Wednesday, February 20, 2008

ALMOST DE JA VU ALL OVER AGAIN

WED 5:00 PM. I personally was glad not to see an early dismissal, as today might have been the only day this week I see my Environmental Science students. With interim quarter grades due Friday, I knew it be their last chance to lock in the grade they want. They all knew why, as the word has gotten around about Friday's storm. But then you should have seen the look on their face when I mentioned what's brewing for NEXT week! The next 10 days could turn out to be among the most exciting periods of winter weather of the decade. "What would cause that to happen?" they wondered. "Oh nothing big, really, just a massive hemispheric trough extending from the Arctic circle to the Gulf of Mexico, with a possible stalled cutoff Low parked over the East Coast..for a day or two. Kinda like March 1993. That's all. Okay, now back to the assignment that's due by the end of class." :::stunned silence deer in headlights::: Needless to say, they were motivated to get the work done.
WED EVENING DISCLAIMER: Note that at the end of class I showed them via the internet these were not my original ideas, but that of two different forecasters whom report on long range trends. I'd never have enough expertise to create that kind of dream scenario on my own...and end up being right.


DELAYS ON THURSDAY MORNING? Difficult to predict this early, depends a lot on how much more falls, if there is rapid refreezing overnight. I would definitely set the alarm, and just be pleasantly surprised (or annoyed) if there is one.

THURSDAY NIGHT-FRIDAY: There are no major changes except to make it clear I expect more ice than snow due to cold air damming at the surface. This high probability of frozen precipitation and it's arrival overnight into Friday morning makes the closing of schools and colleges a near slam dunk. A roundup of what the evening forecasters are saying will be very interesting to see, I expect a wide range of ideas.


WED 6:00 AM. With a snow advisory posted for central and western Maryland, NWS ideas on the clipper arriving this afternoon are now coming around to what has been discussed here for several days. The general thinking on this first round has been that it will be light and intermittent, and not enough to prompt early dismissal of schools. However, this is also a case of De Ja Vu all over again, because those were the original ideas on the Dec 5 "Little Storm That Could." So what's the likely situation this time? Given a reasonable radar presentation, and the fact a slightly warmer atmosphere can provide additional moisture, we cannot rule out a one hour early dismissal for schools in the Baltimore Metro area. Of course, if you see the "blues" falling apart coming over the mountains, then game over. Those of you with access to comments, please continue to post your observations and any changes you detect in the forecast.

SPECIAL NOTE TO COACHES AND ATHLETIC DIRECTORS: Even without an early dismissal, the clipper's arrival time of 1 PM - 3PM does present the possibility that afternoon and evening activities will be cancelled.

74 comments:

terpguy said...

NWS
0458 local (DC/B'more)

AN ALBERTA CLIPPER WILL MOVE ACROSS THE REGION TODAY. A SNOW ADVISORY IS IN EFFECT FROM 11 AM THIS MORNING UNTIL 10 PM THIS EVENING. ONE TO TWO INCHES OF SNOW IS POSSIBLE ACROSS THE BALTIMORE AND WASHINGTON METRO AREAS. THIS WOULD MOST LIKELY IMPACT THE AFTERNOON AND EVENING RUSH HOUR.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

AN AREA OF LOW PRESSURE NEAR THE TEXAS GULF COAST AND ITS
ASSOCIATED WARM FRONT WILL TRACK NORTHEAST THURSDAY NIGHT AND
FRIDAY...AS A SECOND AREA OF LOW PRESSURE DEVELOPS OFF THE
CAROLINA COAST. THIS COMBINATION WILL BRING A WINTRY MIX THURSDAY
NIGHT THROUGH FRIDAY NIGHT. THIS INCLUDES THE POTENTIAL FOR
SIGNIFICANT AMOUNTS OF SNOW AND...OR ICE.


also..

...SNOW ADVISORY IN EFFECT FROM 11 AM THIS MORNING TO 10 PM EST
THIS EVENING...

SNOW IS EXPECTED TO REACH THE
WESTERN WASHINGTON AND BALTIMORE SUBURBS BY NOON...AND THE
WASHINGTON AND BALTIMORE METRO AREAS DURING THE EARLY AFTERNOON
BETWEEN 1PM AND 3PM. SNOW ACCUMULATIONS OF 1 TO 2 INCHES ARE
EXPECTED. HIGHEST SNOW ACCUMULATIONS WOULD BE ACROSS NORTHERN
MARYLAND ALONG THE PENNSYLVANIA BORDER. SNOW WILL COME TO AN END
THIS EVENING.


...and so it goes...

Grant said...

I sure hope we got one hour early dismissal

crazedsnowboarder said...

31 degrees Fahrenheit here in the Hereford zone wind NE at 5 mph. Will let you guys know when the snow starts up.

photofreak65 said...

nothing here yet in Hydes. 30 degrees.

photofreak65 said...

It's Snowing Here!!!!!!!

crazedsnowboarder said...

snowing here

Karl said...

Howard has canxed all after school and evening acty

photofreak65 said...

I've got a light dusting here so far. Only on the grass. Side walks & driveway still wet. But coming down at a good clip

I'm in Hydes

terpguy said...

1550 local-

Harford County cancels all evening activities.

27.9°F and steady light snow. Covering grassy areas and just starting to stick to pavement.

terpguy said...

Fallston.

sorry...

emsays said...

As far as the next storm goes, WJZ says there is a chance the snow will turn over to rain, because the warm air will move in to our region. Do we think this will happen?

essexdancemom said...

Mr. Foot,

Justin Berk has been speculating on the effects of the full moon and lunar eclipse of these types of storms. Any thoughts?

Began snowing here at 12:30. Grass is covered but sidewalks and streets are wet.

Kyle said...

Thanks for answering my questions earlier (about PNA, etc.). Sticking to grass and cars here in Odenton/Ft. Meade, but only wet on pavement. It seems like it's taking too long to get going for there to be a repeat of the Dec. storm. As for warm air moving in, I've read just the opposite, any updates to prove otherwise? Thanks.

snow lover said...

Snowing good here and 29.1 degrees. Durring sixth and seventh period the snow was really combing down. We are in the stormy weather now:):)

Mr. Foot said...

Afternoon all. 31 and light snow in Dundalk. Grass nicely covered, I would say about an inch. High fluff factor helping accums, indicating very cold air where these flakes are forming... the dendrites if I'm not mistaken, form at -15 F up there.

essexdancemom and emsays..WJZ has a bunch of nice people on their forecast team, and Bob Turk is a sweet man. And Mr. Bass is Mr. Bass, and we'll just leave it there. There are no widespread indications of warm air mixing in with this storm at the low levels, enough to change things over to rain. Once the Arctic air settles in later tonight and tomorrow, it will take until Saturday morning to get scoured out. True, warm air will intrude at upper levels, 5000ft+ but not at the surface. That's why NWS has sleet/freezing rain for majority of Friday.

I have read Justin Berk's ideas on eclipses, full moons during storms, but have not done any research on this. Though Julee I think did send me an email that Feb 20 is considered the "Snow Moon"

Remember my call for 4" is the total amount of frozen precip to fall from Wed noon to Friday night.

And so it begins.

snow lover said...

yes it does what we have been looking forward to for a week

Anonymous said...

Kudos Mr. Foot for once again nailing the forecast! Can always count on you.. and fortunately, I had a "snow date" for a meeting orginally scheduled for tonight! :)

Mr. Foot said...

Having dinner now, be back later, say after 7PM. (We eat a lot here before big storms.)

Kyle said...

....you can add another 'deer in headlights'! Are you serious about next week?! I can hardly contain myself! I know that it's far away and things can change, but just the prospect of something like that is very exciting. Also, I noticed that the PNA has seemed to level a bit, but the NAO never trended negative, rather is trending positive. Is that going to have a negative affect on us?

Anonymous said...

>gulp< uhh...next week!? kinda like March 93.. seriously?? Spring sports start March 1st :::whining::: Did you mention this to your AD!?

snow lover said...

I was born in the June of 93 so I have no clue what that month was like besides the storm of the century. Please fill me in on that month.

snow lover said...

can some one give me a little history lesson on the 93 blizzard????

Mr. Foot said...

March 1993 Superstorm... known as the Storm of the Century.

http://en.wikipedia.org/wiki/Storm_of_the_Century_(1993)

Enjoy!

Not saying it will happen, just that major computer model "averages" are pointing to the potential for an extremely significant event next week.

Prospero said...

Maybe it was bad here - I was still at Penn State.

In terms of big storms for Penn State, I don't think anything could beat January 1996. Were you there, Mr. Foot? It was the final semester of my undergrad years. I had friends trapped at the Harrisburg Farm Show Complex for a week!

Mr. B said...

Had about an inch here toady.

Models not looking as good as yesterday, but the new Euro did. I expect 0ZGFS to play towards the Euro. Colder/wetter. Let's hope.

Mr. Foot said...

Then again, I guess the potential is increasing.

How often do you think the NWS sends out airplane reconnaissance in middle of the winter to investigate a Pacific Storm that is expected to affect the US?

Read this, then ponder on the significance of it as it relates to what may be coming next week.

from HPC
OF THESE INDIVIDUAL SYSTEMS...ONE
SIGNIFICANT SRN STREAM PAC STORM AND ASSOCIATED ORGANIZED
RAIN/WINTER PCPN FOCUS HEADING INLAND SEEMS ON TRACK TO REACH THE
US WEST COAST SUN...THE CENTRAL US MON...AND THEN POTENTIALLY
PHASE IN ADDITIONAL NRN STREAM ENERGY/COOLING OVER THE E-CENTRAL
TO ERN US TUE/WED AS PER SIGNIFICANT PATTERN AMPLIFICATION.

A WINTER STORM RECON FLIGHT HAS BEEN SCHEDULED OUT OF PORTLAND FOR
USE IN TONIGHTS UPCOMING 00 UTC NCEP MODEL SUITE IN AN EFFORT TO
GAIN ADDITIONAL PRECURSOR ATMOSPHERIC DATA FOR THIS SYSTEM THAT MAY LEAD TO DECREASED FORECAST ERROR.

Mr. Foot said...

If you know what that means, then you can follow with words like, "Holy crap." or other colorful metaphors.

TQ said...

"...the dendrites if I'm not mistaken, form at -15 F up there."

Stellar dendrites prefer temperatures between -12°C and -17°C.

Snowfake Morphology:
http://www.its.caltech.edu/~atomic/snowcrystals/primer/morphologydiagram.jpg

Snowflake Guide:
http://www.its.caltech.edu/~atomic/snowcrystals/class/class.htm

Kyle said...

H O L Y C R A P !

snow lover said...

mr foot I have looked at that but was wondering what the forecasting was like for you. And i might be wrong but didn't the storm in 93 come from the gulf?? What did that messer mean I don't understand but am getting excited!!!!

snow lover said...

And still snowing good here

Kyle said...

Hmmm...looks like the clipper is dissipating pretty quickly. That's too bad.

Prospero said...

That's the nature of a clipper storm.

Still looking forward to tomorrow night, Friday (and Saturday).

snow lover said...

anyone want to answer my questions and that one word is message not messer

Kyle said...

Sorry snow lover, I'll let someone who's smarter answer that. Something odd though: The US Hazards Assessment took off the threat of ice for us on 22 Feb. Does this mean less ice = more snow, or does this mean less precip altogether?

snow lover said...

I think more snow cuz we all know precip is combing

thnx anyway

Mr. M. said...

Funny...if I heard Channel 11 correctly, they are calling for temps to reach the 50s next week.

Kyle said...

It would make sense to have a dramatic warm up before a large storm. Kinda like this week, perhaps.

snow lover said...

the warmer before the better that means more instability in the atmosphere and a larger collision of air masses..someone please attempt to answer my questions

Mr. Foot said...

snow lover et al.. I am going into the bedtime routine with my girls, will be out of commission until 8:45 at earliest. Will answer some Q's then.

Thanks TQ, meant -15 C not F!

mkgerst said...

I'll take a stab at what the message meant. I think it means that they want to check out the severity of the storm in the Pacific similarly to the way they scout hurricanes in the summer time (to collect wind speed, barometric pressure, etc.). That will help them to gauge the intensity of the storm and possibly help to predict precip amounts. That's my guess anyway.

As for the 1993 storm, I was 13 and I remember having off school for over a week. I lived in South Central PA at the time. We couldn't get out of our neighborhood for days. They had to bulldoze us out. I think we got something like 26 inches of snow.

snow lover said...

thnx and I looked at the radars and their is a little blip that is still creating snow here

Kyle said...

I'm wondering if this Portland flight is either 1) A new precedent that the NWS is starting for larger storms in winter in general (as in, it will become routine?) 2) The Storm of the Century was one of the most well forecasted storms in history and they want to make sure they do just as good or better with this one because it's 14 years later (better technology, etc.) and it would look really bad if they didn't see it coming or 3) This storm just looks extra impressive and they're taking all the precautions that they can (my favorite scenario).

Russ L said...

trying to get an idea for the thur. night & fri storm. if snow changes over to frz rain & sleet some time late fri. morn and continues through fri. night and early sat. morn---HOLY CRAP--that would be a lot of ice!!!! could that happen??

doublehelix454 said...

Well, it sounds like the Physics Olympics at Dulaney on Saturday is toast.

snow lover said...

kyle I am with you and am gonna really look at this one closely

Mr. B said...

Don't forget the eclipse starting right now!

Kyle said...

Thanks mr. b for the reminder! The one time that i'm glad that it's not snowing, go figure.

Mr. Foot said...

Clipper total: 1.8" in my yard.

Not bad considering we made the accumulation call 3 days ago.

What does everyone else have? Am wondering if that last batch that moves across Balto County dropped enough to push anyone over 2" ?

Thanks mkgerst for taking care of that question. You are exactly right about gathering of data. The other issue that I know TQ has pointed out in the past is that model projections for downstream systems can change drastically once the primary Low comes onshore along the west coast. This is because once a system crosses over land, real time land-based station data is fed into the computer model, providing a more realistic output. That is my layman's way of explaining it. I have also learned from other commentors on weather boards that HPC has sent these recon flights before, not a first time thing. It is probable this is done more than once a year. Apparently this was performed on the system which led to the V-tines storm of 07.

HPC is really holding the card close to the chest in their prelim extended. It seems to me they are purposely using vague and non-committal terms because they know members of the public read their comments. But if you can dissect their intent, they are concerned about a major event next week, just are not saying it in those exact words.

Yes I am photographing and videotaping the eclipse for class, it's in progress now and a beauty.
Julee was right...the Snow Moon.

ScienceGuy said...

The official word is that if schools in Baltimore County are closed or dismiss early on Friday, then the Physics Olympics event at Dulaney will be postponed until the snow date which is March 8th.

Aimee said...

Was the storm of 93 the one with all of the ice, or was that 96? I just remember being able to walk outside of my house in ice skates and skate around my street. That was awesome!

Chip said...

Very cool eclipse in progress, as Mr. Foot said, right NOW (9:24)! Didn't we have a total lunar eclipse at about 5:00 am a few months ago? Or was is more like a year or so?

snow lover said...

so does this mean that the storm nxt week will be big please show a GFS pic

Kyle said...

We maybe got 1/4 in. here, that's all. Only the grass is covered. At least with the high pressure and clear skies in place we are able to see the eclipse and help temps stay down. I'm willing to sacrifice the Thurs-Fri storm if it means The Big One will come next week. Regardless, if HPC decided it was worth sending a plane, then I think they believe something is truly brewing out there.

E.H. Boston said...

21z SREF and 00z NAM just eased my worries...sorry guys...you'll start as snow to ice, but will turn to rain...trend not looking good for you on this storm.

E.H. Boston said...

Snowlover, GFS doesn't have anything special, yet...patience is key in this kind of event.

Frankly, don't get your hopes up too high, too me this doesn't look as good as it did just 24 hours ago.

Anonymous said...

Ouch EH... bubbles are bursting everywhere!!

snow lover said...

yeah

Kyle said...

Wow...strike one, two and three all in the same day?? We've hardly even mentioned the dreaded 'r' word, yet it all of the sudden appears? The latest GFS looked pretty intriguing for next week still though.

snow lover said...

EH then why would they send a plane into it

Mr. Foot said...

EH is talking about the Thu night-Fri event.

I don't doubt it will change to rain...Friday afternoon. The arctic air that's rolling in tonight is going to take a while to dislodge, and not before a fair amount of precip runs over top to create a potentially serious ice storm again.

Our storm is just now developing over Louisiana as you can see on the radar.

Mr. Foot said...

Eclipse in totality! Look out the nearest window and up (unless you're in Lower Southern MD/Eastern Shore, getting another 2-4" sheesh.)

Mr. B said...

Nam please be wrong, thanks,

Russ L said...

mr. foot,
i agree, i think it is going to be very hard to warm up the surface temp's on friday. don't models have a hard time with CAD? if so,could be a BAD ice storm?

Chip said...

Very nice reddish-brown in totality from here in Parkville. So... inquiring minds want to know... should we back off on our hopes of sitting home and eating pancakes on Friday? (Say it ain't so!) :)

snow lover said...

We will be off precip coming thursday night and if it rains it will be late Friday not like 8 on the last storm. Delays tmmrw it is prettycold and roads are wet!!!

Kyle said...

hmmm, the updated NWS (1015pm) only mentions this: for next week so far:

"IT APPEARS ANOTHER LWX
SPLIT MAY OCCUR AS A VERY STRONG DEEPENING OF THE UPPER TROF OCCURS
OVER THE MS RIVER...PUSHING SEPARATE AREAS OF PRECIP NORTH AND SOUTH
OF THE AREA AND MORE UPSLOPE SNOW ACROSS THE MTNS FOR THE MIDDLE OF
NEXT WEEK"

Time will tell, as for tomorrow, I suppose a pretty big snow and ice storm is set to begin.

E.H. Boston said...

Russ, yes they do have a terrible time with CAD. I know that first hand here this winter. I wouldn't take the NAM verbatim, but I still think that this is trending north as these storms do every time this year, why would this be any different?

I'm usually getting hurt emotionally by these last minute northward spikes...being right on the edge to an icy mess.

Thats exactly what I think will happen with you guys. I think you are still in line for a 1-3" front end dump followed by hours of IP/ZR possible, before nudging 33F and turning to drizzle/rain sometime Friday night. Snow moves in THU night with temps in the mid 20's...no question, you will start as snow from DC northward. Just once you throw that warm air over top that dense cold air, then you have to worry about the PING PING and hopefully not GLAZE.

Mr. Foot, how much did you get with today's storm...inch or two? Your 4" accumulative call may pan out excellent.

Heck, WINTER STORM WATCHES are up for DC-BWI!!

Congrats.

E.H. Boston said...

Heck, looking at the 00z GFS...I'm calling it now,

I don't know how your news outlets do it...but scrolling at the bottom of the screen....

BALTIMORE PUBLIC
CLOSED

E.H. Boston said...

I'm referring to FRIDAY.

Kyle said...

Anyone know why the US Hazards Assessment took us off of an Ice event? Is it because we're already so close to the event? Also, any gut feelings as to sleet primarily or freezing rain? Sleet is just annoying to me, whereas freezing rain is downright scary.

Chris said...

I got 1.5" of snow in Hereford

TQ said...

Mr. Foot sez:
"...model projections for downstream systems can change drastically once the primary Low comes onshore...because...real time land-based station data is (available to initialize) the computer model, providing a more realistic output. That is my layman's way of explaining it."

Nicely done. May I amplify? That/s OK...no need to get up.

Without data from recon flights... the numerical wx prediction (NWP) models have only derived (vice measured) input from 'cloud track' wind vectors. No temperature data...no humidity data...no pressure data until the 'short wave' reaches land where it can be sampled / observed by rawindsondes (wx balloons with radio transmitters).

'Cloud track' wind vector data are better than nuttin' but nowhere near as good as having the 'feature' probed by a US government-issued wx balloon.

Recent advances in remote sensing technologies made it possible to probe distant...offshore storms with drones.

http://newxsfc.blogspot.com/2007/10/wx-drones.html

Mr. Foot said...

EH you terrified me there for a moment.. BCPS would not announce a closing this early. Admit that I quickly checked.

Folks, if we go in Friday, it will be a DISASTER. Remember Valentine's Week 07? There's going to have to be a HUGE northward trend in the models and scouring out this cold air significantly over the next 30 hours to have a surprise disappointment Fri AM. A weak disorganized area of LP in the Gulf of Mex/SE states isn't going to scour that cold air out fast enough, trust me. FRIDAY IS A SLAM DUNK.

Kyle, the US Hazards Map is a long range look ahead, the dates are printed at bottom left. They're now in the next period ahead, Feb 23 - Mar 8 I think. Once our large scale system for next week starts generating real data in the PAC NW, then you'll see indications of that storm appear on the Hazards Map I'll bet.

Heading to snoozeland now, not expecting a delay since I stayed up late getting all this done. I'll bet tomorrow night at this time I'm going to bed with the happy pink of a Winter Storm Warning though (or the dreaded Purple of an Ice Storm Warning)

Welcome to Big Kahuna # 1 of the 2008 Season. The fun begins.