An Upper Cold Pool (UCP) that moved over the southeastern quarter of Queensland; caused Spring Storms with reports of intense downpours with isolated reports of hail and spectacular lightning.
After a very dry August. It painted a drier than normal picture for spring. Rockhampton started Wednesday with a mild 15.7C minimum and a sunny morning. Then for the first time this season white fluffy impressive deep convective cumulus clouds began to develop very quickly around midday.
One cell a good 10 km across sat over the Berserkers showing signs of what was to come later in the day. This was heralded by one or two isolated thunder rolls around 4pm Tuesday afternoon from High Basted Thundery (HBT) development.
Then same again Wednesday afternoon as the thunder lasted longer with a light fall of a few large drops around 4.30pm Wednesday. By late afternoon isolated convective cells dotted the sky across CQ.
One report from Emerald had a light thundery shower with pea sized hail at 3.16pm.
Then a trough developed about the Capricorn/ Central Highlands Border with High Based Thundery Showers (HBTS) gathering together from Westwood to Calliope.
Brian from Mt Morgan called around 8pm saying after a lot of thunder he had a good storm with steady rain which lasted a good half hour with 21mm total; after a small fall earlier.
Then the trough moved east reaching Rockhampton with thunder and rain at 8.56pm at Ward Street with an intense fall; lasting to about 9.05pm. Checked my rain gauge – 7mm. Then it eased and finished about 9.14pm with a total of 8mm.
The storm moved to Nankin with Mike recording 17mm and the radar suggesting a chance of hail on the Emu Park Road. The cell seemed to move along the road to Tungamull before dying near the turn-off to the Croc Farm.
Some of the totals (mm) – Upper Ulam 39, Boolaroo Tops 28, Broadmeadows 20, Arcadia Valley 19, Mundic Gully 19, Mt. Larcom 18, Dedar Vale (18), Dary Ck. 16, Mid Kroombit 16, Mt Ogg 15, Mt. Mongrel 15, Raglan 14, Duaringa 14, Lake Brown 13, Upper Dee 13, Besch’s 12, Red Hill 11, Frenchville School 11, Bingegang 11, Westwood 10, Briggs 9, Table Tops 8, Castlehope 8, Upper Lonesome 7, Gladstone 6, Marlborough 5, Penlington 5, Bishop 5, Consuelo 5, Wowan 5, Goovigen 4, Mt. Bridget 4, Emerald 2. Very patchy with the spring storm scenario. Had a report of 4cm hail in Murwillumbah NSW as the UCP affected northern NSW. Some 7 day totals (mm) for Queensland – Upper Ulam 44, Mt. Sophia 44, low isles 40, Gympie 36, Tully 30, Nambour 29, Beerburrum 28, Nankin 22, Cairns 19, Brisbane 14.
With the Super Blue Moon and the lightning made it a spectacular start to Spring. In the south the snow melted on the Alps and Perth recorded its hottest winter’s day with a maximum of 29.7C on the 31st August. The SOI after dipping to -13 in early August rose slowly to -8 about the 28th August. Then it dropped to -11 for the 1st Sept. . There was a bit of hope and now it’s turned.
INTERNATIONAL
HONG KONG – China has issued its highest warning ” red” as Typhoon SAOLA about 300km southeast of Guangdong early Thursday. With winds gusts 240kph lowered to around 200kph it is expected to make a dramatic impact on Friday and Saturday near Hong Kong.
PACIFIC – Typhoon KIROGI well out in the Pacific may come close to southern Japan Monday.
USA – Hurricane Idalia crossed the coast as a Cat 3 at Keaton Beach Florida 7.45am Wednesday. Two deaths and many trees down and roofs with gusts 160kph and floods as storm surge reached 9 ft in its wake. Now it quickly passes into the Atlantic to meet up with Hurricane Franklin.
TAIWAN – Tropical Storm Haiku is about 1000km east of Taiwan. It is expected to reach Typhoon status and come close to Taiwan Thursday or Friday.
FORECAST
The large longitudinal high with a centre of 1028 hPa (see map) over Adelaide is pushing colder air over Melbourne. Expecting a maximum of 15C Friday.
Opening up the pressure gradient over most of the northern half of Queensland.
This means lighter winds and good conditions for the boaties.Just the afternoon NE Sea Breeze may kick up with gusts over 15 knots or 27kph in the mid to late afternoon (may get to 37kph?). Had a report of a good fog from Benaraby to Yeppoon early Friday.
This might be a feature in the coming mornings.
Maximums should be around 30C most of the week with humid days and minimums 12-14C . Now the tough question?
When will the chance of a HBTS occur? My understanding is mainly south of Gladstone to Brisbane from late afternoon Sunday onwards.
The River City to Bilo is a chance Sunday/Monday. Then maybe again Wednesday.
