Any Sign of Spring?

By now you have heard all about the “warm up” that is coming. Not that I want to dampen the hope that it will warm up at all, but the following points ought to be considered:

1)      Cold air to our north will fight against any major warm ups.  Mon night/Tue morning weather will be a great example.

2)      Deep snow cover will tend to keep things cooler. It helps to keep the surface air colder. Think about it as it makes a lot of sense.

3)      Any warm up this winter has been short, with the cold returning.

All the above makes me a little nervous about all the hype of “warm up … warm up” that I am hearing. Yes, it will warm up, but could we get cold air dammed at the surface, and all the mild air flows over us at 5000 ft?  It could happen. It has happened several times this winter. If we lived near Pittsburgh, I would be calling for 50s to near 60 over the weekend. But we are east of the mountains, thus cold air can get stuck or dammed behind the mountains, and the warm air just flows over the top.

Flooding?  I do not think it will be a concern at this time. Snow can act like a great sponge. It will absorb, and will temps not too far above 40 it will not melt that fast. But it is a concern when you have the amount of ice we have on the water ways and the amount of snow/ice on the ground. I imagine it will be a problem at some point this spring. And yes the cold will return again, starting next Sunday. But first things first …

Monday night/Tuesday morning snow storm. Yup, another one. The last one in a long line of snow producing storms. This storm will move from the plains east to the Mid Atlantic Coast. A good path for moderate to heavy precipitation, as it feeds off of the building warmth to our south, meanwhile our temps will stay cold allowing for all snow. Right now the US models are stringing it out because they are rushing it (as is normal for them) while the whole slate of foreign models are hitting us with 6+” of wet snow. I am leaning toward the foreign at this time, thus my snowier forecast.  

This storm will be a quick hitter. It will come in during the later night Mon and end by mid morning Tue. That means it will last about 8 hours. Pretty short window, but it could be a pretty intense window at that. It will turn mild after this with maybe a rain shower Wed, followed by potentially wet Thu/Thu night, mild Fri, then cooler Sat/Sun with some heavy rain possible at this time.

Details:

Sun: Cold, partly sunny. Flurries possible late, then clearing at night. High: 22. Low: 4

Mon: Beautiful to start with bright sunshine, until clouds roll in during the afternoon. Snow arriving toward midnight. High: 26. Low: 22 but rising toward morning.

Tues: Heavy snow ends very early in the morning. Turning partly sunny. Milder. High: 40. Low. 29.

Wed: Clouds and sun. Perhaps a rain shower. Not so cold. High: 42. Low: 26

Thu: Increasing clouds. Rain arriving. High: 42. Low: 40 with temps rising late to near 50 by morning.

Fri: Breezy, mild. Sun and clouds. High: 52 early but slowly dropping late. Low: 30.

Sat: Cooler with lots of clouds. Some heavy rain is possible over night. High: 38. Low: 35.

Sun: Rain ending. Turning mild then colder late. High: 42. Low: 28. 

Looking at the picture to the left, you can see my concern over the warm up. This is the forecast for Sun at 500 mb (way up in the atmosphere). 
The air flows between the lines 

The dip in the lines in the center of the US, is called a trough. It looks like a cup. If you notice it is tilted toward the east. This is called a positively tilted trough. This means that arctic air will press SE. This could undercut our warm up over the weekend if it presses even more. This will be updated. 

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