Matt Lanza

Explaining a furiously stormy June and last week’s wild wind and hail in Houston

Hello on a Sunday, not because the forecast has changed (it’s going to be extremely hot the next 5 to 6 days, with excessive heat warnings in place again), but because I think folks deserve an explanation about this month. Our forecasts have not necessarily been horrible or anything, but we have all been caught by surprise at the ferocity of some of the storms in June. Many of you have lost power at one point or another, some for days, while others have sustained property damage from winds or hail. So, why?

The National Weather Service forecast office in Houston has issued 47 severe thunderstorm warnings this month across the region. There have been a total of 159 wind or hail reports from across the region.

A map showing all of the warnings and storm reports from the National Weather Service Houston office for the month of June in the Houston area. (Iowa State Mesonet, IEM)

The actual number of damage reports is certainly much higher, as some were surely consolidated or others were not submitted to the NWS office. Whatever the case, it’s been a lot. The only portions of our area mostly spared some element of significant severe weather have been in Fort Bend and Wharton Counties through Lake Jackson and Matagorda Bay.

Let’s quickly recap a few of these events.

June 4th

We were delivered an early wake up call back on June 4th, when storms rolled through the metro area between Midnight and 2 AM or so.

Thunderstorms oozed through Houston early on Sunday morning, June 4th with wind gusts as strong as 60 to 70 mph. (RadarScope)

Bush Airport reported a 62 mph wind gusts with these storms, and there were numerous reports of trees and powerlines down. These storms were not expected to hit so hard or quite so soon, so this one caught us a little off-guard. The 3rd was a relatively pleasant day with comfortable dewpoints and highs in the mid-90s (which sounds wonderful given where we are today). But with a weak upper low over Texas, that’s all we really needed to generate storms, and they just managed to survive the trip. Upper lows are notoriously fickle, and as such, we got burned.

June 8th

Wind and hail ripped across the area on the evening of June 8th. This event was better telegraphed than some others this month. We mentioned a good chance for storms and underscored the uncertainty around the storm evolution. So this one didn’t catch us off-guard. But it still ended up pretty vigorous.

Wind damage near Cy Creek High School from June 8th storms (@addicted_to_reeses on Instagram)

Both IAH and Hobby gusted to around 45 mph with these storms, while just off of Texas City recorded a 67 mph gust. Centerpoint had something in the vicinity of 175,000 outages I believe. Hail reports were several, and rain totals of 2 to 3 inches southeast of Downtown Houston produced flash flooding.

June 10th

The storms on Saturday the 10th were also somewhat well telegraphed, as we were outlooked for severe weather and we noted the chance in our posts. The City of Houston was mostly fine in this one, but areas north and east and well northwest of the metro area saw some significant storm reports. Bush officially gusted to 58 mph, while Hobby hit 53 mph. Multiple 60 mph wind gusts occurred in the bays and off Galveston, while hail of golf ball size was reported in Burleson County.

June 21st

This past Wednesday’s storms were utterly ferocious.

Bush Airport’s 97 mph gust toppled Hurricane Ike from the top of the leaderboard there, with numerous other locations seeing 50 to 80 mph wind gusts, knocking out power to hundreds of thousands, some of whom remain in the dark as of this morning.

These storms were poorly forecast. We did talk up rain chances for Thursday, but in reality these came roaring in a good 12 hours faster than anticipated on Wednesday evening, and obviously with more rage than we predicted too. We can look to Friday for further evidence of this as well.

June 23rd

The latest round of violent storms struck on Friday evening with hail and wind. Hail to the size of golf balls and hen eggs fell south and east of downtown Houston and on the west side of the city in two pretty distinct belts.

Hail — and then the gust front from Lindale Park on Friday evening (@tokala on Instagram)
Some violent hail from some of these videos and also some strong wind too. We got a lot of reports from the Second and Fifth Wards, the East End, and Lindale Park. Hail reports continued into Downtown and just west into Montrose and the Heights but the hail became less frequent and smaller in size. Additional hail sprung back up as the storm moved west across the city, with large hail reported near SH-6 and north of I-10, from near Bear Creek and Copperfield into Jersey Village.
These storms also knocked out power to a bunch of additional folks, though wind was not the big issue here in most cases.

What happened this past week?

So, what exactly was at play this week, and why did we miss the mark on the forecast?

Often times in summer, high pressure tends to “anchor” in one part of the country or another. This month, we’ve seen it anchor mostly over South Texas and Mexico.

High pressure has been mostly anchored over Mexico and South Texas, while thunderstorms have been most active on the periphery from Colorado into the Southern Plains and into the Southeast. (NOAA)

Storms have generally driven the periphery of the ridge, which has led to high precipitation over the last couple weeks from Colorado into the southern Plains and Southeast.

Rain totals over the last couple weeks have been at their highest from Colorado into Oklahoma, northeast Texas and into the Southeast. (NOAA)

There were a couple changes this past week. The high reoriented closer to Big Bend (which allowed some all-time record temps to fall in South Texas), but it also shifted our flow to more northwesterly or northerly.

The upper level weather map from Wednesday afternoon showed high pressure over northern Mexico, allowing for northwest flow to slide disturbances into SE Texas. (Tropical Tidbits)

Why is this important? A couple reasons. Being along the periphery of the high allows for the best combination of daytime heating and instability, as well as being “in the way” of quick moving disturbances. The amount of instability that developed on Wednesday afternoon in particular was extremely high, some of the highest we usually get around here. We just needed a spark, and we got it. We thought the disturbance was targeting more like late Wednesday night or Thursday morning, which would have resulted in storms but perhaps not high-end severe storms. Instead, it coincided with peak instability on Wednesday evening, and alas we got walloped.

On Friday, we expected some storms to the east. That happened in the morning and afternoon. But with lingering boundaries and a little spark from a nearby upper disturbance, we were able to just keep building storms again and again as they migrated around the periphery of the developing high pressure over Texas — until it just ran into dry air and fizzled southeast of College Station.

So Wednesday’s storms were more driven by a strong disturbance coinciding with peak heating. Friday’s storms were more mesoscale in nature (smaller scale things like wind boundaries helped buoy them). Both events were enhanced by extreme levels of instability provided by heat and humidity. Wednesday’s storms brought significant wind because they were 60,000 feet in height and collapsed, bringing all the wind down with them. Friday’s storms brought more hail issues than wind issues because the storms were 60,000 feet in height and continually redeveloping. Updraft after updraft allowed for large hail to form. Different drivers and different reasons for the outcomes we experienced.

In general, predicting these types of storms is kind of a roll of the dice. Disturbances “ride the ridge” at different speeds, which are occasionally out of sync with your forecast. And localized effects can lead to more substantial outcomes. Unfortunately on Wednesday, the storm began collapsing just as it approached the densely populated northern half of the metro area. And on Friday, the storms peaked in height & intensity right over the city. We still struggle at times with these types of events, but we learn from them to hopefully help next time.

Hopefully this is a useful explanation! We’ll be back with you as normal Monday morning.

Relentless Texas heat continues and will worsen again next week

Through June 10th, Houston had experienced our coolest June since 2017, with a chance to perhaps outpace that year too. Since June 10th and through yesterday, it has been the third hottest mid-June stretch on record. When all is said and done, this will end up being one of our hottest Junes on record. We are firmly in it over the next week.

Today

I am not prepared to say that our rain chances are over with just yet. There are storms offshore of Louisiana this morning, along with a couple clusters of storms riding the periphery of the heat ridge over Texas.

Storm clusters riding the periphery of the heat ridge over Texas may lead to some showers and storms, mainly east of I-45 today. (College of DuPage)

As those clusters drop south and east, complex interactions with lingering boundaries from storms in recent days could yield at least a few new storms, mainly east of I-45. I think that’s the exception, not the rule and that the intensity of the storms will (hopefully) be much less than seen the other night. So don’t bank on storms. But just know there’s a chance.

Outside of that, more of the same: Clouds, sun, a heat advisory that could be upgraded to an excessive heat warning, and plentiful humidity. Highs will be in the upper-90s.

Saturday & Sunday

Hot. Highs near 100, lows near 80. Rain chances decline to near zero.

No relief is expected through next Thursday. (Weather Bell)

Next week

We will escalate the heat daily until about Wednesday or Thursday, when things should peak. This will push us into the low-100s for highs, with lows again near 80. While humidity doesn’t look *as* high as this past week’s heat, it will likely be high enough, along with slightly less wind to lead to another round of potential Excessive Heat Warnings.

Wet bulb globe temperature is another measurement of heat stress on the body that we can use to assess the seriousness of a heat wave. In this case, it will be at “extreme” levels this weekend and next week (Weather Bell)

When we look at the wet bulb globe temperature forecast for Houston we see extreme values continuing, much like this past week. Heat index basically factors in humidity and temperature to give us a “feels like” value in the shade. Wet bulb globe (WBGT) factors in things like latitude and date to generate sun angle, wind speed, and cloud cover, in addition to temperature and humidity to generate a measurement of heat stress in the sun. What I like about WBGT is that it’s sort of a universal measurement. Once above 90, that poses extreme stress on your body, whether in Houston, Miami, or Phoenix. Houston would typically be in the moderate to high level of WBGT this time of year, so the fact that we’re in “extreme” levels speaks to how abnormally hot this is for us.

A long way of saying: Take it easy on yourself. Go slow. Drink water. Maximum heat precautions need to be fully implemented over the next week.

Hopefully the “death ridge” responsible for this heat shifts into the Desert Southwest next weekend or the week of July 3rd. Should that happen, perhaps we can resume more typical summer weather here in Houston, which while still certainly hot, would be a little less stressful on our bodies.

City of Houston under an excessive heat warning for the first time in 7 years

We’ve seen a lot of comments from folks on the site and social media along the lines of, “Well, it always gets this hot in summer and always has and this is no different so why are you making a big deal of this?” It is true: Houston is hot in summer. From May through September, you can describe Houston as hot, humid, sultry, or whatever other colorful adjective you want to use. Some may say, the difference between 94 and 98 and 100 is difficult to perceive anyway, so what difference does it make?

An excessive heat warning has been issued for Houston for the first time since August of 2016. It covers the entire region away from the coast. (NWS Houston)

Usually about twice per summer or so, the heat in Houston goes to what I call the next level, where it’s hot like always, but it just feels worse. This is the type of heat where your body can truly suffer if you don’t take it seriously. We’re in one of those periods right now, arguably one of the worst such periods in several summers. Heat index values yesterday were all over the place, including near 115° in spots around Houston and even near 120° in spots near Corpus Christi and Port Arthur. A more typical summer day may feel along the lines of 99 to 105° or so. So this has moved into the higher echelon of next level of heat. Hence, we are trying to convey that this is more serious than normal summer heat. And it will continue for awhile longer. Please take it seriously this holiday weekend, especially if you’ll be attending any of the Juneteenth celebrations in the area or outdoors in any capacity.

We don’t want to be too preachy, but this is more serious heat than is typical for Houston. (NWS Houston)

We have energy saving tips from our sponsor and partner Reliant just below the forecast. As the heat puts stress on the grid over the next several days, these energy saving tips will come in handy.

Friday & Saturday

All we can tell you about these two days is that they’re going to be miserably hot and humid. Expect heat index values of 110° to 115° or higher, with actual temperatures near 100° inland and in the 90s along the coast. A heat advisory is posted for the coast, while the rest of the region has an excessive heat warning. The last time the city of Houston had an excessive heat warning was in August of 2016. So, again, this speaks to both the rarity of heat of this magnitude, as well as the fact that it’s June not August.

Heat index values may peak over 115° in spots today and tomorrow, meaning maximum heat safety precautions should be taken. (NWS Houston)

Let’s not forget about nighttime. Low temperatures will struggle to get much below 80 degrees each night. This sort of compounding heat can take a toll, especially on the very young and elderly. If you’re headed to the Gulf for some relief, please also keep in mind that rip currents look a bit strong this weekend, so be aware of that if you jump in the water.

Sunday & Monday

Copy and paste Friday and Saturday’s forecast and tweak the temps by 1 or 2 degrees in either direction. More heat warnings and/or advisories are a guarantee.

Rest of next week

By later next week there’s some chance that we may exit this “max heat” type situation and get back to something just regular “abnormally hot.” So instead of heat index values of 110 to 115°, maybe we fall back to more like 105 to 110° or so. It’s a maybe, but at this point, we’ll take whatever good news we can get.

In terms of rain chances, they remain near zero until perhaps midweek or late week next week, when maybe we can bump them up to 10 or 20 percent on a good day.

A Message From Our Sponsor, Reliant

As Eric and Matt have warned us, the summer heat is here. With triple-digit temperatures forecasted for the coming week, Reliant is sharing helpful tips to stay cool while managing your energy usage.

  • Setting your thermostat four degrees higher when you’re away from home for more than four hours can help reduce electricity usage.
  • Raising the temperature of your home by even a few degrees also reduces energy consumption. Every degree of cooling below 78 degrees increases your energy use by 6-8%. While the suggested temperature for ideal energy use in the summer is 78, a comfortable temperature setting is a personal preference – just know every degree makes a difference.
  • Rotate your ceiling fan counterclockwise for a wind chill effect. This can make the temperature in a room feel up to four degrees cooler, allowing you to be more comfortable and adjust your thermostat to save money. Don’t forget to turn off your fan when leaving the room.
  • Use blinds or curtains to reduce solar heat gain by up to 50 percent. Direct sunlight can increase the demand on your A/C by as much as 30 percent.
  • Check air filters monthly and replace as necessary. A clean air filter can keep your A/C running at peak condition.
  • Avoid using heat-producing appliances like the clothes dryer, dishwasher, or oven during the hottest times of day. These appliances can cause your A/C to work harder to keep your home cool.

Find additional energy efficiency tips from Reliant by clicking here.

Heat will continue to build through the week in Houston

On Monday, Houston topped off around 95°, after a 94° on Sunday and 93° on Saturday. So far at least, our temperatures seem to be underachieving a bit. That may be a bit of cloud cover or the relatively wet weather we had through late spring acting against heat. Regardless, it will remain plenty hot through the week.

Today

Today’s upper air temperatures are expected to be about 1 to 2°C warmer than they were yesterday, which should translate to a bump of a couple degrees to our high temperatures. Look for mid to perhaps some upper-90s in most inland spots, slightly cooler at the coast. Storms are expected to remain well north of the area today, but some clouds from those storms could filter into some of the region.

Heat advisories are now posted southwest of Fort Bend County and could be expanded depending on how things evolve today. (NWS Houston)

Peak heat index values (or feels like temperatures, if you prefer) will be in the 103 to 107° range in Houston, just shy of heat index criteria in most of the area. But to the west, they are expected to flirt with 108°+, requiring a heat advisory. This could be expanded later today and certainly will be as the week goes on.

Wednesday

Morning lows will be in the upper-70s tomorrow. We tack on another 1-2 degrees on Wednesday in the upper atmosphere, so look for mostly upper-90s for highs here. As seems to be the case, some passing storms well off to our north may send some “debris” clouds this way which may keep the risk skewed slightly lower for high temps. We’ll see.

Heat index values should ratchet up a little bit tomorrow as temperatures increase a bit too. (Pivotal Weather)

Heat index values will nudge up some tomorrow, with peak readings perhaps more into the 105 to 110° range, which could yield wider coverage of the heat advisory.

Thursday through Sunday

No changes to the forecast here with minimal rain chances (model probabilities are under 15 percent all days) and a mix of sun and clouds each day. High temperatures will likely be in the upper-90s most days with at least a chance at 100+ officially. But admittedly, after yesterday I am not as convinced we do that. But, whether it’s 100+ or not, we will likely see heat index values average in the 105 to 110° range on all days, meaning we will potentially put together a string of heat advisory days, so make sure you’re keeping cool and drinking plenty of water.

We still cannot confidently answer when this heat will start to relax. Maybe later next week.

Tropics

We continue to update the tropics daily over at The Eyewall, and we have little to discuss right now! Good news for sure, and with this dry, hot air mass dominating Texas and the western Gulf, we’re very much in the clear for the next 7 to 10 days. Look for a larger feature at The Eyewall tomorrow that goes in depth on what has been happening in the Gulf of Mexico in recent years.