Severe Storms

No watches are valid as of Thu Jun 8 21:48:02 UTC 2023.

No Mesoscale Discussions are in effect as of Thu Jun 8 21:48:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Thu Jun 08 2023 Valid 082000Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH THIS EVENING FOR PARTS OF SOUTH CENTRAL AND SOUTHEAST TX... ...SUMMARY... The most likely corridor for large hail and isolated damaging winds will be across a portion of southeast Texas into early evening. ...South central/southeast TX through this evening... Convection is ongoing from just east of San Antonio to north/northeast of College Station. The somewhat stronger vertical shear and potential for more organized/supercell storms with large hail will remain from the San Antonio cluster southeastward, in association with a remnant MCV. Farther northeast, weaker vertical shear suggests more pulse-type storms into southeast TX, where isolated wind damage and large hail may occur for the next few hours. ...ND area this afternoon through tonight... Convection is forming this afternoon along a wind shift/front across west central ND. Flow is weak over this area near the midlevel ridge, but moderate-strong buoyancy (MLCAPE near or above 2000 J/kg) and midlevel lapse rates near 7 C/km will support the threat for occasional strong-severe gusts and isolated large hail with multicell clusters that will spread slowly east/southeastward through tonight. ...South GA and vicinity the remainder of the afternoon... Storm coverage is expected to remain rather isolated, given weak forcing for ascent and relatively dry midlevel air. However, a few storms remain possible along a weak front from southern SC across south GA and far north FL. Moderate buoyancy and rather weak vertical shear will primarily support multicell storms with a marginal wind threat. Slightly stronger vertical shear is present near the front across southern SC, where isolated large hail may also occur. ..Thompson.. 06/08/2023 .PREV DISCUSSION... /ISSUED 1129 AM CDT Thu Jun 08 2023/ ...Southeast TX... An MCV over central TX will track southeast off the Upper TX Gulf Coast this evening. Nearly full insolation will occur ahead of the MCV coincident with upper 60s to low 70s surface dew points which persist north of an MCS that tracked across Deep South TX earlier this morning. This should yield a pocket of moderately large buoyancy with MLCAPE reaching 2000-3000 J/kg at peak heating. Consensus of CAM guidance suggests isolated thunderstorms should develop ahead of the MCV, with the 12Z WRF-NSSL indicative of at least scattered coverage which would typically be expected with an MCV. Guidance generally indicates slight mid-level warming in forecast soundings which may explain the tendency for more isolated coverage in most CAMs. A belt of enhanced mid-level northwesterlies from 30-40 kt should be relegated to south-central TX and the Middle/Lower TX Gulf Coast. A relatively confined overlap of favorable CAPE/shear space should occur in a portion of southeast TX. With minimal 0-3 km SRH, updraft rotation should be limited to the mid-levels. Main threat will be large hail along with isolated damaging winds until convection moves offshore this evening. ...South GA/SC and north FL... A slowly southward-sagging surface cold front will serve as a focus for at least isolated thunderstorms later this afternoon across parts of the Southeast. West-southwesterly low-level flow will persist ahead of the front similar to yesterday, but mid-level westerlies will be stronger today owing to a jet arcing across the southern Appalachians and the NC/SC border area. This should compensate for weak mid-level lapse rates and may yield small to marginally severe hail over the Lower Savannah Valley. Otherwise, with nearly full insolation, steep low-level lapse rates will support potential for a primary threat of strong to marginally severe microbursts. ...Lower Mid-Atlantic Coast... Isolated, marginally severe hail and locally strong gusts should persist through the mid-afternoon until lower-topped, frontal-forced thunderstorms move offshore. A pocket of steeper 850-600 mb lapse rates in conjunction with an elongated hodograph in the upper portion of the buoyancy profile will support small to marginally severe hail production. This may enhance downdraft potential over the Delmarva peninsula where boundary-layer heating is relatively greater and yield locally strong surface gusts despite weak low-level flow. For additional information, please see MCD 952. ...Northern Great Plains... An upper ridge persists across the central Great Plains northwestward into eastern MT. With 60-64 F boundary-layer dew points, an arc of moderately large buoyancy with 2000-3000 J/kg of MLCAPE will develop from parts of eastern MT to the eastern Dakotas. Deep-layer shear will be rather weak, especially within the axis of the mid-level ridge, suggesting that slow-moving, pulse storms will dominate. 15-25 kt effective bulk shear may develop across parts of central to eastern ND where light low-level southeasterlies persist beneath modest mid to upper-level west-northwesterlies. In this regime, sporadic occurrences of isolated severe wind gusts and large hail should peak in the late afternoon to early evening, before waning after sunset. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Thu Jun 08 2023 Valid 091200Z - 101200Z No Changes; see the previous discussion for more information. ..Lyons.. 06/08/2023 .PREV DISCUSSION... /ISSUED 1244 AM CDT Thu Jun 08 2023/ ...Synopsis... The mid-level trough on the East Coast will begin to eject into the Atlantic as a mid-level impulse overspreads the Desert Southwest tomorrow/Friday. Dry air will continue to meander around the Ohio/Tennessee Valleys and points eastward to the Carolina Piedmont, but with weak surface wind fields. The lack of stronger surface winds suggests that fire-weather spread potential should remain more localized. As the western upper-level impulse overspreads the Southwest, boundary-layer mixing will encourage dry and breezy conditions across portions of southern New Mexico into Far West Texas. 15 mph sustained westerly surface flow is forecast to overlap with 10-15 percent RH for at least a few hours, warranting the introduction of Elevated highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0145 PM CDT Thu Jun 08 2023 Valid 101200Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN PLAINS INTO THE ARK-LA-MISS... AMENDED TO ACCOUNT FOR EVOLUTION OF EARLY CONVECTION ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and severe/damaging winds should occur Saturday across parts of the southern Plains into the Ark-La-Miss. ...Updated discussion... A storm cluster and associated MCV are expected to be ongoing in the vicinity of central OK Saturday morning. The convection will likely persist through the day while spreading east-southeastward toward the ArkLaTex and the Ark-La-Miss regions, with an accompanying threat for damaging winds. Outflow with the MCS will likely spread southward into TX, and potentially provide a focus for additional thunderstorm development during the afternoon/evening. Storms along the outflow, especially if it can stall by mid-late afternoon, will have the potential to be supercells capable of producing isolated very large hail. The potential for additional diurnal development in northwest OK and KS, in the wake of the morning convection, is highly uncertain. Given background shortwave ridging, plus subsidence in the wake of the MCV, the potential for severe storms appears limited at best. --Previous discussion below issued at 0730z-- ...Southern Plains into the ArkLaTex... Associated with modest low-level warm advection, mainly elevated thunderstorms may be ongoing at the start of the period Saturday morning across parts of OK towards the Ozarks. With steep mid-level lapse rates present and ample MUCAPE available, this convection may pose an isolated threat for severe hail Saturday morning. This activity may produce an outflow boundary, which could provide a focus for renewed thunderstorm development across parts of OK Saturday afternoon. A low-amplitude shortwave trough is forecast to continue moving eastward across the southern Plains through the period. A surface dryline should mix eastward across TX by late Saturday afternoon. This boundary should also provide a focus for severe thunderstorms. Convective evolution remains somewhat uncertain through the day due to the influence of morning thunderstorms, and weak large-scale ascent associated with the shortwave trough. Regardless, ample daytime heating of a moist low-level airmass east of the dryline should foster moderate to strong MLCAPE by late afternoon. Any convection that can initiate along the dryline will likely become severe. Somewhat elongated/straight hodographs at mid/upper levels and steep mid-level lapse rates should support an isolated threat for very large hail with any discrete thunderstorms that initially develop. The potential for one or more convective clusters/MCSs is less clear, but still possible. Some guidance suggests that robust thunderstorms will develop on the southern flank of the morning convection, and subsequently spread east-southeastward across the ArkLaTex vicinity and eventually lower MS Valley. A destabilizing airmass ahead of this possible MCS would support some threat for damaging winds. The Slight Risk has been expanded eastward to account for this potential. Otherwise, discrete thunderstorms may grow upscale into an MCS Saturday evening as a low-level jet modestly strengthens. This convection may also pose a threat for severe/damaging winds as it moves eastward. ..Thompson.. 06/08/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Thu Jun 08 2023 Valid 091200Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FRIDAY AFTERNOON THROUGH LATE EVENING FROM SOUTHEAST CO INTO SOUTHWEST KS AND THE OK PANHANDLE... ...SUMMARY... A few severe outflow gusts will be possible late Friday afternoon/evening from southeast Colorado into southwest Kansas and the Oklahoma Panhandle. ...Great Plains Friday afternoon into Friday night... A midlevel trough will persist over the Northeast, with an associated threat for diurnal convection with the midlevel cold pool. Farther west, weak ridging aloft will persist over the High Plains, with a weak trough over the Great Basin. A weak southern stream will remain across NM, and an embedded speed maximum will eject northeastward by Friday evening. Lingering low-level moisture and modestly steep midlevel lapse rates will result in moderate buoyancy across much of the Plains tomorrow afternoon. A somewhat better focus for thunderstorm development will be in the immediate lee of the higher terrain across southeast CO tomorrow afternoon/evening, downstream from the weak ejecting trough. The storm environment will support a mix of multicell clusters and marginal supercells initially, given MLCAPE of 1000-2000 J/kg and relatively straight hodographs with effective bulk shear near 30 kt. Storms should grow upscale during the evening through outflow interactions, and a cluster is expected to move southeastward toward southwest KS/OK Panhandle early Friday night. The strongest storms in the cluster could produce a few severe outflow gusts of 60-70 mph, along with isolated large hail. The storms will spread southeastward overnight into the main body of OK, though they should weaken during the early morning hours. Otherwise, isolated strong-severe storms may occur farther south along the dryline into parts of west TX, though storm coverage is a bit in question. Farther north, vertical shear will generally remain weak. However, there is the potential for an MCV to emerge across eastern SD early in the day, which will then move southward through the afternoon. Isolated strong-severe gusts and large hail may occur with the strongest storms with the MCV. ...FL tomorrow afternoon... A stalled front and local sea breeze circulations will help focus widely scattered to scattered thunderstorm development Friday afternoon across north FL and along the Atlantic coast in the westerly flow regime aloft. Moderate buoyancy and slightly enhanced vertical shear will favor a mix of multicell clusters and marginal supercells, with an attendant threat for isolated strong-severe outflow gusts and large hail. ..Thompson.. 06/08/2023 Read more

No watches are valid as of Wed Jun 7 22:10:02 UTC 2023.

MD 0948 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF SOUTHWESTERN TEXAS
Mesoscale Discussion 0948 NWS Storm Prediction Center Norman OK 0450 PM CDT Wed Jun 07 2023 Areas affected...portions of southwestern Texas Concerning...Severe potential...Watch unlikely Valid 072150Z - 072315Z Probability of Watch Issuance...20 percent SUMMARY...Occasional instances of severe hail and wind are possible with the stronger storms through the remainder of the afternoon into early evening. The severe threat is expected to remain isolated enough such that a WW issuance appears unlikely. DISCUSSION...Multiple multicell clusters and supercells have developed over the past hour across the TX Trans Pecos region. A mid-level shortwave trough and associated 7-8 C/km mid-level lapse rates continue to overspread upper 50s/low 60s F dewpoints, resulting in increasing buoyancy (1000+ J/kg MLCAPE) and deep-layer ascent to support the continued intensification of storms. Modest mid-level flow is also overspreading southwestern Texas, resulting in lengthy hodographs and accompanying 35-45 kts of effective bulk shear. Large hail may accompany the stronger storms, with severe gusts also possible (given the well-mixed boundary layer and 9+ C/km low-level lapse rates). However, the overall severe threat should remain relatively isolated and a WW issuance is not currently expected. ..Squitieri/Hart.. 06/07/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SJT...MAF...EPZ... LAT...LON 30250461 31060520 31520556 31900493 32030393 32000250 31530176 30970141 30410157 30080230 29910382 30250461 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Wed Jun 07 2023 Valid 072000Z - 081200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS SEVERAL AREAS OF THE CONUS... ...SUMMARY... Isolated severe thunderstorms with wind and hail remain possible in several areas of the country this afternoon and evening: the southern High Plains, the South Carolina vicinity, south to east Florida, the interior Northwest, and the eastern Dakotas. ...20Z Update... Some minor changes have been made to the general thunderstorm lines across NC/VA, but severe probabilities remain unchanged. The potential for a supercell or two late this afternoon into this evening remains evident across the TX Trans Pecos, with generally more disorganized threats scattered elsewhere across the CONUS. For more information regarding the short-term threats, see MCD 945 across Florida, MCD 946 across South Carolina, and MCD 947 across eastern NM into the TX Panhandle/South Plains. Also see the previous discussion below for more information. ..Dean.. 06/07/2023 .PREV DISCUSSION... /ISSUED 1128 AM CDT Wed Jun 07 2023/ ...Southern High Plains... A southern-stream upper jet will gradually expand east across much of northern Mexico. Within the left-exit region of this jet, isolated to scattered thunderstorms will develop over the higher terrain of the TX Trans-Pecos and eastern NM. Proximity of a low-amplitude mid-level ridge will yield weak deep-layer shear north of the Trans-Pecos, with the latter seeing strengthening flow during the late afternoon into the evening. Here, a couple supercells should form with a primary threat of isolated large hail before clustering towards the Rio Grande. Farther north, loosely organized multicell clusters should dominate with sporadic occurrences of severe hail and wind possible through early tonight. ...Southeast... Scattered thunderstorm development appears to be commencing across the south to eastern FL peninsula, with additional storms likely to form later this afternoon near a southward-sagging cold front in the SC vicinity. Belts of 30-40 kt west-southwesterlies will persist across central to south FL ahead of a low-amplitude trough over the east-central Gulf and along the frontal zone to the south of the amplified trough across the Northeast. While low-level flow will be weak over FL and predominately westerly over the SC vicinity, adequate effective bulk shear will exist for transient supercell and multicell structures capable of isolated damaging winds and lower-end severe hail. ...Northeast CA to southwest MT... A weakening upper low will drift northeast from southeast CA into southern NV. This will result in gradual decay of the mid-level wind field. However, adequate speed shear from the mid to upper levels should still support semi-organized multicell clustering later this afternoon, mainly across southern to eastern OR and the southern half of ID. Similar to yesterday, isolated severe wind gusts will be the primary threat, with small to marginally severe hail also possible. ...Eastern Dakotas... A mid to upper-level anticyclone will remain anchored over the central Dakotas. A pocket of moderate buoyancy should develop across a portion of the eastern Dakotas where boundary-layer dewpoints can hold from 60-64 F. While deep-layer flow will remain weak, directional change with height from light low-level south-southeasterlies to weak mid-level northerlies may yield a strip of 15-20 kt effective bulk shear. A few marginally severe wind and hail events from pulse to weakly organized multicells remain possible during the late afternoon to early evening. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0210 PM CDT Wed Jun 07 2023 Valid 081200Z - 091200Z ...NO CRITICAL AREAS... No changes; localized fire-weather conditions will remain possible across the Great Lakes D2/Thursday, but noticeably weaker winds should be less favorable for widespread fire concerns. See the previous discussion for more information. ..Lyons.. 06/07/2023 .PREV DISCUSSION... /ISSUED 1255 AM CDT Wed Jun 07 2023/ ...Synopsis... A mid-level trough will continue to slowly sag southward along the East Coast while weak, cyclonic upper flow will prevail across the western U.S. tomorrow/Thursday. Surface high pressure will dominate much of the central and eastern CONUS. Dry low-level air will continue to drift southward from the Ohio Valley/Mid Atlantic into the Tennessee Valley/Carolina Piedmont during the afternoon. At the moment, guidance consensus suggests that surface winds will be weak, with fire weather highlights withheld this outlook. Likewise, seasonably dry low-level air will meander across the Southwest, but the lack of an appreciable surface wind field precludes fire weather highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Tue Jun 6 22:12:02 UTC 2023.

MD 0944 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTH CAROLINA INTO EXTREME EASTERN GEORGIA
Mesoscale Discussion 0944 NWS Storm Prediction Center Norman OK 0455 PM CDT Tue Jun 06 2023 Areas affected...South Carolina into extreme eastern Georgia Concerning...Severe potential...Watch unlikely Valid 062155Z - 062330Z Probability of Watch Issuance...5 percent SUMMARY...Large hail and damaging gusts may accompany the stronger storms through the evening, with a gradual weakening trend likely after sunset. A WW issuance is not expected. DISCUSSION...Thunderstorms have been increasing in intensity across SC over the past hour or so, with MRMS mosaic radar data indicating 30 dBZ echo tops exceeding 45 kft and MESH showing hail approaching 1 inch in diameter. Shear across the region is poor, though mid 60s F surface dewpoints amid 8-9 C/km low-level lapse rates (per 21Z mesoanalysis) is contributing to 3000 J/kg SBCAPE. The stronger pulse storms will be capable of producing damaging gusts and perhaps an instance of severe hail. After sunset, nocturnal cooling should result in waning storm intensity. Nonetheless, the severe threat should remain isolated at best and a WW issuance is not expected. ..Squitieri/Kerr.. 06/06/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILM...CHS...CAE...GSP...FFC... LAT...LON 34748269 34898170 34657984 34297932 33667940 33027969 32658011 32368066 32208104 32258139 32928248 33738287 34748269 Read more

MD 0943 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF CENTRAL AND NORTHERN NEW MEXICO...FAR SOUTHEASTERN COLORADO
Mesoscale Discussion 0943 NWS Storm Prediction Center Norman OK 0331 PM CDT Tue Jun 06 2023 Areas affected...portions of central and northern New Mexico...far southeastern Colorado Concerning...Severe potential...Watch unlikely Valid 062031Z - 062230Z Probability of Watch Issuance...5 percent SUMMARY...Thunderstorms capable of hail and gusty winds possible through the afternoon. DISCUSSION...Thunderstorm development has been ongoing across portions of far eastern Arizona and New Mexico. A few of these storms have produced nickel to quarter size hail across eastern Arizona and northeastern New Mexico. Surface objective analysis indicates daytime heating yielding around 500-1500 J/kg MLCAPE atop steep lapse rates through the profile. Increasing southerly flow from a mid-level jet max across Arizona has led to around 20 kts of shear, which is largely speed shear as winds are uniform in direction with height. This environment will favor multi-cell clusters, a few of which may produce instances of severe hail and gusty winds. Weak shear for organization is expected to keep coverage of this threat too localized to warrant watch issuance. ..Thornton/Grams.. 06/06/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MAF...PUB...ABQ...EPZ... LAT...LON 35810577 36370543 36680528 37120485 37260471 37420443 37570405 37430317 37090314 35790322 35220332 33780435 33370443 32750495 32720496 32490615 32630654 33070726 33620774 33750811 33970856 34320870 34610885 35010888 35310879 35480871 35320801 35340698 35810577 Read more

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