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Hurricane Nora Forecast Discussion Number 11

2021-08-28 11:00:40| National Hurricane Center (East Pacific)

Issued at 400 AM CDT Sat Aug 28 2021 000 WTPZ44 KNHC 280900 TCDEP4 Hurricane Nora Discussion Number 11 NWS National Hurricane Center Miami FL EP142021 400 AM CDT Sat Aug 28 2021 The inner-core structure appears to be tightening up with Nora this morning. Deep convection with tops colder than -70 C has been blossoming and wrapping around the center, first around the eastern side, but more recently in all quadrants as a distinct warm spot denotes the center. Earlier, there was a helpful SSMIS microwave pass at 0143 UTC that showed a closed cyan ring on the 37 GHz channel, which is a signal often related to a formative low-level eyewall and is often a harbinger for significant intensification. An ASCAT-B pass at 0403 UTC also suggested the wind-radii were gradually contracting, and also that the center position is a little further east of the short-term track. The latest subjective Dvorak estimates at 0600 UTC from SAB and TAFB have both increased to T4.0/65 kt. These estimates, in addition to the recent structural improvements in IR satellite and microwave imagery, support raising the intensity to 65-kt for this advisory, making Nora a hurricane. Nora continues to move a little more poleward this morning, with the latest motion estimate at 345 degrees at 9 kt. While the track forecast philosophy hasn't changed much over the last day, as a weakening mid-level ridge provides a weakness for Nora to escape north-northwestward, there has been a notable eastward shift in the track guidance. The deterministic ECMWF run, for instance, is now showing the hurricane brushing the shoreline of Mainland Mexico near Cabo Corrientes in 24 hours, and is now quite similar to the latest GFS forecast. The ECMWF ensembles have also shifted further east, with around half of the members explicitly showing landfall over mainland Mexico. The latest NHC track forecast has thus been shifted eastward, especially during the first 24-48 hours of the forecast, but I did not want to shift Nora's track as far east as the latest HCCA and TVCE consensus aids and further eastward adjustments may be necessary in subsequent forecasts. Afterwards, if Nora remains intact, the guidance shows the system bending back to the northwest and running up the gap of the Gulf of California between Baja California Sur and Mainland Mexico. Now that Nora appears to developing an inner core, at least steady intensification is expected in the short-term while the hurricane remains far enough offshore of mainland Mexico in a favorable dynamic and thermodynamic environment. After 12 hours, the intensity forecast becomes very tricky, due to just how much land interaction Nora will encounter as it brushes by Mexico. Once again, a lot of the reliable intensity guidance shows substantial land interaction and are sharply lower after 24 hours. Because the latest forecast track has been shifted further east, it increases the chance that significant disruption of the storm may occur by the mountainous terrain located near the coast of Mexico in that location. The latest intensity forecast was lowered after 24 hours and held at 70 kt through 96 hours due to this large uncertainty tied to possible land interaction. The latest forecast remains higher than the majority of the guidance, but is lower than the previous forecast. The wind radii have also been adjusted smaller after 24 hours, as the global model guidance suggests that the TC wind field will shrink quite dramatically as the system tracks near mainland Mexico. Tropical Storm and Hurricane Warnings have been extended further north along the mainland Mexico coastline given the eastward adjustments in the latest forecast track. Key Messages: 1. Nora is forecast strengthen today as it approaches the coasts of the Mexican states of Jalisco and Nayarit, and hurricane warnings are in effect for portions of that coastline. Interests in these areas and points further north should closely monitor the progress of Nora and subsequent updates to the forecast. 2.Heavy rain associated with Nora is expected across coastal sections of the Mexican states of Guerrero, Michoacan, Colima, Jalisco and Nayarit, as well as Baja California Sur. Life-threatening flash flooding and mudslides are expected. As Nora lifts northwest, heavy rainfall will spread into the Mexican states of Sinaloa and Sonora as well as the southwestern U.S. during the middle to latter portion of next week. 3. Nora is forecast to move over the Gulf of California as a hurricane early next week, bringing a risk of wind and rain impacts to portions of the Mexican states of Baja California Sur, Sinaloa, and Sonora. Given the above-average uncertainty in the forecast intensity, confidence is not high enough to determine the magnitude and location of these potential impacts. FORECAST POSITIONS AND MAX WINDS INIT 28/0900Z 17.1N 105.2W 65 KT 75 MPH 12H 28/1800Z 18.8N 105.5W 75 KT 85 MPH 24H 29/0600Z 20.8N 106.1W 75 KT 85 MPH...NEAR MAINLAND MEXICO 36H 29/1800Z 22.4N 107.0W 70 KT 80 MPH 48H 30/0600Z 23.3N 107.8W 70 KT 80 MPH 60H 30/1800Z 24.1N 108.6W 70 KT 80 MPH 72H 31/0600Z 24.9N 109.4W 70 KT 80 MPH 96H 01/0600Z 26.4N 110.6W 70 KT 80 MPH 120H 02/0600Z 28.7N 111.0W 45 KT 50 MPH...INLAND $$ Forecaster Papin/Beven

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Hurricane Ida Forecast Discussion Number 8

2021-08-28 10:59:39| National Hurricane Center (Atlantic)

Issued at 400 AM CDT Sat Aug 28 2021 000 WTNT44 KNHC 280859 TCDAT4 Hurricane Ida Discussion Number 8 NWS National Hurricane Center Miami FL AL092021 400 AM CDT Sat Aug 28 2021 Just after the last advisory, the convective structure of Ida got a bit ragged, probably due to the residual effects of land interaction with Cuba and a tongue of dry air that wrapped into the eastern side of the circulation. However, latest radar images from Cuba show that the eye is becoming better defined, and satellite imagery shows cooling of the cloud tops in the eyewall. The initial intensity has been held at 70 kt based on the latest trends and earlier Hurricane Hunter aircraft data. NOAA and Air Force reserve Hurricane Hunter aircraft are scheduled to investigate Ida again starting around 12Z. The initial motion remains northwestward or 315/14. A subtropical ridge centered off the southeast U.S. coast is expected to shift westward through the weekend, and this feature should continue to provide a steering flow that will take Ida steadily northwestward across the Gulf of Mexico during the next 36-48 h. The track guidance remains in good agreement that Ida will make landfall on the coast of southeastern or central Louisiana late Sunday or early Monday morning. After landfall, Ida is expected to turn northward through Louisiana and western Mississippi at a slower forward speed as it moves around the western end of the ridge. Recurvature into the westerlies and an east-northeastward motion are expected by the end of the forecast period. The new forecast track is nudged slightly to the west after 36 h to keep it near the various consensus models, but this is not a significant change from the previous forecast. Users are again reminded to not focus on the exact details of the track forecast as storm surge, wind, and rainfall impacts will extend far from the center. Ida is expected to remain in a favorable environment of light vertical shear and very warm sea-surface temperatures until it makes landfall. The only negative factor is the possibility that dry air may try to entrain into the system and slow the expected intensification. The SHIPS and LGEM models are showing a little less strengthening than previously. However, the HWRF and HMON models continue to forecast Ida to reach Category 4 intensity before landfall. The new intensity forecast will forecast a peak intensity of 120 kt in best agreement with the HWRF and HMON, and the pre-landfall part of the forecast is little changed from the previous forecast. After landfall, rapid weakening is expected due to land interaction, drier air, and an increase in shear, and Ida is expected to become a post-tropical cyclone as it moves through the Tennessee Valley. As Ida continues to intensify over the Gulf of Mexico, an expansion of its wind field is predicted. The NHC wind radii forecast is largely based on the radii consensus, and winds of at least tropical storm force are likely to reach the coast Sunday morning. Therefore, all preparations to protect life and property for this dangerous event need to be made today. Key Messages: 1. Hurricane and tropical storm conditions are ending over Cuba. However, Ida will continue to bring periods of heavy rain across western Cuba through today that may lead to flash flooding and mudslides. 2. There is a danger of life-threatening storm surge inundation Sunday along the coasts of Louisiana and Mississippi within the Storm Surge Warning area. Extremely life-threatening inundation of 10 to 15 feet above ground level is possible within the area from Morgan City, Louisiana, to the Mouth of the Mississippi River. Interests throughout the warning area should follow any advice given by local officials. 3. Ida is expected to be an extremely dangerous major hurricane when it reaches the coast of Louisiana. Hurricane-force winds are expected Sunday in portions of the Hurricane Warning area along the Louisiana coast, including metropolitan New Orleans, with potentially catastrophic wind damage possible where the core of Ida moves onshore. Actions to protect life and property should be rushed to completion in the warning area. 4. Ida is likely to produce heavy rainfall later Sunday into Monday across the central Gulf Coast from southeast Louisiana to coastal Mississippi resulting in significant flash and riverine flooding impacts. As Ida moves inland, flooding impacts are possible across portions of the Lower Mississippi and Tennessee Valleys. FORECAST POSITIONS AND MAX WINDS INIT 28/0900Z 24.0N 85.2W 70 KT 80 MPH 12H 28/1800Z 25.4N 86.9W 85 KT 100 MPH 24H 29/0600Z 27.1N 88.9W 105 KT 120 MPH 36H 29/1800Z 28.6N 90.5W 120 KT 140 MPH 48H 30/0600Z 30.1N 91.3W 85 KT 100 MPH...INLAND 60H 30/1800Z 31.6N 91.2W 45 KT 50 MPH...INLAND 72H 31/0600Z 33.2N 90.5W 30 KT 35 MPH...INLAND 96H 01/0600Z 36.0N 87.0W 25 KT 30 MPH...INLAND 120H 02/0600Z 37.5N 82.5W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ Forecaster Beven

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Hurricane Ida Forecast Advisory Number 8

2021-08-28 10:58:08| National Hurricane Center (Atlantic)

Issued at 0900 UTC SAT AUG 28 2021 000 WTNT24 KNHC 280858 TCMAT4 HURRICANE IDA FORECAST/ADVISORY NUMBER 8 NWS NATIONAL HURRICANE CENTER MIAMI FL AL092021 0900 UTC SAT AUG 28 2021 CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY... THE GOVERNMENT OF CUBA HAS DISCONTINUED ALL WARNINGS FOR CUBA. SUMMARY OF WATCHES AND WARNINGS IN EFFECT... A STORM SURGE WARNING IS IN EFFECT FOR... * EAST OF ROCKEFELLER WILDLIFE REFUGE LOUISIANA TO THE MISSISSIPPI/ALABAMA BORDER * VERMILION BAY...LAKE BORGNE...LAKE PONTCHARTRAIN...AND LAKE MAUREPAS A HURRICANE WARNING IS IN EFFECT FOR... * INTRACOASTAL CITY LOUISIANA TO THE MOUTH OF THE PEARL RIVER * LAKE PONTCHARTRAIN...LAKE MAUREPAS...AND METROPOLITAN NEW ORLEANS A STORM SURGE WATCH IS IN EFFECT FOR... * SABINE PASS TO ROCKEFELLER WILDLIFE REFUGE LOUISIANA * MOBILE BAY A HURRICANE WATCH IS IN EFFECT FOR... * CAMERON LOUISIANA TO WEST OF INTRACOASTAL CITY LOUISIANA * MOUTH OF THE PEARL RIVER TO THE MISSISSIPPI/ALABAMA BORDER A TROPICAL STORM WARNING IS IN EFFECT FOR... * CAMERON LOUISIANA TO WEST OF INTRACOASTAL CITY LOUISIANA * MOUTH OF THE PEARL RIVER TO THE MISSISSIPPI/ALABAMA BORDER A TROPICAL STORM WATCH IS IN EFFECT FOR... * MISSISSIPPI/ALABAMA BORDER TO THE ALABAMA/FLORIDA BORDER A STORM SURGE WARNING MEANS THERE IS A DANGER OF LIFE-THREATENING INUNDATION...FROM RISING WATER MOVING INLAND FROM THE COASTLINE...DURING THE NEXT 36 HOURS IN THE INDICATED LOCATIONS. FOR A DEPICTION OF AREAS AT RISK...PLEASE SEE THE NATIONAL WEATHER SERVICE STORM SURGE WATCH/WARNING GRAPHIC...AVAILABLE AT HURRICANES.GOV. THIS IS A LIFE-THREATENING SITUATION. PERSONS LOCATED WITHIN THESE AREAS SHOULD TAKE ALL NECESSARY ACTIONS TO PROTECT LIFE AND PROPERTY FROM RISING WATER AND THE POTENTIAL FOR OTHER DANGEROUS CONDITIONS. PROMPTLY FOLLOW EVACUATION AND OTHER INSTRUCTIONS FROM LOCAL OFFICIALS. A HURRICANE WARNING MEANS THAT HURRICANE CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA. A WARNING IS TYPICALLY ISSUED 36 HOURS BEFORE THE ANTICIPATED FIRST OCCURRENCE OF TROPICAL-STORM-FORCE WINDS...CONDITIONS THAT MAKE OUTSIDE PREPARATIONS DIFFICULT OR DANGEROUS. PREPARATIONS TO PROTECT LIFE AND PROPERTY SHOULD BE RUSHED TO COMPLETION. A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA WITHIN 36 HOURS. A STORM SURGE WATCH MEANS THERE IS A POSSIBILITY OF LIFE- THREATENING INUNDATION...FROM RISING WATER MOVING INLAND FROM THE COASTLINE...IN THE INDICATED LOCATIONS DURING THE NEXT 48 HOURS. A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA. A WATCH IS TYPICALLY ISSUED 48 HOURS BEFORE THE ANTICIPATED FIRST OCCURRENCE OF TROPICAL-STORM-FORCE WINDS...CONDITIONS THAT MAKE OUTSIDE PREPARATIONS DIFFICULT OR DANGEROUS. A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 48 HOURS. INTERESTS ELSEWHERE ALONG THE NORTHERN U.S. GULF COAST SHOULD MONITOR THE PROGRESS OF THIS SYSTEM. HURRICANE CENTER LOCATED NEAR 24.0N 85.2W AT 28/0900Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 315 DEGREES AT 14 KT ESTIMATED MINIMUM CENTRAL PRESSURE 987 MB EYE DIAMETER 25 NM MAX SUSTAINED WINDS 70 KT WITH GUSTS TO 85 KT. 64 KT....... 20NE 0SE 0SW 0NW. 50 KT....... 50NE 30SE 0SW 30NW. 34 KT.......100NE 60SE 40SW 70NW. 12 FT SEAS..120NE 60SE 60SW 120NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 24.0N 85.2W AT 28/0900Z AT 28/0600Z CENTER WAS LOCATED NEAR 23.5N 84.7W FORECAST VALID 28/1800Z 25.4N 86.9W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 20NE 15SE 10SW 20NW. 50 KT... 50NE 40SE 20SW 40NW. 34 KT...110NE 80SE 60SW 90NW. FORECAST VALID 29/0600Z 27.1N 88.9W MAX WIND 105 KT...GUSTS 130 KT. 64 KT... 20NE 20SE 15SW 20NW. 50 KT... 60NE 50SE 30SW 40NW. 34 KT...120NE 100SE 70SW 100NW. FORECAST VALID 29/1800Z 28.6N 90.5W MAX WIND 120 KT...GUSTS 145 KT. 64 KT... 35NE 30SE 20SW 30NW. 50 KT... 60NE 60SE 30SW 50NW. 34 KT...130NE 110SE 80SW 110NW. FORECAST VALID 30/0600Z 30.1N 91.3W...INLAND MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 30NE 30SE 20SW 20NW. 50 KT... 60NE 60SE 40SW 40NW. 34 KT...110NE 110SE 70SW 60NW. FORECAST VALID 30/1800Z 31.6N 91.2W...INLAND MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 50NE 100SE 40SW 30NW. FORECAST VALID 31/0600Z 33.2N 90.5W...INLAND MAX WIND 30 KT...GUSTS 40 KT. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 01/0600Z 36.0N 87.0W...INLAND MAX WIND 25 KT...GUSTS 35 KT. OUTLOOK VALID 02/0600Z 37.5N 82.5W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 24.0N 85.2W INTERMEDIATE PUBLIC ADVISORY...WTNT34 KNHC/MIATCPAT4...AT 28/1200Z NEXT ADVISORY AT 28/1500Z $$ FORECASTER BEVEN

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Hurricane Nora Forecast Advisory Number 11

2021-08-28 10:58:08| National Hurricane Center (East Pacific)

Issued at 0900 UTC SAT AUG 28 2021 000 WTPZ24 KNHC 280858 TCMEP4 HURRICANE NORA FORECAST/ADVISORY NUMBER 11 NWS NATIONAL HURRICANE CENTER MIAMI FL EP142021 0900 UTC SAT AUG 28 2021 CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY... THE GOVERNMENT OF MEXICO HAS ISSUED A HURRICANE WARNING NORTH OF CABO CORRIENTES TO SAN BLAS MEXICO. THE GOVERNMENT OF MEXICO HAS ALSO ISSUED A HURRICANE WATCH FROM NORTH OF SAN BLAS TO MAZATLAN MEXICO...AND HAS UPGRADED THE TROPICAL STORM WATCH TO A WARNING. SUMMARY OF WATCHES AND WARNINGS IN EFFECT... A HURRICANE WARNING IS IN EFFECT FOR... * MANZANILLO NORTHWARD TO SAN BLAS MEXICO A HURRICANE WATCH IS IN EFFECT FOR... * LAZARO CARDENAS TO SOUTH OF MANZANILLO MEXICO * NORTH OF SAN BLAS TO MAZATLAN MEXICO A TROPICAL STORM WARNING IS IN EFFECT FOR... * TECPAN DE GALEANA TO MANZANILLO MEXICO * NORTH SAN BLAS TO MAZATLAN MEXICO A HURRICANE WARNING MEANS THAT HURRICANE CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA...IN THIS CASE WITHIN THE NEXT 12-24 HOURS. PREPARATIONS TO PROTECT LIFE AND PROPERTY SHOULD BE RUSHED TO COMPLETION. A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA...IN THIS CASE WITHIN THE NEXT 12-24 HOURS. A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA...IN THIS CASE OVER THE NEXT 24-36 HOURS. INTERESTS ELSEWHERE FURTHER UP ALONG THE NORTHWESTERN COAST OF MAINLAND MEXICO AND SOUTHERN PORTIONS OF BAJA CALIFORNIA SUR SHOULD MONITOR THE PROGRESS OF NORA. ADDITIONAL WATCHES AND WARNINGS MAY BE REQUIRED FOR PORTIONS OF THESE AREAS TONIGHT OR ON SATURDAY. HURRICANE CENTER LOCATED NEAR 17.1N 105.2W AT 28/0900Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE NORTH-NORTHWEST OR 345 DEGREES AT 9 KT ESTIMATED MINIMUM CENTRAL PRESSURE 983 MB MAX SUSTAINED WINDS 65 KT WITH GUSTS TO 80 KT. 64 KT....... 30NE 0SE 0SW 0NW. 50 KT....... 50NE 70SE 0SW 50NW. 34 KT.......180NE 150SE 120SW 140NW. 12 FT SEAS..240NE 360SE 180SW 210NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 17.1N 105.2W AT 28/0900Z AT 28/0600Z CENTER WAS LOCATED NEAR 16.7N 105.0W FORECAST VALID 28/1800Z 18.8N 105.5W MAX WIND 75 KT...GUSTS 90 KT. 64 KT... 30NE 20SE 0SW 0NW. 50 KT... 50NE 60SE 30SW 30NW. 34 KT...100NE 120SE 80SW 90NW. FORECAST VALID 29/0600Z 20.8N 106.1W...NEAR MAINLAND MEXICO MAX WIND 75 KT...GUSTS 90 KT. 64 KT... 25NE 20SE 0SW 0NW. 50 KT... 40NE 40SE 30SW 30NW. 34 KT... 80NE 80SE 60SW 80NW. FORECAST VALID 29/1800Z 22.4N 107.0W MAX WIND 70 KT...GUSTS 85 KT. 64 KT... 20NE 20SE 0SW 0NW. 50 KT... 40NE 40SE 30SW 30NW. 34 KT... 70NE 80SE 50SW 50NW. FORECAST VALID 30/0600Z 23.3N 107.8W MAX WIND 70 KT...GUSTS 85 KT. 64 KT... 15NE 15SE 15SW 15NW. 50 KT... 30NE 30SE 30SW 30NW. 34 KT... 60NE 60SE 50SW 50NW. FORECAST VALID 30/1800Z 24.1N 108.6W MAX WIND 70 KT...GUSTS 85 KT. 50 KT... 30NE 30SE 20SW 20NW. 34 KT... 70NE 60SE 60SW 60NW. FORECAST VALID 31/0600Z 24.9N 109.4W MAX WIND 70 KT...GUSTS 85 KT. 50 KT... 20NE 20SE 20SW 20NW. 34 KT... 50NE 40SE 30SW 30NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 125 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 01/0600Z 26.4N 110.6W MAX WIND 70 KT...GUSTS 85 KT. OUTLOOK VALID 02/0600Z 28.7N 111.0W...INLAND MAX WIND 45 KT...GUSTS 55 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.1N 105.2W INTERMEDIATE PUBLIC ADVISORY...WTNT34 KNHC/MIATCPEP4...AT 28/1200Z NEXT ADVISORY AT 28/1500Z $$ FORECASTER PAPIN/BEVEN

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Tropical Depression Ten Forecast Discussion Number 1

2021-08-28 10:55:08| National Hurricane Center (Atlantic)

Issued at 500 AM AST Sat Aug 28 2021 000 WTNT45 KNHC 280855 TCDAT5 Tropical Depression Ten Discussion Number 1 NWS National Hurricane Center Miami FL AL102021 500 AM AST Sat Aug 28 2021 The tropical wave and associated low pressure system that the NHC has been tracking for the past several days has finally acquired a well-defined surface circulation and enough organized deep convection to be classified as a tropical depression. The last few visible satellite images yesterday evening indicated a tight swirl in the low-cloud field and a 27/2325Z partial ASCAT-A pass showed the circulation was also well-defined, albeit with only 23-kt surface winds. Since the time of that scatterometer pass, however, a significant increase in deep convection with cloud tops colder than -80 deg C has developed very near and to the northeast of he center, with a few cells also now having developed just to the southwest of the center. Based on the structure noted in the ASCAT data and the pronounced increase in the amount and organization of the convection, the advisory intensity is estimated to be 30 kt. The initial motion estimate is 340/06 kt. The system has slowed down markedly during the past several hours, likely due to the sharp increase in the associated convection. A turn toward the north is forecast to begin later this afternoon as the system moves into a break in the Atlantic subtropical ridge pattern, with a general northward motion continuing through the remainder of the forecast period. The latest NHC model guidance is surprisingly in good agreement on this track scenario, with only minor forward speed differences noted between the models. The 18-20 kt of westerly vertical wind shear affecting the depression is expected to abate somewhat during the next 12-24 hours, which should allow for some slight strengthening to occur while the system moves over 27.5 deg C sea-surface temperatures. By 48 hours, however, the shear is forecast to increase again in excess of 25 kt, which should act to weaken the cyclone, possibly even causing it to degenerate into a remnant low. For now, however, the official intensity forecast calls for the system to remain a tropical depression at days 3 and 4 in the event the cyclone regenerates at day 5 when the shear is forecast to decrease below 10 kt, which may allow for convection to redevelop. The official intensity forecast closely follows a blend of the intensity consensus models IVCN and NOAA-HCCA. FORECAST POSITIONS AND MAX WINDS INIT 28/0900Z 14.0N 49.9W 30 KT 35 MPH 12H 28/1800Z 14.8N 50.3W 35 KT 40 MPH 24H 29/0600Z 16.1N 50.3W 35 KT 40 MPH 36H 29/1800Z 17.7N 50.2W 35 KT 40 MPH 48H 30/0600Z 19.1N 50.0W 30 KT 35 MPH 60H 30/1800Z 20.7N 49.7W 30 KT 35 MPH 72H 31/0600Z 21.9N 49.7W 30 KT 35 MPH 96H 01/0600Z 24.5N 50.5W 30 KT 35 MPH 120H 02/0600Z 27.5N 52.8W 30 KT 35 MPH $$ Forecaster Stewart

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