ATL: IRMA - Models

[Aric Dunn]

Alyono,

As someone who lived through Andrew. Is there a legitimate possibility of Irma doing the same as Andrew and realistically barreling into SFL?

Im not him.. but the answer is a definite yes !

just no Aric.

i made a edit lol.. I meant it as only a possible track into to florida.

[caneman]

all models shifted westward with regards to the USA EXCEPT for the EC

Not liking seeing these massive flips from it

That said, the threat to the Leeward Islands is most certainly INCREASING. All models have shifted closer to the Leewards

Yep. 12 short hours ago it took out the Carolinas. One run right now means exactly nothing.

2 or 3 days ago, The Euro had it going thru the Keys.That is why we use a blend. It could still flip back west with the other models. So, everyone take a deep breath. Wait to we're at 120 hours

[AutoPenalti]

Alyono,

As someone who lived through Andrew. Is there a legitimate possibility of Irma doing the same as Andrew and realistically barreling into SFL?

Im not him.. but the answer is a definite yes !

just no Aric.

Why not Alyono? So far we've seen during the short term forecasts that it's a bit slower and further WSW, anything after 5 days is a toss-up. I feel that everyone along the eastern seaboard from SE FL to Maine are at equal chances of some sort of effect.

[Ken711]

Levi Cowans latest report.

https://www.youtube.com/watch?v=ocnoepCHK1I

[stormreader]

Finally! An out to sea run.. Figured this was coming. It was just a matter of time

An out to sea run does not mean an out to sea storm. We're still in the 10 day range here. It looks pretty certain that Irma will be very close to Florida. That's about it when it comes to confidence. In that case, I think the odds are weighted in favor of a U.S. Landfall. Going to keep my own personal "Irma window" open for Cape Fear North Carolina--to--North Cuban Coast. Still think there is a reasonable chance that Irma misses trough altogether. Thus keeping that southerly track as an option.

[forecasterjack]

12Z ECMWF showed a solution precariously close to disaster. With a cutoff ULL in the Mid Atlantic and a high trying to build over Atlantic Canada (But being squished by Greenland ULL), you're crazy close to a bad situation. If that DC ULL is any stronger, that Atlantic ridge any stronger, that Greenland ULL any weaker, you get the left hook displayed by some of the GFS runs. WAY too early to hone in on specific solutions, but latest synoptic trends are concerning to say the least.

[Alyono]

GFS is too fast for a recurve. Trough draws it into the coast. EC sped up slightly, to a speed just right to allow for a recurve. Any faster, and it hits the coast. Any slower, Irma misses the trough. Chances may not be good that it can repeat this next time

[stormreader]

Oh yay!!! One European run OTS and its all clear according to certain posters

The models are still having a bit of trouble with this trough/ridge scenario which could change..what we know for sure is there will be a Cat 4-Cat 5 in the Bahamas next week..who knows where it goes from there

Remember the latest GFS run had a run into Delmarva so anyone who says it's all clear is a fool..the entire east coast is still in pkay

Tuesday we will have a better idea when it's north of the islands

I honestly try to ignore it now. People have always been like this and it will most likely never change. But it's important to not sound all clear alarms over one run.

I actually feel the complete opposite.
I am not relieved by this run at all. For better or worse, the Euro at least looked fairly consistent (as consistent as synoptics can be 9-10 days out), and then threw a completely different picture out. As others have written, the setup is complex and the models haven't locked in.

Relieved? Hardly. The only thing we DO have a degree in confidence in is that the Leewards could be under threat and possibly the Bahamas too. 5 days the Euro and HWRF has this thing sitting around 21-22N 69-70W, a fairly threatening location. If the Euro repeats another 2 or 3 times in a row, then that will be comforting.

Yes. What we do have high confidence in is the path to the Bahamas and very near Florida. After that.....I don't know how anyone could feel a measure of relief with that track. Think...You're believing in a last minute deep north turn on a 10 day forecast. It's really quite a dangerous forecast for the East coast and possibly even the GOM.

[AxaltaRacing24]

GFS is too fast for a recurve. Trough draws it into the coast. EC sped up slightly, to a speed just right to allow for a recurve. Any faster, and it hits the coast. Any slower, Irma misses the trough. Chances may not be good that it can repeat this next time

So it's really not an "east shift" but it connected to the trough this time. But with that pattern one day slower or faster and it's a FL through NC hit. Dangerous pattern shown on the 12z.

[NJWxHurricane]

Finally! An out to sea run.. Figured this was coming. It was just a matter of time

An out to sea run does not mean an out to sea storm. We're still in the 10 day range here. It looks pretty certain that Irma will be very close to Florida. That's about it when it comes to confidence. In that case, I think the odds are weighted in favor of a U.S. Landfall. Going to keep my own personal "Irma window" open for Cape Fear North Carolina--to--North Cuban Coast. Still think there is a reasonable chance that Irma misses trough altogether. Thus keeping that southerly track as an option.

7 days*

[hohnywx]

The Euro Ens are coming in west of 00z...should be a red flag against the Euro OP

[forecasterjack]

Also of note is how favorable the environment will be in the Bahamas. SST's are super warm, ML RH is crazy high, and shear is limited/none. While the ECMWF shows some westerly 300mb flow, I think by then the storm's ULAC will be established enough to mitigate any interference from that. At the moment, confidence is unusually high in a high end cat 4 or even cat 5 storm in this area. The real uncertainty emerges once you get potential interaction with the mid latitude synoptic dynamics. Trough, ridge, cutoff, RWT influences etc. are all complicated and the models don't usually do a good job handling them. Hence the uncertainty there. But the uncertainty is unusually low that we'll get a crazy strong storm in/near the Bahamas.



All that's available here: https://weather.us/model-charts/euro/72 ... 0600z.html just use menus to adjust parameters

[Steve]

I'm finding this year, inside of 5. I realize that's anecdotal, but I do run them pretty much every day.

In general, yes. I meant inside Day 7 only specifically for Irma (the close to Lesser Antilles -> SE Bahamas track). Large, strong hurricanes in the deep tropics under a ridge usually have higher confidence track forecasts.

I gotcha. For me, specifically with Irma, I like the models for the next 90 hours or so. They almost are in full agreement with an overall spread inside of 150-200 miles. Courtesy of Mike's Weather Page (didn't want to hotlink):

EC Ensembles (but from 00z) which did telegraph the operational
http://www.weathernerds.org/tc_guidance ... g?56739613

GFS Ensembles 12Z - 100% landfall with the ones he charts
http://www.weathernerds.org/tc_guidance ... g?64355680

18Z lesser Guidance
https://www.tropicaltidbits.com/stormin ... latest.png

SFWMD
https://my.sfwmd.gov/sfwmd/common/image ... s/storm_11

Literally everything is in line for 3-4 days. EC a little south of the consensus at the Islands. So I agree to that point. But I think the 5-8 days is fully suspect. Then will the Canadian high EC shows be too slow to stop Irma or is it working on becoming a block? I guess I have less confidence with Irma than you do in the 5-7 day range. I think it will be a Cat 4 and in the SW Atlantic at that point like the models generally do. But coming from S, SSE, SE? There's too much disparity. My take for now is there is a lot of flipping at this point except the GFS for now has settled on a mid-Atlantic system for a few runs. It will probably change and change again after that as it has adjusted northern upper patterns considerably. I guess I'm good for now with the models probably into about Wednesday am with a system north of Puerto Rico and coming up from the ESE at that point.

I forgot to add that it's notable that almost every model has us dealing with a major hurricane for at least 8 days. It will possibly get to Category 5 which is the benchmark for the strongest storms. I anticipate people's anxiety levels will be getting high early next week for a very large storm with a solid potential for landfalling as a 3, 4 or 5. Harvey woke people up. Stay ahead of the game if you're on the East Coast and if the majority of the models continue to indicate potential US Landfall.

[weathaguyry]

Timing will be absolutely key, and will make the difference between catastrophe and high waves+rip currents

[wxmann_91]

I'm finding this year, inside of 5. I realize that's anecdotal, but I do run them pretty much every day.

In general, yes. I meant inside Day 7 only specifically for Irma (the close to Lesser Antilles -> SE Bahamas track). Large, strong hurricanes in the deep tropics under a ridge usually have higher confidence track forecasts.

I gotcha. For me, specifically with Irma, I like the models for the next 90 hours or so. They almost are in full agreement with an overall spread inside of 150-200 miles. Courtesy of Mike's Weather Page (didn't want to hotlink):

EC Ensembles (but from 00z) which did telegraph the operational
http://www.weathernerds.org/tc_guidance ... g?56739613

GFS Ensembles 12Z - 100% landfall with the ones he charts
http://www.weathernerds.org/tc_guidance ... g?64355680

18Z lesser Guidance
https://www.tropicaltidbits.com/stormin ... latest.png

SFWMD
https://my.sfwmd.gov/sfwmd/common/image ... s/storm_11

Literally everything is in line for 3-4 days. EC a little south of the consensus at the Islands. So I agree to that point. But I think the 5-8 days is fully suspect. Then will the Canadian high EC shows be too slow to stop Irma or is it working on becoming a block? I guess I have less confidence with Irma than you do in the 5-7 day range. I think it will be a Cat 4 and in the SW Atlantic at that point like the models generally do. But coming from S, SSE, SE? There's too much disparity. My take for now is there is a lot of flipping at this point except the GFS for now has settled on a mid-Atlantic system for a few runs. It will probably change and change again after that as it has adjusted northern upper patterns considerably. I guess I'm good for now with the models probably into about Wednesday am with a system north of Puerto Rico and coming up from the ESE at that point.

I think that's fair. General point being fairly high confidence in the near-term through the SW Atlantic, but anything after that remains up in the air and not subject to change between individual model runs and solutions.

[Aric Dunn]

GFS is too fast for a recurve. Trough draws it into the coast. EC sped up slightly, to a speed just right to allow for a recurve. Any faster, and it hits the coast. Any slower, Irma misses the trough. Chances may not be good that it can repeat this next time

So it's really not an "east shift" but it connected to the trough this time. But with that pattern one day slower or faster and it's a FL through NC hit. Dangerous pattern shown on the 12z.

this run was not just a trough its also closed on a stonger low over canada that seemed to extend another piece of energy that drew it north. though I dont have the hi res Euro .. but the stronger low is quite apparent compared to 00z run.. so the synoptics are not even the same and its not just the forward speed of the hurricane.

[TheStormExpert]

The Euro Ens are coming in west of 00z...should be a red flag against the Euro OP

Are you able to post images?

[forecasterjack]

GFS is too fast for a recurve. Trough draws it into the coast. EC sped up slightly, to a speed just right to allow for a recurve. Any faster, and it hits the coast. Any slower, Irma misses the trough. Chances may not be good that it can repeat this next time

So it's really not an "east shift" but it connected to the trough this time. But with that pattern one day slower or faster and it's a FL through NC hit. Dangerous pattern shown on the 12z.

this run was not just a trough its also closed on a stonger low over canada that seemed to extend another piece of energy that drew it north. though I dont have the hi res Euro .. but the stronger low is quite apparent compared to 00z run.. so the synoptics are not even the same and its not just the forward speed of the hurricane.

High res Euro: https://weather.us/model-charts/euro/72 ... 0600z.html can click the map to zoom in or click into edges to pan. Use menus to adjust parameters and times. And btw, it's all free

[forecasterjack]

ECMWF ensembles. Uncertainty abounds.

[Aric Dunn]

So it's really not an "east shift" but it connected to the trough this time. But with that pattern one day slower or faster and it's a FL through NC hit. Dangerous pattern shown on the 12z.

this run was not just a trough its also closed on a stonger low over canada that seemed to extend another piece of energy that drew it north. though I dont have the hi res Euro .. but the stronger low is quite apparent compared to 00z run.. so the synoptics are not even the same and its not just the forward speed of the hurricane.

High res Euro: https://weather.us/model-charts/euro/72 ... 0600z.html can click the map to zoom in or click into edges to pan. Use menus to adjust parameters and times. And btw, it's all free

cool thanks.