Tag Archives: Nicaragua

TD 16 Becomes Tropical Storm Otto

The National Hurricane Center named former Tropical Depression 16 as Tropical Storm Otto on Monday afternoon based on data from satellites.  At 4:00 p.m. EST the center of Tropical Storm Otto was located at latitude 11.3°N and longitude 79.2°W which put it about 315 miles (505 km) east of Bluefields, Nicaragua.  Otto was stationary.  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.

The structure of Tropical Storm Otto has not changed appreciably during today.  Most of the thunderstorms are occurring in bands north and west of the center of circulation.  There are fewer thunderstorms in the southeastern quadrant of the circulation.  Otto is a small tropical storm.  Winds to tropical storm force only extend out about 35 miles (55 km) from the center.  Thunderstorms are generating upper level divergence which is pumping mass out north and west of the tropical storm.

Tropical Storm Otto will move through an environment that will be favorable for intensification.  It will move over water where the Sea Surface Temperature will be near 29°C unless Otto moves so slowly that its own circulation mixes cooler water to the surface.  Southerly winds in the upper levels are generating moderate vertical wind shear, but those winds are expected to weaken.  When the vertical shear diminishes, Tropical Storm Otto will be likely to intensify and it could become a hurricane.

Tropical Storm Otto is currently in a region where the steering currents are weak.  However, a ridge of high pressure is forecast to build north of Otto, and the ridge is likely to steer the tropical storm toward the west.  On its anticipated track Tropical Storm Otto could approach the coast of Nicaragua and Costa Rica in 48 to 72 hours.

Tropical Storm Otto could be a hurricane by the time it reaches the coast of Nicaragua and Costa Rica.  Otto will be capable of bringing gusty winds and heavy rain to portions of Nicaragua, Costa Rica, northern Panama, Honduras, El Salvador and southern Guatemala.  The locally heavy rain could produce flash floods and mudslides in areas of steep terrain.

Tropical Depression 16 Develops Over Southwest Caribbean Sea

The National Hurricane Center upgraded Invest 96L to Tropical Depression 16 on Monday morning.  At 10:00 a.m. EST on Monday the center of Tropical Depression 16 was located at latitude 11.5°N and longitude 79.3°W which put it about 305 miles (495 km) east of Bluefields, Nicaragua.  Tropical Depression 16 was stationary.  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km).  The minimum surface pressure was 1002 mb.

An Air Force Reserve Hurricane Hunter aircraft investigated the area of low pressure over the southwestern Caribbean Sea on Sunday afternoon and it found a distinct surface center with a lower pressure.  When more thunderstorms formed near the center of circulation early on Monday, the National Hurricane Center designated the system as Tropical Depression 16.

The circulation of Tropical Depression 16 is fairly well organized.  It has a tight core and several bands of thunderstorms.  Most of the bands are occurring north and west of the center of circulation.  There are fewer thunderstorms in the southeastern quadrant of the circulation.  The thunderstorms north of the center are generating upper level upper level divergence.  Southerly winds appear to be inhibiting upper level divergence to the south of the tropical depression.

Tropical Depression 16 is in an environment that is slightly favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 29°C.  However, the depression and its precursor have been over the same area for almost a week.  So, the winds in Tropical Depression 16 are gradually mixing cooler water to the surface.  An upper level ridge to the east and an upper level trough to the west are generating southerly winds which are blowing across the top of the depression.  The southerly winds are generating moderate vertical wind shear and they are inhibiting upper level divergence to the south.  The mixed environmental factors will limit intensification in the short term.  The upper level winds are forecast to weaken in a day or two and more intensification could occur when that happens.  Tropical Depression 16 is likely to intensify into a tropical storm and it could become a hurricane later this week.

The steering currents are weak around Tropical Depression 16 and it may move little during the next 24 to 36 hours.  A ridge of high pressure is forecast to build north of the depression and the ridge is forecast to steer it slowly toward the west later this week.  Tropical Depression 16 could approach the coast of Nicaragua in about three days.  It could be a hurricane at the time.

Invest 90L Organizing North of Panama

The structure of the low pressure system designated as Invest 90L became better organized on Saturday over the southwestern Caribbean Sea north of Panama.  At 7:00 p.m. EDT on Saturday the center of Invest 90L was located at latitude 10.8°N and longitude 80.9°W which put it about 220 miles (355 km) east-southeast of Bluefields, Nicaragua.  Invest 90L was moving toward the east at 3 m.p.h. (5 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (70 km/h).  The minimum surface pressure was 1006 mb.

More thunderstorms developed closer to the center of circulation on Saturday.  A band of stronger thunderstorms formed south of the center and a second band of storms developed northeast of the center.  Other rainbands appeared to be forming in other areas of the circulation.  Storms in the band northeast of the center began to produce upper level divergence that was pumping mass away.  An improved convective structure could be a indication that Invest 90L is developing into tropical depression.

The atmospheric environment became more favorable for tropical development on Saturday.  Upper level southwesterly winds which were blowing across the top of the low pressure system weakened on Saturday  and the vertical wind shear lessened.  Less shear allowed more thunderstorms to develop and persist.  Since Invest 90L has meandered over the same part of the southwestern Caribbean Sea for several days, it has mixed slightly cooler water to the surface.  However, the water in that part of the Caribbean Sea is very warm and Invest 90L is moving over water where the Sea Surface Temperature is still near 29°C.  The environment is favorable for development of a tropical cyclone and Invest 90L could become a tropical depression or a tropical storm at any time.

Invest 90L is located underneath an upper level ridge and the steering currents are weak.  The low pressure system drifted toward the east on Saturday and some models are suggesting that Invest 90L could make a slow counterclockwise loop over the southwestern Caribbean Sea during the next few days.

Invest 90L Meandering Over Southwest Caribbean Sea

An area of low pressure designated as Invest 90L has meandered over the southwestern Caribbean Sea during the past several days.  At 7:00 p.m. EST on Thursday the center of Invest 90L was located at latitude 12.3°N and longitude 81.3°W which put it about 170 miles (275 km) east of Bluefields, Nicaragua.  Invest 90L was moving toward the west at 3 m.p.h. (5 km/h).  The maximum sustained wind speed was 25 m.p.h. (40 km/h) and there were wind gusts to 35 m.p.h. (55 km/h).  The minimum surface pressure was 1006 mb.

Invest 90L consists of a broad area of low pressure over the southwestern Caribbean Sea.  There is a definite area of counterclockwise rotation, but the is no well defined core at the center of the low.  There is a swirl of low clouds and showers at the center of Invest 90L, but there are no thunderstorms near the center.  Thunderstorms form and dissipate in bands around the periphery of the circulation.

The environment around the southwestern Caribbean Sea is not as favorable for the development of a tropical cyclone as it was earlier this week.  Invest 90L is moving over water where the Sea Surface Temperature is near 29°C.  However, northerly winds blowing across the Gulf of Mexico have transported drier air over the northwestern Caribbean Sea.  The drier air has not reached Invest 90L, but the drier air is just to the northwest of the low pressure system.  An upper level trough over the Gulf of Mexico is producing southwesterly winds which are blowing over the top of Invest 90L.  Those winds are generating moderate vertical wind shear which is inhibiting the organization of the low pressure system.  Even with the inhibiting factors the National Hurricane Center is indicating that the probability of the formation of a tropical cyclone during the next five days is 70%.

The fact that there is only a low level circulation means that Invest 90L is being steering by winds closer to the surface.  The winds in the lower levels have been pushing the low pressure system very slowly toward the west.  Guidance from numerical models suggests that Invest 90L could meander over the southwestern Caribbean Sea for several more days.

Possible Tropical Development Over the Southwest Caribbean Sea

A weak trough of low pressure over the Southwestern Caribbean Sea has the potential to develop into a tropical cyclone during the next few days.  The National Hurricane Center is stating that there is a 70% probability of the formation of a tropical cyclone during the next five days.  A broad trough of low pressure stretches from near Panama to east of Nicaragua.  There is not a well defined center of low pressure within the broader trough.  There were more thunderstorms earlier today, but many of them weakened on Monday evening.  A few more thunderstorms developed north of Panama during the past several hours.

The environment over the southwestern Caribbean Sea is favorable for intensification.  The Sea Surface Temperature of water in that part of the Caribbean Sea is around 29°C.  There is an upper level ridge over the area.  The winds are weaker in the center of the ridge and there is little vertical wind shear in that part of the atmosphere.  The ridge providing a source of upper level divergence which is allowing the surface pressure to decrease slowly.

Several numerical models are suggesting that a tropical cyclone could develop during the next few days.  The models do differ on exactly when and where the tropical cyclone could form.  The probability of development will be higher if the area of lower pressure remains over the water.  However, if the trough of low pressure drifts closer to the coast of Nicaragua, then the interaction of the circulation with land could inhibit the formation of a tropical cyclone.  Even if a tropical cyclone does not form, the trough could produce locally heavy rain over parts of Panama, Nicaragua and Honduras.