EPAC: GUILLERMO - Post-Tropical

[Kingarabian]

Hawaii just so fortunate that these storms keep missing.

Especially since our building codes here are crap and we've had cases where 30mph wind gusts tore off roofs.

[Kingarabian]

WTPA44 PHFO 040244
TCDCP4

TROPICAL STORM GUILLERMO DISCUSSION NUMBER 21
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP092015
500 PM HST MON AUG 03 2015

LITTLE HAS CHANGED THROUGH THE DAY WITH GUILLERMO LOOKING VERY
RAGGED IN THE SATELLITE IMAGES. DEEP CONVECTION HAS BEEN PULSING
NORTHEAST OF THE CENTER...WHICH HAS BEEN VERY DIFFICULT TO LOCATE
WITHOUT THE BENEFIT OF AIRCRAFT RECON. A VERY TIMELY AMSU PASS AT
0003 UTC WAS THE MAIN BASIS FOR THE INITIAL POSITION. SUBJECTIVE
DVORAK INTENSITY ESTIMATES FROM PHFO...SAB AND JTWC WERE ALL AT 55
KT AND IS THE INITIAL INTENSITY FOR THIS PACKAGE.

GUILLERMO IS MOVING THROUGH A BREAK IN THE RIDGE ALOFT WITH AN
INITIAL MOTION OF 310/09 KT. THE LATEST OBJECTIVE AIDS HAVE SHIFTED
FARTHER NORTH THAN THE PREVIOUS FORECAST WITH THE HWRF MAKING THE
LARGEST LEAP TO BECOME A NORTHERN OUTLIER THROUGH 36 HOURS. THE
CURRENT FORECAST IS AN UPDATE OF THE PREVIOUS PACKAGE AND IS CLOSE
TO THE GFS AND ECMWF TRACK THROUGH 36 HOURS...THEN SOUTH OF THE
DYNAMICAL AIDS FOR THE LATER FORECAST PERIODS. THIS FORECAST TRACK
ACCOUNTS FOR THE POSSIBILITY THAT THE INCREASING VERTICAL SHEAR
ALONG THE FORECAST TRACK COULD WEAKEN GUILLERMO A LITTLE FASTER THAN
THE DYANMICAL AIDS FORECAST AND WILL FOLLOW A PATH WEIGHTED MORE
TOWARD THE LOWER LEVEL STEERING CURRENT.

ALONG THE FORECAST TRACK...GUILLERMO WILL CONTINUE TO MOVE
TOWARD INCREASINGLY HOSTILE VERTICAL SHEAR. SHIPS SHEAR FORECASTS
INDICATE 25 KT BY 12 HOURS AND MORE THAN 30 KT BY 48 HOURS. THIS IS
CONSISTENT WITH UPPER LEVEL WINDS PROJECTED BY THE GLOBAL MODELS.
THE FORECAST CALLS FOR CONTINUED WEAKENING OF GUILLERMO AS IT
APPROACHES THE MAIN HAWAIIAN ISLANDS AND IS IN LINE WITH THE
PREVIOUS FORECAST.

WHILE THE FORECAST TRACK KEEPS THE CENTER OF GUILLERMO NORTHEAST OF
THE MAIN HAWAIIAN ISLANDS...A SIGNIFICANT DEVIATION TO THE LEFT OF
THE TRACK WOULD HAVE THE POTENTIAL TO BRING TROPICAL STORM
CONDITIONS TO THE BIG ISLAND OR MAUI COUNTY. WHEN ACCOUNTING
FOR THE SIZE OF THE SYSTEM...THERE REMAINS ENOUGH UNCERTAINTY TO
WARRANT ISSUANCE OF A TROPICAL STORM WATCH FOR HAWAII AND MAUI
COUNTIES. OTHER COUNTIES MAY BE ADDED LATER AS NEEDED.


FORECAST POSITIONS AND MAX WINDS

INIT 04/0300Z 18.1N 147.4W 55 KT 65 MPH
12H 04/1200Z 18.8N 148.7W 50 KT 60 MPH
24H 05/0000Z 19.8N 150.4W 45 KT 50 MPH
36H 05/1200Z 20.6N 152.1W 45 KT 50 MPH
48H 06/0000Z 21.5N 154.0W 40 KT 45 MPH
72H 07/0000Z 23.5N 157.9W 35 KT 40 MPH
96H 08/0000Z 25.5N 162.0W 30 KT 35 MPH
120H 09/0000Z 26.5N 166.5W 25 KT 30 MPH

$$
FORECASTER KODAMA

[Kingarabian]

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

A TROPICAL STORM WATCH HAS BEEN ISSUED FOR HAWAII COUNTY AND MAUI
COUNTY.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

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

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

INTERESTS ELSEWHERE IN THE MAIN HAWAIIAN ISLANDS SHOULD MONITOR THE
PROGRESS OF GUILLERMO. WATCHES MAY BE REQUIRED FOR ADDITIONAL
ISLANDS LATER TONIGHT OR EARLY TUESDAY.

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

[Yellow Evan]

Storms keep missing Hawaii because it's small.

[Kingarabian]

Storms keep missing Hawaii because it's small.

If you look at the past recent storms, either the shear saves Hawaii or that sub-tropical building or breaking at the perfect time.

Storms have gotten really close.

Not complaining though. Just worried about the cry wolf effect.

[Yellow Evan]

Storms keep missing Hawaii because it's small.

If you look at the past recent storms, either the shear saves Hawaii or that sub-tropical building or breaking at the perfect time.

Storms have gotten really close.

Not complaining though. Just worried about the cry wolf effect.

Well I could flip it the other way around and say that Iniki reached the breaking point at the right time to devastate Hawaii.

What I'd be concerned about is in future years storms from the east in years with less of a GHS (GHS believe it or not is usually pretty strong in super Ninos). Giving how much the waters near Hawaii have warmed the past 10 years, SST's are less of an issue.

[Kingarabian]

[Yellow Evan]

WTPA34 PHFO 040557
TCPCP4

BULLETIN
TROPICAL STORM GUILLERMO INTERMEDIATE ADVISORY NUMBER 21A
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP092015
800 PM HST MON AUG 03 2015

...GUILLERMO CONTINUES TO MOVE NORTHWEST...


SUMMARY OF 800 PM HST...0600 UTC...INFORMATION
----------------------------------------------
LOCATION...18.5N 147.5W
ABOUT 500 MI...805 KM E OF HILO HAWAII
ABOUT 700 MI...1125 KM ESE OF HONOLULU HAWAII
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...NW OR 310 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...991 MB...29.27 INCHES


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

NONE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

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

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

INTERESTS ELSEWHERE IN THE MAIN HAWAIIAN ISLANDS SHOULD MONITOR THE
PROGRESS OF GUILLERMO. WATCHES MAY BE REQUIRED FOR ADDITIONAL
ISLANDS ON TUESDAY.

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


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 800 PM HST...0600 UTC...THE CENTER OF TROPICAL STORM GUILLERMO
WAS LOCATED NEAR LATITUDE 18.5 NORTH...LONGITUDE 147.5 WEST.
GUILLERMO IS MOVING TOWARD THE NORTHWEST NEAR 10 MPH...17 KM/H...AND
THIS MOTION IS EXPECTED TO CONTINUE THROUGH WEDNESDAY. ON THE
FORECAST TRACK...THE CENTER OF GUILLERMO IS EXPECTED TO PASS
APPROXIMATELY 140 MILES NORTHEAST OF THE BIG ISLAND ON WEDNESDAY...
AND ABOUT 100 MILES NORTHEAST OF MAUI ON WEDNESDAY NIGHT.

MAXIMUM SUSTAINED WINDS ARE NEAR 65 MPH...100 KM/H...WITH HIGHER
GUSTS. STEADY WEAKENING IS EXPECTED OVER THE NEXT COUPLE OF DAYS.

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

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 991 MB...29.27 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...TROPICAL STORM CONDITIONS ARE POSSIBLE ON THE BIG ISLAND OF
HAWAII AND THE ISLANDS OF MAUI...MOLOKAI...LANAI AND KAHOOLAWE IN
MAUI COUNTY ON WEDNESDAY.

RAINFALL...TOTAL RAINFALL AMOUNTS OF 1 TO 3 INCHES...WITH ISOLATED
MAXIMUM AMOUNTS NEAR 7 INCHES MAINLY IN HIGHER TERRAIN...ARE
POSSIBLE IN THE WATCH AREA.

SURF...LARGE SWELLS TRAVELING AHEAD OF TROPICAL STORM GUILLERMO
WILL SPREAD FROM EAST TO WEST OVER THE HAWAIIAN ISLANDS THROUGH
MID WEEK. THIS WILL PRODUCE LARGE AND POTENTIALLY LIFE THREATENING
SURF ALONG EAST FACING SHORES.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 PM HST.

$$

FORECASTER BIRCHARD/JELSEMA

[Kingarabian]

Pressure is at 990.

And I swear it looks like it's heading due north now.

[Yellow Evan]

Pressure 989-990 mbar, but boy, this is weak. Likely 45 knts.

[Kingarabian]

Pressure 989-990 mbar, but boy, this is weak. Likely 45 knts.

Lots of lag then. That pressure should be in the higher 90's.

[Kingarabian]

Both the 00z GFS and Euro keeps this a bit more south and west than their previous runs.

[Kingarabian]

68kt flight level and SFMR winds found.

[cycloneye]

TROPICAL STORM GUILLERMO DISCUSSION NUMBER 22
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP092015
1100 PM HST MON AUG 03 2015

THE LATEST INFRARED SATELLITE PRESENTATION OF GUILLERMO HAS
IMPROVED SINCE THE LAST ADVISORY...WITH PERSISTENT DEEP CONVECTION
REMAINING NEAR AND TO THE NORTHEAST OF THE LOW LEVEL CIRCULATION
CENTER. IT REMAINS EVIDENT THAT GUILLERMO IS UNDERGOING QUITE A BIT
OF WESTERLY WIND SHEAR WITH THE DEEP CONVECTION TILTING THE SYSTEM
OFF TO THE NORTHEAST...AND THIS IS SHOWN WELL BY THE LATEST
UW-CIMSS VERTICAL WIND SHEAR ANALYSIS INDICATING 20 KNOTS OF SHEAR
FROM 265 DEGREES. DESPITE THE VERTICAL WIND SHEAR PRESENT OVER THE
SYSTEM...DVORAK CLASSIFICATIONS FROM PHFO...SAB...AND JTWC CONTINUE
TO INDICATE T NUMBERS OF 3.5 OR 55 KNOTS. THE FINAL DECISION ON THE
INITIAL INTENSITY WAS BASED HEAVILY ON TIMELY DATA FROM THE U.S.
53RD WEATHER RECONNAISSANCE AIRCRAFT WHICH IS CURRENTLY SAMPLING
THE INNER CORE OF GUILLERMO. THE AIRCRAFT FOUND MAX FLIGHT LEVEL
WINDS OF 72 KNOTS...33 NM NORTHEAST OF THE CENTER OF CIRCULATION.
ADJUSTING THE FLIGHT LEVEL WINDS TO THE SURFACE YIELDS SURFACE WINDS
OF 58 MPH. ADDITIONALLY...SFMR DATA FROM THE AIRCRAFT INDICATED
SURFACE WINDS AS STRONG AS 68 KNOTS TO THE NORTHEAST OF THE CENTER.
SOME OF THE SFMR WINDS MAY HAVE BEEN RAINFALL CONTAMINATED...AND AS
A RESULT...THE INITIAL INTENSITY OF GUILLERMO UTILIZED A BLEND OF
THE FLIGHT LEVEL AND SFMR WINDS AND WAS SET AT 60 KNOTS...JUST BELOW
HURRICANE STRENGTH.

THE INITIAL POSITION OF THE SYSTEM WAS BASED ON CENTER FIX
POSITIONS FROM THE RECONNAISSANCE AIRCRAFT AS WELL...WITH AN INITIAL
MOTION TOWARD THE NORTHWEST OR 325 DEGREES AT 10 KNOTS. THE LATEST
MODEL GUIDANCE SHOWS THE TRACK SHIFTING BACK SLIGHTLY TOWARD THE
LEFT OR CLOSER TO THE HAWAIIAN ISLANDS...BUT THESE MODELS APPEAR TO
BE STRUGGLING WITH THE CURRENT MOTION. THE SYSTEMS MOTION APPEARS
TO BE DRIVEN LARGELY BY A WEAKNESS IN THE MID-UPPER LEVEL RIDGE
WHICH EXTENDS FROM GUILLERMO OFF TO THE NORTHWEST TO A LOCATION
NEAR 30N157W. THIS WEAKNESS IN THE RIDGE IS DRIVING THE MOTION OF
GUILLERMO AT THE CURRENT TIME DUE TO THE DEEP CONVECTION IN PLACE
NEAR AND TO THE NORTHEAST OF THE CIRCULATION CENTER. AS A
RESULT...THE OFFICIAL FORECAST FOLLOWS A DIRECTION ON THE NORTH
SIDE OF THE GUIDANCE ENVELOPE THROUGH 24 HOURS WHICH ASSUMES
MAINTENANCE OF DEEP CONVECTION AND INTERACTION WITH THE WEAKNESS IN
THE MID-UPPER LEVEL RIDGE. BEYOND 24 HOURS AS WESTERLY WIND SHEAR
IS FORECAST TO INCREASE SIGNIFICANTLY OVER THE SYSTEM...A SHIFT
TOWARD THE WEST-NORTHWEST IS EXPECTED...WHICH IS VERY CLOSE TO THE
PREVIOUS OFFICIAL FORECAST TRACK. ON THIS TRACK...THE CLOSEST
APPROACH OF GUILLERMO REMAINS WELL TO THE NORTHEAST OF ALL THE
HAWAIIAN ISLANDS...SO THE WATCH WAS MAINTAINED WITH THIS ADVISORY
PACKAGE. IF THE TRACK SHIFTS BACK CLOSER TO THE ISLANDS LATER
TONIGHT OR TUESDAY...A TROPICAL STORM WARNING MAY BE NEEDED FOR THE
BIG ISLAND OR MAUI COUNTY...BUT THIS IS NOT ANTICIPATED AT THIS
TIME.

THE INTENSITY FORECAST FOR GUILLERMO IS A BLEND OF ICON AND HWRF
INTENSITY GUIDANCE ALONG WITH WEIGHT GIVEN TO THE PREVIOUS OFFICIAL
FORECAST. THE GLOBAL MODELS ARE SHOWING THE POTENTIAL FOR
DECREASING VERTICAL WIND SHEAR LATER TONIGHT WITH A WINDOW OF
OPPORTUNITY FOR STRENGTHENING POSSIBLE THROUGH WEDNESDAY 05/18Z.
AFTER 05/18Z...VERTICAL WIND SHEAR IS FORECAST TO STRENGTHEN TO 25
KNOTS OR GREATER OVER THE SYSTEM...AND THIS SHOULD LEAD TO STEADY
WEAKENING OF THE SYSTEM THEREAFTER. GIVEN THE POTENTIAL FOR
WEAKENING OF THE SHEAR ALONG WITH FAVORABLE SEA SURFACE
TEMPERATURES OF AROUND 82 DEGREES FAHRENHEIT BASED ON MODIS DATA
FROM EARLIER THIS AFTERNOON...IT IS NOT OUT OF THE QUESTION THAT
GUILLERMO COULD BECOME A HURRICANE OVER THE NEXT 12 HOURS. THE
OFFICIAL INTENSITY FORECAST WILL SHOW LITTLE CHANGE IN STRENGTH
HOWEVER OVER THE NEXT 12 HOURS...THEN SHOW SLOW BUT STEADY WEAKENING
THROUGH 120 HOURS.

ANOTHER RECONNAISSANCE AIRCRAFT MISSION INTO GUILLERMO IS SCHEDULED
FOR 12Z TUESDAY MORNING. THE VALUABLE DATA TRANSMITTED IN REAL-TIME
FROM THESE MISSIONS WILL HELP US TO BETTER DETERMINE THE
LOCATION...INTENSITY AND SIZE OF THE TROPICAL STORM...ALONG WITH
ANY POTENTIAL IMPACTS TO THE HAWAIIAN ISLANDS.




FORECAST POSITIONS AND MAX WINDS

INIT 04/0900Z 18.9N 147.7W 60 KT 70 MPH
12H 04/1800Z 19.7N 148.9W 60 KT 70 MPH
24H 05/0600Z 20.5N 150.7W 50 KT 60 MPH
36H 05/1800Z 21.3N 152.6W 45 KT 50 MPH
48H 06/0600Z 22.2N 154.5W 40 KT 45 MPH
72H 07/0600Z 24.2N 158.5W 35 KT 40 MPH
96H 08/0600Z 26.0N 163.0W 30 KT 35 MPH
120H 09/0600Z 27.0N 167.5W 25 KT 30 MPH

$$
FORECASTER JELSEMA/BIRCHARD

[AbcdeerHI]

1st pass - 992mb
2nd pass - 995mb
3rd pass - 989mb

using the ruler on google earth the storm has made slight wobble to the left, possibly due to recent convection expanding. initally the heading was 330 degrees between 1st and 2nd pass. from 2nd -3rd pass its 325 degrees. thought this was interesting since the discussion they mentioned the shear possibly weakening until 5/18z. its really to early to tell if this holds any merits.

Product: Air Force Vortex Message (URPN12 KNHC)
Transmitted: 4th day of the month at 10:28Z
Agency: United States Air Force
Aircraft: Lockheed WC-130J Hercules with reg. number AF97-5305
Storm Number & Year: 09 in 2015
Storm Name: Guillermo (flight in the Northeast Pacific basin)
Mission Number: 6
Observation Number: 17
A. Time of Center Fix: 4th day of the month at 10:11:00Z
B. Center Fix Coordinates: 19°06'N 147°47'W (19.1N 147.7833W)
C. Minimum Height at Standard Level: 1,332m (4,370ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 57kts (~ 65.6mph)
E. Location of the Estimated Maximum Surface Wind: 53 nautical miles (61 statute miles) to the ENE (66°) of center fix
F. Maximum Flight Level Wind Inbound: From 153° at 73kts (From the SSE at ~ 84.0mph)
G. Location of Maximum Flight Level Wind Inbound: 22 nautical miles (25 statute miles) to the E (89°) of center fix
H. Minimum Sea Level Pressure: 989mb (29.21 inHg) - Extrapolated
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 17°C (63°F) at a pressure alt. of 1,522m (4,993ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 25°C (77°F) at a pressure alt. of 1,520m (4,987ft)
K. Dewpoint Temp & Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Not Available
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Wind, Pressure and Temperature
N. Fix Level: 850mb
O. Navigational Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 1 nautical mile

Remarks Section - Remarks That Were Decoded...
Maximum Flight Level Wind: 73kts (~ 84.0mph) which was observed 22 nautical miles (25 statute miles) to the E (89°) from the flight level center at 9:49:00Z
Sea Level Pressure Extrapolation From: 850mb
Maximum Flight Level Temp: 27°C (81°F) which was observed 9 nautical miles to the ESE (114°) from the flight level center

Remarks Section - Additional Remarks...
NO CENTER DROPSONDE SFC WIND AVAILABLE

[talkon]

09E GUILLERMO 150804 1200 19.3N 148.1W EPAC 60 989

[Yellow Evan]

WTPA44 PHFO 041504
TCDCP4

TROPICAL STORM GUILLERMO DISCUSSION NUMBER 23
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP092015
500 AM HST TUE AUG 04 2015

THE LATEST INFRARED SATELLITE PRESENTATION OF GUILLERMO HAS
DEGRADED IN APPEARANCE SINCE THE LAST ADVISORY...WITH WARMING CLOUD
TOPS AND A REDUCTION IN THE THUNDERSTORM ACTIVITY. THE LATEST
UW-CIMSS VERTICAL WIND SHEAR ANALYSIS INDICATES 25 KNOTS OF SHEAR
FROM 270 DEGREES...AND THIS IS LIKELY RESPONSIBLE FOR THE DEEP
CONVECTION HAVING DIFFICULTY MAINTAINING ITSELF NEAR THE LOW LEVEL
CIRCULATION CENTER OF GUILLERMO. DESPITE THE VERTICAL WIND SHEAR
PRESENT OVER THE SYSTEM...DVORAK CLASSIFICATIONS FROM PHFO AND JTWC
CONTINUE TO INDICATE T NUMBERS OF 3.5 OR 55 KNOTS...AND 3.0 OR 45
KNOTS FROM SAB. ADVANCED DVORAK TECHNIQUE (ADT) ALSO INDICATES A T
NUMBER OF 3.6 OR 57 KNOTS AS OF 04/1300Z. THE FINAL DECISION ON THE
INITIAL INTENSITY WAS ONCE AGAIN BASED ON DATA FROM THE U.S. 53RD
WEATHER RECONNAISSANCE AIRCRAFT WHICH SAMPLED THE INNER CORE OF
GUILLERMO EARLIER THIS MORNING. THE AIRCRAFT FOUND MAX FLIGHT LEVEL
WINDS OF 73 KNOTS...25 NM EAST OF THE CENTER OF CIRCULATION.
ADJUSTING THE FLIGHT LEVEL WINDS FROM THE 850 MB FLIGHT
LEVEL...YIELDS SURFACE WINDS OF 58 KNOTS. ADDITIONALLY...SFMR DATA
FROM THE AIRCRAFT INDICATED SURFACE WINDS OF AROUND 60 KNOTS IN THE
NE AND NW QUADRANTS OF THE STORM. AS A RESULT...THE INITIAL
INTENSITY OF GUILLERMO WAS KEPT JUST BELOW HURRICANE STRENGTH AT 60
KNOTS...UTILIZING A BLEND OF THE FLIGHT LEVEL AND SFMR WINDS FROM
THE AIRCRAFT.

THE INITIAL POSITION OF THE SYSTEM WAS BASED ON SATELLITE
EXTRAPOLATION FROM EARLIER CENTER FIX POSITIONS FROM THE
RECONNAISSANCE AIRCRAFT...WITH AN INITIAL MOTION TOWARD THE
NORTHWEST...OR 320 DEGREES AT 10 KNOTS. THE LATEST MODEL GUIDANCE
CHANGED VERY LITTLE FROM THE PREVIOUS ADVISORY PACKAGE...LIKELY
RESULTING FROM BETTER INITIALIZATION OF THE MOTION OF THE SYSTEM.
THE MOTION OF GUILLERMO APPEARS TO BE DRIVEN LARGELY BY THE
STRENGTH OF THE VERTICAL WIND SHEAR AS WELL AS A WEAKNESS IN THE
MID-UPPER LEVEL RIDGE WHICH EXTENDS FROM GUILLERMO OFF TO THE
NORTHWEST TO A LOCATION NEAR 30N157W. THE WEAKNESS IN THE RIDGE IN
COMBINATION WITH THE DEEP LAYER FLOW IS KEEPING GUILLERMO ON A TRACK
OFF TO THE NORTHWEST AT THE CURRENT TIME. AS A RESULT...THE OFFICIAL
FORECAST FOLLOWS A DIRECTION ON THE NORTH SIDE OF THE GUIDANCE
ENVELOPE THROUGH 24 HOURS WHICH ASSUMES MAINTENANCE OF DEEP
CONVECTION AND INTERACTION WITH THE WEAKNESS IN THE MID-UPPER LEVEL
RIDGE. BEYOND 24 HOURS AS WESTERLY WIND SHEAR IS FORECAST TO
INCREASE SIGNIFICANTLY OVER THE SYSTEM...CONVECTION SHOULD BECOME
INCREASINGLY SHALLOW...AND THE OFFICIAL FORECAST SHOWS A SHIFT
TOWARD THE WEST-NORTHWEST WHICH IS VERY CLOSE TO THE GFS AND TVCN
TRACKS AND SLIGHTLY TO THE NORTH OF THE PREVIOUS OFFICIAL FORECAST.
ON THIS TRACK...THE CLOSEST APPROACH OF GUILLERMO REMAINS WELL TO
THE NORTHEAST OF ALL THE HAWAIIAN ISLANDS. THE TROPICAL STORM WATCH
FOR THE BIG ISLAND AND MAUI COUNTY WAS MAINTAINED WITH THIS
ADVISORY PACKAGE...BUT IF THE MOTION OF THE SYSTEM CONTINUES...THE
WATCHES MAY BE CANCELLED LATER TODAY.

THE INTENSITY FORECAST FOR GUILLERMO IS A BLEND OF ICON AND HWRF
INTENSITY GUIDANCE ALONG WITH WEIGHT GIVEN TO THE PREVIOUS OFFICIAL
FORECAST. THE GLOBAL MODELS ARE SHOWING THE POTENTIAL FOR SOME
SLIGHT STRENGTHENING THROUGH THIS EVENING...AS SHEAR REMAINS NEARLY
UNCHANGED. VERTICAL WIND SHEAR IS THEN FORECAST TO FURTHER
STRENGTHEN OVER THE SYSTEM TONIGHT...AND THIS SHOULD LEAD TO STEADY
WEAKENING OF GUILLERMO THROUGH THE REMAINDER OF THE FORECAST. GIVEN
THE FAVORABLE SEA SURFACE TEMPERATURES OF AROUND 82 DEGREES
FAHRENHEIT BASED ON MODIS DATA FROM YESTERDAY AFTERNOON...IT IS NOT
OUT OF THE QUESTION THAT GUILLERMO COULD BECOME A HURRICANE OVER
THE NEXT 12 HOURS. THE OFFICIAL INTENSITY FORECAST WILL SHOW LITTLE
CHANGE IN STRENGTH HOWEVER OVER THE NEXT 12 HOURS...THEN SHOW SLOW
BUT STEADY WEAKENING THROUGH 120 HOURS.

ANOTHER RECONNAISSANCE AIRCRAFT MISSION INTO GUILLERMO IS SCHEDULED
FOR 18Z THIS MORNING. THE VALUABLE DATA TRANSMITTED IN REAL-TIME
FROM THESE MISSIONS WILL HELP US TO BETTER DETERMINE THE
LOCATION...INTENSITY AND SIZE OF THE TROPICAL STORM...ALONG WITH
ANY POTENTIAL IMPACTS TO THE HAWAIIAN ISLANDS.


FORECAST POSITIONS AND MAX WINDS

INIT 04/1500Z 19.7N 148.5W 60 KT 70 MPH
12H 05/0000Z 20.4N 149.6W 60 KT 70 MPH
24H 05/1200Z 21.4N 151.5W 50 KT 60 MPH
36H 06/0000Z 22.4N 153.4W 45 KT 50 MPH
48H 06/1200Z 23.1N 155.1W 40 KT 45 MPH
72H 07/1200Z 25.0N 159.0W 35 KT 40 MPH
96H 08/1200Z 26.5N 163.0W 30 KT 35 MPH
120H 09/1200Z 28.0N 167.0W 25 KT 30 MPH

$$
FORECASTER JELSEMA/BIRCHARD

[Yellow Evan]

WTPA34 PHFO 041756
TCPCP4

BULLETIN
TROPICAL STORM GUILLERMO INTERMEDIATE ADVISORY NUMBER 23A
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP092015
800 AM HST TUE AUG 04 2015

...GUILLERMO CONTINUES TO TRACK NORTHWESTWARD...


SUMMARY OF 800 AM HST...1800 UTC...INFORMATION
----------------------------------------------
LOCATION...19.9N 148.6W
ABOUT 420 MI...675 KM E OF HILO HAWAII
ABOUT 610 MI...980 KM E OF HONOLULU HAWAII
MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 10 MPH...16 KM/H
MINIMUM CENTRAL PRESSURE...989 MB...29.21 INCHES


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

NONE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

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

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...IN THIS CASE WITHIN 36 TO 48 HOURS.

INTERESTS ELSEWHERE IN THE MAIN HAWAIIAN ISLANDS SHOULD MONITOR THE
PROGRESS OF GUILLERMO.

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 800 AM HST...1800 UTC...THE CENTER OF TROPICAL STORM GUILLERMO
WAS LOCATED NEAR LATITUDE 19.9 NORTH...LONGITUDE 148.6 WEST.
GUILLERMO IS MOVING TOWARD THE NORTHWEST NEAR 10 MPH...16 KM/H...AND
THIS GENERAL MOTION IS EXPECTED TO CONTINUE TODAY...WITH A SHIFT
TOWARD THE WEST-NORTHWEST EXPECTED TONIGHT THROUGH THURSDAY
MORNING. ON THE FORECAST TRACK...THE CENTER OF GUILLERMO IS
EXPECTED TO PASS 215 MILES NORTHEAST OF HILO WEDNESDAY AFTERNOON
AND AROUND 165 MILES NORTH OF MAUI WEDNESDAY NIGHT.

MAXIMUM SUSTAINED WINDS ARE NEAR 70 MPH...110 KM/H...WITH HIGHER
GUSTS. LITTLE CHANGE IN STRENGTH IS EXPECTED TODAY...WITH SLOW AND
STEADY WEAKENING ANTICIPATED THEREAFTER.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 175 MILES...280 KM
FROM THE CENTER.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 989 MB...29.21 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...TROPICAL STORM CONDITIONS ARE POSSIBLE ON THE BIG ISLAND OF
HAWAII AND THE ISLANDS OF MAUI...MOLOKAI...LANAI AND KAHOOLAWE IN
MAUI COUNTY ON WEDNESDAY INTO WEDNESDAY NIGHT.

RAINFALL...TOTAL RAINFALL AMOUNTS OF 1 TO 3 INCHES...WITH ISOLATED
MAXIMUM AMOUNTS NEAR 7 INCHES MAINLY IN HIGHER TERRAIN...ARE
POSSIBLE IN THE WATCH AREA.

SURF...SWELLS ASSOCIATED WITH TROPICAL STORM GUILLERMO WILL PRODUCE
LARGE SURF ALONG EAST FACING SHORES OF THE MAIN HAWAIIAN ISLANDS
THROUGH MUCH OF THE WEEK.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 AM HST.

$$
FORECASTER KODAMA

[Alyono]

Question,

Is CPHC using the aircraft data at all? I ask because the plane found a 996mb pressure, yet they are saying it is 990mb

[cycloneye]

TROPICAL STORM GUILLERMO DISCUSSION NUMBER 24
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP092015
1100 AM HST TUE AUG 04 2015

AFTER A BRIEF INCREASE IN DEEP CONVECTION LAST NIGHT...THE
APPEARANCE OF GUILLERMO IN THE SATELLITE IMAGES HAS BECOME DEGRADED
ONCE AGAIN. THE SYSTEM IS VERY ASYMMETRIC WITH THE COLDEST CLOUD
TOPS MAINLY IN THE NORTHEAST QUADRANT AND SOME OF THE CIRRUS
REACHING CALIFORNIA. A USAF RESERVE WEATHER RECON MISSION THIS
MORNING REPORTED A MAXIMUM FLIGHT LEVEL WIND OF 65 KT AND A MAXIMUM
SFMR VALUE OF 55 KT IN THE NORTHEAST QUADRANT. THE INBOUND LEG FROM
THE NORTHWEST PICKED UP SFMR VALUES OF 65 AND 69 KT BUT THIS WAS
THROUGH A BURST OF DEEP CONVECTION AND IS CONSIDERED NOT
REPRESENTATIVE. BASED ON THE ADJUSTMENT TO THE FLIGHT LEVEL WINDS
AND THE VALID SFMR VALUES...THE INITIAL INTENSITY WILL BE MAINTAINED
AT 60 KT.

GUILLERMO HAS CONTINUED TO MOVE NORTHWEST THROUGH A BREAK IN THE
RIDGE ALOFT WITH THE INITIAL MOTION FOR THIS PACKAGE AT 310/09 KT.
THE RELIABLE OBJECTIVE AIDS HAS ONCE AGAIN SHIFTED NORTH A BIT FOR
THIS PACKAGE...AND THE FORECAST TRACK HAS BEEN NUDGED NORTH
SLIGHTLY FROM THE PREVIOUS FORECAST IN RESPONSE. THE CURRENT
FORECAST IS CLOSELY ALIGNED WITH THE ECMWF FORECAST THROUGH 48
HOURS THEN SOUTH OF MOST OF THE DYNAMICAL GUIDANCE BEYOND THAT TIME
FRAME. ON THE FORECAST TRACK...GUILLERMO IS FORECAST TO REMAIN WELL
NORTHEAST OF THE MAIN HAWAIIAN ISLANDS AT ITS CLOSEST POINT OF
APPROACH. IF THIS MOTION CONTINUES...AND THERE IS NO
SIGNIFICANT DEVIATION TO THE LEFT OF THE FORECAST TRACK...THE
TROPICAL STORM WATCH FOR THE BIG ISLAND AND MAUI COUNTY MAY BE
CANCELED LATER TODAY OR TONIGHT.

THE CIMSS ANALYSIS AT 1800 UTC SHOWED OVER 26 KT OF VERTICAL SHEAR
IMPACTING GUILLERMO. THE SYSTEM IS MOVING INTO AN AREA OF
INCREASING VERTICAL SHEAR. IT IS ALSO MOVING TOWARD A DRIER
AIRMASS. THESE FACTORS SHOULD STEADILY WEAKEN GUILLERMO EVEN THOUGH
SEA SURFACE TEMPERATURES ARE ADEQUATE. SHIPS GUIDANCE SHOWS A SHARP
WEAKENING WITH DISSIPATION BY 72 HOURS. HWRF MAINTAINS THE SYSTEM
NEAR 50 KT FOLLOWED BY A SHARPER WEAKENING TREND. THE FORECAST
FOLLOWS THE IVCN CONSENSUS WITH GUILLERMO STEADILY WEAKENING TO
A TROPICAL DEPRESSION AFTER DAY 3.


FORECAST POSITIONS AND MAX WINDS

INIT 04/2100Z 20.2N 149.0W 60 KT 70 MPH
12H 05/0600Z 21.0N 150.2W 55 KT 65 MPH
24H 05/1800Z 22.0N 152.0W 50 KT 60 MPH
36H 06/0600Z 23.0N 154.0W 45 KT 50 MPH
48H 06/1800Z 24.0N 155.7W 40 KT 45 MPH
72H 07/1800Z 25.6N 159.4W 35 KT 40 MPH
96H 08/1800Z 27.0N 163.5W 30 KT 35 MPH
120H 09/1800Z 28.5N 167.5W 25 KT 30 MPH

$$
FORECASTER KODAMA