🚨 Benton, TN; Henry, TN; Weakley, TN: Severe Thunderstorm Warning issued August 20 at 12:31AM CDT until August 20 at 1:00AM CDT by NWS Memphis TN     🚨 Alexander, IL; Ballard, KY; Carlisle, KY; Mississippi, MO: Tornado Warning issued August 20 at 12:31AM CDT until August 20 at 1:00AM CDT by NWS Paducah KY     🚨 Bollinger, MO; Wayne, MO: Flash Flood Warning issued August 20 at 12:31AM CDT until August 20 at 6:30AM CDT by NWS Paducah KY     🚨 Alexander, IL; Ballard, KY; Carlisle, KY; Mississippi, MO; New Madrid, MO; Scott, MO; Stoddard, MO: Severe Thunderstorm Warning issued August 20 at 12:30AM CDT until August 20 at 12:45AM CDT by NWS Paducah KY     🚨 Aguila Valley; Northwest Valley; Tonopah Desert; Buckeye/Avondale; Cave Creek/New River; Deer Valley; North Phoenix/Glendale; New River Mesa; Rio Verde/Salt River; Mazatzal Mountains: Special Weather Statement issued August 19 at 10:29PM MST by NWS Phoenix AZ     🚨 Scott, MO; Stoddard, MO: Severe Thunderstorm Warning issued August 20 at 12:29AM CDT until August 20 at 1:00AM CDT by NWS Paducah KY     🚨 Clay, IN; Parke, IN; Putnam, IN; Vigo, IN: Severe Thunderstorm Warning issued August 20 at 1:28AM EDT until August 20 at 1:45AM EDT by NWS Indianapolis IN     🚨 Montgomery: None     🚨 Mississippi; Dunklin; Pemiscot; Lake; Obion; Dyer: Special Weather Statement issued August 20 at 12:27AM CDT by NWS Memphis TN     🚨 Calloway, KY; Marshall, KY: Tornado Warning issued August 20 at 12:26AM CDT until August 20 at 1:00AM CDT by NWS Paducah KY    

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 20 Aug 2026

Active storms summary

Select a Storm

LALA (CP012026)

Type: HU Max Wind: 100 kt Min Pressure: 959 hPa Position: 22.4, -171.3 Basin: East Pacific

90E (EP902026)

Type: DB Max Wind: 30 kt Min Pressure: 1007 hPa Position: 10.4, -140.0 Basin: East Pacific
2-Day Formation: 90% (High) 5-Day Formation: N/A (N/A)

SAUDEL (WP172026)

Type: TS Max Wind: 35 kt Min Pressure: 999 hPa Position: 11.4, 151.6 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 200300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 17W (SAUDEL) WARNING NR 007// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 11.4N 151.6E INITIAL INTENSITY: 35 KTS GEOGRAPHIC REFERENCE: 235 NM NORTH OF CHUUK MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 15 KTS SIGNIFICANT WAVE HEIGHT: 18 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS THE PARTIALLY EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC) OF TROPICAL STORM (TS) 17W REGAINING SOME CENTRAL CONVECTION, WHICH IS OBSCURING THE CENTER OF THE VORTEX AND THE SOUTHWEST QUADRANT. WEAK BUT APPARENT MID-LEVEL NORTHEASTERLY SHEAR HAS PREVENTED THE CONVECTION FROM WRAPPING AROUND TO THE NORTHERN SEMICIRCLE OVER THE PAST 6 HOURS. ANIMATED WATER VAPOR IMAGERY SHOWS A ROBUST EQUATORWARD OUTFLOW CHANNEL AND A WEDGE OF DRY AIR TO THE NORTHWEST THAT MAY BE A CONTRIBUTING FACTOR TO THE LIMITED CONVECTION OBSERVED. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON PARTIALLY EXPOSED LLCC AND TIGHT AGREEMENT OF THE AGENCY DVORAK FIXES. THE INITIAL INTENSITY OF 35 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE AGENCY DVORAK INTENSITY ESTIMATES AS THERE HAS BEEN A LACK OF RECENT WIND SPEED IMAGERY. TS 17W IS IN A FAVORABLE ENVIRONMENT CHARACTERIZED BY WARM SEA SURFACE TEMPERATURES AND GOOD EQUATORWARD OUTFLOW. THE RELATIVELY LOW 5-10 KTS OF MID-LEVEL SHEAR AND WEAK DRY AIR ENTRAINMENT APPEAR TO BE HAVING AN OUTSIZED NEGATIVE IMPACT ON INTENSIFICATION DUE TO THE SHALLOWNESS OF THE VORTEX. INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK CURRENT STEERING MECHANISM: SOUTHWESTERN EXTENSION OF A SUBTROPICAL RIDGE CENTERED TO THE NORTHEAST AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T2.5 - 35 KTS RJTD: T2.5 - 35 KTS RCTP: T2.0 - 30 KTS KNES: T2.5 - 35 KTS CIMSS ADT: 28 KTS AT 200000Z CIMSS AIDT: 33 KTS AT 200000Z CIMSS D-MINT: 29 KTS AT 192010Z CIMSS D-PRINT: 28 KTS AT 200040Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 5-10 KTS SST: 29-30 CELSIUS OUTFLOW: STRONG EQUATORWARD OTHER FACTORS: WEAK DRY AIR ENTRAINMENT ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: LOW 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TS 17W (SAUDEL) HAS TAKEN ON A SLIGHTLY MORE WESTWARD COMPONENT TO ITS TRACK OVER THE PAST 6 HOURS AS THE STR TO THE NORTHEAST BEGINS TO ASSERT CONTROL OVER THE STEERING ENVIRONMENT. THE SYSTEM IS FORECAST TO CONTINUE TRACKING NORTHWESTWARD UNDER THIS STEERING INFLUENCE THROUGH TAU 60, THEN SHIFT TO A WEST-NORTHWESTWARD TRACK AS THE RIDGE BUILDS AND MIGRATES WESTWARD. THE FORECAST TRACK SPEED HAS INCREASED DUE TO THE RECENT ACCELERATION OF TS 17W, WITH PASSAGE NORTH OF SAIPAN NOW EXPECTED AROUND 211400Z. AS FOR INTENSITY, THE SYSTEM IS EXPECTED TO SLOWLY INTENSIFY AS IT CONSOLIDATES OVER THE NEXT 12-24 HOURS, THEN EXPERIENCE AN EXTENDED PERIOD OF RAPID INTENSIFICATION TO A PEAK OF 120 KTS AROUND TAU 72. THIS PERIOD OF RI WILL BE FUELED BY VERY WARM (30-31 C) SEA SURFACE TEMPERATURES, HIGH OCEAN HEAT CONTENT, EXCELLENT OUTFLOW ALOFT, AND A LOW WIND SHEAR ENVIRONMENT. AFTER TAU 72, A GRADUAL WEAKENING TREND IS EXPECTED DUE TO A COMBINATION OF FACTORS THAT INCLUDE POTENTIAL EYEWALL REPLACEMENT CYCLES AND COOLER SEA SURFACE TEMPERATURES. MODEL DISCUSSION: MODEL TRACK GUIDANCE REMAINS IN GOOD AGREEMENT ABOUT THE NORTHWESTWARD TRACK OVER THE NEXT 72 HOURS, HOWEVER, THERE IS SOME UNCERTAINTY IN TRACK SPEED INTRODUCED BY AN ALONG-TRACK SPREAD OF OVER 100 NM AT THAT TIME. JGSM AND NAVGEM ARE CONSIDERED TO BE FAST OUTLIERS WHILE THE REMAINDER OF GUIDANCE IS MUCH CLOSER TOGETHER. AFTER TAU 72, TRACK …

95W (WP952026)

Type: TD Max Wind: 25 kt Min Pressure: 999 hPa Position: 19.4, 110.4 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.

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: SE (130°), 5.8 kt   |   Gust: 7.8 kt

Pressure: 30.05 rising   |   Air Temp: 86.0 °F

Water Temp: 87.8 °F   |   Dew Point: 77.7 °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.