🚨 Montgomery: None 🚨 Cross Sound; Cape Edgecumbe to Cape Spencer out to 15 NM; Cape Spencer to Cape Fairweather out to 15 NM: Special Marine Warning issued September 20 at 9:33AM AKDT until September 20 at 10:00AM AKDT by NWS Juneau AK 🚨 Buchanan; Delaware; Dubuque; Benton; Linn; Jones; Jackson; Iowa; Johnson; Cedar; Clinton; Muscatine; Scott; Keokuk; Washington; Louisa; Jo Daviess; Stephenson; Carroll; Whiteside; Rock Island; Henry; Bureau; Putnam; Mercer: Flood Watch issued September 20 at 12:31PM CDT until September 20 at 1:00PM CDT by NWS Quad Cities IA IL 🚨 Morgan; Washington: Special Weather Statement issued September 20 at 1:28PM EDT by NWS Charleston WV 🚨 Frederick Sound: Marine Weather Statement issued September 20 at 9:22AM AKDT by NWS Juneau AK 🚨 Madison: Special Weather Statement issued September 20 at 1:21PM EDT by NWS Tallahassee FL 🚨 Icy Strait; Cross Sound; Cape Edgecumbe to Cape Spencer out to 15 NM; Cape Spencer to Cape Fairweather out to 15 NM: Marine Weather Statement issued September 20 at 9:19AM AKDT by NWS Juneau AK 🚨 Straits of Florida from Craig Key to west end of Seven Mile Bridge 20 to 60 NM out: Marine Weather Statement issued September 20 at 1:18PM EDT by NWS Key West FL 🚨 Athens, OH; Gallia, OH; Meigs, OH; Washington, OH; Jackson, WV; Mason, WV; Wood, WV: Flood Warning issued September 20 at 1:17PM EDT until September 20 at 4:00PM EDT by NWS Charleston WV 🚨 Allegheny, PA; Washington, PA; Ohio, WV: Flood Warning issued September 20 at 1:17PM EDT until September 20 at 4:00PM EDT by NWS Pittsburgh PA
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 MIATCDAT1 ALL
TTAA00 KNHC DDHHMM
Tropical Storm Fay Discussion Number 5
NWS National Hurricane Center Miami FL AL062026
300 PM GMT Sun Sep 20 2026
Deep convection continues to build near the center of Fay over the
last several hours. The current objective intensity estimates from
UW-CIMSS are in the range of 39-52 kt, and the most recent TAFB
Dvorak fix was a T3.0/45 kt. In addition, there was an ASCAT pass
that showed a peak wind vector of 43 kt. Given the uncertainties
due to undersampling, the initial intensity for the storm has been
raised to 50 kt. The cyclone continues to remain very compact with
its tropical-storm-force winds estimated to extend out to about 40
n mi.
Both a relatively moist environment and positive interactions
with an approaching mid- to upper-level trough should allow Fay to
further intensify for the next 12 to 24 hours. After the trough
lifts on Monday, the increase in wind shear and dry air should lead
to a gradual weakening of the cyclone. The current NHC forecast
calls for Fay to become a post-tropical remnant low by Tuesday and
then dissipate by the end of the week. The official intensity
forecast is a little higher than the model guidance in the short
term to account for the storm's structure being more improved and
the expected baroclinic support from the trough. This small system
could approach hurricane strength later today or tonight.
Fay is slowly moving off to the northeast, with the initial motion
estimated around 010/5 kt. This general motion should continue for
the rest of the day. However, a low- to mid-level ridge is expected
to build to the north of the storm by Monday, which will cause Fay
to turn southwestward and gradually accelerate in that direction
over the course of the forecast period. The current NHC track
forecast is similiar to the previous track forecast with a few
minor adjustments and remains in good agreement with HCCA and
GDMI.
FORECAST POSITIONS AND MAX WINDS
INIT 20/1500Z 34.1N 33.0W 50 KT 60 MPH
12H 21/0000Z 34.3N 32.6W 60 KT 70 MPH
24H 21/1200Z 33.9N 32.4W 50 KT 60 MPH
36H 22/0000Z 32.9N 32.9W 45 KT 50 MPH
48H 22/1200Z 31.7N 34.2W 35 KT 40 MPH
60H 23/0000Z 30.6N 35.9W 30 KT 35 MPH...POST-TROP/REMNT LOW
72H 23/1200Z 29.8N 37.7W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 24/1200Z 28.8N 41.1W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 25/1200Z...DISSIPATED
$$
Forecaster Katz/Pasch
NNNN
ZCZC MIATCDEP1 ALL
TTAA00 KNHC DDHHMM
Tropical Storm Odalys Discussion Number 2
NWS National Hurricane Center Miami FL EP162026
800 AM PDT Sun Sep 20 2026
Deep convection has been increasing in association with Odalys
this morning, with cloud tops colder than -80 deg C near the
estimate center location. Some banding features are beginning to
develop over the southern semicircle of the system. Upper-level
outflow is limited to the north of the storm, however. The current
intensity is set at 40 kt for this advisory, which is a blend of
subjective and objective Dvorak estimates.
The center is not easy to locate, but my best estimate of initial
motion is west-northwestward, or around 285/8 kt. Odalys should
turn northwestward as it moves on the southwestern side of a
narrow and weakening mid-level ridge to its northeast. After
about 48 hours, the system should slow and turn northeastward
and eastward in response to the ridge weakening and a
mid-tropospheric trough moving over southern California and Baja
California. Later in the forecast period, the cyclone should
move generally northeastward along the northwest side of a
mid-level ridge. However there is significant uncertainty in
the 3-5 day track of Odalys due its potential interaction with a
developing tropical cyclone to its east. The official track
forecast is fairly close to the lastest corrected model consensus,
HCCA, prediction.
Odalys should be in an environment conducive for strengthening
during the next few days, with very warm waters, low to moderate
vertical wind shear, and high low- to mid-level humidity.
Therefore gradual strengthening is expected during the next couple
of days, and the official forecast is close to the latest
Decay-SHIPS model guidance. Later in the forecast period, the
system may encounter a little drier air and its intensity become
hindered by its interaction with the developing tropical cyclone
closer to the coast of Mexico.
FORECAST POSITIONS AND MAX WINDS
INIT 20/1500Z 11.1N 125.5W 40 KT 45 MPH
12H 21/0000Z 12.1N 126.8W 50 KT 60 MPH
24H 21/1200Z 13.3N 128.1W 60 KT 70 MPH
36H 22/0000Z 14.1N 129.0W 70 KT 80 MPH
48H 22/1200Z 14.5N 129.2W 75 KT 85 MPH
60H 23/0000Z 14.8N 128.4W 75 KT 85 MPH
72H 23/1200Z 14.9N 127.7W 75 KT 85 MPH
96H 24/1200Z 15.5N 126.2W 75 KT 85 MPH
120H 25/1200Z 16.8N 124.5W 65 KT 75 MPH
$$
Forecaster Pasch
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 201500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 24W (DUJUAN) WARNING NR
021//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 30.4N 137.6E
INITIAL INTENSITY: 60 KTS
GEOGRAPHIC REFERENCE: 312 NM SOUTH-SOUTHWEST OF YOKOSUKA, JAPAN
MOVEMENT PAST 6 HOURS: NORTHWARD AT 06 KTS
SIGNIFICANT WAVE HEIGHT: 28 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS TROPICAL
STORM (TS) 24W (DUJUAN) STRUGGLING TO CONSOLIDATE ITS DEEP CONVECTION,
AS A SIGNIFICANT AMOUNT OF DRY AIR IS BEING INJECTED INTO THE CORE OF
THE VORTEX. THE SYSTEM MAINTAINS A TIGHT LOW-LEVEL CIRCULATION CENTER
(LLCC), WHICH IS IDENTIFIED WITH HIGH CONFIDENCE UTILIZING SATELLITE
IMAGERY AND EXTRAPOLATION FROM A 200855Z WSFM MWI 37 GHZ MICROWAVE
PASS. INTENSITY IS ALSO ASSESSED WITH HIGH CONFIDENCE BASED ON A
COHERENT FUSION OF SUBJECTIVE SATELLITE DVORAK FIXES AND AUTOMATED
OBJECTIVE ESTIMATES LISTED BELOW. ASIDE FROM THE DRY AIR, OTHER
ENVIRONMENTAL PARAMETERS REMAIN MOSTLY FAVORABLE FOR INTENSIFICATION.
THE POLEWARD OUTFLOW CHANNEL REMAINS ROBUST, SEA SURFACE TEMPERATURES
(SST) ARE WARM (28-29 C), AND VERTICAL WIND SHEAR (VWS) IS LOW (10-15
KTS).
INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK AND A PARTIAL
201205Z METOP-B ASCAT PASS
CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) CENTERED TO THE
EAST
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T4.0 - 65 KTS
RJTD: T4.0 - 65 KTS
RCTP: T4.0 - 65 KTS
CIMSS ADT: 51 KTS AT 201130Z
CIMSS AIDT: 48 KTS AT 201130Z
CIMSS D-PRINT: 66 KTS AT 201230Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE
VWS: 10-15 KTS
SST: 28-29 CELSIUS
OUTFLOW: STRONG POLEWARD
OTHER FACTORS: DRY AIR ENTRAINMENT
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: HIGH
INITIAL WIND RADII: MEDIUM
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.
FORECAST DISCUSSION: THE TRANSLATION VECTOR OF TS 24W IS EXPECTED TO
CONTINUE TURNING TOWARD THE NORTHEAST WITHIN THE COMING 12 HOURS AND
THROUGHOUT THE CURRENT FORECAST PERIOD, AS THE CYCLONE TRANSITS ALONG
THE NORTHWESTERN PERIPHERY OF THE STR ANCHORED TO THE EAST. THE
CLOSEST POINT OF APPROACH (CPA) TO YOKOSUKA, JAPAN, IS ESTIMATED AT 80
NM, COINCIDING WITH THE TIMELINE JUST BEFORE TAU 24. BETWEEN TAUS 24
AND 36, SLIGHT DYNAMIC DEEPENING TO A PEAK INTENSITY OF 70 KTS IS
PROJECTED UNDER A MARGINALLY FAVORABLE ENVIRONMENT, AIDED BY THE
CYCLONE TEMPORARILY COCOONING FROM HOSTILE DRY AIR WHILE PROPAGATING
OVER THE TAIL END OF THE WARM KUROSHIO CURRENT AND HARNESSING ENHANCED
POLEWARD OUTFLOW DYNAMICS. SHORTLY AFTER, HOWEVER, THE ONSET OF
EXTRATROPICAL TRANSITION (ETT) WILL EMERGE AS WATERS SHARPLY COOL,
HOSTILE DRY-AIR ENTRAINMENT INTENSIFIES, AND VERTICAL WIND SHEAR
ACCELERATES TO 30+ KTS AROUND TAU 48. INTEGRATING RAPIDLY INTO THE
MID-LATITUDE WESTERLIES, TS DUJUAN WILL COMPLETE THE TRANSITION PRIOR
TO TAU 60.
MODEL DISCUSSION: IN TERMS OF TRACK OUTLOOK, EXCELLENT AGREEMENT
ENVELOPS THE DYNAMICAL MODEL PREDICTIONS, DEPICTING A TIGHT 20 NM
SPREAD AT THE CPA TO YOKOSUKA, BALANCED BY A MODERATE ALONG-TRACK
TIMING VARIABILITY OF 80 NM. BASED ON THIS CONGRUENT GROUPING, THE
OFFICIAL JTWC TRACK PROGNOSIS IS POSITIONED CLOSE TO THE MULTI-MODEL
CONSENSUS WITH HIGH CONFIDENCE. REGARDING INTENSITY GUIDANCE, THE
DYNAMICAL ENVELOPE PROJECTS A BRIEF STEADY-STATE RUN OVER THE COMING
12 HOURS, TRANSITIONING TO SLIGHT INTENSIFICATION THEREAFTER, THOUGH
THE INTENSITY PROJECTION UNCERTAINTY ENVELOPE WIDENS TO A 25 KTS
SPREAD (SPREADING FROM 50 TO 75 KTS) BY TAU 36. WHILE STATISTICAL-
DYNAMICAL SCENARIOS PERSISTENTLY PROJECT STEADY WEAKENING, THE
DYNAMICAL M…
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: E (80°), 7.8 kt | Gust: 9.7 kt
Pressure: 29.94 | Air Temp: 85.1 °F
Water Temp: 87.3 °F | Dew Point: 78.3 °F
Swell: 1.6 ft | Wind Wave: 0.7 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.
