CASE 31 - Mature to decaying stages of a weakly organized system that developed 100km N of S-Pol


Microphysical scans 1400 - 1615 Z, 2h 15m







Tier 1 under northwesterly upper flow regime - rare for mid-August.


NWly flow did not appear to alter the convective cycle over Mexico.


Day 0 forecast discussion text



200 mb - model.ETA.200408171200.00_200mb_wnd.gif

500 mb - model.ETA.200408171200.00_500mb_wnd.gif

700 mb - model.ETA.200408171200.00_700mb_wnd.gif

850 mb - model.ETA.200408171200.00_850mb_wnd.gif




MESOSCALE SUMMARY: A convective system developed out of range of S-Pol to the NW at ~0930Z, propagated vert slowly to the SE. System peaked around 1130 Z, continued to dissipate. Around 1345Z, new development was triggered to the SW of the dissipating system (over the GOC), at ~100 km to the N/NW of S-Pol. This cell intensified over the GOC, moving almost due S, until it dissipated by ~1600Z.


1424Z, GOES-10 Vis


24 h precipitation totals -




S-Pol log - spol_081704.txt




0600 - 1230 Z

Convective activity has been flaring and redeveloping to the N/NW of S-Pol beyond 140 km.


0830Z, Base reflectivity


1245 Z

Switching to ClimoFar: System to the N looks more convective.


1245Z, Base reflectivity


1300 Z

Cell at 300 deg at ~100-120 km intensifying. Core of 45 dBZ extends to 14 km.


1300Z, Base reflectivity


1400 Z

Begin Microphysical Scanning, Switching to MicroFar90: Centered on cell to the W/NW at 100 km range. Cell approaching 55 dBz at 1.98 deg elev angle. Large anvil blowoff.


1400Z, Base reflecitivity


1445 Z

Recentered sector at 280 deg. Storm is moving due S, currently E of S-Pol at 70 km. Mid 50ís dBZ and signature of ZDR column.


1445Z, Base reflectivity



Storm is decaying, but there is new intensification just north of the original cell. Still a large cirrus shield. Still in MicroFar90 centered on 280deg.


1515Z, Base reflectivity



System has pretty much died, but for now we will remain in microphysical mode incase things reintensify. Will reevaluate in about 30 minutes.


1530Z, Base reflectivity


1615 Z

End Microphysical Scanning, Switching to ClimoFar: Remnants to the E are dissipating, only anvil left.


1615Z, Base reflectivity