CPAC: ISELLE - Post-Tropical

[Equilibrium]

Something else to consider

OurAmazingPlanet.

Most hurricanes that make landfall create tornadoes, It's pretty uncommon to not have tornadoes with these. Tornadoes mostly form over land, instead of over water, because the land slows down surface-level winds, creating even more wind shear Tornadoes form wherever these pre-existing supercells happen to be but meteorologists are still unable to predict exactly where tornados will strike.

These twisters usually form in the swirling bands of rain outside the cyclone, typically in the "front-right quadrant" of the storm, Iif the storm is moving north, you're most likely to find tornadoes to the northeast of the cyclone's eye.

[Alyono]

models initialized at 85 kts

[supercane4867]

CIMSS analysis indicate still no signs of increasing shear at all and may actually decreased a bit

[supercane4867]

Up to Cat.2

09E ISELLE 140807 0600 17.9N 148.3W EPAC 85 980

[somethingfunny]

I'm not so sure about this hurricane's health, with this new gash having opened up:

[Equilibrium]

I'm not so sure about this hurricane's health, with this new gash having opened up:

Its looked a lot worse and its still hauling along as a hurricane.

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.org. For official information, please refer to the NHC and NWS products

[WeatherGuesser]

When is the next advisory due? My brain's not tuned to Coconut time.

[Brent]

When is the next advisory due? My brain's not tuned to Coconut time.

5am ET... advisories are issued at the same time as if the NHC was issuing them actually with the time difference.

[Brent]

BULLETIN
HURRICANE ISELLE ADVISORY NUMBER 29
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP092014
1100 PM HST WED AUG 06 2014

...ISELLE STILL HEADING FOR THE BIG ISLAND...MAINTAINING HURRICANE
INTENSITY...


SUMMARY OF 1100 PM HST...0900 UTC...INFORMATION
-----------------------------------------------
LOCATION...18.1N 149.1W
ABOUT 405 MI...655 KM ESE OF HILO HAWAII
ABOUT 615 MI...985 KM ESE OF HONOLULU HAWAII
MAXIMUM SUSTAINED WINDS...90 MPH...150 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 18 MPH...30 KM/H
MINIMUM CENTRAL PRESSURE...982 MB...29.00 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

NONE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WARNING IS IN EFFECT FOR...
* HAWAII COUNTY

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* MAUI COUNTY...INCLUDING THE ISLANDS OF MAUI...MOLOKAI...LANAI...
AND KAHOOLAWE.
* OAHU

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* KAUAI COUNTY INCLUDING THE ISLANDS OF KAUAI AND NIIHAU.

A HURRICANE WARNING MEANS THAT HURRICANE CONDITIONS ARE EXPECTED
SOMEWHERE WITHIN THE WARNING AREA. PREPARATIONS TO PROTECT LIFE AND
PROPERTY SHOULD BE RUSHED TO COMPLETION.

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE
EXPECTED SOMEWHERE WITHIN THE WARNING AREA WITHIN 36 HOURS.

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE SOMEWHERE WITHIN THE WATCH AREA WITHIN THE NEXT 48 HOURS.

INTERESTS IN THE NORTHWEST HAWAIIAN ISLANDS SHOULD MONITOR THE
PROGRESS OF ISELLE.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...PLEASE MONITOR
PRODUCTS ISSUED BY THE NATIONAL WEATHER SERVICE OFFICE IN
HONOLULU HAWAII.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1100 PM HST...0900 UTC...THE CENTER OF HURRICANE ISELLE WAS
LOCATED NEAR LATITUDE 18.1 NORTH...LONGITUDE 149.1 WEST. ISELLE IS
MOVING TOWARD THE WEST-NORTHWEST NEAR 18 MPH...30 KM/H...AND THIS
MOTION IS EXPECTED TO CONTINUE THROUGH THURSDAY...WITH SOME SLOWING
IN FORWARD SPEED ON FRIDAY. ON THE FORECAST TRACK...THE CENTER OF
ISELLE IS EXPECTED TO PASS VERY NEAR OR OVER THE BIG ISLAND THURSDAY
NIGHT...AND PASS JUST SOUTH OF THE SMALLER ISLANDS FRIDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 90 MPH...150 KM/H...WITH HIGHER
GUSTS. SOME WEAKENING IS FORECAST DURING THE NEXT 48 HOURS...BUT
ISELLE IS NOW EXPECTED TO BE A HURRICANE AS IT PASSES NEAR OR OVER
THE BIG ISLAND.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 140
MILES...220 KM.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 982 MB...29.00 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...THE ONSET OF TROPICAL STORM CONDITIONS IS EXPECTED ON THE
BIG ISLAND OF HAWAII THURSDAY AFTERNOON...WITH HURRICANE CONDITIONS
EXPECTED THURSDAY NIGHT. TROPICAL STORM CONDITIONS ARE EXPECTED
OVER MAUI COUNTY THURSDAY NIGHT...AND FOR OAHU LATE THURSDAY NIGHT
AND FRIDAY. TROPICAL STORM CONDITIONS ARE POSSIBLE FOR KAUAI COUNTY
ON FRIDAY.

SURF...SWELLS GENERATED BY ISELLE WILL CONTINUE TO BUILD ALONG EAST
FACING SHORES AND VERY LARGE...DAMAGING SURF IS EXPECTED ALONG
MAINLY EAST AND SOUTHEAST FACING SHORES STARTING EARLY THURSDAY.

RAINFALL...RAINFALL TOTALS OF 5 TO 8 INCHES...WITH ISOLATED MAXIMUM
AMOUNTS TO 12 INCHES...ARE EXPECTED ALONG THE TRACK OF ISELLE.
THESE RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AS WELL AS
ROCK AND MUD SLIDES.

STORM SURGE...THE COMBINATION OF A DANGEROUS STORM SURGE AND THE
TIDE WILL CAUSE NORMALLY DRY AREAS NEAR THE COAST TO BE FLOODED BY
RISING WATERS. THE WATER COULD REACH THE FOLLOWING HEIGHTS ABOVE
GROUND IF THE PEAK SURGE OCCURS AT THE TIME OF HIGH TIDE...

BIG ISLAND WINDWARD AND KAU...1 TO 3 FT

THE HIGHEST WATER WILL OCCUR ALONG THE IMMEDIATE COAST IN AREAS OF
ONSHORE FLOW. THE SURGE WILL BE ACCOMPANIED BY LARGE AND DAMAGING
WAVES. SURGE RELATED FLOODING DEPENDS ON THE RELATIVE TIMING OF THE
SURGE AND THE TIDAL CYCLE...AND CAN VARY GREATLY OVER SHORT
DISTANCES.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...200 AM HST.
NEXT COMPLETE ADVISORY...500 AM HST.
$$
FORECASTER BIRCHARD

[Kingarabian]

[WeatherGuesser]

List of closures: http://westhawaiitoday.com/hurricane-se ... -s-arrival

[supercane4867]

Up to Cat.2

09E ISELLE 140807 0600 17.9N 148.3W EPAC 85 980

They've decided to keep at 80kt in official advisory

[WeatherGuesser]

At 1100 pm HST, 0900 UTC, the center of hurricane Iselle was located near latitude 18.1 north, longitude 149.1 west. Iselle is moving toward the west-northwest near 18 mph, 30 km/h, and this motion is expected to continue through Thursday, with some slowing in forward speed on Friday. On the forecast track, the center of Iselle is expected to pass very near or over the Big Island Thursday night, and pass just south of the smaller islands Friday.

Maximum sustained winds are near 90 mph, 150 km/h, with higher gusts. Some weakening is forecast during the next 48 hours, but Iselle is now expected to be a hurricane as it passes near or over the Big Island.

Hurricane force winds extend outward up to 45 miles, 75 km, from the center, and tropical storm force winds extend outward up to 140 miles, 220 km.

The estimated minimum central pressure is 982 mb, 29.00 inches.

http://www.prh.noaa.gov/cphc/tcpages/ar ... 070840.php

[Brent]

HURRICANE ISELLE DISCUSSION NUMBER 29
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP092014
1100 PM HST WED AUG 06 2014

ISELLE CONTINUES TO MAINTAIN HURRICANE STRENGTH. AN AIR FORCE
RECONNAISSANCE AIRCRAFT FOUND MAXIMUM FLIGHT LEVEL WINDS CLOSE TO
100 KT IN THE NORTHEAST QUADRANT NEAR 06Z...WHICH CORRELATES TO A
90 KT SURFACE WIND. MAXIMUM SFMR OBSERVATIONS WERE CLOSER TO 75 KT...
AND DVORAK SATELLITE INTENSITY ESTIMATES RANGE FROM 4.5/77 KT
TO 5.0/90 KT...WITH ALL AGENCIES INDICATING DEVELOPMENT OVER THE
PAST 24 HOURS. WHILE THE SYNOPTIC INTENSITY WAS SET AT 85 KT...THE
ADVISORY INTENSITY IS DEEMED TO BE 80 KT DUE TO A SOMEWHAT DEGRADED
SATELLITE APPEARANCE SINCE 06Z.

INITIAL MOTION ESTIMATE IS 285/16 KT...WITH THE FORWARD SPEED OF
MOTION UNCHANGED FROM THE PREVIOUS ADVISORY. ISELLE CONTINUES TO BE
DRIVEN GENERALLY WESTWARD BY A MID LEVEL RIDGE CENTERED TO THE
NORTHEAST OF THE SYSTEM...WITH ISELLE EXPECTED TO REACH THE
SOUTHWEST PERIPHERY OF THE RIDGE IN ABOUT 48 HOURS...AFTER WHICH THE
FORWARD MOTION IS EXPECTED TO SLOW. ON DAYS 3 AND 4 A LOW ALOFT IS
FORECAST TO CUT OFF AND MOVE SOUTH AHEAD OF ISELLE/S TRACK...WHICH
WILL BE RESPONSIBLE FOR INTRODUCING INCREASED SHEAR AND A SOMEWHAT
WEAKER STEERING FLOW. LITTLE CHANGE TO THE SHORT TERM FORECAST TRACK
HAS BEEN FROM THE PREVIOUS ADVISORY...WITH THE GUIDANCE REMAINING
TIGHTLY CLUSTERED MOVING THE CENTER OF ISELLE OVER THE BIG ISLAND
LATE THURSDAY. ON DAYS 3 THROUGH 5 THE UPDATED FORECAST TRACK
INDICATES A SLOWING IN FORWARD MOTION...AND AN ADJUSTMENT TO THE
RIGHT OF THE PREVIOUS FORECAST WAS MADE.
THE INTENSITY FORECAST REMAINS A CHALLENGE. A GENERAL WEAKENING
TREND IS STILL EXPECTED THROUGH THE FORECAST PERIOD...BUT THE LATEST
FORECAST MAINTAINS ISELLE AS A HURRICANE AS IT APPROACHES WINDWARD
BIG ISLAND ON THURSDAY. ISELLE HAS BEEN WEDGED BETWEEN A RIDGE ALOFT
CENTERED WEST OF THE MAIN HAWAIIAN ISLANDS AND A RIDGE CENTERED OVER
THE BAJA PENINSULA OVER THE PAST 24 TO 36 HOURS. ISELLE MOVED UNDER
A COL BETWEEN THESE RIDGES EARLIER TODAY...WHICH ALLOWED SHEAR TO
RELAX OVER THE SYSTEM...LEADING TO A BRIEF INTENSIFICATION TREND.
GLOBAL MODELS ARE OFFERING CONFLICTING SIGNALS WITH RESPECT TO THE
JUXTAPOSITION OF ISELLE AND THIS COL. THE GFS IS INDICATING THE
RIDGE WEST OF HAWAII WILL SHIFT WEST AND MAINTAIN THE COL AND
RELATIVELY LIGHT SHEAR NORTH OF ISELLE...WHILE THE ECMWF INDICATES
LITTLE MOVEMENT OF THE RIDGE...INDICATING THAT STRONGER SHEAR LIES
ALONG THE FUTURE PATH OF ISELLE. LATEST SATELLITE IMAGES SHOW HIGH
CLOUDS STREAMING RAPIDLY SOUTHWEST FROM THE TOP OF ISELLE...WHICH
WOULD INDICATE IT IS CURRENTLY FEELING THE SHEARING EFFECTS OF THE
RIDGE TO THE WEST. THE FORECAST ANTICIPATES THE SHEAR TO INCREASE
AFTER 24 HOURS...LEADING TO A MORE RAPID WEAKENING.


FORECAST POSITIONS AND MAX WINDS

INIT 07/0900Z 18.1N 149.1W 80 KT 90 MPH
12H 07/1800Z 18.7N 151.5W 75 KT 85 MPH
24H 08/0600Z 19.5N 154.8W 70 KT 80 MPH
36H 08/1800Z 20.3N 157.8W 60 KT 70 MPH
48H 09/0600Z 21.0N 160.2W 50 KT 60 MPH
72H 10/0600Z 22.2N 164.6W 45 KT 50 MPH
96H 11/0600Z 23.8N 169.7W 35 KT 40 MPH
120H 12/0600Z 26.0N 175.5W 30 KT 35 MPH

$$
FORECASTER BIRCHARD

[Equilibrium]

070400Z POSITION NEAR 17.7N 147.8W.
HURRICANE 09E (ISELLE), LOCATED APPROXIMATELY 495 NM EAST-
SOUTHEAST OF HILO, HAS TRACKED WEST-NORTHWESTWARD AT 18 KNOTS
OVER THE PAST SIX HOURS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 070000Z
IS 32 FEET. NEXT WARNINGS AT 071000Z, 071600Z, 072200Z AND 080400Z.
REFER TO TROPICAL STORM 07E (GENEVIEVE) WARNINGS (WTPN31 PGTW)
FOR SIX-HOURLY UPDATES. REFER TO TROPICAL CYCLONE 10E (JULIO)
WARNINGS (WTPN33 PGTW) FOR SIX-HOURLY UPDATES.//


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.org. For official information, please refer to the NHC and NWS products.

[WeatherGuesser]

24H 08/0600Z 19.5N 154.8W 70 KT 80 MPH
36H 08/1800Z 20.3N 157.8W 60 KT 70 MPH

They're not knocking it down much as it goes over.

Peak elevation is somewhere near 19.5, 155.5 so the forecast points above should go right over it.

[somethingfunny]

We now officially have an H over the Big Island in 24 hours on the forecast.

I'm very curious about these flight-level winds that are upwards of 100kt, and what those would do when encountering topography as high as Mauna Loa/Kea..

[Kingarabian]

Pressures have gone up to an average of 984.

[Equilibrium]

I'm very curious about these flight-level winds that are upwards of 100kt, and what those would do when encountering topography as high as Mauna Loa/Kea..

Downslope winds.

[somethingfunny]

I'm very curious about these flight-level winds that are upwards of 100kt, and what those would do when encountering topography as high as Mauna Loa/Kea..

Downslope winds.

That's my fear, there could be some hellacious wind gusts on Hawaii even coming from a storm with weak "surface" winds. I wonder how far downslope those winds would get - could they threaten major communities closer to sea level?Aside from the threat of freak gusts, sustained winds just at a few thousand feet elevation could be a full hurricane wind category higher.

Here's a weather station and some webcams atop Mauna Kea, over 12,000 feet elevation: http://www.ifa.hawaii.edu/info/vis/

Does anybody know if the Mauna Kea Observatory is going to be evacuated? If it isn't.... oh man oh man oh man there had BETTER be TV reporters stationed up there! I've been trying to find more weather stations from up there. The highest official reporting station is Bradshaw Army Airfield at about 6,000 feet elevation, in the valley between Mauna Loa and Mauna Kea near the center of the island.