EPAC: HILDA- Post-Tropical

[Yellow Evan]

0z GFS has the lemon and 10E. It appers that after day 5-6 the ridge may re-build taking it closer to Hawaii. Not supported by the 12z ECMWF.

[Yellow Evan]

06/0600 UTC 12.5N 130.2W T2.0/2.0 10E -- East Pacific

[Yellow Evan]

EP, 10, 201508060600, 10, DVTS, CI, , 1250N, 13010W, , 3, 30, 2, 1009, 2, DVRK, , , , , , , , , , , , , , E, TAFB, MN, I, 5, 2020 /////, , , GOES15, CSC, T, WHITE TOPS ARE WARMING AT 06Z...THUS WENT WITH FT OF

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                    * EAST PACIFIC SHIPS INTENSITY FORECAST          *
                    * IR SAT DATA AVAILABLE,       OHC AVAILABLE     *
                    *  TEN         EP102015  08/06/15  06 UTC        *

TIME (HR)          0     6    12    18    24    36    48    60    72    84    96   108   120
V (KT) NO LAND    30    32    34    37    41    47    55    61    64    66    65    64    62
V (KT) LAND       30    32    34    37    41    47    55    61    64    66    65    64    62
V (KT) LGE mod    30    31    32    34    36    41    47    53    59    63    64    63    62
Storm Type      TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP

SHEAR (KT)         9     9     5     2     4     8     5     6     4     8     8    14    22
SHEAR ADJ (KT)    -1     0     0     1    -1     0     2     2     3     0    -2    -3    -3
SHEAR DIR         63    81    85    70    16    23    51    35   352   335   278   278   253
SST (C)         28.5  28.6  28.7  28.9  28.9  28.8  28.5  28.2  27.8  27.5  27.2  26.9  26.5
POT. INT. (KT)   150   150   151   153   153   152   149   146   142   138   134   131   127
200 MB T (C)   -51.4 -51.6 -51.8 -51.5 -51.6 -52.0 -51.9 -52.3 -52.2 -52.8 -52.5 -53.0 -53.0
TH_E DEV (C)       7     7     7     7     7     7     7     6     6     5     6     5     5
700-500 MB RH     67    69    70    68    68    68    67    64    60    60    60    62    63
MODEL VTX (KT)     8     9     9     9     9     9     9    10    10    12    12    13    14
850 MB ENV VOR    24    27    30    32    32    24    18    11    15    17    14     1     3
200 MB DIV        26    21    17    23    18    20    27    18    32    27    21    29    36
700-850 TADV      -1     0     0     0    -1    -2     0    -1     0     0     0     2     2
LAND (KM)       2331  2400  2471  2437  2339  2144  1953  1757  1529  1337  1179  1074  1014
LAT (DEG N)     12.5  12.5  12.5  12.6  12.6  12.7  13.2  13.8  14.7  15.5  16.2  17.2  18.5
LONG(DEG W)    130.3 131.3 132.2 133.2 134.1 136.0 137.7 139.4 141.3 142.9 144.2 144.9 145.2
STM SPEED (KT)    10     9     9     9     9     9     8    10     9     8     6     6     6
HEAT CONTENT      27    28    29    28    23    24    20    12    14    13    13    16    10

  FORECAST TRACK FROM OFCI

What shear? Very little until day 5. Dry air isn't as bad as I thought. Decent chance this reaches 55 knts or so.

[Kingarabian]

ECMWF continues the recurve.

[cycloneye]

TROPICAL DEPRESSION TEN-E DISCUSSION NUMBER 2
NWS NATIONAL HURRICANE CENTER MIAMI FL EP102015
200 AM PDT THU AUG 06 2015

Dry mid- to upper-level air from the south has wrapped into the
circulation and now surrounds the inner core, having completely cut
off and weakened the convective band in the northern semicircle.
However, a small concentration of deep convection has persisted
near and to the west of the well-defined low-level center as noted
in recent passive microwave satellite imagery. Dvorak satellite
intensity estimates are a consensus T2.0/30 kt from TAFB and SAB,
and a partial ASCAT-B overpass around 0552 UTC indicated 27-kt
surface winds in the convection just west of the center. Therefore,
the initial intensity remains at 30 kt for this advisory.

The motion continues to be 270/10 kt. The depression is forecast
to maintain a general westward motion for the next 48 hours or so,
followed by a turn toward the west-northwest by 72 hours as the
cyclone reaches the southwestern periphery of the deep-layer
subtropical ridge located to its north. Most of the 0000 UTC global
models, especially the GFS and ECMWF, have backed off somewhat on
developing a large break in the ridge to the northeast of the
Hawaiian Islands by days 4 and 5. This has resulted in a significant
westward and southward shift of the guidance envelope. The official
forecast track follows suit and has been shifted to the left of the
previous advisory track after 72 hours, but not nearly as far left
as the GFS-ECMWF model consensus. I would prefer to see a couple of
more model runs before making such a large shift in the forecast
track, in case this is a diurnal fluctuation for only one cycle.

The cyclone is expected to remain over warm waters of at least 28C
for the next 72 hours, and in a low-shear environment of 5-10 kt for
the next 96 hours. These favorable factors would normally result in
significant strengthening. Although proximity to the aforementioned
dry air will likely inhibit and disrupt the normal intensification
process, the cyclone is still forecast to achieve hurricane status
by day 4. Westerly vertical wind shear of at least 20 kt is expected
to impinge on the system by day 5, resulting in steady weakening.
The NHC intensity forecast is similar to the intensity consensus
model IVCN.

FORECAST POSITIONS AND MAX WINDS

INIT 06/0900Z 12.5N 130.8W 30 KT 35 MPH
12H 06/1800Z 12.6N 132.3W 35 KT 40 MPH
24H 07/0600Z 12.6N 134.3W 40 KT 45 MPH
36H 07/1800Z 12.9N 136.4W 45 KT 50 MPH
48H 08/0600Z 13.5N 138.4W 50 KT 60 MPH
72H 09/0600Z 14.7N 142.4W 60 KT 70 MPH
96H 10/0600Z 16.5N 145.6W 65 KT 75 MPH
120H 11/0600Z 18.3N 147.4W 55 KT 65 MPH

$$
Forecaster Stewart

[cycloneye]

TROPICAL STORM HILDA DISCUSSION NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL EP102015
800 AM PDT THU AUG 06 2015

The cyclone's cloud pattern has significantly increased in
organization since late yesterday. There is now a small central mass
of deep convection, with a band on the northern side of the
circulation. The center, according to an 1132 UTC SSM/I pass, is
also directly underneath this central convection, and the same pass
indicates increasing symmetry to the overall convective structure.
Satellite classifications from 1200 UTC were T2.0/30 kt and T2.5/35
kt from SAB and TAFB, respectively. The initial intensity estimate
is set at the higher end of these estimates (35 kt), based on the
even greater organization seen in satellite imagery since that time.

The initial motion is toward the west or 275/11. The general
forecast scenario is for a subtropical ridge north of the cyclone to
steer Hilda westward for the next couple of days with a slight bend
toward the west-northwest after 36 hours. In about 72 hours, the
cyclone should move around the western end of the ridge and
encounter a break in this feature at the end of the forecast period.
This pattern should cause Hilda to turn northwestward with a
decrease in forward speed by 96 hours. The GFS-based guidance shows
a stronger ridge and a west-southwestward to westward track during
the next 2 to 3 days, while the ECMWF has a weaker ridge and a
track farther north. The official forecast is closer to the ECMWF
solution and near but faster than the previous one through 72 hours.
Overall, the NHC forecast lies to the right of the multi-model
consensus, which is dominated by the GFS guidance. After 72 hours,
the official track is near the multi-model consensus but not as far
west as the GFS/ECMWF model solutions.

Large-scale dynamic and thermodynamic factors are forecast to be
conducive for intensification through for the next 72 hours or so,
except for a somewhat drier lower to middle troposphere along
Hilda's path in 2 to 3 days. When the cyclone gains latitude late
in the forecast period, it should begin to weaken due to increasing
southwesterly shear associated with a mid- to upper-level trough
expected to be near the longitude of Hawaii. The official intensity
forecast is higher than the previous one through 72 hours and is
higher than the multi-model consensus, but little change was made to
the intensity forecast late in the period.


FORECAST POSITIONS AND MAX WINDS

INIT 06/1500Z 12.7N 132.3W 35 KT 40 MPH
12H 07/0000Z 12.9N 133.6W 45 KT 50 MPH
24H 07/1200Z 13.0N 135.8W 50 KT 60 MPH
36H 08/0000Z 13.5N 137.9W 55 KT 65 MPH
48H 08/1200Z 14.1N 139.9W 60 KT 70 MPH
72H 09/1200Z 15.4N 144.2W 65 KT 75 MPH
96H 10/1200Z 17.1N 146.8W 65 KT 75 MPH
120H 11/1200Z 18.8N 149.4W 55 KT 65 MPH

$$
Forecaster Kimberlain

[galaxy401]

Another storm the CPHC will likely monitor soon. Much busier than the last couple years.

[srainhoutx]

Looks like the 53rd Weather Reconnaissance crew will be staying at Hickam Field a bit longer...

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WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1100 AM EDT THU 06 AUGUST 2015
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
         VALID 07/1100Z TO 08/1100Z AUGUST 2015
         TCPOD NUMBER.....15-072

II. PACIFIC REQUIREMENTS
    1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
    2. SUCCEEDING DAY OUTLOOK.....NEGATIVE.
    3. ADDITIONAL DAY OUTLOOK: BEGIN 12-HRLY FIXES ON TROPICAL
       STORM HILDA AT 10/0600Z NEAR 16.6N 146.1W.


[Alyono]

a little more concerned about this one than I was with Guillermo

[Yellow Evan]

a little more concerned about this one than I was with Guillermo

Question will be how much dry air holds this in check?

[Yellow Evan]

----- Current Analysis -----
Date : 06 AUG 2015 Time : 160000 UTC
Lat : 12:42:49 N Lon : 132:28:59 W


CI# /Pressure/ Vmax
2.7 /1005.8mb/ 39.0kt


Final T# Adj T# Raw T#
2.7 2.8 2.9

Center Temp : -66.0C Cloud Region Temp : -61.1C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

[MGC]

Hawaii luck is eventually going to run out. Not saying Hilda is going to be the one.

On a side note, Hilda in 1964 was the first hurricane I experienced. We got a near miss in New Orleans. Hilda started me hurricane tracking. Got a big test the next year with Betsy. Betsy taught me what a hurricane can do. Camille and Katrina only reinforced that belief......MGC

[Alyono]

based upon the windsat pass, I'd say winds are around 45 kts now

[Yellow Evan]

based upon the windsat pass, I'd say winds are around 45 kts now

WindSat isn't reliable AFAIK unless I'm wrong.

[Yellow Evan]

06/1800 UTC 12.6N 132.8W T2.5/2.5 10E -- East Pacific

[Yellow Evan]

89GHz
EP, 10, 201508061800, 10, DVTS, CI, , 1260N, 13280W, , 2, 35, 2, , , , , , , , , , , , , , , , , E, SAB, JV, VIM, 3, 2525 /////, , , GOES15, LLCC, T, DT=2.5 BO CBND MET=2.5 PT=3.0 FTBO DT
EP, 10, 201508061800, 10, DVTS, CI, , 1270N, 13250W, , 3, 35, 2, 1005, 2, DVRK, , , , , , , , , , , , , , E, TAFB, DS, VI, 5, 2525 /////, , , GOES15, CSC, T,

Probs still 35 knts, though it looks really nice.

[Alyono]

based upon the windsat pass, I'd say winds are around 45 kts now

WindSat isn't reliable AFAIK unless I'm wrong.

I've noticed it tends to underdo the winds. I saw a 40 kt vector there

Not entirely agreeing with the 2.5 either. This looks like a solid 3.0 to me

[Yellow Evan]

This looks like a solid 3.0 to me

That I agree with. Methinks the NHC will go 40 knots actually.

[Yellow Evan]

014,
EP, 10, 2015080618, , BEST, 0, 127N, 1328W, 45, 1001, TS, 34, NEQ, 30, 20, 20, 30, 1009, 175, 30, 0, 0, E, 0, , 0, 0, HILDA, D, 0, , 0, 0, 0, 0, genesis-num, 014,


Wow! If only the JTWC would do stuff like this...

[Kingarabian]