2009 Superstorm Update

Local Update...
   Weather Models Raising Questions, And Causing Headaches...

Overview
     Weather models are now causing meteorologists, forecasters, and weather enthusiasts to have headaches, and throw there hands up in the air. What went from all medium, and long range weather models being in significantly good agreement for several days in a row, has now changed to a bunch of different possibilities. Overall, the one thing they have been fairly consitent on is a track further east. As far as strength they have all generally been weaker, but still significant. I am going to talk about each model, and what it shows. I will sum it all up with a summary in a few minutes.

NAM Model
     The NAM model which is a short to medium range model only going out 84 hours, is now beginning to get the storm in its sights. Although yes it has been picking up on its formation across the South Coast states the past several runs. It is now closing in enough on the storm to actually have in its sights what it may do for our area. So overall not much can be determined at this point from this model, but its general track brings it from its initial stages near Texas, across the Southeast States, and track North-Northeast literally on the edge of the coast. The storm at the models furthest forecast point of 84 hours, shows a disorganized area of low pressure off the New Jersey coast with a pressure of 1004mb. What happens after that, is unknown with the NAM until future model runs. One thing I would strongly suspect is that shortly after 84 hours the storm should begin strengthening, as the northern jet stream, will begin phasing with the southern stream energy. At this point the 500mb trough is in the neutral position, so as the phasing begins, it will allow it to start going in the negative direction.

     What this means in simple terms, as the weak southern stream system moves up the coast, it will begin to phase with the northern jet stream, and begin intensifing the storm, a bit later then the earlier long range models predicted. Resulting in a further track to the east, and a less intense storm.

     One thing with the NAM model, is as it gets towards the 84 hour mark, it becomes much less dependent. I am not saying its incorrect, but then again I am not saying its correct either. So at this point, I would prefer not to use this model past its 60 hour mark.


GFS Model
     The GFS model is a short to long range model, known for its long range of 384 hours. The model is also known as the most problematic model this year. This model seems to love to flip-flop the most. Although for a while, it was very consitent with this storm. Up until last night that is. The past 3 GFS model runs have shifted the storm significantly further east, and have significantly weekend the system, with no strengthening until near the eastern portions of Cape Cod or up into the Gulf of Maine. This model was one of the longer range models that indicated that this storm was going to be a storm to remember, tracking up the Appalachin mountains, with a peak intensity into the 964-968mb range. As stated above the most recent GFS model run is forecasting the storm to move out to sea, and strenthening much later then first thought, resulting in some light snow, and maybe some breezy conditions at best, the peak intensity the GFS is now forecasting is 980mb while just to the Northeast of downeast Maine.

     In simple terms, this model is indicating, a much weaker storm, moving further out to sea, resulting in significantly less precipitation, and wind.


ECMWF & UKMET Models
     These two models are mianly medium/ long range models. The two models had been predicting a very significant storm, very similar to the GFS original track, of up the Appalachin mountains, with a peak intensity of 965-975mb. These two models have trended further east, and weaker. With not much impact on the area. The UKMET indicates the storm moving so far east, not even significant clouds would effect coastal areas of New England from this. Both models now have this storm at peak intensity in the 996-1000mb range, well off the east coast.

     In simple terms, if these models were correct then either no storm, or just light snow would effect the area. The light snow being confined to far eastern Vermont.


DGEX Model
     This model is a long range model, and is actually a somewhat newer model. This model has been one of the more consitent for this storm so far, although this model too has shifted the storm further to the east, and less intense, but still brings significant precipitation to the area. In the previous post you can see an image of this model, at its prediction of the storms peak intensity of 959mb. The peak intensity from the most recent run of the DGEX model is now 975mb (much more believable) across downeast Maine.

     In simple terms, the DGEX model is most consitent with forecasting this storm so far. If this model held true, the storm would be weaker then this model first predicted, and would be farther east, but the potential for a significant winter storm exists.


Canadian & JMA Models
     These two models are generally medium range models, and have also been consitent. The JMA indicates the storm still to track up the Coast, and up the Connecticut river Valley of Vermont. The Canadian model has shifted east, but ends up over Central Maine. The peak intensity of the storm from these two models are in the 976-984mb range.

     In simple terms, if these models are correct, then a Significant winter storm remains possible for our region, with the potential for Blizzard or near blizzard conditions for portions of our area.


Comparison To The 1993 Superstorm
     This storm will not be like the 1993 Superstorm. That storm was literally a "Storm of the Century". It effected such a large area at one time, with signficant amounts of record breaking precipitation, wind, cold, and severe weather that caused such large amounts of damage. A Winter Storm like that we may never see again in our lifetime. With that said, from every post here on out, this upcoming storm will never be refered to as a Superstorm again, unless things change drastically. I apologize for naming this a Superstorm, but models did show the potential of a Superstorm.


Comparison To The 2007 Valentines Day Nor'easter
     The Valentines Day Nor'easter was a very significant Winter Storm. That storm too was one of rare occasion, but could definatly be seen again a couple more times in our lifetime. At this point models indicate that any potential snow totals will be no where near, that of the V-day storm. But then again models cant predict any mesoscale features this far out either. The current storm, if models come back in agreement on a track similar to that of the JMA, or Canadian, very well could match the V-day Storm, or be close to matching it.


Summary/ Forecast
     The one thing that can be guranteed is the fact there will be a storm. But the big question is, where it will track, and who it will effect? I will now dangerously put out my first official text forecast. Just to remind you, the post yesterday was the potential situation, based strictly off what the models had been showing. For this first official forecast, it has taken quite a bit of studying of models, and past research to try and figure out what is going to occur. Also of additional note, as stated above, this storm will no longer be refered to as the 2009 Superstorm, due to the fact, that no storm should be called a Superstorm unless its just that, a Superstorm. If it occurs it will likely be refered to as the "2009 Ground Hog Day Storm" whether or not it falls on the day of or the day of after Ground Hog Day.

     What we will likely see is a weak wave of low pressure form near Texas, and track east-northeast into the Southeast United States. Then the storm will begin moving Northeast up the coast, and begin to interact with stronger northern jet stream energy. The low pressure center should be along or just east of the coast, and slowly intensify until up near the NJ coast, in which it will begin to intensify more rapidly, and continue moving Northeast and into Central Maine. The storm will be continuing to intensify while over Maine. But the strongest pressure while still over the United States (Maine) will likely be in the 980-985 range. This track and strength will result in Snow for Monday Night and Tuesday. With significant snow accumulations possible, especially across eastern Vermont. Wind will likely be pretty strong, resulting in near Blizzard conditions for portions of the area.

     How I came to my conclusion for the track is based on the fact, that models are split, some show a track way out to sea, some show along the coast. What I did to base my descision was, I went with the track off the models that showed a more westerly track, and the fact that all the storms this year have tended to track further west. All in all, we will have to wait and see. Models will definatly change more between now and then, lets just hope some of the better known models, like the ECMWF, NAM, and GFS come into agreement on a storm tracking very close to the coast. Stay tuned.

(Sorry for any spelling errors, spell check isnt working at this time) =]]