Topic: Hailstorms Sydney Central Coast 15 August 2010

[Jimmy Deguara]

Hi,

When I went outside this morning - two things caught my attention: the clearing cloud band to the east and grwoing cumulus to the west. THis was your classic trough line scenario. Despite this, I was surprised when Kimberly suggested it was raining. I went outside and drops were large and then something bounced! Hail - tiny hail but deinitely hailstones. It was coming from a cumulus that had basically glaciated and then rapidly collapsing.

However, then there was a cumulus that developed within this region of collapse and this grew to a cell that changed direction further east near Dee Why! Meanwhile, another line of activity had rapidly approached with hail as well pelting down. Very interesting situation. The main activity has shifted further north now.

Not a bad start to the season. This does remind of the odd early hailstorm that can occur during the August with some wind squalls. We had the two occurences of hail.

Regards,

Jimmy Deguara

[Dave Nelson]

hey Jimmy and Co,

  yeah I could see the the cells building over the moountains as Cindy and I arrived at church in Norwest Blv ~ 10:30 am  commented to her that it was a similar setup to a few weeks ago that produced NE moving storms from Camden to Penrith. 
Around 12 noon we could hear a growing roar of rain/hail on the roof of the auditorium,
has to be pretty intense for that to happen.   Heard several rumbles of thunder and saw a couple of flashes out to the east as we got out of the building ~ 1235hrs
 By then the storm has well and truely passed over and was over the nthrn suburbs.
Radar indicates that this storm intensified over the Nth Sydney, Terry Hills region.

As I write this, 1345hrs  another cell is passing over sthrn Sydney from west to east.

cheers
Dave

[Harley Pearman]

The first thunderstorm for at least 101 days over Blacktown. The change of season to spring is now close.

I was at the same place as Dave during the event at Bella Vista. My friend Karina reported to me small pea size hail at Blacktown and some wind.

Looking at The GPATS Lightning Tracker, some 47 lightning flashes across Sydney with a peak between 12 noon and 1 pm. Of these the tracker shows 5 flashes around Baulkham Hills, 5 more around Fairfield, 13 around Dee Why plus another 11 off the coast of Dee Why or Sydney's Northern Beaches. The others were highly scattered. Generally the storm peaks were around Western Sydney (Such as Fairfield), Baulkham Hills, northern areas of Sydney such as Terrey Hills and Dee Why.

The highest rainfalls are Ingleburn 6 mm (Although isolated), 3 mm at Kings Langley and Chatswood, 4 mm at Baulkham Hills and West Pennant Hills and 2.5 mm at Baulkham Hills Swimming Pool (BOM Weather Stations for 15/8/2010).

Harley Pearman

[Michael Bath]

Got a phone call "from a concerned EWN member" about the hail around noon. Was surprised to see such interesting development, though not so much after looking at the soundings for Sydney and Wagga. Both support low-topped storms. The mid level trough appears to have been a little stronger than forecast, with -22 over Sydney this morning and -25 on approach from the southwest. Moisture picked up a bit too during the passage of the change.

128km Radar Loop for Sydney (Terrey Hills), 23:00 14/08/2010 to 05:00 15/08/2010 UTC

[Richary]

From Rydalmere (just east of Parramatta) I noticed the first lot of cloud coming over, that looked like it could have been blowing off the top of a cumulus cloud, typical look of summer thunderstorms. It then started raining lightly, then heavily, and then we had some pea sized hail. Only lasted about 5 minutes. Was quite surprised as it didn't appear that intense on the radar images.

About 20 minutes later heard thunder and it was very black to my west, so decided to put the cars away. No hail with the 2nd line here though, though it was quite windy as the rain band pushed through. Grand total of rain about 1.7mm looking at the guage. Both events were very fast moving as they appeared on the radar, and the first one that produced the hail looked like it had weakened somewhat as it got to me, so may have been more intense a bit further west. The second band produced a number of CGs quite nearby but fairly random.

TV news tonight showed some hail in places, enough to build a mini snowman at Dee Why - what fell here had melted by the time the rain finished. The temperature drop as the second band came through was quite noticeable as well.