06 August 2004

0205	MCS is off scope (at least the convective region), the stratiform region is still nonly ~30km away. There are dying convective cells in the SE part of the scope. All in all, a great MCS case today! Probably good for gulf surge initiation.

0300	James Done arrives

0315	Switched to climofar to optimize data collection of the system as it moves off to the northwest of the radar site.

0400	A line of convective cells has triggered along a convergence line, possibly a cold-pool outflow from the exiting MCS, parallel to the coast about 70km off-shore. The 7.9deg beam topped the highest cell 100km away (14km high).

0430	Line if filling in (50dBZ) and it seems to be connected to a larger system now entering the southern radar domain over the Gulf. This new system triggered along the coast, south of the radar domain, and is now almost entirely over the Gulf.

0450	The line is now clearly connected to today's MCS event and is propagating away from the radar in an arc.

0545	Scattered convection now triggering behind the line of convection over the Gulf, closer to SPOL. Convergence signatures are present at all elevation angles (inc 0.0) - surface based?

0600	Weaker echoes (<30dBZ) now developing over the coastal plain and foothills in the 30-150degree sector.

0700	Switched back to climofar because I felt it was sacrificing good data collection of the main system and line for the sake of one close cell. 

0730	Cold pool boundaries evident on the 0.0degree sweep in dBZ and Vr propagating NNE from the leading line (45-50dBZ line). MCS now well into the southern half of the scope.

0745	Strangley, the scan sequence didn't start automatically. I caught it at 0748Z and manually restarted it. I lost the last 2 elevation angles ready for the 0800 scan.

0830	Light rain observed at the radar site. Still not switching to climonear because the main event is ~70-150km away and I'd like good vertical resolution.

0950	Reluctant to switch to microphysics sectors to capture the main system for fear of sacrificing other convection outside the sector.

1020	Convection no-longer exclusively confined to the leading edge and now convection extends to the tail edge of the amorphous MCS. Some evidence of rotating cells at lower levels (<4km).

1200	Sarah and Gustavo here.

1205	Small area of precip heading towards SPOL (not topped at 14 degrees, but Gustavo and James felt climofar was still better to keep vertical res, high for MCS in SW quadrant). The nearby convection is probably too close to worry about anyway (within 5-10km of SPOL).

1345	MCS appears to be dissipating (within last 30mins echo is weakening and decreasing in size). Visual obs indicate non-precipitating stratus continues to move over SPOL - will stay in climofar to catch end of MCS instead of Near to catch the weak echos near the radar (stratus).

1610	Things are clearing up on the radar screen. No echoes above 6.7degrees so will go to climo shallow.

1615	Switched to climoshallow

1745	Appears to be an MCV in western domain. We first noted the apparent rotation in the reflectivities of the MCS at the beginning of the shift, but it wasn't as clear in the velocities until more recently.

1800	Nesbitt and Bordoni here. In Climoshallow to get rapid scans of the MCV over the ocean. Some cells growing just offshore which may need a switch to climofar.

2045	Went to climofar MCV is off scope and convection topped to NE.

2115	Switch to MicroFar135 centered at 60 degrees to follow lifecycle of cells developing to East near SPOL. First sector scan at 50.5

2130	Had to resynch rainmap, as scan was running late. Again, doing RHI at 50.5, 46 degrees.

2210	RHI at 98.6 degrees.

2222	Doing RHI at 97.8 through >50dBZ core.

2250	Scans at 100.5 through strongest cell and stratiform region.

2300	Things are dissipating

2330	The SE portion of the stratiform region from convective cells is not completely covered by the 135deg sector. Recentering sector scan to 75degrees. (15 seconds late - will keep an eye on whether need to resynch at 2345). RHI at 103.8 degrees.

2345	Resynched - should be OK for next scan. RHI at 94.5degrees through bright-band.