Tuesday, December 7, 2010

See the STORMTRACK page

There is now a special STORMTRACK page up for totals from this storm.

Storm Track (NCEP/EMC)

Even though the line of heavy snow is usually just (in this image) up to Central Illinois, this storm is a monster and will likely bury people as far up as Chicago or Milwaukee. It's all very hazy.

Preliminary Snowfall Storm Accumulations

Image from HPC.
This is the PRELIMINARY precip translation into snowfall accumulation from the storm in the storm's snow:water ratio is 10:1 inches.

Based on this, I believe that the storm could be quite a disruption up in the Lower GL.

Official Forecast For Sunday Storm 12/7 update

The below is the storm tracks possible for this storm.
The below track is the individual track.
The below track is the more likely storm track at this time. But it can change.

At this time, because the storm is so far away, I am not naming a certain track likely. But models are indicating that the latter storm track is more likely.

Significant East US Storm This Weekend.

This is the Weather Centre's Chief Meteorologist Andrew, here to give you the latest information on this developing intense storm.
We're going start out with some models, preferably the GFS.

The GFS is letting the low pressure system slide down a bit farther south than previously thought, enhancing the precip abilities farther away from the GL and closer to the Kentucky Tennessee areas. Despite this, relative humidity will remain very high throughout Chicago into maybe St. Louis.
Thickness would be fine in the GL and even a bit south.

The CMC would rather hoist the low up through south Illinois and into Indiana, bringing substantial precip through the lower GL and mainly across the entire East CONUS. (The US.)
RH will be abundant throughout this area.
Thickness shows that the precip would eventually change to snow with significant accumulations possible.

The NOGAPS wants this low to take the same track as the CMC, but bring up precip farther through the GL. Thickness for the Lower West GL would be adequate.

Total Accumulation Ensembles----
So, for 12 total precip ensembles:
6 members show the storm mainly striking the Mid-South east in Kentucky Tennessee areas.
4 members show the storm striking the Lower GL.
The other members show the storm not strong enough to make significant precip.
Out of that, I think that it's a tossup between the more western track and the southern track.

The meteogram shows snow definitely occurring.

The below is a quote from weather.com
Midwest: Snow moves out of the Missouri Valley and Upper Midwest, intensifying into heavy, wind-driven snow in either the western Great Lakes or mid-Mississippi/Ohio Valleys Saturday night, continuing into Sunday, depending on the exact track of the surface low. A period of sleet or freezing rain also possible in the Ohio Valley Saturday. Major travel disruption seems likely!

Northeast: Precipitation may start as either snow, sleet or freezing rain Saturday night into early Sunday, mainly inland of I-95. Some icing is possible from western VA into Upstate New York and northern New England. That said, a changeover to rain is expected, particularly near the coast Sunday. However, locations from western New York through the Appalachians may quickly change back to heavy, wind-driven snow later Sunday through early next week. Majortravel disruption possible!

Southeast: Severe weather threat looks limited, due to a lack of warm, moist air penetrating northward from the Gulf of Mexico. Some t-storms may bear watching near the Gulf Coast Saturday, then again late Saturday night into Sunday from the Carolina coast into Florida. More snow is expected for the Smoky Mountains and also possibly parts of Tennessee and Kentucky Sunday into perhaps Monday.

Significant East US Snowstorm on the way.

I now have enough confidence to believe that this storm will take shape. I just ran the newest models.

Well, the ensembles showed the thickness line staying below the Chicago, Madison, Quad Cities area for precip, but affecting the Chicago Milwaukee area more than the other Midwest cities.

The precip featured is forecast to be heavy.
But I want to put an emphasis on how hard the areas such as Kentucky may be hit.
The colors on the ensembles are green and yellow. I haven't seen that on an ensemble before.
I encourage that area to prepare for a blasting of rain.

So, in summary, Chicago and Milwaukee should prepare for disrupting snow, while Kentucky and Tennessee areas should prepare for a blasting of rain.


The CMC shows the thickness line too close for comfort as the system barrels through. However, then the thickness will fall and change to heavy snow. RH will be sustained.

The GFS indicates that the low will dive much farther south and barely affect the GL areas. But it will be a monster when it impacts the Southern area in that time period, IF it affects them.

The NOGAPS indicates the thickness line extremely close to Chicago. But then changing to Snow.

Updates later.