There are a few (very slight) hints of fall in the forecast

In brief: In today’s post we discuss the hints of forthcoming fall weather in our forecast, and also discuss the possibility of additional weather balloons in Texas. For our forecast, Monday looks to be quite hot, but with lower humidity After today there will be a smattering of rain chances all week, with the weekend looking cooler after a weak front (probably) arrives.

Signs of fall and weather balloons

I wanted to hit on a couple of notes this morning. First up is the realization that this is the final week of August, and a period when we often see high temperatures in the 100s in Houston. For this week Monday, especially, looks to see hot weather. But one of the reasons for this is that we are seeing an influx of drier air, which is a harbinger of stronger fronts that will be possible in a few weeks’ time. This afternoon we may see dewpoints drop into the upper 50s in Houston, and while this is not super dry, it is significantly less humid than normal for late summer. This drier air will allow afternoon highs to spike into the upper 90s. Additionally, we have the prospect of another weak front sagging into Houston this coming weekend. Now these August fronts don’t carry much oomph, but they pave the way for the possibility of more substantial fronts in September. Also, we might get some lows in the lower 70s out of it, possibly even upper 60s for far inland areas. So yes, it’s still summer out. But if I squint, I can see change on the horizon.

HRRR model forecast for humidity on Monday afternoon. (Weather Bell)

I also want to mention an editorial that appeared in the Houston Chronicle last week regarding the devastating Central Texas flooding in early July. The editorial correctly notes a paucity of weather balloon soundings over Texas (something we’ve often talked about here), and suggests that as part of their ongoing special session, Texas lawmakers consider creating a network of weather stations to better monitor conditions across the state, including setting up additional weather balloon launches on a daily basis. As a forecaster, I can say that this would definitely improve our ability to predict the most dynamic and impactful flooding events such as that which occurred near Kerrville.

Monday

As noted above, we are seeing an influx of drier air today. This should lead to a hot, mostly sunny day for the region. Expect highs in the mid- to upper-90s with a few far inland areas possibly toying with 100-degree weather. Overall humidity should be lower, however. So if you’re one of those “it’s not the heat, it’s the humidity people,” today is your day to shine. Rain chances are near zero. Lows tonight will drop into the upper 70s.

Tuesday, Wednesday, and Thursday

A pattern change will see slightly more unsettled weather move into the area for the mid-week time frame. Overall rain chances will be on the order of 30 to 40 percent daily, and for the most part accumulations should slight, on the order of a tenth of an inch of rain, or two. A slight increase in cloud cover should help moderate temperatures a bit. Highs should be in the mid-90s for most locations. The dry air will be long gone, so expect ample humidity. Lows will drop into the upper 70s for most.

NOAA rain accumulation forecast for now through the weekend. (Weather Bell)

Friday, Saturday, and Sunday

A weak front will approach the area on Friday, and likely push into the metro area on Saturday. The net impact of this should be to drive up rain rain chances to about 50 percent daily. Again, we are not looking at anything too special regarding accumulations, probably just tenths of an inch for the most part. But there could be a few stronger showers that bring a total of 1 inch or more to some areas near the coast by the end of the weekend. Highs on Friday should reach the mid-90s before falling to around 90 degrees this weekend with a few more clouds and slightly cooler air. Lows this weekend could drop into the low to mid-70s. Again, this is not chilly by any means, but a nice harbinger of what’s to come this fall.

Next week

The overall pattern next week should see continued highs mostly in the low- to mid-90s, with decent reain chances. Knock on wood, but I’m not seeing any sign of the early September spike in daily highs that the region sometime experiences.

Flash flooding a possibility Friday afternoon with stubborn, slow-moving storms in the Houston area (Updated)

In brief: We are pushing out a Stage 1 flood alert for today based on developments since this morning. Locally heavy downpours will almost certainly cause some street flooding around the area, primarily of the nuisance variety, so use caution the rest of the day if out and about.

Update: The flash flooding threat has mostly ended. We will go back to normal, ending the flood scale alert and referring you to our Friday AM post for the weekend outlook.

We’re going to update things today, as it appears we’ve got some sluggish movers out there. We’ve already seen a couple flood advisories this morning, and some chunks of the area have received 1 to 4 inches since Tuesday.

Rainfall since midday Tuesday. (NOAA MRMS)

As such, we’re going to fire up the flood scale for Stage 1 today. I would bank on at least a few areas seeing flooded streets today that may inconvenience travel as the afternoon wears on. So, use caution out there today, particularly in areas of persistent downpours. Off and on rain and thunder is likely to persist and maneuver around the area through early evening before hugging the coast at times again overnight, possibly spreading inland a bit again as well.

Stage 1 in place for the rest of today.

So use caution out and about, and we’ll let you know if things should escalate further, though we don’t believe that to be so today. Our next update will be planned for Saturday morning unless the situation warrants otherwise.

Tolerable, not terrible August weather continues for Houston

In brief: Another round or two of showers and storms will pelt many parts of the Houston area today, with some locally heavy rain possible. Rain chances will start to slow this weekend into early next week before the next round of rain chances kicks off around midweek. There are no current tropical concerns for the Houston area.

Yesterday’s storms were relatively squirrely, especially down in Brazoria and southern Fort Bend Counties. There was a 66 mph wind gust reported from a CenterPoint weather sensor at Brazos Bend State Park. Fascinatingly enough, the radar looked rather innocuous with the storm at the time, but some strong wind gusts elsewhere, including nearly 50 mph just west of Damon seem to back that reading up. That’s just the thing with storms this time of year in Houston: If you catch one at the wrong point in its life cycle in the wrong way, it can produce some pretty quick, short-lived but nasty impacts.

Today

Already today we’ve seen plenty of thunder and some wind gusts up near 50 mph near San Luis Pass. As of this writing, the heavier storms are all offshore, with some isolated downpours and lightning outside the Beltway in western Harris County back through Sealy and Columbus.

(RadarScope)

As the day goes on, we may actually see things calm down a bit for a time before ramping back up again this afternoon or this evening. I’m not entirely confident on the timing of the next wave; some modeling is quick and quite aggressive with coverage of the next wave of showers as early as late morning. Others hang development back until late afternoon. But we do know a second wave of scattered downpours is likely later today. Expect a very sporadic pattern of coverage with some places seeing squat and others seeing as much as 2 to 3 inches in short order.

Weekend

A continued chance of showers and thunderstorms will be with us on both Saturday and Sunday, as is typical for August. We do think coverage and some of the intensity of the storms will wane a bit on both weekend days, with perhaps Sunday having even less coverage than Saturday. We may see another rude early wake up in spots on Saturday morning as some nocturnal storms could pop up after midnight between Houston and the coast. Then I think we’ll see a summer pattern of mid to late afternoon isolated to scattered downpours resume.

Look for highs in the mid-90s, with a few isolated upper-90s possible.

Monday and Tuesday

We think things will be similarly subdued like Sunday to start next week. Rain chances certainly are not zero, but they’ll remain lower. Highs should again be in the mid-90s.

Midweek next week

We should see another boundary drop in or develop over the region around midweek next week. This should mean an increase in shower and thunderstorm coverage once again. Look for cooler daytime highs as a result.

Rain forecast through next Thursday. (Pivotal Weather)

Total rainfall between today and next week is likely going to be around 1 to 3 inches near the coast, with lesser amounts inland. Isolated higher amounts are possible anywhere in the area, and yes, some isolated places will see lower amounts too.

Tropics

The map currently favors us for the most part.

(NOAA/NHC)

Of the activity out there today that we’re monitoring, only Invest 99L is worth keeping an eye on. No reliable model guidance is bringing it to the Gulf, but just out of respect for the calendar and history, it’s important to just check in and see if southern tracking waves like this one heading for the Caribbean can survive enough to get closer. Even if it were to do that, I’m not sure that the upper pattern would allow it to come north much, if at all. So either way, this probably ends up buried in Central America ultimately. But we’ll babysit it anyway. Other than that, you can continue to assume the brace position as we navigate the final 5 to 6 weeks of our peak hurricane season. We’re all just trying to get to the finish line.

Healthy shower chances today and Friday, and August should end in about the best way possible for Houston

In brief: Today’s post discusses the favorable setup for rain on Thursday and Friday in the greater Houston area, with the best conditions closer to the coast. Rains should diminish some this weekend, with Sunday looking especially sunny. Overall our temperatures look moderate for the rest of August.

A favorable setup for rain

There’s a lot of support for showers and thunderstorms to develop in our region today and Friday, with better coverage especially during the afternoon and evening hours. The atmosphere is laden with moisture, we have a nearly stationary boundary (essentially a dying front), the sea breeze, and plenty of daytime heating. In such an environment we are likely to see widespread showers, and within that some stronger and possibly severe thunderstorms.

The most likely time for activity is from mid-afternoon through the early evening hours, and the most favorable conditions will be closer to the coast (essentially, south of Interstate 10). Rain amounts will be widely variable, with some areas picking up a quarter of an inch, and other areas possibly 3 or more inches through Saturday. As a result we will probably see some ponding on roadways, and perhaps a few isolated flooding issues. Although we don’t anticipate major disruptions from these rains, you’ll want to check the radar before heading out. Slightly higher pressures should begin to limit shower coverage by Saturday.

NOAA rain accumulation forecast for now through Saturday. (Weather Bell)

Thursday

Overall rain chances are about 60 percent today in the region, although I’d go higher than that closer to the coast, and less for inland areas. We will see partly sunny skies, with light north or northeast winds. High temperatures for most locations will be in the mid-90s, but temperatures will quickly drop into the 80s, or possibly even upper 70s, within showers and thunderstorms. Humidity will remain high. Lows tonight drop into the upper 70s with an ongoing (albeit lower) chance of showers.

Friday

This is probably the day when most people will see the most rain, so again prepare for the possibility of some brief disruptions. With increased cloud cover, expect high temperatures in the vicinity of 90 degrees. Winds will be light. Lows on Friday night will drop into the upper 70s for most locations.

Saturday and Sunday

The first half of the weekend will see some lingering clouds and showers. Highs on Saturday, accordingly, should reach the lower 90s for most locations. But we should definitely be on a downward trend in terms of amounts, as high pressure begins to build to the west of the region. Sunday should be mostly sunny, with rain chances only in the vicinity of 20 percent. Expect highs in the mid-90s. So for beach and pool activities, Sunday is the pick of the litter.

These are pretty reasonable “wet bulb globe temperatures” for Houston in late August. (Weather Bell)

Next week

To start next week we will remain in a pattern of mostly sunny weather, with highs in the low- to mid-90s and lower end rain chances. However by Wednesday or so we may start to feel the impacts of another decaying front. This probably will bring some increased rain chances, although to what extent it’s difficult to say. High temperatures also may hold somewhere in the vicinity of 90 degrees for much of Houston, which is a pretty great way to end August in these parts.

There’s plenty to look at in the tropics, but nothing that is imminently bound for the Gulf. (National Hurricane Center)

The Atlantic tropics

Hurricane Erin is passing almost directly between Bermuda and the Outer Banks this morning, remaining far enough offshore to avoid bringing catastrophic damage to both locations. After some intensification on Tuesday, it is also beginning to weaken. There are other storms that may form in the coming days, but I’m happy to report that we see no imminent threats to the Gulf at all. Again, this is a pretty great place to be, tropics-wise, as we get toward the end of August.