🚨 Suwannee; Union; Bradford; Gilchrist; Eastern Alachua; Western Alachua; Southeastern Columbia; Southwestern Columbia: Special Weather Statement issued August 5 at 1:33PM EDT by NWS Jacksonville FL 🚨 Lake Okeechobee: Special Marine Warning issued August 5 at 1:31PM EDT until August 5 at 2:30PM EDT by NWS Miami FL 🚨 Chesapeake Bay north of Pooles Island MD; Chesapeake Bay from Pooles Island to Sandy Point MD; Chesapeake Bay from Sandy Point to North Beach MD; Tidal Potomac from Key Bridge to Indian Head MD; Tidal Potomac from Indian Head to Cobb Island MD; Tidal Potomac from Cobb Island MD to Smith Point VA; Patapsco River including Baltimore Harbor; Chester River to Queenstown MD; Eastern Bay; Choptank River to Cambridge MD and the Little Choptank River; Patuxent River to Broomes Island MD: Marine Weather Statement issued August 5 at 1:30PM EDT by NWS Baltimore MD/Washington DC 🚨 Waters from Englewood to Tarpon Springs FL out 20 to 60 NM: Marine Weather Statement issued August 5 at 1:28PM EDT by NWS Tampa Bay Ruskin FL 🚨 Montgomery: None 🚨 Fayette; Bourbon: Special Weather Statement issued August 5 at 1:25PM EDT by NWS Louisville KY 🚨 Hartford; Tolland; Windham; Eastern Franklin; Northern Worcester; Central Middlesex County; Western Essex; Eastern Essex; Eastern Hampshire; Eastern Hampden; Southern Worcester; Western Norfolk; Southeast Middlesex; Suffolk; Eastern Norfolk; Northern Bristol; Western Plymouth; Eastern Plymouth; Southern Bristol; Southern Plymouth; Northwest Middlesex County; Northwest Providence; Southeast Providence; Western Kent; Eastern Kent; Bristol; Washington; Newport: Heat Advisory issued August 5 at 1:25PM EDT until August 7 at 8:00PM EDT by NWS Boston/Norton MA 🚨 Burlington, NJ; Mercer, NJ; Bucks, PA: Flash Flood Warning issued August 5 at 1:23PM EDT until August 5 at 5:30PM EDT by NWS Mount Holly NJ 🚨 Southern Litchfield; Eastern Ulster; Western Dutchess: Heat Advisory issued August 5 at 1:22PM EDT until August 7 at 8:00PM EDT by NWS Albany NY 🚨 Bannock, ID; Bingham, ID; Caribou, ID; Oneida, ID; Power, ID: Air Quality Alert issued August 5 at 11:18AM MDT by NWS Pocatello ID
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 051500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 12W (DOLPHIN) WARNING NR 039//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 25.9N 136.2E
INITIAL INTENSITY: 90 KTS
GEOGRAPHIC REFERENCE: 454 NM EAST OF KADENA AB
MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 09 KTS
SIGNIFICANT WAVE HEIGHT: 41 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A VERY
COMPACT INNER CORE OF MODERATE CONVECTION SURROUNDING A SMALL,
APPROXIMATELY 10NM WIDE EYE FEATURE, WHICH WAS SEVERELY ERODED ON
THE WESTERN FLANK. ANIMATED SHORTWAVE INFRARED AND PROXY VISIBLE
IMAGERY AND A 051114Z MHS 89GHZ MICROWAVE IMAGE DEPICT A STATIONARY
BANDING FEATURE (SBC) WRAPPING IN FROM THE SOUTH, UP THE EASTERN FLANK
AND INTO THE INNER CORE IN THE NORTHEASTERN QUADRANT, AS WELL AS A
MOAT OF RELATIVELY DRIER AIR EXTENDING AROUND NEARLY THE ENTIRE EXTENT
OF THE INNER CORE. LATER EIR IMAGERY DEPICTS THE EYEWALL REFORMING
ALONG THE WESTERN FLANK OF THE SYSTEM, THOUGH THE EYE CONTINUES TO
SHRINK IN SIZE. ANIMATED WATER VAPOR IMAGERY, AND DERIVED ATMOSPHERIC
MOTION VECTORS CONTINUE TO SHOW CYCLONIC OUTFLOW ALOFT, WHICH TURNS
ANTICYCLONIC ROUGHLY 100NM OUT FROM THE CENTER, AND NO DISTINCT
OUTFLOW CHANNELS. THE INITIAL POSITION IS ASSESSED WITH HIGH
CONFIDENCE BASED ON THE SMALL EYE IN THE EIR. THE INITIAL INTENSITY IS
ASSESSED WITH MEDIUM CONFIDENCE BASED ON A BLEND OF THE AVAILABLE
OBJECTIVE AND SUBJECTIVE INTENSITY ESTIMATES NOTED BELOW. LATE RECEIPT
OF A TRIFECTA OF SAR PASSES FROM APPROXIMATELY 0900Z (S1C, RCM3 AND
RSAT2) BRINGS THE INTENSITY ASSESSMENT INTO QUESTION, AS ALL THREE
SHOWED A VMAX SIGNIFICANTLY LOWER THAN THE CURRENT INTENSITY
ESTIMATES. THOUGH RECEIVED TOO LATE TO INFLUENCE THIS FORECAST, LATER
REANALYSIS MAY RESULT IN A LOWER INITIAL INTENSITY. ENVIRONMENTAL
CONDITIONS REMAIN GENERALLY FAVORABLE. SSTS REMAIN VERY WARM, THOUGH
OHC IS LOW AS THE WARM LAYER IS VERY THIN. OHC INCREASES TO THE WEST
REACHING A LOCAL MAXIMUM JUST EAST OF OKINAWA. UPPER-LEVEL OUTFLOW IS
MODERATE TO STRONG, BUT THE CYCLONIC NATURE OF THE UPPER-LEVEL FLOW
PRODUCES AN OVERALL NEGATIVE EFFECT ON TC INTENSITY. SHEAR REMAINS
LOW, WITH NO MAJOR CHANGES EXPECTED.
INITIAL WIND RADII BASIS: SCATTEROMETER DATA
CURRENT STEERING MECHANISM: SOUTHERN FLANK OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) CENTERED OVER THE SEA OF JAPAN (SOJ).
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T5.0 - 90 KTS
RJTD: T5.5 - 102 KTS
RCTP: T4.5 - 77 KTS
KNES: T4.5 - 77 KTS
CIMSS ADT: 95 KTS AT 051200Z
CIMSS AIDT: 94 KTS AT 051200Z
CIMSS D-PRINT: 88 KTS AT 051130Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 5-10 KTS
SST: 29-30 CELSIUS
OUTFLOW: STRONG RADIAL
OTHER FACTORS: SECONDARY EYEWALL FORMATION.
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: MEDIUM
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 12W HAS TAKEN A BIT OF A MORE
WEST-NORTHWESTWARD TRACK THAN EXPECTED OVER THE PAST 12 HOURS, SOME
OF WHICH CAN BE ATTRIBUTED TO TROCHOIDAL WOBBLE, BUT ALSO DUE TO A
SLIGHT DISPLACEMENT OF THE STR FURTHER NORTH THAN ANTICIPATED. OVER
THE PAST TWO HOURS, HOWEVER, THE TRACK APPEARS TO BE STABILIZING,
MOVING DUE WESTWARD ALONG THE 26N LATITUDE LINE. THE SYSTEM IS
EXPECTED TO CONTINUE TRACKING WEST-NORTHWESTWARD ALONG THE SOUTHERN
SIDE OF THE STR OVER THE SOJ THROUGH THE ENTIRE FORECAST PERIOD.
GLOBAL MODELS STILL SHOW A MAJOR SHORTWAVE TROUGH MOVING ACROSS
NORTHEASTERN CHINA AND INTO EASTERN RUSSIA BY TAU 48, AND THEY
STILL SHOW A WEAKNESS DEVELOPING IN THE DEEP-LAYER STEERING RIDGE
OVER THE KOREAN PENINSULA. HOWEVER,…
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 051500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 13W (KUJIRA) WARNING NR
004//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 17.8N 119.8E
INITIAL INTENSITY: 35 KTS
GEOGRAPHIC REFERENCE: 204 NM NORTH-NORTHWEST OF MANILA,
PHILIPPINES
MOVEMENT PAST 6 HOURS: EASTWARD AT 08 KTS
SIGNIFICANT WAVE HEIGHT: 12 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED SHORTWAVE INFRARED (SWIR) SATELLITE IMAGERY DEPICTS A
COMPACT LOW-LEVEL CIRCULATION CENTER (LLCC) LOCATED JUST NORTHWEST
OF VIGAN, PHILIPPINES. OVER THE PAST 2-3 HOURS, DEEP CONVECTION HAS
RE-DEVELOPED ALONG THE SOUTHWESTERN PERIPHERY OF THE VORTEX AND
EXPANDED NORTHWARD, ENVELOPING THE LLCC. OUTER CONVECTIVE BANDS ALONG
THE EASTERN FLANK OF TS 13W ARE RESOLVED ON THE PAGASA RADAR LOOP,
PROVIDING HIGHER CONFIDENCE IN THE CENTER POSITION (ASSESSED WITH
MEDIUM CONFIDENCE). THE INITIAL INTENSITY IS ASSESSED AT 35 KNOTS WITH
MEDIUM CONFIDENCE, CONSISTENT WITH RECENT SCATTEROMETRY AND CIMSS ADT
AND D-PRINT ESTIMATES. WHILE CIMSS ANALYSIS INDICATES 15 KNOTS OF
DEEP-LAYER VERTICAL WIND SHEAR (VWS), CIRA DERIVED MOTION VECTOR
(DMV) WINDS AND WATER VAPOR IMAGERY INDICATE A SIGNIFICANT WEAKENING
OF UPPER-LEVEL NORTHEASTERLY WINDS ALONG THE SYSTEM'S NORTHEASTERN
FLANK, RESULTING IN A LOWER SHEAR ENVIRONMENT OVER THE CORE. THIS
DIAGNOSIS IS SUBSTANTIATED BY RECENT CONVECTIVE RE-DEVELOPMENT AND
RAPID VERTICAL VORTEX ALIGNMENT OBSERVED IN THE SWIR ANIMATIONS.
OVERALL, THE ENVIRONMENT IS CHARACTERIZED AS MARGINAL; WHILE PROXIMITY
TO LAND IMPEDES CONSOLIDATION, HIGH SSTS (29-30C), LOW VWS, AND STRONG
EQUATORWARD OUTFLOW FAVOR DEVELOPMENT.
INITIAL WIND RADII BASIS: PERSISTENCE
CURRENT STEERING MECHANISM: WEAK STEERING ENVIRONMENT, DOMINATED BY
THE LOWER-LEVEL SOUTHWESTERLY MONSOONAL SURGE FLOW.
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.0 - 30 KTS
RJTD: T2.0 - 30 KTS
RCTP: T2.0 - 30 KTS
KNES: T2.0 - 30 KTS
CIMSS ADT: 35 KTS AT 051200Z
CIMSS AIDT: 31 KTS AT 051200Z
CIMSS D-PRINT: 33 KTS AT 051210Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINAL
VWS: 15-20 KTS
SST: 29-30 CELSIUS
OUTFLOW: STRONG EQUATORWARD
OTHER FACTORS: PROXIMITY TO LAND.
ANALYSIS CONFIDENCE:
INITIAL POSITION: MEDIUM
INITIAL INTENSITY: MEDIUM
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 13W HAS TURNED EASTWARD AND ACCELERATED
TOWARDS WESTERN LUZON SINCE THE 0600Z ANALYSIS. LOW-LEVEL
SOUTHWESTERLIES ASSOCIATED WITH A MONSOON SURGE ARE INTENSIFYING,
STEERING TS 13W EAST-SOUTHEASTWARD THROUGH TAU 24. LANDFALL ALONG THE
COAST BETWEEN VIGAN AND LAOAG IS EXPECTED WITHIN THE NEXT FEW HOURS,
FOLLOWED BY RAPID ACCELERATION ACROSS NORTHERN LUZON AND OFFSHORE
EMERGENCE INTO THE PHILIPPINE SEA BETWEEN TAU 12 AND TAU 18. THROUGH
THE REMAINDER OF THE FORECAST PERIOD, THE SYSTEM WILL CONTINUE ON AN
EAST-NORTHEASTWARD TRAJECTORY ALONG THE NORTHERN PERIPHERY OF THE
SURGING MONSOON SOUTHWESTERLIES. REGARDING INTENSITY, BRIEF
INTENSIFICATION UP TO 40 KNOTS IS POSSIBLE IMMEDIATELY PRIOR TO
LANDFALL; HOWEVER, TERRAIN INTERACTION OVER NORTHERN LUZON WILL
INDUCE STEADY WEAKENING. DUE TO THE RAPID TRANSLATION SPEED, TS 13W
WILL EMERGE OFFSHORE AS A 25-30 KNOT TROPICAL DEPRESSION BEFORE
DEGENERATING INTO AN OPEN TROUGH BY TAU 24, FEATURING AN ASYMMETRIC
WIND FIELD WITH 25-30 KNOT MONSOON SURGE WINDS CONFINED TO THE
SOUTHERN FLANK. AS THE SYSTEM OPENS INTO A TROUGH, IT WILL LOSE
TROPICAL CHARACTERISTICS WHILE MAINTAINING WINDS ABOVE WARNING
THRESHOLDS. BEYOND THE END OF THE FORECAST PERIOD, THE REMNANT
VORTICITY WILL TRACK NORTHEASTWARD AND BE ABSORBED INTO THE EXPANSIVE
CIRCULATION OF TY 12W PASSING…
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 (120°), 3.9 kt | Gust: 7.8 kt
Pressure: 30.08 steady | Air Temp:
Water Temp: 88.0 °F | Dew Point:
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.
