Influence of Warmer Than Normal Waters on Northeast Snowstorm

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The SSTA pattern is very warm. Easterly component of wind will increase the amount of moisture flowing into the developing storm. Heavy rain causing a flood risk is likely in east/northeast Virginia to southeast Maryland while well inland where temperatures stay cold over-achieving snowfalls will occur.

Highlight: Warm SSTA will have a major influence on the Northeast Corridor Storm: Adds moisture to cause large amount of precipitation, helps to warm the coast to cause mixed precipitation or all rain and warm SSTA = sea level rise which will increase dramatically the coastal flood risk.

Fig. 1: Latest snowfall forecast with annotated max wind gust forecast.

Fig. 2: Offshore warmer-than-normal waters will have MAJOR implications at the coast with this storm.

Fig. 3: NOAA/NWS latest weather watch, warning and advisories. Winter Storm Warning in the Mid-Atlantic will expand to New England.

Discussion: Snowfall forecasts are increasing across Pennsylvania. In this location the storm produces ALL snow and given proximity to an energetic upper-level cold trough coupled with higher terrain causes 2 foot of snowfall risk. Pennsylvania is looking at blizzard conditions with this storm.

The SSTA pattern is very warm. Easterly component of wind will increase the amount of moisture flowing into the developing storm. Heavy rain causing a flood risk is likely in east/northeast Virginia to southeast Maryland while well inland where temperatures stay cold over-achieving snowfalls will occur.

The warm SSTA produces other major issues. Specifically, warm SSTA also means above normal sea height. The east wind pushing the water surface to the coast will be significantly higher and coastal flooding more significant. Areas affected include Delaware, Delaware Bay, New Jersey, possibly the NYC (Lower Hudson), Long Island and southeast Massachusetts.