Seasonal postings are used in cases where the road's structural analysis indicates permanent postings may not be necessary as in the case of the freeze/thaw damage cycle.
Penn DOT Publication 23, Chapter 15, defines the Freeze/Thaw Period as: "The calendar period between approximately February 15th and April 15th, during which times the temperature results in changes (weakening) to the structural strength of the road surface. Additional restrictions may be required by the POSTING AUTHORITY due to severe weather and other unforeseen circumstances." A search of the website produced no specific guidelines or requirements for reductions in axle weight.
Hauling authorized by an Letters of Local Determination (LoLDs) shall be prohibited during the Freeze/Thaw Period unless a modification is specifically
requested by the User and approved by the Posting Authority. The User must confirm the effective dates of the Freeze/Thaw Period with the District.
Freeze/Thaw Reminder Letter (State of Pennsylvania):Calculate Oversize/Overweight Load Regulations and Prices Instantly with Oversize.io