Daily Archives: March 21, 2014

Really Cool Graphic – Frozen Great Lakes

It may be spring now, but it certainly doesn’t look or feel that way for the Great Lakes, most of which are still ice-bound. Superior, Huron, and Erie are still almost entirely covered by ice, while Michigan is less than half covered. The only lake not ice-bound this winter has been Ontario at the far-right. Image from LANCE MODIS taken on March 16th.

You may be wondering why Lake Ontario is the exception to the frosty rule here. Ontario’s average depth is about 283 feet, only Superior has a greater average depth (Erie is the shallowest, so even though it’s further south than Ontario, it’s often the first to freeze). Furthermore, Ontario is located at a lower latitude than Superior and Huron, and it’s relatively smaller surface area maximizes its heat retention.

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NYC Weather Update – March Snowstorm? Mar 21, 2014

This is not the news any of us want to hear, but confidence is increasing for a potential late-March snowstorm to impact the NYC area next Tuesday-Wednesday. First, the weekend forecast:

Saturday

A warm front will push through early Saturday followed by a cold front later in the day, with a slim chance for precipitation. After the passage of the warm front, gusty winds will increase from the south and southwest, ushering in some much anticipated spring-like warm air. High temperatures may top 60, but with mostly cloudy skies and the influence of the wind it will feel cooler.

Sunday

Clouds will diminish Sunday, but in the wake of the cold front, temperatures will struggle to hit the low-mid 40s. Polar high pressure continues to build overnight, with low temperatures much below average only in the mid-20s!

Monday

Fair conditions with the polar high in control, temperatures will only be in the mid-30s, nearly 15 degrees below normal for this time of year.

Tuesday and into Wednesday

An area of low pressure forecast to form offshore of the Carolinas will track into our area. Forecast models are pointing to this system rapidly strengthening with a sharp decrease in central pressure as it progresses into the waters off of Long Island. Recent model show a track closer to the 40N/70W benchmark, which increases the potential for a significant snowstorm. However, 5 days out, there’s still a good deal of uncertainty as to final track, positioning of precipitation bands, and available moisture. A track slightly further north will mean increased odds for a significant snow event, while a track too far north or south will diminish these chances.

GFS model showing a strong low pressure center consolidating southeast of Long Island around 1AM Wednesday morning.

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GEFS model (spaghetti strings show upper air circulation 552mb and 564mb). The two main bunches of the strings represent the polar and subtropical jet streams respectively. Notice the loops connecting the two streams over the our region. This is converging of energy from both streams will feed the rapidly deepening low pressure center.

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