Australian Government Bureau of Meteorology
New South Wales
TOP PRIORITY FOR IMMEDIATE BROADCAST
Detailed Severe Thunderstorm Warning
for Intense Rainfall
for parts of Gosford/Wyong, Sydney and Blue Mountains/Hawkesbury areas.
Issued at 6:06 pm Saturday, 17 January 2026.
INTENSE RAINFALL WITH THUNDERSTORMS SOUTHERN CENTRAL COAST.
INTENSE RAINFALL for the following areas:
Blue Mountains/Hawkesbury, Gosford/Wyong and Sydney
The Bureau of Meteorology warns that, at 6:00 pm, a VERY DANGEROUS THUNDERSTORM likely to produce heavy, locally intense rainfall that may lead to dangerous and life-threatening flash flooding was detected near Calga and Woy Woy. This thunderstorm is slow moving. It is forecast to affect Upper Mangrove by 7:00 pm.
Other severe thunderstorms likely to produce heavy rainfall that may lead to flash flooding were detected near Bundeena and Kurnell. These thunderstorms are slow moving. They are forecast to affect Hurstville, Botany and waters off the Royal National Park by 6:30 pm and Sutherland, Sydney Airport and Canterbury by 7:00 pm.
133 MM OF RAINFALL WAS RECORDED AT PEARL BEACH IN THE 2 HOURS TO 3:43 PM.
93.5 MM OF RAINFALL WAS RECORDED AT ETTALONG IN THE 1 HOUR TO 2:22 PM.
67 mm was recorded at Cronulla South in the 2 hour to 5:35 pm.
58 mm of rainfall was recorded at East Gosford in the 1 hour to 2:55 pm.
56.6 mm of rainfall was recorded at Gosford in the 1 hour to 2:53 pm.
66 mm of rainfall was recorded at Bensville in the 1 hour to 2:49 pm.
57 mm of rainfall was recorded at Kilcare Heights in the 1 hour to 2:39 pm.
65 mm of rainfall was recorded at Woy Woy in the 1 hour to 2:33 pm.
48.5 mm of rainfall was recorded at Kincumber Mountain in the 30 minutes to 2:30 pm.
71 mm of rainfall was recorded at Koolewong in the 1 hour to 2:26 pm.
62.5 mm of rainfall was recorded at Avalon in the 1 hour to 2:13 pm.
The State Emergency Service advises that people should:
* Keep clear of creeks and storm drains.
* Don't walk, ride your bike or drive through flood water.
* If you are trapped by flash flooding, seek refuge in the highest available place and ring 000 if you need rescue.
* Stay indoors away from windows, and keep children and pets indoors as well.
For emergency help in flood and storms, ring the SES on 132 500.
Stay updated on the Hazards Near Me NSW app or the ACT ESA website (https://esa.act.gov.au).
A more general severe thunderstorm warning is also current for parts of the Hunter, Metropolitan and Illawarra districts.
Other warnings may be current.
The next warning is due to be issued by 7:10 pm.
Check https://www.bom.gov.au/weather-and-climate/warnings-and-alerts. Warnings are also available through TV and Radio broadcasts or call 1300 659 210. The Bureau and State Emergency Service would appreciate warnings being broadcast regularly.
Forecast
Williamtown (32.8068°S, 151.8442°E, 18m AMSL) set as my default location ›
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7 day forecast
Today: Cloudy. High chance of showers, most likely in the morning and afternoon. The chance of a thunderstorm in the morning and early afternoon, possibly severe with heavy rain which may lead to flash flooding near the coast. Winds SE 25 to 35 km/h. Overnight temperatures falling to between 15 and 18 with daytime temperatures reaching between 18 and 24.
Forecast for Williamtown (32.8068°S, 151.8442°E, 18m AMSL) Sun Mon Tue Wed Thu Fri Sat Summary
Minimum 19° 19° 18° 17° 16° 18° 19° Maximum 23° 24° 24° 24° 26° 27° 28° Chance of rain 80% 50% 50% 30% 30% 10% 30% Likely amount 10-20mm 1-5mm 1-5mm 1-5mm < 1mm < 1mm < 1mm UV index Extreme Extreme Extreme Extreme Extreme Extreme Extreme Fire Danger Rating Moderate Moderate Moderate Moderate - - - Frost risk Nil Nil Nil Nil Nil Nil Nil 9am 3pm 9am 3pm 9am 3pm 9am 3pm 9am 3pm 9am 3pm 9am 3pm Wind speed 20
(km/h)26
(km/h)18
(km/h)23
(km/h)15
(km/h)25
(km/h)17
(km/h)25
(km/h)11
(km/h)20
(km/h)9
(km/h)21
(km/h)10
(km/h)23
(km/h)Wind direction SE SE SSE SSE SSE SSE SW SSW WSW SSE SSE ESE E E Relative humidity 88% 83% 73% 65% 71% 59% 68% 56% 68% 54% 69% 57% 71% 57% Dew point 19°C 19°C 18°C 16°C 17°C 15°C 15°C 14°C 16°C 15°C 18°C 17°C 19°C 18°C -
Sunrise and sunset times
Sunrise / Sunset for Williamtown (32.8068°S, 151.8442°E, 18m AMSL) First light Sunrise Sunset Last light Moon rise Moon set Moon phase New moon First quarter Full moon Last quarter 5:35am EDT 6:02am EDT 8:03pm EDT 8:31pm EDT 4:58am EDT 7:54pm EDT
Waning crescent
New moon Jan 19 First quarter Jan 26 Full moon Feb 02 Last quarter Feb 09 -
Warnings
- Detailed Severe Thunderstorm Warning (Intense Rainfall) for parts of Gosford/Wyong, Sydney and Blue Mountains/Hawkesbury areas
- Detailed Severe Thunderstorm Warning (Intense Rainfall) for parts of Gosford/Wyong, Sydney and Blue Mountains/Hawkesbury areas
- Severe Thunderstorm Warning (Heavy, Locally Intense Rainfall) for parts of Hunter, Metropolitan and Illawarra
- Severe Thunderstorm Warning (Heavy, Locally Intense Rainfall) for parts of Hunter, Metropolitan and Illawarra
- Hazardous Surf Warning for Hunter and Sydney coasts. Cancellation for Illawarra, Batemans and Eden coasts
- Strong Wind Warning for Sydney Enclosed Waters & Hunter, Sydney, Illawarra and Batemans coasts
- cancellation of coastal hazard Warning for Sydney Metropolitan, Hunter, Illawarra & Mid North and South coasts
- cancellation of coastal hazard Warning for Sydney Metropolitan, Hunter, Illawarra & Mid North and South coasts
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Temperature for next 7 days
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Rain for next 7 days