Extratropical cyclones can also be dangerous when their low-pressure centers cause powerful winds and high seas.A subtropical cyclone is a weather system that has some characteristics of a tropical cyclone and some characteristics of an extratropical cyclone. They can form in a wide band of latitudes, from the equator to 50°. Although subtropical storms rarely have hurricane-force winds, they may become tropical in nature as their cores warm. See also
Tropical cyclones in 2022
2022 Atlantic hurricane season
2022 Pacific hurricane season
2022 Pacific typhoon season
2022 North Indian Ocean cyclone season
2022–23 South-West Indian Ocean cyclone season
2022–23 Australian region cyclone season
2022–23 South Pacific cyclone season

References
External links

United States National Hurricane Center – North Atlantic, Eastern Pacific
United States Central Pacific Hurricane Center – Central Pacific
Japan Meteorological Agency – Western Pacific
India Meteorological Department – Indian Ocean
Météo-France – La Reunion – South Indian Ocean from 30°E to 90°E
Indonesian Meteorological Department – South Indian Ocean from 90°E to 125°E, north of 10°S
Australian Bureau of Meteorology – South Indian Ocean and South Pacific Ocean from 90°E to 160°E
Papua New Guinea National Weather Service – South Pacific east of 160°E, north of 10°S
Fiji Meteorological Service – South Pacific west of 160°E, north of 25° S
MetService New Zealand – South Pacific west of 160°E, south of 25°S
Still, even an hCG over 2000 IU/L does not necessarily exclude the presence of a viable intrauterine pregnancy in such cases.As pregnancy tests, quantitative blood tests and the most sensitive urine tests usually detect hCG between 6 and 12 days after ovulation. It must be taken into account, however, that total hCG levels may vary in a very wide range within the first 4 weeks of gestation, leading to false results during this period. A rise of 35% over 48 hours is proposed as the minimal rise consistent with a viable intrauterine pregnancy.Gestational trophoblastic disease like hydatidiform moles ("molar pregnancy") or choriocarcinoma may produce high levels of βhCG (due to the presence of syncytiotrophoblasts - part of the villi that make up the placenta) despite the absence of an embryo. This, as well as several other conditions, can lead to elevated hCG readings in the absence of pregnancy. hCG levels are also a component of the triple test, a screening test for certain fetal chromosomal abnormalities/birth defects. A study of 32 normal pregnancies came to the result that a gestational sac of 1–3 mm was detected at a mean hCG level of 1150 IU/L (range 800–1500), a yolk sac was detected at a mean level of 6000 IU/L (range 4500–7500) and fetal heartbeat was visible at a mean hCG level of 10,000 IU/L (range 8650–12,200).