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Fic. 2. Schematic of BAMEX facility deployment. The rapid scanning capability of the Electra Dop- pler radar (ELDORA) on the NRL P-3 made it ideal to scan the convective region of MCSs, mapping the kinematic structure of the leading convective line and the rear-inflow current immediately behind the line (to the extent allowed because of attenuation). The

Figure 2 Fic. 2. Schematic of BAMEX facility deployment. The rapid scanning capability of the Electra Dop- pler radar (ELDORA) on the NRL P-3 made it ideal to scan the convective region of MCSs, mapping the kinematic structure of the leading convective line and the rear-inflow current immediately behind the line (to the extent allowed because of attenuation). The

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It was convenient to distinguish observational strategies for mature MCSs (whether a bow echo or not) from those for remnant MCVs, the latter asso- ciated with diminishing or scattered precipitation. In Fig. 2 we depict ideal system-relative aircraft flight tracks and ground-based facility deployment for these two scenarios. For MCS missions (Fig. 2a), the objec- Taste |. BAMEX facilities, principal investigators (Pl), and usage during the project.
It was convenient to distinguish observational strategies for mature MCSs (whether a bow echo or not) from those for remnant MCVs, the latter asso- ciated with diminishing or scattered precipitation. In Fig. 2 we depict ideal system-relative aircraft flight tracks and ground-based facility deployment for these two scenarios. For MCS missions (Fig. 2a), the objec- Taste |. BAMEX facilities, principal investigators (Pl), and usage during the project.
Fic. 3. Locations of dropsondes during BAMEX, color coded by IOP. Black star indicates location of MidAmerica St. Louis Airport. Black ellipse rep- resents 600-km-range ring around MidAmerica St. Louis Airport. The number of dropsondes is lower than that reported in Table | because not all dropsondes reported position.
Fic. 3. Locations of dropsondes during BAMEX, color coded by IOP. Black star indicates location of MidAmerica St. Louis Airport. Black ellipse rep- resents 600-km-range ring around MidAmerica St. Louis Airport. The number of dropsondes is lower than that reported in Table | because not all dropsondes reported position.
Tas_e 2. Summary of phenomena sampled during BAMEX IOPs and other significant missions. X’s indicate type of system. Red X’s indicate MCVs within which new convection was initiated. Blue X’s indicate severe bow echoes with widespread damaging winds. Green X’s indicate dissipating MCSs. Numbers in parentheses list observing platforms that sampled each case; | = GBOS; 2 = NRL P-3; 3 = NOAA P-3; 4 = Learjet with dropsondes; 5 = damage survey. For locations, AR = Arkansas, KY = Kentucky, IA = lowa, IN = Indiana, IL = Illinois, KS = Kansas, MO = Missouri, MN = Minnesota, MS = Mississippi, NE = Nebraska, OH = Ohio, SD = South Dakota, TN = Tennessee, and TX = Texas. The MCS during IOP 7 formed over northeast Nebraska around 0000 UTC 10 June (Fig. 4). It evinced a double-bow structure early in its evolution (e.g., 0300 UTC; Fig. 4), consolidating later to a con- tinuous line, though still retaining bowed segments (0600 UTC; Fig. 5a). According to severe storm re- ports archived by the Storm Prediction Center, and confirmed by extensive damage surveys conducted by BAMEX personnel, a concentrated area of wind dam- age occurred near Emerson, Nebraska (near Sioux City, Iowa), with the small bow-echo segment to the northeast around 0130 UTC. Additional damage oc- curred in and around Shelby, Nebraska (southeastern Nebraska), with the southwestern-bowed segment between 0100 and 0400 UTC. Typical maximum es- timated surface winds were 30-35 m s'. Damage oc-
Tas_e 2. Summary of phenomena sampled during BAMEX IOPs and other significant missions. X’s indicate type of system. Red X’s indicate MCVs within which new convection was initiated. Blue X’s indicate severe bow echoes with widespread damaging winds. Green X’s indicate dissipating MCSs. Numbers in parentheses list observing platforms that sampled each case; | = GBOS; 2 = NRL P-3; 3 = NOAA P-3; 4 = Learjet with dropsondes; 5 = damage survey. For locations, AR = Arkansas, KY = Kentucky, IA = lowa, IN = Indiana, IL = Illinois, KS = Kansas, MO = Missouri, MN = Minnesota, MS = Mississippi, NE = Nebraska, OH = Ohio, SD = South Dakota, TN = Tennessee, and TX = Texas. The MCS during IOP 7 formed over northeast Nebraska around 0000 UTC 10 June (Fig. 4). It evinced a double-bow structure early in its evolution (e.g., 0300 UTC; Fig. 4), consolidating later to a con- tinuous line, though still retaining bowed segments (0600 UTC; Fig. 5a). According to severe storm re- ports archived by the Storm Prediction Center, and confirmed by extensive damage surveys conducted by BAMEX personnel, a concentrated area of wind dam- age occurred near Emerson, Nebraska (near Sioux City, Iowa), with the small bow-echo segment to the northeast around 0130 UTC. Additional damage oc- curred in and around Shelby, Nebraska (southeastern Nebraska), with the southwestern-bowed segment between 0100 and 0400 UTC. Typical maximum es- timated surface winds were 30-35 m s'. Damage oc-
Fic. 4. lsochrones of solid convective lines with maximum reflectivity > 45 dBZ (solid), broken or dissipating lines (dashed), and MCV posi- tions (Xs) for three IOPs. Blue denotes IOP | (24 May 2003), black denotes IOP 7 (9-10 Jun 2003), red-orange denotes IOP 12 (24 Jun 2003), and green denotes 10-11 June St. Louis bow echo. Times are UTC in 3-h intervals. The convention HH/DD is used to indicate se- lected dates. ally southwesterly flow, it tracked eastward rather than southeastward (Fig. 4). This event featured co- ordination of the NRL P-3, Learjet, and GBOS. The NOAA P-3 experienced a fuel leak and was forced to abort its mission. Exceptionally good data from ELDORA were obtained as the NRL P-3 traversed the area ahead of a bowed segment in the line (Fig. 7). A maximum outflow exceeding 35 m s was observed around 0630 UTC 24 June.
Fic. 4. lsochrones of solid convective lines with maximum reflectivity > 45 dBZ (solid), broken or dissipating lines (dashed), and MCV posi- tions (Xs) for three IOPs. Blue denotes IOP | (24 May 2003), black denotes IOP 7 (9-10 Jun 2003), red-orange denotes IOP 12 (24 Jun 2003), and green denotes 10-11 June St. Louis bow echo. Times are UTC in 3-h intervals. The convention HH/DD is used to indicate se- lected dates. ally southwesterly flow, it tracked eastward rather than southeastward (Fig. 4). This event featured co- ordination of the NRL P-3, Learjet, and GBOS. The NOAA P-3 experienced a fuel leak and was forced to abort its mission. Exceptionally good data from ELDORA were obtained as the NRL P-3 traversed the area ahead of a bowed segment in the line (Fig. 7). A maximum outflow exceeding 35 m s was observed around 0630 UTC 24 June.
Fic. 6. Cross section from 10 Jun bow echo (see Fig. 5b) produced from quad-Doppler analysis. Shown are system-relative winds and reflectivity (dBZ) in the vertical plane. cells formed in central Missouri. By 2100 UTC, the area had formed a short, severe convective line
Fic. 6. Cross section from 10 Jun bow echo (see Fig. 5b) produced from quad-Doppler analysis. Shown are system-relative winds and reflectivity (dBZ) in the vertical plane. cells formed in central Missouri. By 2100 UTC, the area had formed a short, severe convective line
(Fig. 4) that began moving rapidly eastward toward St. Louis. Hail as large as 4 cm in diameter was re- ported with the developing convective line. The line became oriented in a north-south direction and ac- celerated to a ground relative speed of about 35 ms™. According to a special 1800 UTC sounding from Springfield, Missouri (about 100 km south of the lo- cation where the first cells developed), the wind was westerly or southwesterly at all levels with a vertical wind shear of about 15 ms"! between the surface and 700 hPa and weak shear between 700 and 250 hPa. Data from the 404-MHz NOAA profiler at Conway, Missouri (about 50 km to the northeast of Spring-
(Fig. 4) that began moving rapidly eastward toward St. Louis. Hail as large as 4 cm in diameter was re- ported with the developing convective line. The line became oriented in a north-south direction and ac- celerated to a ground relative speed of about 35 ms™. According to a special 1800 UTC sounding from Springfield, Missouri (about 100 km south of the lo- cation where the first cells developed), the wind was westerly or southwesterly at all levels with a vertical wind shear of about 15 ms"! between the surface and 700 hPa and weak shear between 700 and 250 hPa. Data from the 404-MHz NOAA profiler at Conway, Missouri (about 50 km to the northeast of Spring-
tions in the microphysical properties of the spirals in context of the meteorological situation and distance from the bow in order to understand and quantify the role of aggregation, melting, and evaporation in the melting layer on the evolution of bow echoes.
tions in the microphysical properties of the spirals in context of the meteorological situation and distance from the bow in order to understand and quantify the role of aggregation, melting, and evaporation in the melting layer on the evolution of bow echoes.
Fic. 11. Damage survey from 10 Jun 2003 severe bow echo near MidAmerica St. Louis Airport. Blue shading denotes straight-line winds with damage equivalent to FO. Green arrows indicate wind direction inferred from debris orientation. Individual tornado tracks are denoted by heavy red lines. Time of damage ranged from about 2300 UTC 10 Jun to 0000 UTC II Jun. Domain is box with dashed line in Fig. 10.
Fic. 11. Damage survey from 10 Jun 2003 severe bow echo near MidAmerica St. Louis Airport. Blue shading denotes straight-line winds with damage equivalent to FO. Green arrows indicate wind direction inferred from debris orientation. Individual tornado tracks are denoted by heavy red lines. Time of damage ranged from about 2300 UTC 10 Jun to 0000 UTC II Jun. Domain is box with dashed line in Fig. 10.
Fic. 12. Images from the 2D-C probe during an advect- ing spiral descent behind a bow echo on 29 Jun 2003 displayed as a function of temperature. Each row is 1.6 mm from top to bottom.
Fic. 12. Images from the 2D-C probe during an advect- ing spiral descent behind a bow echo on 29 Jun 2003 displayed as a function of temperature. Each row is 1.6 mm from top to bottom.
Fic. 14. Space-time-corrected analysis of dropsonde and wind profiler data at 600 hPa for the MCV of IOP I. Winds are system relative; long barbs denote wind speed of 5 ms'; short barbs denote wind speed of 2.5 m s-'. Temperature (orange) is analyzed in 0.5°C increments; relative humidity (green) is analyzed in in- crements of 10%. Effective valid time is 1900 UTC 24 May 2003. Fic. 13. Mesoscale convective vortex observed by vis- ible satellite (NOAA-14 polar orbiter) at 1950 UTC 24 May (IOP 1). Black and white arrows schematically depict vortex-relative winds. Blue arrow indicate sys- tem trajectory. Orange dots mark dropsonde locations. “XX”? marks the vortex center. Large vorticity extends westward along the thin solid line.
Fic. 14. Space-time-corrected analysis of dropsonde and wind profiler data at 600 hPa for the MCV of IOP I. Winds are system relative; long barbs denote wind speed of 5 ms'; short barbs denote wind speed of 2.5 m s-'. Temperature (orange) is analyzed in 0.5°C increments; relative humidity (green) is analyzed in in- crements of 10%. Effective valid time is 1900 UTC 24 May 2003. Fic. 13. Mesoscale convective vortex observed by vis- ible satellite (NOAA-14 polar orbiter) at 1950 UTC 24 May (IOP 1). Black and white arrows schematically depict vortex-relative winds. Blue arrow indicate sys- tem trajectory. Orange dots mark dropsonde locations. “XX”? marks the vortex center. Large vorticity extends westward along the thin solid line.
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