Feb 19, 2012 Snowstorm Summary

The first significant winter storm of the season was long overdue, but final developed over the central Appalachian region on Sunday Feb 19, 2012. Temperatures had been unseasonably warm in the days leading up to the event (50s and 60s Saturday the day before), resulting in warm ground conditions. It took a timelycombination of colder air filtering back into the region from the north throughout the day Sunday, and then heavier bands of precipitation moving across the region late enough in the afternoon and into the evening, to get snow to begin sticking in earnest. The heavy wet snow that fell across the entire Blacksburg forecast area, including a few inches across north-central North Carolina, was enough to cause quite a few trees and tree limbs to fall onto power poles resulting in extensive power outages. Over 60,000 AEP customers across Virginia and West Virginia were reported without power at one point late Sunday evening. Numerous traffic accidents were also reported during the heaviest snowfall late in the day on the 19th. Snowfall totals are shown and listed at the bottom of this page, with 8 to 9 inches in a number of locations across the Appalachian mountains of Virginia and West Virginia, and 6 to almost 8inches as far east as Lynchburg.

Here are a couple of high resolution satellite images showing the swath of snow across the region as observed the following Monday morning:

Meteorology Overview

The storm system in general took a common track that passed just to the south of our region from the Gulf Coast to the Carolina Coast, before strengthening and moving northeast into the Atlantic. This track and surface low pressure development is know as a "Miller A" type system, and was common with many of our region's significant snowfalls during the 2009-2010 season. (More information about these kinds of winter storms click here). This storm track often occurs with cold air already in place across the region from an Arctic high pressure system anchorage over the Northeast U.S. That ingredient was NOT in place during the Feb 19, 2012 event, but colder high pressure was slowly building in from the northwest and some of it eventually spilled around the east side of the Appalachians as well. While adequate moisture was expected for a significant event, there were several concerns about just how much snow would accumulate. This depended on whether colder air would drag south fast enough, would the timing of the heavier precipitation (which would also help pull down colder air from aloft) would reach the area during the day time when the sun's energy would help keep the already warm ground above freezing, or would it come in late enough during the day where it would have a much better chance of sticking more quickly (and once that process begins it can accumulate more rapidly). Other questions concerned exactly where the heaviest band of precipitation would set up to bring these higher snowfall rates. Computer models first suggested this would take place more across the north and western portions of the region, and also more during the afternoon. Later computer forecasts suggested this favored zone shifting a little farther south, with colder air arriving from the north a little sooner and heaviest precipitation arriving later in the afternoon and into the evening. These trends resulted in National Weather Service Forecasts trending a little farther south with the heaviest snow (and thus the watches and warnings), as well as slightly higher amounts given the better timing with colder air and lowering sun (thus less melting from below).

In fact, these ingredients all managed to come together just at the right time as the surface low moved to near the coast and an upper level wave of energy helped enhance the zone of heavier precipitation, with embedded heavier bands of snow arriving late in the afternoon with colder air now in place. The loop below shows the evolution of the surface features and the radar depiction of the precipitation. The time is labeled at the bottom in universal time (UTC or Z), with 1802Z being 1:02pm local time, and 210Z2 being 4:02pm, etc).

 

Here is a snapshot of the radar mosaic valid at about 21Z or 4pm, showing some heavier bands of precipitation beginning to move across parts of the New River Valley and north central NC).

 

Finally, here is the resultant map of snowfall totals as reported to the National Weather Service during and just after this event. Keep in mind that as the snow partially melted from below and also compacted since it was relatively wet and heavy, these amounts could ahve been much higher if it had been colderto begin with. We are extremely appreciate of ALL the many people that relayed snowfall reports to us via the phone, email, or Facebook. Thank you!

 

Storm Totals Text

SPOTTER REPORTS

NATIONAL WEATHER SERVICE BLACKSBURG VA

1040 AM EST MON FEB 20 2012

 

THE FOLLOWING ARE UNOFFICIAL OBSERVATIONS TAKEN DURING THE PAST 15

HOURS FOR THE STORM THAT HAS BEEN AFFECTING OUR REGION. APPRECIATION

IS EXTENDED TO THOSE WHO PROVIDED REPORTS. THIS SUMMARY IS ALSO

AVAILABLE ON OUR HOME PAGE AT WEATHER.GOV/BLACKSBURG

 

********************STORM TOTAL SNOWFALL********************

 

LOCATION          STORM TOTAL     TIME/DATE   COMMENTS                  

                     SNOWFALL           OF

                     /INCHES/   MEASUREMENT

 

NORTH CAROLINA

 

...ALLEGHANY COUNTY...

   SPARTA                 5.0   954 AM  2/20  LAW ENFORCEMENT        

   3 NE GLADE VALLEY      4.0  1208 AM  2/20  TRAINED SPOTTER        

 

...ASHE COUNTY...

   CRESTON                4.5  1020 AM  2/20  TRAINED SPOTTER        

   JEFFERSON              4.0  1018 AM  2/20  LAW ENFORCEMENT        

 

...CASWELL COUNTY...

   4 ESE QUICK            3.0   316 AM  2/20  TRAINED SPOTTER        

   YANCEYVILLE            2.0   856 AM  2/20  LAW ENFORCEMENT        

   CAMP SPRINGS           2.0   900 PM  2/19  PUBLIC                 

 

...ROCKINGHAM COUNTY...

   WENTWORTH              3.8  1157 PM  2/19  TRAINED SPOTTER         

   2 S HARRISONS CROSSR   3.5   820 PM  2/19  TRAINED SPOTTER        

   1 ENE REIDSVILLE       3.5   955 PM  2/19  TRAINED SPOTTER        

   REIDSVILLE             3.0   857 AM  2/20  2-3 ACROSS THE COUNTY. 

   1 W OREGON HILL        3.0  1030 PM  2/19  TRAINED SPOTTER        

   EDEN                   3.0  1101 PM  2/19  TRAINED SPOTTER        

 

...STOKES COUNTY...

   3 NNW SANDY RIDGE      3.0   700 AM  2/20  TRAINED SPOTTER        

   2 NNW SANDY RIDGE      3.0   840 AM  2/20  TRAINED SPOTTER        

   DANBURY                2.8   859 AM  2/20  LAW ENFORCEMENT        

   2 NNW CAPELLA          2.5   831 PM  2/19  PUBLIC                 

 

...SURRY COUNTY...

   LOW GAP                4.0   850 AM  2/20  LAW ENFORCEMENT        

   DOBSON                 3.5   850 AM  2/20  LAW ENFORCEMENT        

   1 S DOBSON             3.0   939 PM  2/19  CO-OP OBSERVER         

   MOUNT AIRY             1.5   930 PM  2/19  LAW ENFORCEMENT        

 

...WATAUGA COUNTY...

   SEVEN DEVILS           4.5   919 PM  2/19  SEVEN DEVILS PD        

 

...WILKES COUNTY...

   WILKESBORO             2.0   910 AM  2/20  1-3 ACROSS COUNTY.     

   HAYS                   2.0   807 PM  2/19  PUBLIC                 

   NORTH WILKESBORO       1.0  1009 AM  2/20  CO-OP OBSERVER         

 

...YADKIN COUNTY...

   JONESVILLE             3.5   716 AM  2/20  TRAINED SPOTTER        

   YADKINVILLE            2.0   903 AM  2/20  LAW ENFORCEMENT        

 

VIRGINIA

 

...ALLEGHANY COUNTY...

   4 E COVINGTON CITY     9.8   408 AM  2/20  TRAINED SPOTTER        

 

...AMHERST COUNTY...

   AMHERST                7.0   900 PM  2/19  TRAINED SPOTTER        

   2 WNW ELON             6.0   823 PM  2/19  TRAINED SPOTTER        

 

...APPOMATTOX COUNTY...

   STONEWALL              5.5  1032 AM  2/20  TRAINED SPOTTER        

   EVERGREEN              5.0   905 AM  2/20  TRAINED SPOTTER        

   SPOUT SPRING           5.0  1013 AM  2/20  TRAINED SPOTTER        

   APPOMATTOX             4.0   908 AM  2/20  TRAINED SPOTTER        

 

...BATH COUNTY...

   MILLBORO               8.0   757 PM  2/19  TRAINED SPOTTER        

 

...BEDFORD COUNTY...

   3 WNW FOREST           7.4   810 PM  2/19  TRAINED SPOTTER        

   5 NW LYNCHBURG AIRPO   6.0   815 PM  2/19  BROADCAST MEDIA        

 

...BLAND COUNTY...

   1 N CERES              6.0   759 PM  2/19  TRAINED SPOTTER        

 

...BOTETOURT COUNTY...

   3 NNW DALEVILLE        5.8   900 PM  2/19  TRAINED SPOTTER        

   LAYMANTOWN             5.1   753 PM  2/19  PUBLIC                 

 

...BUCKINGHAM COUNTY...

   TOGA                   7.5   820 AM  2/20  EMERGENCY MNGR         

   BUCKINGHAM             7.0  1009 AM  2/20  CO-OP OBSERVER         

 

...CAMPBELL COUNTY...

   TIMBERLAKE             7.2  1050 PM  2/19  TRAINED SPOTTER         

   RUSTBURG               5.0   928 PM  2/19  LAW ENFORCEMENT        

 

...CARROLL COUNTY...

   4 ENE FRIES            6.5   916 AM  2/20  TRAINED SPOTTER        

   FRIES                  6.0  1203 AM  2/20  TRAINED SPOTTER        

   GLADESBORO             5.5   800 PM  2/19  AMATEUR RADIO          

   DUGSPUR                5.0   800 PM  2/19  TRAINED SPOTTER        

   CANA                   1.8   800 PM  2/19  AMATEUR RADIO          

 

...CHARLOTTE COUNTY...

   KEYSVILLE              5.0  1000 AM  2/20  CO-OP OBSERVER         

   CHARLOTTE COURT HOUS   4.0   937 PM  2/19  LAW ENFORCEMENT        

 

...CITY OF BEDFORD...

   BEDFORD CITY           6.0   824 PM  2/19  TRAINED SPOTTER        

 

...CITY OF DANVILLE...

   DANVILLE CITY          3.0  1200 AM  2/20  CO-OP OBSERVER         

 

...CITY OF GALAX...

   GALAX                  4.0   800 PM  2/19  AMATEUR RADIO          

 

...CITY OF LEXINGTON...

   LEXINGTON              7.0  1031 PM  2/19  PUBLIC                 

 

...CITY OF LYNCHBURG...

   LYNCHBURG CITY         7.7  1010 PM  2/19  WSET                   

 

...CITY OF MARTINSVILLE...

   MARTINSVILLE CITY      4.0   934 PM  2/19  TRAINED SPOTTER        

 

...CITY OF RADFORD...

   RADFORD                6.0   819 PM  2/19  TRAINED SPOTTER         

 

...CITY OF ROANOKE...

   ROANOKE                5.5  1200 AM  2/20  BROADCAST MEDIA        

 

...CRAIG COUNTY...

   2 ESE PAINT BANK       7.5   830 AM  2/20  PUBLIC                 

   NEW CASTLE             6.0   815 AM  2/20  LAW ENFORCEMENT         

 

...FLOYD COUNTY...

   4 SSE COPPER HILL      8.0   803 PM  2/19  TRAINED SPOTTER        

   CHECK                  7.5   809 PM  2/19  TRAINED SPOTTER        

   ALUM RIDGE             7.2   904 PM  2/19  TRAINED SPOTTER        

   2 N FLOYD              7.0   833 PM  2/19  EMERGENCY MNGR         

   MEADOWS OF DAN         6.0   833 PM  2/19  TRAINED SPOTTER        

 

...FRANKLIN COUNTY...

   4 NE ROCKY MOUNT       6.7   630 AM  2/20  BROADCAST MEDIA        

   BOONES MILL            6.0   800 AM  2/20  PUBLIC                 

   ROCKY MOUNT            6.0   800 AM  2/20  PUBLIC                 

   5 SSE BURNT CHIMNEY    4.0   843 PM  2/19  TRAINED SPOTTER        

   2 SW CALLAWAY          4.0   845 PM  2/19  TRAINED SPOTTER        

 

...GILES COUNTY...

   3 S EGGLESTON          6.0   806 PM  2/19  TRAINED SPOTTER        

   1 WNW BANE             4.6   800 PM  2/19  AMATEUR RADIO          

   1 ESE WHITE GATE       4.0   800 PM  2/19  AMATEUR RADIO          

 

...GRAYSON COUNTY...

   5 NE INDEPENDENCE      7.8   846 AM  2/20  TRAINED SPOTTER        

   ELK CREEK              7.0   237 AM  2/20  TRAINED SPOTTER        

   INDEPENDENCE           5.2   818 PM  2/19  LAW ENFORCEMENT        

   MOUTH OF WILSON        4.0   815 PM  2/19  TRAINED SPOTTER        

   BAYWOOD                3.5   800 PM  2/19  AMATEUR RADIO          

 

...HALIFAX COUNTY...

   CLOVER                 4.5   840 AM  2/20  LAW ENFORCEMENT        

   SOUTH BOSTON           4.5   840 AM  2/20  LAW ENFORCEMENT        

   3 SE RIDGEWAY          4.0   835 AM  2/20  LAW ENFORCEMENT        

   HALIFAX                3.0   838 AM  2/20  LAW ENFORCEMENT        

 

...HENRY COUNTY...

   2 NW BASSETT           3.0   843 PM  2/19  TRAINED SPOTTER        

 

...MONTGOMERY COUNTY...

   1 W PILOT              9.6   800 AM  2/20  TRAINED SPOTTER        

   2 S PILOT              9.4  1213 AM  2/20  TRAINED SPOTTER        

   2 WNW CHRISTIANSBURG   8.0   826 AM  2/20  TRAINED SPOTTER        

   ELLISTON               8.0   109 AM  2/20  PUBLIC                 

   2 ESE CHRISTIANSBURG   7.0   800 PM  2/19  AMATEUR RADIO          

   BLACKSBURG             7.0  1205 AM  2/20  TRAINED SPOTTER        

   CHRISTIANSBURG         6.7   900 PM  2/19  NWS EMPLOYEE           

   3 S CHRISTIANSBURG     6.5   230 AM  2/20  NWS EMPLOYEE           

   1 NW BLACKSBURG        6.5   800 PM  2/19  AMATEUR RADIO          

   MERRIMAC               6.0   836 PM  2/19  TRAINED SPOTTER        

 

...PATRICK COUNTY...

   10 NE STUART           5.0   730 AM  2/20  TRAINED SPOTTER        

   4 ESE BUFFALO RIDGE    4.5   856 PM  2/19  TRAINED SPOTTER        

 

...PITTSYLVANIA COUNTY...

   5 SE CHATHAM           6.0   833 AM  2/20  LAW ENFORCEMENT        

 

...PULASKI COUNTY...

   PULASKI                7.0   800 PM  2/19  AMATEUR RADIO          

   DUBLIN                 7.0   800 PM  2/19  AMATEUR RADIO          

   FAIRLAWN               6.3   800 PM  2/19  AMATEUR RADIO          

 

...ROANOKE COUNTY...

   CAVE SPRING            7.4   848 PM  2/19  TRAINED SPOTTER        

 

...ROCKBRIDGE COUNTY...

   5 N COLLIERSTOWN       9.0   900 PM  2/19  PUBLIC                 

   ROCKBRIDGE BATHS       7.8  1015 PM  2/19  TRAINED SPOTTER        

 

...SMYTH COUNTY...

   2 N MARION             4.8   747 AM  2/20  TRAINED SPOTTER        

 

...TAZEWELL COUNTY...

   RICHLANDS              5.5   900 PM  2/19  LAW ENFORCEMENT        

 

...WYTHE COUNTY...

   WYTHEVILLE             8.8   924 AM  2/20  TRAINED SPOTTER        

   1 NNW WYTHEVILLE       8.0  1007 PM  2/19  TRAINED SPOTTER        

   IVANHOE                6.0   749 PM  2/19  NWS OFFICE             

 

WEST VIRGINIA

 

...GREENBRIER COUNTY...

   4 SE RONCEVERTE        9.0   725 AM  2/20  TRAINED SPOTTER        

   LEWISBURG              9.0   800 PM  2/19  PUBLIC                 

   3 SE RENICK            8.5   950 PM  2/19  TRAINED SPOTTER        

 

...MERCER COUNTY...

   2 NE MONTCALM          9.0   818 PM  2/19  PUBLIC                 

   ATHENS                 7.0   845 AM  2/20  TRAINED SPOTTER        

   PRINCETON              7.0   945 AM  2/20  TRAINED SPOTTER        

   1 S BLUEFIELD          6.0   740 PM  2/19  TRAINED SPOTTER        

 

...MONROE COUNTY...

   1 NW LAUREL BRANCH     7.2  1009 AM  2/20  CO-OP OBSERVER         

   1 N PETERSTOWN         5.0   759 PM  2/19  PUBLIC                 

 

...SUMMERS COUNTY...

   HINTON                 5.5  1115 PM  2/19  TRAINED SPOTTER        

 



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