Home › discussion
 

Keywords :   


Tag: discussion

Tropical Depression Fifteen-E Forecast Discussion Number 11

2017-09-14 10:34:19| National Hurricane Center (East Pacific)

Issued at 200 AM PDT Thu Sep 14 2017 000 WTPZ45 KNHC 140834 TCDEP5 Tropical Depression Fifteen-E Discussion Number 11 NWS National Hurricane Center Miami FL EP152017 200 AM PDT Thu Sep 14 2017 The depression continues to be disorganized with the low- and middle-level centers well separated due to shear. This can be clearly observed on conventional imagery as well as microwave data. Given the lack of organization, the initial intensity is kept at 30 kt, and no change in strength is anticipated during the next 24 hours or so. After that time, the shear is forecast to decrease, and the depression could become better organized and reach tropical storm status. This is the scenario provided by most of the guidance. My best estimate of the initial motion is toward the west-northwest or 285 degrees at 4 kt. The depression continues to be trapped within weak steering flow, and only a small westward drift is forecast. In fact, by the end of the forecast period, the steering currents are expected to collapse, and the cyclone will probably begin to meander. The NHC forecast follows most of the guidance up to 4 days. After that time, models diverge considerably and the forecast is highly uncertain. FORECAST POSITIONS AND MAX WINDS INIT 14/0900Z 15.3N 122.2W 30 KT 35 MPH 12H 14/1800Z 15.5N 123.0W 30 KT 35 MPH 24H 15/0600Z 15.5N 124.0W 30 KT 35 MPH 36H 15/1800Z 15.5N 124.8W 35 KT 40 MPH 48H 16/0600Z 15.5N 125.3W 40 KT 45 MPH 72H 17/0600Z 15.5N 125.5W 45 KT 50 MPH 96H 18/0600Z 15.5N 125.5W 50 KT 60 MPH 120H 19/0600Z 16.5N 125.5W 45 KT 50 MPH $$ Forecaster Avila

Tags: number discussion tropical depression

 

Hurricane Jose Forecast Discussion Number 35

2017-09-14 04:44:10| National Hurricane Center (Atlantic)

Issued at 1100 PM AST Wed Sep 13 2017 000 WTNT42 KNHC 140243 TCDAT2 Hurricane Jose Discussion Number 35 NWS National Hurricane Center Miami FL AL122017 1100 PM AST Wed Sep 13 2017 Deep convection appears to have expanded out over the estimated location of the low-level center a bit during the past few hours, and the initial intensity is set to 70 kt based on a blend of the latest Dvorak estimates from TAFB and SAB and the latest UW-CIMSS ADT. Overall, the intensity forecast reasoning has not changed, with moderate shear expected to persist for the next 2-3 days and then increase further late in the period. Slow weakening is expected during the first 24 to 36 hours, followed by little change in intensity during the rest of the forecast period. By day 5, a mid-level trough will likely be supporting Jose with some baroclinic energy to maintain the cyclone's intensity in an environment of higher shear and slightly cooler waters. The new NHC intensity forecast is close to the IVCN consensus aid through the period. The initial motion estimate is a rather uncertain 270/03, as Jose now appears to be moving slowly westward. A building subtropical ridge to the east of Jose will become the dominant steering mechanism through much of the forecast period, with some influence from the above-mentioned upper-level trough by day 5. This pattern should cause Jose to gradually turn poleward during the next 72 hours, with a northward to north-northeastward motion expected by days 4-5. The new NHC track forecast is a little to the left of the previous one at 48 and 72 hours, but is otherwise similar and lies roughly between the GFS and ECMWF models. Jose is producing a large swell field that will affect much of the southwestern Atlantic basin during the next few days, causing rough surf and rip current conditions. FORECAST POSITIONS AND MAX WINDS INIT 14/0300Z 25.2N 66.0W 70 KT 80 MPH 12H 14/1200Z 25.2N 66.5W 65 KT 75 MPH 24H 15/0000Z 25.9N 67.8W 65 KT 75 MPH 36H 15/1200Z 27.0N 69.6W 60 KT 70 MPH 48H 16/0000Z 28.0N 70.8W 60 KT 70 MPH 72H 17/0000Z 30.5N 71.0W 60 KT 70 MPH 96H 18/0000Z 33.7N 69.6W 60 KT 70 MPH 120H 19/0000Z 36.6N 68.7W 60 KT 70 MPH $$ Forecaster Brennan

Tags: number discussion jose forecast

 
 

Tropical Storm Max Forecast Discussion Number 3

2017-09-14 04:39:09| National Hurricane Center (East Pacific)

Issued at 1000 PM CDT Wed Sep 13 2017 000 WTPZ41 KNHC 140238 TCDEP1 Tropical Storm Max Discussion Number 3 NWS National Hurricane Center Miami FL EP162017 1000 PM CDT Wed Sep 13 2017 A 2236Z SSMIS pass showed that Max has a banding mid-level eye, and a partial eye has been noted in radar imagery from Acapulco. Given this improved structure, the initial intensity has been set to 50 kt, leaning toward the latest Dvorak classification from SAB and the UW-CIMSS ADT estimate. Since Max has developed some inner-core structure, further strengthening seems likely, with the only apparent limiting factor being land interaction in 12 to 24 hours. The NHC forecast has been adjusted upward, and now shows Max reaching a 60-kt intensity in 12 h. Since some additional strengthening is possible before landfall, Max could become a hurricane before reaching the coast of Mexico. Quick weakening is forecast after landfall, and Max is expected to dissipate by 36 hours. The initial motion estimate is 065/03. Max should be steered east-northeastward to northeastward toward the coast by a mid-level ridge centered to the tropical cyclone's southeast. The new NHC track has been adjusted a little to the left of the previous one, toward the latest consensus aids. Given the new intensity forecast, a hurricane watch has been issued for a portion of the southwestern coast of Mexico. In addition to the increased wind threat, Max will produce life-threatening flooding rainfall in portions of the states of Guerrero and Oaxaca. FORECAST POSITIONS AND MAX WINDS INIT 14/0300Z 16.3N 101.1W 50 KT 60 MPH 12H 14/1200Z 16.7N 100.3W 60 KT 70 MPH 24H 15/0000Z 16.9N 99.3W 35 KT 40 MPH...INLAND 36H 15/1200Z...DISSIPATED $$ Forecaster Brennan

Tags: number discussion max storm

 

Tropical Depression Fifteen-E Forecast Discussion Number 10

2017-09-14 04:33:42| National Hurricane Center (East Pacific)

Issued at 800 PM PDT Wed Sep 13 2017 000 WTPZ45 KNHC 140233 TCDEP5 Tropical Depression Fifteen-E Discussion Number 10 NWS National Hurricane Center Miami FL EP152017 800 PM PDT Wed Sep 13 2017 During the afternoon hours, the mid-level center of the depression became completely removed from the now exposed low-level center. A small tight swirl embedded within a broader, elongated, low-level circulation is still evident, but deep convection is limited to a band displaced about 60 n mi to the west of the center. The initial intensity has been held at 30 kt, based on earlier ASCAT data. Given the poor convective structure of the depression, little change in intensity is expected for the next day or so. After that time, the GFS and ECMWF both forecast that the upper-level wind pattern will become more favorable for intensification. Once that happens, most of the intensity guidance forecasts that the cyclone will begin to steadily strengthen, especially after about 72 h. My forecast is a little higher than the previous NHC forecast at 96 h and 120 h, and is very close to IVCN. The depression has been nearly stationary for the past 6 hours. The initial motion estimate assumes at least some movement, and is a rather uncertain 270/02 kt. The global models agree that the cyclone will remain trapped in weak steering flow throughout the forecast period, but vary greatly on how much it will move. A complicating factor is that the GFS suggests that the low-level center may reform underneath the mid-level center to the south. My forecast assumes that the current center of circulation will persist, but a larger change may be required if such a reformation occurs. The new official track forecast is slower than the previous one for the first 36 h, but is close after that, and still shows little movement throughout the forecast period. The track forecast is based heavily on the ECMWF model, especially beyond day 2. FORECAST POSITIONS AND MAX WINDS INIT 14/0300Z 15.1N 121.3W 30 KT 35 MPH 12H 14/1200Z 15.2N 122.1W 30 KT 35 MPH 24H 15/0000Z 15.4N 123.1W 35 KT 40 MPH 36H 15/1200Z 15.5N 124.0W 35 KT 40 MPH 48H 16/0000Z 15.3N 124.8W 40 KT 45 MPH 72H 17/0000Z 15.5N 125.5W 45 KT 50 MPH 96H 18/0000Z 16.0N 125.5W 55 KT 65 MPH 120H 19/0000Z 16.5N 125.0W 50 KT 60 MPH $$ Forecaster Zelinsky

Tags: number discussion tropical depression

 

Tropical Depression Fifteen-E Forecast Discussion Number 9

2017-09-13 22:34:10| National Hurricane Center (East Pacific)

Issued at 200 PM PDT Wed Sep 13 2017 000 WTPZ45 KNHC 132033 TCDEP5 Tropical Depression Fifteen-E Discussion Number 9 NWS National Hurricane Center Miami FL EP152017 200 PM PDT Wed Sep 13 2017 The cloud pattern is still disorganized and the circulation appears to be somewhat elongated. Most of the deep convection is located to the southwest of the center due to some moderate northeasterly shear. Dvorak T-numbers have not changed and consequently, the initial intensity is kept at 30 kt. There are no obvious reasons why the cyclone will not intensify a little. The shear is forecast to decrease in a couple of days and the ocean is warm. On this basis, little change is anticipated during the next 12 hours or so and some slight strengthening is forecast thereafter, and the depression is still expected to become a tropical storm. The best estimate of the initial motion is toward the west or 275 degrees at 6 kt. The depression is embedded within light easterly flow south of a subtropical ridge. Global models indicate that the steering currents will weaken even more, and this flow will only produce a very slow westward motion through the next 3 days. After that time, the cyclone will probably begin to meander as the steering flow collapses completely. FORECAST POSITIONS AND MAX WINDS INIT 13/2100Z 15.1N 121.3W 30 KT 35 MPH 12H 14/0600Z 15.2N 122.2W 30 KT 35 MPH 24H 14/1800Z 15.4N 123.2W 35 KT 40 MPH 36H 15/0600Z 15.5N 124.0W 35 KT 40 MPH 48H 15/1800Z 15.5N 125.0W 40 KT 45 MPH 72H 16/1800Z 15.5N 125.5W 45 KT 50 MPH 96H 17/1800Z 15.5N 125.5W 45 KT 50 MPH 120H 18/1800Z 16.0N 125.0W 45 KT 50 MPH $$ Forecaster Avila

Tags: number discussion tropical depression

 

Sites : [677] [678] [679] [680] [681] [682] [683] [684] [685] [686] [687] [688] [689] [690] [691] [692] [693] [694] [695] [696] next »