Ph.D. Student - Earth System Science (UC Irvine), B.Sc. - Atmospheric Sciences (Cornell University)
By: Zachary Labe , 3:35 PM GMT on December 24, 2007
Long Term Outlook
Well good morning and Merry Christmas. It seems many of the forecast models are predicting a major storm for the first couple days of January and some models are even predicting snow for the 31st of December, which is also something to watch. Well one thing is for sure it appears a extremely frigid arctic airmass is going to move south for the first week of December. If some of the models are right then it is cold enough to snow in places like Austin, Texas. Check out this model run for January 2.
Wow that is cold. The -10degree line is all the way to the gulf coast. And look at that high over Utah, 1056mb, that would create horrible and record breaking Santa Anna winds. With this extreme contrast in temperatures something is bound to develop somewhere. Now the 06z run of the gfs does not have the coastal low like previous runs, it does have a blob of heavy precipition of the southeast coast. Also this model shows heavy lake effect snow stretching all the way to Tennessee. This all is the perfect set up for something big to happen. The ingredients are there except for the NAO.
Also for my last morning thought, did anyone check out the NAM. It shows the coastal low a little closer to the coast. It even prints out .25inch-.5inch of the cape of MA. That would probably be mostly rain, though. The 0degree celcius line is too far north for any parts of MA to see all snow.
**Update as of 1230pm
Well the new 12z gfs is in and.......well it shows a powerul front moving in across the region with rain on the front end then snow on the back end. No coastal low is shown. But, for the 4 of January it has a major coastal storm, except though it is far out to sea and does not affect anyone. So my take on all of this is that the GFS is confused. I think it senses there will be a powerful storm around New Years. It is getting confused because of this unbelievibly strong arctic air mass moving into to most of the country. Here is the 12z GFS map for January 4...
I believe there will be a storm somewhere across the country. The air masses are going to collide creating a big storm, whether it is just a strong front, a low that heads up through great lakes, or a coastal low. We do not just yet know. It is still a long ways away. My only worry is that the NAO is becoming neutral or positive. That is one limiting factor of why we might not see a coastal low. La Nina years are strange years. The winters can be hard to predict, but one thing is for sure many La Nina years have created some powerful storms in the past.
**Update as of 400pm
Well I took a look at the 12z run for the EURO model and it shows some interesting things. First it keeps showing the coastal storm for the 26 of December, affecting mainly coastal areas of New England. But it looks like mainly a rain storm. Then it shows a relatively strong coastal low for the 31 of December. Check it out...
Then after that storm it appears for the first week of January storm it has a strong front move through with a low developing on that and heading north. It shows the coastal low being farther west and bringing in some warmer air to some areas instead of all snow. Here is the 12z EURO for January 3...
So for now I hope everybody has a wonderful Christmas, and I might have an update sometime late tommorrow morning.
***Christmas morning update...
Well this is going to be my one and only update today. I looked at all of the models and the all agree on a coastal low for this week especially thursday. The NAM prints out more precipitation for inland areas while the gfs keeps it a little more out to see. This storm will be interesting to watch, there could be a surprise or two before this storm is said and done. This weekend all of the models agree on a rain storm for saturday. Then for the 31st there is some disagreement. The EURO develops a coastal low and brings snow to many areas, while the GFS brings a storm through the Carolinas and out to sea delivering a little snow for areas north of Baltimore and south of State College. The NWS for my area says their gut feeling is a storm will head farthur west with everybody getting rain. Remember there is no real cold air during the time of this possible storm. Here is the 0z EURO for the 31st...
Also the for the first week of January the models all agree on a large arctic outbreak, but there a lot of disagreements about a large storm next week. So we will have to wait and see.
Also I just checked and the 12z NAM comes in with .1inch-.25inch of precipitation over the state of Pennsylvania for Thursday's wave and it shows the 0degree line at the mason-dixon line. This maybe something to watch for a inch or two of snow across the state of Pennsylvania for Thursday.
Also I updated the NAO above and as you can see it goes slightly negative around the 1st of January, then it goes highly positive.
Have a wonderful day and Merry Christmas!
**Update as of 400pm...
Quick update. Well the 12z run on the EURO shows only rain for the middle atlantic for the 31st, but it still maintains the arctic airmass. Also the 18z run on the NAM prints out moderate precipitation over the middle atlantic coast line for the 26th storm. And it shows a wave bringing .1-.25inch of precipitation over Pennsylvania. That would probably be snow or a mix of rain/snow. That will be something to watch for maybe a surprise inch of snow over PA. Though the NWS's seem to think it will all be rain, even in the north. We will have to watch it.
Check back shortly, this blog is in progress...
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