🚨 Maricopa, AZ: Severe Thunderstorm Warning issued August 9 at 10:29PM MST until August 9 at 11:15PM MST by NWS Phoenix AZ     🚨 Grundy, IL; La Salle, IL; Livingston, IL: Severe Thunderstorm Warning issued August 10 at 12:29AM CDT until August 10 at 12:45AM CDT by NWS Chicago IL     🚨 San Diego County Coastal Areas; Orange County Coastal: Coastal Flood Advisory issued August 9 at 10:27PM PDT until August 12 at 11:00PM PDT by NWS San Diego CA     🚨 Montgomery: None     🚨 Racine, WI; Walworth, WI: Flash Flood Warning issued August 10 at 12:25AM CDT until August 10 at 3:30AM CDT by NWS Milwaukee/Sullivan WI     🚨 North Point Light to Wind Point WI; Wind Point WI to Winthrop Harbor IL; Lake Michigan from North Point Light to Wind Point WI 5NM offshore to Mid Lake; Lake Michigan from Wind Point WI to Winthrop Harbor IL 5NM offshore to Mid Lake: Marine Weather Statement issued August 10 at 12:25AM CDT by NWS Milwaukee/Sullivan WI     🚨 La Paz, AZ; Maricopa, AZ: Dust Storm Warning issued August 9 at 10:23PM MST until August 9 at 11:00PM MST by NWS Phoenix AZ     🚨 Kent, MI: Flood Advisory issued August 10 at 1:23AM EDT until August 10 at 7:30AM EDT by NWS Grand Rapids MI     🚨 Lake Michigan from Sheboygan to Port Washington WI 5NM offshore to Mid Lake; Lake Michigan from Port Washington to North Point Light WI 5NM offshore to Mid Lake: Marine Weather Statement issued August 10 at 12:21AM CDT by NWS Milwaukee/Sullivan WI     🚨 Winthrop Harbor to Wilmette Harbor IL; Wilmette Harbor to Northerly Island IL; Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5NM offshore to Mid Lake; Lake Michigan from Wilmette Harbor to Michigan City in 5NM offshore to Mid Lake: Special Marine Warning issued August 10 at 12:20AM CDT until August 10 at 12:45AM CDT by NWS Chicago IL    

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.

Summary & NHC 7-Day Formation Outlook

Valid: 05 UTC 10 Aug 2026

Active storms summary

Select a Storm

93C (CP932026)

Type: DB Max Wind: 20 kt Min Pressure: 1007 hPa Position: 10.5, -141.2 Basin: East Pacific

DOLPHIN (WP122026)

Type: TS Max Wind: 55 kt Min Pressure: 970 hPa Position: 27.9, 119.7 Basin: West Pacific
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

PEILOU (WP132026)

Type: TS Max Wind: 40 kt Min Pressure: 996 hPa Position: 20.5, 148.3 Basin: West Pacific
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…

CHAN-HOM (WP142026)

Type: TS Max Wind: 40 kt Min Pressure: 986 hPa Position: 33.7, 149.7 Basin: West Pacific
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…

FIFTEEN (WP152026)

Type: TD Max Wind: 30 kt Min Pressure: 997 hPa Position: 25.6, 160.1 Basin: West Pacific
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.

Streamline Wind Map

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.

TC Drift Path Map

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.

US National Radar Loop

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.

Satellite

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.

GOES IR Band 13

Most recent GOES Band 13 image. Provided by NOAA/NESDIS/STAR.