Invest

Western Pacific Invest · WP932026

22.0°N, 138.8°E

Moving Stationary

Max Winds

25 mph

Pressure

1000 mb

Forecast Points

Summary

Invest 93W currently has maximum sustained winds of about 25 mph and is moving east-northeast at around 4 knots. The system is located about 245 nautical miles southwest of Iwo To, and a compact low-level circulation is present with bursts of thunderstorms near the center. The Joint Typhoon Warning Center says formation of a significant tropical cyclone is possible within the next 12 to 24 hours, and the potential for development within the next 24 hours is high. Environmental conditions are favorable, including low vertical wind shear, warm sea-surface temperatures, and good upper-level outflow. Model guidance suggests the system will generally move north-northeast. Some model solutions do not develop it into a tropical cyclone, while ensemble guidance shows it could quickly reach tropical depression strength but only for a short time over the next 24 hours; numbered tropical cyclone warnings have not been issued at this time.

Key messages

Development is possible in the next 12 to 24 hours, with high potential for a significant tropical cyclone within 24 hours.
Invest 93W is about 245 nautical miles southwest of Iwo To and is moving east-northeast slowly.
Forecast guidance generally takes it north-northeast, with some solutions showing only brief tropical depression strength.

Satellite Imagery (IR)

CIRA/RAMMB · 13 Aug 08:50 UTC

JTWC Warning 13 Aug 00:00 UTC

WTPN21 PGTW 130600
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 93W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
140 NM EITHER SIDE OF A LINE FROM 21.8N 137.9E TO 23.6N 144.4E
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 17 TO 22 KNOTS. METSAT
IMAGERY AT 130000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 21.9N 138.1E. THE SYSTEM IS MOVING EAST-NORTHEASTWARD AT 04
KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 93W) PREVIOUSLY LOCATED
NEAR 21.7N 137.7E IS NOW LOCATED NEAR 21.9N 138.1E, APPROXIMATELY 245 NM 
SOUTHWEST OF IWO TO. ANIMATED MULTISPECTRAL IMAGERY (MSI) DEPICTS A VERY 
COMPACT LOW-LEVEL CIRCULATION CENTER (LLCC) WITH FLARING CONVECTION OVER 
THE CIRCULATION. A 130102Z ASCAT-C PASS REVEALS 20-25 KNOTS WINDS AROUND 
THE BULK OF THE CIRCULATION, WITH SOME HIGHER WINDS FURTHER TO THE SOUTH 
IN THE MONSOONAL SOUTHWESTERLIES. ENVIRONMENTAL ANALYSIS REVEALS 
FAVORABLE CONDITIONS FOR DEVELOPMENT WITH LOW VERTICAL WIND SHEAR (10 TO 
15KTS), WARM SEA SURFACE TEMPERATURES (29 TO 30 C), AND GOOD POLEWARD 
UPPER-LEVEL OUTFLOW. DETERMINISTIC MODELS DEPICT A CIRCULATION THAT 
MOVES GENERALLY NORTH-NORTHEAST BUT DOES NOT DEVELOP  INTO A TROPICAL 
CYCLONE. ENSEMBLE MODELS SHOW THE RAPID ATTAINMENT, BUT SHORT-LIVED 
DURATION, OF TROPICAL DEPRESSION STRENGTH AND A SIMILAR TRACK TO THE 
DETERMINISTIC MODELS OVER THE NEXT 24 HOURS. MAXIMUM SUSTAINED SURFACE 
WINDS ARE ESTIMATED AT 17 TO 22 KNOTS. MINIMUM SEA LEVEL PRESSURE IS 
ESTIMATED TO BE NEAR 1006 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A 
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 
140600Z.//
NNNN

Products not available for West Pacific storms

NEXRAD radar — no radar coverage over the open West Pacific.
Storm-surge inundation — no public storm-surge model for this basin.
Wind-speed probabilities — JTWC does not publish them.
Watches and warnings — issued by local agencies (PAGASA, JMA, CWA), not JTWC.
Reconnaissance aircraft — no routine aircraft reconnaissance in the West Pacific.
Rapid-intensification and shear diagnostics — SHIPS-based guidance is not published for this basin.

These are data-availability limits for the West Pacific basin, not omissions.

Source: U.S. Navy/Air Force Joint Typhoon Warning Center (JTWC), via the UCAR Tropical Cyclone Guidance Project. JTWC data is in the public domain. · Updated 2026-08-13 08:25 UTC · JMA analysis: Source: Japan Meteorological Agency (10-minute average winds). Satellite imagery: CIRA/RAMMB.