Another day of potentially heavy rain before typical July weather returns

Most of the Houston area remained dry—if cloudy—on Sunday. But the moist atmosphere in the wake of fading Tropical Depression Barry remained evident in areas such as Beaumont, which picked up 4 inches of rain. This moist atmosphere remains for one more day, and along with it the potential for heavy rainfall, before a drier pattern begins to build on Tuesday.

Monday

The highest risk for heavy rainfall remains east of the Houston metro area today, from Beaumont through Louisiana. Most of the city and surrounding counties will see less than one-half inch of rain. However, the eastern half of Houston remains at a slight risk of picking up an additional 1 to 3 inches of rain fairly quickly. This could cause brief street flooding in a worst case scenario. Otherwise, partly cloudy skies should help to limit temperatures in the low 90s, but alas the humidity will be oppressive.

Part of Houston faces a “slight” chance for excessive rainfall on Monday. (NOAA)

Tuesday

Rain chances will fall back to about 20 or 30 percent, as moisture levels remain fairly high in the atmosphere, but the region begins to feel the influence of high pressure. Any showers and thunderstorms that do develop should be fairly short lived. Partly to mostly sunny skies should allow high temperatures to climb back into the low- to mid-90s.

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Barry bringing heavy rains, storm surge threat to Louisiana

Just a quick afternoon update to note that the forecast for Tropical Storm Barry has not changed appreciably today. While it shows some signs of getting its act together, the strongest winds remain far from the storm’s center. As of 4pm CT maximum sustained winds are 40mph.

The latest model guidance continues to suggest that either a strongish tropical storm (more likely), or possibly a weak hurricane, will move into Louisiana on Saturday. The primary threat is heavy rains, with the potential for an additional 10 to 20 inches of rainfall across already sodden areas. Of further concern is that the Mississippi River is already swollen due to drainage from flooded Midwestern areas. Finally, there is the threat of storm surge, particularly along the Atchafalaya River and Shell Beach.

NOAA rain accumulation forecast for now through Monday. (Pivotal Weather)

In regard to Barry, the greater Houston area should remain in the clear, with only perhaps 40 to 50 percent rain chances this weekend—higher near the coast, lesser inland—and probable accumulations of 1 inch or less. Galveston will be more susceptible to higher winds and thunderstorms this weekend than, say, Katy, but the entire Houston region is likely to lie on the far periphery of Barry’s action. Tides are unlikely to be a significant problem, although rip currents could be problematic.

We’ll have a full update in the morning.

Tropical system in the Gulf almost a depression, threatens Louisiana

Good morning. As of 4am CT, the system in the Gulf of Mexico has nearly organized into a tropical depression (named Barry), and likely will become one later this morning or early this afternoon. While Texas isn’t entirely out of the woods, as there remains some uncertainty in the track and intensity forecast, this increasingly looks like a threatening situation for Louisiana. Because the state is next to Texas, and we have received so many questions from people living in, or traveling through Louisiana, we will continue to offer comprehensive coverage of Barry as the storm develops. If you’re living in Houston, please continue to pay attention to forecasts for the next couple of days, as tropical weather invariably offers up surprises. However, it’s probably safe to go about your business as usual this weekend.

Satellite image of the tropical system shortly after 3am CT Thursday. (NOAA)

Track

Confidence is increasing in the forecast track for a couple of reasons. First of all, we’re now likely only about 2.5 days away from landfall (likely along the Louisiana coast between Lake Charles and New Orleans), and errors for such a storm are typically less than 100 miles, even given the uncertainty with Barry. Secondly, although Barry has not yet formed a distinct center of circulation, there is nonetheless a decent clustering of ensemble members of the global models around such a solution. So a Louisiana landfall is likely for Barry, but not a certainty.

National Hurricane Center track forecast for the Gulf system as of 4am CT Thursday.

Intensity

Because Barry has not yet organized into a tropical storm, and perhaps only has a couple of days remaining sufficiently offshore, this should help to set a limit on its intensity. The official forecast still brings Barry to minimal Category 1 hurricane status prior to landfall, but confidence isn’t particularly high.

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Barry likely to form soon, already bringing heavy rains to Louisiana

Good afternoon. Based upon the latest model data, not a whole lot has changed in the forecast from early this morning. That is to say, there is not a whole lot of additional clarity, but nor do we have reasons for heightened concerns for Texas.

As expected, the National Hurricane Center went ahead and began issuing advisories on what will almost certainly become Tropical Storm Barry—citing it as a potential tropical cyclone. Here is the official forecast track as of 10am CT, and I would not anticipate much change when the hurricane center updates at 4pm CT.

Official track forecast as of 10am CT. (National Hurricane Center).

There are several big questions that are driving uncertainty in the track forecast. One is where the center of the storm ultimately develops, as this could cause a significant shift in the track (i.e. further to the southwest would lead to a more westerly track, closer to Texas). The second big steering issue concerns an upper-level system over the Great Lakes that will help to break down a ridge of high pressure over the plains states. The sooner this ridge weakens, the sooner the storm can begin to move north instead of being forced westward.

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