Sunday, December 28, 2014

4 comments:
Journeying over the river or through the woods?

10:40 AM 12/28 - For those traveling hither and yon as the final week of 2014 opens, we offer a brief update to see if any snow awaits you at the next station. 

Highs Sunday and Monday should range from the upper 30s to the middle 40s for most of the Mid-Atlantic. On Tuesday, there's even a touch of powder possible for areas east of the I-81 corridor. After that, an approaching cold front will bring temperatures back below normal heading into New Year's celebrations. 





TODAY - Rain showers develop toward Noon, with a brief lull in mid-afternoon then resuming into the evening hours. Highs in the upper 40s with light West winds.


TONIGHT - Rainfall tapers off overnight, leaving overcast skies into the morning. Temperatures drop into the upper 30s under light Northwest winds around 5 mph. 

MONDAY - As the singer Sting once wrote, "Heavy Cloud, But No Rain." Thick morning cloud cover will eventually give way to a mix of clouds and sun with temps reaching the middle 40s. The most notable though subtle change will be that wind-- shifting to the North. This ushers in much cooler conditions from a large Polar air mass to dominate the country's weather the next few days. 

TUESDAY - Some computer models have been hinting at a touch of snow in the daytime hours. Available liquid is expected to be slight, but with Arctic air ruling from upper levels, any snow that falls will be rather fluffy and could easily accumulate, though amounts would be low. We'll keep watching this potential and let you know more on Monday.

Best wishes to all travelers if you are journeying back home before a shortened work week starts.


Thursday, December 25, 2014

No comments:
"How in the Dickens did Charles save Christmas?"

Welcoming you to our annual holiday tradition of celebrating the climate and cultural origins of our Christmastide festivities, each year featuring unique new twists we uncover in our research into the reasons behind the seasons.  

If you enjoy delving into the stories behind our holiday celebrations and would like to be part of an expanded effort for Christmas 2015, contact us at winter@footsforecast.org


A Currier & Ives Classic:"Winter Homestead" Circa 1867

9:00 AM 12/25 (Forecaster Foot) With a blaze of bright sunshine having returned to areas recently doused with a Blue Christmas Eve, we take a moment to share our favorite tale of the climate and historical connections behind our most cherished winter holidays. Most notably, we focus on why our society yearns more with each passing year to recapture a "Victorian-like Christmas." 

So grab the Peppermint Spice coffee creamer, relax in a warm corner, and enjoy this special story about why we dream for a White Christmas, and how many of the December 25-focused holiday traditions were influenced by a little red book conceived in the mind of a popular author who caught an idea walking the grimy streets of industrial London.

Saturday, December 20, 2014

3 comments:
No help from Dickens this Christmas

EARLY INDICATIONS FOR NEXT WEEK SHOW A MAJOR STORM -- OF RAIN -- 
TO IMPACT MOST OF THE EASTERN U.S. TUESDAY INTO WEDNESDAY

The famous "Frost Fairs" on the England's River Thames in the early 1800's. 
This is the winter setting a young Charles Dickens would have witnessed growing up in London. 

7:00 AM 12/20 - Won't it be an ironic twist of climate fate to have had a White Thanksgiving, then end up with a Blue Christmas? As a child, I would often be quite puzzled at why the atmosphere could so easily produce snow on almost every other day in December, except the 25th. Once during my teenage years, snow fell on November 11. Did it snow on 12/25? Nope! Instead, we had fog (in Philadelphia)

FABLED 5THs, JUST NOT 25THs In recent years, the Baltimore area had a string of snow dates with destiny we called the "Fabled December 5ths." From 2002 to 2009, measureable snow fell in that city at least four times right on the 5th of December. But alas, did that same weather pattern produce snowfall just 20 days later? Hardly! 

In fact, 2002 was the most recent observance of a White Christmas in Baltimore, according to official records from the Sterling VA National Weather Service. In fact, their data shows the elusive mantle of white is so rare that in 120 years of record-keeping, it has occurred just 12 times! This paltry underperformance of powder (for some cities) on the most popular date of the year might even drive some Powderhounds to cry HumbugJust once in recent memory along the I-95 corridor was present a Currier & Ives collection of snow by Christmas Day: In 2009, following the 20+ inch rout delivered by the 12/19-20 Blizzard. (Yes, we forecasted that one too ;-)

WHY ALL THE WHITE CHRISTMAS FUSS? Ever wondered whose idea was this, and why it launched a national perception-obsession to go dashing through the snow on a one-horse open sleigh? If so, look no further than an author known as Charles Dickens, and his last-ditch effort to generate some revenue in a downtrodden London market for writers. 

Wednesday, December 17, 2014

2 comments:
"Much Ado About Nothing?"
- Comedic play by Shakespeare, 1599

5:00 AM 12/17 - We've been holding that headline back from use for many years, because we knew a time would come that previous predictions might not come to fruition as originally thought.

Has such a time arrived? Does the liquid forecast map for Friday night through Sunday night shown have the "umpf" necessary for a significant coastal storm? Not really.  Lack of appreciable Arctic air, and an eroding presence of nearby snowcover, among other factors, has put the potential for a weekend storm "on ice" so to speak. 

However, there are lesser known details lurking for Sunday night that might surprise those who "check out" before the weekend thinking all is well with the forecast. ;-0

KEY POINTS FOR THE EASTERN WEEKEND EVENT:
  • While interior snow of several inches remains likely, the I-95 corridor should see periods of snow Saturday and Sunday. 
  • With rain mixing in at times Saturday afternoon, it now appears more probable that Powderhounds will need to act fast early Saturday AM in order to capture that fine moment when snow would be falling --- as Enya might say, "And Winter Came."
  • Sunday night may turn out to be the trickiest forecast period of this event, as delayed arrival will also translate to delayed departure. With cooler air filtering in from the north, rain could change back over to snow overnight into Monday. 
  • For teachers and students hoping to get an early break bonus, we're not certain the backwards pajama technique is reliable, but like any good science experiment, it's worth making multiple attempts (recording your data and evaluating the results)

Cover photo of Enya's 2008 Album, that has become
over the years one of our unofficial theme songs



Monday, December 15, 2014

4 comments:
"Do You See What I See...?"

DISRUPTIVE COASTAL WINTER STORM POSSIBLE FRIDAY TO SUNDAY. AREAS AFFECTED INCLUDE THE TENNESSEE VALLEY, CENTRAL/SOUTHERN APPALACHIANS & MID-ATLANTIC




  • Some computer models show the storm would move more quickly out to sea after crossing the Southeast, while others bring accumulating snow to the interior Mid-Atlantic and I-95 corridor.
  • Lack of large scale Arctic air should prevent the system from becoming high-impact, but travel and commerce will be affected Friday into Saturday for the eastern third of the U.S.


10:55 AM 12/16 - With festive times upon us, many "seasoned readers" are reminiscing about wintry Decembers of the recent past. Do you remember the exciting times 5 years ago this week, prior to the 12.19.2009 Big Kahuna that doused the Mid-Atlantic with 1-2 feet of snow? 

We know Powderhounds long for those classic "Currier & Ives" moments with trees sparkling from recently fallen snow and a mantle of white glistening in the night. Rest easy friends of the fluff, we have a long winter ahead, and chances aplenty for that lovely weather and a sleigh ride together for two.

MID-MORNING REPORT: 
  1. Overnight, the more well-known computer models such as the European trended our future storm toward a less impactful outcome, but still has a scenario producing accumulating snow for the I-95 corridor. 
  2. The Global Forecast System is delaying the onset of precipitation until Saturday, and extending it into Sunday, as well introducing more mixed wintry precip to include rain and sleet at times. 
  3. With precip possibly lasting intermittently to Sunday as indicated on the NOAA Weather Prediction Center's National Gridded Forecast Maps, it should be noted that refreezing of standing water may become an issue Sunday night as temps drop to the mid 20s across areas expecting snow -- including most of the Mid-Atlantic.
  4. Our Winter Stormcasters had an intriguing chat this morning on the similarities and differences between this upcoming event and the "Surprise Snow" of January 30, 2010 for the DC-Baltimore-Philly metro areas and interior sections. Are there comparisons that raise concern? We will outline those ideas in a new post this afternoon. We don't think there is "6 inches of partly cloudy" in the near future, but then again, stranger things have happened in weather before.

NOAA SURFACE MAP PROJECTION FOR 7 AM SUNDAY MORNING.
YEAH YOU KNOW WHAT THAT IS... A GOOD OLE' NOR'EASTER
7:00 PM 12/15 - With the potential of a significant early winter kickoff storm becoming more likely, we want to begin outlining some key points to ponder heading toward the last weekend before Christmas:
  • ONLINE SHOPPING TO AVOID THE RUSH? We URGE you to place order with online retailers immediately, and get it into the shipping stream before this storm affects inter-state commerce. Remember last Christmas, and the major problems that occurred with Amazon, UPS, Fedex and other shippers or retailers? 
  • If this storm produces heavy snow on Saturday, ordering online because you can't go out may not expedite some orders--- and could actually delay arrival until AFTER Christmas. How do we know this? It's a little known secret that one of the senior forecasters works at UPS. We have a sense of what the holiday shipping volume is, because some of us are unloading your packages! Monday December 22 may be one of the highest volume days of the year...
  • Now just imagine if a big storm keeps some shoppers at home on Saturday, and they order online instead, expecting packages to arrive problem free by Tuesday...
    SNOW, RAIN or WHAT? Computer model indications point to a widespread precipitation event for most of the Mid-Atlantic. While it's too early to say with certainty how much snow or where the heaviest will be, we can say by Saturday morning, most locations from the I-70, I-83 and I-95 corridors in Virginia, Maryland, West Virginia into southern PA have a strong chance of seeing accumulating snow.


    HOW MUCH LIQUID? The latest liquid projections from the NOAA Weather Prediction Center should be a strong indication most of us are in for something wet or white this weekend, as noted in the current Day 4-5 map below. If you add the projected amounts for you area from the map above for Thu night - Sat night, to the second part of the storm for Sat night - Sunday below, that gives you a general idea of liquid amounts. 

    As a representative location, we estimate BWI Airport will see about 0.55-0.60" of liquid in this event. That and other data will be refined further as the weekend nears and a better sense of storm outcomes becomes more clear. 



    STAY IN THE KNOW -- BEFORE THE SNOW! 

    If you would like to become a "Powderhound Insider" and get exclusive, specialized advance briefings from our Winter Stormcast Team this season, send us a simple message to: winter@footsforecast.org. You'll get a sample of free services to review with this storm as a perfect test to see if our info will be useful for you. We look forward to working the storms with you!



    Sunday, December 7, 2014

    19 comments:
    Heat Miser or Snow Miser?
    WHICH ONE VISITS YOUR REGION THIS WEEK?

    PHOTO CREDIT: AUTHOR NICHOLAS KAUFMANN HONORING THE PASSING OF ARTHUR RANKIN,
    PRODUCER OF THE MUCH-LOVED 1970'S HOLIDAY SERIES INCLUDING "YEAR WITHOUT A SANTA CLAUS"

    8:00 AM EST 12/7 (Forecaster Kyle Jackson and Mr. Foot) If you've ever seen those old-time Christmas holiday specials from the 70s, you know of all the characters they spawned (such as Winter Warlock, The Misfit Toys, etc), the two that became most popular over the years are none other than HEAT MISER and SNOW MISER!

    Looking at the weather plan for the week ahead, it would seem Heat Miser is having his way with the pattern. But lurking just offshore are new diabolical plans from Snow Miser (who we know always seemed to be Mother Natures favorite anyway;-)  

    Truth be told, we're not sure who's really in charge right now up there. After such a cold November, even normalized temperatures seem mild, right? How long will this last, you ask? Let's take a look at what ahead: 

    SYNOPSIS: While we know the Snow Misers out there would love to see the mild temperatures go…. Mother Nature has other ideas. 
    • As the week progresses we will see those temperatures drop back to the normal ‘December’ feel;
    • Snow chances for the Northeast will ramp up, with a possible Nor’easter late Tuesday night into Wednesday morning. 


    MONDAY: The calm before the storm? Areas from the Ohio Valley to New England will see a nice amount of sunshine thanks to some high pressure moving across the Great Lakes. Temperatures will range from around the mid-40s and 50s in the Ohio Valley to mid-20s and 30s in New England.

    MONDAY NIGHT-TUESDAY: Mostly clear skies across most of the Eastern U.S. will give way to temperatures falling around the mid-30s and 20s for overnight lows. 
    • Tuesday is where things will get interesting. A nice amount of low pressure spinning off the coast will bring a mix of rain, sleet and snow to areas from Maryland to Maine.
    • Snowfall accumulations right now are looking heavier closer to the coast and less the farther you go inland. Temperatures will stay around the mid-30s for highs.
    • Sadly, it seems no snow for SouthTown in this go around


    MID-WEEK TO WEEKEND: Beyond the big storm on Tuesday night and Wednesday morning, some leftover scattered flurries may hang around for Wednesday in New England. For the rest of the week, we should stay dry thanks to more high pressure pushing through. Temperatures will hangout around the mid-30s and low 40s all week.


    LONG RANGE TAKEAWAYS?

    • Monday will be a calm day before the storm to take care of any items outdoors you may not want affected by snow and wind.
    • The BIG item this week will be the Nor’easter’ on Tuesday night into Wednesday morning that could put down a good amount of snowfall for areas from eastern Maryland to Maine.
    • Rest of the week will return to seasonable temperatures for most of the east, in the mid-30s and 40s while we stay dry thanks to High pressure.

    Monday, December 1, 2014

    9 comments:
    "The sun doesn't shine, the world doesn't turn."
    NASA's Pic of the Day from December 22, 2007

    6:30 PM EST 12/1 (By Kentucky Team Lead Forecaster Chris Reece & the Lead Story Team)
    For those who frequent this website and our team's regional or metro Facebook pages, we know there are times when a gap between updates causes "uneasiness." Especially in winter, we are told by people in various parts of the Mid-Atlantic that "you guys really need to update more, and do more long range stuff." 
    Some of these readers even report that others come to THEM seeking an inside scoop: "Got any inside info from Foots?" they are asked. So to help our long-time readers get your sun  shining righter and world turning better, we are launching a special weekly basic Long Range feature, starting today! 

    SYNOPSIS: This time last week we were watching closely for a major winter storm to roll up the east coast in the coming days. That led us into a cold Thanksgiving time period that had some festive flakes to go along with it. Now we find ourselves facing the full blown holiday shopping season right upon us. The question now is, “Where will the pattern take us next... into Winter or back to Fall?"
    Well my friends, it appears the winter pattern will eventually reload, and should be active over the next 10 days. Let’s start with now and work forward. 


    • MONDAY: The week started  much warmer than it will end. Areas from Kentucky all the way over to Maryland experience temperatures in the 50s to upper 60s, as the area of high pressure that brought the colder temperatures last week now sits just off the southeastern coast, which  produced southwest wind, and thus, warmer temperatures.
    • MONDAY NIGHT-TUESDAY: Temperatures crashed Monday afternoon much of the eastern half of the country bringing highs from the 60s to lows in the 20s. This will set the stage for a wintry mix of rain sleet and snow for select locations in the Mid-Atlantic, especially Maryland into Pennsylvania and the Virginia/West Virginia mountains.
    • MID-WEEK TO THE WEEKEND: Beyond that, subtle rain chances will continue as our front stalls out and slowly retreats back to the north over the course of the week, but things shouldn’t be a washout by any means for most of us. We then continue to warm up to seasonable temperatures. 
    Long range forecast data then begins to send more shots of cold air in the 9 to 10 day period. That’s likely a hint of the back and forth period of cold and warm air that will take place before the cold begins to take over for the middle and end of this month.


    THE LONG RANGE TAKEAWAY?

    • The next 10 days will feature a day or two of cold with a small chance of wintry weather that shouldn’t be too disruptive, at least not for Maryland just yet. 
    • Areas west towards Kentucky will want to stay on close look for wintry weather potential. 
    • Conditions gradually warm towards seasonable temperatures by next week with off and on rain chances. Beyond that, cold weather looks likely to return toward end of next week. 
    • The southern jet stream has been active lately, and if it continues into the middle and end of December, which it certainly looks possible, then the Thanksgiving storm was only the beginning of what could be an active winter period.

    CAN I STILL PUT UP THE LIGHTS?
    Yes, but you’ll want to be very vigilant for scattered showers here and there. Otherwise the next 5-10 days will at least hold Arctic air at a distance in Canada. But those opportunities to get it done won't last much longer that that.




    NEED THE INSIDE SCOOP? JOIN OUR CLUB! 
    For those who want MORE and would enjoy exclusive Insider access to our briefings, reports and insights, this winter consider joining the "Powderhound Club." Just send us a simple message to winter@footsforecast.org and we'll provide the latest Powderhound Insider newsletter with details on what's coming in December, special discounts on hoodies and reports from the Winter Stormcast Team.
    If you have suggestions on features we can include in the weekly long range report, let us know in the comments below. 
    2 comments:
    "Surely, you can't be serious?
    Yes, I'm serious, and don't call me Shirley." 
    -Leslie Neilsen, in a famous line from a 1980s comedy (Youtube clip)

    Screen capture of Frederick MD NWS forecast as of 3:30 AM 12/1

    9:00 AM 12/1 - Another Fall tease, followed by another wintry surprise. Then again, it is December now, so time to get our game face on. Even though long range temperatures are set to go above normal in the 6-10 day period ahead, surprises lurk in the short range:

    • If you haven't checked your National Weather Service point-and-click local forecast, better do that soon. By this evening, following passage of a cold front, resurgent High pressure system nudges in dry, much cooler air tonight from the north. 
    • As the flow switches to north overnight, temperatures across the region drop to near 30 as shown on our snippet from the Frederick, MD forecast graphic

    It's a classic "Cold Air Damming" setup, as alluded to on the NOAA surface map. It is a process where surface cold air wedges down the east side of the Appalachians, evidenced by the "bowed" isobar lines you see over the Mid-Atlantic states. Running over  the top of the denser air below will be moisture and southerly winds aloft streaming in from the Gulf of Mexico. The result at surface is temperatures hold right around 32 F as the moisture works itself out as either sleet or freezing rain. 

    Regardless of the meteorological technicalities, Tuesday looks to be a challenging day for schools and travelers in the Blue Ridge region and along the PA/MD line.

    Or as they said in the Airplane movie, "Yes I'm serious, and don't call me Shirley."

    Forecaster Foot and the Maryland Team

    Saturday, November 29, 2014

    5 comments:

    Time for a "Breakthrough"?
    -Single by Disney's Lemonade Mouth (Youtube lyrics)

    8:15 AM EST 11/29 - With a mostly tranquil rest of the Thanksgiving weekend upon us, it's time to ask the real question looking ahead: 
    What kind of weather pattern is going to breakthrough next?

    PHOTO CREDIT: Mr. Timothy Butz of Howard Co., MD
    THE GOOD NEWS: A significant storm in the eastern U.S. is not expected over the next 5-7 days. Instead, a brief mild period looks likely as we start the first week of December. 

    Long range temperature probabilities are ABOVE NORMAL for a majority of the U.S. (woohoo!)  from Dec 3 - 7 as seen on the Day 6-10 projection from the NOAA Climate Prediction Center.




    THE BAD NEWS: The "atmospheric river" pattern of this last storm could be a sign of things to come. At one point, the storm's moisture plume reached all the way to the Equator! Add extra fuel from a resurgent El Nino, bring in some good ole' Siberian High pressure systems - and by end of next month, a stormy sequence may be rolling once again across the Eastern U.S. 

    Wednesday, November 26, 2014

    7 comments:
    Welcome to the Powderhound Club!

    A HUSKY AWAITS THE POWDERHOUND INSIDER
    Credit: and a fun poem with it, at Rhinestone Armadillo
    11/27/14 - In the wake of a storm that brought a White Thanksgiving to some not seen in 25 years -- we would like to introduce a special opportunity for all our readers across the Mid-Atlantic. 

    Whether you are a life-long snow enthusiast, a decision-maker in your organization, or a busy parent, we know there are times you need access to specifics on what the weather will do next. 

    That's where the club comes in, and we're excited to reveal what is planned for this program!

    Request a FREE Powderhound Insider Newsletter with details on the December pattern and beyond...

    JUST SEND US A SIMPLE MESSAGE TO winter@footsforecast.org


    1 comment:
     Are we done yet, or is there more? 

    The short answer: Almost, but...

    2:36 PM EST 11/26 After a brief lull following the mid-morning snow BOOM, some areas are seeing snowfall restart. The good news is that the "back edge" is approaching, but the bad news is it may come with a final dump of snow between 4-5 PM for the I-95 corridor. 
    • The storm may end the way it started, strangely, just backwards: A rush of snow, then rain showers. 
    • After the precip clears, temps should begin dropping on northwest winds - and lows of 27-30 in northern and western counties could produce refreezing of standing water. 

    HOLIDAY TRAVELING? We suggest you get going as quickly as possible, before the back edge brings a final grand finale. We bid Godspeed to all travelers and our best wishes for a smooth trip. 

    THANKSGIVING DAY: Cold and breezy, which will help evaporate standing water, but will make for a raw day. Highs holding in the upper 30s to 40 F. 

    NEED BETTER ACCESS TO OUR TEAM? We have a solution for those looking to get the inside track an seek life beyond Facebook. It's called the "Powderhound Club" and by joining, when "we know, you'll know." No more weather surprises, get rapid access to our info to aid in those tough decisions, and we'll work the storms together!

    To pre-register for the Powderhound Club and get your first FREE Insider report, visit this link, (Or skip a step and just send a brief note to winter@footsforecast.org

    Safe travels everyone, and thanks for your support during this early winter kick-off. 

    Mr.Foot, Forecasters Connor, Mike and the Maryland Team

    Tuesday, November 25, 2014

    Know the ground, know the weather

    27 comments:
    "Know the ground, know the weather
    and then total will be your victory."
    - Sun Tzu, The Art of War, c.400-320 b.c



    8:45 AM EST 11/26 - TEMPERATURES ACROSS MID-ATLANTIC DROPPING AS EXPECTED. STORM HAS A MOISTURE PLUME THAT EXTENDS TO SOUTH AMERICA.
    • SNOW WILL MIX WITH RAIN FROM NORTHWEST TO SOUTHEAST THIS MORNING. EXCEPT FOR AREAS ALONG AND EAST OF I-95, WHICH STAYS RAIN/SLEET UNTIL 1-2 PM. 
    • NORTH AND WEST OF I-95, EXPECT HEAVY WET SNOW STARTING NO LATER THAN 11 AM, CREATING DANGEROUS VISIBILITY ISSUES, EVEN IF ACCUMULATION IS SLOW.
    • PARENTS OF STUDENTS IN SCHOOL DISTRICTS CLOSING EARLY ARE REMINDED THAT DANGEROUS DRIVING CONDITIONS MAY EXIST DURING DISMISSAL AND TRANSPORT HOME. PLEASE MAKE EVERY ATTEMPT TO SEE THAT YOU ON TIME FOR PICKUP, OR ARE HOME BEFORE ELEMENTARY-AGE CHILDREN ARRIVE. 
    • WE HAD HOPED TO AVOID REPEATING THE FEB 2007 DISASTER. Perhaps next time.

    7:30 PM EST 11/25 - COASTAL LOW FORMING OFF GEORGIA, RADAR SHOWS EXTENSIVE MOISTURE ACROSS THE SOUTHEAST SUGGESTING FORMATION OF AN "ATMOSPHERIC RIVER."
    • SCROLL BELOW FOR FINAL SNOWFALL MAP | "STORM GRADE" TOTALS in progress
    For those still unconvinced this system will surprise many of us with significant heavy snow, take note of the point of origin for much of the moisture heading our way:
    - From the Atlantic? Some, not all.
    - From the Gulf of Mexico. Sort of.

    - How about the East Pacific? 

    The real answer: ALL THREE. This system is tapping into moisture sources from three bodies of water, starting in the East Pacific, then scooping up more in the Gulf, and finally tapping Atlantic sources once the winds shift northeast.

    TAKE A LOOK FOR YOURSELF! Below is a NOAA Water Vapor image for the Caribbean, E Pacific and western Atlantic, showing an unbroken tropical feed of moisture 2,000 miles long originating from the West coast of Mexico-- all the way across the Gulf of Mexico, and all the way north to your door. THAT's why we're confident this system has potential to be significant.



    WHAT TO LOOK FOR: This is, as they would say, a "fluid situation." We present several look-fors that will help you detect in the AM hours which direction this storm forecast will go-- either BOOM or BUST. Our thanks to Forecaster Troy from the University of Maryland, College Park for this assessment:

    1. If temperatures are still well above freezing by noon time, snowfall accumulation could be less than expected.  
    2. If you see snowing coming down heavily in the morning hours near I-95, this indicates the "bust scenario" of colder temperatures is playing out. Thus, the storm is likely to over-perform, exceeding current accumulation forecasts.
    3. If the storm is stronger than forecasted, higher snowfall rates would also produce a more rapid drop in temperatures. This is known as "evaporative cooling" in which the formation of snowflakes from water vapor actually chills the surrounding air-- leading to more snow, falling faster and sticking easier because there is more of it to overcome warm surfaces.
    FINAL SNOWFALL MAP 



    BUST SCENARIO 1: TOO WARM! (75% chance) With so much warm air in place ahead of this storm, it is "on its own" to cool down the atmosphere enough to have "snow producing "temperatures. 
    • In this scenario, those in the C-2” zone would see nothing, the 2-4” zone would struggle to get a coating, and the 3-6” zone could only pick up a couple of inches. There are two sub-possibilities here:
    A) Surface temperatures don’t cool down below the mid 30s. We end up with a “white rain” of snow that can’t stick, or if the warm layer is deep enough, just rain. This could move across much of the metro areas during the heaviest precipitation, preventing accumulating snow.
    B) Warm air noses in in the mid-troposphere during the height of the storm. This flips precipitation along I-95 to all rain instead of a mix.
    BUST SCENARIO 2: OVER-PERFORMING COLD! (25% chance) On the flip side, we could have abundant evaporational cooling that puts temperatures at 31 or 32° instead of a few degrees higher. 
    • That small difference means that much more snow can stick. In this scenario, western areas could see up to 8” , the 2-4” zone could be more like 4-6” , and the C-2” zone sees up to 4”
    BOTTOM LINE? Sun Tzu was right, if you know the ground, and know the weather, then your victory will be total. In less than 12 hours we all shall find out who shall be victorious in the call for this first winter storm of our 11th season of forecasting!


    Contributors: 
    Forecasters Mike Natoli and Troy Arcomano, Univ of MD. Advisor R. Foot, Forecasters Jason Mitchell, Connor Meehan

    "Let The Storm Rage Onnnn...."

    12 comments:
    "Let The Storm Rage Onnnn...."
    -Elsa, from Frozen (2013)
    • NEW LIQUID PROJECTIONS OF 1.0" FOR I-95 CORRIDOR SUGGEST LESS SNOW, MORE RAIN FOR METRO AREAS.
    • APPALACHIANS, INTERIOR NORTHEAST WOULD HAVE HIGHER ACCUMULATIONS IF AXIS OF HEAVY SNOW SHIFTS WEST 


    10:15 AM 11/25 - SCROLL DOWN FOR STORM OVERVIEW & SNOWFALL MAP. 
    Latest resources for your reference:

    DISRUPTIVE WINTER STORM TO IMPACT MID-ATLANTIC 
    & NORTHEASTERN STATES INTO THANKSGIVING MORNING


    Monday, November 24, 2014

    Red Pill or Blue Pill?

    18 comments:

    Red Pill or Blue Pill?
    (Sorry Ravens fans, no Purple Pill this time...)

    WINTER STORM WATCHES POSTED FOR MID-ATLANTIC & NORTHEAST
    (Click on link above to see latest watches and your local NWS office)




    MARYLAND: NEAR 70 DEGREES MONDAY, 5 OR MORE INCHES WEDNESDAY?!?

    3:55 PM 11/24 UPDATED: Scenario A & B Map Below

    • Special FREE teleconference briefing available Tuesday late AM and early PM to ask our forecasters your questions about the storm. Send us a message to winter(at) footsforecast.org to register for the call. Indicate what weather information about this event would aid your decision-making. 
    • Four (4) time slots will be available, pick any of them at your convenience.
    • For companies or organizations, denote one representative who can report back to your group. A briefing package will be sent Tuesday AM with call-in details.


    OVERVIEW (By Forecaster Mike Natoli) Regardless of heavy rain or snow, we all are likely to see a disruptive storm moving up the East coast at the very least. 
    • We have refined our ideas to two scenarios depending on surface temperatures. Temperatures will be marginal, near or slightly above freezing, which will initially make snow accumulation difficult. However, as computer models have been projecting for the past 24 hours, high snow fall rates may overcome warm surfaces and create a surprise situation Wednesday afternoon.
    • We remain cautious on this storm, because a slight shift of precip arrival or type over just 2 hours on Wednesday morning will impact the entire day's forecast. If we decide we need to make a snow accumulation forecast, that will be issued either later tonight or Tuesday morning. Until then we have narrowed the potential outcomes to TWO SCENARIOS, outlined in the next section.


    Get Ready For BOOM!

    5 comments:
    Get Ready For BOOM!

    MAJORITY OF COMPUTER MODELS POINTING TO A 
    PERIOD OF HIGH IMPACT HEAVY SNOW WEDNESDAY  PM 
    ACROSS THE NORTHEAST METROPOLITAN REGION.

    10:45 AM EST 11/24 UPDATED: LATEST SNOWFALL PROBABILITIES from the NOAA Weather Prediction Center should give ANYONE pause if you plan to travel Wednesday, or are in essential services. Teachers, this is a great opportunity to show your students why understanding the legend on a map is critical to good decision-making.
    • INCREASING PROBABILITY OF AT LEAST 8"  NORTH AND WEST OF THE I-95 CORRIDOR. As noted below in the green banding. Source: NOAA WPC Winter Suite
    • CURRENT DATA PROJECTIONS SHOW AT LEAST 0.50" LIQUID FALLING AS SNOW 12-6 PM WEDNESDAY IN METROPOLITAN MID-ATLANTIC. Source: GFS for BWI


    THE TAKEAWAY? We don't care that it's going to be 70 F today in some places. That's the ruse. Don't fall for it. How many thousands of travelers on Wednesday will allow today's aberrant warm weather to fool them into false security that "roads will be just fine, sheesh. Not like it's January, right?" 

    WRONG: The issue WILL NOT be snow covered roads, it will be VISIBILITY due to heavy wet snow combined with high volume traffic. One person decides to slow to a crawl on 95 at 3 PM in the snow, and BOOM. There goes your holiday weekend. Think about it. Plan ahead. Consider how you can adjust your plans now before reality hits and its too late.

    OUR FEAR: Unless something changes drastically in the storm track trends, this series of unfortunate events on the Wednesday before Thanksgiving could become the worst day of mass travel in modern times, if we have a repeat of January 26, 2011.