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May happenings

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I was away for all of may and have no real documentation for the month. I do, however know that on arrival home a nice 85mm was in my gauge. Unfortunately by some irony the WX software locked up 24 hours after we left and this compounds my lack of data for this period. I do know that over 150mm fell in a few days over the higher Mt Lofties including almost 90mm in 24 hours at these locations. In following the usual pattern of more mediocre falls the Meadows district highest 24 hour drop was closer to a modest 45mm. In the strong stream that exists just south of my location a high 75mm in 24 hours was recorded near Prospect Hill. This is just 7km south of me!! The good stuff falls all around and as usual its piggy in the middle for my place.

This was however the only event of significance for the month and probably the most significant event for the year to date. Rainfall deficets to the end of may are worrying and are a good 2 inches behind the eight ball. Another bad year?

11-06-08 Squall Line

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Late in the afternoon of the 11th a nasty looking squall line developed between 2 weak fronts.A long thin and fast moving but somewhat intense squall line developed and arrived on our doorstep at dusk. Lightning activity was showing on the trackers and it was with this in mind that I roared home from work and went straight to the hill in time to see, in the failing light, a long line of low intensly black cloud with an impenetrable rain base approaching. The odd flash of lightning could be seen reflecting through the rain and cloud tops that increased as it hit the coastline. Winds were nasty. Savage gusts rocking the car as I sat inside. This made getting decent pics really impossible. Wind is definitey the enemy causing nasty camera shake, even with the heaviest of tripods! And then the rain arrived. Slamming horizontally through the air making photography even more impossible! I sat this one out in the warmth of the ute cabin listening to the wind (and feeling it through the car itself) and rain when ping, ping on the windows. Whats that - HAIL! Amongst the lightning, wind and rain it had started hailing. Not overly thick and only wintry small hail but it gave a nice finish to the storm. Then just like that it was gone, leaving behind a rapid 8mm and a little bit of dam runoff. It continued over the hills and into the mallee weakening just a little where rainfalls were a bit lower. Reports of 8mm though from the Wynarka area suggest that isolated pockets held intensity over the ranges. However The mid north (Booborowie) only received 4.4mm. Certainly not what can be called widespread. By morning I had a total of 12mm in the gauge. The central Mt lofies did the best as they often do with lots of towns (Ashton, Lenswood, Bridgewater to name but a few) recording over th 20mm mark. Its the southeast for a change that faired best with Padthaway getting over 30mm! The lightning hit power supplies in the central hills knocking out the power to over 2000 homes!

It looked damned impressive on the radar as can be seen below. (doppler grab to the left)

17-06-08 East of the ranges squall

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In an unusual situation a significant squall line developed in NNW flow EAST of the Mt Lofty ranges. Isolated areas received torrential but short lived downpours in the early hours of the morning. The radar image dramatically shows the intensity. Meanwhile in the southern hills not a drop fell from the sky and strong winds blew all night drying out the already dry soil profile further. Rain deficets are worsening.

23-06-08 Behemoth High Dominates the Continent

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Just when we desperately needed winter to arrive a massive and powerful high pressure rising to a crzy 1041 hPa system moves in, stalls and dominates our weather for a week. Such stalling patterns have dominated for the last 12 months and caused rainfall and system failures time and time again. Just what will the year bring? A worrying waiting game indeed.

29-06-08 Wind, wind and a bit more wind

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A weak approaching front kicks up strong winds delivering 12 hours of strong gusty winds and then as icing on the cake 10 hours of gale force winds. As if this is not bad enough not a drop of precipitation accompanies the winds further drying soil and landscape in my area that at this time of year is adapted to wet, muddy conditions. But rain does fall, albeit small amounts, from a prefrontal NW infeed. In an impressive rain shadow in a type of lee wave over the ranges, a few mm falls over Adelaide plains and the western range front, then evaporates and reforms ~50 kms east of the ranges where (for example) Wynarka receives a life saving 4mm. A small animation of the rain shadow can be seen in the radar image to the right with an accompanying satellite image. The graph of wind from my WX is below.

Wind Update and a bit of rain 30th June

The 30th arrived and the wind was still blowing! 3 days of gales! An amazingly windy 3 days has buffeted my part of the hills. I am not alone in the pounding and by the evening of the 30th the nasty winds strengthened and spread across the state. Most notably the SE where the Bureau issued a storm force warning! It read as thus....

"Storm Force Wind Warning
For the South East Coast south of Beachport
W/SW winds increasing to 40/50 knots Monday evening, easing to 35/45 knots
before sunrise Tuesday, Seas 5 to 7 m. Swell 4 to 6 m."

For those that don't think in "knots", me included, this translates as 75 to near 100km/h winds! Gusts to 80km/h have already been recorded at Sellicks Hill and to 90km/h at Mt Lofty. The sheltered weather station had been recording gusts above 60km/h for almost 3 days! Out of the shelter of the trees gusts to a minimum of 80km/h buffeted my range. Rain was again patchy. Highest 24 hours to Monday morning (30th) was Forreston with 21mm. I recorded 14, Meadows 16, Kuitpo 11 and generally falls of similar amounts across the central Mt Lofties where the biggest falls were to be had. (I use the term "big" loosely) Another 5mm tops my location up to 19mm in total to monday evening. Some small hail was around the place during the mornings rain. Mostly over the northern hills and suburbs. Nothing to be seen over the southern hills hail wise. My June Total is 79mm. A bit over 50% of average. A site subsriber sent in this report from Forreston and the northern hills where falls were most intense. Chek out their rainfall accumulation graph tot he right!! "the down pour this morning in 15 minutes had us flooding…there was also severe localised hail each side of Gumeracha causing a car accident... "

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