Yesterday morning, as an addendum to a post discussing the possibility that current trends with something called the Madden-Julian oscillation could portend “a quiet couple of weeks for Gulf hurricanes,” the Houston Chronicle‘s “SciGuy,” Eric Berger, wrote: “Of course, shortly after I write this, the Canadian Model brings something, umm, interesting to southeast Texas coast early next week.”

Now, as of 2:00 PM EDT today, the National Hurricane Center’s Tropical Weather Outlook is picking up on that “something interesting.” The NHC writes:

A SURFACE TROUGH OF LOW PRESSURE ACCOMPANIED BY CLOUDINESS AND SHOWERS HAS MOVED INTO THE NORTHEASTERN GULF OF MEXICO. LITTLE MOTION IS ANTICIPATED TODAY OR SUNDAY…AND ENVIRONMENTAL CONDITIONS APPEAR TO BE FAVORABLE FOR DEVELOPMENT DURING THE NEXT DAY OR TWO. IF NECESSARY…A RECONNAISSANCE PLANE WILL INVESTIGATE THE AREA ON SUNDAY.

The system — which I assume will be labeled “Invest 91L,” though I haven’t seen that officially confirmed yet [UPDATE: confirmed] — is given a “medium” chance (20-50%) of developing into a tropical cyclone in the next 48 hours.

So, 91L, rather than the distant 90L and 99L, is now officially the most significant “worth watching” system in the Atlantic basin, because of its proximity to land (and very warm water with high heat potential). You can follow its progress on the visible satellite loop. Here’s an image as of 1:15 PM EDT today:

Again, nothing to worry about yet — but stay tuned, as they say.

UPDATE: Berger has a new post up about 91L. He writes: “The Canadian model is most aggresive in developing the system, bringing a tropical storm or even a hurricane to near the Texas-Louisiana border around midnight on Monday … Now, I don’t say this is likely. But it’s within the realm of possibility. … The best guess is that this system doesn’t do more than bring some needed rain to the northern Gulf coast. But at this point we cannot rule out it becoming something less desirable than that.”