CASE 22 - Oceanic MCS
moved into range during decay
Microphysical scans 1545 - 1730 Z, 1h
45m
SYNOPTIC CONDITIONS SUMMARY:
IV #10 has moved off the
W coast of Region
of low-level convergence along the SMO and to the SE of Mazatlan
(see image at left). 700 mb convergence line extending from
Day
0 forecast discussion text (in Spanish)
Winds
200
mb - model.ETA.200408091200.00_200mb_wnd.gif
- model.ETA.200408100000.00_200mb_wnd.gif
500
mb - model.ETA.200408091200.00_500mb_wnd.gif
- model.ETA.200408100000.00_500mb_wnd.gif
700
mb - model.ETA.200408091200.00_700mb_wnd.gif
- model.ETA.200408100000.00_700mb_wnd.gif
850
mb - model.ETA.200408091200.00_850mb_wnd.gif
- model.ETA.200408100000.00_850mb_wnd.gif
EVENT SUMMARY: Complex MCS formed off the coast of
24
h precipitation totals -
ROUGH
TIMELINE OF DEVELOPMENT:
|
1000
Z |
Convection
developing off the coast of 1009Z, GOES-10 Thermal IR
|
|
1200
Z |
Complex
MCS off the coast of 1154Z, GOES-10 Thermal IR
|
|
1300
- 1400 Z |
MCS
peaking - has complex structure, with 2 to 3 convective maxima regions. 1324Z, GOES-10 Thermal IR
1324Z, GOES-10
|
|
1400
- 1700 Z |
MCS
weakening. |
S-POL SUMMARY: S-Pol captured later stages of oceanic MCS, running
microphysical scans of northern end of system as it weakened.
SCAN
OVERVIEW:
|
1000
Z |
Fourth
generation outflow seen in 0.0 scan. Isolated cells forming off the 1000Z, Base reflectivity
|
|
1115
Z |
Nice
stratiform region extending north of fourth generation cells to the S. Now
merging with those isolated cells and intensifying. 1115Z, Base reflectivity
|
|
1200
Z |
Complex
MCS has developed over water near 1200Z, Base reflectivity
|
|
1245
Z |
Switching to ClimoNear:
Cells rapidly approaching radar.
Cell 60 km S of radar has 30 dBZ at 14 deg. Tough
compromise with ClimoFar because convection extends
beyond 150 km. Looks like flow has backed around to SEly
at low levels. 1245Z, Base reflectivity
|
|
1413
Z |
MCS
continues to slowly creep northward. Convective region is oriented NW-SE with
stratiform region blowing off to SW. Convective cells appear very
"cellular" vs. being one solid continuous region. Appears that new
cell development is favored on the NE side of the convective region. New
cells forming just to the west of S-Pol at the
moment. Interesting convective "streamer" pattern from these cells.
In the velocity pattern there appears to be a large MCV associated with this
system within the stratiform region. Movement of MCV is nearly stationary at
the moment, or maybe slightly south? 1415Z, Base reflectivity
1415Z, Base radial velocity
|
|
1538
Z |
PRF Switched to1000 Hz, Begin Ka
Band: Rain rain
maps @ 720 Hz, then stopped antenna & switched to 1000 Hz (Ka band).
Restarted "Shallow960" - which is like ClimoNear
with 8 deg/sec rotation rate. Will try to gauge timing and optimize. |
|
1545
- 1630 Z |
Begin Microphysical Scanning, Ad-Hoc
Scanning / MicroMCS360: 1545 - Resynched, did RHIs at 220,
195, 180, 135, 90, 75, at angles > 135 2x. 1600 - Resynched
- noted clutter filter is off by default and must be reenabled
in 1000 Hz PRF. 1615 - Ran scan
with 1 km vert resolution between 30-50 km. 1630 - Resynched - Enhanced ClimoNear
elevations in Shallow960 - added 2.5, 4.5, 6.5. Will do one set of RHIs at the end. We'll see on timing 1545Z, Base reflectivity
1615Z, Base reflectivity
|
|
1640
Z |
Getting
some great Ka band observations of 40 dBZ S-(35 dBZ Ka-)band bright band. |
|
1700
Z |
Stratiform
region beginning to fall apart near S-Pol.
Convection has fired to west over Gulf of Calif. May be worth considering
changing back to low PRF to capture further away evolution as interest has
shifted away from close ranges. Interesting embedded shallow convection with
fall streaks to WSW of radar. 1700Z, Base reflectivity
|
|
1730
Z |
End Microphysical Scanning, Switched
back to ClimoFar (720 Hz PRF): Stratiform
nearby falling apart and convection from MCS getting going at > 150 km
range to west. Note: Saved MicroMCS360
scan to have next time 360s needed close to radar. It does: 0.8, 1.3, 2.5,
3.2, 4.5, 5.8, 7.1, 8.5, 11.1, 13.8, 16.4, 18.9, 21.5, 23.9, 26.4, and one
RHI set. |
