On Wednesday, JPMorgan Chase (JPM 0.71%) shares were trading a penny shy of $50. Today, the superbank has broken through the $50 barrier, and is trading at $50.21 two hours into the day: up 1.09% since the opening bell after being up 0.13% in overnight trading.

Given the trials and travails the bank has been experiencing lately, and truthfully, ever since the London Whale trading scandal broke last year, this is a bit of a shocker -- one that defies easy explanation.

Market roundup
And before we even attempt one, here's what JPMorgan's peers and the markets are up to so far:

  • Bank of America is already up a big 2.16%.
  • Citigroup is also up big: 1.91%.
  • Wells Fargo (WFC 0.31%)-- the low-drama, Steady Eddie of big banking -- is up a more measured 1.15%.

The markets are all in the green so far, as well:

  • The broader S&P 500 is up 0.80%.
  • The narrower Dow Jones Industrial Average is up 0.50%.
  • The Nasdaq Composite is up 0.77%.

Foolish bottom line
Without a doubt, the primary explanation for today's share-price jump is the simple fact that the markets are all up. A rising tide is lifting all boats. But JPMorgan had a big day yesterday, too, while its peers didn't, and today's bull market can't explain that.

Yesterday, I posited that investors were perhaps coming to their senses regarding this upcoming, nonsensical proxy vote to remove CEO Jamie Dimon from the role of chairman at JPMorgan. In a nutshell, Dimon is being crucified for a $6 billion loss in last year's London Whale trading scandal at a bank with more than $2 trillion in assets, after presiding over three straight years of record profits.

On top of that, no big bank came through the financial crisis in better shape. Wells Fargo came through in as good a shape, but not necessarily better. And the strength of JPMorgan's balance sheet is due solely to Dimon's abilities as a risk manager. Were the botched London Whale trades an issue? Yes, but Dimon and his team went overboard in addressing them: Dimon practically replaced all of upper management last year in response.

So on top of today's bull market, I'm once again positing that savvy investors are realizing the good thing they have in Jamie Dimon, are putting the recent spate of lawsuits and regulatory actions into perspective, and are rallying behind what is undoubtedly a strong, well-run bank. JPMorgan probably shouldn't have broken $50 today, but thanks to a bull market, and savvy investors, it did.

Of course, the stock market is fickle thing: one day up and the next day down, usually for no apparent reason. As such, here at The Motley Fool, we emphasize keeping an eye on the long term. Focus on the fundamentals of the companies you're invested in, and check on your stocks once a month, or even once a quarter. Leave the obsessive ticker checking to the day traders: Your portfolio will thank you, even if your broker won't.