TORNADO WARNINGS TO TX, LA AND ARK NOW!!!

Thread: 932 mb Extratropical Monster Storm to Northeast !!! GFS 12z bombs out coastal low.1000 mb to 956 mb in 24hrs getting historical territory!!!

Ryan Maue‏@RyanMaue

GFS 12z shows foot of snow for E. Mass, Boston (?) as explosive low bombs offshore. Sunday snapshot [link to twitter.com]

Say what?? When, where??

Yes, when please?

where and when and how much snow?

i just see it, i was out all day... i think this crazy weather will start tomorrow, but let me chek it

AccuWeather.com‏@breakingweather

Jack Frost will make a brief visit to portions of the Florida Peninsula this weekend: [link to ow.ly]

15 hAccuWeather.com‏@breakingweather

Gulf Coast to Fla., temps could dip to lowest levels of season so far w/ potential for frost, freeze: [link to ow.ly]

Looked at the weather map on th blog site, Ct. is predicted to get hit on that map, everyone else shows us as a miss.

I am in south west Ct. no one else has us getting any snow for a while.

Thanks, I heard Boston the Cape and Maine not southern or western New England.

Saturday, February 16, 2013February 21-23 High-Impact Potential Significant Winter Storm (Posted 2/16)
By Andrew at 2:11 PM
Storm title is kept the same despite crucial model differences. I do this because, despite said model differences, it is quite obvious that someone will get a thumping of snow out of this storm system. The question right now is: Who?

Satellite imagery indicates that our storm system is moving into the Gulf of Alaska at this hour, with elevated levels of infrared imagery suggesting the center of this storm system is located around the Aleutian Islands. Pressure observation charts suggest the storm system has a minimum pressure of 988 millibars, a pretty solid storm system. The comma shape of the infrared imagery depicts the storm as a well-functioning system that will certainly be able to make some noise on land, both on the wintry side and the severe weather side.

This continues to be an unresolved issue between the European model and several other reputed models. Shown above is the Day 5 forecast for 500 millibar height anomalies. Cold colors indicate low pressure systems, while warm colors display high pressure areas. We see our storm system in the Southern Plains at this time, with high pressure in the East US and additional high pressure near Greenland. This high pressure system in the East US is what is causing such intense model differences. Both the European suite and American model suite agree that the storm will be ejecting from the Rockies in the position shown above in the apricot color. That's where the similarities stop. The European model believes high pressure in the East will force the storm system to move north-northeast, cutting out many regions of the Midwest from snow that was previously shown by this model.

These are the American ensembles for the same timeframe and same parameters as the European image above. We still see our storm system in the Southern Plains, although there is no longer an apricot shade. This is to be expected, as the ensemble members begin to diverge at this stage and therefore the mean solution is not as strong as the single European model. In comparison, the high pressure in the East US is weaker and centered further north in Canada than the European model has it. This is a crucial difference, as the weakness of the high pressure does not force such a northward movement anymore. It does move northeast, but nearly as drastically as the European model. Also of interest is stronger high pressure in the Pacific than in the European model. This stronger high pressure would force the storm further south.

I'm having trouble understanding why the European model takes the storm directly into the high pressure system. It is apparent that we will see some northward movement in response to persistent low pressure anomalies in the West and high pressure anomalies in the Northeast Pacific. These two factors make up the negative Pacific North American index (PNA). The negative stage of the PNA responds to the low pressure anomalies in the West by provoking high pressure in the Southeast US, and this does correlate with the issue the models are having with the high pressure in the East US. If it was just the negative PNA, we would most definitely see the solution being shown by the European model. However, we now go back to the previously-mentioned high pressure over Greenland. When high pressure is established to the east of Greenland, it is called and East-based Negative NAO; 'East based' for being east of Greenland, and the negative NAO (North Atlantic Oscillation) implies high pressure over Greenland. The negative NAO provokes the subtropical jet stream to become more active and pushes the overall storm track south. It also suppresses the high pressure in the Southeast, which is why I'm not confident in the north-bound European model. Both images above show the east-based negative NAO, but both have different solutions. It all comes down to which factor has the stronger influence. Because the negative PNA is upstream of the Midwest, it will have a stronger effect than the negative NAO, which is far up in Greenland. However, by the time the storm system is able to reach the Plains, the negative NAO will hold some influence and ought to be able to keep the storm system south, definitely further south than the European model's solution.

It's times like these when you have to stop looking at the models and think about how the atmosphere works. In times like these, I like to use my aforementioned river analogy. If this storm was a leaf that had fallen off a tree and into a river, would it want to move towards the rock in the river or towards the open river channel? If you think it wants to move towards the open channel, you've just explained the big paragraph I typed above. And in all honesty, the models are worthless. Until the storm gets on land, we might as well be trying to throw a dart, in the dark, blindfolded, spun around several times, with the correct solution being the dartboard bullseye three millimeters wide and a mile away from you. But if you're going to look for hints, always look at the ensembles. They stand the best shot of being right from a time this far away, which is another part of the reason why I support the cross-country solution.

The 12z run of the American model shows very heavy snow in the Plains. I am very confident that Nebraska and Iowa will certainly cash in on heavy snowfall. Even South Dakota could receive some extreme snowfall. Amounts could very well exceed 18 inches based on snow-to-water ratios above the usual 10:1 (10 inches of snow equals 1 inch of water). We could see ratios flirting with 20:1, meaning there would be lighter, fluffier snow, but a lot more of it. Towards the Midwest is where confidence drops. The American model believes in a sharp cutoff near Chicago. A sharp cutoff will happen, but this is the first time the American model proposes a cutoff zone so far north. The American ensemble system has been more persistent in the rain/snow line remaining in central Illinois. This is the same solution previously shown by the American model, up until now.

As of now, the European model is a far north outlier, and the American ensembles have been very consistent. I preferred the American ensemble solution, because I don't buy into an extreme far north solution. To me, there are three stages of the models. The first is the Long Range track, where the models get a consensus roughly 10 days away from the event. The second stage is what I like to call the '60 Hours of Chaos', where the storm gets within 8 to 5 days away (Hours 180-120 on the models) and the models go in every which way. The third and final stage is the final track, where the models converge on a solution within 5 days of the storm. This final track can sometimes be nearly the same as the first Long Range track. We already observed the first stage, and are now clearly in the second stage. The system will get on land in the next few days, so model solutions should clear up as the time comes closer.

I will update daily here on the blog, and much more often on our facebook page at www.facebook.com/TheWeatherCentre .

Andrew [link to theweathercentre.blogspot.de]

February 21-23 High Impact Potential Significant Winter Storm
By Andrew at 4:50 PM
Have downgraded system from Blizzard to Significant winter storm on account of recent model trends. Will maintain rest of storm title.

Infrared satellite imagery of the Pacific Ocean shows the storm of interest near the Aleutian Islands. We can see some convective activity associated with the front end of the storm system, characterized by a nearly vertical line of elevated infrared values. The storm itself remains far out to sea, away from any nearby weather stations in the Mainland that would otherwise help figure out model forecasts. We will need to wait until Tuesday or Wednesday for this system to crash ashore and the National Weather Service's weather balloons to get inside the storm and help out model forecasts.

Previous model agreement has been wiped away as we enter the dreaded timeframe where the models go every possible solution before they convene on one solution. This process typically takes a few days, but can last more than 5 days. I expect we will see model agreement come Wednesday evening when the system gets onshore. Model disagreement appears to be stemming from the forecasted strength in high pressure that will be over Canada and into the East US when the storm digs into the Southwest. When this storm system hits the West Coast and shifts south, it is typical to see high pressure arise in the East. The big question is, how strong will this high pressure be? A stronger high pressure would result in a more northerly track, while a weaker ridge would indicate a more cross-country, west-to-east storm track. This cross country idea is what earlier model solutions were showing. This dilemma is shown on the 500 millibar forecast from the American ensemble prediction system above. Our storm system is shown in the West US, with high pressure in the East. In this situation, the base of the high pressure system is in Canada, so the storm takes a more cross-country track. The actual American model has the base of the high pressure system in the Great Lakes, which is how we get that north track, as shown below:

My thinking is that this storm is going to hit areas that the models were in good agreement yesterday. The reason? Well, let's go in order here. First, we'll start in the West US. We have low pressure in the area, and that can instigate high pressure response in the Southeast US, which would go hand in hand with the American model solution above. However, looking at Greenland in the upper part of both images, we see high pressure to the east of Greenland. This is what's known as an east-based negative NAO. You can probably figure out why it's named east-based, but the negative NAO infers high pressure is in place in Greenland. This high pressure can then force the subtropical jet stream (located along the South US) to act up, and this brings the storm track further south. Also, it can oppress formation of the Southeast Ridge that the West Coast low pressure is trying to do. These two indices that are battling for the Southeast may just cancel out and we could see that cross-country solution as I suggested. The third (and probably most important) reason is that storms don't head right into high pressure systems. Don't get me wrong here, they can, but in a river, does water try to go to the place where it will get stuck? No, it goes towards the most open part of the river to keep on moving. This means that the low pressure system would theoretically not want to go north, right into the Canadian high pressure system. Rather, it would want to travel west-to-east (cross-country track), where it would encounter less high pressure anomalies. Adding onto that, if we see the base of this high pressure will be in Canada, the weaker high pressure anomalies in the Southeast would not be able to properly force the storm system north, like recent model solutions have been showing.

It's times like these when you have to stop looking at the models and think about how the atmosphere works. In times like these, I like to use my aforementioned river analogy. If this storm was a leaf that had fallen off a tree and into a river, would it want to move towards the rock in the river or towards the open river channel? If you think it wants to move towards the open channel, you've just explained the big paragraph I typed above. And in all honesty, the models are worthless. Until the storm gets on land, we might as well be trying to throw a dart, in the dark, blindfolded, spun around several times, with the correct solution being the dartboard bullseye three millimeters wide and a mile away from you. But if you're going to look for hints, always look at the ensembles. They stand the best shot of being right from a time this far away, which is another part of the reason why I support the cross-country solution.

I maintain the high impact part of the storm title because I do believe that there will be an intense snowstorm somewhere with the storm. The system in question will tap into pure Gulf of Mexico moisture that will allow heavy snow to fall across a potentially wide swath of land. Right now, a North Platte, NE to Cedar Rapids, IA swath is looking good for the most snow, with similar amounts east until Gary, IN.

There will be more developments as we progress through the weekend and into next week. My thoughts will undoubtedly change, but that's what weather does: change. Please don't ask for your location's snow, I will not answer if you ask.

Andrew [link to theweathercentre.blogspot.de]

NWS New York NY‏@NWSNewYorkNY

Wind advisory for #NYC metro, LI, coastal CT, south Westchester. 10 am SUN-12am MON. Gusts to 50 MPH [link to ow.ly] #nywx #njwx #ctwx

5 minNWS New York NY‏@NWSNewYorkNY

Winter weather advisory for eastern Suffolk LI, & south Middlesex & New London CT. 3 to 5 inches possible. [link to ow.ly] #nywx #ctwx

Thanks !!

AccuWeather.com‏@breakingweather

Band of snow approaching Charlotte could drop a quick 1-2 inches in the next few hours. [link to ow.ly]

Here's radar of what's going on currently if anyone's interested. [link to www.intellicast.com]

NWS Raleigh Discussion...

...THAT TURNS OUR FOCUS DOWNSTREAM ACROSS UPSTATE SOUTH CAROLINA...TO WHAT WE THOUGHT WOULD BE THE PROVERBIAL "WILDCARD" WITH THIS WINTER EVENT. OVER THE PAST COUPLE OF HOURS...CONVECTION HAS DEVELOPED NEAR GREENVILLE-SPARTANBURG(PRODUCED 2 INCHES OF SNOW)...ALONG THE TILTING CUSP OF THE POTENT VORTMAX AND UNDERNEATH TREMENDOUS COOLING/STEEPING LAPSE RATES ALOFT. RADAR AND SATELLITE IMAGERY IS IMPRESSIVE WITH A COMMA HEAD/BAROCLINIC LEAF EMERGING...WITH A GOOD LIKELIHOOD THAT THIS FEATURE/CONVECTION WILL GET BETTER/STRONGER AS
THE UPPER PV ANOMALY CONTINUES TO EXTEND DOWN INTO THE MIDDLE TROPOSPHERE.

THIS AREA WILL HAVE TO BE MONITORED OVER THE NEXT 6 TO 9 HOURS AS IT PIVOTS EASTWARD WITH THE POTENTIAL TO PRODUCE A CONCENTRATED AREA OF HEAVY SNOW...AND POSSIBLY SOME THUNDER SNOW(EARTH NETWORK LIGHTNING DETECTION SYSTEM HAS DETECTED ONLY ONE LIGHTNING STRIKE AT THIS TIME BUT AN UPTICK IS QUITE POSSIBLE)!

Right now there is snow/rain covering the entire east coast minus florida. And into Canada

yes and snowing hard right now at Carolina Raptor Center near Charlotte

[link to images.intellicast.com]

[link to images.intellicast.com] [link to images.intellicast.com]

just looked at the 10 day for Florida..no freezing temps or tornadoes mentioned anywhere, down to 35 tomorrow night, then backup to 70's and 80's throughout the week, no mention of tornadoes anywhere, what day are those suppose to hit??

In typical fashion, the Carolina Piedmont weather predictors hyped and overpredicted the first storm of the year and have completely missed the second storm with two inches (and growing) of snow sitting in my yard this afternoon.
Yes, only a couple inches, but significant around here. Best part is it will be gone by Monday morning.

the surface low is beginning to take shape..lets see what this puppy does when it hits the water [link to www.hpc.ncep.noaa.gov]

Had a little bit of snow earlier today, around 12:00 noon, here at the Jersey Shore. Currently about 45 degrees and overcast.

every local news in mass has said something different for snow totals, from a inch to 8 inches.

NWS Boston‏@NWSBoston

Extending the Winter Storm Warning for all of SE MA and RI. New Winter Weather Statement just issued.

The weather channel just said tomorrow's storm may cause more than the few inches for us, said any change in the storm could add significant snow fall here.

Here in Ct. too,

[link to radar.weather.gov]

More colorful map... careful there for those of you under alerts [link to forecast.weather.gov]