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Wednesday, August 22, 2012

Isaac vs. Irene

What are the chances that here we are again in late August with an "I" named storm that is in almost the same exact position that Irene was in only one year ago? Not only that, but we are seeing the same exact strength and model trends with this storm that we saw with Irene. It's really incredible. Now does that mean that Isaac is bound to make its way up the east coast like Irene did? Not necessarily, but it is a major leading factor in why I believe the storm will end up further northeast than currently shown on models... Let's take a look!
Yesterday afternoon.Irene (left) and Isaac (Right).
It's the same models doing the same things. We see them bring the storm to the south and weaker because at the time the storm is weaker itself. Then we see the storm develop and we slowly see a trend to the north and east... Exactly what we're currently dealing with for Isaac. Check out the video above. Shows all the latest trends and thoughts on Irene last year. If you watch the whole video it's amazing to see meteorologists actually thinking Irene was heading into FL or the Gulf... Very similar to what is going on now.
The shift in models are already beginning. You can just tell from tonights 00z's, we don't even have any of the models taking the storm into the GOM so far... That's a significant shift. The 00z GFS follows this trend, taking the storm just inland and scraping the entire east coast.
You're looking at the main reasons the models do this shifting... Storm strength. Look how organized and strong Isaac is looking already. Strong storm = greater rise in latitude.
Donna 1960
Bertha 1996
Floyd 1999 Possible analogs for the storm are posted above. Do not pay attention to the exact strength... Just the tracks. Of the 3, I think Donna is a very interesting one and for now the most likely. I think a combination of all 3 though works best.
Last but not least, my latest map. An updated one will be coming out tomorrow morning, but my current one still agrees with my latest thoughts. Sorry the blog was thrown together so quickly! More updates to come tomorrow and over the next week as we track a potentially devastating hurricane heading towards the United States! -Scott P.

Friday, April 20, 2012

Nor'easter breakdown

Good evening folks! Around 5:00 PM here in southern California with a thick fog rolling into the area. I've been blessed by the weather gods over the past few days, as the area has seen nothing but sunshine and warm temperatures. Good news is I get to wrap up my Spring break here tomorrow, and then I'm heading back to southwestern Connecticut just in time for the big nor'easter... The question is though, will I be able to land? Not sure how easy landing at JFK will be on Sunday afternoon, but we shall see! Enough about myself though, let's talk about this "monster"! I've been monitoring this thing for just about a week now, and my overall views on the storm haven't changed too much despite the usual model mayhem. I try to tell people, do not ride the model train... It's not a fun ride! We have seen everything from models just 24 hours ago show no storm, to models who have stayed consistent for the past week. If I had the power, I would come up with a super model that would nail this thing off the bat... But that wouldn't be as much fun, would it? Luckily things turned for the better late last night, as we saw the GFS and NAM join the solutions that the other models were seeing. So let's break down the latest from the models. 12z European model:
12z GFS model:
12z NAM model:
12z NOGAPS model:
12z Canadian model:
12z JMA model:
12z SREF model:
As you can see above, I have selected 7 different models to show you. The European model (top) is rather interesting as it has shown a massive storm for more than 3 days now, and then this afternoon it backed off of that idea. Now rather than showing a sub 990 mb low pressure system with a tight wind gradient, we see more of a loose and weaker storm. No doubt its still big and nasty, just not nearly as strong as it was once shown. This is one of several reasons why this particular run should be taken lightly. We watch for consistency, and once we see that consistency broken, we need to wait for more runs to come in so that the model can regain consistency. Same can be said generally about the GFS. We watched it show no storm for a very long time, and then late last night it jumped right in with a powerhouse nor'easter... only to loose it this afternoon. While there is still clearly a well defined nor'easter, it is no longer the strength it used to be. Exactly why I remain cautious about drawing the conclusion that we are going to have a weaker system. The GFS also has been trying to fiddle with a double barrel low pressure system; something that other models have not shown. To me that means that not only is there a struggle for consistency, but with agreement as well. This also applies to the other American model, the NAM, which earlier had a sub 980 mb low pressure system, and has now clearly backed off. So there are some REALLY interesting an important notes that we can take away from just those three models. We are seeing a jump away from this "monster storm" all of a sudden, which is why I caution people to say this will be the final solution. We are still more than 60 hours away from the storm, and as I have said, models like to fiddle around. But then again... Isn't it interesting to see they all jumped to weaker solutions? Another note to take into account. The good news for now is, we are seeing FAIR model agreement. Like I have said though, nothing is set in stone, and the 00z runs tonight will be crucial in determining a more definite track for the system. So what's the biggest concerns with the system, and for who? No better place to start than with the rain!
Here's the 12z NAM, which is one of the more widespread with the rainfall. A large area of 2-3 inch rainfall amounts, with bands and strips of 3-5 inches of rain. That spells out flooding right there, especially because a lot of this will come down very quickly.
The similarities between the NAM rainfall and the CMC rainfall are remarkable, as they essentially put down the same amount of rain in the same areas. True model agreement, which is why I prefer these models right now for the moisture. In the end though, it will all have to do with the storm positioning.
In a typical nor'easter, the heaviest rains and winds will be to the north and east of the storms center, so it will all depend on where the exact track of the storm system is. It is clearing visible from the NAM and CMC above that the track is to the west of where you see 2 and 3+ inch rain amounts. Above is the April 2007 Nor'easter, which may in fact be a decent analog for this storm system. Winds are another matter, and while they don't look to be the biggest concern with this nor'easter, they remain a threat. Along the immediate coast from NJ to ME, winds should be sustained at 25-40 mph, with gusts possibly up around 50 or 55 mph. That is if the models continue to show what they show currently. If they begin showing a tighter gradient, those numbers may be bumped up 5 to 10 mph, but if they continue showing a weakening trend, we do the opposite.
I'll leave you all with this. I don't exactly buy into this whole, 6+ inch widespread snowfall amounts. But elevation snow of 4-6+ inches is not out of the question, as it has happened before... and if everything goes right, I don't see why it cannot happen again. If you are in a valley or lower elevation of western PA or NY, I think a change over to wet snow is possible. However, it will only amount to a few inches. That is significant though! Something that I believe people have to begin realizing. A few inches of snow with trees covered in full bloom could lead to disastrous conditions. This may be the most dangerous aspect of this storm system, so I will continue to monitor it and fill you all in with detail.
I've decided an updated map before the 00z runs wouldn't be smart, so here is the one I created this morning. Obviously there have been some changes, but I do not want to do anything just yet since there will be more to come... so for now, enjoy! General thoughts remain the same, so do not think you are being mislead. Keep following me on Facebook and remember to follow me on my twitter as well which can be found on my Facebook page! Should be a very interesting next 48 hours, so stay with Wild about Weather for all the latest! -Scott Pecoriello

Thursday, January 26, 2012

A 2011-2012 Winter update

All hope is lost on winter. No snow, all warmth. Spring right around the corner. 2011-2012 to be remember as the year without a winter... Right? Wrong. The forecast I released in the middle of January has succeeded so far, and I still stand by it 100%. Will it end up being 100% right in the end? Highly unlikely. But is it possible that I get the general idea of a colder and snowier month ahead right? Certainly. What is bothering everyone are these amateurs, and professionals, already throwing in their so called "towel". Why? They're sick and tired of this pattern... And I am as well! That doesn't mean we shouldn't continue to look for snow opportunities in the future though, or jump off a cliff and give up on the entire winter season. Patterns change! And while we've had a number of false alarms already this season, and people are absolutely sick of them (As am I) that doesn't automatically mean this is the season of false alarms and opportunities. The truth is, we cannot say the upcoming month will be full of cold and snow nor can we say it will be full of more warm and wet weather. What we can do though, is look at all of our variables driving the pattern, check all of our models, check all of the long range signals, see what has and hasn't worked so far this winter season, look at other forecasts and reasonings, and come to a realistic and reasonable outlook for the rest of the 2011-2012 winter season. Before I go on though, you should know I am not a "wishcaster", nor am I "wishcasting". I am being realistic, and giving you my forecast. With that said, this is my first winter season actually doing forecasting for a public audience of nearly 1,000 people. That is why I am glad the winter has so far (with the exception of the end of January) been a bust for me. This will only help me, and many others, grow as a meteorologist. Now with that said, let's get started...

January 26th. That is the date that stands on the calendar. Winter season ending, right? No! That is one of the number one issues here. People are stuck on this calendar. I'll tell you, the date and time of the season is very important, but only if you actually know the significance behind the date and truly know where we are! Too many people don't. The halfway mark of winter, on this calendar that everyone obsesses over, is right around February 7th. That's right! We're not even halfway there, and people already have their mind set towards spring. This whole sun angle nonsense, and not being able to get snow as we get into February could not be further from the truth (Just finished a semester in Astronomy, trust me, I know). Yes, the sun angle becomes an issue as we get into late March, but that doesn't mean it can't snow. It just means it doesn't stay around as long. So what exactly can we expect as we head into February and why? Let's look at... Everything!

Oh the absolutely lovely teleconnections. The king of our false alarms this winter season. Will they ever prove themselves correct, or bring us the cold and snowy weather? Take a look...

I guess we should start off with the most important and influential of them all. The Northern Atlantic Oscillation. I'll start off by saying, tomorrow there is a good chance this graph will look nothing like it does now. The NAO changes, and changes and changes. Only trust it in it's short range! Lesson learned! So if we focus on that, the gist of this is, it is going downwards. Dropping. In fact, it's probably going to briefly dip negative. Maybe even for a slightly extended period of time. After that though, its up in the air again. I don't even want to look at it, so stop yourselves now. Overall, I am pleased with the NAO. Looks more conductive then it has in the past for colder and snowier weather.

You can say this particular teleconnection has been on my list of favorites over the past several days. The Arctic Oscillation. Negative! We just need to keep it that way! Well that looks safe for at least the next week, and remember, we don't look past a few days on these teleconnections. Only thing that I am thinking while looking at this is, it's negative. Again, conductive for colder and snowier weather

Last but not least... My new favorite? I guess you can say that, considering looking at where it is going. Positive. The models are very consistent now with a very positive PNA. This is going to help with the colder and snowier weather is well.

So I want to take the teleconnections and put a big old check next to them in terms of conductivity for colder and snowier weather.

The force partially responsible for driving our teleconnections, and further determining what kind of storms we may be seeing, is our MJO. So lets take a quick look.

A lot of interesting things to note about our MJO above. One, look where it has been in the past. Hanging around phases 4, 5, 6, and the COD. Tisk, Tisk. That is very un conductive for a wintry set up here in the Northeast. Now take a look at where it currently is. Phase 5. Again, very un conductive for cold and snowy weather here in the Northeast. Now, take a look at where it's going. The GFS ensembles seem to want to take it into phases 6, and then 7. Not a bad place to be, and definitely a better place then what we have seen. The question is now, will it verify? If it does... The snow lovers may just be howling. But that's a big IF right now. Watch it carefully.

Ok, now I'm not "obsessing" over this run of the GFS because it proves my point, and gives us a load of snow. I'm looking at it, analyzing it, and seeing if it makes sense or not and why.

Yes, I am totally and completely aware this is the Long Range, 18z GFS models. Some of the worst weather accuracy. But for observing the teleconnections, and where the MJO may be heading, these solutions actually aren't insane. A diving NAO, a -AO, a +PNA, and an MJO potentially heading into Phase 7. That usually screams an east coast snowstorm. But, take this as a grain of salt. This will change, I promise. The question is, how much, and what will be the trends. I will focus on that in the coming days, but for now, it remains a sure mystery.

Now onto some of my own forecasting! Time to review my mid January outlook for the second half of January through February. For the most part... Success! Here it is again below.

So, let's hope for more success in the future, but as you can see, the general forecast has been on target. From everything with the above normal temperatures and warming, to the snowstorm we had last weekend. If the forecast continues to be on track, you can expect that colder and snowier February we've been talking about... I know some of you are crossing your fingers!

But just like to every story (including winter stories) there are two sides. So now for the dreaded moment. The warm side.

We'll start with our SOI values. Tisk, tisk, they're shooting up. Fast. This generally means warmer weather, so it's not what we want to see exactly.

Another long range look that goes against a cold and snowy February, include some of our climate models and very long range models. Here's a quick glance at a very long range model that runs off of our European model. That's nearly 60 degree temperatures around NYC during the middle of February... Ouch.

I feel it's appropriate to end with our "False Alarms" because that is what has been getting to people. Here's just a few of them.

False Alarm #1

False Alarm #2

False Alarm #3

For those who have been following these lovely teleconnections... You know there are more examples...

So what to say now? It's a battle. A big one. And it will be very interesting to see who wins. There are plenty of variables pointing to the second half of Winter 2011-2012 being very cold and snowy, and variable pointing to the exact opposite! Enjoy your evening, and try not to let your head hurt with all of this! More updates in the coming days, so be sure to stay tuned to "Wild about Weather"!

-Scott P.

Friday, January 13, 2012

Throwing in the towel on winter... Am I the only one left?

It's been a bleak past few days in the Northeastern United States. This is mainly due to the recent outburst from both professional and amateur meteorologists, that there will be no winter. Am I the only one left not "throwing in the towel" on this winter season? Am I considering "throwing in the towel"? All these question will be addressed in the blog tonight, and much more, so lets begin.

Believe it or not, this winter is already off to an historic start. There has never been a recorded winter where New York City has not seen accumulating snow in November, December, and January. It is January 13th, so we have roughly two weeks left of January. Will New York City set a record? It's possible, but not likely. Taking a glance at all the models over the past several days, there is support for at least one or two smaller systems to affect the New York City before the month of January goes out. Now whether this is an inch of snow or 5 inches of snow, will remain a mystery for a long time, but I'll keep an eye on the dates between 18th and the 22nd. That's when I see the possibility of a clipper system, they may end up even being a miller B. But again, this is mostly speculation at this point.

Here's what the clipper system looks like on the 18z GEFS ensembles

So what does the rest of the winter season hold? Well the easiest way to answer that is... It remains a mystery! But of course, I won't leave you guys hanging there! I am not throwing in the towel on this winter, nor do I plan to. Yes, so far this winter has not gone the way I had planned, and not the way most planned, but that does not mean we are all screwed for the rest of the season. We have more than 60 days left of this winter season, and we have been stuck in this crappy pattern for months now. Although it has altered slightly at times, it remains the same overall pattern. Horrid. The NAO has remained steadily positive, for the most part, for months now. This is almost unheard of. So just historically speaking, you can see a pattern change to colder and snowier weather is already in support.

Just a glance over our current teleconnections helping to drive our pattern.

Interesting. The NAO is actually negative! Something we haven't seen in a while, and might help to explain why it is going to be so cold this weekend. But look where it goes next. Another bump positive. Something we have seen since October and November. That helps explain the warmth coming during the second half of next week. And finally, long range says back towards negative... but when hasn't it showed that?

AO still looks good. Its going neutral or negative, and will support cold air. I have a feeling we see this change though give such consistent model guidance. Warm, warm, warm... and Warm! So, we'll have to watch this. Although, really the models usually catch onto the teleconnections, rather than the other way around, so we might want to watch what happens here with our AO.

And finally our PNA. Negative, and expected to stay that way. This will help drive the waves of warm into the east, and help to prevent sustained cold air. It is a battle between the teleconnections, which right now, don't seem to really agree.

But enough with this talk of a pattern change! I'm sure you're all done with it, as well as I. The change to colder and snowier weather will probably not be a dramatic one, rather it is a slow change. Once again though, I am done with pinpointing dates and times, and how's and whats... It's just not that simple. Now lets take a look what the expect for the next month!

Here's my extended winter weather outlook... Enjoy!

January 14th - 16th =

Lake effect snow slows down and very cold continues to take over the entire region. High pressure moves in as temperatures slowly moderate, but remain quiet.

January 16th - 18th =

A storm moves in from the west and spreads light to moderate rain showers along I-95 and the suburbs. Temperatures are above average as the storm moves in. Areas to the north of I-90 can expect some wintry precipitation, while areas to the south remain mostly rain, but may begin or end as wintry weather. The low pressure moves north, and temperatures plummet once again.

January 18th - 25th =

Very cold air takes over the Northeast region, as the area dries out once again. A potentially weak clipper system moves into the area north of I-80. Scattered snow showers and flurries take over, and may briefly turn moderate the further east you go. Temperatures moderate once again though after the clipper system moves by, and the region is back to well above normal temperatures. A wetter and warmer pattern takes over.


January 25th - 31st =

The warm and wet pattern continues for the region, with a better chance of wintry precipitation for the interior Northeast. Unlikely though. Watch the 29th-31st though. I do believe we have potential to see a good storm here. Whether it is rain or snow remains unclear, but I think we'll see in the coming days and weeks that timeframe is one to watch. Could be a snowstorm, as the pattern turns colder finally by the end of the month.

February 1st - 7th =

February may actually start off very wintry. The pattern (although I promised not to mention it) may actually truly break down here. Widespread cold across the entire county, as temperatures are well below normal. A line of storms looks to begin as well. Coastal storm after coastal storm moves up the east coast, potentially putting down widespread snowfall. The first one looks to come midweek.

February 7th - 14th =

Another coastal system may move up the EC during the beginning of the week. Temperatures are well below normal, as yet more system try and develop off the coast. More widespread snow is possible. The pattern continues into the third week, as cold and snow may be the theme finally.

So that's my current outlook. Folks, I have faith in February. Euro weeklies have already come out with a very cold and snowy pattern starting February 1st and lasting right through the 14th. Who know what happens after that. Again, historically this is supported as well.

Do not give up on the winter. For many, it has yet to begin, but it will... I have a strong belief that the folks throwing in the towel are going to be sorry they did. Remember, it only takes a period of less than one month to get snowfall above average, and winter to start up. One big daddy does it as well. No one can say for sure what will happen over the second half of winter, so stay tuned as we track it together. Have a good night!

-Scott P
Wild about Weather

Friday, January 6, 2012

Pattern change update

Not sure why people are so dull with our pattern change today. It looks as good as it ever has, in my opinion. NAO continues to be shown going neutral/negative, the AO continues to be shown going negative, and the PNA continues to trend away from going negative, and looks more neutral now. Either way, the PNA isn't concerning me because our AK vortex is moving out of AK and into Canada (Not sure exactly where yet) and our EPO and WPO will go negative, only increasing the cold air in our country. The MJO is now in the COD, which will help keep it away from interfering with our pattern for the most part. From there, it looks like it spins around in octant 6, 7, and the COD, which are fairly OK places to be. Big system comes around on the 12th-15th of January, just as all these variables go favorable... That spells a pattern changing system to me. Yes, it will be rain, but that was expected. The question is, what exactly happens after that system... Cold and snow?

-Scott Pecoriello

Tuesday, January 3, 2012

Winter finally in sight? Pattern change to start us off?

Definitely an interesting couple of days we've had, and it finally looks like a lot of our variables driving this horrible weather pattern will begin to shift in the right direction for a pattern change. When exactly do we get this pattern change is still up in the air at this point, but a time period is more clear at this time. Tonight I will go over why we are seeing the pattern begin to flip, what we can expect from the pattern flip, and timing for when we see a start and even an end. Let's get started!

Our "terrible teleconnections" seem like they're maybe trying to redeem themselves. Take a look here at the teleconnections from the Climate Prediction Center. Looking fairly good for a pattern change.

So here's the gist of it. The NAO is going neutral or negative, the AO is going negative, and the PNA is going negative. NAO and AO are a check, but the PNA not so much. The -PNA will help drive the cold into the west rather than the east. Not worry though folks, looks like a -EPO may save us. The -EPO will help drive even colder air into the country. While not as much of a help, we will also have a -WPO; just further helping with the cold air! All of this may end up giving us a gradient pattern here in the Northeast. What's that? I-80 on northward will do well with the cold and snow, while south of there will struggle. Will this necessarily be the case? No. But is there a good chance? At this point, I'll say yes. All the negative teleconnections usually point towards a gradient pattern, so therefore things are looking good for that right now.

Look at the next 10-13 days. EPO goes negative.

Look at the next 10-30 days. WPO goes negative.

The only thing that might throw all of this off a bit is our -NAO. For once, this will be a good "throw off" for the snow lovers. The potential blocking may make for bigger storms, and therefore give much less of a gradient pattern. I still can't guarantee that areas south of I-80 will benefit from the blocking pattern still, but a much better chance. Our -AO and -EPO will really help to drive the cold air into the Northeast.... For the most part it should cover up the -PNA.

Hopefully all of you now get the idea that our teleconnections are really pulling through for us, and this is the happiest I have been with them in a while. Mostly because of our NAO! Finally looks to go negative! Who to thank? Yes, you knew this was coming. SSW.

The stratosphere is really warming up folks, and while it has been for a while, it is important to know that now we have the warmth spreading into more layers of our atmosphere (specifically further down in the atmosphere). Rapid warming at that. This is likely why we're seeing a lot of things heading into a more favorable direction for a pattern change.

Looks what's beginning to happen folks...

Before we get started on the details of this change in the pattern, let me clear my mind for everyone. I am not sold on this pattern change yet. Why? The models have yet to really catch on. We've certainly seen a shift to colder long range weather from them, but it is not yet good enough for me to hop on the snow train yet. I expect that to change in the coming days though. All of these variable should be picked up by the models soon enough.

Now to what you can expect from this change. Not a lot of detail on that unfortunately. Again, typically when we see the variables like they currently are, a gradient pattern is possible. So, small to moderate snow events I-80 on northward, with a "rip off" to the south. But again, this blocking may be good news. Larger storms that can ride up the coast with heavy snow and strong winds; a classic nor'easter. It's just a matter of getting the cold air or not, which I can't see why we don't with such a -AO coming up and a -EPO. The point I'm trying to make here, is colder and snowier weather for the Northeast looks to be on the way...

The harder question perhaps is when... I'm going to take a shot (like I have many times already this winter!) and say between January 10th and January 16th for a pattern change. A wide range? Maybe, but the point is the middle of January looks to be a good time range. Will it be a dramatic change in pattern? Not really, but certainly noticeable if we get the snow going.

Just a quick look at one more thing before I go! The MJO!

A mess! GFS ensembles are looking very messy today! The story looks to be the MJO heads into the COD (not bad for the pattern change) and then back into octet 6 (also not bad for the pattern change). From there it looks to settle in that area for a while. Hopefully, though, we see it begin to go into a class counter-clockwise spin around, and we get it to go into octets 8, 1, and 2. Probably not for a while, but maybe later on in the winter!

REMEMBER FOLKS! We're not even into the second week of winter! Plenty to go, and good news ahead. Goodnight everyone!

-Scott P.

Saturday, December 31, 2011

The terrible teleconnections

Well, you can more or less thank the teleconnections for all the latest mild and rainy winter weather in the United States. The NAO has been positive, the AO has been positive, and the PNA has been positive. Where do you want these teleconnections for the cold and the snow in the Northeast? You want the NAO to be negative, the AO to be negative, and the PNA to be positive. So, the only teleconnection that has been cooperating, is the PNA. It's been solidly positive. Well... A flip is about to take place... It's one that makes me happy and upset.

The latest teleconnections (which I cannot post because I'm on vacation time!) look interesting. FINALLY we see the NAO go towards neutral or negative and the AO go towards neutral or negative! Good news, right?! Wrong. Normally I would be happy with this, BUT now we have to worry about the PNA. After having the PNA being the only one supporting snowy and cold weather in the Northeast, it too decides to go negative. Something that is not supportive of cold and snowy weather in the Northeast. So what happens now? Well we probably see blocking set up, and maybe even have some good storms set up along the east coast and Northeast, but I'm not sure we'll have support from the temperatures. If the AO really decides to go negative, I will be happier and then maybe the PNA won't be such a concern like it is right now for me. The AO usually supports very cold weather. But the negative PNA often is a signal for warmer weather, so it will be a battle between those two. We'll have to see who wins...

As for the MJO, I know people were starting to get excited about it going into octets 8, 1, and 2, but that no longer looks to be the case. There is still time for change, but right now I'm not very pleased with it. Rather then going into the correct octets, we see the MJO head into octet 6 (already partially in 6) and then briefly move into 7, before moving into the COD. Not a very good place to support a negative NAO. And after that? It goes right back into octet 4, and maybe even back into 5. But again, thats only if all of this verifies. There is still plenty of time for the MJO to shift about, maybe going into more favorable octets... Only time will tell though...

Right now we are at a state of battles between all these different variables. It will be very interesting to see which one of them will win out, and right now I really do not know. My hope is that we see the MJO do a flip in the COD and head back into octets 8, 1, 2, or even 3, OR we don't see it go into the COD at all, and it heads straight into 8, 1, 2, or 3. It would also be nice to see the PNA stay positive, but right now a lot of models agree we see it go negative. Trust me, I want the cold and snow as much as everyone reading this, but until I see things head more favorable for the cold and snowy weather, we need to continue watching and waiting. It will come sooner or later, it's just a matter of when!

-Scott Pecoriello