Monthly Archives: April 2015

Rain event E NSW and possible east coast low 1 to 3 May 2015

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Rain event E NSW and possible east coast low 1 to 3 May 2015 2



Weather models appear to identify another east coast low forming from Friday 1 May and dissipating by Sunday 3 May 2015. Again, models vary as to its exact location however it appears at this stage that South East Queensland and North East New South Wales (coastal regions) will be most affected.

It seems that coastal showers will increase in frequency and intensity during Friday with a low forming during the early part of the weekend before weakening during Sunday.

Rainfall models suggest falls in excess of 200 mm and maybe 250 mm in some locations. Usually during these events, cloud and moisture coming off the coast is lifted by the coastal ranges of the Great Dividing Range with the heaviest falls occurring within the valleys. Places like the Bellinger Valley inland from Coffs Harbour often has heavy rain events due to orographic influences from such events. It is not uncommon to see small coastal rivers flood during these events.

Weather forecasts suggest some rain spreading south into the Hunter Valley and even Sydney from this event however falls are not expected to be as heavy as the previous system. In some areas, further rain may hamper clean up efforts from the last storm that has now cost some $200 million but some good news, the event is expected to be shorter lived and not as intense.

It is still a system that should be watched especially for the New South Wales North coast and South East Queensland should this event unfold.

Hailstorm: Spectacular 25 April 2015 hail storm and hail drifts

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Spectacular 25 April 2015 hail storm and hail drifts 4

Hailstorm hits Sydney with hail drifts





On Anzac Day afternoon 25 April 2015, I chased storms with Jimmy around Western Sydney. The event is well covered by Jimmy in his post so I will not repeat what has been stated. Generally we were working together to produce the best result for the day and we achieved far more than expected. Personally, I had not expected to see such a thunderstorm that produced prolific hail.

I had not undertaken any prior forecasting as I was busy working on other projects. However, when I received the phone call from Jimmy regarding the storms, I jumped at the offer and happy to be the driver.

I initially saw the cumulus towers to the west which looked interesting. After collecting Jimmy from his home, we went to local lookouts and watched the early cloud towers that initially struggled. Then it was off to nearby Rooty Hill and then Penrith Lakes where the action started.

The first storm with a very interesting base was visible to the west. I post one photo that shows a very interesting base but identify that it is no funnel cloud. It is just lowered cloud with hills in the way but it shows the structure of the cloud base.

When this was close enough, it was a case of driving south through Penrith then east along the M4 Motorway. We were initially going to intercept this storm but a new growing and broadening cloud base was of more interest so we decided not to go south but wait. That proved to be a very good move.

The storm passed over us where we were being within the Wonderland Industrial Park. There were three bursts of hail from it and heavy rain. We then shifted north then east onto the Great Western Highway where the best hailstorm I have seen for a long time occurred. There were hail drifts and I could not see the road surface. There were plenty of photo opportunities and at one stage became stuck in hail but managed to get clear and continue.

Some of my favourite photos include having the car bonnet carpeted with hail and holding a large conglomerate of hail in my hand where hail had fused together.

We finished up getting another hailstorm over Blacktown and a further event around Prospect before returning to Pemulway and later the M4 Motorway Caltex Twin Service Stations to measure hail size.

The chase ended towards evening and it certainly made a fitting end to the storm season.

Hail Drifts Western Sydney 25th April 2015

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Hail Drifts Western Sydney 25th April 2015 20

0425jd089What an incredible afternoon with hailstorms through Sydney. The Great Western Highway was near impassible with hail drifts covering the road. Hail size was up to 2 to 3cm measured mostly 1.5 to 2cm diameter. We began our day at Quakers Hill and then moved to Rooty Hill. The day started relatively slow with cumulus struggling over the mountains occasionally taking off then glaciating and collapsing. It was the storms that developed near Lithgow that eventually consolidated and took over.

The storms became anchored in the low level flow and gradually moved slightly to the left of the mean level flow. Harley and I then decided to move from Rooty Hill to Penrith - deciding the most ideal vantage point proved tricky given the deviant flow. The Penrith Lakes region was almost ideal and allowed full view of the storm structure with precipitation but perhaps a touch ambient light creeping through making contrast a little tricky. A nice wall cloud developed under the well structured tiered structure! Occasional lightning was observed. 0425jd030 0425jd045 0425jd046 0425jd055 Rain began to drop and the storm making its move, it was time to move! A touch slow through Penrith but no need to panic. 0425jd071 0425jd074 0425jd079We headed for an eastern vantage point only to head all the way to Eastern Creek. Another extensive base had developed east of Penrith and and both Harley and took note of this and remained stationary. The storm literally exploded overhead and we eventually made our way to the Great Western Highway. After a brief phone call from my cousin Stephen about a hailstorm he had just witnessed and wow! Hail drifts! Just like that right near the highway and within about 100-200 metres from no cover!  0425jd0800425jd093 0425jd088 0425jd089Turning onto the Great Western Highway was fun and the adventure was about to begin - very rarely do you have 3 lanes virtually to yourself. Cars as per usual parked under bridges but we kept heading east. The depth of the drifts became sufficient almost to stop the vehicle from moving - probably up to 10 to 15cm deep in places. Hail piled up on the car windscreen as well like snow! It was simply crazy. Hail sized were estimated to be between 1.5 to 3cm - measured later as maximum 2.5cm hailstones. Gradually the hail drifts thinned somewhat and we made our way further east with a substantial base evident. At Toongabbie, we stopped for a brief shot of hail on the windscreen. Indecisions - should we head back to photograph the hail drifts? This changed to an intercept of the next cell coming towards Blacktown. More hail! Believe or not, we ended up through to Seven Hills through more hail once more and  then watching a beautiful base and updraft flanking line! 0425jd112 0425jd115 0425jd116 0425jd105Decision again to head for the hail drafts took us through another hailstorm and more hail covering the lawns. Back onto the highway west bound and closing in on the hail swathe - traffic jams. We had no way of not only getting to observe the hail drifts but to get a good vantage point to observe the impressive mammatus now appearing! Wow! 0425jd134 0425jd137 0425jd127This was some of the best mammatus  had observed in Sydney personally! 0425jd155 0425jd146 0425jd148The rest of the evening we attempted to photograph and measure hailstones. Largest hailstones were in the main hail drifts near Eastern Creek bordering Rooty Hill. Hail still lay on the ground in patches. 0425jd166 0425jd168 0425jd173 0425jd159 image image image image image image image image image