🚨 Montgomery: None 🚨 Beaufort; Jones; Pamlico; Northern Craven; Southern Craven; West Carteret; Inland Onslow; Coastal Onslow: Special Weather Statement issued September 21 at 7:32AM EDT by NWS Newport/Morehead City NC 🚨 King, TX: Flood Advisory issued September 21 at 6:31AM CDT until September 21 at 8:00AM CDT by NWS Lubbock TX 🚨 Coastal waters from Altamaha Sound to Fernandina Beach FL out 20 NM: Marine Weather Statement issued September 21 at 7:26AM EDT by NWS Jacksonville FL 🚨 Zapata; Jim Hogg; Brooks; Inland Kenedy; Starr; Southern Hidalgo; Inland Willacy; Inland Cameron; Coastal Kenedy; Northern Hidalgo; Coastal Willacy; Coastal Cameron: Special Weather Statement issued September 21 at 6:23AM CDT by NWS Brownsville TX 🚨 Houston, MN: Flood Warning issued September 21 at 6:19AM CDT until September 22 at 4:00PM CDT by NWS La Crosse WI 🚨 Eastern Glacier, Western Toole, and Central Pondera; Eastern Toole and Liberty; Hill County; Northern Blaine County; Western and Central Chouteau County; Bears Paw Mountains and Southern Blaine; Judith Basin County and Judith Gap; Fergus County below 4500ft; Meagher County Valleys: Special Weather Statement issued September 21 at 5:18AM MDT by NWS Great Falls MT 🚨 Cheyenne; Rawlins; Decatur; Norton; Dundy; Hitchcock; Red Willow: Dense Fog Advisory issued September 21 at 6:15AM CDT until September 21 at 10:00AM CDT by NWS Goodland KS 🚨 Chesapeake Bay from Pooles Island to Sandy Point MD; Chesapeake Bay from Sandy Point to North Beach MD; Chesapeake Bay from North Beach to Drum Point MD; Chesapeake Bay from Drum Point MD to Smith Point VA; Chester River to Queenstown MD; Eastern Bay; Choptank River to Cambridge MD and the Little Choptank River; Tangier Sound and the inland waters surrounding Bloodsworth Island: Small Craft Advisory issued September 21 at 7:14AM EDT until September 21 at 12:00PM EDT by NWS Baltimore MD/Washington DC 🚨 Chesapeake Bay from Pooles Island to Sandy Point MD; Chesapeake Bay from Sandy Point to North Beach MD; Chesapeake Bay from North Beach to Drum Point MD; Chesapeake Bay from Drum Point MD to Smith Point VA; Chester River to Queenstown MD; Eastern Bay; Choptank River to Cambridge MD and the Little Choptank River; Tangier Sound and the inland waters surrounding Bloodsworth Island: Small Craft Advisory issued September 21 at 7:14AM EDT until September 23 at 6:00AM EDT by NWS Baltimore MD/Washington DC
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 8
NWS National Hurricane Center Miami FL AL062026
900 AM GMT Mon Sep 21 2026
Fay is now feeling the effects of strong vertical wind shear.
Satellite imagery indicates that the circulation has become
significantly vertical tilted, with the low-level center now well
north-northwest of the mid-level center. The initial intensity is
nudged down to 55 kt, which lies at the high end of the latest
satellite intensity estimates.
Continued strong northerly vertical wind shear, along with
intrusions of dry air should cause Fay to steadily weaken over the
next few days. In fact, simulated satellite images from the GFS and
ECMWF models show deep convection completely dissipating within the
next 24 hours due to the harsh atmospheric conditions. Based on the
latest guidance and satellite trends, the new forecast calls for a
faster rate of weakening, with the transition to a remnant low now
expected by 48 hours and dissipation in 4-5 days. This forecast lies
near the middle of the guidance envelope.
Fay appears to have turned southward at a slow pace, as expected, as
the mid- to upper-level trough over the north Atlantic lifts out. A
faster southwestward motion is forecast over the next few days as a
low- to mid-level ridge becomes established to the northeast of the
cyclone. This pattern should keep the system over the open Atlantic
through dissipation later in the week. Little change was made to the
previous track forecast, and this prediction is in best agreement
with the Google DeepMind ensemble mean and HCCA.
FORECAST POSITIONS AND MAX WINDS
INIT 21/0900Z 33.8N 32.1W 55 KT 65 MPH
12H 21/1800Z 33.2N 32.3W 45 KT 50 MPH
24H 22/0600Z 32.3N 33.2W 40 KT 45 MPH
36H 22/1800Z 31.2N 34.9W 35 KT 40 MPH
48H 23/0600Z 30.4N 36.7W 30 KT 35 MPH...POST-TROP/REMNT LOW
60H 23/1800Z 29.8N 38.4W 30 KT 35 MPH...POST-TROP/REMNT LOW
72H 24/0600Z 29.6N 40.1W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 25/0600Z 29.5N 43.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 26/0600Z...DISSIPATED
$$
Forecaster Cangialosi
NNNN
ZCZC MIATCDEP1 ALL
TTAA00 KNHC DDHHMM
Tropical Storm Odalys Discussion Number 5
NWS National Hurricane Center Miami FL EP162026
200 AM PDT Mon Sep 21 2026
Odalys continues to be an asymmetric tropical cyclone this morning,
with deep convection primarily confined to the southern and eastern
semicircles. The low-level center was exposed for much of the
evening. However, over the past couple of hours, a new burst of deep
convection has developed near the center. A Metop-B scatterometer
pass at 0455 UTC revealed peak winds of only 32 kt. Meanwhile, the
latest subjective and objective satellite intensity estimates range
from 39 to 45 kt. Blending the scatterometer data with the higher
satellite estimates and the subsequent convective burst near the
center, the initial intensity is lowered to 40 kt for this advisory.
The initial motion is estimated to be northwestward, or 310/11 kt,
and this general motion should continue through tonight. A mid- to
upper-level trough is expected to move into the eastern Pacific
toward the southwest U.S. coast and the Baja California peninsula.
This will cause a sharp eastward turn, steering the system
east-northeastward to northeastward through the middle of the week
between the flow of the trough and a mid-level ridge situated
between Odalys and Tropical Storm Polo. The latest NHC track
forecast has been shifted to the right of the previous forecast,
and lies near the HCCA and GDMI track aids.
Odalys will continue to deal with vertical wind shear over the next
day or so. Afterward, the guidance suggests the shear should relax
slightly while the cyclone remains over warm sea surface
temperatures and within a moist environment. This should allow for
some gradual strengthening during the next few days. By the middle
to latter portion of the forecast period, the latest SHIPS guidance
shows the system moving into a drier mid-level environment, with
vertical wind shear expected to increase again. In response to
these less favorable conditions, several intensity models no longer
show Odalys reaching hurricane strength. Although Odalys is still
forecast to become a hurricane, the updated NHC intensity forecast
lies near the higher end of the guidance envelope, closely following
the HCCA consensus aid, and is slightly lower than the previous
forecast.
FORECAST POSITIONS AND MAX WINDS
INIT 21/0900Z 13.5N 128.7W 40 KT 45 MPH
12H 21/1800Z 14.4N 129.7W 45 KT 50 MPH
24H 22/0600Z 15.2N 130.3W 45 KT 50 MPH
36H 22/1800Z 15.4N 130.0W 50 KT 60 MPH
48H 23/0600Z 15.5N 129.1W 55 KT 65 MPH
60H 23/1800Z 15.6N 128.0W 60 KT 70 MPH
72H 24/0600Z 15.9N 126.8W 65 KT 75 MPH
96H 25/0600Z 17.2N 124.5W 70 KT 80 MPH
120H 26/0600Z 18.8N 122.6W 60 KT 70 MPH
$$
Forecaster Kelly
NNNN
ZCZC MIATCDEP2 ALL
TTAA00 KNHC DDHHMM
Tropical Storm Polo Discussion Number 3
NWS National Hurricane Center Miami FL EP172026
300 AM CST Mon Sep 21 2026
Deep convection associated with Polo has been gradually increasing
over the past several hours. A recent GMI microwave pass indicates
that Polo is developing a small core, which is an early indication
that significant strengthening could be beginning. The latest
satellite intensity estimates range from 35 to 45 kt, and based on
that data and an earlier ASCAT pass, the initial intensity is
increased to 40 kt.
Environmental conditions appear very conducive for strengthening
with the vertical wind shear expected to be less than 10 kt,
mid-level humidities near or above 70 percent, and SSTs above 30 C
during the next several days. These conditions, along with Polo's
improving and compact structure, support rapid intensification. In
fact, the SHIPS Rapid Intensification indices indicates that there
is a near 90 percent chance of an increase in winds of at least 55
kt over the next 48 hours. The NHC intensity forecast is quite
aggressive and calls for rapid intensification, and shows Polo
becoming a hurricane later today and a major hurricane on Tuesday.
This prediction is higher than the previous one, but below the
latest HCCA guidance which shows Polo reaching category 5 status in
about 48 hours.
The storm will likely drift eastward or southeastward during the
next day or so in weak steering currents. However, a sharp turn to
the west-northwest or northwest is expected by late Tuesday when a
mid-level ridge becomes established to the northeast of Polo. This
pattern should bring the core of the storm near the coast of
southwestern Mexico on Wednesday and Thursday, and then well south
of the Baja California Peninsula on Friday. There is a very large
spread in the model solutions in where, when, and how sharply Polo
makes the turn. The GFS model is on the far south side of the
guidance envelope while the Google DeepMind ensemble mean is on the
northern edge. The NHC track forecast has been nudged northward, and
is in best agreement with the corrected consensus HCCA model. It
should be noted that given the complex steering pattern and model
spread, confidence in the details of the track forecast is quite
low.
Key Messages:
1. Heavy rainfall associated with Tropical Storm Polo will impact
coastal portions of southwest Mexico this week. This rainfall may
produce life-threatening flooding and mudslides, especially in areas
of steep terrain.
2. Polo is forecast to strengthen to a major hurricane while it
moves closer to the coast of southwestern Mexico during the next few
days. Although the core of the hurricane is forecast to stay
offshore, it is too soon to determine the exact location or
magnitude of impacts. Residents in southwestern Mexico should
closely monitor its progress and updates to the forecast. A Tropical
Storm Watch has been issued for portions of southwestern Mexico.
FORECAST POSITIONS AND MAX WINDS
INIT 21/0900Z 15.5N 103.8W 40 KT 45 MPH
12H 21/1800Z 15.5N 103.1W 60 KT 70 MPH
24H 22/0600Z 15.3N 102.5W 80 KT 90 MPH
36H 22/1800Z 15.3N 102.0W 100 KT 115 MPH
48H 23/0600Z 15.9N 102.4W 115 KT 130 MPH
60H 23/1800Z 16.6N 103.0W 125 KT 145 MPH
72H 24/0600Z 17.5N 104.1W 125 KT 145 MPH
96H 25/0600Z 18.7N 106.6W 120 KT 140 MPH
120H 26/0600Z 19.8N 109.0W 115 KT 130 MPH
$$
Forecaster Cangialosi/Kelly
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 210900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 24W (DUJUAN) WARNING NR 024//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 33.7N 139.8E
INITIAL INTENSITY: 70 KTS
GEOGRAPHIC REFERENCE: 96 NM SOUTH OF YOKOSUKA, JAPAN
MOVEMENT PAST 6 HOURS: NORTHEASTWARD AT 16 KTS
SIGNIFICANT WAVE HEIGHT: 32 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TYPHOON (TY)
24W
(DUJUAN) UNDERGOING A PRONOUNCED RECONSOLIDATION PHASE, CHARACTERIZED
BY SPIRAL BANDS OF DEEP CONVECTION WRAPPING TIGHTLY INTO A LOW-LEVEL
CIRCULATION CENTER (LLCC) FULLY OBSCURED BY A ROBUST CENTRAL DENSE
OVERCAST (CDO). THIS BRIEF STRENGTHENING TIMEFRAME IS DRIVEN
PRIMARILY BY A VERY STRONG POLEWARD OUTFLOW CHANNEL, SUPPORTED BY
CONDUCIVE SEA SURFACE TEMPERATURES (SST) OF 27-28 C, AND INCREASING
BUT STILL LOW TO MODERATE (15-20 KTS) VERTICAL WIND SHEAR (VWS). THE
SYSTEM HAS BEEN ABLE TO TRANSIENTLY COCOON ITSELF FROM THE
SURROUNDING DRY-AIR ADVECTION ENTRAINING INTO THE INNER VORTEX CORE.
THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON A FUSION
OF RADAR IMAGERY AND A 210556Z F18 SSMIS 91 GHZ MICROWAVE PASS. THE
INITIAL INTENSITY OF 70 KTS IS ALSO ASSESSED WITH HIGH CONFIDENCE,
SUPPORTED BY OBSERVED CONVECTIVE CONSOLIDATION, INCREASED DVORAK
AGENCY ESTIMATES, AND THE AUTOMATED OBJECTIVE AIDS LISTED BELOW.
INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK AND A 210051Z
METOP-C ASCAT
CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) CENTERED TO THE
EAST
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T4.5 - 77 KTS
RJTD: T5.0 - 90 KTS
RCTP: T4.5 - 77 KTS
CIMSS SATCON: 63 KTS AT 210422Z
CIMSS ADT: 55 KTS AT 210530Z
CIMSS AIDT: 54 KTS AT 210530Z
CIMSS D-MINT: 71 KTS AT 210422Z
CIMSS D-PRINT: 82 KTS AT 210630Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE
VWS: 15-20 KTS
SST: 27-28 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: TY DUJUAN IS FORECAST TO ACCELERATE ALONG A
NORTHEASTWARD TRANSLATION VECTOR OVER THE NEXT 12 HOURS AND MAINTAIN
THIS TRACK THROUGHOUT THE PREDICTION TIMEFRAME, COMMITTED TO THE
NORTHWESTERN FLANK OF THE SUBTROPICAL RIDGE ANCHORED TO THE EAST. THE
CLOSEST POINT OF APPROACH (CPA) TO YOKOSUKA, JAPAN IS ESTIMATED AT 81
NM AND EXPECTED TO OCCUR WITHIN THE NEXT 6 HOURS. DURING THIS TIME,
MODEST DEEPENING TO A PEAK INTENSITY OF 75 KTS IS PROJECTED UNDER A
MARGINALLY CONDUCIVE THERMODYNAMIC AND SYNOPTIC ENVIRONMENT. THIS
TRANSIENT STRENGTHENING PHASE IS SUPPORTED BY TY 24W BRIEFLY
SHIELDING ITSELF FROM HOSTILE DRY-AIR ENTRAINMENT WHILST TAPPING INTO
VERY STRONG POLEWARD OUTFLOW. SUBSEQUENT TO CPA PASSAGE AT YOKOSUKA,
THE VORTEX IS FORECAST TO TRACK DIRECTLY ACROSS THE THERMALLY
CONDUCIVE TAIL END OF THE KUROSHIO CURRENT (28-29 C) SHORTLY AFTER
TAU 12. HOWEVER, THE ONSET OF EXTRATROPICAL TRANSITION (ETT) WILL
INITIATE AS THERMODYNAMIC CONDITIONS DEGRADE OVER RAPIDLY COOLING SEA
SURFACE TEMPERATURES, COUPLED WITH RELENTLESS DRY AIR ADVECTION AND
DESTRUCTIVE VERTICAL WIND SHEAR REACHING 40+ KTS BY TAU 36. UPON
INTERACTING WITH THE STRONG BAROCLINIC REGIME AND THE UPPER-LEVEL
MID-LATITUDE WESTERLIES, TY DUJUAN WILL COMPLETE ETT BY THE END OF
THE FORECAST TIMEFRAME.
MODEL DISCUSSION: HIGH CONFIDENCE ANCHORS THE OFFICIAL JTWC TRACK
FORECAST, POSITIONED CLOSE TO THE MULTI-MODEL DYNAMICAL CONSENSUS IN
LIGHT OF EXCELLENT NUMERICAL MODEL AGREEMENT. ALL MAJOR PREDICTION
TRACKERS RESOLVE AN EXTREMELY TIGHT (5 NM) CROSS-TRA…
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 (50°), 5.8 kt | Gust: 7.8 kt
Pressure: 29.88 | Air Temp: 85.1 °F
Water Temp: 86.9 °F | Dew Point: 76.1 °F
Swell: 1.0 ft | Wind Wave: 1.0 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.
