Matt Lanza

The Atlantic is slowly warming up, while the Desert Southwest is going to heat up this week

In brief: The Atlantic tropics are getting a little busier, but at present none of the potential systems are a concern for land. Meanwhile, the Desert Southwest is going to be at the center of a heat wave this week, which means some extreme temperatures and continued high wildfire danger.

Tropics: Busier but within the realm of what’s typical for August

We’ll start in the Atlantic today. We’ve got two areas highlighted by the National Hurricane Center.

Two areas of interest, including one invest on the board today. (NOAA NHC)

Let’s start closer to the U.S.

Invest 95L

The disturbance we had thought might be of most interest through next week is trying to get its act together off the Carolinas. Invest 95L is attempting to look the part this morning.

Invest 95L is due east of the Outer Banks. It may develop into a tropical or subtropical system before exiting tomorrow. (Weathernerds.org)

Invest 95L is expected to pretty steadily work east-northeast and out to sea. Modeling is in good agreement that this will exit stage right quickly.

Various AI ensembles and the traditional European ensemble all agree that this will quickly turn out to sea. (Google Weather Lab)

Conditions for development should become rather hostile over the next couple days, so this will probably succumb to environmental conditions eventually as it moves out to sea. Bottom line: Decent chance to develop; no threat to land.

Broad 30% area of interest

Looking out farther into the Atlantic today, a very large 30% area has been drawn that covers almost the entire central Atlantic. There’s not a whole lot doing out there at the moment, but it appears that a wave will exit Africa and may begin to attempt to develop by mid to late week. When we look at the European model ensemble picture, we can see that the majority of the 51 ensemble members are doing something out there by later this week, but since they can’t exactly resolve where that might occur, the area of possible interest is rather sprawling.

A large area of possible slow development later this week in the open Atlantic. (Weathernerds.org)

The overall pattern in the Atlantic this week will feature a pretty broad “weakness” in the subtropical ridge east of Bermuda. This should allow for any sort of developing storm to exit. A weaker, disorganized wave may just plod along west northwest.

Friday’s upper air weather pattern probably is conducive to a system moving more NW than W in the Atlantic. (Tropical Tidbits)

You never like to overthink these things too much, so it seems pretty simple. That said, if the forecast weakness ends up stronger or less impactful than predicted today, that could change the overall profile of risk with this wave. For now, it’s probably not a concern for land, but it’s probably also a good idea to monitor its progress later this week.

Behind that, there’s no real defined risk that I can pick up on over the next 2 weeks, but it’s the time of year to keep watching, as I’m sure something will materialize at some point. For now though, the takeaway is that the Atlantic is becoming more active but within the bounds of what’s normal for this time of year.

A Desert Southwest heat wave

The weather pattern has calmed a bit lately, with more moderate temperatures a bit less in the way of extreme rain and such. That said, it does look like the heat is going to crank up this week. When you’re talking about possible temperature records in the Desert Southwest, you know it’s hot. High pressure is going to flex its muscles in that region this week, and in fact, the percentage of European ensemble members showing an all-time record strong upper level high pressure system is well up over 50 to 75 percent this coming week (Wednesday).

The Desert Southwest is going to be a blast furnace this week. (Polarwx.com)

That doesn’t guarantee that we’ll see a record, but it sure suggests that whatever this is is going to be extreme. In fact, we’re already seeing numerous record highs or near record highs being forecast in the Desert. Phoenix is expected to hit 117° on Thursday, which would break a daily record by 5 degrees and match the all-time August record high temperature last set in late August 2023.

Several record high temperatures are forecast to be approached or exceeded this week in the Desert Southwest, with Thursday shown here. (NOAA)

The 111° is Tucson is only one degree shy of the August record as well.

We may see more than one record fall this week in Phoenix and Tucson.

Forecast temperatures for the next 7 days in Phoenix. (Weather Bell)

Broadly, the Southwest will also experience multiple days of records threatened. More importantly, it looks dry this week with most moisture limited. Any rain will be limited to the Plains or perhaps deep into Mexico.

Rainfall over the next 7 days is expected to be virtually non-existent in the Southwest. (StormVista Weather Models)

This will likely lead to continuing wildfire concerns, and critical fire danger is forecast for Utah tomorrow and Tuesday. Red Flag Warnings are already posted for both days.

Several wildfires, including the now 60,000 acre Monroe Canyon fire are burning throughout Utah, a situation that may worsen some Monday and Tuesday. (State of Utah)

Conditions may be a little less extreme in Arizona for wildfires, but it’s possible that Red Flag Warnings are hoisted there too this week. Either way, the West is already a bit of a tinderbox, and this week will do nothing to help that situation.

More heat to open August, while we look back at July’s variable rainfall story across the country

In brief: Today we discuss the have too much’s and have too little’s of rainfall from July. We also briefly look at July’s temperatures. Meanwhile, August will begin quiet in the Atlantic, noisy in the Pacific, and just hot for many.

Recapping July’s rainfall

Apologies for some of the later day posts this week. Work obligations just take priority! Let’s look back at July real quick.

Despite all the flash flooding issues in July, the country saw a mixed bag overall, with the Southeast and New England generally drier than normal. The Southwest is a little choppier due to low average rainfall totals. (High Plains Regional Climate Center)

The areas that saw the most rainfall relative to normal last month included northern California and eastern Oregon, as well as the northern Rockies, Iowa, northern Missouri, Central Texas, and North Carolina and Virginia. Even with above normal rainfall in Oregon, some significant wildfires occurred there in July. Mount Shasta in California had its 5th wettest July on record.

Working east, it was the 7th wettest July on record in Glasgow, Montana and Norfolk, Nebraska. In Des Moines, Iowa July 2025 is the new wettest July on record. The capital of Iowa saw 10.62 inches of rain last month, just edging out July 1958.

Click to enlarge to see a number of rivers in Iowa that are near or in flood at present. (NOAA National Water Center)

Numerous rivers are in flood or near flood across Iowa after such a wet month. Waterloo, Iowa had their 7th wettest July, while Moline, Illinois finished in 5th place. Kansas City ended up in 9th place.

In Texas, Austin finished 9th for July in precip. Obviously some parts of Hill Country likely finished higher than that, not just because of the July 4th tragedy but because it was a wet month overall. In Waco, it was the 7th wettest July. Moving east, Richmond, Virginia had their 8th wettest July, while Greensboro, North Carolina finished in 9th place.

On the opposite end of the spectrum, it was the 11th driest July on record in Manchester, NH, while it was the 4th driest July in Bangor, Maine. Meanwhile, in Seattle it was the 6th driest July on record with a mere 0.01″ of rainfall. Not that July is known to be a wet month in Seattle, but the average is still about 0.6 inches. In Eugene, OR July 2025 joined 12 other Julys with no rainfall back to 1893.

Phoenix saw less than a quarter-inch of rain last month, and Las Vegas only saw about 0.02 inches. The first megafire of 2025 in the Lower 48 is ongoing in Arizona. Typically, Phoenix and Vegas pick up about a half-inch to an inch of rainfall, less north, more south due to the monsoon. With a somewhat sluggish July in the precip department in Arizona, Utah, and Nevada, we are seeing wildfire issues instead. The Dragon Bravo fire has burned over 115,000 acres and is continuing to expand. This fire is responsible for the terrible damage earlier this month in the North Rim of the Grand Canyon.

The Dragon Bravo fire on satellite imagery from this past Wednesday in northern Arizona. The Monroe Canyon fire in Utah can be seen near the top of the image. (College of DuPage)

Farther north, the Monroe Canyon fire is burning in Utah over 55,000 acres so far. This one appears to be growing significantly and has forced evacuations recently.

As far as heat goes, that’s a topic that we’ll perhaps dive into a little more on another day. But suffice to say, it was a hot month nationally.

Only Central & Western Texas and the Southwest were slightly below normal in July. The rest of the country was near or above normal, with much above normal in the Ohio Valley and Appalachia. (High Plains Regional Climate Center)

For Indianapolis, it was the hottest July since 2012. It was 10th hottest on record in Pittsburgh. In Syracuse, it was the third top 10 hottest summer since 2020.

Dog days of summer are here

Anyway, onto August we go.

Heat will be the main story for the beginning third of August. (NOAA WPC)

The main weather issue over the next 10 days or so will be heat. Yes, there will be pockets of strong storms and flooding around, but heat is going to begin to expand again next week from the Southwest into the Plains with a major ridge of high pressure setting up shop. We’ll probably see record temperatures at times from Arizona through Texas next week. August being August.

Tropical update

The tropics remain calm for now. I suspect we’ll have more to discuss next week. The Pacific is a beehive of activity, but none of these storms are likely to impact land at this time. Iona is heading deeper into the open Pacific and weakening. Gil should briefly become a hurricane before weakening as it passes well north of Hawaii.

The Pacific is buzzing. (NOAA NHC)

The area behind Gil could become a little more interesting to watch as it relates to Hawaii, but that’s days away so it’s more likely to do nothing than impact Hawaii at this time. We’ll keep an eye on things.

Mid-Atlantic flooding risk dialed in for today, while we peep the first half of August in the tropical Atlantic

In brief: A moderate risk (3/4) remains posted today for flooding between Washington, DC and northern New Jersey with isolated 4-to-7-inch totals expected. The tropics remain quiet, and heading into the first half of August, it’s not apparent that things are going to dramatically increase. We’ll keep watching.

Fairly brief update today, but let’s get to it.

Flooding risk in the Mid-Atlantic

There continues to be a moderate risk (3/4) of flooding today in the Mid-Atlantic region.

A moderate risk for excessive rainfall exists from just south of DC to just west of New York. (NOAA WPC)

Modeling continues to strongly suggest the potential for isolated pockets of 4 to 5 inches or more of rainfall across the moderate risk area. Potential does exist for perhaps up to 7 inches of rain in some really isolated spots. Many areas will be fine today, but the entire region is at risk for something a little more serious, hence the moderate risk.

HREF model probability-matched mean rainfall forecast for Thursday showing pockets of high rainfall. (NOAA SPC)

Basically, it’s a good day to make sure that you plan around the rain in the region. Maybe hang tight at your location for a bit if it’s raining heavily. Have a way to receive flash flood warnings. And do your best to never drive through a flooded road, as the water is often deeper than you realize.

Tomorrow’s rainfall risk shifts southward into the Southeast, mainly the Carolinas.

A slight risk (2/4) of heavy rainfall and flooding exists in the Carolinas for Friday. (NOAA WPC)

That risk will probably hold steady in that area for Saturday as well.

Tropics still mostly benign

Another day with no tropical threats on the map from the National Hurricane Center today. As all the thunderstorms in the Southeast begin to push offshore, there is a very, very slight risk that something may try to briefly spin up and head out to sea from there. But those odds look quite low.

Overall, the Basin looks about average for this time of year right now. Over the next couple weeks, I’m not convinced it’s going to get more favorable. Of course, given that climatology begins to ramp up in August, that should still mean we see something at some point in the next 2 to 3 weeks. That’s just a given. But in terms of getting a lot of activity, significant activity, etc., I’m not sure I see the background state of the Atlantic cooperating in a significant way right now.

If you want to look out far in time, we can grab the European model’s subseasonal outlook for tropical storms.

The odds of a tropical storm per the Euro weeklies yesterday is highest off the East Coast in mid-August. (ECMWF)

The odds of a tropical storm in mid-August (we’re looking at the week of August 11th here) aren’t exactly strong. Some European model data suggests perhaps something could emerge off the Eastern Seaboard, but the odds at this point remain below 30 percent, or close to normal for this time of year. Conditions may become a smidge more favorable by later August, but again, that should be expected in a normal hurricane season.

Increasing flooding threat in the Mid-Atlantic for Thursday

In brief: An upgrade to a moderate risk of flash flooding was triggered for Thursday in the Mid-Atlantic, including DC, Baltimore, Philly, and much of Jersey. The tropics remain quiet, but heavy rain is likely to pester the Southeast heading into next week.

For the latest on the tsunami and major earthquake last night, I’m going to point you elsewhere. There are plenty of good seismologists and geologists out there that can explain much of what happened better than this meteorologist. A number are active on various social media platforms, good people to seek out to understand this stuff. Meteorologists are often the ones used to explain various earth and astronomical events, often because we’re just generally decent science communicators. But there are so many others out there that are better at those events than us. You don’t want an astronomer explaining molecular biology to you, so no difference here.

Mid-Atlantic flooding risk Thursday

I want to start our weather discussion this afternoon with some updated news. The Weather Prediction Center has upgraded tomorrow’s flash flooding risk in the Mid-Atlantic from slight (2/4) to moderate (3/4). Data today has come in pretty aggressive with potential rainfall tomorrow between northern New Jersey and northern Virginia.

(NOAA WPC)

This risk area includes Washington, DC, Baltimore, Philly, and most of the I-95 corridor southwest of New York City. Per the WPC discussion, with the area lying sort of close to a couple key meteorologically supportive areas for heavy rainfall, this sets the stage for impressive rain totals, some training thunderstorms (storms that repeatedly travel over the same locations), and an urban area that is naturally prone to flash flooding. Flood watches have been issued today for Thursday’s storms.

Looking at model data, it’s pretty clear that while the entire region will see some rain, the biggest concerns will be in isolated pockets between northern Virginia and northwest New Jersey.

The SPC’s HREF model shows a signal for isolated pockets of 5″ or more of rain on Thursday in parts of the Mid-Atlantic. (NOAA SPC)

The HREF model shown above which is an ensemble of a few high-resolution models produces a product called the probability-matched mean, which tends to flag areas of higher risk and what those totals could be. And indeed on this morning’s run, it shows legitimate potential for 5 inches or more in pockets around DC and Baltimore, as well as near and north of Philly. Exactly where those higher totals establish is very much up in the air this far out. But this is why the moderate risk covers a broad area in parts of the Northeast Corridor. Even in areas under the lesser slight risk (2/4) should take heed that heavy rain is possible, if not likely tomorrow, including southern New England and parts of New York State south of Albany and into the Catskills.

Bottom line: Flooding potential is very elevated tomorrow in the Mid-Atlantic, so stay on your toes and be alert.

Tropics remain calm

All remains quiet in the Atlantic with no highlighted areas anywhere in the Basin for the next week. We continue to see “noise” on the modeling off the Southeast coast next week, but any system would likely pull east out to sea. Nothing to home in on beyond that right now.

We will see heavy rain as a result of the pattern setup along the Southeast coast. This is probably why the models are latching onto some sort of low-end potential in that region next week. Anyway, the rain will bring probably 3 to 5 inches of liquid to much of the Southeast or southern Mid-Atlantic.

Heavy rains are likely over the coming days in the Southeast and near the coast, perhaps to the tune of 3 to 5 inches or more. (Pivotal Weather)

The heaviest rains look to be on the Carolina coast with 4 to 6 inches possible from the Outer Banks south to Savannah.