1 year 10 months ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1140 PM CDT Mon Oct 30 2023
Valid 011200Z - 021200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
The risk for thunderstorms appears negligible across the U.S.,
Wednesday through Wednesday night.
...Discussion...
Models indicate that the sheared remnants of an initially vigorous
short wave impulse of Arctic origins will be in the process of
accelerating east-northeast of the lower Great Lakes/upper Ohio
Valley vicinity by 12Z Wednesday, before progressing across the
northern Atlantic coast late Wednesday afternoon and evening. In
the wake of this perturbation, broadly confluent, cyclonic mid-level
flow is forecast to linger across much of the nation east of the
Rockies. Beneath this regime, cold surface ridging likely will
build east-northeastward across much of the Northeast, while being
maintained along an axis across the northwestern Gulf coast through
lower Mississippi Valley and southern Appalachians vicinity.
A notable short wave trough may approach the British Columbia and
Pacific Northwest coast by late Wednesday night, further suppressing
large-scale mid-level ridging lingering across the North American
Pacific coast vicinity. This feature may be preceded by a fairly
extensive precipitation shield with embedded convection, along an
associated occluding surface cyclone and trailing frontal zone.
However, while forecast soundings inland of coastal areas depict
layers of weak elevated instability, relatively warm layers/weak
lapse rates farther aloft seem likely to minimize the potential for
more than isolated/sparse lightning strikes. The forecast mid-level
cold core appears rather modest, and is likely to remain offshore
through this period.
..Kerr.. 10/31/2023
Read more
1 year 10 months ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1140 PM CDT Mon Oct 30 2023
Valid 011200Z - 021200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
The risk for thunderstorms appears negligible across the U.S.,
Wednesday through Wednesday night.
...Discussion...
Models indicate that the sheared remnants of an initially vigorous
short wave impulse of Arctic origins will be in the process of
accelerating east-northeast of the lower Great Lakes/upper Ohio
Valley vicinity by 12Z Wednesday, before progressing across the
northern Atlantic coast late Wednesday afternoon and evening. In
the wake of this perturbation, broadly confluent, cyclonic mid-level
flow is forecast to linger across much of the nation east of the
Rockies. Beneath this regime, cold surface ridging likely will
build east-northeastward across much of the Northeast, while being
maintained along an axis across the northwestern Gulf coast through
lower Mississippi Valley and southern Appalachians vicinity.
A notable short wave trough may approach the British Columbia and
Pacific Northwest coast by late Wednesday night, further suppressing
large-scale mid-level ridging lingering across the North American
Pacific coast vicinity. This feature may be preceded by a fairly
extensive precipitation shield with embedded convection, along an
associated occluding surface cyclone and trailing frontal zone.
However, while forecast soundings inland of coastal areas depict
layers of weak elevated instability, relatively warm layers/weak
lapse rates farther aloft seem likely to minimize the potential for
more than isolated/sparse lightning strikes. The forecast mid-level
cold core appears rather modest, and is likely to remain offshore
through this period.
..Kerr.. 10/31/2023
Read more
1 year 10 months ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1140 PM CDT Mon Oct 30 2023
Valid 011200Z - 021200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
The risk for thunderstorms appears negligible across the U.S.,
Wednesday through Wednesday night.
...Discussion...
Models indicate that the sheared remnants of an initially vigorous
short wave impulse of Arctic origins will be in the process of
accelerating east-northeast of the lower Great Lakes/upper Ohio
Valley vicinity by 12Z Wednesday, before progressing across the
northern Atlantic coast late Wednesday afternoon and evening. In
the wake of this perturbation, broadly confluent, cyclonic mid-level
flow is forecast to linger across much of the nation east of the
Rockies. Beneath this regime, cold surface ridging likely will
build east-northeastward across much of the Northeast, while being
maintained along an axis across the northwestern Gulf coast through
lower Mississippi Valley and southern Appalachians vicinity.
A notable short wave trough may approach the British Columbia and
Pacific Northwest coast by late Wednesday night, further suppressing
large-scale mid-level ridging lingering across the North American
Pacific coast vicinity. This feature may be preceded by a fairly
extensive precipitation shield with embedded convection, along an
associated occluding surface cyclone and trailing frontal zone.
However, while forecast soundings inland of coastal areas depict
layers of weak elevated instability, relatively warm layers/weak
lapse rates farther aloft seem likely to minimize the potential for
more than isolated/sparse lightning strikes. The forecast mid-level
cold core appears rather modest, and is likely to remain offshore
through this period.
..Kerr.. 10/31/2023
Read more
1 year 10 months ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1140 PM CDT Mon Oct 30 2023
Valid 011200Z - 021200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
The risk for thunderstorms appears negligible across the U.S.,
Wednesday through Wednesday night.
...Discussion...
Models indicate that the sheared remnants of an initially vigorous
short wave impulse of Arctic origins will be in the process of
accelerating east-northeast of the lower Great Lakes/upper Ohio
Valley vicinity by 12Z Wednesday, before progressing across the
northern Atlantic coast late Wednesday afternoon and evening. In
the wake of this perturbation, broadly confluent, cyclonic mid-level
flow is forecast to linger across much of the nation east of the
Rockies. Beneath this regime, cold surface ridging likely will
build east-northeastward across much of the Northeast, while being
maintained along an axis across the northwestern Gulf coast through
lower Mississippi Valley and southern Appalachians vicinity.
A notable short wave trough may approach the British Columbia and
Pacific Northwest coast by late Wednesday night, further suppressing
large-scale mid-level ridging lingering across the North American
Pacific coast vicinity. This feature may be preceded by a fairly
extensive precipitation shield with embedded convection, along an
associated occluding surface cyclone and trailing frontal zone.
However, while forecast soundings inland of coastal areas depict
layers of weak elevated instability, relatively warm layers/weak
lapse rates farther aloft seem likely to minimize the potential for
more than isolated/sparse lightning strikes. The forecast mid-level
cold core appears rather modest, and is likely to remain offshore
through this period.
..Kerr.. 10/31/2023
Read more
1 year 10 months ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1140 PM CDT Mon Oct 30 2023
Valid 011200Z - 021200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
The risk for thunderstorms appears negligible across the U.S.,
Wednesday through Wednesday night.
...Discussion...
Models indicate that the sheared remnants of an initially vigorous
short wave impulse of Arctic origins will be in the process of
accelerating east-northeast of the lower Great Lakes/upper Ohio
Valley vicinity by 12Z Wednesday, before progressing across the
northern Atlantic coast late Wednesday afternoon and evening. In
the wake of this perturbation, broadly confluent, cyclonic mid-level
flow is forecast to linger across much of the nation east of the
Rockies. Beneath this regime, cold surface ridging likely will
build east-northeastward across much of the Northeast, while being
maintained along an axis across the northwestern Gulf coast through
lower Mississippi Valley and southern Appalachians vicinity.
A notable short wave trough may approach the British Columbia and
Pacific Northwest coast by late Wednesday night, further suppressing
large-scale mid-level ridging lingering across the North American
Pacific coast vicinity. This feature may be preceded by a fairly
extensive precipitation shield with embedded convection, along an
associated occluding surface cyclone and trailing frontal zone.
However, while forecast soundings inland of coastal areas depict
layers of weak elevated instability, relatively warm layers/weak
lapse rates farther aloft seem likely to minimize the potential for
more than isolated/sparse lightning strikes. The forecast mid-level
cold core appears rather modest, and is likely to remain offshore
through this period.
..Kerr.. 10/31/2023
Read more
1 year 10 months ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1155 PM CDT Mon Oct 30 2023
Valid 311200Z - 011200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Little thunderstorm activity is expected across the Lower 48 today.
...Synopsis...
A large-scale upper trough will sweep eastward across the upper
Great Lakes and into the middle and lower MS Valley during the day,
reaching into the northeastern states and to the Appalachians by 12Z
Wed. Strong northwest flow aloft will exist behind this trough,
from the Plains into the Southeast, resulting in a stable pattern
for thunderstorms.
At the surface, high pressure will be centered over the Plains, with
strong northerly winds across the Gulf of Mexico and off the East
Coast. Given this flow regime, any appreciable low-level moisture
will be largely offshore.
Weak low-level instability may develop beneath the upper low where
lapse rates will be steep, and with the aid of moist winds across
the Great Lakes. The most likely area for a few lightning flashes
appears to be near Lake MI as a reinforcing cold front enhances
low-level convergence. Inversion heights will rise during the
evening farther east toward Lake Erie as well, and isolated
lightning flashes cannot be ruled out with any lake-enhanced,
convective showers.
..Jewell/Squitieri.. 10/31/2023
Read more
1 year 10 months ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1155 PM CDT Mon Oct 30 2023
Valid 311200Z - 011200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Little thunderstorm activity is expected across the Lower 48 today.
...Synopsis...
A large-scale upper trough will sweep eastward across the upper
Great Lakes and into the middle and lower MS Valley during the day,
reaching into the northeastern states and to the Appalachians by 12Z
Wed. Strong northwest flow aloft will exist behind this trough,
from the Plains into the Southeast, resulting in a stable pattern
for thunderstorms.
At the surface, high pressure will be centered over the Plains, with
strong northerly winds across the Gulf of Mexico and off the East
Coast. Given this flow regime, any appreciable low-level moisture
will be largely offshore.
Weak low-level instability may develop beneath the upper low where
lapse rates will be steep, and with the aid of moist winds across
the Great Lakes. The most likely area for a few lightning flashes
appears to be near Lake MI as a reinforcing cold front enhances
low-level convergence. Inversion heights will rise during the
evening farther east toward Lake Erie as well, and isolated
lightning flashes cannot be ruled out with any lake-enhanced,
convective showers.
..Jewell/Squitieri.. 10/31/2023
Read more
1 year 10 months ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1155 PM CDT Mon Oct 30 2023
Valid 311200Z - 011200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Little thunderstorm activity is expected across the Lower 48 today.
...Synopsis...
A large-scale upper trough will sweep eastward across the upper
Great Lakes and into the middle and lower MS Valley during the day,
reaching into the northeastern states and to the Appalachians by 12Z
Wed. Strong northwest flow aloft will exist behind this trough,
from the Plains into the Southeast, resulting in a stable pattern
for thunderstorms.
At the surface, high pressure will be centered over the Plains, with
strong northerly winds across the Gulf of Mexico and off the East
Coast. Given this flow regime, any appreciable low-level moisture
will be largely offshore.
Weak low-level instability may develop beneath the upper low where
lapse rates will be steep, and with the aid of moist winds across
the Great Lakes. The most likely area for a few lightning flashes
appears to be near Lake MI as a reinforcing cold front enhances
low-level convergence. Inversion heights will rise during the
evening farther east toward Lake Erie as well, and isolated
lightning flashes cannot be ruled out with any lake-enhanced,
convective showers.
..Jewell/Squitieri.. 10/31/2023
Read more
1 year 10 months ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1155 PM CDT Mon Oct 30 2023
Valid 311200Z - 011200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Little thunderstorm activity is expected across the Lower 48 today.
...Synopsis...
A large-scale upper trough will sweep eastward across the upper
Great Lakes and into the middle and lower MS Valley during the day,
reaching into the northeastern states and to the Appalachians by 12Z
Wed. Strong northwest flow aloft will exist behind this trough,
from the Plains into the Southeast, resulting in a stable pattern
for thunderstorms.
At the surface, high pressure will be centered over the Plains, with
strong northerly winds across the Gulf of Mexico and off the East
Coast. Given this flow regime, any appreciable low-level moisture
will be largely offshore.
Weak low-level instability may develop beneath the upper low where
lapse rates will be steep, and with the aid of moist winds across
the Great Lakes. The most likely area for a few lightning flashes
appears to be near Lake MI as a reinforcing cold front enhances
low-level convergence. Inversion heights will rise during the
evening farther east toward Lake Erie as well, and isolated
lightning flashes cannot be ruled out with any lake-enhanced,
convective showers.
..Jewell/Squitieri.. 10/31/2023
Read more
1 year 10 months ago
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1155 PM CDT Mon Oct 30 2023
Valid 311200Z - 011200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Little thunderstorm activity is expected across the Lower 48 today.
...Synopsis...
A large-scale upper trough will sweep eastward across the upper
Great Lakes and into the middle and lower MS Valley during the day,
reaching into the northeastern states and to the Appalachians by 12Z
Wed. Strong northwest flow aloft will exist behind this trough,
from the Plains into the Southeast, resulting in a stable pattern
for thunderstorms.
At the surface, high pressure will be centered over the Plains, with
strong northerly winds across the Gulf of Mexico and off the East
Coast. Given this flow regime, any appreciable low-level moisture
will be largely offshore.
Weak low-level instability may develop beneath the upper low where
lapse rates will be steep, and with the aid of moist winds across
the Great Lakes. The most likely area for a few lightning flashes
appears to be near Lake MI as a reinforcing cold front enhances
low-level convergence. Inversion heights will rise during the
evening farther east toward Lake Erie as well, and isolated
lightning flashes cannot be ruled out with any lake-enhanced,
convective showers.
..Jewell/Squitieri.. 10/31/2023
Read more
1 year 10 months ago
Issued at 1000 PM CDT Sun Oct 29 2023
523
WTPZ44 KNHC 300249
TCDEP4
Tropical Storm Pilar Discussion Number 6
NWS National Hurricane Center Miami FL EP192023
1000 PM CDT Sun Oct 29 2023
A small but concentrated convective burst has been persisting near
the estimated center of the tropical cyclone tonight. After the
prior advisory, we received a fortuitous GPM microwave pass valid
at 2252 UTC that suggested the low-level circulation may have
tightened up some but was located just south of the deepest
convection. Subjective Dvorak intensity estimates were up to T2.5/35
kt form TAFB and T2.0/30 kt from SAB. The objective estimates from
ADT, SATCON, and D-PRINT/MINT are all between 34-36 kt, and thus the
latest advisory is set at 35 kt this advisory, upgrading TD19-E to
Tropical Storm Pilar.
A more pronounced east-northeastward motion appears to be starting,
estimated at 060/4 kt. A continued motion to the east-northwest is
anticipated over the next 24-48 hours as Pilar's primary steering
influences are an equatorial ridge south of the storm providing
deep-layer westerlies in addition to a mid- to upper-level cutoff
low over the northwestern Caribbean that is interrupting the more
typical ridging that would be present to the north over Mexico. The
guidance is in general agreement on this scenario, but how far east
the tropical storm gets in the next 48 h remains uncertain, with the
latest HWRF and HAFS-B runs far enough east to affect the Gulf of
Fonseca with tropical storm conditions. For this reason, the
tropical storm watch has been extended eastward to portions of the
Pacific coast of Honduras and Nicaragua this advisory. On Tuesday,
Pilar is expected to stall and move very slowly as low to mid-level
ridging attempts to build back in to the north of the tropical
cyclone and a strong cold front induces a significant gap wind flow
event in the Gulf of Tehuantepec. By the middle of this week, the
enhanced low-level flow associated with the ridge and gap winds are
forecast to push Pilar away from Central America to the
west-southwest as a weakening tropical storm. As discussed
previously, the confidence of when or how sharp this turn away from
Central America will be is low given the inconsistent model guidance
over the past day. The NHC track this cycle is just a bit closer to
the coast and a touch east of the prior track, but is roughly in
between the TVCE and HCCA consensus aids.
A small core may be starting to take shape given the earlier
microwave imagery, and the persistent area of convection that Pilar
has been maintaining over the last 3-6 hours near the estimated
center. Most of the guidance maintains this small core structure
with intensification while the storm remains embedded in moderate
(15-20 kt) easterly vertical wind shear but is over warm 28-29 C
sea-surface temperatures in a moist mid-level air environment. The
latest NHC intensity forecast still takes Pilar to near hurricane
intensity in 36 h, on the higher end of the intensity guidance but
not far off the hurricane-regional guidance solutions. Afterwards,
it seems likely a combination of the dry mid-latitude gap-wind flow
in addition to possible cool upwelling of the shallow warm waters
due to slow motion near the coast of Central America could begin a
weakening trend. If the latest HWRF and HAFS-B runs end up being
correct, land interaction could also result in weakening. The
intensity forecast beyond 48 h is a little lower than the prior
advisory, as it is looking more likely that a combination of
moderate shear and additional dry stable air could prevent the storm
from re-intensifying even after it begins to move back over warmer
ocean waters away from its own cold wake.
Key Messages:
1. Heavy rains from the tropical depression will produce flash and
urban flooding, along with mudslides in areas of higher terrain
along the Pacific coast of Central America, including El Salvador,
through Wednesday.
2. Tropical storm conditions are possible by early Tuesday into
Wednesday along portions of the Pacific coast of El Salvador,
Honduras, and Nicaragua where a Tropical Storm Watch is now in
effect. Interests elsewhere along the Pacific coast of Guatemala,
and Nicaragua should monitor the progress of this system as
additional watches or warnings could be needed tomorrow.
3. Swells generated by the depression will begin to affect portions
of the Pacific coast of Central America, including El Salvador,
beginning on Monday. These swells are likely to cause
life-threatening surf and rip current conditions.
FORECAST POSITIONS AND MAX WINDS
INIT 30/0300Z 11.0N 92.0W 35 KT 40 MPH
12H 30/1200Z 11.2N 91.3W 45 KT 50 MPH
24H 31/0000Z 11.6N 90.2W 55 KT 65 MPH
36H 31/1200Z 12.0N 89.4W 60 KT 70 MPH
48H 01/0000Z 12.3N 88.9W 55 KT 65 MPH
60H 01/1200Z 12.0N 88.9W 45 KT 50 MPH
72H 02/0000Z 11.2N 89.7W 35 KT 40 MPH
96H 03/0000Z 9.9N 93.0W 35 KT 40 MPH
120H 04/0000Z 9.0N 97.5W 35 KT 40 MPH
$$
Forecaster Papin
NHC Webmaster
1 year 10 months ago
Issued at 1000 PM CDT Sun Oct 29 2023
000
WTPZ34 KNHC 300242
TCPEP4
BULLETIN
Tropical Storm Pilar Advisory Number 6
NWS National Hurricane Center Miami FL EP192023
1000 PM CDT Sun Oct 29 2023
...DEPRESSION INTENSIFIES INTO TROPICAL STORM PILAR...
...HEAVY RAINFALL AND FLASH FLOODING EXPECTED IN CENTRAL AMERICA
THIS WEEK AS PILAR MOVES CLOSER TO LAND...
SUMMARY OF 1000 PM CDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...11.0N 92.0W
ABOUT 265 MI...425 KM SW OF SAN SALVADOR EL SALVADOR
ABOUT 395 MI...630 KM W OF MANAGUA NICARAGUA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...ENE OR 60 DEGREES AT 5 MPH...7 KM/H
MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
The government of Honduras has issued a Tropical Storm Watch for
the entire Pacific coast of Honduras including the Gulf of
Fonseca.
The government of Nicaragua has issued a Tropical Storm Watch from
the Honduras and Nicaragua border southward to Puerto Sandino.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Tropical Storm Watch is in effect for...
* Entire coast of El Salvador
* Pacific coast of Honduras including the Gulf of Fonseca
* Honduras/Nicaragua border southward to Puerto Sandino.
A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.
Interests in along the Pacific coasts of Guatemala and Nicaragua
should monitor the progress of this system.
For storm information specific to your area, please monitor
products issued by your national meteorological service.
DISCUSSION AND OUTLOOK
----------------------
At 1000 PM CDT (0300 UTC), the center of Tropical Storm Pilar was
located near latitude 11.0 North, longitude 92.0 West. Pilar is
moving toward the east-northeast near 5 mph (7 km/h) and a continued
east-northeastward motion is anticipated for the next couple of
days. On the forecast track, Pilar could be near the coast
of El Salvador on Tuesday night or early Wednesday, though the core
of the system is forecast to stay offshore.
Maximum sustained winds have increased to near 40 mph (65 km/h)
with higher gusts. Additional strengthening is forecast over the
next couple of days, and Pilar could be near hurricane strength by
Tuesday.
Tropical-storm-force winds extend outward up to 35 miles (55 km)
from the center.
The estimated minimum central pressure is 1003 mb (29.62 inches).
HAZARDS AFFECTING LAND
----------------------
Key messages for Pilar can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDEP4 and WMO header WTPZ44 KNHC
and on the web at hurricanes.gov/text/MIATCDEP4.shtml
RAINFALL: Tropical Storm Pilar is expected to produce storm total
rainfall of 5 to 10 inches, with local amounts to 15 inches, in and
around much of the Pacific coast of Central America, including the
country of El Salvador, through Wednesday. This rainfall will
produce flash and urban flooding, along with mudslides in areas of
higher terrain.
SURF: Swells generated by Pilar are expected to reach portions of
the Pacific coast of Central America on Monday. These swells are
likely to cause life-threatening surf and rip current conditions.
Please consult products from your local weather office.
WIND: Tropical storm conditions could begin in the Tropical
Storm Watch area early on Tuesday.
NEXT ADVISORY
-------------
Next intermediate advisory at 100 AM CDT.
Next complete advisory at 400 AM CDT.
$$
Forecaster Papin
NHC Webmaster