Accumulating historical data, particularly on El Niño and La Niña conditions, provide some idea on how the coming winter will affect us – and our streets.
Predicting the weather is regarded as an inexact science. But from when the first Farmer’s Almanac was printed in 1792 until today, the tools for doing so have improved considerably. The wooliness of caterpillars, early geese departures, and rings around the moon are giving way to sensors, satellites, Big Data, and algorithms that give us a little more accurate reading of what we face in the months ahead.
So as a service to anyone tasked with preventive or reactive pothole maintenance, and all users of roads whose lives are affected by potholes, we present our mostly-annual prediction of pothole-inducing weather for Winter 2017-2018.
Overriding winter weather conditions for 2017-2018
The prevailing factor for most of the U.S. and Canada is we are in a La Niña year. This is the weather phenomenon that typically follows an El Niño year or years (the last El Niño was considered major, lasting from 2014-2016, although 2016-2017 was a transition year presenting a weaker-than-average La Niña). In broadest terms, it means colder and wetter weather in the northern sections of the country (to a greater degree in the Pacific Northwest), but warmer and drier weather conditions in the Southeast (including Florida), the southern portions of the Great Plains and the Rocky Mountain region.
Something that might alter this is atmospheric blocking, a high-pressure system in the Pacific or Arctic regions that divert weather elsewhere. This phenomenon basically caused the dreaded polar vortex in the winter of 2014.
From a pothole perspective, that suggests the northern tier of the country, from the Pacific to the Atlantic, will have a greater number of potholes by springtime of 2018. The opposite would likely be in the case* of regions stretching from Los Angeles to Miami with Dallas in the middle.
Cities most likely to get potholes this winter
Drilling down to the specifics, here is where things look for potholed streets come March of 2018 (and, likely, before then):
Probably good: Cities that likely will have a minimum of weather-related potholes will be Phoenix, Tucson, Albuquerque, Taos, Santa Fe, Denver, Dallas, San Antonio, Austin, Houston, Galveston, New Orleans, and Baton Rouge. This is due to above average and drier conditions.
Possibly good: Cities that might do ok this winter in the pothole department include Los Angeles, Las Vegas, Salt Lake City, Oklahoma City, Lincoln (Nebraska), St. Louis, Little Rock, Mobile, Birmingham, Nashville, Knoxville, Lexington, Indianapolis, Cincinnati, Washington D.C., Virginia Beach, Norfolk, Charlotte (North Carolina), Raleigh, Charleston (South Carolina), Columbia, Atlanta, Jacksonville (Florida), Orlando, Tampa-St. Petersburg, and Miami. In these cities, the news is that they will have average or slightly above average temperatures.
Possibly or probably bad: Cities where potholes might be costly, slow traffic, and lead to accidents are Seattle, Portland (Oregon), Boise, Billings, Fargo, Minneapolis-St. Paul, Milwaukee, Madison, Green Bay, Chicago, Detroit, Toledo, Pittsburgh, Buffalo, Rochester, Syracuse, New York City, Boston, and Portland (Maine). In Canada, Toronto and Montreal are expecting higher than average precipitation, less so for the Maritime provinces. Temperatures in these cities will be average or slightly below average, and wetter than average (keeping in mind it’s moisture in combination with freezing temperatures that breaks up pavement).
Words of pothole caution
But potholes are not just a result of cold and wet weather: It’s the oscillations above or below freezing that expand and contract with moisture in asphalt cracks. So from that perspective, the potholes might be more abundant in areas where warmer and colder conditions meet.
Where will that be? Again, it’s hard to predict and potholes can happen in places where the temperatures never go below freezing. Honolulu consistently ranks poorly in road quality assessments, surprisingly putting it in the same bucket as Chicago, Boston, New York and Newark, New Jersey. Houston ranks poorly as well, while the nearby city of Corpus Christi, Texas gets high marks overall for its traffic and other transportation infrastructure ranks. The amount of traffic, the degree to which preventive maintenance is undertaken (things such as crack sealing and repairing smaller potholes before they get bigger), and simply the passage of time all affect pavement integrity.
Also, just simply saying “we’ll have a mild winter” can only provide a small amount of comfort to motorists who want to avoid $800 cracked catalytic converter damage from a pothole. “Mild” in the Midwest and mid-Atlantic regions might mean temperatures in the mid-20s to mid-30s (degrees Fahrenheit). The problem there is the freeze-thaw cycles might happen with greater frequency, promoting the expansion of cracks and undermining the subsurface of asphalt roads at an accelerated pace. Cities that fall into that freeze-thaw zone can be Atlanta, Dallas, Omaha, St. Louis, Kansas City (both of them), Indianapolis, Irving (Texas), and Reno.
*The great variable is preventive maintenance. Two cities in the same region with very similar weather conditions might have very different roads. The website WalletHub assesses pavement and other components of streets and traffic infrastructure rank the top 100 most populous cities.