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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1216 PM CDT Wed Apr 12 2023 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN HIGH PLAINS AND INTO PORTIONS OF THE SOUTHEAST.... ...SUMMARY... Isolated severe thunderstorms are possible across portions of the southern and central High Plains and portions of the Southeast States/Florida on Thursday. ...Synopsis... A mid-level closed low over the Gulf of Mexico is forecast to continue to slowly meander eastward while the associated surface circulation moves onshore early Thursday. Scattered strong thunderstorms should move inland early, and persist through much of the day. To the west, a mid-level trough digging over the central Rockies and northern Great Basin will shift eastward overspreading the central High Plains. A strong lee low is forecast to evolve aiding in the development of a dryline and weak moisture return over the western High Plains. Isolated severe thunderstorms are possible in the afternoon and evening ahead of the sharpening dryline. ...Southeastern States... As the closed low shifts northeastward across the central Gulf Coast, rapid low-level moistening is expected in its eastern quadrant early in the forecast period. Mid, to eventually upper, 60s F surface dewpoints will surge inland over portions of eastern MS/AL, into southern GA and much of FL by midday. Weak mid-level warm advection and a mostly uncapped surface warm sector should allow for loosely organized bands of scattered thunderstorms to move onshore and develop through much of the day. Limited by mostly cloudy skies, afternoon destabilization is not expected to be overly strong, but diffuse heating and returning surface moisture should be sufficient to support scattered thunderstorms and occasional stronger updrafts. Mid-level shear is also not particularly strong owing the weaker flow aloft on the eastern periphery of the upper-level circulation. However, enhanced easterly flow in the low to mid-levels supports some hodograph curvature/expansion in the lowest few kilometers. Given the favorable storm relative flow and larger SRH (200 m2/s2), transient supercell structures may evolve with the more persistent updrafts. The strongest storms may pose a risk for damaging wind gusts and a tornado or two into the early evening. A few storms may also be capable of marginally severe hail given cooler temperatures aloft. ...Central and southern High Plains... As the western US trough continues to deepen and shift eastward through the day, broad-scale ascent and an embedded shortwave trough will overspread a sharpening dryline/lee trough extending south from a lee low over western NE. Strong diurnal heating and mixing along the dryline will remove limited inhibition concurrent with northward returning surface moisture. While not excessively moist, surface dewpoints reaching the upper 30s to mid 40s F should be adequate for weak afternoon destabilization given the very warm temperatures and steep lapse rates. The warm temperatures and marginal moisture should support around 500 J/kg of MLCAPE allowing the development of isolated high-based storms late in the afternoon. Steepening low-level lapse rates will favor strong downdrafts and severe wind gust potential with any convection able to develop. The greatest converge of storms is currently expected over portions of the TX Panhandle into southwestern KS where deeper surface moisture and locally stronger surface convergence are expected along the dryline. Given the limited surface moisture, storms should diminish quickly after sunset with the loss of diurnal heating. A Marginal Risk area has been added from central NE to the southern TX Panhandle mainly for isolated damaging wind gusts. ..Lyons/Dean.. 04/12/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Wed Apr 12 2023 Valid 121630Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE GULF COAST... ...SUMMARY... Isolated damaging wind gusts and/or a tornado are possible along parts of the Gulf Coast late tonight into Thursday morning. ...Gulf Coast including southern portions MS/AL and FL Panhandle... With the mid-level portion of the cyclone centered along the southwest Louisiana coast this morning, the low-level circulation is expected to intensify and shift northward and reach coastal southeast Mississippi/far southwest Alabama vicinity by Thursday morning. However, it is noted that there are several-MB differences, even in the short term, with the progged deepening of the surface low and its northeast-peripheral strengthening wind field among model guidance (e.g. 12z NAM one of the more aggressive solutions). Even more modest-strength/slower solutions suggest that the near-coastal environment could become conducive to some severe-weather potential late tonight into Thursday, including locally damaging winds and a tornado risk. This will be as an increasingly moist air mass via a northward-shifting warm front approaches and moves inland. Mid-level winds will remain modest-strength, but strengthening low-level shear/SRH should be adequate for at least some near-coastal transient supercells, with the potential persisting into Thursday (see Day 2). ..Guyer/Weinman.. 04/12/2023 Read more

No watches are valid as of Tue Apr 11 21:23:02 UTC 2023.

No Mesoscale Discussions are in effect as of Tue Apr 11 21:23:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Tue Apr 11 2023 Valid 112000Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected over the U.S. today and tonight. ...20z Update... No major changes have been made to the outlook. A few areas of general thunderstorms remain possible over the Lower 48 through this evening, but severe weather is not expected. Please see the previous discussion for more information. ..Lyons/Dean.. 04/11/2023 .PREV DISCUSSION... /ISSUED 1118 AM CDT Tue Apr 11 2023/ ...Synopsis/Discussion... A midlevel trough will continue slowly eastward over the Northwest today/tonight, providing enough lift (aided by orographic effects) to support isolated lightning flashes across the Pacific Northwest this afternoon/evening given steepening lapse rates and adequate buoyancy. Farther east, a positively tilted mid/upper-level trough will drift south/southeastward over the lower MS Valley vicinity into the northwestern Gulf of Mexico, becoming a closed upper low late in the period. Several embedded lobes of ascent (evident in water-vapor imagery) rotating around this feature, combined with filtered diurnal heating of a partially modified gulf air mass, will favor isolated to widely scattered thunderstorms over southern LA and parts of south TX. Over southern FL and the Keys, enhanced low-level easterlies and deep boundary-layer moisture along/north of a remnant frontal boundary will support periodic bands of convection, with the greater lightning potential expected over the FL Straits and spreading northward late in the period. Marginal buoyancy and weak deep-layer shear should generally limit convective intensity/organization across the CONUS, though a loosely organized storm or two cannot be entirely ruled out near the FL Keys. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Tue Apr 11 2023 Valid 121200Z - 131200Z ...High Plains to central Plains... Latest guidance continues to show reasonably high confidence in widespread elevated conditions from the greater Panhandles region into the central Plains as gradient winds increase by mid-day. Localized critical conditions appear possible across parts of western KS into southwest NE, but confidence in the overlap of the strongest winds (over central KS/NE) with the drier air mass (over eastern CO/western NE) remains limited per latest ensemble guidance and deterministic RAP runs. The coverage of elevated conditions is likely under-done in most model solutions given the recent cool/moist bias over the past several days. Consequently, the risk area has been expanded based on recent RAP solutions (which have been handling boundary-layer mixing the best out of any guidance). ...Midwest... The Elevated risk area has been expanded eastward into portions of southern WI/northern IL. Recent RAP forecasts suggests afternoon RH values in the mid to upper 20s are probable across eastern IA into southern WI/northern IL. Gradient winds near 20 mph appear likely, and should support elevated fire weather conditions where RH criteria are met. 10+ hour fuels across this region appear to be unreceptive based on recent fuel moisture analyses and drought indices, but fuel reports from local offices/fire agencies indicate that fine (1-hour) fuels are sufficiently dry to support a fire weather concern. ...Northeast... Gradient winds on the northeast periphery of the southern surface high are expected to strengthen to near 15 mph with gusts approaching 20 mph. While winds may be stronger/more widespread on Wednesday as compared to today/Tuesday, RH is forecast to be slightly higher with minimums near 25-35% based on latest RAP forecasts. Confidence in the spatial extent and coverage of the fire weather threat is uncertain, but localized elevated conditions appear probable across parts of the Mid-Atlantic to New England region. ..Moore.. 04/11/2023 .PREV DISCUSSION... /ISSUED 0225 AM CDT Tue Apr 11 2023/ ...Synopsis... A Rex block will setup across the Mississippi Valley region on Wednesday. The strong trough in the Northwest will continue to slowly move eastward. A similar surface pattern to Tuesday is expected with a slightly deeper lee trough in the High Plains along with a weakened, but still stout, Southeast surface high. ...Parts of southern High Plains and central Plains... With a stronger lee trough, similarly dry and windy conditions are possible again across much of the same areas as Tuesday. Winds in parts of Kansas into Nebraska may be stronger, but some additional moisture return may slightly increase RH values during the afternoon. Winds of 15-20 mph are more likely near the southern High Plains, increasing to perhaps 20+ mph into eastern Nebraska/western Iowa. RH 10-20% will exist in the High Plains with values closer to 20-25% farther north and east. Given the dry fuels in the region and similar conditions to Tuesday, elevated fire weather is again expected. ...Parts of Upper Midwest... Locally dry and windy conditions are possible as the pressure gradient strengthens across the region. Dry southwesterly winds may lead to RH around 20-25% as temperatures warm into the afternoon. Winds are expected to be strongest in the morning appear to be mostly out of phase with the lowest RH. Fire weather conditions will be elevated on a local basis, where fuels are dry, however. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Tue Apr 11 2023 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG THE CENTRAL GULF COAST AND THE WESTERN FLORIDA PANHANDLE.... ...SUMMARY... Isolated thunderstorms are possible over portions of the central High Plains, the southern and central Rockies, and the central Gulf Coast/Florida Wednesday into the overnight hours. A few storms along the Gulf Coast may produce isolated damaging winds and a tornado or two. ...Synopsis... Across the CONUS, split mid-level flow will persist through much of the forecast period as a stubborn cut off low lingers along the central Gulf Coast. To the west, a Pacific trough will dig south toward the Great Basin as a speed max moves onshore. With the cut off low remaining in place, much of the stronger polar jet will remain displaced to the north across the international border. At the surface, high pressure will remain dominant in the eastern CONUS while several surface lows consolidate over the Intermountain West. Isolated thunderstorms are possible across portions of the Rockies into the central/northern Plains. A few severe storms are also possible along the Gulf Coast. ...Central Gulf Coast to the western Florida Panhandle... To the east of the cut off upper low, a weak area of surface low pressure is expected to develop over the Gulf of Mexico late D2/Wed into early D3/Thur. Some models indicate the potential for some intensification of the surface system as it approaches the coast. Inland moisture advection, and modest pressure falls near the surface low may support enough buoyancy and shear for a few organized, and possibly rotating storms. Model guidance varies considerably on the timing and positioning of the upper and surface lows near the Gulf Coast. If the low is able to move near/onshore and displace a wedge of cooler continental air overnight, a few rotating storms may move inland prior to 12z D3/Thur. With RAP soundings showing strongly backed surface winds and 0-1km SRH of 200-250 m2/s2, a risk for damaging wind gusts and a tornado or two may evolve with the stronger storms. Portions of far southern LA, as well as coastal MS/AL, and the western FL Panhandle appear to be the most likely corridor for any severe potential late in the forecast period. A small Marginal Risk area has been added along the immediate coast to cover this threat. ...Rockies on to the Central/Northern Plains... Isolated thunderstorms are possible ahead of the deepening mid-level trough over the Great Basin/Intermountain West and onto the High Plains. While flow aloft is forecast to increase supporting moderate vertical shear, limited surface moisture should keep buoyancy relatively low. A few elevated storms are also possible over the Plains during the evening and overnight, amid strong warm-air advection from a robust low-level jet. In each case, limited buoyancy should mitigate the overall severe potential. ..Lyons/Dean.. 04/11/2023 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0245 PM CDT Mon Apr 10 2023 Valid 111200Z - 121200Z ...Central Plains... Dry and breezy conditions will remain possible D2/Tuesday in the vicinity of a surface trough/cold front. While not overly strong, wind gusts of 15-20 mph atop dry fuels with low RH will likely promote elevated fire-weather conditions. The Elevated area was expanded slightly on the north end to better cover the overlap of dry and windy conditions. ...Northeast... At the base of an approaching upper trough, strong flow aloft may support a low-end fire-weather risk across portions of Upstate NY into VE/NH. A cold front/surface trough will sweep eastward, supporting strong wind gusts along and behind it. However, the best diurnal mixing is expected ahead of the front farther east with afternoon RH values near 25-30%. The poor overlap of strong winds behind the front and low RH ahead of it suggests low confidence in sustained fire-weather conditions. See the previous discussion for additional information. ..Lyons.. 04/10/2023 .PREV DISCUSSION... /ISSUED 0111 AM CDT Mon Apr 10 2023/ ...Synopsis... The strong trough across the Northwest will nudge into the northern Rockies on Tuesday. A lee trough will deepen in the central/northern High Plains in response. Trajectories across much of the Plains will continue to remain continental in origin out of the surface high in the Southeast. As such, relatively dry southerly return flow will allow RH to fall to 20-25% in parts of the central Plains. Perhaps locally lower values will be possible within the central High Plains. The increase in the low-level pressure gradient during the afternoon will promote 15-20 mph winds. Given the state of fuels, elevated to near critical conditions appear possible. In the Northeast, a strong upper-level trough will dig into the region during the afternoon/evening. Dry, westerly winds appear possible. Mid/upper-level clouds will be plentiful. Some areas near the coast may be able to warm enough to support RH of 25-35%. Some guidance even suggests RH near 20% could occur. Sustained winds, however, are not expected to be overly strong (10-15 mph). Stronger flow just off the surface will be able to mix down in some areas and produce gusts up to 20 mph. Given the expected light winds and the potential cloud cover, only locally elevated conditions are expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Mon Apr 10 19:47:01 UTC 2023.

MD 0501 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF WESTERN INTO NORTH CENTRAL OKLAHOMA AND ADJACENT PORTIONS OF SOUTHERN KANSAS
Mesoscale Discussion 0501 NWS Storm Prediction Center Norman OK 0240 PM CDT Mon Apr 10 2023 Areas affected...Parts of western into north central Oklahoma and adjacent portions of southern Kansas Concerning...Severe potential...Watch unlikely Valid 101940Z - 102215Z Probability of Watch Issuance...20 percent SUMMARY...A few strong storms posing at least some risk for severe weather appear possible by 5-7 PM CDT. It is not clear that a severe weather watch is needed, but trends will continue to be monitored for this possibility. DISCUSSION...Low-level forcing for ascent is rather weak, but a lingering confluence zone near the interface of a corridor of stronger surface heating and modest boundary-layer moisture is becoming the focus for destabilization across parts of northwestern Oklahoma through eastern Kansas. While this is likely to remain characterized by mixed-layer CAPE less than 1000 J/kg, low-level lapse rates are becoming steep beneath seasonably cool mid-level air around -18C. Scattered convection is beginning to from and deepen in response to the continuing surface heating, and model output generally indicates that this will lead to the development of a few thunderstorms by 23-00Z. It appears that stronger storms may gradually focus where deep-layer shear and mid-level forcing for ascent become maximized, near the left exit region of a digging northerly mid-level jet streak (around 40 kt at 500 mb), roughly near and south-southwest of the Enid vicinity. Given the environment, some of these storms may pose a risk for (mostly) sub-severe to marginally severe hail and wind gusts. ..Kerr/Guyer.. 04/10/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TSA...ICT...OUN... LAT...LON 37239727 36819682 35729780 35319861 35909888 37239727 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0235 PM CDT Mon Apr 10 2023 Valid 102000Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST KANSAS THROUGH WEST-CENTRAL OKLAHOMA... ...SUMMARY... Scattered severe hail and isolated thunderstorm gusts are expected through this evening from northwest Texas across central Oklahoma to southeastern Kansas. ...20z Update -- Southern Plains... Aside from modifications to the 10 percent general thunderstorm line based on current obs and model trends, no changes have been made to the outlook with the 20z update. Isolated to widely scattered thunderstorms are expected to develop southward near the surface trough from eastern KS into OK and northwest TX through this evening. Isolated large hail and strong gusts will be possible with these storms given sufficient vertical shear in a modestly unstable environment. Severe potential is expected to diminish after 04z this evening. For more details on short term severe potential, reference MCD 501. ..Leitman.. 04/10/2023 .PREV DISCUSSION... /ISSUED 1132 AM CDT Mon Apr 10 2023/ ...Northwest TX to southeast KS... Along the eastern periphery of an amplified large-scale ridge encompassing the western CONUS, a midlevel speed maximum -- embedded in northerly flow aloft -- will dive southward and gradually strengthen across the central and southern Plains into this evening. While the low-level mass response accompanying this feature will be minimal, a northeast-southwest-oriented surface trough (and accompanying wind shift) is already in place from east-central KS southwestward through west-central OK into northwest TX this morning. In response to the strengthening northerlies aloft, this feature will move slightly south-southeastward today, remaining over the central/southern Plains during the afternoon/evening hours. Along/south of the surface trough, lower/middle 50s surface dewpoints and efficient boundary-layer heating/mixing should support widely scattered to scattered thunderstorm development along the surface trough/wind shift in the 19-22Z time frame -- aided by subtle ascent accompanying the approaching speed maximum. Weak south-southeasterly low-level flow veering to deep/stronger northerly flow aloft will yield long/mostly straight north-south oriented hodographs supportive of splitting supercell structures. Given a steep low/mid-level lapse rate environment and the potential for maintained semi-discrete cells/clusters, scattered large hail and severe gusts are possible with the longer-lived storms into the evening hours. Confidence in a higher concentration of severe hail (some approaching 2 inch) is highest across portions of northern and western OK and southeast KS, and a Slight Risk has been added to account for this. In addition, given enhanced surface vorticity along the wind shift, slow-moving storms developing atop the boundary from southeast/south-central KS to north-central OK could produce a landspout or two (aided by favorable 0-3 km CAPE). ...Southern FL... As the left-exit region of an upper-level jet streak overspreads deep tropospheric moisture and modest deep-layer lapse rates this afternoon, long/straight hodographs could favor a couple loosely organized storms capable of strong winds this afternoon. However, the potential for organized/long-lived storms appears too low for severe probabilities at this time. Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1209 PM CDT Mon Apr 10 2023 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible over the Florida Peninsula and Pacific Northwest as well as from the Texas Hill Country to the western Gulf Coast on Tuesday. Severe thunderstorms are not expected. ...Synopsis... A closed upper low will persist near the northwest Gulf coast vicinity on Tuesday. Surface high pressure centered over the TN Valley will generally keep deeper Gulf moisture offshore, except across the TX Coast into far southern LA where dewpoints in the 50s to near 60 F will be in place. Weak buoyancy in the presence of this modest boundary-layer moisture will support isolated thunderstorms near the northwest Gulf coast vicinity westward to the Edwards Plateau/TX Hill Country vicinity. Limited instability and weak vertical shear will preclude severe potential. Additional isolated lightning flashes are possible across south FL where 60s F dewpoints will remain in place. Modest diurnal destabilization will support isolated thunderstorms during the afternoon. Across the Pacific Northwest, a strong upper shortwave trough will move onshore and shift eastward to the northern Rockies. Cooling aloft and steep midlevel lapse rates will support isolated thunderstorms across parts of northwest OR, much of WA and into northern ID/far northwest MT. ..Leitman.. 04/10/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Mon Apr 10 2023 Valid 101700Z - 111200Z ...NO CRITICAL AREAS... The previous forecast remains valid with no changes. Fire-weather concerns are low. ..Lyons.. 04/10/2023 .PREV DISCUSSION... /ISSUED 0109 AM CDT Mon Apr 10 2023/ ...Synopsis... Surface high pressure will be the dominant feature across much of the lower 48 today as an upper-level ridge continues to shift east. A strong upper-level trough will impact the Northwest late in the period. Winds in some parts of the Plains will increase during the evening/overnight, as surface low pressure develops in the northern High Plains in response to the trough. However, only light winds are expected over areas of dry fuels, and fire weather concerns will remain minimal. ...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 1132 AM CDT Mon Apr 10 2023 Valid 101630Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST KS THROUGH WEST-CENTRAL OK... ...SUMMARY... Scattered severe hail and isolated thunderstorm gusts are expected this afternoon from northwest Texas across central Oklahoma to southeastern Kansas. ...Northwest TX to southeast KS... Along the eastern periphery of an amplified large-scale ridge encompassing the western CONUS, a midlevel speed maximum -- embedded in northerly flow aloft -- will dive southward and gradually strengthen across the central and southern Plains into this evening. While the low-level mass response accompanying this feature will be minimal, a northeast-southwest-oriented surface trough (and accompanying wind shift) is already in place from east-central KS southwestward through west-central OK into northwest TX this morning. In response to the strengthening northerlies aloft, this feature will move slightly south-southeastward today, remaining over the central/southern Plains during the afternoon/evening hours. Along/south of the surface trough, lower/middle 50s surface dewpoints and efficient boundary-layer heating/mixing should support widely scattered to scattered thunderstorm development along the surface trough/wind shift in the 19-22Z time frame -- aided by subtle ascent accompanying the approaching speed maximum. Weak south-southeasterly low-level flow veering to deep/stronger northerly flow aloft will yield long/mostly straight north-south oriented hodographs supportive of splitting supercell structures. Given a steep low/mid-level lapse rate environment and the potential for maintained semi-discrete cells/clusters, scattered large hail and severe gusts are possible with the longer-lived storms into the evening hours. Confidence in a higher concentration of severe hail (some approaching 2 inch) is highest across portions of northern and western OK and southeast KS, and a Slight Risk has been added to account for this. In addition, given enhanced surface vorticity along the wind shift, slow-moving storms developing atop the boundary from southeast/south-central KS to north-central OK could produce a landspout or two (aided by favorable 0-3 km CAPE). ...Southern FL... As the left-exit region of an upper-level jet streak overspreads deep tropospheric moisture and modest deep-layer lapse rates this afternoon, long/straight hodographs could favor a couple loosely organized storms capable of strong winds this afternoon. However, the potential for organized/long-lived storms appears too low for severe probabilities at this time. ..Weinman/Guyer.. 04/10/2023 Read more

No watches are valid as of Sun Apr 9 20:19:01 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sun Apr 09 2023 Valid 092000Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorm gusts and large hail are possible across portions of the southern High Plains this afternoon and evening. ...20z Update - Southern Plains... The previous forecast remains on track and no changes have been made with the 20z update. Isolated thunderstorms have developed this afternoon within the Marginal risk area, with one severe-warned storm currently across southwest OK. These storms may briefly become severe, producing strong gusts and near-one inch hail. Severe potential is expected to remain sporadic/marginal. ..Leitman.. 04/09/2023 .PREV DISCUSSION... /ISSUED 1128 AM CDT Sun Apr 09 2023/ ...Southern High Plains... A low-amplitude, southern-stream shortwave trough will continue advancing slowly eastward over the central/southern High Plains today, before gradually weakening and becoming absorbed into a more-pronounced northern-stream midlevel trough this evening/overnight. As this feature continues eastward, modestly enhanced midlevel westerly flow will gradually veer to northwesterly by this evening, while a related surface lee trough remains nearly stationary over the High Plains. East of the lee trough, two weak mesoscale lows have developed in response to early-morning/ongoing convection -- one over the TX Panhandle and the other near the TX South Plains. Along the southern/eastern peripheries of the northern mesoscale low/outflow boundary, lower 50s surface dewpoints are spreading northward in conjunction with filtered diurnal heating. As MLCINH erodes, additional surface-based convection should focus along this boundary over the southern TX Panhandle into far southwest OK this afternoon. Steep midlevel lapse rates and elongated mid/upper-level hodographs should favor a couple loosely organized, splitting supercell structures capable of large hail and locally severe gusts. Similarly, diurnal destabilization/steepening low-level lapse rates along/ahead of the southern mesoscale low/outflow boundary should favor additional convective development this afternoon. Given the steep deep-layer lapse rate environment and long/generally straight hodographs (30-40 kt of effective shear), isolated large hail is expected -- especially with the early/cellular development. From the afternoon into the evening/overnight hours, convection will generally spread/expand southeastward as midlevel flow veers on the backside of the weakening shortwave trough. Continued outflow generation amid slightly stronger deep-layer shear could support localized upscale growth/convective clustering and an increasing potential for severe gusts. Eventually, convection will impinge on increasing nocturnal boundary-layer stability and a residual midlevel capping inversion with southward extent, with a corresponding decrease in severe potential during the overnight hours. Read more

MD 0499 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF THE TEXAS PANHANDLE INTO SOUTHWEST OKLAHOMA AND NORTHWEST TEXAS
Mesoscale Discussion 0499 NWS Storm Prediction Center Norman OK 0120 PM CDT Sun Apr 09 2023 Areas affected...parts of the Texas Panhandle into southwest Oklahoma and northwest Texas Concerning...Severe potential...Watch unlikely Valid 091820Z - 092145Z Probability of Watch Issuance...20 percent SUMMARY...Scattered storms are likely to form after 20Z, and a few storms may produce hail over 1.00" diameter and locally strong wind gusts. DISCUSSION...Visible imagery shows strong heating over the panhandles and into much of the South Plains and northwest TX, the exception being the eastern TX Panhandle into western OK in association with a batch of showers and cirrus. CU is beginning to form within the surface trough from eastern NM into the TX Panhandle, with weak wind convergence. GPS PW sensors show a plume of 0.80-0.90" PWAT from northwest TX into the eastern TX Panhandle and South Plains, where dewpoints remain in the 50s F. The cold midlevel trough is currently over the area, which when combined with heating, continues to steepen lapse rates. Scattered storms are expected to form both along the weak convergence zone and farther east into the moist plume, where differential heating near the outflow/clouds exists. The steep lapse rates and sufficient deep-layer shear will favor a few storms producing hail around 1.00-1.50" diameter, especially later in the day. Mixed storm modes are expected, with locally strong wind gusts with the outflows as well. ..Jewell/Guyer.. 04/09/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN...LUB...AMA... LAT...LON 35249935 34619936 33989952 33639978 33450029 33460097 33930147 34600195 35420199 35850150 36300095 36460039 36149982 35899954 35249935 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0114 PM CDT Sun Apr 09 2023 Valid 101200Z - 111200Z ...NO CRITICAL AREAS... The previous forecast remains on track. Recent guidance continues to show low probability for elevated or critical fire weather conditions over areas with receptive fuels. See the previous discussion for additional details. ..Moore.. 04/09/2023 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sun Apr 09 2023/ ...Synopsis... Upper-level ridging will continue to shift eastward on Monday. A stronger mid-level trough will impact the Pacific Northwest. At the surface, a high-pressure center in the Southeast will remain in place. In the northern Plains, a low will develop in response the approaching trough. Surface winds in the Plains will generally be light for much of day, with an increase during the evening/overnight when RH will have increased. Fire weather concerns will be minimal. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1214 PM CDT Sun Apr 09 2023 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated to scattered thunderstorms are possible across portions of the southern Plains as well as the Florida Peninsula. Severe thunderstorms are not currently anticipated. ...Synopsis... A weak shortwave trough will migrate east across the central/southern Plains and Mid to Lower-MS Valley on Monday. Boundary-layer moisture will remain modest as surface high pressure over the eastern U.S. and over the Rockies suppresses stronger Gulf return flow. Nevertheless, mainly 50s F (to low 60s over central/south TX) dewpoints beneath modest midlevel lapse rates and some diurnal heating will support thunderstorm development from southeast KS/southwest MO into OK/TX through the period. Deep-layer flow will remain light, but directional shear will support effective shear magnitudes around 25-35 kt. A couple of strong storms may produce small hail or gusty winds across parts of central OK into central TX. Weak large-scale ascent coupled with modest instability and modest shear will likely limit longevity of any better organized cells, and severe potential appears too low to include probabilities at this time. Moderate northeasterly low/midlevel flow is forecast across the FL Peninsula on Monday. Early day thunderstorms along the east coast will shift/develop west/southwest through the afternoon. MLCAPE to around 1500 J/kg and modest effective shear may support some stronger cells/clusters capable of gusty winds and small hail across southern and central portions of the Peninsula. Warming around 700 mb and poor lapse rates noted in forecast soundings may inhibit a low-end severe threat, precluding probabilities at this time. ..Leitman.. 04/09/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Apr 09 2023 Valid 091630Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorm gusts and large hail are possible across portions of the southern High Plains this afternoon and evening. ...Southern High Plains... A low-amplitude, southern-stream shortwave trough will continue advancing slowly eastward over the central/southern High Plains today, before gradually weakening and becoming absorbed into a more-pronounced northern-stream midlevel trough this evening/overnight. As this feature continues eastward, modestly enhanced midlevel westerly flow will gradually veer to northwesterly by this evening, while a related surface lee trough remains nearly stationary over the High Plains. East of the lee trough, two weak mesoscale lows have developed in response to early-morning/ongoing convection -- one over the TX Panhandle and the other near the TX South Plains. Along the southern/eastern peripheries of the northern mesoscale low/outflow boundary, lower 50s surface dewpoints are spreading northward in conjunction with filtered diurnal heating. As MLCINH erodes, additional surface-based convection should focus along this boundary over the southern TX Panhandle into far southwest OK this afternoon. Steep midlevel lapse rates and elongated mid/upper-level hodographs should favor a couple loosely organized, splitting supercell structures capable of large hail and locally severe gusts. Similarly, diurnal destabilization/steepening low-level lapse rates along/ahead of the southern mesoscale low/outflow boundary should favor additional convective development this afternoon. Given the steep deep-layer lapse rate environment and long/generally straight hodographs (30-40 kt of effective shear), isolated large hail is expected -- especially with the early/cellular development. From the afternoon into the evening/overnight hours, convection will generally spread/expand southeastward as midlevel flow veers on the backside of the weakening shortwave trough. Continued outflow generation amid slightly stronger deep-layer shear could support localized upscale growth/convective clustering and an increasing potential for severe gusts. Eventually, convection will impinge on increasing nocturnal boundary-layer stability and a residual midlevel capping inversion with southward extent, with a corresponding decrease in severe potential during the overnight hours. ..Weinman/Guyer.. 04/09/2023 Read more