If winter had a “looks can be deceiving” moment, it would be freezing rain: it falls like ordinary rain, then turns streets, steps, and tree limbs into glass.
Corridors of more intensive snow, zones of inhuman cold can be predicted on forecast maps, yet the most problematic winter configurations have one common denominator, i.e., ice. With the most recent multi-state storm pattern, forecasters pointed out two primary icing corridors; one of them extending eastward to Texas through Kentucky and the other one along Georgia to Virginia due to the fact that its effects pile up easily. Ice is not only slippery but also heavy and it is the heavy part that makes a hard weekend a long recovery. This is why the National Weather Service described some of the freezing-rain threat as “crippling” and “catastrophic,” and travel interruptions can persist well beyond radar clearance.
It is not physics, but hype. Freezing rain is a phenomenon whereby a fine coat of subzero air hugs the earth such that droplets remain in liquid state until they collide with a cold surface and then they are frozen at the point of collision. Sleet is different: raindrops freeze into pellets before being deposited, and this still makes the roads oily, but does not pack up trees and power lines like that. The difference is important as there is a “sound” that a neighborhood may make of the danger, the sleet may be pinged and bounced, the freezing rain may remain an invisible film until the whole scene starts glittering.
The accretion of ice does not have to be deep in order to be destructive. Meteorologists generally consider half inch as a threshold before massive damage occurs; other predictions about this family of storms had been 1-2+ inches of ice in the most prone areas, which can be disastrous to the branches and span over a mile. When the lines are downed, the risk of outage turns into a health danger, since cold snaps are often the aftermath of the precipitation. According to Jim Cantore, it was described as having an overlap in a very straightforward way: Ice accretion as much as an inch or more could happen in some areas and that would be more than enough to bring down trees, power lines and even whole transportation systems.“The real concern is that this doesn’t end when the precipitation stops – an Arctic air mass follows, locking everything in place for days.”
The household priorities are shifted by that lock-in effect. Homes also may lose more than heat when temperatures remain below freezing over a number of days, as the office at Fort Worth cautioned they might happen in Texas. The office wrote that any power outage will exacerbate the damage to pipes that would be endangered by extreme cold this weekend, where the freezing limit could continue to be below zero in central Texas and 3.5-4 days in north Texas. Pipes, pets, medicine storage, and charging are also included in the checklist along with road conditions.
Travel is also not the same during the ice storms as it is during snowstorms. Snow can be cleared by plow, however, ice tends to be more resilient to mechanical cleaning and bridges and overpasses are the first places of failure since they are covered with ice on all sides. Texas NWS meteorologist Nicholas Price gave an overview of the real hazards: “bridges and overpasses being frozen over,” plus “trees and various different things that could fall into the roadways or potentially fall on houses.” Cascading cancellations may be experienced at airports that serve major southern interstates, where ground crews may have a hard time de-icing and maintaining ramps in a safe state.
During such storms, the forecast map is just a start. The larger one is that a small section of freezing rain can cause a broader, more protracted imbalance–when cold sourness is brought in its wake and all is held in suspension.
