je.st
news
Tag: discussion
Hurricane Grace Forecast Discussion Number 32
2021-08-21 10:58:24| National Hurricane Center (Atlantic)
Issued at 400 AM CDT Sat Aug 21 2021 000 WTNT42 KNHC 210858 TCDAT2 Hurricane Grace Discussion Number 32 NWS National Hurricane Center Miami FL AL072021 400 AM CDT Sat Aug 21 2021 Hurricane Grace made landfall around 0600 UTC this morning near Tecolutla, Mexico with estimated maximum sustained winds of 110 kt. The Air Force Reserve Hurricane Hunters investigated the hurricane earlier tonight and found winds supporting an intensity of 105 kt. After the aircraft left the cyclone, the satellite appearance continued to improve with the eye clearing and becoming better-defined. Therefore, it is assumed that some additional strengthening occurred before landfall. Since that time, the inner-core of Grace has moved inland over eastern Mexico and recent radar and satellite images show a pronounced degradation of the eye and eyewall. Based on this trend, the initial advisory intensity has been lowered to 95 kt. Grace is moving a little south of west, or 260/12 kt. A westward motion is forecast to continue through tonight until the cyclone dissipates. The latest NHC track forecast is little changed from the previous one and is in line with the track consensus guidance. The hurricane's forecast motion will take it over the mountainous terrain of interior Mexico today into tonight. Therefore, rapid weakening is expected and the latest NHC intensity forecast for Grace is near the Decay SHIPS guidance. By tonight, the low-level circulation is expected to dissipate over the higher terrain. As mentioned in previous advisories, the mid-level vortex of Grace is forecast to survive the westward passage over Mexico and reach the eastern Pacific late this weekend where a new tropical cyclone is expected to form. Key Messages: 1. Hurricane conditions and dangerous storm surge are likely to continue along portions of the coast of eastern mainland Mexico for the next few hours within the Hurricane Warning area from Puerto Veracruz northward to Cabo Rojo. 2. Through the weekend, heavy rainfall across Veracruz, Puebla, Tlaxcala, Hidalgo, Queretaro, and eastern San Luis Potosi will lead to significant flash and urban flooding, along with the likelihood of mudslides. FORECAST POSITIONS AND MAX WINDS INIT 21/0900Z 20.5N 97.8W 95 KT 110 MPH 12H 21/1800Z 20.2N 99.6W 55 KT 65 MPH...INLAND 24H 22/0600Z 20.1N 101.6W 30 KT 35 MPH...INLAND 36H 22/1800Z...DISSIPATED $$ Forecaster Latto
Tags: number
discussion
grace
forecast
Tropical Storm Henri Forecast Discussion Number 22
2021-08-21 10:53:53| National Hurricane Center (Atlantic)
Issued at 500 AM EDT Sat Aug 21 2021 000 WTNT43 KNHC 210853 TCDAT3 Tropical Storm Henri Discussion Number 22 NWS National Hurricane Center Miami FL AL082021 500 AM EDT Sat Aug 21 2021 An earlier GMI satellite microwave image continued to indicate that Henri's low-level center was still located near the northwestern edge of the convective canopy. However, more recent geostationary satellite imagery shows that the convection is beginning to wrap around the northeastern and eastern portions of the circulation suggesting that the anticipated decrease in shear is occuring, and that Henri may be on the verge of strengthening. The latest subjective satellite intensity estimates from SAB and TAFB remained unchanged so the initial intensity remains 60 kt, in agreement with those estimates and the earlier aircraft data. The next reconnaissance aircraft mission should be in the storm around 1200 UTC this morning. Henri is moving north-northeastward or 015/10 kt. A mid- to upper-level low and associated trough over the Appalachians and Ohio Valley should steer Henri north-northeastward at a faster forward speed today. As Henri moves around the eastern portion of the upper-low, the storm is forecast to turn north-northwestward tonight. This motion will bring the center of Henri near or over portions of Long Island and Southern New England on Sunday and into the northeastern United States Sunday night. After that time, the cyclone should turn east-northeastward as it becomes caught in the mid-latitude westerlies. The latest dynamical model envelope continues to narrow for the first 24 to 36 hours of the forecast period and only small adjustments were needed to that portion of the track. After that time, the guidance has trended to taking Henri farther inland over the Northeastern United States, and the NHC forecast as been modified accordingly. Decreasing shear, upper-level divergence associated with the trough to Henri's west, and warm SSTs should allow the cyclone to strengthen during the next 12-18 hours. Although not explicitly shown in the intensity forecast, Henri could still peak around 75 kt later today or this evening. After that time, cooler waters are likely to cause a gradual reduction in intensity, however, Henri is forecast to be at or near hurricane strength at landfall. Once the center moves inland over the Northeast United States, a faster rate of filling is anticipated. The system is forecast to become post-tropical in about 60 hours, and it will likely dissipate around day 4, if not a little sooner. The updated intensity forecast is near the upper-end of the intensity guidance during the first 12-24 hours, and is close to the Decay-SHIPS model thereafter. Users are reminded to not focus on the exact forecast of the center of Henri since impacts will extend far from the center. Key Messages: 1. Dangerous storm surge inundation is expected to begin late tonight or Sunday in portions of Long Island, Connecticut, Rhode Island, and southeastern Massachusetts, where a Storm Surge Warning has been issued. Dangerous storm surge is possible beginning late tonight or Sunday in western portions of Long Island and Connecticut in the Storm Surge Watch area. Residents in these areas should follow any advice given by local officials. 2. Hurricane conditions are expected to begin late tonight or Sunday in portions of Long Island and Connecticut, where a Hurricane Warning has been issued. Hurricane conditions are possible late tonight or Sunday across portions of Rhode Island. 3. Heavy rainfall may lead to considerable flash, urban, and small stream flooding, along with the potential for widespread minor and isolated moderate river flooding, over portions of Long Island, New England, southeast New York and northern New Jersey. 4. Swells from Henri will continue to affect much of the east coast of the U.S. through the weekend. These swells could cause life-threatening surf and rip currents. FORECAST POSITIONS AND MAX WINDS INIT 21/0900Z 33.1N 73.2W 60 KT 70 MPH 12H 21/1800Z 35.6N 72.3W 70 KT 80 MPH 24H 22/0600Z 38.8N 72.0W 70 KT 80 MPH 36H 22/1800Z 40.9N 72.7W 60 KT 70 MPH...INLAND 48H 23/0600Z 42.1N 73.6W 35 KT 40 MPH...INLAND 60H 23/1800Z 42.8N 73.3W 25 KT 30 MPH...POST-TROP/INLAND 72H 24/0600Z 43.3N 71.5W 25 KT 30 MPH...POST-TROP/INLAND 96H 25/0600Z 44.5N 62.5W 25 KT 30 MPH...POST-TROPICAL 120H 26/0600Z...DISSIPATED $$ Forecaster Brown
Tags: number
discussion
storm
tropical
Hurricane Grace Forecast Discussion Number 31
2021-08-21 05:00:49| National Hurricane Center (Atlantic)
Issued at 1000 PM CDT Fri Aug 20 2021 000 WTNT42 KNHC 210300 TCDAT2 Hurricane Grace Discussion Number 31 NWS National Hurricane Center Miami FL AL072021 1000 PM CDT Fri Aug 20 2021 Hurricane Grace has rapidly intensified this evening. Deep cold convection has been wrapping around the center, with some evidence of mesovorticies rotating within the eyewall following the GOES-16 GLM lightning data. The Air Force Reserve Hurricane Hunters arrived in Grace around 0000 UTC and found that the storm had intensified into Category 2 hurricane with the pressure dropping down to 967 mb, which is a pronounced deepening rate of 2 mb per hour compared to the previous advisory. More recently, the aircraft was able to pass through the northeastern eyewall, and recently found flight level winds up to 115 kt with SFMR winds of 105 kt. These observations support Grace being upgraded to a major hurricane this advisory, with maximum sustained winds of 105 kt. Some additional strengthening is possible while Grace remains over the very warm waters in the Bay of Campeche, though the hurricane should be making landfall tonight within the next 3-6 hours just south of Tuxpan, Mexico. By tomorrow morning, the storm should be well inland, and rapid weakening will likely be underway over the very mountainous terrain of mainland Mexico. The latest NHC intensity forecast now had Grace dissipating over Mexico in about 36 hours. However, as discussed in previous advisories, while the low-level circulation is expected to dissipate, the mid-level vortex is forecast to survive the passage of Mexico, and this feature is likely to lead to the development of a new tropical cyclone in the eastern Pacific basin later this weekend or early next week. Center fixes from the aircraft indicate that Grace has stayed on a mostly due westward heading, at 270/9 kt. This general motion, though with a bit more southward component should continue through landfall and dissipation. This southward deflection over often occurs with strong hurricanes in this region, due to the topographical effects of the wind field to the north ascending over the higher terrain. The official NHC track is very similar to the previous advisory, and remains near the middle of the guidance consensus. Key Messages: 1. Hurricane conditions and dangerous storm surge are likely along portions of the coast of eastern mainland Mexico beginning tonight and tomorrow morning within the Hurricane Warning area from Puerto Veracruz northward to Cabo Rojo. 2. A dangerous storm surge is likely near and to the north of the where the center of Grace crosses the coast of Mexico. 3. Through the weekend, heavy rainfall across Veracruz, Puebla, Tlaxcala, Hidalgo, northern Queretaro, and eastern San Luis Potosi will lead to significant flash and urban flooding, along with the likelihood of mudslides. FORECAST POSITIONS AND MAX WINDS INIT 21/0300Z 20.7N 96.3W 105 KT 120 MPH 12H 21/1200Z 20.3N 97.9W 75 KT 85 MPH...INLAND 24H 22/0000Z 20.0N 100.9W 45 KT 50 MPH...INLAND 36H 22/1200Z...DISSIPATED $$ Forecaster Papin/Beven
Tags: number
discussion
grace
forecast
Tropical Storm Henri Forecast Discussion Number 21
2021-08-21 05:00:19| National Hurricane Center (Atlantic)
Issued at 1100 PM EDT Fri Aug 20 2021 000 WTNT43 KNHC 210300 TCDAT3 Tropical Storm Henri Discussion Number 21 NWS National Hurricane Center Miami FL AL082021 1100 PM EDT Fri Aug 20 2021 Satellite imagery shows that Henri is becoming better organized this evening, with the low-level center becoming more embedded in the convective overcast and an increase in convective banding. There has also been an increase in the anticyclonic outflow. However, reports from Air Force Reserve and NOAA Hurricane Hunter aircraft show that this has not yet resulted in strengthening, as the maximum winds remain about 60 kt to the southeast of the elongated center and the central pressure is in the 994-996 mb range. Henri has turned northward, and the initial motion is now 010/8. A deep-layer mid-latitude trough over the Appalachians and the Ohio Valley will cut off into a closed low during the next 12-24 h, while a ridge builds northward to the east and northeast of Henri. This evolution should cause the storm to move north-northeastward for 12-24 h, followed by a turn toward the north-northwest from 24-48 h. This motion should bring the center of Henri over the mid-Atlantic states or southern New England between 36-48 h. After 48 h, the cyclone should get caught up in the southern edge of the westerlies and turn generally eastward across southern New England and the Gulf of Maine. There has been little change in the direction of the forecast guidance since the last advisory, but the guidance is faster on this cycle through 48 h. Thus, the new track forecast, which lies close to the consensus models, is faster than the previous forecast through the 48 h point. A combination of decreasing shear, improved organization, and upper-level divergence associated with the trough to the west should allow Henri to strengthen for the next 24 h or so, and the new intensity forecast calls for a peak intensity of 75 kt. After 24 h, the center should move over cooler water, and weakening should start before landfall in the northeastern United States. However, the cyclone is still expected to be at or near hurricane intensity at landfall. After landfall, Henri should weaken quickly and become post-tropical by the 72 h time. Dissipation is forecast between 96-120 h. The new intensity forecast follows the overall trend of the intensity guidance. Users are reminded to not focus on the exact forecast of the center of Henri since impacts will extend far from the center. Key Messages: 1. Dangerous storm surge inundation is expected to begin late Saturday night or Sunday in portions of Long Island, Connecticut, Rhode Island, and southeastern Massachusetts, where a Storm Surge Warning has been issued. Dangerous storm surge is possible beginning late Saturday night or Sunday in western portions of Long Island and Connecticut in the Storm Surge Watch area. Residents in these areas should follow any advice given by local officials. 2. Hurricane conditions are expected to begin late Saturday night or Sunday in portions of Long Island and Connecticut, where a Hurricane Warning has been issued. Hurricane conditions are possible late Saturday night or Sunday across portions of Rhode Island and southeastern Massachusetts. 3. Heavy rainfall may lead to considerable flash, urban, and small stream flooding, along with the potential for widespread minor and isolated moderate river flooding, over portions of Long Island and New England Sunday into Monday. 4. Swells from Henri will continue to affect much of the east coast of the U.S. through the weekend. These swells could cause life-threatening surf and rip currents. FORECAST POSITIONS AND MAX WINDS INIT 21/0300Z 32.3N 73.5W 60 KT 70 MPH 12H 21/1200Z 34.3N 72.8W 65 KT 75 MPH 24H 22/0000Z 37.7N 72.1W 75 KT 85 MPH 36H 22/1200Z 40.2N 72.6W 70 KT 80 MPH 48H 23/0000Z 41.4N 73.4W 50 KT 60 MPH...INLAND 60H 23/1200Z 42.2N 73.2W 35 KT 40 MPH...INLAND 72H 24/0000Z 42.7N 72.3W 30 KT 35 MPH...POST-TROP/INLAND 96H 25/0000Z 43.5N 67.0W 25 KT 30 MPH...POST-TROPICAL 120H 26/0000Z...DISSIPATED $$ Forecaster Beven
Tags: number
discussion
storm
tropical
Hurricane Grace Forecast Discussion Number 30
2021-08-20 22:45:15| National Hurricane Center (Atlantic)
Issued at 400 PM CDT Fri Aug 20 2021 000 WTNT42 KNHC 202045 TCDAT2 Hurricane Grace Discussion Number 30 NWS National Hurricane Center Miami FL AL072021 400 PM CDT Fri Aug 20 2021 The satellite presentation of Grace has greatly improved over the past several hours. Deep convection has become more concentrated over the center, and the central dense overcast now appears more symmetric. Dropsonde winds and peak 850-mb flight level wind measured by the Air Force Hurricane Hunters around midday were consistent with an intensity of around 75 kt. However, the surface pressure has been gradually falling throughout the day, and recent satellite data suggest the hurricane is becoming better organized. Therefore, the initial intensity is raised to 80 kt for this advisory, which is supported by the latest UW-CIMSS objective ADT estimate. Given the high oceanic heat content within the southwestern Gulf of Mexico, additional strengthening is expected through Grace's landfall tonight. The 10-15 kt of northerly vertical wind shear over Grace does not appear to be having much of a negative effect on the cyclone at this time. Thus, the official NHC intensity forecast remains on the high end of the guidance envelope, and is closest to the statistical-dynamical models DSHP and LGEM. The current forecast shows Grace making landfall within the next 12-18 h. Once the center of Grace moves inland over the mountains of central Mexico, the cyclone should rapidly weaken and then dissipate by 48 h. However, its remnants appear likely to move into the eastern Pacific and lead to the development of a new tropical cyclone in that basin later this weekend or early next week. Earlier reconnaissance data indicate that Grace has slowed down a bit today, and its initial motion is estimated to be 265/9 kt. This general motion should continue through landfall as Grace is steered by a mid-level ridge over the northern Gulf of Mexico. The official NHC track forecast is slightly slower, but otherwise very similar to the previous one and lies near the center of the guidance envelope. Key Messages: 1. Hurricane conditions and dangerous storm surge are likely along portions of the coast of eastern mainland Mexico beginning this evening within the Hurricane Warning area from Puerto Veracruz northward to Cabo Rojo. 2. Through the weekend, heavy rainfall across Veracruz, Puebla, Tlaxcala, Hidalgo, northern Queretaro, and eastern San Luis Potosi will lead to significant flash and urban flooding, along with the likelihood of mudslides. FORECAST POSITIONS AND MAX WINDS INIT 20/2100Z 20.5N 95.1W 80 KT 90 MPH 12H 21/0600Z 20.4N 96.6W 90 KT 105 MPH...NEAR THE COAST 24H 21/1800Z 19.9N 98.9W 45 KT 50 MPH...INLAND 36H 22/0600Z 19.5N 101.9W 30 KT 35 MPH...INLAND 48H 22/1800Z...DISSIPATED $$ Forecaster Reinhart/Cangialosi
Tags: number
discussion
grace
forecast
Sites : [45] [46] [47] [48] [49] [50] [51] [52] [53] [54] [55] [56] [57] [58] [59] [60] [61] [62] [63] [64] next »