Tropical Storm Arthur

Arthur Tropical Storm Track 1100 Hours May 19 2020
Arthur Tropical Storm Track 1100 Hours May 19 2020

Tropical Storm Arthur Radar 1100 Hours May 19 2020.jpgSpecial Tropical Weather Outlook – NWS National Hurricane Center Miami FL 1100 AM AST Tue May 19, 2020 (see Tuesday below)

Arthur has transitioned into an extratropical low this morning with a warm front extending northeastward from the circulation, any deep convection only along the front, and lots of more stable cumulus clouds near the center. Thus this is the last advisory. The initial intensity remains 50 kt based on continuity and model analyses. The main adjustments to the previous forecast include a quicker dissipation of the post-tropical cyclone, somewhat linked to the models showing a faster weakening after 12 hours, and a continuation of the westward shift in the track forecast in a day or two. These changes are consistent with the latest model consensus for track and similar to a GFS/ECMWF blend for intensity.

Dangerous coastal surf conditions and rip currents are expected to continue along portions of the mid-Atlantic and southeast U.S. coasts during the next couple of days. See products from your local National Weather Service Forecast Office for more details.

FORECAST POSITIONS AND MAX WINDS

INIT  19/1500Z 36.8N  68.6W   50 KT  60 MPH - Post Tropical (ESE Virginia Beach, VA)
 12H  20/0000Z 36.4N  66.9W   50 KT  60 MPH - Post Tropical (ESE Virginia Beach, VA)
 24H  20/1200Z 35.2N  65.6W   45 KT  50 MPH - Post Tropical (WNW St. Georges, Bermuda)
 36H  21/0000Z 33.6N  65.0W   40 KT  45 MPH - Post Tropical (WNW St. Georges, Bermuda)
 48H  21/1200Z 32.0N  64.5W   30 KT  35 MPH - Post Tropical (WSW St. Georges, Bermuda)
 60H  22/0000Z...DISSIPATED

Tropical Storm Arthur National Hurricane Center Miami FL 500 AM EDT Tue May 19, 2020 

Arthur’s cloud pattern has continued to take on a generally post-tropical appearance, though a recent convective burst near its center suggests that it isn’t quite post-tropical yet. Satellite imagery and earlier scatterometer data also indicate the presence of a developing warm front near the cyclone’s center, and this could be contributing to the development of the aforementioned convective burst. ASCAT-C data that arrived early this morning showed maximum winds of 45-50 kt, and this was the primary basis for the initial intensity.

Virtually no change was made to the intensity forecast. Despite the recent increase of convection near Arthur’s center, extratropical transition should finish fairly soon. Slight strengthening due to baroclinic forcing is possible through the afternoon, but the cyclone is forecast to begin spinning down by tonight or Wednesday morning. The global and regional models indicate that the system will dissipate within about 72 h, and this is reflected in the official forecast.

Only small adjustments were made to the track forecast, which remains near the multi-model consensus. As Arthur weakens it should be steered generally southward around the east side of a low-level ridge. The models differ on how quickly the southward turn will occur, but all agree on that general scenario. The latest NHC forecast is a little west of the previous one after 24 h.

Dangerous coastal surf conditions and rip currents are expected to continue along portions of the mid-Atlantic and southeast U.S. coasts during the next couple of days. See products from your local National Weather Service Forecast Office for more details.

FORECAST POSITIONS AND MAX WINDS

INIT  19/0900Z 37.0N  70.6W   50 KT  60 MPH - Tropical Storm (ENE Virginia Beach, VA)
 12H  19/1800Z 36.9N  68.7W   55 KT  65 MPH - Post Tropical (ENE Virginia Beach, VA)
 24H  20/0600Z 36.1N  66.7W   50 KT  60 MPH - Post Tropical (ENE Nags Head, NC)
 36H  20/1800Z 34.6N  65.7W   40 KT  45 MPH - Post Tropical (WNW St. Georges, Bermuda)
 48H  21/0600Z 33.3N  65.2W   35 KT  40 MPH - Post Tropical (WNW St. Georges, Bermuda)
 60H  21/1800Z 32.0N  65.0W   30 KT  35 MPH - Post Tropical (WSW St. Georges, Bermuda)
 72H  22/0600Z...DISSIPATED

Tropical Storm Arthur NWS National Hurricane Center Miami FL 1100 PM EDT Mon May 18, 2020 

Arthur’s cloud shield has shifted to the left or north side of the cyclone’s direction of motion since the previous advisory, which is a distinctive sign of a tropical cyclone beginning to lose its tropical characteristics, especially now due to the cyclone moving over 23 deg C sea-surface temperatures. However, there remains enough convection within 45-75 nmi of the center for Arthur to still be classified as a tropical cyclone. The initial intensity has been increased to 50 kt based on a recent 0129 UTC ASCAT-B overpass that indicated several 50-51 kt wind vectors existed in the northwestern quadrant.

The initial motion estimate is 070/13 kt. Arthur should move east- northeastward tonight and then turn toward the east by Tuesday morning as the cyclone moves around the northern periphery of a low- to mid-level ridge. On day 2, all of the global models are forecasting the mid- and upper-level circulations to separate from the low-level circulation, with the latter feature dropping southeastward and then southward around the eastern portion of a low-level ridge. The new track forecast is similar to but slightly east of the previous advisory track on days 2 and 3, and closely follows a blend of the consensus models TVCN and GFEX.

Only slight strengthening is expected during the next day or so due to baroclinic effects while Arthur undergoes extratropical transition. Data from NOAA Buoy 44014, located west Arthur’s center, indicate that a cold front passed over that station around 2300 UTC, which would place the front about 50-75 nmi west of the cyclone at this time. Therefore, a merger with the front is likely during the next 12 hours. The system should begin to steadily weaken shortly after 24 hours when Arthur will be moving over SSTs near 20 deg C, and in conjunction with the aforementioned decoupling of the circulations. Dangerous coastal surf conditions and rip currents are expected to continue along portions of the mid-Atlantic and southeast U.S. coasts during the next couple of days. See products from your local National Weather Service Forecast Office for more details.

FORECAST POSITIONS AND MAX WINDS

INIT  19/0300Z 36.4N  72.4W   50 KT  60 MPH - Tropical Storm (ENE Kill Devil Hills, NC)
 12H  19/1200Z 36.9N  70.1W   55 KT  65 MPH - Post Tropical (ESE Virginia Beach, VA)
 24H  20/0000Z 36.4N  67.3W   50 KT  60 MPH - Post Tropical (ESE Virginia Beach, VA)
 36H  20/1200Z 35.2N  65.8W   45 KT  50 MPH - Post Tropical (WNW St. Georges, Bermuda)
 48H  21/0000Z 33.7N  64.6W   40 KT  45 MPH - Post Tropical (ENE St. Georges, Bermuda)
 60H  21/1200Z 32.3N  64.4W   35 KT  40 MPH - Post Tropical (ESE St. Georges, Bermuda)
 72H  22/0000Z 30.9N  64.3W   25 KT  30 MPH - Post Tropical (ESE St. Georges, Bermuda)
 96H  23/0000Z...DISSIPATED

NWS National Hurricane Center Miami FL 500 PM EDT Mon May 18, 2020

Although the center of Arthur did not make landfall in the North Carolina Outer Banks, it passed within about 20 n mi southeast of Cape Hatteras around 1500 UTC. Tropical-storm-force wind gusts have been reported at several automated observing sites on and near the Outer Banks, with the highest sustained wind of 34 kt at Alligator River Bridge earlier this afternoon. Deep convection continues over the northeastern portion of Arthur’s circulation, but visible imagery has recently shown an increase in separation between low-level center and the convective activity. This is the result of increasing southwesterly shear and the beginning of the cyclone’s extratropical transition.

The initial intensity remains 45 kt, which was in agreement with the earlier aircraft data. As the cyclone completes its extratropical transition, some strengthening is forecast due to baroclinic processes. After 24 hours, little change in strength is expected until the frontal gradients decrease on Wednesday. The system should gradually spin down after that time, and dissipate by late in the week.

The initial motion estimate is 045/14 kt. Arthur should continue northeastward this evening, but is expected to turn eastward Tuesday morning as the cyclone becomes embedded within the mid-latitude westerlies. Troughing over the central and western Atlantic should cause the Arthur to turn southeastward on Wednesday when the steering flow becomes northwesterly. Little change was required to the previous NHC official forecast and the updated track again lies between the GFS, ECMWF, and the multi-model consensus.

Dangerous coastal surf conditions and rip currents are expected to continue along portions of the mid-Atlantic and southeast U.S. coasts during the next couple of days. See products from your local National Weather Service Forecast Office for more details.

FORECAST POSITIONS AND MAX WINDS

INIT  18/2100Z 36.1N  73.9W   45 KT  50 MPH - Tropical Storm (ENE Nags Head, NC)
 12H  19/0600Z 36.9N  71.6W   50 KT  60 MPH - Tropical Storm (ENE Virginia Beach, VA)
 24H  19/1800Z 37.0N  68.7W   50 KT  60 MPH - Post Tropical (ENE Virginia Beach, VA)
 36H  20/0600Z 36.2N  66.8W   50 KT  60 MPH - Post Tropical (WNW St. Georges, Bermuda)
 48H  20/1800Z 34.8N  65.5W   45 KT  50 MPH - Post Tropical (WNW St. Georges, Bermuda)
 60H  21/0600Z 33.0N  64.8W   40 KT  45 MPH - Post Tropical (WNW St. Georges, Bermuda)
 72H  21/1800Z 31.5N  64.8W   30 KT  35 MPH - Post Tropical (WSW St. Georges, Bermuda)
 96H  22/1800Z...DISSIPATED

NWS National Hurricane Center Miami FL 1100 AM EDT Mon May 18, 2020

Arthur has become a little better organized this morning with an overall increase in convection and banding noted since overnight. The first couple of reconnaissance aircraft passes through the center have shown that the pressure has fallen to around 996 mb. The plane has also reported several believable SFMR winds of 38-43 kt, and the anemometer on buoy 41025 at an elevation of only 4 m has reported a peak 1-minute wind of 37 kt. Based on these data the initial intensity is set at 45 kt.

The forward speed of Arthur has continued to increase and the estimated motion is north-northeast at 14 kt. The cyclone should turn northeastward later today and begin moving away from the North Carolina Outer Banks as a mid-latitude trough approaches from the west. By Tuesday, Arthur is forecast to turn eastward within the mid-latitude westerlies. After that time, a deepening trough over the central and western Atlantic is expected to cause the cyclone to turn southeastward as the steering flow turns northwestward. The GFS and ECMWF are now in relatively good agreement on this scenario and the new NHC track forecast lies between those typically reliable models and the multi-model consensus aids.

Although the vertical shear is increasing over the storm and it is soon moving over cooler waters, some strengthening due to baroclinic process is predicted over the next 24 hours. The storm should merge with a frontal boundary late tonight or early Tuesday which will complete Arthur’s transition to an extratropical cyclone. By Wednesday, the post-tropical cyclone should begin to weaken as the frontal gradients decrease. The post-tropical cyclone should dissipate in about 96 h.

Key Messages:

1. A Tropical Storm Warning is in effect for a portion of the North Carolina coast. Tropical-storm-force winds and heavy rains are expected there today.

2. Dangerous coastal surf conditions and rip currents are expected to spread northward along the southeast U.S. coast to the mid-Atlantic states during the next couple of days. See products from your local National Weather Service Forecast Office for more details.

FORECAST POSITIONS AND MAX WINDS

INIT  18/1500Z 35.1N  75.2W   45 KT  50 MPH - Tropical Storm (ESE Hatteras, NC)
 12H  19/0000Z 36.4N  73.3W   50 KT  60 MPH - Tropical Storm (ENE Kill Devil Hills, NC)
 24H  19/1200Z 37.2N  70.1W   50 KT  60 MPH - Post Tropical (ENE Virginia Beach, VA)
 36H  20/0000Z 36.8N  67.5W   50 KT  60 MPH - Post Tropical (ENE Virginia Beach, VA)
 48H  20/1200Z 35.5N  65.8W   50 KT  60 MPH - Post Tropical (WSW St. Georges, Bermuda)
 60H  21/0000Z 34.0N  65.0W   45 KT  50 MPH - Post Tropical (WSW St. Georges, Bermuda)
 72H  21/1200Z 32.0N  64.0W   30 KT  35 MPH - Post Tropical (ESE St. Georges, Bermuda)
 96H  22/1200Z...DISSIPATED

NWS National Hurricane Center Miami FL 800 AM EDT Mon May 18, 2020 

Arthur remains poorly organized in both satellite and radar imagery this morning, with the low-level center located near the southwestern edge of a complex of ragged convective bands. Surface observations from buoys off of the North Carolina coast suggest the central pressure has fallen a little since the last aircraft fix, so the intensity will be held at 40 kt for this advisory. The next aircraft is scheduled to reach Arthur between 11-12Z.

Arthur’s forward speed has increased with the initial motion now 020/12. A baroclinic trough and associated surface front approaching from the west should cause Arthur to turn northeastward during the next several hours, with the forecast track showing the center passing near or just offshore of the North Carolina Outer Banks. By Tuesday and Tuesday night, Arthur will be entering the strong mid-latitude Westerlies, which will steer cyclone eastward for a day or two. After that time, Arthur or its remnants should turn southeastward and southward on the southwest side of a deep-layer trough over the central Atlantic. The latest guidance is showing a more southward motion after 60 h than seen previously, and the new forecast track is also nudged southward during that time.

Arthur is moving near and almost parallel to the Gulf Stream, and the warm water could allow some strengthening before southwesterly shear increases significantly later today. The cyclone should merge with a frontal system and become extratropical in the 24-36 h period, with the global models indicating some increase in the winds north of the center as this occurs. The intensity forecast calls for Arthur to reach a 50 kt intensity in 36 h as an extratropical low in best agreement with the GFS model. After 48 h, the system should decay, and the global models suggest it should dissipate in the 96-120 h period. The new intensity forecast has only minor tweaks from the previous forecast.

Key Messages:

1. A Tropical Storm Warning is in effect for a portion of the North Carolina coast. Tropical-storm-force winds and heavy rains are expected there today.

2. Dangerous coastal surf conditions and rip currents are expected to spread northward along the southeast U.S. coast to the mid-Atlantic states during the next couple of days. See products from your local National Weather Service Forecast Office for more details.

FORECAST POSITIONS AND MAX WINDS

INIT  18/0900Z 33.5N  76.6W   40 KT  45 MPH - Tropical Storm (ESE Southport, NC)
 12H  18/1800Z 35.2N  74.9W   45 KT  50 MPH - Tropical Storm (ESE Buxton, NC)
 24H  19/0600Z 36.5N  72.1W   45 KT  50 MPH - Tropical Storm (ESE Virginia Beach, VA)
 36H  19/1800Z 36.5N  69.0W   50 KT  60 MPH - Post Tropical (ESE Virginia Beach, VA)
 48H  20/0600Z 35.6N  66.5W   50 KT  60 MPH - Post Tropical (ESE Virginia Beach, VA)
 60H  20/1800Z 34.4N  65.1W   45 KT  50 MPH - Post Tropical (WSW St. Georges, Bermuda)
 72H  21/0600Z 33.0N  64.5W   35 KT  40 MPH - Post Tropical (ESE St. Georges, Bermuda)
 96H  22/0600Z 31.0N  63.5W   25 KT  30 MPH - Post Tropical (ESE St. Georges, Bermuda)
120H  23/0600Z...DISSIPATED

NWS National Hurricane Center Miami FL 1100 PM EDT Sun May 17, 2020

Arthur’s appearance in radar and satellite imagery has degraded significantly since the previous advisory with very little convective banding features present now. However, an Air Force Reserve reconnaissance aircraft investigating the cyclone late this afternoon and early has found maximum 850-mb flight-level winds of 46 kt in the eastern quadrant along with reliable SFMR surface wind speeds of 36-38 kt, plus a central pressure of 1003 mb. Based on these data, the initial intensity has been held at 40 kt for this advisory since higher wind speeds could be present within areas of convection north of the center that were not sampled.

Aircraft and satellite fixes indicate that Arthur has continued to move north-northeastward or 020/09 kt. The cyclone is forecast to accelerate northeastward on Monday ahead of an approaching shortwave trough and frontal system, and remain just offshore of the North Carolina Outer Banks. By Tuesday night, Arthur will be entering the strong mid-latitude Westerlies, which will steer cyclone eastward and also induce extratropical transition when the cyclone merges with the aforementioned frontal system. The new NHC track guidance is tightly clustered about the previous forecast track, so no significant cross-track changes were required. However, some slight changes to the forward were required on days 2 and 3, and the new NHC track forecast now shows Arthur moving a little faster to the east and southeast on those days.

Arthur is currently moving over the warmest waters in the Gulfstream where ocean temperatures are 26-26.5 deg C. However, some mid-level shear undercutting the otherwise upper-level outflow pattern, coupled with the entrainment of dry mid-level air has disrupted the overall convective pattern. These unfavorable conditions should continue for the next couple of days, with only intermittent bursts of deep convection occurring near the center until Arthur passes northeast of the Outer Banks by late Monday. Thereafter, baroclinic effects along with extratropical transition are expected to cause some further strengthening before weakening begins late Tuesday and on Wednesday. The official intensity forecast follows a blend of the intensity consensus model IVCN, and the GFS and ECMWF model forecasts.

Key Messages:

1. A Tropical Storm Warning is in effect for a portion of the North Carolina coast. Tropical-storm-force winds and heavy rains are expected there on Monday.

2. Dangerous coastal surf conditions and rip currents are expected to spread northward along the southeast U.S. coast to the mid-Atlantic states during the next couple of days. See products from your local National Weather Service Forecast Office for more details.

FORECAST POSITIONS AND MAX WINDS

INIT  18/0300Z 32.4N  76.9W   40 KT  45 MPH - Tropical Storm (ESE Charleston, SC)
 12H  18/1200Z 34.0N  75.6W   40 KT  45 MPH - Tropical Storm (ESE Carolina Beach, NC)
 24H  19/0000Z 35.8N  73.2W   45 KT  50 MPH - Tropical Storm (ESE Nags Head, NC)
 36H  19/1200Z 36.4N  70.0W   50 KT  60 MPH - Post Tropical (ESE Virginia Beach, VA)
 48H  20/0000Z 36.0N  67.7W   50 KT  60 MPH - Post Tropical (ESE Virginia Beach, VA)
 60H  20/1200Z 35.0N  66.0W   45 KT  50 MPH - Post Tropical (ESE Virginia Beach, VA)
 72H  21/0000Z 33.8N  64.6W   40 KT  45 MPH - Post Tropical (ESE Virginia Beach, VA)
 96H  22/0000Z 31.6N  62.0W   30 KT  35 MPH - Post Tropical (ESE Virginia Beach, VA)
120H  23/0000Z...DISSIPATED

NWS National Hurricane Center Miami FL 500 PM EDT Sun May 17, 2020

Arthur’s satellite presentation has not changed much since the previous advisory. There are still some fragmented convective bands over the eastern portions of the circulation, but convective activity remains limited over the western half of the storm. A late-arriving ASCAT overpass from around the time of the previous advisory revealed somewhat lower wind speeds than reported by this morning’s reconnaissance aircraft. This could be the result of the convection becoming more fragmented after the aircraft sampled that portion of the storm or related to the low bias of the ASCAT instrument. Regardless, the initial intensity remains a possibly generous 40 kt for now. Another reconnaissance aircraft is scheduled to investigate Arthur this evening.Arthur Tropical Storm Force Wind Arrival

Arthur is forecast to remain within a low wind shear environment and over marginally warm sea surface temperatures through early Monday. These conditions favor some strengthening, however the sprawling structure of the cyclone and nearby dry mid-level air are likely to temper any increase in wind speed. After 36-48 hours, baroclinic forcing is expected to help the post-tropical cyclone maintain its intensity. Later in the period, the frontal gradients decrease which should cause weakening.

Recent satellite fixes show that the Arthur is still moving north-northeastward at about 8 kt. The tropical storm should begin to accelerate northeastward overnight as a mid-level trough moves into the eastern United States. By Tuesday night, the steering flow is expected to become westerly which should cause Arthur to turn eastward, then southeastward later in the forecast period. The lastest dynamical track guidance has come into a little better agreement through 36-48 hours with the GFS and ECMWF converging on the previous NHC track. As a result, little change was needed to the first couple of days of the earlier NHC track forecast. After that time, most of the guidance has trended toward a faster eastward and east-southeastward motion, and the NHC forecast has been adjusted accordingly in that direction as well.

Key Messages:

1. A Tropical Storm Warning is in effect for a portion of the North Carolina coast. Tropical-storm-force winds and heavy rains are expected there on Monday.

2. Dangerous coastal surf conditions and rip currents are expected to spread northward along the southeast U.S. coast to the mid-Atlantic states during the next couple of days. See products from your local National Weather Service Forecast Office for more details.

FORECAST POSITIONS AND MAX WINDS

INIT  17/2100Z 31.5N  77.2W   40 KT  45 MPH - Tropical Storm (ESE Savannah, GA)
 12H  18/0600Z 33.1N  76.4W   40 KT  45 MPH - Tropical Storm (ESE Myrtle Beach, SC)
 24H  18/1800Z 35.3N  74.6W   45 KT  50 MPH - Tropical Storm (ENE Buxton, NC)
 36H  19/0600Z 36.6N  71.9W   50 KT  60 MPH - Tropical Storm (ESE Virginia Beach, VA)
 48H  19/1800Z 36.8N  69.2W   50 KT  60 MPH - Post Tropical (ESE Virginia Beach, VA)
 60H  20/0600Z 36.3N  67.5W   50 KT  60 MPH - Post Tropical (ESE Virginia Beach, VA)
 72H  20/1800Z 35.6N  66.3W   45 KT  50 MPH - Post Tropical (ESE Virginia Beach, VA)
 96H  21/1800Z 34.0N  64.0W   35 KT  40 MPH - Post Tropical (ESE Virginia Beach, VA)
120H  22/1800Z...DISSIPATED

Tropical Storm Arthur NWS National Hurricane Center Miami FL 1100 AM EDT Sun May 17, 2020

Visible satellite imagery reveals a couple of convective bands over the eastern semicircle of the tropical storm, but convection is sparse over the western portion of the circulation. The latest reports from an Air Force reconnaissance aircraft show peak 925-mb flight-level winds of 48 kt, and believable SFMR winds of 35-40 kt. On this basis, the initial wind speed has been increased to 40 kt. The plane has reported a minimum pressure of 1002-1003 mb, which is down a few millibars from the previous flight.

Arthur has a little more than 24 hours in which to gradually strengthen. The storm will be traversing the relatively warm waters of the Gulf stream, and the vertical shear is forecast to remain low through early Monday. After that time, increasing shear and cooler sea surface temperatures should put a halt to the tropical cyclone strengthening processes. Baroclinic forcing is likely to help the post-tropical cyclone maintain its strengthen through an extratropical transition. Later in the forecast period, the global model guidance shows weakening as the frontal gradients decrease.Tropical Storm Arthur Tropical Force Winds

The storm is moving north-northeastward or 015/8 kt. Arthur is expected to begin moving a little faster later today and tonight as a mid-level trough approaches the eastern United States. Later in the forecast period, the cyclone should turn eastward within the westerly steering flow. Although the dynamical models are in agreement on the overall scenario, there remains some spread as to how close the center of Arthur will track to the North Carolina Outer Bands.

The GFS and HWRF remain along the western side of the guidance while the ECMWF and UKMET bracket the eastern side. The NHC track lies near the model consensus and little change was required to the previous track through 36-48 hours. After that time, the track guidance spread increases with the ECMWF showing a much faster east-southeastward motion than the GFS. The NHC forecast remains near the consensus after 48 hours, but there is less confidence in that portion of the track prediction.

Key Messages:

1. A Tropical Storm Warning is in effect for a portion of the North Carolina coast. Tropical-storm-force winds and heavy rains are expected there on Monday. 2. Dangerous coastal surf conditions and rip currents are expected to spread northward along the southeast U.S. coast to the mid-Atlantic states during the next couple of days.

FORECAST POSITIONS AND MAX WINDS

INIT  17/1500Z 30.5N  77.4W   40 KT  45 MPH - Tropical Storm (ENE Jacksonville,FL)
 12H  18/0000Z 32.0N  76.8W   45 KT  50 MPH - Tropical Storm (ESE Charleston, SC)
 24H  18/1200Z 34.3N  75.5W   50 KT  60 MPH - Tropical Storm (ESE Emerald Isle, NC)
 36H  19/0000Z 36.4N  73.2W   50 KT  60 MPH - Tropical Storm (ENE Kill Devil Hills. NC)
 48H  19/1200Z 37.3N  70.4W   50 KT  60 MPH - Post Tropical (ESE Ocean City, MD)
 60H  20/0000Z 37.1N  68.2W   50 KT  60 MPH - Post Tropical (ENE Virginia Beach, VA)
 72H  20/1200Z 36.5N  66.5W   45 KT  50 MPH - Post Tropical (ENE Virginia Beach, VA)
 96H  21/1200Z 35.5N  64.5W   35 KT  40 MPH - Post Tropical (ENE Virginia Beach, VA)
120H  22/1200Z...DISSIPATED

 

NWS National Hurricane Center Miami FL 715 PM EDT Sat May 16, 2020

For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Tropical Depression One, located over the western Atlantic Ocean off the east-central coast of Florida. Tropical cyclone formation is not expected during the next 5 days. Routine issuance of the Tropical Weather Outlook will resume on June 1, 2020. Until then, Special Tropical Weather Outlooks will be issued as conditions warrant.

NWS National Hurricane Center Miami FL 200 PM EDT Sat May 16, 2020

For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

Special Tropical Weather Outlook issued to discuss the potential for tropical or subtropical development off the east coast of Florida.

1. Data from the Air Force Hurricane Hunters and satellite images indicate that the low-pressure system located just off the coast of east-central Florida has become better defined today. In addition, the associated showers and thunderstorms continue to gradually organize. If these trends continues, advisories will likely be initiated on this system as a tropical or subtropical depression later today. Later in the weekend and early next week, the system is expected to move generally northeastward over the western Atlantic near or east of the Carolinas.

The system will continue to bring gusty winds and locally heavy rains across portions of east-central Florida through tonight. Interests near the North Carolina coast should closely monitor the progress of this system, as it could produce gusty winds and heavy rains there on Monday, and a tropical storm watch will likely be issued for that area later today.

In addition, hazardous marine conditions will spread northward during the next few days, likely causing dangerous surf and rip currents along much of the southeast and mid-Atlantic coasts of the U.S. See products from your local National Weather Service office for more details. Another Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate the system this evening. The next Special Tropical Weather Outlook on this system will be issued by 9 PM EDT today, or earlier if needed.

* Formation chance through 48 hours…high…near 100 percent. * Formation chance through 5 days…high…near 100 percent.

NWS National Hurricane Center Miami FL 800 PM EDT Thu May 14, 2020  

For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

Special Tropical Weather Outlook issued to discuss the potential for tropical or subtropical development near the northwest Bahamas. A trough of low pressure located over the Straits of Florida continues to produce disorganized shower activity and gusty winds across the Florida Keys, portions of extreme south Florida, and the northwestern Bahamas.

Gradual development of this system is expected, and it will likely become a tropical or subtropical storm by late Friday or Saturday when it is located near the northwestern Bahamas. Later in the weekend and early next week, the system is expected to move generally northeastward over the western Atlantic.

1. Regardless of development, the disturbance will continue to bring heavy rainfall to portions of the Florida Keys, southeast Florida and the Bahamas through Saturday. Tropical-storm-force wind gusts are also possible across portions of the Florida Keys, southeast Florida, and the Bahamas during the next day or two.

In addition, hazardous marine conditions are expected along the Florida east coast and in the Bahamas where Gale Warnings are in effect. See products from your local weather office and High Seas Forecasts for more details. An Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate this system tomorrow, if necessary. The next Special Tropical Weather Outlook on this system will be issued by 9 AM EDT Friday, or earlier, if necessary.

* Formation chance through 48 hours…high…70 percent. * Formation chance through 5 days…high…80 percent.

NWS National Hurricane Center Miami FL 800 PM EDT Thu May 14, 2020

For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

Special Tropical Weather Outlook issued to discuss the potential for tropical or subtropical development near the northwest Bahamas. A trough of low pressure located over the Straits of Florida continues to produce disorganized shower activity and gusty winds across the Florida Keys, portions of extreme south Florida, and the northwestern Bahamas. Gradual development of this system is expected, and it will likely become a tropical or subtropical storm by late Friday or Saturday when it is located near the northwestern Bahamas.

Later in the weekend and early next week, the system is expected to move generally northeastward over the western Atlantic. 1. Regardless of development, the disturbance will continue to bring heavy rainfall to portions of the Florida Keys, southeast Florida and the Bahamas through Saturday. Tropical-storm-force wind gusts are also possible across portions of the Florida Keys, southeast Florida, and the Bahamas during the next day or two.

In addition, hazardous marine conditions are expected along the Florida east coast and in the Bahamas where Gale Warnings are in effect. See products from your local weather office and High Seas Forecasts for more details. An Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate this system tomorrow, if necessary. The next Special Tropical Weather Outlook on this system will be issued by 9 AM EDT Friday, or earlier, if necessary.

* Formation chance through 48 hours…high…70 percent. * Formation chance through 5 days…high…80 percent.

NWS National Hurricane Center Miami FL 240 PM EDT Thu May 14, 2020 

For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

Special Tropical Weather Outlook issued to discuss the potential for tropical or subtropical development near the northwest Bahamas.

A trough of low pressure over the Straits of Florida is producing a large area of cloudiness and thunderstorms. Environmental conditions are expected to become conducive for development, and this system is likely to become a tropical or subtropical storm by late Friday or Saturday when it is located near the northwestern Bahamas.

The system is then forecast to move generally northeastward over the western Atlantic early next week. Regardless of development, the disturbance has the potential to bring heavy rainfall to portions of the Florida Keys, southeast Florida, and the Bahamas through Saturday. Tropical-storm-force wind gusts are also possible in the Florida Keys, southeast Florida, and the Bahamas during the next day or two. Hazardous marine conditions are also expected along the Florida east coast and in the Bahamas where Gale Warnings are in effect.

See products from your local weather office and High Seas Forecasts for more details. An Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate this system tomorrow, if necessary. The next Special Tropical Weather Outlook on this system will be issued by 9 PM EDT today, or earlier, if necessary.

* Formation chance through 48 hours…high…70 percent. * Formation chance through 5 days…high…80 percent.

NWS National Hurricane Center Miami FL 725 PM EDT Wed May 13, 2020

For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

Special Tropical Weather Outlook issued to discuss the potential for subtropical development this weekend northeast of the Bahamas.

A broad area of low pressure is expected to develop in a couple of days near or just north of the Bahamas. Environmental conditions appear conducive for the gradual development of this system, and a subtropical depression or storm is likely to form this weekend. The system is expected to move generally northeastward over the western Atlantic through early next week. The next Special Tropical Weather Outlook on this system will be issued by 9 AM EDT Thursday, or earlier, if necessary.

* Formation chance through 48 hours…low…10 percent. * Formation chance through 5 days…high…70 percent.

Tropical Weather Outlook NWS National Hurricane Center Miami FL 800 AM EDT Wed May 13, 2020

Corrected to remove double labels For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

Special Tropical Weather Outlook issued to discuss the potential for subtropical development this weekend northeast of the Bahamas.

1. A broad area of low pressure is expected to develop late this week or early this weekend near or within a couple of hundred miles north of the Bahamas. Environmental conditions appear conducive for the gradual development of this system, and a subtropical depression or storm is likely to form this weekend while it moves northeastward over the western Atlantic. The next Special Tropical Weather Outlook on this system will be issued by 9 PM EDT Wednesday, or earlier, if necessary.

* Formation chance through 48 hours…low…near 0 percent. * Formation chance through 5 days…high...70 percent.

NWS National Hurricane Center Miami FL 730 PM EDT Tue May 12, 2020 

For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

Special Tropical Weather Outlook issued to discuss the potential for subtropical development this weekend northeast of the Bahamas.

1. A broad area of low pressure is expected to develop late this week or early this weekend a couple of hundred miles north of the Bahamas. Environmental conditions appear conducive for gradual development of this system, and a subtropical depression or storm is likely to form this weekend while it moves northeastward over the western Atlantic.

The next Special Tropical Weather Outlook on this system will be issued by 9 AM EDT Wednesday, or earlier, if necessary.

* Formation chance through 48 hours…low…near 0 percent. * Formation chance through 5 days…high…70 percent.

NWS National Hurricane Center Miami FL 1005 AM EDT Tue May 12, 2020

For the North Atlantic, The Caribbean Sea and the Gulf of Mexico:

Special Tropical Weather Outlook issued to discuss the potential for subtropical development this weekend northeast of the Bahamas.

1. An area of low pressure is expected to develop this weekend,   a couple of hundred miles northeast of the Bahamas. Environmental conditions appear conducive for this system to acquire some subtropical characteristics as it moves northeastward through Sunday.

The next Special Tropical Weather Outlook on this system will be issued by 9 PM EDT Tuesday, or earlier, if necessary.

* Formation chance through 48 hours…low…near 0 percent. * Formation chance through 5 days…medium…50 percent.

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Video:National Weather Discussion Plus a look at Post Tropical Storm Arthur