ZCZC MIATCDAT4 ALL TTAA00 KNHC DDHHMM Hurricane Isaias Discussion Number 9 NWS National Hurricane Center Miami FL AL092026 400 PM CDT Thu Oct 08 2026 The eye of Isaias has become apparent on visible and infrared satellite imagery. Interestingly, this is the first eye noted on satellite pictures in the Atlantic basin during the 2026 Hurricane Season. The cloud tops have mostly warmed in the system, but the latest subjective Dvorak classification value from TAFB has increased to T4.5 or 77 kt. NOAA Hurricane Hunter aircraft observations do not indicate a drop in central pressure so far and the peak 700-mb flight-level winds have not increased. However, Tail Doppler Radar wind velocities from the aircraft measured just above the surface support increasing the intensity to 85 kt for this advisory. Satellite and aircraft center fixes indicate that the hurricane appears to have made its expected turn toward the northeast and the initial motion is now 050/10 kt. Isaias is expected to turn northward tomorrow and move between a mid-level ridge extending westward from the Bahamas to the Florida peninsula and a trough near the northwest Gulf Coast. On the forecast track, the center will move inland along the northern Gulf coast within the next 36 hours, and then pass over portions of the southeastern U.S. during the next few days. The official forecast is nudged slightly eastward and follows the latest corrected consensus model guidance. The intensity forecast remains somewhat problematic. The hurricane will be passing over Gulf waters of high oceanic heat content during the next day or so. In fact, the projected track of Isais shows it passing near a warm eddy overnight. However, the vertical wind shear, which is already significant, is expected to increase substantially during the next 36 hours. The current thinking is that the shear will not offset the conducive oceanic conditions until 12-24 hours, so further strengthening is anticipated overnight. The official intensity forecast is at the high end of the model guidance, but in consideration of the expected stronger wind shear in 24-36 hours, some decrease in intensity is indicated as Isaias approaches the coast. Regardless, Isaias is expected to remain a dangerous hurricane through landfall, and strong gusty winds are expected well inland after the center crosses the coast. Key Messages: 1. A life-threatening storm surge is expected from the Mouth of the Mississippi River to Suwannee, Florida. Residents in the warning area should follow advice given by local officials and evacuate immediately if told to do so. 2. Damaging hurricane force-winds are expected over portions of the Florida Panhandle, southern Alabama, and southern Mississippi where a Hurricane Warning is in effect. Residents in these areas should prepare for the possibility of long-duration power outages. 3. Damaging wind gusts are possible over much of central and northern Alabama, extreme eastern Mississippi, and portions of western and northern Georgia, especially in areas of higher terrain. Additional Tropical Storm and High Wind Watches and Warnings may be required for portions of that area later tonight. Residents should secure loose outdoor items, avoid driving high-profile vehicles, and prepare for power outages. 4. Isaias will bring areas of heavy rainfall to the central U.S. Gulf coast and much of the Southeast Friday into the weekend. Considerable flash and urban flooding, along with significant river flooding, will be possible. FORECAST POSITIONS AND MAX WINDS INIT 08/2100Z 24.4N 89.3W 85 KT 100 MPH 12H 09/0600Z 25.7N 88.4W 95 KT 110 MPH 24H 09/1800Z 28.2N 87.4W 85 KT 100 MPH 36H 10/0600Z 31.0N 87.2W 65 KT 75 MPH...INLAND 48H 10/1800Z 33.2N 87.8W 30 KT 35 MPH...INLAND 60H 11/0600Z 35.0N 87.8W 25 KT 30 MPH...POST-TROP/INLAND 72H 11/1800Z 37.0N 85.0W 20 KT 25 MPH...POST-TROP/INLAND 96H 12/1800Z...DISSIP…

ZCZC MIATCDEP3 ALL TTAA00 KNHC DDHHMM Tropical Storm Rachel Discussion Number 47 NWS National Hurricane Center Miami FL EP182026 200 PM PDT Thu Oct 08 2026 The convection for Rachel has continue to slowly degrade as dry air continues to hinder the cyclone. The cloud tops have continued to warm and now the coldest cloud tops are around -45 C. While the most recent TAFB subjective Dvorak intensity estimate is still 4.0/65 kt, the objective estimates from UW-CIMSS are in the range of 32-60 kt. Therefore, the initial intensity has been lowered to 55 kt for this advisory. The initial motion was estimated around 300/3 kt. The storm is being steered by high pressure located over the southwestern United States. In about 24 hours, a mid- to upper-level trough currently sweeping across the Pacific is expected to turn Rachel to the northeast and increase its forward speed. The track guidance has generally shifted towards the southeast with this advisory, therefore the current NHC forecast track has also shifted in that direction, favoring the HCCA and GDMI forecast aids. Rachel is expected to continue to weaken during the next 12 to 24 hours due to cooling sea-surface temperatures and dry mid-level air. The wind shear is expected to continue increase as the trough moves closer to the storm, which may cause additional weakening, however Rachel is expected to be at tropical storm strength when it nears Baja California. The current NHC intensity forecast is similar to the previous one, with some adjustments made based on the HCCA and GDMI forecast aids. Rachel could lose tropical cyclone status as deep convection wanes, however simulated satellite imagery from the global models suggest convection will return as it moves northwestward over warmer waters and is influenced by the approaching trough. Regardless of the status of Rachel on its approach to Baja California, heavy rainfall and tropical-storm-force winds are expected over portions of northwestern Mexico and the southwest United States. Key Messages: 1. Rachel is expected to approach the coast of northern Baja California, Mexico, and the northern Gulf of California at tropical storm strength over the weekend, and a Tropical Storm Watch could be required for a portion of this area by tonight. 2. Strong gusty winds associated with the remnants of Rachel are expected to spread over interior portions of the Southwest United States, especially in areas of higher terrain, from this weekend into early next week. 3. Rachel and the moisture associated with the system will spread over portions of the Southwest United States and northern Baja California peninsula through this weekend. This will lead to increasing coverage of rainfall and potential for flash and urban flooding. 4. Swells partly generated by Rachel will continue to build along the coast of Southern California and northern Baja California. These swells are likely to cause life-threatening surf and rip current conditions, as well as minor to moderate coastal flooding, through early next week. Please consult products from your local weather office. FORECAST POSITIONS AND MAX WINDS INIT 08/2100Z 22.4N 124.6W 55 KT 65 MPH 12H 09/0600Z 22.6N 125.1W 50 KT 60 MPH 24H 09/1800Z 23.0N 124.5W 45 KT 50 MPH 36H 10/0600Z 24.0N 122.6W 45 KT 50 MPH 48H 10/1800Z 26.2N 119.7W 45 KT 50 MPH 60H 11/0600Z 30.2N 116.3W 45 KT 50 MPH 72H 11/1800Z 33.3N 113.8W 40 KT 45 MPH...POST-TROP/INLAND 96H 12/1800Z...DISSIPATED $$ Forecaster Katz/Brown NNNN

ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM Tropical Storm Simon Discussion Number 6 NWS National Hurricane Center Miami FL EP202026 300 PM CST Thu Oct 08 2026 Simon is almost a hurricane. The storm continues to have a very compact inner core with some signs of an eye becoming apparent in satellite images. There are also numerous spiral bands beyond the inner core region, with the outermost band in the far northeast quadrant still affecting portions of southwestern Mexico. The latest satellite intensity estimates have increased a little from earlier and now range from about 50 to 65 kt. Based on that data, the initial intensity is nudged up to 60 kt. A 17Z ASCAT-C pass was used to adjust the initial wind radii. The tropical storm is moving slowly westward at about 5 kt, steered by a weak mid-level ridge to its north. A turn to the northwest is expected tonight or early Friday, followed by a northward motion later that day when the ridge weakens and shifts eastward, in response to an approaching mid- to upper-level trough. Although the models generally agree on the large-scale steering pattern evolution, there are very important differences in where and when the system makes that turn. There has been a notable shift to the east this cycle, and given the westward bias often seen in the models for this region, the NHC track forecast has been again nudged eastward. It should be noted that the best-performing models of the year so far are east of the official forecast, and additional adjustments might be needed if this trend continues. This forecast brings the core of the system inland over southwestern and west-central Mexico Saturday afternoon or Saturday night. Simon is in near ideal environmental conditions of low wind shear, high moisture, and over very warm waters. The SHIPS model shows more than a 70 percent chance that the system will rapidly intensify over the next 24 hours. In fact, the storm's compact inner core structure makes it even more likely that it will capitalize on the favorable conditions. Therefore, the NHC intensity forecast continues to call for rapid strengthening into a very dangerous category 4 hurricane before Simon reaches the coast of west-central Mexico. This forecast lies near the high end of the guidance, in best agreement with the HCCA model. Based on the new forecast, the government of Mexico has issued a Hurricane Warning for a portion of the coast of southwestern and west-central Mexico. Key Messages: 1. Simon is expected to strengthen to a hurricane by tonight and approach the west-central coast of Mexico as a major hurricane on Saturday. 2. Life-threatening wind and storm surge impacts are expected along a portion of the west-central coast of Mexico, and a Hurricane Warning is now in effect from Punta San Telmo to Playa Perula. Preparations to protect life and property should be completed by late Friday. 3. Heavy rainfall associated with Simon will impact portions of southwestern Mexico through this weekend. This rainfall may produce life-threatening flooding and mudslides, especially in areas of steep terrain. 4. Swells will affect portions of the southwestern and west-central coast of Mexico through the weekend. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. FORECAST POSITIONS AND MAX WINDS INIT 08/2100Z 15.7N 103.9W 60 KT 70 MPH 12H 09/0600Z 16.1N 104.4W 75 KT 85 MPH 24H 09/1800Z 16.8N 104.9W 95 KT 110 MPH 36H 10/0600Z 17.7N 105.0W 115 KT 130 MPH 48H 10/1800Z 18.8N 104.9W 115 KT 130 MPH 60H 11/0600Z 19.9N 104.9W 65 KT 75 MPH...INLAND 72H 11/1800Z 21.1N 104.8W 35 KT 40 MPH...INLAND 96H 12/1800Z 23.2N 105.0W 25 KT 30 MPH...POST-TROP/INLAND 120H 13/1800Z...DISSIPATED $$ Forecaster Cangialosi NNNN

WDPN31 PGTW 082100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 15E (NOLO) WARNING NR 073// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 27.8N 151.1E INITIAL INTENSITY: 50 KTS GEOGRAPHIC REFERENCE: 745 NM SOUTHEAST OF TOKYO, JAPAN MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 15 KTS SIGNIFICANT WAVE HEIGHT: 27 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: TS 15E HAS STRUGGLED TO MAINTAIN INTENSITY OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A NEAR DISSIPATION OF ALL DEEP CONVECTION, BUT A STILL TIGHTLY WRAPPED MID-LEVEL CIRCULATION. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE NEAR THE MID-POINT OF RECENT FIXES FROM PGTW, RJTD, AND RCTP AND IS CONSISTENT WITH EXTRAPOLATION FROM THE PREVIOUS BEST TRACK POSITION. THE INITIAL INTENSITY OF 50 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE HIGH END OF AVAILABLE SUBJECTIVE DVORAK AND AUTOMATED INTENSITY ESTIMATES TO ACCOUNT FOR A POTENTIAL LOW BIAS IN THOSE TECHNIQUES DUE TO THE RECENT, AND LIKELY TEMPORARY, DISSIPATION OF DEEP CONVECTION OVER THE CIRCULATION. INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK AND PERSISTENCE CURRENT STEERING MECHANISM: DEEP-LAYER SUBTROPICAL RIDGE (STR) TO THE NORTHEAST AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T3.0 - 45 KTS RJTD: T3.5 - 55 KTS RCTP: T3.0 - 45 KTS CIMSS ADT: 37 KTS AT 081750Z CIMSS AIDT: 41 KTS AT 081810Z CIMSS D-MINT: 39 KTS AT 081542Z CIMSS D-PRINT: 49 KTS AT 081810Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE VWS: 10-15 KTS SST: 28-29 CELSIUS OUTFLOW: MODERATE POLEWARD AND EQUATORWARD ANALYSIS CONFIDENCE: INITIAL POSITION: MEDIUM INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: MEDIUM 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TS 15E WILL TURN POLEWARD AND EASTWARD AROUND THE WESTERN PERIPHERY OF THE CURRENT STEERING RIDGE DURING THE 72 HOUR FORECAST PERIOD. THE SYSTEM WILL INTERACT WITH A SHALLOW SHORTWAVE TROUGH APPROACHING FROM THE WEST AND COMPLETE EXTRATROPICAL TRANSITION AFTER TAU 48. DESPITE NOTED TRENDS IN SATELLITE IMAGERY, TS 15E IS EXPECTED TO INTENSIFY SLIGHTLY OVER THE NEXT 24 HOURS AS IT PASSES OVER SUFFICIENTLY WARM WATER, VERTICAL WIND SHEAR REMAINS LOW TO MODERATE, AND IS IMPACTED BY A FAVORABLE OUTFLOW PATTERN SUPPORTING RENEWED CONVECTIVE ACTIVITY. HOWEVER, AFTER TAU 24 THE SYSTEM WILL ENCOUNTER INCREASING VERTICAL WIND SHEAR AND ENTRAINMENT OF DRIER AIR FROM THE WEST AS IT ROUNDS THE STEERING RIDGE AXIS, DRIVING A STEADY WEAKENING TREND. FAVORABLE BAROCLINIC SUPPORT SHOULD ALLOW THE SYSTEM TO MAINTAIN TROPICAL STORM LEVEL INTENSITY AS IT COMPLETES EXTRATROPICAL TRANSITION. MODEL DISCUSSION: NUMERICAL MODEL TRACK AND INTENSITY FORECAST GUIDANCE ARE BOTH IN GOOD AGREEMENT REGARDING THE OVERALL SCENARIO, INCLUDING A TIGHT TURN AROUND THE STEERING RIDGE AND SLIGHT NEAR-TERM INTENSIFICATION FOLLOWED BY GRADUAL WEAKENING AFTER TAU 24. PHYSICAL-BASED MODELS BROADLY DEPICT A WIDER AND SLOWER TURN THAN THE AI-BASED MODELS, RESULTING IN SIGNIFICANT CROSS-TRACK AND ALONG-TRACK SPREAD BY TAU 72. THERE IS NO CLEAR FACTOR FAVORING EITHER SOLUTION SET, AND OVERALL SPREAD AMONG ALL OF THE AVAILABLE GUIDANCE IS SPREAD EVENLY BETWEEN THE WESTERN AND EASTERN EDGES OF THE ENVELOPE. THE CURRENT FORECAST LIES ALONG A PLAUSIBLE TRACK IN THE MID-POINT OF ALL GUIDANCE, JUST SLIGHTLY TO THE WEST OF THE PREVIOUS JTWC TRACK FORECAST AS THE SYSTEM MAKES THE TURN. THE INTENSITY FORECAST IS CONSISTENT WITH CONSENSUS GUIDANCE AND THE PREVIOUS FORECAST, WITH UNCERTAINTY PRIMARILY CONFINED TO THE NEXT 24 HOURS GIVEN FAVORABLE ENVIRONMENTAL CONDITIONS BUT A POOR SATELLITE PRESENTATION. FORECAST…

WDPN33 PGTW 082100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 27W (KOGUMA) WARNING NR 016// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 18.1N 157.7E INITIAL INTENSITY: 75 KTS GEOGRAPHIC REFERENCE: 706 NM EAST-NORTHEAST OF SAIPAN MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 12 KTS SIGNIFICANT WAVE HEIGHT: 28 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: TY 27W HAS STEADILY INTENSIFIED OVER THE PAST SIX HOURS AND ENVIRONMENTAL CONDITIONS HAVE BECOME INCREASINGLY SUPPORTIVE OF RAPID INTENSIFICATION. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A NASCENT EYE FEATURE BEGINNING TO DEVELOP WITHIN AN INCREASINGLY ORGANIZED AND SYMMETRIC RING OF DEEP CONVECTION AROUND THE CENTER. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON RECENT TIGHTLY CLUSTERED SATELLITE POSITION FIXES FROM PGTW, RJTD, AND RCTP. THE INITIAL INTENSITY OF 75 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON A CONSENSUS OF THE SUBJECTIVE DVORAK AND AUTOMATED INTENSITY ESTIMATES LISTED BELOW. THERE IS SOME UNCERTAINTY IN THE INITIAL INTENSITY, AND CONSEQUENT SPREAD AMONG INDIVIDUAL INTENSITY ESTIMATES, GIVEN THE RAPID STRUCTURAL CHANGES OBSERVED IN RECENT SATELLITE IMAGERY. INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK AND PERSISTENCE CURRENT STEERING MECHANISM: DEEP-LAYER SUBTROPICAL RIDGE (STR) TO THE NORTHEAST AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T4.5 - 77 KTS RJTD: T4.5 - 77 KTS RCTP: T4.0 - 65 KTS CIMSS SATCON: 63 KTS AT 081447Z CIMSS ADT: 59 KTS AT 081730Z CIMSS AIDT: 55 KTS AT 081730Z CIMSS D-MINT: 85 KTS AT 081832Z CIMSS D-PRINT: 75 KTS AT 081900Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY FAVORABLE VWS: 5-10 KTS SST: 29-30 CELSIUS OUTFLOW: STRONG POLEWARD ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM 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 27W WILL CONTINUE TO TRACK ALONG THE PERIPHERY OF THE CURRENT SUBTROPICAL STEERING RIDGE THROUGH THE 120 HOUR FORECAST PERIOD, GRADUALLY TURNING POLEWARD AND EASTWARD AHEAD OF A DEVELOPING MID-LATITUDE TROUGH AS IT ROUNDS THE RIDGE AXIS. RAPID INTENSIFICATION IS VERY LIKELY IN THE NEAR-TERM WITH FAVORABLY LOW VERTICAL WIND SHEAR, STRONG OUTFLOW ALOFT, PASSAGE OVER VERY WARM WATER, AND A PRIMED STORM STRUCTURE SUPPORTING THE TREND. BY TAU 72, ALONG-TRACK OCEAN HEAT CONTENT WILL BEGIN TO DROP AND THE SYSTEM WILL FEEL THE EFFECTS OF INCREASING VERTICAL WIND SHEAR AND A LESS FAVORABLE OUTFLOW PATTERN, INITIATING A WEAKENING TREND. IN THAT EXTENDED PERIOD, THE SYSTEM WILL ACCELERATE POLEWARD AHEAD OF THE AFOREMENTIONED TROUGH AND BEGIN EXTRATROPICAL TRANSITION BY TAU 120. INTERACTION WITH THE TROUGH IS EXPECTED TO PROVIDE FAVORABLE BAROCLINIC SUPPORT, ENABLING THE SYSTEM TO MAINTAIN TYPHOON INTENSITY AS IT TRANSITIONS TO A MIDLATITUDE LOW. MODEL DISCUSSION: NUMERICAL MODEL TRACK FORECAST TRENDS ARE CONSISTENT WITH THE PREVIOUS CYCLE. WHILE ALL GUIDANCE IS IN GOOD AGREEMENT WITH THE OVERALL STEERING SCENARIO, SPREAD INCREASES AFTER TAU 72. THE CONSENSUS OF PHYSICS-BASED MODELS DEPICTS A TIGHTER TURN TOWARD THE NORTH-NORTHEAST THAN THE AI-BASED CONSENSUS. HOWEVER, BOTH THE LATEST ECMWF AND GFS SOLUTIONS LIE MORE IN LINE WITH THE AI-MODEL GUIDANCE, AND THE FULL GROUPING OF THE GFS, ECMWF, AND AI-MODELS REPRESENT A SCENARIO IN WHICH THE STEERING RIDGE AMPLIFIES FARTHER POLEWARD AHEAD OF AN APPROACHING MID-LATITUDE TROUGH IN THE EXTENDED RANGE THAN PREDICTED BY THE OTHER SOLUTIONS. THE CURRENT JTWC TRACK FORECAST FAVORS THE GFS-ECMWF-AI GROUPING AND IS CONSISTENT WITH THE PREVIOUS FORECAST WITH HIGH CONFIDENCE THROUGH TAU 72 AND MEDIUM CONFIDENCE THEREAFTER.…