Saturday, April 12, 2014

Saturday Evening Flood Update: Vermont, New York, Michigan Under The Gun

You'd never know it if you were outside in northern Vermont today, but a cold front settled into the region.
Spring flooding gets close to a house near
Enosburg, Vermont in April, 2011.  

It stayed gorgeous, with sunshine and temperatures near 60. All the front did was subtlely shift the wind from the south to the west, and slowed the pace of rising temperatures a little bit.

That front is stalling, and people in northern New York and northern New England are actually going to really start noticing that wimpy front that arrived on the scene Saturday afternoon.

The front will go from wimpy to at least semi-wild. Showers and springtime's first thunderstorms will ride west to east along the front Sunday as the front itself slowly works its way back north toward Quebec.

This can turn into a dicey situation, believe it or not. In the spring, these slow fronts, separating the first surge of summery air to the south and seasonably chilly air to the north can squeeze out a lot of rain.

The most extreme example I can remember of this kind of west to east front in the Northeast was in late April, 2011. A huge tornado outbreak was brewing over the southern United States, and it was hot and humid down there. To the north of the front, it was cool and damp.

Along this front, wave after wave of strong thunderstorms passed over Vermont, armed with heavy downpours, vivid lightning and torrential bursts of hail.  (You can see a video of the one of the thunderstorms from this outbreak, on April 26, 2011 as it pelted my deck in St. Albans, Vermont with TONS of hail)

This combined with warm temperatures and a lot of snowmelt, caused some very damaging floods in northern Vermont, especially along the Lamoille River.

I don't expect anything that extreme Sunday, but I still wonder if the front will inspire showers and storms that will dump more than the quarter to two thirds of an inch of rain that is forecast on Sunday.

All this could start to trigger flooding across the Adirondacks, northern Vermont and northern New Hampshire by Sunday afternoon.   Areas more to the south will be away from the front, so it won't rain as much and flooding won't be quite as big a worry. (Still, watch for lowland flooding as early as Sunday along the Otter Creek in Rutland County.)

As of late Saturday afternoon, some pretty heavy downpours have developed in Michigan, where there are flood watches. These are some of the storms that are expected to hit northern New York and northern New England Sunday.

By Monday, the front will have lifted into Quebec and near record temperatures will come in. Towns like Burlington and Rutland, Vermont and Glens Falls and Albany, N.Y. could reach 80 degrees. There probably will be little if any rain on Monday, but such warm temperatures will really melt snow of the mountain sides fast, keeping river levels high.

Finally, on Tuesday, we're still expecting that slow moving cold front to come through New England. If the rain and thunderstorms with that front are as heavy as some forecasts indicate, there could be some substantial flooding.

It probably wouldn't be anything on the level of Tropical Storm Irene in 2011, but the water could get high enough  Tuesday to cause some damage.

As they keep saying, pay attention to future forecasts and possible warnings.

I'll offer an update first thing Sunday morning.

1 comment:

  1. I have to say, I'm starting to dread your updates Matt!! Endless winter, torrential rains, flooding, are locusts next? :-)