It is April 18. Instead of warm spring days, flowers blooming and birds singing, the Northeast is bracing for a big blizzard – at least for the time being. height.

Snowstorms in the Northeast in April aren’t exactly unheard of, but they seem to have been more common 20-25 years ago when I was growing up in Pennsylvania. Not that they still don’t happen, of course they do. Just that the snowfall in April or even May isn’t too big of a surprise compared to now in our warming world.

I suppose it’s all a matter of perception. When you yearn for warmer weather, it sometimes seems like it’s much colder than it really is. Small snow events can seem much bigger to someone entirely in winter.

Retrospective Monthly abnormal temperature in April since 1981, April cooler-than-average weather is only slightly more common before 2000 than after 2000. Now, not all April days are cooler than average. Those jars all have blizzards, but you’ll get to my goal with this one.

Anyway, back to today.

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An area of ​​low pressure over the Carolinas will hit the coast this morning. In doing so, it will merge with an eastward moving trench over the Great Lakes region. Result: a Nor’easter.

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Unfortunately for late-season coastal snow lovers, the heart of the lowlands is forecast to track inland. Coastal New England will be on the warm side of the storm while elevations of the Northeast will be in the cold.

I mentioned before that this is going to be a big storm for altitudes.

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Altitude has the advantage that it is naturally colder when you are above sea level.

Inevitably, there are two peaks clamping this storm – a strong peak ahead of the storm and a weaker, wider peak behind – both of which will push cold air south. However, the air near the highland center is not that cold. After all, it’s April and the temperatures are rising. Once that air transforms as it moves south, it will be near zero around the freezing point. Valleys where temperatures are naturally warmer will still have snow through dynamic cooling (moisture evaporates into the drier air, lowering the temperature), but altitude will be the big winner.

The elevations in central and upstate New York are the biggest winners as they will get their total boost from the snow lake effect on the back of the system in addition to the initial rain. There can be more than one foot total here.

Also notable are the potential half-foot buildup in the Alleghenies of central/south central Pennsylvania and the Pocono Mountains of eastern Pennsylvania. Again, backflow and naturally colder conditions really help here.

It should be noted that with temperatures so low, this will be a particularly wet heavy snowfall. You know, one of those blizzards with big, flooded snowflakes. This accumulation of thick snow on power lines and trees can knock them down, causing power outages. Be prepared to stay warm if the power goes out.

One good thing about snowfall in April is that it doesn’t tend to stick around for too long after that.

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Although the valleys will be back above freezing by Tuesday afternoon, everyone, except possibly the mountains themselves, will be above freezing by Wednesday afternoon. Escalating temperatures plus April sunshine will likely lead to rapid melting.

Some rivers in this area, especially in East New York, are nearing the flood stage. It is possible that a sudden thaw could push some sites into a period of low-level flooding. Either way, it’s something to keep in mind if you live in a vulnerable area with a river near flooding.

If you are a snow lover, enjoy the last snow of the season! If not, fine, just keep. Soon in the summer.

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