🚨 Montgomery: None 🚨 Tinian; Saipan: Tropical Storm Warning issued October 3 at 3:33AM ChST by NWS Tiyan GU 🚨 Coastal waters from Fernandina Beach to St. Augustine FL out 20 NM: Special Marine Warning issued October 2 at 1:24PM EDT until October 2 at 2:30PM EDT by NWS Jacksonville FL 🚨 Fillmore, NE; York, NE: Flood Warning issued October 2 at 12:24PM CDT until October 3 at 1:00PM CDT by NWS Hastings NE 🚨 Lake; Osceola; Clare; Newaygo; Mecosta: Frost Advisory issued October 2 at 1:23PM EDT until October 3 at 8:00AM EDT by NWS Grand Rapids MI 🚨 Hormigueros, PR; Mayaguez, PR: Flood Advisory issued October 2 at 1:21PM AST until October 2 at 3:30PM AST by NWS San Juan PR 🚨 Flagler Beach to Volusia-Brevard County Line 0-20 nm; Volusia-Brevard County Line to Sebastian Inlet 0-20 nm; Flagler Beach to Volusia-Brevard County Line 20-60 nm; Volusia-Brevard County Line to Sebastian Inlet 20-60 nm: Marine Weather Statement issued October 2 at 1:19PM EDT by NWS Melbourne FL 🚨 Icy Cape to Cape Suckling out to 15 NM: Small Craft Advisory issued October 2 at 9:19AM AKDT until October 3 at 5:00AM AKDT by NWS Juneau AK 🚨 Icy Cape to Cape Suckling from 15 to 80 NM: Small Craft Advisory issued October 2 at 9:19AM AKDT until October 3 at 5:00AM AKDT by NWS Juneau AK 🚨 Mobile Coastal: Coastal Flood Advisory issued October 2 at 12:17PM CDT until October 3 at 8:00AM CDT by NWS Mobile AL
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
Hurricane Rachel Discussion Number 22
NWS National Hurricane Center Miami FL EP182026
800 AM MST Fri Oct 02 2026
Rachel's inner core looks slightly less impressive on satellite
imagery than it did 6 to 12 hours ago. The eyewall is not very tight
and compact, with areas of dry air intrusion possibly affecting the
eyewall. The latest TAFB current intensity estimate is 5.5/102 kt,
but the final-T number is 4.5/77 kt. Objective intensity estimates
from UW-CIMSS have been ranging from 80-95 kt. The initial
intensity is lowered to 95 kt, which is 5 kt lower than the previous
NHC advisory.
The cyclone is still moving slowly westward at 265/5 kt and will be
making its closest approach to Socorro Island today. This motion is
expected to continue with a gradual increase in forward speed over
the weekend and into early next week as a mid-level ridge builds to
the north. A gradual bend toward the west-northwest is forecast by
Monday as the ridge begins to weaken. The track guidance remains in
fair agreement on this scenario, although some differences remain in
the timing of the increase in forward speed by early next week. The
latest NHC track forecast is similar to the previous prediction and
lies near the HCCA aid. The NHC forecast is a bit to the south of
the latest Google DeepMind Ensemble Mean.
Moderate east-northeasterly vertical wind shear might be helping
some dry mid-level air to entrain into Rachel's core, which seems to
be causing the eyewall to become a bit more spread out and diffuse
compared to 12 hours ago. These conditions are not forecast to
abate during the next 24 hours. All the guidance shows weakening
during the next 24 hours, and so does the official forecast, which
is about 15 kt lower than the previous NHC prediction at hour 12 and
24. This forecast remains near the high end of the guidance.
Beyond hour 24 the shear should relax somewhat, which should allow
Rachel to maintain hurricane intensity for the next 4 days or so.
The latest forecast flatlines the intensity at 70 kt from hour 36 to
day 4, which is also near the high end of the guidance, but lower
than the previous NHC forecast. It should be noted that the HAFS
models, HWRF and HMON show Rachel weakening to a tropical storm
within the next 24 hours, and then staying at tropical storm
strength through the period. After day 4, Rachel will move across
the 26C sea-surface temperature isotherm toward cooler water while
also reaching a progressively drier mid-level airmass. These
conditions should cause Rachel to weaken to a tropical storm by the
end of the forecast period.
FORECAST POSITIONS AND MAX WINDS
INIT 02/1500Z 19.3N 110.8W 95 KT 110 MPH
12H 03/0000Z 19.3N 111.4W 85 KT 100 MPH
24H 03/1200Z 19.6N 112.1W 75 KT 85 MPH
36H 04/0000Z 19.8N 112.9W 70 KT 80 MPH
48H 04/1200Z 20.0N 113.9W 70 KT 80 MPH
60H 05/0000Z 20.2N 115.0W 70 KT 80 MPH
72H 05/1200Z 20.3N 116.3W 70 KT 80 MPH
96H 06/1200Z 20.8N 119.5W 70 KT 80 MPH
120H 07/1200Z 21.7N 122.8W 60 KT 70 MPH
$$
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.
WDPN32 PGTW 021500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 26W (CHOI-WAN) WARNING NR 011//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 17.7N 144.6E
INITIAL INTENSITY: 70 KTS
GEOGRAPHIC REFERENCE: 165 NM NORTH-NORTHWEST OF SAIPAN
MOVEMENT PAST 6 HOURS: NORTHWARD AT 08 KTS
SIGNIFICANT WAVE HEIGHT: 28 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS TYPHOON
(TY) 26W AS A QUICKLY DEVELOPING SYSTEM WITH ROBUST DEEP CONVECTION
AND AN IMPROVING POLEWARD OUTFLOW CHANNEL. THE UPPER-LEVEL
CONVECTION IS STRUGGLING TO MAINTAIN ORGANIZATION, THOUGH IT IS
STILL FIGHTING TO WRAP UPSHEAR. THE LOWER-LEVEL CLOUD BANDING IS
STILL PARTIALLY EXPOSED ALONG THE NORTHWESTERN EDGE OF THE
CIRCULATION. THE 020832Z SAR PASS REVEALED A WIDE SWATH OF
TYPHOON-FORCE WINDS AND A SYMMETRICAL INNER CORE. ENVIRONMENTAL
ANALYSIS REVEALS A HIGHLY FAVORABLE ENVIRONMENT CHARACTERIZED BY LOW
(5-10 KTS) VERTICAL WIND SHEAR (VWS), WARM (29-30 C) SEA SURFACE
TEMPERATURES (SST), HIGH (100-120 KJ PER CM SQUARED) OCEAN HEAT
CONTENT (OHC), AND STRONG DIVERGENCE ALOFT. THE INITIAL POSITION IS
PLACED WITH MEDIUM CONFIDENCE BASED ON LOWER-LEVEL CLOUD BANDING
AND EXTRAPOLATION FROM THE EARLIER 020832Z RCM-3 SAR DATA. THE
INITIAL INTENSITY OF 70 KTS IS ASSESSED WITH HIGH CONFIDENCE ALSO
BASED ON THE SAR DATA. THE CIMSS INTENSITY ESTIMATES ARE ASSESSED
TO BE UNDERESTIMATING THE ACTUAL INTENSITY OF THE STORM.
INITIAL WIND RADII BASIS: 020832Z RCM-3 SAR DATA
CURRENT STEERING MECHANISM: THE SOUTHWESTERN PERIPHERY OF A
SUBTROPICAL RIDGE (STR) CENTERED TO THE NORTHWEST
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T3.5 - 55 KTS
RJTD: T3.5 - 55 KTS
RCTP: T3.5 - 55 KTS
CIMSS ADT: 55 KTS AT 021240Z
CIMSS AIDT: 46 KTS AT 021240Z
CIMSS D-MINT: 66 KTS AT 020800Z
CIMSS D-PRINT: 63 KTS AT 021130Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY FAVORABLE
VWS: 5-10 KTS
SST: 29-30 CELSIUS
OUTFLOW: STRONG EQUATORWARD
ANALYSIS CONFIDENCE:
INITIAL POSITION: MEDIUM
INITIAL INTENSITY: HIGH
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 26W (CHOI-WAN) IS CURRENTLY TRACKING
POLEWARD AS THE STR TO ITS NORTHEAST IS ERODED BY A PASSING
SHORTWAVE TROUGH TO THE NORTH. THE TROUGH WILL CONTINUE TO ERODE
THE WESTERN FLANK OF THE STR THROUGH TAU 36-48, INDUCING A
NORTHEASTWARD TRACK FOR CHOI-WAN. BY TAU 48, THE TROUGH IS EXPECTED
TO HAVE PASSED, AND THE STR IS EXPECTED TO RE-ORIENT AND BUILD
WESTWARD. THIS IS EXPECTED TO CAUSE 26W TO CURVE NORTHWESTWARD
BETWEEN TAU 48-72. JUST AFTER TAU 72, 26W IS ANTICIPATED TO ROUND
THE RIDGE AXIS AND SKIRT THE EDGE OF THE UPPER-LEVEL WESTERLIES.
26W IS FORECAST TO MAINTAIN A NORTHEASTWARD TRACK THROUGH THE END
OF THE FORECAST. THE ENVIRONMENT WILL DETERIORATE DRASTICALLY AS
26W TRACKS FURTHER POLEWARD. CHOI-WAN IS EXPECTED TO CROSS THE 26C
ISOTHERM AROUND TAU 96 AND ENCOUNTER HIGH (30+ KTS) VWS DUE TO THE
PROXIMITY TO THE WESTERLIES, WHICH WILL FORCE HIGH AMOUNTS OF DRY
AIR INTO THE CORE AND INDUCE THERMAL ADVECTION. IN RESPONSE TO THE
HOSTILE ENVIRONMENT, 26W IS FORECAST TO BEGIN EXTRATROPICAL
TRANSITION AT TAU 96 AND COMPLETE TRANSITION NO LATER THAN TAU 120.
REGARDING INTENSITY, 26W IS FORECAST TO UNDERGO A PERIOD OF RAPID
INTENSIFICATION BEGINNING IMMINENTLY AND LASTING THROUGH TAU 24.
WITHIN THE NEXT 12 HOURS, THE ENVIRONMENT WILL BECOME INCREASINGLY
FAVORABLE, WITH REDUCED VWS OF 10-15 KTS, AN ENHANCED POLEWARD
OUTFLOW CHANNEL PROVIDED BY THE RETREATING STR, AND HIGHER (150+ KJ
PER CM SQUARED) OHC. BY TAU 36, 26W IS FORECAST TO ENTER INTO A
REGION OF LOWER OHC (50-75 KJ PER CM SQUARED), WHICH IS EXPECTED TO
INDUCE A WEAK…
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: SSE (160°), 15.5 kt | Gust: 19.4 kt
Pressure: 29.89 | Air Temp: 78.8 °F
Water Temp: 86.2 °F | Dew Point: 77.7 °F
Swell: 0.0 ft | Wind Wave: 5.2 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.
