South Texas Arctic Outbreak February 2021
Low temperatures from 1895 broken as a winter storm shuts down Texas. Let's talk about what happened & the impacts felt around the region.
Winter Storm Overview
Following unseasonably warm temperatures in the 70s and 80s across much of South Texas in early February, a surge of Arctic air invaded the region on February 11th. This was followed by even colder air on the 14th, complete with a mix of wintry precipitation (seen to the right). Winter Storm Warnings were issued all across the state as the threat of winter weather increased.
Winter Storm Warning from Feb 14th
Winter Storm Warnings covering the entire state of Texas
In addition to the Winter Storm Warnings, Freeze and Wind Chill Warnings were also in place as temperatures plummeted and wind chills dropped to near 0º.
Freeze and Wind Chill Warnings from Feb 15th
Anywhere from a trace of snow and ice to as much as 1/4 inch of ice and one inch of snow fell across the region late in the night on the 14th and resulted in many road closures.
Snow and sleet accumulations from Feb 14-15th
Ice accumulations from Feb 14-15th
In an effort to gather more data to help us better time the transition to a potential snow mixture along the Coastal Bend, we launched a special 06Z weather balloon into the storm. At the time of the launch, it was 25º with winds gusting to 35 MPH and a wind chill of 7º
06Z KCRP soundings
The image above is the result of that weather balloon launch. The solid blue line indicates the freezing line (32ºF). You can see most of the atmospheric profile is below freezing (to the left of the blue line) except for the area inside the red box. With little moisture in the mid-levels of the atmosphere, little snow was produced, and explains why most of South Texas saw mainly freezing rain mixed with some sleet.
00Z Del Rio Sounding
Farther north, snow was able to develop within a deeper moist layer aloft.
Additional bouts of light freezing drizzle redeveloped during the evening and overnight hours from the 16th (seen to the right) through the afternoon of the 18th (shown below), with some light snow even falling over the northern Brush Country at times. Additional Winter Weather Advisories and Winter Storm Warnings were needed through the middle of the work week.
Advisories and warnings from Feb 16th through Feb 17th.
Advisories and warnings on Feb 18th.
Radar on Feb 18th.
However, the most impactful weather was the protracted period of freezing temperatures with historically cold readings at times - some that shattered records as old as the 1895. This brutal cold contributed to widespread power outages and water shortages over much of the Lone Star State.
Records Were Shattered!
The 2021 Cold Air Outbreak across Texas broke a plethora of records across South Texas, some dating as far back as 1895! This event was a total of two systems, one which initially ushered in the arctic air and a second that re-enforced it.
Max and Min temperatures from Feb 12th-Feb 18th
In total, eighteen records were broken:
- Records Lows: 11
- Low Maximums: 7 (coldest high temperature recorded for that day)
Coldest temperatures across South Texas from Feb 14-17th
Despite all the records and the prolonged period of time below freezing, the coldest temperature ever recorded for those sites were not met and live to see another day. The coldest temperatures ever recorded for Corpus Christi remains 11°F dating back to 1899, 9°F dating back to 1989 and 1930 for Victoria and 11°F for Laredo dating back to 1983.
The graphic below shows just how much colder than normal we were during this cold snap. Temperatures were well below normal for the middle of February!
Hopefully it will be a long time before we see these temperatures across South Texas again.
South Texas Impacts
The winter storm resulted in devastating impacts across South Texas. We began seeing impacts during the late afternoon to early evening hours on Sunday, February 14th as freezing rain began to accumulate on area roads. Road closures all across the region quickly followed the onset of icy conditions.
Arctic temperatures and ice accumulation immediately took a toll on the power grid. The majority of South Texas lost power during the early morning hours of February 15th. Many residents endured multiple nights of temperatures below freezing without heat.
As we slowly warmed back up and stress on the power grid was relieved, power was gradually restored to the region.
In addition to the widespread power outages, residents were faced with another hurdle: a Boil Water Notice.
Freezing temperatures resulted in frozen pipes which, unfortunately, led to pipe bursts. Cities and counties all across the region were placed under boil water notices as local officials worked to resolve the issues and guarantee the water supply was safe for consumption.
Sea Turtle Cold Stunning
This surge of arctic air was especially rough on our local sea turtle population. When temperatures plummet, the water temperature also falls. The image below shows the water temperature in the Laguna Madre dropping from just over 70º around Feb 11th and dropping to less than 40º on the 15th.
Laguna Madre temperatures courtesy of Philippe Tissot
Sea turtles are cold-blooded and rely on the heat of the environment to keep them warm. When the temperatures fall like they did, the turtles are no longer able to stay warm. As a result, the become lethargic and unable to swim. According to the Texas State Aquarium, "Many of the sea turtles may have pneumonia, and some could have other medical conditions or injuries from being washed against rocks. Cold stunned turtles require expert medical care."
Rangers holding and transporting sea turtles. NPS Photos.
"We anticipated this will be the most significant cold stunning event to date and prepared accordingly." - Jesse Gilbert, TSA’s Senior Vice President and Chief Operating Officer
Sea Turtle Science and Recover employee and volunteer scan cold stunned turtles for identifying tags. - Padre Island National Seashore
A number of organizations across the Coastal Bend work together to rescue and rehabilitate these sea turtles before releasing them back into the wild.
Links to learn more about this:
Thank you to everyone who submitted their photos from the storm to us on both Twitter and Facebook. We received hundreds of photos from across the region. Unfortunately we could not post all of them on this page, but you can still view them by clicking the two links below. Thanks again! - NWS Corpus Christi
Various photos from across the Coastal Bend
Various photos from across the Coastal Plains
Various photos from across the Victoria Crossroads
Various photos from across the Brush Country
Miscellaneous photos from across South Texas
