Seasonal or winter assumption variance in regards to delays question

every month any time related element should be noted for that month and reconciled the next month. For example I am doing an June update recording progress and delays thru June. I then submit my updated schedule WITH the delay fragnet and TIA (Time Impact Analysis). This should then be reviewed for approval and or commented on by the owner or its representitive. Then any time extension should be included in a contract modification that should be issued in July and incorporated into the July updated schedule. 

As the project moves forward in time people leave the project and memories get foggy. ANY delay should be incoprorated into the contemporaneous schedule.   

Even though your title says seasonal you did not say that the delay was seasonal but I will address that also.

Every month any time related element should be noted for that month and reconciled the next month. For example I am doing an June update recording progress and delays thru June. Let's say that anticipated adverse weather for June is to expect 8 dasy of adverse weaher with would be based on the specifications which should be based on the NOAA Historical geographical data for that geographical location. So lets say that I document that I experienced 10 days actual adverse weather for June. Then this means that 10 days minus the 8 days that are to be anticipated equal 2 days. In this case the contractor is ebtitled to 2 days of a non-compensable time extension. This should be included in the June schedule narrative. 

This should then be reviewed for approval and or commented on by the owner or its representitive. Then the 2 day time extension should be included in a contract modification that should be issued in July and incorporated into the July updated schedule and the project must finish date should be extened by 2 calendar days.

This should be done during each schedule update. 

There is NO CREDIT for weather that DID NOT HAPPEN.