Quick Update: Multiple low-end severe threats this week for Gulf Coast

It wouldn’t be the Mardi Gras season unless we were talking about parades, right? Well, Mother Nature is celebrating with a parade of her own. And each system – like different floats in a parade – will have something different to throw out at the Gulf Coast.

Over the next week, there will be a parade of storms across the Gulf Coast region bringing chance for rain, storms and the potential for severe weather and flooding.

2/16/19 Evening precipitation estimates from the Weather Prediction Center for the next seven days

Timeline

STORM SYSTEM 1:

The first rolls through on Sunday with extra cloud cover and light to moderate rain. temperatures will be in the 70s ahead of the front and in the 60s behind it.

Severe weather and flooding don’t likely with the first system.

The forecast for this first system is pretty locked in and there is reasonable confidence that it will play out with no severe weather and just rain.

Rain totals will be near or below 0.5″ along and near the Gulf Coast

2/17/18 00z GFS 24hr precipitation estimate through Monday morning

STORM SYSTEM 2:

The second system rolls through on Wednesday morning. this will bring the chance for storms and the potential for severe weather on Wednesday morning for Louisiana, Mississippi and Alabama – Mainly south of I-20. North of I-20, flooding will be more of a concern than severe weather.

2/17/19 00z GFS sounding data pulled for Wednesday afternoon for southern Mississippi.

The cold front associated with the second system will hang up across parts of Louisiana, Mississippi and Alabama and be the focal point for showers and non-severe thunderstorms to continue through Wednesday evening and into Thursday.

The cold front that hung up will eventually lift north during the day on Thursday and into Friday.

Rainfall totals along or near the Gulf Coast will be between 0.5″ and 2.0″ with some spots picking up as much as 3″ of rain.

2/16/19 12z CIPS Analogs shows that in the Top 15 most similar atmospheric setups in the past, parts of the Gulf Coast have received more than 4″ of rain more than 30-percent of the time

The forecast for severe weather with this second system is still a bit uncertain. There are a few moving parts that will need to be ironed out in the coming days to discern exactly how much severe weather will be possible.

For now, plan on heavy rain, lightning, gusty wind and small hail as the main threats. The tornado threat isn’t zero, but at the moment, looks on the lower side.

STORM SYSTEM 3:

The third system arrives Friday morning with the area of low pressure, staying close to the coast as it rides by. Because of that, it is difficult to nail down specifics with the third system. The further north it travels, the higher the risk for storms and severe weather. The further south it travels, the lower the risk for storms and the lower the risk for heavier rain.

2/17/19 00z GFS showing Thursday evening rainfall across a wide area along the Gulf Coast

As of now, it looks like rainfall totals near or along the Gulf Coast will be between 0.5″ and 1.0″ with some spots seeing as much as 2.0″ of rain. But it will be pretty dependent on where this system passes the region.

The severe weather threat is still a bit uncertain and details will become available as more data comes in during the coming days.

STORM SYSTEM 4:

This storm system looks to roll through the area somewhere between Friday night and Sunday morning.

The good news: This looks like the last of the storm systems in the parade.

The bad news: This system, since it is so far in the future, has the lowest forecast confidence – for both timing and specifics.

2/17/19 00z GFS precipitable water values for Sunday morning.

For now, all we know is that this should be the last system in this batch and it would bring the chance for storms and the possibility of some flooding, too.



Author of the article:


Nick Lilja

Nick is former television meteorologist with stints in Amarillo and Hattiesburg. During his time in Hattiesburg, he was also an adjunct professor at the University of Southern Mississippi. He is a graduate of both Oregon State and Syracuse University that now calls Houston home. Now that he is retired from TV, he maintains this blog in his spare time.