Thunder
Downunder 2001!
November 24, 2001
Back to Thunder Downunder 2001 Chase Reports This day was looking like it was going to have more potential, and with the good convection on the previous day, then today could only get better! There was a broader and stronger area of instability, but that was mostly from the legacy of moisture left over from the thunderstorm activity on the day before. A broad area of -4 to -6 LIs existed, the forecast was for similar but with pockets of -6 to -8 LI, this may have happened locally - the analysis these charts were collected from have a poorer resolution.
Shear was increasing too, although stronger to the south with a jet well in excess of 100 knots. Over our area it was 60-65 knots, but that is still ample in these situations! Low level shear was very similar to the day before, with 10-15knots at 850, getting up to 30-40 knots at 500mb.
However cloud was building, so that was going to be a problem if it moved over - but it didn't, it stayed further to the south! The cloud essentially followed the jetstream, so this was perhaps a blessing in disguise not to have the best upper level winds over us, although storms did fire in NE NSW and the NW Slopes and Plains.
The trough had become more defined overnight, with a southerly pushing in behind it. The upper levels at 500mb had warmed up marginally, but that was in response to a weak upper trough pushing in behind the trough.
A weak 300mb trough was also present in the area - perhaps allowing storms to get a little higher on this day and become more electrically charged.
The 850 temperatures had cooled a fair amount, and with the additional moisture, the cap was significantly weaker, so storms fired much earlier - but were very persistent, and MCS-like convection exploded over much of the central southern area of Queensland during the day and well into the night, eventually reaching the coast the following morning!
Above - convection firing along the line at 1pm, below - convection exploding by 3pm.
Above - convection still firing along the line at 4pm with large clusters starting to join together, below - widespread convection and clusters joining together.
Report by Anthony Cornelius & Andrew McDonald, all captures by Andrew McDonald |
