Home discussion
 

Keywords :   


Tag: discussion

Tropical Depression Three Forecast Discussion Number 4

2020-06-02 17:04:40| National Hurricane Center (Atlantic)

Issued at 1000 AM CDT Tue Jun 02 2020 000 WTNT43 KNHC 021504 TCDAT3 Tropical Depression Three Discussion Number 4 NWS National Hurricane Center Miami FL AL032020 1000 AM CDT Tue Jun 02 2020 An Air Force Reserve Unit Hurricane Hunter aircraft is currently investigating the depression and has found that the system is very close to tropical storm strength. Based on flight-level and SFMR-observed surface winds from the plane, the intensity is held at 30 kt for now. Since the cyclone is over very warm waters with fairly low vertical shear, intensification to a tropical storm should occur today. The official intensity forecast is close to the model consensus. The intensity forecast later in the period is dependent on how much shear the system will encounter over the northern Gulf of Mexico and this is somewhat uncertain. For now, the intensity forecast will remain conservative. The initial motion estimate is slowly westward, or 270/3 kt. The cyclone is expected to remain in weak steering currents over the Bay of Campeche for the next couple of days, with the system moving slowly within a broader gyre over eastern Mexico. Global models show the cyclone being trapped between two mid-level anticyclones until later in the week, when some increase in southerly flow should begin to carry the system toward the northern Gulf of Mexico coastline. The official track forecast closely follows the dynamical model consensus. At this time, both the track and intensity forecasts are of low confidence. However, for the next couple of days, the main threat from this slow-moving cyclone is from widespread heavy rains over portions of southern Mexico and Central America. Key Messages: 1. Deadly flooding has already occurred in portions of Guatemala and El Salvador, and the depression is expected to bring additional heavy rainfall to portions of southern Mexico, Guatemala, Honduras, and El Salvador, which could cause life-threatening flash flooding and mudslides. Refer to products from your local weather office for more information. 2. Tropical storm conditions are expected along the coast of Mexico where a tropical storm warning is in effect. 3. The system is forecast to begin moving northward across the Gulf of Mexico by this weekend. However, it is too soon to specify the location and timing of any potential impacts along the U.S. Gulf Coast. Interests in these areas should monitor the progress of this system through the week and ensure they have their hurricane plan in place as we begin the season. FORECAST POSITIONS AND MAX WINDS INIT 02/1500Z 19.5N 92.6W 30 KT 35 MPH 12H 03/0000Z 19.5N 92.7W 35 KT 40 MPH 24H 03/1200Z 19.0N 92.4W 40 KT 45 MPH 36H 04/0000Z 18.8N 92.2W 40 KT 45 MPH 48H 04/1200Z 18.8N 92.0W 45 KT 50 MPH 60H 05/0000Z 18.9N 91.8W 40 KT 45 MPH 72H 05/1200Z 19.8N 91.2W 45 KT 50 MPH 96H 06/1200Z 22.0N 91.0W 50 KT 60 MPH 120H 07/1200Z 26.0N 91.0W 55 KT 65 MPH $$ Forecaster Pasch

Tags: number discussion tropical depression

 

Tropical Depression Three Forecast Discussion Number 3

2020-06-02 10:50:04| National Hurricane Center (Atlantic)

Issued at 400 AM CDT Tue Jun 02 2020 785 WTNT43 KNHC 020849 TCDAT3 Tropical Depression Three Discussion Number 3 NWS National Hurricane Center Miami FL AL032020 400 AM CDT Tue Jun 02 2020 Satellite data, Mexican radar data from Sabancuy, and nearby surface observations indicate that the depression has become a little better organized and has strengthened slightly since the previous advisory. Radar data indicate a mass of convection has developed north of and over the low-level center, and a broken curved band has also formed in the eastern semicircle. The initial intensity has been increased to 30 kt based on a 0201 UTC ASCAT-A overpass that showed a couple of 27-kt vectors located in the northeastern quadrant outside of the most active convection. An Air Force Reserve reconnaissance aircraft is scheduled to investigate the depression later this morning. The initial motion is westward or 270/02 kt. The latest 00Z model guidance continues to show the depression remaining embedded within the larger Central American gyre for the next few days, with the gyre gradually contracting around the depression, with the two entities merging into one system by 72 hours. Similar to last night, tonight's model runs have again abandoned the development of a secondary low east of the depression and moving it northward toward the U. S Gulf coast. This may be due in part to the lack of Mexican and Central American upper-air data at 0000 UTC, except for the Belize sounding. But the global and regional models are in overall in good agreement on the cyclone remaining trapped in a break in the subtropical ridge to the east and west of the depression. By 72-96 hours, a weak shortwave trough is forecast to drop southward out of the southern plains and into into the ridge weakness and act as a catalyst to nudge the depression slowly northward on days 4 and 5. Until that time, the cyclone is expected to meander over the the Bay of Campeche for the next 2-3 days, possibly making landfall along the coast of extreme southeastern Mexico and the west coast of Yucatan. The new NHC forecast track is similar to the previous advisory track, and brings the center close to the coast of Mexico on days 2 and 3. It should be noted, though, that in 5 days there could be a cyclone near the forecast point that is not actually TD-3 due to land interaction and the possible formation of a secondary cyclone. Although the vertical wind shear is forecast to remain low while the cyclone remains trapped in the Bay of Campeche during the next few days, only slow strengthening is expected due to possible land interaction and intrusions of dry air caused by southwesterly downslope flow coming off of the mountains in the state of Chiapas, which already appears to be underway based on satellite and radar imagery. After the cyclone starts moving northward, increasing southerly shear is expected to inhibit any significant or rapid strengthening. An alternative intensity forecast scenario is that the cyclone moves far enough inland over Mexico to dissipate completely in less than 5 days as forecast by the GFS and HWRF models. Given the complexity of the situation, both the track and intensity forecasts are currently low confidence. However, either of the current scenarios will result in widespread heavy rains over portions of southern Mexico and Central America. Key Messages: 1. Deadly flooding has already been occurring in portions of Guatemala and El Salvador. The depression is expected to bring heavy rainfall to portions of southern Mexico, Guatemala, Honduras and El Salvador, which could cause life-threatening flash flooding and mudslides. Refer to products from your local weather office for more information. 2. Tropical storm conditions are expected along the coast of Mexico where a tropical storm warning is in effect. 3. The system is forecast to begin moving northward across the Gulf of Mexico later this week. However, it is too soon to specify the location and timing of any potential impacts along the U.S. Gulf Coast. Interests in these areas should monitor the progress of this system through the week and ensure they have their hurricane plan in place as we begin the season. FORECAST POSITIONS AND MAX WINDS INIT 02/0900Z 19.6N 92.1W 30 KT 35 MPH 12H 02/1800Z 19.5N 92.4W 35 KT 40 MPH 24H 03/0600Z 19.1N 92.7W 40 KT 45 MPH 36H 03/1800Z 18.8N 92.7W 40 KT 45 MPH 48H 04/0600Z 18.7N 92.5W 45 KT 50 MPH 60H 04/1800Z 19.0N 92.3W 45 KT 50 MPH 72H 05/0600Z 19.3N 92.1W 45 KT 50 MPH 96H 06/0600Z 20.7N 91.7W 50 KT 60 MPH 120H 07/0600Z 23.5N 91.2W 55 KT 65 MPH $$ Forecaster Stewart

Tags: number discussion tropical depression

 
 

Tropical Depression Three Forecast Discussion Number 2

2020-06-02 04:35:03| National Hurricane Center (Atlantic)

Issued at 1000 PM CDT Mon Jun 01 2020 000 WTNT43 KNHC 020234 TCDAT3 Tropical Depression Three Discussion Number 2 NWS National Hurricane Center Miami FL AL032020 1000 PM CDT Mon Jun 01 2020 Satellite imagery, along with radar and surface data from Mexico, indicate that the depression has changed little in organization or strength since the previous advisory. There are a couple of small clusters of convection near the center, while the more concentrated convection is occurring in ragged bands well removed from the center. The initial intensity remains 25 kt based on the surface data and continuity from the previous advisory. The initial motion is now westward or 270/6. The evolution of this system during the next several days remains quite uncertain. The Canadian and UKMET models forecast the cyclone to make a slow counter-clockwise loop inside a larger gyre over Central America during the next 2-3 days, with the center moving near the coast of the Bay of Campeche. This would be followed by a more northward motion with some increase in forward speed as a mid-/upper-level trough develops over the northern Gulf of Mexico. On the other hand, the GFS and ECMWF show the depression turning southward and making landfall over the coast of Mexico in the next 24-36 h, followed by dissipation. These two models subsequently develop a second low pressure area northwest of the Yucatan Peninsula at around 120 h due to the interaction of the aforementioned gyre and trough. The new forecast track follows the previous forecast in showing TD-3 as being the system that moves northward across the Gulf. However, the new track brings the center closer to the coast of Mexico and is slower to move it northward than in the previous advisory. It should be noted, though, that in 5 days there could be a cyclone near the forecast point that is not actually TD-3. In the current track forecast scenario, slow strengthening should occur during the next 24-48 h while the cyclone moves over the warm water of the Bay of Campeche in an environment of light to moderate shear. After time, proximity to the Mexican coast should limit strengthening, and it is possible that the current forecast intensities could be generous. The more northward motion near the end of the forecast period is likely to be accompanied by an increase in southerly shear, so only modest intensification is forecast during that time. Overall, the new intensity forecast is similar to the previous forecast. An alternative intensity forecast scenario is that the cyclone moves far enough inland over Mexico to dissipate completely in less than 5 days as forecast by the GFS and ECMWF. Given the complexity of the situation, both the track and intensity forecasts are currently low confidence. However, either of the current scenarios will result in widespread heavy rains over portions of southern Mexico and Central America. Key Messages: 1. The depression is expected to bring heavy rainfall to portions of southern Mexico, Guatemala, Honduras and El Salvador, which could cause life-threatening flash flooding and mudslides. Refer to products from your local weather office for more information. 2. Tropical storm conditions are expected along the coast of Mexico where a tropical storm warning is in effect. 3. The system is forecast to begin moving northward across the Gulf of Mexico later this week. However, it is too soon to specify the location and timing of any potential impacts along the U.S. Gulf Coast. Interests in these areas should monitor the progress of this system through the week and ensure they have their hurricane plan in place as we begin the season. FORECAST POSITIONS AND MAX WINDS INIT 02/0300Z 19.6N 91.9W 25 KT 30 MPH 12H 02/1200Z 19.6N 92.6W 30 KT 35 MPH 24H 03/0000Z 19.2N 92.8W 35 KT 40 MPH 36H 03/1200Z 18.8N 93.0W 40 KT 45 MPH 48H 04/0000Z 18.6N 93.1W 45 KT 50 MPH 60H 04/1200Z 18.5N 93.2W 45 KT 50 MPH 72H 05/0000Z 18.5N 93.0W 45 KT 50 MPH 96H 06/0000Z 19.5N 92.5W 45 KT 50 MPH 120H 07/0000Z 22.0N 91.5W 50 KT 60 MPH $$ Forecaster Beven

Tags: number discussion tropical depression

 

Tropical Depression Three Forecast Discussion Number 1

2020-06-01 23:01:01| National Hurricane Center (Atlantic)

Issued at 400 PM CDT Mon Jun 01 2020 000 WTNT43 KNHC 012100 TCDAT3 Tropical Depression Three Discussion Number 1 NWS National Hurricane Center Miami FL AL032020 400 PM CDT Mon Jun 01 2020 Recent satellite data and surface observations from Mexico show that the circulation associated with the area of disturbed weather over the Yucatan peninsula has become better defined during the past several hours, and that the center has moved over the eastern portion of the Bay of Campeche. Although the deep convection has waned somewhat, there is evidence of banding in both visible satellite imagery and recent radar data from Sabancuy, Mexico. Based on these data, advisories are being issued on a tropical depression. The initial intensity is set at 25 kt, which is in agreement with earlier ASCAT data. The depression will be moving over the warm waters over the Bay of Campeche and upper-level winds are forecast to be generally conducive for strengthening during the next couple of days. The NHC forecast is in line with much of the intensity guidance and calls for the system to become a tropical storm in 12 to 24 hours, with some additional strengthening predicted through 48 hours while the system remains over the southern Bay of Campeche. After that time, the system's intensity will depend on how much it interacts with land. Although the latest runs of the GFS and ECMWF models take the cyclone inland over southern Mexico, the NHC forecast keeps it just offshore and shows the cyclone maintaining tropical storm strength. Later in the period, the guidance suggests that the system could strengthen over the south-central Gulf of Mexico, but the latter portion of the intensity forecast is of low confidence. The depression is moving west-northwestward or 290/6 kt. The system has been moving cyclonically around a larger gyre over Central America during the past couple of days, and while it remains embedded within the gyre it is forecast to turn west-southwestward, and then southward at a slower forward speed over the next couple of days. On this track, the cyclone is expected to move near the southern Bay of Campeche coast during the next day or two, and confidence it that portion of the track forecast is high. After that time, two distinct scenarios emerges. The first is that the cyclone continues moving southward and weakens or dissipates over the rugged terrain over southern Mexico. The latest runs of the ECMWF and GFS favor that scenario. In this scenario, both models show a new system developing near the south-central Gulf of Mexico from another vorticity center that rotates around the larger gyre. The second scenario, favored by the UKMET and some EC ensemble members, is for the depression to eject north-northeast moving into the central Gulf of Mexico by day 5. The NHC forecast favors the latter, but it is certainly possible that this tropical cyclone will move inland and dissipates and a new cyclone formation occurs later this week. The latter portion of both the track and intensity forecast are of quite low confidence. Key Messages: 1. The depression is expected to bring heavy rainfall to portions of southern Mexico, Guatemala, Honduras and El Salvador, which could cause life-threatening flash flooding and mudslides. Refer to products from your local weather office for more information. 2. Tropical storm conditions are expected along the coast of Mexico where a tropical storm warning is in effect. 3. The system is forecast to begin moving northward across the Gulf of Mexico later this week. However, it is too soon to specify the location and timing of any potential impacts along the U.S. Gulf Coast. Interests in these areas should monitor the progress of this system through the week and ensure they have their hurricane plan in place as we begin the season. FORECAST POSITIONS AND MAX WINDS INIT 01/2100Z 19.6N 91.2W 25 KT 30 MPH 12H 02/0600Z 19.8N 92.3W 30 KT 35 MPH 24H 02/1800Z 19.5N 92.8W 35 KT 40 MPH 36H 03/0600Z 19.2N 93.0W 40 KT 45 MPH 48H 03/1800Z 18.8N 93.2W 45 KT 50 MPH 60H 04/0600Z 18.8N 93.2W 45 KT 50 MPH 72H 04/1800Z 18.8N 93.2W 45 KT 50 MPH 96H 05/1800Z 19.0N 92.8W 45 KT 50 MPH 120H 06/1800Z 23.0N 91.0W 50 KT 60 MPH $$ Forecaster Brown

Tags: number discussion tropical depression

 

Remnants of Amanda Forecast Discussion Number 5

2020-05-31 22:36:44| Tropical Depression LIDIA

Issued at 400 PM CDT Sun May 31 2020

Tags: number discussion forecast amanda

 

Sites : [289] [290] [291] [292] [293] [294] [295] [296] [297] [298] [299] [300] [301] [302] [303] [304] [305] [306] [307] [308] next »