Tag Archives: Tropical Storm Katia

Idalia Brings Gusty Winds to Bermuda.

The circulation around former Tropical Storm Idalia brought gusty winds to Bermuda on Saturday. At 11:00 a.m. EDT on Saturday the center of former Tropical Storm Idalia was located at latitude 31.6°N and longitude 63.5°W which put it about 90 miles (145 km) east-southeast of Bermuda. Idalia was moving toward the east at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h). The minimum surface pressure was 999 mb.

A Tropical Storm Warning was in effect for Bermuda.

The circulation around former Tropical Storm Idalia existed primarily in the lower levels of the atmosphere on Saturday. Bands of showers and lower clouds were revolving around the center of former Tropical Storm Idalia. Thunderstorms were occurring along a warm front northeast of the center of Idalia’s circulation. An upper level trough off the East Coast of the U.S. was producing strong westerly winds that were blowing over the top of Idalia’s circulation. Those winds were causing strong vertical wind shear. The circulation around former Tropical Storm Idalia was large. Winds to tropical storm force extended out 205 miles (335 km) from the center of Idalia’s circulation.

The large circulation around former Tropical Storm Idalia was producing gusty winds in Bermuda. A weather station at the L. F. Wade International Airport (TXKF) reported a sustained wind speed of 37 m.p.h. (59 km/h) and a wind gust of 56 m.p.h. (91 km/h). A weather station at St. George’s Pier reported a sustained wind speed of 46 m.p.h. (74 km/h) and a wind gust of 56 m.p.h. (91 km/h). A weather station at an elevated location at the National Museum of Bermuda reported a sustained wind speed of 64 m.p.h. (104 km/h) and a wind gust of 79 m.p.h. (128 km/h). Heavy rain was falling northeast of Bermuda along a warm front.

The upper level trough off the East Coast of the U.S. will steer former Tropical Storm Idalia toward the northeast during the next 36 hours. On its anticipated track, the center of Idalia will move away from Bermuda during the next 36 hours. The winds speeds will decrease in Bermuda when former tropical storm Idalia moves farther away.

Elsewhere over the Atlantic Ocean, Tropical Storm Gert strengthened east-southeast of Bermuda and former Tropical Depression Twelve strengthened to Tropical Storm Katia northwest of the Cabo Verde Islands. At 11:00 a.m. EDT on Saturday the center of Tropical Storm Gert was located at latitude 27.8°N and longitude 54.1°W which put it about 710 miles (1145 km) east-southeast of Bermuda. Gert was moving toward the north-northeast at 3 m.p.h. (5 km/h). The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h). The minimum surface pressure was 999 mb.

At 11:00 a.m. EDT on Saturday the center of Tropical Storm Katia was located at latitude 23.9°N and longitude 29.7°W which put it about 660 miles (1060 km) north-northwest of the Cabo Verde Islands. Katia was moving toward the north-northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h). The minimum surface pressure was 1000 mb.

Cat. 5 Hurricane Irma Moving Over Northern Leeward Islands

Category 5 Hurricane Irma moved over the northern Leeward Islands on Wednesday morning.  At 5:00 a.m. EDT on Wednesday the center of Hurricane Irma was located at latitude 17.9°N and longitude 62.6°W which put it about 35 miles (55 km) east-southeast of St. Martin.  Irma was moving toward the west-northwest at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 185 m.p.h. (295 km/h) and there were wind gusts to 210 m.p.h. (340 km/h).  The minimum surface pressure was 912 mb.

The core of Hurricane Irma moved across Antigua, Barbuda, St. Barthelemy and St. Martin in recent hours.  It will reach Anguilla later this morning.

Hurricane Watches were in effect for Antigua, Anguilla, Barbuda, Montserrat, St. Kitts, Nevis, Saba, St. Eustatius, Sint Maarten, St. Martin, St. Barthelemy, the British Virgin Islands, the U.S. Virgin Islands, Puerto Rico, Vieques, Culebra, Guadeloupe, the southeastern Bahamas including the Acklins, Cooked Islands, Long Cay, the Iguanas, Mayaguane, the Ragged Islands, the Turks and Caicos, and the portion of the coast of Cabo Engano, Dominican Republic to the northern border with Haiti.  Hurricane Watches are in effect for the central Bahamas, the portion of the coast from Le Mole St. Nicholas to the northern border with Haiti and from Matanzas province to Guantanamo province in Cuba.  A Tropical Storm Warning is in effect for the portion of the coast from Cabo Engano, Dominican Republic to the southern border with Haiti.  A Tropical Storm Watch is in effect for the portion of the coast from Le Mole St. Nicolas, Haiti to Port Au Prince.

Hurricane Irma maintained its intensity during the northern overnight hours.  It has a circular eye with a diameter of 30 miles (48 km).  The eye is surrounded by a ring of strong thunderstorms and the strongest winds are occurring in that ring of storms.  Winds to hurricane force extend out about 60 miles (95 km) from the center.  Winds to tropical storm force extend out about 160 miles (260 km) from the center.

The Hurricane Intensity Index (HII) is 44.1.  The Hurricane Size Index (HSI) is 19.8 and the Hurricane Wind Intensity Size Index (HWISI) is 63.9.  Those indices indicate that Hurricane Irma is capable of causing widespread catastrophic wind damage.

Hurricane Irma will continue to move over an environment very favorable for hurricanes.  Irma will stay over water where the Sea Surface Temperature is near 30°C.  The upper level winds will remain weak for several more days and there will be little wind shear.  An upper level trough over the eastern U.S. will produce strong winds when Irma gets closer to Florida.  The wind shear will increase at that time.  Hurricane Irma could go through eyewall replacement cycles which would cause fluctuations in intensity.

Hurricane Irma is moving near the western end of a subtropical high pressure system over the Atlantic Ocean which is steering Irma toward the west-northwest.  The west-northwesterly motion is expected to continue for several more days.  Eventually, the upper level trough over the eastern U.S. is forecast to turn Hurricane Irma toward the north when it approaches Florida.  On its anticipated track the center of Hurricane Irma is forecast to pass north of Puerto Rico and Hispaniola.

Elsewhere, Tropical Storm Jose is trailing behind Hurricane Irma and Tropical Storm Katia has developed over the southern Gulf of Mexico.  At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Jose was located at latitude 12.5°N and longitude 42.8°W which put it about 1255 miles east of the Leeward Islands.  Jose was moving toward the west at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 1002 mb.

At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Katia was located at latitude 22.1°N and longitude 96.3°W which put it about 105 miles (165 km) east of Tampico, Mexico.  Katia was moving toward the east at 2 m.p.h. (3 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1006 mb.