Wear are you looking at these flights? I have heard that travel sights track you cookies and if you have been looking at the same flight multiple times the price will jump like that. Can you clear your cookies and search again?
Other then that I have no real advice I just thought I would throw that out there in case it isn't common knowledge (I'm pretty sure it is).
I have no advice because I am crazy and book my flights like 8-9 months in advance, just wanted to commiserate. I hate when a flight I'm watching (and expecting the price to drop) spikes in price. It always puts me on edge and makes me think I'd better buy before it goes up even more...and then, inevitably, the price always drops to a new low a few days later.
I'd say watch it a few more days and do a price alert on Yapta/Kayak in the event that it drops. I doubt it would jump up by much more if it just went up $150.
I still have my Yapta tracking from when we flew to Europe (into Amsterdam, out of LHR, from O'hare). It's from end of March, but the trend may help you. Prices stay were the same until I drop to next time frame (if that makes sense)
Day before: $1860
3 days before: $1600
wk before: $993
2 wks before: $940
3 wks before: $950
6 wks before $940
2 months before: $900
Generally the tickets were at $900 8wks before and them jumped jumped up to $940 just before 7wks before and stayed there until about a week before.
I would guess that the prices your seeing now would stay steady; although it is a different time of year.
Can you hold a reservation for one week? I can usually do this on AA online, not sure if it's because I'm a gold member. Prices typically dip on Tuesdays and Wednesdays so I would hold it until next Wednesday and then buy if the price doesn't drop. Travel agents can typically hold airfare for a couple of days too.
Looking at kayak.com, and I've looked from different computers but I'll try that just in case. But I don't think that would happen with an aggregator like kayak?
I don't know if kayak does, but I've absolutely seen it happen on Travelocity.