🚨 New Hanover, NC; Pender, NC: Severe Thunderstorm Warning issued August 21 at 1:39PM EDT until August 21 at 2:45PM EDT by NWS Wilmington NC     🚨 Hoke, NC; Moore, NC; Richmond, NC; Scotland, NC: Flood Advisory issued August 21 at 1:38PM EDT until August 21 at 4:45PM EDT by NWS Raleigh NC     🚨 Montgomery: None     🚨 Lipscomb; Hutchinson; Roberts; Hemphill; Gray; Wheeler; Armstrong; Donley: Heat Advisory issued August 21 at 12:32PM CDT until August 21 at 9:00PM CDT by NWS Amarillo TX     🚨 Collingsworth; Palo Duro Canyon: Heat Advisory issued August 21 at 12:32PM CDT until August 21 at 9:00PM CDT by NWS Amarillo TX     🚨 Onslow, NC: Severe Thunderstorm Warning issued August 21 at 1:31PM EDT until August 21 at 1:45PM EDT by NWS Newport/Morehead City NC     🚨 Craven, NC; Jones, NC: Severe Thunderstorm Warning issued August 21 at 1:28PM EDT until August 21 at 2:15PM EDT by NWS Newport/Morehead City NC     🚨 Hoke, NC; Scotland, NC: Severe Thunderstorm Warning issued August 21 at 1:28PM EDT until August 21 at 2:30PM EDT by NWS Raleigh NC     🚨 Union; Southern Spartanburg: Special Weather Statement issued August 21 at 1:27PM EDT by NWS Greenville-Spartanburg SC     🚨 Henderson; Navarro; Anderson: Heat Advisory issued August 21 at 12:23PM CDT until August 21 at 8:00PM CDT by NWS Fort Worth TX    

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: 17 UTC 21 Aug 2026

Active storms summary

Select a Storm

LALA (CP012026)

Type: HU Max Wind: 85 kt Min Pressure: 970 hPa Position: 27.0, -171.3 Basin: East Pacific

TWO (CP022026)

Type: TD Max Wind: 30 kt Min Pressure: 1005 hPa Position: 13.2, -145.6 Basin: East Pacific

91E (EP912026)

Type: DB Max Wind: 20 kt Min Pressure: 1009 hPa Position: 9.0, -115.0 Basin: East Pacific
2-Day Formation: 60% (Medium) 5-Day Formation: N/A (N/A)

SAUDEL (WP172026)

Type: HU Max Wind: 70 kt Min Pressure: 983 hPa Position: 16.0, 148.1 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.
WDPN31 PGTW 211500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 17W (SAUDEL) WARNING NR 013// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 16.0N 148.1E INITIAL INTENSITY: 70 KTS GEOGRAPHIC REFERENCE: 141 NM EAST-NORTHEAST OF SAIPAN MOVEMENT PAST 6 HOURS: NORTH-NORTHWESTWARD AT 13 KTS SIGNIFICANT WAVE HEIGHT: 28 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: NOW A TYPHOON, 17W HAS UNDERGONE RAPID INTENSIFICATION (RI), WITH ITS INTENSITY INCREASING BY 30 KTS IN THE PAST 24 HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS AN EXPANDING CONVECTIVE ENVELOPE AS FEEDER BANDS EXPLODE OVER THE NORTHERN AND EASTERN PERIPHERY. TY 17W NOW HAS A RAGGED EYE AS THE CENTRAL DENSE OVERCAST ASSOCIATED WITH THE INNER CORE HAS BECOME BETTER DEFINED. THE INCREASING UPPER-LEVEL DIVERGENCE CAN BE LARGELY ATTRIBUTED TO EXCELLENT POLEWARD OUTFLOW ALOFT. THE SYSTEM IS IN A HIGHLY FAVORABLE ENVIRONMENT OF HIGH OCEAN HEAT CONTENT (OHC), LOW VERTICAL WIND SHEAR (VWS), AND RICH, DEEP-LAYER MOISTURE. THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE BASED ON THE RAGGED EYE FEATURE AND THE TIGHT GROUPING OF AGENCY FIXES. THE SUBJECTIVE DVORAK ESTIMATES HAVE BEEN RISING, WITH PGTW, KNES, AND RCTP ALL REPORTING T4.0. IN FACT, APPLYING THE EIR-EYE TECHNIQUE YIELDS A DATA T-NUMBER OF 4.5. THESE ESTIMATES, COMBINED WITH THE IMPROVED CONVECTIVE SIGNATURE, JUSTIFY RAISING THE INITIAL INTENSITY TO 70 KTS WITH HIGH CONFIDENCE. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: SOUTHWESTERN FLANK OF A SUBTROPICAL RIDGE (STR) CENTERED TO THE NORTHEAST AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T4.0 - 65 KTS RJTD: T3.5 - 55 KTS RCTP: T4.0 - 65 KTS KNES: T4.0 - 65 KTS CIMSS SATCON: 57 KTS AT 210510Z CIMSS ADT: 49 KTS AT 211210Z CIMSS AIDT: 45 KTS AT 211210Z CIMSS D-MINT: 63 KTS AT 211227Z CIMSS D-PRINT: 60 KTS AT 211210Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY FAVORABLE VWS: 5-10 KTS SST: 29-30 CELSIUS OUTFLOW: MODERATE RADIAL ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: HIGH INITIAL WIND RADII: MEDIUM 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THE JTWC FORECAST TRACK HAS SHIFTED SOUTHWARD BY 20 NM AT TAU 96 AND 36 NM AT TAU 120. FORECAST DISCUSSION: TY 17W CONTINUES TO MOVE NORTH-NORTHWESTWARD AT AN AVERAGE SPEED OF 10-13 KTS ALONG THE SOUTHWESTERN FLANK OF AN ELONGATED STR TO ITS NORTHEAST. THIS MOTION WILL HOLD THROUGH TAU 36. AFTER THIS POINT, THE STR WILL MIGRATE WESTWARD, WHICH WILL FORCE THE SYSTEM ONTO A MORE WESTWARD TRACK. IN THE EXTENDED PERIOD, LOW CONFIDENCE REMAINS DUE TO THE UNCERTAIN IMPACT OF THE MONSOON DEPRESSION, DESIGNATED AS 94W, ON A SEPARATE STR OVER HONSHU. A STRONGER 94W WOULD ERODE THE STR, CREATING A WEAKNESS THAT WOULD ALLOW TY 17W TO SLOW AND TURN POLEWARD, BRINGING THE SYSTEM CLOSER TO THE NORTHERN RYUKYU ISLANDS AND KYUSHU. ON THE OTHER HAND, A WEAKER 94W WOULD LEAVE THE STR INTACT, CAUSING TY 17W TO CONTINUE ON A MORE WESTWARD TRAJECTORY TOWARD THE SOUTHERN OR CENTRAL RYUKYU ISLANDS. THE JTWC FORECAST CURRENTLY FAVORS THE LATTER SCENARIO AND DEPICTS A MORE ZONAL TRACK AT TAU 96 AND TAU 120. RAPID INTENSIFICATION (RI) BEGAN APPROXIMATELY 24 HOURS AGO AND WILL CONTINUE. OVER THE NEXT 36 HOURS, TY 17W WILL TRAVERSE VERY HIGH OHC WITHIN A LOW-SHEAR ENVIRONMENT. CONSEQUENTLY, THE SYSTEM WILL CONTINUE TO RAPIDLY DEEPEN TO A PEAK INTENSITY OF 125 KTS AT TAU 48. AFTERWARD, THE INTENSIFICATION PHASE WILL END AS THE SYSTEM MOVES OVER PROGRESSIVELY LOWER OHC. A STEADY WEAKENING TREND WILL COMMENCE AT TAU 96, DRIVEN BY LOWER SEA SURFACE TEMPERATURES, UPWELLING OF COOLER WATERS CAUSED BY A SLOWING FORWARD MOTION, AND INCREASING VWS. MODEL DISCUSSION: THE TRACK GUIDANCE SUITE IS IN EXCELLENT AGREEMENT THROUGH TA…

EIGHTEEN (WP182026)

Type: TS Max Wind: 35 kt Min Pressure: 994 hPa Position: 20.8, 108.8 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 211500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 18W (EIGHTEEN) WARNING NR 004// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 20.8N 108.8E INITIAL INTENSITY: 35 KTS GEOGRAPHIC REFERENCE: 163 NM EAST OF HANOI, VIETNAM MOVEMENT PAST 6 HOURS: NORTHEASTWARD AT 03 KTS SIGNIFICANT WAVE HEIGHT: 12 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: OVER THE PAST SIX HOURS, A MASS OF VERY DEEP CONVECTION HOOKED ONTO THE WESTERN FLANK OF TS 18W. THIS HAS VISIBLY CAUSED THE LOW-LEVEL CIRCULATION CENTER (LLCC) TO SPIN UP. THIS CONVECTION HAS SINCE WEAKENED AND PROGRESSED INLAND OVER QINZHOU. THE LLCC REMAINS OVER THE VERY WARM WATERS OF THE GULF OF TONKIN, BUT THE MODERATE TO HIGH VERTICAL WIND SHEAR (VWS) HAS TAKEN A TOLL ON THE CONVECTIVE ACTIVITY THAT WAS ONCE OVER THE CENTER. A 211032Z WSFM MWI 37 GHZ IMAGE REVEALED A RATHER DISORGANIZED LOWER-LEVEL STRUCTURE WITH HEAVY PRECIPITATION OCCURRING WITHIN THE WESTERN SIDE OF THE CENTER. DRY AIR IS BEING PULLED NORTHWARD AND IS ENVELOPING THE CIRCULATION, WHICH IS SUPPRESSING CONVECTIVE ACTIVITY. THE INITIAL POSITION IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON A PARTIALLY EXPOSED LLCC IN THE ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY. THE INITIAL INTENSITY HAS BEEN RAISED TO 35 KTS WITH MEDIUM CONFIDENCE BASED ON THE RISING OBJECTIVE INTENSITY ESTIMATES FROM CIMSS, WHICH RANGED FROM 36 KTS TO 43 KTS. INITIAL WIND RADII BASIS: WSFM MICROWAVE IMAGERY CURRENT STEERING MECHANISM: WEAK STEERING ENVIRONMENT AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T2.0 - 30 KTS RJTD: T1.5 - 25 KTS CIMSS SATCON: 40 KTS AT 211140Z CIMSS ADT: 43 KTS AT 211210Z CIMSS AIDT: 36 KTS AT 211210Z CIMSS D-MINT: 39 KTS AT 211030Z CIMSS D-PRINT: 37 KTS AT 211140Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: UNFAVORABLE VWS: 15-20 KTS SST: 29-30 CELSIUS OUTFLOW: WEAK 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: TROPICAL STORM (TS) 18W IS LOCATED WITHIN A WEAK STEERING ENVIRONMENT. A WEAK SUBTROPICAL RIDGE (STR) OVER SOUTHEAST CHINA TRIES TO DRIVE THE SYSTEM WESTWARD, BUT THE DEEP-LAYER SOUTHWESTERLIES TO THE SOUTH ATTEMPT TO MOVE IT IN THE OPPOSITE DIRECTION. THE END RESULT IS A VERY SLOW RATE OF FORWARD MOVEMENT TOWARD THE NORTHEAST. THE STR WILL WEAKEN OVER THE NEXT 12 HOURS. THEREFORE, THE JTWC FORECAST TRACK PRESUMES THAT THE STEERING INFLUENCE OF THE SOUTHWESTERLY FLOW WILL DOMINATE AND CALLS FOR A GENERAL NORTHEASTWARD TO EASTWARD MOTION THROUGH THE PERIOD. WITH MOST OF THE CONVECTION NOW INLAND AND VERY LITTLE OVER THE CIRCULATION, THE SYSTEM HAS LIKELY REACHED PEAK INTENSITY. THE ENVIRONMENT WILL BE PERSISTENTLY UNFAVORABLE FOR DEVELOPMENT, CHARACTERIZED BY WARM SST STRONGLY OFFSET BY MODERATE TO HIGH VWS AND DRY AIR. THE JTWC INTENSITY FORECAST ASSUMES THAT CONVECTION WILL ATTEMPT TO REBUILD OVER THE CIRCULATION WHILE IT REMAINS OVER WARM WATERS, WHICH WILL HELP MAINTAIN INTENSITY IN THE FACE OF UNDESIRABLE SHEAR OVER THE NEXT 36 HOURS. ONCE THE VORTEX MAKES LANDFALL, IT WILL DISSIPATE BY TAU 72. MODEL DISCUSSION: THE CONFIDENCE IN THE TRACK FORECAST IS VERY LOW. A SLIGHTLY STRONGER STR COULD BRIEFLY STEER THE SYSTEM WESTWARD, AND SEVERAL MODEL TRACKERS DEPICT THIS SCENARIO. ALTHOUGH MOST OF THE GUIDANCE EVENTUALLY BRINGS THE CIRCULATION EASTWARD, THE BRIEF WESTWARD MOTION WOULD DELAY THE INEVITABLE TRACK TOWARD LAND. AN ALTERNATE SCENARIO IN WHICH THE SHEAR COMPLETELY OVERWHELMS THE SYSTEM, LEADING TO DISSIPATION OVER WATER, IS ALSO POSSIBLE. SUBSEQUENT FORECASTS MAY LEAN TOWARD THE ALTERNATE SCENARIOS, WHICH WOULD CHANGE THE …

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: W (280°), 3.9 kt   |   Gust: 5.8 kt

Pressure: 30.08   |   Air Temp: 86.7 °F

Water Temp: 87.4 °F   |   Dew Point: 79.2 °F

Swell:   |   Wind Wave:

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.