Thursday, February 8, 2007

-The character of "Chick" in Armageddon, played by Will Patton.

Kahuna 1 GFS Snowfall Map

Evening comment: The map above is a distant forecast by the GFS for total snowfall accumulation ending 1PM Thursday. Yes I'm sure it will excite many of you. This would be a powderhound's dream storm for northern MD, southern and central PA to Jersey and NYC. But I caution these numbers could change drastically, in either direction. Let's let another 24 hours of data come in and revisit this map Sunday night to see where it stands.

Kahuna 1 Maps

The graphic above is what I call the Friday night roundup:
An overview of storm projections from the major forecasting agencies or companies.

WHAT'S CHANGED ABOUT STORM PROJECTIONS: As you would expect, computer models have diverged from their earlier agreement on the storm's track and intensity. The most significant trend which developed on Friday in regarding to the outcome on Tuesday and Wednesday is a much more northerly track...which would expand the region of heavy snow. Consider the current spread among these 4 different models: Upper left is the JMA, upper right is the Euro, lower right is the GFA, and lower left the UKMet. What trends do you see? If you want a larger version, click on the map to go to flickr and enlarge as needed.

Kahuna 1 4-model map

WHAT'S CHANGED ABOUT MY FORECAST? The only major addition is to include New York City and Boston in the region of accumulating snow. I'm not ready to issue a snowfall range for these areas until I see if computer model trends will be reflected in the precip (QPF) projections to be issued on Saturday.

WHAT'S THE BASIC IDEA WITH THIS STORM? We're still looking at just a "Kahuna" at this stage, which means a significant to major plowable snowstorm that should not end up becoming "crippling." I say should not because there is growing concern from examining those computer models that perhaps one of them is showing the more likely solution. Were the UKMET (operated by the British Meteorological Service) or the JMA (Japanese Meteorological Agency) to verify, either scenario would drop 2-3 feet snow and paralyze the entire Northeast Corridor. The HPC's (The Hydrometeorological Prediction Center) liquid equivalent map below is as of about 4:30 PM Friday and shows the total precipitation potential for the period 7PM Friday to 7PM Wednesday. This map will be revised later today so click here to see the latest version.

Kahuna 1 QPF 1

Snowfall range: 10-20 inches total accumulation by 8:00 PM EST Wednesday.
Remember final numbers are issued about 24 hours prior, which is set for Sunday evening.

Start time: Accumulating snowfall should be arriving in the West Virginia/Virginia/Central Maryland regions no later than 5:00 PM Monday night, including the DC and Baltimore metro areas

Target region: central Mid-Atlantic including West Virginia, Virginia, Maryland, the DelMarVa peninsula, southern/central New Jersey and southern Pennsylvania below the 76 turnpike from Philadelphia west to Bedford, PA.

Evolution: I should re-emphasize this event may progress out as a 2-part storm, with the lighter, weaker part arriving Monday into Monday night, (a front-runner moving from Southern Plains to the the Tennessee Valley) and the second much stronger part taking over on Tuesday (a coastal Low developing somewhere near the Carolinas and then possibly taking the turn up toward New England)

End time: If Part 2 of the storm develops as expected, and turns up the coast then backlash snows will continue to add bands of brief but heavy accumulation Wednesday morning. For the Mid-Atlantic, all precip should end by 9AM, for northern New Jersey-New York and Southern New England, the period of heaviest snowfall would occur from early Wednesday morning until late that evening, ending most likely by midnight as the storm races to the Canadian maritimes.

Notes: There remains the possibility some areas, especially in the MD/VA/WV Appalachians in addition to east of I-95 (interior bayside areas of Maryland and along the DelMarVa) that could see amounts exceeding the 10-20" range due to 'banding' that often sets up along the backside of the receding storm. This would especially be the case if we have the classic "Nor'easter" arrangement that's being indicated by some of the computer models.

Kahuna 1 Euro 2

This is Friday night's European model projection for 7AM Wednesday morning showing a departing all-out blizzard along the Northeast United States, coupled with a sprawling Arctic High hugging the storm to the west while funneling extremely cold in to the eastern two-thirds of the country. The HPC is currently leaning toward the Euro solution but not buying it outright, as evidenced in their Saturday morning discussion. The US-based GFS (Global Forecast System) has shown to suppress the storm significant, and the HPC has essentially ruled this solution out. If the GFS begins to trend back toward the Canadian, British and European projections, that could spell deep trouble for the already packed grocery stores along the East Coast. Were the GFS to come around toward a more northerly, colder solution, you would quickly see much stronger wording in your local forecasts and "Special Weather Statements." Either way, I expect Winter Storm Watches to start flying by Sunday morning or even late Saturday night for portions of the Ohio/Tennessee Valley and western Mid-Atlantic.

If you have airline travel plans departing or coming to the Mid-Atlantic region, I hope by Monday afternoon you are either arrived or well on your way out of here if you want to avoid flight delays and cancellations. If you are traveling by bus or car, I recommend planning to reach your destination by Monday evening at the latest if you want to avoid being caught in a winter nightmare on Tuesday morning. Having driven 8 hours at 30 mph near-blizzard conditions of the February 2003 storm, it's an experience I would not wish on anyone. Lastly, here's a picture of the Pennsylvania turnpike at the height of the storm on Sunday morning, 2/16/03.


In conclusion, perhaps you'd like to know the backstory of the headline. All the scenes in that movie involving the character of Chick with his little boy and wife always choke me up, every time I see it. For those of you whom have not seen this movie, you should rent it during Kahuna # 1, the science is a little off, but the overall theme is inspiring. The first series of scenes is when Chick, who is about to embark on the historic mission to save Earth from an asteroid impact, visits the home of his wife from whom he is separated, to say that he is sorry for the pain he's caused her in the past. The little boy comes to the door and asks "Who's that man?" The mother replies, "That man's a salesman, now go inside." Then he says that great line which is today's heading, and leaves behind a little Space Shuttle for the boy. Later, when Chick is seen by network news boarding the Shuttle, the boy sees this, and says "Mom, that salesman is on TV!" followed by the mother saying, "That's not a salesman, that's your Daddy." The final scene of the movie that always gets me is when the Space Shuttle crew is walking down the tarmac, it looks as though no one will come out to welcome Chick home from the mission, and then... around the corner comes running this cute little boy right into his arms. (wiping tears) Now as the father of two sweet little girls, this particular scene has special meaning for me more than it ever did. The point of this essay is to say that if our big storm pans out to everyone's expectations, and Mother Nature gives you some extra time at home, I hope you will take advantage of that time to let your family, or friends or those close to you know how much they mean to you.


terpguy said...

From previous post:

I didn't want to say anything, as I still consider my self a rookie, but I was getting a feeling that there might be two systems coming.


Foot's Forecast said...

Holy smokerokies, you are not going to believe what I just saw on the GFS for 8PM Monday the 19th.

A SuperKahuna with 1.5 inches of liquid over the I-95 corridor.

That would easily be 12" +

Imagine being clobbered by K1, then being redoubled clobbered again by SK2. What could this mean?

Only 1 thing: For schoolchildren and teachers across the land, July 4 will have a new and special meaning: It will truly be an Independence Day.

It;s just one run of the GFS but I will post it for fun later.

Frank said...

I always wanted two storms back to back where we get direct hits, and having it stay cold so it all doesn't melt in between storms. One of these days that will happen, and hopefully it will happen in the next 15 days! :)

Mr.B said...

Am I left out or what Mr. Foot?

"Main areas targeted for heavy snow and potential for icing are what I explained yesterday: central Mid-Atlantic including West Virginia, Virginia, Maryland, the DelMarVa peninsula and possibly southern/central New Jersey. Today I'm going to add southern Pennsylvania below the 76 turnpike from Harrisburg east to Philadelphia."

B said...

excuse my ignorance, but can someone define 'Kahuna'?


chip said...

As Inspector Gadget would say, Wowsers! So are we looking at the possibility of 10-20 next Tuesday to Friday and THEN ALSO maybe over 10 the following Monday night?? That could mean off school Wednesday, Thursday, Friday, (off anyway Saturday, Sunday, Monday) and then off Tuesday, and maybe Wednesday...? Don't just stock up on bread, buy a bread machine, flour, and yeast! We await more info as it develops and family time permits -- thanks, Mr. Foot! PS Kahuna is short for Big Kahuna, i.e., a really big event

Foot's Forecast said...

We've used the term Kahuna on this site to define a major snowstorm, but in recent years it has been delineated into three levels:

Kahuna or Big Kahuna = Significant snowstorm (like Dec 5-6, 2002 or Feb 11-12,2006)

SuperKahuna = Major Snowstorm
(January 6, 1996)

UltraKahuna = Historic Snowstorm
(March 12-14, 1993 or March 1958)

then there's ImpossibleKahuna =
Mega Blizzard from Day After Tomorrow

Actually Kahuna refers to a medicine/witch doctor in Hawaii. But it's a fun term so we use it.

B said...

yeh haha, i checked wikipedia and it mentioned medicine doctor in Hawaii, so i was rather confused.

Thanks for the knowledge Mr. Foot. Here's hoping for my first snow day at University [in D.C]

E.H. Boston said...


Maybe I'll leave the country more often for you guys...I-95 is going to get clobbered.

Foot's Forecast said...

Hey Mr. B..sorry for missing you on that forecast. I'm going to extend the line back to Bedford. This might be the storm you've been waiting for. Then again, the REAL President's Day Blizzard is yet to happen.

Mr.B said...

Thanks Mr. Foot.

I got the the weatherlink software for my vantage pro 2. It has a website and it's great. Also I have a weather cam.

You can seen the latest conditions from greecastle.


Current weather


Mr.B said...
This comment has been removed by the author.
Mr.B said...

Site is


TQ said...

"The amount of snow that falls is inversely porportional (sic) to the amount of hype before the storm."

Which is a corollary to Schwartz' Admonition: Snowfall amounts are inversely proportional to the excitement at the Map Wall.

Progs cont to show little in the way of mid-lvl forcing. Flow is progressive. UVMs fm 85G WAA and some semblance of coupled jets in the polar and sub-tropical streams.

I/m expecting another rain storm with some snow on the nrn edge of the shield...just like every other event this winter.

Linda said...

Hey everybody, Weather is starting to get exciting!! I have been away for a few days, as my mom is very ill. My sister and I take turns being with her. So, Mr.Foot, my mom lives on the borderline of Pa. and Delaware, I'm sure you pass it on the way to grammy's house. Which will get the most snow. There or bucks county. I'll plan my next long stay accordingly.I usually go every week for three or four days, and I would rather be home in a storm, but you do what you have to do. I am really excited about the news of the upcoming storms, I don't have access to a computer at my mom's, so it was fun to get home this evening and see all I missed! What a difference a few days make! Heres hoping that we all get clobbered with many Kahunas!!

Andy, Southern York County PA said...

What's the worst case scenario? Could we get 40 inches in a week?

Foot's Forecast said...

Welcome to the group tq. Most of us in this discussion community are not professional meteorologists, nor do we pretend to be one, including me. We do however strive to communicate in a way that nearly everyone around us can clearly understand in plain language. If I were to post something like this...

"Progs cont to show little in the way of mid-lvl forcing. Flow is progressive. UVMs fm 85G WAA and some semblance of coupled jets in the polar and sub-tropical streams."

they'd have my head for trying to talk above them as a superior, not with them as peers.

I'm not going to attempt to translate your analysis, because as a non-professional, I'm certain I'll botch it. Can you translate for us?

Foot's Forecast said...

Andy.. can you give me the nearest town/city from which you base your observations, so I can link it in the Friends section?

My comments about the 240 hr GFS were just to point out that I actually hope that storm does not happen, or is another one of those phantom GFS storms that appears once then never again.

Were that to happen, there'd be at least 30 inches on the ground where I live by Feb 20 (combining next week with the week after) and my district would be out 6-8 days. I'd rather not have to deal with the consequences of such a storm come June when we're all sweltering in a non-AC school building trying to conduct final exams. (Often reaches 100 F on second floor of my school in June).

But, being the powderhounds that we are, you know we're all going to be watching that one verrryy closely.

Foot's Forecast said...

Linda! Welcome back, so unfortunate to hear your mother is now doing well. Hang in there. Hopefully some snow will cheer you and her up together.

I hope these do not become "famous last words" but I am leaning much more towards the heavy snow being closer to the PA/DE line than Bucks County. Of course the models can and will continue to surprise us so there's that back door possibility the storm ends up even farther north than currently projected. I tend to think not simply because the influence of that Canadian/Arctic high is going to be such that it should prevent this storm from completely riding all the way up the eastern seaboard right to Maine. The general consensus, (which changes hourly now) is whatever emerges off the Mid-Atlantic coast will head out to the Canadian maritimes from there and not turn up towards New England. (much to the chagrin of Mr. E.H.)

But then again, since he's leaving the country, it very well could do that just to spite him! :-)

Hope that helps and I'll try to keep your location in mind when I post the storm grade amounts Monday.

Foot's Forecast said...

thanks for the info on your site revisions. I need to update my link with that new address, and promise you I'll look it all over this weekend. Since your NWS forecast is showing a similar 50% chance of snow starting Monday night, I figured it was only fair to include you in the roundup.

All right everyone else, I'm zonked and the storm is still days away. Signing off until tomorrow. I wonder what the 6z GFS will portend when I wake up.

Mr.B said...

Mr. Foot.

Your welcome. Thats not my new site though. It is a new link on my current site.

Can't wait to see your update.

Mr.B said...

Oh and actually you do have my old address on there.

New one is

Thanks again.


Foot's Forecast said...


(Mr.B.. I'm going to bed now)

(Wasn't going to update any more tonight, just revised the main post slightly)

(Don't stay up too late now, at your age you are supposed to get 8-9 hours of sleep a night believe it or not)

Mr.B said...

Welp, now the GFS,Euro,Ukmet,Nogaps suck for my area.

Frank said...

I know what you mean Mr. B. I am starting to wonder if this storm will even make it to NJ. Seems like it may be the same old story all over again for us. But, I am still holding on for a change since we are still many days away.

Unknown said...

These systems have a tendency to track further north over time. It will be an interesting day / weekend checking all the latest model runs. I'll be curious to see what the NAM will show when it comes into range. Back to back large storms in the area doesn't happen that often so if it does that would be a huge bonus for this winter season's storyline.

Unknown said...

Some of the models are trending north and wow... Mr.Foot was on to something with how big this storm might be. The snow blowers might get a big feeding! Still a few days away but always fun peaking ahead.

TQ said...

Mr. Foot...

Sorry about the jargon and MET-speak. Although I no longer work as an operational MET...old habits die hard.

"Progs cont to show little in the way of mid-lvl forcing. Flow is progressive. UVMs fm 85G WAA and some semblance of coupled jets in the polar and sub-tropical streams."

Thanks for the invitation to explain / decode my remarks.

'Progs' are the numerical weather prediction (NWP) model's prognoses, such as the 12HR mean sea level pressure (MSLP) and accumulated precipitation (QPF) charts.

'Mid-lvl forcing' occurs in the atmosphere's 'mid-level' which is 500 mb (sometimes 700 mb) on the familiar constant pressure charts. 'Mid-level forcing' refers to the advection of positive vorticity (PVA) which produces upward vertical motion (UVM). 'Low level forcing' from warm air advection (WAA) also produces UVM, which can be seen on the 850 mb chart.

'85G' is a typo. Should have been 85H, which is shorthand for 85 mb. 5H refers to 500 mb.

UVM can also come from a 'coupled jet' structure at 300 mb where the polar jet (PJ) is located northeast of the sub-tropical jet (STJ). There's a deep layered circulation in the area between these two features where the 'entrance region' of the PJ re-enforces the cold air at the surface and the 'exit region' of the STJ replenishes moisture. It can be a potent combination and is almost always present during the best snowstorms.

Search on 'transverse ageostrophic circulation' and 'jet streak' for more details.

Mr.B said...

If the GGEM would come true, I would jump for joy!! 20-30".

Andy, Southern York County PA said...

Mr. Foot:

I am in Shrewsbury PA. Exactly 3 miles North of the MD line with Baltimore County. My elevation is 970 ft.

E.H. Boston said...

12z JMA is showing an absolute wicked monsta!!!

Here's my thinking...

If the storm does arch up the coast as the JMA and Canadian are showing, expect a widespread fluffy 1-2'+ all along the I-95 corridor.

If it follows a more Mid Atlantic track, like the GFS shows, then expect snowfall accumulations generally snowfall under 1'.

If it follows a track of the NOGAPS, expect 2-4" in central VA.

Either way, I would probably want to be in Balimore and DC for this event, because the chances of you guys seeing 6"+ is probably at about 75% right now, compared to the 25% in Boston.

E.H. Boston said...

Mr. Foot, what is the EURO and JMA and Canadian doing.


Foot's Forecast said...

Happy Friday everyone and thank you for keeping the model monitoring going today. I was busy spewing lies to my students (as some people on EasternUSWx might say) about our upcoming storm. Interesting to see how most of the models are trending further north. I guess NYC and BOS are in the game now, question is how much.

Yes EH I saw the JMA today and showed my students in comparison to a flatter weaker GFS.

Thanks tq for your clarification and followup. This looks to be a great opportunity for us to learn from a seasoned expert and we would welcome your input at anytime.

It's evening family time, dinner, etc so I will be released to a full post update/revision later tonight. Don't expect anything before 8PM! I have no major changes except to say we'll let the northern I-95 corridor play with us now. This weekend I'll be preparing the storm grade amounts and what fun that will be.
Especially for you Mr. B, I'm going to do everything I can to pull this storm in so you get KAHUNAFIED with the rest of us.

Mr.B said...

"Especially for you Mr. B, I'm going to do everything I can to pull this storm in so you get KAHUNAFIED with the rest of us."

Heck ya.

I liked the GGEM it gave me 20-40".

Foot's Forecast said...

About to post a short update now. The GGEM did WHAT? Can I see that link? I read HPC saying lots of spread in the models now, they mostly moved north, trying to figure out how muc NYC and BOS will be in on this.

Working on a short update now, mainly to show QPF changes since this AM and the latest Euro with the SuperK along the NE coast.

WEYTYN said...

Mr Foot- weytyn reporting. what happened to the temperature contest. Tuesday am my actual minimum was 7.4 deg and max was 18.5.

I was way off on my predictions. guess I lose.

Now the bad news......I can't find any toilet paper, bread or milk in any local stores. Is everyone reading your website info now?...and running scared.

I can live w/o bread and milk, but email me a roll of tp quick!

looking forward to a snowy week...bring it on....
even if it is w/o TP.

chip said...

Weytyn, how about I fax you a roll of TP? Okay, one ten-page blank fax coming up! Ha, ha.

Mr. Foot, did I read someone post something about 20-40 inches?? Oi gevult! Eagerly awaiting any new insights, with gratitude, from the Hereford Zone! :)

Mr.B said...

This was the 12Z GGEM.


GFS just sucked!!

Julee said...

A Charmin story

In summers long ago, I worked in a Crabtree and Evelyn (upscale soaps and lotions). When I ordered supplies from the warehouse, I wasn't ALLOWED to say "toilet paper" due to an overly QUIRKY manager. We had to use her more "polite" term, "baby doll" in case a customer was within earshot. Every week, I had to order four rolls of "baby doll."
Life's funny, isn't it?
Hope your grocery stores never run out of baby doll!

E.H. Boston said...

FWIW...all of the tv news stations here are GFS loyal and saying that its going to go all out to sea for Boston.

We'll see.

E.H. Boston said...

Is anyone seeing this 0z UKMET come out.

Its showing a 978mb give or take..low hug the coast bombing it out.


Mr.B said...

Can I get a BOOM!!!

E.H. Boston said...


Let the EURO continue her greatness and get that slow American GFS on the bandwagon...this things going from DC to Boston to Maine!

E.H. Boston said...

I read in EasternWx that the 0z GFS and NAM were lacking some measurements...

Could be the reason for little change from the 18z runs???

0z UKMET is HOT TONIGHT!!! ~Randy, American Idol

Mr.B said...

Euro on board? It's all down to Tomorrow. Will the NAM win again???

E.H. Boston said...

EURO was on board big time this a MA hit, Boston, we'll have to wait to see what it says tomorrow and the 12z GFS tomorrow will be huge.

Lets get this storm in here, BOS, by Tuesday night and wrap up by Wed PM...then I am off to ITALY for 10 DAYS!!!!!


Novatriguy said...

Did someone forget to wake up the GFS this morning? The 6z looks like the "same ol, same ol" - out to sea!

Novatriguy said...

That was my first post. Been watching you guys/gals banter over the past 2 years. Finally got the nerve to jump into the fray. I'm an Accuweather Proffessional refugee. Could not justify paying $24 per month.

Foot's Forecast said...

Welcome aboard novatriguy! Yes the good ole GFS once again forget to have it's early mornng coffee. After that JAVA kicks in, perhaps the 12z run will be more exciting. If it comes in swinging, that will be the checkered flag and the Winter Storm Watch race will begin later today.

Hope you've enjoyed our banter. It's great to chat with nice people who don't rip each other apart with every post like what some do on OTHER weather discussion boards that will remain nameless at this time, such as EasternUSWx. (Oops, sorry that slipped!)

Can you give us an idea of where you are generally located. Helps when we do a roundup of storm observations.

To everyone...I'll be out and about gardening this morning. Sike, you know what I'll be doing! Battening down the hatches.. checking the snowblower for the first time this century, clearing the yard of children debris and other storm preparations. So don't get in a dither if there's no response from me for a few hours.

We'll start a new round of comments this afternoon or tonight with a new post once we see all the models trending together.

Also..I'll wrap up the cold contest and post results before the storm. In addition, I'm going to do a short post on what useful storm prep tips we can offer each other. Everyone please consider sharing your knowledge of how to best enjoy a big storm be adequately prepared at the same time (ie in the event this becomes a SuperKahuna..20"+) I have definitely learned from the Feb 03 storm and will not exhaust myself again like that. This time, I'm ready baby, so bring it!

Mr.B said...

LOL, anyone see the DGEX this morning. All out massive destruction. 10+"

Novatriguy said...

I'm located in Loudoun County VA - the land of 2 different weather affecting regions. It could be snowing in Roundhill and raining in Ashburn but don't worry kids schools are closed. My wife, who is also a public school teacher, loves it. I think Loudoun has the most alloted snow days out of all the DC Metro Counties.

WEYTYN said...

Hey Chip- thanks for the offer on the 10 page fax. but keep it for yourself you may need it.
I was able to find some poison ivy leaves out under the pine trees nearby. I am good now till next SAT.

terpguy said...

Well, after waiting about 5 minutes, I finally got HPC to load..I guess the whole country is trying to log on.

If they verify, it looks like my area will get plus or minus 0.8"of liquid. Even at 6 to 1, I'll take it!! With cold, it will most likely be higher.

If this puppy turns north....who knows!

Mr.B said...

Hello GFS!!!! Big time EC storm!!! 10+"

Mr.B said...

WOW!!! 1.75" of liquid for almost all of MD, and it clips me as well. WOAHO!Can you say 20"

Foot's Forecast said...

I'm back for a few min. Mr. B where are you seeing the 1.75? That would be confirming my greatest fear...24" and a PDII repeat.

Evan said...

GFS 12z has 1.5-1.75 qpf for all of maryland!!

Mr.B said...

Mr. Foot

Sorry it''s the GFS. The GGEM could spell trouble?

Julee said...

To prepare for the President's Day Blizzard of year's past, I bought several boxes of Carnation *powdered milk* (hoping I'd never have to use them). Powdered milk? Eck!
Turns out I DID have to use them and the milk wasn't bad. Good enough for cereal, cocoa, and cooking. Now I always have some on hand. Shelf life is about a year.

Will we have something like a President's Day Blizzard this year, Mr. Foot?

Foot's Forecast said...

The PD III storm is currently classified top secret in the interests of national security.

The FBI has already begun regular patrols of your property in unmarked cars, in case you were wondering about the black tinted window vehicles parked out front.

If you are exposed as the source of this material, the secretary will disavow all knowledge of your activities.

This message self-destructs in 5..4..3..2..

Julee said...

Get me Jack Bauer on the phone!

E.H. Boston said...

This is definitely starting to get the hype of the century. Tons of servers down and people's hopes rising by the second!

How many would be jumping off the Tobin here and Boston, into the Hudson in NYC, and into the Potomac in DC if this storm didn't deliver??

Peoples hopes are SKY HIGH!

Desperate said...

I fear for my mental well-being if this storm does not pan out Tuesday.
I just can't stand this snowless winter much longer. I need many snow days. One is not enough.

Foot's Forecast said...

E.H. please note I am definitely not hyping the storm for your region. I have merely brought NYC/BOS into the fray for accumulating snow (say up to 6" for now) but not as an all-out blizzard, despite what the models show.


MARCH 2001..THE ULTIMATE sNOwstorm (although some areas along the Jersey and DelMarVa did get hefty snows, was confined to eastern counties if memory serves correctly.

The potential is there for NYC to BOS but I'm not buying right into it yet. Main targets remain Mid-Atlantic, and not because I'm trying to selfcast the storm. Just following recent HPC guidance.

Comments by Larry Cosgrove indicate there is a chance this goes all out but we have 24+ hours more of model runs to see if there are hints of this. In March 2001, everyone was calling for 12-24" + up and down I-95, then 12-18 hours prior to the storm,the modeling (and the storm) completely fell apart. I don't think that will happen given the strong pressure gradients and temps this time, but we have to guard against leaning too close to the B word. I'm not there yet, but if I do go there, you'll know!

Desperate said...

Thank you for boosting my hopes, Mr. Foot. You're getting me through the next few days with your optimism.

Foot's Forecast said...

This shouldn't totally bust like March 01 because that was going to be one of those "and it explodes along the coast..." storms of which I am always skeptical. In fact I challenge anyone to find the word "explosive" anywhere in my forecast for this storm. This will be steady snowmaker that might POP at the end, but will generally deliver 12"+ to the I-95 cities and interior. I'll let all the model mayhem keep mayheming rest of today and tonight, then revisit all this tomorrow and see where we stand.

TQ said...

With all the talk about QPF...keep in mind that it/s probably the worst variable forecast by the use with caution.

That said...there's more to quantitative snowfall forecasting than multiplying liquid by 10. Temperatures in the cloud/s 'crystal factory' with arctic air masses are much colder than they are in polar air masses. The colder cloud temperatures produce snow flakes (stellar dendrites) with a high fluff factor that have a snow-to- water ratio around 20:1. These snows are poor for building forts...snow people...and snow balls but make for great skiing and sledding.

As for forecast trends; the influence exerted on the surface LOW by the upper LOW over the Great Lakes and when the fresh batch of arctic air makes it E of the mountains appear to be the key elements at this time. Now that the upper level system is over land where it can be better sampled by the rawindsonde network, the progs should begin to converge toward a consensus.

Foot's Forecast said...

Very good points tq and well taken.

Please note I do not take QPF verbatim, I use it as a guide and do my own calculations with that fluff factor into account. This was especially the case for Feb 03 (18 F and snowing heavily in Dundalk, along with everywhere else) and the small incident on Wednesday.

I did some research a few weeks back on the snow ratios and discovered there is some theories which suggest the actual ratios are closer to 13:1

Despite what everyone is saying about WAA (Warm Air Advection) I still believe that High is going to wedge down over the Mid Alantic more than we anticipate, the cold air ultimately enhancing snowfall totals as you aptly explained.

I saw that Elliott Abrams is coming out with some statement. Having listened to him for 25+ years, he does not often say "Could Be A Big One"

Will be an interesting 48 hours to go. Thanks again for posting your expertise.

Mr. Foot

Foot's Forecast said...

Let me add "fluff factor or lack thereof"

If I believe mixing will occur or a changeover, I usually go with 8 or 6 as terpguy mentioned.

Don't think northern Balto County would see a 6:1 ratio though.

Evening family program I'll look things over and post an update at the usual time...after 9 before 11.

TQ said...

Mr. Foot sez...
"Despite what everyone is saying about WAA (Warm Air Advection) I still believe that High is going to wedge down over the Mid Alantic more than we anticipate, the cold air ultimately enhancing snowfall totals as you aptly explained."

I agree. The models...especially the lower-resolution medium range (MR) like the GFS and European... are notorously poor at resolving the southern extent of arctic air massess. I think one can get a better feel for boundary/s position by the lifted index gradient.

Whether the arctic air spills out of the Piedmont into VA/s coastal plain remains to be seen. The LI forecast from the short range ensembles suggests it could.


PS - My remarks and cautions about QPF were addressed more toward your readers...some of whom may not have been aware of its limitations.

Foot's Forecast said...

Understood about the QPF. Interesting you bring up the Piedmont, unless I have missed it in all the HPC discussions, I have not seen any talk of cold air damming. Am I off base or does it appear most NWS offices in the region are discounting this could occur?

Andy, Southern York County PA said...

Hopefully this will verify. 20 inch snowfall would be so sweet! Many mets at accuweather are on board. HM there is in blizzard mode. Time will tell.

terpguy said...

Mr. Foot-

What happend to that chatroom that your student set up?

Great graphic...let's see if this comes to fruition. I've seen nothing of CAD in any discussion. My feelings of like many others: the models are all over the place, and no agency can disern a clear pattern.....yet.

I'll keep you posted on the Great White North (of Maryland)

terpguy said...

Chat room is open.

Don't ask me how I got it. I was zooming around and it appeared on one of my screens.......??

TQ said...

AKQ/s afternoon disco had CAD...altho unless the extension of arctic HIGH hangs a right (like last night/s GooFuS) and oozes down down I-95...all you have is an in-situ cold wedge re-enforced by the rain.

CAD is often mis-diagnosed. It/s more than just some isobars nosing SW along the mountains.

TQ said...

Tonight/s Eta / NAM / WRF shows some wedging from the eastern extension of the parent arctic HIGH over south-central Canada; however it also shows the surface LOW heading up the OH river valley and a secondary developing of the coast of the Carolinas.

Just amazing how the short range model solutions contrast with 'promises' made by the medium range.

B said...

concerning your new map posted, how come there is a huge cut off in the DC area? Is DC really going to miss out now? -- if so, why? what happened?

E.H. Boston said...

All this hype is starting to take away from the storm. For me, anyway, its still 80 hours away...thats eons of time for this thing to go haywire.

DC...I feel your pain. HM on Accuweather is calling for 12" in DC, don't fret. He's calling for 12" in Boston too and 12-18" in Hartford and NYC.

Not bad.

B said...

12+ inches i'll be happy with. In fact, normally i would be happy with 6inches, but due to the hype im greedy now. Plus ive told all my friends that we're going to have a snowday tuesday. -- still think we will too. But a blizzard with 2 feet of snow is always nice, we'll see....

DerbsATerp said...

Mr. Foot,

Ive been watching these prediction since their conception a couple of weeks ago, and I'm down here in College Park, hoping for a really big snowstorm to make my senior (final!) year a great one, and I was wondering what you thought what this storm was going to do down here in good ol' College Park. Please let me know, I would really appreciate it, as would many of your faithful Terrapin readers (at least after the MD-Duke game tomorrow).

Foot's Forecast said...

Look you hypesters...

This is not a case of "Foot's predicting a blizzard!"

Which the kids loved to do back in 03 AFTER the actual storm occurred. They would just start doing that in the hall to get people talking when there was no storm in existence anywhere in the US. They figured after the Feb 03 storm, every time I made a forecast it would turn out to be a blizzard.

It is way too early to even discuss the B-word, and mostly because that does not mean a lot of snow, it has much more to do with visibility and windspeed.

Heck the term "heavy snow" sounds more ominous than it really is:
4 or more inches of snow in a 12 hour period. Think about steady state would be 1/3 of an inch an hour. I would say the people in Oswego feel THEY have heavy snow.

I put the map there to get your attention, but also to serve as a discussion we really think it will be this extensive? Does that represent the models overdoing something, or is the model underdoing it?

You tell me if that map is wishcasting or portending a very difficult week ahead.

terpguy said...

I see a map that shows a difference of 35-38 miles between >1" (AA Co) to 18"+ (Hereford).

Tight call...tight call!

Mr.B said...

I think I might faint!

TQ said...

If that map is from the 18z run...then it needs a large grain o' salt next to it.

The off-hour runs are flaky to the max so much so I don/t even look at them.

In other news...despite the Eta's 'wet blanket' forecast tonight...the GFS is showing some continuity wrt snow for the M-A (eastern extension of arctic HIGH arriving ahead of LOW), incorporating the trend toward secondary development off the Carolinas, and the the European/s idea of a bomb going off near the 40N / 70W 'benchmark' on Wednesday.

Since two streams are involved -- polar and sub-tropical -- knowledges of how those features evolve are needed for the forecast to be successfully solved.

wvmommyof4 said...

My only fear is that if this storm keeps moving north each time new info comes out.... Will it do just that and move too far north for the dc/baltimore/west virginia area to feel the bulk of the storm. To be honest the media hype scares me. It is so much better when they have not caught on. I guess it has just been far too long to have gone without substantial snow. This of course is anything over 3 or 4 inches haha

Mr.B said...
This comment has been removed by the author.
Mr.B said...

Winter Storm Watches are up. Alright. First time this year.

E.H. Boston said...

Local mets up here are pretty much now calling for

Blizzard Conditions
Heavy Snow
Strong Winds NE..up to 50+ mph
Coastal Flooding

1-2 FEET of snow

YAY...I am going to be stranded at Logan Wednesday night!!!!

Novatriguy said...

Accuweather has an accumulation map(Mon - Tues) under their main headline story but non-clickable. It's hard to tell but looks likes we are all in the 3-6 inch range up to the time frame specified (except for anything north of CNJ).
EA has post from around 4am with some worry about too much of a northerly track although late night GFS has us in the all snow zone.

Novatriguy said...

What's with the Nexlab models? They are still stuck on the Saturday 6Z issuance.

Foot's Forecast said...

Good morning everyone, and lookey what we have here. I was wondering to myself late last night if WSW's would go up today or tonight. I thought since the actual storm period wouldn't be until Tuesday, they might wait until this evening.

Now it appears the final product will be bigger, and that might be the reason the NWS is launches Watches now to alert the public.

Andy, Southern York County PA said...

Wow! Been reading some of the propaganada about this storm. HM from accuweather does a good job in laying out what the models mean and what the storm could do. He indicates a CAT 5 blizzard seems in the making. This could be an ULTRA ULTRA KAHUNA. Let's hope it verifies becasuse we all deserve a monster after the most recent anemic winters. He did also mention wind gust of 40-60 MPH.