Severe Storms

WW 0556 Status Updates
STATUS FOR WATCH 0556 HAS NOT BEEN ISSUED YET Read more

WW 556 SEVERE TSTM MI WI LM LS 272150Z - 280400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 556 NWS Storm Prediction Center Norman OK 450 PM CDT Thu Jul 27 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western Upper Michigan North-central and northeast Wisconsin Lake Michigan Lake Superior * Effective this Thursday afternoon and evening from 450 PM until 1100 PM CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 75 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Congealing clusters should spread east-southeast this evening with a threat for damaging winds and large hail. The severe thunderstorm watch area is approximately along and 80 statute miles east and west of a line from 35 miles north northwest of Marquette MI to 45 miles south southeast of Mosinee WI. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 553...WW 554...WW 555... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 29030. ...Grams Read more

MD 1742 CONCERNING SEVERE THUNDERSTORM WATCH 554... FOR PORTIONS OF EASTERN MN INTO NORTHERN/CENTRAL WI AND THE U.P. OF MI
Mesoscale Discussion 1742 NWS Storm Prediction Center Norman OK 0436 PM CDT Thu Jul 27 2023 Areas affected...Portions of eastern MN into northern/central WI and the U.P. of MI Concerning...Severe Thunderstorm Watch 554... Valid 272136Z - 272300Z The severe weather threat for Severe Thunderstorm Watch 554 continues. SUMMARY...The threat for large hail and damaging winds will likely spread eastward over the next couple of hours. Downstream watch issuance will likely be needed. DISCUSSION...Multiple supercells are ongoing this afternoon across parts of northwestern WI and east-central MN. Multiple measured severe hail reports of 1 to 2 inches have occurred with this activity. Recent radar trends show some updraft interactions, and the beginning stages of clustering/upscale growth may continue. Regardless, a continued threat for large to very large hail will persist in the short term, as strong instability (3000-3500+ J/kg of MLCAPE) and 40+ kt of deep-layer shear prove favorable for robust updrafts. A tornado also appears possible in the short term as well, mainly across northwestern WI where low-level shear is maximized in the presence of ongoing supercells. The threat for severe/damaging winds will likely increase this evening as thunderstorm clusters move eastward across northern/central WI and the U.P. of MI. The eastern extent of the severe threat remains somewhat unclear, as less instability is present towards Lake Michigan. Still, downstream Severe Thunderstorm Watch issuance will likely be required for the increasing hail/wind threat. ..Gleason/Grams.. 07/27/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MQT...GRB...DLH...ARX...MPX... LAT...LON 45399286 46119335 46859154 46878924 46508761 46018731 45228747 44478816 44459035 44729160 45399286 Read more

WW 0553 Status Updates
240- STATUS REPORT ON WW 553 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NE AVP TO 20 ESE MSV TO 15 NNE POU TO 20 W BDL TO 15 W ORH TO 15 N PSM TO 20 SSW AUG TO 20 NNE AUG. ..BENTLEY..07/27/23 ATTN...WFO...OKX...BOX...ALY...GYX...BGM... STATUS REPORT FOR WS 553 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS CTC001-003-005-007-009-011-013-015-272240- CT . CONNECTICUT COUNTIES INCLUDED ARE FAIRFIELD HARTFORD LITCHFIELD MIDDLESEX NEW HAVEN NEW LONDON TOLLAND WINDHAM MEC001-005-011-013-015-023-027-031-272240- ME . MAINE COUNTIES INCLUDED ARE ANDROSCOGGIN CUMBERLAND KENNEBEC KNOX LINCOLN SAGADAHOC WALDO YORK MAC005-009-013-015-017-021-023-025-027-272240- MA Read more

WW 553 SEVERE TSTM CT MA ME NH NY PA RI VT CW 271645Z - 280000Z
0- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 553 NWS Storm Prediction Center Norman OK 1245 PM EDT Thu Jul 27 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Connecticut Massachusetts Southern Maine Southern New Hampshire Southeast New York Northeast Pennsylvania Rhode Island Southern Vermont Coastal Waters * Effective this Thursday afternoon and evening from 1245 PM until 800 PM EDT. * Primary threats include... Scattered damaging winds likely with isolated significant gusts to 75 mph possible Isolated large hail events to 1 inch in diameter possible A tornado or two possible SUMMARY...Thunderstorms will intensify this afternoon along a cold front and spread eastward across the watch area. Damaging wind gusts will be possible with the strongest cells through the afternoon. A tornado or two cannot be ruled out. The severe thunderstorm watch area is approximately along and 90 statute miles east and west of a line from 5 miles west northwest of Augusta ME to 30 miles south of Poughkeepsie NY. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU3). 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 1 inch. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 26030. ...Hart Read more

WW 0554 Status Updates
STATUS REPORT ON WW 554 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 WNW BRD TO 25 E BRD TO 10 S DLH TO 30 ENE BFW. ..BENTLEY..07/27/23 ATTN...WFO...DLH...MPX... STATUS REPORT FOR WS 554 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC001-003-009-017-025-035-053-059-065-067-075-093-095-097-115- 123-141-145-153-163-171-272240- MN . MINNESOTA COUNTIES INCLUDED ARE AITKIN ANOKA BENTON CARLTON CHISAGO CROW WING HENNEPIN ISANTI KANABEC KANDIYOHI LAKE MEEKER MILLE LACS MORRISON PINE RAMSEY SHERBURNE STEARNS TODD WASHINGTON WRIGHT WIC003-005-007-013-017-031-033-035-051-093-095-099-107-109-113- 129-272240- WI . WISCONSIN COUNTIES INCLUDED ARE ASHLAND BARRON BAYFIELD BURNETT CHIPPEWA DOUGLAS DUNN EAU CLAIRE IRON PIERCE POLK PRICE Read more

WW 554 SEVERE TSTM MN WI LS 271905Z - 280200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 554 NWS Storm Prediction Center Norman OK 205 PM CDT Thu Jul 27 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Central and Eastern Minnesota Northwest Wisconsin Lake Superior * Effective this Thursday afternoon and evening from 205 PM until 900 PM CDT. * Primary threats include... Widespread large hail and isolated very large hail events to 3 inches in diameter likely Scattered damaging wind gusts to 70 mph likely A tornado or two possible SUMMARY...Thunderstorms will rapidly develop this afternoon over central Minnesota and track southeastward across the watch area. Very large hail and damaging winds will be possible. The severe thunderstorm watch area is approximately along and 75 statute miles north and south of a line from 40 miles northwest of Brainerd MN to 15 miles south southeast of Ironwood MI. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 553... AVIATION...A few severe thunderstorms with hail surface and aloft to 3 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 29030. ...Hart Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0255 PM CDT Thu Jul 27 2023 Valid 272000Z - 281200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF EASTERN MINNESOTA...WISCONSIN NORTHWOODS...WESTERN UPPER MICHIGAN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS WITHIN THE SOUTHERN NEW ENGLAND INTO THE MID-ATLANTIC... ...SUMMARY... Severe gusts and hail (some potentially significant) are possible the remainder of this afternoon and evening in parts of Minnesota and Wisconsin. Damaging to severe gusts also may occur today with thunderstorms in parts of the Mid-Atlantic/New England regions, and the central High Plains and Rockies. ...20Z Update... A few minor changes to wind probabilities from the Ohio Valley into the Northeast as well as modifications to the general thunder area based on the latest observational trends. The prior forecast reasoning otherwise remains valid. ..Wendt.. 07/27/2023 .PREV DISCUSSION... /ISSUED 1112 AM CDT Thu Jul 27 2023/ ...Northeast... A well-defined shortwave trough is moving across central NY today. Forcing for ascent ahead of this trough will aid in the development of scattered thunderstorms by mid-afternoon from parts of PA and southeast NY into southern and eastern New England. Rich low-level moisture and pockets of strong daytime heating will yield MLCAPE values around 2000 J/kg. Rather strong wind fields will promote relatively fast-moving storms capable of wind damage. Parts of southern New England may also have sufficient low-level vertical shear to pose a risk of a tornado or two. Please refer to MCDs #1736 and #1737 for further details. ...Western Great Lakes/Upper Midwest... Fast zonal flow is present today across the northern Plains, with 50-70 knot westerly winds above 6km noted on forecast soundings. A surface boundary is sagging southward across MN, and should provide the focus for rapid thunderstorm development later this afternoon. A very unstable air mass will develop from central MN into northern WI, along with sufficient deep-layer shear for supercells capable of very large hail. Storms are expected to persist well into the evening as they spread eastward into parts of Upper MI and much of northern/central WI. The risk of rather widespread damaging winds will increase across this area. Given the favorable environment and consistent 12z model signals, have upgraded portions of this area to ENH. ...Rockies and High Plains... Similar to yesterday, scattered high-based showers and thunderstorms are expected to develop over the high terrain of CO northward into much of WY and MT. Fast westerly flow and steep low-level lapse rates will promote a risk of damaging wind gusts in some of these storms. As activity spreads eastward into the Plains, a few more robust updrafts may also produce large hail. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0220 PM CDT Thu Jul 27 2023 Valid 281200Z - 291200Z No major changes will be made to the current outlook. Elevated fire-weather conditions are possible across the northern Great Basin and lee of the cascades with dry and breezy winds. A few thunderstorms are also possible overnight into D3/Saturday. The highest confidence areas for storms will be across parts of eastern OR and WA where weak elevated buoyancy is forecast. Little to no wetting rainfall is expected, but storm coverage should remain low. See the prior discussion for additional information. ..Lyons.. 07/27/2023 .PREV DISCUSSION... /ISSUED 0200 AM CDT Thu Jul 27 2023/ ...Synopsis... A mid-level trough will amplify along the West Coast as upper ridging intensifies over the Interior West tomorrow/Friday. Similar to Day 1, dry downslope flow should continue along the lee of the higher terrain. 15+ mph sustained west-southwesterly surface winds should overlap with 15 percent RH by afternoon peak heating, warranting the introduction of Elevated highlights. Thunderstorms will also be possible ahead of the trough and north of the upper ridge across the northern Rockies. Similar to previous days, any lightning strikes that can occur in dry fuel beds may encourage fire starts, potentially exacerbated by erratic, gusty winds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 1241 PM CDT Thu Jul 27 2023 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IOWA INTO THE SOUTHERN GREAT LAKES... CORRECTED FOR SUMMARY ...SUMMARY... Widely scattered severe thunderstorms are possible on Friday and Friday night across a large portion of the Midwest. ...Synopsis... Moderate to strong mid-level winds will remain along the northern periphery of an upper-level ridge. This flow will be confined to the northern Plains into the upper Midwest, though some amplification of the ridge could push moderate mid-level flow into the lower Great Lakes as well. A surface boundary will extend from the northern Plains into parts of the upper Midwest. A surface low is forecast to deepen slightly in the mid-Missouri Valley. Convective outflow and potential MCVs will also be present, but the location of these features is a bit uncertain. ...Lower Great Lakes/Midwest... Convection within the upper Mississippi Valley on Thursday night into Friday morning will play a role in how convection evolves during Friday afternoon. Guidance is variable in the placement of the outflow/MCV from this activity. However, the general consensus places these features within southern Wisconsin into parts of the upper Ohio Valley. South of the outflow, strong buoyancy is expected to develop. Shear will be strongest along and north of the boundary and decrease with southward extent. Forcing for ascent will generally be nebulous outside of areas impacted by the MCV. The expectation is for a cluster or two of storms to develop and progress eastward/southeastward into the MLCAPE reservoir. Large hail would be possible with initial activity before upscale growth occurs and severe/damaging winds would become the primary threat. A corridor of greater severe wind potential could develop given the clustering and strong instability, but uncertainty in the placement of boundaries and the eventual convective evolution precludes an increase in probabilities. Convection developing within parts of Montana may be ongoing at the beginning of the period. This activity and associated MCV could potentially intensify if it is able to progress into the greater buoyancy within South Dakota/Nebraska. This activity would also pose a risk of primarily strong/damaging winds and isolated large hail possible as well. Confidence in this scenario is also too low for any increase in wind probabilities. ...Southwest Montana... Stronger mid-level winds will persist across the northern Rockies. Convection is likely to develop within the higher terrain. Steep low and mid-level lapse rates will allow for strong wind gusts to reach the surface. Marginally severe hail will also be possible. ...Northern Maine... Strong westerly mid to high-level flow accompanying the aforementioned speed max will overspread the region during the day. It appears at least marginal destabilization will occur with surface dewpoints well into the 60s. A band of storms along a frontal zone will probably push eastward into Maine during the afternoon/early evening. Isolated severe gusts are the primary hazard. ..Wendt.. 07/27/2023 Read more

MD 1732 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF CENTRAL WYOMING
Mesoscale Discussion 1732 NWS Storm Prediction Center Norman OK 0446 PM CDT Wed Jul 26 2023 Areas affected...portions of central Wyoming Concerning...Severe potential...Watch unlikely Valid 262146Z - 262315Z Probability of Watch Issuance...5 percent SUMMARY...A few more severe gusts may occur with ongoing storms across central WY. The severe threat should remain isolated and a Severe Thunderstorm Watch issuance is unlikely. DISCUSSION...A semi-organized cluster of pulse-cellular storms have produced measured severe gusts over the past few hours and is poised to progress eastward atop a heated, well-mixed boundary layer. MRMS mosaic radar imagery shows a slight increase in the intensity of storm cores, and 21Z mesoanalysis shows boundary-layer lapse rates exceeding 9.8 C/km in some locales. As such, severe gusts should remain a concern through the rest of the afternoon until boundary-layer stabilization sets in during the evening. Severe gusts should by isolated, so a WW issuance is not expected. ..Squitieri/Grams.. 07/26/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...UNR...CYS...RIW... LAT...LON 43580850 44010820 44230733 44340545 44180486 43500473 42780532 42420630 42310691 42340756 42330789 42520804 43580850 Read more

MD 1731 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF CENTRAL NORTH DAKOTA...SOUTH DAKOTA...AND NEBRASKA
Mesoscale Discussion 1731 NWS Storm Prediction Center Norman OK 0431 PM CDT Wed Jul 26 2023 Areas affected...portions of central North Dakota...South Dakota...and Nebraska Concerning...Severe potential...Watch unlikely Valid 262131Z - 262300Z Probability of Watch Issuance...20 percent SUMMARY...A risk for isolated severe gusts/hail exists this afternoon with the stronger storms that can sustain themselves. A WW issuance is not currently anticipated. DISCUSSION...Strong boundary-layer heating and broad surface lee troughing is supporting the development of isolated, high-based supercells across the northern Plains. 100 F surface temperatures amid low 50s-60s F dewpoints (40-50 F T/Td spreads) preceding the supercells are contributing to 9+ C/km boundary-layer lapse rates. While 7-8 C/km mid-level lapse rates and 40+ kts of effective bulk shear (driven by elongated hodographs) suggest that mid-level updraft rotation and hail potential exists, the deep and hot boundary layer may promote sufficient melting of hail as well as evaporation of rain to support a severe gust threat through the remainder of the afternoon. Given the isolated nature of the storms and their severe threat, a Severe Thunderstorm Watch issuance is not currently expected. ..Squitieri/Grams.. 07/26/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FSD...ABR...GID...BIS...LBF...UNR... LAT...LON 40540075 44300160 46410163 47560055 47700001 47279933 46529886 45329848 43919845 42499860 41539886 40889919 40429954 40540075 Read more

WW 0551 Status Updates
STATUS REPORT ON WW 551 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 WNW MFD TO 35 ESE MTC TO 15 SW OSC. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1728 ..WEINMAN..07/26/23 ATTN...WFO...DTX...CLE... STATUS REPORT FOR WS 551 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MIC063-151-262240- MI . MICHIGAN COUNTIES INCLUDED ARE HURON SANILAC OHC007-035-043-055-077-085-093-103-262240- OH . OHIO COUNTIES INCLUDED ARE ASHTABULA CUYAHOGA ERIE GEAUGA HURON LAKE LORAIN MEDINA PAC039-049-262240- PA . PENNSYLVANIA COUNTIES INCLUDED ARE Read more

WW 551 SEVERE TSTM MI OH LE LH 261805Z - 262300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 551 NWS Storm Prediction Center Norman OK 205 PM EDT Wed Jul 26 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southeast Lower Michigan Northern Ohio Lake Erie Lake Huron * Effective this Wednesday afternoon and evening from 205 PM until 700 PM EDT. * Primary threats include... Scattered damaging winds likely with isolated significant gusts to 75 mph possible Isolated large hail events to 1.5 inches in diameter possible A tornado or two possible SUMMARY...Several fast-moving clusters of thunderstorms will track across the watch area this afternoon. The strongest cells will pose a risk of damaging wind gusts and some hail. The severe thunderstorm watch area is approximately along and 70 statute miles east and west of a line from 20 miles north of Bad Axe MI to 40 miles west southwest of Cleveland OH. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU1). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 550... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27040. ...Hart Read more

MD 1729 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR NORTHEASTERN COLORADO...FAR SOUTHEASTERN WYOMING...FAR SOUTHWESTERN NEBRASKA...NORTHWESTERN KANSAS
Mesoscale Discussion 1729 NWS Storm Prediction Center Norman OK 0337 PM CDT Wed Jul 26 2023 Areas affected...northeastern Colorado...far southeastern Wyoming...far southwestern Nebraska...northwestern Kansas Concerning...Severe potential...Watch possible Valid 262037Z - 262230Z Probability of Watch Issuance...60 percent SUMMARY...Severe potential increasing into the afternoon/evening. DISCUSSION...Thunderstorm activity has been ongoing across the Front Range and areas just west and south of the Denver Metro. Dew points within this region are generally in the mid 40s to 50s. High-based convection is expected to gradually shift into the plains through the evening, where a more moist and unstable air mass is available. This may lead to a more organized severe threat later for northeastern Colorado/far southeastern Wyoming persisting into southwestern Nebraska and northwestern Kansas later this evening. The main threats would be damaging winds, given "inverted V" thermodynamic profiles. Hodographs are generally straight with deep layer shear around 40 kts which may support a few isolated instances of large hail early on. Trends will be monitored for potential watch issuance over the next few hours. ..Thornton/Hart.. 07/26/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...GLD...PUB...BOU...CYS... LAT...LON 39530518 40060541 40500555 40700557 40990554 41170528 41290472 41330402 41340345 41310280 41250216 41110177 40910133 40600097 40120067 39790057 39460060 39420062 38960088 38700117 38670145 38620178 38600312 38540348 38520383 38530407 38630430 38800463 38960485 39530518 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0302 PM CDT Wed Jul 26 2023 Valid 262000Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE SOUTHERN GREAT LAKES REGION... ...SUMMARY... Severe thunderstorm gusts remain possible this afternoon and evening for parts of the southern Great Lakes, along with occasional large hail. Severe gusts also are possible over parts of the central High Plains this afternoon. ...20Z Update... The primary changes to the ongoing forecast were to reduce wind probabilities in the wake of convection, trim severe probabilities behind the shortwave trough in the Upper Midwest along with minor changes to the general thunderstorm area. The remainder of forecast remains on track with additional thunderstorm development possible in the southern Great Lakes region as the low-level jet intensifies later today/tonight. ..Wendt.. 07/26/2023 .PREV DISCUSSION... /ISSUED 1109 AM CDT Wed Jul 26 2023/ ...Lower MI and Vicinity... Multiple strong/severe MCSs are ongoing this morning over western Lower MI, Lake MI, and southern WI. Two lead bowing clusters of convection over western Lower MI will likely continue to track quickly eastward today into a progressively more unstable air mass. Dewpoints in the mid/upper 60s and relatively strong heating will yield afternoon MLCAPE values over 2000 J/kg. Mid-level lapse rates are not particularly steep, but rather strong winds aloft and mesoscale organization of these clusters will help to pose a risk of damaging winds across much of central/eastern Lower MI through the afternoon. The potential also exists for a few supercells to form ahead of the main bowing structures, posing a risk of hail and a few tornadoes as well. Behind the lead convection, another bowing MCS is moving across southwest WI. These storms are closer to the mid-level vorticity center and even stronger winds aloft. It is unclear how much destabilization can occur in the wake of the lead storms, but it seems plausible that this cluster will also pose a severe risk through much of the afternoon and evening, traversing a similar track as the southern lead bowing structure. ...UT to CO/KS/NE... A corridor of sufficient mid-level moisture is expected to result in scattered high-based showers and thunderstorms from parts of UT into northern CO and southern WY today. As the storms over the CO mountains spread eastward into the plains, they will encounter an increasingly moist and unstable air mass. A few of these storms may become severe by late afternoon/evening with damaging winds being the main concern. ...Southern AZ... Several 12z HREF members show a cluster of thunderstorms developing over the higher terrain of southern AZ and spreading northwestward during the evening. If this scenario unfolds, strong wind gusts could affect the region. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0210 PM CDT Wed Jul 26 2023 Valid 271200Z - 281200Z The previous forecast remains valid with only minor adjustments for the latest guidance. A few hours of dry and breezy conditions are possible from the southern Cascades to the northern Great Basin. A few thunderstorms are also possible early in the morning and again in the afternoon. However, lightning coverage will be low. Please see the prior discussion for more information. ..Lyons.. 07/26/2023 .PREV DISCUSSION... /ISSUED 0107 AM CDT Wed Jul 26 2023/ ...Synopsis... Strong mid-level flow will traverse the periphery of a stationary upper ridge (centered over the Southern Rockies) and will overspread the northern Great Basin tomorrow/Thursday. By afternoon peak heating, downslope flow along the higher terrain will support 15-20 mph sustained westerly surface winds from the California/Nevada border into the Snake River Plain. Coinciding these breezy surface conditions will be 10-15 percent RH, warranting the introduction of Elevated highlights. Monsoonal moisture associated with the upper ridge will support another day of scattered thunderstorms over the Rockies. Any strikes that can occur in patchy dry fuel beds will support a localized wildfire-spread threat. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0550 Status Updates
STATUS REPORT ON WW 550 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..WEINMAN..07/26/23 ATTN...WFO...IWX...GRR... STATUS REPORT FOR WS 550 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS INC039-087-091-141-151-261940- IN . INDIANA COUNTIES INCLUDED ARE ELKHART LAGRANGE LA PORTE ST. JOSEPH STEUBEN MIC005-015-021-023-025-027-035-037-045-057-059-065-067-073-075- 077-081-085-105-107-117-121-123-127-133-139-149-159-261940- MI . MICHIGAN COUNTIES INCLUDED ARE ALLEGAN BARRY BERRIEN BRANCH CALHOUN CASS CLARE CLINTON EATON GRATIOT HILLSDALE INGHAM IONIA ISABELLA JACKSON KALAMAZOO KENT LAKE MASON MECOSTA MONTCALM MUSKEGON NEWAYGO OCEANA OSCEOLA OTTAWA ST. JOSEPH VAN BUREN Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1237 PM CDT Wed Jul 26 2023 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF NEW ENGLAND INTO THE MID-ATLANTIC... ...SUMMARY... Widely scattered severe thunderstorms are forecast across southern New England southward into portions of the Mid-Atlantic states on Thursday. Damaging gusts and a couple tornadoes will be the primary hazards. ...Synopsis... A shortwave trough currently in the upper Midwest will continue eastward into Thursday. This feature is forecast to reach New England by early afternoon. Strong mid-level flow will persist across the northern periphery of the upper-level ridge in the northern Plains into the upper Mississippi Valley. A surface low will move through the Northeast along with an associated warm front and a weak front/surface trough trailing into the Blue Ridge/Piedmont regions. Another surface boundary in the northern Plains into northern Minnesota/Wisconsin/Upper Peninsula Michigan will sag southward. ...Northeast/Mid-Atlantic... Some ongoing activity is expected during the morning within the Northeast, likely near the Canadian border. Some lingering cloud cover can be expected perhaps into the early afternoon. Cloud cover will generally decrease with southward extent into the Mid-Atlantic. Heating through broken cloud cover in New England should be sufficient to promote at least 1000-1500 J/kg MLCAPE given the moist airmass expected. Deep-layer shear with the shortwave trough will not be overly strong (30-40 kts), but should allow for some storm organization with a mix of discrete cells and multicells. Low-level wind fields will be moderately strong and promote a risk for damaging winds with the strongest updrafts. Near the warm front, low-level shear will also favor some potential for low-level rotation and a threat for a couple tornadoes. Should greater surface heating occur, greater risk for damaging winds could be realized. Farther south into the Mid-Atlantic, weaker shear will be present. Stronger surface heating will still promote buoyancy perhaps in excess of 2000 J/kg MLCAPE. Damaging wind gusts and isolated large hail would be the main threats with activity moving off of the Blue Ridge. ...Central High Plains into Upper Midwest... Deep-layer shear will be maximized near the surface boundary and weaken with southward extent across the broad region. Scattered storms appear most likely within the higher terrain of Wyoming into eastern Colorado. These storms would primarily pose a threat of strong/severe wind gusts. Strong heating within the Plains could allow for isolated strong/severe storms to develop. Forcing will be weak and capping will keep storm development uncertain. Guidance does show a weak surface low developing in Minnesota into northwest Wisconsin. Surface convergence may be great enough to allow a cluster of storms to develop. Shear in this region would be favorable for supercells initially. Large hail and strong/severe wind gusts would be possible. Weak low-level shear and deep-layer shear parallel to the boundary, however, suggests upscale growth would occur relatively quickly and limit the duration of the large hail threat. ..Wendt.. 07/26/2023 Read more

MD 1707 CONCERNING SEVERE THUNDERSTORM WATCH 546... FOR SOUTHERN NEW ENGLAND
Mesoscale Discussion 1707 NWS Storm Prediction Center Norman OK 0516 PM CDT Tue Jul 25 2023 Areas affected...Southern New England Concerning...Severe Thunderstorm Watch 546... Valid 252216Z - 260015Z The severe weather threat for Severe Thunderstorm Watch 546 continues. SUMMARY...A few strong storms will spread across southern New England this evening. Gusty winds remain the primary threat. DISCUSSION...Large-scale forcing ahead of progressive short-wave trough is advancing across the northern Middle Atlantic into southern New England early this evening. A small pocket of modest instability has yet to be overturned over eastern CT/RI into southeast MA. Over the next few hours, strong convection is expected to propagate east-southeast across southern New England with an attendant threat for gusty winds. Even so, convection should gradually weaken as it progresses toward coastal MA due to weaker buoyancy. ..Darrow.. 07/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BOX...OKX... LAT...LON 41987258 42007127 41267136 41157283 41987258 Read more