Hurricane Joaquin

[Superstorm93]

....By tomorrow evening or so, I bet we have a MH on our hands....

 

Crap ton of flights scheduled. Extra resources due to the lack of a season 

 

 

 

000

NOUS42 KNHC 291432

REPRPD

WEATHER RECONNAISSANCE FLIGHTS

CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.

1030 AM EDT TUE 29 SEPTEMBER 2015

SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)

VALID 30/1100Z TO 01/1100Z OCTOBER 2015

TCPOD NUMBER.....15-126

I. ATLANTIC REQUIREMENTS

1. TROPICAL STORM JOAQUIN

FLIGHT ONE -- TEAL 73 FLIGHT TWO -- NOAA 49

A. 30/1130Z A. 01/0000Z

B. AFXXX 0311A JOAQUIN B. NOAA9 0411A JOAQUIN

C. 30/0715Z C. 30/1730Z

D. 26.3N 72.4W D. NA

E. 30/1100Z TO 30/1400Z E. NA

F. SFC TO 10,000FT F. 41,000 TO 45,000FT

FLIGHT THREE -- TEAL 74 FLIGHT FOUR -- NOAA 49

A. 30/2330Z A. 01/1200Z

B. AFXXX 0511A JOAQUIN B. NOAA9 0611A JOAQUIN

C. 30/1930Z C. 01/0530Z

D. 26.3N 73.1W D. NA

E. 30/2300Z TO 01/0200Z E. NA

F. SFC TO 10,000FT F. 41,000 TO 45,000FT

FLIGHT FIVE -- TEAL 75

A. 01/1130Z

B. AFXXX 0711A JOAQUIN

C. 01/0730Z

D. 26.1N 73.7W

E. 01/1100Z TO 01/1400Z

F. SFC TO 10,000FT

[metagraphica]

....By tomorrow evening or so, I bet we have a MH on our hands....

 

Pretty impressive strengthening despite the shear today.  If the shear relaxes further this definitely could become an MH.

[LakeEffectKing]

Pretty impressive strengthening despite the shear today.  If the shear relaxes further this definitely could become an MH.

I think I see evidence of the shear decreasing as we speak...and it will do so further throughout tonight into tomorrow....this has a very nice circular structure in place....get the levels all lined up and this thing goes BAM!

[Windspeed]

One of the drastic changes in this system will be watching the reversal of flow at the 250 mb level. Most of the globals show 100kt+ flow bending sharply around the trough to the NW and then rapidly off to the NE away from the tilt. The evolution of that flow with respect to the position of Joaquin could create a significantly amped outflow channel that enhances the hurricane. Of course, position and timing are key. If that flow bends too far east, Joaquin gets blown to bits from the south. If it remains NW of Joaquin, especially if the mid-level steering is captured by the trough, this could get intense. I'm not sure if that is why the HWRF wants to bomb this into an intense hurricane, but it's clearly showing that possible channel in its own upper dynamics.

[Ground Scouring]

Once the low-level and mid-level centers become fully aligned, I truly believe that Joaquin will likely intensify faster than forecast. By days two and three, the storm will be wedged between a developing cutoff low over the Southeast and a cold mid-level trough over ex-Ida to its east. Such an environment is not only conditionally unstable, favoring rapid convective growth, but also, with a blocking high to the north, conducive to low ambient pressures as well as upper-level divergence.

This environment, filled with ample low-level moisture and high precipitable water, would support the development of dual outflow channels in the south and north quadrants of Joaquin, especially as the cutoff low becomes negatively tilted by day four and beyond. As Joaquin interacts with the trough, it may maintain its intensity or deepen even further on day four, thanks to some indirect baroclinic influences, as the storm initially parallels the mean shear vector.

Already, Joaquin is clearly organizing even though the centers are not yet fully aligned. The storm is clearly intensifying faster than originally expected, and even the deterministic ECMWF is likely underestimating the rate of deepening, showing 990 mb by 12Z tomorrow, even though the pressure is already down to that level. An excellent outflow channel is already established in the southern quadrant, and the nascent CDO is slowly expanding westward as northerly shear lessens.

Based on all indications, significant, quite possibly rapid intensification will commence tomorrow, as an upper-level anticyclone builds over the system. Thus, Joaquin will likely have about four full days (Wednesday through Saturday) to intensify significantly. The stronger intensity in the short term would likely bring the cyclone into the east-central Bahamas in little more than two days, with the deeper system enhancing mid-level heights to its north. The ECMWF ensembles have consistently shown this.

Given all indications and trends, I would not be surprised if Joaquin becomes a significant hurricane (85+ kt) as it meanders over the east-central Bahamas on Thursday and Friday. A potentially severe impact to the Bahamas (Eleuthera, Cat Island, San Salvador, and possibly even the Exumas) is becoming more plausible. The 1929 Bahamas hurricane underwent rapid deepening in a similar set-up; Joaquin may well follow its example, only farther east.

 

[Superstorm93]

I can garuntee the 18z HWRF will be the strongest run yet with the new intensity input. Even the LGEM brings it to a major hurricane now.

It's a shame we won't have recon at all tonight. In any case, this will more than likely be a hurricane by the time we have obs in tomorrow morning.

 

Sent from my SM-G925V

[bdgwx]

18Z NAM initialized at 992'ish. It's pretty close to the domain boundary though.

[bdgwx]

One of the drastic changes in this system will be watching the reversal of flow at the 250 mb level. Most of the globals show 100kt+ flow bending sharply around the trough to the NW and then rapidly off to the NE away from the tilt. The evolution of that flow with respect to the position of Joaquin could create a significantly amped outflow channel that enhances the hurricane. Of course, position and timing are key. If that flow bends too far east, Joaquin gets blown to bits from the south. If it remains NW of Joaquin, especially if the mid-level steering is captured by the trough, this could get intense. I'm not sure if that is why the HWRF wants to bomb this into an intense hurricane, but it's clearly showing that possible channel in its own upper dynamics.

 

Definitely something to watch for. And yes, I think that is at part of why the HWRF bombs the low. The UL dynamics are quite potent. A back building jet streak acquiring anti-cyclonic curvature and capturing the low in the right entrance region is pretty close to textbox. But, will it actually happen like that?

[Ground Scouring]

Josh should seriously consider flying to Nassau and then to the outer islands for this one...

 

Latest recon data suggest that winds are likely 55-60 kt. Edit: ATCF has 55 kt for the 18Z fix.

[Superstorm93]

Purely for entertainment purposes..

 

[huronicane]

From the sites in the red polygon, we'll have soundings at 0z tonight, 12z tomorrow, and every 6 hours after that.

[Windspeed]

Even though the 18z GFS wasn't initialized with the organizational improvements of Joaquin from the past six hours, the model has drastically evolved the cyclone compared to the 12z run. The 00z run should hopefully have an even better handle on things.

 

EDIT: I should also mention it captures the storm. Removed image since klw posted the same in the next post.

[klw]

18 Z GFS definitely will start the hype machine!  Isabel redux?

 

 

[Windspeed]

18 Z GFS definitely will start the hype machine!  Isabel redux?

 

 

 

This GFS run is a much different setup than what occurred with Isabel. Though we do have a blocking ridge over Nova Scotia, we also have a trough that is negatively tilting, capturing a hurricane that's moving N-NNE, pulling it back west and phasing it over the Mid-Atlantic states. Isabel, on the other hand, moved around the periphery the strong blocking high pressure and was driven NW all the way into the Great Lakes region. Isabel didn't stick around very long. This GFS solution would present a major flooding problem for the Mid-Atlantic. But again, it's just one model run...

[wxmx]

Now it appears the Euro is the outlier.

[bdgwx]

18Z GFS initialized at about 1000mb'ish. Interestingly this morning's 12Z FIM run was diverging quite a bit from the 12Z GFS past 72 hours. It showed the Sandy style left hook with a more intense low making landfall in Delaware.

[IsentropicLift]

18z HWRF 115MPH by hr 60.

[bobbutts]

Seems like a tough call for forecasters!  Ranging from huge impact like HWRF with a small hurricane towards Chesapeake Bay or Canadian up the Mid Atlantic into NYC to whiff on the Euro and others.  Clear trend for today seems to be higher intensity forecasts.

[Ground Scouring]

I think that the models have yet to come to terms with the short-term movement of Joaquin. The GFS has been much less reliable than the ECMWF ensembles in gauging the more southwesterly movement of Joaquin over the past 24 hours. The GFS was inconsistent and, until the past run, showed no sustained south-of-west motion before the turn to the north. Conversely, the ECMWF ensemble mean has shown this for more than a day, and has a done a better job with Joaquin's stronger-than-anticipated status.

This has key implications for the long-term track of Joaquin, for its position in two to three days will affect how it interacts with the cutoff low over the Southeast. The ECMWF ensemble mean is almost ~2 degrees south of the GFS solution by 12Z Thursday. A deeper and more southerly Joaquin, as seems more plausible, would more likely turn sharply northeast and miss a potential phasing with the trough as it acquires a negative tilt by days four and five.

 

Being near the trough axis rather than upstream, Joaquin would not turn significantly west of north by day five. A well-known meteorologist on Twitter likened the scenario to a person (the trough axis) kicking a football (Joaquin). By 120 hours, the blocking heights to its northeast will start to flatten, allowing the cyclone to curve just offshore of the Mid-Atlantic and southern New England. This scenario seems more likely than a Sandy-like phase over the Mid-Atlantic.

 

Needless to say, I'm far from being sold the deterministic GFS solution, especially since a hurricane striking the Mid-Atlantic or New England in a strong El Niño year would be unprecedented.

[Derecho!]

Now it appears the Euro is the outlier.

Euro is an outlier to its own ensembles. actually, the 18Z GFS is consistent with the most common EC and GFS ensemble members from 12z and earlier runs.

[Windspeed]

I think that the models have yet to come to terms with the short-term movement of Joaquin. The GFS has been much less reliable than the ECMWF ensembles in gauging the more southwesterly movement of Joaquin over the past 24 hours. The GFS was inconsistent and, until the past run, showed no sustained south-of-west motion before the turn to the north. Conversely, the ECMWF ensemble mean has shown this for more than a day, and has a done a better job with Joaquin's stronger-than-anticipated status.

This has key implications for the long-term track of Joaquin, for its position in two to three days will affect how it interacts with the cutoff low over the Southeast. The ECMWF ensemble mean is almost ~2 degrees south of the GFS solution by 12Z Thursday. A deeper and more southerly Joaquin, as seems more plausible, would more likely turn sharply northeast and miss a potential phasing with the trough as it acquires a negative tilt by days four and five.

 

Being near the trough axis rather than upstream, Joaquin would not turn significantly west of north by day five. A well-known meteorologist on Twitter likened the scenario to a person (the trough axis) kicking a football (Joaquin). By 120 hours, the blocking heights to its northeast will start to flatten, allowing the cyclone to curve just offshore of the Mid-Atlantic and southern New England. This scenario seems more likely than a Sandy-like phase over the Mid-Atlantic.

 

Needless to say, I'm far from being sold the deterministic GFS solution, especially since a hurricane striking the Mid-Atlantic or New England in a strong El Niño year would be unprecedented.

 

I agree and I also think this is why the 00z runs of the global models will begin to show far less spread versus the 12z. A hurricane that deepens faster than any of the models anticipated could have significant effects downstream in overall position, eventual interaction and capture (if at all) with the trough in this pattern. The intensity trends, position and data from this afternoon and evening are supposed to be initialized in the 00z run. If the Euro still ejects this system out towards Bermuda as a hurricane, then I will have a much harder time believing in a phase-type event. I would almost expect some of the other models, including the GFS to shift east, with that same information being incorporated. But, on the other hand, if the Euro shifts west and the GFS, UKMet and the GEM remain close to the coast, continue to hint at phase or closer interaction with the trough, then obviously concern will grow in a great order of magnitude.

[Ground Scouring]

The convective pattern of Joaquin suggests that the center may begin moving almost due south or west-southwest over the next 12 hours. The developing inflow band on the south and west sides will likely pull the center southward as convection strengthens, further enabling steady intensification. Rapid deepening will likely begin in earnest late tomorrow as the internal structure improves. I'm thinking that 90-95 kt by late Thursday seems very plausible, and I would not rule out 100-105 kt. A significant impact to San Salvador and Eleuthera is increasingly likely.

 

[Superstorm93]

Proto-eye forming 

 

[OHweather]

Proto-eye forming

I think that's a hot tower/overshooting top as it appeared in the middle of a very robust burst of convection. Either way, man, this looks ready to go to town within the next 12-24 hours as shear continues to relax.

[Superstorm93]

AL, 11, 2015093000, , BEST, 0, 258N, 715W, 60, 988, TS

[Derecho!]

18z GEFS ensemble members now much more consistent with each other in a strong storm into the mid-Atlantic in almost all, but timing varies a bit.

[Ground Scouring]

Comparison between the 00Z and 12Z ECMWF ensembles shows more spread among the individual members and less of a phase within the 12Z guidance. The 12Z suite also shows less of a sharp northwest bend with many members, with more showing a general north movement off the East Coast than at 00Z. So there is a definite eastward trend within the widening spread/uncertainty, further supporting my contention that a more southerly/deeper storm within the short term would more likely miss the East Coast.

[Minnesota Meso]

Using the known bias's of the ECMWF and the GFS based on their 09/29/12z runs.  The GFS is to fast advancing the eastern trough  thus tossing Joaquin more or less out to sea, with some heavy rains over the east coast, as a strong coastal low sets up..  At the same time the ECMWF may be holding the trough to far back and not picking up Joaquin soon enough.

 

I'm not going to post the images of the 09/29/18z run of the GFS as most of you know how to find it, but it appears that it has made the adjustment.  However it looks like a good compromise to me. Time to wait to see what the 09/30/0z runs will show.

[OHweather]

Comparison between the 00Z and 12Z ECMWF ensembles shows more spread among the individual members and less of a phase within the 12Z guidance. The 12Z suite also shows less of a sharp northwest bend with many members, with more showing a general north movement off the East Coast than at 00Z. So there is a definite eastward trend within the widening spread/uncertainty, further supporting my contention that a more southerly/deeper storm within the short term would more likely miss the East Coast.

It's interesting that the GFS went from a weak Joaquin that opens up into a trough in a few days to a much more robust system and went from taking the scraps of Joaquin OTS to taking a strong cyclone into the Mid-Atlantic. 18z GEFS also trended left overall.

[Jim Marusak]

looking at this storm in a broader sense, what's the meaning of that stream of t-storms going from the SW outflow of the storm to Salisbury, MD (sby)? is that maybe a 2nd outflow channel? or maybe a link between Joaquin and jet stream to the west that could maybe be the path where he eventually goes?