🚨 Davison, SD; Douglas, SD; Hanson, SD; Hutchinson, SD; Turner, SD: Severe Thunderstorm Warning issued September 8 at 12:29AM CDT until September 8 at 12:45AM CDT by NWS Sioux Falls SD 🚨 Montgomery: None 🚨 Cape Cod Bay; Nantucket Sound; Vineyard Sound; Buzzards Bay: Gale Watch issued September 8 at 1:22AM EDT until September 10 at 12:00PM EDT by NWS Boston/Norton MA 🚨 Dorchester; Wicomico; Somerset: The Coastal Flood Advisory has been cancelled. 🚨 Montague; Cooke; Grayson; Wise; Denton; Collin; Hunt; Delta; Hopkins; Tarrant; Dallas; Rockwall; Kaufman; Van Zandt; Rains; Johnson; Ellis; Henderson; Navarro: Heat Advisory issued September 8 at 12:01AM CDT until September 8 at 8:00PM CDT by NWS Fort Worth TX 🚨 Hill; Freestone; Anderson; Bell; McLennan; Falls; Limestone; Leon; Milam; Robertson: Heat Advisory issued September 8 at 12:01AM CDT until September 8 at 8:00PM CDT by NWS Fort Worth TX 🚨 Fannin; Lamar: Heat Advisory issued September 8 at 12:01AM CDT until September 8 at 8:00PM CDT by NWS Fort Worth TX 🚨 Coastal Glynn; Coastal Camden: Rip Current Statement issued September 8 at 12:52AM EDT until September 9 at 4:00AM EDT by NWS Jacksonville FL 🚨 Coastal Nassau; Coastal Duval; Northeast Coastal St. Johns; Southeast Coastal St. Johns: Rip Current Statement issued September 8 at 12:52AM EDT until September 9 at 4:00AM EDT by NWS Jacksonville FL 🚨 Northern Lynn Canal: Small Craft Advisory issued September 7 at 8:51PM AKDT until September 8 at 4:00PM AKDT by NWS Juneau AK
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 MIATCDEP3 ALL
TTAA00 KNHC DDHHMM
Tropical Storm Marie Discussion Number 28
NWS National Hurricane Center Miami FL EP132026
800 PM PDT Mon Sep 07 2026
Marie continues its gradual weakening trend, although the cyclone
still has a substantial low-level circulation. Deep convection is
minimal and confined to the southeastern quadrant of the system.
Based on a continued slow spin down from the earlier scatterometer
overpass, the winds are reduced slightly to 45 kt for this advisory,
although this may be generous. Another scatterometer overpass
should sample the system in a few hours.
The storm continues its slow west-northwestward trek with an initial
motion estimate of around 290/7 kt. There is not much change to the
track forecast. Marie is expected to turn northwestward soon and
move within the flow between a ridge extending westward from the
southwestern U.S. and a cutoff low to the west of the tropical
cyclone. The official forecast is similar to the previous NHC
track, and is close to the corrected model consensus.
Marie is over SSTs near 24 deg C and it should encounter even cooler
waters during the next day or so. Given the decreasing convection,
it now appears that the cyclone will become post-tropical in 24
hours, and this is reflected in the official forecast. Unless deep
convection redevelops in the system soon, however, Marie's
post-tropical transition could occur even earlier than indicated
here.
FORECAST POSITIONS AND MAX WINDS
INIT 08/0300Z 25.1N 125.9W 45 KT 50 MPH
12H 08/1200Z 25.8N 126.9W 40 KT 45 MPH
24H 09/0000Z 27.2N 127.9W 35 KT 40 MPH...POST-TROPICAL
36H 09/1200Z 29.1N 129.1W 30 KT 35 MPH...POST-TROP/REMNT LOW
48H 10/0000Z 31.3N 130.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
60H 10/1200Z 33.4N 132.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 11/0000Z...DISSIPATED
$$
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 080300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 22W (KROVANH)
WARNING NR 028//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 30.3N 132.6E
INITIAL INTENSITY: 30 KTS
GEOGRAPHIC REFERENCE: 224 NM SOUTHEAST OF SASEBO, JAPAN
MOVEMENT PAST 6 HOURS: NORTH-NORTHWESTWARD AT 12 KTS
SIGNIFICANT WAVE HEIGHT: 14 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TROPICAL
DEPRESSION (TD) 22W FEATURING A FULLY EXPOSED LOW-LEVEL CIRCULATION
CENTER (LLCC) AND FLARING CONVECTION IN THE NORTHWEST QUADRANT,
VENTING INTO A JET STREAK OVER THE EASTERN SEA OF JAPAN. ALTHOUGH
THE SYSTEM HAS TAKEN A NORTH-NORTHWESTWARD JOG OVER THE LAST SIX
HOURS, IT IS EMBEDDED IN DEEP-LAYER SOUTHERLY FLOW ON THE WESTERN
PERIPHERY OF A STRONG ANTICYCLONE SOUTHEAST OF HONSHU. THE
ANTICYCLONIC FLOW ASSOCIATED WITH THE UPPER-LEVEL RIDGE IS
ESPECIALLY STRONG, IMPARTING 20-25 KTS OF SOUTHERLY VERTICAL WIND
SHEAR (VWS) OVER THE SYSTEM. TD 22W IS MOVING OVER WATERS OF 28-29
DEGREES CELSIUS, BUT THE COMBINATION OF MODERATE TO HIGH VWS AND
SUBSTANTIAL DRY AIR INTRUSION INTO THE CIRCULATION RESULTS IN A
LARGELY UNFAVORABLE ENVIRONMENT FOR TROPICAL DEVELOPMENT. DESPITE
THESE FACTORS, TD 22W HAS NOT APPRECIABLY WEAKENED, AS EVIDENCED BY
A TIMELY 072359Z BULLS-EYE ASCAT-B PASS INDICATING WINDS OF UP TO
30 KTS IN THE SOUTHEAST QUADRANT, CONSISTENT WITH THE 071158Z
ASCAT-C DATA. THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE
BASED ON THE WELL-DEFINED LLCC IN THE MSI. THE INITIAL INTENSITY IS
HELD AT 30 KTS WITH HIGH CONFIDENCE BASED ON THE RECENT
SCATTEROMETER DATA.
INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND
RADII).
CURRENT STEERING MECHANISM: WESTERN FLANK OF THE SUBTROPICAL RIDGE
(STR) POSITIONED SOUTHEAST OF HONSHU
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T1.5 - 25 KTS
RJTD: T1.5 - 25 KTS
KNES: T1.5 - 25 KTS
CIMSS SATCON: 45 KTS AT 071940Z
CIMSS ADT: 41 KTS AT 072330Z
CIMSS AIDT: 40 KTS AT 072330Z
CIMSS D-MINT: 31 KTS AT 072012Z
CIMSS D-PRINT: 29 KTS AT 072330Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: UNFAVORABLE
VWS: 20-25 KTS
SST: 28-29 CELSIUS
OUTFLOW: MODERATE POLEWARD
OTHER FACTORS: 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 22W WILL CONTINUE POLEWARD ALONG THE
WESTERN FLANK OF THE STR SOUTHEAST OF HONSHU THROUGH TAU 12. BY TAU
24, THE SYSTEM WILL ROUND THE NORTHWESTERN PERIPHERY OF THE RIDGE
AND TURN NORTHEASTWARD AS IT INTERACTS WITH A STATIONARY FRONT NEAR
THE SOUTHERN COAST OF HONSHU. THIS MOTION WILL CONTINUE UNTIL
DISSIPATION BY TAU 36. WHILE TD 22W WILL TRACK OVER SUFFICIENTLY
WARM WATERS PRIOR TO LANDFALL, PERSISTENT VWS AND DRY AIR INTRUSION
WILL MAINTAIN AN UNFAVORABLE ENVIRONMENT FOR TROPICAL DEVELOPMENT.
THESE FACTORS WOULD NORMALLY LEAD TO WEAKENING. HOWEVER, AS TD 22W
CONTINUES TO GAIN LATITUDE, THE EXTENSIVE ANTICYCLONE SOUTHEAST OF
HONSHU WILL SHIFT WESTWARD, TIGHTENING THE SURFACE PRESSURE
GRADIENT BETWEEN THE SYSTEM AND THE RIDGE AND ENHANCING LOW-LEVEL
WINDS, PARTICULARLY OVER THE EASTERN PORTION OF THE CIRCULATION.
CONCURRENTLY, THE SOUTHEASTERN COASTLINE OF KYUSHU MAY ENHANCE THE
COAST-PARALLEL FLOW, SUPPORTING A LOCALIZED COASTAL JET OVER THE
WESTERN PORTION OF THE LLCC. THESE EFFECTS WILL SUPPORT A 30-KT
INTENSITY THROUGH TAU 12. AFTER LANDFALL, TERRAIN INTERACTION OVER
HONSHU WILL PROMOTE STEADY WEAKENING THROUGH DISSIPATION BY TAU 36.
THEREFORE, THE JTWC INTENSITY FORECAST MAINTAINS 30 KTS THROUGH TAU
12 AND THEN WEAKENS THE SYSTEM TO DISSIPA…
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: ESE (110°), 3.9 kt | Gust: 5.8 kt
Pressure: 29.98 steady | Air Temp: 86.4 °F
Water Temp: 88.0 °F | Dew Point: 79.3 °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.
