Houston to see mostly manageable rains today and Wednesday before a weekend warmup

In brief: In today’s update we take a look at increasing shower activity today and Wednesday before our rains mostly dry up. That will leave us with a more humid and increasingly warm air mass heading into the weekend. We also take a look at winds this weekend for our friends participating in the MS 150 ride.

Before sunrise on Tuesday rains are (mostly) behaving across the Houston region. (RadarScope)

Drier air mass is gone

After Houston saw widespread showers on Saturday a drier air mass moved in to the region on Sunday. By Monday enough drier air was holding on such that even though a disturbance moved in from the west was producing precipitation in the atmosphere, much of this was drying out before it reached the ground. The lower atmosphere is more saturated now, so those showers are breaking through.

Since midnight much of the region has received between 0.25 and 0.5 inch of precipitation, and we are likely to see ongoing rain chances today and Wednesday. The good news is that, for the most part, I expect these showers to be mostly behaved. That means that while heavy rain and street flooding are always possible, in this case I expect showers to largely be of the light-to-moderate level.

Tuesday and Wednesday

As mentioned above, we’ll see on-again, off-again showers for much of today and Wednesday. High temperatures today will likely top out in the lower 70s, but Wednesday could be a little warmer if we start to see some partially clearly skies later in the day. The rain chances should start to ebb by Wednesday afternoon or evening. By then we’ll just be left with fairly muggy air and warm nights with lows around 70 degrees.

Thursday and Friday

These will be a pair of partly sunny days with temperatures in the 80s. Thursday may be a shade cooler than Friday, but both days will see plenty of humidity and some background rain chances on the order of 20 percent. Afternoon winds will gust up to about 20 mph from the south, with lighter conditions at other times. Nights remain in the lower 70s.

Saturday and Sunday

A warming trend continues into the weekend, with highs likely in the upper 80s, and partly to mostly cloudy skies. With dewpoints in the vicinity of 70 degrees it will feel plenty humid. As for rain chances, they’re not zero, but they’re pretty low, and anything that falls should be light.

Forecast for sustained winds at 1 pm on Sunday. Wind gusts will be about twice as high. (Weather Bell)

So what about winds? If you’re participating in the MS 150 ride this weekend that’s what really matters. The route on Saturday is generally westerly, and then it turns more northerly on Sunday. Winds at dawn on Saturday will be mostly southerly, at about 5 mph, so a cross wind. They’ll be stronger by the middle of the day, 10 mph with gusts up to 20 mph. The story will be similar on Sunday, so more of a pure tail wind that day. You should be flying that day!

Next week

Warm temperatures, with highs near 90 degrees, will continue into next week. Some sort of front may work its way into Houston by Tuesday or Wednesday, but your humble forecaster is making no concrete predictions on that score. We’ll have to see what happens.

After Saturday’s downpours, more rain is on the way for Houston

In brief: Following widespread showers this past weekend, the region will see ongoing rain chances through the middle of this week. We’ll see a warming trend heading into the weekend, which looks to be fairly humid.

Rain accumulation forecast for Saturday and Saturday night. (NOAA)

Saturday rewind

Much of the Houston area received a good soaking on Saturday as a cold front slowly moved into the region. Some areas got a little too much rain, with some street flooding occurring from just southeast of downtown out Highway 90 and Interstate 10 toward Sheldon. Some of these locations received 3 to 5 inches, whereas most of the region picked up 0.5 to 2 inches. Although it came on the weekend, much of this rain was welcome after a dry winter and start to spring. Our overall pattern will now remain fairly wet this week as a moist airmass remains in place.

Monday

Temperatures are generally in the low 60s this morning, with winds shifting to come from the east. Skies are also mostly cloudy and that’s not going to change much over the next several days. It’s possible that we see some sprinkles today, but there’s enough dry air about that any showers may not make it to the ground. In any case, if there is light rain today it most likely will occur to the west of Interstate 45. Otherwise expect a high around 70 degrees, with modest easterly winds. Lows tonight will drop into the lower 60s, and as the dry air edges out of the area our rain chances will go up overnight.

Tuesday and Wednesday

Increasing moisture paired with a disturbed atmosphere will lead to high rain chances on both Tuesday and Wednesday. Most of these showers look moderate in nature, but we certainly cannot rule out some heavier rainfall. I expect much of the area to pick up 1 to 2 inches of rainfall, but there will very likely be some higher isolated totals. I’m not ready to pull the trigger on a Stage 1 flood alert, but it is something that Matt and I will be watching given what happened on Saturday. Anyway, these should be days with highs in the 70s, mostly cloudy skies, and on- and off-showers. Rains should finally ebb on Wednesday evening.

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

Thursday and Friday

As rain chances diminish we’ll see a little more sunshine to end the work week, and this will allow high temperatures to rise into the low- to mid-80s for most locations. There will still be the odd chance of a shower, but for most of us probably not. Nights will be warm, generally in the lower 70s.

Saturday and Sunday

Skies remain mixed into the weekend, with warming temperatures and plenty of humidity. Expect highs in the mid- to upper-80s. I’ve had several questions about rainfall for this coming weekend. At this point my sense is that shower activity will be fairly limited. So clouds, yes. Rain showers? Probably pretty scattered, in the range of 20 percent each day. Lows remain in the lower 70s. If you’re riding the Texas MS 150 this weekend I’ll have a more detailed forecast for you tomorrow, but the good news is that winds should be from the south-southeast, so there will be a tail, or cross-tail wind most of the way.

Next week

At some point next week, in the Monday to Wednesday time frame, we might see another decent cool front. But the signal is not super strong in our modeling data, and this far out I’m skeptical of pretty much everything. Anyway, expect the week to start fairly warm and humid, and then we’ll see what happens after that.

Some parts of Houston may see heavy rainfall later today and tonight

In brief: Sorry to interrupt your weekend, but we wanted to update your expectations for rainfall later today and tonight. There are some indications that these showers may overperform a little bit, and that isolated locations in Houston may see 3 or more inches of rainfall.

Saturday Night Showers

Houston’s radar is quiet this morning, but beginning a little before noon we expect to see some showers and possibly thunderstorms fill in. Around noon, a few hours ahead of a frontal passage, we could see some showers develop along and south of Interstate 10 with plenty of moisture available in the atmosphere. These storms could be somewhat stationary, allowing for accumulations to build up over time.

Areas in great face a low, but non-zero risk of heavy rainfall later today and tonight. (NOAA)

Beginning later this afternoon a front will move down from the northwest, bringing more widespread showers and thunderstorms, and these are likely to persist, on and off, into the early hours of Sunday morning. At this time I don’t expect anything too severe, but thunderstorms (i.e. lightning) and moderate to heavy rainfall are possible.

Rainfall amounts will vary widely today, with most of the region likely getting in the vicinity of 0.5 to 2.0 inches of rain. However some locations, possibly near or southeast of downtown Houston, may well see higher totals of 3 inches or more. Again it is difficult to predict precise amounts or locations, but this could set up some street flooding conditions later this afternoon, evening, and during the overnight hours. These rains should move offshore early on Sunday morning, and by around sunrise for the coast.

NOAA rain accumulation forecast for later today and Saturday night. (Weather Bell)

In terms of temperatures, the region will remain in the vicinity of 80 degrees into the early afternoon, but should drop into the 70s by 3 to 6 pm CT, with continued cooling after that from the front. By Sunday morning much of the area could be as low as the lower 50s, which will feel rather chilly after the extended run of warmer than usual weather we’ve experienced. Sunday afternoon should feel pretty amazing outside with clearing skies, wind gusts dropping, and highs of around 70 degrees.

Cooler weather coming this weekend, and taking a closer look at the Ironman Texas forecast

In brief: In today’s post we dive into the weekend forecast, taking an especially close look at conditions for the Ironman event on Saturday in The Woodlands. Sunday turns cooler, with a couple days of spring-like temperatures before another warming trend.

Ironman Texas outlook

We’ve had a lot of questions about the weather for the Ironman triathlon in The Woodlands on Saturday, and here’s what I can tell you. Temperatures at sunrise will be about 70 degrees, rising to the low- to mid-80s during the afternoon hours. Dewpoints will be around 70 degrees through most or all of the daytime hours, so it will feel plenty humid outside. Skies should be mostly cloudy to completely cloudy. There will be a slight chance of light showers through the early afternoon.

Relative humidity at the start of the Ironman triathlon will be 90 percent, or higher. (Weather Bell)

Sometime around 4 to 8 pm a front will approach from the northwest, bringing noticeably less humid air and cooler temperatures. At any time beginning during the mid- to late afternoon, until the wee hours on Sunday morning, there will be a healthy chance of showers and possibly thunderstorms in the vicinity of The Woodlands. This is not guaranteed, but non-severe thunderstorms will be distinctly possibly on Saturday evening. For those who don’t know, a triathlon comprises a 2.4-mile swim, a 112-mile bicycle ride and a marathon. Good luck, everyone!

Thursday

With partly sunny skies our temperatures today are likely to be the warmest of the week, with much of the area away from the coast reaching the upper 80s. A few inland locations may even approach 90 degrees. Winds will be from the south at about 10 to 15 mph, with higher gusts during the afternoon. Lows tonight will only fall to around 70 degrees.

Friday

Another warm day, but with a few more clouds our high temperatures may top out in the mid- to upper-80s. It will still be very humid, with gusty southerly winds during the afternoon. Rain chances remain near zero.

Saturday

As noted in the Ironman section above, this will be another warm and humid day, but with cloudy skies likely limiting highs to the mid-80s. There may be a few, very light showers during the daytime. Shower chances pick up during the late afternoon, and especially Saturday night as a front moves through. I think most areas north of I-10 will see 0.5 to 1.5 inches of rain, with areas along and south of the freeway, closer to the coast, are more likely to get 0.25 to 0.75 inches of rain. Most of these rains are likely to come after sunset on Saturday and before sunrise on Sunday. At this time I do not expect any of these showers or thunderstorms to be severe. Lows on Saturday night should drop into the upper 50s for most locations away from the coast.

Lows on Sunday morning will be quite pleasant. (Weather Bell)

Sunday

This should be a partly to mostly cloudy day, with highs in the lower 70s. Some showers may linger near the coast on Sunday morning, but drier air will be steadily moving in from the north. Lows on Sunday night will drop into the mid- to upper-50s.

Next week

Monday will be another cool day, likely with highs in the low 70s. A chance of showers returns later on Monday with a passing disturbance, and this will persist into Tuesday. (If you’re headed to the Bruno Mars show on Tuesday, this is something to watch for. Speaking of which, it’s at RELIANT Stadium. Is anyone else happy with the reversion of the name?) With the resumption of the onshore flow on Monday we’ll see a warming trend back into the mid-80s next week.