Can NJ & Eastern PA Make Up For Blizzard Bust?

BLOG SONG: "What Is Love" by Hadaway

Snow lovers across interior NJ and eastern PA are still talking about the "Roidzilla" blizzard that brought parts of southern New England and LI 2-3 feet of snow. The storm was originally forecasted by many to take a track close enough to the coast to bring snow to the aforementioned areas as well, but those forecasts did not work out probably because we threw all our chips into one basket. I can not speak for all the forecasters, but I can speak for myself when I say I was driven by what the EURO and its ensembles were showing for that storm instead of worrying about why the GFS/GGEM consistently kept taking the storm further east. An embarrassing case of "model hugging" on my part, but I'll cut myself some slack due to the complexity of the set-up and the lack of agreement between major models. It's over and done with and it's time to move on. 

The next threat is now February 1st-2nd (Sunday night into Monday)

The next system that could potentially bring significant snowfall to the area is scheduled for Sunday night into Monday. As you can see from the 12z EURO H5 Height Anomaly map, there is a -NAO to work with along with a -EPO and a neutral PNA. The Polar Vortex is over the Hudson Bay and in southeast Canada is a strong vortex which actually comes from the Clipper storm we're set to experience tonight into the morning. Notice the mid-level trough down streaming into the eastern CONUS bringing down an arctic air mass. 

The positive heights extending into Greenland in the prior graphic is a very nice west-based -NAO setting up. The EURO NAO index graphics clearly shows a -NAO by the time February 1st-2nd comes around. A -NAO in this case is going to do 3 key things: 

1. Slow down the northern stream jet. The northern jet has kept our pattern really progressive this year 
2. Allow the Friday Clipper storm to deepen and act as a secondary block, almost like a 50/50 low
3. Amplify the Monday mid-level trough and possibly bring it negative which would deepen a storm off the coast

12z GFS Model

The Clipper system may not bring much in the way of snow to the NYC Metro area tomorrow, but it is an important piece to the evolution of the Monday system. Once this clipper reaches New England, it is going to phase with some energy from the PV and undergo bombogenesis. This vortex will then sit over southeast Canada (#1) and act as a psuedo 50/50 low. The PV (#2) is located over Hudson Bay, far enough north to give the Monday storm space to track up the coast instead of sliding out to sea. The mid-level trough (#3) is already entering the Ohio Valley by early Monday morning and the northern stream energy looks fairly potent. 

By Monday afternoon, there is a sharp trough along the east coast  that has gone from neutral to negatively tilted (#1). This allows the storm to make a slight turn north up the coast instead of meandering out to sea. The confluence in east-central Canada (#2) is a big reason why this storm will not cut to our west, like models were originally showing. Instead, there may actually be additional phasing of northern stream energy into the trough which would strengthen the storm even more. That is not shown on any guidance right now, but it remains a possibility. 

12z EURO Model

The EURO model looks like a replica of the GFS. The energy at the base of the trough looks a little more potent which means the storm is stronger. But the way it handles the confluence to the north and how it positions the mid-level trough is almost identical to the GFS. 

While it is nice to be seeing this kind of agreement from major global models (the CMC looks like the EURO & GFS as well), there is still plenty of time for this to trend differently. There are 3 different storm tracks I am looking at. 

Blue: Rain and mixed precipitation into southern and coastal NJ but very heavy snow north of the baroclinic zone. The best snow usually falls just north of the temp. gradient as that is where there is the greatest frontogenesis, or lift. This solution could bring a Godzilla-type storm to NYC Metro. 

Green: The storm takes a track further south and mostly everyone is snowing. The baroclinic zone is pushed south but this also means ratios will be higher since we'll be in more of an arctic air mass thanks to the Clipper system that passes us tomorrow. Since it's a fast-moving system, this track will probably not bring as much snow to the NYC Metro area but it could still be a significant storm. 

Purple: This track would bring much less snow to the area, if any. In a case like this I would have to believe the PV squashes the storm or the northern stream energy never digs enough to amplify the mid-level trough. It remains a possibility as much as you do not want to hear that. 

We'll see which tracks ends up winning out come Sunday night. We should have an idea by Saturday. I will continue to update you all in the forum. 

Have a great weekend 

Frank 

visit and join forum @ www.njstrongweatherforum.com 

Blizzard of 2015 - Impacts & Timing

I want to start by saying a cyclone bringing at least 12 inches of snow is likely for the NYC Metro area. However, how extreme could this get? That is the question that remains un-answered this morning. The GFS model insists on a storm track further offshore and less potent, while the EURO is closer to the coast and very strong. That model in particular brings widespread 2 to as high as 3 foot snow amounts to certain areas. GFS bring about 1 foot. We're measuring snow in feet here, not inches, so that goes to show the magnitude of this storm. FIRST CALL SNOW MAP TO BE RELEASED AT 3PM ON www.njstrongweatherforum.com

Blizzard (green) and winter storm watches (blue) have been posted by the NWS for the Tri-State area. 

Timing

Start: 7-10pm Monday

End: 5-8pm Tuesday

A powerful storm is taking aim on the NYC Metro region Monday afternoon into most of the day Tuesday. Amazingly, this storm did not materialize on the models until late Friday. If you're a weather enthusiast you probably took notice of the 'potential' but the models were pretty adamant on keeping all the energy dis-organized and to our south. Our attention was focused on the Saturday system since for some people that brought them their largest snowfall of the season. Alas, here we are talking about a potentially Historic storm, which could bring some people their largest snowfall they've ever seen in their lifetime in 1 storm.

The EURO model has been consistent by continuing to show run after run of the same track, intensity, and overall set-up of the pattern in the upper levels.

The EURO by Monday morning is showing all the players involved on the field. Read the red text to get an understanding of what this means, but to the average reader, all you have to know is the set-up advertised on the EURO is one that would lead to a very potent storm off the coast of NJ. 

By Tuesday morning, we have one of the most impressive storms in history sitting off the coast of NJ pounding the area with blizzard conditions and burying us in snow. As the red text says, snowfall rates could be between 2 and as high as 5 inches PER HOUR. 

The worst of the storm comes between 2am-11am on Tuesday. A 984 mb storm sitting right on the 40/70 BM. 

You can get an idea of how temps. will look as the brunt of the storm moves in Tuesday morning. Air temps. are in the low to mid 20's, while 850mb temps sit between -7*C and -10*C. Temperatures this cold leads to higher snow accumulations of which we call higher snow ratios. Typically 1.00 inch of liquid would bring you 10 inches of snow (10:1). But we're expected to see 15:1 ratios for a period of time which will easily help snowfall pile up very quickly. 

Here's a look at the jet streaks at play here from the EURO. It shows an H25/125kt jet coming over the western ridge and phasing into the mean trough of the storm. This is one of the reasons why the EURO outputs an extreme solution. The dynamics at play would be crazy to look at! 

The wind gusts the EURO shows for LI are near hurricane force. 70+ mph in some instances. Winds are high enough along eastern NJ and NYC to warrant blizzard conditions. They'll be at their peak between 6-9am Tuesday morning. 

The GFS model seems to be struggling with how to handle the upper air vorticities. You'll notice on its latest run that it takes the main southern s/w energy and brings it toward the east side of the trough, instead of consolidating it at the base. Put simply, the phase between both branches was sloppy resulting in a storm system that deepens at a later time. It also does not hook toward the coast like foreign models suggest. 

So where are we headed? Is it Godzilla? Roidzilla? Frankzilla? These are questions that remain up in the air but I have a feeling by later today we'll have a much better idea. In my opinion, I think the EURO is not going to show such an extreme solution today at 12z. However, I think it will still look better than the latest GFS. Whatever the result it, a powerful storm is still going to impact the northeast. 12 inches of snow is not very typical, either. Stay tuned in the forum for the 1st call snow map. 

Next 3 Weeks Critical To Salvaging Winter

BLOG SONG: "Blame" by Calvin Harris

This is a 2-part blog. The 1st part will talk about the overall pattern in the medium to long range. The 2nd part will discuss individual storm systems over the next 10 days. 

Don't blame it on the night. Blame it on the NAO/QBO! 

Long Range Pattern

All winter long weather enthusiast's have been waiting for a pattern change, one that actually features snow when it's cold instead of dry conditions. There is no doubt this has been a very tough winter to digest so far given the high expectations most long range forecasters had in their outlooks. After taking a closer look of how the pattern evolved over the first month of the Meteorological winter, I decided to make an update to my winter outlook on January 1st. The update calls for average to below average snowfall and colder than normal temperatures. I specifically said in order to get at least an average season, certain variables will have to come to fruition and that is what I want to talk about today. 

The Stratosphere has been a big problem so far this winter. The QBO has been extremely negative due to mean zonal winds staying stubbornly westerly instead of reversing easterly like we typically see by mid-winter. There has been no SSWE (Sudden Stratospheric Warming Event) yet, but we have seen SSW at 10 hPa which has helped temporarily displace or split the PV a couple times already. The graphic above shows the PV progression in the Stratosphere at 50 hPa. As time goes on, the Stratospheric PV is shifting into Eurasia and warming is taking place over Canada, the Davis Straits, and Greenland. This should allow for positive heights to build in the Troposphere over the AO region which could finally bring our AO into a permanent negative state. The NAO will definitely neutralize and might even trend slightly negative, but I am not yet convinced it reaches an anomalous negative state like many predicted this winter. Until the QBO reverses, expect an NAO mainly around neutral to positive. 

This progression is also apparent at the 30 hPa level. The lag effect for this to reflect at H5 is usually 7-10 days, which would take us into late Jan/early Feb.

Like the Stratosphere, the MJO has also not cooperated as well as we would have liked given that we're (supposedly) in a weak El Nino ENSO. Some have argued that the extremely negative QBO or the active sun are the culprits to why our atmosphere has not responded to the +ENSO. There is probably merit in those theories. The Pacific Jet has been unusually amplified which has taken a toll on our Pacific pattern this season. The PNA has struggled to stay consistently positive despite the +PDO in the east-northeast Pac. The STJ has been weak with little to no influence on our upper air pattern yet this winter. 

Currently we're in phase 7 of the MJO which promotes higher heights in the west U.S. and the northeast Pac. This signals for a -EPO/+PNA couplet. It also suggests there should be higher heights into the Arctic and NAO regions but there is some resistance there given the current state of the Stratosphere. Both the GFS and EURO want to take the MJO into the COD (circle of death) next week, but the biggest difference is the GFS comes out again into phase 8 then 1, while the EURO stays in the COD. An MJO in the COD has no influence on our upper air pattern. Given the struggles we have seen with the Pacific Jet and the lack of blocking, we absolutely want the MJO to have an influence on our pattern going forward so it's imperative the GFS verifies here. 

Put it this way: if what I said about the Stratosphere comes to fruition with the PV shifting into Eurasia, then there will no longer be resistance in the Arctic and NAO regions for higher heights to build there. An MJO in phases 8-1 typically bring about a -AO/-NAO. This may be our only shot in trying to overcome the -QBO. 

That being said, OLR anomalies show active tropical weather or convection east of the Dateline over the next 6-10 days. This is why we're currently seeing an MJO pulsing in phase 7. The big question then becomes...can this convection continue its propagation eastward? It's hard to say right now since these are current observations, but seeing convection building again over the Indian Ocean in the Day 11 range with suppressed conditions closing in on the Dateline again does NOT look favorable to me. The GEFS have done a much better job than the EURO this season, so maybe they're seeing something I'm not, so lets hope they verify and the MJO can get into phase 8. As the composite graphic shows, an MJO in phase 8 supports a continues -EPO/+PNA with a stronger signal for a -AO/-NAO to develop. 

The 00z EPS show a nice -EPO/+PNA pattern in the west with a mean trough on the east. The issue remains the AO/NAO where they both look to remain mainly positive this run. Keep in mind the EURO has the MJO collapsing into the COD, so of course it will show lower heights over those regions compared to the GEFS. 

Here were the 06z GEFS and they have noticeably higher heights extending into the Arctic and even Greenland. 

Let me be clear about something: The pattern going into the end of this month and early February is NOT screaming Godzilla. It is, however, a much improved pattern than where we have been so far this winter and for that matter the potential to get at least a moderate snowfall is higher. The flow on the east is still too fast, so we would have to get good timing with the ridge axis in the west and the northern/southern stream phase on the east. I can see a Miller B type of storm come out of this pattern. 

If one thing is certain, it will be that the cold air has staying power and the month of January is likely to end well below normal. Anytime Pacific blocking develops that is a signal for arctic air masses to intrude into the eastern CONUS. Expect below normal cold through the end of the month. 

Potential Storm Systems

Wednesday January 21st Clipper: 

There has been a lot of waffling on latest guidance on the intensity of this clipper storm. Since this is all northern stream driven, to what degree the energy digs and consolidates will determine how much it deepens and where it tracks. 

Today's 12z GFS is doing pretty much what the 00z EURO did last night. There are two pieces of northern stream energy, one over the Mid-Atlantic and the other over the Midwest, that remain separate and de-amplify the east coast trough. The clipper would have looked much better at the surface if those energies consolidated because the trough axis would sharpen up and a storm would try to come up the coast. At this point, I probably would not expect more then a minor event in the order of a coating to an inch or two for the area. If future runs show better consolidation over the next couple of days, this could turn into a 2-4/3-6 ordeal. I would bet against that for now, but I'll be sure to keep you updated. 

January 24th-27th Storm: 

This is the next time frame to watch for a bigger storm to develop. 

The 12z GFS looks very progressive in this time period with a trough axis positioned too far east and minimal northern stream energy interaction. 

The GFS Ensembles have a large spread and are not so much in agreement. They at least develop the coastal storm but do so too far off the coast. You can tell when guidance is struggling with a storm system when the time frames are all mixed up. Some have it on the 24th, others on the 26th. The various upper air energies circulating the country makes this a complex situation for the models to handle. Once they realize which vort to focus on, we'll begin to see more agreement. 

The 00z EURO from last night looked much better. A sharper looking trough with northern stream energy digging in for a phase, but the storm tracked too far off the coast. Better ridge orientation in the west would have brought the storm up the east coast. You can see both models differ on where to place the main axis of the western ridge. It actually almost looks like a Rex Block with a High Pressure dome over a low pressure off of Baja. They look very much like the GEFS. For now, just realize the potential is there. 

Even beyond January 27th there are more threats to look out for. Like I explained in the long range section, if we can get the Stratosphere and MJO to cooperate, it would greatly put our upper air pattern in a better position to deliver us a storm. I still feel a moderate snowstorm is possible between January 24th and February 5th, possibly of the Miller-B variety. We'll see if this pattern can deliver. If not, managing to reach an average snowfall season will reach a higher level of difficulty. 

Enjoy the rest of your day. 

-Frank

Follow these forums! 

http://www.njstrongweatherforum.com/

http://usa-wx.com/

 

Winter 2014-2015 Update

BLOG SONG: "Have A Nice Day" by Bon Jovi

First and foremost, Happy New Years to everyone. If 2014 was a good year for you, do not take it for granted. Try to make 2015 an even better one.

This winter has not gone as planned for long range forecasters who predicted below normal temperatures and above normal snowfall for the eastern U.S. While it may only be January 2nd, long range outlooks from latest guidance for this month are uninspiring. We'll take a look at how December turned out and what is expected in January later on in the blog.

When I put together my Winter Outlook for this season the main variables I focused on were the ENSO, Stratosphere (QBO), NH Snow Cover, Sunspots, then came up with some analogs to reflect past years that matched projections based on those variables. I do not believe 1 specific variable should hold more weight than the others, but I do feel if one is too extreme, specifically an oscillation such as the QBO, it will be the main pilot in the overall weather pattern while the others act as co-pilots.

As explained in the Winter Outlook, the QBO measures the easterly and westerly wind regimes in the equatorial Stratosphere. Once zonal winds reverse from westerly to easterly, that is indicative of a SSWE (Sudden Stratospheric Warming Event) which most likely leads to the development of high latitudinal blocking (-NAO). Exactly where the blocking develops determines whether or not it would benefit our Atlantic pattern.

The SON (September - October - November) QBO values were -21.64, -23.24, and -23.65, respectively. The extremely negative state of the QBO indicate that zonal westerly winds have been dominating the equatorial Stratosphere. We need them to reverse to easterly to get our SSWE and eventually help change the 500mb pattern to promote higher heights in the AO and NAO regions of the Arctic. The December QBO value is not in yet, but observations show that it is still in a highly negative state which is not what we want to see if you're looking for a developing -NAO/-AO couplet.

Lets bring back the rising QBO table to refresh our memories on how this works. A QBO in an extremely negative state, such as what we're in now, that collapses toward a neutral/positive territory brings about an above normal chance of a -NAO developing. History shows that most Meteorological Fall's that had an extremely -QBO ended up seeing a SSWE that brought the QBO index rising toward neutral (-8 to +8) in December or January. Historical trends say that if the QBO has been in an extreme state for 5-6 consecutive months, whether it be positive or negative, it usually always reverses in the subsequent 1-3 months. However, that has not yet happened to our QBO this season and January makes the 7th month. A possible reason why higher heights have struggled to form over the Arctic or Greenland. 

That said, July-December (6 months) the QBO has been highly negative and we still have not seen a reversal with the zonal winds. This is something that many long range forecasters, including myself, did not expect to happen since it is not common. What ends up happening is the +ENSO/MJO act uncharacteristically and the Pacific Jet turns very active, a big reason why the PNA has been mainly negative. 

This image represents the H25 wind speeds and is a useful tool in analyzing jet streams. Study shows that there is a direct correlation with the strength of wind and the strength of storms. As you can see, the jet streak over China at the 250 mb level is very strong and fast, around 215 kts. Recall that there have been several powerful Typhoons this past summer and fall, notably Typhoon Nuri. There has also been a train of potent cyclones that have tracked the northern tier of the Pacific these last couple of months. The strong Pacific Jet is a likely cause of these strong storms, as well as a culprit why our weak El Nino has not behaved as it's supposed to. According to NOAA, ENSO-Neutral conditions continue despite the SST's along the Equatorial Pacific suggesting otherwise. Additionally, positive OLR (Outgoing Longwave Radiation) has persisted over the Dateline which means convection is weak and precipitation is running below normal in areas that usually see above normal precip. during +ENSO events. In other words, the atmosphere is not behaving like it should during an El Nino regime and is a reason why NOAA has not declared it one...yet at least. This may be a reason why the MJO has been in mainly unfavorable phases, since negative OLR has been constrained near the Philippines. The strong Pacific Jet in conjunction with our neutral ENSO are the main reasons why our PNA has struggled to remain positive, though fortunately the EPO has been steadily negative which is a reason why we're currently in this cold spell. 

Getting back to the QBO, I went back and researched years that had highly negative consecutive QBO values from July-December and you have to go all the way back to the 60's and 70's to find a few. These years include 1965, 1970, 1972, 1974, and 1979. 

Here is what their December 500mb pattern looked like:

Not very pretty. The glaring commonality between all of them is the +NAO/+AO state with a mean ridge pushed back near the Aleutians, resulting in a -PNA. This is pretty much how our December transpired. 

December 2014 500mb:

A distinct difference is our recent December had a much more robust -EPO signal compared to those other years. The Aleutians have experienced below normal heights thanks to a pattern retrogression that occurred around mid-December which has helped our -EPO, whereas the other strongly -QBO years and their December H5 experienced a neutral or +EPO. 

Keep in mind the above maps are upper air maps, not surface maps. This is the temp. departure from normal image you get when putting together that analog package for their Decembers. 

December 2014 temp. departure was flat out warm for the entire country:

Central Park, NY total snowfall (December - March) in those years: 

1965-66: 21.4 inches

1970-71: 15.5 inches

1972-73: 2.8 inches

1974-75: 13.1 inches

1979-80: 12.8 inches

CPK, NY for 2014 is currently at 1.0 inch with December through and January's 1st half not looking so promising either. 

In case you were wondering, the ENSO forecast for those winters were all mixed. A couple moderate Nino's, a couple moderate Nina's, and one ENSO-Neutral. Hence why I do not think the ENSO was a big driver in those winter seasons. 

As bad as those years were snowfall-wise, they all had a fairly cold February (shown below). It is important to know most of these years, besides 1965-1966, saw their -QBO's begin to crash by December. It was not until February of 1966 that the QBO rose to -17.14 (still fairly negative). 

If we take a look at the GEFS & EPS we'll see what they are predicting for the period after January 10th. Between now and January 10th we should be in a mainly below normal temp. regime thanks to the -EPO. If we can sneak in a storm or two while the cold is around would be great. After that period, the -EPO could break down while the +NAO/+AO regime persists. 

12z/01 Euro Ensembles:

You see that we lost the above normal heights in the northeast Pac. and Alaksa while the PV is bottled up in the Arctic. 

Continuing out into mid-January and you'll see the +EPO signal grows stronger, the PV is nowhere to be seen, and there is a zonal flow in eastern Canada and the U.S. There is a +PNA signal though, so that could be a good thing as long as we have a semblance of cold air to help bring us a light to moderate event. 

12z/01 GEFS:

GEFS also have the PV up in the arctic resulting in a +AO, but notice they still keep in tact the -EPO in conjunction with a -EPO. If this is true it would help keep a mean trough in the eastern U.S. even after the January 10th period. 

And that pattern continues into mid-January according to the GEFS. But the main issue still exists: there is no semblance of a -NAO/-AO and consistent +PNA on either models. If the Pacific Jet is going to be a problem, it would greatly help us if we could get help from the Atlantic but that is not happening any time soon. 

Updated Winter Forecast

Taking all of this data into consideration, I have decided to scratch my original winter outlook of below normal temps. and above normal snowfall. My new forecast (January-February 2015) consists of temps at average to slightly below with below to average snowfall for the area. I think if the Stratosphere can gets its act together, and there are signs heading in that direction, we could still possibly salvage a winter season of at least average snowfall for CPK. If not, expect a below average season in the snowfall category with mean storm tracks either to our north or west. 

I felt this update was necessary instead of waiting until the end of the winter to see what happened. Rather, lets see what has already went wrong and examine what needs to go right in order to salvage at least an average season. 

We'll see what happens! Enjoy your day. 

-Francesco Paparatto 

Feel free to register to the forum: 

www.njstrongweatherforum.com 

or 

www.usa-wx.com