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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1246 AM CDT Sun Oct 13 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM CENTRAL/EASTERN WV TO MIDDLE/EASTERN TN... ...SUMMARY... Strong to locally severe thunderstorms are possible, mainly this evening, across parts of the central/southern Appalachians and Tennessee Valley. Isolated wind damage and marginally severe hail are the expected hazards. ...Central/southern Appalachians and the TN Valley... A vigorous shortwave impulse will dig through the basal portion of a mid/upper trough and yield amplification of this trough southward across the Great Lakes through Monday morning. Appreciable mid-level height falls will overspread the central/southern Appalachians into the TN Valley, mainly during the evening and overnight. A leading and weaker mid-level impulse should yield the primary surface cyclone moving east across PA during the afternoon to early evening. A surface cold front will extend southwest of this low into the TN Valley. Convective development along the front appears likely to be delayed until early evening, as the strengthening large-scale ascent aids in increasing low-level convergence along the boundary amid pervasive veered flow within the warm sector. Surface dew points should largely range from the mid 50s in WV to a narrow corridor of low 60s in Middle TN, yielding a plume of modest buoyancy between 500-1500 J/kg amid initially steep mid-level lapse rates. Guidance differs greatly in the degree of storm coverage, from nil to scattered, perhaps in response to the ascent strengthening after peak diurnal heating. The strongest 700-mb westerlies, in excess of 50 kts, should be confined northeast of TN. Forecast hodographs above this level appear small, owing to weakening winds with height as fast mid/upper flow lags to the north-northwest. This suggests supercell structures may struggle to develop/be sustained. But the strong 700-mb flow could support localized damaging winds in any multicell clusters. Farther southwest, somewhat greater buoyancy could foster small to marginally severe hail as well. The overall severe threat appears likely to remain marginal and isolated. ..Grams/Halbert.. 10/13/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1246 AM CDT Sun Oct 13 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM CENTRAL/EASTERN WV TO MIDDLE/EASTERN TN... ...SUMMARY... Strong to locally severe thunderstorms are possible, mainly this evening, across parts of the central/southern Appalachians and Tennessee Valley. Isolated wind damage and marginally severe hail are the expected hazards. ...Central/southern Appalachians and the TN Valley... A vigorous shortwave impulse will dig through the basal portion of a mid/upper trough and yield amplification of this trough southward across the Great Lakes through Monday morning. Appreciable mid-level height falls will overspread the central/southern Appalachians into the TN Valley, mainly during the evening and overnight. A leading and weaker mid-level impulse should yield the primary surface cyclone moving east across PA during the afternoon to early evening. A surface cold front will extend southwest of this low into the TN Valley. Convective development along the front appears likely to be delayed until early evening, as the strengthening large-scale ascent aids in increasing low-level convergence along the boundary amid pervasive veered flow within the warm sector. Surface dew points should largely range from the mid 50s in WV to a narrow corridor of low 60s in Middle TN, yielding a plume of modest buoyancy between 500-1500 J/kg amid initially steep mid-level lapse rates. Guidance differs greatly in the degree of storm coverage, from nil to scattered, perhaps in response to the ascent strengthening after peak diurnal heating. The strongest 700-mb westerlies, in excess of 50 kts, should be confined northeast of TN. Forecast hodographs above this level appear small, owing to weakening winds with height as fast mid/upper flow lags to the north-northwest. This suggests supercell structures may struggle to develop/be sustained. But the strong 700-mb flow could support localized damaging winds in any multicell clusters. Farther southwest, somewhat greater buoyancy could foster small to marginally severe hail as well. The overall severe threat appears likely to remain marginal and isolated. ..Grams/Halbert.. 10/13/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sun Oct 13 2024 Valid 141200Z - 151200Z ...NO CRITICAL AREAS... ...Synopsis... Dry and windy conditions are expected across far southern Arizona and portions of eastern New Mexico. However, current fuels guidance does not suggest significant vulnerability to wildfire ignition and spread at this time, precluding highlights. Some forecast guidance, mainly the GFS, suggest dry/windy southerly flow across western Texas on Monday, but remains an outlier relative to other models. Given the uncertainty and lack of Elevated/Critical conditions over receptive fuels, no fire-weather highlights are forecast. ..Halbert.. 10/13/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sun Oct 13 2024 Valid 141200Z - 151200Z ...NO CRITICAL AREAS... ...Synopsis... Dry and windy conditions are expected across far southern Arizona and portions of eastern New Mexico. However, current fuels guidance does not suggest significant vulnerability to wildfire ignition and spread at this time, precluding highlights. Some forecast guidance, mainly the GFS, suggest dry/windy southerly flow across western Texas on Monday, but remains an outlier relative to other models. Given the uncertainty and lack of Elevated/Critical conditions over receptive fuels, no fire-weather highlights are forecast. ..Halbert.. 10/13/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sun Oct 13 2024 Valid 131200Z - 141200Z ...Synopsis... A mid-level shortwave trough will transition to a closed low over the northern Great Basin, providing some enhancement to the mid-level flow and stronger southerly surface winds over portions of northwestern Arizona into southern Utah. Dry/breezy post-frontal flow in Oklahoma will also support Elevated fire-weather concerns. ...Northwest Arizona into Utah... The forecast has trended a little less dry, with relative humidity values between 15-20% and 15-20 MPH winds. The strongest winds (approaching 20 MPH sustained) will be confined to northwest Arizona, where ERC values are on the lower end at the 80th annual percentile and relative humidity is closer to 20%. Further north in Utah, fuels vary between the 90th and 95th annual percentiles and are colocated with <15% relative humidity values, but confidence in winds exceeding sustained 15 MPH is lower. Given the overall spread of moisture, wind speeds, and fuel percentiles over the area, Elevated highlights have been maintained with no introduction of Critical areas. ...Oklahoma... Forecast guidance has come into better agreement for 15-20% relative humidity and 15 MPH winds during the afternoon as a cold front moves southward across Oklahoma. Fuels guidance shows ERC values at or exceeding the 98th annual percentile, supporting both wildfire ignition and spread. ..Halbert.. 10/13/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sun Oct 13 2024 Valid 131200Z - 141200Z ...Synopsis... A mid-level shortwave trough will transition to a closed low over the northern Great Basin, providing some enhancement to the mid-level flow and stronger southerly surface winds over portions of northwestern Arizona into southern Utah. Dry/breezy post-frontal flow in Oklahoma will also support Elevated fire-weather concerns. ...Northwest Arizona into Utah... The forecast has trended a little less dry, with relative humidity values between 15-20% and 15-20 MPH winds. The strongest winds (approaching 20 MPH sustained) will be confined to northwest Arizona, where ERC values are on the lower end at the 80th annual percentile and relative humidity is closer to 20%. Further north in Utah, fuels vary between the 90th and 95th annual percentiles and are colocated with <15% relative humidity values, but confidence in winds exceeding sustained 15 MPH is lower. Given the overall spread of moisture, wind speeds, and fuel percentiles over the area, Elevated highlights have been maintained with no introduction of Critical areas. ...Oklahoma... Forecast guidance has come into better agreement for 15-20% relative humidity and 15 MPH winds during the afternoon as a cold front moves southward across Oklahoma. Fuels guidance shows ERC values at or exceeding the 98th annual percentile, supporting both wildfire ignition and spread. ..Halbert.. 10/13/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 130503
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Sat Oct 12 2024

For the eastern North Pacific...east of 140 degrees west longitude:

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Beven

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sat Oct 12 2024 Valid 131200Z - 141200Z ...Synopsis... A mid-level shortwave trough will transition to a closed low over the northern Great Basin on Sunday, providing some enhancement to the mid-level flow and stronger southerly winds over portions of northwestern Arizona into southern Utah. Dry/breezy pre-frontal flow in Texas and post-frontal flow in Oklahoma may result in Elevated fire-weather conditions as well. ...Northwest Arizona into Utah... 15-20 MPH winds and 10-15% relative humidity values are expected as daytime heating and boundary-layer mixing occurs during the afternoon, with some areas seeing locally critical conditions where topography supports enhanced surface winds. These conditions will overspread fuels modestly to very receptive to wildfire ignition and spread, with ERC values between the 80th and 95th annual percentiles. ...Central Texas... Portions of central Texas may see Elevated fire-weather conditions on Sunday, where warm/dry southwesterly flow ahead of a southward-moving cold front will support at least 15 MPH winds with boundary-layer relative humidity values between 10% and 20%. However, these conditions don't currently overlap with especially receptive fuels, and there is still uncertainty in the surface wind speeds reaching sustained Elevated criteria. ...Oklahoma... Much of Oklahoma could also experience some Elevated fire-weather conditions in a dry and breezy post-frontal airmass. However, ensemble guidance indicates spread/uncertainty in both boundary-layer relative humidity and wind speeds supporting wildfire spread, and recent wetting rainfall has lessened fuel receptiveness in portions of Central Oklahoma. Still, much of the fuels surrounding the areas recently rained on have ERC values exceeding the 95th annual percentile. If future forecast guidance comes into better agreement about the meteorological conditions, Elevated highlights may be warranted. ..Halbert.. 10/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No Mesoscale Discussions are in effect as of Sat Oct 12 06:00:02 UTC 2024.

No watches are valid as of Sat Oct 12 06:00:02 UTC 2024.

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Sat Oct 12 2024 Valid 121200Z - 131200Z ...Synopsis... A mid-level trough will move into the Pacific Northwest, bringing modest westerly flow across the Great Basin. East of the Rockies, the mid-level flow is largely west-northwesterly owing to a mid-level jet core moving southeastward out of the Canadian Prairie into the northern Great Plains. These flow features will provide synoptic support for three separate Elevated fire-weather highlights: One that extends from northwestern Arizona into southern and central Utah (as well as portions of far eastern Nevada), another extending from South Dakota into far northwest Kansas, and lastly, a small area extending from the Permian Basin into western North Texas. ...Northwest Arizona into Utah... Daytime heating (and subsequent boundary-layer mixing) will result in 15 MPH winds (gusting to 20 MPH) and relative humidity values of 10-15%, overlapping with ERC fuels varying between the 80th and 95th annual percentiles. Locally critical conditions will be possible where topography supports enhanced surface winds. ...South Dakota into Northwest Kansas... Dry boundary-layer relative humidity of 15-20% and wind speeds of 15-20 MPH are expected in a post-frontal airmass progressing southward across the Northern and Central Great Plains. These conditions will overlap with ERC values at or exceeding the annual 98th percentiles, supporting wildfire ignition and spread. The forecast has trended towards drier and windier in portions of Nebraska and northwest Kansas, but the current forecast calls for conditions to remain below the criteria for Critical highlights at this time. ...West Texas... Ahead of the southward-moving cold front, warm/dry southwesterly flow is expected across much of West Texas. Recent forecast guidance has increased confidence in 15-20 MPH winds and 10-15% relative humidity values. However, the fuel receptiveness to wildfire spread is relatively modest, especially where recent rainfall has occurred in western North Texas. Still, a narrow corridor of overlap between these meteorological conditions and 80th-90th ERC annual percentile fuels exists, warranting the introduction of Elevated highlights. ..Halbert.. 10/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1151 PM CDT Fri Oct 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE SUNDAY AFTERNOON AND EVENING ACROSS MUCH OF WEST VIRGINIA...PARTS OF EASTERN KENTUCKY...SOUTHWESTERN VIRGINIA AND ADJACENT PORTIONS OF SOUTHERN OHIO...SOUTHWESTERN PENNSYLVANIA AND NORTHEASTERN TENNESSEE... ...SUMMARY... Strong thunderstorms may develop in a corridor across West Virginia, and perhaps into portions of eastern Kentucky and southwestern Virginia, late Sunday afternoon and evening. Some may be accompanied by small to marginally severe hail and potentially damaging wind gusts. ...Synopsis... Mid/upper flow across the northern mid-latitudes of the Pacific into North America will remain amplified through this period, with further amplification of large-scale troughing forecast across the Upper Midwest and Great Lakes into the Ohio Valley. Models indicate at least of couple of vigorous short wave perturbations digging within this troughing, one of which may contribute to modest surface cyclogenesis along a frontal zone across the Ohio Valley into the Northeast by late Sunday night. In lower latitudes, a residual mid-level shear axis across the central Gulf of Mexico and Florida Peninsula will generally demarcate the northern periphery of higher moisture content air. However, a continued gradual moistening of the boundary layer ahead of the interior U.S. front may contribute to a corridor of modest destabilization across parts of the Ohio/Tennessee Valleys into the western slopes of the Appalachians by late Sunday afternoon. ...West Virginia into eastern Kentucky/southwest Virginia... There remains variability among the models concerning the evolution of surface cyclogenesis across the Ohio Valley into the Northeast Sunday through Sunday night. However, there still appears a general consensus that a moistening, but well-mixed, boundary layer will become characterized by CAPE on the order of 500-1000 J/kg by late Sunday afternoon, within at least a narrow pre-frontal corridor across Tennessee/Kentucky into West Virginia. It appears that peak destabilization will coincide with strengthening westerly deep-layer wind fields, including to 50+ kt in the 700-500 mb layer. Forcing for ascent in advance of stronger mid-level height falls, which may not begin overspreading the region until after dark, remains more unclear. However, a developing pre-frontal low-level upslope flow component may aid thunderstorm initiation across parts of West Virginia, and perhaps into eastern Kentucky and southwestern Virginia by early Sunday evening. If this occurs, the environment probably will be conducive to a few stronger storms posing a risk for hail and potentially damaging wind gusts. ..Kerr.. 10/12/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1151 PM CDT Fri Oct 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE SUNDAY AFTERNOON AND EVENING ACROSS MUCH OF WEST VIRGINIA...PARTS OF EASTERN KENTUCKY...SOUTHWESTERN VIRGINIA AND ADJACENT PORTIONS OF SOUTHERN OHIO...SOUTHWESTERN PENNSYLVANIA AND NORTHEASTERN TENNESSEE... ...SUMMARY... Strong thunderstorms may develop in a corridor across West Virginia, and perhaps into portions of eastern Kentucky and southwestern Virginia, late Sunday afternoon and evening. Some may be accompanied by small to marginally severe hail and potentially damaging wind gusts. ...Synopsis... Mid/upper flow across the northern mid-latitudes of the Pacific into North America will remain amplified through this period, with further amplification of large-scale troughing forecast across the Upper Midwest and Great Lakes into the Ohio Valley. Models indicate at least of couple of vigorous short wave perturbations digging within this troughing, one of which may contribute to modest surface cyclogenesis along a frontal zone across the Ohio Valley into the Northeast by late Sunday night. In lower latitudes, a residual mid-level shear axis across the central Gulf of Mexico and Florida Peninsula will generally demarcate the northern periphery of higher moisture content air. However, a continued gradual moistening of the boundary layer ahead of the interior U.S. front may contribute to a corridor of modest destabilization across parts of the Ohio/Tennessee Valleys into the western slopes of the Appalachians by late Sunday afternoon. ...West Virginia into eastern Kentucky/southwest Virginia... There remains variability among the models concerning the evolution of surface cyclogenesis across the Ohio Valley into the Northeast Sunday through Sunday night. However, there still appears a general consensus that a moistening, but well-mixed, boundary layer will become characterized by CAPE on the order of 500-1000 J/kg by late Sunday afternoon, within at least a narrow pre-frontal corridor across Tennessee/Kentucky into West Virginia. It appears that peak destabilization will coincide with strengthening westerly deep-layer wind fields, including to 50+ kt in the 700-500 mb layer. Forcing for ascent in advance of stronger mid-level height falls, which may not begin overspreading the region until after dark, remains more unclear. However, a developing pre-frontal low-level upslope flow component may aid thunderstorm initiation across parts of West Virginia, and perhaps into eastern Kentucky and southwestern Virginia by early Sunday evening. If this occurs, the environment probably will be conducive to a few stronger storms posing a risk for hail and potentially damaging wind gusts. ..Kerr.. 10/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1225 AM CDT Sat Oct 12 2024 Valid 121200Z - 131200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe-thunderstorm threat appears low today. ...Discussion... A highly amplified flow field will gradually evolve across the northeastern Pacific and across Canada today and tonight. Some of this amplification will manifest as far south as the Great Lakes, as an energetic short-wave trough digs southeastward across the Canadian Prairie through the period. As this trough digs, weak surface frontal-wave development is expected along the pre-existing baroclinic zone expected to extend westward across the Midwest states at the start of the period. The low is forecast to evolve across the northwestern Missouri area initially, and then shift gradually eastward with time, reaching the western Ohio vicinity late. As the low progresses eastward, a cold frontal surge southward across the central Plains is expected -- reaching the Ozarks/Oklahoma/the Texas South Plains area by Sunday morning. Along with showers and a few thunderstorms that may evolve over southern Florida, elevated evening/overnight storms are expected to develop over the southern Upper Great Lakes region. This convection is expected to shift eastward across the Lower Lakes/Upper Ohio Valley area with time. While small hail may occur with the stronger storms, CAPE appears likely to remain insufficient to support severe-caliber hailstones. ..Goss/Halbert.. 10/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1225 AM CDT Sat Oct 12 2024 Valid 121200Z - 131200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe-thunderstorm threat appears low today. ...Discussion... A highly amplified flow field will gradually evolve across the northeastern Pacific and across Canada today and tonight. Some of this amplification will manifest as far south as the Great Lakes, as an energetic short-wave trough digs southeastward across the Canadian Prairie through the period. As this trough digs, weak surface frontal-wave development is expected along the pre-existing baroclinic zone expected to extend westward across the Midwest states at the start of the period. The low is forecast to evolve across the northwestern Missouri area initially, and then shift gradually eastward with time, reaching the western Ohio vicinity late. As the low progresses eastward, a cold frontal surge southward across the central Plains is expected -- reaching the Ozarks/Oklahoma/the Texas South Plains area by Sunday morning. Along with showers and a few thunderstorms that may evolve over southern Florida, elevated evening/overnight storms are expected to develop over the southern Upper Great Lakes region. This convection is expected to shift eastward across the Lower Lakes/Upper Ohio Valley area with time. While small hail may occur with the stronger storms, CAPE appears likely to remain insufficient to support severe-caliber hailstones. ..Goss/Halbert.. 10/12/2024 Read more

000
ABPZ20 KNHC 120523
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Fri Oct 11 2024

For the eastern North Pacific...east of 140 degrees west longitude:

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Cangialosi

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 PM CDT Fri Oct 11 2024 Valid 120100Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential will remain low today. ...Discussion... A short-wave trough continues moving southeastward across Ontario and the Upper Great Lakes, and will shift into Quebec -- and across the Lower Great Lakes into New England -- through the rest of the period. Showers are ongoing across parts of Quebec, Ontario, and eastern Lower Michigan, with a few thunderstorms embedded across the Ottawa Valley area. As this area of convection continues moving southeastward, sporadic lightning flashes may spread into the Lower Great Lakes region and western New England overnight. Elsewhere, convection remains nil across southern Florida and the Keys, and lightning has not been observed with convection off the California coast. As such, risk for lightning appears too limited to warrant continuation of these thunder areas from prior outlooks. ..Goss.. 10/12/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 PM CDT Fri Oct 11 2024 Valid 120100Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential will remain low today. ...Discussion... A short-wave trough continues moving southeastward across Ontario and the Upper Great Lakes, and will shift into Quebec -- and across the Lower Great Lakes into New England -- through the rest of the period. Showers are ongoing across parts of Quebec, Ontario, and eastern Lower Michigan, with a few thunderstorms embedded across the Ottawa Valley area. As this area of convection continues moving southeastward, sporadic lightning flashes may spread into the Lower Great Lakes region and western New England overnight. Elsewhere, convection remains nil across southern Florida and the Keys, and lightning has not been observed with convection off the California coast. As such, risk for lightning appears too limited to warrant continuation of these thunder areas from prior outlooks. ..Goss.. 10/12/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 PM CDT Fri Oct 11 2024 Valid 120100Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential will remain low today. ...Discussion... A short-wave trough continues moving southeastward across Ontario and the Upper Great Lakes, and will shift into Quebec -- and across the Lower Great Lakes into New England -- through the rest of the period. Showers are ongoing across parts of Quebec, Ontario, and eastern Lower Michigan, with a few thunderstorms embedded across the Ottawa Valley area. As this area of convection continues moving southeastward, sporadic lightning flashes may spread into the Lower Great Lakes region and western New England overnight. Elsewhere, convection remains nil across southern Florida and the Keys, and lightning has not been observed with convection off the California coast. As such, risk for lightning appears too limited to warrant continuation of these thunder areas from prior outlooks. ..Goss.. 10/12/2024 Read more

000
ABPZ20 KNHC 112326
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Fri Oct 11 2024

For the eastern North Pacific...east of 140 degrees west longitude:

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Kelly