WPAC: WASHI - Tropical Storm 27W

[euro6208]

3.4N-154.2E Southeast of Guam.

small system. very organized for a december invest...

[phwxenthusiast]

cyclonic turning pretty evident on this mwi... imho, with the weak-moderate shear and warm SSTs, 95W definitely has a chance of becoming something in the next few days...

[euro6208]

really favorable

[cycloneye]

Surely for being December,the WPAC has been active. Doesn't look too bad. Rob,what do you think of the future of this disturbance?

[euro6208]

vorticity increasing...

[cycloneye]

Upgraded to medium by JTWC.

AN AREA OF CONVECTION HAS PERSISTED NEAR 5.7N 148.6E,
APPROXIMATELY 510 NM SOUTH-SOUTHEAST OF GUAM. ANIMATED INFRARED
SATELLITE IMAGERY SHOWS DEEP CONVECTION HAS PERSISTED OVER A
DEVELOPING LOW-LEVEL CIRCULATION CENTER (LLCC). A RECENT 121805Z
SSMIS 37H IMAGE SHOWS WEAK BANDING CONVECTION BEGINNING TO DEVELOP
ALONG THE WESTERN AND NORTHERN PERIPHERY OF THE LLCC. THE LLCC
REMAINS SMALL IN OVERALL EXTENT AND IS TRACKING WESTWARD ALONG THE
SOUTHERN BOUNDARY OF A SUBTROPICAL RIDGE. UPPER LEVEL ANALYSIS
INDICATES THE LLCC IS LOCATED UNDER A REGION OF SPEED DIVERGENCE
ALOFT AND SLIGHTLY EQUATORWARD OF A WEAK UPPER-LEVEL LOW, BOTH OF
WHICH ARE AIDING OUTFLOW. VERTICAL WIND SHEAR IS MODERATE AT ABOUT
15 KNOTS. OBSERVATIONS IN THE VICINITY OF THE LLCC INDICATE SURFACE
PRESSURES NEAR 1007 MB. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1007 MB. BASED ON THE PERSISTENT CONVECTION, MODERATE
VERTICAL WIND SHEAR, AND IMPROVING LOW-LEVEL ORGANIZATION, THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS UPGRADED TO MEDIUM.

[phwxenthusiast]

looking better today with that circulation and convection... more interested with this than 26W tbh lol

[cycloneye]

Looking very good.

[cycloneye]

Tropical Cyclone Formation Alert

FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
155 NM EITHER SIDE OF A LINE FROM 5.9N 147.2E TO 7.1N 140.9E WITHIN
THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF
NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME. WINDS IN THE AREA
ARE ESTIMATED TO BE 15 TO 20 KNOTS. METSAT IMAGERY AT 122330Z
INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 6.0N 146.7E. THE
SYSTEM IS MOVING WESTWARD AT 22 KNOTS.
REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 5.7N
148.6E IS NOW LOCATED NEAR 6.0N 146.7E, APPROXIMATELY 450 NM SOUTH-
SOUTHEAST OF GUAM. ANIMATED INFRARED AND MULTISPECTRAL SATELLITE
IMAGERY SHOWS DEEP CONVECTION CONTINUING TO DEVELOP OVER A SMALL LOW
LEVEL CIRCULATION CENTER (LLCC) WITH A RECENT 122001Z WINDSAT 37H
IMAGE INDICATING DEVELOPMENT OF CONVECTIVE BANDING. THE LLCC
CONTINUES TO TRACK WESTWARD UNDER THE INFLUENCE OF A SUBTROPICAL
RIDGE LOCATED TO THE NORTH. UPPER LEVEL ANALYSIS SUGGESTS THE
RAPID WESTWARD TRACK SPEED IS KEEPING LOW VERTICAL WIND SHEAR LOW
DESPITE MODERATELY EASTERLY FLOW IN THE UPPER-LEVELS. THIS LOW
VERTICAL WIND SHEAR IS ALLOWING CONVECTION TO DEVELOP AND PERSIST.
ADDITIONALLY, SPEED DIVERGENCE AND A WEAK UPPER-LEVEL LOW TO THE
NORTHWEST ARE INCREASING POLEWARD OUTFLOW. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1007 MB. BASED ON THE PERSISTENT CONVECTION,
LOW VERTICAL WIND SHEAR, AND IMPROVING LOW-LEVEL ORGANIZATION, THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS UPGRADED TO HIGH.

[Typhoon Hunter]

First post here for a while! It looked like 2011 was going to have the earliest end to a typhoon season since records began but 95W may well scupper that record. It's looking pretty juicy right now.

Models not doing a huge amount with it right now but consensus at moment looks like a soaker for Mindanao.

[euro6208]

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TIYAN GU
1221 PM CHST TUE DEC 13 2011

PMZ161-171-140200-
KOROR PALAU-YAP-
1221 PM CHST TUE DEC 13 2011

...TROPICAL DISTURBANCE MOVING WEST ACROSS FAR EASTERN YAP STATE...

A SLOWLY DEVELOPING CIRCULATION WAS CENTERED ABOUT 375 MILES WEST OF
CHUUK NEAR 5N147E AT 1000 AM CHST. THE JOINT TYPHOON WARNING CENTER
HAS UPGRADED THIS DISTURBANCE TO MEDIUM FOR DEVELOPMENT POTENTIAL
OVER THE NEXT 24 HOURS AS IT MOVES WEST AT ABOUT 15 MPH.

NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS ARE CURRENTLY MOVING
ACROSS THE ISLANDS OF SATAWAL...FARAULEP AND WOLEAI IN EASTERN YAP
STATE...WHERE 2 TO 4 INCHES OF RAIN MAY FALL THROUGH TONIGHT.

AS THE DISTURBANCE MOVES WESTWARD...NUMEROUS SHOWERS AND ISOLATED
THUNDERSTORMS WILL MOVE ACROSS ULITHI...FAIS AND THE MAIN ISLANDS OF
YAP ON WEDNESDAY AND WEDNESDAY NIGHT...AND ACROSS THE REPUBLIC OF
PALAU WEDNESDAY NIGHT AND THURSDAY. RAIN WILL LIKELY BE HEAVY AT
TIMES...WITH 3 TO 5 INCHES POSSIBLE THROUGH THURSDAY. WINDS MAY
ALSO INCREASE WEDNESDAY AND THURSDAY...WITH GUSTS OF 30 TO 35 MPH
POSSIBLE NEAR SHOWERS AND THUNDERSTORMS.

PEOPLE PLANNING INTER-ISLAND TRAVEL BY BOAT SHOULD MONITOR THIS
SITUATION...AND IF POSSIBLE...CHECK WITH THEIR WEATHER SERVICE
OFFICE BEFORE ATTEMPTING SUCH TRAVEL. KEEP ALERT FOR ANY LATER
STATEMENTS FROM LOCAL OFFICIALS OR THE NATIONAL WEATHER SERVICE.

now south of guam...


A. TROPICAL DISTURBANCE (95W)

B. 13/0230Z

C. 5.6N

D. 146.0E

E. THREE/MTSAT

F. T2.0/2.0/D1.0/12HRS

G. IR/EIR/VIS

H. REMARKS...95W APPEARS TO BE DEVELOPING RAPIDLY AS CONVECTION HAS
INCREASED IN ORGANIZATION AND INTENSITY PAST 6-12 HOURS. CONVECTIVE BAND
WRAPS AROUND NORTHERN SEMICIRCLE WITH SMALL CDO LIKE FEATURE DEVELOPING
OVER APPARENT LLCC. 4 TENTHS BANDING GIVES DT=2.5. MET=1.5. PT=2.0. FT
IS BASED ON CONSTRAINTS.


a monster in the making for the philippines???

[Typhoon Hunter]

Not every storm develops into a monster...

Models doing little with it at the moment so too early to speculate.

[Crostorm]

[Typhoon Hunter]

Upgraded to 27W by JTWC, they're expecting a typhoon out of this one tracking into northern Mindano via Palau...interesting!

[cycloneye]

Upgraded to 27W by JTWC, they're expecting a typhoon out of this one tracking into northern Mindano via Palau...interesting!

And here is the first warning. Has JMA also upgraded?


MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE WARNING//
REF/A/NAVMARFCSTCEN PEARL HARBOR HI/JTWC/130221Z DEC 11//
AMPN/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. TROPICAL DEPRESSION 27W (TWENTYSEVEN) WARNING NR 001
02 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
130600Z --- NEAR 6.0N 145.1E
MOVEMENT PAST SIX HOURS - 270 DEGREES AT 16 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 6.0N 145.1E
---
FORECASTS:
12 HRS, VALID AT:
131800Z --- 6.2N 141.3E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 275 DEG/ 17 KTS
---
24 HRS, VALID AT:
140600Z --- 6.5N 137.9E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 280 DEG/ 14 KTS
---
36 HRS, VALID AT:
141800Z --- 6.9N 135.1E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 280 DEG/ 15 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
150600Z --- 7.3N 132.1E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 285 DEG/ 14 KTS
---
72 HRS, VALID AT:
160600Z --- 8.8N 126.8E
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 285 DEG/ 12 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
170600Z --- 10.2N 122.0E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 285 DEG/ 13 KTS
---
120 HRS, VALID AT:
180600Z --- 11.6N 116.8E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
130900Z POSITION NEAR 6.0N 144.1E.
TROPICAL DEPRESSION (TD) 27W, LOCATED APPROXIMATELY 430 NM SOUTH OF
ANDERSEN AIR FORCE BASE, GUAM, HAS TRACKED WESTWARD AT 16 KNOTS OVER
THE PAST SIX HOURS. RECENT ANIMATED MULTISPECTRAL SATELLITE IMAGERY
(MSI) DEPICTS DEEP CONVECTION CONTINUING TO DEVELOP OVER THE LOWER-
LEVEL CIRCULATION CENTER (LLCC). A 122356Z AMSU IMAGE REVEALS THAT
THE DEEP CONVECTION IS SOMEWHAT FRAGMENTED WITH MULTIPLE RAINBANDS
WRAPPING IN TOWARDS THE LLCC. THE INITIAL POSITION IS BASED ON THE
PGTW CENTER FIX AND THE MSI WITH FAIR CONFIDENCE. THE INITIAL
INTENSITY IS BASED ON DVORAK ESTIMATES RANGING FROM 25-30 KNOTS FROM
PGTW/KNES, AND RJTD RESPECTIVELY. UPPER-LEVEL ANALYSIS INDICATES
THAT TD 27W IS CURRENTLY UNDER A NEAR EQUATORIAL RIDGE AXIS IN AN
AREA OF LOW (05-10 KNOT) VERTICAL WIND SHEAR (VWS) WITH EXCELLENT
DIVERGENCE ALOFT. RECENT ANIMATED WATER VAPOR IMAGERY SHOWS THAT THE
SYSTEM HAS A SLIGHTLY ENHANCED POLEWARD OUTFLOW CHANNEL INTO A WEAK
UPPER-LEVEL LOW LOCATED TO THE NORTH-NORTHWEST OF THE LLCC. TD 27W
IS CURRENTLY BEING STEERED WESTWARDS BY THE SOUTHERN PERIPHERY OF A
LOW- TO MID-LEVEL SUBTROPICAL RIDGE. TD 27W WILL CONTINUE TO
GENERALLY TRACK WESTWARDS AND GRADUALLY INTENSIFY UNDER FAVORABLE
ALONG TRACK CONDITIONS. SEA SURFACE TEMPERATURES WILL REMAIN NEAR 29-
30 DEGREES CELSIUS AND THE UPPER-LEVEL ENVIRONMENT SHOULD REMAIN
FAVORABLE AS VWS SHOULD STAY BELOW 20 KNOTS. BY TAU 72, TD 27W
SHOULD BEGIN TO MAKE LANDFALL OVER THE SOUTHERN PHILIPPINES AS A
SIGNIFICANT TROPICAL STORM. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
130600Z IS 8 FEET. NEXT WARNINGS AT 131500Z, 132100Z, 140300Z AND
140900Z. THIS WARNING SUPERSEDES AND CANCELS REF A, NAVMARFCSTCEN
130221Z DEC 11 TROPICAL CYCLONE FORMATION ALERT (WTPN21 PGTW
130230 ). REFER TO TROPICAL DEPRESSION 26W (TWENTYSIX) WARNINGS
(WTPN31 PGTW) FOR SIX-HOURLY UPDATES.//
NNNN

[phwxenthusiast]

no "warnings" yet from JMA, but it's there...

[dexterlabio]

The last time I checked on the Pacific weather was yesterday morning, and I saw typical year-end easterly waves and surge of northeast monsoon. Nothing special for a tropical cyclogenesis...then poof! A wild tropical system has appeared.

Though Euro's still not picking up on this. Not even recognizing a well-defined low pressure system in their latest model runs. Well things happened quickly and of course you won't expect the models to pick up on it right ahead, unless they are foreseeing sudden dissipation as fast as it developed.

And I am taking back what I said before, typhoon season's not really done yet.

[Chacor]

6z:

TROPICAL DEPRESSION 1004 HPA AT 06N 145E WEST 10 KT.

[Chacor]

WTPQ20 RJTD 131200
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 131200UTC 06.2N 143.1E FAIR
MOVE W 18KT
PRES 1006HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 141200UTC 07.8N 135.0E 120NM 70%
MOVE W 20KT
PRES 998HPA
MXWD 035KT
GUST 050KT =

[dexterlabio]

This is getting chunkier by the minute, thick cold convection over the center. With a good start like this, it will be a waste if it would end up dissipating quickly. Still, rapid consolidation seems imminent. It just feels unusual to have a significant tropical cyclone this late especially if it would be a threat to land. Utor was one but December storms like this are rare. Not sure if this system will be like one. Hopefully not, Christmas is just a few days away.