HURRICANE ISAAC
|
09-13-2018, 03:07 PM
Post: #11
|
|||
|
|||
RE: HURRICANE ISAAC
No fishing in the gulf next week !!
|
|||
09-13-2018, 03:52 PM
Post: #12
|
|||
|
|||
RE: HURRICANE ISAAC
ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM Tropical Storm Isaac Discussion Number 25 NWS National Hurricane Center Miami FL AL092018 500 PM AST Thu Sep 13 2018 The center of Isaac has been mostly exposed during the past several hours as temporary bursts of convection fire just east of the center. Assuming some spin down of the circulation after the plane left, the initial wind speed is set to 35 kt. Since there haven't been any reports of sustained tropical-storm-force winds in the Lesser Antilles and the center is moving away, all watches and warning have been lowered. However, there remains a threat of flash flooding due to a large area of rain that has yet to move through the Lesser Antilles. Strong shear and mid-level dry air is forecast to persist for the next day or so, which should cause Isaac to drop back to tropical depression status on Friday. However, the shear is forecast to weaken by the weekend, and moisture values are expected to rise as the system gets deeper into the Caribbean Sea. These conditions would normally allow for some restregthening, but the initial character of the system is pretty weak, and it is uncertain whether there will be much left of Isaac to take advantage of the more conducive conditions. Model guidance has been inconsistent on the future of Isaac, which speaks to the lack of predictability of this situation. The bulk of the guidance show Isaac staying weak or degenerating into a tropical wave over the next few days, so the official forecast follows that consensus. At this point it is just best to keep an eye on the long-range forecast on each advisory to see if there are any changes. Isaac is moving westward at about 15 kt. A mid-level ridge is forecast to persist over the southwestern Atlantic, steering Isaac westward for the next few days, with a turn to the west-northwest possible at long range. The future track is very uncertain at long range because it is dependent on the intensity. If Isaac degenerates into a wave, the remnants will likely move south and west of the guidance mean, and if the cyclone is stronger, it will probably move slower and more to the right. The new NHC forecast assumes that Isaac will stay weak, and therefore is on the left and faster side of the guidance. FORECAST POSITIONS AND MAX WINDS INIT 13/2100Z 14.9N 63.2W 35 KT 40 MPH 12H 14/0600Z 14.9N 65.4W 35 KT 40 MPH 24H 14/1800Z 14.9N 68.2W 30 KT 35 MPH 36H 15/0600Z 14.9N 70.8W 30 KT 35 MPH 48H 15/1800Z 15.0N 73.0W 30 KT 35 MPH 72H 16/1800Z 16.2N 77.4W 30 KT 35 MPH 96H 17/1800Z 17.5N 81.5W 30 KT 35 MPH 120H 18/1800Z...DISSIPATED $$ Forecaster Blake Twitter updates we will follow you back http://twitter.com/Hardcoreweather Now on Facebook We will like you back http://www.facebook.com/pages/Hardcorewe...466?v=wall |
|||
09-14-2018, 07:27 AM
Post: #13
|
|||
|
|||
RE: HURRICANE ISAAC
207
WTNT44 KNHC 140832 TCDAT4 Tropical Depression Isaac Discussion Number 27 NWS National Hurricane Center Miami FL AL092018 500 AM AST Fri Sep 14 2018 Northwesterly shear continues to take a toll on Isaac. Although the system is still producing areas of deep convection, an ASCAT overpass that arrived shortly after the release of the previous advisory, indicated that the circulation had become even less defined. The ASCAT data also showed that the winds are below tropical storm strength, therefore the initial intensity has been reduced to 30 kt. Moderate to strong northwesterly shear and dry mid-level air are likely to cause additional weakening, and Isaac is forecast to degenerate into an open wave within the next several days, but this could occur much sooner if the current trends continue. When the system reaches the western Caribbean Sea the shear may relax somewhat and moisture levels are expected to be higher. These conditions could allow for regeneration of the system, but the ECMWF and GFS both show Issac weakening and moving over the western Caribbean as an open wave, and the NHC forecast follows this scenario. A low- to mid-level ridge over the southwestern Atlantic continues to steer Isaac westward, and this general motion should continue until dissipation occur. The new track forecast is once again essentially an update of the previous advisory. FORECAST POSITIONS AND MAX WINDS INIT 14/0900Z 15.0N 65.5W 30 KT 35 MPH 12H 14/1800Z 15.1N 67.3W 30 KT 35 MPH 24H 15/0600Z 15.2N 69.7W 30 KT 35 MPH 36H 15/1800Z 15.2N 72.0W 25 KT 30 MPH 48H 16/0600Z 15.4N 73.8W 25 KT 30 MPH 72H 17/0600Z 16.4N 77.7W 25 KT 30 MPH 96H 18/0600Z...DISSIPATED $$ Forecaster Brown Twitter updates we will follow you back http://twitter.com/Hardcoreweather Now on Facebook We will like you back http://www.facebook.com/pages/Hardcorewe...466?v=wall |
|||
09-15-2018, 07:50 AM
Post: #14
|
|||
|
|||
RE: HURRICANE ISAAC
559
WTNT44 KNHC 150841 TCDAT4 Remnants Of Isaac Discussion Number 31 NWS National Hurricane Center Miami FL AL092018 500 AM EDT Sat Sep 15 2018 A NOAA Hurricane Hunter aircraft investigated Isaac over the past few hours and was unable to identify a well-defined center. The plane found multiple small and poorly-defined circulations embedded within a larger area of weak and variable winds, well to the south of the previous estimated center location. The plane also found that the minimum pressure has risen to around 1006 mb. All of this data confirmed what two late-arriving ASCAT overpasses from earlier this evening indicated, that Isaac has opened up into a southwest to northeast oriented trough. Since Isaac does not have a well-defined center, it no longer meets the NHC definition of a tropical cyclone and this is the last advisory. The strongest SFMR winds found by the plane were around 30 kt, mainly to the north of the deep convection, so the intensity has been set at that value. Although some of the regional hurricane models suggest that small short-lived circulations like the ones found by the plane could temporarily spin up within the larger envelope of the tropical wave over the next several days, none of the dynamical models currently show any significant redevelopment of Isaac. The wave will likely continue westward across the Caribbean Sea over the next few days, producing gusty winds and occasional heavy rains over portions of Hispaniola and Jamaica. This is the last public advisory issued by the National Hurricane Center on Isaac. Additional information can be found in High Seas Forecasts issued by the National Weather Service, under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and available online at https://ocean.weather.gov/shtml/NFDHSFAT1.shtml. FORECAST POSITIONS AND MAX WINDS INIT 15/0900Z 14.8N 70.8W 30 KT 35 MPH 12H 15/1800Z...DISSIPATED $$ Forecaster Zelinsky Twitter updates we will follow you back http://twitter.com/Hardcoreweather Now on Facebook We will like you back http://www.facebook.com/pages/Hardcorewe...466?v=wall |
|||
« Next Oldest | Next Newest »
|
User(s) browsing this thread: 1 Guest(s)