I do not know of one that records and stores those overnight lows or daytime high temps.
I like the PE1 or PE2 or similar models of temp guns. They work well but you have to manualy work and record them. You can set up a rehostat (sp?) to keep a temp constant during low situations. Great question though.
All I found was what they call temp data logging systems. Here are a few listed here http://www.dicksondata.com/matrix/temperature_products.php?gclid=CM_2upaRg50CFSNQagodS1AIbg
You can buy High/low thermometers at any home improvement store. They register the highest temperature reached during the time period, and also the lowest. And it stays there for you to read it. All the while registering the current temperature.
FYI, if you look at the link I gave, you'll see that it does what you ask I think:
The Acu-Rite 00891 Digital Thermometer with Humidity Gauge and Clock simultaneously displays the indoor temperature, the outdoor temperature, and the indoor relative humidity. In addition, this thermo/hygrometer contains a precision digital quartz clock, and the time can be displayed as an alternative to the indoor temperature. This compact unit also features a minimum/maximum memory for temperatures and humidity and an LED backlight for the LCD display. The unit can be mounted on a wall or placed on a shelf, table, or desk.
Hmmm, the one I linked to provides, in one glance, temp of zone A, temp of zone b, and humidity of zone b. So I can see what my warm side is vs my cool side and what the relative humidity is in just a quick glance