WPAC: WIPHA - Post-Tropical - Discussion

[mrbagyo]

8:00 AM update (0000 UTC)

From TYboard


SLP at the buoy has plunged to 968.9 hPa

[StormWeather]

8:00 AM update (0000 UTC)

From TYboard


SLP at the buoy has plunged to 968.9 hPa
https://s14.gifyu.com/images/bKjfu.jpg

This thing has Category 2 pressures as a tropical storm. That’s absurd.

[sasha_B]

09W WIPHA 250720 0000 21.6N 114.6E WPAC 60 970

Looks like JTWC went with 60 kts / 970 hPa for the 0z Best Track point. (CMA has 70 / 970, and JMA 55 / 975.)

[StormWeather]

09W WIPHA 250720 0000 21.6N 114.6E WPAC 60 970

Looks like JTWC went with 60 kts / 970 hPa for the 0z Best Track point. (CMA has 70 / 970, and JMA 55 / 975.)

When was the last time that a tropical storm had this absurdly low of a pressure?

[cycloneye]

They updated up to 65kt.

09W WIPHA 250720 0000 21.6N 114.6E WPAC 65 970

[mrbagyo]

HongKong is now under Signal No. 10

[mrbagyo]

[cycloneye]

[Hurricane2022]

The title of this thread needs to be corrected back to "Severe Tropical Storm", because JMA still hasn't upgraded it (and they probably won't, due to their inexplicable hatred of typhoons that pass through or form in the South China Sea)

[cycloneye]

The title of this thread needs to be corrected back to "Severe Tropical Storm", because JMA still hasn't upgraded it (and they probably won't, due to their inexplicable hatred of typhoons that pass through or form in the South China Sea)

Edited the title but JMA is very conservative with the data available from dvorak etc.

[mrbagyo]

All ground data suggest this is a legit typhoon

[mrbagyo]

[cycloneye]

[Hayabusa]

00z COTC intensifying over land

[cycloneye]

SUMMARY:
INITIAL POSITION: 21.7N 111.7E
INITIAL INTENSITY: 60 KTS
GEOGRAPHIC REFERENCE: 327 NM EAST OF HANOI, VIETNAM
MOVEMENT PAST 6 HOURS: WESTWARD AT 14 KTS
SIGNIFICANT WAVE HEIGHT: 24 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY REVEALS A FULLY
OBSCURED LOW-LEVEL CIRCULATION CENTER (LLCC) ASSOCIATED WITH
TROPICAL STORM (TS) 09W (WIPHA). THE INITIAL POSITION IS CURRENTLY
ASSESSED TO BE OVER LAND WITH MEDIUM CONFIDENCE. RADAR IMAGERY, AS
WELL AS A 201046Z 37 GHZ F17 SSMIS MICROWAVE IMAGE SUITE OFFER SOME
ASSISTANCE IN ESTIMATING THE POSITION THROUGH EXTRAPOLATION. THE
INITIAL INTENSITY OF 60 KTS IS ASSESSED WITH MEDIUM CONFIDENCE
BASED ON A T3.5 DVORAK ESTIMATE FROM RJTD, OBJECTIVE ESTIMATES
LISTED BELOW, AND VISUAL DETERIORATION OF CONVECTIVE BANDING AND
STRUCTURE OF THE SYSTEM DUE TO FRICTIONAL EFFECTS OF LAND INTERACTION.
ENVIRONMENTAL CONDITIONS REMAIN FAVORABLE FOR INTENSIFICATION, IN CASE
TS 09W REEMERGES OVER WATER PRIOR TO CROSSING THE LEIZHOU PENINSULA.
WARM SEA SURFACE TEMPERATURES (SST) OF 29-30 C, HIGH ATMOSPHERIC
COLUMN MOISTURE CONTENT AND MODERATE EQUATORWARD OUTFLOW ALOFT ARE
OFFSET ONLY BY PERSISTENT LOW TO MODERATE (15-20 KTS) NORTHEASTERLY
VERTICAL WIND SHEAR (VWS).

[cycloneye]

Still STS from JMA.

[sasha_B]

HAFS-A and HWRF continue to depict rapid reintensification once it's back over water on their 12z outputs, with the former taking it back to minimal typhoon strength and the latter having it reach an even higher peak (<960 hPa) before landfall in Vietnam. The CMA explicitly forecasts a second landfall as a typhoon, while the JMA and JTWC forecasts show limited reintensification to STS strength, 55～60 kts.

[cycloneye]

INITIAL POSITION: 21.6N 110.8E
INITIAL INTENSITY: 50 KTS
GEOGRAPHIC REFERENCE: 194 NM WEST-SOUTHWEST OF HONG KONG
MOVEMENT PAST 6 HOURS: WESTWARD AT 10 KTS
SIGNIFICANT WAVE HEIGHT: XX FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS TROPICAL
STORM (TS) 09W OVER LAND, CURRENTLY TRACKING JUST NORTH OF ZHANJIANG,
CHINA. THE LIKELY CENTER IS BECOMING INCREASINGLY WELL-DEFINED AS THE
SYSTEM CONTINUES WESTWARD OVER RELATIVELY FLAT TERRAIN, DECREASING THE
FRICTIONAL EFFECTS, WHICH DISRUPTED THE VORTEX TO A HIGHER DEGREE.
ANIMATED RADAR DATA INDICATES THE LOW LEVEL CIRCULATION CENTER (LLCC)
IS STILL A BIT DISORGANIZED; HOWEVER THE OUTER RAIN BANDS ARE BECOMING
STEADILY MORE DEFINED AND WRAPPING INTO THE CENTER. ANIMATED WATER
VAPOR IMAGERY INDICATES STRONG EQUATORWARD OUTFLOW OVER THE GULF OF
TONKIN, WHILE THE CIRA DERIVED MOTION WINDS PRODUCT SHOWS UPPER-LEVEL
WINDS STREAMING SOUTHWESTWARD AT NEAR 40 KNOTS, PROVIDING AMPLE
OUTFLOW TO SUPPORT CONVECTIVE DEVELOPMENT ONCE THE SYSTEM GETS BACK
OVER WATER. THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE
BASED ON THE RADAR DATA. THE INITIAL INTENSITY IS ASSESSED WITH LOW
CONFIDENCE DUE TO THE LACK OF RELIABLE INTENSITY
ESTIMATES OVER LAND, THOUGH THE DPRINT AND RJTD FIX ARE GENERALLY
CONSISTENT WITH THE ASSESSED INTENSITY. THE ENVIRONMENT IS, OVERALL,
FAVORABLE FOR DEVELOPMENT ONCE THE SYSTEM REACHES THE WATER AGAIN.
SHEAR REMAINS RELATIVELY HIGH; HOWEVER THE SHEAR VECTOR IS IN PHASE
WITH THE STORM MOTION, AND THE OUTFLOW IS STRONG, WHICH WILL PARTIALLY
COUNTERACT THE SHEAR.

[Ulf]

Still STS from JMA.

Is JMA ever going to upgrade this to typhoon status?

Cannot help but be a bit annoyed that they keep it as STS despite the pressure and the data on the ground from Hong Kong.

[cycloneye]

Emerging to the Gulf of Tonkin, where it could get up in intensity again.