Tropical depression forms in the Gulf—but we still don’t know much

A low-pressure center has moved from Mexico into the southern Gulf of Mexico, and the National Hurricane Center has determined that Tropical Depression Three has formed. It likely will become Tropical Storm Cristobal within the next 12 to 24 hours. This doesn’t really change much from earlier, as we expected development when the center got over the warm Bay of Campeche. And the most important message I want to leave you with today is that we are a long way from knowing where this system is going, and what it’s going to do.

This image should help explain why:

Tropical Depression Three forecast track. (National Hurricane Center)

In this graphic I have zoomed in on the National Hurricane Center’s 4pm CT Monday five-day track forecast for the depression. Note that it is expected to spend the next four days wobbling around the Southern Gulf of Mexico. It may even go inland and die out, allowing another center to re-form to the north. One thing is sure, regions of Southern Mexico around the Bay of Campeche are going to get drenched.

The forecast models are really struggling with what happens this week as the storm swirls around the Bay of Campeche. Because of this, it is hard to have much confidence in what happens after the next four days. However, the most likely outcome is that some kind of tropical system will eventually move northward toward the Central Gulf of Mexico by Friday or Saturday. Unfortunately, it’s difficult to know how strong it will be, and where it will go thereafter.

Here is a plot of tracks for the depression in the European model ensemble forecast. “L” shows forecast position as of 7am CT on Monday. Highly speculative! (Weathernerds.org)

Based upon the ensemble modeling shown above, Texas and Louisiana remain the most likely destinations. Something may come ashore Sunday-ish, but we just can’t say whether it will take the form of diffuse showers, an organized tropical storm (most likely), or possibly even a hurricane. Looking ahead to the weekend we are so far into the thickets of uncertainty with this depression, given its wobbly nature over the next few days, that it’s not really possible to say more than that. Is heavy rain possible this weekend? Yes. Should we be overly concerned about it yet? Certainly not yet. Could a hurricane hit somewhere along Texas this weekend? Yes. Are the overall chances high, as in 50 percent or higher? As of now, at least, the answer is definitely no. Chances are significantly lower than that.

We’ll have more tomorrow, just don’t expect much more clarity on the situation for a day or two at least. We’re still definitely in wait-and-see mode with this storm.

This week should be drier, but weekend is unclear due to tropical disturbance

We expected a few scattered showers on Sunday, but nothing like what transpired near downtown. A rain gauge near Magnolia Park, inside the Loop, recorded six inches of rainfall on Sunday afternoon and early evening. This was due to very slow-moving storms associated with an atmospheric disturbance. We honestly don’t expect anything like that today, but the atmosphere sure surprised us this weekend. We’re also continuing to follow a possible tropical development in the Gulf of Mexico later this week.

Monday

Some light showers have developed this morning across parts of Houston, but these should fade out during the later morning hours. As high pressure builds in from the east, this should limit any afternoon showers or thunderstorms to western or southwestern areas of Houston. Skies will be mostly cloudy otherwise, with highs in the mid- to upper-80s for most.

The best rain chances today should be to the southwest of Houston. (Pivotal Weather)

Tuesday

By Tuesday we should probably begin to feel the influence of high pressure a little bit more in Houston, and this should lead to partly sunny skies and temperatures warming to about 90 degrees. Some scattered showers are possible, but most of the region should remain dry.

Wednesday, Thursday, and Friday

For now, these look like days that will be influenced by high pressure. This won’t be one of those classic summertime domes of pressure, but it should be enough to limit any rain showers to brief storms along the sea breeze, if at all. (Given our recent atmospheric blow-ups, it is hard to be entirely confident in this). Mostly, however, we should see partly to mostly sunny days with highs of around 90 degrees. Lows will be in the 70s.

See full post