2017 indicators: SST's / MSLP / SAL / Steering / Instability

[Hammy]

Hurricane Harvey=Will hopefully make people stop comparing 2017 to 2013 once and for all

we were on the way to having a storm like this in 2013. Fernand. Started to rapidly intensify but ran into Veracruz. It had found a small area of favorable conditions.

Harvey simply had 2 days more over the water. That extra time made all the difference. Similar conditions, but slightly different positioning.

Not sure where we are on the season to date ACE, but this (like 1970 and 1983) show that maybe ACE is not the best judge of an active season. 2007 had below average ACE, yet it felt very active because many quick spin ups ran into land as cat 1s producing little ACE

1985 too. Very average at best ACE, but lots of landfalling storms in the US caused that year to feel very active. Perception is reality.

-Andrew92

1985 is an interesting comparison--active July in the EPAC, and the Atlantic had no named storms form during the entire first half of September, and only Gloria in the MDR (which struggled until about 55W.) And the storms were fairly evenly distributed as well rather than having any periods of multiple active systems.

[wxmann_91]

Hurricane Harvey=Will hopefully make people stop comparing 2017 to 2013 once and for all

we were on the way to having a storm like this in 2013. Fernand. Started to rapidly intensify but ran into Veracruz. It had found a small area of favorable conditions.

Harvey simply had 2 days more over the water. That extra time made all the difference. Similar conditions, but slightly different positioning.

Not sure where we are on the season to date ACE, but this (like 1970 and 1983) show that maybe ACE is not the best judge of an active season. 2007 had below average ACE, yet it felt very active because many quick spin ups ran into land as cat 1s producing little ACE

Re 2013: also Ingrid, had it not gotten sheared apart by Manuel in the EPAC.

2007 felt active because of Dean and Felix. Tough to judge a season when it has such a dramatic peak then decay (mid-September onwards was shut down by the TUTT).

[TheStormExpert]

Hurricane Harvey=Will hopefully make people stop comparing 2017 to 2013 once and for all

we were on the way to having a storm like this in 2013. Fernand. Started to rapidly intensify but ran into Veracruz. It had found a small area of favorable conditions.

Harvey simply had 2 days more over the water. That extra time made all the difference. Similar conditions, but slightly different positioning.

Not sure where we are on the season to date ACE, but this (like 1970 and 1983) show that maybe ACE is not the best judge of an active season. 2007 had below average ACE, yet it felt very active because many quick spin ups ran into land as cat 1s producing little ACE

But that was in the BoC, I thought the Gulf was quite unfavorable in 2013?

[Alyono]

Hurricane Harvey=Will hopefully make people stop comparing 2017 to 2013 once and for all

we were on the way to having a storm like this in 2013. Fernand. Started to rapidly intensify but ran into Veracruz. It had found a small area of favorable conditions.

Harvey simply had 2 days more over the water. That extra time made all the difference. Similar conditions, but slightly different positioning.

Not sure where we are on the season to date ACE, but this (like 1970 and 1983) show that maybe ACE is not the best judge of an active season. 2007 had below average ACE, yet it felt very active because many quick spin ups ran into land as cat 1s producing little ACE

But that was in the BoC, I thought the Gulf was quite unfavorable in 2013?

Gulf produced several storms that year. Andrea, Barry, Fernand, Ingrid, Karen

[TheStormExpert]

we were on the way to having a storm like this in 2013. Fernand. Started to rapidly intensify but ran into Veracruz. It had found a small area of favorable conditions.

Harvey simply had 2 days more over the water. That extra time made all the difference. Similar conditions, but slightly different positioning.

Not sure where we are on the season to date ACE, but this (like 1970 and 1983) show that maybe ACE is not the best judge of an active season. 2007 had below average ACE, yet it felt very active because many quick spin ups ran into land as cat 1s producing little ACE

But that was in the BoC, I thought the Gulf was quite unfavorable in 2013?

Gulf produced several storms that year. Andrea, Barry, Fernand, Ingrid, Karen

3 of the 5 were in the BoC. They're also weak too.

[Alyono]

But that was in the BoC, I thought the Gulf was quite unfavorable in 2013?

Gulf produced several storms that year. Andrea, Barry, Fernand, Ingrid, Karen

3 of the 5 were in the BoC. They're also weak too.

only weak because they ran out of time, not because of unfavorable conditions

[CYCLONE MIKE]

Haven't really been paying any attention to the overall conditions and talk about the atlantic since all this with Harvey started. Now that we're just around the corner from September is thinking still the same, that September looks to be pretty inactive?

[TheStormExpert]

Gulf produced several storms that year. Andrea, Barry, Fernand, Ingrid, Karen

3 of the 5 were in the BoC. They're also weak too.

only weak because they ran out of time, not because of unfavorable conditions

Karen died before it reached the northern Gulf coast in early October that year. Otherwise you're probably right. The Gulf was the only favorable region in the Atlantic that year it seems.

What are your thoughts on the remainder of this season?

[TheStormExpert]

Haven't really been paying any attention to the overall conditions and talk about the atlantic since all this with Harvey started. Now that we're just around the corner from September is thinking still the same, that September looks to be pretty inactive?

If you believe the GFS it'll be an active start, but we know better than that.

[Ntxw]

Philip Klotzbach ✔ @philklotzbach
Table of all 25 Cat 4-5 US landfalling hurricanes on record sorted by pressure-#Harvey tied for 14th lowest w/ Hazel (1954) & Georgia (1898)

 https://twitter.com/philklotzbach/status/901454599541805058

[CrazyC83]

we were on the way to having a storm like this in 2013. Fernand. Started to rapidly intensify but ran into Veracruz. It had found a small area of favorable conditions.

Harvey simply had 2 days more over the water. That extra time made all the difference. Similar conditions, but slightly different positioning.

Not sure where we are on the season to date ACE, but this (like 1970 and 1983) show that maybe ACE is not the best judge of an active season. 2007 had below average ACE, yet it felt very active because many quick spin ups ran into land as cat 1s producing little ACE

1985 too. Very average at best ACE, but lots of landfalling storms in the US caused that year to feel very active. Perception is reality.

-Andrew92

1985 is an interesting comparison--active July in the EPAC, and the Atlantic had no named storms form during the entire first half of September, and only Gloria in the MDR (which struggled until about 55W.) And the storms were fairly evenly distributed as well rather than having any periods of multiple active systems.

Reanalysis will probably find 1985 had additional storms, since we may not have figured out satellite signatures yet and may have mis-analyzed marginal storms.

[CrazyC83]

Oops in wrong thread.

[WeatherHoon]

Are there really any detrimental signs for an inactive September? The only thing that I see is a suppressed MJO signal entering the Atlantic soon, and I'm not really convinced it will truly put a cap on development for most of September.

[TheStormExpert]

Are there really any detrimental signs for an inactive September? The only thing that I see is a suppressed MJO signal entering the Atlantic soon, and I'm not really convinced it will truly put a cap on development for most of September.

SAL, mid-level dry air which has seemed to picked up a little in the Tropical Atlantic, and some wind shear (at least for now). This could be bad news like we saw with the wave that spawned Harvey as it will increase U.S. threats if they fail to develop right away. Like originally thought way back at the beginning of this year the Western Atlantic is more favorable than the Tropical Atlantic.

[NDG]

we were on the way to having a storm like this in 2013. Fernand. Started to rapidly intensify but ran into Veracruz. It had found a small area of favorable conditions.

Harvey simply had 2 days more over the water. That extra time made all the difference. Similar conditions, but slightly different positioning.

Not sure where we are on the season to date ACE, but this (like 1970 and 1983) show that maybe ACE is not the best judge of an active season. 2007 had below average ACE, yet it felt very active because many quick spin ups ran into land as cat 1s producing little ACE

But that was in the BoC, I thought the Gulf was quite unfavorable in 2013?

Gulf produced several storms that year. Andrea, Barry, Fernand, Ingrid, Karen

The question was regarding the BOC which was probably the only favorable area in the GOM, the only two storms that formed in the GOM (not the BOC) were Andrea and Karen, the rest developed in the BOC.
Karen was killed by shear and dry air as it approached the central and northern GOM, for early October that was very unusual.
Even Ingrid at one struggled, it had a whole 120 hour over open water in the BOC & SW GOM to become stronger than a Cat 1 but windshear kept it in check.

I still see no comparison to 2013.

[NDG]

Haven't really been paying any attention to the overall conditions and talk about the atlantic since all this with Harvey started. Now that we're just around the corner from September is thinking still the same, that September looks to be pretty inactive?

IMO there is no reason to believe that September will be inactive. MJO is forecasted is currently getting a little active on phase 2, this usually gets tropical waves a little stronger over Africa/eastern Atlantic, so even if they don't develop over the MDR they could be a threat down the road in the western Basin where dry air has not been a problem for development.
So far this August we have 3 hurricanes, many back in July did not see that coming.

[TheStormExpert]

Also those 3 named storms that developed this month (Franklin, Gert, Harvey) all became hurricanes.

[NDG]

:uarrow: Also those 3 named storms that developed this month (Franklin, Gert, Harvey) all became hurricanes.

Good point!!
No problem with those 3 becoming hurricanes, they would had struggled if conditions would had been the same as 2013, at least in the western Basin.

[TheStormExpert]

And the above average and now deadly hurricane season continues.

 https://twitter.com/philklotzbach/status/901906214077861888

[Hammy]

I'll throw my two cents in here on a statistical aspect. Alyono pointed out in I believe earlier in this thread (or it could've been another) that perhaps ACE isn't a good indicator of activity and I'm thinking that might be true, because Harvey will have only added about 10 points or so, despite being a Cat 4, thanks to the shorter lifespan (as it wasn't a long tracking Cabo Verde system). We're currently at about 24 ACE or so, so what's to say we don't have 4 similar storms to Gert and Harvey, Cat 3s and 4s that form further west, and a say another Cat 1 in the Gulf or western Caribbean, and then maybe five more tropical storms--we could easily end up with something like 17/7/4 and around 55-65 ACE in that setup--perhaps we need something like ACE that is based solely on the peak intensity.