Tuesday is the day of heaviest rainfall, especially across southwestern Louisiana and southeastern Texas.
(KLFY) -- We saw our first round of scattered storms this afternoon with storms dumping high rainfall rates of 2-2.5 inches per hour and gusty winds. This is typical of tropical 'squalls' like what we're going to see through the next few days. Some areas of Acadiana already received 2-3 inches of rainfall today, with widespread storms anticipated for Monday and Tuesday.
High-resolution models show waves of storms moving in through the day tomorrow. It won't rain all day, but multiple rounds of quick-moving storms could be possible. Rainfall totals will pile up in areas that receive multiple storms.
The aforementioned models are also now honing in on Tuesday being the day we could see the heaviest rainfall. These models agree on low pressure moving towards the Texas coast, with a wave of upper-level energy leading to training thunderstorms over southeastern Texas and southwestern Louisiana. In this type of environment, high-resolution models, and aspects they agree on, can give us a good idea of what could happen, as the pattern is very complex and storm timing and development are difficult to forecast. Both models shown here agree that Tuesday is the day of heaviest rainfall, especially across southwestern Louisiana and southeastern Texas.
This also lines up with the Weather Prediction Center (WPC) forecast of a 'moderate' risk of excessive rainfall on Tuesday. Because of all of these factors, I'll put the highest rain chance on Tuesday with the greatest risk of flash flooding.
Notably, both of these models show high rainfall totals in these areas, but it's also notable that the global models (European & GFS) are keeping the heaviest rainfall well down to our south, more across central Texas. This COULD be because the global models are showing the tropical development of the low pressure across the Gulf, while the high-resolution models, which are not for tropical weather, may be missing this.
It's also possible these high-resolution models may be picking up on upper-level waves of energy the global models are not, so rainfall totals will be very tricky through the next few days in regards to finding out which camp of models is correct. Either way, storms look to become more widely scattered and isolated starting Wednesday and through the rest of the week.
TROPICAL UPDATE
The low-pressure center mentioned above now has a high chance of development across the southwestern Gulf of Mexico through the next few days. It's currently on the Yucatan peninsula but will emerge over the Gulf tomorrow. As it's expected to near the Mexican coastline on Wednesday, this gives the system about 48-60 hours to develop into a tropical cyclone. It will be a slow process as usually these systems are very broad and take time to consolidate. For this reason, a tropical depression, or weak tropical storm, is most likely the most organized it will get before running out of time over water.
