5 Nov 2012

Nor’easter threatens rain and gales for east coast of US

Last week, Hurricane Sandy battered the east coast of the US with heavy rain, damaging winds and a storm surge that caused devastating floods along the coastline.

Sandy has left more than 100 people dead, millions without power, and road, rail and air networks paralysed by the trail of destruction that the storm left in its wake.

While the weather since Sandy struck has been relatively quiet, allowing the clean up efforts to begin, this could be set to change midweek as an area of low pressure runs along the east coast of the US.

Forecast rainfall totals for the next five days from NOAA

Nor’easter

Although there have been fluctuations in the weather computer models, there has been a fairly consistent signal in recent days for a nor’easter to develop.

A nor’easter is a low pressure system that gets its name from the fact that it travels along the east coast of the US in a north easterly direction and has brisk north easterly winds on its northern side.

Such storms can bring problems for coastal areas in particular, with a risk of flooding, coastal erosion and gale or severe gale-force winds.

They can also deliver quite a bit of rain and even snow if the weather system interacts with cold air.

Possible impacts midweek

The first thing to make clear is that this nor’easter isn’t going to be anywhere near the scale of Hurricane Sandy as it isn’t a tropical weather system.

However, it will bring as much as one to three inches of rain along the coastline, accompanied by a strengthening east to north easterly wind.

The wind along the coast during Wednesday and Thursday could reach 40-50mph, with gusts of 30-40mph inland.

Although these wind strengths are not as severe as last week, it has to be remembered that a lot of trees, buildings and other structures will have been loosened by Sandy. As a result, even a lower threshold of brisk winds could tip the balance and caused further problems locally.

For those homes still without power, strong winds midweek could temporarily hamper efforts by electricity companies to fix power lines.

Coastal areas that had their flood defences damaged last week by Sandy will be at risk from minor to moderate flooding as the nor’easter creates a brisk onshore wind – something that the National Weather Service has highlighted in its latest hazardous weather outlook.

Quieter and warmer next weekend

Although midweek onwards is looking unsettled for a time, once the nor’easter has moved through, high pressure will build at the weekend.

This will bring much quieter weather, with light winds, sunshine and a rise in temperature. In fact, from the Carolinas to New York, temperatures are likely to be in the high teens or low 20s Celsius by early next week.

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