest load on the boat.

2. Rope must be sized to have at least a tensile strength 8x the highest load that will be on the boat. Then, find a diameter of line that has this tensile strength. If secured in a slip, to absorb surge loads, install some form of a stretchable mechanism, such as one product marketed under the name of “dock line snubber”.

3. If anchoring, calculate scope by adding together: the depth of water, the boat’s freeboard, any additional height of tide, the depth the anchor will bury, the height of the storm surge, and the height of the waves, then multiply that by at least 10.

4. Anti-chafe gear - must be plentiful and where necessary, multiple layers.