[V8] Odd Temporary (I hope!) Stall Issue - Input Requested

[daves745t at optonline.net]

I was planning on posting about my first 1000 miles in the 90 V8Q and how damn impressed I have been on all fronts - the comfort, the power, the handling - just absolutely enjoying the crap out of her.  And then I had a weird thing occur today . . . 

I live in northern NJ and had to go down to the Atlantic City area today. Well, weather-wise, it was awful, started out as rain, changed to sleet and then to snow. The temp dropped from the mid 60s yesterday to the 20s by this afternoon.  The radio was abuzz about accident after accident, but the V8Q performed flawlessly as it has been since getting her back after the timing belt was done. 

Anyway, the 125 miles north was an icy, slushy, snowy mess. I routinely check my gauges out of habit and all was fine on the highway. But when I got off I was in much slower traffic, very stop and go for about 20 minutes or so. I stopped for coffee and it was at that point that I noticed the coolant temp gauge had jumped from the normal running temp of just under half way to just past about two-thirds, but it was not all the way to 250(?). However, no warning lights or beeps of any kind came on and the self-check was OK. I got out of the car and found that the entire front end - grill, headlights, front spoiler was encased in several inches of frozen slush. I got the majority of it off, but when I tried to restart, the "CAT" light stayed on, the car ran rough and would sputter out and die when put into gear.  

I was literally only blocks from home, so I just walked home with a pit in my stomach.  I went back several hours later and she fired up immediately, no funny engine noises, no warning lights/noises, and nothing out of the ordinary during the few minute trip home.  

Obviously the lack of air flow in the stop and go traffic caused the temp to spike and I'm thinking that I also heated up those cats pretty darn good and that may have caused the poor running/stall until they cooled.  Does that sound plausible to you guys or do you think I'm looking at something more sinister - sensor related? 

I guess I'll be finding out one way or another when I go to work tomorrow . . . but I'm wondering if I've created a hot start problem or potentially damaged the cats - man, I hope not. Thoughts?

-DaveM