CPAC: LANE - Post-Tropical

[supercane4867]

I thought the title of this thread was a mistake - Lane TS?? I do not understand the reasoning for an upgrade. It's a swirl of low clouds devoid of any convection. No inflow. I'm speechless...

Did you ever look the satellite loop? CPHC upgraded it earlier today when the center was clearly under or near the convection.

It was probably a TS at the time, but I agree it will be downgraded again very soon.

[wxman57]

I thought the title of this thread was a mistake - Lane TS?? I do not understand the reasoning for an upgrade. It's a swirl of low clouds devoid of any convection. No inflow. I'm speechless...

Did you ever look the satellite loop? CPHC upgraded it earlier today when the center was clearly under or near the convection.

It was probably a TS at the time, but I agree it will be downgraded again very soon.


https://i.imgur.com/jcLCAlu.gif

I would disagree that a temporary squall NE of the center = TS intensity. There was no inflow. ScatSat had 25 kts in that convection. Definitely a remnant low now. I'll be curious what CPHC does this hour.

[1900hurricane]

I'm surprised to see CPHC reference SATCON in their most recent discussion. I love using SATCON as an intensity guidance tool for intense systems, but as far as I can tell, it kind of sucks for weak systems.

[somethingfunny]

Has the rain ended in Hawaii yet? At what point would rainfall be attributed to standard trade wind showers rather than included in Lane's storm totals?

[cycloneye]

Tropical Storm Lane Discussion Number 54
NWS Central Pacific Hurricane Center Honolulu HI EP142018
1100 AM HST Mon Aug 27 2018

Visible imagery from Himawari continues to show an exposed low
level circulation center with the cold, high clouds shearing off
farther to the northest. Over the past several hours the amount of
cold, high clouds has decreased in area and the tops have
warmed. Subjective Dvorak intensity estimates from HFO, SAB
and JTWC were all 2.0/30 kt. The initial intensity for this
advisory has been kept at 35 kt, but that may be generous.

A strong east northeast to west southwest ridge north of Lane
continues to steer the storm. The initial motion for this advisory
is 260/6 kt. Satellite water vapor loops show a deep low aloft near
24N 172W. Southwest flow associated with this low is producing the
shear now impacting Lane. The low aloft is forecast to deepen a
north south surface trough along 170W. The weakening circulation of
Lane will become part of this trough and turn toward the north
northwest tonight.

Lane is forecast to weaken to a post-tropical remnant low within 24
hours. The remnant low will continue to weaken as a new
extratropical low forms to the northwest. The remnants of Lane will
become wrapped up into that low.


FORECAST POSITIONS AND MAX WINDS

INIT 27/2100Z 18.4N 166.4W 35 KT 40 MPH
12H 28/0600Z 18.9N 167.1W 30 KT 35 MPH
24H 28/1800Z 20.0N 168.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
36H 29/0600Z 21.6N 169.1W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 29/1800Z 23.5N 170.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 30/1800Z...DISSIPATED

$$
Forecaster Donaldson

[TheAustinMan]

Pending a review of the data, the reporting station at Mountain View would suggest that Lane has broken the Hawaiian rainfall record long held by Hurricane Hiki in 1950. The Mountain View station reported a storm total of 52.02", which beats Hiki by just two hundredths of an inch. An unofficial private station recorded 58.50", but that too will need to be verified. The preliminary would also indicate that Lane has taken a spot in second place for the highest tropical cyclone rainfall maximum in United States history.

Public Information Statement
National Weather Service Honolulu HI
305 PM HST Mon Aug 27 2018

...LANE POSSIBLY BREAKS HAWAII TROPICAL CYCLONE RAINFALL
RECORD...

The Mountain View gage has measured 52.02 inches of rain for the
period from 8 AM HST August 22 when the outer rain bands started
impacting the Big Island through 8 AM HST August 26 after the
trailing rain band passed west of South Point. An unverified
private weather station also reported 58.80 inches during this
same time span. We will attempt to validate this private weather
station report. Both totals indicate that Hurricane Lane has
broken the Hawaii tropical cyclone storm total rainfall record,
pending verification of the data. The previous record was 52.00
inches, measured at Kanalohuluhulu Ranger Station, during
Hurricane Hiki in 1950. The Hurricane Lane total would also make
it the second highest storm total rainfall from a tropical cyclone
in the United States since 1950. The highest total is 60.58
inches, measured at Nederland, Texas, during Hurricane Harvey in
2017.

Here are some of the notable rainfall totals from the ongoing
event, covering the period from 8 AM HST August 22 through 8 AM
HST August 26. All values are in inches, and are preliminary
pending final quality control.

Island of Hawaii
Mountain View : 52.02
Waiakea Uka : 49.48
Saddle Quarry (USGS) : 48.52
Piihonua : 48.13
Waiakea Experiment Station : 47.37
Pahoa : 38.09
Glenwood : 35.83
Kulani NWR : 28.71
Keaumo : 24.65
Kawainui Stream (USGS) : 16.70
Puu Mali : 13.70

Island of Maui
West Wailuaiki (USGS) : 25.58
Puu Kukui (USGS) : 17.48
Hana Airport : 10.57
Haiku : 10.55

[TheStormExpert]

With Lane being now likely the 2nd wettest TC in the U.S. (behind Harvey) I'd be shocked if it doesn't get retired next spring.

 https://twitter.com/MichaelRLowry/status/1034271884827930624

[cycloneye]

Tropical Depression Lane Discussion Number 55
NWS Central Pacific Hurricane Center Honolulu HI EP142018
500 PM HST Mon Aug 27 2018

Visible imagery from Himawari continues to show an exposed low
level circulation center. The closest cold, high clouds associated
with Lane are over 90 nm northeast of the center. Subjective Dvorak
intensity estimates from HFO, SAB and JTWC were all 2.0/30 kt. The
initial intensity for this advisory has been lowered to 30 kt, and
Lane has been downgraded to a depression.

A strong east northeast to west southwest ridge north of Lane
has continued to steer the storm toward the west. The initial motion
for this advisory is 270/6 kt. Satellite water vapor loops show a
deep low aloft near 23N 172W. Southwest flow associated with this
low is producing strong southwest vertical wind shear over Lane. The
UM-CIMSS shear estimate was 51.2 kt. The low aloft is forecast to
induce a deepening north south surface trough along 170W. The
weakening circulation of Lane will become part of this trough and
turn toward the north northwest tonight.

Lane is forecast to weaken to a post-tropical remnant low within 24
hours. The remnant low will continue to weaken as a new
extratropical low forms to the northwest. The remnants of Lane will
become wrapped up into that low.


FORECAST POSITIONS AND MAX WINDS

INIT 28/0300Z 18.5N 166.6W 30 KT 35 MPH
12H 28/1200Z 18.8N 167.5W 25 KT 30 MPH
24H 29/0000Z 19.5N 168.2W 25 KT 30 MPH...POST-TROP/REMNT LOW
36H 29/1200Z 20.9N 168.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 30/0000Z 22.0N 168.8W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 31/0000Z...DISSIPATED

$$
Forecaster Donaldson

[HurricaneRyan]

With Lane being now likely the 2nd wettest TC in the U.S. (behind Harvey) I'd be shocked if it doesn't get retired next spring.

 https://twitter.com/MichaelRLowry/status/1034271884827930624

Has the rainfall been that bad though? Aside from the rainfall we haven't heard much on destruction

[cycloneye]

Tropical Depression Lane Discussion Number 57
NWS Central Pacific Hurricane Center Honolulu HI EP142018
500 AM HST Tue Aug 28 2018

Overnight GOES-15 fog product imagery along with a few VIIRS
images and a Monday evening SCATSAT pass show that the exposed low
level circulation center (LLCC) of Lane has started tracking
to the west-northwest, and has become increasingly elongated and
indistinct during the night. However, for the third night in a
row, despite very strong vertical wind shear estimated at 57 kt by
CIMSS, Lane managed to produce a substantial and persistent burst of
deep convection just to the northeast of the LLCC, which kept the
system classifiable for this cycle. Subjective Dvorak current
intensity estimates came in at 1.5/25 kt from HFO and SAB, and
2.0/30 kt from JTWC, and the latest CIMSS ADT has increased to
1.9/29 kt in response to the deep convection NE of the center. The
overnight ASCAT pass sampled only the eastern part of Lane's
circulation, but did find a small area of 30 kt winds there. We have
therefore maintained Lane as a 30 kt tropical depression for this
advisory.

With the anticipated turn toward the northwest now apparently
underway, the initial motion for this advisory is set at 290/9 kt.
Lane is now beginning to feel the influence of a strong low aloft
which water vapor imagery shows centered near 22N 172W. Model
guidance continues to show Lane being picked up by a developing
low-level trough induced by the upper trough, with the depression
expected to turn NW then NNW later today. The new forecast track is
very similar to the previous track, and remains on the left side of
the guidance envelope in best agreement with the ECMWF.

Very strong shear is forecast to continue along the forecast track
of Lane during the next couple of days. The new intensity forecast
anticipates that Lane will become a remnant low later today as
the LLCC continues to become less organized, and the current deep
convection will likely wane as it has during the past couple of
daytime periods. The remnant low will then be absorbed within 36
hours into a larger extratropical low forecast to develop farther to
the north.


FORECAST POSITIONS AND MAX WINDS

INIT 28/1500Z 18.8N 168.5W 30 KT 35 MPH
12H 29/0000Z 20.0N 169.2W 25 KT 30 MPH...POST-TROP/REMNT LOW
24H 29/1200Z 21.8N 169.7W 25 KT 30 MPH...POST-TROP/REMNT LOW
36H 30/0000Z...DISSIPATED

$$
Forecaster Jacobson

[Kingarabian]

Ryan Maue thinks that Lane's rainfall totals are bogus:

 https://twitter.com/RyanMaue/status/1034482301453971458

[1900hurricane]

I guess he's referencing 95C?

[wx98]

Maue seems to have lost his cool on that one. I’m not too sure that was a developed tropical system as much as it was just an outer part of Lane, but...

[cycloneye]

Post-Tropical Cyclone Lane Discussion Number 59
NWS Central Pacific Hurricane Center Honolulu HI EP142018
500 PM HST Tue Aug 28 2018

Visible imagery shows the low level center has become elongated
from northeast to southwest and less tightly wound. Since 2 PM,
some low clouds near the center have dissipated, making the center
hard to locate very precisely. The cold, high clouds northeast of
the center have continued to warm, decrease in area and drift
farther from the center. Subjective Dvorak estimates from HFO and
SAB were 1.5/25 kt. JTWC called the system too weak to classify. The
latest CIMSS ADT was 1.5/25 kt. Lane is now a post-tropical remnant
low. This will be our last set of advisories on the system.

Our forecast reasoning remains the same. The circulation around a
low aloft near 21N 171W continues to produce strong southwest
vertical wind shear over Lane. The CIMSS estimate at 0000 UTC was
47.5 kt over Lane. With convection shearing off to the northeast,
the remnant low will continue to weaken. A north-south low-level
trough is deepening near 170W and the global models remain in good
agreement showing a new extratropical surface low forming within the
trough tonight near 30N 170W.

Lane is forecast to move north this evening, then curve slightly
toward the north northwest. That motion is expected to continue
until whatever might be left of Lane is absorbed into the
extratropical low developing to the north.


FORECAST POSITIONS AND MAX WINDS

INIT 29/0300Z 19.5N 168.3W 25 KT 30 MPH...POST-TROPICAL
12H 29/1200Z 21.0N 168.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
24H 30/0000Z 23.0N 169.0W 20 KT 25 MPH...POST-TROP/REMNT LOW
36H 30/1200Z...POST-TROP/REMNT LOW

$$
Forecaster Donaldson

[DioBrando]

NOO!
DON'T GO MY LOVE!

[Kingarabian]

Goodbye Lane. One of my most memorable storms. Taught me a lot, and most importantly it taught me to take TC threats very seriously.

[CrazyC83]

I'm leaning against retirement. Most of the incredible totals were in remote areas, not near the population centers, and it doesn't appear to have been even as bad as Iselle otherwise.

[CrazyC83]

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the National Hurricane Center and National Weather Service.

As for what I would have as Lane's best track, here is what I would set it (starting at initial circulation):

EP142018, LANE, 77,
20180814, 0000, , LO, 11.1N, 116.5W, 25, 1013,
20180814, 0600, , LO, 11.0N, 117.3W, 25, 1013,
20180814, 1200, , LO, 11.0N, 118.2W, 25, 1012,
20180814, 1800, , LO, 11.0N, 119.4W, 25, 1012,
20180815, 0000, , TD, 10.9N, 120.6W, 30, 1010,
20180815, 0600, , TS, 10.8N, 121.7W, 35, 1008,
20180815, 1200, , TS, 10.7N, 122.8W, 35, 1008,
20180815, 1800, , TS, 10.5N, 123.9W, 45, 1005,
20180816, 0000, , TS, 10.3N, 124.9W, 45, 1006,
20180816, 0600, , TS, 10.3N, 125.9W, 45, 1006,
20180816, 1200, , TS, 10.4N, 126.9W, 50, 1003,
20180816, 1800, , TS, 10.5N, 127.9W, 60, 1001,
20180817, 0000, , HU, 10.9N, 129.2W, 65, 998,
20180817, 0600, , HU, 11.1N, 130.7W, 75, 992,
20180817, 1200, , HU, 11.2N, 132.1W, 80, 988,
20180817, 1800, , HU, 11.3N, 133.6W, 90, 981,
20180818, 0000, , HU, 11.6N, 134.9W, 105, 968,
20180818, 0600, , HU, 11.9N, 136.2W, 120, 957,
20180818, 1200, , HU, 12.1N, 137.5W, 125, 951,
20180818, 1800, , HU, 12.4N, 138.9W, 120, 955,
20180819, 0000, , HU, 12.6N, 140.3W, 110, 963,
20180819, 0600, , HU, 12.8N, 141.6W, 105, 966,
20180819, 1200, , HU, 13.1N, 142.9W, 100, 970,
20180819, 1800, , HU, 13.4N, 144.1W, 105, 967,
20180820, 0000, , HU, 13.6N, 145.3W, 105, 966,
20180820, 0600, , HU, 13.7N, 146.5W, 105, 966,
20180820, 1200, , HU, 13.7N, 147.7W, 110, 965,
20180820, 1800, , HU, 13.7N, 148.6W, 110, 964,
20180821, 0000, , HU, 13.8N, 149.8W, 120, 957,
20180821, 0600, , HU, 13.9N, 150.8W, 125, 952,
20180821, 1200, , HU, 14.0N, 151.8W, 135, 945,
20180821, 1800, , HU, 14.2N, 152.7W, 140, 941,
20180822, 0000, , HU, 14.4N, 153.6W, 145, 930,
20180822, 0600, , HU, 14.5N, 154.2W, 145, 926,
20180822, 1200, , HU, 14.9N, 155.0W, 135, 938,
20180822, 1800, , HU, 15.2N, 155.6W, 130, 940,
20180823, 0000, , HU, 15.6N, 156.3W, 120, 946,
20180823, 0600, , HU, 16.0N, 156.7W, 125, 942,
20180823, 1200, , HU, 16.6N, 157.2W, 115, 949,
20180823, 1800, , HU, 17.0N, 157.5W, 105, 954,
20180824, 0000, , HU, 17.5N, 157.8W, 100, 956,
20180824, 0600, , HU, 18.0N, 157.9W, 95, 961,
20180824, 1200, , HU, 18.4N, 157.9W, 85, 968,
20180824, 1800, , HU, 18.8N, 158.0W, 70, 977,
20180825, 0000, , TS, 19.1N, 158.1W, 55, 988,
20180825, 0600, , TS, 19.3N, 158.2W, 50, 992,
20180825, 1200, , TS, 19.5N, 158.6W, 45, 995,
20180825, 1800, , TS, 19.6N, 159.1W, 45, 996,
20180826, 0000, , TS, 19.5N, 160.0W, 40, 999,
20180826, 0600, , TS, 19.4N, 160.7W, 40, 1000,
20180826, 1200, , TS, 19.3N, 161.6W, 35, 1003,
20180826, 1800, , TS, 19.2N, 162.4W, 35, 1003,
20180827, 0000, , TS, 19.0N, 163.3W, 35, 1004,
20180827, 0600, , TS, 18.9N, 164.3W, 35, 1004,
20180827, 1200, , TS, 18.8N, 165.1W, 40, 1002,
20180827, 1800, , TS, 18.6N, 166.0W, 40, 1003,
20180828, 0000, , TS, 18.4N, 166.5W, 35, 1005,
20180828, 0600, , TD, 18.5N, 167.1W, 30, 1008,
20180828, 1200, , LO, 18.6N, 168.1W, 30, 1008,
20180828, 1800, , LO, 18.7N, 168.5W, 25, 1010,
20180829, 0000, , LO, 19.1N, 169.0W, 25, 1011,
20180829, 0600, , LO, 19.7N, 169.2W, 25, 1011,
20180829, 1200, , LO, 20.9N, 169.3W, 25, 1010,
20180829, 1800, , LO, 22.9N, 169.8W, 25, 1010,
20180830, 0000, , LO, 24.5N, 171.0W, 30, 1008,
20180830, 0600, , LO, 26.3N, 171.5W, 30, 1007,
20180830, 1200, , LO, 28.4N, 172.8W, 35, 1004,
20180830, 1800, , LO, 30.2N, 174.2W, 40, 1003,
20180831, 0000, , SS, 30.5N, 175.5W, 45, 1001,
20180831, 0600, , SS, 31.3N, 176.4W, 45, 1000,
20180831, 1200, , SS, 31.8N, 177.1W, 50, 998,
20180831, 1800, , SS, 32.2N, 177.5W, 50, 998,
20180901, 0000, , SS, 32.7N, 177.8W, 50, 997,
20180901, 0600, , SS, 33.5N, 178.0W, 55, 995,
20180901, 1200, , TS, 34.4N, 178.2W, 55, 994,
20180901, 1800, , TS, 35.6N, 178.4W, 60, 992,
20180902, 0000, , TS, 36.8N, 178.5W, 60, 990,
20180902, 0600, , HU, 38.0N, 178.5W, 65, 986,

* The EPAC portion is largely unchanged, although an initial peak of 125 kt is added when satellite was best at that point.
* After the reorganization, the peak intensity is increased to 145 kt.
* From the peak until after rapid weakening, the intensities are mostly brought down. That is especially true on the 24th.
* Based on ASCAT passes, the intensities after Hawaii are increased - I believe it remained a TS in that time.
* UPDATE September 1: Designated the unnamed storm mentioned by some as an extension of Lane.

[Kingarabian]

 https://twitter.com/bodyboarder22/status/1035177669543874561

[NotoSans]

ASCAT data showed that LANE has maintained a well-defined circulation with maximum sustained winds of around 45 knots to the east of its center. Looking at the convective structure at satellite imagery, I think it may be classified as a subtropical storm.