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No watches are valid as of Wed Mar 15 21:20:02 UTC 2023.

No Mesoscale Discussions are in effect as of Wed Mar 15 21:20:02 UTC 2023.

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0238 PM CDT Wed Mar 15 2023 Valid 161200Z - 171200Z No changes were required to the Day 2 Fire Weather Outlook. See previous discussion below. ..Thornton.. 03/15/2023 .PREV DISCUSSION... /ISSUED 0106 AM CDT Wed Mar 15 2023/ ...Synopsis... Mid-level winds across the Trans-Pecos into parts of the southern High Plains will increase on Thursday as a shortwave trough ejects into the region. A surface low will track from the central Plains into the Upper Midwest. Attendant to the low, a cold front will sweep southward into the southern Plains. Ahead of the cold front, westerly winds of 15-25 mph are possible. RH will again be marginal for most areas. Within the Big Bend region, RH of around 20% will be possible. This is the most likely area for elevated fire weather. Farther north, near the cold front, RH may briefly reduce below critical levels. This will be dependent on the speed of the front and how much heating can occur just ahead of it. However, concerns should remain short-lived as RH will rapidly rise behind the boundary. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0231 PM CDT Wed Mar 15 2023 Valid 152000Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE LOWER COLORADO VALLEY INTO CENTRAL ARIZONA... ...SUMMARY... A couple of strong thunderstorms may impact parts of the lower Colorado Valley through south central Arizona late this afternoon into tonight, accompanied by at least some risk for severe weather. Ascent and cooling aloft with the upper trough over the Southwest may result in clusters of storms producing marginal hail from the Las Vegas area toward Phoenix. The threat may initialize around 21Z over the southern California deserts and spread into Arizona after 00Z. MUCAPE may exceed 500 J/kg, with cold profiles aloft and lengthy hodographs favoring hail production. Locally strong wind gusts cannot be ruled out as well especially across western areas where low-level lapse rates will be steepest late in the day. ..Jewell.. 03/15/2023 .PREV DISCUSSION... /ISSUED 1115 AM CDT Wed Mar 15 2023/ ...Synopsis... The northern branch of the prevailing split flow is undergoing substantive amplification across the northern mid-latitude Pacific into western North America. This includes building mid-level ridging across the Pacific Northwest into the Canadian Yukon and Northwest Territories, downstream of a significant digging trough. Less prominent mid-level troughing to the east is forecast to dig across the northern Rockies, perhaps increasingly in phase with a lower amplitude southern branch perturbation migrating inland of the southern Pacific coast into the southern Rockies by late tonight. Coinciding with these developments, a cold front appears likely to advance southward through much of the Great Basin, and to the lee of the Rockies, through much of the northern into central Great Plains. At the same time, expansive cold surface ridging, now present across much of the eastern U.S. (as far southwest as the northwestern Gulf coast and southeastern Great Plains), likely will be slow to lose influence, in the wake of amplified mid-level troughing and an associated surface cyclone slowly progressing away from the Atlantic Seaboard. A moistening southerly return flow may continue to develop around the western periphery of the prominent Eastern surface ridging, but mostly above a residual near-surface stable layer across eastern Texas into the Ozark Plateau/lower Missouri Valley. Closer to the modest surface troughing across the Texas South Plains and northwest Texas into western Oklahoma, the better boundary-layer based moisture return likely will remain capped by warm layers aloft. ...Southwest... Widespread cloud cover and light precipitation is currently overspreading much of the lower Colorado Valley and Plateau vicinity, in advance of the southern branch perturbation. However, by this afternoon, it does appear that at least the mid/high-level cloudiness will quickly spread east of the lower Colorado Valley vicinity, where boundary-layer dewpoints are in the mid 50s. With at least some insolation, it appears increasingly likely that the lingering moisture will support mixed-layer CAPE on the order of 250-500 J/kg, as mid-level cooling (500 mb temps to around/below -20 C) within the left exit region of an approaching jet streak (50-70+ kt at 500 mb) overspreads the lower Colorado Valley toward 16/00z. This environment should be conducive to thunderstorms capable of producing small hail and gusty winds, with the evolution of a few supercell structures accompanied by marginally severe hail/wind possible. Stronger storms may eventually focus within south-southwesterly low-level upslope flow into the Mogollon Rim vicinity, perhaps as far east as the Greater Phoenix vicinity by mid to late evening. Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1200 PM CDT Wed Mar 15 2023 Valid 161200Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF NORTHEAST TEXAS...SOUTHERN OKLAHOMA AND INTO THE ARKLATEX... ...SUMMARY... Scattered severe thunderstorms capable of producing large hail, damaging winds, and a few tornadoes appear likely Thursday afternoon and evening across parts of the southern Plains. Some of the hail could be very large over south-central Oklahoma and north-central Texas. ...Synopsis... A low-amplitude shortwave trough will move quickly east across the South Plains on Thursday, into the Ozarks during the evening and to the OH Valley by 12Z Friday. This wave will provide height falls over a broad region with midlevel winds increasing to 70 kt, enhancing shear. A northern-stream trough will also move toward the Upper MS Valley, with a tight midlevel temperature gradient and rapid cooling expected. At the surface, low pressure will exist over southern KS Thursday morning, with a cold front moving rapidly southeast to a Green Bay WI to Dallas TX line by 00Z Friday. A warm front will extend southeastward from the KS low across eastern OK and TX to start the day, moving north across the Arklatex by 00Z and into southwest AR by evening. Strengthening southerly winds will aid moisture return across the warm sector, with 60 F dewpoints meeting the front over southern OK, and mid 60s F over much of east/northeast TX and perhaps to the Arklatex by around 00Z. Surface pressures will increase ahead of the cold front over the Southern Plains into the lower MS Valley through the period as the cold air undercuts the warm sector and primary low rapidly deepens over the upper Great Lakes. Even so, the combination of destabilization over the southern Plains, strengthening shear and lift along the cold and warm fronts will likely lead to swaths of severe storms beginning Thursday afternoon, mainly from southern OK into northeast TX and toward the Arklatex and Sabine River. ...OK and TX Late afternoon through early evening... As the cold front pushes south, storms are expected to form by 20Z over central and southern OK, with additional activity building south and translating east across much of North TX through 00Z. Storms forming near the low and riding along the warm front into southeast OK will have tornado potential as given effective SRH over 300 m2/s2. Storms farther southwest toward the Red River and into TX may produce very large hail due to better lapse rates and instability. With time, the front will undercut the activity, with wind damage along with elevated hail expected. Farther south along the front into central/eastern TX, the front will continue to push rapidly south overnight, with increasing storm coverage. Ample instability will interact with the front, with parallel deep-layer shear vectors and weakening winds in the low levels. Hail appears to be the main threat as the storms become undercut by the cold air, but a narrow zone of damaging wind potential could materialize should storms propagate fast enough to keep up with the front. The cells over southern OK and North TX prior to 00Z in particularly may produce damaging hail and a tornado or two before the front undercuts the activity. Any cells or bows that can propagate with a strong eastward component may reside along the boundary longer, enhancing both severe wind and tornado threat. Another area of potential will be over northeast TX ahead of the cold front during the afternoon and evening. Initially, these storms will be elevated as they move into AR, beneath a 50+ kt low-level jet. As the warmer air moves into this region, a few supercells will be possible with tornado, hail and wind potential. Instability is forecast to be limited farther east, but strong shear may allow a few severe storms to produce damage into northern LA and southern AR. ...Lower MS Valley overnight... Height falls as well as increasing winds aloft will overspread the region despite the main wave passing well to the north. Winds around 850 mb will still be over 40 kt, veering to west/southwesterly. This will essentially parallel the cold front which will push into MS and central LA by 12Z Friday. Given the cool/dry air mass initially in place, temperatures will likely be limited to the 60s F from afternoon into the overnight. The moistening boundary layer will maintain warmth overnight, but MUCAPE values are forecast to be very low. Many models indicate zero SBCAPE north of about I-10. Nonetheless, strong lift along the front will result in showers and thunderstorms, and some of this activity could potentially produce strong wind gusts given flow magnitudes just off the surface. ..Jewell.. 03/15/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1154 AM CDT Wed Mar 15 2023 Valid 151700Z - 161200Z No changes were made to the Southern/Central High Plains Elevated delineation for the Day 1 Fire Weather Outlook. See previous discussion below for more information. Elevated fire weather conditions will be possible along the East Coast in eastern North Carolina, Virginia, and southern Delaware. Relative humidity may drop as low as 20-25 percent briefly this afternoon with breezy northwesterly winds. Model consensus is spread on exactly how low relative humidity will drop. Ensemble guidance from the HREF shows around 30-40 percent conditional probability of Elevated conditions for a couple of hours. Given low confidence on afternoon relative humidity and marginal fuels, have opted to just include mention for potential Elevated conditions with no areas included. ..Thornton.. 03/15/2023 .PREV DISCUSSION... /ISSUED 1222 AM CDT Wed Mar 15 2023/ ...Synopsis... A shortwave trough will move into the western slopes of the Rockies today. Strong lee cyclogenesis is expected to occur in eastern Colorado this afternoon. Behind a dryline in the southern High Plains and a Pacific cold front in the Southwest, dry and windy conditions will be possible from the Trans-Pecos into eastern New Mexico, the combined Panhandles, southeast Colorado and southwest Kansas. RH of 20-25% is expected, particularly with northern extent. This is in part due to continued moisture influx in the southern Plains as well as mid/upper-level clouds across the region. There are areas that could see 15-20% RH at least for a short period. The most likely areas for this will be in parts of the Trans-Pecos into southeastern New Mexico where a greater downslope wind component will exist. Winds will tend to be stronger where RH may be higher, closer to the surface low. 20-30 mph winds in the vicinity of the Panhandles will weaken to 15-20 mph in the Trans-Pecos. Elevated fire weather is expected within the southern High Plains with some locally critical conditions possible where greater heating and mixing can occur. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

Bartlesville’s water supply continued to decline due to drought conditions in southeast Kansas. The city began a public awareness campaign in December to increase water conservation, but water use has stayed roughly normal for this time of year. The water supply level has fallen from 71% to 63.6%. The City Council might consider modifications to the Water Storage Ordinance and a resolution to enact emergency water rates during its upcoming April meeting. In addition, the new water slides in Sooner Park may not open this year if water levels continue to drop. Bartlesville Examiner-Enterprise (Okla.), March 15, 2023 Residents of Bartlesville were asked to conserve water because Hulah Lake was at 65% of capacity, although at this time of year, it’s usually at 90%. The city's water comes from an area of Kansas that is in extreme drought. Bartlesville fire and wastewater departments were also conserving water by not watering parks and closing car washes and wash facilities for city staff. Stricter water conservation measures may be needed if the lake’s water level continues to fall. KOTV-TV CBS 6 Tulsa (Okla.), Feb 24, 2023

No watches are valid as of Tue Mar 14 21:26:02 UTC 2023.

No Mesoscale Discussions are in effect as of Tue Mar 14 21:26:02 UTC 2023.

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Tue Mar 14 2023 Valid 151200Z - 161200Z No updates are required to the current Day 2 Fire Weather Outlook. See previous discussion below. ..Thornton.. 03/14/2023 .PREV DISCUSSION... /ISSUED 0138 AM CDT Tue Mar 14 2023/ ...Synopsis... A mid-level trough will traverse the InterMountain West on Tuesday night. As it emerges across the Rockies on Wednesday, lee cyclogenesis is anticipated with a surface low somewhere in eastern Colorado. Dry and breezy conditions are expected west of a dryline from Far West Texas to the OK/TX Panhandles and into southwest Kansas. Relative humidity will be in the teens across southeast New Mexico and Far West Texas where winds will increase to around 15 to 20 mph. Farther north, winds of 25-30 mph are expected across northeast New Mexico and the TX/OK Panhandles. Relative humidity is likely to remain at or above 20 percent in this region, in some part due to mid-upper level cloud cover which could limit heating. However, winds are strong enough to support an Elevated delineation, even with marginal relative humidity. In addition, if more significant cloud breaks can develop, deeper mixing is anticipated and Critical conditions would become more likely. ...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 0246 PM CDT Tue Mar 14 2023 Valid 151200Z - 161200Z No updates are required to the current Day 2 Fire Weather Outlook. See previous discussion below. ..Thornton.. 03/14/2023 .PREV DISCUSSION... /ISSUED 0138 AM CDT Tue Mar 14 2023/ ...Synopsis... A mid-level trough will traverse the InterMountain West on Tuesday night. As it emerges across the Rockies on Wednesday, lee cyclogenesis is anticipated with a surface low somewhere in eastern Colorado. Dry and breezy conditions are expected west of a dryline from Far West Texas to the OK/TX Panhandles and into southwest Kansas. Relative humidity will be in the teens across southeast New Mexico and Far West Texas where winds will increase to around 15 to 20 mph. Farther north, winds of 25-30 mph are expected across northeast New Mexico and the TX/OK Panhandles. Relative humidity is likely to remain at or above 20 percent in this region, in some part due to mid-upper level cloud cover which could limit heating. However, winds are strong enough to support an Elevated delineation, even with marginal relative humidity. In addition, if more significant cloud breaks can develop, deeper mixing is anticipated and Critical conditions would become more likely. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Tue Mar 14 2023 Valid 142000Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely over the conterminous U.S. through tonight. Little change was made to the previous outlook, with a minimal threat of thunderstorms across the CONUS. In the near term, showers from western North TX into southeastern TX may produce sporadic lightning flashes as a shortwave trough dives southeastward across the area, and utilizes moisture near 700 mb. Elsewhere, convergence over far southern FL and continued heating may lead to weak convection near Biscayne Bay, while upslope flow into the Sierra enhances lift with a chance of isolated thunderstorms later today. ..Jewell.. 03/14/2023 .PREV DISCUSSION... /ISSUED 1121 AM CDT Tue Mar 14 2023/ ...Synopsis/Discussion... In mid/upper levels, the pattern will remain characterized by a progressive, higher-amplitude northern stream pattern and conjoined, but lower-amplitude, southern stream of westerlies. A strong mid/upper-level low -- evident in moisture-channel imagery and morning RAOB data over PA -- will move roughly eastward today. By 00Z, over the Cape Cod vicinity, this feature will become vertically stacked with its occluded low-level counterpart now apparent over southern New England. The deep-layer cyclone then should move away from the northern Atlantic Coast, with any related thunder far out to sea. Convection-supporting lift accompanying the associated/trailing cold front across the Straits of FL to the western Gulf should continue to shift southward and/or gradually weaken through the period. As such, overland thunder potential now appears too minimal to keep in the outlook, except for isolated sea-breeze convective potential over a small part of southeastern FL. A low-amplitude, southern-stream shortwave trough -- initially over the eastern TX Panhandle, northwest TX and western OK -- will move southeastward across the Arklatex and lower Mississippi Delta region by the end of the period. In the associated large-scale lift/DCVA and warm-advection plumes, enough low/middle-level moisture exists to support weak elevated buoyancy and isolated thunder potential today, from the upper Red River area to parts of east TX. Farther west, a prominent, but not particularly intense mid/upper-level trough is apparent offshore from central/northern CA. This perturbation is preceded by an expansive precip shield over most of CA from the Sierra westward. Buoyancy is weak and generally confined below ideal icing levels for lightning. However, with large-scale lift/cooling lowering those levels through the day as the trough approaches (and similarly tonight, farther inland across the Great Basin), and at least marginal moisture available, a few episodic bursts or streaks of lightning may occur within outlooked broad areas of potential. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Tue Mar 14 2023 Valid 142000Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely over the conterminous U.S. through tonight. Little change was made to the previous outlook, with a minimal threat of thunderstorms across the CONUS. In the near term, showers from western North TX into southeastern TX may produce sporadic lightning flashes as a shortwave trough dives southeastward across the area, and utilizes moisture near 700 mb. Elsewhere, convergence over far southern FL and continued heating may lead to weak convection near Biscayne Bay, while upslope flow into the Sierra enhances lift with a chance of isolated thunderstorms later today. ..Jewell.. 03/14/2023 .PREV DISCUSSION... /ISSUED 1121 AM CDT Tue Mar 14 2023/ ...Synopsis/Discussion... In mid/upper levels, the pattern will remain characterized by a progressive, higher-amplitude northern stream pattern and conjoined, but lower-amplitude, southern stream of westerlies. A strong mid/upper-level low -- evident in moisture-channel imagery and morning RAOB data over PA -- will move roughly eastward today. By 00Z, over the Cape Cod vicinity, this feature will become vertically stacked with its occluded low-level counterpart now apparent over southern New England. The deep-layer cyclone then should move away from the northern Atlantic Coast, with any related thunder far out to sea. Convection-supporting lift accompanying the associated/trailing cold front across the Straits of FL to the western Gulf should continue to shift southward and/or gradually weaken through the period. As such, overland thunder potential now appears too minimal to keep in the outlook, except for isolated sea-breeze convective potential over a small part of southeastern FL. A low-amplitude, southern-stream shortwave trough -- initially over the eastern TX Panhandle, northwest TX and western OK -- will move southeastward across the Arklatex and lower Mississippi Delta region by the end of the period. In the associated large-scale lift/DCVA and warm-advection plumes, enough low/middle-level moisture exists to support weak elevated buoyancy and isolated thunder potential today, from the upper Red River area to parts of east TX. Farther west, a prominent, but not particularly intense mid/upper-level trough is apparent offshore from central/northern CA. This perturbation is preceded by an expansive precip shield over most of CA from the Sierra westward. Buoyancy is weak and generally confined below ideal icing levels for lightning. However, with large-scale lift/cooling lowering those levels through the day as the trough approaches (and similarly tonight, farther inland across the Great Basin), and at least marginal moisture available, a few episodic bursts or streaks of lightning may occur within outlooked broad areas of potential. Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1150 AM CDT Tue Mar 14 2023 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast on Wednesday. ...Synopsis and Discussion... On Wednesday, a deep upper low will exit the Northeast with an upper ridge progressing east across the MS Valley. Meanwhile, a lengthy positive-tilt upper trough will move across the Rockies, reaching the High Plains by 12Z Thursday. Behind the eastern trough, a surface high will provide cool and stable conditions to the eastern half of the CONUS. Low-level moisture will return into the southern Plains overnight, as low pressure develops over the central Plains in response to the western trough. Dewpoints above 60 F are expected as far north as central TX by 12Z Thursday, with 50s F dewpoints as far north as the surface low in southern KS ahead of a cold front. While the air mass over the Plains will remain capped for surface-based parcels, weak elevated instability may develop into early Thursday morning over OK, southern KS, AR, and northern TX. Any activity is expected to be isolated, as large-scale ascent only begins to increase late in the period, and capping even for elevated parcels remains a possibility. Weak instability overall will preclude severe probabilities. ..Jewell.. 03/14/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1150 AM CDT Tue Mar 14 2023 Valid 151200Z - 161200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast on Wednesday. ...Synopsis and Discussion... On Wednesday, a deep upper low will exit the Northeast with an upper ridge progressing east across the MS Valley. Meanwhile, a lengthy positive-tilt upper trough will move across the Rockies, reaching the High Plains by 12Z Thursday. Behind the eastern trough, a surface high will provide cool and stable conditions to the eastern half of the CONUS. Low-level moisture will return into the southern Plains overnight, as low pressure develops over the central Plains in response to the western trough. Dewpoints above 60 F are expected as far north as central TX by 12Z Thursday, with 50s F dewpoints as far north as the surface low in southern KS ahead of a cold front. While the air mass over the Plains will remain capped for surface-based parcels, weak elevated instability may develop into early Thursday morning over OK, southern KS, AR, and northern TX. Any activity is expected to be isolated, as large-scale ascent only begins to increase late in the period, and capping even for elevated parcels remains a possibility. Weak instability overall will preclude severe probabilities. ..Jewell.. 03/14/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1149 AM CDT Tue Mar 14 2023 Valid 141700Z - 151200Z ...NO CRITICAL AREAS... The current D1 Fire Weather Outlook is on track, with no changes anticipated. See previous discussion below. ..Thornton.. 03/14/2023 .PREV DISCUSSION... /ISSUED 0137 AM CDT Tue Mar 14 2023/ ...Synopsis... A very strong (sub 990mb) surface low will persist off/near the Northeast Coast for much of the day Tuesday. This will result in moderate offshore flow across the entire East Coast. Some dry and breezy conditions are possible in southern Virginia and much of North Carolina. However, recent rainfall has tampered fuel dryness and therefore elevated fire weather concerns are not anticipated. Farther south, northwesterly, down-peninsula flow will lead to dry conditions across Florida with winds around 10 to 13 mph. Most of the Peninsula is in a Moderate drought, and fuels are dry, particularly in the southern half of the Peninsula. Some thunderstorms did move across the state on Monday, but precipitation coverage was relatively scattered and therefore, fuels remain dry in most of the region. ...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 1149 AM CDT Tue Mar 14 2023 Valid 141700Z - 151200Z ...NO CRITICAL AREAS... The current D1 Fire Weather Outlook is on track, with no changes anticipated. See previous discussion below. ..Thornton.. 03/14/2023 .PREV DISCUSSION... /ISSUED 0137 AM CDT Tue Mar 14 2023/ ...Synopsis... A very strong (sub 990mb) surface low will persist off/near the Northeast Coast for much of the day Tuesday. This will result in moderate offshore flow across the entire East Coast. Some dry and breezy conditions are possible in southern Virginia and much of North Carolina. However, recent rainfall has tampered fuel dryness and therefore elevated fire weather concerns are not anticipated. Farther south, northwesterly, down-peninsula flow will lead to dry conditions across Florida with winds around 10 to 13 mph. Most of the Peninsula is in a Moderate drought, and fuels are dry, particularly in the southern half of the Peninsula. Some thunderstorms did move across the state on Monday, but precipitation coverage was relatively scattered and therefore, fuels remain dry in most of the region. ...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 1121 AM CDT Tue Mar 14 2023 Valid 141630Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely over the conterminous U.S. through tonight. ...Synopsis/Discussion... In mid/upper levels, the pattern will remain characterized by a progressive, higher-amplitude northern stream pattern and conjoined, but lower-amplitude, southern stream of westerlies. A strong mid/upper-level low -- evident in moisture-channel imagery and morning RAOB data over PA -- will move roughly eastward today. By 00Z, over the Cape Cod vicinity, this feature will become vertically stacked with its occluded low-level counterpart now apparent over southern New England. The deep-layer cyclone then should move away from the northern Atlantic Coast, with any related thunder far out to sea. Convection-supporting lift accompanying the associated/trailing cold front across the Straits of FL to the western Gulf should continue to shift southward and/or gradually weaken through the period. As such, overland thunder potential now appears too minimal to keep in the outlook, except for isolated sea-breeze convective potential over a small part of southeastern FL. A low-amplitude, southern-stream shortwave trough -- initially over the eastern TX Panhandle, northwest TX and western OK -- will move southeastward across the Arklatex and lower Mississippi Delta region by the end of the period. In the associated large-scale lift/DCVA and warm-advection plumes, enough low/middle-level moisture exists to support weak elevated buoyancy and isolated thunder potential today, from the upper Red River area to parts of east TX. Farther west, a prominent, but not particularly intense mid/upper-level trough is apparent offshore from central/northern CA. This perturbation is preceded by an expansive precip shield over most of CA from the Sierra westward. Buoyancy is weak and generally confined below ideal icing levels for lightning. However, with large-scale lift/cooling lowering those levels through the day as the trough approaches (and similarly tonight, farther inland across the Great Basin), and at least marginal moisture available, a few episodic bursts or streaks of lightning may occur within outlooked broad areas of potential. ..Edwards/Supinie.. 03/14/2023 Read more