Friday, October 28, 2011

Batten Down The Hatches... (Snow Map)

Let's talk snow!? First off I am much more worried about this storm than any others I have personally experienced. And that's because the leaves have not fallen off the trees yet. In fact some urban areas with exotic and invasive tree species still have green! It only takes around 2"-3" of snow to take down a tree with leaves. Now what if you get 8"-14"? And some models even suggest up to 20" in some locals (highest terrain). This is a major problem, and power outages are not just likely but certain. Here aresome tips:

-Take down any outdoor screen houses/umbrellas
-Don't park under tree limbs!
-Keep the space heater ready, if power goes out so does heat!
-If you need to keep food items cold outside works. Unless a bear comes...
-No matter your age, take breaks while shoveling. This snow is often called "cardiac snow".
-Do not walk/stand under stressed trees with foliage
-Above all, don't under estimate the storm just because it's October...

Elevation will still play a major role in this storm, but so does the exact track. I'm going to take the average liquid equivalent of all models and use that to draw my map while keeping terrain into consideration. Let's look atthe QPF maps:

NAM: (1.5"-2.00")

NMM: (2.00"-3.00"+)

GFS: (1.50"-2.50")

JMA: (2.00+)

Now that we have a good idea of precip amounts let's look at the sounding:
Above is a vertical profile of the atmosphere and the red link represent freezing. The long blue line are temp and dew point. When they come close to each other it means the air is saturated, in this case it's not clouds but HEAVY precip. If you look closely the lowest level is above freezing to start the storm. This means areas below 1,000 feet will start off as rain. Above that expect all snow from the beginning. To those of you below 1,000 don't fear, the rain falling will actually cool the surface quickly and change it over to snow. It's better known as evaporational cooling.

Let's progress to the height of the storm:
Now that's what I call a PERFECT snow sounding. No significant upper level inversions, which means no mixing! At this point in time snowfall rates could be near 2"-3" an hour! Highest elevation will be colder than lower ones, which means higher snow ratios and thus deeper snow.

Now that we cleared all that up let's look at the snow map/forecast:

Map considers these circumstances:
Most affected (Morris, Warren, Sussex, western Passaic)
-Average precip total (QPF) for entire area = 2.125"
-Snow ratio of 8:1 to 10:1 by hour 6 of event
-Surface temp tomorrow for areas <500' = 34.1
-Surface temp tomorrow for areas 500'-1,000' = 32.5
-Surface temp tomorrow for areas 1,000'-1,500'= 30.8

-Also expect gusty winds out of NE
-Thunder snow is being forecasted
-White out conditions at times

Be safe and stay classy...

P.S. What do you think of this new format for snow map blogs? Does it help with understanding the event? Comment or send email to

Thursday, October 27, 2011

It's Snow Time!

Well, the chances of it snowing look pretty good for the area. Actually, I would say it's almost certain at this point. The european model was the first to catch onto the system and now most operational models are showing the same scenario. The only question is how much snow will fall?

Let's take a look at the latest GFS:

Essentially all models are showing this now with the exception of the NAM. It will probably catch on by the 18z run time. Basically we just need to know how much liquid precipitation is forecast and translate that into snowfall amounts. The GFS forecasts around an inch liquid for Sussex County, so that would mean around 4"-10" inches of snow! It's a large range because lower elevations *will* get less snow than the higher terrain because the temperature factor.

Take a look this sounding for Sussex County:

Any forecasts you see of rain/snow/mix are completely inaccurate. This storm will bring all snow to the area with no mixing. Nothing even suggests such a thing so I'm not sure what those forecasts are about. Anyhow, the sounding above shows there will be no warm layer inversion so it's either rain or snow. No sleet or freezing rain thank god! High temperatures forecasted by NWS are in the mid and upper 40's! That's wrong. When the precip falls (especially heavy) it will cool the atmosphere and temps will struggle to rise above 32 degrees in the higher terrain and 35 in valleys!

I still need to make a snow map. It will be out tomorrow.

P.S. It looks the rain today may end as a brief period of snow in some spots around 00z!

Tuesday, October 25, 2011

Is It Time For Snow Already?

Let's get this straight. Some computer models suggest a storm moves through Thursday and brings our area mostly rain with a potential change over on the back side for parts of Sussex County. Personally I think the precipitation will end just before the cold air advances, essentially only bringing us a chilly rain event. Now currently there are two models that suggest a second system will ride up the coast and throw nearly an inch of liquid precipitation into cold air (this includes the entire state). Let's take a look at these models:

JMA (Japanese Model):

Okay so the model above shows high winds and nearly 20" inches of snow across New Jersey, which I do not believe. This model always has an issue with predicting total QPF (total precip) but the physics in the model seems to be somewhat trustworthy. The blizzard depicted above is not very likely, but it does help support the idea of some kind of snow event.

ECMWF (European Model):

Above is the snowfall forecast for hour 105 and it's only a three hour increment. The total snowfall predicted by the EURO is 6"-10"! This model has been consistent for the past several runs, something that meteorologists look for when analyzing model output. Also the EURO is known for having better physics in the model than most others.

So far no other models have gone to this idea, instead they just pass off the storm off the Mid-Atlantic coast. As of right now it's too far out for making any kind of calls, but check back tomorrow as I will be posting on the very latest model output and give you my personal opinion.

P.S. Winter Forecast should be out by the weekend

Monday, October 24, 2011

First Snowfall of the Season?

Take a quick look at the sounding. It suggests snow Friday morning for NW Jersey and even into the city! Check back later tomorrow. It's time to start blogging :)

Tuesday, October 4, 2011

Time For Winter Forecast Pondering...

This isn't my official winter forecast just yet. Consider this more of a pre-cast of sorts. Let's start off with the ENSO or El Nino Southern Oscillation. The ENSO phases La Nina/El Nino are based off whether the surface temperatures in the Pacific are colder or warmer than the normal. The Pacific is the worlds largest ocean and changes in surface temperatures can greatly affect the weather here in New Jersey. Let's look at the PDO first since it has a strong correlation with the ENSO phase. A warm phase in the PDO is when the water temps off the west of Canada and Alaska are warmer than normal, thus El Nino's tend to be stronger and occur more often. A cold phase is the exact opposite and allows for more and stonger La Nina's.

As we can see from the chart above we are in a cold phase of the PDO, and that means La Nina's should dominate the Pacific over the next 10-20 years since the PDO works in 30 year intervals typically. This years ENSO phase should be similar to last years La Nina which spells colder weather for us here in Jersey, or at least for the first half of the winter.

I always look at the current solar activity when making a winter forecast. Little is known about how the solar cycles affect the climate, but it doesn't hurt to look at it.

Above is a graph of the last solar cycle that spiked in late 2003. That solar cycle maximum was much weaker than what we saw in the 90's. A typical solar cycle lasts for around 11 years from minimum to minimum but the most recent went for over 13 years, something we haven't seen since the Dalton Minimum in the early 1800's. You may have heard of some solar storms lately but it's just the beginning of solar cycle 24 which is forecast to be much weaker than any other in modern history. Just take a look.

What will be the affects? It's almost impossible to say for sure, but past studies have suggested that low solar activity could throw the planet into a cooling phase. A good paper I suggest is by David Archibald who has been extremely accurate with his predictions over the past several years. Even better than NASA's predictions which originally forecasted a strong solar cycle which would peak in 2012. That's not going to happen, not even close. "Solar cycle 24: Implications for the United States" is the paper by Archibald and can be found on his website:

A winter can be cold, but that doesn't necessarily make it a good one. There have been plenty of cold winters that lacked precipitation. That brings me to the next items on my list, the NAO or "North Atlantic Oscillation" and the AO or "Arctic Oscillation". Both of these have negative and positive phases, and for New Jersey we like to see them negative together. Over the past two winters we have had some crazy weather events and most of them were a cause of stratospheric warming events at higher latitudes which affected the AO and NAO. I know, you have no idea what I just said. I'll explain.

The animation above shows temperature anomalies in the stratosphere (up high in the atmosphere). Red is a warming event and blue is cooling. If you look closely at warming events in the animation you see how the jet stream buckles where ever they pop up. This is called blocking and allows for some wacky weather. Such as Mountain Creek in NJ getting 28" of snow and Killington VT gets 2" of plain rain during the same event! It happened in February of 2010 and guess why it happened? That's right, a blocking event directly related to a strong stratospheric warming event. For you global warming fanatics, no this is not because of global warming. A warming stratosphere happens when the troposphere (the surface, where we live!) becomes colder than normal. The opposite goes for cooling events in the stratosphere.

Last year these stratospheric warming events continued despite the end of a El Nino and a start of La Nina. A major warming (though not as major as the year before) event happened in mid-December followed by 32" inches of snow in eastern part of New Jersey. January brought more warming events which lead to the snowiest month in history for much of the state. The signs are obvious and need to be looked at with a fine tooth comb. Looking through all the signs, only one thing has changed since last winter. That being the phase of the QBO or "quasi-biennial oscillation". And it's shift points toward a more ominous winter than last.

The QBO is basically winds between 10mb-100mb. These winds shift from easterly to westerly every 20 to 36 months. As of August the winds officially became easterly, just like they were in the winter of 2009-2010. Last winter I only expected average snowfall for the region and we went over by about 10"-15". This is because last winters westerly phase of the QBO should have helped to suppress stratospheric warming events. Therefore winter shouldn't have been as bad as 2009-2010, and for NW Jersey it wasn't! I can't say the same for NE Jersey. We have entered a easterly phase of QBO and it means more and stronger strat warming events.

This was only my pre-cast. My official winter forecast will be out later this month. There is a lot to talk about and I couldn't possibly do it in one blog post without putting everyone to sleep. If you ask me, this coming winter might leave last year in the dust...