Severe Storms

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0232 PM CDT Tue Jun 06 2023 Valid 062000Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE NORTHEAST...NORTHERN CALIFORNIA TO NORTHERN UTAH/SOUTHERN IDAHO...NEW MEXICO/TEXAS TRANS-PECOS...SOUTH FLORIDA...AND THE SOUTH CAROLINA VICINITY... ...SUMMARY... Isolated severe thunderstorms with threats of damaging winds and large hail will be possible through this evening across several portions of the country: the South Carolina vicinity, the Northeast, northern California to northern Utah/southern Idaho, New Mexico/Texas Trans-Pecos, and south Florida. ...20Z Update... Overall forecast outlined in the previous outlook remains valid. Thunderstorms remain possible across a large portion of the CONUS, with stronger storms anticipated in a few areas, including portions of the Northeast, northern CA into the Great Basin, and southern High Plains. Each of these areas are addressed in the previous discussion. Additional details for the Northeast can be found in recently issued MCD #941, and for portions of northern California, north and central Nevada, and western Utah in MCD #942. In all, generally modest buoyancy and the lack of stronger flow aloft is expected to preclude a more widespread severe-thunderstorm threat. ..Mosier.. 06/06/2023 .PREV DISCUSSION... /ISSUED 1123 AM CDT Tue Jun 06 2023/ ...SC Vicinity... A plume of moderate buoyancy with MLCAPE of 1000-2000 J/kg centered on north GA will shift east into SC later this afternoon. Isolated to scattered thunderstorms will develop along and just ahead of a weak surface trough shifting slowly south across NC to upstate SC. The region will lie within the gradient of weak to moderate mid-level northwesterlies, well to the southwest of a deep upper low over the Canadian Maritimes. While low-level flow will remain weak and veered to the west-southwest, 15-25 kt effective bulk shear should support some multicell clustering and a threat for isolated damaging winds and severe hail. ...Northeast... A secondary mid-level impulse embedded within the larger-scale trough on the backside of the deep upper low over the Canadian Maritimes should aid in isolated to scattered higher-based convection. MLCAPE will remain weak owing to surface dew points only in the mid 40s to around 50 F. But moderate speed shear through the cloud-bearing layer should foster small to marginally severe hail growth in the deeper cores. This combined with an inverted-v thermodynamic profile will support a threat for locally damaging winds. Refer to the SPC Fire Weather Outlook for additional information. ...Northern CA to northern UT/southern ID... An upper low will wobble over the San Joaquin Valley through tonight. A belt of modest buoyancy with MLCAPE of 600-1200 J/kg should develop at peak heating within a largely west/east-oriented arc across northern CA to northern UT/southern ID. Scattered thunderstorms are expected within this buoyancy plume by late afternoon. While moderate mid-level flow will generally be displaced to the south, 20-30 kt southeasterlies around 500 mb will support some multicell clustering and a primary threat of isolated severe wind gusts. Small to marginally severe hail will also be possible in deeper updrafts. ...NM and the TX Trans-Pecos... Downstream of the CA upper low, scattered thunderstorms will develop within a modest buoyancy plume characterized by MLCAPE of 700-1400 J/kg. The bulk of stronger mid-level flow should remain displaced west of the buoyancy/higher PW plume in AZ, as a low-amplitude mid-level ridge tries to hold over central NM. As such, convection will likely struggle to initially organize with sporadic severe gusts and small hail being the main threats. Somewhat greater effective shear should occur from the TX Trans-Pecos to the Raton Mesa during the early evening, where isolated marginally severe storms may occur. ...South FL... Morning convection along the southeast FL coast has yielded outflow that has pushed inland over the Everglades. Later afternoon convection will probably be focused along this boundary into southwest FL. While a 50-kt speed max at 500 mb was sampled in the 12Z Miami sounding, guidance is consistent with weakening mid-level winds through the afternoon. It still should remain sufficient for a transient cell or two with mid-level rotation, and supportive of a brief threat for severe wind/hail. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 PM CDT Tue Jun 06 2023 Valid 071200Z - 081200Z The previous forecast remains valid with only minor adjustments for the latest forecast guidance. The Elevated area was expanded westward across lower MI to better cover areas of RH less than 30% and breezy afternoon winds to 15-20 mph. Across the Northeastern CONUS, weaker winds are expected D2/Wed, but another day of abnormally warm temperatures and lower afternoon RH may support elevated fire-weather potential given the lack of recent rainfall. The Elevated area was expanded into portions of DelMarVa to better overlap with receptive fuels. Otherwise, see the previous discussion for additional information. ..Lyons.. 06/06/2023 .PREV DISCUSSION... /ISSUED 0213 AM CDT Tue Jun 06 2023/ ...Synopsis... A positively tilted upper trough will meander over the Northeast while an upper trough across the Southwest diminishes through the day tomorrow/Wednesday. Dry and occasionally breezy conditions may occur across southern Arizona into far southwest New Mexico. However, the diminishing of the upper trough suggests that the surface winds should be weak compared to Day 1, with Elevated highlights withheld this outlook. Elevated highlights have been introduced from Lower Michigan into New Jersey again as dry northwesterly surface flow beneath the upper trough should persist. Since appreciable rainfall is not expected with the potentially dry thunderstorms on Day 1, fuels should remain largely receptive to fire spread. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0259 Status Updates
STATUS REPORT ON WW 259 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..KERR..06/05/23 ATTN...WFO...BRO... STATUS REPORT FOR WS 259 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC047-061-215-247-261-427-489-052240- TX . TEXAS COUNTIES INCLUDED ARE BROOKS CAMERON HIDALGO JIM HOGG KENEDY STARR WILLACY GMZ130-132-135-150-155-052240- CW . ADJACENT COASTAL WATERS INCLUDED ARE LAGUNA MADRE FROM THE PORT OF BROWNSVILLE TO THE ARROYO COLORADO LAGUNA MADRE FROM THE ARROYO COLORADO TO 5 NM NORTH OF PORT MANSFIELD TX LAGUNA MADRE FROM 5 NM NORTH OF PORT MANSFIELD TO BAFFIN BAY TX COASTAL WATERS FROM PORT MANSFIELD TX TO THE RIO GRANDE RIVER OUT 20 NM Read more

WW 259 SEVERE TSTM TX CW 051830Z - 052300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 259 NWS Storm Prediction Center Norman OK 130 PM CDT Mon Jun 5 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Deep South Texas Coastal Waters * Effective this Monday afternoon and evening from 130 PM until 600 PM CDT. * Primary threats include... Isolated significant damaging wind gusts to 75 mph possible Isolated very large hail events to 2 inches in diameter possible A tornado or two possible SUMMARY...A few supercells may develop and consolidate into a southward-moving cluster that spreads towards and across the Rio Grande this afternoon. The severe thunderstorm watch area is approximately along and 60 statute miles east and west of a line from 70 miles north of Mcallen TX to 40 miles east southeast of Mcallen TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU9). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 34025. ...Grams Read more

MD 0939 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF NORTHERN CA
Mesoscale Discussion 0939 NWS Storm Prediction Center Norman OK 0326 PM CDT Mon Jun 05 2023 Areas affected...Parts of northern CA Concerning...Severe potential...Watch unlikely Valid 052026Z - 052230Z Probability of Watch Issuance...5 percent SUMMARY...Storms capable of localized strong/severe gusts and perhaps some hail may increase through the afternoon. DISCUSSION...Despite generally limited low-level moisture, strong diurnal heating has resulted in modest destabilization across parts of northern CA, with MLCAPE increasing to near or above 500 J/kg. Widely scattered thunderstorms have already initiated, and additional development is expected through the remainder of the afternoon, especially across terrain-favored areas. Deep-layer shear will remain relatively weak, but midlevel easterly flow to the north of a mid/upper-level low near the coast of southern CA will support westward-moving cells/clusters through the afternoon. Steep midlevel lapse rates will support isolated hail potential with initial storm development across relatively higher elevation areas. With very steep low-level lapse rates, some threat for localized strong/severe gusts will accompany any stronger outflow-driven clusters that spread into the lower elevations. The severe threat is expected to remain too marginal and isolated for watch issuance. ..Dean/Grams.. 06/05/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...REV...MFR...STO...EKA... LAT...LON 41452364 41982231 41862089 41142046 40312010 39902042 39722101 39602210 39482326 39922370 40992394 41452364 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Mon Jun 05 2023 Valid 052000Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER DEEP SOUTH TEXAS... ...SUMMARY... Isolated severe thunderstorms with damaging winds and large hail are possible across several areas of the country this afternoon and evening. The most likely corridor for severe storms appears to be over Deep South Texas through this afternoon into the evening. ...20Z Update... Overall forecast outlined in the previous outlook remains valid. Thunderstorms remain possible across a large portion of the CONUS, with pockets of stronger storms possible over the southern Appalachians and Carolina Piedmont, the Sierra and central valley of CA, western MT, south FL and south TX. Each of these areas is addressed in the discussion appended below. Greatest severe coverage is still expected across south TX, where a few supercells have developed along the outflow boundary moving westward across the region. ..Mosier.. 06/05/2023 .PREV DISCUSSION... /ISSUED 1126 AM CDT Mon Jun 05 2023/ ...Deep South TX... Scattered thunderstorms are ongoing over the northwest Gulf to the Corpus Christi vicinity of the TX Coastal Plain near a minor mid/upper trough. On the backside of this trough, a belt of enhanced mid-level northwesterlies (near 40 kts at 500-mb per 12Z BRO sounding) will slacken through this afternoon. This flow regime should remain sufficient for potential supercell development towards the Lower Rio Grande Valley where low to mid 70s surface dew points and nearly full insolation are prevalent. With minimal MLCIN amid modest mid-level lapse rates, 12Z HREF members (outside of the HRRR) and the RRFS are fairly consistent in backbuilding convection across Deep South TX through late afternoon. A south-moving cluster with embedded supercells may develop with a threat for both severe hail and wind until convection spreads into Tamaulipas by early evening. ...Southern Appalachians/Piedmont... A deep upper low will persist off the New England Coast today. Peripheral influence of this low will maintain a belt of enhanced mid-level north-northwesterlies extending to the southern Appalachians through this evening. This will overlap with the eastern extent of the surface-based instability plume from the TN Valley/Deep South. Pervasive low clouds adjacent to the high terrain should gradually decrease through the day, with convective initiation likely to begin over the high terrain where breaks are already evident. Isolated to scattered thunderstorms will develop and attempt to spread southeast, but may tend to weaken with southeast extent in the Carolinas and backbuild west given the orientation of the instability plume. This should result in a corridor of isolated damaging wind and severe hail during the late afternoon to early evening focused along the lee of the high terrain. ...CA... An upper low spinning off the southern CA Coast should gradually shift inland north of the L.A. Basin by early morning. While its attendant strong mid-level jet will remain confined south of the border over Baja CA, a belt of enhanced south to southeasterlies will curl around the east to northeast semi-circle of the trough. Isolated to scattered thunderstorms are most likely over the Sierra NV towards the higher terrain of northern CA and separately towards the western portion of the Transverse Ranges in southern CA where upslope flow will occur. Steep low to mid-level lapse rates will support an isolated threat for severe wind and hail, mainly during the late afternoon and evening. ...South FL... 30-40 kt mid-level westerlies should persist across the southern third of the peninsula downstream of the minor mid/upper trough over the western Gulf. With generally northeasterly surface winds, weak flow through 3 km, and some backing of winds in the mid to upper levels, mid-level updraft rotation will probably remain relatively transient. Given the strength of the mid-level flow, a few of the stronger cells might produce marginally severe wind and hail during the late afternoon to early evening. ...Western MT... A minor mid-level impulse will continue to drift north from ID into northwest MT. Its attendant cloudiness this morning will slow diabatic heating immediately ahead of it near the ID/MT border, but more robust boundary-layer warming will occur farther downstream in parts of western to north-central MT. With just modest enhancement to mid-level southerlies, effective bulk shear will remain subdued from 20-30 kts. In addition, modest mid-level lapse rates will further temper updraft acceleration. Overall severe threat appears rather marginal, but a few severe wind and hail events may occur. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0222 PM CDT Mon Jun 05 2023 Valid 061200Z - 071200Z ...Great Lakes and Northeast... Confidence has increased that low-level wind fields will strengthen in the wake of the backdoor cold front moving through the eastern US. Aided by stronger flow aloft on the backside of the lingering upper trough, occasional gusts to 15-20 mph are possible across portions of lower MI, northern OH, PA and into portions of NY and NJ D2/Tuesday. With abnormally warm temperatures expected to continue, afternoon RH values of 25-35% will aid in the drying of area fuels. The dry and breezy conditions will support a few hours of elevated fire-weather potential across the Great Lakes and northeastern CONUS. ..Lyons.. 06/05/2023 .PREV DISCUSSION... /ISSUED 0152 AM CDT Mon Jun 05 2023/ ...Synopsis... The upper pattern for tomorrow/Tuesday will be quite similar to Day 1, with mid-level troughs meandering over the Southwest and Northeast. The trough over the Southwest will support 15 mph sustained southwesterly surface winds coinciding with 10-15 percent RH for at least a few hours tomorrow afternoon, warranting Elevated highlights for parts of southern Arizona into southwest New Mexico. Dry northerly surface flow will occur yet again over the Ohio Valley into the Northeast. Still, forecast surface wind speeds appear too low to address with fire weather highlights this outlook, with wildfire-spread potential expected to remain localized. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sun Jun 4 22:19:01 UTC 2023.

No Mesoscale Discussions are in effect as of Sun Jun 4 22:19:01 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0244 PM CDT Sun Jun 04 2023 Valid 042000Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS SOUTH TEXAS...PARTS OF THE SOUTHERN APPALACHIANS TO TENNESSEE VALLEY...AND SOUTH-CENTRAL LOUISIANA... ...SUMMARY... Isolated severe thunderstorms are possible across south Texas, parts of the southern Appalachians to Tennessee Valley, and south-central Louisiana into this evening. ...20Z Update... ...South-Central LA... Temperatures have climbed into the upper 80s and low 90s across south-central LA, amid dewpoints in the upper 60s. Thunderstorms have developed in the BTR vicinity, and are moving westward/southwestward into the steep low-level lapse rates environment downstream. As a result, there appears to be a corridor of slightly greater risk for damaging gusts over this area. ...South TX... As mentioned in MCD #935 and the previous outlook, isolated severe storms are possible later this afternoon across south TX. Destabilization continues south and west of an MCV (and associated cloud cover), with thunderstorm initiation ongoing on remnant outflow from south of JCT to HDO to about 20 miles west of SAT. Another outflow boundary, this one oriented more north to south, extends from near HDO southward/south-southeastward through ALI. Cumulus is building along this boundary as well, with additional thunderstorms possible here as well. Moderate buoyancy and modest shear could support of a few more robust updrafts, which could produce hail and localized severe gusts. ...Southern Appalachians to TN Valley... Overall storm coverage is still expected to increase across the region over the next few hours, with several multicell clusters possible. Earlier cloud cover has tempered heating across northern GA and adjacent portions of southeastern TN, limiting heating and keeping low-level lapse rates modest. However, skies and clearing and the resultant heating could steepen low-level lapse rates enough to support a few damaging gusts. Steep low-level lapse rates are already in place across western and middle TN, where additional storm development in ongoing. Damaging gusts are possible with these storms as well. ..Mosier.. 06/04/2023 .PREV DISCUSSION... /ISSUED 1117 AM CDT Sun Jun 04 2023/ ...South TX... In the wake of several clusters that resulted in extensive convective overturning yesterday afternoon through last night, appreciable buoyancy (MLCAPE in excess of 2000 J/kg) should largely be confined to south TX later this afternoon. With minimal large-scale ascent and light low-level winds through tonight, convective development appears ill-defined, but may be initially focused to the south of a remnant MCV in central TX. 20-30 kt mid-level northwesterlies should offer adequate deep shear to support a few transient supercells and multicell clustering. Amid more moderate mid-level lapse rates compared to yesterday, isolated severe hail and wind will be possible into this evening. ...Southern Appalachians to TN Valley... A belt of 15-25 kt mid-level north-northeasterlies will persist across the WV portion of the Appalachians owing to peripheral influence of a quasi-stationary mid/upper low near the New England coast. This should be adequate to support small to marginally severe hail in isolated storms that form in and south of this region, along with locally strong gusts later this afternoon. Farther west-southwest, weak deep-layer shear will mitigate organized severe storms, but sporadic microbursts will remain possible where moderate buoyancy can develop. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0244 PM CDT Sun Jun 04 2023 Valid 042000Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS SOUTH TEXAS...PARTS OF THE SOUTHERN APPALACHIANS TO TENNESSEE VALLEY...AND SOUTH-CENTRAL LOUISIANA... ...SUMMARY... Isolated severe thunderstorms are possible across south Texas, parts of the southern Appalachians to Tennessee Valley, and south-central Louisiana into this evening. ...20Z Update... ...South-Central LA... Temperatures have climbed into the upper 80s and low 90s across south-central LA, amid dewpoints in the upper 60s. Thunderstorms have developed in the BTR vicinity, and are moving westward/southwestward into the steep low-level lapse rates environment downstream. As a result, there appears to be a corridor of slightly greater risk for damaging gusts over this area. ...South TX... As mentioned in MCD #935 and the previous outlook, isolated severe storms are possible later this afternoon across south TX. Destabilization continues south and west of an MCV (and associated cloud cover), with thunderstorm initiation ongoing on remnant outflow from south of JCT to HDO to about 20 miles west of SAT. Another outflow boundary, this one oriented more north to south, extends from near HDO southward/south-southeastward through ALI. Cumulus is building along this boundary as well, with additional thunderstorms possible here as well. Moderate buoyancy and modest shear could support of a few more robust updrafts, which could produce hail and localized severe gusts. ...Southern Appalachians to TN Valley... Overall storm coverage is still expected to increase across the region over the next few hours, with several multicell clusters possible. Earlier cloud cover has tempered heating across northern GA and adjacent portions of southeastern TN, limiting heating and keeping low-level lapse rates modest. However, skies and clearing and the resultant heating could steepen low-level lapse rates enough to support a few damaging gusts. Steep low-level lapse rates are already in place across western and middle TN, where additional storm development in ongoing. Damaging gusts are possible with these storms as well. ..Mosier.. 06/04/2023 .PREV DISCUSSION... /ISSUED 1117 AM CDT Sun Jun 04 2023/ ...South TX... In the wake of several clusters that resulted in extensive convective overturning yesterday afternoon through last night, appreciable buoyancy (MLCAPE in excess of 2000 J/kg) should largely be confined to south TX later this afternoon. With minimal large-scale ascent and light low-level winds through tonight, convective development appears ill-defined, but may be initially focused to the south of a remnant MCV in central TX. 20-30 kt mid-level northwesterlies should offer adequate deep shear to support a few transient supercells and multicell clustering. Amid more moderate mid-level lapse rates compared to yesterday, isolated severe hail and wind will be possible into this evening. ...Southern Appalachians to TN Valley... A belt of 15-25 kt mid-level north-northeasterlies will persist across the WV portion of the Appalachians owing to peripheral influence of a quasi-stationary mid/upper low near the New England coast. This should be adequate to support small to marginally severe hail in isolated storms that form in and south of this region, along with locally strong gusts later this afternoon. Farther west-southwest, weak deep-layer shear will mitigate organized severe storms, but sporadic microbursts will remain possible where moderate buoyancy can develop. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0218 PM CDT Sun Jun 04 2023 Valid 051200Z - 061200Z ...Lower Colorado River Basin... The Elevated area was expanded westward where stronger surface winds and lower afternoon RH should overlap with pockets of better fuels in the lower deserts D2/Monday afternoon. Elevated meteorological conditions will also be possible across portions of northern AZ into the southern Great Basin, but area fuels remain mostly unfavorable for more widespread fire-weather concerns. See the previous discussion for more information. ..Lyons.. 06/04/2023 .PREV DISCUSSION... /ISSUED 0200 AM CDT Sun Jun 04 2023/ ...Synopsis... An upper trough will persist across the Northeast while a second mid-level trough impinges on the Southwest States tomorrow/Monday. Surface high pressure will continue across the Great Lakes area, fostering dry northeasterly flow amid curing fuels (given the lack of recent or forecast appreciable rainfall). However, the lack of stronger surface wind speeds suggests that wildfire-spread potential should remain localized. Elevated highlights may be introduced in future outlooks pending stronger surface winds via guidance consensus. Across the lower Colorado River Basin, 15+ mph sustained southerly winds amid 15 percent RH are likely by afternoon peak heating, driven by a mixing boundary layer and the approach of the upper trough. Elevated highlights have been added where the aforementioned favorable surface winds/RH will overlap with dry fuels supporting wildfire spread. Like Day 1, dry conditions will also exist across portions of the Great Basin into the Pacific Northwest (to the lee of the Cascades), where fuels continue to cure. However, the lack of a stronger surface wind field precludes fire weather highlights. ...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 0218 PM CDT Sun Jun 04 2023 Valid 051200Z - 061200Z ...Lower Colorado River Basin... The Elevated area was expanded westward where stronger surface winds and lower afternoon RH should overlap with pockets of better fuels in the lower deserts D2/Monday afternoon. Elevated meteorological conditions will also be possible across portions of northern AZ into the southern Great Basin, but area fuels remain mostly unfavorable for more widespread fire-weather concerns. See the previous discussion for more information. ..Lyons.. 06/04/2023 .PREV DISCUSSION... /ISSUED 0200 AM CDT Sun Jun 04 2023/ ...Synopsis... An upper trough will persist across the Northeast while a second mid-level trough impinges on the Southwest States tomorrow/Monday. Surface high pressure will continue across the Great Lakes area, fostering dry northeasterly flow amid curing fuels (given the lack of recent or forecast appreciable rainfall). However, the lack of stronger surface wind speeds suggests that wildfire-spread potential should remain localized. Elevated highlights may be introduced in future outlooks pending stronger surface winds via guidance consensus. Across the lower Colorado River Basin, 15+ mph sustained southerly winds amid 15 percent RH are likely by afternoon peak heating, driven by a mixing boundary layer and the approach of the upper trough. Elevated highlights have been added where the aforementioned favorable surface winds/RH will overlap with dry fuels supporting wildfire spread. Like Day 1, dry conditions will also exist across portions of the Great Basin into the Pacific Northwest (to the lee of the Cascades), where fuels continue to cure. However, the lack of a stronger surface wind field precludes fire weather highlights. ...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 1215 PM CDT Sun Jun 04 2023 Valid 051200Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE WESTERN CAROLINAS AND NORTHEAST GEORGIA... ...SUMMARY... Isolated strong to severe thunderstorms may occur Monday across western portions of Carolinas and northeast Georgia. Both occasional damaging winds and hail appear possible. ...Synopsis... An expansive anticyclone is forecast to remain centered near the southern Saskatchewan/Manitoba border throughout the day Monday, with its influence stretching through the Upper Midwest into the northern and central Plains. Upper troughing is anticipated east of this anticyclone, extending from Quebec through the Northeast into the Mid-Atlantic. A shortwave trough is expected to move through this troughing, from the Lower Great Lakes region across the Mid/Upper OH Valley and into the Mid-Atlantic. A pair of upper lows are anticipated west of the anticyclone, one over British Columbia and the other just off the southern CA Coast. The surface pattern will likely be void of any well-defined features, with generally modest winds across much of the central and eastern CONUS. The only exception in across the High Plains in the vicinity of the lee trough. Somewhat stronger flow is possible from southern CA into NV and western AZ. Low-level moisture will remain within the southern and western periphery of the surface ridging, i.e. from the Southeast across the Lower MS Valley and into the southern and central Plains. Scattered to numerous thunderstorms are forecast during the afternoon and evening in these areas, but weak shear should foster a mainly multicellular mode across the majority of the region, limiting the severe potential. ...Carolinas and Northeast GA... The best overlap between buoyancy, moderate flow aloft, and forcing for ascent is anticipated from the western Carolinas into northeast GA, ahead of the subtle shortwave trough. A mix of multicells and perhaps a marginal supercell or two appears possible, with a corresponding risk for isolated hail and damaging winds. This activity should generally spread southeastward through early Monday evening before weakening. ...Central ID into western MT... With the region oriented between the anticyclone to its east and upper troughing across British Columbia, slightly stronger mid-level flow is anticipated from central/eastern ID into western MT on Monday. Modest buoyancy is anticipated as well, with afternoon/evening thunderstorms expected. Given the slightly stronger mid-level flow, potential exists for a strong storm or two. However, the overall severe threat will be mitigated by the limited buoyancy. ...Northern CA/Southern OR... High-based thunderstorms will likely move westward across the region throughout the afternoon and evening, fostered by increased mid-level moisture and orographically enhanced ascent. Shear will be weak, but the high-based character of these storms amid the well-mixed boundary layer may result in a few strong downbursts, particularly over lower elevations. ..Mosier.. 06/04/2023 Read more

No watches are valid as of Sat Jun 3 22:16:02 UTC 2023.

No Mesoscale Discussions are in effect as of Sat Jun 3 22:16:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0237 PM CDT Sat Jun 03 2023 Valid 032000Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER RIO GRANDE VALLEY IN SOUTH TX... ...SUMMARY... A swath of severe wind gusts may occur between about 8 PM to Midnight CDT along a portion of the Lower Rio Grande Valley. Otherwise, isolated severe thunderstorms with wind and hail will be possible across parts of the south-central and northeastern states, mainly through this evening. ...20Z Update... ...Far eastern NM to South TX... Thunderstorm initiation has already occurred across the higher terrain, with deepening cumulus along the lee trough as well. Expectation is for these storms to move eastward over time, posing a threat for isolated severe gusts and perhaps a few instances of hail. Cumulus is deepening just south of SJT as well, along a remnant outflow boundary. Continued development is anticipated, with scattered thunderstorm coverage likely by the late afternoon. Shear is limited, but strong buoyancy is in place, supporting the potential for robust updrafts capable of hail and damaging gusts. ...Lower Rio Grande Valley... Conditional scenario outlined in the previous discussion still appears plausible this evening and overnight, with recent CAM solutions contributing to its validity. Expectation is for persistent development over the higher terrain of Coahuila to eventually move eastward as an MCS. This supports continuing the 15% wind across the RGV. ...Mid-Atlantic/Central Appalachians/Upper OH Valley... Thunderstorms initiated a few hours ago along a southward/southwestward progressing cold front moving through central PA. A few stronger storms are possible within the eastern periphery of this region, particularly eastern PA, where slightly stronger flow overlays the unstable airmass. Mesoanalysis indicates effective shear of 30-40 kt across this region. Flow weakens with westward extent and storms will tend to be more disorganized within this weakly sheared environment. Even so, sufficient buoyancy and steep low-level lapse rates may support localized downbursts and small to briefly severe hail. ...Arklatex to Southern LA... As mentioned in MCD #931, a Marginal risk for hail and gusty winds remains through the afternoon from the Arklatex into southern LA. Moderate buoyancy is in place, but weak shear should limit storm organization and strength. Isolated gusty winds and hail are the primary severe threat. ..Mosier.. 06/03/2023 .PREV DISCUSSION... /ISSUED 1125 AM CDT Sat Jun 03 2023/ ...Far eastern NM to south TX... An elongated, low-amplitude upper trough will stay anchored from the Great Basin to the southern High Plains through tonight. The attendant belt of moderate mid-level westerlies will largely remain confined across northern Mexico into Deep South TX. Several areas of isolated to scattered thunderstorm development are expected later this afternoon into the evening: 1) the higher terrain of northern Coahuila into perhaps the Big Bend, 2) a remnant outflow boundary over the Concho Valley, and 3) the far eastern NM/west TX border area from the Raton Mesa to the Permian Basin. Areas to the north of south TX will be in a more modest deep-layer shear environment with effective values around 20-30 kt. This should generally support weak and transient mid-level updraft rotation and multicell clustering. Owing to continued steep mid-level lapse rates, large hail and severe wind gusts will be possible with overall coverage expected to remain isolated. A relatively greater but largely conditional severe threat may occur over a portion of the Rio Grande Valley in south TX later this evening if supercell clusters over Coahuila can develop an adequate cold pool prior to the nocturnal increase in MLCIN. The 14Z HRRR is the most insistent of morning CAMs with its depiction of an MCS moving east of the international border. Guidance is fairly consistent that negative low-level theta-e advection will shift west from the northwest Gulf across Deep South TX tonight, likely yielding weakening of convection as it spreads farther east of the Rio Grande. ...Mid-Atlantic/Central Appalachians/Upper OH Valley... Isolated to scattered thunderstorms should develop along a west to southwest-moving cold front, with initial development expected in PA based on a swelling cu field already. A pocket of moderate buoyancy with MLCAPE of 1000-1500 J/kg will similarly form just ahead of this portion of the front. Guidance suggests there may be a belt of somewhat greater north-northeasterly mid-level winds in the eastern PA vicinity. But the lack of a 12Z ALB observed sounding or VWP data high enough to sample this lowers overall confidence. CAM guidance does suggest that a couple of southwest-moving cells that initiate in this region may contain mid-level updraft rotation which could result in a meso-beta corridor of relatively greater hail and wind potential. Elsewhere, weaker deep-layer shear and buoyancy will serve to limit potential to locally strong gusts from sporadic microbursts amid steep low-level lapse rates and a relatively deep mixed boundary layer. ...Ark-La-Tex to south LA... Scattered to widespread thunderstorms are expected later this afternoon within a moderately buoyant and weakly sheared environment. The strongest storms will be capable of locally strong wind gusts. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0214 PM CDT Sat Jun 03 2023 Valid 041200Z - 051200Z ...NO CRITICAL AREAS... ...Great Lakes and Ohio Valley... A few hours of modestly dry and breezy conditions may develop D2/Sunday afternoon in the wake of a backdoor cold front moving through portions of the Midwest. Area forecast soundings show surface winds of 10-15 mph may briefly overlap with afternoon RH values below 35% across portions of the OH Valley and southern Great Lakes. Despite relatively dry conditions over the preceding days, area fuels remain largely unreceptive to fire spread. While some drying of area fuels will likely occur, the lack of more robust fuels suggests widespread fire-weather concerns are low. Please see the previous discussion for more information. ..Lyons.. 06/03/2023 .PREV DISCUSSION... /ISSUED 0133 AM CDT Sat Jun 03 2023/ ...Synopsis... A benign upper pattern will remain in place across the CONUS tomorrow, with moist low-level conditions and weak surface winds limiting widespread, significant wildfire-spread potential across most the CONUS. Seasonably dry low-level air will continue to meander over the Southwest, but wildfire-spread potential should remain localized, given weak surface winds. The latest guidance consensus also depicts some overlap of dry, occasionally breezy conditions across portions of Pennsylvania toward Lower Michigan and the Ohio Valley. However, modest surface winds and fuel receptiveness suggest wildfire-spread potential should be localized at best. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No Mesoscale Discussions are in effect as of Fri Jun 2 22:16:08 UTC 2023.

WW 0255 Status Updates
STATUS FOR WATCH 0255 HAS NOT BEEN ISSUED YET Read more