Today’s rain will instantly freeze this afternoon, meaning salt will not have time to take full effect, that’s the warning from Lincolnshire County Council.
Known as a “Flash Freeze”, the weather condition where temperatures plummet within 30 minutes of rain stopping, only happens once or twice a year.
It means motorists are being strongly urged to take extra care and expect icy surfaces, especially into rush-hour.
Full, countywide gritting runs are currently taking place from Noon, but the rain washes much of the salt off the surface.
Several further runs, including an extra one for hills, will take place through the remainder of Thursday and into the night.
Darrell Redford, winter maintenance engineer, said: “As rain washes grit away, it’s normal practice to wait until the rain stops and then treat the roads in readiness for falling temperatures later.
“What we’ll see this afternoon is a “Flash Freeze”, meaning those icy temperatures will arrive within 30 minutes of the rain stopping, so we simply won’t be able to get the gritters around everywhere in time.
“We’ll be out in full force, salting the roads constantly as the day and night progress, but it’s absolutely essential that motorists expect icy road surfaces and drive with the greatest of care.
“Likewise, pedestrians should tread extremely carefully.”
The county council is also warning that temperatures may reach -9 degrees celsius in some areas, the area where salt starts to become less effective in any case.