Matt Lanza

Spectacular autumn weekend ahead for Houston, while the tropics show no quit

Good morning, and it’s a cool one again across the area. We have mostly 40s and some low-50s peppered in everywhere.

Temperatures are generally in the 40s and low 50s across most of the area this morning, a cool start! (NOAA)

Yesterday began one of the coolest but nicest stretches of weather for us in a long while that will continue through the weekend.

Today & weekend

Look for simply spectacular autumn weather all weekend long. We’ll top off in the upper-60s today with wall to wall sunshine. Look for low-70s tomorrow and mid-70s on Sunday. Morning lows will generally be in the mid-40s to mid-50s through Sunday. Winds should be lighter than they’ve been the last couple days.

For trick or treating, look for comfortable weather this year. Expect upper-50s to low-60s north and mid to upper-60s or a tick or two warmer in the city of Houston and points south.

Early next week

A reinforcing shot of drier, cooler air will arrive Sunday evening, so you’ll notice offshore winds kick up again later Sunday and on Monday. Look for cooler temperatures again Monday with highs in the 60s for most of us. Tuesday should see low-70s with lighter winds, and Wednesday likely sees mid-70s. Morning lows look cool on Monday and especially Tuesday. Look for upper-40s or low-50s Monday morning and mostly 40s on Tuesday morning.

Morning lows on Tuesday will bottom out in the low to mid-40s most places. (NOAA forecast via Weather Bell)

Look for some high clouds and warmer temps to return on Wednesday, and that heralds a pretty substantial and possibly lengthy warm-up that may linger through next weekend and into the following week.

Tropics

We knew 2020 was going to be an active hurricane season, but the absurdity of it all has still been surprising. It’s really been non-stop in the Gulf, either dealing with a threat or looking ahead to the next one since Hanna struck South Texas back in late July. Hurricane Zeta may have been the most impressive of them all for how anomalous it was.

Zeta is the strongest known storm back to at least 1850 in the western Gulf this late in the hurricane season.

Zeta peaked at 95 kts. (and I wouldn’t be shocked to see it reanalyzed at 100 kts. (115 mph) in the offseason), which shatters the record of 75 kts. that far northwest in the Gulf for this late in the year. More impressively, Zeta’s intensity ramped up 40 kts. (45 mph) in 26 hours.

The previous record from late October onward was somewhere between 10-21 kts. In that respect, Zeta is in a league of its own. Hurricane season technically runs through November 30th, but in the western Gulf, we usually shut down in mid-October. Zeta obliterated that paradigm. Why? Well, it’s not that the Gulf is super-warm. In fact, Zeta continued steadily strengthening over cooler water in the northern Gulf. The amplified, weird pattern over the West and Plains, responsible for our cold front, the ice storm in Oklahoma and parts of Texas, and the snow in the Rockies helped supercharge Zeta as it approached Louisiana.

This was a case where shear was actually in a sweet spot for a storm and helped it along. The deep trough and very strong jet stream winds over Texas (known as a jet streak) actually helped Zeta find an environment that would be hospitable for a low pressure system to intensify within. This further underscores that water temperatures are far from everything when it comes to hurricane intensity. In this case we had a Gulf of Mexico that was only slightly supportive for a storm, but the storm got juiced by the atmospheric pattern over the Plains and Southeast. And the end result was a memorable, odd late season storm. Zeta also will end up being the strongest storm to make landfall so late in the season on the entire Gulf Coast. Zeta’s forward speed of over 45 mph over the Southeast made it one of the fastest moving storms on record (for any date) over the continental United States.

And we aren’t finished. The National Hurricane Center has 80 percent odds that a tropical wave in the Caribbean (dubbed Invest 96L) will develop into a depression or storm in the next 5 days.

A tropical wave tagged as Invest 96L has an 80% chance of development over the next 5 days. (NOAA)

If it gets a name, it will be called Eta, and 2020 would officially tie 2005 for the most storms on record in the Atlantic basin. As much as it pains me to write this, Eta is a storm that should probably be watched from Louisiana to Florida. It’s likely to percolate off the coast of Central America much of next week before perhaps being ushered north next weekend by our next weather maker over the Plains & Texas. How exactly that plays out is TBD. This is highly unlikely to come to Texas, but there a number of model solutions that bring it into the eastern Gulf or off the Florida coast. So, yet again, another one for our neighbors to the east to watch. We’ll update you on Monday.

A series of cold fronts will toy with Houston over the next week

Over the next week or so, southeast Texas is going to be visited or perhaps taunted by several cold fronts. We still have questions regarding the exact timing of most of them, but we can continue to point to some windows of when they’re most likely. Our first one arrives later today. Let’s break it down.

Today

Our first cold front is still off to the north, steadily heading this way. That won’t arrive until later, and ahead of it, look for a few showers or perhaps a thunderstorm through the day. Many places will probably stay dry, but in general, the odds of storms may increase a bit late this afternoon. More of the same temperature-wise, with 80s and fairly uncomfortable humidity.

The front should arrive in the northwest suburbs late this afternoon and in the immediate Houston area after 4-5 PM or so. Behind the front we’ll see temperatures drop off 5 or 10 degrees, and you’ll notice a fairly brisk breeze out of the north.

Weekend

Saturday morning will start off much cooler than we’ve had in recent days. Many places will start in the 50s, with 60s south and east of Houston.

For those looking for a more autumn feel, Saturday morning will provide low temperatures that fit the script a bit better. (NOAA forecast via Weather Bell)

Expect a good deal of cloud cover tomorrow morning. We should see increasing sunshine in the afternoon. High temperatures will top off in the mid-70s in most places. If clouds are a bit more stubborn, we may not get out of the upper-60s, however.

Onshore flow resumes later Saturday, and the humidity will slowly inch back up into Sunday. Morning lows on Sunday will be in the 60s in most places. With a mix of clouds and sun, we’ll probably make it to 80 degrees or a couple degrees warmer on Sunday afternoon. We’ll mention that a passing shower cannot be entirely ruled out Sunday, though it’s likely to be dry in most places.

Next week

Things turn very, very messy from a confidence in details perspective on Monday and Tuesday. Another cold front pushes into the Houston area, but it appears that this one is going to stall out right over the city, almost perfectly over US-59/I-69. This means clouds, perhaps some sun, and at least a chance of showers and storms. Temperatures later Monday and Tuesday may be rather variable across the area with the east side perhaps 10 to 15 degrees warmer than the west side of the region with high humidity south and east and lower humidity north and west. This can be seen when you look at forecast dewpoints from the European model.

Forecast dewpoints from the European model show the front, the boundary between more humid and less humid air straddling the Houston area from late Monday into early Wednesday. (Pivotal Weather)

Notice how the boundary between the more humid air (in purple and dark turquoise) and less humid air (in green) basically straddles Houston for most of Tuesday before shifting back west (meaning everyone warms up a bit) on Wednesday. Basically, this is a front that taunts us mostly.

After it pushes back west on Wednesday, look for a warm day. The front should finally get a shove through the entire area by Thursday or Friday. I don’t want to commit to a day just yet because modeling has handled fronts in the days 5 to 8 range quite poorly this autumn. But we still believe we’ll get a clean cold front passage late next week, hopefully setting up a nice daylight saving time weekend. More on that Monday!

In case you missed it, today is our fifth anniversary at Space City Weather! It’s a privilege to be part of this, and thanks to Eric for keeping me around these last five years. We have some fun things planned down the line, and as always we’ll be here when you need us.

Houston weather returns to autumn — for now

Good morning. We’ve had quite the array of rainfall totals across the region since yesterday evening.

Rain totals have ranged from nothing at all to almost 2 inches in parts of the area, with Spring, The Woodlands, the Northside, and EaDo seeing the highest totals. (Harris County Flood Control)

Areas near Spring and The Woodlands saw north of an inch and a half of rain, while parts of Galveston and Brazoria Counties saw virtually no rain at all. East Bernard (not shown) in Wharton County also likely received close to 2 inches of rainfall.

Today

The front is through, and showers continue in its wake. These showers may be a bit stubborn to end. Areas north and west of Houston will likely see brightening skies this afternoon. But showers could persist off and on elsewhere. We’ll struggle a bit in the temperature department today, with cloud cover dictating how warm we get. Those that see sunshine could push 70 degrees, while those under clouds and showers through early afternoon may not get much above the low-60s. Northeast winds will be noticeable, giving today a distinct autumn feel as they gust to 20 mph or so in Houston and as high as 35 mph near the bays and Gulf.

Weekend

Overall, if you have weekend plans, you’ll be fine in most cases. There’s a little nuance to touch on though.

Saturday will be a bit of a toss-up day. The morning should be beautiful, cool and crisp, with temperatures generally in the 50s inland and 60s at the coast.

Morning lows in the 50s inland and 60s at the coast and south will be the rule for Saturday morning. (NOAA forecast via Weather Bell)

But we will see some cloud cover around, especially extending from southwest to northeast through the day. A little sporadic light rain or drizzle will be possible, mainly southwest of Houston. High temperatures should find their way into the upper-70s in most spots, perhaps 80 degrees or so with enough sunshine. Winds should be a more reasonable 5 to 15 mph.

On Sunday, the morning won’t be nearly as cool, with lows in the 70s at the coast and mid- to upper-60s inland. Onshore flow resumes, and you’ll notice building humidity by Sunday morning. We should see a mix of sun and clouds, and an isolated shower can’t be entirely ruled out. Looks for highs back firmly into the 80s in most spots.

Early next week

Monday should be a similar day to Sunday with warm temperatures, high humidity, and at least a chance for a passing shower or storm. Tuesday likely carries slightly better chances for scattered showers or thunderstorms. More of the same follows Wednesday. It’s a bit tough to pin down which days and times will have the highest rain chances, as we’re dealing with some fast moving disturbances that are difficult to time out this far in advance. But in general, early next week is clouds & sun, a chance for thunderstorms, and highs in the 80s, lows mostly in the 70s. Our next front is unlikely before next weekend.

Tropics

Eric’s touched on the tropics a bit this week. The bottom line is that we have nothing at all to worry about here.

The potential for a couple more tropical systems exists next week, but none will be an issue in the western Gulf. (NOAA NHC)

The Caribbean system may develop, but it would track due north and eventually northeast, away from the Gulf and probably away from the U.S. Another system seems likely to develop in the open waters of the Atlantic. The next two names on the list are Epsilon and Zeta.

Hurricane Delta heads for Louisiana, and then the heat returns to Houston

6:20 am CT Friday: Hurricane Delta has completed its north turn and is now steaming toward the Louisiana coast. Delta is a large storm in size, and as a result, we are seeing some rain here in the Houston area, especially on the east side. But Delta will exit quickly tonight, setting the stage for a sunny weekend but also the return of heat.

Hurricane Delta Update

As of the 4 am CT advisory, Hurricane Delta still had 120 mph maximum sustained winds, supported by observations from aircraft investigating the storm. Since that advisory, little has changed for the most part, but Delta is now moving into an area of high shear and cooler water temperatures.

Hurricane Delta is moving into a much more hostile environment for a hurricane, with substantial wind shear (indicated by the red contours on this map), cooler water temperatures, and likely some dry air as well. (University of Wisconsin CIMSS/SSEC)

In addition, the southern side of the storm is beginning to feel the effects of drier air being swept off Texas and Mexico in the wake of its passage. The GFS model image below is valid for Noon today and shows drier air (brown) getting dragged into the southern half of the storm. Delta is likely to come ashore fairly lopsided, with a potent northern half and a much more frazzled and weaker southern half.

Dry air will also help to begin to weaken Delta as it wraps into the southern half of the storm through the day today. (Tropical Tidbits)

So this storm has likely peaked in intensity over the Gulf and will slowly weaken up to landfall. That said, it remains a dangerous storm, as the large size of it will allow for a storm surge in Louisiana that is more significant than the storm’s landfall intensity will probably suggest. In addition, the expansive tropical storm force wind field (which now has a radius of 160 miles north and east of the center) will allow for damaging winds in weakened, vulnerable parts of Louisiana. So for southwest Louisiana, this remains a serious storm.

Local impacts from Delta

We have already begun to see tides increase on the Upper Texas coast. San Luis Pass is just on the cusp of minor flooding this morning.

San Luis Pass is just on the edge of minor flooding as of this morning’s high tide. (NOAA)

We are now past high tide, so this will likely level off now or perhaps rise just a little more. A similar story is playing out in Galveston. Tidal levels on our slice of the Texas coast will probably be similar to what we saw with Hanna and Laura and lower than what was experienced with Beta. Watch for the risk of some minor flooding from the Galveston Bay side in Bolivar and Galveston itself later today with winds shifting behind Delta.

Rain continues to circulate in from the east, and most of the eastern half of the Houston metro has seen about a quarter-inch so far.

Rain will continue to pivot through the area during the course of the day. No flooding is expected in the Houston area. (College of DuPage)

Total rainfall in the Houston area should be under an inch for most folks, and no flooding is expected in our area. Look for upwards of 2 to 4 inches in the Golden Triangle, with minimal flooding issues expected and 6 to 8 inches in Lake Charles, where street flooding could be a bit more serious of a problem.

Winds at Galveston are gusting just a bit under tropical storm force this morning (35 mph as of 6 AM). We could see sustained winds or gusts to tropical storm force (45 mph or so) along the immediate Gulf coast. In Houston, wind gusts will be unlikely to get much past 25 or 30 mph, and no serious issues are expected due to wind for the vast majority of the region. Winds in the Beaumont area could gust to 40 to 50 mph, with slightly higher winds closer to the coast. In Lake Charles,  winds could gust as high as 50 to 70 mph for a time later today, with hurricane conditions on the immediate coast of southwest Louisiana, in addition to a significant storm surge on the immediate Gulf coast there.

Eric and I continue to send our thoughts and best wishes to our neighbors in the east. Even a best case scenario outcome with Delta is still a pretty bad day for southwest Louisiana, and they will continue to need our help in recovery.

After Delta: Weekend

With Delta moving off to the north tonight and tomorrow, the Houston area is going to clear out quickly in its wake. Saturday should be a lovely day, albeit a bit warm. Expect sunshine with highs in the upper-80s. Humidity should be tolerable. More sunshine will follow Sunday, but temperatures are going to crank up and so will the humidity. Sunday is going to feel like a summer day, with highs in the low to mid-90s.

Sunday will feel like early September, with highs in the low to mid-90s and fairly uncomfortable humidity. (NWS forecast via Weather Bell)

For the holiday on Monday, expect more of the same, with at least low-90s and sunshine.

Tuesday & beyond

A cold front is likely to press into the area later on Monday, but how far south it gets is an open question. While a few showers will be possible, we expect this wash out over us, which should lead to a slight cooldown in temperatures and slightly lower humidity. By the end of the week, we may see a more robust cold front enter the picture, driving in more pleasant weather for next weekend, but even that is not a guarantee at this point. More on this for you on Monday.

Our next update on Delta will be posted by 2:30 pm CT today.