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| Storm Reports |
| Are you interested in what happened during a recent event? Check out the report below. |
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Severe Storms/Very Windy on December 19-20, 2012 |
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A powerful storm system tracked from the Texas panhandle into Missouri on the 19th. It was cold enough for snow and blizzard conditions to the north and west of the system, with milder air and a chance of severe thunderstorms in Arkansas.
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| In the picture: There was a complex weather pattern early on 12/20/2012. Snow and blowing snow existed north and west of a storm system ("L") in western Missouri, with strong to severe thunderstorms farther south and east. |
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Thunderstorms fired during the evening in eastern Oklahoma and tracked into western Arkansas. Storms were just ahead of a cold front extending southward from the system in Missouri.
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| In the picture: The WSR-88D (Doppler Weather Radar) showed a variety of precipitation types across the middle of the country at 1038 pm CST on 12/19/2012. |
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The strongest storms tended develop in southern sections of the state where the atmosphere was the most unstable (warmest temperatures and available moisture). Given a lot of wind energy aloft, storms were driven to the east quickly.
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One line of storms in particular rocketed through several southern counties at more than 50 mph.
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| In the picture: The WSR-88D (Doppler Weather Radar) showed a bowing segment tracking from Arkadelphia (Clark County) toward Sheridan (Grant County) at 104 am CST on 12/20/2012. The bowing was caused by damaging winds punching into a line of storms from behind. |
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The storms produced 60 to more than 80 mph gusts from Murfreesboro (Pike County) to Arkadelphia (Clark County), Donaldson (Hot Spring County), Sheridan (Grant County), White Hall (Jefferson County) and DeWitt (Arkansas County). Numerous trees and power lines were downed along the way, with roads blocked by fallen trees. At least three barns were blown away south of Delight (Pike County).
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On the north end of the line, a brief weak tornado (rated EF1) was spawned a few miles west of Sheridan (Grant County). A mobile home was destroyed, with shop buildings damaged and trees snapped. Several minor injuries were reported.
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| In the picture: The WSR-88D (Doppler Weather Radar) showed some rotation nearing Sheridan (Grant County) from the southwest at 125 am CST on 12/20/2012. The rotation was on the northern end (or bookend) of a bowing segment (backward C-shaped line of storms). |
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Another weak tornado (rated EF1) was confirmed northeast of Lavaca (Sebastian County). A couple of mobile homes were hit, with one dismantled. Roofs were ripped from chicken houses and a fire station was also damaged.
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Isolated tornadoes were not a surprise during this event. Winds went from southeast at ground level to south and southwest at 5000 feet. The change in direction with height created a turning motion in some storms, and tornadoes resulted.
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| In the picture: Winds turned with height during the evening of 12/19/2012. At the surface (in red), winds were from the south to southeast, with south to southwest winds at 850 mb or 5000 feet (in green) and southwest winds at 700 mb or 10000 feet (in blue). Shear values from 0-1 km were extremely high locally, with values close to 700 m2/s2. This made isolated tornadoes possible. |
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Elsewhere, quarter to half dollar size hail and 60 to 65 mph gusts were reported at Chismville and Caulksville (both in Logan County). Trees were toppled in parts of Scott County, with a roof damaged at a home in Hagarville (Johnson County). Across the region, power was out to more than 40,000 customers.
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Cars left outside were coated in mud. That is because dust from drought stricken areas in the southern Plains was ingested by the aforementioned storm system, and "dirty rain" fell from the sky. Because storms moved so fast, precipitation did not last long and amounts were generally an inch or less.
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| In the picture: The satellite showed clouds streaming from southwest to northeast across the central and southern Plains, with dust kicking up in western Texas during the morning of 12/19/2012. This was ahead of an intensifying storm system moving eastward from the Rockies. |
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By 600 am CST on the 20th, the front was in eastern sections of the state. Behind the front, winds shifted to the west to northwest, and gusted to more than 40 mph. Temperatures fell quickly into the lower 30s in northwest Arkansas. There was enough moisture for a few snow flurries at Fayetteville (Washington County) and Harrison (Boone County). Meanwhile, readings were in the 50s ahead of the front along the Mississippi River.
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Winds were the big story on the 20th statewide. |
| In the picture: Six hour pressure changes from 600 pm CST on 12/19/2012 to 1200 am CST on 12/20/2012. Initially, there were pressure falls in Arkansas...with upward motion to create clouds and thunderstorms. Strong pressure rises (17 millibars/6 hours) were not far behind in the Plains, with sinking motion and much colder/more stable air. Between falls and rises, there was an extreme isallobaric (pressure tendency) gradient...and a promise of a lot of wind across the region. |
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Winds continued from the west/northwest at 25 to 35 mph, and gusts exceeded 50 mph in places.
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| Highest Wind Gusts on 12/20/2012 |
| Site |
Gust (MPH) |
Time (CST) |
| Fayetteville (NW AR) |
55 |
0712 am |
| Harrison (NC AR) |
47 |
1111 am |
| Jonesboro (NE AR) |
53 |
0955 am |
| Fort Smith (WC AR) |
51 |
0403 am |
| Little Rock (C AR) |
49 |
1019 am |
| West Memphis (EC AR) |
44 |
0852 am |
| Texarkana (SW AR) |
46 |
0530 am |
| El Dorado (SC AR) |
41 |
0654 am |
| Pine Bluff (SE AR) |
47 |
0641 am |
| There were several reports of damaging winds, hail and a possible weak tornado on December 19-20, 2012. For a look at some reports, click here.
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| In the picture: Preliminary reports of severe weather in the Little Rock County Warning Area on December 19-20, 2012 (in red). |
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