Winter Stormcast Zone

2011 Archives: 1/15-2/1

8:00 pm EST Tue 2/1/2011 (Forecaster Jason) On this first day after a long and tiresome January for many, our first winter storm of February has wreaked havoc across much of the United States. A new batch of precipitation is set to move into the Mid-Atlantic tonight, and Ice Storm Warnings are posted for millions of residents from Southeastern PA to the NYC Metro area. (Link to NWS map: http://www.erh.noaa.gov/

TIMING: As the storm system intensifies over the Ohio Valley, more precipitation will move into the Mid-Atlantic  by the late evening hours. Areas from Central Virginia eastward to Southern Maryland and the lower Eastern Shore will likely have surface temperatures above freezing. Thus, precipitation in these areas is expected to fall in the form of plain rain. However, temperatures may be just below freezing for Central Maryland and the upper Eastern Shore, with freezing rain expected. Freezing precipitation will also move into Pennsylvania this evening - reaching the Philadelphia metro area by midnight. Ice accumulations of over 0.50" are expected in the Ice Storm warned area.

TONIGHT'S IMPACTS Central VA-Southern MD: Depending on the extent of cold air locked at the surface, areas near the Mason Dixon line into northern Delaware may experience an extended period of freezing rain into Wednesday morning, all rain for areas south of US-40. (Forecaster Jason, Calvert Co MD)

CAUTION: In areas where ice accumulates over one quarter inch, this will likely bring down power lines and tree limbs, leading to widespread power outages. We urge all residents affected by this storm to use extra caution while outdoors, and to remove ice and snow from storm drains before the storm strikes. (Forecaster Jason. Collaborators: Forecasters Connor, Dakota, Winterman Advisors: Winstead, Lear, Foot)

TONIGHT'S IMPACTS  Northern Maryland-Baltimore Metro: Freezing rain expected from this second batch of precipitation is expected to accumulate one quarter inch or more from Northern Virginia eastward to the southern portions of the Baltimore metro. Areas near the Mason Dixon line may experience freezing rain amounts between one quarter and one half an inch. Total liquid precipitation amounts for the entire storm will be around 0.50-1.00”, as shown on NOAA’s HPC map

TONIGHT'S IMPACTS Central & Southern Pennsylvania: Snow and sleet will be the dominant precipitation type tonight. Between last night and this afternoon, one to three inches can be expected in from Harrisburg to York and two to four inches can be expected in State College and locations northward. Before transitioning to freezing rain, snow and sleet will once again impact the region early Wednesday morning leaving a general one to two inches in locations south of State College. Depending on the temperature at 1500 meters above the surface, areas around and north of State College could receive snowfall in excess of four inches.

(Forecasters Foot, Jason, Winterman, Terence, Dakota. Advisors Lear, Berk and Winstead)

9:00 AM EST 2/1/2011 Computer models at this time are trending "Our Groundhog Event" toward a major rainmaker for the southern Mid-Atlantic, with heavy snow possible in Pennsylvania and a major ice event extending back through the Ohio Valley to the Tennessee Valley and Southern Plains. Blizzard warnings are up in nine States.  These storms will impact wide areas the U.S. Updates of the timing, path, and precip types and levels will be presented by your Foot's Forecast Team as we will update throughout the day.


Review NOAA discussions on the event via the HPC Preliminary Extended, the Heavy Snow Discussion, and the latest roundup of Forecast Discussion in the Ohio Valley area from this link by the Pittsburgh NWS office (Advisors Lear and Foot)

"Well hon, there's another storm..." 

2:15 PM EST 1/28/11 A good portion of the Eastern U.S. will see not one, but two Clippers pass through today and tomorrow.  Today's could bring 2 or so inches in localized areas, tomorrow's...not so much. Many school systems are still shut down from the one-two punch Wednesday and Thursday.  (Image: Future Radar Analysis by the Weather Research and Forecasting Model (WRF) as rendered by Wright-Weather, LLC.)

ANOTHER STORM? Some computer models are showing a significant precipitation event to arrive on on Groundhog Day.*   You can review the latest long range analyses posted in the US Hazards Assessment (third paragraph under detailed summary and  the preliminary discussion from NOAA's Hydrometeorological Prediction Center (HPC) (the daily final extended is posted in afternoon).

Early indications are that a considerable portion of the country east of the Rockies will be impacted by this event in the Tuesday-Thursday time period. Total liquid equivalent projections for the day 5 period show a broad area of Gulf-fueled precipitation that has only one way out: Through the Mid-Atlantic and Northeast. Our team will continue reviewing data projections,  but everybody reading this knows that trying to nail the specifics of a storm five and six days out is statistically unreliable. Once the event is "inside 5 days" we will begin more intensive analysis - starting Saturday.

As Confucius might say this is the winter of "a heavy load on a long journey" and this storm information may be wearisome for those dealing with multiple rounds of winter weather. Our team feels obligated to continue providing and early look at the possibilities, given that we are all trying to reassemble or blown schedules and need advance notice when weather threatens.

*So...will it be The Great Groundhog Day Caper or That Storm that Rained All The Snow Away?? [please submit your own Groundhogs Day Pun, about the Event or the Movie. See the comments section on the 411 page].

Stay tuned...we'll be working on it...and keep checking for updates! (Advisors Lear and Foot)

"OK, that's over.
Wait, what?...there's more??"

5:00 PM Thursday 1/27/2011-  After the "Snow-Surprise" yesterday morning, much of the Forecast area got hammered last night with a 6-10"+ "MINI-BLIZZ" in a few short hours.  This writer had no power for over 14 hours, and received a 10.1" snowfall in approximately 6 hours.  Many side roads are still snow/ice covered thorough out  this zone, and, at this writing, parts of I-95 in the NE are still difficult, if not impossible, to travel.

The Winter Stormcast Team is carefully watching the development of three Winter Weather events.  There are two Clippers coming into the area, one Friday, the other Saturday.  Another, larger storm may affect us during the middle of next week.  At this time, the first of the waves could bring the Mid-Atlantic about an inch or so on Friday. Saturday's disturbance may bring a "dusting", perhaps even changing over to rain. The latest development for next week might affect us in a big way, but it is too soon to tell if we will have  

The Great Groundhog Day Shadow Eliminator

or

That Big Rainstorm on February 2nd

Rest assured, your Foots Forecast Team is going to keep a close watch on all possibilities, and will provide you with updates over the upcoming hours and days. (Advisor Lear)

"Here it comes, ready or not!"

4 PM- Wednesday 1/26/2011   TEAM STATEMENT: The Winter Stormcast Team is carefully watching the development of this storm. MANY WINTER STORM WATCHES HAVE UPGRADED TO WARNINGS OVERNIGHT. Low pressure that developed along the Gulf coast, is moving up the East Coast today. Many area have seen a measurable snowfall this morning, closing schools, offices, and other businesses.  Driving has become treacherous, even in areas that are receiving rain, as the cold surface may be creating icy conditions.  Snow and sleet mayther businesses.  Driving has become treacherous, even in areas that are receiving rain, as the cold surface may be creating icy conditions.  Snow and sleet may be changing to rain for a period of time, but will change back, or become, heavy snow before ending late Wednesday or very early Thursday.  Snow amounts could exceed 8 inches, especially in areas further North.

Numerous Winter Storm Watches and Warnings are posted and expanding from the Southeast into the Mid-Atlantic as noted on the NWS Eastern Regional Advisory map shown here. For details on specific impacts in the Southeast, please visit their regional facebook forecast center for that area.

As the coastal storm moves north of the region Wednesday evening, an upper level low associated with the system will swing through the region. With colder air being drawn eastward, we expect most areas to changeover to snow. Significant snowfall will occur in many area of the Mid-Atlantic.  Banding may cause snowfall rates of 3 inched per hour. Details on impacts to specific regions below:

WEST VIRGINIA, VIRGINIA TO MARYLAND:  Areas that started out with rain this morning should see a changeover to snow by late afternoon.  The Mountains may receive an addition 5 to 7 inches of snow.  Areas closer to the Coast, will receive about 3".

Our final total snowfall projections ending Thursday Morning: 

BWI - 9.5 | Baltimore City - 10 | Annapolis - 7  

Westminster - 10 | Bel Air - 11 | Columbia - 8.5|

I-95 CORRIDOR TO EASTERN PA: Any rain will changeover to heavy snow by rush hour in Washington, D.C., Baltimore, and later in Philadelphia. These Metro  and Suburban areas should see total snow amounts in the 5-8" range.  Amounts will range higher in the Northern areas of the Mid Atlantic.

NORTHEAST:  The Eastern regions of the Northeast are braced for snowfalls of up to 8"+ until the event ends very early Thursday.  See details.


Our final total snowfall projections ending Thursday afternoon;
Philadelphia - 10.75 | Trenton - 11.00

Newark - 9.00 | New York City – 8.75
Hartford – 7.25 | Providence – 8.25 | Boston – 10.00

UPDATE SCHEDULE:  We will continue collaborating and will revise this statement as needed today.

(Authors: Forecaster Jason. Collaborators: Forecasters Winterman, Connor, Dakota, Advisors: Keith K., Winstead, Lear, Foot)


4:00 PM Monday 1/24/2011

TEAM STATEMENT: As the Mid Atlantic continues to experience brutally cold temperatures, the Winter Stormcast Team is continuing to monitor the potential for a major storm system to impact the Mid Atlantic Wednesday. A storm system will develop along the Gulf coast Tuesday, and will move up the East Coast during the day Wednesday. (link shows one computer model projection for 8 AM Wednesday). However, multiple scenarios are possible with the track of this storm. Recent liquid equivalent projections for this storm on Wednesday range from 0.85" in Raleigh, NC (mostly rain) to 1.37" for Richmond VA (mostly snow, some rain) to 0.59" at BWI Aiport. The animation below is the latest simulated basic model output from the NOAA Global Forecast System as represented on the coolwx.com website. 

SCENARIO A : "THE MIX"

The storm tracks along the coast Wednesday, bringing a mixture of rain and snow for the immediate I-95 corridor from Washington, D.C. to Philadelphia. Some snow would be possible for areas west of I-95 in western Maryland and western Virginia. Areas from Southern Maryland to the upper Eastern Shore would have a mix of rain and snow or just rain, with all rain for the Atlantic beaches. Liquid precipitation totals for the I-95 corridor could exceed one inch in some places, however light snowfall amounts would be confined to a possible changeover to snow on the backside of the system.

SCENARIO B : "MINI-MIX" The track of the storm would be slightly eastward from scenario A. With Arctic high pressure displaced into the Atlantic, surface temperatures would not be much colder. Less precipitation amounts would fall, and the rain/snow line would only shift slightly eastward.

SCENARIO C: "DELUGE" The storm intensifies quicker than expected, resulting in a much more westerly track. In this scenario, rain would fall as far westward as the I-81 corridor. Due to the proximity of the surface low and its intensity, heavy rainfall amounts of 1-2 inches along with gusty winds would be a concern for the entire I-95 corridor.

SCENARIO D: "SEE YA" The storm would be allowed to take a track sparing the entire I-95 corridor direct impacts. With no high pressure to block to the storm, the surface low would track off the Southeast coast and out to sea, with little to no precipitation for the I-95 corridor.

At this time, we believe Scenario A is most likely to verify, however all of these possible scenarios are possible with this storm system. We will continue posting updates as indications become clearer on the details of this storm.

(Author: Forecaster Jason. Collaborators: Forecasters Dakota, Connor, Winterman. Advisors: Keith K., Winstead, Foot)

RESULTS FOR 1/20-21 SNOW EVENT
10:00 AM 1/21/2011 The storm passed slightly further North than many had predicted.  Our updated forecast  last evening accounted for that, and our snowfall amounts of 1-2" (and 2-4" to the North) held fairly true for the Mid-Atlantic Region.  At this time, Winter Storm Watches and Warnings are still posted in most of New England.  Bitter cold weather will come East to day, and may cause freezing as far South at Florida.

TIME FOR A NEW CONTEST Dr. Ratio, who resides in Northern Maryland, has challenged you to a small test.  NOAA's 30-year  average for liquid to snow ratio for his area is 11:1, that is, one inch of liquid will produce 11 inches of snow.  He received the predicted 2.1" of snow last night,  and his L/S ratio was NOT 11:1.

Your job is to guess how much liquid that he did get, and what was his liquid/snow ratio.  Post your reply in the comment section of the 411 page, and the answer will be posted tomorrow morning.  

WINTER FORECASTING IMAGERY AND LINKS