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Synoptic
Overview –
A vigorous mid-level trough moved from the northern Plains April 27 to the Western Great Lakes by 12Z on April 28, 2011 (Figure 2). This advancing system was responsible for the worst tornado outbreak in the United States since 1974 with over 100 tornadoes and over 300 deaths reported on April 27. As a result of the previous day’s tornado outbreak, awareness was high for tornadoes over the Region. As this system advanced eastward on the morning of April 28, deep moisture was advected north at 850 mb (Figure 3) with a 60 knot jet maximum poised just west of the area at 12Z. At the surface, a cold front pushed slowly across the state and was approaching from central North Carolina at 21Z (Figure 4), with very moist air over eastern North Carolina with dewpoint temperatures in the lower and middle 70s. Deep layer south to southwest wind shear and CAPE (Convective Available Potential Energy) values of 1000 to 2000 j/kg were enough to overcome the relatively weak mid level lapse rates. The 12Z Newport/Morehead City sounding (Figure 5) showed conditions favorable for tornadic development with 0 to 1 kilometer helicity values of 287 m2s2, and a right-turning hodograph indicative of strong low-level wind shear. Conditions also favored large hail with the wet bulb zero height around 9570 feet.
The initial tornado report was from Warsaw in
southwestern Duplin County and came in shortly after 3 pm (19Z) with the MHX radar
showing strong rotation at the lowest levels (Figure 6). This same supercell
thunderstorm would continue to the northeast and produce another tornado
touchdown near Fort Barnwell in Craven County (Figure 7). A supercell that formed to the east of this storm would
later produce a tornado with minor damage over Plymouth in Washington
County.

Figure 2. 500
mb Analysis at 12Z April 28 showing a broad mid-level trough advancing
east.

Figure 3. 850
mb Analysis at 12Z April 28 showing warm moist air being drawn northward
into eastern North Carolina with a 60-knot jet maximum approaching from the
west.

Figure 4.
Surface Analysis at 21Z showing cold front approaching from the west. Dewpoints were in the 70s over Eastern North Carolina
ahead of the front.

Figure 5. The
12Z Newport/Morehead City Sounding showed conditions favorable for tornadic and large hail development on April 28.

Figure 6.
Newport/Morehead City Doppler radar indicated two areas of intense rotation
over Duplin County shortly after 3 pm April 28. Warsaw in Western Duplin
County, northwest of Kenansville reported the first tornado touchdown of
the day.

Figure 7.
Newport/Morehead City Doppler radar indicated strong but broad rotation
over northern Craven County around 430 pm April 28.
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL
WEATHER SERVICE NEWPORT/MOREHEAD CITY NC
1211 PM
EDT FRI APR 29 2011
..TIME... ...EVENT... ...CITY
LOCATION...
...LAT.LON...
..DATE... ....MAG.... ..COUNTY
LOCATION..ST..
...SOURCE....
..REMARKS..
0252
PM TSTM WND
DMG
TEACHEY
34.77N 78.01W
04/28/2011
DUPLIN
NC PUBLIC
SEVERAL TREES DOWN. TIME ESTIMATED BY RADAR.
0301
PM TSTM WND
DMG 5 SE MAGNOLIA
34.84N 77.99W
04/28/2011
DUPLIN
NC FIRE
DEPT/RESCUE
TURKEY BARNS AND OUTBUILDINGS DAMAGED. TREES DOWN. NEAR
NC903 AND HALLS POND RD.
0310
PM
TORNADO
8 SE WARSAW 34.92N 77.99W
04/28/2011
DUPLIN
NC EMERGENCY
MNGR
HOG FARM AND TREES SNAPPED IN A 150 TO 200 FT WIDE PATH
APPROX 0.5 MILES LONG.
0343
PM HAIL
1 N FARMVILLE
35.61N 77.59W
04/28/2011 E0.75 INCH
PITT
NC TRAINED SPOTTER
0345
PM HAIL
1 N PINK HILL
35.07N 77.74W
04/28/2011 E1.00 INCH
LENOIR
NC PUBLIC
0415
PM TSTM WND
DMG 3 SE
WILLIAMSTON
35.82N 77.02W
04/28/2011
MARTIN
NC PUBLIC
TWO TREES DOWN ON A SHED ON BELLTOWN RD. TIME ESTIMATED
BASED ON RADAR.
0435
PM HAIL
3 NE VANCEBORO 35.34N 77.12W
04/28/2011 E2.75 INCH
CRAVEN
NC EMERGENCY
MNGR
0435
PM TSTM WND
DMG 1 E FORT
BARNWELL
35.27N 77.31W
04/28/2011
CRAVEN
NC EMERGENCY
MNGR
TREES AND POWERLINES DOWN ON BELLTOWN ROAD.
0440
PM HAIL
1 SE WILMAR
35.39N 77.14W
04/28/2011 E1.00 INCH
CRAVEN
NC PUBLIC
RELAYED FROM 911 CENTER
0500
PM
TORNADO
PLYMOUTH
35.86N 76.75W
04/28/2011
WASHINGTON
NC PUBLIC
TREE DOWN ON GARAGE. TIME ESTIMATED BY RADAR.
0500
PM
TORNADO
PLYMOUTH
35.86N 76.75W
04/28/2011
WASHINGTON
NC PUBLIC
TREE DOWN ON PORCH ON MAIN ST.
0506
PM TSTM WND
DMG
PLYMOUTH
35.86N 76.75W
04/28/2011
WASHINGTON
NC PUBLIC
POWERLINES DOWN ON CHERRY ST
0530
PM TSTM WND
DMG
WENONA
35.73N 76.63W
04/28/2011
WASHINGTON
NC LAW ENFORCEMENT
TREES DOWN ON PIKE ROAD IN ADDITION TO 1 INCH HAIL
0620
PM FUNNEL
CLOUD 3 SSW
COLUMBIA
35.88N 76.27W
04/28/2011
TYRRELL
NC LAW ENFORCEMENT
REPORTED OVER NEWLANDS ROAD HEADING NE TOWARD COLUMBIA.
RELAYED FROM 911 CENTER
&&
Sources –
Storm Prediction Center
GR2 Analyst Software
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