Tag Archives: Tropical Storm Don

Tropical Storm Don Spins South-southeast of Newfoundland

Tropical Storm Don was spinning over the Atlantic Ocean south-southeast of Newfoundland on Friday morning. At 11:00 a.m. EDT on Friday the center of Tropical Storm Don was located at latitude 35.8°N and longitude 46.5°W which put it about 825 miles (1330 km) south-southeast of Cape Race, Newfoundland. Don was moving toward the west-northwest at 10 m.p.h. (16 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 1002 mb.

The circulation around Tropical Storm Don was well organized on Friday morning. The inner end of a rainband wrapped around the center of Don’s circulation. A clear area was visible on satellite images at the center of Tropical Storm Don. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. The circulation around Tropical Storm Don was small. Winds to tropical storm force extended out 60 miles (95 km) from the center of circulation.

Tropical Storm Don will move through an environment that will be marginally favorable for intensification during the next 24 hours. Don will move over water where the Sea Surface Temperatures are near 25˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Don could intensify during the next 24 hours. Don will move over the warmer water of the Gulf Stream for a brief time on Saturday. Tropical Storm Don could strengthen while it is over the Gulf Stream, but Don will then move over much colder water when it gets north of the Gulf Stream.

Tropical Storm Don will move around the western part of a high pressure system over the northeastern Atlantic Ocean. The high pressure system will steer Don toward the northwest during the next 24 hours. On its anticipated track, Tropical Storm Don will continue to make a big clockwise loop over the Central Atlantic south of Newfoundland.

Tropical Storm Don Strengthens over the Central Atlantic

Tropical Storm Don strengthened over the Central Atlantic Ocean on Wednesday night. At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Don was located at latitude 33.9°N and longitude 40.9°W which put it about 825 miles (1330 km) west-southwest of the Azores. Don was moving toward the west at 6 m.p.h. (10 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 1002 mb.

Tropical Storm Don strengthened on Wednesday night as it continued to make a big clockwise loop over the Central Atlantic Ocean west of the Azores. Don looked more like a tropical storm on satellite images. The shape of the cloud pattern was more circular. Thunderstorms formed along the inner end of a band just to the east of the center of Don’s circulation. Other bands of showers and thunderstorms were revolving around the center of Tropical Storm Don. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 70 miles (110 km) from the center of Don’s circulation.

Tropical Storm Don will move through an environment favorable for intensification during the next 24 hours. Don will move over water where the Sea Surface Temperatures are near 25˚C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Tropical Storm Don will intensify during the next 24 hours.

Tropical Storm Don will move around the southwestern part of a high pressure system over the northeastern Atlantic Ocean during the next 24 hours. The high pressure system will steer Don slowly toward the west. On its anticipated track, Tropical Storm Don will continue to make a big clockwise loop over the Central Atlantic west of the Azores.

Tropical Storm Don Starts Big Loop West of the Azores

Tropical Storm Don started to make a big, clockwise loop over the Atlantic Ocean west of the Azores on Monday. At 11:00 p.m. EDT on Monday the center of Tropical Storm Don was located at latitude 37.4°N and longitude 40.4°W which put it about 735 miles (1180 km) west of the Azores. Don was moving toward the southeast at 13 m.p.h. (20 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 1007 mb.

Former Subtropical Storm Don went through several stages as it made a transition to a tropical storm. Don weakened to a subtropical depression on Sunday while it was over cooler water and in a region with more vertical wind shear. It made a transition from a subtropical depression to a tropical depression on Monday morning, when more thunderstorms developed in the northeastern part of the circulation. Don then strengthened to a tropical storm on Monday evening.

Tropical Storm Don was over water where the Sea Surface Temperatures were near 24˚C on Monday evening. The distribution of thunderstorms in Tropical Storm Don remained asymmetrical. Most of thunderstorms were occurring in bands in the northeastern part of Don’s circulation. The strongest winds were also occurring in that part of Tropical Storm Don. Winds to tropical storm force extended out 105 miles (165 km) in the northeastern part of Don. Bands in the other parts of Tropical Storm Don consisted primarily of showers and lower clouds. The winds in the other parts of Don’s circulation were blowing at less that tropical storm force.

Tropical Storm Don will move through an environment that will be only marginally favorable for intensification during the next 36 hours. Don will move over water where the Sea Surface Temperatures are near 25˚C. It will move under the eastern side of an upper level low over the Central Atlantic Ocean. The upper level low will produce southwesterly winds that will blow toward the top of Don’s circulation. Those winds will cause moderate vertical wind shear. The wind shear will inhibit intensification. Tropical Storm Don could strengthen a little during the next 36 hours, but its intensity may not change much.

Tropical Storm Don will move around the northern part of a high pressure system over the Central Atlantic Ocean during the next 36 hours. The high pressure system will steer Don toward the south during the next 36 hours. Don is likely to move toward the west on later this week. On its anticipated track, Tropical Storm Don will make a big, clockwise loop west of the Azores during the next few days.

Tropical Storm Don Forms East of Windward Islands

Tropical Storm Don formed east of the Windward Islands on Monday.  An Air Force Reserve Hurricane Hunter reconnaissance aircraft found a small, but well defined center of circulation in a cluster of thunderstorms formerly designated Invest 91L.  Based on information from the recon plane, the National Hurricane Center classified the system at Tropical Storm Don.  At 5:00 p.m. EDT on Monday the center of Tropical Storm Don was located at latitude 11.2°N and longitude 52.6°W which put it about 595 miles (955 km) east of Trinidad.  Don was moving toward the west at 17 m.p.h. (28 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 1009 mb.

A Tropical Storm Warning has been issue for Grenada.  Tropical Storm Watches are in effect for Barbados, St. Vincent, the Grenadines and St. Lucia.

The reconnaissance plane found a small, tight center of circulation near the surface.  A thin band of showers and thunderstorms wrapped partially around the western side of the center.  Other thin bands of showers and thunderstorms were occurring north and west of the center.  There were fewer showers and thunderstorms in the eastern half of Tropical Storm Don.  The circulation of Tropical Storm Don is small and winds to tropical storm force only extend out about 25 miles (40 km) from the center of circulation.  Thunderstorms in the band west of the center of circulation were generating some upper level divergence but it was not well developed.

Tropical Storm Don will move through an environment that will be somewhat favorable for intensification during the next several days.  Don will move over water where the Sea Surface Temperature is near 29°C.  An upper level ridge east of Don is generating easterly winds which are blowing over the top of the tropical storm.  Those easterly winds are generating some vertical wind shear and the shear may partly explain why there are fewer showers and thunderstorms in the eastern half of the circulation.  The shear will also inhibit intensification, but Tropical Storm Don could strengthen during the next 24 to 48 hours.

A strong subtropical high over the Atlantic Ocean is steering Tropical Storm Don toward the west and a generally westward motion is expected to continue during the next several days.  On its anticipated track the center of Tropical Storm Don could pass south of Barbados on Tuesday.  Tropical Storm Don could move over the southern Windward Islands on Tuesday night.  Tropical Storm Don could bring gusty winds and locally heavy rain to the southern Windward Islands.  Flash floods could occur in areas of steep terrain, if they receive locally heavy rainfall.