🚨 Presque Isle Light to Sturgeon Pt MI Including Thunder Bay National Marine Sanctuary; Sturgeon Pt to Alabaster MI: Small Craft Advisory issued November 7 at 6:26AM EST until November 7 at 10:00AM EST by NWS Gaylord MI 🚨 Greene; Macoupin; Montgomery; Bond; Fayette; Clinton; Marion; Washington; Randolph; Adams; Brown; Pike; Calhoun; Jersey; Madison; St. Clair; Monroe; Knox; Lewis; Shelby; Marion; Monroe; Ralls; Pike; Boone; Audrain; Moniteau; Cole; Osage; Callaway; Montgomery; Lincoln; Gasconade; Warren; St. Charles; Franklin; St. Louis; St. Louis City; Jefferson; Crawford; Washington; St. Francois; Ste. Genevieve; Iron; Madison; Reynolds: Freeze Warning issued November 7 at 5:25AM CST until November 7 at 8:00AM CST by NWS St Louis MO 🚨 Montgomery: None 🚨 Calhoun; Clarendon; Northwestern Orangeburg; Central Orangeburg; Southeastern Orangeburg: Dense Fog Advisory issued November 7 at 6:11AM EST until November 7 at 8:00AM EST by NWS Columbia SC 🚨 James River from JRB to HRBT, Including the Elizabeth River: Small Craft Advisory issued November 7 at 6:01AM EST until November 7 at 10:00AM EST by NWS Wakefield VA 🚨 Coastal waters from Fenwick Island DE to Chincoteague VA out 20 NM; Coastal waters from Chincoteague to Parramore Island VA out 20 NM; Coastal waters from Parramore Island to Cape Charles Light VA out 20 NM; Coastal Waters from Cape Charles Light to Virginia-North Carolina border out 20 NM; Coastal waters from NC VA border to Currituck Beach Light NC out 20 NM: Small Craft Advisory issued November 7 at 6:01AM EST until November 8 at 10:00AM EST by NWS Wakefield VA 🚨 Chesapeake Bay from Smith Point to Windmill Point VA; Chesapeake Bay from Windmill Point to New Point Comfort VA: Small Craft Advisory issued November 7 at 6:01AM EST until November 8 at 10:00AM EST by NWS Wakefield VA 🚨 Chesapeake Bay from New Point Comfort to Little Creek VA; Chesapeake Bay from Little Creek VA to Cape Henry VA including the Chesapeake Bay Bridge Tunnel: Small Craft Advisory issued November 7 at 6:01AM EST until November 7 at 1:00PM EST by NWS Wakefield VA 🚨 Currituck Sound: Small Craft Advisory issued November 7 at 6:01AM EST until November 7 at 1:00PM EST by NWS Wakefield VA 🚨 San Diego County Coastal Areas; Orange County Coastal: Coastal Flood Advisory issued November 7 at 2:59AM PST until November 10 at 12:00PM PST by NWS San Diego CA
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.
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 070900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 31W (CEMPAKA) WARNING NR
005//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 20.0N 142.8E
INITIAL INTENSITY: 45 KTS
GEOGRAPHIC REFERENCE: 300 NM SOUTH-SOUTHEAST OF IWO TO
MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 16 KTS
SIGNIFICANT WAVE HEIGHT: 18 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TROPICAL
STORM 31W (CEMPAKA) WITH A FULLY OBSCURED LOW-LEVEL CIRCULATION
CENTER (LLCC) THAT HAS QUICKLY CONSOLIDATED OVER THE PAST 6 HOURS.
A 070627Z SSMIS 91 GHZ MICROWAVE IMAGE REVEALED A DEVELOPING
MICROWAVE EYE FEATURE WITH THE STRONGEST CONVECTION LOCATED WITHIN
THE SOUTHERN SEMICIRCLE. THE PRESENCE OF A MICROWAVE EYE JUST AFTER
THE LLCC BECAME OBSCURED SUPPORTS THE NOTION THAT 31W IS CURRENTLY
UNDERGOING RAPID INTENSIFICATION (RI). THE INITIAL POSITION IS
PLACED WITH HIGH CONFIDENCE BASED ON THE SSMIS MICROWAVE IMAGE IN
CONJUNCTION WITH THE ANIMATED MSI. THE INITIAL INTENSITY OF 45 KTS
IS ASSESSED WITH LOW CONFIDENCE DUE TO THE RAPID DEVELOPMENT OF THE
CORE OF THE SYSTEM LIKELY OUTPACING THE DVORAK-BASED ESTIMATES.
ENVIRONMENTAL ANALYSIS INDICATES THAT 31W IS IN A HIGHLY FAVORABLE
ENVIRONMENT FOR FURTHER DEVELOPMENT CHARACTERIZED BY STRONG
WESTWARD OUTFLOW ALOFT, LOW (10-15 KTS) VERTICAL WIND SHEAR, AND
WARM (28-29 C) SEA SURFACE TEMPERATURES.
INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK
CURRENT STEERING MECHANISM: THE SOUTHWESTERN FLANK OF A SUBTROPICAL
RIDGE (STR) POSITIONED TO THE NORTHEAST
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.5 - 35 KTS
RJTD: T2.0 - 30 KTS
RCTP: T2.5 - 35 KTS
CIMSS ADT: 34 KTS AT 070600Z
CIMSS AIDT: 38 KTS AT 070600Z
CIMSS D-MINT: 50 KTS AT 070327Z
CIMSS D-PRINT: 53 KTS AT 070600Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY FAVORABLE
VWS: 10-15 KTS
SST: 29-30 CELSIUS
OUTFLOW: STRONG WESTWARD
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: LOW
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 31W IS FORECAST TO CONTINUE TRACKING
NORTHWESTWARD, ALONG THE SOUTHWESTERN PERIPHERY OF THE STR, THROUGH
TAU 36. AFTERWARD, AN INCOMING LONGWAVE TROUGH IS EXPECTED TO BREAK
DOWN THE WESTERN PORTION OF THE RIDGE, CAUSING 31W TO BEGIN TURNING
NORTHWARD THROUGH TAU 48 BEFORE GETTING PICKED UP BY THE TROUGH AND
ACCELERATING EAST-NORTHEASTWARD. THERE IS SOME UNCERTAINTY
REVOLVING AROUND THE SPEED OF ADVANCE AFTER TAU 60. SOME MODELS
SHOW THE TROUGH ZOOMING BY AND REORIENTING THE STEERING RIDGE
EASTWARD IN A WAY THAT PREVENTS 31W FROM RECURVING. ADDITIONALLY, A
SEPARATE RIDGE CENTERED NEAR SOUTHERN CHINA COULD FURTHER INHIBIT
POLEWARD MOVEMENT DEPENDING ON HOW FAR EASTWARD IT BUILDS. THE
OTHER SCENARIO IS A BIT MORE STRAIGHTFORWARD, AND IS CURRENTLY THE
ONE REFLECTED BY THE JTWC FORECAST. THIS INVOLVES 31W SIMPLY
GAINING ENOUGH LATITUDE FOR IT TO ROUND THE RIDGE AXIS AND
EVENTUALLY BECOME ABSORBED BY THE FRONTAL BOUNDARY ASSOCIATED WITH
THE MID-LATITUDE TROUGH. IN TERMS OF INTENSITY, 31W IS FORECAST TO
RAPIDLY INTENSIFY THROUGH TAU 48 TO A PEAK OF AROUND 100 KTS AS THE
ENVIRONMENT REMAINS HIGHLY FAVORABLE. AFTER TAU 48, SHEAR AND DRY
AIR WILL BEGIN TO INCREASE, CAUSING THE SYSTEM TO BEGIN WEAKENING.
AROUND TAU 72, THE ENVIRONMENT WILL BECOME MUCH MORE HOSTILE, WITH
STRONG (OVER 30 KTS) WESTERLY SHEAR AND SIGNIFICANT DRY AIR
INTRUSION INTO THE CORE. 31W WILL THEN BEGIN EXTRATROPICAL
TRANSITION NEAR TAU 96 WITH COMPLETION OCCURRING NO LATER THAN TAU
120, AS THE VORTEX BECOMES STRETCHED AND ABSORBED INTO THE FRONTAL
BOUNDARY.
MODEL DISCUSSION: MODEL TRACK GUIDANCE IS IN GOOD AGREEMENT THROUGH
…
94S
(SH942027)
Type: TDMax Wind: 30 ktMin Pressure: 1008 hPaPosition: -13.6, 54.3Basin: South Indian
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.
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°), 13.6 kt | Gust: 17.5 kt
Pressure: 29.95 | Air Temp: 77.5 °F
Water Temp: | Dew Point: 70.2 °F
Swell: 0.3 ft | Wind Wave: 2.0 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.