🚨 Yuma County; Kit Carson County; Cheyenne: Special Weather Statement issued August 8 at 6:30PM MDT by NWS Goodland KS 🚨 Greenville, SC: Flood Advisory issued August 8 at 8:28PM EDT until August 8 at 10:30PM EDT by NWS Greenville-Spartanburg SC 🚨 Cherokee; Nacogdoches; Shelby; Angelina; San Augustine: Special Weather Statement issued August 8 at 7:27PM CDT by NWS Shreveport LA 🚨 Montgomery: None 🚨 Kearny, KS: Severe Thunderstorm Warning issued August 8 at 7:26PM CDT until August 8 at 7:45PM CDT by NWS Dodge City KS 🚨 Breathitt; Owsley; Perry: Special Weather Statement issued August 8 at 8:26PM EDT by NWS Jackson KY 🚨 Delaware, OH; Fairfield, OH; Franklin, OH; Licking, OH: Severe Thunderstorm Warning issued August 8 at 8:25PM EDT until August 8 at 9:15PM EDT by NWS Wilmington OH 🚨 Warren: Special Weather Statement issued August 8 at 8:24PM EDT by NWS State College PA 🚨 Emmons, ND: Severe Thunderstorm Warning issued August 8 at 7:23PM CDT until August 8 at 8:15PM CDT by NWS Bismarck ND 🚨 West Feliciana; Wilkinson: Special Weather Statement issued August 8 at 7:22PM CDT by NWS New Orleans LA
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 082100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 12W (DOLPHIN) WARNING NR 052//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 27.2N 124.0E
INITIAL INTENSITY: 75 KTS
GEOGRAPHIC REFERENCE: 184 NM NORTHEAST OF TAIPEI, TAIWAN
MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 07 KTS
SIGNIFICANT WAVE HEIGHT: 34 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS TYPHOON
(TY) 12W (DOLPHIN) YET AGAIN LOSING A DISCERNIBLE EYE FEATURE AS
THE COMPACT CENTER HAS BECOME CLOUD FILLED. TY 12W HAS MAINTAINED
STRONG BANDING FEATURES AND A MASSIVE OVERALL CONVECTIVE STRUCTURE,
MEASURING OVER 600 NM IN DIAMETER AS ITS OUTERMOST RAINBANDS BEGIN
TO MAKE LANDFALL OVER EASTERN CHINA. ENVIRONMENTAL ANALYSIS REVEALS
FAVORABLE CONDITIONS WITH LOW (5-10 KTS) OF VERTICAL WIND SHEAR,
WARM (29-30 C) SEA SURFACE TEMPERATURES (SSTS), AND GOOD OUTFLOW
ALOFT. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON
THE DIMPLE EYE FEATURE IN EIR IMAGERY AS WELL AS EXTRAPOLATION FROM
A 071425Z GMI 89 GHZ MICROWAVE IMAGE DEPICTING A MICROWAVE EYE. THE
INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE
SPREAD BETWEEN AGENCY DVORAK FIXES AND CIMSS OBJECTIVE ESTIMATES
LISTED BELOW, HEDGING CLOSER TO THE MICROWAVE IMAGERY BASED DMINT
AS THE ADT VALUE HAS BEEN OBSERVED TO STRUGGLE DURING THESE TIME
PERIODS OF THE EYE QUICKLY APPEARING AND THEN FILLING.
INITIAL WIND RADII BASIS: WIND RADII ADJUSTED BASED ON AN 081153Z
METOP B ASCAT IMAGE.
CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) CENTERED OVER
SOUTHERN HONSHU.
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T5.0 - 90 KTS
RJTD: T5.0 - 90 KTS
KNES: T5.0 - 90 KTS
CIMSS ADT: 69 KTS AT 081700Z
CIMSS AIDT: 78 KTS AT 081700Z
CIMSS D-MINT: 77 KTS AT 081423Z
CIMSS D-PRINT: 84 KTS AT 081700Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 5-10 KTS
SST: 29-30 CELSIUS
OUTFLOW: STRONG RADIAL
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: MEDIUM
INITIAL WIND RADII: HIGH
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.
FORECAST DISCUSSION: TY 12W IS FORECAST TO CONTINUE ITS
WEST-NORTHWESTWARD TRACK AND MAKE LANDFALL OVER EASTERN CHINA
ROUGHLY 200 NM SOUTH OF SHANGHAI BETWEEN TAUS 12 AND 24. TY 12W IS
THEN EXPECTED TO TURN POLEWARD ON A NORTHWESTWARD TRACK FOR THE
REMAINDER OF THE FORECAST PERIOD UNDER THE STEERING INFLUENCE OF A
SUBTROPICAL RIDGE (STR) CURRENTLY CENTERED OVER SOUTHERN HONSHU.
THIS STR IS EXPECTED TO BUILD AND EXTEND SOUTHWARD, THUS GIVING 12W
A MORE POLEWARD TRACK. IN REGARDS TO INTENSITY, 12W IS FORECAST TO
DECREASE SLIGHTLY IN INTENSITY OVER WATER AS IT MOVES AWAY FROM AN
AREA OF HIGHER OHC. UPON MAKING LANDFALL, A STEEP DECLINE IN
INTENSITY IS FORECAST AS TERRAIN INTERACTION OCCURS, ULTIMATELY
RESULTING IN THE DISSIPATION OF TY 12W OVER LAND NO LATER THAN TAU
60.
MODEL DISCUSSION: TRACK MODEL GUIDANCE IS IN GOOD AGREEMENT FOR THE
REMAINDER OF THE FORECAST PERIOD WITH THE EXCEPTION OF GFS WHICH
TRACKS 12W MUCH FARTHER TO THE SOUTH. AN ADJUSTED CONSENSUS WAS RUN
EXCLUDING THIS OUTLIER AND USING THE BEST PERFORMING MODELS
THROUGHOUT THE LIFESPAN OF 12W TO CREATE THE FORECAST TRACK. THE
OFFICIAL JTWC FORECAST TRACK IS LAID WITH HIGH CONFIDENCE FOR THE
REMAINDER OF THE FORECAST PERIOD, CLOSELY IN LINE WITH THE ADJUSTED
MULTI-MODEL CONSENSUS, AI CONSENSUS, AND EXPERIMENTAL GOOGLE
DEEPMIND MODEL. MODEL INTENSITY GUIDANCE IS ALSO IN GOOD AGREEMENT
WITH THE EXCEPTION OF HWRF WHICH DOES NOT DEPICT AS SHARP OF A
DECREASE UPON LANDFALL WITH CHINA. EXCLUDING HWRF, THE REMAINDER OF
THE MODEL GUIDANCE MAINTAINS A 15 TO 20 KT SPREAD THROUGHOUT THE
FORECAST PERIOD. THE OFFICIAL …
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.
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 082100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 14W (CHAN-HOM) WARNING
NR 008//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 32.7N 151.7E
INITIAL INTENSITY: 40 KTS
GEOGRAPHIC REFERENCE: 617 NM EAST OF YOKOSUKA, JAPAN
MOVEMENT PAST 6 HOURS: WEST-SOUTHWESTWARD AT 11 KTS
SIGNIFICANT WAVE HEIGHT: 20 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS TROPICAL
STORM 14W (CHAN-HOM) WITH A FULLY EXPOSED LOW-LEVEL CIRCULATION
CENTER (LLCC) AND A BAND OF WEAK CONVECTION ALONG THE SOUTHERN
SEMICIRCLE. THE PLACEMENT OF THE UPPER-LEVEL LOW TO THE EAST
CONTINUES TO INDUCE SUBSIDENCE IN THAT AREA, HINDERING THE
DEVELOPMENT OF CONVECTION. DRY AIR, INDICATED BY A FIELD OF
STRATOCUMULUS CLOUDS, TO THE NORTH AND WEST OF THE SYSTEM CONTINUES
TO ENTRAIN INTO THE CORE OF THE VORTEX, WHICH IS FURTHER IMPEDING
THE DEVELOPMENT OF CENTRAL CONVECTION. A 081533Z AMSR2 36 GHZ
MICROWAVE IMAGE SHOWS A PARTIAL MICROWAVE EYE FEATURE WITH A
DISTINCT WEAKNESS IN THE WESTERN SEMICIRCLE. THE INITIAL POSITION
IS PLACED WITH HIGH CONFIDENCE BASED ON THE AMSR2 IMAGE AND THE
EXPOSED LLCC IN ANIMATED EIR IMAGERY. THE INITIAL INTENSITY OF 40
KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE HIGH SIDE OF
THE AGENCY DVORAK AND CIMSS INTENSITY ESTIMATES LISTED BELOW. THE
LACK OF CENTRAL CONVECTION IS LIKELY CAUSING THE CURRENT INTENSITY
TO BE UNDERESTIMATED BY THE DVORAK-BASED INTENSITY ESTIMATES.
ENVIRONMENTAL ANALYSIS INDICATES THAT 14W IS IN A MARGINALLY
FAVORABLE ENVIRONMENT CHARACTERIZED BY MODERATE EQUATORWARD OUTFLOW
ALOFT, LOW (10-15 KTS) VERTICAL WIND SHEAR, AND WARM (27-28 C) SEA
SURFACE TEMPERATURES OFFSET BY SIGNIFICANT DRY AIR ENTRAINMENT.
INITIAL WIND RADII BASIS: SCATTEROMETER DATA
CURRENT STEERING MECHANISM: WEAK STEERING ENVIRONMENT WITH RIDGING
OVER SOUTHERN HONSHU EXTENDING EASTWARD AND A SUBTROPICAL RIDGE
(STR) POSITIONED TO THE NORTHEAST.
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.5 - 35 KTS
RJTD: T2.0 - 30 KTS
RCTP: T2.5 - 35 KTS
KNES: T2.0 - 30 KTS
CIMSS SATCON: 48 KTS AT 081730Z
CIMSS ADT: 34 KTS AT 081730Z
CIMSS AIDT: 32 KTS AT 081730Z
CIMSS D-MINT: 37 KTS AT 081534Z
CIMSS D-PRINT: 35 KTS AT 081730Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE
VWS: 10-15 KTS
SST: 27-28 CELSIUS
OUTFLOW: MODERATE EQUATORWARD
OTHER FACTORS: DRY AIR ENTRAINMENT WITH A STRONG UPPER-LEVEL LOW
IN CLOSE PROXIMITY TO THE EAST
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: TS 14W IS FORECAST TO TRACK SLOWLY WESTWARD
OVER THE NEXT 12 HOURS AS IT CONTINUES TO BE PLACED WITHIN A WEAK
STEERING ENVIRONMENT. AFTER TAU 12, THE TROUGH TO THE NORTH IS
EXPECTED TO PROPAGATE NORTHEASTWARD, AWAY FROM 14W, AND THE STR TO
THE NORTHEAST WILL BUILD BACK IN. BY TAU 36, THE STEERING PATTERN
WILL BECOME MORE DEFINED AS THE SYSTEM TRACKS ALONG THE
SOUTHWESTERN PERIPHERY OF THE STR WITH INCREASING TRACK SPEEDS.
AROUND TAU 60, RIDGING WILL EXTEND TO THE NORTH OF THE SYSTEM,
CAUSING THE TRAJECTORY TO FLATTEN TO A MORE WESTWARD TRACK AS IT
APPROACHES THE COAST OF HONSHU. LANDFALL IS FORECAST TO OCCUR JUST
AFTER TAU 60 NEAR SENDAI. 14W WILL THEN QUICKLY TRAVERSE OVER
HONSHU AND EMERGE WITHIN THE SEA OF JAPAN AROUND TAU 72 AND
CONTINUE ON A WESTWARD TRACK. SUBTROPICAL TRANSITION IS FORECAST TO
BEGIN ONCE THE SYSTEM EMERGES BACK OVER WATER AS A STRONG
UPPER-LEVEL CYCLONE ANCHORS OVER SOUTHERN HONSHU, INDUCING
SIGNIFICANT VERTICAL WIND SHEAR. BY TAU 96, 14W IS EXPECTED TO HAVE
SHALLOWED OUT AND DECOUPLED UNDER THE EFFECTS OF THE HOSTI…
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.
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 (120°), 5.8 kt | Gust: 7.8 kt
Pressure: 30.00 falling | Air Temp: 83.3 °F
Water Temp: 85.1 °F | Dew Point: 78.6 °F
Swell: 1.6 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.
