AmbergrisCaye.com Home Forums Talk Belize Weather Tropical Storms & Hurricanes Hurricane Michael

Satellite imagery indicated that there are some scattered shower and thunderstorm activity occurring across the southwestern Caribbean to the south of Jamaica. This is being caused by a trough of low pressure located over the central Caribbean that is pushing to the west. The western half of the Caribbean will need to be watched very closely for possible tropical development later this week and this weekend.

Even though we already have convection occurring across the southwestern Caribbean, the environmental conditions across much of the Caribbean is unfavorable for development. Wind shear values across much of the Caribbean are between 25 and 40 knots. The exception is across the far northwestern Caribbean where wind shear values are between 10 and 20 knots. So, tropical development seems unlikely for at least the next couple of days.

Beyond this, the tropical development chances may increase as energy from the trough of low pressure now over the central Caribbean builds up and combines with moisture across the western Caribbean. The big question is where exactly this possible tropical development occurs and whether environmental conditions will become favorable for development.

The model guidance are unanimous in forecasting some sort of tropical development to occur across the western Caribbean beginning late this week. With that said, each individual model continues to have different scenarios of what might occur late this week through this weekend and beyond.

The GFS model forecasts that tropical development may occur as soon as this weekend across the northwestern Caribbean. By next week, however, the GFS model forecasts that the energy with this system will split and head northeast towards the Bahamas with the model showing 3 separate low pressure centers. I think the GFS model may be suffering from its bias of convective feedback as well as its bias of pulling tropical systems too quickly to the north.

The Canadian model is much more consolidated with its tropical development forecast. It shows a low pressure system to develop over the northwestern Caribbean this weekend and forecasts it to move north-northwestward into the southeastern Gulf of Mexico during the early part of next week. By next Wednesday, the Canadian model forecasts this tropical system to be located over the southeastern Gulf of Mexico as a moderately strong tropical storm.

The European model forecasts that a low pressure system will form in the northwestern Caribbean late this week and this weekend. During next week, the European model seems to suggest that part of the energy of this system will be pulled to the northeast forming a new low pressure system near the US Southeast Coast while the original one dissipates. Ultimately, the European model forecasts

Looking at the various ensemble model guidance:

The GFS ensemble model guidance are strongly pointing towards tropical development to occur just west of Jamaica around Friday and Saturday. The ensemble members split by early next week with some of the members forecasting a track towards the southeastern Gulf of Mexico and other ensemble members forecasting a track towards the northwestern Bahamas. Beyond this, the ensemble spread is pretty large with a few members forecasting an eventual landfall on the western Gulf Coast around October 14, a few members forecasting either a northern Gulf Coast or Florida Peninsula landfall between October 12 and October 14 and a few ensembles showing a track near the US Southeast Coast.

The European ensemble guidance is forecasting up to a 45 percent chance for tropical development somewhere between Jamaica and Belize this weekend. Ultimately, the European ensemble guidance member spread is large, however, it is not as large as the GFS ensemble guidance. Some of the European ensemble guidance members forecast a landfall along the northern Gulf Coast between southeastern Louisiana and the Florida Panhandle on October 11. Other European ensemble members forecast a landfall somewhere on the Florida Peninsula between October 10 and 12 and then a track up the US East Coast.

Here Are My Thoughts: Tropical development over at least the next 2 to 3 days is highly unlikely due to unfavorable environmental conditions in the Caribbean. Beyond this, I am going with a 40 percent chance for tropical development in the western and northwestern Caribbean between about Friday and Sunday. A few factors may combine to lead to the development of a tropical system in the western and northwestern Caribbean very late this week and this weekend.

The first factor is the energy and moisture from a trough of low pressure now over the central Caribbean may build up this week over the western Caribbean.

The second factor is a piece of energy from Tropical Storm Leslie may break off and head southwestward into the western Caribbean by late this week which will add to the energy and moisture.

The third factor is a upper level ridge of high pressure is forecast to strengthen over the northeastern US and Mid-Atlantic States this weekend which will naturally lower barometric pressures from the Bahamas to the western Caribbean.

I do think, given the combination of all of the factors listed above, that we have a pretty good chance of seeing a tropical depression or tropical storm form in the western and northwestern Caribbean late this week and this weekend. As I already mentioned, I’m going with a 40 percent chance for this to occur.

The next question is where could this potential tropical system head. I think given the forecast weather pattern of a large upper level ridge of high pressure over the Northeastern United States that a track towards the northeast or east-northeast towards the Bahamas and out into the open Atlantic seems unlikely. Instead, a track to the north or northwest into the Gulf of Mexico seems more plausible given the weather pattern. This means if anything does form in the western and northwestern Caribbean this weekend, the northern and eastern Gulf Coast from Louisiana to the Florida Peninsula could be threatened by this system between October 11 and October 14.

Bottom line is that this potential western and northwestern Caribbean tropical system will be watched very closely, especially as we get into late this week and this weekend.

Crown Weather Services

For more information, check the daily Tropical Weather Outlook, click here.

The NOAA hurricane people say there is a small, <40% chance of the area in yellow circle, developing into a storm. I have circled the main cloud activity in blue, which is where the remnants of Kirk are still causing ITCZ swellups. But there is a lot of ITCZ activity in the Caribbean just north of Honduras, causing a lot of very humid, wet air, which is contributing to our rain patches.

A large cyclonic gyre, defined by a broad area of low pressure typical of this time of the year, covers a portion of Central America and the western Caribbean Sea. This system is accompanied by an extensive area of disorganized clouds and thunderstorms, and although surface pressures are relatively low in the area, upper-level winds are currently highly unfavorable for tropical cyclone formation. Environmental conditions could become less hostile this weekend and early next week, allowing for some slow development in this region as the system drifts northwestward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...30 percent.

USA National Weather Service

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Jeff Masters:

A broad area of low pressure called a Central American Gyre (see tweet below) was located over the southwestern Caribbean Sea on Wednesday afternoon, and was generating disorganized heavy thunderstorms over much of the southwest and central Caribbean. This system has the potential to develop into a tropical depression early next week as it drifts slowly northward, and it will bring dangerous heavy rains to portions of Central America this week.

Satellite loops on Wednesday showed that the low, which had not yet been given an "Invest" designation, had a surface circulation that was attempting to get organized a few hundred miles south-southwest of Jamaica. The heaviest thunderstorms lay well to the east, near Hispaniola. Wind shear was a prohibitively high 30 - 40 knots, due to the presence of a strong subtropical jet stream.

The shear will relent this weekend, when the subtropical jet stream is predicted to lift to the north so that it is positioned over Cuba. This will create a region of lower wind shear over the central and western Caribbean, and recent runs of the GFS and European model have been suggesting that a tropical depression could develop early next week. This was also predicted by over 30% of the 70 ensemble members of the 0Z Wednesday GFS and European models. Any tropical cyclone that develops is likely to become entangled with an upper-level low pressure system, making the system a large and slow-to-intensify sloppy mess of a storm that will primarily be a heavy rain threat. The track such a storm might take is anyone's guess at this point, and we'll just have to watch how the models depict the evolution of this potential threat in coming days.

For more information, check the daily Tropical Weather Outlook, click here.

The ITCZ activity in the Caribbean looks nasty, a lot of rain in there and it is coming our way. Presently, no rotation with it, but it could start to rotate, not necessarily, but it could. Early and late in the hurricane season, storms can start on our back door.

For more information, check the daily Tropical Weather Outlook, click here.

Recent satellite-derived wind data indicate that an area of low pressure is centered about 80 miles north of the coast of Honduras, however, the system is somewhat elongated and does not yet have a closed circulation. Heavier showers and thunderstorms have been developing near and to the east of the low's center during the past several hours, and extensive cloudiness and showers extend elsewhere across the western Caribbean Sea eastward over the Greater Antilles. Environmental conditions are expected to become gradually more conducive for further development, and a tropical depression is expected to form over the northwestern Caribbean Sea or the southern Gulf of Mexico over the weekend or early next week while the system moves slowly north-northwestward at about 5 mph. Interests in the Yucatan peninsula and western Cuba should monitor the progress of this system during the next several days. Regardless of tropical cyclone formation, this disturbance will continue to bring torrential rains to portions of Central America, the Yucatan peninsula, and western Cuba into next week.

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A broad area of showers and thunderstorms, currently over the Caribbean Sea, will drift into the Gulf of Mexico and may organize into a tropical depression or storm later this weekend and into next week.

Slow-moving and repeating downpours will continue the threat of flash flooding and mudslides into this weekend from Nicaragua, Honduras, Guatemala, Belize and southeastern Mexico to Jamaica, Cuba, Haiti, the Dominican Republic and Puerto Rico as well as the U.S. and British Virgin Islands.

During this weekend, as the mass of downpours begins to drift, an uptick in downpours is likely to spread over the Yucatan, Cuba and perhaps the Bahamas.

"This disturbance will move to near the Yucatan Channel between the Yucatan Peninsula and western Cuba by late Sunday, then move into the southern Gulf of Mexico or over the northern Yucatan on Monday," according to AccuWeather Hurricane Expert Dan Kottlowski.

Along its journey from the northwestern Caribbean to the central or eastern Gulf of Mexico, the disturbance may strengthen into a tropical depression or storm.

The next name on the list of tropical storms for the 2018 Atlantic hurricane season is Michael.

Fishing, shipping and petroleum interests in the Gulf of Mexico and coastal areas throughout the Gulf should monitor the progress of this tropical disturbance.

Accuweather

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MONITORING INVEST 91 L - PREPARING FOR POSSIBLE FLOODING As we enter the weekend, we advise Belizeans, particularly those living in flood prone areas, to stay alert and informed as our National Met Service and National Emergency Management Organization (NEMO) continue to monitor a broad area of disturbance in the Caribbean Sea which the Hurricane Center has named Invest 91L, and which has a high chance of tropical development late this weekend or early next week in the Caribbean Sea or southern Gulf of Mexico. Regardless of development, this will bring torrential rainfall to portions of Central America (including Belize) and the Yucatan Peninsula over the next few days, which can cause flooding. So far NEMO has NOT issued an ADVISORY, but will do so if and when it becomes necessary.

For more information, check the daily Tropical Weather Outlook, click here.

Invest 91-L Located Over The Northwestern Caribbean Continues To Become More Organized & Is Likely To Become A Tropical Depression Or A Tropical Storm By Sunday Or Monday

Invest 91-L Located Over The Northwestern Caribbean: Invest 91-L, which is an area of disturbed weather located over the northwestern Caribbean, continues to become more organized this morning. Satellite imagery, weather observations and radar loops indicate that even though this system does not yet have a well-defined circulation it is not too far from doing this. What is a little concerning to me is that Invest 91-L is organizing in the face of strong wind shear. Wind shear values are expected to decrease to 15 to 20 knots by Monday and remain at these levels through Wednesday. This is concerning because these more favorable conditions will likely lead to more robust development and intensification as Invest 91-L moves northward across the Gulf of Mexico on Monday, Tuesday and Wednesday.

The latest model guidance point to that the northern and northeastern Gulf Coast is most at risk from Invest 91-L with a likely landfall window between midday Wednesday and midday Friday somewhere between Cedar Key, Florida and New Orleans, Louisiana. As for forecast landfall intensity - the GFS, UKMET and HWRF models all forecast this system will be a strengthening hurricane at landfall. The European, SHIPS and LGEM models, on the other hand forecast a moderately strong tropical storm at the time of landfall. A reason why for the intensification right near landfall posed by all of the models is because they all forecast a turn to the northeast causing the storm to move with the upper level wind flow leading to nearly zero wind shear over it. This will be something that will need to be watched very closely.

Here Are My Thoughts: I think we are about 24 to 36 hours away from Invest 91-L becoming a tropical depression and maybe about 48 hours away from it becoming Tropical Storm Michael when it's near the Yucatan Channel and the southern Gulf of Mexico. Wind shear values by that time will be favorable for development and strengthening.

Invest 91-L Information:

Model Track Forecast:

Crown Weather Services

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For more information, check the daily Tropical Weather Outlook, click here.

TROPICAL CYCLONE 14 - MORE TORRENTIAL RAINS

The broad area of disturbance centered in the Northwestern Caribbean is almost certain to become Tropical Cyclone 14, and the Hurricane Center has now initiated advisories on it. It is expected to drift northward toward Yucatan Peninsula, then into the southern Gulf of Mexico by Monday. In the meantime, it is bringing torrential rainfall to portions of Central America (including Belize), Yucatan Peninsula and western Cuba over the next few days. The Hurricane Center says, "Rainfall totals of 3 to 7 inches are forecast over western Cuba, with 2 to 4 inches over the Yucatan Peninsula, Belize and northern Honduras through Tuesday." We advise residents and visitors throughout Belize, particularly in flood-prone areas, to keep monitoring reports from the Belize Met Service.

The storm should be named Hurricane Michael before the end of today.

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NEMO: NEW TROPICAL DEPRESSION TRACKING NORTH TO GULF COAST

As forecast, that area of disturbance centered in the northwestern Caribbean developed overnight into Tropical Depression 14, but, thankfully for Belize, it is headed north away from us. According to the National Meteorological Service of Belize, "Radar data from Belize and infrared satellite imagery indicate that the low pressure system centered just off the coast of the Yucatan Peninsula has continued to become better organized, with deep convection consolidating just to the northeast of the low-level center. (The Belize radar data was extremely helpful in locating the depression's center). The system continues to move northward slowly and farther away from Belize. Rainfall remains the only threat to Belize and portions of Central America, while tropical storm warnings are issued to portions of the Yucatan Peninsula and Western Cuba."

For more information, check the daily Tropical Weather Outlook, click here.

Hurricane Michael moves away from Belize

Most of Michael is now north of us... Tropical storm Michael is over the extreme northwest Caribbean moving northward away from Belize.





The satellite presentation of Michael has continued to improve overnight and this morning, with the center well embedded within an area of cold cloud tops. An eye is becoming apparent in visible imagery, and this was also confirmed by a recent SSMIS microwave overpass and the Air Force Reserve reconnaissance aircraft. The aircraft reported a minimum pressure around 982 mb during the most recent pass through the center, and also found flight-level winds that support upgrading Michael to a a 65-kt hurricane for this advisory.

Michael is forecast to be a dangerous major hurricane when it reaches the northeastern Gulf Coast on Wednesday, and life- threatening storm surge is possible along portions of the Florida Gulf Coast regardless of the storm's exact track or intensity. Residents in the storm surge and hurricane watch areas should follow any advice given by local officials, as storm surge and hurricane warnings will likely be issued later today.

Hurricane conditions will spread over portions of western Cuba this afternoon, where a hurricane warning is now in effect. Tropical storm conditions are expected over the northeastern Yucatan Peninsula and the Isle of Youth today.