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Coastal Watches/Warnings and Forecast Cone for Storm Center

* If the storm is forecast to dissipate within 3 days, the “Full Forecast” and “3 day” graphic will be identical

Click Here for a 5-day Cone Printer Friendly Graphic

How to use the cone graphic (video):

About this product:

NHC tropical cyclone forecast tracks can be in error. This forecast uncertainty is conveyed by the track forecast “cone”, the solid white and stippled white areas in the graphic. The solid white area depicts the track forecast uncertainty for days 1-3 of the forecast, while the stippled area depicts the uncertainty on days 4-5. Historical data indicate that the entire 5-day path of the center of the tropical cyclone will remain within the cone about 60-70% of the time. To form the cone, a set of imaginary circles are placed along the forecast track at the 12, 24, 36, 48, 72, 96, and 120 h positions, where the size of each circle is set so that it encloses 67% of the previous five years official forecast errors. The cone is then formed by smoothly connecting the area swept out by the set of circles.

It is also important to realize that a tropical cyclone is not a point. Their effects can span many hundreds of miles from the center. The area experiencing hurricane force (one-minute average wind speeds of at least 74 mph) and tropical storm force (one-minute average wind speeds of 39-73 mph) winds can extend well beyond the white areas shown enclosing the most likely track area of the center. The distribution of hurricane and tropical storm force winds in this tropical cyclone can be seen in the Wind History graphic linked above.

Considering the combined forecast uncertainties in track, intensity, and size, the chances that any particular location will experience winds of 34 kt (tropical storm force), 50 kt, or 64 kt (hurricane force) from this tropical cyclone are presented in tabular form for selected locations and forecast positions. This information is also presented in graphical form for the 34 kt, 50 kt, and 64 kt thresholds.

Note:  A detailed definition of the NHC track forecast cone is also available.

  000 WTNT41 KNHC 020840 TCDAT1  Tropical Storm Wanda Discussion Number  10 NWS National Hurricane Center Miami FL       AL212021 900 AM GMT Tue Nov 02 2021  Wanda has become a little better organized since yesterday evening with convection, albeit not very deep, now wrapping around the  center of the storm.  Apparently the vertical shear over the  cyclone has relaxed somewhat, and the center is now more embedded  within the convection.  This implies that some strengthening has  occurred and the intensity estimate is increased to 45 kt for this  advisory.  This is also in agreement with a subjective Dvorak  satellite estimate from SAB.  Interestingly, satellite-derived SST  analyses indicate that Wanda is currently located over a small patch  of warmer ocean waters, near 25 deg C.  The storm is moving a little faster toward the east-northeast, or  at about 060/7 kt.  During the next couple of days, Wanda is likely  to remain embedded within a mid-tropospheric trough .  A turn  toward the north is expected during the next 48 to 60 hours  while the system moves along the eastern portion of the  trough. Later in the forecast period, a ridge building to the west  and northwest of Wanda should force a turn toward the east and  east-southeast.  The official forecast has been shifted to the  right of the previous NHC track at days 4 and 5, following the  latest dynamical model consensus.  It should be noted that the GFS  model shows a track significantly farther south at this later time  frame.  Although Wanda will soon be moving over cooler waters, the SHIPS,  LGEM, and HCCA intensity guidance indicate that the system will  strengthen a little more in the short term, and then more or less  maintain its intensity for the next 48 hours or so.  This is  probably due to fairly low vertical shear and relatively cool  upper-tropospheric temperatures during this time.  Later, gradual  weakening is likely, due to increased shear and cool waters.  However baroclinic effects could at least partially offset the  weakening process.  The official intensity forecast is in good  agreement with the corrected model consensus, HCCA, solution.   Around 72 hours, simulated satellite imagery shows a loss of  tropical cyclone-like cloud structure so the NHC forecast indicates  a post-tropical phase by that time.   FORECAST POSITIONS AND MAX WINDS  INIT  02/0900Z 35.0N  40.9W   45 KT  50 MPH  12H  02/1800Z 36.1N  40.3W   50 KT  60 MPH  24H  03/0600Z 37.8N  39.9W   50 KT  60 MPH  36H  03/1800Z 39.8N  39.7W   50 KT  60 MPH  48H  04/0600Z 41.6N  39.5W   50 KT  60 MPH  60H  04/1800Z 42.6N  39.0W   45 KT  50 MPH  72H  05/0600Z 43.0N  37.1W   45 KT  50 MPH...POST-TROPICAL  96H  06/0600Z 41.8N  33.1W   45 KT  50 MPH...POST-TROPICAL 120H  07/0600Z 41.0N  29.4W   40 KT  45 MPH...POST-TROPICAL  $$ Forecaster Pasch  

Coastal Watches/Warnings and Forecast Cone for Storm Center

* If the storm is forecast to dissipate within 3 days, the “Full Forecast” and “3 day” graphic will be identical

Click Here for a 5-day Cone Printer Friendly Graphic

How to use the cone graphic (video):

About this product:

NHC tropical cyclone forecast tracks can be in error. This forecast uncertainty is conveyed by the track forecast “cone”, the solid white and stippled white areas in the graphic. The solid white area depicts the track forecast uncertainty for days 1-3 of the forecast, while the stippled area depicts the uncertainty on days 4-5. Historical data indicate that the entire 5-day path of the center of the tropical cyclone will remain within the cone about 60-70% of the time. To form the cone, a set of imaginary circles are placed along the forecast track at the 12, 24, 36, 48, 72, 96, and 120 h positions, where the size of each circle is set so that it encloses 67% of the previous five years official forecast errors. The cone is then formed by smoothly connecting the area swept out by the set of circles.

It is also important to realize that a tropical cyclone is not a point. Their effects can span many hundreds of miles from the center. The area experiencing hurricane force (one-minute average wind speeds of at least 74 mph) and tropical storm force (one-minute average wind speeds of 39-73 mph) winds can extend well beyond the white areas shown enclosing the most likely track area of the center. The distribution of hurricane and tropical storm force winds in this tropical cyclone can be seen in the Wind History graphic linked above.

Considering the combined forecast uncertainties in track, intensity, and size, the chances that any particular location will experience winds of 34 kt (tropical storm force), 50 kt, or 64 kt (hurricane force) from this tropical cyclone are presented in tabular form for selected locations and forecast positions. This information is also presented in graphical form for the 34 kt, 50 kt, and 64 kt thresholds.

Note:  A detailed definition of the NHC track forecast cone is also available.

  000 WTNT41 KNHC 020239 TCDAT1  Tropical Storm Wanda Discussion Number   9 NWS National Hurricane Center Miami FL       AL212021 300 AM GMT Tue Nov 02 2021  The satellite presentation of Wanda indicates the system is  struggling with the effects of dry air and vertical wind shear  tonight. The center of the cyclone is partially exposed, with dry  mid-level air wrapping around the western and southern portions of  its circulation. The moderate to deep convection associated with  Wanda is displaced to the east and northeast of its center. A  partial ASCAT-B pass shows tropical-storm-force winds are occurring  in the southwestern quadrant of the storm. The latest objective and  subjective satellite estimates range from 35-40 kt, and the initial  intensity is held at 40 kt for this advisory.  Wanda is moving east-northeastward, or 75/6 kt. The complex steering pattern over the northern Atlantic during the next several days makes for a challenging track forecast. In the near term, Wanda is expected to turn toward the northeast and north on Tuesday and Wednesday as the cyclone is steered by a mid- to upper-level trough over the north-central Atlantic. The track models are well clustered for the first couple days of the forecast period, but then significant differences emerge in the guidance at days 3-5. The new GFS deviates from its previous run and shows the cyclone accelerating eastward to northeastward as it eventually merges with an approaching baroclinic system late this week. Meanwhile, the ECMWF shows a narrow ridge building to the north and west of Wanda, which slows its forward motion and eventually turns the cyclone southward. The other global models generally lie somewhere in between the divergent GFS/ECMWF solutions. Given the above average uncertainty and lack of run-to-run model continuity, the NHC official track forecast remains near or between the HCCA and TVCA consensus aids.  Overall, little change in strength is expected during the next several days. While the deep-layer shear is expected to diminish through midweek, Wanda is forecast to be moving over sub-20 deg C SSTs by Thursday. Thus, the cyclone only has a small window in which to sustain enough deep, organized convection to support much strengthening. Of course, if Wanda deviates from the official track and races deeper into the mid-latitudes as shown by the GFS, it would encounter even more hostile conditions and likely transition to a post-tropical cyclone sooner than forecast. The official NHC intensity forecast lies closest to the IVCN consensus aid, and allows for a bit of strengthening in the near term similar to the previous forecast.   FORECAST POSITIONS AND MAX WINDS  INIT  02/0300Z 34.5N  41.6W   40 KT  45 MPH  12H  02/1200Z 35.3N  40.9W   45 KT  50 MPH  24H  03/0000Z 36.9N  40.2W   45 KT  50 MPH  36H  03/1200Z 38.8N  39.9W   45 KT  50 MPH  48H  04/0000Z 40.9N  39.7W   45 KT  50 MPH  60H  04/1200Z 42.3N  39.2W   45 KT  50 MPH  72H  05/0000Z 42.9N  38.0W   45 KT  50 MPH  96H  06/0000Z 43.2N  33.4W   45 KT  50 MPH...POST-TROPICAL 120H  07/0000Z 43.0N  29.0W   40 KT  45 MPH...POST-TROPICAL  $$ Forecaster Reinhart  

  000 WTNT31 KNHC 020237 TCPAT1  BULLETIN Tropical Storm Wanda Advisory Number   9 NWS National Hurricane Center Miami FL       AL212021 300 AM GMT Tue Nov 02 2021  ...WANDA REMAINS A SHEARED TROPICAL CYCLONE OVER OPEN WATERS...   SUMMARY OF 300 AM GMT...0300 UTC...INFORMATION ---------------------------------------------- LOCATION...34.5N 41.6W ABOUT 845 MI...1365 KM WSW OF THE AZORES MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...ENE OR 75 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...996 MB...29.42 INCHES   WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect.   DISCUSSION AND OUTLOOK ---------------------- At 300 AM GMT (0300 UTC), the center of Tropical Storm Wanda was located near latitude 34.5 North, longitude 41.6 West.  Wanda is moving toward the east-northeast near 7 mph (11 km/h).  A turn toward the northeast is expected today, followed by a slightly faster northward motion tonight and Wednesday.  Maximum sustained winds are near 45 mph (75 km/h) with higher gusts. Little change in strength is expected through midweek.  Tropical-storm-force winds extend outward up to 45 miles (75 km) from the center.  The estimated minimum central pressure is 996 mb (29.42 inches).   HAZARDS AFFECTING LAND ---------------------- None.   NEXT ADVISORY ------------- Next complete advisory at 900 AM GMT.  $$ Forecaster Reinhart  

Coastal Watches/Warnings and Forecast Cone for Storm Center

* If the storm is forecast to dissipate within 3 days, the “Full Forecast” and “3 day” graphic will be identical

Click Here for a 5-day Cone Printer Friendly Graphic

How to use the cone graphic (video):

About this product:

NHC tropical cyclone forecast tracks can be in error. This forecast uncertainty is conveyed by the track forecast “cone”, the solid white and stippled white areas in the graphic. The solid white area depicts the track forecast uncertainty for days 1-3 of the forecast, while the stippled area depicts the uncertainty on days 4-5. Historical data indicate that the entire 5-day path of the center of the tropical cyclone will remain within the cone about 60-70% of the time. To form the cone, a set of imaginary circles are placed along the forecast track at the 12, 24, 36, 48, 72, 96, and 120 h positions, where the size of each circle is set so that it encloses 67% of the previous five years official forecast errors. The cone is then formed by smoothly connecting the area swept out by the set of circles.

It is also important to realize that a tropical cyclone is not a point. Their effects can span many hundreds of miles from the center. The area experiencing hurricane force (one-minute average wind speeds of at least 74 mph) and tropical storm force (one-minute average wind speeds of 39-73 mph) winds can extend well beyond the white areas shown enclosing the most likely track area of the center. The distribution of hurricane and tropical storm force winds in this tropical cyclone can be seen in the Wind History graphic linked above.

Considering the combined forecast uncertainties in track, intensity, and size, the chances that any particular location will experience winds of 34 kt (tropical storm force), 50 kt, or 64 kt (hurricane force) from this tropical cyclone are presented in tabular form for selected locations and forecast positions. This information is also presented in graphical form for the 34 kt, 50 kt, and 64 kt thresholds.

Note:  A detailed definition of the NHC track forecast cone is also available.

  000 WTNT41 KNHC 012049 TCDAT1  Tropical Storm Wanda Discussion Number   8 NWS National Hurricane Center Miami FL       AL212021 900 PM GMT Mon Nov 01 2021  Wanda is now moving east-northeastward and, as a result, has moved  to the east of the upper-level trough axis, while the parent  upper-low has detached and pulled out to the north. As a result,  Wanda has now made the transition from a subtropical cyclone to a  tropical cyclone. This meteorological metamorphosis has been  confirmed by ASCAT data from 1200-1300 UTC that showed Wanda now has  a small radius of maximum winds (RMW) of 30-35 nmi, and that the  outer wind field has weakened and also contracted in size. The  intensity is being held at 40 kt based on the earlier ASCAT data  showing winds of 33-34 kt, and assuming that there is undersampling  owing to the relatively large footprint/resolution of the  scatterometer instrument.  The initial motion estimate is 070/06 kt. A complex steering flow  pattern is forecast to evolve across the northern Atlantic during  the next several days as a series of troughs and ridges in the  mid-latitude westerlies pass over and to the north of Wanda. This  will cause Wanda to make a zig-zag track across the north-central  Atlantic, moving poleward ahead of the troughs and equatorward ahead  of the ridges, resulting in a net eastward propagation toward the  western Azores. The latest NHC model guidance is in fairly good  agreement on the forecast track through day 3, but then diverge on  days 4 and 5, with the GFS and ECMWF taking the cyclone more  southward closer to the Azores and the remaining dynamical models  lifting out Wanda to the north of the Azores. The new NHC official  track forecast is similar to the previous advisory track, and  follows a blend of the GFEX (GFS-ECMWF) and TVCA simple-consensus  models.  Some slight restrengthening will be possible during the next 48 h  or so due to a significant decrease in the deep-layer vertical wind  shear while Wanda moves over slightly warmer sea-surface  temperatures (SST) near 24 deg C. By 96-120 h, Wanda is forecast to  devolve into a post-tropical cyclone due to the unfavorable  combination of sub-20-deg-C SSTs, a significantly drier air mass,  and strong southerly wind shear in excess of 30 kt. The new NHC  intensity forecast remains unchanged from the previous advisory and  is basically in the middle of the tightly packed intensity guidance  suite.   FORECAST POSITIONS AND MAX WINDS  INIT  01/2100Z 34.2N  42.2W   40 KT  45 MPH  12H  02/0600Z 34.7N  41.3W   45 KT  50 MPH  24H  02/1800Z 36.0N  40.4W   45 KT  50 MPH  36H  03/0600Z 37.8N  40.0W   45 KT  50 MPH  48H  03/1800Z 39.9N  39.7W   45 KT  50 MPH  60H  04/0600Z 41.7N  39.4W   45 KT  50 MPH  72H  04/1800Z 42.8N  38.3W   45 KT  50 MPH  96H  05/1800Z 43.4N  33.3W   45 KT  50 MPH...POST-TROPICAL 120H  06/1800Z 42.5N  31.0W   40 KT  45 MPH...POST-TROPICAL  $$ Forecaster Stewart  

  637  WTNT31 KNHC 012048 TCPAT1  BULLETIN Tropical Storm Wanda Advisory Number   8 NWS National Hurricane Center Miami FL       AL212021 900 PM GMT Mon Nov 01 2021  ...WANDA TRANSITIONS TO A TROPICAL CYCLONE OVER THE NORTH-CENTRAL ATLANTIC OCEAN...   SUMMARY OF 900 PM GMT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...34.2N 42.2W ABOUT 885 MI...1425 KM WSW OF THE AZORES MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...ENE OR 70 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...996 MB...29.42 INCHES   WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect.   DISCUSSION AND OUTLOOK ---------------------- At 900 PM GMT (2100 UTC), the center of Tropical Storm Wanda was located near latitude 34.2 North, longitude 42.2 West. Wanda is moving toward the east-northeast near 7 mph (11 km/h), and this  general motion should continue through early this evening.   A turn toward the northeast is forecast to occur tonight, followed  by a turn toward the north by Tuesday night.  Maximum sustained winds are near 45 mph (75 km/h) with higher gusts.  Some slight strengthening will be possible during the next couple of  days.  Tropical-storm-force winds extend outward up to 45 miles (75 km) from the center.  The estimated minimum central pressure is 996 mb (29.42 inches).   HAZARDS AFFECTING LAND ---------------------- None.   NEXT ADVISORY ------------- Next complete advisory at 300 AM GMT.  $$ Forecaster Stewart   

Coastal Watches/Warnings and Forecast Cone for Storm Center

* If the storm is forecast to dissipate within 3 days, the “Full Forecast” and “3 day” graphic will be identical

Click Here for a 5-day Cone Printer Friendly Graphic

How to use the cone graphic (video):

About this product:

NHC tropical cyclone forecast tracks can be in error. This forecast uncertainty is conveyed by the track forecast “cone”, the solid white and stippled white areas in the graphic. The solid white area depicts the track forecast uncertainty for days 1-3 of the forecast, while the stippled area depicts the uncertainty on days 4-5. Historical data indicate that the entire 5-day path of the center of the tropical cyclone will remain within the cone about 60-70% of the time. To form the cone, a set of imaginary circles are placed along the forecast track at the 12, 24, 36, 48, 72, 96, and 120 h positions, where the size of each circle is set so that it encloses 67% of the previous five years official forecast errors. The cone is then formed by smoothly connecting the area swept out by the set of circles.

It is also important to realize that a tropical cyclone is not a point. Their effects can span many hundreds of miles from the center. The area experiencing hurricane force (one-minute average wind speeds of at least 74 mph) and tropical storm force (one-minute average wind speeds of 39-73 mph) winds can extend well beyond the white areas shown enclosing the most likely track area of the center. The distribution of hurricane and tropical storm force winds in this tropical cyclone can be seen in the Wind History graphic linked above.

Considering the combined forecast uncertainties in track, intensity, and size, the chances that any particular location will experience winds of 34 kt (tropical storm force), 50 kt, or 64 kt (hurricane force) from this tropical cyclone are presented in tabular form for selected locations and forecast positions. This information is also presented in graphical form for the 34 kt, 50 kt, and 64 kt thresholds.

Note:  A detailed definition of the NHC track forecast cone is also available.

  000 WTNT41 KNHC 011445 TCDAT1  Subtropical Storm Wanda Discussion Number   7 NWS National Hurricane Center Miami FL       AL212021 300 PM GMT Mon Nov 01 2021  Wanda has been moving southeastward since the previous advisory and  has now moved back underneath the axis of the upper-level trough  that the cyclone is embedded in. However, strong northwesterly  vertical wind shear of 30-35 kt has persisted and has displaced the  deep convection into the southeastern quadrant. The initial  intensity has been lowered to 40 kt based on a blend of satellite  intensity estimates of 35 kt from TAFB, and 39 kt and 41 kt from  UW-CIMSS ADT and SATCON, respectively.  Although Wanda had been moving southeastward at 10-11 kt as of 1200  UTC, the most recent motion vector appears to be slowly eastward or  090/05 kt. Wanda and the parent upper-level trough should move  eastward this late morning and early afternoon, and then turn  northeastward by this evening, followed by a northward motion by  late Tuesday as southerly steering flow gradually develops between a  larger mid-latitude trough to the west and a ridge to the east. By  day 3, another mid-latitude ridge is forecast to build between Wanda  and the aforementioned larger trough, causing the cyclone to turn  eastward and then southward toward the westernmost Azores.  The  latest NHC track guidance has shifted sharply to the east of the  previous forecast track through 72 hours, and the new official track  forecast has followed suit. However, the new advisory track lies  along the western edge of the guidance through day 3, and then lies  in the middle of the track guidance envelope on days 4 and 5.  Although Wanda has weakened slightly, some slight restrengthening  will be possible in the 24-60-h period when the shear is forecast to  decrease sharply down to around 10 kt while the cyclone remains over  23.5-24-deg-C sea-surface temperatures. The weaker shear conditions  should also help Wanda transition to a tropical cyclone. By 96 h,  however, Wanda is forecast to devolve into a post-tropical low due  to the cyclone moving over sub-20-deg-C water temperatures, into a  significantly drier air mass, and into strong southerly vertical  wind shear -- a detrimental combination that should cause the  convection to erode near the center.  The new NHC intensity forecast  is essentially unchanged from the previous advisory.   FORECAST POSITIONS AND MAX WINDS  INIT  01/1500Z 34.0N  43.0W   40 KT  45 MPH  12H  02/0000Z 34.1N  42.0W   40 KT  45 MPH  24H  02/1200Z 35.0N  41.1W   45 KT  50 MPH...TROPICAL CYCLONE  36H  03/0000Z 36.8N  40.2W   45 KT  50 MPH  48H  03/1200Z 39.0N  40.0W   45 KT  50 MPH  60H  04/0000Z 40.8N  39.7W   45 KT  50 MPH  72H  04/1200Z 42.3N  39.0W   45 KT  50 MPH  96H  05/1200Z 43.6N  34.0W   45 KT  50 MPH...POST-TROPICAL 120H  06/1200Z 42.9N  31.5W   40 KT  45 MPH...POST-TROPICAL  $$ Forecaster Stewart