Weather

SPC Day 1 Fire Weather Outlook

Weather - Fire Weather - Fri, 10/27/2017 - 10:50
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1048 AM CDT Fri Oct 27 2017 Valid 271700Z - 281200Z The previous forecast is on track and no changes are needed. See discussion below for details. ..Leitman.. 10/27/2017 .PREV DISCUSSION... /ISSUED 0132 AM CDT Fri Oct 27 2017/ ...Synopsis... A large-scale upper trough/low will progress eastward across the central/eastern CONUS today as an upper ridge remains over the eastern Pacific and the western CONUS. At the surface, a cold front will also develop slowly east-southeastward across the lower Great Lakes, OH/TN Valleys, and Southeast through the period. An area of high pressure will reside across much of the Plains in the wake of the cold front. ...Portions of the Central Plains... Strong/gusty northerly winds will occur in a post-frontal regime across a broad portion of the central Plains today. Sustained wind speeds of 15-25 mph will be common this morning and afternoon, with some higher gusts likely. A very dry airmass behind the previously mentioned cold front and modest diurnal heating will contribute to lowered RH values in a north-south corridor from southern NE into western/central KS and eastern CO, and RH values will become reduced into the 10-20% range for multiple hours. With a lack of recent precipitation, fine fuels may be marginally receptive to large fire starts. Still, surface temperatures are expected to remain quite cool across this region, with highs generally reaching only into the mid to upper 40s. With marginal temperatures acting as a somewhat limiting factor, these forecast meteorological conditions combined with dry fine fuels support the introduction of an elevated fire weather area for part of the central Plains. ...Portions of Southern CA and the Lower CO River Valley... While the primary surface high will remain to the east of the Great Basin today, a modest enhancement to the surface pressure gradient across southern CA and the lower CO River Valley may promote generally weak northerly/northeasterly winds today and tonight in conjunction with RH values below 15%. At this time, consensus of short-term guidance indicates the surface pressure gradient will remain rather weak, and sustained winds should remain generally below 15 mph. Therefore, no elevated area has been introduced across either region. ...Please see www.spc.noaa.gov/fire for graphic product... Read more
Categories: Weather

NHC Atlantic Tropical Weather Discussion

NWS Weather - Fri, 10/27/2017 - 04:48

000
AXNT20 KNHC 270948
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
548 AM EDT Fri Oct 27 2017

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through
0945 UTC.

...SPECIAL FEATURES...

A center of low pressure interacting with a stationary front off
the coast of NE Nicaragua and E Honduras is generating numerous
heavy showers and scattered tstms currently affecting these
territories, the Cayman Islands, Jamaica, portions of E Cuba, Haiti
and the Windward Passage. Environmental conditions are expected
to be conducive for some development today and Saturday as the
system moves slowly northward over the northwestern Caribbean Sea.
Regardless of development, this system will continue to produce
locally heavy rainfall over the aforementioned territories during
the next day or two. These rains are forecast to spread northward
across portions of South Florida and the Keys on Saturday, and
over the northwestern Bahamas Saturday night and Sunday. There is
a medium chance for this system to develop into a tropical cyclone
within the next 48 hours. See latest NHC Tropical Weather Outlook
under AWIPS/WMO headers MIATWOAT/ABNT20 KNHC for more details.

...GALE WARNING...

A strong cold front will enter the NW Gulf of Mexico this afternoon,
then it will extend from the Florida panhandle to the western Bay
of Campeche Saturday. Gale force northerly winds are expected S
of 23N W of the front starting early Sunday morning through Sunday
night. See latest NHC High Seas Forecast under AWIPS/WMO headers
MIAHSFAT2/FZNT02 KNHC for more details.

...ITCZ/MONSOON TROUGH...

The monsoon trough extends from the coast of Sierra Leone near
07N12W to 06N14W where the Intertropical Convergence Zone axis
then begins and continues along 06N30W to 04N43W. Scattered
moderate convection is from 02N-10N E of 30W.

...DISCUSSION...

GULF OF MEXICO...

A broad surface ridge anchored by a 1020 mb high off the coast of
North Carolina extends SW across most of the basin, thus providing
return flow. Latest scatterometer data show fresh SSE winds in
the NW basin and gentle to moderate return flow elsewhere. The
strongest winds in the NW side of the basin is due to a tighter
pressure gradient between the ridge and building low pressure
associated with the next cold front to come off the coast of Texas
this afternoon. The front will then push across the remainder of
the basin through Sunday night. Fresh to strong N winds will
accompany the passage of the front with near to gale force winds
developing south of Tampico, Mexico and the W Bay of Campeche.

CARIBBEAN SEA...

A cold front in the SW N Atlc extends across the Windward Passage
SW to Cuba adjacent waters near 19N76W where it stalls continuing
SW to a 1007 mb low centered just E of Honduras near 15N83W.
Numerous heavy showers and scattered tstms associated with this
system are currently affecting E Honduras, Nicaragua, the Cayman
Islands, Jamaica, portions of E Cuba, Haiti, the Windward
Passage and W Caribbean waters from 10N-20N between 74W-86W.
There is a medium chance for this system to develop into a
tropical cyclone within the next 48 hours. See special features
for further details. Over the E basin, a middle to upper level
low support a surface trough just E of Puerto Rico from 21N63W to
10N65W. Isolated showers are within 120 nm either side of the
trough axis. Except for fresh to near gale force winds W of the
front and in the vicinity of the low center, gentle to moderate
trades are elsewhere. The stationary front will transition into a
warm front today, lifting towards the coastline of S Cuba before
dissipating.

...HISPANIOLA...

A cold front along the coastline of E Cuba to 19N76W becoming
stationary from that point to 15N83W will drift back along
southern Cuba through tonight. Both the front and an area of low
pressure developing off the coast of E Honduras will continue to
support scattered showers and tstms across the Windward Passage
and isolated showers across the Island through this afternoon.
However, a surface trough currently E of Puerto Rico will approach
the Island by Saturday morning with showers mainly affecting the
Dominican Republic.

ATLANTIC OCEAN...

A cold front over the western Atlantic extends from 30N66W to the
Windward Passage near 20N74W with tail becoming stationary in the
NW Caribbean. Scattered to isolated showers are within 150 nm
east of the front. The northern part of the front will weaken in
the central Atlantic today, while the southern part stalls and
drifts NW through Saturday before starting to dissipate Sunday. A
surface trough over the central and eastern Atlantic extends from
25N32W to 21N40W to 20N48W. Isolated showers are within 210 nm
either side of the boundary. Otherwise, a surface trough is
analyzed in the central Atlantic just W of the ITCZ from 13N43W to
04N45W, which is supporting scattered to isolated showers from
06N-13N between 40W-54W. Rains associated with a broad area of
low pressure in the NW Caribbean are forecast to spread northward
across portions of South Florida and the Keys on Saturday, and
over the northwestern Bahamas Saturday night and Sunday. See
special features for further details.

For additional information please visit
http://www.hurricanes.gov/marine

$$
Ramos
Categories: Weather

SPC Day 2 Fire Weather Outlook

Weather - Fire Weather - Fri, 10/27/2017 - 01:35
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0132 AM CDT Fri Oct 27 2017 Valid 281200Z - 291200Z ...NO CRITICAL AREAS... ...Synopsis... A large-scale upper trough/low will continue moving eastward on Day 2/Saturday across the central/eastern CONUS. Am upper ridge over the western CONUS will be undercut by a small upper low moving toward the coast of CA. At the surface, a cold front will also continue eastward across the OH/TN Valleys and Southeast to the East Coast through the period. A broad area of high pressure will remain over the Plains, with a weak surface high extending across parts of the Great Basin. Light offshore flow should be ongoing Saturday morning across parts of southern CA in combination with lowered RH values. Forecast sustained winds appear too weak/marginal to warrant inclusion of an elevated area at this time. Across the remainder of the CONUS, strong/gusty surface winds are not forecast to overlap critically lowered RH values and dry fuels. Therefore, no areas have been highlighted. ..Gleason.. 10/27/2017 ...Please see www.spc.noaa.gov/fire for graphic product... Read more
Categories: Weather

SPC Day 1 Fire Weather Outlook

Weather - Fire Weather - Fri, 10/27/2017 - 01:34
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0132 AM CDT Fri Oct 27 2017 Valid 271200Z - 281200Z ...Synopsis... A large-scale upper trough/low will progress eastward across the central/eastern CONUS today as an upper ridge remains over the eastern Pacific and the western CONUS. At the surface, a cold front will also develop slowly east-southeastward across the lower Great Lakes, OH/TN Valleys, and Southeast through the period. An area of high pressure will reside across much of the Plains in the wake of the cold front. ...Portions of the Central Plains... Strong/gusty northerly winds will occur in a post-frontal regime across a broad portion of the central Plains today. Sustained wind speeds of 15-25 mph will be common this morning and afternoon, with some higher gusts likely. A very dry airmass behind the previously mentioned cold front and modest diurnal heating will contribute to lowered RH values in a north-south corridor from southern NE into western/central KS and eastern CO, and RH values will become reduced into the 10-20% range for multiple hours. With a lack of recent precipitation, fine fuels may be marginally receptive to large fire starts. Still, surface temperatures are expected to remain quite cool across this region, with highs generally reaching only into the mid to upper 40s. With marginal temperatures acting as a somewhat limiting factor, these forecast meteorological conditions combined with dry fine fuels support the introduction of an elevated fire weather area for part of the central Plains. ...Portions of Southern CA and the Lower CO River Valley... While the primary surface high will remain to the east of the Great Basin today, a modest enhancement to the surface pressure gradient across southern CA and the lower CO River Valley may promote generally weak northerly/northeasterly winds today and tonight in conjunction with RH values below 15%. At this time, consensus of short-term guidance indicates the surface pressure gradient will remain rather weak, and sustained winds should remain generally below 15 mph. Therefore, no elevated area has been introduced across either region. ..Gleason.. 10/27/2017 ...Please see www.spc.noaa.gov/fire for graphic product... Read more
Categories: Weather

NHC Atlantic Tropical Weather Discussion

NWS Weather - Fri, 10/27/2017 - 01:05

000
AXNT20 KNHC 270605
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
205 AM EDT Fri Oct 27 2017

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 0000 UTC surface analysis and satellite imagery through
0545 UTC.

...SPECIAL FEATURES...

A center of low pressure interacting with a stationary front off
the coast of NE Nicaragua and E Honduras. Numerous heavy showers
and scattered tstms associated with this system are currently
affecting E Honduras, portions of Nicaragua, the Cayman Islands,
Jamaica, portions of Cuba, SW Haiti and the Windward Passage.
Environmental conditions are expected to be conducive for some
development on Friday and Saturday as the system moves slowly
northward over the northwestern Caribbean Sea. Regardless of
development, this system is expected to produce locally heavy
rainfall over the aforementioned territories during the next day
or two. These rains are forecast to spread northward across
portions of South Florida and the Keys on Saturday, and over the
northwestern Bahamas Saturday night and Sunday. There is a medium
chance for this system to develop into a tropical cyclone within
the next 48 hours.

...GALE WARNING...

A strong cold front will enter the NW Gulf of Mexico Friday
afternoon, then extend from the Florida panhandle to the western
Bay of Campeche Saturday. Gale force northerly winds are expected
S of 23N W of the front starting early Sunday morning through
Sunday night.

...ITCZ/MONSOON TROUGH...

The Intertropical Convergence Zone axis extends from 07N14W to
06N30W to 09N43W, then resumes W of a surface trough near 09N46W
to 09N57W. Scattered moderate convection is from 02N-09N E of 30W.
Similar convection is from 10N-13N between 48W-55W.

...DISCUSSION...

GULF OF MEXICO...

A broad surface ridge anchored by a 1019 mb high off the coast of
Georgia extends SW and extends across most of the basin, thus
providing return flow. Latest scatterometer data show fresh SSE
winds in the NW basin and gentle to moderate return flow
elsewhere. The strongest winds in the NW side of the basin is due
to a tighter pressure gradient between the ridge and building low
pressure associated with the next cold front to come off the coast
of Texas Friday afternoon. The front will then push across the
remainder of the basin through Sunday night. Fresh to strong N
winds will accompany the passage of the front with near to gale
force winds developing near Veracruz and the W Bay of Campeche.

CARIBBEAN SEA...

A cold front in the SW N Atlc extends across the E tip of Cuba SW
to adjacent waters near 19N76W where it stalls continuing SW to a
1008 mb low centered just E of Honduras near 15N83W. Numerous
heavy showers and scattered tstms associated with this system are
currently affecting E Honduras, portions of Nicaragua, the Cayman
Islands, Jamaica, portions of Cuba, SW Haiti and the Windward
Passage. There is a medium chance for this system to develop into
a tropical cyclone within the next 48 hours. See special features.
Over the E basin, a middle to upper level low support a surface
trough from 19N64W to 12N65W. Isolated showers are within 210 nm
either side of the trough axis. Except for fresh to near gale
force winds in the W of the front and in the vicinity of the low,
gentle to moderate trades are elsewhere.

...HISPANIOLA...

A stationary front S of eastern Cuba will drift back to the NW
Caribbean Friday as an area of low pressure develops SW of
Hispaniola. This will increase the chances for showers mainly over
Haiti, but heavy downpours are expected to remain west of the
island through Saturday.

ATLANTIC OCEAN...

A cold front over the western Atlantic extends from 30N67W to E
Cuba near 20N74W. Scattered moderate convection is within 150 nm
east of the front. The northern part of the front will weaken in
the central Atlantic Friday, while the southern part stalls and
drifts NW through Saturday. A shear line over the eastern
Atlantic extends from 28N28W to 21N49W. Isolated showers are
within 60 nm of the boundary. A surface trough is analyzed south
of 12N along 44W in the central Atlantic. It will drift westward
through Saturday.

For additional information please visit
http://www.hurricanes.gov/marine

$$
Ramos
Categories: Weather

NHC Atlantic Tropical Weather Discussion

NWS Weather - Thu, 10/26/2017 - 12:57

000
AXNT20 KNHC 261756
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
156 PM EDT Thu Oct 26 2017

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1200 UTC surface analysis and satellite imagery through
1715 UTC.

...SPECIAL FEATURES...

A cold front will enter the NW Gulf of Mexico Friday evening. On
Saturday, the front will extend from 30N87W to 23N95W to 21N96W
to 19N95W. A gale will form S of 23N W of front with NW to N
winds 30-35 kt, and SEAS 9-12 FT.

...ITCZ/MONSOON TROUGH...

The monsoon trough extends from the African coast near 12N17W to
08N20W. The Intertropical Convergence Zone axis extends from
08N20W to 06N39W. The ITCZ continues W of a surface trough from
06N42W to the coast of South America near 06N54W. Scattered
moderate convection is S of the monsoon trough from 03N- 06N
between 12W-18W. Widely scattered moderate convection is in the
vicinity of the surface trough from 05N-15N between 37W-46W.

...DISCUSSION...

GULF OF MEXICO...

A 1020 mb high is centered over the Florida Panhandle near
30N86W. 10-15 kt anticyclonic surface winds are over the Gulf of
Mexico with fair weather. Another 1020 mb high is centered over
central Mexico near 22N100W. An area of scattered to broken cold
air stratocumulus clouds are over the S Gulf from 21N-25N between
82W- 92W. In the upper levels, an upper level trough is over the
E Gulf with axis along 80W supporting the frontal system now over
the W Atlantic. Strong subsidence is over Texas, the entire Gulf
of Mexico, and Florida. Expect in 24 hours for the surface high
over the Florida Panhandle to move to North Carolina. The next
cold front will enter the NW Gulf in 30 hours, or Friday evening,
with showers. A gale will form W of the front over the SW Gulf in
48 hours, or Saturday.

CARIBBEAN SEA...

As of 1500 UTC, a cold front extends from E Cuba near 21N76W to
to NE Honduras near 16N85W. A 1009 mb low is over NE Honduras
near 15N83W. Scattered moderate to isolated strong convection is
within 150 nm S of front, to include Jamaica. In addition, widely
scattered moderate convection is over the SW Caribbean from 09N-
15N between 78W-84W. Further E, a surface trough is over the E
Caribbean from 18N63W to 10N63W. Scattered showers are E of the
trough axis. Hispaniola and Puerto Rico remain with fair weather.
Of note in the upper levels, a small upper level low is centered
over the E Caribbean near 13N67W with strong subsidence. Expect
the surface low over NE Honduras to move slowly N for the next 48
hours to W Cuba, with continued convection.

...HISPANIOLA...

Northerly dry air aloft will support fair weather across the
island through Friday. Moderate trades will also persist.

ATLANTIC OCEAN...

A cold front is over the W Atlantic from 31N69W to E Cuba near
21N76W. Scattered moderate convection is within 150 nm E of the
front. A cold front is over the E Atlantic from 31N23W to 25N30W
to 22N38W. Scattered showers are within 60 nm of the front. Of
note in the upper levels, an upper level high is centered over
the tropical Atlantic near 11N39W. Expect the two fronts to move
E over the next 24 hours with convection.

For additional information please visit
http://www.hurricanes.gov/marine

$$
Formosa

Categories: Weather

SPC Day 2 Fire Weather Outlook

Weather - Fire Weather - Thu, 10/26/2017 - 12:17
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1215 PM CDT Thu Oct 26 2017 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... No changes are needed and no fire weather concerns are expected. See discussion below for more details. ..Leitman.. 10/26/2017 .PREV DISCUSSION... /ISSUED 0124 AM CDT Thu Oct 26 2017/ ...Synopsis... A stout surface ridge will migrate southward along and east of the Continental Divide, with cooler air overspreading much of the Plains along with limited fire weather concerns. Meanwhile, a lack of distinct synoptic-scale systems across the West will result in a relatively weak surface pressure gradient and light flow in most dry areas of California and the Southwest. With quiescent fire weather conditions expected, no highlights are introduced at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more
Categories: Weather

NHC Atlantic Tropical Weather Discussion

NWS Weather - Thu, 10/26/2017 - 04:25

000
AXNT20 KNHC 260925
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
525 AM EDT Thu Oct 26 2017

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through
0915 UTC.

...ITCZ/MONSOON TROUGH...

The monsoon trough extends from the African coast near 10N14W to
07N21W. The Intertropical Convergence Zone axis extends from
07N21W to 08N40W to 05N54W. Scattered moderate convection and
isolated tstms are from 04N-11N E of 20W. Similar convection is
from 04N-17N between 31W-50W.

...DISCUSSION...

GULF OF MEXICO...

A surface ridge influences the entire basin being anchored by a
1022 mb high centered in E Mexico near 22N99W. Gentle to moderate
northerly winds prevail E of 90W and in the SW basin. These winds
will gradually reduce through this afternoon as a new center of
high pressure forms in the NW Gulf, which will drift NNE thus
providing return flow ahead of the next cold front forecast to
emerge off the Texas and Louisiana coasts Friday afternoon. Fresh
to strong northerly winds are expected behind the front as it
races SE exiting the basin Sunday afternoon.

CARIBBEAN SEA...

A middle to upper level trough over the eastern CONUS extending
into SW N Atlc waters with a base reaching western Cuba supports
a cold front analyzed across central Cuba near 21N78W to Honduras
near 15N84W. Ahead of the front, a surface trough extends from
19N79W SW into a 1008 mb low over Nicaragua adjacent waters near
14N81W. Scattered moderate convection and isolated tstms are
occurring associated with the low from 09N-17N W of 78W. Isolated
showers are within 120 nm either side of the cold front. Latest
scatterometer data show moderate to fresh northerly winds behind
the front and in the NW quadrant of the low center. Gentle to
moderate trades are elsewhere. In the central and most of the E
Caribbean, northerly flow aloft between ridging over the western
basin and an upper level low over SE waters near 13N64W is
providing overall fair conditions and mostly clear skies.
Otherwise, a surface trough just to the E of the Lesser Antilles
continues to provide focus for scattered to isolated showers E of
64W. The front will continue to race SE to E Cuba through tonight
merging with the low center. The front will then stall before
transitioning to a warm front Friday.

...HISPANIOLA...

Dry air aloft within northerly flow will support fair weather
across the island through Friday. Moderate trades are expected to
persist.

ATLANTIC OCEAN...

A middle to upper level trough extends over the eastern CONUS
across the far SW N Atlc to a base over western Cuba. The trough
supports a cold front extending from 31N72W to the central
Bahamas to the coast of Cuba near 22N77W and into the NW
Caribbean Sea. Scattered showers and tstms are occurring within
210 nm east of the front N of 21N and within 90 nm W of the front
S of 27N. Moderate to fresh NW winds are occurring W of the front
and within 135 nm ahead of it. The front is forecast to move east
and gradually weaken across the central Atlc by Sunday. A broad
middle to upper level low and associated trough over the eastern
North Atlc supports a cold front extending from 30N26W to 24N34W
to 22N47W. Isolated showers are possible within 75 nm either side
of the front.

For additional information please visit
http://www.hurricanes.gov/marine

$$
Ramos
Categories: Weather

SPC Day 2 Fire Weather Outlook

Weather - Fire Weather - Thu, 10/26/2017 - 01:26
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0124 AM CDT Thu Oct 26 2017 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... ...Synopsis... A stout surface ridge will migrate southward along and east of the Continental Divide, with cooler air overspreading much of the Plains along with limited fire weather concerns. Meanwhile, a lack of distinct synoptic-scale systems across the West will result in a relatively weak surface pressure gradient and light flow in most dry areas of California and the Southwest. With quiescent fire weather conditions expected, no highlights are introduced at this time. ..Cook.. 10/26/2017 ...Please see www.spc.noaa.gov/fire for graphic product... Read more
Categories: Weather

SPC Day 1 Fire Weather Outlook

Weather - Fire Weather - Thu, 10/26/2017 - 01:25
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0123 AM CDT Thu Oct 26 2017 Valid 261200Z - 271200Z ...Synopsis... High pressure across the Great Basin - previously responsible for heightened fire weather concerns over southern California on previous days - will weaken dramatically throughout the day while a colder airmass (with higher RH values) overspreads the northern Rockies and Plains behind a southward-moving cold front. The net result is a more quiescent fire weather scenario for most areas except for portions of the southern Rockies, where dry westerly flow will support elevated conditions during the afternoon. ...Southeastern Arizona eastward into far west Texas... Areas of 15-25 mph westerly surface flow will develop within the elevated delineation as temperatures rise into the 70s and low 80s F during the afternoon. A dry airmass will remain in place across the region, and RH values should fall to around 11-15% during peak heating hours. Where fuels are dry, elevated to locally critical conditions appear likely, although these conditions should occur on too brief of a basis to necessitate any upgrades at this time. ..Cook.. 10/26/2017 ...Please see www.spc.noaa.gov/fire for graphic product... Read more
Categories: Weather

NHC Atlantic Tropical Weather Discussion

NWS Weather - Thu, 10/26/2017 - 01:07

000
AXNT20 KNHC 260606
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
206 AM EDT Thu Oct 26 2017

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 0000 UTC surface analysis and satellite imagery through
0545 UTC.

...ITCZ/MONSOON TROUGH...

The monsoon trough extends from the African coast near 11N15W to
08N20W. The Intertropical Convergence Zone axis extends from
08N20W to 08N40W to 05N52W. Scattered moderate convection is from
03N-11N E of 18W. Similar convection is from 04N-17N between 30W-
50W.

...DISCUSSION...

GULF OF MEXICO...

A cold front now fully east of the basin continues to provide a
few lingering isolated showers across the Florida Straits and the
Yucatan Channel. Otherwise, a surface ridge influences the
remainder of the basin being anchored by a 1023 mb high centered
in E Mexico near 22N98W. Gentle to moderate northerly winds
prevail. A high is forecast to develop in the NE Gulf this
morning, which is expected to move E-NE towards the Florida Big
Bend region through this afternoon. By Thursday night, moderate
to fresh southerly return flow will re-establish across the NW
Gulf waters as the next cold front pushes southward across the
southern Great Plains. The cold front is forecast to emerge off
the Texas and Louisiana coasts Friday afternoon ushering in
another round of fresh to strong northerly winds.

CARIBBEAN SEA...

A middle to upper level trough over the eastern CONUS extending
into SW N Atlc waters with a base reaching Cuba supports a cold
front analyzed across central Cuba near 21N79W to Honduras near
15N85W. Ahead of the front, a surface trough extends from 20N78W
SW into a 1008 mb low over Nicaragua adjacent waters near 14N82W.
Scattered moderate convection and isolated tstms are occurring
ahead of the front to 75W. Isolated showers are W of the boundary
to the Yucatan Channel. Latest scatterometer data show moderate to
fresh northerly winds behind the front and N of the low center.
Gentle to moderate trades are elsewhere. In the central and most
of the E Caribbean, northerly flow aloft between ridging over the
western basin and an upper level low over SE waters near 13N64W
is providing overall fair conditions and mostly clear skies.
Otherwise, a surface trough E of the Lesser Antilles continues to
provide focus for scattered to isolated showers E of 64W. The
front will continue to race SE to E Cuba through Thursday night
and merge with the low center. The front will then stall before
transitioning to a warm front Friday.

...HISPANIOLA...

Dry air aloft within northerly flow will support fair weather
across the island through Friday. Moderate trades are expected to
persist.

ATLANTIC OCEAN...

A middle to upper level trough extends over the eastern CONUS to
a base over Cuba. The trough supports a cold front extending from
30N74W to the central Bahamas to the coast of Cuba near 22N79W
and into the NW Caribbean Sea. Scattered showers and tstms are
occurring within 210 nm east of the front N of 22N and within 150
nm W of the front S of 24N. Generally moderate to fresh NW winds
are occurring in wake of the front this evening as it is forecast
to move east and gradually weaken across the central Atlc by
Friday night. Farther east, an upper level low supports a surface
trough analyzed from 26N60W to 28N56W generating scattered
showers and isolated tstms from 24N- 30N between 47W-59W. This
area remains on the southern periphery of a surface ridge anchored
by a 1031 mb high centered north of the area near 39N57W.
Finally, an upper level trough is over the eastern North Atlc
supporting a gale force 996 mb low centered near 41N32W. The
associated cold front extends into the discussion area near 30N27W
SW to 23N42W. Isolated showers are possible within 75 nm either
side of the front.

For additional information please visit
http://www.hurricanes.gov/marine

$$
Ramos
Categories: Weather

NHC Atlantic Tropical Weather Discussion

NWS Weather - Wed, 10/25/2017 - 17:48

000
AXNT20 KNHC 252248
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
648 PM EDT Wed Oct 25 2017

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1800 UTC surface analysis and satellite imagery through
2215 UTC.

...ITCZ/MONSOON TROUGH...
The monsoon trough extends from the African coast near 10N15W to
09N22W. The Intertropical Convergence Zone axis extends from
09N22W to 08N34W to 08N46W to 05N52W. Isolated moderate convection
is from 06N-09N between 14W-20W. Scattered moderate convection is
from 02N-15N between 31W-44W...and from 08N-17N between 44W-53W.

...DISCUSSION...

GULF OF MEXICO...
A cold front now fully east of the basin continues to provide a
few lingering isolated showers across the Florida Straits and SE
Gulf this evening S of 25N E of 84W. Otherwise...a surface ridge
influences the remainder of the basin anchored by a 1027 mb high
centered across NE Mexico near 24N100W. Moderate to fresh
northerly winds prevail this evening as the high moves E-NE
towards the Florida Big Bend region through Thursday afternoon.
By Thursday night...moderate to fresh southerly return flow will
have re-established itself across the NW Gulf waters as the next
cold front pushes southward across the southern Great Plains. The
cold front is forecast to emerge off the Texas and Louisiana
coasts Friday afternoon ushering in another round of fresh to
strong northerly winds.

CARIBBEAN SEA...
A middle to upper level trough noted on water vapor imagery over
the far eastern Gulf of Mexico and Florida peninsula is supportive
of a cold front analyzed across western Cuba near 23N81W into the
NW Caribbean to the coast of Honduras near 16N87W. A pre-frontal
surface trough extends from the cold front near 22N80W southward
into a 1007 mb low centered along the coast of Nicaragua near
14N83W. Scattered scattered and tstms are occurring across a large
portion of the western Caribbean and Central America W of 76W.
Strongest convection currently is noted across the SW Caribbean
and in the vicinity of the surface low from 10N-14N between 78W-
88W. Farther east...northerly flow aloft between ridging over the
western Caribbean and an upper level low centered over the NE
Caribbean near 13N63W is providing overall fair conditions and
mostly clear skies this evening between 63W-75W. To the east of
the Lesser Antilles...surface troughing extends from 08N61W across
Barbados to 17N57W and continues to provide focus for scattered
showers and tstms primarily east of the Caribbean basin from
09N-18N between 53W-59W. The convection continues to be enhanced
due to favorable divergence aloft on the eastern periphery of the
upper level low.

...HISPANIOLA...
Dry air aloft within northerly flow will support fair weather
across the island through Thursday. Moderate trades are expected
to persist.

ATLANTIC OCEAN...
A middle to upper level trough extends over the eastern CONUS from
over the New England states S-SW over the Carolinas and Florida
peninsula to a base over the SE Gulf of Mexico. The troughing
supports a cold front extending from 32N74W to the NW Bahamas to
the coast of western Cuba near 23N80W and into the NW Caribbean
Sea. Scattered showers and tstms are occurring within 210 nm east
of the front N of 26N and within 150 nm either side of the front S
of 26N. Generally moderate to fresh NW winds are occurring in wake
of the front this evening as it is forecast to move east and
gradually weaken across the central Atlc by Friday night. Farther
east...an upper level low is centered near 29N58W and supports a
surface trough analyzed from 26N60W to 28N56W generating scattered
showers and isolated tstms from 24N-30N between 47W-59W. This area
remains on the southern periphery of a surface ridge anchored by a
1031 mb high centered north of the area near 39N57W. Finally...an
upper level trough is over the eastern North Atlc supporting a
gale force 998 mb low centered near 41N32W. The associated cold
front extends into the discussion area near 32N27W SW to 25N37W to
24N45W. Isolated showers are possible within 75 nm either side of
the front.

For additional information please visit
http://www.hurricanes.gov/marine

$$
HUFFMAN

Categories: Weather

NHC Atlantic Tropical Weather Discussion

NWS Weather - Wed, 10/25/2017 - 12:40

000
AXNT20 KNHC 251740
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
140 PM EDT Wed Oct 25 2017

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1200 UTC surface analysis and satellite imagery through
1715 UTC.

...TROPICAL WAVES...

A tropical wave is E of the Lesser Antilles with axis extending
from 19N56W to 13N59W to 07N59W, moving W at 5-10 kt. The wave is
in an area of abundant moisture as depicted on SSMI TPW imagery.
There is also a distinct 700 mb trough axis associated with this
wave. Scattered moderate to isolated strong convection is within
120 nm of the wave axis.

...ITCZ/MONSOON TROUGH...

The monsoon trough extends from the African coast near 10N14W to
08N20W. The Intertropical Convergence Zone axis extends from
08N20W to 08N42W to 07N50W to 06N55W. Aside from the convection
associated with the tropical wave, scattered moderate to isolated
strong convection is from 03N-12N between 30W-42W, and from 08N-
13N between 42W-50W.

...DISCUSSION...

GULF OF MEXICO...

As of 1500 UTC a cold front is over the Straits of Florida from
24N80W to W Cuba at 23N81W. Scattered showers are within 60 nm of
the front. A 1029 mb high is centered over N Mexico near 27N102W.
The surface pressure gradient between this high and the cold front
is rather tight thus 20-25 kt northerly winds are over the Gulf of
Mexico. Mostly fair weather is over the remainder of the Gulf. S
Mexico S of 21N to the base of the mountains, has overcast low
clouds and showers. In the upper levels, a large upper level
trough is over the Gulf with axis along 85W supporting the frontal
system now mostly over the W Atlantic. Expect in 24 hours for the
surface high to move to the NW Gulf of Mexico, with fair weather
and weaker surface winds.

CARIBBEAN SEA...

As of 1500 UTC, a cold front extends from W Cuba near 23N81W to
20N86W to the Gulf of Honduras near 16N88W. Widely scattered
moderate convection is over the NW Caribbean from 16N- 21N between
82W-88W. A surface trough extends from 20N79W to a 1008 mb low off
the coast of Nicaragua near 12N82W. Scattered moderate to strong
convection is from 10N-17N between 78W-84W. Further E, a tropical
wave is approaching the Lesser Antilles, see above. Of note in the
upper levels, an upper level ridge is over the NW Caribbean and
Central America. A small upper level low is centered over the E
Caribbean near 13N63W. Upper level diffluence E of the low is
enhancing the convection E of the Lesser Antilles. Expect the
surface low off the coast of Nicaragua to remain quasi-stationary
for the next 24 hours with continued convection. Also expect the
tropical wave to gradually move into the E Caribbean with
convection mostly E of the wave axis.

...HISPANIOLA...

Dry air northerly flow aloft will support fair weather across the
island through Thursday. Moderate trades are also expected to
persist.

ATLANTIC OCEAN...

A cold front is over the W Atlantic from 31N76W to the Straits of
Florida near 24N80W. Scattered moderate convection is within 120
nm E of the front. A cold front is over the central Atlantic from
31N29W to 25N40W to 25N46W. Scattered showers are within 90 nm of
the front. Of note in the upper levels, an upper level low is
centered over the central Atlantic near 29N59W. Widely scattered
moderate convection is from 26N-29N between 51W-57W. Expect the
two fronts to move E over the next 48 hours with convection.

For additional information please visit
http://www.hurricanes.gov/marine

$$
Formosa

Categories: Weather

SPC Day 2 Fire Weather Outlook

Weather - Fire Weather - Wed, 10/25/2017 - 10:57
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1055 AM CDT Wed Oct 25 2017 Valid 261200Z - 271200Z No changes have been made to the ongoing forecast. See the previous discussion below for more information on the elevated area for Day 2/Thursday across parts of southeastern AZ into southern NM and far west TX. ..Gleason.. 10/25/2017 .PREV DISCUSSION... /ISSUED 1239 AM CDT Wed Oct 25 2017/ ...Synopsis... A dramatically quieter day for fire weather concerns is expected Thursday as previously gusty winds across dry areas of southern California weaken substantially and a colder airmass (containing high RH values) overspreads portions of the northern Rockies and adjacent Plains. South of these areas, dry westerly flow will develop across portions of the far southern Rockies, with elevated fire weather concerns returning to these areas. ...Southeastern Arizona eastward into far west Texas... By mid-afternoon, areas of 15-20 mph westerly surface flow will develop within the elevated delineation as temperatures rise into the 70s and low 80s F. A dry airmass will remain in place across the region, and RH values should hover around/just below 15% for brief periods during peak heating hours. Where fuels are dry, an elevated fire weather threat will exist. ...Please see www.spc.noaa.gov/fire for graphic product... Read more
Categories: Weather

SPC Day 1 Fire Weather Outlook

Weather - Fire Weather - Wed, 10/25/2017 - 10:55
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1054 AM CDT Wed Oct 25 2017 Valid 251700Z - 261200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN CALIFORNIA... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL/EASTERN MONTANA... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN WYOMING AND FAR WESTERN NEBRASKA... The critical area across portions of central/eastern MT has been expanded westward/northward based on latest surface observations and short-term model guidance. Critical fire weather conditions are already ongoing across the lower elevations of central MT, and these conditions will spread eastward by this afternoon. The critical area across parts of southeastern WY and far western NE has been expanded slightly northward and southward. Downslope westerly flow of 20-25 mph off the Laramie Range will support warming/drying of low levels, and RH values will fall into the 10-15% range for multiple hours this afternoon in conjunction with dry fine fuels. The elevated area surrounding both of these critical delineations has also been adjusted slightly mainly based on latest surface observations. No changes have been made to the critical area across parts of southern CA. Elevated to critical fire weather conditions are ongoing this morning across mainly the mountains/foothills of southern CA as weak to moderate offshore flow continues. A surface high across the Great Basin is forecast to continue weakening through the remainder of the period, which will result in a lessening surface pressure gradient and resultant offshore winds/critical fire weather threat by this evening. See the previous discussion below for more information. ..Gleason.. 10/25/2017 .PREV DISCUSSION... /ISSUED 1238 AM CDT Wed Oct 25 2017/ ...Synopsis... A strong anticyclone responsible for fire weather concerns in southern California in recent days will finally weaken dramatically today - partially due to substantial surface cyclogenesis in the Canadian Prairies and deepening of a surface trough in the central and northern Great Plains. This general pattern will result in lessening fire weather concerns in southern California (especially toward the afternoon and evening hours) along with widespread elevated to critical fire weather within a downslope regime across portions of the northern Rockies and adjacent Plains. ...Coastal Ranges of Southern California... With weakening high pressure across the Great Basin, the overall pressure gradient in the region will weaken substantially throughout the day. However, enough of a gradient will remain through midday in many areas for continued gusty northeasterly surface flow (gusting to 40+ mph in terrain favored areas) along with areas of very poor recovery and near-critical RH values persisting through the morning. Elevated/critical areas remain in place where winds will be strongest during the early morning hours amidst the critically dry airmass, although winds will be on the decrease throughout the day. ...Portions of the northern Plains and adjacent Rockies from Southeast Wyoming northward through much of Montana... Widespread westerly surface flow will strengthen throughout the day in response to dramatically strengthening mid-level flow (60-70 knots at 500 mb), vertical mixing of that higher momentum air to the surface, and a favorably oriented surface pressure gradient. 20-30 mph wind speeds will become common, with several areas gusting above 50 mph during peak heating hours - especially across central Montana where winds should be the strongest. The combination of warmer-than-average surface temperatures (in the 70s F), 8-15% minimum RH values, and dry fuels suggest potential for dangerous, rapidly spreading wildfires. Weaker surface flow will be common in portions of northeastern Wyoming and adjacent areas during the afternoon, although a fairly localized area of 20+ mph surface winds will develop for several hours near and west of the Laramie Range of Wyoming and adjacent areas of western Nebraska. Here, guidance suggest that RH values will fall below 15% for a few hours during the evening, and with dry fuels across the region, critical fire weather conditions are expected. Surrounding critical areas, stronger surface flow is not currently expected to coincide with critically low RH values sufficiently for any categorical upgrades. ...Please see www.spc.noaa.gov/fire for graphic product... Read more
Categories: Weather

Pages

Subscribe to Volunteer Mobile Emergency Response Unit -- rehabsector.org aggregator - Weather