Wednesday, February 17, 2016

So you've heard...

RECAP OF THE PRESIDENTIAL POWDER STORM
AND PRELIMINARY DETAILS ON NEXT WEEK

Day 7 Surface Projection from the NOAA Weather Prediction Center

6:30 PM EST 2/17 - RECAP & LESSONS LEARNED FROM THE MONDAY 2/15 EVENT
By Southern Maryland / Capital Region Forecaster Jason Mitchell

SUMMARY This year's President's Day snow/ice storm for parts of the southern Mid-Atlantic exceeded the expectations of many forecasters, including some of us here at Foots. For our readers in Southern Maryland, the team presents this outline of factors that led to some areas receiving much higher totals than the 1-3 inches that was expected.

1. The snow started several hours ahead of schedule, with most locations seeing snow prior to midnight Sunday night. Due to the extremely dry airmass in place, the thinking was that it would take some time for the airmass to moisten. However, the moisture surge in the low and mid levels of the atmosphere was strong enough to overcome the dry surface air faster than expected.
2. During the overnight hours Sunday night, snowfall bands become heavily concentrated right over this area, while areas to the north over DC and to the south in Virginia saw less snow.  
While the initial expectation was for snow to begin by 3-4AM and continue through early afternoon, the combination of the earlier arrival and heavier bands overnight allowed snow to accumulate much faster.

3. Snow-to-liquid ratios in this storm were reported to be around 20:1, whereas the standard is usually 10:1. This means that had we seen the liquid equivalent of 1 inch of rain between Sunday night and late Monday morning, we would have had 20 inches of snow.  
Due to the dry airmass and well below freezing temperatures, high ratios were expected (closer to 15:1), but not quite this high.

CONCLUSION: All three of these factors accounted for an extra 3-5 inches of snow. What was also remarkable was Part 2 of the storm. 
  • Computer models indicated for days that we would see a significant dose of rain and much warmer temperatures following the initial round of snow and ice. 
  • Not since December 2009 have we seen a significant snow depth disappear that quickly. And to think this all happened after we had subfreezing temperatures for 120-130 consecutive hours is very noteworthy.
LOOKING AHEAD: Heading into the long range, computer models suggest that it may not be safe to say this was our last accumulating snowfall event of the winter. Whether there will be enough cold air in place remains to be seen, but it looks like El Nino is not done yet with bringing significant moisture-laden storms to the region. 


Day 6-7 NOAA Liquid Projections: The last time you saw a map like this? 
That's right... last month.


Indeed the period next Wednesday 2/24 to Friday 2/26 is looking more significant with time and may be taking on aspects of both recent and memorable storms of the past. 

To receive on-going reports by app, text and email on this next potential winter weather event, we invite you to consider joining the Powderhound Insiders. We hope to see you on board there soon!



36 comments:

Westsidehideaway said...

Well, Well, Well. Another possible Big One to watch out for! One week out and lots of weather models to ponder. This will be fun!!

NeedaSnowday said...

Hey Westside... The euro looks juicy, again.... But it's still a week away! Fun to track though!!

Westsidehideaway said...

Yes Needasnowday. Very juicy indeed.

Julee said...

Isn't it sad that winter's almost over?
Do we have fun like this in the summer, anticipating a big storm? NO!
Big summer storms just mean hot, humid, wet inconvenience. Big WINTER storms
are full of anticipation -- planning comfort food meals, creating toasty drinks, gathering around a roaring computer to discuss events, fun in the snow, closed work environments and, okay, shoveling.
One more time Winter?

Butch Dynomite said...

Oh yeah ... Love it ... I hope to be on the cold side if it comes.

Carrie said...

You are so right, Julee! Love winter storms and hoping for one more good one!

BioPat said...

I love winter storms as well and the quest to identify the major storms is such a challenge. Having the opportunity to chat/blog with all the Foot's friends is so much fun I really look forward to any major weather event where we can discuss the possibilities.
Well before December we knew winter would be on a late arrival and the time frame for major events was initially after Jan 10th with Jan 20th - March 2 as the most significant time frame. Needless to say the forecast was spot on for the major events. So if we can squeeze one more event in to this winter so be it! Just love online chats with the Foot's gang of regulars and even the newbies have added to our banter.
An aside, I am home recovering from the MOHS surgery. All went well got clean margins on the first go around and now just working on the healing process. Julee hope your healing process is progressing well and come spring you'll be able to find the warmth very healing.

Kathi said...

As a motorcycle rider I am definitely looking forward to spring but as a snow lover I would love to see one more storm before winter ends. I don't comment a lot but always enjoy coming here and reading everyone's posts and learning from all of you!

BioPat, so glad your procedure went well and you got clean margins the first time. I had the MOHS surgery a couple of years ago on my nose and was very lucky that they got everything the first time as well. I'm sure it was all the riding I did without wearing sunscreen so I definitely learned my lesson.

Looking forward to what's going to happen next week and maybe after!

Unknown said...

Great news Pat!

MF said...

Next week isn't looking too good :-(

Tina said...

MF, it's alllll about perspective!!! I moved back to lower DE 3 years ago, but enjoyed the blizzards (and had my bacon saved more than once by Andy's, literally, to the hour predictions) over yonder, for years. BP, glad your edges were clear.... mine were as well, a year or so ago (but, then, my doctor used an ice cream scoop....sheesh). Julee, I'm still trying to figure out how you got around with TWO fractures in your hip...

We've had very little snow thus far over here... hoping next week changes that. I've also read there's a "possibility" in early March as well! It wouldn't stick around long, but the fun of anticipation could continue just a little longer!!

ravensbbr said...

(Duh-nant. Duh-nant. Dunt-dunt-dunt-dunt...)

http://www.accuweather.com/en/weather-news/cold-air-snow-storm-potential-may-return-to-eastern-us-next-week/55464260

Long way to go but... :-D

Unknown said...

So what does it mean? another three feet?

Unknown said...

Ground control to Major Tom. Take your Manwich and put your powderhound jacket on. Commencing countdown, engines on. Check ignition and may God's love be with you.

This is Ground Control to Major Tom
Do you really see a storm
The papers want to know how much snow will fall
Now it's time to leave the capsule if you dare
"This is Major Tom to Ground Control
I'm stepping through the door
And I see the storm moving in a most peculiar way
And the stars look very different today
For here
Am I sitting in a tin can
Far above the world
Maryland will be white
And there's nothing I can do


Though I'm past one hundred thousand miles
I'm feeling very confident
And I think my computer model runs know which way the storm will go
Tell my wife I would want her to shovel the driveway she knows
Ground Control to Major Tom
Your circuit's dead, there's something wrong
Can you hear me, Major Tom?
Can you hear me, Major Tom?
Can you hear me, Major Tom?
Can you "Here am I floating round my tin can
Far above the Storm.
The Mid Atlantic is doomed
And there's nothing I can do."


IN HONOR OF DAVID BOWIE---THIS IS HIS STORM

ravensbbr said...

Given the large amount of moisture forecast and potential for fairly cold air to be present, Brent, it's a relatively good chance something could happen, just too far out as to say exact amounts of anything. The potential for something major is there, but at this point it's more of a "be on the lookout" than a "sky is falling" situation. Let's say it looks better than, say, an average week in July would, hence the excitement. :)

Good work, Mike. Just finished re watching the Martian the other night, forgot there's a DB montage clip in there as well.

Morpheus said...

Lots-O-water coming our way, too soon to tell track and all, but I just have this feeling that us lowlanders will be signing in the rain. Felt that way with the last one as well and we got a good dose of snow so I am just going to be pessimistic and guilt this storm out to sea just a bit.

Westsidehideaway said...

Mike. Love the connection to Bowie. Gotta start stacking the wood just in case.

BioPat said...

Great job Mike! I hope you're still singing the same tune in the next 4 days as well.

I'm certainly no where as talented as you but this storm is something worth watching. Cold is scheduled to return but will we be seeing the white stuff or just a few days of lots of cold rain.

Andy, Southern York County Pa said...

I have been more absent than cash in a Kanye West Bank account as of late. I have not been on a private computer for two weeks save for some quick online glances from my mobile phone and token posts. Bottom line is next week will not feature another Ultra Kahuna. What is on the table is a possible wet snow event with the upside of accumulations up to 10 inches around central Maryland. If all the ingredients come together just right I think that is our high end event. There are many moving parts and pieces of energy. How these amplify, and interact will determine what happens. Right now there is potential for a nice snowstorm but also potential for a small mixed winter weather advisory or less system. My bar is set at 0 to 10 inches. As we come closer things will come more into focus. With a complex system like this at this range I think all we can do is focus on probabilities and set a baseline.

ravensbbr said...

Breaking news: Dow Jones Weather Average drops 200 points on first actual non-Kahuna-esque bear market forecast in living memory from Andy. Snow shovels given away on street corners. Manwich goes bankrupt from oversupply. Unprecedented.

Kidding, Andy, we all love ya, just giving you a hard time after all those (mostly) correct bull market pro-snow powderhound forecasts. Credit where credit is due, I just sit out here, venture a nowcasting guess time to time and make snarky comments that only I find funny, but it takes guts to make an actual call, and my hat's off to you, the Foot's crew and the other folks with met backgrounds. :)

Rufus said...

Pat glad everything went well. Julee how ya doing?

BioPat said...

Andy thanks for your first call on next week's event. The sun angle is changing so providing the temperatures for a dry snow decrease every day. A wet, heavy snow, or very cold rain will more than likely emerge; 0 - 10 is a broad range but still too far out at this time of year.

Morpheus said...

My first call (for east of 95 AKA the "lowlands") Rain, lots of rain and more rain. Maybe a bit of evening snow to wrap things up, with little to no accumulation. Would be great if this was wrong but not likely. Maybe the highlanders will have more luck.

Tracy Eitner said...

Yes, yes, make it rain! No more snow! Gotta represent the PowderHaters out there!

Bring on the heat! 123 days until Summer!

Snowplease said...

Let it snow that's all I have to say if you hate it then move south or get over it cause we have some good chances through March!

Tracy Eitner said...
This comment has been removed by the author.
Morpheus said...

No snow hater here, just a realist for those of us at low elevation. This storm potential is looking more wet than white across the board but the picture should be clearer by Sunday.

Tracy Eitner said...
This comment has been removed by the author.
Tracy Eitner said...

When it gets hot in the Summer and y'all complain, can I just say "move to the Southern Hemisphere, it's cold there now!"?

Or do I just let you have your opinion with out the rude and nasty comment.....

Snowplease said...

I was not talking about you Morpheus I think your right the low landers will definitely be on line as usual while Andy and moutain men cash in lol. Still think everyone could get another decent storm but as usual time will tell.

Butch Dynomite said...

Hope springs eternal in the human breast;
Man never is, but always to be blessed:
The soul, uneasy and confined from home,
Rests and expatiates in a life to come. Alexander Pope

My English teacher used to say the first line when I asked if he thought I would get a good grade on the upcoming report card... He was a good teacher .... But I thought of his quip as we fixate

Butch Dynomite said...

"So you're telling me there's a chance!!!!"

-Loyd Christmas

ilv2fly said...

Hi Tracy, for me, if it's cold outside there should be purpose and therefore snow. But, I am definitely with you looking forward to green grass, flowers, and driving with the top down.

Westsidehideaway said...

It's February. Let it Snow!!

MF said...

I agree. If it is cold, there should be snow.

BioPat said...

Well folks, looks like we are in for a few ugly February days of cold, cold rain. The temperatures may provide a mix of sleet and sometimes a wet big flake snow but overall just that winter rain that we all find a wast of winter liquid.