Too many thermographers leave their imagers in the case during the summer. This comes, in part, from the way we used to work when imagers were not nearly as sensitive and our understanding of how to use them was limited to winter work.
Get the darned thing out and use it! In most places, on most mornings, you can get successful "winter" images; if not, keep the home closed up for the night and add a bit of heat in the morning before you arrive.
Once the day warms, heat flow and thermal patterns will reverse. On days when the sun is intense, direct solar loading will make exterior work impossible during the daytime and even interior work will require patience and understanding of how the sun affects things. But it is not impossible by any means!
A few hours after sunset if the evening is warm and the AC on, imaging can be spectacular from both inside and outside.
With a blower door and the building depressurized, air leakage will nearly always be detectable. The image below of a house in the Bay area on a warm early afternoon shows poorly placed figberglass batts in a cathedral ceiling.
Want to learn more? My colleague, Matt Schwoegler, will be presenting a (paid) webinar on July 6 on Warm Weather Thermography. See http://www.thesnellgroup.com/Content/thermal-solutions-conference.aspx for details. You can also see his recent excellent article in the May/June issue of Home Energy Magazine.
I'd encourage all readers to take their imagers to every single job. If you don't get good images, think about why you didn't and, when possible, modify your protocols so the next time you have a better chance.
The Snell Group
I have been setting up to inspect about 200 attics that are most likely completely out of compliance with ours(and any) reputable program specs. While testing a couple of remote camera configurations, I made a pass through the attic with my IR camera. As my attic was done correctly, The baffles (as shown on the left) were easy to spot.