UPDATED: SINT MAARTEN/CARIBBEAN - Invest 93-L which is located in the northwestern Caribbean is becoming better organized this morning (Sunday) as satellite imagery indicates there is deep convection occurring across the northwestern Caribbean, Crown Weather reported on Sunday.
“The low pressure system associated with Invest 93-L is located just east of the Yucatan Peninsula. Barometric pressures just east of Cozumel are falling and the environmental conditions have become more favorable for development as compared to yesterday.
“The amount of wind shear around Invest 93-L are 20 knots or less and there is a upper level high pressure system very close by to the center of circulation. In fact, a closer look at the upper air conditions around this system indicates that some upper level outflow could be developing, but it seems to be displaced just southeast of the low pressure center. In fact, that upper level high pressure system is forecast to move in tandem with Invest 93-L for at least the couple of days leading to a favorable environment for additional development and intensification.
“Bottom line is thatI think Invest 93-L will become a tropical depression as soon as Monday and likely will strengthen into a tropical storm by about Tuesday as this system moves towards either the northern or western Gulf of Mexico.
“Even though the model guidance has trended towards better agreement with each other, the individual models continue to have some very different outcomes on where Invest 93-L may head once it moves into the Gulf of Mexico. What is kind of “interesting” is that the latest forecast from the European model has trended a little towards the GFS model, but yet the Canadian model guidance has trended towards the European model.
“An analysis of water vapor satellite loops and the upper level winds across the Gulf of Mexico and the western Caribbean lends some credence to a northerly course towards the northern Gulf Coast, but probably not as far east as the GFS model which is forecasting a landfall in southern Alabama and the Florida Panhandle late Tuesday night.
“On the other hand, the European model guidance's forecast of a track into the western Gulf of Mexico may be too far west as water vapor satellite loops indicate a trough of low pressure is digging southward towards the western Gulf of Mexico which should steer any tropical system northward instead of westward.
“At this point, the Canadian model guidance may be a good “compromise” with a possible track north and northwestward across the Gulf of Mexico during Monday, Tuesday and Wednesday with a landfall somewhere along the upper Texas or Louisiana coast late Wednesday night or Thursday morning.
“The tropical cyclone track guidance is of little help as they are spread out with some of the guidance forecasting a track towards the Big Bend and Florida's west coast and other guidance forecasting a track towards the Texas coast.
“In addition, a majority of the European ensemble model member's track forecast for Invest 93-L are showing either a Louisiana or Texas impact from this system.
“Bottom line is that there continues to be a large amount of range in the model guidance and quite a bit of uncertainty regarding the eventual track of this system. My thinking right now is for a track towards either the middle and upper Texas coast or the southwestern or central coast of Louisiana for a landfall on Wednesday night or Thursday morning. With that said, I still cannot rule out a track northward towards the Florida Panhandle or the Alabama coastline.
“It is extremely likely that Invest 93-L will become a tropical depression sometime on Monday as it moves into the southern Gulf of Mexico. From there, I think that it is also very likely that it will become a tropical storm probably on Tuesday as it moves northwestward reaching the central Gulf of Mexico.
“Beyond this, I'm leaning towards a scenario that consists of a tropical storm with 45 to 60 mph winds to come ashore somewhere along either the middle or upper Texas coast or southwestern or southern Louisiana (between Matagorda Bay, Texas and Vermilion Bay, Lousiana) late Wednesday night or Thursday morning. The main reason why for the shift north in the forecast track is because the trough of low pressure digging southwestward towards the western Gulf of Mexico should be able to impart enough of a pull northward to steer this system towards Louisiana or the middle/upper Texas coast.
“As I have already mentioned, I'm still not ruling out a further eastward track towards the Florida Panhandle or southern Alabama and it is something that will be watched for closely.
“Forecast Impacts:Heavy rainfall with the threat for flooding is expected to continue for the next couple of days across Central America, the Yucatan Peninsula, the Cayman Islands, western Cuba and Jamaica.
“From there, the combination of a eastward moving frontal boundary and the abundant moisture from this tropical system is likely to lead to heavy rainfall and flooding on the eastern side of this system. This means that the highest threat for heavy rainfall and flooding will be across southern and southeastern Louisiana, much of Mississippi, much of Alabama, central and southern Georgia, the Florida Panhandle and the northern and central Florida Peninsula starting on Monday night and Tuesday morning and continuing through Wednesday and Thursday. In addition, squally weather with wind gusts of up to 60 mph are possible along the entire Texas and Louisiana coasts from Wednesday into Thursday,” Crown Weather reports.
(SATURDAY, JUNE 17, 2017) SINT MAARTEN/CARIBBEAN - Satellite imagery is showing a large area of disturbed weather that is located over the western and northwestern Caribbean. Weather analysis indicates there is a broad area of low pressure that is associated with this area of disturbed weather, Crown Weather reported on Saturday.
“Widespread shower and thunderstorm activity is occurring with the area of disturbed weather across much of the western Caribbean with heavy rainfall impacting parts of Central America, the Yucatan Peninsula, the Cayman Islands, western Cuba and Jamaica. Additional analysis reveals that the barometric pressures are falling across the northwestern Caribbean and the southern parts of the Gulf of Mexico. All of this tells me that this system is becoming better organized and I do think it will eventually become a tropical depression and then a tropical storm over the next few days or so as it moves from the northwestern Caribbean into the southern Gulf of Mexico. Finally, I fully expect to see this disturbed weather be designated Invest 93-L at some point this weekend.
“A review of the environmental conditions over the western Caribbean indicates that the shear has decreased from up to 40 knots at this time yesterday to current values of 20 to 30 knots. In addition, a small upper level ridge of high pressure is crossing Central America and this could lead to a further decrease in wind shear values and a more favorable environment for tropical development over the western Caribbean this weekend. At this point, I think we are at least 24 hours away from seeing this system try to really organize into a tropical depression. This means that I do not anticipate tropical development today with the development chances going way up by late Sunday and especially on Monday as this system moves into the southern Gulf of Mexico.
“Here are my thoughts: I think that there is a 85 percent chance that we will see a tropical depression form in the area from the western Caribbean into the southern Gulf of Mexico on either Sunday or Monday.
“The track forecast of the area of disturbed weather once it moves into the Gulf of Mexico is highly uncertain. There are two viable possibilities that I see –
“The first is for a large, weak and messy system that tracks west-northwestward towards northeast Mexico and the lower and middle Texas coast sometime on Wednesday or Thursday as it is influenced by a ridge of high pressure over the northern Gulf of Mexico.
“The second possible scenario is for enough of a trough of low pressure to sink southward into the southeastern United States leading to the area of disturbed weather being picked up and steered towards the Alabama or Florida Panhandle coastline.
“Even though there is a high amount of uncertainty in the forecast track – I am still leaning towards a large sloppy tropical storm with 40 to 60 mph winds track west-northwestward towards the western Gulf of Mexico on Monday and Tuesday. From there, this tropical storm is forecast to make landfall with 40-60 mph winds in northeastern Mexico or along the lower and middle Texas coast on either Wednesday or Thursday.
“Forecast Impacts: Heavy rainfall with the threat for flooding is expected this weekend into early next week across Central America, the Yucatan Peninsula, the Cayman Islands, western Cuba and Jamaica.
“From there, since this could be a large and wet system, heavy rainfall with the threat for flooding is forecast to impact a large area of the Gulf of Mexico, including southern Louisiana, south, central and southeast Texas and much of eastern Mexico starting around Tuesday and continuing through Wednesday, Thursday and Friday. In addition, squally weather with wind gusts of up to 60 mph are possible across northeast Mexico and along the lower and middle Texas coast during Wednesday and Thursday of next week,” Crown Weather concludes.