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000
WTPZ44 KNHC 010848
TCDEP4

TROPICAL STORM ISELLE DISCUSSION NUMBER   3
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092014
200 AM PDT FRI AUG 01 2014

Iselle is continuing on an intensification trend with very deep
convection in a central dense overcast feature.  A recent AMSU
microwave pass also suggests that the inner core has become better
defined, with perhaps a partial eyewall in the eastern semicircle.
The initial wind speed is raised to 50 kt based on an ASCAT-B pass
from 0507 UTC.

Environmental conditions appear conducive for further strengthening
over the next couple of days with light-to-moderate northeasterly
shear and warm water.  Although the SHIPS-RI index has decreased
somewhat from the last cycle, rapid intensification remains a
possibility, especially given the recent development of inner core
features.  The NHC forecast is raised from the previous one, on the
higher side of the guidance envelope close to the SHIPS and FSSE
models.  After 48 hours, Iselle should be moving into a more stable
environment near cooler SSTs.  Thus, a gradual weakening is
forecast, near or slightly above the intensity consensus.

Iselle continues to move to the west-northwest while it remains to
the south of the subtropical ridge.  Global models are in excellent
agreement on this general track for the next 3 days while the ridge
persists.  After that time, the track uncertainty greatly increases
due to a trough digging into the eastern Pacific, near or east of
the forecast longitude of Iselle.  With many varying solutions from
the global models, it makes sense to stay close to the track
consensus, which generally moves Iselle westward at long range.
Since this consensus is near the last NHC prediction, the new
forecast is basically unchanged from 6 hours ago.


FORECAST POSITIONS AND MAX WINDS

INIT  01/0900Z 13.5N 124.6W   50 KT  60 MPH
 12H  01/1800Z 14.1N 125.9W   60 KT  70 MPH
 24H  02/0600Z 14.8N 127.6W   70 KT  80 MPH
 36H  02/1800Z 15.3N 129.4W   75 KT  85 MPH
 48H  03/0600Z 15.8N 131.3W   75 KT  85 MPH
 72H  04/0600Z 16.5N 134.8W   70 KT  80 MPH
 96H  05/0600Z 16.8N 137.5W   60 KT  70 MPH
120H  06/0600Z 17.0N 140.5W   50 KT  60 MPH

$$
Forecaster Blake






000
WTPZ44 KNHC 010848
TCDEP4

TROPICAL STORM ISELLE DISCUSSION NUMBER   3
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092014
200 AM PDT FRI AUG 01 2014

Iselle is continuing on an intensification trend with very deep
convection in a central dense overcast feature.  A recent AMSU
microwave pass also suggests that the inner core has become better
defined, with perhaps a partial eyewall in the eastern semicircle.
The initial wind speed is raised to 50 kt based on an ASCAT-B pass
from 0507 UTC.

Environmental conditions appear conducive for further strengthening
over the next couple of days with light-to-moderate northeasterly
shear and warm water.  Although the SHIPS-RI index has decreased
somewhat from the last cycle, rapid intensification remains a
possibility, especially given the recent development of inner core
features.  The NHC forecast is raised from the previous one, on the
higher side of the guidance envelope close to the SHIPS and FSSE
models.  After 48 hours, Iselle should be moving into a more stable
environment near cooler SSTs.  Thus, a gradual weakening is
forecast, near or slightly above the intensity consensus.

Iselle continues to move to the west-northwest while it remains to
the south of the subtropical ridge.  Global models are in excellent
agreement on this general track for the next 3 days while the ridge
persists.  After that time, the track uncertainty greatly increases
due to a trough digging into the eastern Pacific, near or east of
the forecast longitude of Iselle.  With many varying solutions from
the global models, it makes sense to stay close to the track
consensus, which generally moves Iselle westward at long range.
Since this consensus is near the last NHC prediction, the new
forecast is basically unchanged from 6 hours ago.


FORECAST POSITIONS AND MAX WINDS

INIT  01/0900Z 13.5N 124.6W   50 KT  60 MPH
 12H  01/1800Z 14.1N 125.9W   60 KT  70 MPH
 24H  02/0600Z 14.8N 127.6W   70 KT  80 MPH
 36H  02/1800Z 15.3N 129.4W   75 KT  85 MPH
 48H  03/0600Z 15.8N 131.3W   75 KT  85 MPH
 72H  04/0600Z 16.5N 134.8W   70 KT  80 MPH
 96H  05/0600Z 16.8N 137.5W   60 KT  70 MPH
120H  06/0600Z 17.0N 140.5W   50 KT  60 MPH

$$
Forecaster Blake





000
WTNT43 KNHC 010847
TCDAT3

TROPICAL STORM BERTHA DISCUSSION NUMBER   2
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL032014
500 AM AST FRI AUG 01 2014

Bertha is a sheared tropical cyclone with the center located on the
western edge of the deep convection as indicated by satellite. The
low-level circulation continues to be vigorous, but given the
current westerly shear the outflow is very limited. There are no
reasons to change the initial intensity which is kept at 40 knots.
Another Air Force reconnaissance plane will investigate Bertha in
the next several hours.

The current shear environment is not particularly favorable for
strengthening, but there are some indications by the global models
that the shear could decrease some as Bertha moves across the
northeastern Caribbean Sea. This should allow some slight
intensification during the next 24 to 36 hours. Once Bertha`s
circulation moves away from Hispaniola beyond 48 hours, there is an
opportunity for additional strengthening if the shear becomes
lighter as suggested by global and statistical models. At this time,
the NHC forecast keeps Bertha with 45-knot winds over the
western Atlantic until it becomes more certain that the shear could
subside.

Bertha continues racing toward the west-northwest or 290 degrees
at 17 knots. The cyclone is being steered by the flow around the
Atlantic subtropical ridge which is forecast to persist. Once in
the western Atlantic near the eastern Bahamas, Bertha will be
steered by the southerly flow between the subtropical high
and a mid-level trough over the eastern United States. This pattern
will force Bertha to turn northward with a decrease in forward speed
and to eventually recurve northeastward over the Atlantic. The
confidence in the track forecast, primarily in the next 2 to 3
days, is high since most the guidance is tightly clustered. The
confidence decreases after 3 days when the guidance becomes
divergent. The track envelope, however, brings Bertha northward
and then northeastward over the Atlantic, and the NHC forecast
follows closely the multi-model consensus.


FORECAST POSITIONS AND MAX WINDS

INIT  01/0900Z 13.0N  57.0W   40 KT  45 MPH
 12H  01/1800Z 14.0N  59.6W   40 KT  45 MPH
 24H  02/0600Z 15.5N  63.0W   40 KT  45 MPH
 36H  02/1800Z 17.2N  66.0W   45 KT  50 MPH
 48H  03/0600Z 19.5N  68.8W   45 KT  50 MPH
 72H  04/0600Z 24.5N  73.5W   45 KT  50 MPH
 96H  05/0600Z 29.0N  74.0W   45 KT  50 MPH
120H  06/0600Z 35.0N  67.5W   45 KT  50 MPH

$$
Forecaster Avila






000
WTNT43 KNHC 010847
TCDAT3

TROPICAL STORM BERTHA DISCUSSION NUMBER   2
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL032014
500 AM AST FRI AUG 01 2014

Bertha is a sheared tropical cyclone with the center located on the
western edge of the deep convection as indicated by satellite. The
low-level circulation continues to be vigorous, but given the
current westerly shear the outflow is very limited. There are no
reasons to change the initial intensity which is kept at 40 knots.
Another Air Force reconnaissance plane will investigate Bertha in
the next several hours.

The current shear environment is not particularly favorable for
strengthening, but there are some indications by the global models
that the shear could decrease some as Bertha moves across the
northeastern Caribbean Sea. This should allow some slight
intensification during the next 24 to 36 hours. Once Bertha`s
circulation moves away from Hispaniola beyond 48 hours, there is an
opportunity for additional strengthening if the shear becomes
lighter as suggested by global and statistical models. At this time,
the NHC forecast keeps Bertha with 45-knot winds over the
western Atlantic until it becomes more certain that the shear could
subside.

Bertha continues racing toward the west-northwest or 290 degrees
at 17 knots. The cyclone is being steered by the flow around the
Atlantic subtropical ridge which is forecast to persist. Once in
the western Atlantic near the eastern Bahamas, Bertha will be
steered by the southerly flow between the subtropical high
and a mid-level trough over the eastern United States. This pattern
will force Bertha to turn northward with a decrease in forward speed
and to eventually recurve northeastward over the Atlantic. The
confidence in the track forecast, primarily in the next 2 to 3
days, is high since most the guidance is tightly clustered. The
confidence decreases after 3 days when the guidance becomes
divergent. The track envelope, however, brings Bertha northward
and then northeastward over the Atlantic, and the NHC forecast
follows closely the multi-model consensus.


FORECAST POSITIONS AND MAX WINDS

INIT  01/0900Z 13.0N  57.0W   40 KT  45 MPH
 12H  01/1800Z 14.0N  59.6W   40 KT  45 MPH
 24H  02/0600Z 15.5N  63.0W   40 KT  45 MPH
 36H  02/1800Z 17.2N  66.0W   45 KT  50 MPH
 48H  03/0600Z 19.5N  68.8W   45 KT  50 MPH
 72H  04/0600Z 24.5N  73.5W   45 KT  50 MPH
 96H  05/0600Z 29.0N  74.0W   45 KT  50 MPH
120H  06/0600Z 35.0N  67.5W   45 KT  50 MPH

$$
Forecaster Avila





000
WTNT43 KNHC 010321
TCDAT3

TROPICAL STORM BERTHA DISCUSSION NUMBER   1
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL032014
1100 PM AST THU JUL 31 2014

Reports from an Air Force Reserve reconnaissance aircraft earlier
this afternoon and evening indicated that the well-defined low
pressure system located about 250 nmi east-southeast of Barbados had
surface winds of about 40 kt north and northeast of the center.
Since the departure of the aircraft, a band of deep convection has
developed near and to the north and east of the low-level center,
and now has enough organization to consider this system a tropical
cyclone.

The initial motion estimate is 290/17 kt. Bertha is moving along
the southern periphery of a strong subtropical ridge located to the
north based on earlier dropsonde data obtained by a NOAA
Gulfstream-IV jet aircraft. The NHC model guidance is in excellent
agreement on the cyclone maintaining a general west-northwestward
motion for the next 48 hours or so, followed by a gradual turn
toward the northwest after that through 96 hours. By Day 5, Bertha
is expected to turn northward as it moves around the western portion
of the ridge. The official forecast track is similar to but slightly
north of the consensus model, TVCA.

The environment surrounding Bertha is not particularly favorable
for significant strengthening during the next two days due
to modest westerly shear and limited mid-level moisture. However,
the cyclone will be moving over increasing SSTs and within an
upper-level atmosphere that is slightly cooler than normal. The
resultant increase in instability could allow for some slight
strengthening to occur before Bertha interacts with Puerto Rico
and eastern Hispaniola in about 48 hours or so. After the cyclone
clears land, some slight re-strengthening is possible based on the
SHIPS model indicating that the vertical shear decreasing to less
than 10 kt and SSTs increasing to near 29C. The NHC intensity
forecast is similar to the consensus model ICON.

FORECAST POSITIONS AND MAX WINDS

INIT  01/0300Z 12.3N  55.5W   40 KT  45 MPH
 12H  01/1200Z 13.2N  58.0W   40 KT  45 MPH
 24H  02/0000Z 14.5N  61.4W   40 KT  45 MPH
 36H  02/1200Z 16.1N  64.7W   45 KT  50 MPH
 48H  03/0000Z 17.9N  67.9W   45 KT  50 MPH
 72H  04/0000Z 22.0N  73.0W   35 KT  40 MPH
 96H  05/0000Z 26.8N  75.2W   40 KT  45 MPH
120H  06/0000Z 32.0N  74.7W   45 KT  50 MPH

$$
Forecaster Stewart





000
WTNT43 KNHC 010321
TCDAT3

TROPICAL STORM BERTHA DISCUSSION NUMBER   1
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL032014
1100 PM AST THU JUL 31 2014

Reports from an Air Force Reserve reconnaissance aircraft earlier
this afternoon and evening indicated that the well-defined low
pressure system located about 250 nmi east-southeast of Barbados had
surface winds of about 40 kt north and northeast of the center.
Since the departure of the aircraft, a band of deep convection has
developed near and to the north and east of the low-level center,
and now has enough organization to consider this system a tropical
cyclone.

The initial motion estimate is 290/17 kt. Bertha is moving along
the southern periphery of a strong subtropical ridge located to the
north based on earlier dropsonde data obtained by a NOAA
Gulfstream-IV jet aircraft. The NHC model guidance is in excellent
agreement on the cyclone maintaining a general west-northwestward
motion for the next 48 hours or so, followed by a gradual turn
toward the northwest after that through 96 hours. By Day 5, Bertha
is expected to turn northward as it moves around the western portion
of the ridge. The official forecast track is similar to but slightly
north of the consensus model, TVCA.

The environment surrounding Bertha is not particularly favorable
for significant strengthening during the next two days due
to modest westerly shear and limited mid-level moisture. However,
the cyclone will be moving over increasing SSTs and within an
upper-level atmosphere that is slightly cooler than normal. The
resultant increase in instability could allow for some slight
strengthening to occur before Bertha interacts with Puerto Rico
and eastern Hispaniola in about 48 hours or so. After the cyclone
clears land, some slight re-strengthening is possible based on the
SHIPS model indicating that the vertical shear decreasing to less
than 10 kt and SSTs increasing to near 29C. The NHC intensity
forecast is similar to the consensus model ICON.

FORECAST POSITIONS AND MAX WINDS

INIT  01/0300Z 12.3N  55.5W   40 KT  45 MPH
 12H  01/1200Z 13.2N  58.0W   40 KT  45 MPH
 24H  02/0000Z 14.5N  61.4W   40 KT  45 MPH
 36H  02/1200Z 16.1N  64.7W   45 KT  50 MPH
 48H  03/0000Z 17.9N  67.9W   45 KT  50 MPH
 72H  04/0000Z 22.0N  73.0W   35 KT  40 MPH
 96H  05/0000Z 26.8N  75.2W   40 KT  45 MPH
120H  06/0000Z 32.0N  74.7W   45 KT  50 MPH

$$
Forecaster Stewart






000
WTPZ44 KNHC 010226
TCDEP4

TROPICAL STORM ISELLE DISCUSSION NUMBER   2
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092014
800 PM PDT THU JUL 31 2014

The satellite presentation of Iselle features an area of cold
convective tops mainly to the north and east of the estimated center
position, and the poleward outflow has been enhanced somewhat due to
an upper-level trough to the northwest. The initial intensity has
been raised to 40 kt based on a blend of the TAFB Dvorak estimate
and the latest ADT from UW-CIMSS. Conditions appear favorable for
steady intensification during the next couple of days. In fact,
rapid strengthening is a possibility during the next 24 hours with
the SHIPS RI index showing a 40 percent chance of a 25-kt increase
in the next 24 hours. After 72 hours SSTs cool somewhat along the
forecast track, which should result in gradual weakening. The NHC
intensity forecast has been adjusted upward a little from the
previous advisory and is close to or just below the SHIPS model
through the period and above the intensity consensus.

The initial motion estimate is a somewhat uncertain 290/10 given the
recent formation of the cyclone, and the initial position is a
little to the south and west of previous estimates. Overall the
track forecast reasoning has not changed, as Iselle will be steered
generally west-northwestward south of the subtropical ridge for the
next 72 hours or so. After that time, the ridge weakens as a
mid/upper-level trough digs equatorward along 135W, which should
result is a slower westward motion late in the period. The track
guidance envelope remains tightly clustered for the first 48 hours
and the only change to the NHC track during that time is a westward
adjustment due to the initial position and motion. Late in the
period the spread of the guidance increases a little, and the
envelope has shifted northward this cycle. At days 3 through 5 the
NHC track has been adjusted northward and westward, but still lies
south of the TVCE multi-model consensus.

FORECAST POSITIONS AND MAX WINDS

INIT  01/0300Z 13.2N 123.9W   40 KT  45 MPH
 12H  01/1200Z 13.8N 125.1W   50 KT  60 MPH
 24H  02/0000Z 14.6N 126.7W   60 KT  70 MPH
 36H  02/1200Z 15.2N 128.3W   65 KT  75 MPH
 48H  03/0000Z 15.6N 130.1W   70 KT  80 MPH
 72H  04/0000Z 16.5N 134.0W   70 KT  80 MPH
 96H  05/0000Z 16.5N 136.5W   60 KT  70 MPH
120H  06/0000Z 16.5N 140.0W   55 KT  65 MPH

$$
Forecaster Brennan





000
WTPZ44 KNHC 010226
TCDEP4

TROPICAL STORM ISELLE DISCUSSION NUMBER   2
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092014
800 PM PDT THU JUL 31 2014

The satellite presentation of Iselle features an area of cold
convective tops mainly to the north and east of the estimated center
position, and the poleward outflow has been enhanced somewhat due to
an upper-level trough to the northwest. The initial intensity has
been raised to 40 kt based on a blend of the TAFB Dvorak estimate
and the latest ADT from UW-CIMSS. Conditions appear favorable for
steady intensification during the next couple of days. In fact,
rapid strengthening is a possibility during the next 24 hours with
the SHIPS RI index showing a 40 percent chance of a 25-kt increase
in the next 24 hours. After 72 hours SSTs cool somewhat along the
forecast track, which should result in gradual weakening. The NHC
intensity forecast has been adjusted upward a little from the
previous advisory and is close to or just below the SHIPS model
through the period and above the intensity consensus.

The initial motion estimate is a somewhat uncertain 290/10 given the
recent formation of the cyclone, and the initial position is a
little to the south and west of previous estimates. Overall the
track forecast reasoning has not changed, as Iselle will be steered
generally west-northwestward south of the subtropical ridge for the
next 72 hours or so. After that time, the ridge weakens as a
mid/upper-level trough digs equatorward along 135W, which should
result is a slower westward motion late in the period. The track
guidance envelope remains tightly clustered for the first 48 hours
and the only change to the NHC track during that time is a westward
adjustment due to the initial position and motion. Late in the
period the spread of the guidance increases a little, and the
envelope has shifted northward this cycle. At days 3 through 5 the
NHC track has been adjusted northward and westward, but still lies
south of the TVCE multi-model consensus.

FORECAST POSITIONS AND MAX WINDS

INIT  01/0300Z 13.2N 123.9W   40 KT  45 MPH
 12H  01/1200Z 13.8N 125.1W   50 KT  60 MPH
 24H  02/0000Z 14.6N 126.7W   60 KT  70 MPH
 36H  02/1200Z 15.2N 128.3W   65 KT  75 MPH
 48H  03/0000Z 15.6N 130.1W   70 KT  80 MPH
 72H  04/0000Z 16.5N 134.0W   70 KT  80 MPH
 96H  05/0000Z 16.5N 136.5W   60 KT  70 MPH
120H  06/0000Z 16.5N 140.0W   55 KT  65 MPH

$$
Forecaster Brennan






000
WTPZ44 KNHC 312036
TCDEP4

TROPICAL STORM ISELLE DISCUSSION NUMBER   1
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092014
200 PM PDT THU JUL 31 2014

Deep convection has been wrapping up quickly during the past few
hours near the low pressure system located near 122W, and TAFB and
SAB have both provided Dvorak estimates of T2.0/30 kt.  In
addition, a partial 1800 UTC ASCAT-B pass indicated that the low is
already producing winds to tropical storm force in the eastern
semicircle.  Therefore, advisories are being initiated on Tropical
Storm Iselle, and the maximum winds are conservatively set at 35 kt.

With sea surface temperatures ahead of Iselle running between
27-28C and vertical shear not expected to be a significant limiting
factor, the storm is forecast to strengthen for at least the next 3
days.  The strengthening rate could be quick for the next day or so,
with the SHIPS rapid intensification index showing a 44 percent
chance of a 25-kt increase in winds by this time tomorrow.  The
SHIPS guidance is the most aggressive of the intensity models and
brings Iselle to hurricane status within the next 24-36 hours.  The
NHC official intensity forecast is not as high as the SHIPS model,
but since the environment looks favorable for strengthening, it does
lie a little above the intensity consensus ICON.

Iselle is located to the south of a mid-level ridge which extends
from northwestern Mexico southwestward to near 20N140W, and the
cyclone`s estimated initial motion is 295/9 kt.  In general, ridging
is expected to maintain a relatively steady west-northwestward
motion for the next several days.  Some slight decrease in forward
speed is possible by day 4 when a weakness develops within the ridge
near 135W and ridging strengthens near the Hawaiian Islands.  The
track guidance is tightly clustered for this forecast, and the NHC
track forecast lies very close to the multi-model consensus TVCE.

FORECAST POSITIONS AND MAX WINDS

INIT  31/2100Z 12.7N 122.3W   35 KT  40 MPH
 12H  01/0600Z 13.4N 123.5W   45 KT  50 MPH
 24H  01/1800Z 14.2N 125.0W   55 KT  65 MPH
 36H  02/0600Z 14.8N 126.7W   60 KT  70 MPH
 48H  02/1800Z 15.1N 128.3W   65 KT  75 MPH
 72H  03/1800Z 16.0N 132.0W   70 KT  80 MPH
 96H  04/1800Z 16.0N 135.0W   65 KT  75 MPH
120H  05/1800Z 16.0N 138.0W   60 KT  70 MPH

$$
Forecaster Berg





000
WTPZ44 KNHC 312036
TCDEP4

TROPICAL STORM ISELLE DISCUSSION NUMBER   1
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092014
200 PM PDT THU JUL 31 2014

Deep convection has been wrapping up quickly during the past few
hours near the low pressure system located near 122W, and TAFB and
SAB have both provided Dvorak estimates of T2.0/30 kt.  In
addition, a partial 1800 UTC ASCAT-B pass indicated that the low is
already producing winds to tropical storm force in the eastern
semicircle.  Therefore, advisories are being initiated on Tropical
Storm Iselle, and the maximum winds are conservatively set at 35 kt.

With sea surface temperatures ahead of Iselle running between
27-28C and vertical shear not expected to be a significant limiting
factor, the storm is forecast to strengthen for at least the next 3
days.  The strengthening rate could be quick for the next day or so,
with the SHIPS rapid intensification index showing a 44 percent
chance of a 25-kt increase in winds by this time tomorrow.  The
SHIPS guidance is the most aggressive of the intensity models and
brings Iselle to hurricane status within the next 24-36 hours.  The
NHC official intensity forecast is not as high as the SHIPS model,
but since the environment looks favorable for strengthening, it does
lie a little above the intensity consensus ICON.

Iselle is located to the south of a mid-level ridge which extends
from northwestern Mexico southwestward to near 20N140W, and the
cyclone`s estimated initial motion is 295/9 kt.  In general, ridging
is expected to maintain a relatively steady west-northwestward
motion for the next several days.  Some slight decrease in forward
speed is possible by day 4 when a weakness develops within the ridge
near 135W and ridging strengthens near the Hawaiian Islands.  The
track guidance is tightly clustered for this forecast, and the NHC
track forecast lies very close to the multi-model consensus TVCE.

FORECAST POSITIONS AND MAX WINDS

INIT  31/2100Z 12.7N 122.3W   35 KT  40 MPH
 12H  01/0600Z 13.4N 123.5W   45 KT  50 MPH
 24H  01/1800Z 14.2N 125.0W   55 KT  65 MPH
 36H  02/0600Z 14.8N 126.7W   60 KT  70 MPH
 48H  02/1800Z 15.1N 128.3W   65 KT  75 MPH
 72H  03/1800Z 16.0N 132.0W   70 KT  80 MPH
 96H  04/1800Z 16.0N 135.0W   65 KT  75 MPH
120H  05/1800Z 16.0N 138.0W   60 KT  70 MPH

$$
Forecaster Berg






000
WTPZ43 KNHC 291439
TCDEP3

POST-TROPICAL CYCLONE HERNAN DISCUSSION NUMBER  14
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP082014
800 AM PDT TUE JUL 29 2014

GOES-15 shortwave infrared imagery shows that Hernan`s surface
circulation has become elongated (north to south) and ill-defined.
The post-tropical cyclone has been devoid of significant deep
convection for over 12 hours, and regeneration is not likely due to
sea surface temperature of less than 24 deg C.  The winds associated
with the remnant low should continue to decrease, with dissipation
of the system expected in a couple of days.

The initial motion has been along a persistent west-northwest
direction, or 300/13 kt, within the low- to mid-level flow on the
periphery of the subtropical ridge to the northeast.  This general
motion should continue until the system dissipates in 48 hours.  The
NHC forecast is similar to that from the previous package and
follows the TVCE consensus.

This is the last NHC advisory on this system.  For additional
information on the remnant low of Hernan, please see High Seas
Forecasts issued by the National Weather Service under AWIPS header
NFDHSFEPI and WMO header FZPN01 KWBC.

FORECAST POSITIONS AND MAX WINDS

INIT  29/1500Z 23.5N 121.1W   30 KT  35 MPH
 12H  30/0000Z 24.3N 122.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 24H  30/1200Z 24.9N 123.9W   20 KT  25 MPH...POST-TROP/REMNT LOW
 36H  31/0000Z 25.4N 125.1W   20 KT  25 MPH...POST-TROP/REMNT LOW
 48H  31/1200Z...DISSIPATED

$$
Forecaster Roberts






000
WTPZ43 KNHC 291439
TCDEP3

POST-TROPICAL CYCLONE HERNAN DISCUSSION NUMBER  14
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP082014
800 AM PDT TUE JUL 29 2014

GOES-15 shortwave infrared imagery shows that Hernan`s surface
circulation has become elongated (north to south) and ill-defined.
The post-tropical cyclone has been devoid of significant deep
convection for over 12 hours, and regeneration is not likely due to
sea surface temperature of less than 24 deg C.  The winds associated
with the remnant low should continue to decrease, with dissipation
of the system expected in a couple of days.

The initial motion has been along a persistent west-northwest
direction, or 300/13 kt, within the low- to mid-level flow on the
periphery of the subtropical ridge to the northeast.  This general
motion should continue until the system dissipates in 48 hours.  The
NHC forecast is similar to that from the previous package and
follows the TVCE consensus.

This is the last NHC advisory on this system.  For additional
information on the remnant low of Hernan, please see High Seas
Forecasts issued by the National Weather Service under AWIPS header
NFDHSFEPI and WMO header FZPN01 KWBC.

FORECAST POSITIONS AND MAX WINDS

INIT  29/1500Z 23.5N 121.1W   30 KT  35 MPH
 12H  30/0000Z 24.3N 122.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 24H  30/1200Z 24.9N 123.9W   20 KT  25 MPH...POST-TROP/REMNT LOW
 36H  31/0000Z 25.4N 125.1W   20 KT  25 MPH...POST-TROP/REMNT LOW
 48H  31/1200Z...DISSIPATED

$$
Forecaster Roberts





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