John Metcalfe was CityLab’s Bay Area bureau chief, covering climate change and the science of cities.
Warm temperatures are expected this weekend, and that's not good.
Imagine taking miles of 6-plus feet snow and sticking it under a heat lamp. A natural version of that process will be happening this weekend in the Buffalo area, and forecasters are warning it could create flooding in waterways and even entire towns.
Things are still white and icy in western New York, thanks to frigid temperatures pounding lake-effect snow these past few days. But the mercury is expected to creep near 50 on Sunday and kiss 60 on Monday, and that snow is going to undergo a rapid and torrential meltdown. The Buffalo office of the National Weather Service is telling people, especially those in places with several feet of accumulation, to prepare now for the possibility of "significant flooding." Here's part of its message:
TWO SIGNIFICANT LAKE EFFECT SNOW EVENTS THIS WEEK HAVE BROUGHT A VERY DEEP SNOWPACK ACROSS PORTIONS OF WESTERN NEW YORK. THIS SNOWPACK NOW STORES A LARGE QUANTITY OF WATER. AFTER THE LAKE EFFECT SNOW ENDS...A WARMING TREND IS EXPECTED TO START EARLY THIS WEEKEND.... A SOUTHERLY BREEZE AND RISING DEW POINTS WILL MAKE FOR A MORE EFFICIENT MELTING OF THE SNOWPACK.
AT FIRST THE SNOWPACK WILL ABSORB MUCH OF THE WATER FROM THE SNOW MELT. HOWEVER AS THE SNOWPACK RIPENS...AND WITH THE ADDITION OF A HALF INCH OR SO OF RAINFALL SUNDAY NIGHT AND MONDAY...THE POTENTIAL FOR FLOODING WILL RAPIDLY INCREASE.
The agency's Eastern Region Headquarters also has its eye on the problem, noting that the snow continues to pile up. "The deep snow that has already accumulated earlier this week has the equivalent of 2-5 inches of water—and this does not count the snow that will fall over the next 36 hours," it wrote yesterday. "Rapid melt of this snow could cause flooding of the streams and creeks in the metro Buffalo area and areas to the south where the greatest snow has fallen."
The good news is there's institutional experience in the region with this kind of situation. In 1942, heavy rain and melting snow combined to swamp roads and farms with floodwater, killing cattle, turning hundreds of basements into swimming pools, and washing out 13 bridges in one county alone. Disintegrating snow again flooded the land in 1963, damaging homes, and in 2006 a freak lake-effect storm dropped tons of dense, wet snow that quickly melted, causing flooding around town (some of that is pictured above).