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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Mon Dec 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS SOUTH-CENTRAL/EAST TEXAS... ...SUMMARY... A few locally severe storms could occur across parts of central and East Texas on Tuesday. ...Synopsis... On Tuesday a progressive upper-level pattern will be present with a positively tilted mid-level trough advancing off the New England Coast, a mid-level trough amplifying across the southern Plains, and a stronger trough moving from off the California coast to the Southwest during the forecast period. Inland low-level moisture will result in some instability, adequate for thunderstorms across portions of the southern Plains. A few of these storms may be severe across central/east Texas. ...Central/East Texas... Thunderstorms will likely be ongoing at the beginning of the period within the warm air advection zone across eastern Oklahoma. South of this activity, isolated convection may be possible within a region of broad ascent associated with a 30 to 35 knot low-level jet. Instability and shear will likely be too weak for severe thunderstorms from this activity. However, by Tuesday afternoon/evening, continued moisture advection and some weak surface heating should result in greater instability along and south of the cold front/composite outflow across northeast Texas. In addition to the greater instability, forcing will increase ahead of the approaching trough and mid-level flow will strengthen. This will likely result in scattered convection amid weak to moderate instability and 30 to 35 knots of shear. Some transient supercell structures may be possible along and ahead of the cold front as it advances southeast through the afternoon and evening. While the low-level flow is forecast to be quite weak, particularly across southeast Texas where instability will be greatest, forecast hodographs do show significant clockwise curvature in the lowest 1 to 2 km. Therefore, a tornado cannot be ruled out, particularly with any stronger/longer-lived supercells which may develop. ...Northern California/Pacific Northwest... As a prominent upper-level trough and related frontal band moves inland, isolated thunderstorms will be possible across northern California coastal areas and the adjacent Central Valley on Tuesday morning with the frontal band and later in the day with post-frontal cellular convection as low/mid-level lapse rates steepen. A more limited/isolated thunderstorm potential will also exist across other parts of the coastal Pacific Northwest. ..Bentley.. 12/23/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Mon Dec 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS SOUTH-CENTRAL/EAST TEXAS... ...SUMMARY... A few locally severe storms could occur across parts of central and East Texas on Tuesday. ...Synopsis... On Tuesday a progressive upper-level pattern will be present with a positively tilted mid-level trough advancing off the New England Coast, a mid-level trough amplifying across the southern Plains, and a stronger trough moving from off the California coast to the Southwest during the forecast period. Inland low-level moisture will result in some instability, adequate for thunderstorms across portions of the southern Plains. A few of these storms may be severe across central/east Texas. ...Central/East Texas... Thunderstorms will likely be ongoing at the beginning of the period within the warm air advection zone across eastern Oklahoma. South of this activity, isolated convection may be possible within a region of broad ascent associated with a 30 to 35 knot low-level jet. Instability and shear will likely be too weak for severe thunderstorms from this activity. However, by Tuesday afternoon/evening, continued moisture advection and some weak surface heating should result in greater instability along and south of the cold front/composite outflow across northeast Texas. In addition to the greater instability, forcing will increase ahead of the approaching trough and mid-level flow will strengthen. This will likely result in scattered convection amid weak to moderate instability and 30 to 35 knots of shear. Some transient supercell structures may be possible along and ahead of the cold front as it advances southeast through the afternoon and evening. While the low-level flow is forecast to be quite weak, particularly across southeast Texas where instability will be greatest, forecast hodographs do show significant clockwise curvature in the lowest 1 to 2 km. Therefore, a tornado cannot be ruled out, particularly with any stronger/longer-lived supercells which may develop. ...Northern California/Pacific Northwest... As a prominent upper-level trough and related frontal band moves inland, isolated thunderstorms will be possible across northern California coastal areas and the adjacent Central Valley on Tuesday morning with the frontal band and later in the day with post-frontal cellular convection as low/mid-level lapse rates steepen. A more limited/isolated thunderstorm potential will also exist across other parts of the coastal Pacific Northwest. ..Bentley.. 12/23/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Mon Dec 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS SOUTH-CENTRAL/EAST TEXAS... ...SUMMARY... A few locally severe storms could occur across parts of central and East Texas on Tuesday. ...Synopsis... On Tuesday a progressive upper-level pattern will be present with a positively tilted mid-level trough advancing off the New England Coast, a mid-level trough amplifying across the southern Plains, and a stronger trough moving from off the California coast to the Southwest during the forecast period. Inland low-level moisture will result in some instability, adequate for thunderstorms across portions of the southern Plains. A few of these storms may be severe across central/east Texas. ...Central/East Texas... Thunderstorms will likely be ongoing at the beginning of the period within the warm air advection zone across eastern Oklahoma. South of this activity, isolated convection may be possible within a region of broad ascent associated with a 30 to 35 knot low-level jet. Instability and shear will likely be too weak for severe thunderstorms from this activity. However, by Tuesday afternoon/evening, continued moisture advection and some weak surface heating should result in greater instability along and south of the cold front/composite outflow across northeast Texas. In addition to the greater instability, forcing will increase ahead of the approaching trough and mid-level flow will strengthen. This will likely result in scattered convection amid weak to moderate instability and 30 to 35 knots of shear. Some transient supercell structures may be possible along and ahead of the cold front as it advances southeast through the afternoon and evening. While the low-level flow is forecast to be quite weak, particularly across southeast Texas where instability will be greatest, forecast hodographs do show significant clockwise curvature in the lowest 1 to 2 km. Therefore, a tornado cannot be ruled out, particularly with any stronger/longer-lived supercells which may develop. ...Northern California/Pacific Northwest... As a prominent upper-level trough and related frontal band moves inland, isolated thunderstorms will be possible across northern California coastal areas and the adjacent Central Valley on Tuesday morning with the frontal band and later in the day with post-frontal cellular convection as low/mid-level lapse rates steepen. A more limited/isolated thunderstorm potential will also exist across other parts of the coastal Pacific Northwest. ..Bentley.. 12/23/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1017 AM CST Mon Dec 23 2024 Valid 231630Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A modifying air mass is returning northward into TX from the western Gulf basin, and continued low-level warming/moistening will result in gradual destabilization. Modest amplification of a midlevel trough over the southern High Plains, in combination with an increasingly moist warm advection regime, will support the potential for a few elevated thunderstorms this evening into tonight across parts of OK/north TX. There is also a small chance for near-surface-based thunderstorms along a confluence zone from Matagorda Bay northward into the western parts of southeast TX. Otherwise, a midlevel trough over the eastern Pacific will approach northern CA late in the period, when weak destabilization could support sufficiently deep convection for isolated lightning flashes. Farther east, the potential for deep convection will increase through the period in association with air mass modification and weak cyclogenesis in the vicinity of the Gulf Stream. However, the potential for thunderstorms is expected to remain offshore. ..Thompson/Moore.. 12/23/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1017 AM CST Mon Dec 23 2024 Valid 231630Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A modifying air mass is returning northward into TX from the western Gulf basin, and continued low-level warming/moistening will result in gradual destabilization. Modest amplification of a midlevel trough over the southern High Plains, in combination with an increasingly moist warm advection regime, will support the potential for a few elevated thunderstorms this evening into tonight across parts of OK/north TX. There is also a small chance for near-surface-based thunderstorms along a confluence zone from Matagorda Bay northward into the western parts of southeast TX. Otherwise, a midlevel trough over the eastern Pacific will approach northern CA late in the period, when weak destabilization could support sufficiently deep convection for isolated lightning flashes. Farther east, the potential for deep convection will increase through the period in association with air mass modification and weak cyclogenesis in the vicinity of the Gulf Stream. However, the potential for thunderstorms is expected to remain offshore. ..Thompson/Moore.. 12/23/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1017 AM CST Mon Dec 23 2024 Valid 231630Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A modifying air mass is returning northward into TX from the western Gulf basin, and continued low-level warming/moistening will result in gradual destabilization. Modest amplification of a midlevel trough over the southern High Plains, in combination with an increasingly moist warm advection regime, will support the potential for a few elevated thunderstorms this evening into tonight across parts of OK/north TX. There is also a small chance for near-surface-based thunderstorms along a confluence zone from Matagorda Bay northward into the western parts of southeast TX. Otherwise, a midlevel trough over the eastern Pacific will approach northern CA late in the period, when weak destabilization could support sufficiently deep convection for isolated lightning flashes. Farther east, the potential for deep convection will increase through the period in association with air mass modification and weak cyclogenesis in the vicinity of the Gulf Stream. However, the potential for thunderstorms is expected to remain offshore. ..Thompson/Moore.. 12/23/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1017 AM CST Mon Dec 23 2024 Valid 231630Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A modifying air mass is returning northward into TX from the western Gulf basin, and continued low-level warming/moistening will result in gradual destabilization. Modest amplification of a midlevel trough over the southern High Plains, in combination with an increasingly moist warm advection regime, will support the potential for a few elevated thunderstorms this evening into tonight across parts of OK/north TX. There is also a small chance for near-surface-based thunderstorms along a confluence zone from Matagorda Bay northward into the western parts of southeast TX. Otherwise, a midlevel trough over the eastern Pacific will approach northern CA late in the period, when weak destabilization could support sufficiently deep convection for isolated lightning flashes. Farther east, the potential for deep convection will increase through the period in association with air mass modification and weak cyclogenesis in the vicinity of the Gulf Stream. However, the potential for thunderstorms is expected to remain offshore. ..Thompson/Moore.. 12/23/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1017 AM CST Mon Dec 23 2024 Valid 231630Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A modifying air mass is returning northward into TX from the western Gulf basin, and continued low-level warming/moistening will result in gradual destabilization. Modest amplification of a midlevel trough over the southern High Plains, in combination with an increasingly moist warm advection regime, will support the potential for a few elevated thunderstorms this evening into tonight across parts of OK/north TX. There is also a small chance for near-surface-based thunderstorms along a confluence zone from Matagorda Bay northward into the western parts of southeast TX. Otherwise, a midlevel trough over the eastern Pacific will approach northern CA late in the period, when weak destabilization could support sufficiently deep convection for isolated lightning flashes. Farther east, the potential for deep convection will increase through the period in association with air mass modification and weak cyclogenesis in the vicinity of the Gulf Stream. However, the potential for thunderstorms is expected to remain offshore. ..Thompson/Moore.. 12/23/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1009 AM CST Mon Dec 23 2024 Valid 231700Z - 241200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 12/23/2024 .PREV DISCUSSION... /ISSUED 0100 AM CST Mon Dec 23 2024/ ...Synopsis... Fire-weather concerns will be minimal today. Locally dry/breezy conditions are possible in the vicinity of a weak lee cyclone over the southern High Plains, though surface winds should remain too light for a fire-weather threat. ...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 1009 AM CST Mon Dec 23 2024 Valid 231700Z - 241200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 12/23/2024 .PREV DISCUSSION... /ISSUED 0100 AM CST Mon Dec 23 2024/ ...Synopsis... Fire-weather concerns will be minimal today. Locally dry/breezy conditions are possible in the vicinity of a weak lee cyclone over the southern High Plains, though surface winds should remain too light for a fire-weather threat. ...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 1009 AM CST Mon Dec 23 2024 Valid 231700Z - 241200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 12/23/2024 .PREV DISCUSSION... /ISSUED 0100 AM CST Mon Dec 23 2024/ ...Synopsis... Fire-weather concerns will be minimal today. Locally dry/breezy conditions are possible in the vicinity of a weak lee cyclone over the southern High Plains, though surface winds should remain too light for a fire-weather threat. ...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 1009 AM CST Mon Dec 23 2024 Valid 231700Z - 241200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 12/23/2024 .PREV DISCUSSION... /ISSUED 0100 AM CST Mon Dec 23 2024/ ...Synopsis... Fire-weather concerns will be minimal today. Locally dry/breezy conditions are possible in the vicinity of a weak lee cyclone over the southern High Plains, though surface winds should remain too light for a fire-weather threat. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sun Dec 22 18:05:02 UTC 2024.

MD 2274 CONCERNING FREEZING RAIN FOR NORTHWEST TO CENTRAL NORTH DAKOTA INTO FAR NORTHEAST MONTANA
Mesoscale Discussion 2274 NWS Storm Prediction Center Norman OK 0913 AM CST Sun Dec 22 2024 Areas affected...Northwest to central North Dakota into far northeast Montana Concerning...Freezing rain Valid 221513Z - 221915Z SUMMARY...Light to moderate freezing rain (with rates possibly as high as 0.1 inch/hour) is expected to begin across far northeast Montana and into northwest North Dakota by early afternoon. DISCUSSION...Regional radar mosaics show light to moderate precipitation overspreading much of eastern MT, gradually moving east into ND within the left-exit region of a modest mid-level jet. 12 UTC soundings from GGW and BIS show a pronounced 8-9 C warm nose between 900 to 850 mb with sub-freezing temperatures at the surface (including an impressive 22 C inversion on the BIS sounding). While some modulation of the low-level inversion is expected through early afternoon via wet-bulb cooling within the warm nose and downward mixing of warmer air near the surface, forecast guidance and recent surface obs suggest that most locations across northwest to central ND will maintain favorable low-level thermal profiles for freezing rain through much of the day. Live web cams from Williston and Dickinson, ND show little in the way of ongoing precipitation as of 15 UTC, suggesting that the initial wave of light precipitation currently moving over western ND is mainly saturating a dry 850-500 mb layer. This gradual saturation will promote steadier precipitation through early/mid-afternoon as additional showers migrate east from MT in tandem with the upper wave/jet. As such, the potential for freezing rain is expected to increase heading into the afternoon hours. Morning guidance suggests freezing rain rates up to 0.03 inch/hour are likely, but more aggressive solutions (notably the HRRR) hint that higher rates up to 0.1 inch/hour are possible (though not probable given relatively weak mesoscale forcing for ascent). ..Moore.. 12/22/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BIS...GGW... LAT...LON 48530222 47930087 47690052 47470038 47010035 46830046 46730079 46740107 46870167 47170261 47440340 47540373 47720412 48060434 48440428 48580419 48730381 48760310 48530222 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1116 AM CST Sun Dec 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Monday. A midlevel shortwave trough will amplify from the central Rockies to the south-central High Plains on Monday. A weak surface low will likely develop across Texas into southern Oklahoma, with a modest increase in low-level moisture across central/east Texas into southern Oklahoma in advance of a cold front moving southeastward across the southern High Plains. Increasing forcing for ascent and elevated moisture transport should lead to increasing elevated convection Monday night across north/northeast Texas into southeast Oklahoma and the ArkLaTex. While a mid-level capping inversion may tend to persist, updrafts should increasingly reach a sufficient depth/temperature late Monday night into early Tuesday for at least isolated thunderstorms. Severe thunderstorms are not currently expected given access to only weak elevated buoyancy. Isolated thunderstorms will also be possible late Monday night across the coastal Pacific Northwest and northern California as temperatures aloft cool with the approaching mid-level trough. ..Bentley.. 12/22/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1015 AM CST Sun Dec 22 2024 Valid 221700Z - 231200Z ...NO CRITICAL AREAS... ...Update... No changes are required for today's update. Increasing westerly surface winds are expected across the High Plains of NM, which could result in ~1 hour of localized elevated fire weather conditions there later this afternoon as RH falls into the low teens. Due to the limited duration of these conditions, however, an Elevated area is not warranted. ..Barnes.. 12/22/2024 .PREV DISCUSSION... /ISSUED 0141 AM CST Sun Dec 22 2024/ ...Synopsis... A shortwave trough and accompanying jet streak will cross the northern Rockies, while a related lee cyclone/trough briefly deepens over the central and southern Plains. As a result, locally dry/breezy conditions are possible over portions of the southern High Plains, though fire-weather concerns will be low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1003 AM CST Sun Dec 22 2024 Valid 221630Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States through tonight. ...Northern CA/Pacific Northwest coast through tonight... Lightning flashes have been observed this morning within a baroclinic band roughly 150 mi off the northern CA coast, in association with a midlevel shortwave trough that will move inland later today into tonight. The potential for isolated lightning flashes inland will begin this afternoon with elevated convection in the warm conveyor belt across northwest CA/southwest OR. Other isolated lightning flashes may also occur this evening into early tonight along the WA coast as steeper low-midlevel lapse rates and weak buoyancy spread inland. ..Thompson/Moore.. 12/22/2024 Read more

No watches are valid as of Sat Dec 21 17:55:02 UTC 2024.

No Mesoscale Discussions are in effect as of Sat Dec 21 17:55:02 UTC 2024.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1114 AM CST Sat Dec 21 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Sunday. ...Synopsis... Broad upper ridging over the central CONUS will begin to break down through the day Sunday as a shortwave trough, currently moving into the Pacific Northwest, traverses the Rockies. A broad surface high building over the eastern CONUS will maintain cool/dry conditions. Weak lee troughing over the High Plains will promote gradual moisture return along the TX Gulf coast, but moisture quality/depth and poor mid-level lapse rates will be insufficient to support deep convection. A pronounced upper wave noted over the northern Pacific in water-vapor imagery will approach the West Coast through the period. Latest forecast guidance suggests sufficient destabilization for a few lightning flashes is possible as colder temperatures aloft and broad scale ascent overspread the region. The potential for severe convection remains low given very limited buoyancy. ..Moore.. 12/21/2024 Read more