Here’s how to see archived model runs of historic storms

The Blizzard of 2006 was a tremendous snowstorm in our local area. While it did fall in the middle of a warm and otherwise uneventful winter, it featured some tremendous dynamics and impressive banding. Do you remember what forecast models were showing prior to that event? Me neither. Up until now, it’s been fairly difficult to find archived model images dating back to the mid 2000’s, and even if you accessed them, the images were coarse and the graphics difficult to comprehend.

That has changed. Unknown to some, there is an easy and simple way to  access model data from the wildly popular free model data website at Penn State University. Known as “Ewall” to meteorologists and hobbyists alike, this website has been around for many years, and has served as a central hub for model data while remaining “new” to the times with upgrades and new graphics. The website also houses a freely accessible archive of model images dating back to 2004.

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Nantucket now has awesome slush waves

It’s so cold, the ocean is freezing over! No, not really. But parts of it are, especially shallower areas and the top layer of the water near the beaches of Nantucket. This phenomena hasn’t been seen in many years since, well, it hasn’t been this cold in many years. But the prolonged record breaking cold air which settled over the Northeast US over the past 30 days has brought some incredible sights. The Hudson River has large masses of ice floating down it, and now the beaches of Nantucket have “slushy waves” crashing onto the shore.

These waves are the same as any other ocean wave, except for the fact that the surface of the ocean is covered with slushy ice. The top layer of the ocean waters are very close to freezing over — but the temperature of the water isn’t quite supportive of that especially given continued water movement and the waters depth. So what you get is a layer of slush and pockets of icy water on the top, creating an amazing scene as the waves crash ashore. These are known in the area as “slushy” or “slurpee” waves.

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Hail, waterspouts and rainbows all made an appearance today

A developing coastal system produced an array of weather conditions throughout the area today. Beginning in the morning, showers and thunderstorms developed as a result of daytime heating at the surface and cold air moving in aloft. The developing system aided in lift which allowed for these storms to form. The cold air aloft, meanwhile, aided in not only the storms development, but the threat for some hail. As the storms progressed through parts of New Jersey and then out to sea, some low level shear allowed for waterspouts to develop.

When colder than normal air exists in the mid levels of the atmosphere, developing thunderstorms will often produce hail as the ice in the cloud becomes much more thick than usual due to the colder temperatures. This often occurs in the transitional seasons of Spring and Autumn in our area, when cold pools move overhead and the surface can still become unstable.

Meanwhile, scattered showers and storms continued to develop throughout the area during the afternoon hours. Multiple rainbows were seen throughout the area. Currently, a convective system south of Long Island is moving northward toward the Central and Eastern parts of the Island. Stay tuned to our Twitter account for up to the minute information on these storms.

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SPC Outlooks will change starting this Wednesday

The Storm Prediction Center has used the same risk categories for a large part of most of our meteorological careers. Although they have adjusted the probabilities, percentages, and yes even the colors — the categorical risk areas have remained the same. On this coming Wednesday, that will change. The Storm Prediction Center currently uses a simple categorical risk system which highlights the potential for severe thunderstorms across the country. The risk areas of Slight, Moderate and High are triggered by percentage chance of a type of severe weather within 25 miles of any point. And while the newer outlooks also highlight the potential for general non-severe thunderstorms across the country, Wednesday will mark a dramatic change in the way these outlooks are viewed and understood.

The main change will be the addition of two risk levels, both falling on opposite sides of the “Slight” risk of severe thunderstorms. “Marginal”, a new risk category, will highlight the potential for severe thunderstorms that includes a 5-10% chance of wind and hail and a 2-5% chance of tornadoes — but does not trigger a Slight Risk. “Enhanced” falls on the other side of “Slight”; in other words the risk levels are enhanced (30-45% risk) but not organized or widespread enough to trigger a Moderate Risk.

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