Matt Lanza

A quieter week after an incredible rainfall forecast, as huge footprint of major flooding continues

Headlines

  • Weather forecasts verified exceptionally well with the ongoing Mid-South flooding.
  • Numerous rivers are experiencing or soon will experience major flooding as all this feeds into the larger Ohio/Mississippi Basin.
  • A much quieter week is expected this week.
  • Next week may be a good bit stormier, however.

Exceptional flooding, exceptional forecasting

Now that it’s over, we can say that last week and weekend’s rainstorm sadly lived up to the expectations set days before. Take a look at the map comparison below. Use the slider to toggle between the rainfall forecast issued on Monday and the observed rainfall based on MRMS analysis.

A comparison of the rainfall forecast issued Monday and the observed rainfall late last week and weekend. Additional rain was expected south and east. (Pivotal Weather)

Is this a perfect rainfall forecast? No, but my goodness it’s pretty darn close. The Weather Prediction Center, which is an arm of NOAA issues these larger scale precipitation forecasts daily. I reference these forecasts regular in my day job and for our readers both in Houston and elsewhere. They’re valuable. But they have exceptional utility ahead of major events such as this flood in the Mid-South. The folks at the WPC, much like those at other national centers under NOAA’s umbrella are the absolute best of the best in our field when it comes to marrying forecasts with historical analysis and numerical prediction models. As a public service, I’ll remind you that the budget cuts currently being proposed to NOAA will cost more in both lives and property in the long run than they’ll save in the short run.

All that said, this forecast was exceptional, but so were the impacts. Here is a look at the wide swath of double-digit rainfall totals seen through this event.

A non-comprehensive look at rainfall totals in excess of 10 inches across the lower Ohio Valley and Mid-South. (NOAA)

Many rivers in western Kentucky, southwest Indiana, or southern Illinois will be at their highest levels since 2018; in some cases on the White River in Indiana, it will likely be their highest levels since 2005 or 2008 floods. A few spots on the Kentucky River will actually set new records from this event.

The Kentucky River is setting new records in places. (NOAA)

In Frankfort, the state capital, a record from 1978 is threatened from the Kentucky.

Those recurrence intervals are pretty amazing from southwest Tennessee through central Kentucky. For Memphis, this was the 2nd wettest four-day stretch on record, just falling about an inch shy of a June 1877 flood event there. Six flash flood emergencies were issued for the event across Arkansas, Texas, Mississippi, Tennessee, Kentucky, and Missouri.

Rivers that are forecast to be in moderate (red) or major (purple) flooding encompass a huge swath of the Mid-South and Ohio Valley. (NOAA National Water Prediction Service)

Dozens of river gauge locations are expected to experience major flooding. All this water is going to flow into the Mississippi River eventually, and depending on where you are on the river, the forecast crests right now are the highest since somewhere between 2011 and 2020.

All this water is flowing into the Mississippi, which is expected to reach major flood as far south as Baton Rouge by next week. (NOAA)

This one will go down in the record books with some of the bigger Mid-South floods.

Quiet week for the most part

Fortunately, the forecast this week there looks fairly calm with some rain later in the week, likely at manageable levels. Elsewhere across the country, we get to still discuss winter. Cooler temps will allow for some locally heavy snowfall from Ontario, across southern Quebec and into interior northern Maine, where as much as 4 to 8 inches could fall tomorrow.

Winter is not quite over just yet. (NWS Caribou)

Otherwise, the late week storm system mentioned above may allow for a return to some fire weather conditions in the southern Plains. Unlike in March, however, quite a few areas have seen some decent precipitation recently. So hopefully that puts a bit of a lid on severe fire weather concerns for the Plains.

Back at it next week?

I think the next significant weather item to watch will be a chance for multiple days of severe weather next week in the southern Plains. Exactly what that looks like or how it unfolds is TBD, but there are definitely signs in the models that after a quiet-ish week this week, we pick up the pace again next week.

I’m going to aim for a couple more posts this week. One will discuss the hurricane outlook issued by Colorado State. I may try to get another one later in the week on water issues and low snowpack in the interior West. We’ll see how this week goes!

Going, going, gone?

I want to leave you with a couple fun links today. As baseball season ramps, up, there are two new ballparks in play this year with the A’s in Sacramento and the Rays playing at Steinbrenner Field in Tampa. Over at Fangraphs, Michael Rosen did a two-part look at the weather effects in the new ballparks. Both have interesting quirks. Sacramento’s field will have some of the lowest humidity of any ballpark in the league. Tampa will have some fascinating winds which may make Rays games pretty fun to watch. Anecdotally, I did watch parts of some Rays games during Opening Week, and there were some interesting dynamics in play on fly balls. I encourage you to check those links out!

Looking at the next 24 to 36 hours of severe weather and flooding in the Mid-South

Thunderstorms are cranking up as anticipated this afternoon all across the Mid-South all the way north to northern Indiana with a bunch of severe thunderstorm warnings about 7 tornado warnings at the time I am writing this.

A static radar image as of 5:30 PM CT over the Mid-South and Midwest. (NOAA)

A “high risk” for severe weather was issued from eastern Arkansas to just south of Evansville, Indiana today. The reasons included the potential for strong tornadoes, very large hail, and very strong wind gusts. Basically, it’s about as optimal a broad-scale severe weather setup as you could reasonably look for. It could also end up being a tornado outbreak day as well. We’ll see what happens over the next few hours, but as these storms march east, it’s likely that all severe threats will increase this evening.

A high risk (5/5) is in place for severe weather threats between eastern Arkansas and western Kentucky. (NOAA)

We’ve been discussing the rain risk the last few days and the potential for catastrophic flooding to emerge in these areas. Round one tonight will start that process. We can get a sense of the potential for rain over the next several hours looking at the HRRR model, which is a high-resolution model we use for thunderstorm forecasting. It shows a bullseye of 3 to 6 inches showing up between now and 7 AM CT on Thursday in western Tennessee, just east of Memphis.

Rain forecast from the HRRR model between this evening and Thursday morning showing 3 to 6 inches in western Tennessee. (Pivotal Weather)

That area between Jackson and Dyersburg, TN may be at highest risk for flooding from this first round of rain. Once the severe weather exits tonight, the front will basically stall out over or just north of the Tennessee Valley. As that happens, the severe weather threat for tomorrow will shift back south and west some into northeast Texas, Arkansas, and western Tennessee.

Thursday’s severe weather risk shifts farther south and a bit west. (NOAA)

What about the rain? Tomorrow’s heaviest rains are going to focus near or just north of where tonight’s heaviest rains will occur. According the Storm Prediction Center’s high resolution ensemble forecast, the average rainfall tomorrow will peak around 2 to 4 inches in northwest Tennessee, between Dyersburg, Martin, and Clarksville. There is some degree of uncertainty in how much exactly falls and where it falls. So all of western Tennessee should be on guard.

Average rainfall forecast for tomorrow across the Midwest and Mid-South shows a bullseye in northwest Tennessee and parts of Arkansas. (NOAA SPC)

Arkansas should also watch this, particularly between Pine Bluff and Memphis, TN. Some of the “under the hood” guidance indicates that as much as 5 to 8 inches of rain could fall in these areas. As such, a high risk (level 4 of 4) exists for these general areas tomorrow for flooding rainfall.

A high risk (4/4) for flooding focuses on northeast Arkansas, western Tennessee, and portions of Kentucky. (NOAA WPC)

High risks for flooding are important to denote because they are extraordinarily well correlated to damaging, deadly flooding. The vast majority of the worst flooding we see in this country occurs on these high-risk days. So tomorrow could be the first volley in a very bad series of them.

Beyond tomorrow, the general trend will be to lift the rain north on Friday into the Ohio Valley or even farther north before it slowly, painfully slowly sags back south and east on Saturday, finally exiting Sunday morning. This period will probably see additional bad flooding spread to the north and then back south again. Again, this appears to be an extremely rare, catastrophic flood event that will unfold over multiple days beginning tomorrow across Arkansas, Tennessee, Kentucky, and portions of Illinois, Indiana, Ohio, and Missouri. Additional “high risks” are likely to come.

Potential for catastrophic flooding by the weekend in the Mid-South and near the Ohio Valley

The National Weather Service in Paducah, KY did not mince words this afternoon in their briefing on the upcoming rainstorm across the Ohio Valley: “Significant and potentially historic rainfall will begin Wednesday afternoon, with numerous rounds of heavy rain continuing into the first half of the weekend, leading to potentially catastrophic flash flooding.”

I have a whole post eventually coming to my Substack page on words and how we use them. But suffice to say, whenever the NWS uses a word like “catastrophic,” it is an extremely deliberate decision that more than one person agrees to. In other words, they understand the weight of the word “catastrophic,” and after discussing it as a team, they agree to use that phrasing. Because they’re convicted of an outcome that they believe will indeed be possibly catastrophic.

National Blend of Models (NBM) forecast rainfall through the weekend with pockets of 10″ or more between northeast Arkansas and southern Indiana. (Pivotal Weather)

And the model data today continues to provide ample additional support for a wide ranging, widespread, potentially historic and/or catastrophic outcome. Within their area forecast discussion, the technical briefing the forecasters at the NWS provide that essentially explains or justifies their decision-making, the Paducah office maintained that type of language. “We cannot overstate the extremity of the flooding danger with this event incoming and these historic forecast rainfall amounts.”

To the north, in Indianapolis, their forecast discussion stated it had the potential to be one of the most significant rain events in the last 15 years. “This has the potential to be near the top of the list for highest impact heavy rain/flooding events for central Indiana in the last 15 years.”

Same story in Memphis, where their office also warned of catastrophic flooding. “Catastrophic flooding remains possible in portions of the Mid-South Wednesday through Saturday as the previously discussed front stalls right along the I-40 corridor.”

I wanted to just post that so folks, especially new visitors, didn’t think that we’re just randomly going ballistic over something. No, this is objectively a very serious threat between Arkansas and Ohio that is going to make the national news. All we can do at this point is hope for the best.

A very serious severe weather threat

There will also be severe thunderstorms at times, especially tomorrow (Wednesday) and Saturday I think.

A moderate risk (4/5) is in effect for Wednesday between central Arkansas and southwest Indiana due to possible tornadoes, damaging winds, and large hail. (Pivotal Weather)

Being from Houston and having dealt with a 5-day rain event in 2017 by the name of Harvey, these types of events are long-duration tests of will. I’ve found that rather than trying to focus on every single element of the threat, it’s better to break it into manageable chunks. Today, that’s the overall rainfall threat (as laid out above), in addition to Wednesday’s severe threat. The moderate risk (4/5) was issued to cover all forms of severe weather (strong tornadoes, large hail, and damaging wind gusts), and all of them look potentially potent tomorrow. I will refer you to your local NWS office or some of the other fine weather blogs out there for more on the severe threat. There will be additional rounds of strong to severe storms across the Mid-South through Saturday, with perhaps Saturday itself being the second peak day of the event, in addition to peak concerns about flooding.

Stay safe everyone.

Near record rainfall possible, with flooding concerns growing in the Ohio and Mississippi Valleys this week

Yesterday we jumped into the thought process behind the flooding concerns for this week. The update today is not much better. Over the last 30 days, rainfall has actually been manageable in the Ohio Valley and points south, with most areas seeing near normal or slightly below normal rains.

Percent of normal rainfall since March 1st. Red = drier than usual. (High Plains Regional Climate Center)

You can see that most of Kentucky has been slightly below average, with much drier conditions to the west into Arkansas and Missouri. Yesterday’s rainfall is missing from here, but in general, the theme has been at or slightly below average since early March.

It’s been another story in 2025 as a whole. We had terrible flooding in Kentucky earlier this year. Soils still haven’t entirely recovered from the wet start to the year, and you can see it in soil moisture readings today.

Soil moisture anomalies before yesterday’s thunderstorms were already higher than normal. (NOAA CPC)

So, we look at the antecedent conditions ahead of a heavy rain event to get a sense of how much water can be absorbed initially. And the answer here is, “some but not that much.” Unfortunately, it’s not just one round of rain we’re expecting in the Ohio and Mississippi Valleys but rather several rounds between Wednesday and Saturday. Yes, there is a notable severe weather risk. But the flooding risk needs to be stressed a lot.

Not only is it significant, but it’s also potentially historic. Below is a table of the 5-day rainfall forecast from Monday morning’s run of the NWS National Blend of Models (NBM) for some Mid-South and Ohio Valley cities, as compared to their 5-day record rainfall totals historically. Currently, both Paducah and Jonesboro are forecast to exceed their prior records, while Evansville and Dyersburg, TN are only an inch off records.

LocationForecast Wed-SunStanding 5-day rain record
Little Rock, AR9.5″12.9″ (1882)
Evansville, IN9.8″10.88″ (1910)
Dyersburg, TN9.9″10.55″ (2016)
Cape Girardeau, MO10.4″14.51″ (2011)
Jonesboro, AR10.8″10.0″ (1937)
Paducah, KY11.0″10.63″ (1983)

So this is not just me saying it’s going to rain a lot.

The culprit is a cold front that is going to drop into the Midwest and Mid-South on Wednesday afternoon. As this happens, it’s going to run smack into a building ridge of high pressure over the Southeast that will be approaching all-time April records.

Near-record 500 mb heights for April are likely in the Southeast and off the East Coast. This will force the cold front over the Midwest and Mid-South to stall. (PolarWx.com)

This will slow or halt the progression of the cold front, forcing it to stall out over the middle of the country, extending from roughly northeast Texas, across Arkansas and into the Ohio Valley. With a stalled front, and atmospheric moisture running very much above normal in this area, you have a recipe for a multi-round heavy rain event. The exact timing and specifics of each round are tough to pin down, but we know this much: There is a strong model signal for copious amounts of rain in the area between about Arkansas and Ohio. And the flooding risk is high enough to warrant three straight days of moderate excessive rainfall outlooks (level 3/4 Wednesday and 3/3 Thursday and Friday) from the WPC. I would expect at least one or two high risks to be issued when we approach later this week.

Wednesday’s excessive rainfall outlook includes a moderate risk (level 3 of 4) from northeast Arkansas through southwest Indiana. This area expands farther and wider on Thursday. (Pivotal Weather)

The day 4 and 5 moderate risks indicate pretty high confidence in significant flooding potential. I showed the forecast rainfall from the NBM above. That’s just one tool used, meant to show the potential for heavy rain. The current NWS Weather Prediction Center outlook for total rainfall shows a massive area of 8 to 10 inches of rain through the weekend.

Rain totals of 6 to 12 inches with higher amounts possible cover a huge swath from northeast Texas through southwest Ohio. (Pivotal Weather)

This is going to be a high impact, wide ranging, significant regional flood event. So how can this go wrong? Well, for one, you could see focused areas of rainfall embedded within the broader area, so we see some places forecast with 6 to 12 inches to see more like 2 to 4 inches with bullseyes of 10 inches or more. Much of this will depend on the strength of the Southeast ridge and where exactly the front stalls. For example, if the front ends up stalling farther north than anticipated, places like Dayton or Indianapolis or even St. Louis could see much higher rain totals, whereas if the front stalls farther south, Memphis, Nashville, or central Kentucky end up in the bullseye. That’s a shift that’s entirely within reason. So at this point while the general shape of the rainfall forecast should go unchanged, the exact placement of those bullseyes may waver some between now and Sunday.

And yes, in addition to the flooding, there is a significant severe weather risk, especially on Wednesday.

The Storm Prediction Center forecast for Wednesday shows an enhanced risk (level 3/5) for the area from northeast Texas into the Great Lakes. (Pivotal Weather)

This risk is covered pretty heavily elsewhere. I’ll point you in particular to my friend Alan Gerard’s Substack, which will go in depth on all these threats in the days ahead.