Severe Storms

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

MD 1706 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF EASTERN NORTH DAKOTA INTO FAR WESTERN MINNESOTA
Mesoscale Discussion 1706 NWS Storm Prediction Center Norman OK 0457 PM CDT Tue Jul 25 2023 Areas affected...portions of eastern North Dakota into far western Minnesota Concerning...Severe potential...Watch possible Valid 252157Z - 252330Z Probability of Watch Issuance...60 percent SUMMARY...The severe threat is increasing across portions of North Dakota into northwestern Minnesota. Severe hail and wind are the main threats. Convective coverage trends are being monitored for the need of a Severe Thunderstorm Watch. DISCUSSION...MRMS mosaic radar imagery depicts an increase in convective intensity across ND as a subtle mid-level trough overspreads the region, with at least one supercell taking shape in Cavalier County, ND. Though appreciable convective inhibition remains in place, strong surface heating of a moist low-level airmass (characterized by near 70 F surface dewpoints) supports 3000-5000 J/kg MLCAPE (per 21Z mesoanalysis). At the moment, it is unclear if the upper support across the northern Plains will compensate for the substantial CINH to support a relatively widespread severe threat. On the other hand, given the instability, any storm that can mature and become sustained should support a severe wind and hail threat. As such, convective trends will continue to be monitored for the need of a Severe Thunderstorm Watch. ..Squitieri/Thompson.. 07/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...BIS... LAT...LON 45989853 48399840 48999806 49119739 48909647 48519616 47829605 47139604 46549596 46269604 46129634 45949714 45989853 Read more

WW 0546 Status Updates
140- STATUS REPORT ON WW 546 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 W BWI TO 10 ENE TTN TO 30 NNE EWR TO 25 N POU. ..KERR..07/25/23 ATTN...WFO...OKX...BOX...ALY...LWX...PHI...CTP... STATUS REPORT FOR WS 546 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS CTC001-003-005-007-009-011-013-015-252140- CT . CONNECTICUT COUNTIES INCLUDED ARE FAIRFIELD HARTFORD LITCHFIELD MIDDLESEX NEW HAVEN NEW LONDON TOLLAND WINDHAM DEC001-003-005-252140- DE . DELAWARE COUNTIES INCLUDED ARE KENT NEW CASTLE SUSSEX DCC001-252140- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA Read more

WW 546 SEVERE TSTM CT DC DE MD NJ NY PA VA CW 251610Z - 260000Z
0- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 546 NWS Storm Prediction Center Norman OK 1210 PM EDT Tue Jul 25 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Connecticut District Of Columbia Delaware Eastern Maryland New Jersey Southeast New York Eastern Pennsylvania Northern Virginia Coastal Waters * Effective this Tuesday afternoon and evening from 1210 PM until 800 PM EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Thunderstorms will increase from northern Virginia into eastern Pennsylvania this afternoon, then track eastward across the watch area through the day. Damaging winds are possible in the strongest storms. The severe thunderstorm watch area is approximately along and 70 statute miles east and west of a line from 10 miles west northwest of Windsor Locks CT to 45 miles east southeast of Washington DC. 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. && AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27030. ...Hart Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Tue Jul 25 2023 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE NORTHEAST...AND OVER PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Scattered severe wind/hail-producing thunderstorms are possible across parts of the Northern Plains and the Northeast into this evening. Isolated severe gusts are also possible over portions of the Interior West. ...20z Update... No changes have been made to the outlook with the 20z Update. Scattered severe thunderstorms will continue to shift east/northeast across WW 546 the next few hours before moving offshore the Mid-Atlantic/Northeast coast. Additional severe thunderstorms are expected to develop over the northern Plains in the next few hours. These storms will shift east/southeast through the evening into early tonight, producing hail and damaging gusts. ..Leitman.. 07/25/2023 .PREV DISCUSSION... /ISSUED 1129 AM CDT Tue Jul 25 2023/ ...Mid Atlantic into southern New England... A remnant MCV is currently over eastern PA. This feature is embedded within a larger-scale shortwave trough and associated 40 knot mid-level jet moving into the northeast states. Forcing ahead of these features is leading to scattered thunderstorm development. Strong heating across the region, coupled with dewpoints in the 70s will lead to moderate CAPE values over 2000 J/kg. Sufficient winds aloft and steep low-level lapse rates will promote locally damaging wind gusts in the stronger cells through early evening. Storms will eventually build southward into eastern VA/MD as well. ...Northern Plains... Water vapor imagery shows a fast-moving shortwave trough over MT/WY. This feature will emerge into the Plains this afternoon, with large scale ascent overspreading the Dakotas. As this ascent reaches the western edge of deeper/richer moisture over central ND/SD, thunderstorms are expected to rapidly develop. Initial storms will likely be supercells with a risk of large hail and damaging winds. Storms should congeal upscale through the evening as they track east-southeastward into southwest MN/western IA with a continued risk of damaging winds. Other more isolated severe storms may develop southward into parts of NE and northeast CO, with a localized risk of damaging winds and hail. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0247 PM CDT Tue Jul 25 2023 Valid 261200Z - 271200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHWEST NV...PORTIONS OF FAR SOUTHERN OR...AND NORTHEAST CA... ...Eastern OR/WA and the ID Panhandle... A shortwave mid-level trough is forecast to move over portions of the Northern Great Basin into the Northwest late D2/Wed into early D3/Thur morning. Subtle forcing for ascent, and mid-level moisture will aid in isolated, mostly nocturnal, thunderstorm chances. Hi-res guidance shows some potential for lightning to interact with drier fuel beds across far eastern WA/OR into portions of the ID Panhandle. Should this occur, a few lightning ignitions are possible as fuels have dried over the preceding days. However, overall confidence in storm coverage is too low for IsoDryT highlights. Otherwise critical fire-weather conditions are possible over the northern great Basin. The prior forecast remains valid with no changes. See previous discussion. ..Lyons.. 07/25/2023 .PREV DISCUSSION... /ISSUED 0142 AM CDT Tue Jul 25 2023/ ...Synopsis... A series of mid-level troughs will crest the southern Rockies stationary ridge and traverse the Pacific Northwest and northern Rockies tomorrow/Wednesday. Strong forcing accompanying the passing troughs will support widespread 15+ mph sustained westerly surface winds amid 15-20 percent RH by afternoon peak heating in and to the south of the Harney Basin and also northern Montana, necessitating Elevated highlights. Surface winds may be stronger along the California/Nevada/Oregon border, prompting the addition of Critical highlights this outlook. Similar to previous days, monsoonal moisture associated with the stationary upper ridge may promote a few high-based thunderstorms with erratic wind gusts by afternoon, with fire starts possible wherever lightning can strike in dry fuel beds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 1701 CONCERNING SEVERE THUNDERSTORM WATCH 545... FOR PORTIONS OF KY...IN...AND OH
Mesoscale Discussion 1701 NWS Storm Prediction Center Norman OK 0512 PM CDT Mon Jul 24 2023 Areas affected...Portions of KY...IN...and OH Concerning...Severe Thunderstorm Watch 545... Valid 242212Z - 242345Z The severe weather threat for Severe Thunderstorm Watch 545 continues. SUMMARY...Ongoing thunderstorms should continue to pose a threat for severe hail and damaging winds for a couple more hours this evening. DISCUSSION...Convection that strengthened earlier this afternoon across the OH Valley along and ahead of a weak front has produced occasional severe hail and damaging winds over the past couple of hours. The thermodynamic environment across this region remains favorable for robust thunderstorms in the short term, with latest mesoanalysis estimates showing around 2000-3500 J/kg MLCAPE present. Recent VWPs from area radars suggest low to mid-level flow remains fairly modest below about 6 km AGL, with some strengthening of northwesterly winds around 7-9 km AGL. A mix of multicells and marginal supercells should continue to pose a threat for mainly severe hail and damaging winds, respectively. This convection is forecast to slowly spread east-southeastward across parts of KY, southern/eastern IN, and southern/western OH over the next couple of hours. A less unstable airmass with eastward extent across the OH Valley and eventual nocturnal cooling should limit the overall severe threat farther east later this evening. ..Gleason.. 07/24/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PBZ...RLX...CLE...JKL...ILN...LMK...IND...PAH... LAT...LON 38678706 40068577 40528325 40278228 39778216 38768269 38098396 37728517 36668570 36668740 37698688 38678706 Read more

MD 1700 CONCERNING SEVERE THUNDERSTORM WATCH 544... FOR PARTS OF NORTHEAST PENNSYLVANIA INTO NEW YORK
Mesoscale Discussion 1700 NWS Storm Prediction Center Norman OK 0453 PM CDT Mon Jul 24 2023 Areas affected...parts of northeast Pennsylvania into New York Concerning...Severe Thunderstorm Watch 544... Valid 242153Z - 250000Z The severe weather threat for Severe Thunderstorm Watch 544 continues. SUMMARY...The severe threat continues across Severe Thunderstorm Watch 544. Strong wind gusts remain the primary concern this evening. DISCUSSION...Multiple rounds of thunderstorms have moved across the portions of the Hudson Valley this afternoon with a history of damaging gusts. The airmass across much of eastern NY into New England has become overturned by earlier storms, though ongoing storms across central NY are approaching from the west. Given limited airmass modification ahead of these storms (i.e. surface temperatures warming into the mid 70s F), a couple of additional strong wind gusts may still occur before storms wane in intensity this evening. An instance or two of large hail also cannot be ruled out. Storms should gradually decrease in intensity this evening as nocturnal cooling and further airmass overturning occurs with ongoing storms. ..Squitieri.. 07/24/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BTV...ALY...BGM...BUF...CTP... LAT...LON 41707685 44037537 44877431 44687379 44327331 43807306 43217324 42647373 42027431 41687478 41467516 41267618 41707685 Read more

MD 1699 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF NORTHEAST NEVADA INTO NORTHWESTERN UTAH...SOUTHEAST IDAHO...WESTERN WYOMING
Mesoscale Discussion 1699 NWS Storm Prediction Center Norman OK 0433 PM CDT Mon Jul 24 2023 Areas affected...portions of northeast Nevada into northwestern Utah...southeast Idaho...western Wyoming Concerning...Severe potential...Watch unlikely Valid 242133Z - 242300Z Probability of Watch Issuance...20 percent SUMMARY...A couple of severe gusts may accompany the stronger storms this evening. A WW issuance is not expected. DISCUSSION...Scattered thunderstorms are developing along the northwestern periphery of a monsoonal moisture plume as an embedded 500 mb impulse grazes the Great Basin. These storms are developing atop a heated, mixed boundary layer, characterized by surface temperatures exceeding 90 F in several locales. The strong surface heating has resulted in boundary-layer lapse rates reaching 10 C/km in some locales. As such, efficient evaporative cooling with the more intense storm cores may support a couple of severe gusts. Nonetheless, the severe threat should remain isolated and a WW issuance is not expected. ..Squitieri.. 07/24/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RIW...TFX...SLC...PIH...BOI...LKN... LAT...LON 39861606 42611407 44001218 44451148 44521117 43620941 43080924 42010920 40881014 40031094 39621187 39571332 39651460 39861606 Read more

WW 0545 Status Updates
STATUS REPORT ON WW 545 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..GLEASON..07/24/23 ATTN...WFO...IND...LMK...ILN... STATUS REPORT FOR WS 545 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS INC005-011-013-019-025-027-029-031-035-037-041-043-047-055-057- 059-061-063-065-071-077-079-081-083-093-095-097-101-105-109-115- 117-119-123-135-137-139-143-145-155-159-161-175-177-242240- IN . INDIANA COUNTIES INCLUDED ARE BARTHOLOMEW BOONE BROWN CLARK CRAWFORD DAVIESS DEARBORN DECATUR DELAWARE DUBOIS FAYETTE FLOYD FRANKLIN GREENE HAMILTON HANCOCK HARRISON HENDRICKS HENRY JACKSON JEFFERSON JENNINGS JOHNSON KNOX LAWRENCE MADISON MARION MARTIN MONROE MORGAN OHIO ORANGE OWEN PERRY RANDOLPH RIPLEY RUSH SCOTT SHELBY SWITZERLAND TIPTON UNION WASHINGTON WAYNE KYC003-005-009-015-017-023-027-029-031-037-041-061-073-077-081- 085-091-093-097-099-103-111-117-123-135-141-161-163-179-181-183- Read more

WW 545 SEVERE TSTM IN KY OH 241940Z - 250200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 545 NWS Storm Prediction Center Norman OK 340 PM EDT Mon Jul 24 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southern Indiana Northern Kentucky Southwest Ohio * Effective this Monday afternoon and evening from 340 PM until 1000 PM EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Thunderstorms will increase in coverage this afternoon in a moist and very unstable air mass. The strongest cells will pose a risk of damaging wind gusts and hail through the afternoon and early evening. The severe thunderstorm watch area is approximately along and 75 statute miles north and south of a line from 45 miles south southwest of Bloomington IN to 30 miles east of Columbus OH. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). 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 544... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 28030. ...Hart Read more

WW 0544 Status Updates
STATUS REPORT ON WW 544 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..KERR..07/24/23 ATTN...WFO...ALY...BGM...BUF...BTV... STATUS REPORT FOR WS 544 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS CTC005-242140- CT . CONNECTICUT COUNTIES INCLUDED ARE LITCHFIELD MAC003-242140- MA . MASSACHUSETTS COUNTIES INCLUDED ARE BERKSHIRE NYC001-007-011-015-017-019-021-023-025-027-031-033-035-039-041- 043-045-049-053-057-065-067-075-077-083-089-091-093-095-097-099- 101-105-107-109-111-113-115-123-242140- NY . NEW YORK COUNTIES INCLUDED ARE ALBANY BROOME CAYUGA CHEMUNG CHENANGO CLINTON COLUMBIA CORTLAND DELAWARE Read more

WW 544 SEVERE TSTM CT MA NY PA VT 241705Z - 250000Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 544 NWS Storm Prediction Center Norman OK 105 PM EDT Mon Jul 24 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western Connecticut Western Massachusetts Central and Eastern New York Northeast Pennsylvania Vermont * Effective this Monday afternoon and evening from 105 PM until 800 PM EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Thunderstorms will continue to increase in coverage and intensity through the afternoon as daytime heating destabilizes the atmosphere. The strongest storms this afternoon will pose a risk of locally damaging wind gusts. The severe thunderstorm watch area is approximately along and 90 statute miles east and west of a line from 35 miles west of Monticello NY to 35 miles north northwest of Burlington VT. 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. && AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 24025. ...Hart Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Mon Jul 24 2023 Valid 242000Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE NORTHEAST AND THE OHIO VALLEY... ...SUMMARY... Severe thunderstorms associated with strong wind gusts will be possible into these evening across parts of the Northeast states and the Ohio Valley. ...20z Update... A small southward expansion to the Marginal risk (level 1 of 5) over TN has been made to account for a developing cluster over southeast MO and potential for that cluster to continue south/southeast through early evening. Reference MCD 1697 for short term details on this severe risk. The Slight risk (level 2 of 5) as also been expanded westward across parts of southern IN, central/western KY and northwest TN to account for ongoing observational trends. Reference MCD 1695 and WW 545 for more information. Otherwise, the Marginal risk has been trimmed across much of MO into parts of IL where morning convection has resulted in stronger inhibition and lowered severe potential. Reference MCDs 1696 and WW 544 for more information regarding short term severe potential across the Northeast. ..Leitman.. 07/24/2023 .PREV DISCUSSION... /ISSUED 1122 AM CDT Mon Jul 24 2023/ ...Northeast... Morning water vapor loop shows a series of shortwave troughs over western/central NY and Lake Ontario. Lift ahead of these systems will promote the development of scattered thunderstorms across parts of NY/PA, spreading eastward into VT. Forecast soundings show relatively steep low-level lapse rates and sufficient westerly flow above 3km to help organize the stronger cells and pose a risk of damaging wind gusts. Please refer to MCD #1694 for further details. ...OH Valley... A moist low-level air mass is present today from southern OH westward into IN/IL/KY with dewpoints in the upper 60s and 70s. A shortwave trough over WI will approach the area later this afternoon, with isolated to scattered thunderstorm development likely. Ample CAPE and sufficient northwest flow aloft will result in a few strong/severe storms capable of damaging wind gusts. A consensus of 12z guidance shows a higher concentration of storms over parts of southwest OH and adjacent parts of KY/IN. Therefore a small SLGT has been added for that region. ...NV/UT/ID/MT/WY... A large upper ridge is in place today over much of the Great Basin, with a band of stronger flow extending from NV into UT/ID and WY/MT. A shortwave trough embedded in this flow over NV will track northeastward and aid in the development scattered high-based showers and thunderstorms later today. This activity may pose a risk of gusty/damaging winds through the evening. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0208 PM CDT Mon Jul 24 2023 Valid 251200Z - 261200Z ...Columbia Basin... Recent model guidance has trended drier and windier with surface conditions across eastern WA and OR in the wake of the cold front moving through on D1/Mon. Model soundings show afternoon RH values below 20-25% with winds gusts to 15-20 mph through the Cascade gaps and the western portions of the Columbia Basin. With the increased confidence in dry and breezy conditions over dry fuels, a few hours of elevated to near-critical fire-weather conditions now appear likely D2/Tues afternoon. Otherwise, the previous forecast remains valid with minimal changes for the latest forecast guidance. See the prior discussion for more information. ..Lyons.. 07/24/2023 .PREV DISCUSSION... /ISSUED 1247 AM CDT Mon Jul 24 2023/ ...Synopsis... Relatively strong mid-level flow will traverse the periphery of an upper ridge, poised to remain in place across the Interior West tomorrow/Tuesday. The stronger flow aloft may encourage dry downslope flow along the lee of the northern Sierra and parts of the higher terrain within the northern Rockies. Latest guidance consensus suggests that RH may drop below 20 percent in several locales as sustained westerly surface winds peak over 15 mph for at least a few hours, necessitating Elevated highlights. Meanwhile, monsoonal moisture will remain trapped near the stationary upper ridge, supporting at least scattered thunderstorm development with afternoon heating. Any lightning strikes that can occur within one of the more isolated dry fuel beds may promote localized wildfire-spread potential. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sun Jul 23 22:01:02 UTC 2023.

MD 1686 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF MO INTO WEST-CENTRAL IL
Mesoscale Discussion 1686 NWS Storm Prediction Center Norman OK 0458 PM CDT Sun Jul 23 2023 Areas affected...Portions of MO into west-central IL Concerning...Severe potential...Watch unlikely Valid 232158Z - 240030Z Probability of Watch Issuance...5 percent SUMMARY...An isolated risk for severe hail and damaging winds may continue into the early evening. Watch issuance is not expected at this time. DISCUSSION...Scattered thunderstorms have developed late this afternoon along a weak surface trough across parts of northern/eastern MO as a weak mid-level disturbance cresting the upper ridge continues southeastward across the upper/mid MS Valley. The airmass downstream of this activity into central MO and west-central IL is moderately unstable, with MLCAPE generally 2000-2500 J/kg. But, deep-layer shear remains marginal, around 20-25 kt, given fairly modest mid/upper-level northwesterly flow. Still, occasional updraft organization has been noted with the strongest cores, with a recent 1 inch severe hail report. Isolated severe hail and damaging winds may remain a threat with this convection as it spreads slowly southward over the next couple of hours. Given the weak shear, watch issuance is not expected at this time. ..Gleason/Thompson.. 07/23/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LSX...SGF...EAX... LAT...LON 39779333 39559212 39599083 39078997 38249005 37969152 38149303 38699365 39379363 39789333 39779333 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sun Jul 23 2023 Valid 232000Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF NORTHERN SC AND WESTERN NC... ...SUMMARY... Strong to severe storms will remain possible late this afternoon and evening, at least on an isolated basis, across the Southeast States as well as the northern/central Plains and Ozarks. A few strong wind gusts could also occur in Arizona. ...20Z Update... The Marginal Risk has been expanded westward to include more of southwest SD and western NE, based on latest short-term guidance, destabilization trends, and increasing cumulus near the Black Hills. The Marginal Risk has been trimmed in the wake of earlier convection across parts of FL and GA. Otherwise, no major changes have been made. See the previous discussion below for more details. ..Dean.. 07/23/2023 .PREV DISCUSSION... /ISSUED 1127 AM CDT Sun Jul 23 2023/ ...Carolinas... Mostly sunny skies are present today from much of GA across the Carolinas. Ample low-level moisture will yield afternoon MLCAPE values of 1500-2000 J/kg, along with rather strong mid/upper level winds. 12z CAM solutions show a more robust signal for higher thunderstorm coverage across parts of northern SC into central NC. Therefore have opted to add a SLGT risk for parts of SC/NC for this afternoon and evening. ...FL... A large but relatively disorganized MCS is moving across the northeast Gulf of Mexico into northern FL. Strong heating ahead of this system will lead to occasional intense storms along the leading edge of the combined outflow. Forecast soundings show rather limited deep-layer shear and lapse rates, suggesting that activity will not be very organized or long-lived. However, locally gusty/damaging winds could occur. ...Central/Northern Plains... A large area of moderate/strong instability and fast northwest flow aloft lies across much of the northern and central Plains today. Forecast soundings across the region from the eastern Dakotas into KS/MO show sufficient CAPE/shear for a conditional risk of supercells capable of large hail and damaging wind gusts. However, forcing is weak and confidence in where afternoon convective initiation will occur is low. Therefore will maintain a broad MRGL risk. The strongest signal in 12z models appears to extend from south-central NE across central/eastern KS into west-central MO. This and other corridors will be monitored through the afternoon for a potential upgrade. ...AZ... Easterly flow aloft today will again pose some risk of convection moving off the higher terrain of eastern/northern AZ into higher population areas. Damaging winds would be the main concern. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0205 PM CDT Sun Jul 23 2023 Valid 241200Z - 251200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE NORTHERN GREAT BASIN INTO SOUTHEASTERN OR AND WESTERN ID... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE COLUMBIA BASIN IN EASTERN WA AND OR... ...Northern Great Basin... Widespread elevated and critical fire-weather conditions are expected D2/Monday ahead of the advancing trough. Updated fuels information across northwest NV lends higher confidence to critical conditions in lower elevations. The Critical area was expanded south and westward to better align with 25+ mph surface winds and low afternoon humidity. ...Columbia Basin and northern Rockies... As strong mid-level flow aligns with dry and warm surface conditions across portions of eastern WA and OR, westerly winds of 20-25 mph and higher gusts are expected over dry fuels. Several hours of widespread elevated and critical fire-weather conditions are expected to support the potential for rapid fire spread. A few showers and high-based thunderstorms are also possible later in the evening along and behind the cold front from far eastern WA into portions of western MT and the ID Panhandle. While not overly likely, any storms that do form may pose a risk for dry lightning strikes within modestly receptive fuels. please see the prior discussion for more information. ..Lyons.. 07/23/2023 .PREV DISCUSSION... /ISSUED 0123 AM CDT Sun Jul 23 2023/ ...Synopsis... A mid-level trough will remain in place across the Four Corners region as an upper trough traverses the Pacific Northwest tomorrow/Monday. Monsoonal moisture trapped beneath the mid-level ridge will encourage another day of scattered dry and wet thunderstorms across the Intermountain West. Given patchy, marginally receptive fuels, a couple of new fire starts are possible, resulting in localized wildfire-spread potential. The relatively greater potential for wildfire spread will exist across the Pacific Northwest as the passage of a mid-level trough will encourage critically dry and windy surface conditions. To the lee of the Cascades and northern Sierra, RH will dip below 15 percent by afternoon peak heating, with surface westerly winds sustaining over 20 mph in spots. The most likely region to see widespread 20+ mph wind speeds will be southeast Oregon into far northwest Nevada and far southwest Idaho, where Critical highlights have been introduced. ...Please see www.spc.noaa.gov/fire for graphic product... Read more