Friday, January 21, 2011

Crazy night on the models-- MONSTER low possible.

First issue-- I never updated this blog for the "snow threat" last night because I was never impressed with this storm. In a perfect world for snow lovers, we could have gotten a trace, but it never looked good. I'm always available via facebook if any questions do arise. (Keith D. Huffman, if your reading this via a friend)

We do have a legit storm to track-- and even if it ends up as rain the rain is WELL needed. This evening the models all showed a great consolidation of 500mb energy and create a MONSTER of a storm. However, the storm is just a SMIDGE west and for LYH east, its snow (couple inches) to heavy rain, ending as snow. (Maybe another couple inches)

Rain?? Yes--This storm could be an 1-81 special where all of 1-81 in VA gets SMOKED. Tonight's literal data showed about 18 inches or more along 81 and it drops off rapidly east of there due to mixing with and changing to rain.

Why- We have a great cold air mass in place, but it is leaving just as the storm approaches. This creates two issues. First, we are losing the cold air support and secondly, this is more conducive to a low that tracks JUST inland.


Looking at the above map-- If the H noted just east of Maine was sitting back 300 miles to the west, we'd have an all snow set up. As that H has been moving east, the cold air is also moving out. 

This is a VERY wet system. 
A region wide 1-2 inches of precipitation.



Note: Nothing is in stone yet and much can change as we watch this storm evolve.
So, this is something to track. 5 days away so plenty can and will change. The data takes the low from near Myrtle Beach to literally just on top of us.  Reality is that it could be 100 miles either side of that line and that the thermal profiles could be a few degrees off either way as well. So, the next couple days we work on track and exact temps. Lastly, if the energy aloft (500mb or 18k feet) doesn't phase or work together, we have a low but much weaker.

Teaser- Tonights ECMWF was all snow in Roanoke and 15+ inches. In LYH, it starts as snow and just about the time it gets really heavy it mixes with and changes to rain. 2-4 inches has already fallen. Rain is heavy and water is logging down the snow Almost an inch of rain falls during this time period. While the change to rain was a slower process, the switch to back to snow comes with rapid force and snows heavy. Temps are just above freezing and the snow struggles to accumulate at first. Another 2-4 inches falls on the back side. Temps slowly drop and as it ends in flurries, we are at 30 degrees and drop into the mid 20's Wednesday night. The slushy mess freezes into skating rink.






1 comment:

  1. Let me add, sleet and freezing rain could very well end up being a big part of this storm too.

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