The recent February 2021 cold weather disaster in Texas highlights the value of weather information and forecast alerts. But how cold did it get and how far was this from historical norms? Let’s take a look using a dashboard that can show us historically low temperature ranges.
Here are graphs that shows bands of normal, expected weather in major Texas cities based upon a 10 year statistical average. Notice how the recent daily temperature range (gray bars) dips far below the historically low range values in blue.
Dallas
Simply moving your mouse over the coldest date which appears to be 2/16/2021, we can see that the temp values for that date as well as the historical extremes:
Dallas got as low as 2.2 degrees F and lowest in the last 10years had previously been 19 degrees F. Typically it is between 40 and 60 degrees in Dallas.
If you want to run this query yourself you can use the direct query link to the Visual Crossing Dashboard:
https://www.visualcrossing.com/weather-history/Dallas%2CTX/us/2021-02-01/2021-02-19
Houston
https://www.visualcrossing.com/weather-history/Houston%2CTX/us/2021-02-01/2021-02-19
San Antonio
https://www.visualcrossing.com/weather-history/SanAntonio%2CTX/us/2021-02-01/2021-02-19
Was this the coldest storm in Texas?
So now that we know that this was the coldest storm in 10 years, one of the looming questions is whether this is the coldest ever in recent history? Should the power companies have anticipated or at least prepared for such an event as a possible emergency scenario? Let’s look. We have downloaded the raw data and requested data from as far back as 1980, we loaded this data (CSV format) into Excel and then sorted it by lowest temperature value for each of the cities.
For those of you who would like to acquire this data or similar for other locations, here is a tutorial for you to follow along with:
How can I download weather history data as a CSV file? – Visual Crossing Weather
Here are the top 10 coldest weather events we found for the 3 cities that we discussed above:
Dallas
Houston
San Antonio
The 2021 event clearly ranked as the second coldest event in the last 40 years. Only the storm of 1989 was colder and it had temperatures below zero in Dallas.
Conclusion
While this event was the coldest in the last ten years (and the last 30 years) it is by no means the coldest experienced by Texas residents. When studying the science of weather, it is always clear that weather events run in cycles and on occasion you can be hit by unlikely, but possible extreme events. However the question that remains for governments, businesses and individuals would be that of a cost/risk analysis and how far back should they be looking in time. Knowing the history of major cold events can help determine the overall risk of an event like this occurring.
If you were planning in Texas and managed on a 10, 20 or 30-year history, prior to this event you would have had to look down to the following date:
Doing your analysis you would have found Dallas at 13.9 degrees F in 2011. That value would have appeared as the coldest event you would be planning for. Only when going to the 40-year history would you have found the 1989 Texas event which shows an event below zero and colder than the 2021 winter storm.
More Information
If you need more information about specific historical weather data, near and long-term forecasts or historical statistical averages, please reach out to us at info@visualcrossing.com or visit https://www.visualcrossing.com/weather-data