Matt Lanza

Missouri and Illinois deal with flooding, as heat builds up this week across the South and Midwest

In brief: Neither Invest 94L or a potential disturbance in the Gulf are expected to develop this week. Locally heavy rains have fallen in Missouri and Illinois leading to numerous instances of flash flooding. Building heat will make it feel pretty uncomfortable this week across much of the Midwest and South.

Invest 94L

We start out in the Atlantic today, where the tropical wave we’ve been watching is now tagged as Invest 94L. Nothing has changed here, and we expect little to no development out of this feature as it approaches the Lesser Antilles.

Invest 94L looks rather disheveled this morning in the open Atlantic. It has minimal odds of development before reaching the Caribbean. (Tropical Tidbits)

Modeling is in really good agreement that this will plow through the northern Windward Islands, move into the Caribbean, and fall apart. Perhaps we’ll see some added rain and thunderstorm chances in the islands as this moves in, but aside from that, no real impacts are expected out of 94L at this time.

Gulf disturbance

Modeling continues to show a redux of last week’s Invest 93L in the Gulf later this week. A fairly disorganized disturbance will emerge in the Gulf probably on Wednesday and track west. I think this one will enter the Gulf a bit farther south than 93L did, which should allow it to track more toward Texas than Louisiana. Wind shear doesn’t look horrendous, but it will be present. More importantly, the building heat wave north of this disturbance and hot, dry weather in Texas will likely surround this thing with dry air that should limit any development risk.

Rainfall will be locally heavy along the Gulf Coast later this week with the passing disturbance. (Pivotal Weather)

Rainfall will be the primary calling card of this disturbance. Look for locally heavy rain again this week from Florida across the Gulf Coast into Louisiana. The heavier rains may extend a little farther west into parts of Texas by the weekend as well, but major flooding issues are not currently expected.

Overall, odds of any organization are quite low (no models showing anything of note), and again rainfall will be the primary thing to watch here.

Currently, there are no other items of interest in the Atlantic.

Illinois/Missouri flooding

We almost got through yesterday without a flash flood emergency, but one was issued for Fayette County, Illinois just after 11 PM CT on Sunday. That area saw an estimated 7 to 9 inches of rain yesterday from periods of heavy rainfall.

Estimates of over 9 inches of rain yesterday near Vandalia, Illinois. (NOAA MRMS)

Additional heavy rain led to multiple serious flash flooding reports across parts of Missouri, especially just northwest of St. Louis. Flash flood warnings continue in this area this morning. Flooding along the Kaskaskia River at Vandalia, IL is ongoing, and it may approach moderate levels before cresting.

(NOAA)

Some rivers in this region have risen 5 to 10 feet or more in the last 24 hours. The heavy rain risk should shift south and east today, with more risk focused into Kentucky.

Slight risk (2/4) for flooding today across the Quad State region into southern Kentucky and much of Tennessee. (NOAA WPC)

Heat wave

Meanwhile, if it’s not water falling from the sky, it’s water vapor in the atmosphere, and the combination of heat and humidity looks rather stout this week across the Mississippi Valley.

Pockets of “extreme” heat risk dot the region from near Memphis south to near New Orleans by Wednesday. (NOAA)

Widespread high and isolated pockets of “extreme” heat risk per the National Weather Service are expected by Wednesday across the Mississippi Valley and South. Very few record temperatures are currently forecast, but the combination heat and humidity will make it feel pretty rough through the week. More heat is on the way for next week too. More to come.

More flash flooding to discuss as we gloss over some middling tropical disturbances

In brief: A couple areas to watch in the tropics seem unlikely to develop much. Flash flooding hit just outside of DC yesterday and in Iowa overnight. The main flooding threat today will be across central Illinois, Indiana, and southwest Ohio.

Central Atlantic wave not a threat to land

The National Hurricane Center continues with a tropical wave highlighted on their outlook map this morning, but odds of development have fallen to 10 percent. This appears to be unlikely to do much of anything at this point.

The Central Atlantic disturbance is struggling to organize this weekend. (Weathernerds.org)

It’s just not in a prime spot for development, and it’s quite a bit far south. So ultimately, this will likely meet its demise before arriving in the Caribbean as it encounters strong wind shear. Perhaps we’ll see some increased shower chances for some of the Lesser Antilles, but that would be all.

Gulf disturbance next week

Models continue to show that the remnants of 93L will reorient into a new disturbance and do a very similar thing to Invest 93L. A true meteorological deja vu. The new disturbance should emerge in the Gulf by about midweek this coming week. It will then likely track close to the Gulf Coast toward Louisiana or even Texas before coming ashore.

Another Gulf disturbance may make some noise but will ultimately probably move ashore as a rainmaker. (Tropical Tidbits)

Because of how close this will again be to land, it seems highly unlikely that it would develop. Again. Still, this may produce another round of locally heavy rain for the central and eastern Gulf Coast, which you can again see on the rainfall forecast map from the NWS for the next 7 days.

More heavy rain is likely in spots on the Gulf Coast this coming week as another tropical disturbance (unlikely to develop) will produce downpours. (Pivotal Weather)

Certainly something to keep an eye on, but this once again seems like a rain event more than anything.

Flash flood emergency outside of DC on Saturday

The latest in a spate of flash flood emergencies this month occurred in Montgomery County, Maryland, just outside of DC on Saturday afternoon. Rainfall totals of 3 to 4 inches or more, much of which fell in a short time led to widespread significant flooding in the area.

Rain totals north of 4 inches likely fell next door to Silver Spring, MD yesterday, as heavy rain triggered a flash flood emergency. (NOAA MRMS)

Some of the pictures are certainly a bit scary for this area. The runoff caused a very rapid rise on Sligo Creek, which runs through Takoma Park and dumps into the Anacostia River near Hyattsville. The creek set a new record, though it appears that its records only date back into the early 2000s.

Sligo Creek reached a record crest near Takoma Park, though records only date back into the earlier part of this century. (NOAA)

But again, notice the rapid rise there. In a little more than an hour, the creek went from about 20 cfs to 3,000 cfs and rose 7 feet. And while this was certainly a heavy rainfall, it was not the heaviest we’ve ever seen in this region. It just speaks to how quickly flash flooding can overwhelm drainage and watersheds.

Rain chances today

A number of flash flood warnings are currently in effect across Iowa where heavy rain fell overnight to the tune of 3 to 6 inches south of Des Moines.

Rain totals overnight in Iowa exceeded 2-3 inches in many spots with areas south of Des Moines seeing as much as 5 to 6 inches. (NOAA MRMS)

Those thunderstorms have now pushed into Illinois, and as the day goes on, we could see heavy storms develop with daytime heating across Central Illinois and Indiana. A moderate risk (level 3 of 4) for excessive rain is in place from about Terre Haute, Indiana through Springfield and Decatur over to Quincy, Illinois.

(NOAA WPC)

While flash flooding may not be as widespread as it was in Iowa, it does look like we could see isolated pockets from northern Missouri into the Indianapolis, Cincinnati, or Louisville areas that see anywhere from 3 to 5 inches of rain later today. This could produce rapid onset flash flooding in spots. It’s a good day to be alert if you live there or your travels take you to those areas.

You can see the combination of a building heat wave (extreme heat warnings in effect in Kansas and Missouri south to near Memphis) bumping up against flooding risks (green indicating flood watches) in the Midwest. A very hot, swampy type situation for much of the middle of the country today.

(Pivotal Weather)

Heat advisories ring the Southeast today from Oklahoma, Arkansas, and Louisiana, along the Gulf Coast to Florida and up into eastern North Carolina. Expect to see advisories and excessive heat messaging for the next 7 to 10 days across much of the country.

Tropics not totally asleep, as we focus on an extended duration heat wave beginning next week for the Midwest and Mid-South

In brief: A disturbance in the Central Atlantic may try to develop before it dissipates near the Caribbean. Former Invest 93L may return to the Gulf next week as a new disturbance, but no signs of development are showing yet. More flooding concerns continue today in the Midwest and Mid-Atlantic. And some stronger than normal heat remains in the cards next week and into August.

Tropical Atlantic

Yesterday we mentioned the possibility of something low-end in the open Atlantic, and today we’ve got a lemon showing up on the National Hurricane Center outlook.

A disturbance with a 20 percent chance of developing is moving across the Central Atlantic. (NOAA NHC)

This one has about a 20 percent shot at development before it runs into a wall of wind shear in the Caribbean next week. Currently, it’s not a whole heck of a lot to look at. It’s a very broad area of thunderstorms from about 29W to 48W, with the primary disturbance to watch around 36W.

Within a broad area of thunderstorms lies the disturbance being monitored for a low chance of development. (Weathernerds.org)

Wind shear is pretty relaxed out there right now, which could help it to develop, but there is a bunch of dry air and Saharan dust lying just north of this axis of thunderstorms. I would assume if this did develop, as a handful of various models show, it would be brief and lower-end. Semi-permanent high wind shear awaits this once it gets near the islands however, which should spell the end of the road for whatever it can become out there. Perhaps we’ll get an Invest out of this today or tomorrow though, so we’ll just keep an eye on it. But for now, this should not be a worry for anyone.

Ex-Invest 93L’s circle of life

The artist formerly known as Invest 93L is just going to meander around the Southeast this weekend and early next week. Eventually it’s going to be forced south again toward the Gulf and it could re-emerge around late week, likely as a new disturbance. There’s a fair bit of uncertainty as to exactly where this shows back up and in what shape it would be.

Broad signal for a tropical disturbance to re-emerge in the northeast Gulf next week, but not a lot of data suggests it will progress beyond a rain threat right now. (Tropical Tidbits)

But at this time, there’s not any real reliable data showing development. For now, it’s mostly just a curiosity that could bring more rain to parts of the Gulf Coast between Texas and Florida by later next week. Still, we’ll keep tabs on it.

Flooding concerns continue

We saw an interesting assortment of weather on Friday, including a funky, odd system tracking east to west across Southern California bringing some flash flood warnings to the region. MCV’s (or a Mesoscale Convective Vortex) are not especially large, but they can bring some localized intense rainfall to an area as they pass through.

There’s something you don’t see every day — an MCV moving east to west into California towards the Death Valley region:

— Tomer Burg (@burgwx.bsky.social) 2025-07-18T13:48:18.720Z

In fact, we saw some heavy rain in spots between Death Valley (yes it does rain there!) southwest into the San Gabriel and San Bernardino Mountains. There was also a pocket of heavy rain near the Castle Mountains south of I-15 in the Mojave Desert as well.

Rain totals based on radar estimates across Southern California yesterday. (NOAA NSSL)

Additional heavy rain fell in other parts of the Southwest, as it has the last few days, with the area north and west of Las Vegas cashing in, as well as much of southwest Utah and northern Arizona, as well as New Mexico. Given the dry winter this past year in this region, rainfall is certainly welcome.

There were also additional flooding issues in other parts of the country as well, including Evansville, Indiana and (again) Petersburg, Virginia, which had another flash flood warning yesterday.

A broad area of slight flooding risk (2/4) exists from Iowa through the Ohio Valley and into the Mid-Atlantic today. (NOAA WPC)

A slight risk (2/4) is in place over a wide swath of the country for flooding today, covering Iowa, most of the Midwest, and the Mid-Atlantic.

Heat wave cometh

We continue to see plenty of signs of a stout, long-duration heat wave establishing this upcoming week into the following week across much of the Midwest and Mid-South. There aren’t a whole lot of record highs being forecast yet, but there are a number of warm minimum temperature records being forecast. Models continue to indicate some risk of near-record strength to this ridge as it builds.

(NOAA WPC)

Regardless of anything, a wide area is expected to see risk for extreme heat next week and into the beginning of August. Numerous pockets of “extreme” heat risk from the newer NWS product that factors in other things besides just temperature show up by next Thursday and Friday (shown below).

Extreme heat risk is showing up in parts of Mississippi, Arkansas, Tennessee, and elsewhere by late next week. (NOAA)

The combination of these heat risk maps and wet-bulb globe temperatures reaching extreme values in spots means that the heat precautions will be necessary, particularly for vulnerable communities across the Midwest and Mid-South next week. Stay tuned.

Flooding concerns for Louisiana, Virginia, Indiana as heat wave odds increase to close July

In brief: Invest 93L is ashore and not a development risk, bringing more rain and flooding risk to Louisiana and the Gulf Coast. More non-tropical flooding concerns exist today in Virginia and tomorrow in Indiana. And an end of the month heat wave for the Plains, Midwest, and Southeast is looking more and more likely.

Invest 93L: RIP

Shout out to all the purveyors of doom on social media (including some professional meteorologists!) that just had to hype up Invest 93L into something it would never be. Development odds are down to zero percent this morning because the system is over Louisiana now. It’s dead, Jim.

That said, it’s not exactly dead dead. It’s still producing rain, and it remains at least a slight flooding risk (2/4) for much of Louisiana, extreme East Texas, and parts of the Gulf Coast.

A slight risk for heavy rain and flooding exists from Beaumont, TX east across most of Louisiana to the Florida Panhandle today. (NOAA WPC)

There have certainly been some locally impressive rainfall totals in Louisiana, including just shy of 10 inches in the last couple days in St. Charles Parish.

A sampling of 48-hour rainfall totals in Louisiana including nearly 8 inches just north of Morgan City, over 6 inches in New Orleans East, and nearly 10 inches in St. Charles Parish. (NOAA)

I have not seen any reports of major flooding, so that’s good. But let’s see how today unfolds. Some models are still a bit cheeky with rainfall totals in a few spots today, so never declare victory until the storm is officially over.

Rest of the tropics

It looks pretty quiet over the next few days. It is possible that we see something low-end and brief in the open Atlantic early next week, but there aren’t currently any land threats. It’s also possible that the remnants of 93L do a loop around the Southeast and re-emerge again in the Gulf later next week. I’d say that’s something to watch, but much like this week, proximity to land may hinder any development chances.

Flooding risk du jour

If you had northern Virginia on your Summer 2025 flooding Bingo card, congrats, and don’t forget the free space.

A moderate risk (3/4) is in place for the northern Shenandoah Valley in Virginia today for flooding. (NOAA WPC)

Parts of the northern Shenandoah Valley have seen 200 percent of normal rainfall so far this month, with some places seeing as much as 4 to 8 inches of rain since the start of the month. Heavy showers and storms are possible there later today, and this would be a definite area to watch for flooding today. A broad area of slight risk (2/4) surrounds that extending into parts of the Ohio Valley and south into Hampton Roads and the Outer Banks.

Flooding risk du jour Saturday

Tomorrow, I would watch Indiana closest. There is some modeling showing as much as 3 to 6 inches possible, mostly tomorrow in that area. Southern Indiana has seen anywhere from 4 to 8 inches of rain this month as well.

The SPC’s HREF model flagging some significant rain potential in southern Indiana on Saturday. (NOAA SPC)

The HREF model in particular is a little excited about potential heavy rain. The probability matched mean product above suggests that rain amounts of 3 to 6 inches will be possible tomorrow in the heaviest storms mainly south of I-70 in Indiana. I’d pay particularly close attention in the Bloomington through Louisville corridor on Saturday.

Additional rain may follow Sunday and Monday, and flooding risk remains in place there.

Heat wave update

The European ensemble model continues to indicate a decent risk of a record strong ridge of high pressure in the upper atmosphere over the Plains in about 10 days or so.

The percentage of European ensemble members indicating a record strong ridge of high pressure is now up above 30 percent near New Mexico and the Texas and Oklahoma Panhandles. (Polarwx.com)

The Climate Prediction Center continues to indicate a risk of extreme heat starting around July 25th and continuing through the end of the month. There is also now some potential for drought to begin developing and expanding in parts of Kansas.

Odds continue to grow that a significant heat wave will impact the Plains, Midwest, and parts of the Southeast to close July. (NOAA CPC)

Overall, it appears the end of the month may be more about heat than flooding. But we will see.