Tropical Weather Update - Tuesday August 17th

August 17, 2021

Now that Fred has moved on, let's take a look at the rest of the tropics. There are two more storms out there, Grace and Henri (pronounced in the French manner). Neither are a threat to us unless you're traveling somewhere. Grace could certainly be a problem for Mexico.

In the longer term there are two more tropical waves that will come off of Africa Friday and next Monday we'll need to watch, the existing waves don't look too threatening at the moment. Also, the GEFS is showing signals of something developing out of the deep Caribbean near Central America next week. I don't know if it is developing the southern end of tropical waves as they enter that area, if it's some other disturbance, or just a false signal. Sometimes the GFS/GEFS will see favorable conditions from the Eastern Pacific through the Caribbean and try to develop storms on our side instead of the Pacific when the East Pac is really the current hot spot. We'll have to watch if that trend continues and look for other models to pick up on it.

Going back to Fred, it was an interesting storm. It made a run at hurricane strength early yesterday but it never quite got there. Info on the ground from the landfall location both first hand and online reported fairly light winds (for a tropical storm) whereas locations to the east and west had winds nearing hurricane strength. The Panama City area took a pretty good punch which is interesting in that they were on the west side which is typically the weaker side. Land interaction can cause a storm to flare up right at landfall and it looks like that is what happened with Fred. There were only a few reports of tornadoes in Georgia so it is good that threat didn't materialize.

I have nothing else to report today but I'll probably send out another update around the weekend.

Have a great rest of the week!

Chris

Fred's Track Shifts East - 10 a.m. Advisory

August 16, 2021

With the 10 a.m. CDT advisory the track has shifted east again, now showing a landfall between Tyndall AFB and Mexico Beach. I thought we'd see some hurricane watches go up but not so. Forecast is now for 65 mph around landfall.

The tornado/waterspout threat continues but is currently isolated to the area near Apalachicola Bay.

Chris

Monday Morning Update on Fred

August 16, 2021

There were a few slight changes to the forecast for Fred overnight. The track has shifted to the east with the center of the forecast cone bringing Fred ashore on Panama CIty Beach just east of Hwy 79 as a 60 mph tropical storm. The Storm Prediction Center has increased the tornado risk from 2% to 5% and is expecting the first round of (potentially) tornado producing storms to come ashore near Apalachicola Bay between 9-11 a.m. EDT. A tornado watch was just issued for this area. Other impacts remain about the same.

The GFS and operational HWRF have backed off a bit on their intensification forecast from last night. Both models strengthen the storm just shy of hurricane strength prior to landfall. The intensity only version of the HWRF has the storm as a low end cat 1. There is an experimental model showing a similar solution as well but again the majority of models are not showing this outcome. The NHC did mention in their discussion that conditions will become slightly more favorable for strengthening and a hurricane hunter currently in the storm is finding lower pressures. I think these models are picking up on this possibility but they may be overdoing it, we'll see.

Unless there are significant changes to the track, intensity, or tornado risk this will be my last major update. I'm going to keep an eye out for tornado producing bands and send out updates on those when needed.

Grace and TD 8 near Bermuda don't look to be threats to us at this time but we'll talk more about those later.

Have a good day.

Chris

Re: Sunday Night Update on Fred

I should have waited 5 minutes...00Z HWRF hurricane model, one of the most reliable at times, also showing a minimal cat 1 right over my house but we're prepared.

On Sun, Aug 15, 2021 at 11:49 PM Chris Nabholz <cjnabholz@gmail.com> wrote:

August 15, 2021

Not much changed with the forecast for Fred with the 10 p.m. CDT advisory. The center of the track still brings the storm in just west of Walton/Bay county line as a 60 mph storm Monday evening. The main impacts will be at and to the east of the landfall location. There will definitely be some wind and storm surge along the coast but elsewhere rain and possibly tornadoes will be the main hazards. I completely forgot to mention the tornado threat during my last update but most of you know they are typically a hazard with landfalling storms, especially on the east side. Right now the risk is only 2% but we might see that go up tomorrow morning.

The 00Z operational models are starting to come in and one concerning item is that the GFS is showing Fred to be a category 1 hurricane at landfall. It is one run of one model so taking everything as a whole it is an outlier. Major global models like the GFS don't always do well on storm intensity although they do pretty good on the track. That being said, it is a generally reliable model so we'll need to see if this trend continues and watch if other models jump on board. There is virtually no other support for this at this time but it's not impossible so something to keep an eye on.

That's it for tonight.

Chris

Sunday Night Update on Fred

August 15, 2021

Not much changed with the forecast for Fred with the 10 p.m. CDT advisory. The center of the track still brings the storm in just west of Walton/Bay county line as a 60 mph storm Monday evening. The main impacts will be at and to the east of the landfall location. There will definitely be some wind and storm surge along the coast but elsewhere rain and possibly tornadoes will be the main hazards. I completely forgot to mention the tornado threat during my last update but most of you know they are typically a hazard with landfalling storms, especially on the east side. Right now the risk is only 2% but we might see that go up tomorrow morning.

The 00Z operational models are starting to come in and one concerning item is that the GFS is showing Fred to be a category 1 hurricane at landfall. It is one run of one model so taking everything as a whole it is an outlier. Major global models like the GFS don't always do well on storm intensity although they do pretty good on the track. That being said, it is a generally reliable model so we'll need to see if this trend continues and watch if other models jump on board. There is virtually no other support for this at this time but it's not impossible so something to keep an eye on.

That's it for tonight.

Chris

Sunday Morning Update on Fred and Grace

August 15, 2021

We're still watching the same two storms this morning. Starting with Fred, until just a few minutes ago it actually has not been a tropical cyclone at all for the better part of the last two days. While still shown as the "Remnants of Fred" on the map below, Fred has again become a tropical storm as of 8:40 a.m. EDT. The NHC issued a tropical storm watch for a portion of the AL and FL Panhandles earlier this morning and tropical storm warnings are expected with the 11 a.m. EDT advisory. After seeing the track shift west for 24 hours starting Friday evening we're now seeing the track shift east again. We'll see where the NHC puts the center for the next advisory. At 5 a.m. they noted it may be forming a little more to the north which would shift the track to the east again. Regarding intensity the expectation is for Fred to regain tropical storm strength, perhaps with winds as strong as 60 mph. Heavy rainfall will be the main impact but there will be minor storm surge concerns as well.

Looking briefly at Grace, which is struggling to maintain it's tropical cyclone status this morning, we're going to see it evolve in a similar fashion as Fred through Thursday. A lot of the current model guidance takes the storm across the Gulf to our west but we'll have to wait a few days to see if that holds.

That's it for now, I'll send out another update later today or tomorrow morning.

Chris

Late Friday Update on Fred and TD Seven

August 13, 2021

The 11 p.m. EDT update is out and with this forecast the NHC shifted the track a little more to the west with the center of the track showing landfall near Navarre, FL as a 60 mph tropical storm Monday night. The NHC noted that their forecast is a bit to the east of many models and that farther shifts west may be needed.

Due to wind shear most of the convection is well to the southeast of Fred over the northern Caribbean while the center of Fred, if there even is one, is somewhere over central Cuba. Due to this Fred isn't going to strengthen much until it pulls away from Cuba sometime tomorrow. Even though Fred will have a full day and a half over the Gulf persistent wind shear is expected to limit intensification. I was a little concerned earlier this evening when I saw the track and model trends. Some of the most recent model runs have settled back down and given the current poor state of the storm and continued presence of wind shear I am feeling better. We'll see what tomorrow brings but hopefully this trend continues.

I won't spend much time on it yet but Invest 95L became Tropical Depression Seven earlier today and will likely become Tropical Storm Grace by tomorrow. I didn't think we'd see it get named quite this soon but thankfully not much additional strengthening is expected in the short term. No concerns yet at all but we'll need to start paying more attention once Fred is out of the picture.

That's it for tonight. I'll probably send out another update by early evening tomorrow.

Have a great Saturday.

Chris