What needs to change for more frequent cool fronts in Houston?

In brief: Houston will see more of the same through Monday or so, with temperatures running around 7 to 10 degrees warmer than normal and lots of sunshine. We turn up the humidity after Tuesday with increasing rain chances, though the best rain chances may end up to our north. Halloween evening will be warm with at least some chance of rain.

40 years ago today was Houston’s (official) 4th wettest day on record, with hundreds of flooded homes and 10 inches of rainfall. The culprit was a stalled out cold front and several prior days of rain that had primed and saturated the ground. The current forecast has nothing remotely resembling rain until next week.

Today through Sunday

The next few days should feature more of the same in Houston. Expect plentiful sunshine, generally pleasant mornings in the 60s, and afternoon highs in the upper-80s, about 7 to 10 degrees warmer than normal and not far from records. Each morning could see pockets of dense fog in the area, so just be mindful of that. A reinforcing shot of drier air may help shave off a few more degrees on morning lows tomorrow or Sunday, but that should be the only evidence of it that we notice.

Monday & Tuesday

We begin to slowly transition here to a more humid type pattern. Look for daytime highs to stay in the mid to upper-80s, with nighttime lows in the 60s to low-70s. More sunshine is expected, but I would not entirely rule out an isolated shower on Tuesday.

Rest of next week & Halloween

The forecast becomes pretty straightforward in a generic sense after Tuesday. We will have clouds, sun, high humidity, and a chance of showers developing. Look for much warmer nights and mornings and slightly less hot afternoons. The highest chance of rain will probably be Wednesday or Thursday. Yes, there is a chance of rain on Halloween, but it remains much too early to get specific. We are confident that it will be a warm evening though.

The forecast of rainfall through next Friday morning shows the best chances to our north. (Pivotal Weather)

I am a little concerned that the best rain chances will elude us to the north after Wednesday, but we still have time to watch this. Rain totals through Thursday are shown above, as forecast by the NWS. Expect some variability here with some places seeing minimal rain and others seeing perhaps an inch or two.

Next cold front?

There continues to be model evidence of a cool front after next weekend. Exactly how strong and when exactly it arrives remains to be seen. I’d still keep my expectations low, but the signal has remained at least!

Why the struggle to cool off?

Yesterday, Eric noted how the 6 to 10 day outlook showed warm temperatures leading into November. Now, as noted we are hopeful for a cool front somewhere around day 10 or so, but it will be unlikely to deliver actual *cold* air. In order to get true cold here in Texas, it usually either has to come straight outta Canada and down the Plains, your typical ‘norther. Or it has to be manufactured more locally, usually by clouds, rain, and chilly but not necessarily truly cold temperatures. That latter scenario happens to us sometimes in later November through March most often. This time of year, for hints of something beyond just an autumn tease or a setup for more frequent cool fronts, we would probably need to see cold air building up in western Canada.

The overall pattern setup in early November is not one that supports cold air in Canada, thus making it harder to get stronger, frequent cold fronts in Texas. (Tropical Tidbits)

If we look at the Euro ensemble forecast of jet stream winds on the maps above, you’ll notice what is basically a straight shot of green, yellow, orange, and red from China and Japan to southwest Canada. This is the core of the jet stream, and when it is doing this (extending across almost the entirety of the Pacific into Canada), it basically limits how cold it can get up there. It keeps weather active, it ushers in storms, but it never allows any cold to settle. Without that, we kind of have an elevated floor for how cold it can realistically get down here in Texas, as any cold coming out of Canada would be weak to begin with and continue to modify milder as it came southward. This can all change quickly, but there’s absolutely no sign of it right now in any real modeling. Until that gives, expect milder than normal weather to continue more often than not. We’ll still have periodic fronts, but they’ll mostly just reinforce comfortable humidity levels more than anything. Certainly not a bad thing, but it would still be abnormally mild.

Houston to remain warm, to very warm, into early November

In brief: Houston will continue to see very warm days, with highs generally in the upper 80s, for the rest of the month into early November. The only difference is that the modestly lower humidity we have seen this week will increase next week, and things are going to feel really humid for this late in the year. Rain chances remain possible later next week, but we’re unlikely to get the widespread drought relief we need.

Thursday

Calm winds and temperatures down near dewpoints in the lower 60s this morning are creating conditions to produce at least some patchy fog across parts of the area, but it will recede as temperatures warm up. We’re going toward the mid- to upper-80s for most locations today, with sunny skies and light easterly winds. Dewpoints will be low enough that the air feels at least somewhat dry outside. Low temperatures tonight will drop into the mid- to upper-60s for most locations, with the coast warmer as usual.

Friday’s high temperatures will be toasty indeed. (Weather Bell)

Friday

We’ll be a bit warmer on Friday, with much of the area in the upper-80s and a few locations potentially hitting 90 degrees. Sunny skies will prevail. The air will also feel a bit more humid, so this will be a pretty warm day overall. Lows on Friday night will only drop into the upper 60s.

Saturday and Sunday

Dewpoints drop back slightly for the weekend, so the air should again feel slightly drier. Days will still be quite warm, in the upper 80s for most locations. However, nights will be back into the mid-60s for most of Houston away from the coast. Skies will be almost uniformly sunny, so you should have no concerns about outdoor plans, except for atypical heat for late October.

Texas, and the eastern United States, will be very warm next week. (Pivotal Weather)

Next week

We’ll see a continuation of warm, sunny days to start next week, with highs again in the upper 80s on Monday and Tuesday, and clear nights with lows in the upper 60s. However, the onshore flow should really start blowing and going at some point on Tuesday—we may see some fairly pronounced southerly winds—and this will act to boost humidity. We’re then likely to see partly cloudy and humid days during the second half of next week, with highs remaining in the upper 80s and nights in the low 70s. This is really incredibly warm for late October (including Halloween) into early November.

The only upside is that rain chances will finally return to the forecast by Wednesday or so. However, the overall likelihood of rain probably remains in the 30 percent range. In his post yesterday, Matt mentioned the possibility of a cold front by around next weekend, and there’s still a healthy chance of a front by Sunday (November 3) or Monday, but it’s something I would consider far from locked in.

Houston’s next couple weeks of weather should be a play in 3 acts

In brief: More of the same is expected over the next few days in Houston, with cool-ish mornings and very warm afternoons, along with a good bit of sunshine. The weather pattern changes for a time next week toward humid with rain chances. Then, perhaps we can await our next front.

About 800 miles separate the two portions of Texas that have done well in the rain department this month: The mouth of the Rio Grande and the tippy top of the Panhandle. New Mexico has outperformed Texas, even with some serious flash flooding there recently.

Almost all of Texas has been dry this October. (High Plains Regional Climate Center)

But in general, we are far from alone right now in this dry pattern. The next couple weeks will bring us more of the same but also some potential for change, particularly next week. I think looking at the European ensemble for low temperatures the next two weeks shows how the pattern splits into 3 differing acts of weather.

The 50 member European ensemble gives us a three-part flavor to the weather over the next two weeks. (Weather Bell)

Act I: The stable period through Sunday

Over the next several days, things will be pretty calm. We can expect daytime highs in the upper-80s, just a couple degrees shy of daily records. But if you want some autumn flavor, the mornings will remain fairly cool, in the 60s. These temperatures are still solidly at least 8 to 10 degrees warmer than usual. Rain chances will remain nil. We will get a weak reinforcing shot of drier air Friday that should extend this weather through at least Sunday and possibly Monday.

Act II: Revenge of humidity and rain chances

Next week sees a change. We’ll have both more unsettled weather and increasing rain chances, as well as much more humidity. Overnight lows will likely shift into the low-70s, about 10 to 15 degrees warmer than normal, while daytime highs will hold steady or even fall a few degrees due to clouds and rain chances.

I think we want to be realistic about rain chances next week. In a drought, sometimes you find ways to fail, and while I would still expect at least an inch or so of rainfall from scattered thunderstorms next week, the heavier rains, the 2 to 4 or 5 inch totals will probably be confined to a narrow corridor somewhere in the area along or northwest of highway 59. Something we will continue to watch. The European operational model shows this well below as a possible example of what could occur.

European operational model rainfall forecast for next week shows a narrow band of 2 to 5 inches of rain, with most other places seeing 1 to 2 inches or less. (Pivotal Weather)

Regardless, we will see just a warm, humid, un-autumn-like week next week.

What this means for Halloween remains partially unclear. There will almost certainly be a chance of rain, but it will almost certainly also be warm. So plan for warm right now, but check back with us on the rain chances which may not become clear until early next week.

Act III: Additional autumn?

After next week’s pattern shift, we could see a return to something more typical for autumn. I would say there’s probably a 40 to 50 percent chance of a meaningful cold front around next weekend. The exact timing is uncertain, but there’s enough signal in the models for us to think there’s a decent chance. We’ll keep watching.

October is typically Houston’s second wettest month—this year, not so much

In brief: Today’s post discusses why the month of October is often one of Houston’s wettest months of the year, but definitely is not in 2024. We look at our continuing warm daytime temperatures through the weekend, and the possibility of finally seeing some rain next week.

State of play

With high pressure more or less in place for the forecast period, we’re going to see warmer than normal days into early next week. However, the overall flow will be somewhat drier, so we’re going to see dewpoints lower than is customary in Houston. The net effect is that daytime temperatures will warm more rapidly, but nights will be a bit cooler than we might otherwise expect. Unfortunately, the overall atmospheric pattern will remain dry through the weekend as well, continuing our very dry October.

Average rainfall, by month, in Houston. (NOAA)

To date, the city has recorded 0.0 inches of precipitation this month. That’s surprising, because October is often one of the wettest months of the season. The historical average is 5.46 inches of rain, which ranks as the second wettest month, behind only June. Why is this month often so wet? We sometimes see late-season influxes influxes of tropical moisture earlier in the month, and often the fronts sweeping down in later October bring storms with them. We have seen none of that this year.

Tuesday

High temperatures today will reach the mid-80s for much of the area, although a few inland parts of Houston may push into the upper 80s. Skies will be mostly sunny, with a light easterly wind. Low temperatures tonight will drop into the mid-60s.

Wednesday, Thursday, and Friday

Skies will be mostly sunny throughout the week. High temperatures will depend on your location, ranging from the lower 80s near the coast, with the upper 80s in much of Houston, and pushing 90 degrees further inland. Days will be hot, but with dewpoints in the upper 50s and lower 60s, the air will feel modestly drier. Overnight low temperatures drop into the 60s for all but the coast.

The forecast is the same. (Weather Bell)

Saturday and Sunday

You guessed it, more sunshine. Highs will remain mostly in the upper 80s, with lows in the 60s. The chance of inclement weather is basically zero, so if you have outdoor activities planned, you can feel pretty good about them. Provided you bring sunscreen, of course.

Next week

The sunny pattern continues into Monday, after which time we are likely to see the atmosphere become a bit more disturbed. This should lead to the development of some clouds by Tuesday, and some decent rain chances by Wednesday. I don’t want to over-set expectations, and no one should be expecting a few inches of rainfall to put a dent in our emerging drought. But the very dry pattern should finally begin to break during the second half of next week. The models are all over the place in terms of temperatures, so I don’t have much confidence in the weather for Halloween yet. If pushed, I’d guess that high temperatures are somewhere in the lower-80s, but I feel like that could be a trick.