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Active Tropical Systems & Formation Outlook
A whole-basin summary of all active tropical cyclones and the NHC
Tropical Weather Outlook, generated with the
tropycal
package. Select a storm below for its official forecast and model guidance.
HAFS and GEFS guidance is only available for storms in the US/NHC domain (Atlantic & East/Central Pacific). For this system, the basin summary and best-track position are shown.
WDPN31 PGTW 090900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 12W (DOLPHIN) WARNING NR 054//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 28.1N 121.9E
INITIAL INTENSITY: 75 KTS
GEOGRAPHIC REFERENCE: 181 NM NORTH OF TAIPEI, TAIWAN
MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 12 KTS
SIGNIFICANT WAVE HEIGHT: 30 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS AN EXPANSIVE
SYSTEM WITH OUTER RAINBANDS EXTENDING FROM TAIWAN TO SHANGHAI AND A
VERY COMPACT, CLOUD-FILLED EYE EMBEDDED WITHIN A MUCH SMALLER INNER
CORE OF DEEP CONVECTION. ANIMATED RADAR DATA SHOWS THE EYE BECOMING
MORE RAGGED AND LESS-DEFINED AS IT APPROACHES THE COAST OF ZHEJIANG
PROVINCE, CHINA BUT THE WESTERN EYEWALL IN PARTICULAR IS
WELL-DEFINED AND NOW BRUSHING THE COAST NEAR SHITANGZHEN, CHINA.
SURFACE OBSERVATIONS FROM DACHEN DAO TO THE NORTH REPORTED
EAST-NORTHEAST WINDS OF 45 KNOTS AND AN MSLP READING OF 965 MB AT
0600Z. THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE BASED
ON THE RADAR DATA AND THE EYE FEATURE IN THE MSI. THE INITIAL
INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE. SUBJECTIVE DVORAK
CURRENT INTENSITY ESTIMATES CONTINUE TO VASTLY OUTPERFORM THE
MAJORITY OF THE OBJECTIVE INTENSITY ESTIMATES (EXCEPT THE SATCON),
WHICH ARE STRUGGLING WITH THE COMPLEX STRUCTURE OF THE SYSTEM. THE
ENVIRONMENT REMAINS FAVORABLE, BUT THE IMMINENT LANDFALL MEANS THE
SYSTEM WILL NOT HAVE TIME TO TAKE ADVANTAGE OF THE FAVORABLE
CONDITIONS.
INITIAL WIND RADII BASIS: PERSISTENCE
CURRENT STEERING MECHANISM: SOUTHERN PERIPHERY OF AN EXTENSION OF
THE SUBTROPICAL RIDGE (STR) CENTERED OVER SOUTHERN JAPAN AND
EXTENDING NORTHWEST TO THE SHANDONG PENINSULA.
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T4.5 - 77 KTS
RJTD: T5.0 - 90 KTS
RCTP: T4.0 - 65 KTS
KNES: T5.0 - 90 KTS
CIMSS SATCON: 80 KTS AT 090600Z
CIMSS ADT: 51 KTS AT 090600Z
CIMSS AIDT: 66 KTS AT 090600Z
CIMSS D-MINT: 60 KTS AT 090427Z
CIMSS D-PRINT: 63 KTS AT 090530Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 10-15 KTS
SST: 29-30 CELSIUS
OUTFLOW: STRONG RADIAL
OTHER FACTORS: PROXIMITY TO LAND.
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: MEDIUM
INITIAL WIND RADII: MEDIUM
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.
FORECAST DISCUSSION: TYPHOON (TY) 12W WILL MAKE LANDFALL ALONG THE
SOUTHEASTERN CHINESE COAST, SOUTH OF THE CITY OF TAIZHOU WITHIN THE
NEXT FEW HOURS. THE WESTERN EYEWALL IS ALREADY BRUSHING THE
COASTLINE AND THE LATEST RADAR ANIMATIONS SUGGEST THE SYSTEM MAY
ATTEMPT ONE MORE TROCHOIDAL WOBBLE SOUTHWESTWARD BEFORE CROSSING
THE COAST. OVERALL, THE SYSTEM WILL TRACK WESTWARD ALONG THE SOUTHERN
FLANK OF THE STR BUILDING TO THE NORTH FOR THE NEXT 12 HOURS, THEN
TURN NORTHWESTWARD AS THE RIDGE RECEDES SLIGHTLY EASTWARD. NO
CHANGE IN INTENSITY IS EXPECTED IN THE SHORT TIME PRIOR TO
LANDFALL. AFTER LANDFALL, THE SYSTEM WILL RAPIDLY WEAKEN AND
DISSIPATE OVER EAST-CENTRAL CHINA WITHIN 48 HOURS.
MODEL DISCUSSION: TRACK GUIDANCE IS IN STRONG AGREEMENT, WITH
MINIMAL CROSS-TRACK SPREAD THROUGH THE FORECAST PERIOD, LENDING
HIGH CONFIDENCE TO THE JTWC FORECAST TRACK, WHICH IS PLACED NEAR
THE AI CONSENSUS MEAN THROUGH THE FORECAST PERIOD. INTENSITY
GUIDANCE IS ALSO IN STRONG AGREEMENT DEPICTING RAPID WEAKENING
THROUGH THE FORECAST PERIOD, LENDING HIGH CONFIDENCE TO THE JTWC
INTENSITY FORECAST.
FORECAST CONFIDENCE:
TRACK 00-72 HR: HIGH
INTENSITY 00-72 HR: HIGH//
NNNN
HAFS and GEFS guidance is only available for storms in the US/NHC domain (Atlantic & East/Central Pacific). For this system, the basin summary and best-track position are shown.
WDPN32 PGTW 100300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 13W (PEILOU) WARNING NR
013//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 20.5N 148.3E
INITIAL INTENSITY: 40 KTS
GEOGRAPHIC REFERENCE: 452 NM NORTH-NORTHEAST OF ANDERSEN AFB
MOVEMENT PAST 6 HOURS: EASTWARD AT 24 KTS
SIGNIFICANT WAVE HEIGHT: 15 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TROPICAL
STORM (TS) 13W (PEILOU) AS A SMALL SYSTEM WITH PERSISTENT CONVECTION
JUST NORTHEAST OF THE ASSESSED LOW LEVEL CIRCULATION CENTER (LLCC) AS
WELL AS A STRONG CONVECTIVE BAND CURVING OFF TO THE SOUTHWEST,
SPANNING ACROSS THE NORTHERN MARIANAS. ENVIRONMENTAL ANALYSIS REVEALS
FAVORABLE CONDITIONS OF LOW (5-10 KTS) VERTICAL WIND SHEAR, WARM (29-
30 C) SEA SURFACE TEMPERATURES, AND AN UPPER-LEVEL TROUGH POSITIONED
TO THE NORTHWEST OF TS 13W AIDING IN THE UPPER LEVEL OUTFLOW,
OBSERVABLE IN MSI. THE INITIAL POSITION IS ASSESSED WITH MEDIUM
CONFIDENCE BASED ON THE PARTIALLY EXPOSED WESTERN FLANK OF THE LLCC IN
MSI. THE INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON
AGREEMENT BETWEEN AGENCY DVORAK FIXES AND CIMSS OBJECTIVE ESTIMATES
LISTED BELOW.
INITIAL WIND RADII BASIS: PERSISTENCE
CURRENT STEERING MECHANISM: LOW-LEVEL MONSOONAL FLOW AND EASTERN
EXTENSION OF A NEAR EQUATORIAL RIDGE (NER) CENTERED TO THE
SOUTHWEST
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.5 - 35 KTS
RJTD: T2.0 - 30 KTS
RCTP: T2.5 - 35 KTS
CIMSS ADT: 43 KTS AT 092330Z
CIMSS AIDT: 37 KTS AT 092330Z
CIMSS D-PRINT: 31 KTS AT 092330Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 5-10 KTS
SST: 29-30 CELSIUS
OUTFLOW: STRONG POLEWARD
OTHER FACTORS: UPPER-LEVEL TROUGH POSITIONED TO THE NORTHWEST
ANALYSIS CONFIDENCE:
INITIAL POSITION: MEDIUM
INITIAL INTENSITY: MEDIUM
INITIAL WIND RADII: MEDIUM
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.
FORECAST DISCUSSION: TS 13W IS FORECAST TO CONTINUE ON AN EAST-
NORTHEASTWARD TRACK OUT TO TAU 12 BEFORE TAKING A MORE POLEWARD TURN
AS IT REMAINS UNDER THE STEERING INFLUENCE OF THE STRONG LOW-LEVEL
MONSOONAL FLOW AND, TO A LESSER EXTENT, THE EASTERN EXTENSION OF A
NEAR EQUATORIAL RIDGE (NER) CENTERED TO THE SOUTHWEST, WITH BOTH
CONTRIBUTING TO THE SAME RESULTANT TRACK. REGARDING INTENSITY, TS 13W
IS CURRENTLY IN AN AREA OF INCREASED OUTFLOW ALOFT THANKS TO THE
UPPER-LEVEL TROUGH POSITIONED TO THE NORTHWEST, HOWEVER THIS TROUGH IS
EXPECTED TO PASS OVER TS 13W AND RETREAT BY TAU 36 AT WHICH POINT THE
SYSTEM IS EXPECTED TO EXPERIENCE INCREASED NORTHWESTERLY SHEAR CAUSED
BY STRONG UPPER LEVEL WESTERLIES AND ENSUING DRY AIR ENTRAINMENT.
THEREFORE, TS 13W IS FORECAST TO BEGIN A WEAKENING TREND AT TAU 24 AND
ULTIMATELY DISSIPATE BY TAU 60.
MODEL DISCUSSION: TRACK MODEL GUIDANCE IS IN GOOD AGREEMENT FOR THE
REMAINDER OF THE FORECAST PERIOD WITH A CROSS TRACK SPREAD OF 140
NM AT TAU 60. MODEL TRACK SPEED HAS ALSO COME INTO BETTER AGREEMENT,
WITH THE ONLY OUTLIER OF NAVGEM BEING EXCLUDED AS MUCH SLOWER, ALONG
TRACK SPREAD IS 85 NM AT TAU 60. THE OFFICIAL JTWC FORECAST TRACK IS
PLACED WITH HIGH CONFIDENCE, IN LINE WITH THE MULTI-MODEL CONSENSUS
AND SLIGHTLY FASTER MORE IN ACCORDANCE WITH THE AI CONSENSUS.
INTENSITY MODEL GUIDANCE HAS ALSO COME INTO BETTER AGREEMENT WITH
DECAY-SHIPS (GFS BASED) REMAINING THE ONLY OUTLIER WITH A GRADUAL
INTENSIFICATION TREND OUT TO TAU 96, THE REMAINDER OF GUIDANCE AGREES
ON A GENERAL WEAKENING PHASE BEYOND TAU 24. THE OFFICIAL JTWC FORECAST
INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE, CLOSELY IN LINE WITH THE
MULTI-MODEL CONSENSUS OUT TO TAU 36 BUT THEN DIVERGING FROM THE BULK
OF GUIDANCE EXPECTIN…
HAFS and GEFS guidance is only available for storms in the US/NHC domain (Atlantic & East/Central Pacific). For this system, the basin summary and best-track position are shown.
WDPN33 PGTW 100300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 14W (CHAN-HOM) WARNING NR
013//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 33.7N 149.7E
INITIAL INTENSITY: 40 KTS
GEOGRAPHIC REFERENCE: 503 NM EAST OF YOKOSUKA, JAPAN
MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 07 KTS
SIGNIFICANT WAVE HEIGHT: 16 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TROPICAL
STORM (TS) 14W (CHAN-HOM) GAINING SOME CONVECTION OVER ITS
NORTHEASTERN QUADRANT OVER THE PAST SIX HOURS, WHILE THE LOW LEVEL
CIRCULATION CENTER (LLCC) REMAINS FULLY EXPOSED. ENHANCED POLEWARD
OUTFLOW IS ALSO VISIBLE IN MSI AS THE PREVIOUS UPPER LEVEL LOW
POSITIONED TO THE NORTH OF TS 14W RETREATS, AND OUTFLOW BECOMES
DOMINATED BY AN UPPER LEVEL LOW CENTERED OVER HONSHU. OTHERWISE,
ENVIRONMENTAL CONDITIONS ARE ASSESSED AS MARGINAL AS THE SYSTEM IS
IN AN AREA OF LOW TO MODERATE (15-20 KTS) VERTICAL WIND SHEAR
(VWS), BORDERLINE (26-27 C) SEA SURFACE TEMPERATURES, AND DRY AIR
ENTRAINMENT ON THE SOUTHWESTERN FLANK. THE INITIAL POSITION AND
INTENSITY ARE ASSESSED WITH HIGH CONFIDENCE BASED ON A BULLSEYE
092356Z METOP-B ASCAT IMAGE DEPICTING A WELL DEFINED SWATH OF 35 TO
40 KTS IN THE NORTHEASTERN QUADRANT.
INITIAL WIND RADII BASIS: 092356Z METOP-B ASCAT DATA
CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) CENTERED TO THE
NORTHEAST NEAR THE ALEUTIAN ISLANDS
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.0 - 30 KTS
RJTD: T2.0 - 30 KTS
RCTP: T2.0 - 30 KTS
CIMSS ADT: 30 KTS AT 092330Z
CIMSS AIDT: 31 KTS AT 092330Z
CIMSS D-PRINT: 31 KTS AT 092330Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINAL
VWS: 15-20 KTS
SST: 26-27 CELSIUS
OUTFLOW: STRONG POLEWARD
OTHER FACTORS: UPPER LEVEL LOW CENTERED OVER NORTHERN HONSHU AND
DRY AIR ENTRAINMENT
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: HIGH
INITIAL WIND RADII: HIGH
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.
FORECAST DISCUSSION: TS 14W IS FORECAST TO TRACK NORTHWESTWARD OUT
TO TAU 12 AND THEN SUBSEQUENTLY TURNING WESTWARD UNDER THE STEERING
INFLUENCE OF THE SUBTROPICAL RIDGE (STR) CENTERED TO THE NORTHEAST
OVER THE ALEUTIAN ISLANDS. TS 14W IS FORECAST TO MAKE LANDFALL OVER
CENTRAL HONSHU JUST BEFORE TAU 36 AND REEMERGE OVER THE SEA OF
JAPAN (SOJ) BY TAU 48. TS 14W IS EXPECTED TO CONTINUE ON A WESTWARD
TRACK FOR THE REMAINDER OF THE FORECAST PERIOD, AT A SLOWER TRACK
SPEED ONCE ENTERING THE SOJ AS IT ENCOUNTERS INCREASED SHEAR.
REGARDING INTENSITY, TS 14W IS FORECAST TO INTENSIFY IN THE
SHORT-TERM AS IT APPROACHES A STRONG UPPER LEVEL LOW CENTERED OVER
NORTHERN HONSHU, ENHANCING OUTFLOW ALOFT. INTENSITY IS FORECAST TO
DECREASE JUST PRIOR TO LANDFALL AS THE POSITION OF THE UPPER LEVEL
LOW MOVES SOUTHEASTWARD OFF THE COAST OF JAPAN, DECREASING OUTFLOW
ALOFT IN ADDITION TO COLD (23-24 C) SSTS JUST OFF THE COAST OF
HONSHU AND INCREASED DRY AIR ENTRAINMENT. INTENSITY IS EXPECTED TO
FURTHER DECREASE AS TS 14W INTERACTS WITH THE TERRAIN OF JAPAN,
REEMERGING OVER THE SOJ BELOW TROPICAL STORM LEVELS. THE
INCREASINGLY HOSTILE CONDITIONS IN THE SOJ OF DRY AIR AND HIGH
(OVER 30 KTS) VWS RESULT IN FORECAST SUBTROPICAL TRANSITION (STT)
BEGINNING NO LATER THAN TAU 60 AND COMPLETING BY TAU 72 AS TS 14W
DISSIPATES OVER WATER.
MODEL DISCUSSION: TRACK MODEL GUIDANCE IS IN GOOD AGREEMENT OF
LANDFALL OVER HONSHU AROUND TAU 36 FOLLOWED BY REEMERGENCE INTO THE
SOJ WITH THE NOTABLE OUTLIER OF GOOGLE DEEPMIND, WHICH HAS SHIFTED
SOUTH AFTER TAU 24, TRACKING DIRECTLY OVER TOKYO AND KEEPING TS 14W
OVER THE WESTERN COAST OF HONSHU FOR THE REMAINDER OF THE FORECAST
PERIOD. THE OFFICIAL JTWC FORECAST IS THUS PLACED WITH MEDIUM
CONFIDEN…
HAFS and GEFS guidance is only available for storms in the US/NHC domain (Atlantic & East/Central Pacific). For this system, the basin summary and best-track position are shown.
WDPN34 PGTW 100300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 15W (FIFTEEN)
WARNING NR 001//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 25.6N 160.1E
INITIAL INTENSITY: 30 KTS
GEOGRAPHIC REFERENCE: 522 NM NORTHWEST OF WAKE ISLAND
MOVEMENT PAST 6 HOURS: NORTH-NORTHEASTWARD AT 11 KTS
SIGNIFICANT WAVE HEIGHT: 12 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TROPICAL
DEPRESSION 15W WITH A SMALL SYMMETRICAL CENTRAL DENSE OVERCAST
(CDO) FEATURE OBSCURING THE LOW-LEVEL CIRCULATION CENTER (LLCC). A
092248Z METOP-C ASCAT PASS REVEALED THAT THE WIND FIELD IS HIGHLY
ASYMMETRIC WITH A MARKED WEAKNESS IN THE WESTERN SEMICIRCLE. WINDS
ON THE EASTERN SIDE WERE MEASURED TO BE AROUND 25-30 KTS, LENDING
HIGH CONFIDENCE TO THE INITIAL INTENSITY ASSESSMENT. THE INITIAL
POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON THE MSI AND
EXTRAPOLATION FROM THE ASCAT PASS. ENVIRONMENTAL ANALYSIS INDICATES
THAT TD 15W IS IN A MARGINAL ENVIRONMENT CHARACTERIZED BY MODERATE
POLEWARD OUTFLOW ALOFT, LOW TO MODERATE (15-20 KTS) WESTERLY
VERTICAL WIND SHEAR, DRY AIR ENTRAINMENT, AND WARM (29-30 C) SEA
SURFACE TEMPERATURES.
INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND
RADII).
CURRENT STEERING MECHANISM: LARGE-SCALE DEEP-LAYER CYCLONIC FLOW
CENTERED TO THE NORTHWEST
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.0 - 30 KTS
RJTD: T1.0 - 25 KTS
KNES: T1.5 - 25 KTS
PHFO: T2.0 - 30 KTS
CIMSS D-PRINT: 36 KTS AT 100000Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINAL
VWS: 15-20 KTS
SST: 29-30 CELSIUS
OUTFLOW: MODERATE POLEWARD
OTHER FACTORS: DRY AIR ENTRAINMENT FROM THE WEST
ANALYSIS CONFIDENCE:
INITIAL POSITION: MEDIUM
INITIAL INTENSITY: HIGH
INITIAL WIND RADII: NOT APPLICABLE
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THIS INITIAL PROGNOSTIC REASONING
MESSAGE ESTABLISHES THE FORECAST PHILOSOPHY.
FORECAST DISCUSSION: TD 15W IS FORECAST TO TRACK NORTHWARD WITHIN
THE LARGE-SCALE CYCLONIC FLOW THROUGH THE REST OF ITS SHORT LIFESPAN.
AN INCOMING UPPER-LEVEL TROUGH IS EXPECTED TO PROPAGATE EASTWARD AND
CRASH INTO 15W, INDUCING OVER 30 KTS OF WESTERLY SHEAR ON THE SYSTEM
WITHIN THE NEXT 12 HOURS. THE HIGH SHEAR COMBINED WITH AN ASYMMETRIC
WIND FIELD IS EXPECTED TO QUICKLY WEAKEN 15W. COMPLETE DISSIPATION AND
UNRAVELING OF THE VORTEX IS FORECAST TO OCCUR AROUND TAU 24.
MODEL DISCUSSION: NUMERICAL MODEL TRACK GUIDANCE IS IN RELATIVELY
POOR AGREEMENT CONSIDERING HOW SHORT THE FORECAST PERIOD IS.
CROSS-TRACK SPREAD AT TAU 24 IS OVER 100 NM, WHICH IS PRIMARILY DUE
TO THE ECMWF DETERMINISTIC TRACKER SHOWING AN IMMINENT NORTHWESTWARD
TURN. THE JTWC TRACK FORECAST IS PLACED CLOSE TO THE MULTI-MODEL
CONSENSUS WITH MEDIUM CONFIDENCE. RELIABLE INTENSITY GUIDANCE AGREES
ON WEAKENING THROUGH TAU 24 AND THE JTWC INTENSITY FORECAST FOLLOWS
SUIT.
FORECAST CONFIDENCE:
TRACK 00-72 HR: MEDIUM
INTENSITY 00-72 HR: MEDIUM//
NNNN
ECMWF 10-m Streamlines
This map visualizes near-surface winds from the ECMWF operational model using streamlines — continuous curves that show the direction of the wind at every point. Streamlines help us visually detect patterns of atmospheric flow, such as jets, troughs, and areas of rotation.
Forecasters at the NHC monitor 10-meter wind fields for signs of a closed low-level circulation — a common feature of early tropical cyclone formation. When streamlines wrap into a tight, circular pattern and form a closed loop, it may signal that a system is transitioning from a disorganized disturbance into a structured cyclone.
This early organization of wind flow is a key threshold in classifying an area as a potential tropical cyclone. While other ingredients like convection and mid-level humidity are also necessary, closed low-level circulation is often the first structural milestone forecasters look for.
Look for small, circular loops in the streamlines over oceanic regions — especially where other environmental factors also align for storm formation.
ECMWF Predictions
No active storm found in ECMWF data at this time.
Environmental Indicators
Hypothetical TC Drift Paths
This map displays hypothetical tropical cyclone (TC) paths projected from genesis-favorable zones identified by an environmental mask. These paths are computed using the Emanuel Beta and Advection Model, a physically based framework that estimates the motion of nascent cyclones by combining steering-level winds and planetary rotation effects.
The model blends winds from two critical pressure levels — 850 hPa (lower troposphere) and 250 hPa (upper troposphere) — weighted toward the lower level where most of a tropical cyclone's mass resides. It also incorporates a background component associated with beta drift, which arises from the variation of the Coriolis force with latitude.
Each pink trajectory represents a storm initialized from a grid cell where all five environmental thresholds were favorable: high CAPE, low vertical wind shear, high mid-level humidity, warm SSTs, and positive low-level vorticity. Arrows darken with time, tracing the cyclone’s evolution in 6-hour steps. These tracks can move over land given the steering winds, but in reality these storms weaken quickly when no longer over warm water. This means the tracks that move over significant would likely die out quickly and are not well represented in this model.
Hypothetical storms often drift westward and poleward, steered by large-scale tropical flow and Earth's rotation — this helps forecasters anticipate where early-stage disturbances might evolve into organized storms.
Pressure & Rainfall (hPa)
This chart shows 24-hour forecasts of surface pressure (in hPa) and precipitation (in mm) for select U.S. cities.
The data comes from the Open-Meteo API,
which sources its predictions from high-resolution numerical weather models like ICON (from the German Weather Service)
and ECMWF's IFS. These are advanced general circulation models (GCMs) that solve physical equations governing the
atmosphere — including thermodynamics, fluid motion, and radiation — to simulate and forecast future states of weather.
A sudden drop in pressure may signal the approach of a developing storm system. Increasing rainfall intensity often
tracks with tropical activity or frontal systems. These paired indicators help visualize evolving atmospheric instability and potential hazards.
NBDC Gulf Buoy Data
This data comes from the National Data Buoy Center (NDBC), a division of NOAA responsible for monitoring ocean
and atmospheric conditions using moored buoys, coastal stations, and drifting floats. These sensors play a vital role in
tracking tropical cyclone development by recording variables like wind speed,
barometric pressure, air & sea surface temperatures, and wave height — all of which
help determine storm structure and intensification.
A sudden drop in sea-level pressure or a spike in wind gusts can signal rapid cyclone strengthening.
Water temperature above ~26°C is a key fuel source for tropical cyclones. Wave and swell height give insight
into the storm’s reach and energy transfer across the ocean. Monitoring these in real time helps improve forecasts and early warnings.
Wind: ESE (110°), 11.7 kt | Gust: 13.6 kt
Pressure: 30.07 rising | Air Temp: 85.8 °F
Water Temp: 85.8 °F | Dew Point: 79.3 °F
Swell: 0.7 ft | Wind Wave: 1.3 ft
NWS U.S. Radar
The National Weather Service (NWS) collects radar data using the NEXRAD (Next Generation Radar) network —
a nationwide system of over 150 high-resolution Doppler radar stations. Radar works by emitting pulses of energy
that bounce off precipitation (like raindrops, hail, or snow) and return to the radar dish. Doppler radar not only detects the
location and intensity of storms, but also their motion — by measuring shifts in frequency caused by movement of particles toward
or away from the radar site. This allows meteorologists to spot rotating storms and potential tornadoes in real time.
GOES 15-min Satellite
The GOES (Geostationary Operational Environmental Satellite) system is operated by NOAA
and provides continuous weather observation over the Americas. Orbiting 22,300 miles above Earth,
GOES satellites deliver high-resolution imagery every 15 minutes, helping track tropical systems, cloud formation,
and atmospheric motion in real time. The Geocolor imagery shown here combines visible and infrared data
to highlight clouds, land, and sea in a natural-looking format.
GOES Band 13 – Infrared (IR) Imagery
Band 13 (10.3 µm) is one of the most important infrared channels for tropical meteorology, measuring emitted radiation from cloud tops.
Colder colors (red, yellow) signal deep convection, where strong thunderstorms punch through the upper atmosphere.
These features often indicate the early stages of tropical cyclone formation.
Most recent GOES Band 13 image. Provided by NOAA/NESDIS/STAR.
