R.W.S Winter Storm Watch

As of 4 AM EST

R.W.S issues a Winter Storm Watch Effective 3/1/09 12 noon eastern standard time to 3/2/09 6 PM eastern standard time.

The following watch is in effect for Berks, Lehigh and Northampton Counties in Pennsylvania and for all of NNJ.

Low pressure developing over the southeast will continue to gather moisture from the Gulf Of mexico. While this is taking place, high pressure from the NW, will build into the region on Northwest winds. This will start to feed colder air into the region. Meanwhile the low in the southeast will start to head NE and proceed off the coast near South Central Carolina. From there the low pressure will take a northerly to NNE track up the eastern seaboard about 50-100 miles off the coast. There will be generous amounts of moisture with this low pressure as it rides up the east coast.
At this point and time it appears that a snowfall of 6 inches or greater can be expected. The ECM delivers .70 liquid QPF to this area and normal 10:1 ratios would be 7 inches. With ratios greater then 10:1 , the potential is there to receive up to a foot of snow.

Stay tuned to R.W.S for further statements/or warnings.

March Snow Storm Preliminary Call

Early March Storm Update

Let me us the 18 Z UKMET as an example here...


This is at 48 hours and this is the main reason I am not buying the NAM and the UKMET solutions tonight.

Now mind you i have been seeing this same set up for 84+ hours now on the models....

What you are looking at there is a strong arctic high to your NW.
An extension of that high to another high to the north in Canada that stretches into Southeastern Canada.
And then look to your east and you see another massive high pressure area.
Now notice how all three areas of high pressure are linked together.

They are literally showing a block..thats right i said block...

This low has no choice but to be closer to the coast because it can not escape off to the east very well. So..this storm is going to end up closer to the coast and that is the reason I have been so persistent on my thoughts.
Now if you notice with that type of scenario this is going to be a long lasting duration event..probably a sunday night into tuesday. Its coming from the gulf of mexico. So there is going to be abundant moisture...then once it hits the coastline it is going to tap in Atlantic Moisture. So we are going to be talking about copious amounts of moisture. Temperatures are going to be freezing or below freezing because of this NW arctic high that is pressing in. There will be a sharp cut off to the precipitation. I believe in PA it will look something like this....

Western PA=lighter snows
Central Pa = moderate snow
Eastern Pa = heavier snows.

Now that is not because i live in eastern PA but rather because this is a coastal low. So despite the deepness that this low obtains..its going to contain copious amounts of moisture. Ratios due to the cold will be greater then 10:1. Higher the further north...

I am not going to be bold enough to make predictions quite yet...but the potential is quite significant

February 22nd Clipper & Secondary Coastal

Alright after looking at the models and seeing what they are outputting the map below is based on the ensembles of the GFS and the NAM for the temperatures. Temperatures were not all that different between the NAM and the GFS.
So what is going on? Currently we have the primary precisely modeled to be where it was suppose to be. You can see this when looking at the pressure map. The primary though is slightly weaker then what it was modeled to be. Its in the range of 1008-1010. The GFS had it at 1007 at this point and the NAM had it at 1006. What happened before this storm headed towards the lakes is that the energy dug to the south quite far. This is relatively important that it allows the secondary to form further to the south.

Current thinking is the primary should weaken over time and begin to hand off to the secondary. Where does this secondary begin to form?

Its my opinion that this secondary low is going to form over Virginia. This secondary will then begin to move NE. The question that has to be answered is where does this secondary begin to bomb? Well that question can only be answered ONCE we see where the secondary begins to develop. We can use the models as guidance..but pretty many of us know that they are not gospel. So it will be important to check pressure falls and future pressure falls as these will give us a clue as to where the secondary is going to develop and also when....

Once this secondary develops it should start to deepen rather quickly. I am thinking right now this secondary will start to deepen once it goes off the coast around southern NJ. The temperature differences between land and water should cause rapid intensification..

With all the above said....here is my final map

Feb 21,22nd Clipper Snows

Its amazing to me how this storm looks so much like a carbon copy of this last system that came thru. Then again it should not be all that surprising because there really was not much space in between this last storm and the pattern that was in shape then. Not to mention the teleconnections when i went back and checked on them last night had not really changed all that much.

To get that big storm the models were showing a positive PNA. Problem lies in a positive PNA was never forecasted to occur according to CDC...
A positive PNA would have been a positive factor because it would have allowed a ridge on to the west coast and a trough on the east which would have enabled energy coming down from Canada to dig deeper into the base of the trough. That is not happening.
What I looked for next was the EPO. While it is true that we have a -EPO which will help to keep the SE ridge at bay, due to climate that factor by itself is not enough to depend on the cold air "pressing" behind the system to help carve out that trough. So instead of a + PNA trough on the east coast..we end up more with a -EPO trough which just does not allow enough digging for amplification of the system in question.

So what we have instead is a Clipper dropping down from Montana. This clipper will move ESE thru Iowa and then continue essentially along the same track this last storm just took. Kind of a wash, rinse, repeat. The winners once again this go around will be the State of Maine .

Feb 18-20 Snow & Rain Storm

We are approximately within 24 hrs of the event and the models seem to have a consensus on the track and precipitation types etc...
Low pressure currently over EC colorado should continue to track East before moving off to the ENE...

I am still not 100% convince that this low pressure will track to the great lakes as being shown on the models today as of 12 Z....

My thinking more or less is that we will track due east over northern ohio into NW PA and the ENE from there off the coast of Southern New England...

Unfortunately this track will cause a southerly flow ahead of the system. Lack of strong confluence and our 50/50 low never materializing in the right spot will cause the WAA to overspread the area resulting in precipitation breaking out sometime tomorrow morning. However..the steadier & heavier precipitation will move in in the afternoon....
Snowfall totals are explained on the map..In PA outside of the poconos that have the best chance of picking up 1-3 inches ..I would not count on much more then a T-1 inch.
Further north you go into the pink area ..3-6 inches could occur with the highest amounts inland, away from the coast..Along the coast more likely 1-3.
Further north from there into the blue area. This should be primarily snow with 6-12 inches possible. Even in these areas sleet may mix in.
I will continue to monitor the latest situation thru out the day and later tonight.

Flashbacks

Blizzard of 1996....
Why do I bring this particular storm up?

For starters it was the most significant snowstorm in this area since i can remember forecasting the weather. However..more importantly is how the models handled this Blizzard...
Taking a trip back down memory lane. The GFS first showed a Blizzard occurring along the east coast in its long range. As well as the ECM..However..both models essentially lost the storm. About a week out both models brought back the storm. With some differences. The GFS showed the storm missing the region to the south and the east and most of your local weather outlets bought into that solution hook line and sinker. I remember the day before WFMZ calling for snowshowers and flurries. Meanwhile the ECM brought back the storm and showed it as a crippling blizzard 7-8 days in advance. From that point on the ECM never lost the storm...
Flash forward to February of 2009. The GFS in the long range also showed a huge storm (snow) effecting the east coast into the northeast. The ECM also showed this storm as well. The GFS has now for the past 5-6 runs taken this storm off to the south and east and once again not effecting the region.
Meanwhile the ECM for its past several days of runs has showed a HECS or a Historical East Coast Snowstorm....

So as a forecaster of weather and you have people depending on you for your thoughts..which model do you choose to believe?
Well if history is repeating itself the ECM was the model to follow in 96 and the ECM will be the model to follow in 2009 of february.
So could we be dealing with a Historical East Coast snowstorm? ECM has consistently been saying yes we will. GFS is saying not a chance at this point and time.
The cards are laid on the table ..all that is left is too see how this is going to play out. Stay tuned for further information...

January Verification

Based on my map which was created 9 months ahead of time...this month seemed to work out quite well! I would have to grade this on an A + basis....