EPAC: EUGENE - Post-Tropical

[TropicalAnalystwx13]

Dry air is causing the system quite a bit of trouble this evening. The earlier RI has definitely leveled off, and it appears Eugene is holding steady at 65-70kt.

[Kingarabian]

3 hours ago:



Recent infrared imagery show the western eyewall is now stronger than eastern side though.

[hurricanes1234]

Unfortunately I'm starting to think this may not have enough time to strengthen beyond a Category 1.

[Kingarabian]

Unfortunately I'm starting to think this may not have enough time to strengthen beyond a Category 1.

It has 24 more hours. GFS doesn't peak it until 12 hours from now.

[Kingarabian]

09/0000 UTC 14.1N 113.3W T4.5/4.5 EUGENE -- East Pacific

TXPZ28 KNES 090032
TCSENP

A. 05E (EUGENE)

B. 09/0000Z

C. 14.1N

D. 113.3W

E. ONE/GOES-W

F. T4.5/4.5/D2.5/24HRS

G. IR/EIR/VIS

H. REMARKS...MG EYE IS SURROUNDED BY LG AND EMBEDDED IN LG WHICH RESULTS
IN A DT=4.5 AFTER 0.5 IS SUBTRACTED FOR AN EYE ADJ. PT=4.0. MET=3.5
BASED ON RAPID DEVELOPMENT OVER THE LAST 24 HOURS. FT IS BASED ON DT.

I. ADDL POSITIONS

NIL


...SANDUSKY

[Kingarabian]

Intensifying again. EUGENE YOU CAN DO IT KEEP GOING!

[Kingarabian]

[Yellow Evan]

EP, 05, 2017070900, , BEST, 0, 141N, 1133W, 65, 991, HU, 64, NEQ, 20, 0, 0, 0, 1012, 180, 20, 0, 0, E, 0, , 0, 0, EUGENE, D, 0, , 0, 0, 0, 0, genesis-num, 008,

[Kingarabian]

EP, 05, 2017070900, , BEST, 0, 141N, 1133W, 65, 991, HU, 64, NEQ, 20, 0, 0, 0, 1012, 180, 20, 0, 0, E, 0, , 0, 0, EUGENE, D, 0, , 0, 0, 0, 0, genesis-num, 008,

Way too low considering its MW presentation. ADT is almost @ 4.5, which would be 75kts at least.

[hurricanes1234]

Personally I don't think they'll go with above 65 knots. If anything, maybe 70 but not 75.

Now I agree that it does have the look of a 75 knot system to my amateur eyes.

[SouthDadeFish]

I haven't seen anything to show the intensification trend has leveled off... The vigorous convective bursts in the eyewall are obscuring the eye on conventional geostationary satellite imagery. On microwave imagery you can see a clearly defined eyewall and eye. This TC has a legit shot of reaching major status, in my opinion.

[Yellow Evan]

Personally I don't think they'll go with above 65 knots. If anything, maybe 70 but not 75.

Given SAB is at T4.5 along with ADT, that easily justifies 70.

[Kingarabian]

ADT would be a lot higher if it could get the center right...

[cycloneye]

Forecast to be a cat 2.

Hurricane Eugene Discussion Number 6
NWS National Hurricane Center Miami FL EP052017
900 PM MDT Sat Jul 08 2017

Eugene has strengthened rapidly over the past 24 h and has reached
hurricane strength during the past few hours. Recent microwave
imagery indicates that a 25 n mi wide eye has formed, and this
feature has also appeared sporadically in visible and infrared
imagery. The initial intensity is raised to 70 kt based on various
satellite intensity estimates in the 65-75 kt range. The hurricane
continues to have good to excellent cirrus outflow in all directions
as it remains in an environment of light vertical wind shear.

Smoothing through the wobbles of the formative eye, the initial
motion is 320/7. The hurricane is moving toward a weakness in the
subtropical ridge to the west of the Baja California Peninsula, and
the track forecast guidance is in good agreement that a
northwestward motion should continue through the forecast period,
with some increase in forward speed during the first 24 h and some
decrease in forward speed after 72 h. The guidance has changed
little since the last advisory, and the new forecast track is
similar to the previous forecast.

Eugene should remain over warm water and in a light shear
environment for about the next 24 h. Thus, additional strengthening
is expected, with the main question being will the current rate of
intensification continue. The forecast peak intensity is increased
to 90 kt, which is above the intensity guidance but could be
conservative if the intensification rate does not decrease. After
24 hours, the cyclone should move over colder water, with the sea
surface temperature along the forecast track expected to be near
21C by 96 h. This should cause Eugene to steadily or rapidly weaken
after 24 h, with the system expected to decay to a remnant low by 96
h.


FORECAST POSITIONS AND MAX WINDS

INIT 09/0300Z 14.4N 113.5W 70 KT 80 MPH
12H 09/1200Z 15.4N 114.3W 80 KT 90 MPH
24H 10/0000Z 16.9N 115.6W 90 KT 105 MPH
36H 10/1200Z 18.7N 117.1W 80 KT 90 MPH
48H 11/0000Z 20.2N 118.4W 65 KT 75 MPH
72H 12/0000Z 22.5N 120.5W 40 KT 45 MPH
96H 13/0000Z 24.5N 122.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 14/0000Z 26.0N 124.5W 20 KT 25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Beven

[TropicalAnalystwx13]

Agree with NHC's 70kt. Cloud pattern has become more symmetric over the past few hours, though it's obvious there's dry air lurking outside the CDO and across the eastern semicircle of the cyclone. If the convective blow-up in the western eyewall wraps around and isn't disrupted, there's no reason Eugene won't reach Cat 2 intensity tomorrow.

[Kingarabian]

Could be a major hurricane by the next advisory. Only question is if Satellite intensity forecasts will keep up.

[Kingarabian]

SouthDadeFish
is absolutely right.

The overshooting cloud tops are obscuring the eye. Thus, Dvorak estimates are thrown off. We've seen this happen in Atlantic systems in the past that have recon. Overshooting cloud tops clouding the eye yet the storm having stronger winds despite the filled eye presence on satellite.

Check this recent 30 minute old GMI pass. Look how intense the eyewall is in almost all the quads.



That's clearly a strong eyewall, and Eugene is close if not already a major hurricane. Typically with EPAC storms we see an eyewall develop followed by an eye clearing out shortly after. The eyewall is clearly evident here and the eye is defined in microwave but no so much on visible.

[Yellow Evan]

Could be a major hurricane by the next advisory. Only question is if Satellite intensity forecasts will keep up.

It's convection is gonna really need to wrap around, and I don't see a thick B or W ring developing and persisting, or the eye getting 10C+ in the next few hours. In 12-18 hours? Sure.

[Kingarabian]

Could be a major hurricane by the next advisory. Only question is if Satellite intensity forecasts will keep up.

It's convection is gonna really need to wrap around, and I don't see a thick B or W ring developing and persisting, or the eye getting 10C+ in the next few hours. In 12-18 hours? Sure.

Eyewall is intense and eye is defined enough to indicate at Cat3 per microwave. Compare that GMI pass with past hurricanes and you'll see the comparison.

[1900hurricane]

I'm not sure how much the NHC trusts SATCON, but every single one of its recent components are higher than the 00Z best track update (no SSMIS updates in a while though). As of now, the SATCON mean is at 78 kt.