Hi SeattleBen,
It's good you've been removing the lemons, but we need some more info to help you - can you please post a photo of the tree and give us an idea of what kind of conditions it's living in? What kind of growing medium is it in? Is it potted? What kind of light does it get? Watering and fert schedule? Is the tree in Seattle? Lots of experts here who can help you with just a little bit more info...

Standard potting soil, which was top dressed with some chicken manure last year.

Right now its in a greenhouse where temps stay generally above 60 degrees F, it gets a fair amount of light, relative humidity above 60% generally. Its in a 12-14" clay pot and goes outside during the late spring when temps generally go above 55 (like Tomato growing weather). I fertilize very weakly maybe 1 time per month right now (30 / 30 / 30) - I figure if its flowering it needs some nutrition...

The tree is indeed in Seattle - so it probably is darker than it might otherwise like, though its on the edge of an area that gets supplemental light.. I can't figure out how to shrink the filesize of my picture.. Fancy camera has too many pixels

Without photos, it's very hard to give you any really significant or specific advice. If you can post several photos of your tree, that would help. But, based on what you've shared, I would say you're potting mix is much too dense, and WAY too much nitrogen of the type that would burn the heck out of a container plant (high in biurets). Chicken manure should really only be applied to in-ground plants, where the plants have the benefit of soil microorganisms tht can adequately break down that type of nitrogen. I would search our forum for "gritty mix" or "511 mix", and come up with something similar. For my container citrus (they are outside all year 'round), I use a slightly more dense version of 511 mix. I use a high quality cactus mix, perlite and small pine bark in a 3:1:1 ratio. I would never, ever put chicken manure on any potted plant. I use a water soluble fertilizer that has a good NPK ratio for citrus (Dyna Grow's Foliage Pro), as well as time release fertilizer formulated for citrus (try to find fertilizers with as close to a 5:1:3 ratio as possible). Your tree's roots are suffocating and most likely being burned. Your tree is flowering as a last ditch effort to produce fruit to replicate itself prior to its demise. I would also think about provided additional light, as citrus really need as close to a full sunlight environment as possible, most especially Meyer lemons, which tend to be more sensitive to light changes than other citrus.

Patty S.