Home › discussion
 

Keywords :   


Tag: discussion

Hurricane NICOLE Forecast Discussion Number 35

2016-10-12 22:33:35| National Hurricane Center (Atlantic)

Issued at 500 PM AST WED OCT 12 2016 000 WTNT45 KNHC 122033 TCDAT5 HURRICANE NICOLE DISCUSSION NUMBER 35 NWS NATIONAL HURRICANE CENTER MIAMI FL AL152016 500 PM AST WED OCT 12 2016 Nicole has a very impressive satellite presentation this afternoon. The eye has warmed and become more distinct since this morning, and the convective cloud tops surrounding the eye have cooled. As a result, subjective Dvorak intensity estimates have increased to T5.5/102 kt from TAFB and SAB. Since earlier satellite estimates were slightly higher than the intensity supported by this morning's reconnaissance data, the initial intensity has been raised to 95 kt, which is slightly lower than current Dvorak estimates. Another Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate Nicole this evening and should provide a better assessment of the hurricane's intensity. Low vertical wind shear and warm waters along the path of the hurricane through tonight could allow for some additional strengthening, and Nicole is forecast to reach major hurricane strength before it passes Bermuda. After that time, increasing southwesterly shear and cooler waters should cause some weakening. Strong westerly shear in a couple of days is expected to cause Nicole to become post-tropical, but baroclinic forcing is expected to keep the cyclone very strong through the entire forecast period. There is a large amount of uncertainty in the global models as to how much in the way of tropical characteristics Nicole will have late in the period, and the status of the cyclone is of low confidence at that time. Nicole is moving just east of due north or 010/9 kt. The hurricane will be moving into the mid-latitude southwesterly flow, which will cause Nicole to accelerate north-northeastward and then northeastward during the next 24 hours. This motion will bring the core of the hurricane near or over Bermuda on Thursday. In about 72 hours a shortwave trough is forecast to bypass the cyclone, which should cause Nicole to slow down and meander over the North Atlantic at days 4 and 5. FORECAST POSITIONS AND MAX WINDS INIT 12/2100Z 29.2N 66.6W 95 KT 110 MPH 12H 13/0600Z 30.5N 66.1W 100 KT 115 MPH 24H 13/1800Z 32.7N 64.3W 95 KT 110 MPH 36H 14/0600Z 34.6N 61.4W 85 KT 100 MPH 48H 14/1800Z 36.6N 57.5W 80 KT 90 MPH 72H 15/1800Z 38.8N 51.5W 75 KT 85 MPH...POST-TROPICAL 96H 16/1800Z 38.8N 50.0W 65 KT 75 MPH...POST-TROPICAL 120H 17/1800Z 40.0N 49.5W 65 KT 75 MPH...POST-TROPICAL $$ Forecaster Brown

Tags: number discussion nicole forecast

 

Hurricane NICOLE Forecast Discussion Number 34

2016-10-12 16:45:06| National Hurricane Center (Atlantic)

Issued at 1100 AM AST WED OCT 12 2016 000 WTNT45 KNHC 121444 TCDAT5 HURRICANE NICOLE DISCUSSION NUMBER 34 NWS NATIONAL HURRICANE CENTER MIAMI FL AL152016 1100 AM AST WED OCT 12 2016 The satellite presentation of the hurricane has changed very little during the past 6 to 12 hours. Nicole remains a very symmetric hurricane with a distinct 30 nmi wide eye. An Air Force Reserve Hurricane Hunter aircraft flew one alpha pattern through the storm this morning and recorded peak 700-mb flight-level winds of 91 kt, SFMR winds of 79 kt, and a minimum pressure of 969 mb. Since the aircraft only sampled a small portion of the circulation, the initial intensity is set 85 kt, which is a blend of the aircraft data and the most recent subjective Dvorak satellite estimates. The aircraft data indicate that Nicole has grown in size since yesterday, and the initial and forecast wind radii have been adjusted accordingly. Environmental conditions are forecast to be conducive for some strengthening while Nicole approaches Bermuda during the next day or so. After that time, increasing southwesterly shear and cooler sea surface temperatures are expected to induce weakening. Nicole is forecast to interact with a frontal boundary in about 72 hours, but it is not clear as to whether Nicole will complete its transformation into an extratropical low by days 4 and 5. For now, the NHC forecast maintains persistence with the previous advisories and predicts Nicole to lose tropical characteristics by 96 h but remain an intense storm system over the north Atlantic. The aircraft and satellite fixes indicate that the hurricane has turned northward, and Nicole should stay on this heading with some increase in forward speed today. The hurricane will become embedded within the mid-latitude flow on Thursday, which should steer Nicole northeastward with an additional increase in forward speed. The NHC forecast is once again very close to the previous advisory, and shows the core of Nicole passing near or over Bermuda between 24 and 36 hours. Later in the period, the cyclone is forecast to slow down and meander over the north Atlantic as it interacts with a large cut-off low well to the southeast of Atlantic Canada. FORECAST POSITIONS AND MAX WINDS INIT 12/1500Z 28.4N 66.9W 85 KT 100 MPH 12H 13/0000Z 29.5N 66.6W 90 KT 105 MPH 24H 13/1200Z 31.5N 65.4W 90 KT 105 MPH 36H 14/0000Z 33.7N 63.1W 85 KT 100 MPH 48H 14/1200Z 35.8N 59.7W 80 KT 90 MPH 72H 15/1200Z 39.1N 53.0W 75 KT 85 MPH 96H 16/1200Z 39.2N 50.5W 65 KT 75 MPH...POST-TROPICAL 120H 17/1200Z 39.2N 50.0W 65 KT 75 MPH...POST-TROPICAL $$ Forecaster Brown

Tags: number discussion nicole forecast

 
 

Hurricane NICOLE Forecast Discussion Number 33

2016-10-12 10:37:04| National Hurricane Center (Atlantic)

Issued at 500 AM AST WED OCT 12 2016 000 WTNT45 KNHC 120836 TCDAT5 HURRICANE NICOLE DISCUSSION NUMBER 33 NWS NATIONAL HURRICANE CENTER MIAMI FL AL152016 500 AM AST WED OCT 12 2016 Nicole's cloud pattern on satellite continues to be very impressive with a large eye surrounded by deep convection and a good upper- level outflow in all quadrants. T-numbers from TAFB and SAB remain 4.5/77 kt, but objective numbers from UW-CIMMS are up to 5.7 on the Dvorak scale. The initial intensity is then set to 85 kt, based on a blend of these estimates. An Air Force plane will be in the eye of Nicole around 1200 UTC this morning, and will provide an intensity update. Environmental conditions are conducive for some additional strengthening in the next day or so, and Nicole is forecast to be at its peak in intensity while it moves near Bermuda. After 36 hours, the shear is forecast to increase significantly resulting in some weakening. Nicole should then become a post-tropical cyclone by 96 hours. Most of the global models indicate that the post-tropical cyclone will maintain winds of near hurricane strength, and so does the NHC forecast. Satellite fixes indicate that Nicole is moving toward the north- northwest or 340 degrees at 6 kt. The steering pattern has not changed, and in the next 12 hours or so, the hurricane will become embedded in the mid-latitude southwesterly flow. This pattern should force Nicole to turn to the north-northeast and then east with a gradual increase in forward speed. The NHC forecast track is very similar to the previous one primarily during the next 24 to 36 hours, bringing the core of Nicole very near or over Bermuda. The forecast track is in the middle of the guidance envelope and is basically on top of the multi-model consensus TVCN. FORECAST POSITIONS AND MAX WINDS INIT 12/0900Z 27.9N 67.0W 85 KT 100 MPH 12H 12/1800Z 28.9N 67.1W 90 KT 105 MPH 24H 13/0600Z 30.6N 66.4W 90 KT 105 MPH 36H 13/1800Z 32.6N 64.6W 90 KT 105 MPH 48H 14/0600Z 35.0N 61.8W 80 KT 90 MPH 72H 15/0600Z 39.0N 55.0W 75 KT 85 MPH 96H 16/0600Z 40.0N 51.0W 70 KT 80 MPH...POST-TROPICAL 120H 17/0600Z 40.0N 50.5W 65 KT 75 MPH...POST-TROPICAL $$ Forecaster Avila

Tags: number discussion nicole forecast

 

Hurricane NICOLE Forecast Discussion Number 32

2016-10-12 04:36:58| National Hurricane Center (Atlantic)

Issued at 1100 PM AST TUE OCT 11 2016 000 WTNT45 KNHC 120236 TCDAT5 HURRICANE NICOLE DISCUSSION NUMBER 32 NWS NATIONAL HURRICANE CENTER MIAMI FL AL152016 1100 PM AST TUE OCT 11 2016 Nicole's cloud pattern was quite impressive after the release of the previous advisory, with a distinct eye surrounded by a ring of cloud tops of around -70C. However, by 00Z the eye was no longer apparent in geostationary imagery, and the Dvorak classifications from TAFB and SAB were T4.5/77 kt. The eye has reappeared recently, but the convective tops are a bit more ragged. The initial intensity is set to 80 kt, between the subjective Dvorak estimates and the latest UW-CIMSS ADT of around 90 kt. Environmental conditions appear conducive for some additional strengthening in the next 24 hours or so, with the cyclone over 28-29C waters and the shear 15 kt or less. The NHC intensity forecast is similar to the previous one during this time and is above the consensus. The SHIPS model shows southwesterly shear increasing to 45-50 kt by 48 hours, which should result in some weakening. Nicole will interact with an upper-level trough in 3-4 days, but global model fields and the FSU phase space diagrams suggest that Nicole won't complete extratropical transition when it is left behind by the progressive trough by day 5. Therefore, the NHC forecast shows Nicole as post-tropical at days 4 and 5, but baroclinic forcing is expected to keep cyclone near hurricane intensity through the end of the forecast period. Nicole has moved little during the past few hours, as the cyclone is caught in a region of weak steering currents. In fact, a slow looping motion has been noted since the previous advisory, and the best estimate of the initial motion is a westward drift at around 2 kt. The synoptic reasoning has not changed, as Nicole is expected to gradually recurve into the mid-latitude westerlies in the next 48 hours and then turn east-northeastward ahead of an upper-level trough moving off the U.S. east coast. By the end of the period, the trough leaves Nicole behind to the south of a ridge centered over the Davis Strait, which should result in a slow southeastward drift at day 5. The NHC track has been shifted a little to the right of the previous one and is a little slower during the first 36-48 hours, bringing Nicole near or over Bermuda. Late in the period, a larger rightward shift was made to the NHC track. The new official forecast remains near the middle of the guidance envelope and is close to the latest multi-model consensus aid TVCN. FORECAST POSITIONS AND MAX WINDS INIT 12/0300Z 27.3N 66.6W 80 KT 90 MPH 12H 12/1200Z 28.2N 66.9W 85 KT 100 MPH 24H 13/0000Z 29.6N 66.8W 90 KT 105 MPH 36H 13/1200Z 31.5N 65.7W 90 KT 105 MPH 48H 14/0000Z 33.9N 63.3W 85 KT 100 MPH 72H 15/0000Z 38.5N 56.5W 80 KT 90 MPH 96H 16/0000Z 40.5N 52.0W 70 KT 80 MPH...POST-TROPICAL 120H 17/0000Z 40.0N 51.5W 65 KT 75 MPH...POST-TROPICAL $$ Forecaster Brennan

Tags: number discussion nicole forecast

 

Hurricane NICOLE Forecast Discussion Number 31

2016-10-11 22:38:00| National Hurricane Center (Atlantic)

Issued at 500 PM AST TUE OCT 11 2016 000 WTNT45 KNHC 112037 TCDAT5 HURRICANE NICOLE DISCUSSION NUMBER 31 NWS NATIONAL HURRICANE CENTER MIAMI FL AL152016 500 PM AST TUE OCT 11 2016 Nicole has continued to strengthen today with the cloud pattern becoming much better organized since this morning. A 20 to 25 n mi wide eye has developed and become better defined within a rather symmetric central dense overcast. An Air Force Reserve Hurricane Hunter aircraft that investigated Nicole this afternoon has measured peak 850-mb flight-level winds of 79 kt, SFMR winds of around 65 kt, and a minimum pressure of 980 mb. Based on these data, and the continued increase in organization the initial wind speed has been increased to 70 kt. Environmental conditions consisting of low vertical wind shear and warm sea surface temperatures along the track of Nicole should allow for additional intensification during the next day or so. In fact, the SHIPS Rapid Intensification Index shows nearly a 30 percent chance of a 30 kt increase in wind speed during the next 24 hours. The NHC intensity forecast has been increased from the previous advisory and calls for Nicole to be near major hurricane strength when it passes near Bermuda in 36 to 48 hours. The NHC forecast calls for a faster increase in strength during the next 24 hours, but is close to the peak shown by the LGEM and FSSE models. Later in the forecast period increasing shear and cooler SSTs should result in some weakening, but the global models predict that Nicole will become a large and powerful extratropical low over the North Atlantic in 3 to 4 days. Satellite and aircraft fixes indicate that Nicole is moving northwestward at about 4 kt. The track forecast reasoning remains unchanged from the previous advisory. Nicole should turn northward into a break in the subtropical ridge by Wednesday and then turn northeastward as it reaches the mid-latitude westerlies. The dynamical models remain in good agreement, and the updated NHC forecast is again near the middle of the guidance envelope. The new official forecast is also very similar to the previous track. FORECAST POSITIONS AND MAX WINDS INIT 11/2100Z 27.4N 66.4W 70 KT 80 MPH 12H 12/0600Z 28.0N 66.9W 85 KT 100 MPH 24H 12/1800Z 29.1N 67.1W 90 KT 105 MPH 36H 13/0600Z 30.8N 66.5W 95 KT 110 MPH 48H 13/1800Z 33.1N 64.9W 95 KT 110 MPH 72H 14/1800Z 38.0N 59.0W 85 KT 100 MPH 96H 15/1800Z 41.0N 54.0W 75 KT 85 MPH...POST-TROP/EXTRATROP 120H 16/1800Z 41.5N 53.0W 65 KT 75 MPH...POST-TROP/EXTRATROP $$ Forecaster Brown

Tags: number discussion nicole forecast

 

Sites : [781] [782] [783] [784] [785] [786] [787] [788] [789] [790] [791] [792] [793] [794] [795] [796] [797] [798] [799] [800] next »