Another heavy rain event is headed our way. I break it down for you here.

What you need to know about our heavy rain forecast

National Weather Service Houston

So here we are, another holiday weekend (Mothers Day in case you forgot), staring yet another heavy rain event in the face. Springtime heavy rain events in this area are notoriously difficult to forecast and this week's storm is no different. So while I can't tell you exactly where and how much it will rain in any given spot I do want to take this opportunity to explain the threat in a manner that is hopefully easy to understand.

Why is this all happening?

This afternoon a front is going to drop down through the state and stall over our area. This front will serve as a focusing mechanism for storms over the next few days. It will be both a source of the lift that is needed to form storms as well as a track for atmospheric disturbances – triggering mechanisms – traversing the area. If you walked outside today you undoubtedly noticed the absurd humidity. This is a result of copious amount of moisture being pumped in off the Gulf which is nothing but storm fuel. Beginning late Thursday and continuing through Saturday evening a number of disturbances will be riding along the stalled front triggering storms like pulses of electricity running down a wire, that also happens to have a bottle of lighter fluid pointed at it.

Once storms form they may be in no hurry to move, or may keep building on themselves causing some unlucky spots to be pounded for hours. This is where the flooding issue sets in. Another compounding factor will be that at times the airflow in the upper atmosphere (part of the jet stream) will split off in different directions over the area. This will provide an additional source of lift for the storms and essentially act as an exhaust fan helping to fan the flames. This will only serve to increase the rainmaking ability of the storms.

When is this all going to happen?

The general consensus is that this event will begin late this afternoon or this evening and continue through Saturday evening. It will not rain the entire time but waves of heavy rain and storms will be possible any time during that time frame as those atmospheric disturbances make their way across the area. The best advice would be to stay alert especially if you have plans to be out during that time, especially at night.

How much is it really going to rain?

By now I am sure you have seen on the local weather reports that anywhere between 3 to 5 inches will be common with some spots getting up to 12 inches. While it is true that some spots may indeed only see a couple of inches of rain in this event it is impossible at this time to determine where the rain bulls-eyes will be. Speaking of those bulls-eyes – these type of set ups can very easily over-produce so while the "official forecast" right now calls for high spots of 12 inches I really wouldn't be shocked if a couple of places picked up 15 or maybe even 20 inches of rain before this is all said and done.

The real issue in these situations is really rainfall rates, or how much rain falls per hour. For the most part our streets and drainage systems are designed to handle about 1 to 1.5 inches per hour. However, as we saw on Tuesday these types of storms in an absolutely juiced up atmosphere can produce rainfall rates that far exceed that, sometimes pushing 4 or 5 inches per hour. It is these high rainfall rates that will produce the flooding issues that we see. As I mentioned above there will be breaks in the rain over the next few days, the problem is going to be that most of the 10 inches someone gets may all fall within a 2 or 3 hour span.

Where is the worst going to be?

Unfortunately this is simply impossible to determine right now. Before you get all cranky on meteorologists no being able to get things right let me explain why. Many of the atmospheric features that determine exactly where storms form and produce heavy rain are so small that they cannot be seen until a few hours out, if that. The computer models that are typically used to aid in creating a forecast can only project conditions down to a certain area (their resolution). The models that forecast on a global basis can "see" things down to 6-10 miles wile some higher resolution models can "see" things down to just a couple of miles. So while these models are helpful in showing us the overall set up is ripe for heavy rain they are unable to accurately pick up on boundaries or other triggering mechanisms that may below their resolution. In addition to that, once storms form they create their own environments, often sending out additional boundaries which trigger more storms nearby. This chain reaction effect is also nearly impossible to predict with accuracy. While the science of meteorology is light years ahead of where it was even 10 -15 years ago it still is not perfect.

The key here is to prepare as though you will find yourself in one of these rain bulls-eyes and hope for the best. These areas will be relatively small and probably spread out across the area but it is just impossible to tell right now which neighborhoods will be the ones to get them.

I know heavy rain events cause a lot of anxiety and stress in our post Harvey world, but I want to assure you that there is no indication that this event will be another Harvey. Yes there will likely be street flooding and maybe some structure flooding in places but this will not be a widespread catastrophic event. This type of system is part of the reality of living on the Gulf Coast in a highly urban area. Heavy rainfalls are a fact of life and the best we can do is arm ourselves with the knowledge necessary to be prepared and use our best judgment to stay safe.

P.S. If you do not already, I would highly encourage you to follow the Houston National Weather Service office on whatever social media platforms you like to use. They are an invaluable source of information and are the ones who issue any warnings that may be necessary.


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Martin Truex Jr. won his 2nd race of the season last week. Photo via: Wiki Commons.

NASCAR returns to the Commonwealth of Virginia for the Toyota Owners 400 at Richmond Raceway. This is the first of two races here at this track as they will race on Sunday afternoon. This will be different from the normal night race they usually have here as this will definitely affect the racing surface considering how much the sun could make the track slick. It should be a fun race come Sunday.

Last week, Martin Truex Jr. passed Denny Hamlin to capture his second win of the season after rain moved the race to Sunday. He became the first driver to win multiple races after a fierce battle with his teammate Denny Hamlin. The race was filled with tons of wrecks including a fifteen car pileup including Brad Keselowski and Kyle Busch. It was one of the better races of the season as there was lots of beating and banging.

The race was not without controversy but not the kind you would expect. Early in the race Rick Ware Racing teammates Cody Ware and James Davison were involved in an altercation. The two were battling towards the back of the pack when Ware decided to drive through his teammate in turn four. The race got much worse for Cody Ware as he was involved in three more cautions all throughout the race. Many people around the sport were quite perturbed by his antics including broadcaster Mike Joy as he was audibly annoyed after Ware spun out later in the race. Many have questioned if the fifth-year driver should even be in the car and overall I can understand why some of those people think that. In his five years of driving, he has finished on the lead lap one time. I hope that he is able to figure it out and find success in the future, but this was not a good look.

The slump continues for two-time champion Kyle Busch

Throughout the race, Busch was running okay for the most part but towards the closing laps of the race he and Chris Buescher got together triggering a fifteen car pileup. Despite all this, he was able to rebound to a respectable tenth place finish. This has been more than likely the toughest stretch of his career since his championship in 2019. Many would say that the omission of Practice and Qualifying has really affected his performance. Whatever the issue is, this team really needs to find some speed, or he could be in danger of missing the playoffs. I look for this team to bounce back considering how talented he is.

Prediction

The driver that I have winning this week is Kyle Larson. This has been an incredible rebound season for Larson as he currently sits fourth in points. He is also second in laps led only to Denny Hamlin. Richmond has been a great track for him as it fits his driving style perfectly as he can run the outside line and find grip where others can't. This track is also rather sentimental to him considering he won his first pole award here during his rookie season in 2014. While he may not have the results he would want he has always been extremely fast here and even won back in 2017. I look for him to capture his second victory of 2021 come Sunday.

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