Home discussion
 

Keywords :   


Tag: discussion

Tropical Storm ANA Forecast Discussion Number 7

2015-05-09 16:38:26| National Hurricane Center (Atlantic)

Issued at 1100 AM EDT SAT MAY 09 2015 000 WTNT41 KNHC 091438 TCDAT1 TROPICAL STORM ANA DISCUSSION NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012015 1100 AM EDT SAT MAY 09 2015 Deep convection has increased somewhat near the center of the storm, and SFMR observations from the Air Force Hurricane Hunters continue to support an intensity of 50 kt. Ana will be moving over the cooler waters to the northwest of the Gulf Stream later today, and water vapor imagery shows a belt of upper-level northerly flow advancing toward the tropical cyclone. The decreasing sea surface temperatures and increasing northerly shear should cause Ana to weaken as it nears the coast. The official intensity forecast is similar to that from the previous package, and very close to the latest intensity model consensus, IVCN. The initial motion estimate is 320/3. The track forecast reasoning remains basically unchanged from the past few advisories. Global models continue to predict that the blocking mid-level ridge to the north of Ana will shift eastward and weaken over the next couple of days. These models also show a broad trough moving from the central to the eastern U.S. over the next 72 hours or so. This should result in the cyclone turning northward and north-northeastward with a gradual increase in forward speed. The official track forecast is similar to the previous one and in good agreement with the latest dynamical model consensus, TVCN. FORECAST POSITIONS AND MAX WINDS INIT 09/1500Z 32.7N 77.9W 50 KT 60 MPH 12H 10/0000Z 33.2N 78.2W 45 KT 50 MPH 24H 10/1200Z 33.9N 78.7W 40 KT 45 MPH...INLAND 36H 11/0000Z 34.9N 78.5W 35 KT 40 MPH...INLAND 48H 11/1200Z 36.1N 77.4W 30 KT 35 MPH...INLAND 72H 12/1200Z 40.0N 72.0W 30 KT 35 MPH...POST-TROP/EXTRATROP 96H 13/1200Z...DISSIPATED $$ Forecaster Pasch

Tags: number discussion ana storm

 

California ARB posts discussion document for developing Advanced Clean Transit (ACT) regulation

2015-05-09 14:55:30| Green Car Congress

Tags: advanced posts document discussion

 
 

Tropical Storm ANA Forecast Discussion Number 6

2015-05-09 10:52:00| National Hurricane Center (Atlantic)

Issued at 500 AM EDT SAT MAY 09 2015 000 WTNT41 KNHC 090851 TCDAT1 TROPICAL STORM ANA DISCUSSION NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012015 500 AM EDT SAT MAY 09 2015 Satellite and NOAA Doppler radar data indicate that Ana has likely made the transition to a tropical cyclone based on the rapid decay of a previously persistent band of outer convection, recent development of inner-core convection within 30-40 nmi of the center, and weak anticyclonic outflow. Between 0500-0700 UTC, average Doppler velocities of 58-60 kt with isolated peak values of 63 kt were noted between 8,000-10,000 ft and within 30-40 dBZ echoes, which would correspond to about 53-54 kt surface winds. However, since that time, that outer band has weakened considerably, so the initial intensity will remain at 50 kt for this advisory. The initial motion estimate using a 12-hour motion is 340/03 kt. There is no significant change to the previous forecast track or reasoning. The global and regional models are in very good agreement that Tropical Storm Ana will move slowly toward the north-northwest or northwest for the next 36 hours or so, followed by a gradual turn toward the north and northeast ahead of an approaching deep-layer trough. By 72 hours, Ana is expected to become extratropical and be absorbed by a much larger extratropical low pressure system by 96 hours. The official track forecast is similar to the previous advisory and lies close to the multi-model consensus TVCN. The center and inner-core region of Ana currently lie along the axis of warmest Gulf Stream water of about 25C. Although inner-core convection has been developing during the past few hours, it is occurring in a region where the last recon flight only found winds of 30-40 kt at the surface and around 45 kt at flight-level. As a result, there could be some fluctuations in Ana's intensity in the near term this morning. By 12-24 hours, the cyclone's slow forward speed will take it over much cooler shelf waters. The combination of SSTs around 20C-22C and continued entrainment of mid-level dry air should induce at least slow weakening until landfall occurs. Although inland at 36 and 48 hours, the intensity has been held up slightly in anticipation of a band of stronger winds lying just offshore. The official intensity forecast is similar to the intensity consensus model ICON. FORECAST POSITIONS AND MAX WINDS INIT 09/0900Z 32.4N 77.6W 50 KT 60 MPH 12H 09/1800Z 32.8N 77.9W 45 KT 50 MPH 24H 10/0600Z 33.5N 78.4W 40 KT 45 MPH 36H 10/1800Z 34.3N 78.6W 35 KT 40 MPH...INLAND 48H 11/0600Z 35.2N 78.0W 30 KT 35 MPH...INLAND 72H 12/0600Z 39.0N 73.9W 30 KT 35 MPH...POST-TROP/EXTRATROP 96H 13/0600Z...ABSORBED BY LARGER EXTRATROPICAL LOW $$ Forecaster Stewart

Tags: number discussion ana storm

 

Subtropical Storm ANA Forecast Discussion Number 5

2015-05-09 05:41:52| National Hurricane Center (Atlantic)

Issued at 1100 PM EDT FRI MAY 08 2015 000 WTNT41 KNHC 090341 TCDAT1 SUBTROPICAL STORM ANA DISCUSSION NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012015 1100 PM EDT FRI MAY 08 2015 Data from an Air Force Reserve Unit Hurricane Hunter aircraft indicate that Ana has intensified. The strongest winds were measured in a band well to the east and northeast of the center. The current intensity is set at 50 kt, a little below the highest SFMR winds which are believed to be slightly rain-inflated. The satellite presentation of Ana is still somewhat subtropical, with almost all of the deep convection in a band over the northern semicircle of the circulation. Moreover, observations from the Hurricane Hunters indicate a radius of maximum winds of no less than 50-60 n mi. Therefore Ana is still being designated as a subtropical cyclone at this time. However, there is some indication that deep convection is beginning to develop nearer to the center, and this is a sign that the transition to a tropical cyclone may occur not long from now. Center fixes from the aircraft show a general northward drift of 350/2. There is little change to the track forecast reasoning from the previous package. Over the next few days, the presistent blocking ridge to the north of Ana is forecast to break down and shift eastward as a broad mid-tropospheric trough moves into the U.S. Ohio Valley region. This evolution of the steering flow should cause Ana to turn northwestward and then northward at a slightly faster forward speed before crossing the coast in 36 to 48 hours. Beyond that time, the flow ahead of the trough should carry Ana or its remnants northeastward at a substantially faster forward speed. The official track forecast is close to the previous one and also close to the latest multi-model consensus. Dynamical and statistical/dynamical intensity model guidance do not show much additional strengthening. In 24 hours or so, as Ana moves northwest of the Gulf Stream, it should encounter progressively cooler waters. This, along with the entrainment of drier air, should lead to weakening. The official wind speed forecast is fairly similar to the intensity model consensus. By 96 hours, the latest global model runs show the system degenerating into an open trough as Ana's post-tropical remnants merge with a large extratropical low over Atlantic Canada. FORECAST POSITIONS AND MAX WINDS INIT 09/0300Z 32.1N 77.4W 50 KT 60 MPH 12H 09/1200Z 32.4N 77.6W 50 KT 60 MPH 24H 10/0000Z 32.9N 78.1W 45 KT 50 MPH 36H 10/1200Z 33.6N 78.7W 40 KT 45 MPH 48H 11/0000Z 34.3N 78.6W 35 KT 40 MPH...INLAND 72H 12/0000Z 37.0N 76.0W 30 KT 35 MPH...POST-TROP/EXTRATROP 96H 13/0000Z...DISSIPATED $$ Forecaster Pasch

Tags: number discussion ana storm

 

Subtropical Storm ANA Forecast Discussion Number 5

2015-05-09 04:36:20| National Hurricane Center (Atlantic)

Issued at 1100 PM EDT FRI MAY 08 2015 000 WTNT41 KNHC 090236 TCDAT1 SUBTROPICAL STORM ANA DISCUSSION NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012015 1100 PM EDT FRI MAY 08 2015 Data from an Air Force Reserve Unit Hurricane Hunter aircraft indicate that Ana has intensified. The strongest winds were measured in a band well to the east and northeast of the center. The current intensity is set at 50 kt, a little below the highest SFMR winds which are believed to be slightly rain-inflated. The satellite presentation of Ana is still somewhat subtropical, with almost all of the deep convection in a band over the northern semicircle of the circulation. Moreover, observations from the Hurricane Hunters indicate a radius of maximum winds of no less than 50-60 n mi. Therefore Ana is still being designated as a subtropical cyclone at this time. However, there is some indication that deep convection is beginning to develop nearer to the center, and this is a sign that the transition to a tropical cyclone may occur not long from now. Center fixes from the aircraft show a general northward drift of 350/2. There is little change to the track forecast reasoning from the previous package. Over the next few days, the presistent blocking ridge to the north of Ana is forecast to break down and shift eastward as a broad mid-tropospheric trough moves into the U.S. Ohio Valley region. This evolution of the steering flow should cause Ana to turn northwestward and then northward at a slightly faster forward speed before crossing the coast in 36 to 48 hours. Beyond that time, the flow ahead of the trough should carry Ana or its remnants northeastward at a substantially faster forward speed. The official track forecast is close to the previous one and also close to the latest multi-model consensus. Dynamical and statistical/dynamical intensity model guidance do not show much additional strengthening. In 24 hours or so, as Ana moves northwest of the Gulf Stream, it should encounter progressively cooler waters. This, along with the entrainment of drier air, should lead to weakening. The official wind speed forecast is fairly similar to the intensity model consensus. By 96 hours, the latest global model runs show the system degenerating into an open trough as Ana's post-tropical remnants merge with a large extratopical low over Atlantic Canda. FORECAST POSITIONS AND MAX WINDS INIT 09/0300Z 32.1N 77.4W 50 KT 60 MPH 12H 09/1200Z 32.4N 77.6W 50 KT 60 MPH 24H 10/0000Z 32.9N 78.1W 45 KT 50 MPH 36H 10/1200Z 33.6N 78.7W 40 KT 45 MPH 48H 11/0000Z 34.3N 78.6W 35 KT 40 MPH...INLAND 72H 12/0000Z 37.0N 76.0W 30 KT 35 MPH...POST-TROP/EXTRATROP 96H 13/0000Z...DISSIPATED $$ Forecaster Pasch

Tags: number discussion ana storm

 

Sites : [1032] [1033] [1034] [1035] [1036] [1037] [1038] [1039] [1040] [1041] [1042] [1043] [1044] [1045] [1046] [1047] [1048] [1049] [1050] [1051] next »