Cyclone Gonu

Toward the end of May 2007, the monsoon trough spawned a low-pressure area in the eastern Arabian Sea. A favorable upper-level environment allowed convection to improve, and by late on June 1, the system developed to the extent that the India Meteorological Department (IMD) classified it as a depression. It tracked westward along the southwestern periphery of a mid-level ridge over southern India. Convection continued to organize, and early on June 2, the Joint Typhoon Warning Center (JTWC) classified the storm as Tropical Cyclone 02A, about 685 km (425 mi) southwest of Mumbai. Upon first forming, the system contended with the entrainment of dry air to the northwest of the storm, which was expected to limit intensification. Later in the day the IMD classified the system as Cyclonic Storm Gonu about 760 km (470 mi) southwest of Mumbai, India. As a mid-latitude trough developed over Pakistan, Gonu turned to the north and northeast, though it resumed a westward track after ridging built to the north of the storm. With a solid area of intense convection, it rapidly intensified to attain severe cyclonic status early on June 3, and with good outflow the JTWC upgraded it to the equivalent of a minimal hurricane. The dry air ultimately had a smaller impact on the intensification than previously estimated. A well-defined eye developed in the center of convection, and after moving over a local increase in ocean heat content, Gonu rapidly deepened. Late on June 3, the IMD upgraded the storm to Very Severe Cyclonic Storm Gonu. With warm waters, and gusts to , about 285 km (175 mi) east-southeast of Masirah Island on the coast of Oman. The IMD upgraded it to Super Cyclonic Storm Gonu late on June 4, with peak 3-min sustained winds reaching and an estimated pressure of 920 mbar. This made it the first super cyclonic storm in the Arabian Sea on record. Due to land interaction with Oman, the inner core of deep convection rapidly weakened, and over a period of 24 hours the intensity decreased by . According to the IMD, Cyclone Gonu crossed the easternmost tip of Oman near Muscat early on June 6, with winds of 143 km/h (89 mph). After emerging into the Gulf of Oman, the cyclone briefly re-intensified slightly, possibly due to the warm waters. On June 6, the cyclone turned to the north-northwest, and later that day the JTWC downgraded Gonu to tropical storm status. The IMD followed suit by downgrading Gonu to severe cyclonic storm status, and later to cyclonic storm status early on June 7. Gonu crossed the Makran coast in Iran six hours later, and the IMD stopped issuing advisories on the cyclone. This made it the first tropical cyclone on record to hit the country since 1898. After landfall, Gonu persisted as a remnant low over Iran through June 8. ==Preparations==

The Oman Chairman of the National Committee for Civil Defence, General Malek Bin Sulaiman Al Ma'amari, remarked the nation had already developed a contingency plan, which included the activation of army and police personnel after the storm's passage. Significant damage was expected, especially in northeastern areas, along with up to 150 mm (6 in) of rainfall and very strong winds. Officials recommended citizens evacuate from potentially affected areas, Overall, more than 20,000 people evacuated to emergency shelters. A state of emergency was declared for the nation. The Mina al Fahal oil terminal closed for over three days due to the threat of the storm. Omani officials closed government offices for two days and declared a five-day-long national holiday. Most businesses near the coastline were closed prior to the announcement. The nation's Civil Aviation Authority, along with Muscat International Airport (then named as "Seeb International Airport") and Salalah International Airport canceled all flights at 20:00 UTC on June 5. In Saudi Arabia and the United Arab Emirates, both members of OPEC, no official warnings had been issued due to Gonu. The storm was not expected to disrupt oil supplies from these two nations. However, oil prices rose early on June 5 because of concerns of disruptions caused by Gonu, as well as the threat of nationwide strikes in Nigeria, Africa's biggest oil producer. Crude oil for July delivery rose $1.13, or 1.7 percent, to $66.21 Monday on the New York Mercantile Exchange, the highest close in 15 days. Futures reached $66.48, the highest intraday price since April 30. The contract was at $65.95 a barrel, down 26 cents, in after-hours electronic trading at Tuesday in Singapore. Tom Kloza, chief oil analyst at the Oil Price Information Service, said he doubted the increase could be attributed to Gonu. "I don't know if you can really attribute any of the gain to the cyclone", he said. "It's an excuse, as opposed to a reason, for the rise in prices." In Pakistan, officials recommended fishermen remain within 50 km (30 mi) of the coastline, due to anticipated rough waves in the open ocean. Naval authorities in the United States warned ships to avoid the cyclone in the Arabian Sea. The Iran Department of Meteorology declared storm warnings for the country's southeastern coastline; the agency anticipated moderate to severe precipitation and gusty winds. All flights in and out of the Konarak Airport were canceled during a 48-hour period. Additionally, all hospitals in Sistan and Baluchestan Province were put on red alert. The Iran chapter of the Red Cross advanced the delivery of necessary relief supplies. ==Impact==

Across its path, Cyclone Gonu caused heavy damage and many fatalities. Gonu produced strong waves along much of the coastline, leaving many coastal roads flooded. There was a 5.1 meter (17 foot) storm surge and a 200 m (660 ft) incursion of seawater inland at Ras al-Hadd; other areas along the coast had similar levels. Oman Strong winds knocked out power and telephone lines across the eastern region of the country, leaving thousands isolated until the lines were repaired hours later. The cyclone caused extensive damage along the coastline, including in the city of Sur and the village of Ras al Hadd at the easternmost point of the Omani mainland. In Muscat, winds reached , leaving the capital city without power. Strong waves and heavy rainfall flooded streets and some buildings. Police workers in the city sent text messages to keep people away from flooded streets to prevent electrocutions. Little damage was reported to the oil fields of the nation. Overall, the cyclone killed 50 people in the country; by the fourth day after it struck the country, 27 people had been reported missing. and damage in the country was estimated at $4.2 billion (2007 USD). The waves along the coastline were reported to be 10 m (32 ft) high, which destroyed about a dozen fishing boats. About 300 boats were moved from the water or emptied of equipment, and overall damage to the port of Fujairah was reported as severe. A boat sank by the port, leaving its ten passengers missing. Iran Upon striking Iran, Gonu dropped moderate to heavy rainfall, including 74 mm (2.91 in) in the city of Chabahar. with many homes near the coastline receiving damage. Flooding from the rainfall also destroyed a dam in Nikshahr County. The cyclone was reported to have sunk a number of boats off the eastern coast of Gwadar. It was feared that fishing launches that had ventured into the open sea may have been stranded. At least three houses and one school were destroyed and 210 anchored fishing boats were badly damaged anchored in the coastal town of Sar Bandar in Baluchistan province ==Aftermath==

Flights to and from Muscat resumed after three days while Fujairah reopened on June 7 after it was closed the day before. Across the northern Arabian Sea, the passage of Gonu produced stronger winds and significant upwelling – an oceanographic phenomenon that involves the replacement of the nutrient-depleted surface water with deeper nutrient-rich water; the passage caused a significant increase in phytoplankton. Additionally, the cyclone delayed the arrival of the Indian Ocean south-west monsoon in the Western Ghats in India. In Oman, production of desalinated water was interrupted, as both of Oman's desalination plants failed. The first, Ghubrah, lost supplies of natural gas, halting production; while the second, Barka, sustained a damaged switchgear due to flooding. These plants provided water to Muscat's 631,000 residents and surrounding areas, triggering severe water shortages across eastern Oman. To rectify the situation, officials used water tanks. The water returned to near normal in five days, as the two plants returned to service. Additionally, electricians worked quickly to repair the power outages across the region. Five days after Gonu hit, utilities were restored to most of Muscat and the coastal provinces. The Omani army assisted residents in returning to their houses. Even though the Omani government did not request any international aid, the United States offered assistance through naval ships in the area; this was eventually rejected. In the months after the storm, the government allocated funds for the removal of debris and trees, as well as restoration of roads in tourist areas. Additionally, the National Committee for Civil Defence set up 139 buildings to provide temporary housing for 8,192 people. Services such as water and electricity were gradually restored, and people returned to their homes. By two weeks after the storm's passage, most of those remaining in shelters were from Qurayat, one of the most severely affected villages. After the passage of the cyclone, the Iran chapter of the Red Cross and its volunteers worked in conjunction with the military to distribute relief supplies to villages using trucks and helicopters. The branch in Sistan and Baluchestan Province distributed over 10,000 blankets, 1,300 tents, 400 clothing items, 82,000 loaves of bread, and 87,000 bottles of water to affected citizens. In total, 61,558 families received aid from the Red Cross in Iran. The Iranian government provided monetary relief to the affected people. Officials worked to restore roads, bridges, and power systems in the affected areas, although repairs were more difficult in some locations; by a week after the storm, several villages remained surrounded by floodwaters. ==Records==

Cyclone Gonu set several intensity records. When it became a very severe cyclonic storm on June 3, Gonu became the strongest tropical cyclone on record in the Arabian Sea. It was the only super cyclonic storm, which is a tropical cyclone with 3-minute sustained winds of at least , in the region, until Cyclone Kyarr 12 years later. ==See also==