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No Mesoscale Discussions are in effect as of Sun May 21 21:45:07 UTC 2023.

WW 0230 Status Updates
STATUS REPORT ON WW 230 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..SMITH..05/21/23 ATTN...WFO...BOI...MSO...OTX...PDT... STATUS REPORT FOR WS 230 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IDC003-035-045-049-061-069-075-085-087-220000- ID . IDAHO COUNTIES INCLUDED ARE ADAMS CLEARWATER GEM IDAHO LEWIS NEZ PERCE PAYETTE VALLEY WASHINGTON ORC001-023-025-045-061-063-220000- OR . OREGON COUNTIES INCLUDED ARE BAKER GRANT HARNEY MALHEUR UNION WALLOWA WAC003-220000- WA . WASHINGTON COUNTIES INCLUDED ARE ASOTIN Read more

WW 230 SEVERE TSTM ID OR WA 212105Z - 220400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 230 NWS Storm Prediction Center Norman OK 205 PM PDT Sun May 21 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western and Central Idaho Eastern Oregon Southeast Washington * Effective this Sunday afternoon and evening from 205 PM until 900 PM PDT. * Primary threats include... Isolated damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Widely scattered thunderstorms will continue to develop through late afternoon, with sufficient instability and deep-layer winds to support potentially severe storms capable of hail and locally damaging winds. The severe thunderstorm watch area is approximately along and 65 statute miles east and west of a line from 45 miles southwest of Rome OR to 30 miles north northwest of Lowell ID. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). 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. ...Guyer Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sun May 21 2023 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN OREGON AND NORTHEAST WASHINGTON INTO WESTERN AND NORTHERN IDAHO... ...SUMMARY... Scattered severe thunderstorms are possible across portions of the interior Northwest, centered on 2 to 9 PM PDT. Large hail and isolated damaging gusts will be the primary hazards. ...20z Update... Other than trimming the 10 percent general thunderstorm line across parts of GA and the Carolinas, severe probabilities remain unchanged from the previous outlook. A few strong storms remain possible across parts of southeast GA into northern FL. For details on short term severe thunderstorm potential across that area, reference MCD 831. Severe thunderstorms are also expected to develop across parts of eastern OR into northeast WA and western/northern ID from late afternoon through the evening. Large hail and gusty winds are expected with this activity. For info on short term severe potential across the area, reference MCDs 832 and 833. ..Leitman.. 05/21/2023 .PREV DISCUSSION... /ISSUED 1118 AM CDT Sun May 21 2023/ ...Interior Northwest... Around the northwest periphery of a mid-level anticyclone over the Great Basin, a plume of 0.75 to 1 inch PW values will support rounds of convection persisting into early tonight. The threat for scattered afternoon/evening thunderstorms will shift eastward compared to prior days as a shortwave trough off the Pacific Northwest coast shifts inland into WA/OR. A weak 1013 mb surface low over eastern WA and attendant cold front arcing southwest into south-central OR will be the focus for more vigorous thunderstorm development later this afternoon. Low to mid 50s boundary-layer dew points will contribute to a corridor of MLCAPE from 1000-1500 J/kg in an arc ahead of the cold front. This moderate buoyancy along with strengthening speed shear above 700 mb will favor a few high-based supercells with mid-level rotation, especially over eastern OR to the southern ID Panhandle and in far northeast WA/northern ID Panhandle. Large hail should be the primary initial threat. Consolidating cells will yield more multicell clustering into the evening with an isolated mix of severe wind gusts and hail, before convection weakens over the northern Rockies after sunset. ...Southeast GA and the north FL Peninsula... A diffuse front along with colliding sea breezes will support scattered thunderstorms into early evening. 12Z JAX/TLH observed soundings sampled a belt of enhanced speed shear through the mid to upper-levels, which may be adequate to foster small hail production despite poor mid-level lapse rates. This may yield precip-loaded, locally strong downbursts in the more intense cells as MLCAPE peaks from 1500-2000 J/kg. ...Southern High Plains... Scattered, slow-moving thunderstorms are expected later this afternoon into the evening within a weakly buoyant air mass characterized by MLCAPE of 500-1000 J/kg. Modest mid-level lapse rates (especially compared to late May climo) away from the higher terrain and relatively weak vertical shear suggest that organized severe storms are unlikely. A very low probability of marginally severe hail and wind exists, but appears too minimal to warrant an areal delineation. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0206 PM CDT Sun May 21 2023 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... No changes. See previous discussion below. ..Bentley.. 05/21/2023 .PREV DISCUSSION... /ISSUED 1230 AM CDT Sun May 21 2023/ ...Synopsis... Moisture will gradually decrease across the Southwest into Monday as a weak upper level low meanders back south over the Baja Peninsula with a return to breezy west to southwest winds. Above normal rainfall within this region has left fuels less receptive to fire spread, precluding the need to include any areas. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1217 PM CDT Sun May 21 2023 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE TX PANHANDLE AND SOUTH PLAINS INTO FAR WESTERN OKLAHOMA... ...SUMMARY... Severe thunderstorms are possible across portions of the southern High Plains Monday afternoon and evening. Large hail and damaging gusts will be the primary hazards with these storms. Additional strong to isolated severe thunderstorms are possible across portions of Montana, and parts of southern Alabama/Georgia into Florida. ...Southern Plains... Convectively induced vorticity maxima are forecast to float across the southern Plains in the vicinity of the OK/TX Panhandles to western OK on Monday. This will lead to some enhancement of vertical shear in an otherwise weak flow regime. Boundary-layer moisture will remain modest by late-May standards, though some increase in southerly low-level flow will support 50s to low 60s F dewpoints. Thunderstorms will likely develop near the TX/NM border southward into southwest TX along a weak surface trough. This activity will likely remain isolated and only marginally severe on the back side of the MCV. Vertical shear will remain weak, but a deeply mixed boundary-layer will support strong outflow winds. Additional thunderstorms are likely to initiate on the eastern side of the MCV and within low-level convergence across the TX Panhandle/South Plains vicinity. Enhanced shear courtesy of the MCV will allow for some higher-based supercell structures. Midlevel lapse rates will remain on the weaker side, around 6.5-7 C/km, but MLCAPE around 1000-1500 J/kg in conjunction with effective shear magnitudes around 30-35 kt will support some stronger, organized updrafts capable of severe hail. Strong heating will foster steep low-level lapse rates and severe gusts also will be possible, with some potential for upscale growth during the evening near the TX/OK border into western OK. Tornado potential will likely be limited by modest boundary-layer moisture and generally weak low-level shear, but a tornado cannot be entirely ruled out given some enlargement of low-level hodographs toward 00z as a modest low level jet increases. ...Montana... An approaching midlevel trough and increasing midlevel moisture on southwesterly flow aloft will support thunderstorm development over the higher terrain of west-central MT during the afternoon. This initial activity may pose a risk for hail given modestly steep midlevel lapse rates and favorable vertical shear profiles resulting in elongated hodographs. As this activity continues northeast into the adjacent high Plains over central MT, a deeply mixed boundary-layer and light low-level winds will foster potential for strong outflow winds in addition to hail. ...Southern AL/GA into FL... A seasonally moist airmass will support widespread thunderstorm development as a weak midlevel shortwave trough migrates across the region. A weak cold front and sea breeze boundaries will focus stronger development amid modest vertical shear. Multicell clusters may produce sporadic strong/locally damaging gusts. ..Leitman.. 05/21/2023 Read more

000
ABPZ20 KNHC 211711
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sun May 21 2023

For the eastern North Pacific...east of 140 degrees west longitude:

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Kelly/Bucci

No watches are valid as of Sat May 20 21:41:02 UTC 2023.

No Mesoscale Discussions are in effect as of Sat May 20 21:41:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0248 PM CDT Sat May 20 2023 Valid 202000Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHWEST...THE RIO GRANDE VALLEY AND THE DEEP SOUTH... ...SUMMARY... Isolated and marginally severe thunderstorms are possible through this evening across parts of the Deep South, the Northwest, and the Rio Grande Valley. ...20z Update... Only minor adjustments have been made to the Marginal risk (level 1 of 5) across Deep South Texas and MS/AL. These changes are based on currently location of ongoing convection and the position of the surface cold front. Otherwise, the previous forecast is on track. For more details, see the 1630z Day 1 discussion below. ..Leitman.. 05/20/2023 .PREV DISCUSSION... /ISSUED 1126 AM CDT Sat May 20 2023/ ...Deep South... A low-amplitude shortwave trough over the Mid-MS Valley will move southeast towards the southern Appalachians, and will be preceded by an MCV currently centered on middle TN. Abundant cloud coverage across northern portions of AL/GA will limit boundary-layer destabilization to the immediate southeast of lingering stratiform rain attendant to the MCV. Amid poor mid-level lapse rates (5-5.5 C/km between 700-500 mb) sampled by the 12Z BMX/BNA soundings, the lack of more robust boundary-layer heating will likely mitigate appreciable severe potential with north/east extent. With more robust insolation underway farther south-southwest and richer boundary-layer moisture, a plume of moderate MLCAPE from 1500-2000 J/kg is anticipated across southern MS to central AL. This should support convective development trailing southwestward along/ahead of a southeast-moving cold front in the next few hours. With a predominant westerly deep-layer wind profile, effective bulk shear should be limited to around 20-25 kts where buoyancy is greater. Given the poor mid-level lapse rates upstream, hail sizes will probably remain small to marginally severe. A threat for isolated damaging winds should be the main hazard with multicell clusters that spread east-southeast and largely weaken after sunset. ...OR/WA... Somewhat greater convective coverage is anticipated relative to yesterday during the late afternoon and evening within a modest south-southwesterly deep-layer flow regime. The most likely corridor for scattered storm development is off the higher terrain in southern OR east of the Cascades, with more isolated activity possible across central WA. Where adequate effective bulk shear is present, largely close to the Cascades, marginally severe hail will be possible. Otherwise, isolated strong gusts will be possible in eastern OR given deeper mixed thermodynamic profiles with eastern extent. ...Southwest NM vicinity... A minor upper low persists near the northwest Sonora/southeast AZ border area and will drift north-northeast today. With low 50s surface dew points having spread west of the Rio Grande following a recent cold front intrusion, a pocket of weak buoyancy should develop with MLCAPE of 500-1000 J/kg. Effective bulk shear will likely remain weak, from only 20-25 kts as stronger speed shear is confined to the very upper portion of the buoyancy profile. Small to marginally severe hail and a few locally strong gusts cannot be ruled out. ...Deep South TX... A few strong storms remain possible later this afternoon as a cold front continues to move slowly southward. Buoyancy should remain moderate owing to broken cloud coverage ahead of the front. 0-6 km winds will remain unremarkable with moderate southwesterlies above that. In addition, mid-level lapse rates peaked this morning and are consistently progged to weaken through the day. Small to marginally severe hail and a few locally strong gusts cannot be ruled out. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0215 PM CDT Sat May 20 2023 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... No changes. See previous discussion below. ..Bentley.. 05/20/2023 .PREV DISCUSSION... /ISSUED 0109 AM CDT Sat May 20 2023/ ...Synopsis... On Sunday, a weak shortwave will rotate across the Central Plains as southerly flow returns moisture northward. Winds will increase but moisture return will keep relative humidity above critical thresholds. Drying conditions will be possible across the Southwest. However, winds will remain light with recent above normal rainfall leading to largely wet fuels. As such, fire weather concerns remain low with no areas included. ...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 1235 PM CDT Sat May 20 2023 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN OREGON AND WASHINGTON INTO NORTHERN IDAHO AND FAR NORTHWEST MONTANA... CORRECTED FOR SUMMARY TEXT ...SUMMARY... Severe thunderstorms are possible from eastern Oregon into far eastern Washington, northern Idaho, and far western Montana Sunday afternoon and evening. Large hail and isolated damaging gusts will be possible with these storms. ...Northern Rockies... An upper ridge will be oriented over the Great Basin and northern Rockies vicinity Sunday morning. However, a shortwave trough off the Pacific Northwest/British Columbia coast will dig southeast into the northern Rockies vicinity by the end of the period. Increasing southwesterly mid/upper-level flow will overspread eastern WA/OR into ID and western MT by afternoon. Cold temperatures aloft will support steep lapse rates over the region, with southwesterly flow increasing midlevel moisture. This will support destabilization, with MLCAPE values around 1000-2000 J/kg forecast. Low-level winds will remain somewhat light, but speed shear will create elongated hodographs and effective shear favorable for marginal supercells (around 30 kt). Large hail (to around 1.75 inch diameter) will be the main hazard, with environmental parameters supporting an upgrade to Slight risk (level 2 of 5). Some risk for strong outflow winds also will exist, especially over parts of eastern Oregon into adjacent portions of Idaho where stronger heating will support steeper low-level lapse rates. ...Southern High Plains... Thunderstorms are expected to develop over the higher terrain of central NM during the afternoon. As these storms shift east into the high Plains and interact with a weak surface trough, some strengthening of updrafts may occur. However, instability is expected to remain modest and vertical shear weak. This should limit storm organization and longevity of any stronger updrafts, and severe potential appears too limited for probabilities. ...Southeast... A weakening cold front will shift east/southeast across the region in a generally weak flow regime. Seasonal moisture ahead of the front and pockets of heating will allow for weak destabilization. A few storms could be strong enough to produce gusty winds. However, limited forcing, poor lapse rates and weak shear should limit severe potential. ..Leitman.. 05/20/2023 Read more

000
ABPZ20 KNHC 201717
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sat May 20 2023

For the eastern North Pacific...east of 140 degrees west longitude:

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Brown

MD 0824 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL OREGON
Mesoscale Discussion 0824 NWS Storm Prediction Center Norman OK 0457 PM CDT Fri May 19 2023 Areas affected...central Oregon Concerning...Severe potential...Watch unlikely Valid 192157Z - 200000Z Probability of Watch Issuance...5 percent SUMMARY...Marginally severe gusts and hail possible as thunderstorm coverage increases through the afternoon. A watch is unlikely. DISCUSSION...Visible satellite shows maturing cumulus and developing thunderstorms activity across the Fremont Mountains and Oregon High Desert. Daytime heating has allowed MLCAPE around 500-1000 J/kg across the region. RAP soundings indicate profiles are fairly dry below 500 mb with large surface dew point depressions in current surface observations, especially within the High Desert east of the Cascades (around 40-45 F in some locations). Given fairly weak deep layer shear around 15 kts, storm mode will be largely multi-cell and clustered capable of marginally severe hail and downbursts. ..Thornton/Guyer.. 05/19/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PDT...MFR...PQR... LAT...LON 44232182 45242170 45762125 46002035 45821977 45121959 43402038 43262100 43262130 43292154 43292166 43692183 44232182 Read more

WW 0227 Status Updates
STATUS REPORT ON WW 227 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0823 ..LYONS..05/19/23 ATTN...WFO...LZK...SHV...TSA...OUN...FWD... STATUS REPORT FOR WS 227 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC019-051-057-059-061-073-081-091-097-099-109-113-127-131-133- 192140- AR . ARKANSAS COUNTIES INCLUDED ARE CLARK GARLAND HEMPSTEAD HOT SPRING HOWARD LAFAYETTE LITTLE RIVER MILLER MONTGOMERY NEVADA PIKE POLK SCOTT SEBASTIAN SEVIER OKC005-013-023-029-061-063-069-077-079-089-095-121-123-125-127- 133-192140- OK . OKLAHOMA COUNTIES INCLUDED ARE ATOKA BRYAN CHOCTAW COAL HASKELL HUGHES JOHNSTON LATIMER LE FLORE MCCURTAIN MARSHALL PITTSBURG PONTOTOC POTTAWATOMIE PUSHMATAHA Read more

WW 227 SEVERE TSTM AR OK TX 191810Z - 200100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 227 NWS Storm Prediction Center Norman OK 110 PM CDT Fri May 19 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southwest Arkansas Southeast Oklahoma Northeast Texas * Effective this Friday afternoon and evening from 110 PM until 800 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2 inches in diameter possible Isolated damaging wind gusts to 70 mph possible A tornado or two possible SUMMARY...Initial thunderstorm development is underway along a west/east-oriented outflow boundary along the Red River. Additional storms will probably form to the northwest from central Oklahoma and intensify into southeast Oklahoma later this afternoon. The severe thunderstorm watch area is approximately along and 90 statute miles east and west of a line from 20 miles northeast of Poteau OK to 45 miles south southeast of Paris TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). 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 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27030. ...Grams Read more

WW 0229 Status Updates
STATUS FOR WATCH 0229 HAS NOT BEEN ISSUED YET Read more

WW 229 SEVERE TSTM TX 192020Z - 200300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 229 NWS Storm Prediction Center Norman OK 320 PM CDT Fri May 19 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of West to central Texas * Effective this Friday afternoon and evening from 320 PM until 1000 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2.5 inches in diameter possible Isolated significant damaging wind gusts to 75 mph possible SUMMARY...Initial supercell development is expected over the eastern Edwards Plateau and parts of the Permian Basin with large hail from golf ball to baseball size possible. Storms may consolidate in the Hill Country vicinity this evening with a threat for isolated severe wind gusts as well. The severe thunderstorm watch area is approximately along and 80 statute miles north and south of a line from 75 miles east of Junction TX to 35 miles north northwest of Fort Stockton 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. && OTHER WATCH INFORMATION...CONTINUE...WW 227...WW 228... AVIATION...A few severe thunderstorms with hail surface and aloft to 2.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 30020. ...Grams Read more

WW 0228 Status Updates
STATUS REPORT ON WW 228 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LEITMAN..05/19/23 ATTN...WFO...FWD... STATUS REPORT FOR WS 228 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC027-035-085-093-099-113-121-133-139-143-193-213-217-221-251- 257-281-309-333-349-367-379-397-425-439-467-192140- TX . TEXAS COUNTIES INCLUDED ARE BELL BOSQUE COLLIN COMANCHE CORYELL DALLAS DENTON EASTLAND ELLIS ERATH HAMILTON HENDERSON HILL HOOD JOHNSON KAUFMAN LAMPASAS MCLENNAN MILLS NAVARRO PARKER RAINS ROCKWALL SOMERVELL TARRANT VAN ZANDT THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more