Severe Storms

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 PM CDT Wed Jul 09 2025 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE CENTRAL GREAT PLAINS AND THE SOUTHEAST... ...SUMMARY... A corridor of scattered damaging winds is possible Thursday afternoon across a portion of the Southeast. Scattered severe thunderstorms are possible over parts of the central Great Plains, mainly from late afternoon through Thursday night. ...Central States... Much uncertainty plagues this forecast cycle with low predictability across guidance related to the development/evolution of multiple MCVs from D1. These MCVs will meander downstream of a low-amplitude shortwave trough progressing east from the northeast Great Basin into the central Great Plains on D2. Meanwhile, a positive-tilt shortwave trough should amplify from the Canadian Rockies into the southern Prairie Provinces/northern High Plains by early Friday. Have expanded level 1-MRGL risk eastward across the Upper MS Valley for potential diurnal intensification of convection surrounding remnant MCVs. While confidence is quite low in spatiotemporal details and the degree of convective coverage, there is adequate signal across guidance to warrant low-probability severe hail/wind hazards. Primary severe potential will likely commence towards peak heating across the central High Plains ahead of the aforementioned low-amplitude shortwave trough. Hot/deep-mixed thermodynamic profiles are expected from southwest/south-central NE southward, as the dryline reaches central KS. High-based convection in the post-dryline airmass will offer a threat of sporadic severe gusts. As convection impinges on a more buoyant airmass downstream, in tandem with a strengthening low-level jet from the southern High Plains towards eastern NE, an MCS should develop over NE in the evening. A downstream warm-advection arc will aid in sustaining this MCS eastward across a portion of the Mid-MO Valley. A swath of severe wind gusts with embedded severe hail will be possible Thursday night. Farther north in the northern Great Plains, latest signals are for broad, low-probability hail/wind threats. The timing of ascent and strengthening mid/upper-level flow appears delayed until late in the period ahead of the Canadian Rockies/northern High Plains trough. Convective coverage should remain isolated during the late afternoon to early evening along a weak surface front/trough. Modest deep-layer shear during this timeframe will modulate the overall threat as well. Greater convective potential should exist overnight but may largely remain behind the undercutting surface front as it sharpens southeastward. ...East... Weak deep-layer shear will be prevalent across much of the region on Thursday afternoon, south of modest mid-level westerlies across NY/New England associated with a low-amplitude shortwave trough over southeast Canada. Rich boundary-layer moisture will remain prevalent from the DE Valley southward. This will support a primary threat of wet microbursts producing erratic damaging winds. Have maintained a level 2-SLGT risk in a portion of the Southeast for the most probable corridor of widespread thunderstorms producing localized damaging winds. ..Grams.. 07/09/2025 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1157 AM CDT Wed Jul 09 2025 Valid 091700Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEVADA AND FAR WESTERN UTAH... ...Montana... A mid-level trough translating east across the Canada/U.S. border and subsequent breakdown of upper-level ridge over the Northern Rockies along with sufficient mid-level moisture/instability will aid in high-based thunderstorm development across the higher terrain of western MT, moving into eastern MT by evening. Fast east-northeastward thunderstorm trajectories on the order of 25-30 knots will limit rainfall (in addition to gusty/erratic outflow winds) over dry fuels, supporting an increased wildfire spread potential for portions of central and eastern MT where isolated dry thunderstorm highlights were added. Otherwise, previous forecast (see below) for additional fire weather threats across the Western U.S. remains on track with minimal changes. ..Williams.. 07/09/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Wed Jul 09 2025/ ...Synopsis... A compact midlevel trough will advance eastward across the northern Great Basin during the day. At the same time, a separate large-scale trough will move eastward across western Canada. ...Great Basin... Preceding the compact midlevel trough, moderate deep-layer southwesterly flow will overspread the Great Basin during peak heating. Deep boundary-layer mixing into this strengthening flow aloft will result in an expansive area of lower-teens RH and 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry fuels across the region, critical fire-weather conditions are expected from central NV into western UT (with elevated conditions surrounding this area across the Great Basin). ...Northwest... Large-scale ascent accompanying the compact midlevel trough will aid in isolated to widely scattered thunderstorm development over southeastern OR, southwestern ID, and far northeastern CA during the afternoon/evening hours. Deep inverted-V soundings and 0.5-0.7 inch PW will favor dry thunderstorms -- with a risk of lightning-induced ignitions and strong/erratic outflow winds. Additionally, strong westerly flow in the base of the large-scale trough moving across western Canada will persist across the Cascades. Despite slightly higher RH than previous days, strong downslope/westerly surface winds will favor elevated to locally critical fire-weather conditions in the Columbia Basin. ...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 1157 AM CDT Wed Jul 09 2025 Valid 091700Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEVADA AND FAR WESTERN UTAH... ...Montana... A mid-level trough translating east across the Canada/U.S. border and subsequent breakdown of upper-level ridge over the Northern Rockies along with sufficient mid-level moisture/instability will aid in high-based thunderstorm development across the higher terrain of western MT, moving into eastern MT by evening. Fast east-northeastward thunderstorm trajectories on the order of 25-30 knots will limit rainfall (in addition to gusty/erratic outflow winds) over dry fuels, supporting an increased wildfire spread potential for portions of central and eastern MT where isolated dry thunderstorm highlights were added. Otherwise, previous forecast (see below) for additional fire weather threats across the Western U.S. remains on track with minimal changes. ..Williams.. 07/09/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Wed Jul 09 2025/ ...Synopsis... A compact midlevel trough will advance eastward across the northern Great Basin during the day. At the same time, a separate large-scale trough will move eastward across western Canada. ...Great Basin... Preceding the compact midlevel trough, moderate deep-layer southwesterly flow will overspread the Great Basin during peak heating. Deep boundary-layer mixing into this strengthening flow aloft will result in an expansive area of lower-teens RH and 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry fuels across the region, critical fire-weather conditions are expected from central NV into western UT (with elevated conditions surrounding this area across the Great Basin). ...Northwest... Large-scale ascent accompanying the compact midlevel trough will aid in isolated to widely scattered thunderstorm development over southeastern OR, southwestern ID, and far northeastern CA during the afternoon/evening hours. Deep inverted-V soundings and 0.5-0.7 inch PW will favor dry thunderstorms -- with a risk of lightning-induced ignitions and strong/erratic outflow winds. Additionally, strong westerly flow in the base of the large-scale trough moving across western Canada will persist across the Cascades. Despite slightly higher RH than previous days, strong downslope/westerly surface winds will favor elevated to locally critical fire-weather conditions in the Columbia Basin. ...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 1157 AM CDT Wed Jul 09 2025 Valid 091700Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEVADA AND FAR WESTERN UTAH... ...Montana... A mid-level trough translating east across the Canada/U.S. border and subsequent breakdown of upper-level ridge over the Northern Rockies along with sufficient mid-level moisture/instability will aid in high-based thunderstorm development across the higher terrain of western MT, moving into eastern MT by evening. Fast east-northeastward thunderstorm trajectories on the order of 25-30 knots will limit rainfall (in addition to gusty/erratic outflow winds) over dry fuels, supporting an increased wildfire spread potential for portions of central and eastern MT where isolated dry thunderstorm highlights were added. Otherwise, previous forecast (see below) for additional fire weather threats across the Western U.S. remains on track with minimal changes. ..Williams.. 07/09/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Wed Jul 09 2025/ ...Synopsis... A compact midlevel trough will advance eastward across the northern Great Basin during the day. At the same time, a separate large-scale trough will move eastward across western Canada. ...Great Basin... Preceding the compact midlevel trough, moderate deep-layer southwesterly flow will overspread the Great Basin during peak heating. Deep boundary-layer mixing into this strengthening flow aloft will result in an expansive area of lower-teens RH and 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry fuels across the region, critical fire-weather conditions are expected from central NV into western UT (with elevated conditions surrounding this area across the Great Basin). ...Northwest... Large-scale ascent accompanying the compact midlevel trough will aid in isolated to widely scattered thunderstorm development over southeastern OR, southwestern ID, and far northeastern CA during the afternoon/evening hours. Deep inverted-V soundings and 0.5-0.7 inch PW will favor dry thunderstorms -- with a risk of lightning-induced ignitions and strong/erratic outflow winds. Additionally, strong westerly flow in the base of the large-scale trough moving across western Canada will persist across the Cascades. Despite slightly higher RH than previous days, strong downslope/westerly surface winds will favor elevated to locally critical fire-weather conditions in the Columbia Basin. ...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 1157 AM CDT Wed Jul 09 2025 Valid 091700Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEVADA AND FAR WESTERN UTAH... ...Montana... A mid-level trough translating east across the Canada/U.S. border and subsequent breakdown of upper-level ridge over the Northern Rockies along with sufficient mid-level moisture/instability will aid in high-based thunderstorm development across the higher terrain of western MT, moving into eastern MT by evening. Fast east-northeastward thunderstorm trajectories on the order of 25-30 knots will limit rainfall (in addition to gusty/erratic outflow winds) over dry fuels, supporting an increased wildfire spread potential for portions of central and eastern MT where isolated dry thunderstorm highlights were added. Otherwise, previous forecast (see below) for additional fire weather threats across the Western U.S. remains on track with minimal changes. ..Williams.. 07/09/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Wed Jul 09 2025/ ...Synopsis... A compact midlevel trough will advance eastward across the northern Great Basin during the day. At the same time, a separate large-scale trough will move eastward across western Canada. ...Great Basin... Preceding the compact midlevel trough, moderate deep-layer southwesterly flow will overspread the Great Basin during peak heating. Deep boundary-layer mixing into this strengthening flow aloft will result in an expansive area of lower-teens RH and 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry fuels across the region, critical fire-weather conditions are expected from central NV into western UT (with elevated conditions surrounding this area across the Great Basin). ...Northwest... Large-scale ascent accompanying the compact midlevel trough will aid in isolated to widely scattered thunderstorm development over southeastern OR, southwestern ID, and far northeastern CA during the afternoon/evening hours. Deep inverted-V soundings and 0.5-0.7 inch PW will favor dry thunderstorms -- with a risk of lightning-induced ignitions and strong/erratic outflow winds. Additionally, strong westerly flow in the base of the large-scale trough moving across western Canada will persist across the Cascades. Despite slightly higher RH than previous days, strong downslope/westerly surface winds will favor elevated to locally critical fire-weather conditions in the Columbia Basin. ...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 1157 AM CDT Wed Jul 09 2025 Valid 091700Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEVADA AND FAR WESTERN UTAH... ...Montana... A mid-level trough translating east across the Canada/U.S. border and subsequent breakdown of upper-level ridge over the Northern Rockies along with sufficient mid-level moisture/instability will aid in high-based thunderstorm development across the higher terrain of western MT, moving into eastern MT by evening. Fast east-northeastward thunderstorm trajectories on the order of 25-30 knots will limit rainfall (in addition to gusty/erratic outflow winds) over dry fuels, supporting an increased wildfire spread potential for portions of central and eastern MT where isolated dry thunderstorm highlights were added. Otherwise, previous forecast (see below) for additional fire weather threats across the Western U.S. remains on track with minimal changes. ..Williams.. 07/09/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Wed Jul 09 2025/ ...Synopsis... A compact midlevel trough will advance eastward across the northern Great Basin during the day. At the same time, a separate large-scale trough will move eastward across western Canada. ...Great Basin... Preceding the compact midlevel trough, moderate deep-layer southwesterly flow will overspread the Great Basin during peak heating. Deep boundary-layer mixing into this strengthening flow aloft will result in an expansive area of lower-teens RH and 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry fuels across the region, critical fire-weather conditions are expected from central NV into western UT (with elevated conditions surrounding this area across the Great Basin). ...Northwest... Large-scale ascent accompanying the compact midlevel trough will aid in isolated to widely scattered thunderstorm development over southeastern OR, southwestern ID, and far northeastern CA during the afternoon/evening hours. Deep inverted-V soundings and 0.5-0.7 inch PW will favor dry thunderstorms -- with a risk of lightning-induced ignitions and strong/erratic outflow winds. Additionally, strong westerly flow in the base of the large-scale trough moving across western Canada will persist across the Cascades. Despite slightly higher RH than previous days, strong downslope/westerly surface winds will favor elevated to locally critical fire-weather conditions in the Columbia Basin. ...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 1157 AM CDT Wed Jul 09 2025 Valid 091700Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEVADA AND FAR WESTERN UTAH... ...Montana... A mid-level trough translating east across the Canada/U.S. border and subsequent breakdown of upper-level ridge over the Northern Rockies along with sufficient mid-level moisture/instability will aid in high-based thunderstorm development across the higher terrain of western MT, moving into eastern MT by evening. Fast east-northeastward thunderstorm trajectories on the order of 25-30 knots will limit rainfall (in addition to gusty/erratic outflow winds) over dry fuels, supporting an increased wildfire spread potential for portions of central and eastern MT where isolated dry thunderstorm highlights were added. Otherwise, previous forecast (see below) for additional fire weather threats across the Western U.S. remains on track with minimal changes. ..Williams.. 07/09/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Wed Jul 09 2025/ ...Synopsis... A compact midlevel trough will advance eastward across the northern Great Basin during the day. At the same time, a separate large-scale trough will move eastward across western Canada. ...Great Basin... Preceding the compact midlevel trough, moderate deep-layer southwesterly flow will overspread the Great Basin during peak heating. Deep boundary-layer mixing into this strengthening flow aloft will result in an expansive area of lower-teens RH and 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry fuels across the region, critical fire-weather conditions are expected from central NV into western UT (with elevated conditions surrounding this area across the Great Basin). ...Northwest... Large-scale ascent accompanying the compact midlevel trough will aid in isolated to widely scattered thunderstorm development over southeastern OR, southwestern ID, and far northeastern CA during the afternoon/evening hours. Deep inverted-V soundings and 0.5-0.7 inch PW will favor dry thunderstorms -- with a risk of lightning-induced ignitions and strong/erratic outflow winds. Additionally, strong westerly flow in the base of the large-scale trough moving across western Canada will persist across the Cascades. Despite slightly higher RH than previous days, strong downslope/westerly surface winds will favor elevated to locally critical fire-weather conditions in the Columbia Basin. ...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 1157 AM CDT Wed Jul 09 2025 Valid 091700Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEVADA AND FAR WESTERN UTAH... ...Montana... A mid-level trough translating east across the Canada/U.S. border and subsequent breakdown of upper-level ridge over the Northern Rockies along with sufficient mid-level moisture/instability will aid in high-based thunderstorm development across the higher terrain of western MT, moving into eastern MT by evening. Fast east-northeastward thunderstorm trajectories on the order of 25-30 knots will limit rainfall (in addition to gusty/erratic outflow winds) over dry fuels, supporting an increased wildfire spread potential for portions of central and eastern MT where isolated dry thunderstorm highlights were added. Otherwise, previous forecast (see below) for additional fire weather threats across the Western U.S. remains on track with minimal changes. ..Williams.. 07/09/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Wed Jul 09 2025/ ...Synopsis... A compact midlevel trough will advance eastward across the northern Great Basin during the day. At the same time, a separate large-scale trough will move eastward across western Canada. ...Great Basin... Preceding the compact midlevel trough, moderate deep-layer southwesterly flow will overspread the Great Basin during peak heating. Deep boundary-layer mixing into this strengthening flow aloft will result in an expansive area of lower-teens RH and 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry fuels across the region, critical fire-weather conditions are expected from central NV into western UT (with elevated conditions surrounding this area across the Great Basin). ...Northwest... Large-scale ascent accompanying the compact midlevel trough will aid in isolated to widely scattered thunderstorm development over southeastern OR, southwestern ID, and far northeastern CA during the afternoon/evening hours. Deep inverted-V soundings and 0.5-0.7 inch PW will favor dry thunderstorms -- with a risk of lightning-induced ignitions and strong/erratic outflow winds. Additionally, strong westerly flow in the base of the large-scale trough moving across western Canada will persist across the Cascades. Despite slightly higher RH than previous days, strong downslope/westerly surface winds will favor elevated to locally critical fire-weather conditions in the Columbia Basin. ...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 1157 AM CDT Wed Jul 09 2025 Valid 091700Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEVADA AND FAR WESTERN UTAH... ...Montana... A mid-level trough translating east across the Canada/U.S. border and subsequent breakdown of upper-level ridge over the Northern Rockies along with sufficient mid-level moisture/instability will aid in high-based thunderstorm development across the higher terrain of western MT, moving into eastern MT by evening. Fast east-northeastward thunderstorm trajectories on the order of 25-30 knots will limit rainfall (in addition to gusty/erratic outflow winds) over dry fuels, supporting an increased wildfire spread potential for portions of central and eastern MT where isolated dry thunderstorm highlights were added. Otherwise, previous forecast (see below) for additional fire weather threats across the Western U.S. remains on track with minimal changes. ..Williams.. 07/09/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Wed Jul 09 2025/ ...Synopsis... A compact midlevel trough will advance eastward across the northern Great Basin during the day. At the same time, a separate large-scale trough will move eastward across western Canada. ...Great Basin... Preceding the compact midlevel trough, moderate deep-layer southwesterly flow will overspread the Great Basin during peak heating. Deep boundary-layer mixing into this strengthening flow aloft will result in an expansive area of lower-teens RH and 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry fuels across the region, critical fire-weather conditions are expected from central NV into western UT (with elevated conditions surrounding this area across the Great Basin). ...Northwest... Large-scale ascent accompanying the compact midlevel trough will aid in isolated to widely scattered thunderstorm development over southeastern OR, southwestern ID, and far northeastern CA during the afternoon/evening hours. Deep inverted-V soundings and 0.5-0.7 inch PW will favor dry thunderstorms -- with a risk of lightning-induced ignitions and strong/erratic outflow winds. Additionally, strong westerly flow in the base of the large-scale trough moving across western Canada will persist across the Cascades. Despite slightly higher RH than previous days, strong downslope/westerly surface winds will favor elevated to locally critical fire-weather conditions in the Columbia Basin. ...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 1157 AM CDT Wed Jul 09 2025 Valid 091700Z - 101200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEVADA AND FAR WESTERN UTAH... ...Montana... A mid-level trough translating east across the Canada/U.S. border and subsequent breakdown of upper-level ridge over the Northern Rockies along with sufficient mid-level moisture/instability will aid in high-based thunderstorm development across the higher terrain of western MT, moving into eastern MT by evening. Fast east-northeastward thunderstorm trajectories on the order of 25-30 knots will limit rainfall (in addition to gusty/erratic outflow winds) over dry fuels, supporting an increased wildfire spread potential for portions of central and eastern MT where isolated dry thunderstorm highlights were added. Otherwise, previous forecast (see below) for additional fire weather threats across the Western U.S. remains on track with minimal changes. ..Williams.. 07/09/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Wed Jul 09 2025/ ...Synopsis... A compact midlevel trough will advance eastward across the northern Great Basin during the day. At the same time, a separate large-scale trough will move eastward across western Canada. ...Great Basin... Preceding the compact midlevel trough, moderate deep-layer southwesterly flow will overspread the Great Basin during peak heating. Deep boundary-layer mixing into this strengthening flow aloft will result in an expansive area of lower-teens RH and 20-25 mph sustained west-southwesterly surface winds. Given increasingly dry fuels across the region, critical fire-weather conditions are expected from central NV into western UT (with elevated conditions surrounding this area across the Great Basin). ...Northwest... Large-scale ascent accompanying the compact midlevel trough will aid in isolated to widely scattered thunderstorm development over southeastern OR, southwestern ID, and far northeastern CA during the afternoon/evening hours. Deep inverted-V soundings and 0.5-0.7 inch PW will favor dry thunderstorms -- with a risk of lightning-induced ignitions and strong/erratic outflow winds. Additionally, strong westerly flow in the base of the large-scale trough moving across western Canada will persist across the Cascades. Despite slightly higher RH than previous days, strong downslope/westerly surface winds will favor elevated to locally critical fire-weather conditions in the Columbia Basin. ...Please see www.spc.noaa.gov/fire for graphic product... Read more