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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.
ZCZC MIATCDEP4 ALL
TTAA00 KNHC DDHHMM
Tropical Storm Iselle Discussion Number 5
NWS National Hurricane Center Miami FL EP092026
800 AM PDT Mon Aug 24 2026
Despite being affected by moderate west-northwesterly shear,
Iselle's cloud pattern has continued to improve, with a core of very
deep convection that has now rotated over and north of the center,
and a deep convective band extending southward on the east side of
the cyclone. A 24/0903 UTC AMSR-2 pass also shows the improving
structure of the inner core. The latest subjective Dvorak
classification from TAFB is T3.5/55 kt, and objective satellite
intensity estimates range from 50 to 59 kt. The initial intensity
has been set at 55 kt for this advisory, in agreement with the
estimates.
The initial motion estimate is northwestward, or 310/11 kt. A
mid-level ridge north of Iselle is forecast to strengthen, causing
Iselle to turn west-northwestward on Tuesday, and that motion should
then continue through the end of the week. The latest NHC track
forecast is a little faster and to the left of the previous
forecast, and lies very close to the HFIP Corrected Consensus (HCCA)
and the Google DeepMind Ensemble Mean (GDMI).
Iselle remains over warm waters and within a moist environment.
However, SHIPS and UW-CIMSS both currently analyze 17 kt of vertical
wind shear. Water temperatures and moisture will remain quite
favorable for another 24 h, but the shear is forecast to increase to
at least 20 kt between the 12 to 24 h period. Given the recently
improving structure, the NHC forecast continues to call for
strengthening and system to become a hurricane in 12 to 24 h, which
is at the high end of the intensity model guidance suite. However,
given the increasing shear, there is some uncertainty as to whether
Iselle will become a hurricane. Beyond 24 h, gradually decreasing
ocean temperatures and moisture will lead to steady weakening, and
the NHC intensity forecast lies in the middle of the guidance
envelope from hour 48 onward. The latest ECMWF and GFS simulated
satellite imagery suggest that Iselle could become a remnant low as
early as Thursday. I have moved forward the forecast time for
Iselle becoming post-tropical to hour 96, but it's possible the
cyclone could lose its convection sooner than forecast. After that,
the models indicate the remnant low opening up into a trough by day
5.
FORECAST POSITIONS AND MAX WINDS
INIT 24/1500Z 18.5N 117.1W 55 KT 65 MPH
12H 25/0000Z 19.4N 118.3W 65 KT 75 MPH
24H 25/1200Z 20.5N 120.2W 65 KT 75 MPH
36H 26/0000Z 21.1N 122.1W 60 KT 70 MPH
48H 26/1200Z 21.5N 123.8W 50 KT 60 MPH
60H 27/0000Z 22.0N 125.6W 40 KT 45 MPH
72H 27/1200Z 22.5N 127.6W 35 KT 40 MPH
96H 28/1200Z 23.1N 131.9W 30 KT 35 MPH...POST-TROP/REMNT LOW
120H 29/1200Z...DISSIPATED
$$
Forecaster Hagen
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.
WDPN31 PGTW 241500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 17W (SAUDEL) WARNING NR 025//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 24.9N 133.5E
INITIAL INTENSITY: 100 KTS
GEOGRAPHIC REFERENCE: 323 NM EAST-SOUTHEAST OF KADENA
MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 12 KTS
SIGNIFICANT WAVE HEIGHT: 46 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS TYPHOON 17W
(SAUDEL) HAVING BECOME MUCH MORE IRREGULAR OVER THE PAST 6 HOURS WITH
A CLEAR WEAKNESS IN THE NORTHWESTERN QUADRANT OF THE EYEWALL AND A
COOLING EYE. THERE APPEARS TO BE SOME DRY AIR INTRUDING INTO THE
VORTEX WITHIN THE WESTERN SEMICIRCLE AND NORTHWESTERLY SHEAR IS
STARTING TO INCREASE. A 240914Z RCM-1 SAR PASS REVEALED A VMAX OF 100
KTS IN THE EASTERN PORTION OF THE EYEWALL. THE SAR ALSO SHOWED THAT
THE WIND FIELD HAS BECOME SOMEWHAT ASYMMETRIC WITH THE STRONGEST WINDS
LOCATED IN THE EASTERN AND NORTHERN PORTIONS OF THE CIRCULATION. A
240934Z GMI 37 GHZ MICROWAVE IMAGE CONFIRMED THAT THE INNER CORE HAS
BECOME A BIT DISORGANIZED WITH A FRAGMENTED MICROWAVE EYE FEATURE. THE
INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE EYE IN
ANIMATED EIR AND EXTRAPOLATION FROM THE GMI MICROWAVE IMAGE. THE
INITIAL INTENSITY OF 100 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED
ON A COMBINATION OF THE AFOREMENTIONED SAR DATA AND THE INTENSITY
ESTIMATES LISTED BELOW. ENVIRONMENTAL ANALYSIS INDICATES THAT 17W IS
NOW IN A MARGINALLY FAVORABLE ENVIRONMENT CHARACTERIZED BY STRONG
RADIAL OUTFLOW ALOFT, 10-15 KTS NORTHWESTERLY SHEAR, DRY AIR, AND WARM
(28-29 C) SEA SURFACE TEMPERATURES.
INITIAL WIND RADII BASIS: 241123Z METOP-B ASCAT SCATTEROMETER DATA
CURRENT STEERING MECHANISM: THE SOUTHWESTERN FLANK OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) WHICH EXTENDS FROM SOUTHERN JAPAN
SOUTHEASTWARD TO A POINT NORTHEAST OF GUAM.
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T5.5 - 102 KTS
RJTD: T6.0 - 115 KTS
RCTP: T6.0 - 115 KTS
KNES: T5.5 - 102 KTS
CIMSS ADT: 104 KTS AT 241200Z
CIMSS AIDT: 102 KTS AT 241200Z
CIMSS D-MINT: 98 KTS AT 241130Z
CIMSS D-PRINT: 107 KTS AT 241200Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE
VWS: 10-15 KTS
SST: 28-29 CELSIUS
OUTFLOW: STRONG RADIAL
OTHER FACTORS: SLIGHT DRY AIR ENTRAINMENT FROM THE WEST
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 17W IS FORECAST TO CONTINUE TRACKING WEST-
NORTHWESTWARD THROUGH TAU 36, PASSING JUST NORTH OF OKINAWA AT AROUND
TAU 30. NEAR TAU 36, 17W WILL APPROACH A WEAKNESS IN THE STEERING
RIDGE TO THE NORTH, CAUSING IT TO SLOW DOWN MARKEDLY AS THE PRIMARY
STEERING MECHANISM SHIFTS TO A SUBTROPICAL RIDGE (STR) CENTERED OVER
EASTERN CHINA. TRACK SPEEDS ARE EXPECTED TO REMAIN SLOW THROUGH TAU 60
BEFORE THE STEERING GRADIENT BECOMES STRONGER. AFTER TAU 60, THE SPEED
OF ADVANCE OF 17W IS FORECAST TO BEGIN INCREASING WITH A SOUTHWESTWARD
TRAJECTORY AS THE SYSTEM TRACKS ALONG THE SOUTHEASTERN PERIPHERY OF
THE STR OVER CHINA THROUGH THE REMAINDER OF THE FORECAST PERIOD.
LANDFALL OVER EASTERN CHINA IS CURRENTLY FORECAST TO OCCUR JUST BEFORE
TAU 96. IN TERMS OF INTENSITY, 17W IS FORECAST TO CONTINUE GRADUALLY
WEAKENING UNDER THE EFFECTS OF INCREASING NORTHWESTERLY SHEAR AND DRY
AIR ENTRAINMENT. ADDITIONALLY, THE UPPER-LEVEL TROUGH CURRENTLY TO THE
WEST OF THE SYSTEM IS EXPECTED TO MOVE WESTWARD AND FILL, REDUCING
OUTFLOW ALOFT. AT AROUND TAU 72, NORTHEASTERLY SHEAR WILL GREATLY
INCREASE, INDUCED BY THE STRONG RIDGE OVER EASTERN CHINA CAUSING A
MORE RAPID RATE OF W…
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 241500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 18W (NARRA) WARNING NR
016//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 19.6N 107.3E
INITIAL INTENSITY: 40 KTS
GEOGRAPHIC REFERENCE: 115 NM SOUTHEAST OF HANOI, VIETNAM
MOVEMENT PAST 6 HOURS: SOUTHWARD AT 03 KTS
SIGNIFICANT WAVE HEIGHT: 13 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS TROPICAL
STORM 18W (NARRA) WITH WARMING CLOUD TOPS THAT ARE BEGINNING TO BE
HEAVILY SHEARED OFF TO THE SOUTHWEST. A 241107Z GMI 89 GHZ MICROWAVE
IMAGE REVEALED MINIMAL CONVECTIVE STRUCTURE TO THE WEST OF THE LOW-
LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS PLACED WITH
MEDIUM CONFIDENCE BASED ON THE GMI IMAGE AND ANIMATED EIR IMAGERY. THE
INITIAL INTENSITY OF 40 KTS IS ASSESSED WIT MEDIUM CONFIDENCE BASED ON
THE AGENCY DVORAK AND CIMSS INTENSITY ESTIMATES LISTED BELOW.
ENVIRONMENTAL ANALYSIS INDICATES THAT 18W IS NOW IN A MARGINAL
ENVIRONMENT CHARACTERIZED BY MODERATE EQUATORWARD OUTFLOW ALOFT,
MODERATE TO HIGH (25-30 KTS) VERTICAL WIND SHEAR, DRY AIR ENTRAINMENT,
AND WARM (29-30 C) SEA SURFACE TEMPERATURES
INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK
CURRENT STEERING MECHANISM: A COMPETING STEERING ENVIRONMENT WITH A
NEAR-EQUATORIAL RIDGE (NER) TO THE SOUTH AND A SUBTROPICAL RIDGE (STR)
TO THE NORTH
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.5 - 35 KTS
RJTD: T2.0 - 30 KTS
KNES: T2.5 - 35 KTS
CIMSS ADT: 35 KTS AT 241210Z
CIMSS AIDT: 36 KTS AT 241210Z
CIMSS D-MINT: 37 KTS AT 241139Z
CIMSS D-PRINT: 39 KTS AT 241210Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINAL
VWS: 25-30 KTS
SST: 29-30 CELSIUS
OUTFLOW: MODERATE EQUATORWARD
OTHER FACTORS: DRY AIR ENTRAINMENT FROM THE EAST
ANALYSIS CONFIDENCE:
INITIAL POSITION: MEDIUM
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 18W IS FORECAST TO BEGIN TRACKING SLOWLY
EASTWARD OVER THE NEXT 12 HOURS AS THE STR RIDGE TO THE NORTH WEAKENS
AND THE NER TO THE SOUTH BECOMES THE PRIMARY STEERING MECHANISM. AFTER
TAU 12, 18W IS EXPECTED TO TURN POLEWARD, USHERED BY THE NER BUILDING
TO THE SOUTHEAST OF THE SYSTEM. LANDFALL WITHIN SOUTHERN CHINA IS
FORECAST TO OCCUR AROUND TAU 48 NEAR THE LEIZHOU PENINSULA. REGARDING
INTENSITY, 18W IS FORECAST TO BEGIN WEAKENING THROUGHOUT ITS APPROACH
TO THE COAST OF CHINA AS EAST-NORTHEASTERLY SHEAR AND DRY AIR
ENTRAINMENT BEGINS TO FURTHER INCREASE. AFTER LANDFALL, TERRAIN
INTERACTION WILL QUICKLY WEAKEN THE VORTEX WITH DISSIPATION
ANTICIPATED TO OCCUR NO LATER THAN TAU 60 AS THE REMNANT VORTEX TRACKS
FURTHER INLAND.
MODEL DISCUSSION: MODEL TRACK GUIDANCE CONTINUES TO BE IN BETTER
AGREEMENT THIS MODEL RUN WITH THE ONLY OUTLIER BEING GALWEM, WHICH
TRACK THE SYSTEM MUCH MORE QUICKLY INLAND THAN THE REMAINDER OF
GUIDANCE. THE JTWC TRACK FORECAST IS PLACED CLOSE TO THE MULTI-MODEL
CONSENSUS WITH MEDIUM CONFIDENCE. INTENSITY GUIDANCE AGREES ON STEADY
WEAKENING THROUGHOUT THE FORECAST PERIOD WITH NO NOTABLE OUTLIERS
PRESENT. AS A RESULT, THE JTWC INTENSITY FORECAST IS ALSO PLACED NEAR
THE CONSENSUS WITH MEDIUM CONFIDENCE.
FORECAST CONFIDENCE:
TRACK 00-72 HR: MEDIUM
INTENSITY 00-72 HR: MEDIUM//
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.
WDPN33 PGTW 241500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 19W (ATSANI) WARNING
NR 009//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 16.7N 138.3E
INITIAL INTENSITY: 30 KTS
GEOGRAPHIC REFERENCE: 514 NM SOUTH-SOUTHWEST OF IWO TO
MOVEMENT PAST 6 HOURS: NORTH-NORTHEASTWARD AT 06 KTS
SIGNIFICANT WAVE HEIGHT: 12 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS TROPICAL
DEPRESSION (TD) 19W (ATSANI) WITH A NEARLY FULLY EXPOSED LOW-LEVEL
CIRCULATION CENTER (LLCC) WITH A RECENT CONVECTIVE FLARE-UP ALONG THE
SOUTHWESTERN PERIPHERY. THE SYSTEM HAS SLOWED DOWN OVER THE LAST 6
HOURS, WHILE A SUBTROPICAL RIDGE (STR) CENTERED TO THE NORTHEAST
ASSUMED PRIMARY STEERING. CONSEQUENTLY, A NORTHWARD TRANSLATION VECTOR
IS INITIATING TO DOMINATE THE DIRECTION OF MOTION. A BINARY FUJIWHARA
INTERACTION REMAINS ACTIVE AS THE DISTANCE BETWEEN TD 19W AND TYPHOON
(TY) 17W REMAINS WITHIN THE CRITICAL DISTANCE THRESHOLD. HIGH
CONFIDENCE ENVELOPS THE INITIAL POSITION COORDINATES, DEDUCED VIA
SHORTWAVE INFRARED IMAGERY DEPICTING THE NEARLY FULLY UNVEILED LLCC.
THE METEOROLOGICAL ENVIRONMENT REMAINS MARGINALLY UNFAVORABLE FOR
FURTHER INTENSIFICATION. ALTHOUGH SEA SURFACE TEMPERATURES (SST)
REMAIN VERY WARM (29-30 C), THE EQUATORWARD OUTFLOW CHANNEL PROVIDES
MINIMAL ASSISTANCE. SIMULTANEOUSLY, HIGH (25-30 KTS) NORTHEASTERLY
VERTICAL WIND SHEAR (VWS) ARRESTS ANY CENTRAL CONVECTIVE STRUCTURING.
MOREOVER, ALTHOUGH TROPOSPHERIC MOISTURE PERSISTS TO THE WEST,
UNFAVORABLE MID-LEVEL DRY-AIR ADVECTION CONTINUES TO WRAP AROUND AND
INTO THE INNER VORTEX CORE. THE INITIAL INTENSITY OF 30 KTS IS
ASSESSED WITH HIGH CONFIDENCE BASED ON A 241144Z METOP-C ASCAT PASS
SHOWING WIND SPEED MAXIMA OF 25 KTS, WITH VERY FEW 30 KTS WIND BARBS.
ADDITIONALLY, AGENCY DVORAK ESTIMATES ARE IN PERFECT T2.0 AGREEMENT.
INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND
RADII).
CURRENT STEERING MECHANISM: SOUTHEASTWARD EXTENSION OF A SUBTROPICAL
RIDGE CENTERED TO THE NORTHEAST
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.0 - 30 KTS
RJTD: T2.0 - 30 KTS
RCTP: T2.0 - 30 KTS
KNES: T2.0 - 30 KTS
CIMSS ADT: 31 KTS AT 241210Z
CIMSS AIDT: 34 KTS AT 241210Z
CIMSS D-MINT: 33 KTS AT 241133Z
CIMSS D-PRINT: 26 KTS AT 241210Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY
UNFAVORABLE
VWS: 25-30 KTS
SST: 29-30 CELSIUS
OUTFLOW: WEAK EQUATORWARD
OTHER FACTORS: PERSISTENT DRY AIR ENTRAINMENT
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: HIGH
INITIAL WIND RADII: NOT APPLICABLE
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE
FORECAST FROM THE PREVIOUS WARNING.
FORECAST DISCUSSION: TD 19W IS FORECAST TO BEGIN TURNING NORTHWARD
AND EVENTUALLY NORTHWESTWARD OVER THE NEXT 12 TO 24 HOURS, ULTIMATELY
RETREATING INTO THE HIGHLY SHEARED WAKE OF TYPHOON 17W. THIS EVOLUTION
MARKS THE ONSET OF THE TERMINAL WEAKENING OF TD ATSANI, DICTATED BY
INCREASINGLY HOSTILE NORTHEASTERLY VWS AND RELENTLESS CORE DRY-AIR
ENTRAINMENT. CONSEQUENTLY, THE SYSTEM WILL SUSTAIN 30 KTS ONLY
TRANSIENTLY. STRUCTURAL DEGRADATION WILL BE RAPID AS THE LLCC LOSES
ITS SYMMETRIC DYNAMICS AND OPENS UP, PARTICULARLY ACROSS THE WESTERN
SEMICIRCLE. COMPLETE DISSIPATION OVER WATER IS PROJECTED BY TAU 36.
MODEL DISCUSSION: NUMERICAL MODEL TRACK PREDICTION SPREAD EXHIBITS
HIGH CONSISTENCY, DEPICTING A TIGHT 90 NM CROSS-TRACK DISPERSION
ENVELOPE THROUGH TAU 36. ALONG-TRACK UNCERTAINTY IS MODERATE,
CONSTRAINED TO A 190 NM SPREAD SEPARATING THE FASTEST JGSM AND
DETERMINISTIC ECMWF TRACKERS AND THE SLOWEST UKMET AND ECMWF ENSEMBLE
PREDICTIONS. THE OFFICIAL JTWC TRACK FORECAST IS POSITIONED ALONG THE
EASTER…
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: NE (40°), 1.9 kt | Gust: 3.9 kt
Pressure: 30.03 | Air Temp: 86.5 °F
Water Temp: 87.1 °F | Dew Point: 78.3 °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.
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.
