Update on the Tropics

August 31, 2020

Taking a look at the tropics this morning, even though the 5-day outlook map looks busy there aren't any imminent threats to the US. The system off the east coast, Invest 90L, could bring stormy conditions to the Outer Banks as it passes but I don't have any real concerns about it. Invest 99L is the other red system in the Southeast Caribbean. This could develop some as it moves west but thankfully for the US it does not look like it will try to come north very much, it is mainly a concern for the northern coast of South America and Central America/Southern Mexico.

The tropical wave train keeps sending waves out into the Atlantic but for now there are no immediate concerns. The one to watch the closest is a wave that will come off of Africa over the next few days, with the NHC giving it a 30% chance of development over 5 days. It looks like if this one does try to develop it may be steered fairly far to the north and away from land but we'll have to wait and see. Looking at conditions in the eastern Atlantic there is some dry air north of these waves from the Saharan Air Layer and maybe a little bit of wind shear along their track and I think this is limiting development at this time. There are some hints of development here and there in the models but nothing to get too excited about at this point, definitely no real strong signals. That being said we're getting into the busiest part of the season so any disturbance needs to be watched closely for development.

That's all I have for today. I'll send out another update around the end of the week unless something significant happens between now and then.

Have a great week.

Chris

Severe Weather Possible Tomorrow for AL & TN, Update on the Tropics

August 27, 2020

The Storm Prediction Center has placed the northwestern third of Alabama and most of Tennessee in either slight or marginal risk areas for severe weather tomorrow due to lingering effects from Laura. These areas roughly correspond to a 5% and 2% chance of a tornado respectively. There are also 15% and 5% damaging wind risk areas as outlined in the third graphic. The simulated radar does not necessarily indicate how the situation will evolve so stay alert to local weather conditions.
 

Turning to the tropics, major hurricane Laura impacted the western Louisiana coast last night as a very strong category 4 hurricane. I'm sure you all have started to see some of the pictures and videos coming out of the area. We'll have to wait for the official report to see how strong it actually was, a category 5 is not out of the question. As residents in that area start to recover the rest of us need to stay prepared as we're still approaching the climatological peak of the season. On cue the NHC has identified two tropical waves that need to be watched for development on the 5-day tropical outlook. In addition to this ensemble models are hinting that there may be a series of several more waves that need to be watched over the next few weeks.

The consensus is that Laura was the start of what will be a very busy late summer and fall season as we head into September and October. We all need to stay prepared and keep watching. I'll keep you updated as the situation changes.
Stay safe and have a good Friday and great weekend.
Chris

Hurricane Laura Update - August 26, 2020

August 26, 2020

Hurricane Laura strengthened steadily yesterday and overnight and is now a strong category 2 hurricane with 110 mph sustained winds, 1 mph from a category 3. Edit: while I was writing this and as the graphic shows, Laura is now a 115 mph category 3 hurricane. It strengthened by over 45 mph in 24 hours. It is forecast to become a 130 mph category 4 storm in the next 12 hours and then weaken some before landfall due increasing wind shear near the coast. The track still calls for a landfall late tonight right on the Texas/Louisiana border which will thankfully spare the Houston metro area from a direct hit. Unfortunately this will probably be a devastating storm for Lake Charles, LA and the surrounding area. Some models still indicate that Laura could be even stronger than the official forecast, the NHC mentions this in their discussion, and some do not show weakening prior to landfall. The core of Laura is very large which helps it be able to fight off impediments such wind shear and dry air better than smaller storms. Weakening would be a blessing, but I'm concerned this may not happen.

In less there's something significant to report this will be my last update on Laura.

Have a great rest of the week.

Chris

Tropical Storm Laura Update - August 25, 2020

August 25, 2020

Tropical Storm Laura is now out in the open Gulf east of Cuba moving just north of west. With 70 mph winds it is just shy of hurricane strength. The forecast from the NHC calls for steady strengthening with Laura making landfall very early Thursday morning along the Texas/Louisiana border as a category 3 hurricane. As I have been mentioning the intensity forecast has been slowly ticking up and I think this trend will continue. Conditions aren't perfect for rapid intensification but they're pretty close and they will remain that way until landfall. A strong category 3 or category 4 hurricane is certainly possible. We may see the track shift just a little to the west as some of the track models have been consistent at taking the storm more to the south and west. So far the NHC has been pretty locked in on the TX/LA border so we'll see what happens. A landfall near the Houston metro area is still a possibility.

Today is the last day for preparations for people in the path of Laura. If you know anyone in that area you may want to get in touch with them and make sure they are taking action.

Through the weekend we'll need to start monitoring a tropical wave that will come off of Africa around Thursday. Some models are hinting that this may try to develop a little east of the Lesser Antilles early next week.

That's it for this morning, have a good day.

Chris

Marginal Tornado/Waterspout Threat Along The Panhandle

August 24, 2020

There is a threat of tornadoes and waterspouts moving onshore along the Florida Panhandle today due to conditions created by Tropical Storm Marco. The Panhandle has a marginal risk of severe weather associated with a 2% tornado threat as shown below. As I'm writing this there is a storm showing fairly strong rotation about 40 miles offshore of the Okaloosa Walton County line moving to the northeast. It's marked by the upside down pink triangle. These are well identified by radar and the NWS will issue warnings if there is a threat to land.

Stay safe.

Chris

Monday Morning Update on Laura and Marco

August 24, 2020

No major changes to the forecast for Marco and Laura this morning. Marco has weakened some overnight and will continue to do so on its approach to a Louisiana landfall tonight or early Tuesday.

Laura is moving just south of Cuba this morning and is nearing hurricane strength. The forecast is for it to move west-northwest remaining just south of the island, slowly strengthening before entering the Gulf early Tuesday. From Tuesday on it is forecast to strengthen steadily and make landfall near the Texas/Louisiana border late Wednesday or early Thursday as a strong category 2 hurricane. There is still some spread on the track and intensity guidance. It looks like the general track has consolidated fairly well and I wouldn't expect any major shifts, keeping in mind the cone is still wide at the landfall point. The intensity forecast is from a blend of models so you can think of it as sort of an average. What is concerning is that the HWRF, which is a high resolution hurricane specific model, has been consistently showing Laura becoming a very strong hurricane as it approaches landfall. This model can have a bias that over-strengthens storms in certain situations but it accurately predicted Michael and Dorian and has handled Marco well also. Because of this consistency it is becoming hard to ignore and I still think we'll see the intensity forecast increase some in the coming days. It is possible that the HWRF is wrong which would be good news for those in the path of Laura, we'll just have to wait and see.

That's it for this morning. The rest of the Tropical Atlantic is quiet for now but a tropical wave will come off the coast of Africa later this week that we'll need to keep an eye on as we end the month. It looks like it will be a rainy week along a lot of the Gulf Coast whether we're in the path of one of these storms or not. Have a great week.

Chris

Update on Laura and Marco - Sunday August 23, 2020

August 23, 2020

There hasn't been any major changes in the forecast for Laura or Marco over the last 12 hours. Laura is currently over the western edge of Hispaniola and should reemerge over water soon. Even though it is over land it looks fairly healthy. This is concerning because its future track may be along or just offshore of the southern coast of Cuba which could limit land interaction and allow for strengthening before it is in the open Gulf Monday night. The official forecast calls for Laura to be a strong category 2 hurricane with 100 mph winds at landfall near the Texas/Louisiana border late Wednesday or early Thursday. In their discussion the NHC cautions that their intensity forecast could be on the low side and to also expect adjustments to the track beyond 3 days, where and when it starts to make the right turn will make a big difference on where it makes landfall. There's really nothing to impede strengthening in the Gulf so unless Laura starts to fall apart across Cuba I think we will see significant upward adjustments to the intensity forecast in the coming days.

Marco is continuing its trek to the north-northwest across the Gulf and should be a hurricane soon. No major changes in the intensity or track forecasts are expected and Marco should make landfall in eastern Louisiana as a weak hurricane or strong tropical storm tomorrow.

Laura should be taken very seriously by everyone from Louisiana through the central Texas coast, I'd be watching closely from Mississippi also. The forecast cone still covers a large area and it is more likely than not that Laura will have major impacts where it makes landfall.

Enjoy your Sunday, I'll send out another update by tomorrow morning.

Chris