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Cyclone Marcia

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Severe Tropical Cyclone Marcia
Category 5 severe tropical cyclone (Aus scale)
Category 4 tropical cyclone (SSHWS)
Severe Tropical Cyclone Marcia at peak intensity on 19 February
Formed15 February 2015
Dissipated26 February 2015
Highest winds10-minute sustained: 205 km/h (125 mph)
1-minute sustained: 215 km/h (130 mph)
Lowest pressure930 hPa (mbar); 27.46 inHg
FatalitiesNone
Damage$52.9 million (2015 USD)
Areas affectedQueensland
Part of the 2014–15 Australian region cyclone season

Severe Tropical Cyclone Marcia was a Category 5 severe tropical cyclone that made landfall at its peak strength over central Queensland, near Shoalwater Bay on 20 February.[1] The cyclone went on to affect various areas including Yeppoon and Rockhampton. It reached Yeppoon as a Category 4 system, then traversed over the regional city of Rockhampton as a Category 3 system on the same day. Eventually, the cyclone weakened, moved southeast out to sea, then dissolved. Marcia caused at least A$67 million (US$52.9 million) worth of damage.[2]

Meteorological history

Map plotting the storm's track and intensity, according to the Saffir–Simpson scale
Map key
  Tropical depression (≤38 mph, ≤62 km/h)
  Tropical storm (39–73 mph, 63–118 km/h)
  Category 1 (74–95 mph, 119–153 km/h)
  Category 2 (96–110 mph, 154–177 km/h)
  Category 3 (111–129 mph, 178–208 km/h)
  Category 4 (130–156 mph, 209–251 km/h)
  Category 5 (≥157 mph, ≥252 km/h)
  Unknown
Storm type
triangle Extratropical cyclone, remnant low, tropical disturbance, or monsoon depression

The Australian Bureau of Meteorology (BoM) started to monitor a tropical low which developed within the monsoon trough to the southeast of Papua New Guinea on 15 February.[3][4] The system drifted generally eastwards and developed slowly under moderate vertical wind shear, until the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert early on 17 February when deep convection wrapping tightly into a well-defined centre.[5] Late on the same day, the BoM began to issue technical bulletins and designated the tropical low as 14U, although the bureau initially forecasted that it would only intensify into a category 1 cyclone prior to landfall.[6] The JTWC upgraded the partially-exposed system to a tropical cyclone and designated it as 13P early on 18 February, which also forecasted that it would intensify slightly.[7] At 09Z, the BoM reported that the tropical low intensified into a category 1 tropical cyclone and named it Marcia, as it had started to track southwestwards along the northwestern periphery of a low- to mid-layered subtropical ridge.[7][8]

When Marcia intensified into a category 2 tropical cyclone at 00:00 UTC on 19 February, it had developed a central dense overcast with a consolidating eyewall because of weakening vertical wind shear.[9][10] Thanks to very good poleward outflow into the westerlies, Marcia dramatically underwent rapid intensification and formed a clear eye, becoming a category 3 severe tropical cyclone at 05:00 and a category 4 system at 08:00 UTC.[11][12][13] Soon afterwards, it turned southwards along the western periphery of a subtropical ridge and reached peak intensity at 18:00 UTC as a category 5 severe tropical cyclone with 10-minute maximum sustained winds at 205 km/h (125 mph), featuring a very well-defined 35 km (20 miles) eye.[14][15] Maintaining strength, Marcia made landfall over the coast near Shoalwater Bay at 22:00 UTC (08:00 AEST on 20 February).[16]

Marcia making landfall over Queensland, Australia

At 12:00pm the system passed less than 16 km east of Yeppoon, where the local weather station recorded sustained 10-minute windspeeds of 120 km/h (65 kn), 3-second gusts of 156 km/h (84 kn) and a minimum pressure of 985hPa.[17][18] The system was downgraded to Category 3 at 2:00pm.

The cyclone passed over Rockhampton at approximately 2:30pm. Although still categorised as Category 3, the weather station recorded Category 1 windspeeds: 10-minute sustained winds of 82 km/h (44 kn), 3-second gusts up to 113 km/h (61 kn) and minimum pressure of 975hPa. Windspeed recorded a dual peak, indicating that the eye of the storm passed directly over the weather station on the western fringe of the city. Marcia was downgraded to Category 1 at 4:00pm.[17]

The system had a central pressure of 975 hPa, maximum 10-minute sustained winds of 65 knots (120 km/h) and gusts to 90 knots (170 km/h).[when?] The system was weakening slowly but beneath the standard rate owing to proximity to water on the eastern flank.[19] Marcia subsequently weakened further and weakened into a tropical low at 01:00 AEST on February 21 (15:00 UTC February 20), when the system was located about 100 km (60 mi)* to the west of Bundaberg.

Recorded windspeeds
Station location Time (AEST) 10-minute sustained winds
(km/h)
3-second gust
(km/h)
Pressure
(hPa)
Creal Reef 18:00, 19 February 146 189 977.8
Middle Percy Island 04:00, 20 February 156 208 970.2
Samuel Hill 98 170 977.3
Yeppoon 12:00, 20 February 120 156 985.4
Rockhampton 15:00, 20 February 82 113 985.5

Preparations

Satellite image of Lam (top-center) and Marcia (right) making near-simultaneous landfalls

Queensland

Prior to the category 5 storm making landfall the Premier of Queensland, Annastacia Palaszczuk, stated that South East Queensland should not expect a repeat of January 2011. Additionally, Flood rescue specialists and the Queensland State Emergency Service (SES) teams assisted with storm preparations and were placed on standby. Local Councils offered sandbags to residents who were likely to be affected by flooding. After landfall, the Queensland Disaster Recovery Committee convened.[20] More than 800 people bunkered down in the Yeppoon Cyclone Shelter, the most southerly located cyclone shelter in Queensland, located within the grounds of the Yeppoon State High School. Nearby towns and hamlets took their own precautions to protect themselves.[21][22]

Impact and aftermath

The Global Disaster Alert and Coordination System issued an advisory at 06:00 UTC on 20 February stating that up to 92,000 people had been affected by Category 1 windspeeds or higher, and that Marcia had peaked as a Category 3 storm.[23]

48,000 homes were left without power in Yeppoon, Rockhampton and Bundaberg as the storm moved south. Almost 3000 people requested assistance from the SES - including 800 in central Queensland. Significant structural damage occurred in the Yeppoon area and along the Capricorn Coast, with a number of houses having roofs blown off. Structural damage also occurred across Rockhampton and in the townships of Marmor and Mount Larcom.[24] Heavy rain fell across several regions and authorities evacuated residents from the small town of Jambin, south-west of Rockhampton, as localised flooding took place, which also affected Biloela.[25]

The observed windspeeds were lower than the predictions of the Bureau of Meteorology, which had been estimated using the Advanced Dvorak Technique. The Bureau was criticised for continuing to report the ADT estimates even after lower actual windspeeds had been recorded, notably by Jennifer Morahasy of Central Queensland University.[26] The International Wind Hazard Damage Assessment Group also expressed concern, saying "A community that receives an over-represented wind speed report may have potential for complacency in preparation or building standards in the future."[17] BOM rejected the criticism, stating that Percy Island was not located in the region of highest windspeed. Bureau chief Robb Webb also rejected claims BOM had relied solely on modelling, noting that the bureau worked with the US Joint Typhoon Warning Center to predict the storm's strength. The cyclone is still officially classified by the bureau as a Category 5.[27]

See also

References

  1. ^ Williams, Brian (19 February 2015). "Cyclone Marcia to bring high winds, flooding to southern Queensland". The Courier Mail. Retrieved 18 February 2015.
  2. ^ "Cyclone Marcia bill rises to $67m". Sky News. Retrieved 25 February 2015.
  3. ^ Queensland Regional Office (24 February 2015). Severe Tropical Cyclone Marcia (Report). Australian Bureau of Meteorology. Retrieved 24 February 2015.
  4. ^ "Tropical Cyclone Outlook for the Coral Sea on 16 February 2015". Australian Bureau of Meteorology. 16 February 2015. Archived from the original on 17 February 2015. Retrieved 19 February 2015.
  5. ^ "Tropical Cyclone Formation Alert". Joint Typhoon Warning Center. Archived from the original on 17 February 2015. Retrieved 3 March 2015.
  6. ^ "Tropical Cyclone Technical Bulletin at 1904 UTC 17/02/2015". Australian Bureau of Meteorology. Archived from the original on 18 February 2015. Retrieved 3 March 2015.
  7. ^ a b "Tropical Cyclone 13P (Thirteen) Warning Nr 001". Joint Typhoon Warning Center. Archived from the original on 18 February 2015. Retrieved 3 March 2015.
  8. ^ "Tropical Cyclone Advice Number 4". Australian Bureau of Meteorology. Archived from the original on 18 February 2015. Retrieved 3 March 2015.
  9. ^ "Tropical Cyclone Technical Bulletin at 0104 UTC 19/02/2015". Australian Bureau of Meteorology. Archived from the original on 19 February 2015. Retrieved 4 March 2015.
  10. ^ "Tropical Cyclone 13P (Marcia) Warning Nr 003". Joint Typhoon Warning Center. Archived from the original on 19 February 2015. Retrieved 4 March 2015.
  11. ^ "Tropical Cyclone Advice Number 11". Australian Bureau of Meteorology. Archived from the original on 19 February 2015. Retrieved 4 March 2015.
  12. ^ "Tropical Cyclone Advice Number 13". Australian Bureau of Meteorology. Archived from the original on 19 February 2015. Retrieved 4 March 2015.
  13. ^ "Tropical Cyclone 13P (Marcia) Warning Nr 004". Joint Typhoon Warning Center. Archived from the original on 19 February 2015. Retrieved 4 March 2015.
  14. ^ "Tropical Cyclone Technical Bulletin at 1812 UTC 19/02/2015". Australian Bureau of Meteorology. Archived from the original on 20 February 2015. Retrieved 4 March 2015.
  15. ^ "Tropical Cyclone 13P (Marcia) Warning Nr 005". Joint Typhoon Warning Center. Archived from the original on 20 February 2015. Retrieved 4 March 2015.
  16. ^ "Tropical Cyclone Technical Bulletin at 0005 UTC 20/02/2015". Australian Bureau of Meteorology. Archived from the original on 20 February 2015. Retrieved 4 March 2015.
  17. ^ a b c Daniel J Smith (20 Feb 2015), CTS Preliminary Damage Assessment Report - Tropical Cyclone Marcia, Queensland Australia (PDF), International Wind Hazard Damage Assessment Group, retrieved 24 Feb 2015
  18. ^ Sharnie Kim (23 Feb 2015). "Cyclone Marcia: James Cook University researchers assess Yeppoon, Rockhampton housing damage". ABC. Retrieved 24 Feb 2015.
  19. ^ "Tropical Cyclone Technical Bulletin - Tropical Cyclone Marcia". Bureau of Meteorology. Retrieved 20 February 2015. [dead link]
  20. ^ http://www.brisbanetimes.com.au/queensland/cleanup-begins-as-excyclone-marcia-weakens-and-heads-south-20150220-13kumf.html
  21. ^ http://www.couriermail.com.au/news/queensland/cyclone-marcia-central-queensland-residents-hunker-down-southeast-shores-up/story-fnkt21jb-1227226029591
  22. ^ Cyclone Shelters, Department of Housing & Public Works, Queensland Government (accessed 24 February 2015)
  23. ^ Green Tropical Cyclone alert for MARCIA-15 in Australia from 18/02/2015 12:00 UTC to 20/02/2015 06:00 UTC, Global Disaster Alert and Coordination System, 20 Feb 2015, retrieved 24 Feb 2015
  24. ^ http://www.news.com.au/national/cyclone-marcia-central-queensland-residents-hunker-down-southeast-shores-up/story-e6frfkp9-1227226029591
  25. ^ http://www.weatherzone.com.au/news/tropical-cyclone-marcia-downgraded-to-tropical-low-small-towns-facing-evacuations-as-more-rain-hammers-south-east-queensland/245538
  26. ^ Sam Phillips (24 February 2015), Climate researcher questions Cyclone Marcia’s category 5 status, Courier Mail, retrieved 24 February 2015
  27. ^ Nicholas McCallum (24 February 2015), Biologist questions Bureau of Meteorology's 'category 5' modelling on Cyclone Marcia, 9 News, retrieved 24 February 2015