March 28, 2016 Mo Mo

I hope everyone had a nice Easter with their family and friends. We're starting Monday off on a dreary note. Rain should come to an end around Noon today. The rest of the week looks fairly mild with temps in the upper 50's to low 60's. By Thursday afternoon into early Friday, another round of rain is expected from a cold front. Less then 1 inch of rain is expected. 

Rain Thursday afternoon

Once the cold front passes through a rush of cold air will storm into the Northeast. Do not rule out a snow squall Saturday afternoon into the evening. This could possibly be our last cold blast of the season. Temperatures are expected to get down into the 20's (teens N&W) with high's only in the upper 30's to low 40's. 

The American and European Ensemble suites are in agreement the Polar Vortex will track southeast of the Hudson Bay and force a trough over our area. 

Notice how the ridge pops in the west and there are some higher heights over Greenland. This remains a transient pattern so the cold will not be long-lasting. I think by the time we get to Tuesday the 5th the cold will begin to moderate and temps will gradually warm up again. 

Temps Sunday morning (April 3rd) are only in the 20's and 30's across the region. 

Temps 2pm Monday (April 4th - Yankees Opening Day) will only be in the 40's. Bundle up if you're going to the game!! 

That is all I really have to report in today's Mo Mo. A couple rain shots this week, maybe a snow squall Saturday with an arctic blast, and back to warm temperatures by the middle of next week with more rain chances on the horizon. MY 2016 SUMMER OUTLOOK WILL BE OUT SOMETIME IN APRIL. Be on the lookout! 

Have a great day. 

Best,

Francesco Paparatto 

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www.njstrongweatherforum.com

Come Fly With Me Through The World Of Model Mayhem

There are significant differences between the EURO and GFS models in regards to the Sunday into Monday storm. The EURO has a strong surface low tucked near the coast bringing over 12" of snow to the area, while the GFS scrapes the area with just a few snow showers. The caveat is the GFS Ensembles are closer to the coast and the EURO Ensembles are even more impressive and further west than the EURO OP. It would not be a big snowstorm without model disagreement! 

Here is a look at today's 12z EURO 500mb height anomalies valid late Saturday. This is a good look of how the pattern will set up. As explained yesterday, we will have a -NAO/+PNA to work with. The higher heights over and east of Greenland is a nice -NAO. Not classic but it's our best block all winter. The ridging in the west into the Arctic is a very impressive +PNA/-EPO. This is what will help drive the northern energy and arctic air into the northeast. The goal is to get a phase to occur between the northern and southern phases. As shown yesterday, we do not need a phase to get a big snowstorm since the southern energy is strong on its own, but I would feel comfortable knowing a phase will happen because it lessens the odds this storm goes out to sea like the GFS OP is trying to show. 

Today's EURO at 500mb is almost a replica of yesterday. There is no phase but the southern energy is stronger today, so the surface low is pulled closer to the coast and those west into PA get into the action. Notice how the northern energy is still over the Great Lakes but it's trying to dig quickly into the coast for a phase. 

Recall yesterday the EURO was showing a surface low around 991mb. Now it's closer to the coast and around 988mb. The EURO Ensembles are even more impressive. Some members are around or sub 980mb with the low so close to the coast that the Jersey Shore and Long Island see rain or mixing. 

The 200mb jet streaks and wind vectors suggest this storm has a clear path up the coast toward the Benchmark. It will be interesting to see how dynamical this system could get. If there is no phase, the storm may struggle trying to wrap colder air into its core so dynamic cooling would be difficult to achieve. This may bring mixing concerns to parts of the immediate coast, including NYC. Even though the EURO is not showing this, it's still worth noting soundings may be showing a warm layer somewhere. This is why it's critical we at least see a partial phase with the northern energy. 

The GFS is off the coast because it rushes the southern stream ahead of the northern stream and the vorticity never wraps itself into the trough. Everything looks a little fast and pretty strung out. It does not have support from its own ensembles nor other guidance such as the SREFS and GGEM. The only reason I am not completely discounting the GFS is because of the northern branch remaining disjointed from the southern one. However, the southern branch should be able to manage a storm at least near the coast given the -NAO/+PNA/-EPO. 

Tomorrow will be a critical day of model runs if you're a winter weather enthusiast. Either the EURO holds serve and regains its reputation as "king," or the GFS will out perform it once again like it did a few times this winter. At this moment, I am leaning in favor of the EURO and its Ensembles because I feel it handles -NAO type storms very well. and it has support from other guidance. Therefore, I am currently forecasting a 6 to 12" snowfall for the area beginning midday Sunday into the 1st half of Monday. The potential still exists for a Godzilla (12" or more). We'll see!

Enjoy the rest of your night. 

Best,

Francesco Paparatto

______________________________________________________

www.njstrongweatherforum.com

Tracking A Spring Godzilla Between March 20th-21st

El Nino has dominated our winter pattern. Above normal temperatures with very few snow chances. Jonas was our big Roidzilla - a historic storm - but this season leaves winter weather lovers wanting more. After experiencing temperatures in the 80's last week I think it's safe to say most put this lackluster season to rest. Looking at the latest weather guidance I think it's fair to say Mother Nature has other plans. March may go out like a lion. 

Earlier in the month I noted the 2nd half of March may be on the cooler side. There were signs of the NAO going negative and the ridging returning to the western half of the U.S. According to latest guidance we are heading in that direction. These combinations in an El Nino flow are a recipe for big east coast storms to form. 

The NAO is definitely heading into a negative state. This is also shown on the 500mb height anomaly graphics which I will get to soon. This is important because not only is it just the 2nd time this season the NAO will go negative, but it's key to getting an east coast snowstorm happening. It will try to slow down the fast Pacific flow and give upper energies in the atmosphere a greater chance to phase. 

The EURO on Saturday morning shows a large Upper Level Low over the center of the country. Notice how the other ULL over New England is trying to exit stage right by moving north and east. This is critical. The greater the separation between these two ULL's, the higher the odds are of this possible Godzilla on Sunday coming to fruition. The reason being the eastern trough has room to amplify and the upper level vorticity gets wrapped in instead of stringing / shearing out like the GFS shows. As this ULL digs south, heights along the East Coast rise (Atlantic Ridge) which paves a path for this storm to track up the coast. 

By Sunday morning notice how the ULL that was over New England is out of the picture. In response, the Atlantic Ridge is able to amplify which gives the upper energy associated with the ULL in the center of the country a clear path to track northeast instead of due east. Additionally, the NAO is negative at this juncture so this usually keeps surface low pressure systems closer to the coast instead of well off the coast. The +PNA gives us hope the northern energy coming down from Canada will try to phase into the southern energy. If successful, you can expect a Roidzilla-esque storm to impact the area Sunday into Monday. Right now, the EURO shows a Godzilla storm and that is WITHOUT a phase. So, imagine if it begins showing a phase. 

This is what I mean. The storm the EURO shows hitting the area on Sunday is all southern stream driven. From the map above there is no clear phase between the northern and southern branches. That goes to show the potential this system has.

EURO verbatim has this at 989mb. If a phase were to happen, not only would the surface low be tucked in closer to the coast but the pressure or strength would be sub 970mb. Right now NYC Metro is absolutely hammered on the EURO. With a phase - which is entirely possible due to the -NAO/+PNA duo - areas further west would also get into the action while much of the region sees a crippling blizzard. 

Here is the EURO again Sunday morning looking at 500mb height anomalies. The block in the northern Atlantic into Greenland is key in this setup. It really does help slow the flow down and allow the upper energies to convene along the coast. Also, the separation between the ULL's is also very important and the EURO does a nice job in showing this. This is why it is the most bullish model with the Godzilla on Sunday. 

Both of these images are from the GFS model. The biggest difference between the American and European model is the lack of separation with both ULL's, and the inability of the ULL in the center of the country to dig deeper into the eastern CONUS. The GFS looks very progressive with sheared out upper energy. This is a typical bias of the GFS. Also, I feel the GFS struggles with storms involving a -NAO. I do not think it does a good job of recognizing the block which in turn effects how it handles the pattern downstream. 

CONCLUSION:

I actually feel very good about this storm coming to fruition for the area. This is the first storm all winter I have felt good about. It took me awhile to get around to Jonas, but for some reason my gut is telling me this one will happen. I really like the set-up with a -NAO/+PNA. I like how even with no phasing on the EURO it still manages to get a surface low close to the coast with enough cold air in place to support snow. I think over the next 2 days we will continue to see waffling. By the time we get to Friday I think models will begin to hone in on a Godzilla-type storm affecting the area mid day Sunday into Monday late morning. 

We will see what happens! Have a great night. 

Best,

Francesco Paparatto 

_________________________________________________________________________________

www.njstrongweatherforum.com

Warmer Times Ahead

Is it safe to say the January Roidzilla was the highlight of the winter? I mean, I don't even think it is close. And the sad part is the Roidzilla, aka Jonas, did not bring the 2+ feet snowfall amounts to a widespread area. It was fairly concentrated from central and eastern NJ through NYC / LI. Central Park got below zero and we even had a severe weather outbreak. I think those may be the top 3. I think it is fair to say winter has ended. We will see record warm temperatures this week and even more mild weather on the way for the following week. 

The EURO (top) and GFS (bottom) suggest temps on Thursday afternoon will reach the mid 70's. That is about 15 to 25 degrees above normal for this time of year. May weather in March, who would have thunk it?! 

Be on the look out for rain late Thursday into early Friday. The bulk of the rain will stay to our north. Both the GFS and EURO models are in agreement of that. Do not rule out a spotty shower though. High Pressure if off to the south and east which keeps our temps fairly mild. More rain is possible Sunday into Monday next week. At this time it does not look like a high amount. 

One reason we are seeing these mild temps is because the Pacific Jet is crashing into the west coast of the U.S. This keeps the PNA negative with frequent rain storms affecting the PAC NW. Notice how the ridge builds over the east with a strong High off the east coast. 

This pattern looks to last through the week of 03/14 as well. The PNA stays negative and the eastern U.S. stays under the influence of a southeast ridge. When the Pacific Jet is strong and in control it does not bode well for cold weather lovers in the northeast. 

By later in the month - say by the 19th - the pattern tried to flip to a split-flow. This shifts the Pacific Jet south into the SW CONUS and brings the northern jet driving across the northern tier of the country. The southeast ridge moves east and a trough tries to settle into the eastern U.S. At this time I do not think it will lead to any wintry weather, but it should get cooler or at least get to average later in the month. Honestly, the weather moving forward looks very boring. Personally I appreciate the weather turning a bit milder, but storm-wise I do not see anything significant. 

El Nino should be weakening drastically as we head into April and May. By the summer we should begin talking about La Nina and how strong it may get by winter 2016-2017. We still have a long way to go before we reach that point. For now, our pattern should continue resembling one of El Nino for the most part. 

Have a good night!

Best,

Francesco Paparatto