I show the outside temp/^F dew point, the inside temp/%RH/^F dew point. Also the a/c supply ^F temp/^F dew points.
The air flow is is approx. 600 cfm.
At every takeoff in your trunk there may be leakage at the seams. The duct ive seen looks like someone hacked two beer cans together at each register. This high pressure area may have significant leakage to outdoors, which means there is equal leakage of hot, humid air from outdoors at cracks and holes throughout the home to make up for the air leaving through your road barrier. Metallic tape applied to these seems can have significant impact, reducing loss of conditioned air and by default, depressurizing the home LESS which means less hot leaking IN.
If you take and share the pictures I suggested, you will get lots of comments about condition and whether this work is an opportunity.